University of Naples Federico II
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Arnold Toynbee, Japanese Pacifism is in Jeopardy (1968) (https://www.academia.edu/145720800/Arnold_Toynbee_Japanese_Pacifism_is_in_Jeopardy_1968_)
No full textADDITIONS, INTEGRATIONS, CORRECTIONS AND SUPPLEMENTS
TO THE BIBLIOGRAPHY OF ARNOLD JOSEPH TOYNBEE, No. 556, Addition to Part I,
Works by Arnold J. Toynbe
Numerical simulations for regenerator optimization in an experimental elastocaloric cooling prototype based on shape memory alloys
No full textThe SMACOOL (acronym for Shape Memory Alloy based elastocaloric CooLing system) project aims to develop a rotary elastocaloric-based air-conditioning system utilizing shape memory alloys as solid-state refrigerants. Solid-state refrigeration based on the elastocaloric effect offers a promising alternative to vapor compression systems, but it still faces major challenges such as low energy efficiency, mechanical fatigue of materials, and complex regenerator design. Addressing these issues is crucial to enable practical implementation in real cooling applications. In this study, a numerical investigation was carried out to optimize the regenerator design, comparing tension and compression loading modes and different geometries, namely parallel plates and spiral cross-sections. Model validation against experimental data and mesh independence analyses confirmed the reliability of the numerical approach. Finite element simulations revealed that compression mode outperforms tension, achieving cold-side temperature lifts up to 10 times higher and cooling powers up to 4 times higher under identical operating conditions. Spiral geometries showed up to 115% higher ΔTcold and up to 314% higher cooling power compared to parallel plates in Active elastocaloric Regenerative refrigeration cycle. In Heat Recovery cycle, the spiral regenerator achieved an increase up to: 123% for ΔTcold, 22% for cooling power and 55% for COP respect to parallel plates. The study also highlights that internal buckling prevention material negatively affects thermal performance. Based on these findings, a spiral compression regenerator was selected for the SMACOOL prototype, targeting enhanced energy efficiency and system durability
LIFR antagonism reverses epithelial pro-CAF programs in pancreatic ductal adenocarcinoma
No full textExtracellular matrix remodelling that occurs in pancreatic ductal adenocarcinoma (PDAC) is considered a promoting factor of cancer growth, immune evasion and therapeutic resistance. Cancer-associated fibroblasts (CAFs) that constitute the dominant stromal population, arise primarily from activated pancreatic stellate cells and display remarkable functional heterogeneity, encompassing inflammatory iCAFs and contractile myCAFs. Although epithelial-stromal communication is central to PDAC biology, the upstream mechanisms that prime tumour cells toward CAF-Activating cells remain incompletely defined. The leukaemia inhibitory factor (LIF), a pleiotropic cytokine of the IL-6 family, is highly expressed in PDAC and has been implicated in tumour progression. However, the role of LIF and LIF receptor (LIFR):gp130 complex in promoting CAF activation is poorly defined. Here, we combined human PDAC transcriptomics, immunofluorescence and epithelial-stromal co-culture assays to define LIF-driven pro-CAF programs and evaluate their pharmacological reversibility. In PDAC cancer cells, MIAPaCa-2 cells, LIF induced a coordinated transcriptional network encompassing inflammatory mediators, paracrine fibroblast-activating signals and ECM/mechanotransductive modules, while repressing stromal-inhibitory genes. These signatures were recapitulated in PDAC tissues, where LIF expression directly correlated with CAF markers and with stromal remodelling genes. On this background, we have developed a novel steroidal LIFR antagonist, LRI310, and evaluate its effects on LIF:LIFR axis. Exposure of PDCA cell lines to LRI310 suppresses STAT3 activation and counteracts effects of LIF on proliferation and CAF-inducing transcriptional programs. Collectively, these findings identify LIF as an important epithelial driver of CAF-oriented transcriptional programs in PDAC and support the development of LIFR antagonism as a promising strategy to modulate the desmoplastic microenvironment
Arnold Toynbee, Man’s Mark on Paradise Island [Hawaii], 1967 (https://www.academia.edu/146211630/Arnold_Toynbee_Man_s_Mark_on_Paradise_Island_Hawaii_1967)
