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BACKGROUND: Visualization of diffuse myocardial fibrosis is challenging and mainly relies on histology. Cardiac magnetic resonance (CMR), which uses extracellular contrast agents, is a rapidly developing technique for measuring the extracellular volume (ECV). The objective of this study was to evaluate the feasibility of the synthetic myocardial ECV fraction based on 3.0 T CMR compared with the conventional ECV fraction. METHODS: This study was approved by the local animal care and ethics committee. Fifteen beagle models with diffuse myocardial fibrosis, including 12 experimental and three control subjects, were generated by injecting doxorubicin 30 mg/m(2) intravenously every three weeks for 24 weeks. Short-axis (SAX) and 4-chamber long-axis (LAX) T1 maps were acquired for both groups. The association between hematocrit (Hct) and native T1(blood) was derived from 9 non-contrast CMR T1 maps of 3 control beagles using regression analysis. Synthetic ECV was then calculated using the synthetic Hct and compared with conventional ECV at baseline and the 16(th) and 24(th) week after doxorubicin administration. The collagen volume fraction (CVF) value was measured on digital biopsy samples. Bland-Altman plots were used to analyze the agreement between conventional and synthetic ECV. Correlation analyses were performed to explore the association among conventional ECV, synthetic ECV, CVF, and left ventricular ejection fraction (LVEF). RESULTS: The regression model synthetic Hct = 816.46*R1(blood) − 0.01 (R(2)=0.617; P=0.012) was used to predict the Hct from native T1(blood) values. The conventional and synthetic ECV fractions of experimental animals at the 16(th) and 24(th) week after modeling were significantly higher than those measured at the baseline (31.4%±2.2% and 36.3%±2.1% vs. 22.9%±1.7%; 29.9%±2.4% and 36.1%±2.6% vs. 22.0%±2.4%; all with P

The effect of environmental uncertainty on equilibrium patterns is of vital importance to understand travel choice behavior. This paper conducted a laboratory experiment to investigate the effects of stochastic bottleneck capacity on departure time choice behavior. In the experiment, the bottleneck capacity varied stochastically from round to round, and two different scenarios with different information feedback were investigated. Our experimental results showed that the relationship between the mean travel cost and the standard deviation of travel cost on each departure time was fitted approximately linearly with a positive slope λ∗, indicating subjects were more likely to minimize their travel cost budget rather than their mean travel cost. Also, we found that the feedback on costs of all departure times resulted in a smaller λ∗ than the feedback on the subjects’ own travel cost only. We propose a reinforcement learning model to reproduce the main experimental findings.

Whether uptake of rainwater can increase plant water consumption in response to rainfall pulses requires investigation to evaluate the plant adaptability, especially in water limited regions where rainwater is the only replenishable soil water source. In this study, the water sources from rainwater and three soil layers, predawn (Ψpd), midday (Ψm) and gradient (Ψpd−Ψm) of leaf water potential, and water consumption in response to rainfall pulses were analyzed for two dominant tree species, Hippophae rhamnoides and Populus davidiana, in pure and mixed plantations during the growing period (June–September). In pure plantations, the relative response of daily normalized sap flow (SFR) was significantly affected by rainwater uptake proportion (RUP) and Ψpd−Ψm for H. rhamnoides, and was only significantly influenced by Ψpd−Ψm for P. davidiana (P pd−Ψm was consistent with high SFR for H. rhamnoides, and the small Ψpd−Ψm was consistent with the low SFR for P. davidiana, in response to rainfall pulses. Therefore, H. rhamnoides and P. davidiana exhibited sensitive and insensitive responses to rainfall pulses, respectively. Furthermore, mixed afforestation significantly enhanced RUP, SFR, and reduced the water source proportion from the deep soil layer (100–200 cm) for both species (P R was significantly influenced by RUP and Ψpd−Ψm for both species in the mixed plantation. Lower Ψm and higher Ψpd were adopted by H. rhamnoides and P. davidiana in mixed plantation, respectively, to enlarge Ψpd−Ψm, enhance rainwater uptake, and decrease water source competition from the deep soil layer. These results indicate that mixed afforestation enhanced the influence of rainwater uptake to water consumption after rainfall pulse, regardless of sensitivity to rainfall pulses. This study provides insights into suitable plantation species selection and management considering the link between rainwater uptake and consumption in water limited regions.

