Generic system for human-computer gesture interaction

Hand gestures are a powerful way for human communication, with lots of potential applications in the area of human computer interaction. Vision-based hand gesture recognition techniques have many proven advantages compared with traditional devices, giving users a simpler and more natural way to communicate with electronic devices. This work proposes a generic system architecture based in computer vision and machine learning, able to be used with any interface for humancomputer interaction. The proposed solution is mainly composed of three modules: a pre-processing and hand segmentation module, a static gesture interface module and a dynamic gesture interface module. The experiments showed that the core of vision-based interaction systems can be the same for all applications and thus facilitate the implementation. In order to test the proposed solutions, three prototypes were implemented. For hand posture recognition, a SVM model was trained and used, able to achieve a final accuracy of 99.4%. For dynamic gestures, an HMM model was trained for each gesture that the system could recognize with a final average accuracy of 93.7%. The proposed solution as the advantage of being generic enough with the trained models able to work in real-time, allowing its application in a wide range of human-machine applications.

Strategies to combat infections of Acinetobacter baumannii biofilms

Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Engenharia Clínica)

Search for new phenomena in events with three or more charged leptons in pp collisions at TeV with the ATLAS detector

A generic search for anomalous production of events with at least three charged leptons is presented. The data sample consists of pp collisions at s√=8 TeV collected in 2012 by the ATLAS experiment at the CERN Large Hadron Collider, and corresponds to an integrated luminosity of 20.3 fb−1. Events are required to have at least three selected lepton candidates, at least two of which must be electrons or muons, while the third may be a hadronically decaying tau. Selected events are categorized based on their lepton flavour content and signal regions are constructed using several kinematic variables of interest. No significant deviations from Standard Model predictions are observed. Model-independent upper limits on contributions from beyond the Standard Model phenomena are provided for each signal region, along with prescription to re-interpret the limits for any model. Constraints are also placed on models predicting doubly charged Higgs bosons and excited leptons. For doubly charged Higgs bosons decaying to eτ or μτ, lower limits on the mass are set at 400 GeV at 95% confidence level. For excited leptons, constraints are provided as functions of both the mass of the excited state and the compositeness scale Λ, with the strongest mass constraints arising in regions where the mass equals Λ. In such scenarios, lower mass limits are set at 3.0 TeV for excited electrons and muons, 2.5 TeV for excited taus, and 1.6 TeV for every excited-neutrino flavour.

Novel strategies to combat gram-negative bacterial pathogens using bacteriophage proteins

Dissertação de mestrado em Bioengenharia

Derechos de participación e información en programas dirigidos a adolescentes en escuelas secundarias de la Ciudad de Córdoba: cumplimiento progresivo y estrategias de promoción. Participation and information rights in programs for adolescents in secondary schools in Cordoba City: progressive implementation and promotion strategies.

