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Much progress has been made in the nanoscale analysis of nanostructures, while the mapping of key charge transport properties such as a carrier mobility remains a challenge, especially for one-dimensional systems. Here, we report the nanoscale mapping of carrier mobilities in carbon nanotube (CNT) networks and show that charge transport behaviors varied depending on network structures. In this work, the spatial distribution of localized charge transport properties such as mobilities and charge trap densities in CNT networks were mapped via a scanning noise microscopy. The mobility map was obtained from the conductivity maps measured at different back-gate biases, showing up to two orders of mobility variations depending on localized network structures. Furthermore, from the maps, correlations between mobility/conductivity and charge trap density were analyzed to determine charge transport mechanisms. In metallic CNT networks, the regions with rather

We mapped the nanoscale reduction of resistivity and noise source activities induced by metallic single walled carbon nanotubes (m-SWCNTs) embedded in gold thin films. In this method, current and noise maps of m-SWCNTs/gold hybrid thin films were recorded using a conducting probe in contact with the surface, and the maps were utilized to estimate the nanoscale variation of resistivity (ρ) and the density distribution of noise sources (Neff) generating electrical noises in the hybrid thin film. The m-SWCNTs/gold hybrid thin films with a 5 nm thick gold layer exhibited 300% improved conductivity compared to that of pristine gold thin films. Additionally, the regions with embedded m-SWCNTs showed significantly reduced noise source densities compared with pristine gold film regions. These results clearly show that embedded m-SWCNTs improve the conductivity and reduce electrical noises of metallic electrodes. Interestingly, we observed that the ρ and the Neff on both m-SWCNTs/gold hybrid and pristine gold regions exhibited a scaling behavior of ρ ∝ Neff0.5, implying the hopping charge conduction and noise characteristics of m-SWCNTs/gold hybrid films. Our works can be a useful guideline for the development of high performance electrodes based on CNTs.

As blockchain applications are available in clouds, the resource allocation of blockchain becomes an important issue. This paper investigates the resource consumption of Hyperledger Fabric that is a popular blockchain framework. As Fabric consists of several components, this paper characterizes the resource consumption of Fabric components. Then, we attempt to control the CPU allocation of the components and explore the performance implications. Our evaluation results show that the “proper” CPU allocation of Kafka component reduces the CPU usage of the overall Fabric by 14% but the performance of Fabric does not decrease. Our result suggests that clouds can benefit from such control of CPU allocation to Fabric.

Objectives The aim of this study was to evaluate the effect of ticagrelor versus clopidogrel on left ventricular (LV) remodeling after reperfusion of ST-segment elevation myocardial infarction (STEMI) in humans. Background Animal studies have demonstrated that ticagrelor compared with clopidogrel better protects myocardium against reperfusion injury and improves remodeling after myocardial infarction. Methods In this investigator-initiated, randomized, open-label, assessor-blinded trial performed at 10 centers in Korea, patients were enrolled if they had naive STEMI successfully treated with primary percutaneous coronary intervention (PCI) and at least 6-month planned duration of dual-antiplatelet treatment. The coprimary endpoints were LV remodeling index (LVRI) (a relative change of LV end-diastolic volume) measured on 3-dimensional echocardiography and N-terminal pro–B-type natriuretic peptide level at 6 months. Results Among initially enrolled patients with STEMI (n = 336), 139 in each group completed the study. LVRI at 6 months was numerically lower with ticagrelor versus clopidogrel (0.6 ± 18.6% vs. 4.5 ± 16.5%; p = 0.095). Ticagrelor significantly reduced the 6-month level of N-terminal pro–B-type natriuretic peptide (173 ± 141 pg/ml vs. 289 ± 585 pg/ml; p = 0.028). These differences were prominent in patients with pre-PCI TIMI (Thrombolysis In Myocardial Infarction) flow grade 0. By multivariate analysis, ticagrelor versus clopidogrel reduced the risk for positive LV remodeling (LVRI >0%) (odds ratio: 0.56; 95% confidence interval: 0.33 to 0.95; p = 0.030). The LV end-diastolic volume index remained unchanged during ticagrelor treatment (from 54.7 ± 12.2 to 54.2 ± 12.2 ml/m2; p = 0.629), but this value increased over time during clopidogrel treatment (from 54.6 ± 11.3 to 56.4 ± 13.9 ml/m2; p = 0.056) (difference −2.3 ml/m2; 95% confidence interval: −4.8 to 0.2 ml/m2; p = 0.073). Ticagrelor reduced LV end-systolic volume index (from 27.0 ± 8.5 to 24.7 ± 8.4 ml/m2; p Conclusions Ticagrelor was superior to clopidogrel for LV remodeling after reperfusion of STEMI with primary PCI. (High Platelet Inhibition With Ticagrelor to Improve Left Ventricular Remodeling in Patients With ST Segment Elevation Myocardial Infarction [HEALING-AMI]; NCT02224534 )

