Addition and cycloaddition reactions of allenyl cations with various cycloalka-1,3-dienes

Allenyl cations , generated from propargyl chlorides and zinc chloride give monocyclic adducts or [3+4] and [2+4] cycloaddition products with various cycloalka-1,3-dienes. The mode of addition depends on R and the ring size of the 1,3-dienes

Regular Inference over Recurrent Neural Networks as a Method for Black Box Explainability

Incluye bibliografía.El presente Desarrollo de Tesis explora el problema general de explicar el comportamiento de una red neuronal recurrente (RNN por sus siglas en inglés). El objetivo es construir una representación que mejore el entendimiento humano de las RNN como clasificadores de secuencias, con el propósito de proveer entendimiento sobre el proceso de decisión detrás de la clasificación de una secuencia como positiva o negativa, y a su vez, habilitar un mayor análisis sobre las mismas como por ejemplo la verificación formal basada en autómatas. Se propone en concreto, un algoritmo de aprendizaje automático activo para la construcción de un autómata finito determinístico que es aproximadamente correcto respecto a una red neuronal artificial

"An erring conscience is an absurdity": The later Kant on certainty, moral judgment and the infallibility of conscience

This article explores Kant’s view, found in several passages in his late writings on moral philosophy, that the verdicts of conscience are infallible. We argue that Kant’s infallibility claim must be seen in the context of a major shift in Kant’s views on conscience that took place around 1790 and that has not yet been sufficiently appreciated in the literature. This shift led Kant to treat conscience as an exclusively second-order capacity which does not directly evaluate actions, but one’s first-order moral judgments and deliberation. On the basis of this novel interpretation, we develop a new defence of Kant’s infallibility claim that draws on Kant’s account of the characteristic features of specifically moral judgments.publishedVersio

¿Cómo compartir datos de manera efectiva y privada?

Este trabajo analiza la problemática general de dar garantías de privacidad manteniendo niveles aceptables de utilidad predictiva cuando se comparten datos sensibles. En particular, se considera la situación en la cual varias organizaciones (públicas y/o privadas) comparten entre ellas y/o con terceros modelos entrenados con datos privados de cada una de ellas.Agencia Nacional de Investigación e Innovació

Toward Clinically Compatible Phase-Contrast Mammography

Phase-contrast mammography using laboratory X-ray sources is a promising approach to overcome the relatively low sensitivity and specificity of clinical, absorption-based screening. Current research is mostly centered on identifying potential diagnostic benefits arising from phase-contrast and dark-field mammography and benchmarking the latter with conventional state-of-the-art imaging methods. So far, little effort has been made to adjust this novel imaging technique to clinical needs. In this article, we address the key points for a successful implementation to a clinical routine in the near future and present the very first dose-compatible and rapid scan-time phase-contrast mammograms of both a freshly dissected, cancer-bearing mastectomy specimen and a mammographic accreditation phantom

Toward Clinically Compatible Phase-Contrast Mammography

Phase-contrast mammography using laboratory X-ray sources is a promising approach to overcome the relatively low sensitivity and specificity of clinical, absorption-based screening. Current research is mostly centered on identifying potential diagnostic benefits arising from phase-contrast and dark-field mammography and benchmarking the latter with conventional state-of-the-art imaging methods. So far, little effort has been made to adjust this novel imaging technique to clinical needs. In this article, we address the key points for a successful implementation to a clinical routine in the near future and present the very first dose-compatible and rapid scan-time phase-contrast mammograms of both a freshly dissected, cancer-bearing mastectomy specimen and a mammographic accreditation phantom

Assessment of intraductal carcinoma in situ (DCIS) using grating-based X-ray phase-contrast CT at conventional X-ray sources: An experimental ex-vivo study

Background The extent of intraductal carcinoma in situ (DCIS) is commonly underestimated due to the discontinuous growth and lack of microcalcifications. Specimen radiography has been established to reduce the rate of re-excision. However, the predictive value for margin assessment with conventional specimen radiography for DCIS is low. In this study we assessed the potential of grating-based phase-contrast computed tomography (GBPC-CT) at conventional X-ray sources for specimen tomography of DCIS containing samples. Materials and methods GBPC-CT was performed on four ex-vivo breast specimens containing DCIS and invasive carcinoma of non-specific type. Phase-contrast and absorption-based datasets were manually matched with corresponding histological slices as the standard of reference. Results Matching of CT images and histology was successful. GBPC-CT showed an improved soft tissue contrast compared to absorption-based images revealing more histological details in the same sections. Non-calcifying DCIS exceeding the invasive tumor could be correlated to areas of dilated bright ducts around the tumor. Conclusions GBPC-CT imaging at conventional X-ray sources offers improved depiction quality for the imaging of breast tissue samples compared to absorption-based imaging, allows the identification of diagnostically relevant tissue details, and provides full three-dimensional assessment of sample margins

An organometallic chimie douce approach to new Re(x)W(1-x)O3 phases

Re(x)W(1-x)O3.H2O and Re(x)W(1-x)O3 phases are prepared by a new organometallic chimie douce concept employing the organometallic precursor methyltrioxorhenium.Comment: 3 pages, 6 figures, submitted to Chem. Com

Antiretroviral tolerability and efficacy after switch to saquinavir in PI-experienced patients : 48-week analysis of the German Rainbow Cohort

Poster presentation: Purpose of the study The aim of the Rainbow Cohort is to assess the tolerability and efficacy of initiating treatment with, or switching treatment to the saquinavir (SQV) 500 mg film-coated tablet formulation. We present the final 48-week subgroup analysis of PI-experienced, but SQV-naïve patients. ..

Improved Diagnostics by Assessing the Micromorphology of Breast Calcifications via X-Ray Dark-Field Radiography

Breast microcalcifications play an essential role in the detection and evaluation of early breast cancer in clinical diagnostics. However, in digital mammography, microcalcifications are merely graded with respect to their global appearance within the mammogram, while their interior microstructure remains spatially unresolved and therefore not considered in cancer risk stratification. In this article, we exploit the sub-pixel resolution sensitivity of X-ray dark-field contrast for clinical microcalcification assessment. We demonstrate that the micromorphology, rather than chemical composition of microcalcification clusters (as hypothesised by recent literature), determines their absorption and small-angle scattering characteristics. We show that a quantitative classification of the inherent microstructure as ultra-fine, fine, pleomorphic and coarse textured is possible. Insights underlying the micromorphological nature of breast calcifications are verified by comprehensive high-resolution micro-CT measurements. We test the determined microtexture of microcalcifications as an indicator for malignancy and demonstrate its potential to improve breast cancer diagnosis, by providing a non-invasive tool for sub-resolution microcalcification assessment. Our results indicate that dark-field imaging of microcalcifications may enhance the diagnostic validity of current microcalcification analysis and reduce the number of invasive procedures