Abordar la infancia desde el enfoque de derechos (ED) implica una lectura de los derechos de los cuales los niños, niñas y adolescentes (NNA) son titulares y de las acciones estatales que se implementan para viabilizar el ejercicio concreto de ellos. Esta perspectiva exige comprender los contenidos de las políticas púb,el grado de participación que se les asigna y los sentidos que ellas toman en términos de progresividad de los derechos. Los cambios de concepción de la infancia desde la Convención Internacional de los Derechos del Niño (CIDN) y los cambios legislativos interpelan al Estado y la sociedad a modificar la visión hegemónica. Nuestra hipótesis gira alrededor de las siguientes considerac.: se han producido algunas modificaciones en las políticas y acciones estatales, aún no se dan las transformaciones necesarias de las lógicas institucionales y de los operadores que estimulen la participación de NNA en el ámbito escolar. Esto se visualiza en la ausencia de análisis cuali de los contenidos de las acc. y la falta de ftes estadísticas específicas, que muestren la orientac.de los contenidos en los principios de la protecc.integral. Estos presupuestos plantean interrogantes que delimitan el problema de investigación: ¿cómo se construye y reconstruye el ejercicio de la ciudadanía a través de la participación de los NNA, en su paso por la escuela, y cuáles son las lógicas institucionales que habilitan u obstaculizan ese ejercicio? Y ¿cuáles son los recursos institucionales que permitan que los programas y acciones redunden en el ejercicio efectivo de los derechos?.Obj.gral: Describir, analizar e interpretar la progresividad en el ejercicio de los derechos de participación e informacióin que tienen los adolescentes en escuelas secundarias de la cd de Cba, durante 2005 / 2010, para promover espacios públicos de construcción de ciudadanía. Se analizarán tres escuelas de Córdoba, escuela pública provincial, púb. nacional y privada. Obj. Espec.: Analizar las prácticas participativas formales e informales en las escuelas seleccionadas.- Aplicar indicadores cuanti y cualitativos del “Sistema de Indicadores para los derechos de la Infancia” Describir y analizar los recursos materiales y humanos. Elaborar y proponer procedim. para la confec. de registros de datos estadísticos - Elaborar y proponer lineamientos para la elaborac.e implementac.de acciones. Diseñar herramientas de difusión sobre los ds de participación e información.Esta investigac. es de carácter descriptivo e interpretativo, analizará diferentes ftes de informac.con técnicas cuanti y cualitativas, durante período la promulgación de la Ley 26061/05 y la adhesión prov. 9396/07. Se tomarán del Sistema de Indicadores, el derecho a la educación, el tema transversal “Acceso a la información y participación”, y las categorías de análisis “Recepción del Derecho y Capacidades estatales”. Se trabajaran indicadores cuanti y señales de progreso (cualitativos): estructurales, proceso y resultados. Serán analizados los Programas implementados durante el período de estudio. Estrategias cuali observac. participante, entrevistas, grupos focales, talleres de sensibilización, etc .Otras ftes de info: doc. institucionales, registros, evaluac, contenidos de programas y campañas y de difusión, prensa escrita, legislaciones, etc. La info se analizará a través Programa Atlas Ti, y del análisis estadístico. Algunos resultados esperados: Evaluac.y ajuste del Sistema de indicadores, la sensibilizac. desde el EF de autorid. escol. para la formulac. de planes y programas para el monitoreo adecuado de los mismos y para la rendic. de ctas de su gestión. Estimular la participac. de NNA en la escuela. Realizac.de documental. Brindar herramientas al Edo para superv de la aplicación progresiva del ejercicio de los derechos de participación e información de NNA Promov la continua evaluac. de los programas y acc.desde el ED para estimular el reconoc. de la nec.de ajuste de la política. The issue of children from the rights focus implies a reading of the rights in which children and adolescents are the holders and the state actions that are implemented to enable the exercise of them. This perspective requires understanding the contents of the public policies, the participation level that is assigned, and the senses that they take in terms of rights progressivity of. The conception changes about children since the International Convention on the Rights of the Child and legislative changes challenge to the State and society to modify hegemony vision. Our hypothesis revolves around the following considerations: there have been some public policies and state actions changes, but they not turn out, yet, transformations in logical institutional and actors whose are encourages children participation in school. This could be reflects in the absence of qualitative analysis in the actions contents and the lack of sources specific statistics, that will be showing the control of the principal contents of integral protection. These, raise the questions that delimit our problem research: how is built citizenship exercise through children and adolescent’s participation in the school, and what are the institutional logical that empowers or turns difficult that exercise? And What are the institutional resources that make possible the effective exercise of the rights, through different programs and actions?. General Objective: To describe, analyze and interpret exercise progressivity participation and information rights that have the adolescents in secondary schools in Córdoba City during 2005 / 2010, in order to promote public spaces for the construction of citizenship. It will analyze three schools in Cordoba, provincial public school, national public school and private school. . Obj. Specifics: To analyze the formal and informal participative practices in the schools selected. - To apply quantitative and qualitative indicators of the “Indicators System for Infa

Assessing Strategies for Heart Failure with Preserved Ejection Fraction at the Outpatient Clinic

