981 resultados para Well-behaved solutions


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Perinatal care of pregnant women at high risk for preterm delivery and of preterm infants born at the limit of viability (22-26 completed weeks of gestation) requires a multidisciplinary approach by an experienced perinatal team. Limited precision in the determination of both gestational age and foetal weight, as well as biological variability may significantly affect the course of action chosen in individual cases. The decisions that must be taken with the pregnant women and on behalf of the preterm infant in this context are complex and have far-reaching consequences. When counselling pregnant women and their partners, neonatologists and obstetricians should provide them with comprehensive information in a sensitive and supportive way to build a basis of trust. The decisions are developed in a continuing dialogue between all parties involved (physicians, midwives, nursing staff and parents) with the principal aim to find solutions that are in the infant's and pregnant woman's best interest. Knowledge of current gestational age-specific mortality and morbidity rates and how they are modified by prenatally known prognostic factors (estimated foetal weight, sex, exposure or nonexposure to antenatal corticosteroids, single or multiple births) as well as the application of accepted ethical principles form the basis for responsible decision-making. Communication between all parties involved plays a central role. The members of the interdisciplinary working group suggest that the care of preterm infants with a gestational age between 22 0/7 and 23 6/7 weeks should generally be limited to palliative care. Obstetric interventions for foetal indications such as Caesarean section delivery are usually not indicated. In selected cases, for example, after 23 weeks of pregnancy have been completed and several of the above mentioned prenatally known prognostic factors are favourable or well informed parents insist on the initiation of life-sustaining therapies, active obstetric interventions for foetal indications and provisional intensive care of the neonate may be reasonable. In preterm infants with a gestational age between 24 0/7 and 24 6/7 weeks, it can be difficult to determine whether the burden of obstetric interventions and neonatal intensive care is justified given the limited chances of success of such a therapy. In such cases, the individual constellation of prenatally known factors which impact on prognosis can be helpful in the decision making process with the parents. In preterm infants with a gestational age between 25 0/7 and 25 6/7 weeks, foetal surveillance, obstetric interventions for foetal indications and neonatal intensive care measures are generally indicated. However, if several prenatally known prognostic factors are unfavourable and the parents agree, primary non-intervention and neonatal palliative care can be considered. All pregnant women with threatening preterm delivery or premature rupture of membranes at the limit of viability must be transferred to a perinatal centre with a level III neonatal intensive care unit no later than 23 0/7 weeks of gestation, unless emergency delivery is indicated. An experienced neonatology team should be involved in all deliveries that take place after 23 0/7 weeks of gestation to help to decide together with the parents if the initiation of intensive care measures appears to be appropriate or if preference should be given to palliative care (i.e., primary non-intervention). In doubtful situations, it can be reasonable to initiate intensive care and to admit the preterm infant to a neonatal intensive care unit (i.e., provisional intensive care). The infant's clinical evolution and additional discussions with the parents will help to clarify whether the life-sustaining therapies should be continued or withdrawn. Life support is continued as long as there is reasonable hope for survival and the infant's burden of intensive care is acceptable. If, on the other hand, the health care team and the parents have to recognise that in the light of a very poor prognosis the burden of the currently used therapies has become disproportionate, intensive care measures are no longer justified and other aspects of care (e.g., relief of pain and suffering) are the new priorities (i.e., redirection of care). If a decision is made to withhold or withdraw life-sustaining therapies, the health care team should focus on comfort care for the dying infant and support for the parents.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This Working Paper was presented at the international workshop "Game Theory in International Relations at 50", organized and coordinated by Professor Jacint Jordana and Dr. Yannis Karagiannis at the Institut Barcelona d'Estudis Internacionals on May 22, 2009. The day-long Workshop was inspired by the desire to honour the ground-breaking work of Professor Thomas Schelling in 1959-1960, and to understand where the discipline International Relations lies today vis-à-vis game theory.