Electronic Band Structure of Gallium Sulfide (GaS) with Thickness Reduction Unveiling Parabolic and Pudding Mold Band Dispersion

Metal monochalcogenides (MXs) have attracted significant interest due to their unique electronic properties, which can be tuned by varying the thickness. Gallium sulfide (GaS) stands out among MX compounds for its potential in photocatalysis, thanks to its bandgap within the visible range. However, the theoretical predictions of its band structure have not been experimentally validated until now. To bridge this gap, we performed angle-resolved photoemission spectroscopy (ARPES) measurements on bulk GaS to investigate its electronic band structure which revealed that the VBM is located at the Gamma point, and from the analysis of isoenergy contours just below the Fermi level, the contours are relatively circular and centered around the Gamma point indicating a high degree of isotropy and symmetry in the electronic states. Additionally, density functional theory (DFT) calculations revealed that the valence bands are composed of Ga 4s, Ga 4p, and S 3p orbitals, while the deeper bands are from S 3s orbitals. Furthermore, the theoretical calculations are extended to monolayer, two-layer, and three layer to observe the evolution in the band structure. Our results highlight a unique "Pudding Mold" valence band maximum (VBM) at the Gamma point, featuring multiple maxima dispersed throughout the Brillouin zone. When the GaS sample is thinned to monolayers, this band transforms into a "Pudding Mold" shape, characterized by significant corrugation at the Gamma point. This transformation predicts an increase density of states (DOS), which is highly advantageous for photocatalysis. The higher DOS enhances the absorption and utilization of visible light, which is essential in photocatalytic applications, and also provides more active sites for catalytic reactions

The First Archaeologists of Poggio Gramignano: Evidence of a Pre-Roman Settlement and the Romans Who Discovered It

The archaeological site of Poggio Gramignano, a prominent hilltop located near the southern Umbrian village of Lugnano in Teverina (TR), is well-known for the Augustan villa and the late antique infant and child cemetery found long the hill’s southwest corner. Recent fieldwork, however, has brought to light surprising new discoveries that reveal a more ancient history at Poggio Gramignano, extending the evidence for occupation back into the Orientalizing and Archaic periods. Excavation of the cemetery space has uncovered deposits that contain abundant pre-Roman artifactual material. What is more, excavation of these deposits has revealed a remarkable stratigraphic relationship between oggio Gramignano’s pre-Roman and Roman phases which suggests that the Roman builders who constructed the villa in the late 1st century BCE were in fact archaeologists of sorts themselves, having been the first to discover and interact with archaeological material from Poggio Gramignano’s pre-Roman era. In this article we first describe in detail the pre-Roman deposits and diagnostic material uncovered. We also report the recent findings of a possible a pre-Roman necropolis located near to Poggio Gramignano. Based on these findings, we offer preliminary conclusions, ypothesizing that Poggio Gramignano was once a settlement of a pre-Roman community of a hybrid culture group, possibly one with ties to the ancient Umbrian urban center of Ameria. In addition, we discuss the significance of the stratigraphic relationship between the pre-Roman and Roman phases in terms of archaeological memory, suggesting that a through-line may exist for Poggio Gramignano as a lived place

The impact of COVID-19 pandemic on hospitalization rate, clinical impairment and mortality of cirrhotic patients

: The COVID-19 pandemic caused widespread disruption to global healthcare systems, necessitating the reallocation of resources to address the immediate demands. This reorganization had significant repercussions on the management of chronic diseases, including cirrhosis. We sought to provide a comprehensive picture of the COVID-19 impact on monthly hospitalization rates of cirrhotic patients at Local Health Board 1 hospitals in the Abruzzo Region, Italy. Using the International Classification of Diseases, Ninth Revision, we identified cases of alcohol-related, nonalcohol-related, biliary, and decompensated cirrhosis. We analyzed 957 Hospital Discharge Records from January 1 to December 31, 2019 (pre-pandemic), and from January 1 to December 31, 2022 (post-pandemic). We evaluated patients' clinical impairment, length of stay, and mortality before and after the pandemic. We identified 494 hospitalizations for nonalcohol-related cirrhosis and 310 for alcohol-related cirrhosis. As key findings, hospitalizations for nonalcohol-related cirrhosis decreased (69% vs. 48%; p < .0001), while hospitalizations for alcohol-related cirrhosis increased (31% vs. 52%; p < .0001), in the post-pandemic period. Additionally, there was a significant rise in decompensated patients with alcohol-related cirrhosis post-COVID (77% vs. 65%; p = .0216). Mortality risk increased for both nonalcohol- (11% vs. 18.5%; p = .0176) and alcohol-related cirrhosis (7.7% vs. 18%; p = .0059) in the post-pandemic era. The increase in hospitalizations for alcohol-related cirrhosis is alarming and likely to have a prolonged impact on the natural history of liver diseases. There is an urgent need to reduce alcohol consumption at the population level. Continued awareness and personalized follow-up are essential for guaranteeing the standard of care during health emergencies

