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Remote sensing assessment of the weed adaptability to soil salinization induced by extreme droughts on coastal agriculture
Get PDFSalinization and drought pose significant challenges to agriculture in coastal regions, yet their combined impact on crop production and weed proliferation remains understudied. This study investigated the influence of salinity caused by extreme droughts on agricultural ecosystems in the Po River Delta (Italy), using remote sensing techniques and soil measurement, focusing on crop health and weed resilience. Our findings reveal that prolonged drought conditions are exacerbated by saline water intrusion and elevated soil salinity levels, particularly in fields closer to the coast. While crops, notably soybeans, exhibited susceptibility to salinity stress, weeds displayed remarkable resilience, thriving in adverse conditions and outcompeting crops. Notably, weed populations showed increased density and adaptability, even in areas of high salinity and drought. These findings underscore the urgent need for comprehensive strategies to mitigate the impact of salinity and drought on crop productivity and manage weed infestations in coastal agricultural areas
Neuroinflammation in Radiation Maculopathy: A Pathophysiologic and Imaging Perspective
Get PDFBackground: Radiation maculopathy (RM) is a delayed, sight-threatening complication of ocular radiotherapy. Traditionally regarded as a pure microvascular disease, emerging evidence points to the central role played by retinal neuroinflammation, driven by microglial activation and cytokine dysregulation affecting both the retina and the choroid. Hyperreflective retinal foci, neuroinflammatory in origin (I-HRF), visualized through advanced imaging modalities such as spectral domain optical coherence tomography (OCT), have been identified as early and critical biomarkers of both preclinical and clinical retinal neuroinflammation. Materials and Methods: This review synthesizes findings from experimental and clinical studies to explore the pathophysiology of neuroinflammation and the associated imaging parameters in RM. Results: The integration of experimental and clinical evidence specifically underscores the significance of I-HRF as an early indicator of neuroinflammation in RM. OCT enables the identification and quantification of these biomarkers, which are linked to microglial activation and cytokine dysregulation. Conclusions: The pathophysiology of RM has evolved from a predominantly vascular condition to one strongly secondary to neuroinflammatory mechanisms involving the retina and choroid. In particular, I-HRF, as early biomarkers, offers the potential for preclinical diagnosis and therapeutic intervention, paving the way for improved management of this sight-threatening complication
Real-Life Evaluation of the MOGAD Diagnostic Criteria
No full textBackground and objectives: Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) international panel criteria have been recently proposed to guide MOGAD diagnosis. The aim of this study was to evaluate the criteria performance and assess the discrepancies in their application in the clinical practice in an Italian multicenter cohort and to discuss some challenging aspects.
Methods: We applied the 2023 MOGAD criteria to patients who tested MOG-Abs positive on cell-based assays and were retrospectively recruited from 29 centers. Detailed clinical and paraclinical data were collected. Patients were classified as true positive/negative (TP/TN) in case of concordance between MOGAD criteria application and enrolling center final diagnosis, as false positive (FP) when MOGAD criteria were fulfilled but final diagnosis was different from MOGAD, and as false negative (FN) when MOGAD criteria were not fulfilled and final diagnosis of MOGAD was confirmed. Central revision of FN and FP cases was performed.
Results: We included 214 patients (median age at onset 38.2 years [interquartile range 25.2-50.7], 60.3% female, 23 pediatric patients). Of these, 168 (78.5%) were classified as TP, 9 (4.2%) as FP, 23 (10.7%) as FN, and 14 (6.5%) as TN. The sensitivity of MOGAD criteria was 87.96% (CI 82.5%-92.2%), specificity 60.9% (CI 38.5%-80.3%), positive predictive value 94.9% (CI 91.8%-96.9%), negative predictive value 37.8% (CI 26.7%-50.2%), and accuracy 85.1% (CI 79.6%-89.5%). In 11 of 32 revised cases, available information did not allow a proper diagnosis. Independent revision changed the diagnosis in 17 of 21 remaining cases, increasing the performance of the MOGAD criteria. Of note, in 3 cases, diagnostic criteria were satisfied only at follow-up. The sensitivity and specificity after independent revision were 98.9% (CI 96%-99.9%) and 91.7% (CI 73%-98.9%), respectively. Moreover, 29 of 214 patients (13.6%) had 1 or more asymptomatic radiologic supportive features, and in 50% (3/6) of FP cases, independent revision did not confirm the presence of supportive features. Patients with clear positive serum titer or CSF-only MOG-Abs were those who received more commonly a MOGAD diagnosis.
