Evaluation of flow dynamics in distal stent graft-induced new entry using 4D flow MRI.

Distal stent graft-induced new entry may occur after stent grafting for aortic dissection. Four-dimensional magnetic resonance imaging is useful for predicting outcomes, showing accelerated flow and increased wall shear stress, indicating further false lumen expansion.

[Determination of Endograft Size in Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury:Report of a Case].

Although the efficacy of thoracic endovascular aortic repair( TEVAR) for blunt thoracic aortic injury (BTAI) has been reported, the determination of the proper endograft size for TEVAR in BTAI cases is yet to be established. The management of BTAI by TEVAR may not be effective if a wrong endograft size is selected, possibly leading to fatal outcomes. In this case report, a hemodynamically unstable patient with BTAI was saved by TEVAR, and the preoperative and postoperative changes in the aortic diameter were compared. In TEVAR for BTAI, the effects of hemodynamic instability should be considered and the appropriate device size should be determined based on blood pressure, pulse, and inferior vena cava diameter.

[Surgical Outcomes of Aortic Root Repair in Type A Acute Aortic Dissection].

We carried out a retrospective evaluation of the early and long-term outcomes of aortic root reconstruction for type A acute aortic dissection. Between January 2001 and March 2015, a total of 21 patients underwent aortic root reconstruction. Bentall operation was performed in 9 patients( B group) and Patch plasty of sinus of Valsalva patients was performed in 12 patients (V group). There were 3 in-hospital deaths due in the B group and 1 death due in the V group. Overall survival in the V group was 72.9% and was not significantly different from survival in the B group(66.7%). In conclusion, our study demonstrated good early and long-term outcomes for patch plasty of sinus of Valsalva for type A acute aortic dissection. There was no postoperative patch-related complication in the V group. Thus, a patch plasty of sinus of Valsalva for type A acute aortic issection may be acceptable.

Structural effects on the oxygen reduction reaction on the high index planes of Pt3Co.

The oxygen reduction reaction (ORR) has been studied on the n(111)-(111) and n(111)-(100) series of Pt3Co using a hanging meniscus rotating disk electrode (HMRDE) in 0.1 M HClO4 (n is the number of terrace atomic rows). The activity for the ORR on the n(111)-(111) series, which is estimated by the specific activity at 0.90 V (RHE) j(k), increases linearly with an increase in the step atom density d(S). On the other hand, the activity for the ORR on the n(111)-(100) series increases linearly with an increase of d(S) on the surfaces with n≥ 9. On the surfaces with n < 9, however, the activity for the ORR decreases with an increase of d(S). We find a correlation between the ORR activity and θ(OH) at the step on the assumption that all the oxide species are Pt-OH.

Quantitating the lattice strain dependence of monolayer Pt shell activity toward oxygen reduction.

Lattice strain of Pt-based catalysts reflecting d-band status is the decisive factor of their catalytic activity toward oxygen reduction reaction (ORR). For the newly arisen monolayer Pt system, however, no general strategy to isolate the lattice strain has been achieved due to the short-range ordering structure of monolayer Pt shells on different facets of core nanoparticles. Herein, based on the extended X-ray absorption fine structure of monolayer Pt atoms on various single crystal facets, we propose an effective methodology for evaluating the lattice strain of monolayer Pt shells on core nanoparticles. The quantitative lattice strain establishes a direct correlation to monolayer Pt shell ORR activity.