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Theory-agnostic searches for non-gravitational modes in black hole ringdown
No full textIn any extension of General Relativity (GR), extra fundamental degrees of freedom couple to gravity. Besides deforming GR forecasts in a theory-dependent way, this coupling generically introduces extra modes in the gravitational-wave signal. We propose a novel theory-agnostic test of gravity to search for these nongravitational modes in black hole merger ringdown signals. To leading order in the GR deviations, their frequencies and damping times match those of a test scalar or vector field in a Kerr background, with only amplitudes and phases as free parameters. By applying this test to GW150914, GW190521, and GW200129, we find no strong evidence for an extra mode; however, its inclusion modifies the inferred distribution of the remnant spin. This test will be applicable for future detectors, which will achieve signal-to-noise ratios higher than 100 (and as high as 1000 for space-based detectors such as LISA). Such sensitivity will allow measurement of these modes with amplitude ratios as low as 0.02 for ground-based detectors (and as low as 0.003 for LISA), relative to the fundamental mode, enabling stringent agnostic constraints or detection of scalar/vector modes
Alterazioni microvascolari retiniche e coriocapillari nei pazienti con early Alzheimer: potenzialità diagnostiche dell’OCTA
No full textLa malattia di Alzheimer (AD) è una patologia neurodegenerativa progressiva caratterizzata dall’accumulo di β-amiloide nel parenchima cerebrale e da alterazioni neurovascolari diffuse. Nonostante i progressi nella diagnostica per immagini e nei biomarcatori liquorali, rimane urgente l’esigenza di individuare un marcatore affidabile, non invasivo e facilmente applicabile nella pratica clinica, in particolare nelle fasi precliniche e iniziali della malattia.
Poiché la retina condivide con il cervello la stessa origine embriologica e caratteristiche istologiche simili, essa rappresenta una finestra privilegiata sul sistema nervoso centrale. Alterazioni microvascolari retiniche e della coriocapillare, analoghe a quelle osservate nel tessuto cerebrale, sono state descritte in soggetti affetti da Alzheimer, suggerendo che l’imaging oculare possa riflettere precocemente i processi neurodegenerativi cerebrali.
Scopo del presente studio è stato quello di analizzare, mediante Optical Coherence Tomography Angiography (OCTA), le caratteristiche morfologiche e funzionali della microvascolarizzazione retinica e della coriocapillare in pazienti affetti da Alzheimer in fase precoce, al fine di valutare la presenza di alterazioni vascolari significative rispetto a soggetti sani di controllo.
Sono stati arruolati 18 pazienti con diagnosi di Alzheimer precoce (gruppo di studio) e 18 soggetti sani di età comparabile (gruppo di controllo). Tutti i partecipanti sono stati sottoposti a una valutazione neurologica e neuropsicologica completa, comprendente test cognitivi standardizzati, e a un esame oftalmologico approfondito con acquisizione di scansioni OCTA ad alta risoluzione. Le analisi si sono focalizzate sulla densità vascolare dei plessi capillari retinici e sull’area di flusso della coriocapillare, utilizzando un’area foveale automatizzata centrata sulla macula.
L’analisi statistica ha mostrato una riduzione significativa dell’area di flusso della coriocapillare nei pazienti con Alzheimer precoce rispetto ai soggetti di controllo (p = 0,006), indicativa di un’alterazione della perfusione coroideale nelle fasi iniziali della malattia. Sebbene le modificazioni nei plessi capillari retinici non abbiano raggiunto la significatività statistica, si è osservata una tendenza alla riduzione della densità vascolare superficiale, coerente con un quadro di compromissione microcircolatoria progressiva.