«Una porta aperta». L’esperienza primordiale e universale dello spazio in Raimon Panikkar

L'articolo desidera ricordare Raimon Panikkar con l’intento di riproporre la lettura dei suoi scritti., ove un elemento primario caratterizza la sua esperienza creativa: il pluriversarismo, ovvero l’orizzonte di vita sempre aperto al dialogo-dialogale e alla tolleranza intra-culturale. Tale convinzione si radica nel cuore del filosofo lungo il suo viaggio esistenziale, colorato da delicate sfumature mistiche e da numerose osservazioni filosofico-teologiche intorno all’imprescindibile connubio tra Oriente ed Occidente. Filo conduttore di questo lavoro è la considerazione dell’esperienza primordiale e universale delle «due facce della medesima realtà»: lo spazio interiore e lo spazio esteriore

Il ruolo delle aree protette nella conservazione della biodiversità vegetale e minacciata in Europa.

Biodiversity loss remains one of the most pressing environmental challenges globally, and in Europe, the Natura 2000 (N2K) protected area (PA) network plays a pivotal role in mitigating this crisis. Covering approximately 18% of the EU’s land area, the N2K network represents a cornerstone of the European Union's conservation strategy, aiming to protect priority species and habitats under the Birds and Habitats Directives. However, questions about its overall representativeness across various taxa and biogeographic regions persist. This PhD thesis explores the representativeness of N2K in biodiversity conservation through three case studies focusing on taxonomic diversity, vascular plant diversity, and forest understory plant diversity, offering a comprehensive assessment of its representativeness and performance. The first case study evaluates the impact of N2K PAs on conserving 1,769 priority species across various taxonomic groups, including mammals, birds, amphibians, reptiles, arthropods, fishes, molluscs, and vascular and non-vascular plants. Using propensity score matching to control for confounding factors related to the non-random location of PAs in the landscape the study assessed the representativeness of N2K network by comparing alpha, beta, and gamma diversity of priority species inside and outside PAs across European biogeographic regions. Results indicate that N2K PAs generally host a significantly higher number of priority species than unprotected areas. Specifically, alpha diversity was notably higher inside PAs for most taxonomic groups, except in the Boreal region. Beta diversity was also significantly higher within PAs. Similarly, gamma diversity, representing overall species richness, showed higher values in PAs, with exceptions in the Boreal and Atlantic regions. These findings underscore the uneven role of N2K across different regions and taxa, emphasizing the need for targeted expansion under the European Biodiversity Strategy for 2030 to prioritize underrepresented species and regions. The second case study focuses on the representativeness of the N2K network in conserving vascular plant biodiversity. Drawing from over 1.2 million vegetation plots in the European Vegetation Archive, encompassing 14.2 million species occurrences, the study assessed the presence of native and conservation priority species within and outside N2K sites. The findings reveal that the N2K network harbors approximately 90% of the EU’s native vascular flora, demonstrating its crucial role in conserving plant diversity. However, significant variability exists across countries and biogeographic regions. Despite this variability, N2K sites generally support a higher species richness per unit area than unprotected areas, as evidenced by species-area curves. These results highlight that while N2K is effective overall, its expansion should focus on regions and habitats where plant diversity is underrepresented, ensuring comprehensive conservation of Europe’s vascular flora. The third case study examines the representativeness of PAs (including in this case N2K sites, national parks, and reserves) in conserving forest understory plant diversity in Italy, one of Europe’s most forested and biodiverse countries. Using a dataset of 16,259 vegetation plots sampled between 1980 and 2020 in broadleaved deciduous forests, the study applied propensity score matching to control for factors related to the non-random locations of PAs and vegetation plots in the landscape. The results reveal that PAs consistently maintained higher understory plant diversity than unprotected areas. Alpha and gamma diversity showed a clear pattern, with a higher number of understory plant species found inside PAs than outside. These case studies show that while Europe's PA network is crucial for biodiversity conservation, its efficacy varies, underscoring the need for a strategic, data-driven expansion to protect underrepresented species and regions

Finding diameter-reducing shortcuts in trees

In the k-Diameter-Optimally Augmenting Tree Problem we are given a tree T of n vertices embedded in an unknown metric space. An oracle can report the cost of any edge in constant time, and we want to augment T with k shortcuts to minimize the resulting diameter. When k = 1, O(n log n)-time algorithms exist for paths and trees. We show that o(n(2)) queries cannot provide a better than 10/9-approximation for trees when k >= 3. For any constant epsilon > 0, we design a linear-time (1 + epsilon)-approximation algorithm for paths when k = o(root logn), thus establishing a dichotomy between paths and trees for k >= 3. Our algorithm employs an ad-hoc data structure, which we also use in a linear-time 4approximation algorithm for trees, and to compute the diameter of (possibly non-metric) graphs with n + k - 1 edges in time O (nk log n). (c) 2025 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)