University of Naples Federico II
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The ovarian structure and oogenesis in the Podarcis siculus lizard: a comprehensive overview spanning over sixty years.
No full textOogenesis in oviparous vertebrates begins with a clustered gonad, a structure that may appear simple at first glance, but which conceals a certain complexity in the differentiation of follicles and the maturation of germ cells. The primordial follicle, originating from the germinal bed, undergoes a series of morphological changes involving both follicular cells and oocytes. This differentiation process requires a coordinated interplay between intrinsic factors and extrinsic signaling molecules. In this review, the process is described thanks to the research conducted over the years on the wall lizard Podarcis siculus. Overall, these studies have enabled the identification of the precise phases and molecules underlying follicular differentiation, the formulation of a hypothesis regarding the biseasonal origin of a currently annual reproductive cycle, and the recognition of the factors contributing to damage to the reproductive cycle of terrestrial oviparous vertebrates, caused by physical events such as temperature variations and chemical events such as environmental pollutants and endocrine disruptors
Arnold Toynbee, 300 Years of Anglo-Jewry (1956) https://www.academia.edu/146742185/Arnold_Toynbee_300_Years_of_Anglo_Jewry_1956_
No full textADDITIONS, INTEGRATIONS, CORRECTIONS AND SUPPLEMENTS TO THE BIBLIOGRAPHY OF ARNOLD JOSEPH TOYNBEE, No. 601, Addition to Part I, Works by Arnold J. Toynbe
Un papa e un poeta alla crociata: Pio II e Porcelio de’ Pandoni
No full textPorcelio de’ Pandoni’s De felicitate temporum divi Pii IIis a richly heterogeneous work that brings together multiple genres, voices, and intended audiences, weav-ing poetry into history, oratory, and panegyric. By invoking felicitas–a key concept in humanist discourse –the title frames Pius II’s pontificate as a divinely sanctioned new golden age, grounded in predestination and in the pope’s personal virtue, and presented through the poet’s own eyewitness stance. This essay provides a first reading of the text by examining its sustained emphasis on the crusade against the Turks, a defining focus of Pius II’s pontificate
Microgravimetric and GPR surveying for the detection of building foundations: the case of the “Basilica dello Spirito Santo” in Naples (Italy)
No full textThis study shows that microgravity investigation can be a successful strategy to detect deep buried foundation in an urban context. Specifically, we focused on the challenging archaeological and engineering case of the “Basilica dello Spirito Santo” in Naples (Italy) where the foundation system was debated in last centuries due to its complex historical development. Here we show that microgravity data, processed through the Depth from Extreme Points (DEXP) transformation, inferred a quadrangular pattern consistent with the expected foundation reinforcements. Modelling indicates that the structure is located at ∼5 m depth, shallower than originally designed. Further geophysical investigations employing Ground Penetration Radar (GPR) reveal numerous shallow voids, interpreted as crypts and burial sites, although they did not yield conclusive evidence regarding the foundation structures. This would be likely due to weak permittivity contrasts with surrounding soils. Moreover, the data suggest the presence of a deeper elongated anomaly of uncertain origin, which could represent either a geological channel-like feature or an undocumented structure. The study demonstrates the effectiveness of multimethodological approaches in complex urban archaeological contexts, providing crucial information for both cultural heritage knowledge and restoration planning
Magnetoelastic actuated motion of fine ferromagnetic particles
No full textWireless magnetic actuation offers precise control over microscopic devices, yet full planar manipulation of rigid, tethered magnetic particles remains challenging. We introduce a minimal variational model: a permanently magnetized planar ellipse anchored by two linear springs. First, we derive exact geometric conditions under which the springs can be configured so that the ellipse rotates freely without elastic penalty -producing a continuous family of zero-energy equilibria in which the ellipse's centre traces a closed loop dictated solely by spring geometry. Next, we incorporate a uniform in-plane magnetic field and prove that the equilibrium magnetization aligns uniformly with the field. In the so-called full-controllability regime -when the spring rest lengths are long enough -rotating the external field directly prescribes the ellipse's orientation: the particle follows its zero-energy trajectory to maintain magnetic alignment, achieving a global energy minimum. For shorter springs, zero-energy configurations exist over a restricted orientation range; outside this range, the ellipse is pinned at the origin. Our results yield exact criteria for planar control in this simplest magnetoelastic setting, offering clear guidelines for the design of microscale actuators and metamaterials
A systematic design method for fully submerged hydrofoil wing systems with longitudinal flight control
No full textThe maritime industry is looking for ways to decarbonize rapidly through design strategies, and technologies,
also developing solutions for eco-friendly boating. The hydrofoil technology is one of the most promising due to its high efficiency compared to traditional planing or displacing vessels. The research was focused on the
development of a systematic design method for fully submerged hydrofoil wing system with a longitudinal flight control. Starting from a reference hull model, five alternative wing configurations were designed based on geometric, hydrodynamic, and dynamic criteria. A preliminary hydrodynamic model was developed to determine the dimensions and positions of the wing systems in five different configurations. The equations of the motion were numerically implemented, and a longitudinal double PID flight control for the wing systems was developed. The configurations were designed benefiting from a parametric CAD model and simulated through transient CFD analysis at different speeds. In terms of drag, the lowest values were found for R4 (62 N) and R3 (64 N) during cruise. R1 and R0.75 were the best configurations in terms of following the flight pattern.