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present existence, uniqueness and continuous dependence results for some kinetic equations motivated by models for the collective behavior of large groups of individuals. Models of this kind have been recently proposed to study the behavior of large groups of animals, such as flocks of birds, swarms, or schools of fish. Our aim is to give a well-posedness theory for general models which possibly include a variety of effects: an interaction through a potential, such as a short-range repulsion and long-range attraction; a velocity-averaging effect where individuals try to adapt their own velocity to that of other individuals in their surroundings; and self-propulsion effects, which take into account effects on one individual that are independent of the others. We develop our theory in a space of measures, using mass transportation distances. As consequences of our theory we show also the convergence of particle systems to their corresponding kinetic equations, and the local-in-time convergence to the hydrodynamic limit for one of the models.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We propose a mixed finite element method for a class of nonlinear diffusion equations, which is based on their interpretation as gradient flows in optimal transportation metrics. We introduce an appropriate linearization of the optimal transport problem, which leads to a mixed symmetric formulation. This formulation preserves the maximum principle in case of the semi-discrete scheme as well as the fully discrete scheme for a certain class of problems. In addition solutions of the mixed formulation maintain exponential convergence in the relative entropy towards the steady state in case of a nonlinear Fokker-Planck equation with uniformly convex potential. We demonstrate the behavior of the proposed scheme with 2D simulations of the porous medium equations and blow-up questions in the Patlak-Keller-Segel model.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

PURPOSE: The purpose of this study was to characterize local distribution and systemic absorption of the tumor necrosis factor (TNF)-alpha inhibitory single-chain antibody fragment (scFv) ESBA105 following topical administration to the eye in vivo. METHODS: Rabbits received ESBA105 as topical eye drops in two dosing regimens. First, pharmacokinetics after the topical route of administration was compared to the intravenous (i.v.) route by means of applying the identical cumulative daily dose of ESBA105. In a second study rabbits received five eye drops daily for six consecutive days in a lower frequency topical dosing regimen. Kinetics and biodistribution of ESBA105 in ocular tissues and fluids as well as in sera were determined in all animals. RESULTS: After topical administration to the eye, ESBA105 quickly reaches therapeutic concentrations in all ocular compartments. Systemic exposure after topical administration is 25,000-fold lower than exposure after i.v. injection of the identical cumulative daily dose. ESBA105 levels in vitreous humor and neuroretina are significantly higher on topical administration than after i.v. injection. Absolute and relative intraocular biodistribution of ESBA105 is different with topical and systemic delivery routes. Compared to its terminal half-life in circulation (7 hours), the vitreal half-life of ESBA105 is significantly enhanced (16-24 hours). CONCLUSIONS: On topical administration, ESBA105 is efficiently absorbed and distributed to all compartments of the eye, whereby systemic drug exposure is very low. Based on its unique intraocular biodistribution and pharmacokinetics and the absolute intraocular levels reached, topical ESBA105 appears highly attractive for treatment of various ophthalmological disorders.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A family of nonempty closed convex sets is built by using the data of the Generalized Nash equilibrium problem (GNEP). The sets are selected iteratively such that the intersection of the selected sets contains solutions of the GNEP. The algorithm introduced by Iusem-Sosa (2003) is adapted to obtain solutions of the GNEP. Finally some numerical experiments are given to illustrate the numerical behavior of the algorithm.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A sequence of “inner equations” attached to certain perturbations of the McMillan map was considered in [MSS09], their solutions were used in that article to measure an exponentially small separatrix splitting. We prove here all the results relative to these equations which are necessary to complete the proof of the main result of [MSS09]. The present work relies on ideas from resurgence theory: we describe the formal solutions, study the analyticity of their Borel transforms and use ´Ecalle’s alien derivations to measure the discrepancy between different Borel-Laplace sums.