Quantitative Assessment of Emphysema Severity in Histological Lung Analysis

Published onlineEmphysema is a characteristic component of chronic obstructive pulmonary disease (COPD), which has been pointed out as one of the main causes of mortality for the next years. Animal models of emphysema are employed to study the evolution of this disease as well as the effect of treatments. In this context, measures such as the mean linear intercept (Lm) and the equivalent diameter (d) have been proposed to quantify the airspace enlargement associated with emphysematous lesions in histological sections. The parameter D2 , which relates the second and the third moments of the variable d , has recently shown to be a robust descriptor of airspace enlargement. However, the value of D2 does not provide a direct evaluation of emphysema severity. In our research, we suggest a Bayesian approach to map D2 onto a novel emphysema severity index (SI) reflecting the probability for a lung area to be emphysematous. Additionally, an image segmentation procedure was developed to compute the severity map of a lung section using the SI function. Severity maps corresponding to 54 lung sections from control mice, mice induced with mild emphysema and mice induced with severe emphysema were computed, revealing differences between the distribution of SI in the three groups. The proposed methodology could then assist in the quantification of emphysema severity in animal models of pulmonary disease.This work has been partly funded by the grants ‘‘MINECO DPI2012-38090-C03-02’’ and ‘‘TEC2013-48552-C2-1-R’’ from the Spanish Ministry of Economy and CompetitivenessPublicad

Detecting Multiple Breaks in Financial Market Volatility Dynamics

The paper evaluates the performance of several recently proposed tests for structural breaks in conditional variance dynamics of asset returns. The tests apply to the class of ARCH and SV type processes as well as data-driven volatility estimators using high-frequency data. In addition to testing for the presence of breaks, the statistics identify the number and location of multiple breaks. We study the size and power of the new test for detecting breaks in the second conditional variance under various realistic univariate heteroskedastic models, change-point hypotheses and sampling schemes. The paper concludes with an empirical analysis using data from the stock and FX markets for which we find multiple breaks associated with the Asian and Russian financial crises. These events resulted in changes in the dynamics of volatility of asset returns in the samples prior and post the breaks.change-point, break dates, ARCH, high-frequency data.

Remote sensing applications to resource problems in South Dakota

The author has identified the following significant results. Change in the vegetative structure was taking place in the Black Hills. Temporal analysis of the areal extent of open meadows was accomplished using black and white and color infrared aerial photography. A reduction of nearly 1100 hectares of open meadows was determined using photointerpretation. Techniques were developed for the management of meandering lakes, including use of LANDSAT imagery for continuous monitoring, classification of hydrophytes on low altitude CIR imagery, and planning and evaluation of improvements and multiple uses on aerial photography and photo mosaics. LANDSAT data were analyzed statistically from small and entire study scene areas to determine the effect of soils stratifications of corn signatures. Band 5 early season and band 7 later season recorded the strongest evidence of the influence of soils on corn signatures. Significant strata were determined by a multiple range test

Computational Methods for Task-Directed Sensor Data Fusion and Sensor Planning

In this paper, we consider the problem of task-directed information gathering. We first develop a decision-theoretic model of task-directed sensing in which sensors are modeled as noise-contaminated, uncertain measurement systems and sensing tasks are modeled by a transformation describing the type of information required by the task, a utility function describing sensitivity to error, and a cost function describing time or resource constraints on the system. This description allows us to develop a standard conditional Bayes decision-making model where the value of information, or payoff, of an estimate is defined as the average utility (the expected value of some function of decision or estimation error) relative to the current probability distribution and the best estimate is that which maximizes payoff. The optimal sensor viewing strategy is that which maximizes the net payoff (decision value minus observation costs) of the final estimate. The advantage of this solution is generality--it does not assume a particular sensing modality or sensing task. However, solutions to this updating problem do not exist in closed-form. This, motivates the development of an approximation to the optimal solution based on a grid-based implementation of Bayes\u27 theorem. We describe this algorithm, analyze its error properties, and indicate how it can be made robust to errors in the description of sensors and discrepancies between geometric models and sensed objects. We also present the results of this fusion technique applied to several different information gathering tasks in simulated situations and in a distributed sensing system we have constructed

PadChest: A large chest x-ray image dataset with multi-label annotated reports

We present a labeled large-scale, high resolution chest x-ray dataset for the automated exploration of medical images along with their associated reports. This dataset includes more than 160,000 images obtained from 67,000 patients that were interpreted and reported by radiologists at Hospital San Juan Hospital (Spain) from 2009 to 2017, covering six different position views and additional information on image acquisition and patient demography. The reports were labeled with 174 different radiographic findings, 19 differential diagnoses and 104 anatomic locations organized as a hierarchical taxonomy and mapped onto standard Unified Medical Language System (UMLS) terminology. Of these reports, 27% were manually annotated by trained physicians and the remaining set was labeled using a supervised method based on a recurrent neural network with attention mechanisms. The labels generated were then validated in an independent test set achieving a 0.93 Micro-F1 score. To the best of our knowledge, this is one of the largest public chest x-ray database suitable for training supervised models concerning radiographs, and the first to contain radiographic reports in Spanish. The PadChest dataset can be downloaded from http://bimcv.cipf.es/bimcv-projects/padchest/

Utilization of ERTS-1 for appraising changes in continental migratory bird habitat

The author has identified the following significant results. Information on numbers, distribution, and quality of wetlands in the breeding range of migratory waterfowl is important for the management of this wildlife resource. Using computer processing of data gathered by the ERTS-1 multispectral scanner, techniques for obtaining indices of annual waterfowl recruitment, and habitat quality are examined. As a primary task, thematic maps and statistics relating to open surface water were produced. Discrimination of water was based upon water's low apparent radiance in a single, near-infrared waveband. An advanced technique using multispectral information for discerning open water at a level of detail finer than the virtual resolution of the data was also successfully tested. In another related task, vegetation indicators were used for detecting conditions of latent or occluded water and upland habitat characteristics

An integrated study of earth resources in the State of California based on ERTS-1 and supporting aircraft data, volume 1

There are no author-identified significant results in this report

Intravascular Ultrasound

Intravascular ultrasound (IVUS) is a cardiovascular imaging technology using a specially designed catheter with a miniaturized ultrasound probe for the assessment of vascular anatomy with detailed visualization of arterial layers. Over the past two decades, this technology has developed into an indispensable tool for research and clinical practice in cardiovascular medicine, offering the opportunity to gather diagnostic information about the process of atherosclerosis in vivo, and to directly observe the effects of various interventions on the plaque and arterial wall. This book aims to give a comprehensive overview of this rapidly evolving technique from basic principles and instrumentation to research and clinical applications with future perspectives

Investigating the variance in wing melanization pattern among colour dimorphic males of the wood tiger moth (Arctia plantaginis)

Nel mio lavoro di tesi è stata analizzata la variabilità nel pattern di melanizzazione alare osservabile nei maschi, dicromatici, della falena Arctia plantaginis. La specie è un interessante soggetto per lo studio di teorie sulla selezione dei caratteri per via delle interazioni ecologiche basate sulla colorazione alare: A. plantaginis una specie aposematica che presenta un polimorfismo maschile per la colorazione delle ali inferiori (gialle o bianche), mantenuto dal trade-off di selezione naturale e sessuale. Il campione utilizzato proviene da una popolazione allevata in serra presso l’università di Jyväskylä (FI). L’obiettivo primario è quello di verificare la presenza di variabilità nella deposizione del pigmento nero sulle ali e se questa possa essere correlata all’espressione di uno specifico colore nei maschi. Per fare ciò sono state fotografate le ali di 140 maschi, con genotipo noto per il locus della colorazione alare. L’analisi morfometrica di ali anteriori e posteriori separatamente è stata eseguita in R utilizzando Patternize e Recolorize, due pacchetti che permettono la rilevazione automatica e l’analisi di variabilità dei pattern cromatici. In secondo luogo, è stata valutata la correlazione dell’estensione del pattern sia con il colore delle ali posteriori, che con il genotipo del locus del colore. Infine, è stata valutata l’adeguatezza della classificazione arbitrariamente binaria del fenotipo “grado di melanizzazione” (plus, “+”; minus, “-”), utilizzata in laboratorio e basata sulle ali posteriori. Le analisi hanno permesso di accertare che la variazione del pattern deriva principalmente da differenze in abbondanza di pigmento sintetizzato, di confermare precedenti ipotesi sulla presenza di una componente genetica, seppur limitata, nella variabilità del tratto, e di rilevare una lieve correlazione tra colore e melanizzazione. La distribuzione del campione, bimodale, in esame ha dimostrato la correttezza della suddivisione in due categorie di melanizzazione, ma è stata evidenziata una perdita di informazioni sull’ampia variabilità delle ali posteriori di individui più melanici (plus).In my thesis work the variability in the pattern of wing melanization observable in the males, dichromatic, of the moth Arctia plantaginis was analyzed. The species is an interesting case study to test theories on selection of traits thanks to its multiple ecological interactions based on wing coloration: A. plantaginis is an aposematic species that presents a male polymorphism in hindwing colouration (yellow or white), maintained by the trade-off of natural and sexual selection. The sample used comes from a stock population reared for many generations at the University of Jyväskylä (FI). The central aim is to confirm the presence of variability in the deposition of black pigment on the wings and test whether this can be related to the expression of a specific hindwing colour in males. To do this, the wings of 140 males were photographed, with genotype known for the locus of wing coloration. The wing morphometric analysis, of forewing and hindwing separately, was performed in R using Patternize and Recolorize, two packages that allow automatic detection and analysis of colour patterns variability. In second place, the correlation of pattern extension with both hindwing colour and colour locus genotype was evaluated. Finally, I assessed the adequacy of the arbitrarily binary classification (plus, minus) of the trait "degree of melanization", adopted in the laboratory and based on hindwings. The analyses allowed to ascertain that the variation in the melanic pattern derives mainly from differences in the abundance of synthesized pigment, to confirm previous hypotheses on the presence of a genetic component, albeit limited, in the variability of the trait, and to detect a slight correlation between hindwing colour and melanization. The melanization categories found support in the distribution of the sample under examination, however, within the category of higher melanization there was a greater variability in melanization that cannot be exploited by this binary subdivision

Estimation of distribution algorithms in logistics : Analysis, design, and application

This thesis considers the analysis, design and application of Estimation of Distribution Algorithms (EDA) in Logistics. It approaches continouos nonlinear optimization problems (standard test problems and stochastic transportation problems) as well as location problems, strategic safety stock placement problems and lotsizing problems. The thesis adds to the existing literature by proposing theoretical advances for continuous EDAs and practical applications of discrete EDAs. Thus, it should be of interest for researchers from evolutionary computation, as well as practitioners that are in need of efficient algorithms for the above mentioned problems