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The objective of this study was to determine the influence of hemodynamic force on the development of type III endoleak and branch thrombosis after complex endovascular thoracoabdominal aortic aneurysm repair.Patients with thoracoabdominal aortic aneurysm, within surgical range, treated with a fenestrated or branched endovascular aneurysm repair from 2014 to 2018 and with 3-month control computed tomography angiography were selected. Demographic variables, aneurysm anatomy, and endograft conformation were analyzed retrospectively from a prospective registry. The hemodynamic force was calculated using the mass and momentum conservation equations.Twenty-eight patients were included; the mean follow-up period was 24.7 ± 19.3 months. There were 102 abdominal vessels successfully catheterized (19 celiac arteries, 29 superior mesenteric arteries, 27 right renal arteries, 26 left renal arteries, and 1 polar renal artery). The rate of type III endoleak was 11.5% (n = 12); six cases were associated with branches that received two stents (P .001). A higher rate of endoleak was observed with wider stents (8.50 ± 1.0 mm vs 7.17 ± 1.3 mm; P = .001) but not with longer stents (P = .530). All cases of type III endoleak affected visceral arteries (eight celiac arteries and four superior mesenteric arteries). The freedom from type III endoleak at 24 months was 86%. The rate of thrombosis was 5.9% (n = 6). A higher rate of thrombosis was observed in smaller vessels (5.00 ± 1.3 mm vs 7.16 ± 1.8 mm; P = .001), with higher stent oversizing (36.87% ± 23.6% vs 5.52% ± 15.0%; P .001), and with a higher angle of curvature (124.33 ± 86.1 degrees vs 57.71 ± 27.9 degrees; P .001). All cases of thrombosis were related to renal arteries (two left renal arteries, two right renal arteries, and two polar renal arteries). The freedom from thrombosis at 24 months was 92%. The area under the curve for the angle of curvature was 0.802 (95% confidence interval, 0.661-0.943; P = .013), and the cutoff point was established at 59.5 degrees (sensitivity, 100%; specificity, 60.4%). The receiver operating characteristic curve for the stent oversize showed an area under the curve of 0.903 (95% confidence interval, 0.821-0.984; P = .001), and the cutoff point was 14.5% (sensitivity, 100%; specificity, 77.1%). A higher hemodynamic force was associated with thrombosis (23.35 × 10Longer stents should be preferred to avoid type III endoleak. A higher angle of curvature leads to a higher hemodynamic force that results in a higher rate of thrombosis. Accordingly, we recommend maintaining the angle of curvature under 59.9 degrees. Small vessels and excessive stent oversizing entail a higher risk of thrombosis; as such, we advise a maximum stent oversize of 14.5%. Renal arteries are more susceptible to thrombosis, whereas visceral arteries are more prone to endoleak.

espanolAntecedentes y objetivo La informacion que se proporciona a los pacientes se realiza de manera escrita en forma de consentimiento informado (CI), y la legibilidad de los textos es clave en la actividad asistencial. Se evaluo la legibilidad de los documentos de CI publicados por el Capitulo de Cirugia Endovascular (CCEV) de la Sociedad Espanola de Angiologia y Cirugia Vascular (SEACV) en 2019, y su evolucion con respecto a los publicados en 2007. Materiales y metodos Se agruparon los CI por sectores, obteniendose los parametros: silabas, palabras, frases, promedio palabras/frases y silabas/palabras, indices de Flesch, de Flesch-Szigriszt, de Fernandez-Huerta y de Gunning-Fog, y el grado en la escala Inflesz. Resultados El indice de Flesch les otorgo una clasificacion muy dificil a los CI del CCEV, y el indice de Gunning-Fog reflejo una legibilidad equivalente a textos universitarios. Los indices de Flesch-Szigriszt, Fernandez-Huerta y la escala Inflesz los calificaron como normales. Los CI con menor legibilidad fueron los de troncos supraaorticos (TSA) y miscelanea en los indices de Fernandez-Huerta (p Conclusiones Aunque los CI del CCEV presentan una legibilidad normal, se ha observado una disminucion en los indices de legibilidad respecto a los publicados en 2007. Ademas, deberian revisarse la extension y el contenido de los CI, especialmente los referentes a TSA y miscelanea. EnglishBackground and objective Doctors provide patients the information in written form by informed consents (IC), being the readability essential in the quality of care. The primary endpoint was to analyze the readability of IC published by the Chapter of Endovascular Surgery (CCEV) of the Spanish Society of Angiology and Vascular Surgery (SEACV) in 2019, and its evolution to those published by the SEACV in 2007. Materials and methods The ICs were organized by sectors and we obtained the following parameters: syllables, words, phrases, average words/phrases and syllables/words, Flesch, Flesch-Szigriszt, Fernandez-Huerta and Gunning-Fog indexes, as well as the grade on the Inflesz scale. Results The Flesch index classified the CCEV consents as very difficult, and the Gunning-Fog index reflected a readability equivalent to university texts. The Flesch-Szigriszt, Fernandez-Huerta indexes and Inflesz scale classified them as normal. The ICs with less readability were those referring to supra-aortic trunks (SAT) and miscellaneous in the Fernandez-Huerta (P Conclusions Although CCEV consents had a normal readability, it has been observed a decrease in the readability indexes compared to those published in 2007 by the SEACV. In addition the length and content of the ICs should be reviewed, especially those relating to SAT and miscellaneous.

