U. Fischer, F. Baum, S. Luftner-Nagel. Breast Cancer: Diagnostic Imaging and Therapeutic Guidance

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Macbeth, il bosco di Birnam e la responsabilità civile della p.a.

[Macbeth, the Birnam forest and the civil liability of the p.a.] Taking a cue from the now historic doctrinal debate about the analogy between the Birnam forest and the transformation of decisions of courts on civil liability, the article aims to compare civil liability of the public administration with some represented aspect in the Macbeth by Shakespeare

Measuring Dynamics of Scattering Centers in the Ocular Fundus

The study is focused on the analysis of the diffusing-wave-spectroscopy signalrecorded invivo on the ocular fundus of a rabbit eye. The motion of the scattered sites wasmeasured as a function of the pressure exerted by a Goldmann contact lens and during themoderate temperature increase induced by a therapeutic laser diode. Temporal fluctuations ofthe signal revel motion of molecules and thus changes in tissues temperature andchorioretinal blood velocity. Experimental results show the ability of the system to detectmotion of the scattering sites in the ocular fundus layers during variations of the ocularpressure and laser heating

Short-term planning of battery and hydrogen storage operation in electrical energy distribution systems

Orientadores: Luiz Carlos Pereira da Silva, Marcos Julio Rider Flores (1975)Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: O armazenamento de energia é considerado uma alternativa tecnológica para enfrentar a variabilidade da geração intermitente, efetuar a supressão do pico da demanda, estimular os mercados elétricos competitivos, entre outros desafios enfrentados pelos sistemas de distribuição de energia elétrica (SDEE). Esse trabalho apresenta a modelagem do planejamento da operação de curto prazo de uma rede de distribuição com a presença de armazenamento de energia e geração intermitente eólica e solar. Os armazenadores de energia consistem em baterias e armazenamento de hidrogênio. Nesse sentido, o modelo dos equipamentos busca aproximar-se da operação real a partir das restrições impostas e dos parâmetros comerciais utilizados. Assim, primeiramente propõe-se um modelo de programação não linear inteira mista (PNLIM). Dada a dificuldade em encontrar soluções através desse modelo, o mesmo é relaxado para um modelo de programação cônica de segunda ordem inteira mista (PCSOIM), implementando-o na linguagem de modelagem algébrica AMPL. Uma vez que o novo modelo é convexo, sua solução é encontrada com o auxílio do solver CPLEX®. Posteriormente, um sistema teste de 11 nós é utilizado para testar o modelo. Avaliam-se dois macro casos: o sistema simples (SS) e o sistema híbrido (SH). Um SS consiste em dispositivos de armazenamento em nós distintos, enquanto que um SH incorpora dispositivos de armazenamento diferentes em um mesmo nó. Nota-se que os dispositivos de armazenamento do SS e do SH são capazes de promover a redução dos picos de demanda no horário de ponta. Porém, para o SH, a profundidade de descarga (PDD) da bateria encontra-se limitada em 60, 45 e 40% nas diferentes análises, o que favorece a preservação da vida útil do equipamentoAbstract: Energy storage is considered a technological alternative to face the variability of intermittent generation, to realize the peak-shaving, stimulate the competitive electricity markets, among others challenges faced by modern electrical energy distribution systems (EEDS). This work introduces the modeling of short-term distribution network operation in the presence of energy storage, wind and solar intermittent generation. The energy storage devices are batteries and hydrogen storage. In this regard, the model of the devices aims to be close to the real operation based on the restrictions imposed and the commercial parameters used. Thus, firstly it was proposed a mixed-integer nonlinear programming (MINLP) model. Due to the difficulty of the solution of this model was elaborated a mixed-integer second-order cone programming (MISOCP). The model was implemented in an algebraic modeling language AMPL and once this model is convex, the solution is found with the support of CPLEX® solver. Posteriorly, a test system of 11-node is used to test the model. Then, two macro cases was evaluated: the simple system (SS) and the hybrid system (HS). A SS consists of energy storage devices placed in distinct nodes, whereas a HS incorporates different energy storage devices in the same node. It should be noted that SS and HS storage devices are capable of reducing demand peaks at peak times. However, for the HS, the battery depth of discharge (DoD) is limited in 60, 45, 40%, in the different analyzes, which favors the equipment lifespanMestradoEnergia EletricaMestre em Engenharia ElétricaCAPE

In-vivo diffusing-wave-spectroscopy measurements of the ocular fundus

We present what is to our knowledge the first observation of a diffusing-wave-spectroscopy signal recorded in-vivo on the ocular fundus. A modified ophthalmic microscope was developed which can acquire diffusing-wave-spectroscopy signal from the eye fundus. The diffusing-wave-spectroscopy signal was recorded in-vivo on a rabbit eye during transpupillary thermotherapy. Experimental results show the ability of the system to detect motion of the scattering sites in the ocular fundus layers during laser thermal heating. (c) 2007 Optical Society of America