Background: Heart failure with preserved ejection fraction (HFPEF) is the most common form of heart failure (HF), its diagnosis being a challenge to the outpatient clinic practice. Objective: To describe and compare two strategies derived from algorithms of the European Society of Cardiology Diastology Guidelines for the diagnosis of HFPEF. Methods: Cross-sectional study with 166 consecutive ambulatory patients (67.9±11.7 years; 72% of women). The strategies to confirm HFPEF were established according to the European Society of Cardiology Diastology Guidelines criteria. In strategy 1 (S1), tissue Doppler echocardiography (TDE) and electrocardiography (ECG) were used; in strategy 2 (S2), B-type natriuretic peptide (BNP) measurement was included. Results: In S1, patients were divided into groups based on the E/E'ratio as follows: GI, E/E'> 15 (n = 16; 9%); GII, E/E'8 to 15 (n = 79; 48%); and GIII, E/E'< 8 (n = 71; 43%). HFPEF was confirmed in GI and excluded in GIII. In GII, TDE [left atrial volume index (LAVI) ≥ 40 mL/m2; left ventricular mass index LVMI) > 122 for women and > 149 g/m2 for men] and ECG (atrial fibrillation) parameters were assessed, confirming HFPEF in 33 more patients, adding up to 49 (29%). In S2, patients were divided into three groups based on BNP levels. GI (BNP > 200 pg/mL) consisted of 12 patients, HFPEF being confirmed in all of them. GII (BNP ranging from 100 to 200 pg/mL) consisted of 20 patients with LAVI > 29 mL/m2, or LVMI ≥ 96 g/m2 for women or ≥ 116 g/m2 for men, or E/E'≥ 8 or atrial fibrillation on ECG, and the diagnosis of HFPEF was confirmed in 15. GIII (BNP < 100 pg/mL) consisted of 134 patients, 26 of whom had the diagnosis of HFPEF confirmed when GII parameters were used. Measuring BNP levels in S2 identified 4 more patients (8%) with HFPEF as compared with those identified in S1. Conclusion: The association of BNP measurement and TDE data is better than the isolated use of those parameters. BNP can be useful in identifying patients whose diagnosis of HF had been previously excluded based only on TDE findings.

Development of CBCT-based prostate setup correction strategies and impact of rectal distension.

BACKGROUND: Cone-beam computed tomography (CBCT) image-guided radiotherapy (IGRT) systems are widely used tools to verify and correct the target position before each fraction, allowing to maximize treatment accuracy and precision. In this study, we evaluate automatic three-dimensional intensity-based rigid registration (RR) methods for prostate setup correction using CBCT scans and study the impact of rectal distension on registration quality. METHODS: We retrospectively analyzed 115 CBCT scans of 10 prostate patients. CT-to-CBCT registration was performed using (a) global RR, (b) bony RR, or (c) bony RR refined by a local prostate RR using the CT clinical target volume (CTV) expanded with 1-to-20-mm varying margins. After propagation of the manual CT contours, automatic CBCT contours were generated. For evaluation, a radiation oncologist manually delineated the CTV on the CBCT scans. The propagated and manual CBCT contours were compared using the Dice similarity and a measure based on the bidirectional local distance (BLD). We also conducted a blind visual assessment of the quality of the propagated segmentations. Moreover, we automatically quantified rectal distension between the CT and CBCT scans without using the manual CBCT contours and we investigated its correlation with the registration failures. To improve the registration quality, the air in the rectum was replaced with soft tissue using a filter. The results with and without filtering were compared. RESULTS: The statistical analysis of the Dice coefficients and the BLD values resulted in highly significant differences (p<10(-6)) for the 5-mm and 8-mm local RRs vs the global, bony and 1-mm local RRs. The 8-mm local RR provided the best compromise between accuracy and robustness (Dice median of 0.814 and 97% of success with filtering the air in the rectum). We observed that all failures were due to high rectal distension. Moreover, the visual assessment confirmed the superiority of the 8-mm local RR over the bony RR. CONCLUSION: The most successful CT-to-CBCT RR method proved to be the 8-mm local RR. We have shown the correlation between its registration failures and rectal distension. Furthermore, we have provided a simple (easily applicable in routine) and automatic method to quantify rectal distension and to predict registration failure using only the manual CT contours.

