48 resultados para ovulation synchronization


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L’envelliment de la població demana cada cop més centres especialitzats en geriatria en els països desenvolupats. Aquests mateixos països pateixen recentment una falta de personal qualificat en infermeria. Aquests dos factors es combinen i posen en evidència la necessitat de desenvolupar eines informàtiques que modernitzin les residències geriàtriques. El projecte que s’ha desenvolupat consisteix en una aplicació de gestió d’una residència geriàtrica amb una base de dades centralitzada en un PC des de la qual s’hi pot accedir a través d’una aplicació feta per PDA. La seva funció principal és poder agilitzar tota la repartició de medicació dins la residència geriàtrica, gestionant des de les pautes de medicació corresponents a cada resident, fins a un control d’stock. Consta, per tant, d’una aplicació per PC, programada amb Visual Basic i utilitzant com a base de dades Microsoft Access, i d’una aplicació per PDA, programada amb Embedded Visual Basic i utilitzant la mateixa base de dades creada per l’aplicació per PC. L’aplicació de PC proporcionarà als usuaris una gestió ràpida i còmode i, alhora, rapidesa i estalvi de treball si es vol fer un determinat manteniment a través de l’aplicació de PDA. En el manteniment de l’aplicació, però, no s’hi inclou el manteniment dels usuaris tot i haver un control d’aquests. En aquest projecte s’estudia com es desenvolupa una aplicació per PDA i com comparteix una base de dades amb una altra aplicació a través del sistema de sincronització PC↔PDA anomenat ActiveSync.

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This paper demonstrates the feasibility of a new circuit for the conversion of binary phase-shift keying signals into amplitude-shift keying signals. In its simplest form, the converter circuit is composed by a power divider, a couple of second harmonic injection-locked oscillators, and a power combiner. The operation of the converter circuit relies on the frequency synchronization of both oscillators and the generation of an interference pattern by combining their outputs, which reproduces the original phase modulation. Two prototypes of the converter have been implemented. The first one is a hybrid version working in the 400-530-MHz frequency range. The second one has been implemented using multichip-module technology, and is intended to work in the 1.8-2.2-GHz frequency range.

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We have performed a detailed study of the zenith angle dependence of the regeneration factor and distributions of events at SNO and SK for different solutions of the solar neutrino problem. In particular, we discuss the oscillatory behavior and the synchronization effect in the distribution for the LMA solution, the parametric peak for the LOW solution, etc. A physical interpretation of the effects is given. We suggest a new binning of events which emphasizes the distinctive features of the zenith angle distributions for the different solutions. We also find the correlations between the integrated day-night asymmetry and the rates of events in different zenith angle bins. The study of these correlations strengthens the identification power of the analysis.

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We propose a novel mechanism leading to spatiotemporal oscillations in extended systems that does not rely on local bulk instabilities. Instead, oscillations arise from the interaction of two subsystems of different spatial dimensionality. Specifically, we show that coupling a passive diffusive bulk of dimension d with an excitable membrane of dimension d-1 produces a self-sustained oscillatory behavior. An analytical explanation of the phenomenon is provided for d=1. Moreover, in-phase and antiphase synchronization of oscillations are found numerically in one and two dimensions. This novel dynamic instability could be used by biological systems such as cells, where the dynamics on the cellular membrane is necessarily different from that of the cytoplasmic bulk.

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A new solvable model of synchronization dynamics is introduced. It consists of a system of long range interacting tops or magnetic moments with random precession frequencies. The model allows for an explicit study of orientational effects in synchronization phenomena as well as nonlinear processes in resonance phenomena in strongly coupled magnetic systems. A stability analysis of the incoherent solution is performed for different types of orientational disorder. A system with orientational disorder always synchronizes in the absence of noise.

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Populations of phase oscillators interacting globally through a general coupling function f(x) have been considered. We analyze the conditions required to ensure the existence of a Lyapunov functional giving close expressions for it in terms of a generating function. We have also proposed a family of exactly solvable models with singular couplings showing that it is possible to map the synchronization phenomenon into other physical problems. In particular, the stationary solutions of the least singular coupling considered, f(x) = sgn(x), have been found analytically in terms of elliptic functions. This last case is one of the few nontrivial models for synchronization dynamics which can be analytically solved.