Long-distance transport of L-ascorbic acid in potato

BACKGROUND: Following on from recent advances in plant AsA biosynthesis there is increasing interest in elucidating the factors contributing to the L-ascorbic acid (AsA) content of edible crops. One main objective is to establish whether in sink organs such as fruits and tubers, AsA is synthesised in situ from imported photoassimilates or synthesised in source tissues and translocated via the phloem. In the current work we test the hypothesis that long-distance transport is involved in AsA accumulation within the potato tuber, the most significant source of AsA in the European diet. RESULTS: Using the EDTA exudation technique we confirm the presence of AsA in the phloem of potato plants and demonstrate a correlation between changes in the AsA content of source leaves and that of phloem exudates. Comparison of carboxyflourescein and AgNO(3 )staining is suggestive of symplastic unloading of AsA in developing tubers. This hypothesis was further supported by the changes in AsA distribution during tuber development which closely resembled those of imported photoassimilates. Manipulation of leaf AsA content by supply of precursors to source leaves resulted in increased AsA content of developing tubers. CONCLUSION: Our data provide strong support to the hypothesis that long-distance transport of AsA occurs in potato. We also show that phloem AsA content and AsA accumulation in sink organs can be directly increased via manipulation of AsA content in the foliage. We are now attempting to establish the quantitative contribution of imported AsA to overall AsA accumulation in developing potato tubers via transgenic approaches

PV reconfiguration systems: A technical and economic study

Dynamical electrical array reconfiguration strategies for grid-connected PV systems have been proposed as solution to improve energy production due to the mismatch effect of PV plants during partial shading conditions. Strategies are based on the use of dynamic connections between PV panels given by the employment of switches that allow for each panel the series, parallel or exclusion connections, physically changing the electrical connections between the related PV modules, consequentially modifying the layout of the plant. Usually the cost of the dynamic matrix is not taken into account. This novel work evaluates the economic advantages obtained by the use of reconfiguration strategies in PV systems, by taking into consideration the price of energy due to incentives in different European and non-European countries and correlates it with the employment of two types of reconfigurators, with different internal structures. For each of the incentives proposed by the different Countries, the main strength and weakness points of the possible investment are highlighted and critically analyzed. From this analysis, it can be stated that the adoption of reconfiguration systems, in certain cases, can be a very convenient solution

Exploring Transfer Learning for Ventricular Tachycardia Electrophysiology Studies

Arrhythmogenic sites in post-ischemic ventricular tachycardia (VT) are usually identified by looking for abnormal ventricular potentials (AVPs) in intracardiac electrograms (EGMs). Unfortunately, the accurate recognition of AVPs is a challenging problem for different reasons, including the intrinsic variability in the A VP waveform. Given the high performance of deep neural networks in several scenarios, in this work, we explored the use of transfer learning (TL) for AVPs detection in intracardiac electrophysiology. A balanced set of 1504 bipolar intracardiac EGMs was collected from nine post-ischemic VT patients. The time-frequency representation was generated for each EGM by computing the synchrosqueezed wavelet transform to be used in the re-training of the convolutional neural network. The proposed approach allows obtaining high recognition results, above 90% for all the investigated performance indexes, demonstrating the effectiveness of deep learning in the recognition of AVPs in post-ischemic VT EGMs and paving the way for its use in supporting clinicians in targeting arrhythmogenic sites. In addition, this study further confirms the efficacy of the TL approach even in case of limited dataset sizes

Arrhythmogenic sites identification in post-ischemic ventricular tachycardia electrophysiological studies by explainable deep learning

Background and objective: Abnormal ventricular potentials (AVPs) in intracardiac electrograms (EGMs) are frequently considered as markers of arrhythmogenic sites in post-ischemic ventricular tachycardia (VT) during electroanatomic mapping (EAM) procedures. Their detection is strongly operator-dependent and time-consuming. This work explores the adoption of explainable deep learning to support the discrimination between physiological EGMs and AVPs. Methods: Three convolutional neural networks were trained to discriminate the target signals based on their time–frequency representations by synchrosqueezed wavelet transform. The efficacy of the method was assessed on 2561 real bipolar EGMs collected from nine post-ischemic VT patients. Results: The proposed approach achieved high performance, with accuracy levels reaching up to 89%. It also demonstrated coherent localization of the arrhythmogenic sites with respect to conventional voltage and local activation time maps. Moreover, by using saliency maps, AVPs discriminant signatures were highlighted at high frequencies (i.e., in the 103–125 Hz band, which was generally relevant for every network), in line with prior evidence. Conclusion: For the first time, deep learning has been successfully applied and robustly evaluated in the field. The proposed approach paves the way to the development of effective AI-driven systems. These systems will enable a faster, trustworthy and operator-independent identification of AVPs in VT EAM procedures. Furthermore, even without injecting prior knowledge in the adopted models, the analysis of saliency maps revealed that CNNs are prone to autonomously select time–frequency ranges of the EGMs in agreement with the current knowledge