This paper describes a localization module for an autonomous wheelchair. This module includes a combination of various sensors such as odometers, laser scanners, IMU and Doppler speed sensors. Every sensor used in the module features variable covariance estimation in order to yield a final accurate localization. The main problem of a localization module composed of different sensors is the accuracy estimation of each sensor. Average static values are normally used, but these can lead to failure in some situations. In this paper, all the sensors have a variable covariance estimation that depends on the data quality. A Doppler speed sensor is used to estimate the covariance of the encoder odometric localization. Lidar is also used as a scan matching localization algorithm, comparing the difference between two consecutive scans to obtain the change in position. Matching quality gives the accuracy of the scan matcher localization. This structure yields a better position than a traditional odometric static covariance method. This is tested in a real prototype and compared to a standard fusion technique.

Doctors provide patients the information in written form by informed consents (IC), being the readability essential in the quality of care. The primary endpoint was to analyze the readability of IC published by the Chapter of Endovascular Surgery (CCEV) of the Spanish Society of Angiology and Vascular Surgery (SEACV) in 2019, and its evolution to those published by the SEACV in 2007.The ICs were organized by sectors and we obtained the following parameters: syllables, words, phrases, average words/phrases and syllables/words, Flesch, Flesch-Szigriszt, Fernández-Huerta and Gunning-Fog indexes, as well as the grade on the Inflesz scale.The Flesch index classified the CCEV consents as very difficult, and the Gunning-Fog index reflected a readability equivalent to university texts. The Flesch-Szigriszt, Fernández-Huerta indexes and Inflesz scale classified them as normal. The ICs with less readability were those referring to supra-aortic trunks (SAT) and miscellaneous in the Fernández-Huerta (P.020 and P.05, respectively) and Flesch-Szigriszt (P.05) indexes. However, ICs regarding venous pathology showed a better readability in this indexes (P.006). CCEV consents were significantly longer than SEACV consents (P=.021). In addition, there was a decrease over time in the mean value of the Fernandez-Huerta and Flesch-Szigriszt indexes (P=.002).Although CCEV consents had a normal readability, it has been observed a decrease in the readability indexes compared to those published in 2007 by the SEACV. In addition the length and content of the ICs should be reviewed, especially those relating to SAT and miscellaneous.

Treballs finals del Màster en Matemàtica Avançada, Facultat de matemàtiques, Universitat de Barcelona, Any: 2018, Director: Marta Sanz, [en] In this project we introduce stochastic partial differential equations (SPDEs), focusing on the stochastic wave equation. We start by defining the Wiener integral with respect to space-time white noise. This integral allows us to provide the notion of random field solution of an SPDE. Once we have shown the existence of random field solution of the one-dimensional stochastic linear wave equation, our main goal will be to prove results on the Hölder continuity of its sample paths when the domains are $\mathbb{R}_{+}$ and [0, $L$]. We also study the nonlinear case, which requires the use of another integral whose integrand can be random, in contrast to the Wiener integral. To define this integral, we follow Walsh’s approach [13]. We prove a theorem on existence and uniqueness of random field solution to nonlinear SPDEs and then state sufficient conditions yielding the Hölder continuity of its sample paths. Finally, we apply these results to conclude that the stochastic nonlinear wave equation has a random field solution and its sample paths are jointly Hölder continuous under some given conditions.