I risultati ottenuti forniscono ulteriori evidenze del coinvolgimento della microvascolarizzazione retinica e coroideale nella malattia di Alzheimer. L’OCTA emerge come una metodica diagnostica promettente e non invasiva, capace di rilevare precocemente alterazioni vascolari correlate al processo neurodegenerativo. Ulteriori studi con campioni più ampi, disegni longitudinali e software OCTA di nuova generazione sono necessari per definire con maggiore precisione il ruolo di tali modificazioni vascolari come biomarcatori di Alzheimer e per valutare il loro potenziale impiego nello screening e nel monitoraggio clinico della malattia.Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of β-amyloid in the brain and widespread neurovascular dysfunction. Despite significant advances in neuroimaging and cerebrospinal fluid biomarkers, there is an urgent need for a reliable, non-invasive, and easily applicable biomarker, particularly for the preclinical and early stages of the disease.
The retina shares the same embryologic origin and histological characteristics as the brain, making it an accessible and representative extension of the central nervous system. Microvascular alterations of the retina and choriocapillaris, similar to those described in cerebral tissue, have been reported in Alzheimer’s patients, suggesting that ocular imaging may serve as an early indicator of cerebral neurodegenerative processes.
Objective: The aim of the present study was to analyze, through Optical Coherence Tomography Angiography (OCTA), the morphological and functional characteristics of the retinal and choriocapillaris microvasculature in patients with early Alzheimer’s disease, in order to identify possible vascular alterations compared with age-matched healthy controls.
Methods: A total of 18 patients with early Alzheimer’s disease (study group) and 18 healthy age-matched subjects (control group) were enrolled. All participants underwent a comprehensive neurologic and neuropsychological assessment, including standardized cognitive tests, as well as a full ophthalmologic examination with high-resolution OCTA scans. Quantitative analyses focused on the vessel density of the superficial and deep retinal capillary plexuses and on the choriocapillaris flow area, calculated within an automatically generated fovea-centered circular region.
Results: A significant reduction of the choriocapillaris flow area was observed in the Alzheimer’s group compared with healthy controls (p = 0.006), indicating impaired choriocapillaris perfusion in the early stages of the disease. Although differences in retinal capillary plexuses did not reach statistical significance, a trend toward decreased superficial capillary density was noted, consistent with an evolving microvascular impairment.
Conclusions: These findings provide further evidence of retinal and choroidal microvascular involvement in Alzheimer’s disease. OCTA emerges as a promising, non-invasive diagnostic tool capable of detecting early vascular changes associated with neurodegeneration. Future research involving larger cohorts, longitudinal designs, and advanced OCTA software is warranted to further clarify the role of these vascular alterations as potential biomarkers of Alzheimer’s disease, and to explore their application in clinical screening and disease monitoring
Sex and gender-related differences in neurological diseases: current challenges and recommendations for clinical practice
No full text: Neurological diseases include a large variety of conditions ranging from inflammatory, vascular and neurodegenerative disorders to epilepsy and headache. The impact of sex and gender on various aspects of these conditions (epidemiology, risk factors, pathophysiology, clinical features, treatment, and management of pregnancy and breastfeeding) is still not entirely taken into consideration, despite a rapidly increasing body of evidence. This position paper covers six neurological conditions (Alzheimer's Disease, Cerebrovascular disease, Parkinson's disease, Epilepsy, Headache disorders, Multiple Sclerosis) providing an overview of available evidence on sex and gender differences, identifying knowledge gaps and providing recommendations for clinical practice and future studies. We recommend taking into consideration modifiable sex and gender specific risk factors, the role of hormones across women's lifespan and a personalized treatment approach based on gender. We also recommend that future efforts should be devoted to increase the representation of women in clinical studies, to promote sex and gender-based guideline production and to better characterize the safety profile in pregnancy of newer drugs
