Improving Semantic Segmentation of 3D Medical Images on CNNs

International audienceA neural network is a mathematical model that is able to perform a task automatically or semi-automatically after learning the human knowledge that we provided. Moreover, a Convolutional Neural Network (CNN) is a type of neural network that has shown to efficiently learn tasks related to the area of image analysis, such as image segmentation, whose main purpose is to find regions or separable objects within an image. A more specific type of segmentation, called semantic segmentation, guarantees that each region has a semantic meaning by giving it a label or class. Since CNNs can automate the task of image semantic segmentation, they have been very useful for the medical area, applying them to the segmentation of organs or abnormalities (tumors). This work aims to improve the task of binary semantic segmentation of volumetric medical images acquired by Magnetic Resonance Imaging (MRI) using a pre-existing Three-Dimensional Convolutional Neural Network (3D CNN) architecture. We propose a formulation of a loss function for training this 3D CNN, for improving pixel-wise segmentation results. This loss function is formulated based on the idea of adapting a similarity coefficient, used for measuring the spatial overlap between the prediction and ground truth, and then using it to train the network. As contribution, the developed approach achieved good performance in a context where the pixel classes are imbalanced. We show how the choice of the loss function for training can affect the final quality of the segmentation. We validate our proposal over two medical image semantic segmentation datasets and show comparisons in performance between the proposed loss function and other pre-existing loss functions used for binary semantic segmentation

Hackathon als Open Innovation in der öffentlichen Verwaltung: Eine qualitative Untersuchung am Beispiel der Data Hackdays Bern

Der vorliegende Beitrag diskutiert die Innovationsmetode „Hackathon“ im Anwendungskontext des öffentlichen Sektors. Abgeleitet aus den Konzepten Open Government und Open Innovation wird aus der Literatur ein Überblick gegeben werden, inwieweit Innovationswettbewerbe wie ein Hackathon geeignet sind, Innovationsideen aus der Gesellschaft in die Verwaltung zu bringen und die digitale Transformation des öffentlichen Sektors zu unterstützen. Anschließend werden die Ergebnisse präsentiert, welche im Nachgang zu den erstmals vom Kanton Bern initiierten Data Hackdays 2021 geführt worden waren. Der Hackathon hat insbesondere das Potenzial, dass in der Vorbereitung gewohnte Arbeitsweisen und Routinen verlassen werden und am Anlass selber eine Auseinandersetzung mit einer interessierten Community ermöglicht wird. Die Resultate zeigen auch Schwierigkeiten in der Vorbereitung auf, welche allerdings mit zunehmender Erfahrung zu bewältigen sind

Characterization of Tonsilloliths in Cone Beam Computed Tomography Scans of Patients Treated at the Teaching Dental Center of Universidad Peruana Cayetano Heredia, Lima, Peru, 2018-2021

