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Abstract Aims Interatrial shunts are under evaluation as a treatment for heart failure (HF); however, their in vivo flow performance has not been quantitatively studied. We aimed to investigate the fluid dynamics properties of the 0.51 cm orifice diameter Ventura shunt and assess its lumen integrity with serial transesophageal echocardiography (TEE). Methods and results Computational fluid dynamics (CFD) and bench flow tests were used to establish the flow‐pressure relationship of the shunt. Open‐label patients from the RELIEVE‐HF trial underwent TEE at shunt implant and at 6 and 12 month follow‐up. Shunt effective diameter (Deff) was derived from the vena contracta, and flow was determined by the continuity equation. CFD and bench studies independently validated that the shunt's discharge coefficient was 0.88 to 0.89. The device was successfully implanted in all 97 enrolled patients; mean age was 70 ± 11 years, 97% were NYHA class III, and 51% had LVEF ≤40%. Patency was confirmed in all instances, except for one stenotic shunt at 6 months. Deff remained unchanged from baseline at 12 months (0.47 ± 0.01 cm, P = 0.376), as did the trans‐shunt mean pressure gradient (5.1 ± 3.9 mmHg, P = 0.316) and flow (1137 ± 463 mL/min, P = 0.384). TEE measured flow versus pressure closely correlated (R2 ≥ 0.98) with a fluid dynamics model. At 12 months, the pulmonary/systemic flow Qp/Qs ratio was 1.22 ± 0.12. Conclusions When implanted in patients with advanced HF, this small interatrial shunt demonstrated predictable and durable patency and performance.

The Berlin-based initiative Weiter Schreiben was founded in 2017 by the writer Annika Reich and responds to the daunting refugee situation in contemporary Europe by encouraging collaboration between established and displaced writers living in Germany. The initiative’s objective is to foster multidirectional networks instead of one-directional support.This article explores how the organizational features of Weiter Schreiben are directly tied to its successful fostering of transnational and multilingual communities. A discussion of the initiative’s journal, (Weiter Schreiben Magazin, June, 2019) illustrates that these communities emerge through the conversation about – and the production and reception of – creative writing and other artistic endeavors. Specifically, the journal’s emphasis on locations and memories links the work of displaced writers and visual artists hailing from a range of continents and countries. My main case study is the collaborative exchange between the Syrian poet Lina Atfah who escaped Syria in 2014 and the author Nino Haratischwili who was born in Georgia and moved to Germany in 2003. The multiple forms of proximity that emerge between these two writers underscore the utter inadequacy of thinking in categories of national literatures. Inspired by Ann Rigney’s work on transnational memory and the “conjunctures” Susan Stanford Friedman observes between “‘New’ World Literature and Migration Studies,” I conclude by pondering some of the broader implications of the Weiter Schreiben initiative for the role of creative writing in an increasingly interconnected world.

Surface chemistry and interface interactions profoundly influence the properties of two‐dimensional (2D) materials and heterostructures. Therefore, developing methods to precisely control surfaces and interfaces is crucial for harnessing the properties and functions of 2D materials and heterostructures. Here, we developed a facile approach to tuning the interface distance and properties of graphene/MoS2 heterostructures (G/MoS2) by varying the functional groups attached to the surface of graphene bottom layer. We systematically investigated how different functionalized graphene bottom layers affect the interlayer distance, coupling between the interlayers, and optical properties of resulting G/MoS2 heterostructures. Our findings indicate that both the size and electron‐withdrawing/donating properties of functional groups are pivotal in regulating charge transport properties, with size playing a particularly decisive role. Our approach demonstrates an efficient and flexible pathway to regulate the interlayer spacing and charge transport, highlighting the potential of engineering interface chemistry in optimizing properties of van der Waals heterostructures. [ABSTRACT FROM AUTHOR]

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Many organic dyes are fluorescent in solution. In the solid state, however, quenching processes often dominate, hampering material science applications such as light filters, light‐emitting devices, or coding tags. We show that the dimethylene‐cyclopropanide scaffold can be used to form two structurally different types of chromophores, which feature fluorescence quantum yields up to 0.66 in dimethyl sulfoxide and 0.53 in solids. The increased fluorescence in the solid state for compounds bearing malonate substituents instead of dicyanomethide ones is rationalized by the induced twist between the planes of the cyclopropanide core and a pyridine ligand. [ABSTRACT FROM AUTHOR]