Impact of the Window Ratio on the Energy Demand of Twelve Buildings in Barcelona
No full textThe glazed surface throughout the building envelope influences the energy demand of a building. In this paper, we propose the window-to-volume ratio (WVR) indicator, in contrast with the window-to-wall ratio (WWR) indicator, to evaluate the energy impact of glazing on the building envelope. The WVR indicator relates the glazed surface on facades to the total surface area of the built envelope. We consider the total built envelope as the sum of the facades, roof, surfaces in contact with other buildings, and surfaces in contact with the ground. We compared the WVR and WWR indicators for twelve existing buildings in different parts of Barcelona, a city with a Mediterranean climate. Case studies of residential buildings have volumes less than 5,000 m3, and office buildings have volumes between 30,000 m3 and 150,000 m3.The ARCHISUN software was used to simulate the annual energy demand (kWh/year) of each case study. We analyzed the indicator’s values in relation to the simulated annual energy demands. The results showed a higher correlation between WVR values and the simulated energy demand of almost all buildings, especially those with larger volumes. The WVR indicator could be used as a tool to pre-size the energy demand of buildings
m-Eternal Domination and Variants on Some Classes of Finite and Infinite Graphs
No full textWe study the m-Eternal Domination problem, which is the following two-player game between a defender and an attacker on a graph: initially, the defender positions k guards on vertices of the graph; the game then proceeds in turns between the defender and the attacker, with the attacker selecting a vertex and the defender responding to the attack by moving a guard to the attacked vertex. The defender may move more than one guard on their turn, but guards can only move to neighboring vertices. The defender wins a game on a graph G with k guards if the defender has a strategy such that at every point of the game the vertices occupied by guards form a dominating set of G and the attacker wins otherwise. The m-eternal domination number of a graph G is the smallest value of k for which (G, k) is a defender win.
We show that m-Eternal Domination is NP-hard, as well as some of its variants, even on special classes of graphs. We also show structural results for the Domination and m-Eternal Domination problems in the context of four types of infinite regular grids: square, octagonal, hexagonal, and triangular, establishing tight bounds
Academic resilience and policy reform in Italy
No full textThis chapter examines the impact of the COVID-19 pandemic on the Italian education system, analyzing both cognitive learning loss and the deterioration of non-cognitive skills. Italy's highly tracked system, with early selection at age 14 into academic (licei), technical, or vocational pathways, already exacerbated socioeconomic inequalities, which were intensified by the pandemic. Extended school closures—among the longest in the West—and a shift to remote learning led to significant, uneven learning losses. Standardized test (INVALSI) data from 2019–2024 reveal sustained deficits in core competencies, particularly in mathematics and Italian literacy, with older upper-secondary students (grade 13) experiencing the most severe declines. In contrast, English language skills improved, potentially due to increased digital media exposure.
The analysis highlights stark regional disparities, with under-resourced Southern Italy disproportionately affected, and a widening of existing gaps between academic tracks and socioeconomic groups. Furthermore, the chapter documents a profound crisis in student well-being. Comparative PISA data (2018 vs. 2022) shows a significant decline in school belonging, increased feelings of loneliness, and reduced overall life satisfaction, especially among disadvantaged students. Remote learning eroded crucial peer interactions and strained socioemotional development.