Three essays on the psychology of investment and financial markets

Préface My thesis consists of three essays where I consider equilibrium asset prices and investment strategies when the market is likely to experience crashes and possibly sharp windfalls. Although each part is written as an independent and self contained article, the papers share a common behavioral approach in representing investors preferences regarding to extremal returns. Investors utility is defined over their relative performance rather than over their final wealth position, a method first proposed by Markowitz (1952b) and by Kahneman and Tversky (1979), that I extend to incorporate preferences over extremal outcomes. With the failure of the traditional expected utility models in reproducing the observed stylized features of financial markets, the Prospect theory of Kahneman and Tversky (1979) offered the first significant alternative to the expected utility paradigm by considering that people focus on gains and losses rather than on final positions. Under this setting, Barberis, Huang, and Santos (2000) and McQueen and Vorkink (2004) were able to build a representative agent optimization model which solution reproduced some of the observed risk premium and excess volatility. The research in behavioral finance is relatively new and its potential still to explore. The three essays composing my thesis propose to use and extend this setting to study investors behavior and investment strategies in a market where crashes and sharp windfalls are likely to occur. In the first paper, the preferences of a representative agent, relative to time varying positive and negative extremal thresholds are modelled and estimated. A new utility function that conciliates between expected utility maximization and tail-related performance measures is proposed. The model estimation shows that the representative agent preferences reveals a significant level of crash aversion and lottery-pursuit. Assuming a single risky asset economy the proposed specification is able to reproduce some of the distributional features exhibited by financial return series. The second part proposes and illustrates a preference-based asset allocation model taking into account investors crash aversion. Using the skewed t distribution, optimal allocations are characterized as a resulting tradeoff between the distribution four moments. The specification highlights the preference for odd moments and the aversion for even moments. Qualitatively, optimal portfolios are analyzed in terms of firm characteristics and in a setting that reflects real-time asset allocation, a systematic over-performance is obtained compared to the aggregate stock market. Finally, in my third article, dynamic option-based investment strategies are derived and illustrated for investors presenting downside loss aversion. The problem is solved in closed form when the stock market exhibits stochastic volatility and jumps. The specification of downside loss averse utility functions allows corresponding terminal wealth profiles to be expressed as options on the stochastic discount factor contingent on the loss aversion level. Therefore dynamic strategies reduce to the replicating portfolio using exchange traded and well selected options, and the risky stock.

Uptake of new treatment strategies for deep vein thrombosis: an international audit.

OBJECTIVE: Study of the uptake of new medical technologies provides useful information on the transfer of published evidence into usual practice. We conducted an audit of selected hospitals in three countries (Canada, France, and Switzerland) to identify clinical predictors of low-molecular-weight (LMW) heparin use and outpatient treatment, and to compare the pace of uptake of these new therapeutic approaches across hospitals. DESIGN: Historical review of medical records. SETTING AND PARTICIPANTS: We reviewed the medical records of 3043 patients diagnosed with deep vein thrombosis (DVT) in five Canadian, two French, and two Swiss teaching hospitals from 1994 to 1998. Measures. We explored independent clinical variables associated with LMW heparin use and outpatient treatment, and determined crude and adjusted rates of LMW heparin use and outpatient treatment across hospitals. RESULTS: For the years studied, the overall rates of LMW heparin use and outpatient treatment in the study sample were 34.1 and 15.8%, respectively, with higher rates of use in later years. Many comorbidities were negatively associated with outpatient treatment, and risk-adjusted rates of use of these new approaches varied significantly across hospitals. CONCLUSION: There has been a relatively rapid uptake of LMW heparins and outpatient treatment for DVT in their early years of availability, but the pace of uptake has varied considerably across hospitals and countries.

Monetary policy strategies, financial institutions and financial markets in the Middle East and North Africa: an overview

Three polar types of monetary architecture are identified together with the institutional and market infrastructure required for each type and the kinds of monetary policy feasible in each case: a ‘basic’ architecture where there is little or no financial system as such but an elementary central bank which is able to fix the exchange rate, as a substitute for a proper monetary policy; a ‘modern’ monetary architecture with developed banks, financial markets and central bank where policy choices include types of inflation targeting; and an ‘intermediate’ monetary architecture where less market-based monetary policies involving less discretion are feasible. A range of data is used to locate the various MENA countries with respect to these polar types. Five countries (Iran, Libya, Sudan, Syria and Yemen) are identified as those with the least developed monetary architecture, while Bahrain and Jordan are identified as the group at the other end of the spectrum, reaching beyond the intermediate polar type in some dimensions but not others. The countries in between vary on different dimensions but all lie between basic and intermediate architectures. The key general findings are that the MENA countries are both less differentiated and less ‘developed’ than might have been expected. The paper ends by calling for research on the costs and benefits of different types of monetary architecture.

Motion compensation strategies in magnetic resonance imaging.

Image quality in magnetic resonance imaging (MRI) is considerably affected by motion. Therefore, motion is one of the most common sources of artifacts in contemporary cardiovascular MRI. Such artifacts in turn may easily lead to misinterpretations in the images and a subsequent loss in diagnostic quality. Hence, there is considerable research interest in strategies that help to overcome these limitations at minimal cost in time, spatial resolution, temporal resolution, and signal-to-noise ratio. This review summarizes and discusses the three principal sources of motion: the beating heart, the breathing lungs, and bulk patient movement. This is followed by a comprehensive overview of commonly used compensation strategies for these different types of motion. Finally, a summary and an outlook are provided.

