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Thermoelectric materials transform a thermal gradient into electricity. The efficiency of this process relies on three material-dependent parameters: the Seebeck coefficient, the electrical resistivity and the thermal conductivity, summarized in the thermoelectric figure of merit. A large figure of merit is beneficial for potential applications such as thermoelectric generators. Here we report the thermal and electronic properties of thin-film Heusler alloys based on Fe 2 V 0.8 W 0.2 Al prepared by magnetron sputtering. Density functional theory calculations suggest that the thin films are metastable states, and measurements of the power factor-the ratio of the Seebeck coefficient squared divided by the electrical resistivity-suggest a high intrinsic figure of merit for these thin films. This may arise from a large differential density of states at the Fermi level and a Weyl-like electron dispersion close to the Fermi level, which indicates a high mobility of charge carriers owing to linear crossing in the electronic bands.

Four thermally cleavable polythiophene derivatives containing carbonate and solubilizing groups were synthesized for noncovalent modification of single-walled carbon nanotubes (SWCNTs). A well-dispersed polythiophene/SWCNTs composite was obtained by adsorption of the polymer at the SWCNT surface. The solution-processed composite film exhibited solid-state thermal cleavage of the insulating solubilizing group through decarboxylation, producing an insoluble composite film. The thermally cleavable composite film was evaluated for potential application as a thermoelectric (TE) material. The electrical conductivity (σ) of the thermally treated composite film was up to 250 times higher than that of the as-prepared composite film. The increased σ contributed to an increase in the power factor (PF). The ethanol-processed composite film could be applicable for green processing of a TE material using the less-toxic solvent. The substrate-free polythiophene/SWCNTs composite film prepared by simple solvent evaporation yielded a figure-of-merit of 3.1 × 10 -2 with a PF of 28.8 μW m -1 K -2 at 25 °C. This solution-processed methodology is beneficial for the development of a flexible TE material.

Complications after transcatheter aortic valve implantation (TAVI) remain an important issue. This study aimed to evaluate the impact of systematic postprocedural multidetector computed tomography (MDCT) to detect subclinical complications after TAVI. From October 2013 to August 2015, a total of 135 patients who underwent transfemoral TAVI (n = 116) or transapical TAVI (n = 19) with Sapien XT and MDCT preprocedure and postprocedure were enrolled. Postprocedural MDCT findings were compared with the preprocedural MDCT findings. Cardiovascular complications were observed in 25.9% of patients, including 6 cases (4.5%) with major complications. Of those, clinically apparent major complications were reported in 2 cases including rupture of the sinus of Valsalva and iliac rupture. The complications in the remaining 4 cases (3.0%) included aortic dissection, aortic intramural hematoma, and left ventricular apical pseudoaneurysm, which were totally asymptomatic and only detected by MDCT. The apical pseudoaneurysm required surgical repair. Minor complications were observed in 21.5% of patients, 50% of which were subclinical. Only 1 case with femoral pseudoaneurysm required an additional procedure. Noncardiovascular findings were detected in 27.4% of patients; the most frequent were pleural effusions and atelectasis, which were predominantly observed in those treated through a transapical approach. Contrast-induced acute kidney injury after postprocedural MDCT was reported in 1 patient whose clinical course was complicated by sepsis. In conclusion, postprocedural MDCT was useful in detecting important subclinical complications that may affect the clinical course without deterioration of renal function., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: In patients with myocardial infarction (MI), microvascular obstruction (MVO) determined by cardiac magnetic resonance imaging (CMR) is associated with left ventricular (LV) remodeling and worse prognosis.Methods and Results:In 71 patients with ST-segment elevation MI (STEMI) treated by primary percutaneous coronary intervention (PCI), speckle tracking echocardiography (STE) and CMR were performed early after PCI. All patients underwent CMR at 6 months after hospital discharge to assess the occurrence of LV remodeling. The values of 3-dimensional (3D)-circumferential strain (CS), area change ratio (ACR), and 2-dimensional (2D)-CS were significantly different for the transmural extent of infarct, whereas the values of 3D- and 2D- longitudinal strain (LS) were not significantly different. In transmural infarct segments, the values of 3D-CS and ACR were significantly lower in segments with MVO than in those without MVO. At 6-month follow-up, LV remodeling was observed in 22 patients. In multivariable logistic regression models, global 3D-CS and ACR were significant determinants of LV remodeling rather than the number of MVO segments., Conclusions: Regional 3D-CS and ACR reflected the transmural extent of infarct and were significantly associated with the presence of MVO. In addition, global 3D-CS and ACR were preferable to the extent of MVO in the prediction of LV remodeling.