Treballs Finals de Grau de Matemàtiques, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2017, Director: Marta Sanz, [en] We start by defining the stochastic integral with respect continuous semimartingales. We then derive Itô’s formula and we show two important applications of this formula: Lévy’s characterization of Brownian motion and the Burkholder-Davis-Gundy inequalities. We extend Itô’s formula for convex functions by using local times. Finally, we apply the theory of local times to the case of Brownian motion: we proof the classical Trotter theorem and we identify the law of the Brownian local time at level 0.

Resumen Objetivo Los estrogenos han sido implicados en el desarrollo de patologia aterosclerotica a nivel de las extremidades inferiores y la aorta abdominal. El estudio de la historia reproductiva de las pacientes con estenosis carotidea puede contribuir al conocimiento de los factores de riesgo de aterosclerosis. El objetivo principal de este estudio fue investigar si existen diferencias en la historia reproductiva entre mujeres con patologia oclusiva carotidea y mujeres sanas, asi como su influencia en el grado de severidad de la misma. Material y metodos Se realizo un estudio de casos y controles incluyendo a 153 pacientes con (78) y sin (75) patologia oclusiva carotidea. Las pacientes con estenosis de carotida se subdividieron segun el estudio mediante eco-Doppler en ligera ( Resultados Ambos grupos fueron comparables en edad, peso, altura y comorbilidades. Se encontraron diferencias significativas en cuanto al numero de hijos (1,4 ± 1 vs. 3,2 ± 2, p = 0,04) y uso de estatinas (92,0 ± 28% vs. 13,3 ± 35%, p = 0,02), siendo mayor en el grupo de mujeres con patologia carotidea. La influencia de posibles factores hormonales como la edad de menarquia y menopausia, asi como la toma de anticonceptivos orales o sustitutos estrogenicos, no se demostro durante el estudio. No existieron diferencias significativas en la historia reproductiva entre los diferentes grados de estenosis carotidea. Conclusiones La multiparidad se asocia a un incremento de patologia oclusiva carotidea. Este hallazgo sugiere que la maternidad podria comportarse como un factor de riesgo aterosclerotico y deberia considerarse al establecer el riesgo cardiovascular en mujeres. El verdadero papel de los estrogenos sobre la patologia oclusiva carotidea necesita ser todavia estudiado.

Objective The main objective of this research is the design and implementation of a new fuzzy logic tool for automatic drug delivery in patients undergoing general anesthesia. The aim is to adjust the drug dose to the real patient needs using heuristic knowledge provided by clinicians. A two-level computer decision system is proposed. The idea is to release the clinician from routine tasks so that he can focus on other variables of the patient. Methods The controller uses the Bispectral Index (BIS) to assess the hypnotic state of the patient. Fuzzy controller was included in a closed-loop system to reach the BIS target and reject disturbances. BIS was measured using a BIS VISTA monitor, a device capable of calculating the hypnosis level of the patient through EEG information. An infusion pump with propofol 1% is used to supply the drug to the patient. The inputs to the fuzzy inference system are BIS error and BIS rate. The output is infusion rate increment. The mapping of the input information and the appropriate output is given by a rule-base based on knowledge of clinicians. Results To evaluate the performance of the fuzzy closed-loop system proposed, an observational study was carried out. Eighty one patients scheduled for ambulatory surgery were randomly distributed in 2 groups: one group using a fuzzy logic based closed-loop system (FCL) to automate the administration of propofol (42 cases); the second group using manual delivering of the drug (39 cases). In both groups, the BIS target was 50. Conclusions The FCL, designed with intuitive logic rules based on the clinician experience, performed satisfactorily and outperformed the manual administration in patients in terms of accuracy through the maintenance stage.

