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Aim: Striatin (Strn) is a scaffold protein expressed in cardiomyocytes (CMs) and alteration of its expression are described in various cardiac diseases. However, the alteration underlying its pathogenicity have been poorly investigated. Methods: We studied the role(s) of cardiac Strn gene (STRN) by comparing the functional properties of CMs, generated from Strn‐KO and isogenic WT mouse embryonic stem cell lines. Results: The spontaneous beating rate of Strn‐KO CMs was faster than WT cells, and this correlated with a larger fast INa conductance and no changes in If. Paced (2–8 Hz) Strn‐KO CMs showed prolonged action potential (AP) duration in comparison with WT CMs and this was not associated with changes in ICaL and IKr. Motion video tracking analysis highlighted an altered contraction in Strn‐KO CMs; this was associated with a global increase in intracellular Ca2+, caused by an enhanced late Na+ current density (INaL) and a reduced Na+/Ca2+ exchanger (NCX) activity and expression. Immunofluorescence analysis confirmed the higher Na+ channel expression and a more dynamic microtubule network in Strn‐KO CMs than in WT. Indeed, incubation of Strn‐KO CMs with the microtubule stabilizer taxol, induced a rescue (downregulation) of INa conductance toward WT levels. Conclusion: Loss of STRN alters CMs electrical and contractile profiles and affects cell functionality by a disarrangement of Strn‐related multi‐protein complexes. This leads to impaired microtubules dynamics and Na+ channels trafficking to the plasma membrane, causing a global Na+ and Ca2+ enhancement. [ABSTRACT FROM AUTHOR]

The water-cooled lithium-lead breeding blanket is a candidate option for the European Demonstration Power Plant (DEMO) nuclear fusion reactor. This breeding blanket concept relies on the liquid lithium-lead as breeder-multiplier, pressurized water as coolant, and EUROFER as structural material. The current design is based on DEMO 2015 specifications and represents the follow-up of the design developed in 2015. The single-module-segment approach is employed. This is constituted by a basic geometry repeated along the poloidal direction. The power is removed by means of radial-toroidal (i.e., horizontal) water cooling tubes in the breeding zone. The lithium-lead flows in a radial-poloidal direction. On the back of the segment, a 100-mm-thick plate is in charge of withstanding the loads due to normal operation and selected postulated initiating events. Water and lithium-lead manifolds are designed and integrated with a consistent primary heat transport system, based on a reliable pressurized water reactor operating experience, and the lithium-lead system. Rationale and features of the single-module-segment water-cooled lithium-lead breeding blanket design are discussed and supported by thermo-mechanic, thermo-hydraulic, and neutronic analyses. Preliminary integration with the primary heat transfer system, the energy storage system, and the balance of plant is briefly discussed. Open issues, areas of research, and development needs are finally pointed out. @EUROfusion Consortium*, 2017. *For more details see http://www.euro-fusionscipub.org/disclaimer-copyright [ABSTRACT FROM AUTHOR]

In the framework of the archaeometric research on Apulian Late Antique glass, a collection of 24 glass vessels (third to seventh centuries ad) and production indicators found at Herdonia (Foggia, Italy) was examined, by means of SEM-EDS, EMPA, ICP-MS and LA-ICP-MS. A fragment of crucible was further investigated by SEM-EDS and EMPA. The results obtained were discussed together with another glass collection from Herdonia previously investigated. The full set of 48 samples was made of siliceous sands mixed with plant ashes (two samples: a dark green slab and a colourless beaker/lamp) or natron (all the other 46 samples). The latter were assigned to the following compositional groups: HIMT, Levantine 1, RNCBGY1, RNCBGY2, RC/LAC-Sb, intermediate HIMT/RNCBGY1, intermediate RNCBGY1/HIMT, intermediate Levantine/RNCBGY2 and two other groups, the CaO-rich HIMT and the CaO-rich/Na2O poor HIMT, which showed a prevailing Adriatic distribution and a close similarity to the weak HIMT glass group. Most Herdonia samples were similar to the HIMT productions, and thus of likely Egyptian origin, while a smaller number of samples referred to the Levantine productions. [ABSTRACT FROM AUTHOR]

Thirty-two glass objects (third to ninth centuries ad) have been investigated by means of SEM-EDS, EMPA, ICP-MS and LA-ICP-MS. Siliceous sands and natron were identified as the vitrifying and the fluxing agents, respectively. Colouring agents were iron for yellow/-green, aqua blue and blackish glass; cobalt for blue and, combined with iron, for brownish glass; and copper and lead antimonates for one emerald green glass. Antimony was the main decolourizer, while manganese was rarely used or effective. Half of the collection was probably of Levantine origin, while the other half was assigned to the North African coast (Egypt?). The reliability of the CaO-rich HIMT glass group has been consolidated. [ABSTRACT FROM AUTHOR]

The latest versions of RELAP5-3D© code allow the simulation of thermodynamic system, using different type of working fluids, that is, liquid metals, molten salt, diathermic oil, and so forth, thanks to the ATHENA code integration. The RELAP5-3D© water thermophysical properties are largely verified and validated; however there are not so many experiments to generate the liquid metals ones in particular for the Lead and the Lead Bismuth Eutectic. Recently, new and more accurate experimental data are available for liquid metals. The comparison between these state-of-the-art data and the RELAP5-3D© default thermophysical properties shows some discrepancy; therefore a tool for the generation of new properties binary files has been developed. All the available data came from experiments performed at atmospheric pressure. Therefore, to extend the pressure domain below and above this pressure, the tool fits a semiempirical model (soft sphere model with inverse-power-law potential), specific for the liquid metals. New binary files of thermophysical properties, with a detailed mesh grid of point to reduce the code mass error (especially for the Lead), were generated with this tool. Finally, calculations using a simple natural circulation loop were performed to understand the differences between the default and the new properties. [ABSTRACT FROM AUTHOR]

Aims: Nfix is a transcription factor belonging to the Nuclear Factor I (NFI) family comprising four members (Nfia, b, c, x). Nfix plays important roles in the development and function of several organs. In muscle development, Nfix controls the switch from embryonic to fetal myogenesis by promoting fast twitching fibres. In the adult muscle, following injury, lack of Nfix impairs regeneration, inducing higher content of slow-twitching fibres. Nfix is expressed also in the heart, but its function has been never investigated before. We studied Nfix role in this organ., Methods: Using Nfix-null and wild type (WT) mice we analyzed: (1) the expression pattern of Nfix during development by qPCR and (2) the functional alterations caused by its absence, by in vivo telemetry and in vitro patch clamp analysis., Results and Conclusions: Nfix expression start in the heart from E12.5. Adult hearts of Nfix-null mice show a hearts morphology and sarcomeric proteins expression similar to WT. However, Nfix-null animals show tachycardia that derives form an intrinsic higher beating rate of the sinus node (SAN). Molecular and functional analysis revealed that sinoatrial cells of Nfix-null mice express a significantly larger L-type calcium current (Cacna1d + Cacna1c). Interestingly, downregulation of Nfix by sh-RNA in primary cultures of neonatal rat ventricular cardiomyocytes induced a similar increase in their spontaneous beating rate and in I CaL current. In conclusion, our data provide the first demonstration of a role of Nfix that, increasing the L-type calcium current, modulates heart rate., (© 2023 The Authors. Acta Physiologica published by John Wiley & Sons Ltd on behalf of Scandinavian Physiological Society.)