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Background: The relevance of immune-endocrine interactions to the regulation of ovarian function in teleosts is virtually unexplored. As part of the innate immune response during infection, a number of cytokines such as tumor necrosis factor alpha (TNF alpha) and other immune factors, are produced and act on the reproductive system. However, TNF alpha is also an important physiological player in the ovulatory process in mammals. In the present study, we have examined for the first time the effects of TNF alpha in vitro in preovulatory ovarian follicles of a teleost fish, the brown trout (Salmo trutta). Methods: To determine the in vivo regulation of TNF alpha expression in the ovary, preovulatory brook trout (Salvelinus fontinalis) were injected intraperitoneally with either saline or bacterial lipopolysaccharide (LPS). In control and recombinant trout TNF alpha (rtTNF alpha)-treated brown trout granulosa cells, we examined the percentage of apoptosis by flow cytometry analysis and cell viability by propidium iodide (PI) staining. Furthermore, we determined the in vitro effects of rtTNF alpha on follicle contraction and testosterone production in preovulatory brown trout ovarian follicles. In addition, we analyzed the gene expression profiles of control and rtTNF alpha-treated ovarian tissue by microarray and real-time PCR (qPCR) analyses. Results: LPS administration in vivo causes a significant induction of the ovarian expression of TNF alpha. Treatment with rtTNF alpha induces granulosa cell apoptosis, decreases granulosa cell viability and stimulates the expression of genes known to be involved in the normal ovulatory process in trout. In addition, rtTNF alpha causes a significant increase in follicle contraction and testosterone production. Also, using a salmonid-specific microarray platform (SFA2.0 immunochip) we observed that rtTNF alpha induces the expression of genes known to be involved in inflammation, proteolysis and tissue remodeling. Furthermore, the expression of kallikrein, TOP-2, serine protease 23 and ADAM 22, genes that have been postulated to be involved in proteolytic and tissue remodeling processes during ovulation in trout, increases in follicles incubated in the presence of rtTNF alpha. Conclusions In view of these results, we propose that TNF alpha could have an important role in the biomechanics of follicle weakening, ovarian rupture and oocyte expulsion during ovulation in trout, primarily through its stimulation of follicular cell apoptosis and the expression of genes involved in follicle wall proteolysis and contraction.

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La Gimnàstica Estètica de Grup (GEG) és un esport emergent del qual no existeix gairebé cap treball de camp i/o publicació. En relació al codi de puntuació d’aquesta modalitat, tant les capacitats de salt com la unitat de moviment del cos i la sincronització entre els membres del conjunt, tenen un pes molt important en la puntuació del valor tècnic i de l’execució. En aquest estudi s’ha realitzat la mesura, avaluació i comparació de les manifestacions de la força explosiva, elàstica i reactiva d’un grup de gimnàstica d’estètica d’alt nivell al principi i al final del període competitiu, mitjançant la bateria de tests de salts verticals de Bosco, concretament SJ, CMJ, CMJas i RJ (15” CMJas). També s’ha analitzat la sincronització i/o coordinació temporal intergrupal d’execució de les dificultats tècniques de salt de les coreografies competitives, al llarg del període competitiu d’un conjunt de gimnàstica estètica d’alt nivell, tenint en compte la sincronització en començar la dificultat i en acabar-la. Els resultats obtinguts demostren que la manifestació de força elàsticoexplosiva en CMJ ha disminuït un 0,46 % i la força explosiva SJ (sense reutilització d'energia elàstica ni aprofitament del reflex miotàtic) ha augmentat un 4,63 %. Durant el període competitiu del conjunt sènior de gimnàstica estètica del Club Muntanyenc Sant Cugat, la influència dels braços en la capacitat de salt ha augmentat un 1,32% i la potència anaeròbica alàctica un 4,76%. Tot i que en la majoria de tests, els resultats han estat positius, no es considera que la mostra hagi assolit una millora significativa, atès que no ha superat el 10% proposat en començar l’estudi, i els valors obtinguts són totalment inestables. S’ha vist que en un mateix test el % de pèrdues i de guanys ha estat molt variat, de manera que no es pot establir una relació de millora de la capacitat de salt en funció de l’entrenament. Pel que fa a la sincronització temporal intergrupal, ha millorat entre un 37,50% (sincronització temps inicial) i un 50,00% (sincronització temps final) en relació a les dificultats tècniques. Fet que és relaciona directament amb l’automatització de mecanismes d’execució al llarg de la temporada competitiva. Tot i així no s’ha igualat o superat la millora d’un 70% proposada per les hipòtesis inicials de l’estudi.

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Using combined emotional stimuli, combining photos of faces and recording of voices, we investigated the neural dynamics of emotional judgment using scalp EEG recordings. Stimuli could be either combioned in a congruent, or a non-congruent way.. As many evidences show the major role of alpha in emotional processing, the alpha band was subjected to be analyzed. Analysis was performed by computing the synchronization of the EEGs and the conditions congruent vs. non-congruent were compared using statistical tools. The obtained results demonstrate that scalp EEG ccould be used as a tool to investigate the neural dynamics of emotional valence and discriminate various emotions (angry, happy and neutral stimuli).