Thoracic endovascular aortic repair (TEVAR) is a minimally invasive, and generally excellent, technique to treat thoracic aortic aneurysms, dissections, or traumatic aortic transections. Aortoesophageal fistula (AEF) is a highly lethal cause of massive bleeding and a catastrophic complication after TEVAR. The incidence of AEF after TEVAR has been reported as between 5% and 10.53%. We present 3 cases of AEF after TEVAR, and our experience with management and outcome of these patients. A review of the recent literature has been included. These findings emphasize the importance of mediastinal infection, esophageal surgical management, and aorta replacement. Management should be surgical, since the outcome under conservative management seems almost invariably fatal. Future developments in endoprosthesis design and material, and avoidance of oversizing will hopefully reduce the occurrence of this disastrous complication.

Two composts produced at different times of the year from garden waste, sewage sludge and wood ash were evaluated for use as ornamental plant substrates. The maturity and lack of phytotoxicity of both composts, as well as the absence of E. coli, were first confirmed by use of laboratory procedures and rapid test kits. A greenhouse experiment was then carried out with two ornamental species, Petunia sp. and Tagetes sp., to evaluate the suitability of the composts as plant substrates. The performance of the composts as well as mixtures of each with 25, 50 and 75% acid peat moss was compared with that of a commercial universal substrate. Addition of the peat to the composts improved some of the physical and chemical properties. However, the results of the pot experiments indicated that under the experimental conditions used, the compost produced from green waste was suitable for use as a plant substrate, without the need for addition of other components; this appears to be an effective way of utilizing the t...

The spatiotemporal dissemination of Citrus tristeza virus (CTV) was evaluated by DASI-ELISA in orange and grapefruit fields of six citrus producing regions in Cuba, and aphid populations were evaluated in two selected areas. The aphid species found in these areas were Toxoptera citricida (the most efficient vector of CTV), T. aurantii and Aphis spiraecola. A logistic model was the most appropriate to explain the temporal increase in the proportion of CTV-infected plants for almost all the fields. Although nearly all areas showed an increase in this proportion, there were regions of low CTV spread, which was slower in grapefruit than in orange fields. 2DCORR analysis indicated spatial dependence among immediately adjacent trees, higher in the within-row direction than in the across-row direction. Aggregation was also detected by dispersion index and binary power law fitting within quadrats of all sizes. For most fields, autocorrelation analysis showed a significant edge effect and spatial dependence among infected plants of different sub-areas. Based on these results a new tristeza management strategy was proposed for each region of the country.

The slow growth of Mycobacterium avium subsp. paratuberculosis (Map) has hindered its investigation. No data concerning the presence of paratuberculosis in Mexico are currently available. The aim of this study was to identify M. avium subsp. paratuberculosis infection in sheep and goat flocks from several states in Mexico. Twenty-two animals, all manifesting clinical signs of paratuberculosis were obtained from six different Mexican states. Of these, 14 sheep and 8 goats were serologically diagnosed and multibacillary type lesions were identified. On the basis of mycobacteria concentration technique used for ileal mucosa, Map identification was confirmed by means of PCR and bacterial culture. In addition, samples were classified according to the abundance of acid-fast bacteria (AFB) identified in the intestinal mucosa and by the final concentrate of mycobacteria and the amount of DNA obtained. All correlations concerning the abundance of AFB in tissue, AFB recovered in the final concentrate and the amount of DNA obtained were recorded. These findings will allow to predict the amount of DNA which can be obtained by referring to the abundance of acid-fast organisms found in the tissue and, therefore, define the potential of using this method for the purpose of Map characterization. The results of this study indicate that paratuberculosis is widespread among goats and sheep in Mexico.

The aim of this paper is to provide a novel approach to the classical problem of testing the Gaussianity of a stationary process where the data can be assumed to be independent and identically distributed. Some results of Large Deviations theory are used to select a set of asymptotically optimal test statistics so that their combination results in a suitable detection procedure. The Johnson system of distributions has been used as the basis for the design of the detector. The fact that the good asymptotical properties can be extended to finite samples with small sizes provides the motivation for the rest of the work. In this respect, the performance of the proposed procedure is also compared with that of some known Gaussianity tests. The possibility to directly calculate a reliable measure of support such as the Bayesian posterior probabilities, as opposed to P-values, is an additional advantage. Furthermore, it will be shown how the proposed procedure can provide some extra information concerning the type of deviation from Gaussianity, which is present in the data.