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We study two cooperative solutions of a market with indivisible goods modeled as a generalized assignment game: Set-wise stability and Core. We first establish that the Set-wise stable set is contained in the Core and it contains the non-empty set of competitive equilibrium payoffs. We then state and prove three limit results for replicated markets. First, the sequence of Cores of replicated markets converges to the set of competitive equilibrium payoffs when the number of replicas tends to infinity. Second, the Set-wise stable set of a two-fold replicated market already coincides with the set of competitive equilibrium payoffs. Third, for any number of replicas there is a market with a Core payoff that is not a competitive equilibrium payoff.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

AIMS: Patients with well-tolerated sustained monomorphic ventricular tachycardia (SMVT) and left ventricular ejection fraction (LVEF) over 30% may benefit from a primary strategy of VT ablation without immediate need for a 'back-up' implantable cardioverter-defibrillator (ICD). METHODS AND RESULTS: One hundred and sixty-six patients with structural heart disease (SHD), LVEF over 30%, and well-tolerated SMVT (no syncope) underwent primary radiofrequency ablation without ICD implantation at eight European centres. There were 139 men (84%) with mean age 62 ± 15 years and mean LVEF of 50 ± 10%. Fifty-five percent had ischaemic heart disease, 19% non-ischaemic cardiomyopathy, and 12% arrhythmogenic right ventricular cardiomyopathy. Three hundred seventy-eight similar patients were implanted with an ICD during the same period and serve as a control group. All-cause mortality was 12% (20 patients) over a mean follow-up of 32 ± 27 months. Eight patients (40%) died from non-cardiovascular causes, 8 (40%) died from non-arrhythmic cardiovascular causes, and 4 (20%) died suddenly (SD) (2.4% of the population). All-cause mortality in the control group was 12%. Twenty-seven patients (16%) had a non-fatal recurrence at a median time of 5 months, while 20 patients (12%) required an ICD, of whom 4 died (20%). CONCLUSION: Patients with well-tolerated SMVT, SHD, and LVEF > 30% undergoing primary VT ablation without a back-up ICD had a very low rate of arrhythmic death and recurrences were generally non-fatal. These data would support a randomized clinical trial comparing this approach with others incorporating implantation of an ICD as a primary strategy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Static incubation tests, where microcapsules and beads are contacted with polymer and protein solutions, have been developed for the characterization of permselective materials applied for bioartificial organs and drug delivery. A combination of polymer ingress, detected by size-exclusion chromatography, and protein ingress/ egress, assessed by gel electrophoresis, provides information regarding the diffusion kinetics, molar mass cutoff(MMCO) and permeability. This represents an improvement over existing permeability measurements that are based on the diffusion of a single type of solute. Specifically, the permeability of capsules based on alginate, cellulose sulfate, polymethylene-co-guanidine were characterized as a function of membrane thickness. Solid alginate beads were also evaluated. The MMCO of these capsules was estimated to be between 80 and 90 kDa using polymers, and between 116-150 kDa with proteins. Apparently, the globular shape of the proteins (radius of gyration (Rg) of 4.2-4.6 nm) facilitates their passage through the membrane, comparatively to the polysaccharide coil conformation (Rg of 6.5-8.3 nm). An increase of the capsule membrane thickness reduced these values. The MMCO of the beads, which do not have a membrane limiting their permselective properties, was higher, between 110 and 200 kDa with dextrans, and between 150 and 220 kDa with proteins. Therefore, although the permeability estimated with biologically relevant molecules is generally higher due to their lower radius of gyration, both the MMCO of synthetic and natural watersoluble polymers correlate well, and can be used as in vitro metrics for the immune protection ability of microcapsules and microbeads. This article shows, to the authors' knowledge, the first reported concordance between permeability measures based on model natural and biological macromolecules.