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Purpose: Postsystolic shortening (PSS) and early systolic lengthening (ESL) which represent asynchrony in ischemic myocardium can provide prognostic information in patients with ST-segment elevation myocardial infarction (STEMI). We aimed to investigate the potential of PSS and ESL to detect reduced myocardial viability and investigate the comparative prognostic value of PSS and ESL in patients with STEMI after primary PCI. Methods: We prospectively enrolled 198 patients with STEMI who underwent primary percutaneous coronary intervention. All patients took a speckle tracking echocardiographic examination and myocardial contrast echocardiography a median of 3 days after the percutaneous coronary intervention. Early systolic strain index (ESI), postsystolic strain index (PSI) and myocardial perfusion score index (MPSI) were calculated. The end point was major adverse cardiovascular events (MACE), a composite of all-cause death, unstable angina, heart failure, non-fatal recurrent myocardial infarction, stroke, and complex ventricular arrhythmia. Results: Reduced myocardial viability was defined as MPSI >1. Patients with category of MPSI >1.5 increased signifcantly with increasing tertiles of PSI (1.5% vs 7.6% vs 31.8%, p 1 was 0.745 and 0.704 in ROC analysis. During a median follow-up of 9.0 months (interquartile range [IQR], 6.0-12.0 months), 39 (19.7%) patients suffered MACE. PSI and ESI remained predictors of MACE in adjusted cox regression models. In ROC analysis, IDI and NRI of PSI were significantly higher compared to GLS while ESL didn’t. Conclusion: In patients with STEMI after primary PCI, PSS and ESL provides diagnostic information on reduced myocardial viability and offers prognostic information oncardiovascular events. Additionally, PSS emerged as independent predictor of mid- and long-term MACE with superior prognostic validity compared to GLS and ESL.

Low-dimensional materials attract extensive interest in electronic applications since the synthesis of graphene. Understanding the thermal transport in low-dimensional materials with shrinking char...

3D direct planimetry is increasingly used in clinical practice as a rapid way to measure the mitral valve area (MVA) in patients with rheumatic mitral stenosis (MS) who underwent three-dimensional transesophageal echocardiography (3D-TEE). However, data on its accuracy and reliability are scarce. This study aimed to compare the MVA measurements obtained by 3D direct planimetry to the conventional technique multiplanar reconstruction (MPR) in MS patients using 3D-TEE. We retrospectively included 49 patients with rheumatic MS undergoing clinically-indicated 3D-TEE in the study. We determined the 3D direct planimetry measurements of MVA from the left atria aspect (MVALA) and the left ventricle aspect (MVALV), and compared those with the MPR method (MVAMPR). We also assessed the major and minor diameters of the mitral valve orifice using MPR and 3D direct planimetry. We found an excellent agreement between the MVA measurements obtained by the MPR method and 3D direct planimetry (MVALA and MVALV) [intraclass correlation coefficients (ICC) = 0.951 and 0.950, respectively]. However, the MVAMPR measurements were significantly larger than the MVALA and MVALV (p

Coronary microthromboembolism after acute myocardial infarction (AMI) requires urgent and effective treatment. Early and effective recovery of coronary microcirculation perfusion for the management of AMI would be crucial for better prognosis. Ultrasound assisted thrombolysis in the in-vitro experiments have great potential for the elimination of acute coronary microthromboembolism, especially with stable cavitation using low-intensity focused ultrasound (LIFU) and dodecafluoropentane-loaded acoustic phase-change nanoparticles (DDFP@NPs). Therefore, our study sought to perform animal experiments using this novel treatment method in a porcine model with acute coronary microthromboembolism for further investigation of potential therapeutic values.Porcine model with acute coronary thromboembolism was established using percutaneous coronary intervention and autologous thrombus injection. For ultrasound assisted thrombolysis, DDFP@NPs were prepared by rotary evaporation and sonication process, and LIFU was optimized. Echocardiography and TTC staining were performed for the evaluation of porcine model establishment and treatment effect.The treatment using LIFU guided DDFP@NPs had almost completely recanalized culprit coronary branch after treatment procedure, and smaller infarcted size (5.4 ± 1.0%), better LVEF (52.5 ± 1.8%) and better coronary microcirculation after 28 days of treatment, which outperformed treatments using LIFU+SonoVue microbubbles (infarcted size: 26.4 ± 3.5% and LVEF: 37.2 ± 3.1%) and LIFU only (infarcted size: 32.2 ± 3.1% and LVEF: 32.2 ± 0.4%) (all P 0.05), while the treatment effect were similar to treatment using intravenous tissue-plasminogen activator (infarcted size: 4.9 ± 0.9% and LVEF: 53.1 ± 1.1%) (all P 0.05).Our study has innovatively established a treatment method using DDFP@NPs combined with LIFU irradiation for coronary thrombolysis and verified its treatment effect with high-efficient thrombolysis in the in-vivo experiments, which can be considered as powerful experimental evident of the novel method for potential clinical use of acute coronary thrombolysis. Multidimensional experimental investigations and cautious verification may need before the method could be used as treatment before preliminary clinical trials.