Aims: Interatrial shunts are under evaluation as a treatment for heart failure (HF); however, their in vivo flow performance has not been quantitatively studied. We aimed to investigate the fluid dynamics properties of the 0.51 cm orifice diameter Ventura shunt and assess its lumen integrity with serial transesophageal echocardiography (TEE). Methods and results: Computational fluid dynamics (CFD) and bench flow tests were used to establish the flow‐pressure relationship of the shunt. Open‐label patients from the RELIEVE‐HF trial underwent TEE at shunt implant and at 6 and 12 month follow‐up. Shunt effective diameter (Deff) was derived from the vena contracta, and flow was determined by the continuity equation. CFD and bench studies independently validated that the shunt's discharge coefficient was 0.88 to 0.89. The device was successfully implanted in all 97 enrolled patients; mean age was 70 ± 11 years, 97% were NYHA class III, and 51% had LVEF ≤40%. Patency was confirmed in all instances, except for one stenotic shunt at 6 months. Deff remained unchanged from baseline at 12 months (0.47 ± 0.01 cm, P = 0.376), as did the trans‐shunt mean pressure gradient (5.1 ± 3.9 mmHg, P = 0.316) and flow (1137 ± 463 mL/min, P = 0.384). TEE measured flow versus pressure closely correlated (R2 ≥ 0.98) with a fluid dynamics model. At 12 months, the pulmonary/systemic flow Qp/Qs ratio was 1.22 ± 0.12. Conclusions: When implanted in patients with advanced HF, this small interatrial shunt demonstrated predictable and durable patency and performance. [ABSTRACT FROM AUTHOR]

Stacked graphene oxide (GO) proton membranes are promising candidates for use in energy devices due to their proton conductivity. Identification of through‐plane channels in these membranes is critical but challenging due to their anisotropic nature. Here, we present an electrochemical reduction method for identifying and quantifying through‐plane proton channels in GO membranes. The simplicity lies in the operando optical observation of the change in contrast as GO is electrochemically reduced. Here, we find three proton‐dominated three‐phase interfaces, which are critical for the reduction reactions of GO membranes. Based on these findings, a method is proposed to identify and quantify through‐plane channels in stacked GO proton membranes using a simple three‐electrode device in combination with real‐time imaging of the membrane surface. [ABSTRACT FROM AUTHOR]

This paper discusses the promising candidate of excellent materials, graphene oxide (GO) and polyoxometalates (POMs), for radionuclide adsorbent. In this perspective, the unique properties of GO and POMs make them ideal candidates for developing new composites having the ability to adsorb radionuclides, and several essential things are reviewed. First, the anchoring mechanism to deposit POM on the GO surface area by (i) carboxylation method, (ii) covalent bonding, and (iii) impregnation method. Second, the radionuclides removal mechanism is described in several systems: (i) coagulation, (ii) electrostatic interaction, (iii) ion trapping, and (iv) H+-exchange. Third, the experimental condition that employed to enlarge the sorption capacity such as (i) pH adjustment, (ii) employing multiple oxidations, and (iii) cation charge. A thorough understanding of the POM-anchored GO material can pave the way for future research on similar materials. It can also help in understanding the nature of the interactive collaboration present between GO and POM.

The photochemical reaction of iodine and graphene induces strong new Raman modes due to the formation of trans‐oligoene substructures in graphene domains. This unique reactivity was demonstrated before on defect‐free graphene, however leaving the influence of e. g. carbon vacancies, unexplored. Here, we investigate the photochemical reaction applied on graphene with varying average distances of lattice defects and statistically analyze the characteristic Raman modes which develop with the iodination reaction. We show that the iodination reaction does not lead to Raman‐active defects and thus, the newly formed trans‐oligoene substructures do not contribute to the D‐mode of graphene. A statistical analysis reveals the correlation between the average distance of lattice defects and the intensity of the v1‐mode. For defective graphene with average defect distances below ~1 nm no new Raman modes evolve, which is the lower limit of the substructure size probed at 532 nm and explains why this observation was not possible before using common graphene oxide as graphene source. [ABSTRACT FROM AUTHOR]