This paper investigates the performance interference of blockchain services that run on cloud data centers. As the data centers offer shared computing resources to multiple services, the blockchain services can experience performance interference due to the co-located services. We explore the impact of the interference on Fabric performance and develop a new technique to offer performance isolation for Hyperledger Fabric, the most popular blockchain platform. First, we analyze the characteristics of the different components in Hyperledger Fabric and show that Fabric components have different impacts on the performance of Fabric. Then, we present QiOi, component-level performance isolation technique for Hyperledger Fabric. The key idea of QiOi is to dynamically control the CPU scheduling of Fabric components to cope with the performance interference. We implement QiOi as a user-level daemon and evaluate how QiOi mitigates the performance interference of Fabric. The evaluation results demonstrate that QiOi mitigates performance degradation of Fabric by 22% and improves Fabric latency by 2.5 times without sacrificing the performance of co-located services. In addition, we show that QiOi can support different ordering services and chaincodes with negligible overhead to Fabric performance.

A method is developed to directly map nanoscale "noise-source switching" phenomena during the optoelectronic switching of phase-separated polymer nanocomposites of tetrathiafulvalene (TTF) and phenyl-C61 -butyric acid methyl ester (PCBM) molecules dispersed in a polystyrene (PS) matrix. In the method, electrical current and noise maps of the nanocomposite film are recorded using a conducting nanoprobe, enabling the mapping of a conductivity and a noise-source density. The results provide evidence for a repeated modulation in noise sources, a "noise-source switching," in each stage of a switching cycle. Interestingly, when the nanocomposite is "set" by a high bias, insulating PS-rich phases shows a drastic decrease in a noise-source density which becomes lower than that of conducting TTF-PCBM-rich phases. This can be attributed to a trap filling by charge carriers generated from a TTF (donor)-PCBM (acceptor) complex. In addition, when the film is exposed to UV, an optical switching occurs due to chemical reactions which lead to irreversible changes on the noise-source density and conductivity. The method provides a new insight on noise-source activities during the optoelectronic switching of polymer nanocomposites and thus can be a powerful tool for basic noise research and applications in organic memory devices.

Cadaverine (CV), a death-associated odor, is an important target molecule for various sensor applications, including the evaluation of food spoilage. In this study, we developed an oriented nanodisc (ND)-functionalized bioelectronic nose (ONBN), based on carbon nanotube transistors and nanodiscs embedded with an olfactory receptor produced in Escherichia coli (E. coli) for detection of CV. To fabricate ONBN devices, a trace-amine-associated receptor 13c (TAAR13c) binding to CV was produced in E. coli, purified, reconstituted into NDs, and assembled, in the desired orientation, onto a carbon- nanotube-based field-effect transistor with floating electrodes. The ONBN showed high performance in terms of sensitivity and selectivity. Moreover, the ONBN was used to measure CV in diverse real-food samples for the determination of food freshness. These results indicate ONBN devices can be utilized to evaluate the quality of food samples quantitatively, which should enable versatile practical applications such as food safety and preservative development. Moreover, the ONBN could provide a useful tool for detection of corpses, which could be practically used in disaster responses.