Very late stent thrombosis (VLST) is a serious complication after percutaneous coronary intervention. However, the best therapy for VLST with late-acquired incomplete stent apposition and incomplete neointimal coverage remains unknown. In these cases, neointimal coverage was nearly complete and no late-acquired malapposition was detected at 18 months after Endeavor zotarolimus-eluting stent (ZES) implantation for the treatment of VLST with late-acquired incomplete stent apposition after sirolimus-eluting stent implantation. We presented that Endeavor ZES implantation may become an attractive therapeutic strategy for the treatment of VLST with late-acquired incomplete stent apposition and incomplete neointimal coverage.

Aims: This study evaluated the clinical value of myocardial contrast-delayed enhancement (DE) with multidetector computed tomography (MDCT) for detecting microvascular obstruction (MVO) and left ventricular (LV) remodelling revealed by DE magnetic resonance imaging after acute myocardial infarction (AMI)., Methods and Results: In 92 patients with first AMI, MDCT without iodine reinjection was performed immediately following successful percutaneous coronary intervention (PCI). Delayed-enhancement magnetic resonance imaging performed in the acute and chronic phases was used to detect MVO and LV remodelling (any increase in LV end-systolic volume at 6 months after infarction compared with baseline). Patients were divided into two groups according to the presence (n = 33) or absence (n = 59) of heterogeneous enhancement (HE). Heterogeneous enhancement was defined as concomitant presence of hyper- and hypoenhancement within the infarcted myocardium on MDCT. Microvascular obstruction and LV remodelling were detected in 49 (53%) and 29 (32%) patients, respectively. In a multivariable analysis, HE and a relative CT density >2.20 were significant independent predictors for MVO [odds ratio (OR) 13.5; 95% confidence interval (CI), 2.15-84.9; P = 0.005 and OR 12.0; 95% CI, 2.94-49.2; P < 0.001, respectively). The presence of HE and relative CT density >2.20 showed a high positive predictive value of 93%, and the absence of these two findings yielded a high negative predictive value of 90% for the predictive value of MVO. Heterogeneous enhancement was significantly associated with LV remodelling (OR 6.75; 95% CI, 1.56-29.29; P = 0.011)., Conclusion: Heterogeneous enhancement detected by MDCT immediately after primary PCI may provide promising information for predicting MVO and LV remodelling in patients with AMI., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.)

Background: Increased levels of uric acid (UA) have been associated with cardiovascular disease. This association is generally stronger in women than men. However, gender differences in the prognostic value of UA in patients with acute coronary syndrome (ACS) are unknown. We investigated gender differences in the relationship between UA level and the prognosis in patients with ACS., Method: This was an observational analysis of patients with ACS undergoing percutaneous coronary intervention enrolled in the Ibaraki Cardiac Assessment Study (ICAS) registry. We analyzed 1380 patients (330 women, 1050 men) with ACS who had information on UA. We assessed the association between UA and the incidence of major cardiovascular adverse events (MACE), defined as all-cause death, congestive heart failure, reinfarction, and stroke. Patients were divided according to gender-specific UA quartile., Results: The mean UA level in women was significantly lower than that in men (4.9mg/dl vs 5.9mg/dl, p<0.001). After a median duration of follow-up period of 437 days (interquartile range 222-801 days), MACE had occurred in 186 (13%) patients [56 (17%) events in women; 130 (12%) events in men]. Kaplan-Meier analysis for MACE-free survival demonstrated that a higher quartile of UA was associated with MACE in both women and men (p<0.001, p=0.002, respectively). Multivariate Cox regression analysis revealed that the highest quartile of UA, as compared with the lowest quartile of UA, was an independent predictor of MACE in women [hazard ratio (HR), 2.84; 95% CI, 1.19-6.77; p=0.018] but not in men (HR, 1.32; 95% CI, 0.66-2.64; p=0.422)., Conclusions: An increased level of UA was associated with MACE more strongly in women than in men with ACS. These results suggest that there are gender differences in the association of UA level with the prognosis in patients with ACS., (Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

