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Cardiovascular magnetic resonance in Myocarditis: Insights into Diverse clinical presentations
No full textAims Myocarditis is an inflammatory condition with a wide spectrum of clinical presentations, ranging from low-to high-risk cases. This study aimed to evaluate the association between cardiovascular magnetic resonance (CMR) findings and different clinical presentation patterns. Material and method This retrospective study included 94 consecutive patients with acute myocarditis (74 males,78 %: mean age 37.62 ± 17.87 years) who met the diagnostic criteria for clinically suspected myocarditis with an acute presentation and underwent CMR examinations fulfilling the revised Lake Louise Criteria. The patients were stratified according to the classification proposed by Ammirati et al based on clinical parameters. Of these, 77 patients were assigned to the uncomplicated presentation category (63 males, mean age 39.10 ± 18.12 years), while 17 were classified into complicated presentation category (11 males, 65 %; mean age 30.33 ± 15.24 years) Results Patients with complicated clinical presentation demonstrated higher troponin levels (p = 0.002), lower left ventricular ejection fraction (p = 0.021), reservoir strain (p = 0.02), conduit strain (p = 0.01), global longitudinal strain (p = 0.002), and global circumferential strain (p = 0.003) compared to low-risk patients. Additionally, the complicated group exhibited a greater extent of late gadolinium enhancement (LGE) and more frequent septal involvement of LGE (p = 0.001 for both) compared to the uncomplicated group. In multivariable analysis, septal LGE emerged as the only independent discriminator between the different clinical presentation patterns (p = 0.033) Conclusion The pattern of CMR findings appears to vary among acute myocarditis patients based on their clinical presentation patterns. Septal LGE was independently associated with a higher risk profile in acute myocarditis patients
On turbulence and mixing at the top of a gravity current over a rough surface
No full textThis study investigates experimentally the effects of surface roughness on turbulence and vertical mixing at a sheared density interface forming at the top of a dense current flowing over a horizontal surface. The experiments were conducted in a water channel using the lock-exchange technique. Two cases were considered: one with a smooth channel bottom and the other with the bottom made rough by means of a series of parallelepiped elements about one-sixth the height of the dense current. Feature tracking and planar laser-induced fluorescence techniques were used to measure fluid velocity and density, respectively. Results show a general sensitivity of the mean flow and turbulence variables on surface characteristics. In the rough case, the density interface is thinner and some of the main parameters involved in the turbulence kinetic energy equation, e.g., buoyancy, production, and its dissipation rate, are higher than in the smooth case. Similarly, turbulent diffusivities of mass and momentum also depend on roughness, although their ratio remains practically unchanged going from the smooth to the rough surface. Finally, some of the results are consistent with field data and numerical simulations found in the literature
Effects of rainfall-induced torrential freshwater injections on river and lagoon sediments biogeochemistry
No full textWe investigated changes in sediment grain size, elemental (total organic C, TOC; total N, TN), isotopic (δ13C, δ15N), biochemical composition (proteins, carbohydrates, lipids, phytopigments), nutritional quality, potential degradation of sedimentary organic matter across a river-to-lagoon continuum before-after high (HRP) and low (LRP) rainfall periods. Both rainfalls relocated the coarser sediment fraction downstream in the river, whilst only the finer fraction reached the lagoon. The high swell associated to the storm preceding the LRP contributed to the seawater overwash over the outer lagoon, which masked the effects of the freshwater discharge. After the HRP, TOC and TN in the outer lagoon increased 5–6 times, whilst after the LRP both decreased 2–8 times in the whole lagoon. Rainfalls caused a δ13C enrichment (from − 27.1 to − 22.0 ‰) of the lagoon sediments and changes in the biogeochemistry of both river and lagoon sediments. After both rainfalls, time for the degradation of the biopolymeric C increased downstream the river (5–11 times) and in the outer lagoon (3 times). We conclude that the effects of rainfall-driven river runoff and their spatial extent towards the adjacent lagoon depend on the magnitude and duration of the rainfall, which differently alter sediment biogeochemistry
On the arithmetic of power monoids
No full textGiven a monoid H (written multiplicatively), the family Pfin,1(H) of all non-empty finite subsets of H containing the identity element is itself a monoid, called the reduced finitary power monoid of H, under the operation of setwise multiplication induced by H. We investigate the arithmetic of Pfin,1(H) from the perspective of minimal factorizations into irreducibles, paying particular attention to the potential presence of non-trivial idempotents. Among other results, we provide necessary and sufficient conditions on H for Pfin,1(H) to admit unique minimal factorizations
Beyond Murray’s Law: Resistance Matching Principle for Optimal Fluid Transport in Hierarchical Nanomaterials