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Zebrafish is a good model for studying regeneration because of the rapidity with which it occurs. Better understanding of this process may lead in the future to improvement of the regenerating capacity of humans. Signaling factors are the second largest category of genes, regulated during regeneration after the regulators of wound healing. Major developmental signaling pathways play a role in this multistep process, such as Bmp, Fgf, Notch, retinoic acid, Shh, and Wnt. In the present study, we focus on TGF-β-induced genes, bigh3 and bambia. Bigh3 encodes keratoepithelin, a protein first identified as an extracellular matrix protein reported to play a role in cell adhesion, as well as in cornea formation and osteogenesis. The expression of bigh3 in zebrafish fins has previously been reported. Here we demonstrate that tgf-b1 and tgf-b3 mRNA reacted with delay, first showing no regulation at 3âeuro0/00dpa, followed by upregulation at 4 and 5âeuro0/00dpa. Tgf-b1, tgf-2, and tgf-brII mRNA were back to normal levels at 10âeuro0/00dpa. Only tgf-b3 mRNA was still upregulated at that time. Bigh3 mRNA followed the upregulation of tgf-b1, while bambia mRNA behaved similarly to tgf-b2 mRNA. We show that upregulation of bigh3 and bambia mRNA correlated with the process of fin regeneration and regulation of TGF-b signaling, suggesting a new role for these proteins.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Els canvi recents en els plans d’estudis de la UPC i la UOC tenen en compte el nou espai europeu d’educació superior (EEES). Una de les conseqüències directes a aquests canvis es la necessitat d'aprofitar i optimitzar el temps dedicat a les activitats d'aprenentatge que requereixen la participació activa de l’estudiant i que es realitzen de manera continuada durant el semestre. A més, I'EEES destaca la importància de les pràctiques, les relacions interpersonals i la capacitat per treballar en equip, suggerint la reducció de classes magistrals i l’augment d’activitats que fomentin tant el treball personal de l’estudiant com el cooperatiu. En l’àmbit de la docència informàtica d’assignatures de bases de dades el problema és especialment complex degut a que els enunciats de les proves no acostumen a tenir una solució única. Nosaltres hem desenvolupat una eina anomenada LEARN-SQL, l’objectiu de la qual és corregir automàticament qualsevol tipus de sentència SQL (consultes, actualitzacions, procediments emmagatzemats, disparadors, etc.) i discernir si la resposta aportada per l’estudiant és o no és correcta amb independència de la solució concreta que aquest proposi. D’aquesta manera potenciem l’autoaprenentatge i l’autoavaluació, fent possible la semi-presencialitat supervisada i facilitant l’aprenentatge individualitzat segons les necessitats de cada estudiant. Addicionalment, aquesta eina ajuda als professors a dissenyar les proves d’avaluació, permetent també la opció de revisar qualitativament les solucions aportades pels estudiants. Per últim, el sistema proporciona ajuda als estudiants per a que aprenguin dels seus propis errors, proporcionant retroalimentació de qualitat.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

El present Projecte de millora de la qualitat docent subvencionat pel Departament d’Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya dins del programa d’ajuts MQD-2006 convocades per l’AGAUR, s’ha desenvolupat amb els alumnes de primer de la Diplomatura de Turisme de l’Escola de Turisme i Direcció Hotelera (EUTDH) de la UAB durant el curs acadèmic 2006-2007, comptant amb la participació de l’equip docent així com amb la col·laboració i implicació directa de la direcció de l’escola. Aquest projecte parteix de la base que el desenvolupament de l’esperit emprenedor entre els estudiants és un pilar fonamental en la seva educació i preparació tant personal com professional per l’entrada amb èxit al mercat laboral. Així doncs, el fet que els estudiants mostrin més iniciativa individual així com més capacitat per buscar solucions als problemes d’una manera creativa i diferent, són aspectes bàsics d’aquest Projecte que preten, a llarg termini, repercutir en la societat, tot formant persones més emprenedores que aportin valor econòmic i social al sector turístic. Amb la finalitat d’assolir els objectius esmentats anteriorment es van realitzar una sèrie d’accions adreçades tant al professorat com a l’alumnat que portessin a canviar les actituds, comportaments i maneres de fer de la “metodologia docent tradicional”. En aquest sentit, s’han revisat les fitxes de les assignatures, tot adaptant les activitats existents o creant-ne de noves per tal de treballar les competències transversals relacionades amb el foment de l’esperit emprenedor. Tot i que aquests canvis són lents i difícils de mesurar, en general, s’ha pogut constatar com l’alumnat, en finalitzar el curs, mostra una major iniciativa, autonomía i independència i més capacitat per buscar solucions alternatives als problemes d’una manera creativa així com una actitud més favorable cap a la creació d’empreses que la que tenia al començament.