METTL3 encodes the predominant catalytic enzyme to promote m

Based on the delayed self-heterodyne scheme, the linewidths of DFB and ECL are measured and analyzed by PSD of optical field, variance of phase difference and FM-noise PSD spectrum. The latter can measure the linewidth produced by white FM-noise. The impact of white noise and flick noise of laser on BER and mismatch length is researched.

We propose a joint phase noise compensation scheme including SP-LMS and RPD-BPS algorithm in the optical carrier-assisted SSB-DD PAM4 system with high spectral efficiency, which can tolerate 1-MHz laser linewidth at a BER of 3.8e-3.

A Kalman filter-based Auto Bias Controller (KF-ABC) is proposed for IQ modulator. Compared with traditional ABC techniques, KF-ABC can achieve a significant improvement in convergence speed and accuracy.

In this paper we experimentally investigate the performance of 448 Gb/s PS-PDM-PAM8 coherent transmission over multi-core fiber. 22.4 Gb/s improvement in net bit rate can be achieved by using PS-PDM-PAM8 compared with U-PDM-PAM4.

Recently, high-speed optical transmission using single-side-band (SSB) modulation with Kramers-Kronig (KK) scheme has gained great attention due to its high spectral efficiency (SE) and capability of electronic chromatic dispersion compensation (CDC), which can be widely employed in optical metro networks as a promising transmission scheme. To our knowledge, the carrier-signal power ratio (CSPR) is the key parameter to SSB-based systems and the optimum CSPRs can vary distinctly in different SSB modulation schemes. In this paper, the SSB-based KK systems with four kinds of SSB signal generation schemes are investigated, i.e. optical carrier-assisted SSB (OCA-SSB), virtual carrier-assisted SSB (VCA-SSB), SSB subcarrier modulation (SSB SCM) with IQ modulator (IQM) and with dual-drive Mach-Zehnder modulator (DDMZM) respectively. Here, the detailed theoretical derivations of these modulation processing are given and the theoretical relationship between device parameters and the CSPR has been further studied for the different SSB schemes. In order to verify those theoretical analyses, a 224-Gb/s direct detection (DD) transmission with SSB 16-ary quadrature amplitude modulation (16-QAM) signal has been demonstrated based on four SSB generation methods. The results show that theoretical derivations are closely consist with numerical analysis, such as $V_{bias}$ in the scheme of SSB SCM with IQM and optical modulation index (OMI) in SSB SCM with DDMZM. Therefore, our research can provide a theoretical guidance of appropriate device parameter configuration so as to achieve the optimum performance for SSB systems.

Emulsification using phase inversion composition (PIC) was achieved by changing the composition of surfactants at a constant temperature. The method has great potential to scale up applications due to the ease in the formation of nanoemulsions and the relatively low energy involved. Surfactants containing composition-sensitive polyoxyethylene (POE) chains are widely used to prepare nanoemulsions using the PIC method. It is, therefore, anticipated that surfactants containing composition-sensitive polyoxypropylene (POP) chains can also be used to prepare nanoemulsions using the PIC method. The POP surfactant D230-2OA, containing short POP chains, was obtained from the electrostatic interactions between hydrophilic POP diamine (D230) and hydrophobic oleic acid (OA). The synthesized D230-2OA was used as an emulsifier in the preparation of the n-dodecane-in-water nanoemulsion using the PIC method. The effects of D230-2OA concentration, oil-to-surfactant weight ratio, and NaCl concentration on the droplet size of the nanoemulsions was investigated using dynamic light scattering (DLS). The morphology of the nanoemulsion was characterized using cryogenic transmission electron microscopy (cryo-TEM). The wettability of the crude oil–saturated quartz plate before and after treatment with nanoemulsions was obtained using contact angle measurement. A core flooding experiment demonstrated the efficiency of the diluted nanoemulsion in enhanced oil recovery, with an additional recovery of 21.30%. The nanoemulsion prepared with the POP surfactant as the emulsifier using the PIC method has wide application in petroleum recovery.