Italy’s policy response prioritized infrastructural modernization and digital device distribution but lacked a coordinated national strategy for targeted academic recovery or socioemotional support. Interventions were fragmented, reactive, and insufficiently evaluated. The authors conclude that the pandemic exposed and amplified systemic weaknesses. They argue for a dual-horizon policy approach: immediate, targeted tutoring and mental health support for recovery, coupled with long-term structural reforms. These include postponing early tracking, systematically integrating socioemotional learning into curricula, bridging the digital divide, and establishing robust monitoring systems to build a more equitable and resilient education system
Un approccio green per il trattamento dei composti fenolici nei reflui oleari: biocatalizzatore laccasi–trebbia di birra delignificata
No full textGli enzimi, grazie alla loro capacità di catalizzare reazioni specifiche con elevata efficienza, sono utilizzati spesso in applicazioni biotecnologiche. Tra questi, laccasi è un enzima della famiglia delle ossidoreduttasi multi rame, in grado di ossidare composti fenolici e aromatici accoppiando la riduzione dell’ossigeno molecolare ad acqua, e quindi spesso utilizzata per applicazioni di bioremediation e in green chemistry. L’impiego industriale delle laccasi in forma libera risulta però essere limitato dalla difficoltà di recupero dell’enzima e quindi anche dal costo di produzione. In questo lavoro di ricerca è stata studiata la capacità catalitica di un sistema basato sulla laccasi immobilizzata per adsorbimento fisico su cellulosa estratta da trebbia di birra delignificata (Delignified Spent Grain, DSG). L’obiettivo finale è stato la valutazione dell’efficacia del sistema nella degradazione dei composti fenolici presenti nei reflui oleari (Olive Mill Waste Water, OMWW), che ancora oggi rappresentano una sfida aperta nello smaltimento di questa tipologia di rifiuti. L’utilizzo di trebbia di birra trattata come supporto per l’immobilizzazione ha permesso la sintesi del sistema partendo da un materiale altamente disponibile come scarto industriale e completamente biodegradabile. Il supporto cellulosico è stato ottenuto mediante trattamento acido–basico della trebbia di birra, che oltre a degradare la lignina ha conferito un’elevata porosità alla struttura in superfice. Tali caratteristiche sono state avvalorate dall’analisi SEM (Scanning Electron Microscope), che ha rivelato una morfologia più irregolare e costellata di microcavità, condizioni particolarmente propizie all’adsorbimento enzimatica. La fase di immobilizzazione della laccasi per adsorbimento è stata affinata variando i parametri operativi più rilevanti: rapporto enzima/supporto, pH, temperatura e durata dell’incubazione. Le prove di degradazione, condotte sia su campioni standardizzati di polifenoli sia su campioni reali di reflui oleari, hanno messo in evidenza una capacità degradativa leggermente inferiore dell’enzima immobilizzato rispetto alla laccasi libera, probabilmente per la minore libertà di diffusione dell’enzima fissato. Dopo 24 ore di trattamento, la laccasi immobilizzata ha abbattuto in media circa il 70 % dei composti fenolici, contro valori superiori all’80 % per la laccasi libera. Sebbene l’efficienza diminuisca, il vantaggio di poter riutilizzare il sistema per più cicli consecutivi lo bilancia: nei test su campioni reali il biocatalizzatore ha conservato più del 40 % della capacità degradante iniziale anche dopo sei cicli di utilizzo, prolungando la durata complessiva a oltre 150 ore di funzionamento. Queste prestazioni, unite alla semplicità del processo di preparazione e al basso costo dei materiali, rendono il biocatalizzatore DSG–laccasi un’alternativa concreta e sostenibile ai tradizionali metodi chimici o fisico-chimici per il trattamento dei reflui fenolici. Complessivamente, i risultati dimostrano che la laccasi immobilizzata su trebbia delignificata tramite adsorbimento costituisce un biocatalizzatore efficiente, stabile e sostenibile, capace di mantenere buone prestazioni catalitiche anche in matrici complesse come i reflui oleari. Questo sistema si inserisce all’interno dei numerosi studi che cercano di trovare soluzioni per la riduzione dell’impatto ambientale dei reflui, tramite l’utilizzo di materiali rinnovabili provenienti da scarti industriali, allineati ai principi della chimica verde e dell’economia circolare. I risultati ottenuti gettano le basi per ulteriori sviluppi in ottica del possibile scaling up industriale e per l’integrazione del biocatalizzatore in processi di depurazione enzimatica
Identifying early structural biomakers of prodromal dementia with Lewy bodies. Preliminary evidence from voxel-based morphometry
No full textObjectives: Dementia with Lewy bodies (DLB) is a complex neurodegenerative disorder, and the identification of reliable biomarkers in its prodromal phase (pro-DLB) remains challenging. As non-invasive magnetic resonance imaging (MRI) biomarkers are still considered potential, this ongoing study aims to characterize brain alterations in pro-DLB compared to the healthy population and prodromal Alzheimer’s disease (AD), with a specific focus on the distinct clinical presentations of pro-DLB: mild cognitive impairment (MCI-DLB) and psychiatric onset (PSY).