Furthermore, at the same speed and displacement condition, the drag estimated for R4 was more than halved, if compared to the original model (130 N)
Chrysin and Luteolin from Moroccan Propolis to Prevent Aggressive Periodontitis Caused by Aggregatibacter actinomycetemcomitans Leukotoxin: A Computer-Aided Drug Design Approach
No full textBackground: Aggregatibacter actinomycetemcomitans is a Gram-negative, facultative anaerobic, immobile oral bacterium responsible for the secretion of virulence factors, namely leukotoxin (LtxA), a large exotoxin of the RTX family that enables the bacterium to evade the immune system by destroying leukocytes, resulting in aggressive periodontitis (AP) leading to tooth loss. Methods: This study aimed to screen 106 molecules derived from Moroccan propolis in order to identify potential inhibitors of the active sites of LtxA based on molecular docking, ADMET property evaluation, and molecular dynamics (MD) simulation. Results: Epigallocatechin gallate (EGCg), used as a reference compound, showed binding energies of −6.9 kcal/mol, −6.1 kcal/mol, −6.5 kcal/mol, and −5.9 kcal/mol with the four active sites P1, P2, P3, and P4, respectively. By establishing conventional hydrogen bonds, pi-alkyl bonds, and non-covalent pi–pi bonds. Chrysin and luteolin showed favorable binding affinities with the four active sites, named as follows: P1–P4 (P1–chrysin = −7.5 kcal/mol; P2–chrysin = −7.9 kcal/mol; P3–chrysin = −8.1 kcal/mol; P4–chrysin = −6.9 kcal/mol; P1–luteolin = −7.3 kcal/mol; P2–luteolin = −7.6 kcal/mol; P3–luteolin = −8.1 kcal/mol; P4–luteolin = −7.3 kcal/mol). The binding affinity of these two propolis derivatives was stabilized by pi−sigma bonds, pi−alkyl bonds, conventional hydrogen bonds, pi-cation interactions, non-covalent pi–pi bonds, and carbon–hydrogen bonds. According to free energy calculations performed with Prime MM-GBSA, the complexes formed by chrysin demonstrated the most stable interactions due to Van der Waals and lipophilic forces. Luteolin formed significant interactions, but slightly weaker than those of chrysin. These results reveal the inhibitory potential of chrysin and luteolin with protein active sites. MD simulations corroborated the excellent stability of complexes formed by chrysin, as indicated by low RMSD values, suggesting favorable dynamic behavior. Conclusions: These results highlight the potential of chrysin as a versatile inhibitor capable of interacting with the four active sites. These findings are a strong foundation for further experimental confirmations
Subcutaneous Tumor Tract Seeding After Percutaneous Ablation for Clear Cell Renal Cell Carcinoma: A Case Report and Literature Review
No full text: Background and Clinical Significance: Percutaneous ablation is an increasingly used nephron-sparing treatment for small renal masses (SRMs). Although generally considered safe, tumor seeding along the applicator tract is rare (<0.1%) and may be underreported. This study reviews the existing literature to synthesize patterns, potential risk factors, and clinical presentation of this complication following percutaneous thermal ablation of renal cell carcinoma (RCC). Case Presentation: We report the case of an 84-year-old man who developed late subcutaneous abdominal-wall tumor seeding more than ten years after nephron-sparing surgery for a T1a renal mass and following three sessions of percutaneous cryo- and microwave ablation for recurrent clear-cell renal cell carcinoma (ccRCC). The lesion was surgically excised, and histology confirmed ccRCC with negative margins. A descriptive literature review was conducted using PubMed and ScienceDirect to identify English-language case reports and case series (CS) documenting tumor seeding after RCC percutaneous ablation. Eight studies involving nine patients met the inclusion criteria. The median age was 66 years (interquartile range [IQR] 64-74; range 47-84). The median follow-up duration was 11 months (IQR, 4.5-18.5; range 3-60), and the median interval to tumor seeding was 11 months (IQR, 6-18.5; range 3-60). Management included surgical excision (50%), repeat cryoablation (25%), and systemic therapy or supportive care (25%). Conclusions: Tumor tract seeding following percutaneous ablation for RCC is rare, with variable latency and presentation. Procedural factors such as the absence of tract ablation, multiple probe passes, and intra-procedural biopsy may increase risk. Awareness of this complication and long-term surveillance should be incorporated into follow-up protocols. Despite this risk, percutaneous ablation remains a safe and effective option for appropriately selected patients