A pre-configured Kramers-Kronig (Pre-KK) scheme is proposed for single sideband (SSB) systems and demonstrated that a better performance can be achieved than traditional KK scheme because of reducing the requirement of DAC and ADC resolution.

One important feature of the transportation system is uncertainty. Based on Vickrey’s bottleneck model, we conducted a laboratory experiment to study commute problem with stochastic capacity. The experimental results show that, for either player or departure time, the mean cost and the standard deviation of cost differ significantly, and the relationship between mean cost and standard deviation of cost can be approximately fitted linearly with a positive slope. Our experiment demonstrates that in the uncertain condition, the players seem to minimize their cost budget and they behave risk preference.

In this paper, an asynchronous single channel sampling (ASCS) based joint modulation format and baud rate identification (MF–BRI) method is proposed for M-QAM optical systems using Convolutional Neural Network (CNN), which significantly reduces the cost and complexity of monitoring system setup. Based on the three influencing factors of OSNR, CD and DGD, three sampling rates are analyzed to generate ASCS images to build the database. The simulation and experiment accuracy of MFI and MF–BRI is above 99.8%. We also discuss the differences between two-channel sampling (TCS) and single-channel sampling (SCS).

PURPOSE To investigate the diagnostic accuracy of coronary computed tomographic (CT) angiography (CCTA) using filtered back projection (FBP) and sinogram-affirmed iterative reconstruction (SAFIRE) of different strength factors with invasive coronary angiography as the reference standard. MATERIALS AND METHODS Fifty consecutive patients (32 men and 18 women) prospectively underwent electrocardiogram-triggered CCTA on a dual-source CT system. The acquisition window was set depending on the heart rate (HR): HR of less than 60 beats per minute (bpm) at the 70% RR interval, 61 to 80 bpm at 30% to 80% RR interval, and greater than 80 bpm at 30% to 50% RR interval; 100 kV and 359 to 377 mA s for patients with a body mass index of less than 24 kg/m, and 410 to 438 mA s at 120 kV for patients with a body mass index of 24 kg/m or greater. Image data were reconstructed using both FBP and SAFIRE. Sinogram-affirmed iterative reconstruction series were reconstructed using 3 different strength factors. Two blinded observers independently assessed the image quality and image impression of each coronary segment using a 4-point scale (1, non-diagnostic; and 4, excellent). Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured. Filtered back projection and all SAFIRE series were independently evaluated for coronary artery stenosis (>50%), and their diagnostic accuracy was compared with invasive coronary angiography. RESULTS Statistically significant increases in SNR and CNR were obtained when higher strength factors were used. The highest SNR and CNR were found with the highest SAFIRE strength factor of 5; however, this strength also resulted in a more unfamiliar, "plasticlike" image appearance. Imaging quality scores of FBP and different SAFIRE strengths were 3.37 ± 0.49, 3.41 ± 0.47, 3.52 ± 0.30, and 3.48 ± 0.35, respectively (P < 0.001). The diagnostic accuracies were 92.91%, 93.76%, 95.28%, and 94.94% on per-segment level, respectively (P = 0.993). A tendency toward higher diagnostic performance was observed with SAFIRE strength factor 3 on per-segment analysis, albeit without reaching statistical significance. The effective radiation dose equivalent was 5.7 ± 1.6 mSv. CONCLUSION Sinogram-affirmed iterative reconstruction provides significant improvements in image noise, SNR, and CNR compared with FBP, which are progressive with increasing SAFIRE strength factors. Sinogram-affirmed iterative reconstruction strength factor 3 or 5 is recommended for use with CCTA.

We realize the identification of commonly-used modulation formats including 4QAM, 16QAM and 64QAM by using the principal component analysis (PCA) and asynchronous delay-tap sampling (ADTS).

