The Governor, the Bishop, and the Patricians: The Contest for the Cathedral Square in Spanish Milan (1535-1706)

In the 16th and 17th centuries, the ambitious reorganization of the urban fabric sponsored and supervised by princes or ruling elites, usually aimed at establishing the power and prestige of the central authority, transformed most Italian cities. However, the separation within the city center between a political and ceremonial space, usually centered around the palace of the prince, and a marketplace, that came to characterize most urban contexts, did not occur in Milan. In order to preserve peace and stability in a period of intense warfare, the monarchy sacrificed an invasive oversight of the city and abdicated a higher degree of local power, choosing instead to delegate it to the urban patriciate, the merchant elites, and the Ambrosian church. Free of any restriction, and in order to preserve their financial interests and emphasize their political prominence, the families of the urban elites maintained the economic function of the area around the cathedral square at the expense of the royal-ducal palace and articulated an alternative power network anchored to their palaces in the residential neighborhoods outside the city center

Fermionic correlations as metric distances : a useful tool for materials science

We introduce a rigorous, physically appealing, and practical way to measure distances between exchange-only correlations of interacting many-electron systems, which works regardless of their size and inhomogeneity. We show that this distance captures fundamental physical features such as the periodicity of atomic elements, and that it can be used to effectively and efficiently analyze the performance of density functional approximations. We suggest that this metric can find useful applications in high-throughput materials design.Comment: 5 pages, 4 figure

A physics-informed generative model for passive radio-frequency sensing

Electromagnetic (EM) body models predict the impact of human presence and motions on the Radio-Frequency (RF) stray radiation received by wireless devices nearby. These wireless devices may be co-located members of a Wireless Local Area Network (WLAN) or even cellular devices connected with a Wide Area Network (WAN). Despite their accuracy, EM models are time-consuming methods which prevent their adoption in strict real-time computational imaging problems and Bayesian estimation, such as passive localization, RF tomography, and holography. Physics-informed Generative Neural Network (GNN) models have recently attracted a lot of attention thanks to their potential to reproduce a process by incorporating relevant physical laws and constraints. Thus, GNNs can be used to simulate/reconstruct missing samples, or learn physics-informed data distributions. The paper discusses a Variational Auto-Encoder (VAE) technique and its adaptations to incorporate a relevant EM body diffraction method with applications to passive RF sensing and localization/tracking. The proposed EM-informed generative model is verified against classical diffraction-based EM body tools and validated on real RF measurements. Applications are also introduced and discussed

Enhancing Lightpath QoT Computation with Machine Learning in Partially Disaggregated Optical Networks

Increasing traffic demands are causing network operators to adopt disaggregated and open networking solutions to better exploit optical transmission capacity, and consequently enable a software-defined networking (SDN) approach to control and management that encompasses the WDM data transport layer. In these frameworks, a quality of transmission estimator (QoT-E) that gives the generalized signal-to-noise ratio (GSNR) is commonly used to compute the feasibility of transparent lightpaths (LP)s, taking into account the amplified spontaneous emission (ASE) noise and the nonlinear interference (NLI). In general, the ASE noise is the main contributor to the GSNR and is also the most challenging noise component to evaluate in a scenario with varying spectral loads, due to fluctuations in the optical amplifier responses. In this work, we propose a machine learning (ML) algorithm that is trained using different ASE-shaped spectral loads in order to predict the OSNR component of the GSNR; this methodology is subsequently used in combination with a QoT-E in the lightpath computation engine (L-PCE). We present an experiment on a point-to-point optical line system (OLS), including 9 commercial erbium-doped fiber amplifiers (EDFA)s used as black-boxes, each with variable gain and tilt values, and 8 fibers that are characterized by distinct physical parameters. Within this experiment, we receive the signal at the end of the OLS, measuring the bit-error-rate (BER) and the power spectrum, over 2520 different spectral loads. From this dataset, we extract the expected GSNRs and their linear and nonlinear components. Through joint application of a ML algorithm and the open-source GNPy library, we obtain a complete QoT-E, demonstrating that a reliable and accurate LP feasibility predictor may be implemented

Gain profile characterization and modelling for an accurate EDFA abstraction and control