Lyubashevsky proposed a lattice-based digital signature scheme based on short integer solution SIS problem without using trapdoor matrices [12]. Bai and Galbraith showed that the hard problem in Lyubashevsky's scheme can be changed from SIS to SIS and learning with errors LWE [4]. Using this change, they could compress the signatures. But Bai and Galbraith's scheme had some additional rejection processes on its algorithms. These rejection processes decreased the acceptance rate of the signing algorithm. We showed mathematically that the rejection process in key generation algorithm of [4] is not necessary. Using this fact, we suggested a scheme modified from [4]'s scheme, and doubled the acceptance rate of the signing algorithm. Furthermore, our implementation results show that our scheme is two times faster than that of [4] on similar parameter settings.

An electrical noise is one of the key parameters determining the performance of modern electronic devices. However, it has been extremely difficult, if not impossible, to image localized noise sources or their activities in such devices. We report a “noise spectral imaging” strategy to map the activities of localized noise sources in graphene domains. Using this method, we could quantitatively estimate sheet resistances and noise source densities inside graphene domains, on domain boundaries and on the edge of graphene. The results show high activities of noise sources and large sheet resistance values at the domain boundary and edge of graphene. Additionally, we showed that the top layer in double-layer graphene had lower noises than single-layer graphene. This work provides valuable insights about the electrical noises of graphene. Furthermore, the capability to directly map noise sources in electronic channels can be a major breakthrough in electrical noise research in general.

We report a successful development of a floating electrode-based DNA sensor with controllable responses. Here, metallic floating electrodes were fabricated to form Schottky barriers between carbon nanotubes and the floating electrodes. We showed that the sensor response could be enhanced by increasing the number of floating electrodes. We also analyzed the response of the sensors based on the Langmuir isotherm theory.

The aim of this study was to explore the effect of one stenosis in a daughter artery on the fractional flow reserve (FFR) of another stenosis parallels in side branch.The impact of one stenosis on the FFR of another parallel stenosis has not been evaluated.The proximal segments of the left anterior descending (LAD) and left circumflex (LCX) arteries were exposed and encircled with a Teflon pledget complex in seven swine (55-70 kg). Five degrees of stenosis (to approximate angiographic diameter stenoses of 0%, 25%, 50%, 75%, and 100%) were made by tightening the pledgets. FFR was evaluated simultaneously in the LAD and the LCX with two pressure wires in each coronary artery. A mixed-effects linear model was used to evaluate the association between the FFR values.A total of 115 paired FFR values were obtained. The FFR of the LAD and LCX were not significantly associated with each other (F = 0.237 and P = 0.627 for the LCX FFR to predict the LAD FFR; F = 0.541 and P = 0.463 for the LAD FFR to predict the LCX FFR).The individual FFR values of each parallel stenosis in the LAD and the LCX were not significantly influenced by each other. This relationship was independent of the mean aortic pressure and heart rate. © 2016 Wiley Periodicals, Inc.

We report the large-scale fabrication of high-performance field effect transistors (FETs) based on pristine semiconducting single-walled carbon nanotube (s-SWCNT) networks without bundles or organic impurities, thus exhibiting its intrinsic characteristics. Here, the solution of pristine s-SWCNTs without bundles or organic impurities was prepared in nonpolar solvent via filtration and centrifugation processes, and the s-SWCNTs in the solution were selectively assembled onto specific regions on the solid substrates via a directed assembly strategy. The fabricated FET devices based on such pristine s-SWCNT networks could exhibit a rather large on–off ratio up to over ∼106 and a subthreshold swing as small as ∼490 mV/dec, which are comparable to those of a single s-SWCNT-based device with the same device structure. Importantly, the s-SWCNT devices exhibited anomalous gating behaviors such as an on-current saturation at a large gate bias and unconventional scaling behaviors, which are quite different from tho...