High-fidelity transmission of entanglement over a high-loss freespace channel

Quantum entanglement enables tasks not possible in classical physics. Many quantum communication protocols require the distribution of entangled states between distant parties. Here we experimentally demonstrate the successful transmission of an entangled photon pair over a 144 km free-space link. The received entangled states have excellent, noise-limited fidelity, even though they are exposed to extreme attenuation dominated by turbulent atmospheric effects. The total channel loss of 64 dB corresponds to the estimated attenuation regime for a two-photon satellite quantum communication scenario. We confirm that the received two-photon states are still highly entangled by violating the CHSH inequality by more than 5 standard deviations. From a fundamental point of view, our results show that the photons are virtually not subject to decoherence during their 0.5 ms long flight through air, which is encouraging for future world-wide quantum communication scenarios.Comment: 5 pages, 3 figures, replaced paper with published version, added journal referenc

Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

Effect of the relative shift between the electron density and temperature pedestal position on the pedestal stability in JET-ILW and comparison with JET-C

The electron temperature and density pedestals tend to vary in their relative radial positions, as observed in DIII-D (Beurskens et al 2011 Phys. Plasmas 18 056120) and ASDEX Upgrade (Dunne et al 2017 Plasma Phys. Control. Fusion 59 14017). This so-called relative shift has an impact on the pedestal magnetohydrodynamic (MHD) stability and hence on the pedestal height (Osborne et al 2015 Nucl. Fusion 55 063018). The present work studies the effect of the relative shift on pedestal stability of JET ITER-like wall (JET-ILW) baseline low triangularity (\u3b4) unseeded plasmas, and similar JET-C discharges. As shown in this paper, the increase of the pedestal relative shift is correlated with the reduction of the normalized pressure gradient, therefore playing a strong role in pedestal stability. Furthermore, JET-ILW tends to have a larger relative shift compared to JET carbon wall (JET-C), suggesting a possible role of the plasma facing materials in affecting the density profile location. Experimental results are then compared with stability analysis performed in terms of the peeling-ballooning model and with pedestal predictive model EUROPED (Saarelma et al 2017 Plasma Phys. Control. Fusion). Stability analysis is consistent with the experimental findings, showing an improvement of the pedestal stability, when the relative shift is reduced. This has been ascribed mainly to the increase of the edge bootstrap current, and to minor effects related to the increase of the pedestal pressure gradient and narrowing of the pedestal pressure width. Pedestal predictive model EUROPED shows a qualitative agreement with experiment, especially for low values of the relative shift

A rational decentralized generalized Nash equilibrium seeking for energy markets

We propose a method to design a decentralized energy market which guarantees individual rationality (IR) in expectation, in the presence of system-level grid constraints. We formulate the market as a welfare maximization problem subject to IR constraints, and we make use of Lagrangian duality to model the problem as a n-person non-cooperative game with a unique generalized Nash equilibrium (GNE). We provide a distributed algorithm which converges to the GNE. The convergence and properties of the algorithm are investigated by means of numerical simulations

Gravity Data Allow to Image the Shallow‐Medium Subsurface Below Mud Volcanoes

The debate about the conceptual model of mud volcanoes functioning is still alive in the literature. A large part of the literature focuses on the characterization of the deep reservoir where expelled fluids are expected to originate. Another part of literature is focused on the study of the shallow system of mud volcanoes, which could influence the short‐term variations in mud volcanoes activity. We present and analyze a new data set of micro‐gravimetric data to study the area of the Nirano Salse , Italy. Unlike what is commonly assumed for the study area, our results suggest that the geomorphology of the Nirano Salse is not related to a caldera collapse above a shallow mud chamber, but to the surface expression of slip distribution of a fault termination along which the fluids ascended to the surface. We believe that gravimetric data can significantly improve the study of hydrocarbon seeps and mud volcanism.</p

Apícula: Static Detection of API Calls in Generic Streams of Bytes

API functions often require the crafting of specific inputs and may return some output that is usually processed by the code that immediately follows their invocation. In this work, we claim that - for some APIs - those two stages are both frequently similar across different binaries and sufficiently unique to be fingerprinted. We build upon this intuition and present Apìcula, a static analysis tool for identifying API calls in generic streams of bytes, such as memory dumps, network traffic, or object code files. In a nutshell, Apìcula leverages the control flow graph of a binary to generate a set of fingerprints for all basic blocks that end with a call instruction. Those sets are then compared against a database of pre-computed fingerprints to establish whether any known API is being invoked. Due to its applicability to unstructured byte streams, Apìcula can complement the reverse engineering process when this is carried out over memory dumps collected after a cyber-incident. Moreover, it can enable behavioral analysis in a fully static way, by identifying sequences of API calls even in non executable binaries. We provide a series of experiments that are instrumental (1) in demonstrating that the same fingerprints computed for specific APIs can be observed across different binaries and (2) in iden- tifying a subset of the Windows APIs whose usage can be detected by Apìcula with sufficient precision and sensitivity, focusing in particular on malicious binaries. Furthermore, we illustrate two techniques that can be used to validate different fingerprint databases in case someone wants to detect APIs belonging to libraries different from those that we consider in this work. In particular, we prove that fingerprints associated with different APIs are remarkably dissimilar and therefore can be employed for distinguishing between APIs. More specifically, we find that fingerprint sets associated with different APIs present on average a Jaccard index value of 0.000125; in comparison, the average similarity between fingerprint sets associated with the same API is 0.29 (Jaccard index) for binaries compiled with the same optimization level and 0.07 (Jaccard index) for binaries compiled with different optimization levels. Moreover, we show that we can build databases of fingerprints that are sufficiently comprehensive to identify specific APIs in unseen binaries. More precisely, we identify 228 different APIs among the Windows APIs (including the C run-time libraries) whose usage can be detected by Apìcula with sensitivity greater than 80% and a false discovery rate lower than 5%

The ”Salse di Nirano” mud volcanoes: hints from gravity data

Mud volcanoes are distributed throughout the globe, both on- and offshore. Mud volcanism has been widely investigated from the geological, geophysical, and geochemical points of view. The study of mud volcanoes has important implications in energy resource exploration, geohazard identification, and greenhouse gas emissions assessment (mainly CH4 and CO2). Mud volcano eruptions are mainly driven by a gravitative instabilities and fluid overpressure, due to the overall low density of clay/water/gas mixtures with respect to surrounding units. The geohazard of mud volcanoes is to date underrated despite the violent eruptive examples occurred in the past. For instance, the eruption of the Piparo mud volcano (1997, island of Trinidad) damaged electrical and water infrastructures and killed animals and livestock. In 2014, the eruption of the Macalube di Aragona (Italy) mud volcano killed two children. The understanding of the mechanisms regulating mud volcanoes is, therefore, important also in terms of hazard evaluation. To date, a physical conceptual model of the Nirano Salse, Italy, ascribes the eruptions to the presence of over-pressurized fluids that are expelled from a main deep reservoir. The latter is put into communication with the surface due to the episodically reactivation of pre-existing faults or pipes. The debate about this conceptual model is still open. To improve our current understanding, a new high-resolution dataset of gravimetric data was acquired. Our goal is to provide an insight about the subsurface structure of the investigated domain. The gravimetric inversion aims to identify the structural setting of Nirano and the presence of gas traps and faults. The gravity inversion results indicate the existence of a low-density zone (1200-1500 m long, 100-200 m wide, 800 m deep) with an almost planar shape aligned along a NW-SE structural trend, typical of the Northern Apennines chain. This zone likely represents the intrusion of mud/gas in the damage zone of a sub-vertical fault, which feeds shallow fluid reservoirs