We developed an original method of in situ nanoscale characterization of thermal resistance utilizing a high-resolution transmission electron microscope (HRTEM). The focused electron beam of the HRTEM was used as a contact-free heat source and a piezo-movable nanothermocouple was developed as a thermal detector. This method has a high flexibility of supplying thermal-flux directions for nano/microscale thermal conductivity analysis, and is a powerful way to probe the thermal properties of complex or composite materials. Using this method we performed reproducible measurements of electron beam-induced temperature changes in pre-selected sections of a heat-sink α-Al(2)O(3)/epoxy-based resin composite. Observed linear behavior of the temperature change in a filler reveals that Fourier's law holds even at such a mesoscopic scale. In addition, we successfully determined the thermal resistance of the nanoscale interfaces between neighboring α-Al(2)O(3) fillers to be 1.16 × 10(-8) m(2)K W(-1), which is 35 times larger than that of the fillers themselves. This method that we have discovered enables evaluation of thermal resistivity of composites on the nanoscale, combined with the ultimate spatial localization and resolution sample analysis capabilities that TEM entails.

Background: The association of Mehran risk score (MRS) with long-term prognosis in patients treated with percutaneous coronary intervention (PCI) has not been fully reported. We investigated the association between MRS and clinical outcomes in patients who underwent PCI., Methods: Study subjects comprised 2198 patients treated with PCI from the Ibaraki Cardiovascular Assessment Study multicenter registry, excluding patients receiving hemodialysis or who died within 7 days. We categorized them into 4 groups according to MRS (low-risk: ≤5; medium-risk: 6-10; high-risk: 11-16; and very high-risk: ≥16). Contrast-induced acute kidney injury (CI-AKI) was defined as an increase of 0.5mg/dL or 25% in pre-PCI serum creatinine within 1-week post procedure. We evaluated CI-AKI and major adverse cardiac and cerebrovascular events (MACCE), and defined as all-cause death, myocardial infarction, congestive heart failure, or cerebrovascular disorder (stroke or transient ischemic attack)., Results: A total of 192 (8.7%) patients developed CI-AKI. At multivariate analysis, odds ratio for CI-AKI was 4.09 (95% CI: 1.72-9.17, p=0.002) in the very high-risk group, 1.49 (95% CI: 0.89-2.42, p=0.120) in the high-risk group, and 1.08 (95% CI: 0.74-1.54, p=0.693) in the medium-risk group, as compared with the low-risk group. MACCE in the very high-risk group was more than 5-fold higher [hazard ratio (HR) 5.40, 95% CI: 2.96-9.28, p<0.001] compared with the low-risk group and was also increased in the high-risk (HR 3.72, CI: 2.59-5.32, p<0.001) and medium-risk groups (HR 1.97, CI: 1.45-2.69, p<0.001). Kaplan-Meier analysis showed that increasing risk for MACCE was seen across the groups as MRS increased (p<0.001)., Conclusion: MRS might provide potentially useful information for prediction of CI-AKI and clinical outcomes after PCI., (Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Background: Coronary plaques with positive remodeling (PR) and low-attenuation plaques (LAP) by computed tomography angiography (CTA) might be associated with plaque vulnerability. The purpose of this study was to assess the relation between coronary plaques with PR and LAP by CTA and fibrous cap thickness measured by optical coherence tomography (OCT)., Methods: We used CTA and OCT to assess 102 coronary plaques in patients with coronary artery disease (unstable angina pectoris, n=24; stable angina pectoris, n=78). Plaque characteristics were divided into three groups: 2-feature-positive plaques (PR and LAP; n=32), 1-feature-positive plaques (PR or LAP; n=20), and 2-feature-negative plaques (neither PR nor LAP; n=50). PR was defined as remodeling index (RI) of >1.05 and LAP was defined as CT density value <50HU., Results: There were significant differences between the three plaque groups with respect to fibrous cap thickness measured by OCT: 76±24μm in 2-feature-positive plaques, 154±51μm in 1-feature-positive plaques, and 192±49μm in 2-feature-negative plaques (P<0.001). The RI (1.21±0.06, 1.14±0.05, P=0.011) and the presence of thin cap fibroatheroma (TCFA) (<70-μm thickness) (75%, 15%, P=0.001) were significantly higher in UAP than in SAP patients with 2-feature-positive plaques, whereas fibrous cap thickness (68.9±24.1, 92.1±21.9μm, P<0.001) was lower in the UAP patients. In UAP patients, the presence of ring-like enhancement showed higher accuracy of 88% for detection of TCFA., Conclusions: Coronary PR and LAP by CTA were associated with the degree of fibrous cap thickness measured by OCT. CTA can non-invasively provide promising information on plaque vulnerability by identifying coronary plaque with PR and LAP, especially ring-like enhancement., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)