The origin of tonsilloliths is related to a history of recurring tonsillitis or tonsillar abscesses during childhood. This study investigates the frequency, number, location, size, shape, as well as the age and sex of the patients, in order to establish parameters for the characteristics and statistical data that contribute to the early detection of this condition. Objective: To determine the characteristics of tonsilloliths in cone beam computed tomography (CBCT) scans of patients treated at the Teaching Dental Center of Universidad Peruana Cayetano Heredia. Material and methods: An observational, descriptive, retrospective, cross-sectional study was conducted, analyzing all CBCT scans from the period 2018-2021. Out of the total scans, 200 met the selection criteria. The chi-square test was used to establish relationships between variables, with a 95% confidence interval and a significance level of 0.05. Results: Among the 200 CBCT scans analyzed, 49 (24.5 %) showed tonsilloliths. Among these, 39 (19.5 %) belonged to female patients, while 32 (16 %) were patients older than 50 years. A total of 21 (42.86 %) scans presented a single tonsillolith, and 30 (61.2%) were located unilaterally. The analysis revealed a total count of 124 tonsilloliths, with 64 (51.6%) located on the right side. Furthermore, 88 (71.96 %) of the tonsilloliths exhibited a punctiform shape, with an average size of 1.68 mm. Conclusions: Tonsilloliths demonstrated a high frequency, primarily among females from the fifth decade of life, with sizes less than 2 mm, predominantly punctiform in shape, and located unilaterally.El origen de los tonsilolitos está relacionado con antecedentes de amigdalitis en repetidas ocasiones durante la infancia o de abscesos amigdalares. El presente trabajo investigó la frecuencia, el número, la localización, el tamaño, la forma, así como la edad y el sexo de los pacientes, para aportar parámetros de las características y los datos estadísticos que contribuyan a la detección temprana de esta patología. Objetivo: Determinar las características de los tonsilolitos en tomografías computarizadas de haz cónico (TCHC) de pacientes atendidos en el Centro Dental Docente de la Universidad Peruana Cayetano Heredia. Material y métodos: Se realizó un estudio observacional, descriptivo, retrospectivo, transversal, donde se analizaron todas las TCHC del período 2018-2021, de las cuales 200 cumplieron con los criterios de selección. Para relacionar las variables se utilizó la prueba de chi cuadrado con un intervalo de confianza de 95 % y un nivel de significancia de 0,05. Resultados: De las 200 TCHC analizadas, 49 (24,5 %) presentaron tonsilolitos, 39 (19,5 %) pertenecieron al sexo femenino, 32 (16 %) pertenecieron a pacientes mayores de 50 años, 21 (42,86 %) presentaron un solo tonsilolito, y 30 (61,2 %) se localizaron unilateralmente. Se contabilizaron 124 tonsilolitos en total; de los cuales, 64 (51,6 %) se localizaron en el lado derecho, 88 (71,96 %) fueron puntiformes, y su tamaño promedio fue de 1,68 mm. Conclusiones: Los tonsilolitos presentaron una alta frecuencia, principalmente en el sexo femenino, a partir de la quinta década de la vida, con un tamaño menor a 2 mm, predominando los puntiformes y la ubicación unilateral.A origem dos tonsilólitos está relacionada a um histórico de tonsilites repetidas na infância ou abscessos tonsilares. O presente estudo investigou a frequência, o número, a localização, o tamanho, a forma, a idade e o sexo dos pacientes, a fim de fornecer parâmetros característicos e dados estatísticos que contribuam para a detecção precoce dessa patologia. Objetivo: Determinar as características dos tonsilólitos em exames de tomografia computadorizada de feixe cônico (TCHC) de pacientes atendidos no Centro Dental Docente da Universidad Peruana Cayetano Heredia. Material e métodos: Foi realizado um estudo observacional, descritivo, retrospectivo e transversal, no qual foram analisados todos os TCHC do período 2018-2021, dos quais 200 atenderam aos critérios de seleção. O teste qui-quadrado foi usado para relacionar as variáveis, com um intervalo de confiança de 95% e um nível de significância de 0,05. Resultados: Dos 200 TCHC analisados, 49 (24,5%) apresentaram tonsilólitos, dos quais 39 (19,5%) pertenciam ao sexo feminino. Além disso, 32 (16%) pacientes tinham mais de 50 anos de idade, 21 (42,86%) possuíam apenas um tonsilólito, e 30 (61,2%) estavam localizados unilateralmente. Foram contabilizados um total de 124 tonsilólitos; desses, 64 (51,6%) estavam localizados no lado direito, 88 (71,96%) tinham forma puntiforme e um tamanho médio de 1,68 mm. Conclusões: Os tonsilólitos foram altamente prevalentes, principalmente em mulheres a partir da quinta década de vida, com tamanho inferior a 2 mm, predominantemente puntiformes e com localização unilateral

Antifungal prophylaxis with nebulized amphotericin-B in solid-organ transplant recipients with severe COVID-19: a retrospective observational study

Aspergillosis; COVID-19; ProphylaxisAspergilosis; COVID-19; ProfilaxisAspergilosi; COVID 19; ProfilaxiCOVID-19-associated pulmonary aspergillosis (CAPA) has emerged as a frequent complication in the intensive care unit (ICU). However, little is known about this life-threatening fungal superinfection in solid organ transplant recipients (SOTRs), including whether targeted anti-mold prophylaxis might be justified in this immunosuppressed population. We performed a multicentric observational retrospective study of all consecutive ICU-admitted COVID-19 SOTRs between August 1, 2020 and December 31, 2021. SOTRs receiving antifungal prophylaxis with nebulized amphotericin-B were compared with those without prophylaxis. CAPA was defined according the ECMM/ISHAM criteria. Sixty-four SOTRs were admitted to ICU for COVID-19 during the study period. One patient received antifungal prophylaxis with isavuconazole and was excluded from the analysis. Of the remaining 63 SOTRs, nineteen (30.2%) received anti-mold prophylaxis with nebulized amphotericin-B. Ten SOTRs who did not receive prophylaxis developed pulmonary mold infections (nine CAPA and one mucormycosis) compared with one who received nebulized amphotericin-B (22.7% vs 5.3%; risk ratio 0.23; 95%CI 0.032-1.68), but with no differences in survival. No severe adverse events related to nebulized amphotericin-B were recorded. SOTRs admitted to ICU with COVID-19 are at high risk for CAPA. However, nebulized amphotericin-B is safe and might reduce the incidence of CAPA in this high-risk population. A randomized clinical trial to confirm these findings is warranted.AR received a predoctoral research grant from the Instituto de Salud Carlos III, Spanish Ministry of Science, Innovation and Universities, (PFIS grant FI18/00183). This work was supported by the Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Economía, Industria y Competitividad, Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain. We thank CERCA Programme/Generalitat de Catalunya for institutional support