In this work, we fabricate multidimensional silicon-graphene hybrid nanostructures composed of three-dimensional (3D) out-of-plane graphene flakes on a silicon nanowire core. By changing the synthesis temperature (700 and 1100 °C) and time (5, 10, and 20 min), we obtain two different types of 3D graphene flakes with tunable dimensions and structure parameters. We characterize the thermal transport behavior of this hybrid multidimensional material in a broad temperature range of 20-460 K. With different morphologies and structures, the effective thermal conductivity of the silicon-graphene hybrid nanostructures varies from 1 to 7 W/(m·K) at room temperature. We also apply molecular dynamics simulation and density functional theory to elucidate the thermal transport mechanisms in the silicon-graphene hybrid nanostructures.

The probability of toxicity-related myocardial injury event with anthracyclines is controversial, which could be related to the underlying cardiac status before chemotherapy. Our study sought to investigate the influence of cardiovascular risk factors on myocardial motion and cardiac function using layer-specific speckle tracking echocardiography (STE) during chemotherapy with epirubicin. Female patients with first-diagnosed breast cancer were prospectively enrolled in our study and received 4 chemotherapeutic cycles with epirubicin in each cycle of 21 days. All patients underwent echocardiography for layer-specific STE analysis before and after all chemotherapy. Clinical data including cardiovascular risk factors were collected. According to the Framingham score, patients with cardiovascular risk factors were divided into groups with low, medium, and high risk. 134 patients existed in the final analysis. The accumulated dose of epirubicin for were 560.0 ± 103.8 mg. 97 (72.4%) patients had cardiovascular risk factors. According to the Framingham score, 57 (42.5%) patients categorized in high risk. Endocardial layer strain after chemotherapy were lower than those at baseline (p 0.05, all), especially for patients with high risk. The changes of endocardial longitudinal strain during chemotherapy were associated with cardiovascular risks at baseline with correlation coefficient of 0.627. Our study found that layer-specific STE is valuable for early detection of toxicity-related myocardial injury for patients with breast cancer after epirubicin chemotherapy and cardiovascular risk factors have greatly influenced on cardiac function during chemotherapy. The endocardial layer strain is sensitive to evaluate early-stage toxicity-related myocardial injury after epirubicin chemotherapy.

To explore the monitoring value of left ventricular functional parameters obtained by bedside ultrasound combined with clinically relevant indicators in patients with veno-arterial extracorporeal membrane oxygenation (VA-ECMO).A retrospective study was conducted. A total of 24 patients receiving VA-ECMO adjuvant support in Renmin Hospital of Wuhan University from June 2018 to January 2020 were selected. The bedside ultrasound was performed on the first day of ECMO support, the day before weaning, the clinical indicators before weaning were obtained. The differences in clinical indicators and the left ventricular functional parameters between the two groups of whether weaning successfully were compared; univariate Logistic regression analysis was used to screen out the related factors affecting weaning.Sixteen patients were successful weaned and 8 patients failed. Compared with the weaning failure group, patients in the weaning success group required less continuous renal replacement therapy (CRRT, cases: 4 vs. 6, P0.05), mean arterial pressure (MAP) before weaning was higher [mmHg (1 mmHg = 0.133 kPa): 84.64±9.55 vs. 62.30±8.79, P0.05], and the pulse oxygen saturation (SpOBedside echocardiographic left ventricular function parameters (LVEF, LatSa, AV-Vmax, VTI, LVGLS, LVGLSr) combined with clinical indicators (MAP, VIS, SCr, Lac, SpO

