Pressure stimulated currents in rocks and their correlation with mechanical properties

The spontaneous electrification of marble samples was studied while they were subjected to uniaxial stress. The Pressure Stimulated Current (PSC) technique was applied to measure the charge released from compressed Dionysos marble samples, while they were subjected to cyclic loading. The experimental results demonstrate that, in the linear elastic region of the sample, no PSC is recorded, while beyond the stress limit (s>0.60), observable variations appear, which increase considerably in the vicinity of sample failure, reaching a maximum value just before the failure. The emitted current is reduced on each loading cycle and it has a reciprocal dependence to the normalized Young modulus. The MCD model, applied out of the vicinity of sample failure explains successfully the above findings. The existence of a "memory-like" behavior of the sample, could justify the weakness or absence of electrical earthquake precursors, during an aftershock sequence

Representing Time-dependent Information in Multidimensional XML

Multidimensional XML (MXML) is an extension of XML that incorporates dimensions in order to represent in an elegant and concise way context-dependent data, that is, data which can exhibit different variations in value or structure (e.g. that can exist in different languages or various degrees of detail). In this paper we show that MXML dimensions can be used to express time and associate it with XML elements and attributes. We discuss the properties of time domain and the features of MXML which are necessary in order to represent time, and give key points that motivate further investigation on the use of MXML for representing time-dependent data

A Case of Invasive Sinonasal Carcinosarcoma: The Importance of Early Detection

Sinonasal carcinosarcomas represent rare neoplasms, with aggressive character and unfavourable prognosis. We present a case of extensive sinonasal carcinosarcoma extending into the anterior cranial fossa and into the orbit and also a review of the current international literature regarding this rare yet aggressive neoplasm. There is currently a lack of specific guidelines on the optimal management of sinonasal carcinosarcoma and the treatment represents a challenge for the clinician. The key message that we would like to disseminate to our colleagues is the importance of suspicion and early detection, as well as the necessity to adopt a holistic approach when counselling patients

Fabrication of Nanostructured GaAs/AlGaAs Waveguide for Low-Density Polariton Condensation from a Bound State in the Continuum

Exciton-polaritons are hybrid light-matter states that arise from strong coupling between an exciton resonance and a photonic cavity mode. As bosonic excitations, they can undergo a phase transition to a condensed state that can emit coherent light without a population inversion. This aspect makes them good candidates for thresholdless lasers, yet short exciton-polariton lifetime has made it difficult to achieve condensation at very low power densities. In this sense, long-lived symmetry-protected states are excellent candidates to overcome the limitations that arise from the finite mirror reflectivity of monolithic microcavities. In this work we use a photonic symmetry protected bound state in the continuum coupled to an excitonic resonance to achieve state-of-the-art polariton condensation threshold in GaAs/AlGaAs waveguide. Most important, we show the influence of fabrication control and how surface passivation via atomic layer deposition provides a way to reduce exciton quenching at the grating sidewalls

A strategy to incorporate prior knowledge into correlation network cutoff selection

Correlation networks are frequently used to statistically extract biological interactions between omics markers. Network edge selection is typically based on the statistical significance of the correlation coefficients. This procedure, however, is not guaranteed to capture biological mechanisms. We here propose an alternative approach for network reconstruction: a cutoff selection algorithm that maximizes the overlap of the inferred network with available prior knowledge. We first evaluate the approach on IgG glycomics data, for which the biochemical pathway is known and well-characterized. Importantly, even in the case of incomplete or incorrect prior knowledge, the optimal network is close to the true optimum. We then demonstrate the generalizability of the approach with applications to untargeted metabolomics and transcriptomics data. For the transcriptomics case, we demonstrate that the optimized network is superior to statistical networks in systematically retrieving interactions that were not included in the biological reference used for optimization

Non-extensive statistical analysis of acoustic emissions series recorded during the uniaxial compression of brittle rocks

Non-extensive statistical physics (NESP) provides the theoretical tool to investigate complex systems that appear in different length-scales and violate the classical Boltzmann–Gibbs statistics. In the present study, we apply the concept of NESP to analyze the Acoustic Emissions (AE) series recorded during uniaxial compression of brittle rocks, such as marble and sandstone specimens. In both types of rock samples, the cumulative distribution of inter-event times (interval times between successive AE hits) are well described by the q-exponential function. The variations of the q-index of Tsallis entropy and of the βq parameter with the applied stress follow distinct behavior in each type of rock, indicating in both cases the entrance of the system to the critical stage of fracture. The analysis of the experimental data suggests that NESP is suitable for describing AE activity in rock samples under compression, in a similar way to Earth's seismic activity. © 201

Evaluation of the choriocapillaris after photodynamic therapy for chronic central serous chorioretinopathy. A review of optical coherence tomography angiography (OCT-A) studies

Purpose: Emerging evidence suggests that choroidal microcirculation and microstructural changes after verteporfin photodynamic therapy (vPDT) for chronic central serous chorioretinopathy (CSC) can be shown in detail using OCT-Angiography (OCT-A). The use of OCT-A for the examination of choriocapillaris (CC) has attracted significant attention as the technique offers potential explanations for the effects of vPDT on choroidal tissue. Methods: A meticulous literature search was performed in the PubMed database without restriction on year of publication until June 2021. The reference list of all electronically retrieved articles was carefully reviewed for potentially relevant articles that had not been identified. Results: We identified and reviewed 11 studies reporting a comprehensive update on microvasculature and morphologic changes of the CC layer as seen on OCT-A in chronic CSC. The reviewed articles extensively analyze both the qualitative and quantitative characteristics of the CC flow pattern after applying vPDT safety-enhanced protocols. The changes in the CC plexus indicate the potential of beneficial or deleterious treatment effect on choroidal tissue remodeling. The reviewed series have revealed variability of flow pattern, vessel density, and perfusion of the CC over time. Conclusion: The CC plexus alterations during the post-vPDT period in chronic CSC may imply the treatment effect on choroidal tissue, indicating the potential of anatomical or functional recovery over time. The reviewed literature may confirm the diagnostic value of OCT-A in the assessment of the pathophysiology of eyes with CSC. [Figure not available: see fulltext.] © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature