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This paper modeled the behavior of a double-layer adsorption column to process a current with a Syngas-like composition. The modeling was performed on Aspen Adsorption software to evaluate its performance by comparison with experimental data found in the literature. The simulation aims is to evaluate the modeled system for potential use in PSA systems for hydrogen purification from a Syngas stream, with successive simulations on different plant scales. [ABSTRACT FROM AUTHOR]

Ablation of atrial tachycardias arising from the superior portion of Crista Terminalis may be risky because of the possibility to injure the right phrenic nerve. Although few techniques for phrenic nerve displacement have been reported, their execution can be difficult, timeconsuming and expose the patient to further complications related to epicardial puncture. In our case, radiofrequency catheter ablation from the right superior pulmonary vein allowed us to successfully treat the arrhythmia without hampering the phrenic nerve integrity. [ABSTRACT FROM AUTHOR]

Puncture resistance has become one of the most requested safety features, not only for protective garments such as stab vests, but also for safety shoes and gloves. Currently, this characteristic is highly demanded in the tyre industry. Conventional protective solutions, such as metallic plates and composite inserts prove to be either bulky or ineffective. The main objective of this work is the design and validation of a novel insert resistant to puncture. This composite insert consisted of a sandwich material with shear-thickening fluid interposed as the core. The dilatancy (shear-thickening) is time-independent rheological behaviour exhibited by some non-Newtonian fluids. These fluids manifest a surge in the apparent viscosity with an increase in the shear rate. In the first part of this work, a comparison between the rheological performance of different shear-thickening fluids (STFs) based on nanosilica dispersed in glycols is presented. This analysis attempts to investigate the combinations of fillers and carriers with the highest energy-absorbing capabilities among various glycol-based colloidal STFs. In the second part, the influence of the composition of the STF on its rheological properties is analyzed statistically. Finally, the puncture resistance of a composite system obtained by encapsulating the previously manufactured shear-thickening fluids in a polymeric shell is analyzed by means of a high-speed puncture test. This test was performed on the mockup of a tyre tread containing the best performing STF. The results showed that the use of the STF core increased the resistance to puncture by 20% as compared to the same volume of tyre tread material. Furthermore, the STF hermetically sealed the pierced sample, even when the tyre mockup was inflated at high internal pressure. [ABSTRACT FROM AUTHOR]

Recent improvements in additive layer manufacturing (ALM) have provided new designs of geometrically complex structures with lighter materials and low processing costs. The use of additive manufacturing in spacecraft production is opening up many new possibilities in both design and fabrication, allowing for the reduction of the weight of the structure subsystems. In this aim, polymeric ALM structures can become a choice, in terms of lightweight and demisability, as far as good thermomechanical properties. Moreover, provided that fused-deposition modeling (FDM) is used, nanosats and other structures could be easily produced in space. However, the choice of the material is a crucial step of the process, as the final performance of the printed parts is strongly dependent on three pillars: design, material, and printing process. As a high-performance technopolymer, polyether ether ketone (PEEK) has been adopted to fabricate parts via ALM; however, the space compatibility of 3D-printed parts remains not demonstrated. This work aimed to realize a nanosat polymeric structure via FDM, including all the phases of the development process: thermomechanical design, raw material selection, printing process tuning, and manufacturing of a proof of concept of a technological model. The design phase includes the application of topology optimization to maximize mass saving and take full advantage of the ALM capability. 3D-printed parts were characterized via thermomechanical tests, outgassing tests of 3D-printed parts are reported confirming the outstanding performance of polyether ether ketone and its potential as a material for structural space application. [ABSTRACT FROM AUTHOR]

Introduction Methods Results Conclusion The dST‐Tiso is a newly proposed electrocardiographic (ECG) marker during Brugada (BrS) type I pattern, that predicts the likelihood of ventricular arrhythmia (VA) inducibility in patients with ajmaline‐induced pattern. The objective of this study was to validate the effectiveness of this criterion using an independent data set.Consecutive patients exhibiting a BrS type I ECG pattern following ajmaline administration underwent programmed ventricular stimulation (PVS). dST‐Tiso interval was measured in all patients and tested as a predictor for positive VA inducibility.Among 128 patients (median age 43 years, 59% male) with drug‐induced BrS type I ECG pattern who underwent PVS, 32 (25.0%) had VA inducibility that required defibrillation. Compared to noninducible subjects, those with positive PVS were more commonly male (81% vs. 51%, p = 0.003), had longer PQ (165 vs. 160 ms, p = 0.016) and dST‐Tiso (310 vs. 230 ms, p < 0.001) intervals, and shorter QT interval (412 vs. 420 ms, p = 0.022). When treated as a continuous variable, dST‐Tiso confirmed significant association with VA inducibility, with an adjusted odds ratio of 1.02 (95% confidence interval: 1.01–1.03, p < 0.001) for each 1 ms increase in duration. A dST‐Tiso interval >300 ms yielded a sensitivity of 75%, a specificity of 86%, and positive and negative predictive values of 69% and 91%, respectively.The validation of the model based on the dST‐Tiso interval >300 ms confirmed its high accuracy in predicting VA inducibility in drug‐induced BrS type I pattern. This straightforward ECG marker might be linked to the extent of the electrical substrate of the disease. [ABSTRACT FROM AUTHOR]

Introduction: The second-generation cryoballoon (CB) has emerged in the last decade as an effective treatment for atrial fibrillation (AF). This study sought to analyze the rate of PV reconnection following CB ablation, evaluate the most frequent PV sites of conduction recovery and finally to assess procedural and biophysical indicators of reconnection in a large cohort of patients undergoing repeat ablation for recurrence of atrial arrhythmias., Methods and Results: A total of 300 consecutive patients (189 males, 63%; mean age 63.0 ± 11.1 years) underwent a repeat ablation after 18.2 ± 10.8 months from the index CB ablation. All repeat ablations were performed using a 3-dimensional electro-anatomical mapping system. Among all 1178 PVs, 209 (17.7%) showed a late PV reconnection in 177 patients (1.18 per patient), at the time of repeat ablation procedure. Overall, persistent PV isolation could be documented in 969 of 1178 PVs (82.3%). In 123 of 300 patients (41%), persistent isolation could be demonstrated in all PVs, whereas PV reconnection could be documented in 177 patients (59%). In the multivariable analysis, nadir temperature (p = 0.03), time to PV isolation (p = 0.01) and failure to achieve - 40 °C within 60 s (p = 0.05) were independently associated with late PV reconnection., Conclusions: The rate of late PV reconnection after CB ablation was low (1.18 PVs/patient). The most frequent sites of reconnections were the superior-anterior portions for the upper PVs and the inferior-posterior portions for the lower PVs. Faster time to isolation, colder nadir temperatures and achievement of - 40 °C within 60 s were associated with durable PV isolation., Competing Interests: GBC reports speaker fees for Medtronic, Biotronik, Biosense Webster, and Abbott; teaching honoraria from Medtronic and Biotronik; proctoring honoraria from Medtronic; C.d.A. reports speaker fees for Medtronic, Biotronik, Biosense Webster, Abbott, and Boston Scientific; teaching honoraria from Medtronic, Biotronik, Abbott, and Boston Scientific; proctoring honoraria from Medtronic, Abbott, and Biotronik. Funding: research support from the Heart Rhythm Research Center., (© 2022 The Authors.)