A new approach to the classical problem of determining whether or not a set of data has been sampled from a univariate normal distribution is considered. The problem is posed in a pattern recognition framework and the concept of an asymptotically optimal expert is introduced. Some results of Large Deviation theory are used in the selection of experts so that their combined abilities lead to a suitable discrimination procedure. The fact that good asymptotical properties can be extended to finite samples with small sizes is the basis for the rest of the work. The performance of the proposed procedure is also compared to that of some known normality tests. An additional advantage of the procedure is the possibility of computing a reliable measure of support such as the Bayesian posterior probabilities as opposed to the P-values. Furthermore, some extra information can be obtained concerning the type of deviation from normality which is present in the data.

In this study, a procedure planning for a Computer Architecture Course that tries to create a balance between simulation and laboratory procedures is presented. For this planning, we use hardware implementation for parts of this subject that require careful dedication because of its complexity: interconnection networks and parallel processing. On the other hand, we use simulation packages for the teaching of pipelined and vectorial processors. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 11–17, 2002; Published online in Wiley InterScience (www.interscience.wiley.com.); DOI 10.1002/cae.10012

A Fuzzy Finite State Machine (FFSM) is an extension of the classical Finite Deterministic Automaton (FDA). This algorithm finds many applications in several fields as pattern recognition, intelligent agent modeling, human - machine interfaces, and finally but not less important control engineering. This paper proposes novel strategies to approach two of the main problems in designing FFSMs: structure definition from a “seed” FDA (basic prototype), and simplification of the resulting model according to the statistical features of both external and feedback inputs.

This paper presents a knowledge-based system for aiding in the decision-making process that is carried out in hospital management. There are a number of reasons that have led us to choose a tool such as this one: the amount of information generated in a hospital, its great interrelation and the need of heuristic knowledge for its processing. The KBS has been designed following the KADS methodology. KADS has allowed us to obtain a structured representation of the knowledge, which makes easier both the construction and the debugging of the knowledge base. As a starting point, the decision-making task has been decomposed in four subtasks: monitoring; diagnosis; prediction of the possible solutions for the stated problem; and design of the solution. The prediction task can only be performed through a simulation program where the dynamics of the hospital is modeled. This allows the system to detect the consequences of the application of different possible solutions. The co-operation between simulation and artificial intelligence has proven to be an adequate technique for dealing with the decision-making tasks that are involved with the management of complex organizations.

The objective of our research is to develop computer-based tools to automate the clinical evaluation of the electroencephalogram (EEG) and visual evoked potentials (VEP). This paper describes a set of solutions to support all the aspects regarding the standard procedures of the diagnosis in neurophysiology, including: (1) acquisition and real-time processing and compression of EEG and VEP signals, (2) real-time brain mapping of spectral powers, (3) classifier design, (4) automatic detection of morphologies through supervised neural networks. (5) signal analysis through fuzzy modelling, and (6) a knowledge based approach to classifier design.

An undergraduate level laboratory course on digital signal processors and their use in real-time digital signal processing (DSP) systems is described. Special emphasis is put on some practical issues such as execution time optimization, finite wordlength effects and a pipelined strategy as a suitable way to improve the performance of a real-time DSP system. The primary purpose of the laboratory is a better understanding of the theoretical concepts and a more active participation of the students in the course. The authors think that this paper will be of interest to those teaching related courses such as Introduction to DSP, Digital Signal Processing, Real-time DSP, Microprocessors and Hardware/Softmare Interaction. The well-known Texas Instruments' TMS320C2x and TMS320C5x fixed-point processors are used as the fundamental tool in the lab experiments and the TMS320C3x is suggested as a low-cost floating-point alternative. Enough detail is provided in the paper to duplicate certain parts of the experiments.

The study of a particular complex system by means of computer simulation is described in this paper. Hospitals are chosen as target systems where the proposed methodology is applied.In order to choose the right decisions, hospital managers need all the information about the functioning of the organization. This research project presents a simulation tool that allows virtual societies such as hospitals to be implemented. In this way, the study of emergent behaviours in these systems can be carried out.Petri nets were initially tested as a methodology to model the hospital. However, the complexity of the resulting model led us to follow a process oriented approach.

