Reactive oxygen species and transcript analysis upon excess light treatment in wild-type Arabidopsis thaliana vs a photosensitive mutant lacking zeaxanthin and lutein

<p>Abstract</p> <p>Background</p> <p>Reactive oxygen species (ROS) are unavoidable by-products of oxygenic photosynthesis, causing progressive oxidative damage and ultimately cell death. Despite their destructive activity they are also signalling molecules, priming the acclimatory response to stress stimuli.</p> <p>Results</p> <p>To investigate this role further, we exposed wild type <it>Arabidopsis thaliana </it>plants and the double mutant <it>npq1lut2 </it>to excess light. The mutant does not produce the xanthophylls lutein and zeaxanthin, whose key roles include ROS scavenging and prevention of ROS synthesis. Biochemical analysis revealed that singlet oxygen (¹O₂) accumulated to higher levels in the mutant while other ROS were unaffected, allowing to define the transcriptomic signature of the acclimatory response mediated by ¹O₂which is enhanced by the lack of these xanthophylls species. The group of genes differentially regulated in <it>npq1lut2 </it>is enriched in sequences encoding chloroplast proteins involved in cell protection against the damaging effect of ROS. Among the early fine-tuned components, are proteins involved in tetrapyrrole biosynthesis, chlorophyll catabolism, protein import, folding and turnover, synthesis and membrane insertion of photosynthetic subunits. Up to now, the <it>flu </it>mutant was the only biological system adopted to define the regulation of gene expression by ¹O₂. In this work, we propose the use of mutants accumulating ¹O₂by mechanisms different from those activated in <it>flu </it>to better identify ROS signalling.</p> <p>Conclusions</p> <p>We propose that the lack of zeaxanthin and lutein leads to ¹O₂accumulation and this represents a signalling pathway in the early stages of stress acclimation, beside the response to ADP/ATP ratio and to the redox state of both plastoquinone pool. Chloroplasts respond to ¹O₂accumulation by undergoing a significant change in composition and function towards a fast acclimatory response. The physiological implications of this signalling specificity are discussed.</p

A Federated Learning Framework for Stenosis Detection

This study explores the use of Federated Learning (FL) for stenosis detection in coronary angiography images (CA). Two heterogeneous datasets from two institutions were considered: Dataset 1 includes 1219 images from 200 patients, which we acquired at the Ospedale Riuniti of Ancona (Italy); Dataset 2 includes 7492 sequential images from 90 patients from a previous study available in the literature. Stenosis detection was performed by using a Faster R-CNN model. In our FL framework, only the weights of the model backbone were shared among the two client institutions, using Federated Averaging (FedAvg) for weight aggregation. We assessed the performance of stenosis detection using Precision (P rec), Recall (Rec), and F1 score (F1). Our results showed that the FL framework does not substantially affects clients 2 performance, which already achieved good performance with local training; for client 1, instead, FL framework increases the performance with respect to local model of +3.76%, +17.21% and +10.80%, respectively, reaching P rec = 73.56, Rec = 67.01 and F1 = 70.13. With such results, we showed that FL may enable multicentric studies relevant to automatic stenosis detection in CA by addressing data heterogeneity from various institutions, while preserving patient privacy

A calibration-verification testbed for electrical energy meters under low power quality conditions

open7A calibration/verification testbed for electrical energy meters is under development at the Istituto Nazionale di Ricerca Metrologica, the National Metrology Institute of Italy. The testbed will be employed for the calibration of commercial static power energy meters under low power conditions and for simulating the verification in the field of energy meters under real operational conditions. The activity is in collaboration with the Ministry for Economic Development and aims to the future development of regulatory documents for energy metering verification.openCallegaro, Luca; Aprile, Giulia; Cultrera, Alessandro; Galliana, Flavio; Germito, Gabriele; Serazio, Danilo; Trinchera, BrunoCallegaro, Luca; Aprile, Giulia; Cultrera, Alessandro; Galliana, Flavio; Germito, Gabriele; Serazio, Danilo; Trinchera, Brun