Methods: We recruited 54 patients (20 MCI-DLB, 20 MCI-AD, 14 PSY) and 15 healthy controls (HC). All participants underwent structural and functional MRI. A preliminary Surface-Based Morphometry (SBM) analysis was performed using CAT12 within SPM12. Cortical thickness (CTh) differences among groups were assessed via one-way ANOVA.
Results: SBM analysis revealed no significant CTh reductions in either MCI-DLB or PSY patients relative to HC, with similar CTh profiles between the two pro-DLB phenotypes. In contrast, MCI-AD showed widespread CTh reductions compared to HC. A relative preservation of CTh was observed in MCI-DLB and PSY patients compared to MCI-AD patients in the bilateral parahippocampal gyrus and the right frontal pole. Furthermore, MCI-AD patients exhibited reduced CTh in the left supramarginal gyrus compared to MCI-DLB patients, and in the right rostral middle frontal cortex and left middle temporal gyrus compared to PSY patients.
Conclusions: This preliminary analysis suggests that CTh alone may not be sufficient to distinguish pro-DLB from the HC or to differentiate between pro-DLB subtypes. However, the pattern of relative CTh preservation observed in pro-DLB compared to MCI-AD may represent a supportive biomarker for differentiating these clinical populations, although it requires integration with more robust biomarkers to enhance diagnostic accuracy
Review of renewable energy-based products application for battery thermal management
No full textBattery overheating can have detrimental effects on battery performance, safety, longevity, and environmental sustainability. Implementing effective thermal management strategies and safety measures to prevent overheating and ensure the safe and reliable operation of batteries in numerous applications is decisive. Reduced battery lifespan, safety hazards, performance degradation, loss of functionality, environmental impacts, and costs of replacement or repair are the detrimental impacts of battery operation in electric cars, renewable energy storage facilities, consumer appliances, and grid-scale energy storage systems. Renewable energy-based products can be effectively utilized for Battery Thermal Management Systems (BTMS) in several ways, confirming the ideal performance, longevity, and protection of batteries. The analysis demonstrates that renewable-integrated BTMS reduced peak battery temperatures by up to 15 °C, significantly lowering the risk of thermal runaway and extending battery lifespan. Solar-powered ventilation systems decreased cooling energy consumption by nearly 70 % compared with conventional methods, while biomass-driven PCMs maintained battery temperatures below 60 °C under high C-rate discharges. By integrating renewable energy-based products for BTMS, such as solar-powered ventilation systems, geothermal cooling technologies, wind-powered ventilation/cooling systems, hydroelectric facilities, and biomass energy-driven systems, the integration of renewable energy-based products enables maintainable and systematic operation of battery systems while dropping dependence on non-renewable energy resources and diminishing environmental influence. Geothermal-PVT hybrid systems improved overall energy efficiency by 53 % and decreased total energy consumption by 25.7 %, whereas hydrogen-based cooling stabilized battery temperatures below 30.5 °C with thermal gradients under 7 °C. Hybrid RES–BTMS configurations reduced the levelized cost of energy to 0.094 USD/kWh and lowered greenhouse gas emissions by up to 3.5 million kg CO2 annually, indicating substantial environmental and economic benefits. The identified trend provides a practical pathway to attain the required specifications for environmentally benign, economic, and efficient performance. The proposed concept of renewable-energy-based BTMS enables electricity, material, and fuel production as a solution for future operations in the BTMS. A comprehensive examination of the concept has been presented in the review
La bottega di Ercole Ferrata: nuove prospettive di studio
No full textIl contributo illustra e analizza la nascita, l’organizzazione, le attività e l’eredità della bottega dello scultore Ercole Ferrata (1610 circa-1686), con un focus alla sua raccolta di oggetti d’arte e di lavoro. Grazie alla rilettura dei documenti, vengono inoltre individuati nuovi allievi