No full textThe century-old Murray's law, originally formulated to describe optimal transport in biological vascular systems, continues to inspire the design of hierarchical nanomaterials. However, at the nanoscale, its fundamental assumptions of fluid homogeneity and negligible interfacial slip no longer hold, limiting its validity. In this work, Murray's law is extended to incorporate nanoscale effects, including slip boundary conditions and confinement-induced variations in fluid density and viscosity. Quantitative calculations reveal a transition from traditional viscous flow dominance at larger scales to interfacial slip-driven transport in microporous channels, leading to significant deviations from the original predictions of Murray's law. Furthermore, the physical foundation of the nanoscale-adapted Murray's law, namely minimum energy dissipation in nonequilibrium thermodynamics, is restated as a generalized resistance matching principle, offering a practical framework for designing hierarchical structures. This principle is experimentally validated in two structurally diverse nanosystems-biological-skeleton carbon and zeolite molecular sieves-demonstrating its broad applicability. The work provides a generalizable theoretical foundation and a practical benchmark for the rational engineering of advanced hierarchical nanomaterials. By bridging a century-old biological principle with modern nanofluidics, the proposed resistance-matching principle is expected to influence fields such as heterogeneous catalysis, membrane technology, and energy storage
Polyharmonic curves in semi-Riemannian manifolds
No full textLet ( M_t^m , g ) be a semi-Riemannian manifold of dimension m with a non-degenerate metric of index t , m ≥ 2 , 1 ≤ t ≤ m − 1 . The main aim of this paper is to investigate the existence of Frenet curves in ( M_t^m , g ) which are polyharmonic of order r , shortly, r -harmonic. We shall focus primarily on the cases that the ambient space is a semi-Riemannian space form N_t^m( c ) of sectional curvature c, a ruled Lorentzian surface or a suitable, possibly warped, product space. We shall obtain existence, non-existence and classification results
Model-based semantics: doing without meaning constitution
No full textThis paper introduces a model-based account of meaning, arguing that meaning properties reside in models rather than in the external world. Building on this view, it explores how such an instrumentalist framework can engage critically with various concerns raised by Wittgenstein, Quine, and Kripke[nstein]—each of whom voiced scepticism toward certain conceptions of semantic theorising and, in some cases, the reification of meaning. While the scope and nature of their respective criticisms may differ, the paper suggests they share a broadly deflationary attitude toward semantic metaphysics.
Twentieth-century challenges to mainstream truth-conditional semantics, from verificationism, inferentialism, and other alternatives, have further complicated the semantic landscape, prompting a reconsideration of metaphysical assumptions intheories of meaning. In light of both scepticism about meaning and explanatory disagreement in semantics, the paper questions the metaphysical interpretation of theories of meaning and proposes a reoriented understanding of semantic theorising—one that is formally tractable yet philosophically restrained
Rational structure-based design and optimization of next-generation biphenyl-piperidine-triazine derivatives as potent non-nucleoside reverse transcriptase inhibitors
No full textTo enhance the anti-resistance efficacy of our previously disclosed naphthyl-triazine 5, structure-based drug design strategy was rationally conducted to design a series of novel biphenyl-piperidine-triazine-containing non-nucleoside reverse transcriptase inhibitors. Remarkably, several of these compounds demonstrated single-digit nanomolar antiviral potency against both wild-type (WT) human immunodeficiency virus-1 (HIV-1) and five clinically relevant mutant strains. Among these, compound 11s emerged as the most potent inhibitor, showing remarkable efficacy against WT HIV-1 (50 % effective concentration (EC50) = 2 nmol/L) and five mutant strains (EC50 = 0.003–0.073 μmol/L), which was significantly superior to that of compound 5. This optimized derivative demonstrated substantially improved pharmacological properties compared to existing drugs etravirine (ETR) and rilpivirine (RPV), showing a 4-fold reduction in cytotoxicity alongside 6-fold enhancement in selectivity index (50 % cytotoxic concentration (CC50) = 19.69 μmol/L, selectivity index (SI) = 7438). The compound's metabolic profile revealed exceptional stability, with an elimination half-life (t1/2 = 41.4 min) more than double that of RPV (t1/2 = 16.03 min). Comprehensive safety evaluation indicated minimal cytochrome P450 (CYP) enzymes interference, low cardiac ion channel activity, and no observable acute toxicity, collectively suggesting a reduced risk profile for therapeutic applications. These promising characteristics significantly advance the development potential of biphenyl-piperidine-triazine derivatives as next-generation non-nucleoside reverse transcriptase inhibitors (NNRTIs), offering enhanced efficacy, improved safety, and favorable pharmacokinetic properties for antiretroviral therapy
Natural Fiber TRM Systems for Sustainable Seismic Retrofitting of Masonry Walls: An Experimental Study Using Jute Fibers
No full textThe increasing demand for sustainable and resilient construction practices in seismic areas calls for innovative retrofitting solutions utilizing renewable resources. This study presents an experimental investigation on the structural performance of masonry walls upgraded using a Natural Fiber Textile Reinforced Mortar (NFTRM) system based on jute fibers. Hollow brick masonry walls were strengthened through the application of jute fiber nets, jute-based diatons (transverse connectors), and a composite mortar incorporating 1% jute fibers by weight. In-plane cyclic shear tests were performed under constant vertical loads to evaluate the improvement in shear strength ultimate capacity. The results show that the NFTRM system significantly enhances the load-bearing performance compared to unreinforced walls, reaching an ultimate shear strength of approximately 2.7–2.9 MPa. The outcomes highlight the potential of bio-based reinforcement systems to provide an eco-friendly and effective alternative for masonry strengthening in seismic regions, promoting both sustainability and resilience