Relying on a two-measurement characterization phase, a gain profile model for dual-stage EDFAs is presented and validated in full spectral load condition. It precisely reproduces the EDFA dynamics varying the target gain and tilts parameters as shown experimentally on two commercial items from different vendors

Transistors based on the Guanosine molecule (a DNA base)

Abstract Molecules are attractive to develop nano-electronic devices. In this paper a new type of transistor is realized by using self-organized films of the Guanosine molecule, a modified DNA base. With its 40 nm channel length the transistor is a good starting point for a new class of nano-electronics devices. Experimental current-voltage characteristics are shown. A circuital model is also proposed

Introduction to the special issue of the Consortium of Organizations for Strong Motion Observation Systems (COSMOS) international guidelines for applying noninvasive geophysical techniques to characterize seismic site conditions

Knowledge about local seismic site conditions provides critical information to account for site effects that are commonly observed in strong motion recordings. Certainly, other wave propagation effects can influence these observations, which are attributable to variations in material properties of the paths traveled by the waves, as well as the characteristics of the seismic source. However, local geologic conditions, particularly, when under shear-wave excitation, are known to have a strong influence on the behavior of ground shaking in the frequency range that is expected to directly affect the built environment. Thus, shear waves traveling in the shallow subsurface—defined here as tens to hundreds of meters beneath the ground surface—are the main foci for application and research in the earthquake engineering community. To assess the potential for important site effects, a number of approaches collectively known as site response analyses (SRA) are constantly developed. They are also continuously tested and refined with the aim to reduce the uncertainties associated with each technique. Although SRA can be carried out empirically, a set of popular procedures within the suite of SRA methods relies on numerical techniques (one dimensional [1D] transfer functions) and is further differentiated by earthquake engineers as ground response analysis (GRA). Fundamentally, GRAs require input from measurements through in situ seismic recordings that are generally known as the field data acquisition component of site characterization. Following such acquisitions are the associated data processing and analysis phases that produce the shear-wave velocity (VS) profile as the main output, as well as its derivative, the time-averaged VS of the upper 30 m from the surface (VS30), which is the main site index term in ground motion modeling (Boore et al. 1993; Borcherdt 1994). To advance knowledge about site effects phenomena, special SRA-focused sessions have become common occurrences at internationally held earthquake conferences and scientific journals have frequently devoted special issues (or sections) to document the state of the knowledge (Field et al. 2000; Panzera et al. 2017; Kaklamanos et al. 2021). Recently, Kaklamanos et al. (2021) introduced a collection of papers compiled as a special section entitled Advancements in Site Response Estimation, which originated from a similarly named special session planned for the 2020 Annual Meeting of the Seismological Society of America (which was canceled due to the COVID-19 pandemic). Through open submissions, the guest editors organized articles into five interrelated sections about various aspects of site response (Kaklamanos et al. 2021), including five papers addressing uncertainties as contributed through the SRA framework, as well as one general section on site characterization. Of the six papers included in this section, only two were primarily focused on VS measurements and both focused on the use of surface wave methods to generate in situ VS models (Hobiger et al. 2021; Stephenson et al. 2021). The study locations of each paper were unrelated, but both papers shared the general approach of comparing surface-wave-based analytical estimates of the site dominant frequencies (fd) to that of earthquake horizontal-to-vertical spectral ratios (eHVSR). These independent studies found strong agreement between their modeled and observed fd. In a more recent effort, S. Matsushima and others (http://www.esg6.jp/blind.html; last accessed 4 April 2022) conducted blind tests that were mainly focused on SRA through participation by international analysts as part of the 2021 6th International Symposium of the Effects of Surface Geology on Seismic Motion. During the past two decades, advancements in the field of site characterization have also benefited from activities that were similarly conducted for SRA. This period coincided with a time when applying cost-effective noninvasive surface-wave approaches gained tremendous popularity worldwide. Particularly important were related crossover efforts that attempted to assess uncertainties propagated from methodologies that apply surface-based site characterization to GRAs. To this end, a number of blind trials on-site characterization methods were conducted and most of these activities were directly followed with developments of guidelines for best practices by organizers of the trials (Cornou et al. 2007; Boore and Asten 2008; Garofalo et al. 2016; Foti et al. 2018; Asten et al. 2022, this issue). Unassociated guidelines, technical reports, and textbooks about the application of surface wave methods were also independently published by authors and many were participants of the aforementioned trials (SESAME 2004; Yong et al. 2013; Martin et al. 2014; Dal Moro 2014; Foti et al. 2015; Martin et al. 2017). Despite these accomplishments, the findings illuminated solutions, which also inherently beget more questions, and thus the continuation of these activities is expected for the foreseeable future (Askan et al. 2022)