Análisis del ciclo de vigilancia tecnológica en las empresas del sector textil del centro sur de Caldas

En Colombia, la cadena textil-confección es prioritaria para el desarrollo de sectores de clase mundial.  En Caldas, esta cadena debe desarrollar habilidades para asegurar su posición en el mercado; para tal efecto, se requiere implementar herramientas de vigilancia tecnológica e inteligencia competitiva para conocer las tendencias del mercado y las nuevas tecnologías.   Este artículo es producto de una investigación de tipo descriptiva realizada en las empresas de la región centro sur de Caldas en la cual se analizaron las herramientas de  vigilancia tecnológica empleadas.  El estudio concluye que es necesario fortalecer algunas etapas del ciclo de vigilancia tecnológica, herramienta para mejorar la competitividad

Análisis del ciclo de vigilancia tecnológica en las empresas del sector textil del centro sur de Caldas

En Colombia, la cadena textil-confección es prioritaria para el desarrollo de sectores de clase mundial.  En Caldas, esta cadena debe desarrollar habilidades para asegurar su posición en el mercado; para tal efecto, se requiere implementar herramientas de vigilancia tecnológica e inteligencia competitiva para conocer las tendencias del mercado y las nuevas tecnologías.   Este artículo es producto de una investigación de tipo descriptiva realizada en las empresas de la región centro sur de Caldas en la cual se analizaron las herramientas de  vigilancia tecnológica empleadas.  El estudio concluye que es necesario fortalecer algunas etapas del ciclo de vigilancia tecnológica, herramienta para mejorar la competitividad

Mechanical Activation of Al-Oxyhydroxide Minerals – Physicochemical Changes, Reactivity and Relevance to Bayer Process

Overview of our research on ‘structure and reactivity’ of gibbsite and boehmite under varied conditions of mechanical activation, e.g. milling energy and presence of a second phase is presented. Bulk and surface changes induced in the solids by milling are characterized in terms of morphology, particle size distribution, specific surface area and nature of porosity, crystallite size and zeta potential. Results on enhanced amorphisation of gibbsite in presence of a second phase (quartz, hematite etc), changes in zeta potential of gibbsite due to loss of texture during milling and anomalous decrease in surface area of boehmite during milling are reported. Reactivity of the activated solids in sodium hydroxide and variation in thermal transformation temperatures is correlated with physicochemical characteristics of the samples and plausible explanation for the observed correlations presented. Significance of the results with specific reference to bauxite and alumina processing in Bayer process is highlighted

Multicomponent analysis of the tumour microenvironment reveals low CD8 T cell number, low stromal caveolin-1 and high tenascin-C and their combination as significant prognostic markers in non-small cell lung cancer

The complex interplay of the tumour microenvironment (TME) and its role in disease progression and response to therapy is poorly understood. The majority of studies to date focus on individual components or molecules within the TME and so lack the power correlative analysis. Here we have performed a multi-parameter analysis of the TME in 62 resectable non-small cell lung cancer (NSCLC) specimens detailing number and location of immune infiltrate, assessing markers of cancer-associated fibroblasts, caveolin-1 and tenascin-C, and correlating with clinicopathological details, as well as markers of disease progression such as epithelial-to-mesenchymal transition (EMT). The influence of individual parameters on overall survival was determined in univariate and multivariate analysis and the combination of risk factors and interplay between components analysed. Low numbers of CD8 T cells, low stromal levels of caveolin-1 or high levels of tenascin-C were significant prognostic markers of decreased overall survival in both univariate and multivariate analysis. Patients with two or more risk factors had dramatically reduced overall survival and those with all three a median survival of just 7.5 months. In addition, low levels of tumour E-cadherin correlated with reduced immune infiltrate into the tumour nests, possibly linking EMT to the avoidance of CD8 T cell control. The multicomponent approach has allowed identification of the dominant influences on overall survival, and exploration of the interplay between different components of the TME in NSCLC

Integration of decision support systems to improve decision support performance

Decision support system (DSS) is a well-established research and development area. Traditional isolated, stand-alone DSS has been recently facing new challenges. In order to improve the performance of DSS to meet the challenges, research has been actively carried out to develop integrated decision support systems (IDSS). This paper reviews the current research efforts with regard to the development of IDSS. The focus of the paper is on the integration aspect for IDSS through multiple perspectives, and the technologies that support this integration. More than 100 papers and software systems are discussed. Current research efforts and the development status of IDSS are explained, compared and classified. In addition, future trends and challenges in integration are outlined. The paper concludes that by addressing integration, better support will be provided to decision makers, with the expectation of both better decisions and improved decision making processes