953 resultados para Partial nephrectomy
Resumo:
We use many-body theory to find the asymptotic behaviour of second-order correlation corrections to the energies and positron annihilation rates in many- electron systems with respect to the angular momenta l of the single-particle orbitals included. The energy corrections decrease as 1/(l+1/2)4, in agreement with the result of Schwartz, whereas the positron annihilation rate has a slower 1/(l+1/2)2 convergence rate. We illustrate these results by numerical calculations of the energies of Ne and Kr and by examining results from extensive con?guration-interaction calculations of PsH binding and annihilation.
Resumo:
We study the solution concepts of partial cooperative Cournot-Nash equilibria and partial cooperative Stackelberg equilibria. The partial cooperative Cournot-Nash equilibrium is axiomatically characterized by using notions of rationality, consistency and converse consistency with regard to reduced games. We also establish sufficient conditions for which partial cooperative Cournot-Nash equilibria and partial cooperative Stackelberg equilibria exist in supermodular games. Finally, we provide an application to strategic network formation where such solution concepts may be useful.
Resumo:
This study investigates face recognition with partial occlusion, illumination variation and their combination, assuming no prior information about the mismatch, and limited training data for each person. The authors extend their previous posterior union model (PUM) to give a new method capable of dealing with all these problems. PUM is an approach for selecting the optimal local image features for recognition to improve robustness to partial occlusion. The extension is in two stages. First, authors extend PUM from a probability-based formulation to a similarity-based formulation, so that it operates with as little as one single training sample to offer robustness to partial occlusion. Second, they extend this new formulation to make it robust to illumination variation, and to combined illumination variation and partial occlusion, by a novel combination of multicondition relighting and optimal feature selection. To evaluate the new methods, a number of databases with various simulated and realistic occlusion/illumination mismatches have been used. The results have demonstrated the improved robustness of the new methods.
Resumo:
This paper proposes a hybrid transmission technique based on adaptive code-to-user allocation and linear precoding for the downlink of phase shift keying (PSK) based multi-carrier code division multiple access (MC-CDMA) systems. The proposed scheme is based on the separation of the instantaneous multiple access interference (MAI) into constructive and destructive components taking into account the dependency on both the channel variation and the instantaneous symbol values of the active users. The first stage of the proposed technique is to adaptively distribute the available spreading sequences to the users on a symbol-by-symbol basis in the form of codehopping with the objective to steer the users' instantaneous crosscorrelations to yield a favourable constructive to destructive MAI ratio. The second stage is to employ a partial transmitter based zero forcing (ZF) scheme specifically designed for the exploitation of constructive MAI. The partial ZF processing decorrelates destructive interferers, while users that interfere constructively remain correlated. This results in a signal to interference-plus-noise ratio (SINR) enhancement without the need for additional power-per-user investment. It will be shown in the results section that significant bit error rate (BER) performance benefits can be achieved with this technique.
Resumo:
We investigate how a group of players might cooperate with each other within the setting of a non-cooperative game. We pursue two notions of partial cooperative equilibria that follow a modification of Nash's best response rationality rather than a core-like approach. Partial cooperative Nash equilibrium treats non-cooperative players and the coalition of cooperators symmetrically, while the notion of partial cooperative leadership equilibrium assumes that the group of cooperators has a first-mover advantage. We prove existence theorems for both types of equilibria. We look at three well-known applications under partial cooperation. In a game of voluntary provision of a public good we show that our two new equilibrium notions of partial cooperation coincide. In a modified Cournot oligopoly, we identify multiple equilibria of each type and show that a non-cooperator may have a higher payoff than a cooperator. In contrast, under partial cooperation in a symmetric Salop City game, a cooperator enjoys a higher return.
Resumo:
A service is a remote computational facility which is made available for general use by means of a wide-area network. Several types of service arise in practice: stateless services, shared state services and services with states which are customised for individual users. A service-based orchestration is a multi-threaded computation which invokes remote services in order to deliver results back to a user (publication). In this paper a means of specifying services and reasoning about the correctness of orchestrations over stateless services is presented. As web services are potentially unreliable the termination of even finite orchestrations cannot be guaranteed. For this reason a partial-correctness powerdomain approach is proposed to capture the semantics of recursive orchestrations.
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AIM:
We examined the effect of partial hearing, including cochlear implantation, on the development of motor skills in children (aged 6-12y).
METHOD:
Three independent groups of children were selected: a partial hearing group (n=25 [14 males, 11 females]; mean age 8y 8mo, SD 1y 10mo), a nonverbal IQ-matched group (n=27 [15 males, 12 females]; mean age 9y, SD 1y 6mo), and an age-matched group (n=26 [8 males, 18 females]; mean age 8y 8mo, SD 1y 7mo) from three schools with special units for children with partial hearing. All children with partial hearing had a bilateral hearing loss >60 decibels. Motor and balance skills were assessed using the Movement Assessment Battery for Children (MABC) and two protocols from the NeuroCom Balance Master clinical procedures.
RESULTS:
The mean standardized total MABC score of the children with partial hearing (95% confidence interval [CI] 71.8-88.7) was significantly lower than both the age-matched (95% CI 95.8-111.4; p<0.01) and the IQ-matched (95% CI 87.6-103.0; p=0.03) comparison groups. The children with partial hearing had particular difficulties with balance, most notably during tests of intersensory demand. However, subgroup analyses revealed that the effect of cochlear implantation was clearly dependent on the nature of the task.
INTERPRETATION:
Children with partial hearing are at high risk of clinical levels of motor deficit, with balance difficulties providing support for conventional vestibular deficit theory. However, the effect of cochlear implantation suggests that other sensory systems may be involved. A broader ecological perspective, which takes into account factors external to the child, may prove a useful framework for future research.
Resumo:
Motivation: We study a stochastic method for approximating the set of local minima in partial RNA folding landscapes associated with a bounded-distance neighbourhood of folding conformations. The conformations are limited to RNA secondary structures without pseudoknots. The method aims at exploring partial energy landscapes pL induced by folding simulations and their underlying neighbourhood relations. It combines an approximation of the number of local optima devised by Garnier and Kallel (2002) with a run-time estimation for identifying sets of local optima established by Reeves and Eremeev (2004).
Results: The method is tested on nine sequences of length between 50 nt and 400 nt, which allows us to compare the results with data generated by RNAsubopt and subsequent barrier tree calculations. On the nine sequences, the method captures on average 92% of local minima with settings designed for a target of 95%. The run-time of the heuristic can be estimated by O(n2D?ln?), where n is the sequence length, ? is the number of local minima in the partial landscape pL under consideration and D is the maximum number of steepest descent steps in attraction basins associated with pL.
Resumo:
1. Extracts of the liver fluke, Fasciola hepatica from three different hosts (cow, sheep, rat) have been subjected to radioimmunoassay using antisera to 6 mammalian regulatory peptides.
Resumo:
The localisation and distribution of the cytoskeletal protein tubulin in the adult liver fluke Fasciola hepatica have been determined by an indirect immunofluorescence technique using a monoclonal antibody raised against beta-tubulin. Tubulin was demonstrated in the tegumental syncytium and in the tegumental cell bodies and their cytoplasmic connections with the surface syncytium. Immunostaining was also evident in the nerve fibres innervating sensory receptors in the tegument, in the nerve plexus innervating the sub-tegumental musculature and in the cytoplasmic extensions of the nurse cells within the vitelline follicle. Immunoblotting of whole fluke fractions produced a single band corresponding to a molecule of approximately 54 kDa in size. This figure corresponds with previous data obtained on tubulin from other helminth and eukaryotic sources.