Laboratory reproduction of on-field low power quality conditions for the calibration/verification of electrical energy meters

– In this work we present a method for testing static active energy meters in low power quality conditions recorded at installation sites. Voltage and current waveforms recorded on the field with a calibrated portable instrument were reproduced with an accurate phantom power generator up to the 40th harmonic. The error on the active energy measurement of an energy meter under test (WDUT) in conditions reproduced from the on-field measurements was evaluated in comparison with a reference meter (WREF). On-field data were recorded at a 50 kW self production photovoltaic facility. This method allows the laboratory reproduction of realistic (distorted) on-field conditions in a metrologically traceable framewor

High-dose clopidogrel, prasugrel or ticagrelor: trying to unravel a skein into a ball

Antiplatelet therapy is a mainstay in the management of coronary artery disease. Indeed, optimal and rapid inhibition of platelet function is a key therapeutic goal in patients with acute coronary syndromes and those undergoing percutaneous coronary intervention. Currently, dual antiplatelet treatment with aspirin and clopidogrel is the gold standard care in patients with acute coronary syndromes or receiving coronary stents without prohibitive bleeding risk. However, recent data show that the efficacy of clopidogrel is hampered by its slow and variable platelet inhibition, with ensuing increased risk of ischemic events, including death, myocardial infarction and stent thrombosis. Novel agents such as prasugrel and ticagrelor have been developed to clopidogrel limits and thus improve cardiovascular outcomes. This article presents a comprehensive overview of the benefits and limitations of current and shortly available antiplatelet agents, providing detailed arguments in favor and against prasugrel and ticagrelor

Material radiopurity control in the XENONnT experiment

The selection of low-radioactive construction materials is of the utmost importance for rare-event searches and thus critical to the XENONnT experiment. Results of an extensive radioassay program are reported, in which material samples have been screened with gamma-ray spectroscopy, mass spectrometry, and $^{222}Rn$ emanation measurements. Furthermore, the cleanliness procedures applied to remove or mitigate surface contamination of detector materials are described. Screening results, used as inputs for a XENONnT Monte Carlo simulation, predict a reduction of materials background (∼17%) with respect to its predecessor XENON1T. Through radon emanation measurements, the expected $^{222}Rn$ activity concentration in XENONnT is determined to be 4.2 $(^{+0.5}_{−0.7}) μBq/kg$, a factor three lower with respect to XENON1T. This radon concentration will be further suppressed by means of the novel radon distillation system

Cosmology and Astrophysics of Minimal Dark Matter

We consider DM that only couples to SM gauge bosons and fills one gauge multiplet, e.g. a fermion 5-plet (which is automatically stable), or a wino-like 3-plet. We revisit the computation of the cosmological relic abundance including non-perturbative corrections. The predicted mass of e.g. the 5-plet increases from 4.4 TeV to 10 TeV, and indirect detection rates are enhanced by 2 orders of magnitude. Next, we show that due to the quasi-degeneracy among neutral and charged components of the DM multiplet, a significant fraction of DM with energy E > 10^17 eV (possibly present among ultra-high energy cosmic rays) can cross the Earth exiting in the charged state and may in principle be detected in neutrino telescopes.Comment: 24 pages, 10 figures; v2: typos corrected, to appear on NP

Pleural Effusion Secondary to Multiple Myeloma: Is Daratumumab an Effective Treatment? A Case Report

Extramedullary (EM) plasmacytoma disease is an aggressive presentation at diagnosis and relapse for multiple myeloma (MM) patients. EM plasmacytoma is divided into two groups: the first group comprises tumors that extend directly from osteolytic bone lesions, while the second results from plasmacytoma infiltration into soft tissues, with no relation to the bone. Despite new therapies and monoclonal antibodies, the survival for patients with EM plasmacytoma is poor. The involvement of pleural effusion is uncommon in multiple myeloma