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El despliegue de un esquema de confianza es fundamental para poder desarrollar servicios de seguridad que permitan administrar y operar una red. Sin embargo, las soluciones empleadas en las redes tradicionales no se adaptan a un entorno ad hoc debido a la naturaleza dinámica y sin infraestructura de estas redes. En el presente trabajo se propone un esquema de confianza práctico y eficiente basado en una infraestructura de clave pública distribuida, umbral y jerárquica, que no requiere sincronización temporal entre todos los nodos de la red. La autorización de usuarios en el sistema se hace a través de certificados de corta duración que eliminan la necesidad de mantener la publicación y diseminación de unas listas de revocación. Por otro lado, una entidad externa de confianza permite alargar la reputación de un usuario de la red más allá de la existencia de la propia red.

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The symbol transition density in a digitally modulated signal affects the performance of practical synchronization schemes designed for timing recovery. This paper focuses on the derivation of simple performance limits for the estimation of the time delay of a noisy linearly modulated signal in the presence of various degrees of symbol correlation produced by the varioustransition densities in the symbol streams. The paper develops high- and low-signal-to-noise ratio (SNR) approximations of the so-called (Gaussian) unconditional Cramér–Rao bound (UCRB),as well as general expressions that are applicable in all ranges of SNR. The derived bounds are valid only for the class of quadratic, non-data-aided (NDA) timing recovery schemes. To illustrate the validity of the derived bounds, they are compared with the actual performance achieved by some well-known quadratic NDA timing recovery schemes. The impact of the symbol transitiondensity on the classical threshold effect present in NDA timing recovery schemes is also analyzed. Previous work on performancebounds for timing recovery from various authors is generalized and unified in this contribution.

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In this paper, the problem of frame-level symboltiming acquisition for UWB signals is addressed. The main goalis the derivation of a frame-level timing estimator which does notrequire any prior knowledge of neither the transmitted symbolsnor the received template waveform. The independence withrespect to the received waveform is of special interest in UWBcommunication systems, where a fast and accurate estimation ofthe end-to-end channel response is a challenging and computationallydemanding task. The proposed estimator is derived under theunconditional maximum likelihood criterion, and because of thelow power of UWB signals, the low-SNR assumption is adopted. Asa result, an optimal frame-level timing estimator is derived whichoutperforms existing acquisition methods in low-SNR scenarios.

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In this letter, we obtain the Maximum LikelihoodEstimator of position in the framework of Global NavigationSatellite Systems. This theoretical result is the basis of a completelydifferent approach to the positioning problem, in contrastto the conventional two-steps position estimation, consistingof estimating the synchronization parameters of the in-viewsatellites and then performing a position estimation with thatinformation. To the authors’ knowledge, this is a novel approachwhich copes with signal fading and it mitigates multipath andjamming interferences. Besides, the concept of Position–basedSynchronization is introduced, which states that synchronizationparameters can be recovered from a user position estimation. Weprovide computer simulation results showing the robustness ofthe proposed approach in fading multipath channels. The RootMean Square Error performance of the proposed algorithm iscompared to those achieved with state-of-the-art synchronizationtechniques. A Sequential Monte–Carlo based method is used todeal with the multivariate optimization problem resulting fromthe ML solution in an iterative way.

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The reproductive biology of the Mediterranean Snake cel, Ophichthus Rufus (Ophichthidae), was studied on the basis of microscopic and macroscopic analysis. Results show that O.rufus is an oviparous species with a group synchronous ovary type. The maturation process of the gonads starts in December and progress until August, when ovulation and a pawing take place. It is a fractional spawned with buoyant eggs. Potential annual fecundity estimates ranged from 1426 to 23.605 oocytes. Except for small sizes, a clear predominance of females was observed

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Este trabajo final de máster se centra en describir la realidad que afecta al periodismo de filtración. Además se analiza detalladamente el caso Planning Tool for Resource Integration, Synchronization, and Management (PRISM). Se ha averiguado qué han hecho los medios con ésta información, identificado cada elemento clave de esta trama, descrito la situación mediática actual y se han expuesto las repercusiones que ha tenido esta noticia a nivel internacional y a nivel personal. Se analizan además las noticias, artículos o ensayos que se han escrito sobre el tema para averiguar qué se ha conseguido con éste filtraje y finalmente, se han observado las consecuencias de tal acto.