Site effects on fault-zone : results from ambient noise measurements

It is well known that fault zones are generally characterized by a highly fractured low-velocity belt (damage zone), hundreds of meter wide, bounded by higher-velocity area (host rock) that can broaden for some kilometres (Ben-Zion et al,. 2003; Ben-Zion and Sammis, 2003, 2009 and references therein). Such geometrical setting and impedance contrast is in principle proficient to produce local amplification of ground motion (Peng and Ben-Zion, 2006; Calderoni et al., 2010; Cultrera et al., 2003; Seeber et al., 2000), as well as to support the development of fault zone trapped waves. There is a large number of papers that describe propagation properties of fault-guided waves (e.g., Li et al., 1994; Mizuno, Nishigami, 2006) in terms of ground motion amplification having a propensity to be maximum along the fault-parallel direction. These observations, both in theoretical and experimental approaches deal with almost pure strike slip faults such as the S. Andreas and the Anatolian faults (see Li et al., 2000; Ben Zion et al., 2003). Studies about local seismic response nearby fault zones have been performed in Italy and in California by Cultrera et al. (2003), Calderoni et al. (2010), Pischiutta et al. (2012) who observed evidences of ground motion amplification in the fault zone environments and strong directional effects with high angle to the fault strike. Similar studies, performed by Rigano et al. (2008) and Di Giulio et al. (2009) documented the presence of a systematic polarization of horizontal ground motion, near faults located on the eastern part of the Etnean area, that was never coincident with the strike of the tectonic structures. These directional effects were observed both during local and regional earthquakes, as well as using ambient noise measurements, therefore suggesting the use of microtremors for investigating ground motion polarization properties along and across the main tectonic structures of all the volcanic area. All the observations showed evidence of directional amplifications not parallel to the fault strike, as would have been expected for trapped waves. In the present study, the results of new measurements are shown and discussed. The data were recorded in newly investigated tectonic structures of the volcano located both on the western flank of Mt. Etna (Ragalna fault system) and on the eastern flank of the volcano (Piedimonte fault) as well as in a non-volcanic area (Malta Island), located in the Hyblean foreland. Moreover, several measurements were performed in areas significantly distant from the studied tectonic structures (Piano dei Grilli and Malta area), in order to observe how directional effects can change at increasing distance from the fault lines.peer-reviewe

Isolated hepatocytes versus hepatocyte spheroids: in vitro culture of rat hepatocytes.

The use of hepatocytes that express liver-specific functions to develop an artificial liver is promising. Unfortunately, the loss of specialized liver functions (dedifferentiation) is still a major problem. Different techniques, such as collagen entrapment, spherical multicellular aggregates (spheroids), and coculture of hepatocytes with extracellular matrix, have been used to improve the performance of hepatocytes in culture. The aim of this study was to compare two different models of hepatocyte isolation in culture: isolated hepatocytes (G1) and hepatocyte spheroids (60% hepatocytes, 40% nonparenchymal cells, and extracellular matrix) (G2). To test functional activity of hepatocytes, both synthetic and metabolic, production of albumin and benzodiazepine transformation into metabolites was tested. G2 showed a high albumin secretion, while a decrease after 15 days of culture in G1 was noted. Diazepam metabolites were higher in G2 than in G1 in all samples, but had statistical significance at days 14 and 21 (p < 0.01). The glycogen content, after 30 days of culture, was very low in G1 (14.2 ± 4.4%), while in G2 it was 72.1 ± 2.6% (p < 0.01). Our study confirms the effectiveness of a culture technique with extracellular matrix and nonparenchymal cells. Maintenance of a prolonged functional activity has been related to restoration of cell polarity and close cell-to-cell contact. We showed that isolated hepatocytes maintain their functional activity for a period significantly reduced, when compared to the hepatocyte spheroids. We confirmed the role of extracellular matrix as a crucial component to promote hepatocyte homeostasis, and the close link between cellular architecture and tissue-specific functions