Air-stable layered semiconductor Bi2O2Se has attracted extensive interest recently for applications in electronics, optoelectronics, ferroelectrics, and thermoelectrics. For many of these applications, thermal transport in Bi2O2Se is of great importance but the understanding remains elusive. Here, we perform a combined experimental and theoretical study on the anisotropic thermal conductivity of single-crystalline Bi2O2Se in comparison with its parent compound Bi2Se3 over the temperature range of 80-300 K using the time-domain thermoreflectance measurements and ab initio phonon Boltzmann transport calculations. Compared with Bi2Se3, Bi2O2Se exhibits relatively higher thermal conductivity along the through-plane direction but it is lower along the in-plane direction, resulting in substantially smaller thermal anisotropy. We find the smaller thermal anisotropy of Bi2O2Se mainly originates from its stronger interlayer electrostatic interaction compared to the typical van der Waals coupling in layered materials, which makes the phonon isoenergy surfaces less anisotropic and thus weakens phonon focusing along the in-plane directions. Our study advances the fundamental understanding of thermal anisotropy in layered materials with various interlayer interactions and will facilitate the applications of Bi2O2Se in electronics and thermoelectrics.

3D direct planimetry is increasingly used in clinical practice as a rapid way to measure the mitral valve area (MVA) in patients with rheumatic mitral stenosis (MS) who underwent three-dimensional transesophageal echocardiography (3D-TEE). However, data on its accuracy and reliability are scarce. This study aimed to compare the MVA measurements obtained by 3D direct planimetry to the conventional technique multiplanar reconstruction (MPR) in MS patients using 3D-TEE. We retrospectively included 49 patients with rheumatic MS undergoing clinically-indicated 3D-TEE in the study. We determined the 3D direct planimetry measurements of MVA from the left atria aspect (MVA

Using the principle of SR-DCSK scheme and applying code index modulation to information bearing signal, this paper presents a differential shift keying scheme with Short Reference Code Index, and applies it to space laser communication system, improving the security performance of space laser communication system.

In this paper, short reference code index differential chaotic shift keying can enhance the security performance of the system in the space laser communication system. Through the transmission of picture information, the confidentiality of the system is analyzed. The pixel correlation analysis, statistical histogram, and plaintext sensitivity prove that the system has high security performance.

The traditional drive response synchronization control method has the poor robustness, which results in the low security performance of the optical chaotic secure communication. To address this problem, an optical chaotic secure algorithm based on space laser communication is proposed in this paper. With the advantage of space laser communication and full consideration of the influence of complex environment on signal transmission of laser wireless communication, a laser wireless communication channel model is built. Based on this, a hybrid self-synchronization chaotic system model is proposed. It can reduce the information needed for transmission, and only need to transmit a small amount of error correction signals on the channel to achieve synchronization of the receiving and the transmitting system, which greatly suppress the drawback of the traditional method. On the basis of chaotic synchronization, the erbium-doped fiber laser is used for information transmission. Different encryption techniques are used to achieve optical chaotic secure communication within the allowable range of error. Numerical simulation results show that the proposed algorithm has good security and robustness, and can realize the secure communication for different signals.

After the onset of myocardial infarction, extensive coronary thrombus and oxygen supply insufficiency lead to severe myocardial damage and heart failure. Recently, ultrasound-irradiated phase-change nanoparticles have been recognized for their cardiovascular thrombolysis potential. Therefore, we sought to establish a novel treatment method using hydrogen peroxide (H

Summary The air-stable layered semiconductor Bi2O2Se has recently attracted extensive interest because of its potential application in electronics, optoelectronics, ferroelectrics, and thermoelectrics. For many of these applications, thermal transport in Bi2O2Se is of great importance, but a complete understanding of the process remains elusive. Here, we perform a combined experimental and theoretical study of the anisotropic thermal conductivity of single-crystalline Bi2O2Se in comparison with Bi2Se3. Bi2O2Se exhibits relatively higher through-plane thermal conductivity but lower in-plane thermal conductivity, resulting in substantially smaller thermal anisotropy. This behavior originates from the stronger interlayer electrostatic interaction in Bi2O2Se compared with the typical van der Waals coupling in layered materials, making the phonon isoenergy surfaces less anisotropic and, thus, weakening phonon focusing in the in-plane directions. Our study advances the fundamental understanding of thermal anisotropy in layered materials with various interlayer interactions and will facilitate application of Bi2O2Se in electronics and thermoelectrics.

Understanding the thermal transport in different Si-based materials is of both practical and academic importance because of the essential role of such materials in modern electronic and microelectromechanical applications and other areas. Conventional atomic modeling approaches such as density functional theory offer high accuracy but can hardly handle a large system, whereas the empirical potentials used in classical molecular dynamics often lack accuracy or transferability. We have thus developed a new parametrization of the Si–Si interaction of the density-functional-based tight-binding method for the atomic-scale investigation of thermal transport properties in various Si systems. We found that this parametrization can accurately predict many harmonic and anharmonic thermal transport properties in different silicon systems such as single-crystalline silicon, silicene, and silicene nanoribbons, showing excellent computational efficiency and transferability. Therefore, this Si–Si parameter set can contr...