Discussion: MOGAD criteria demonstrate a good performance across different centers; however, controversial cases might benefit from collegial discussion and reassessment of MOGAD criteria during the follow-up. Main challenges include availability of proper radiologic data and interpretation of radiologic supportive features
Inflation without an inflaton
No full textWe propose a novel scenario in which scalar perturbations, which seed the large-scale structure of the universe, are generated without relying on a scalar field (the inflaton). In this framework, inflation is driven by a de Sitter space time, where tensor metric fluctuations (i.e., gravitational waves) naturally arise from quantum vacuum oscillations, and scalar fluctuations are generated via second-order tensor effects. We compute the power spectrum of such scalar fluctuations and show it to be consistent with near scale invariance. We derive the necessary conditions under which scalar perturbations become significant and much larger than the tensor modes, and we identify a natural mechanism to end inflation via a transition to a radiation-dominated phase. Our proposed mechanism could remove the need for a model-dependent scenario: the choice of a scalar field, as the inflaton, to drive inflation
Outcome and Disease Progression in NYHA Functional Class I and II Patients With Wild-Type Transthyretin Cardiomyopathy Treated With Tafamidis
Get PDFSystematic Review and Expert Consensus on the Use of Long-acting Monoclonal Antibodies for Prevention of Respiratory Syncytial Virus Disease: ARMADA (Advancing RSV Management And Disease Awareness) Taskforce
No full textBackground Long-acting monoclonal antibodies (LAmAbs) could dramatically reduce the respiratory syncytial virus (RSV) disease burden in children if implemented using clear, evidence-based recommendations. Methods The ARMADA Taskforce - an international, multidisciplinary expert panel - undertook a systematic review to develop LAmAbs consensus recommendations for RSV disease prevention in children. Results The Taskforce recommends LAmAbs for all infants aged <8 months in the absence of maternal RSV vaccination, preterm infants (<37 weeks' gestational age) aged <12 months, and children <24 months with high-risk conditions. Seasonal LAmAb administration is recommended, although in RSV-endemic countries decisions should be made locally concerning administration year-round or with peak RSV incidences. Conclusions The Taskforce strongly endorses LAmAbs implementation based on their efficacy, effectiveness, and public health impact. These recommendations provide a blueprint to inform guidelines worldwide. Wider equitable access to LAmAbs at affordable prices, especially in low- and middle-income countries is needed to reduce the childhood RSV burden
Exploring Low-GWP Alternatives for Heat Pumps: A Drop-in Comparative Study of R1234yf/R600a and R134a
No full textThe progressive phase-out of high-GWP refrigerants as mandated by the Kigali Amendment to the Montreal Protocol and the EU F-gas Regulation necessitates the exploration of sustainable alternatives within the HVAC&R industry. A recent proposal by the Council and the European Parliament aims to significantly reduce Hydrofluorocarbons (HFCs) consumption by 2050, including specific bans on high-GWP fluorinated gases in heat pumps and small air conditioning units. Heat pumps, pivotal in mitigating climate change, are expected to see a significant rise in residential applications. However, R134a, widely employed in these systems, has a high GWP of 1530, highlighting the need for more eco-friendly substitutes. Hydrofluoroolefins (HFOs) and natural fluids, particularly hydrocarbons (HCs), have emerged as promising fourth-generation refrigerants due to their negligible ozone depletion potential (ODP) and very low global warming potential (GWP). Despite the potential of these new refrigerants, an optimal replacement for R134a in heat pumps has yet to be found. In this regard, this study investigates the potential of the low-GWP HFO/HC mixture R1234yf/R600a (0.85/0.15) as a drop-in replacement for R134a in water-to-water heat pumps. The research conducts a comparative analysis between R134a and the nearly-azeotropic mixture, assessing their performance under identical heating conditions across 20 different combinations of heat sink and heat source temperatures, ranging from 35 °C to 70 °C and from 10 °C to 20 °C respectively. The R1234yf/R600a mixture exhibited a lower pressure ratio and higher mass flow rates compared to R134a. Additionally, the mixture showed favorable performance in terms of power consumption and compressor outlet temperatures, with slightly lower COP compared to the baseline fluid. These findings suggest that with proper optimization, the R1234yf/R600a mixture could be a viable and sustainable alternative to R134a in residential heat pump applications
Recasting experimental constraints on relativistic magnetic monopoles
No full textMagnetic monopoles with masses up to 1014 GeV can be accelerated to relativistic velocities in Galactic and
intergalactic magnetic fields. The cosmic flux of relativistic monopoles is constrained by various experiments,
with the limits given as functions of the monopole velocity (Lorentz factor) at the detectors. The velocity,
however, is usually treated as a free parameter due to the ambiguity in the computation of the acceleration
before the monopoles arrive at Earth. We explicitly evaluate the velocity by exploiting recent studies on cosmic
magnetic fields and the monopole acceleration therein, to recast experimental limits in terms of the mass of
monopoles. By applying our method to various terrestrial experiments, including the Pierre Auger Observatory,
IceCube, MACRO, and the upcoming Cherenkov Telescope Array Observatory, as well as to astrophysical
constraints, we report limits on the flux of monopoles for a wide range of monopole masses. We also highlight
the role of monopoles as messengers of cosmic magnetic fields, and discuss the possibility of using monopole
experiments to probe intergalactic magnetic field