Large multi-gene phylogenetic trees of the grasses (Poaceae): progress towards complete tribal and generic level sampling.

In this paper we included a very broad representation of grass family diversity (84% of tribes and 42% of genera). Phylogenetic inference was based on three plastid DNA regions rbcL, matK and trnL-F, using maximum parsimony and Bayesian methods. Our results resolved most of the subfamily relationships within the major clades (BEP and PACCMAD), which had previously been unclear, such as, among others the: (i) BEP and PACCMAD sister relationship, (ii) composition of clades and the sister-relationship of Ehrhartoideae and Bambusoideae + Pooideae, (iii) paraphyly of tribe Bambuseae, (iv) position of Gynerium as sister to Panicoideae, (v) phylogenetic position of Micrairoideae. With the presence of a relatively large amount of missing data, we were able to increase taxon sampling substantially in our analyses from 107 to 295 taxa. However, bootstrap support and to a lesser extent Bayesian inference posterior probabilities were generally lower in analyses involving missing data than those not including them. We produced a fully resolved phylogenetic summary tree for the grass family at subfamily level and indicated the most likely relationships of all included tribes in our analysis.

Three-year-olds' attachment play narratives and their associations with internalizing problems

Representational strategies of emotion regulation during play are believed to protect children against behaviour problems. Yet, before the age of 4, it appears that children rely more on their attachment figure than on representational strategies to assuage distress. The study was aimed at testing whether 3-year-olds' narrative features during the Attachment Story Completion Task (ASCT) could predict concurrent internalizing problems assessed by the mothers' and fathers' ratings of the child, using the Child Behaviour Checklist Regression analyses including gender, IQ, socio-economic status and ASCT dimensions revealed that representations of supportive caregiving predicted mother-reported internalizing problems (negative association), whereas positive resolution and attachment strategies (security, deactivation, hyperactivation, disorganization) did not. Results were interpreted with reference to Bowlby's hypotheses regarding the aetiology of depression and anxiety disorders. (PsycINFO Database Record (c) 2007 APA, all rights reserved)

Generic drugs in Spain: price competition vs. moral hazard

This paper examines competition between generic and brand-name drugs in the regulated Spanish pharmaceutical market. A nested logit demand model is specified for the three most consumed therapeutic subgroups in Spain: statins (anticholesterol), selective serotonin reuptake inhibitors (antidepressants) and proton pump inhibitors (antiulcers). The model is estimated with instrumental variables from a panel of monthly prescription data from 1999 to 2005. The dataset distinguishes between three different levels of patients’ copayments within the prescriptions and the results show that the greater the level of insurance that the patient has (and therefore the lower the patient’s copayment), the lower the proportion of generic prescriptions made by physicians. It seems that the low level of copayment has delayed the penetration of generics into the Spanish market. Additionally, the estimation of the demand model suggests that the substitution rules and promotional efforts associated with the reference pricing system have increased generic market share, and that being among the first generic entrants has an additional positive effect.

Determinants of generic drug substitution in Switzerland.

Background: Since generic drugs have the same therapeutic effect as the original formulation but at generally lower costs, their use should be more heavily promoted. However, a considerable number of barriers to their wider use have been observed in many countries. The present study examines the influence of patients, physicians and certain characteristics of the generics' market on generic substitution in Switzerland.Methods: We used reimbursement claims' data submitted to a large health insurer by insured individuals living in one of Switzerland's three linguistic regions during 2003. All dispensed drugs studied here were substitutable. The outcome (use of a generic or not) was modelled by logistic regression, adjusted for patients' characteristics (gender, age, treatment complexity, substitution groups) and with several variables describing reimbursement incentives (deductible, co-payments) and the generics' market (prices, packaging, co-branded original, number of available generics, etc.).Results: The overall generics' substitution rate for 173,212 dispensed prescriptions was 31%, though this varied considerably across cantons. Poor health status (older patients, complex treatments) was associated with lower generic use. Higher rates were associated with higher out-of-pocket costs, greater price differences between the original and the generic, and with the number of generics on the market, while reformulation and repackaging were associated with lower rates. The substitution rate was 13% lower among hospital physicians. The adoption of the prescribing practices of the canton with the highest substitution rate would increase substitution in other cantons to as much as 26%.Conclusions: Patient health status explained a part of the reluctance to substitute an original formulation by a generic. Economic incentives were efficient, but with a moderate global effect. The huge interregional differences indicated that prescribing behaviours and beliefs are probably the main determinant of generic substitution.