The purpose of this study is to investigate whether an iterative reconstruction in image space (IRIS) algorithm improves the image quality of dual-energy CT abdominal examinations performed during the hepatic arterial phase.Seventy patients with suspected liver masses underwent contrast-enhanced multiphase abdominal examination and were enrolled in the study. A dual-energy CT protocol was performed in the hepatic arterial phase (parameters: tube A, 140 kV and 90 mA; tube B, 80 kV and 382 mA; automatic tube current modulation on; and collimation, 14 × 1.2 mm). The reconstructions were performed with filtered back projection (FBP) and IRIS algorithms at a slice thickness of 3 mm and kernels of B30 and I30. The image noise was measured on the liver, aorta, and subcutaneous fat on the FBP and IRIS fusion images (m = 0.3) at the same position. The image noise and diagnostic acceptability of all images were scored by two radiologists.The image noise using the IRIS algorithm was lower than that using the standard FBP algorithm on the liver, aorta, and subcutaneous fat, respectively. The signal-to-noise ratio and contrast-to-noise ratio of images reconstructed with the IRIS algorithm also were significantly higher than for those reconstructed with the FBP algorithm. The diagnostic acceptability score using the IRIS algorithm was higher than that using the FBP algorithm at the same dose level (1.20 ± 0.40 vs 1.37 ± 0.57; p0.05).Compared with standard FBP reconstruction, an IRIS algorithm enables significant reduction of image noise and improvement of image quality and has the potential to decrease radiation exposure during contrast-enhanced dual-energy CT abdominal examination.

Based on the fact about self-regions in current power system, a new topology regions method is firstly proposed. Then a new comprehensive risk assessment method on electrical substation for dispatching operation is presented, in which the risk of bus system arrangement and equipment operation state within a substation and the overall topology of a substation during a whole power system are all considered. Finally, the correctness and effectiveness of this method are tested by the utilization in a real power system.

This paper presents a new risk assessment method for cascading failure caused by electric cyber-physical system (ECPS). The development of a trustworthy smart grid requires a deeper and more specific analysis of potential impacts resulting from failures of ECPS. A probability model is presented to calculate the reliability of ECPS which controls the security and stability control system. Cascading failure due to failures of ECPS is being investigated by risk assessment method in this paper. Two scenes including signal lost and signal transmission error which may lead to cascading failure in power system is considered. IEEE 118-bus system is used as a test system and the simulation results verifies the effectiveness of proposed failure model and risk assessment method.

Traditional risk assessment methods focus on the power network side while ignoring the impacts of the information system. A risk assessment approach for power system based on a comprehensive fault probabilistic model is proposed. The risk factors of the information system are considered in the model. Overload and voltage violation risk indices are adopted. The risk indices thus gained can be used to help operators and the planners to monitor the system, and make a more credible plan. The correctness of the proposed approach is validated by IEEE-118 bus test system.

In the power system, there probably exist some certain risks during the dispatching operation when it is determined by a fallacious recognition of system conditions. A risk assessment approach for dispatching operations is proposed. The risk of dispatching operations is defined as the overload or voltage violation induced after operations. A critical equipment search technique used for contingency searching is developed to enhance computational efficiency. The risk indices thus gained can be used to monitor the dispatching operations, and help operators to determine more credible operations or daily operation plan. The correctness and effectiveness of the proposed approach are validated by IEEE-118 bus test system and the Polish power system.

To determine whether prospective electrocardiogram (ECG)-gated delayed contrast-enhanced dual-source computed tomography (DCE-DSCT) can accurately delineate the extension of myocardial infarction (MI) compared with delayed enhanced cardiac MR (DE-MR).Eleven patients were examined using dual-source CT and cardiac MR in 2 weeks after a first reperfused MI. DCE-DSCT scan protocol was performed with prospective ECG-gating sequential scan model 7 min after contrast administration. In a 17-model, infarcted myocardium detected by DE-MR was categorized as transmural and subendocardial extension. Segment of infarcted location and graded transmurality were compared between DCE-MDCT and DE-MR.In all eleven patients, diagnostic quality was obtained for depicting delayed enhanced myocardium. Agreement between DCE-DSCT and MR was good on myocardial segment based comparison (kappa=0.85, p0.001), and on transmural and subendocardial infarction type comparison (kappa=0.82, p0.001, kappa=0.52, p0.001, respectively). CT value was higher on infarcted region than that of normal region (100.02±9.57 HU vs. 72.63±7.32 HU, p0.001). Radiation dose of prospectively ECG-gating protocol were 0.99±0.08 mSv (0.82-1.19 mSv).Prospective ECG-gated DCE-DSCT can accurately assess the extension and the patterns of myocardial infarction with low radiation dose.