This paper researches a collaborative strategy between an XCS learning classifier system (LCS) and a relational learning (RL) agent. The problem here is to learn a relational policy for a stochastic markovian decision process. In the proposed method the XCS agent is used to improve the performance of the RL agent by filtering the samples used at the induction step. This research shows that in these conditions, one of the main benefits of using the XCS algorithm comes from selecting the examples for relational learning using an estimation for the accuracy of the predicted value at each state-action pair. This kind of transfer learning is important because the characteristics of both agents are complementary: the RL agent incrementally induces a high level description of a policy, while the LCS agent offers adaptation to changes in the environment.

Transfer learning, using systems with rich and general representations, to improve adaptive rule based systems designed to efficiently react in changing environments is the idea behind the problem studied in this paper. In this framework, the aim of this research is studying the benefits of using relational learning in combination with an evolutionary propositional learning system as XCS. The proposed method starts by learning a first order relational decission tree using a set of simplified instances of a problem. The learned relational model is then used to help a learning classifier system to deal with a more complex instance of the task. The researched strategy is based on injecting rules derived from the relational model in the discovering subsystem of the XCS. Results show that this method can be used to automatically adapt the behaviour of a learning rule based system when the environment increases its complexity.

The objective of this research is to design a pattern recognition system based on a Fuzzy Finite State Machine (FFSM). We try to find an optimal FFSM with Genetic Algorithms (GA). In order to validate this system, the classifier has been applied to a real problem: distinction between normal and abnormal cells in cytological breast fine needle aspirate images and cytological peritoneal fluid images. The characteristic used in the discrimination between normal and abnormal cells is a texture measurement of the chromatin distribution in cellular nuclei. Furthermore, the effectiveness of this method as a pattern classifier is compared with other existing supervised and unsupervised methods and evaluated with Receiver Operating Curves (ROC) methodology.

SICOLE is a research effort to develop a software environment to help tutors of dyslexic children with the diagnostic and treatment tasks. This paper describes the architecture of the package already implemented where three important elements interact: a multimedia interface, an inference module and a database. This architecture provides the system with the flexibility to support a large variety of tasks, dynamic presentations, and complex teaching strategies. The application of speech recognition technology is also researched as an important part of the evaluation of the dyslexic children improvements. This package is being used at the present moment in several Spanish Schools as part of its validation process.

The objective of our research is to develop computer-based tools to automate the clinical evaluation of the electroencephalogram (EEG) and visual evoked potentials (VEP). This paper describes a set of solutions to support all the aspects regarding the standard procedures of the diagnosis in neurophysiology, including: (1) acquisition and real-time processing and compression of EEG and VEP signals, (2) real-time brain mapping of spectral powers, (3) classifier design, (4) automatic detection of morphologies through supervised neural networks. (5) signal analysis through fuzzy modelling, and (6) a knowledge based approach to classifier design.

Continuous biomedical parameters are normally hybrid signals, because they contain both sub-symbolic and symbolic information. This paper describes a methodology to design adequate processing systems for the automatic analysis of this kind of signals. The methodology is supported by the concept of fuzzy system.

This paper presents a set of methods for helping in the analysis of signals with particular features that admit a symbolic description. The methodology is based on a general discrete model for a symbolic processing subsystem, which is fuzzyfied by means of a fuzzy inference system. In this framework a number of design problems have been approached. The curse of dimensionality problem and the specification of adequate membership functions are the main ones. In addition, other strategies, which make the design process simpler and more robust, are introduced. Their goals are automating the production of the rule base of the fuzzy system and composing complex systems from simpler subsystems under symbolic constrains. These techniques are applied to the analysis of wakefulness episodes in the sleep EEG. In order to solve the practical difficulty of finding remarkable situations from the outputs of the symbolic subsystems an unsupervised adaptive learning technique (FART network) has been applied.

This paper presents an Adaptive Multimedia Interface embedded in an Intelligent Tutorial System (ITS) for intellectual and cognitive handicapped children. There are many educational programs specifically designed for helping students but in general they do not consider the adaptation of the performed tasks to the individual characteristics of each one of the children. The aim of this work is designing a computer-based environment for supporting a teaching strategy where both the pedagogic aspects and the learning goals were adapted according to the particularities of the pupil. The two fundamental problems that are approached in this paper are: designing the interface that is embedded in an Intelligent Tutorial System and implementing an efficient communication of knowledge.