No full textADDITIONS, INTEGRATIONS, CORRECTIONS AND SUPPLEMENTS TO THE BIBLIOGRAPHY OF ARNOLD JOSEPH TOYNBEE, No. 597, Addition to Part I, Works by Arnold J. Toynbe
Behavioral implementation by individual-based rights structures: A full characterization
No full textGas-involved photo- and electro-catalysis roadmap towards 2030
No full textThe catalytic transferred of small molecules into high-value chemical products in green methods are highly perused, and has obtained huge attention. In this field, great progress has been achieved during the past five years. Followed by the roadmap (Chinese Chemical Letters, 2019, 30, 2089–2109) written by us before five years, we think that it should be updated to give more insights in this field. Thus, we write the present roadmap based on the fast changed background. In this roadmap, oxygen and carbon dioxide reduction reactions (including at high temperature), photocatalytic hydrogen generation and carbon dioxide reduction reactions, (photo)electrocatalytic reduction of O2 to H2O2 and NH3 generated from N2 are discussed. The progress and challenges in above catalytic processes are given. We believe this manuscript will give the researchers more suggestions and help them to obtain useful information in this field
Rethinking the Indexation of Retirement Age: Cohort vs. Period Life Expectancy
No full textOver the past two centuries, life expectancy has risen steadily in industrialized countries, challenging the financial sustainability of pen-sion systems. In systems with indexed pension age, a key issue is whether to use period life expectancy (PLE) or cohort life expectancy (CLE). CLE relies on real cohort data and captures future mortality improve-ments; requiring a full lifespan of data, it can be estimated only for extinct cohorts. To address this, CLE is often estimated using life tables combining past and expected future mortality. In contrast, PLE is basedonmortalityratesobservedinasingleperiod.Itissimplerbutlessaccu-ratethanCLE,particularlywhenassessingtheretirementsystemssus-tainability.Theaimofthispaperistwofold:measuringthegapbetweenCLEandPLEatage65forItalianpopulationusingLee-CarterandRenshaw-Habermanmodelsformortalityprojections,andassessinghowthisgapaffectsthepensionageshift
Extensive experimental investigation and phenomenological modelling of a DI ultra-lean hydrogen light-duty engine: combustion analysis, NOx and unburned fuel emissions
No full textThe vehicular sector is focused on reducing engine emissions in response to national and international regulations, targeting CO2 reduction. Carbon-neutral fuels, particularly green hydrogen from renewable sources, offer a promising path forward. In this perspective, this study investigates a 2.5-L 4-cylinder spark-ignition engine directly supplied with hydrogen, designed for the light-duty transport sector. An extensive experimental campaign explores the engine behaviour under various engine speeds and torque levels, working in ultra-lean conditions (relative air/fuel ratio − λ − between 2.15 and 3.30). Experiments evidenced that leaner mixtures and higher speeds lead to longer combustion durations in both early and main stages. They underlined that the combustion centre can assume an optimal timing under medium/low load operations and must be delayed at high loads to avoid knocking cycles. NOx emissions are globally reduced and become relevant only in the conditions where λ is close to 2 (maximum torque curve). The production of unburned hydrogen (uH2) is slightly dependent on the operating conditions and becomes significant only when the combustion is less stable (minimum load). The experimental results are used for an extensive validation of the predictive phenomenology-based combustion model, considering flame propagation enhancements related to turbulence and thermo-diffusive instabilities. Additionally, refined emission models are employed to estimate levels of uH2 and NOx. Simulation results are in good agreement with the experimental global engine parameters and combustion indicators, with average errors below 2 % and 1.6 CADs, respectively. Similarly, the pressure cycles and the related burn rates are correctly reproduced, and the influence on the model predictivity of the thermo-diffusive flame instabilities is evidenced. Finally, the model demonstrates to accurately follow the variations in NOx emission over the engine operating domain, while uH2 levels are adequately captured by the simulations, with higher discrepancies in the operating points with larger combustion cyclic variability