A facile synthesis of benzo[h]quinolines has been developed via improved Combes reaction. A combination of silica gel, p-toluenesulfonic acid and phosphorus pentoxide was utilized to promote the condensation of 1-naphthylamines with 1,3-diketones under solvent free conditions. In this case, silica gel was used as reaction media, p-toluenesulfonic acid and phosphorus pentoxide were acted as catalyst and dehydrating agent, respectively.

Fundamental understanding of thermal transport properties in ultrathin Si-based films is essential for the thermal management of nanoelectronic and nanophotonic devices. Using Density-Functional-based tight-binding method and direct iterative solution of linearized Boltzmann transport equation without empirical assumptions, we systematically investigated mode-wise in-plane phonon transport in ultrathin Si films of a few nanometer thickness (0.77–1.90 nm) and the effects of surface morphology. The dimensionality reduction of these films leads to quantum confinement and softening of silicon bonds and in turn changes the dispersion and phonon-phonon interactions. The ultrathin Si films with naturally reconstructed surfaces show a counterintuitively high in-plane thermal conductivity (∼30 W/m-K at 300 K) with relatively weak size dependence and large acoustic phonon contribution, demonstrating that dimensionality reduction alone cannot suppress phonon transport in ultrathin films efficiently. The in-plane thermal conductivities of ultrathin films are very sensitive to surface defects and even atomic-level surface defects can induce up to 10-fold reduction in thermal conductivity due to much enhanced phonon scatterings in low frequency regime. Our direct first-principle-based calculations also show that the conventional modeling of thin films with bulk properties and suppression function may lead to large uncertainty when applied to ultrathin films.

It is generally understood that particle-shaped Li2O2 is preferred in Li-O2 batteries (LOBs) because the dominance of Li2O2 films may lead to poor electrochemical performance. The influence of Li2O2 morphology and its nucleation mechanism are probed by experiments along with the first-principle calculations. It is revealed that the LOBs with Li2O2 films deliver unexpectedly improved capacities, longer cycles, and significantly reduced overpotentials assisted by NiFeOx nanofiber catalysts. The energetically favored Li 2a vacancies under LiO2-rich conditions, small crystallites, and large contact areas with the electrode/electrolyte explain the anomalous performance enhancement. Li2O2 films are formed by a heterogeneous nucleation mechanism and the voltage applied, electrolyte, electrode surface, and use of catalysts are identified as the parameters controlling the mechanisms. The mapped correlations among these parameters shed light on the control of Li2O2 morphology for developing high-performance LOBs.

We report that single interatomic potential, developed using Gaussian regression of density functional theory calculation data, has high accuracy and flexibility to describe phonon transport with ab initio accuracy in two different atomistic configurations: perfect crystalline Si and crystalline Si with vacancies. The high accuracy of second- and third-order force constants from the Gaussian approximation potential (GAP) are demonstrated with phonon dispersion, Gr\"uneisen parameter, three-phonon scattering rate, phonon-vacancy scattering rate, and thermal conductivity, all of which are very close to the results from density functional theory calculation. We also show that the widely used empirical potentials (Stillinger-Weber and Tersoff) produce much larger errors compared to the GAP. The computational cost of GAP is higher than the two empirical potentials, but five orders of magnitude lower than the density functional theory calculation. Our work shows that GAP can provide a new opportunity for studying phonon transport in partially disordered crystalline phases with the high predictive power of ab initio calculation but at a feasible computational cost., Comment: 17 pages, 5 figures

Point defects in solids such as vacancy and dopants often cause large thermal resistance. Because the lattice site occupied by a point defect has a much smaller size than phonon wavelengths, the scattering of thermal acoustic phonons by point defects in solids has been widely assumed to be the Rayleigh scattering type. In contrast to this conventional perception, using an ab initio Green's function approach, we show that the scattering by point defects in PbTe and GeTe exhibits Mie scattering characterized by a weaker frequency dependence of the scattering rates and highly asymmetric scattering phase functions. These unusual behaviors occur because the strain field induced by a point defect can extend for a long distance much larger than the lattice spacing. Because of the asymmetric scattering phase functions, the widely used relaxation time approximation fails with an error of ~20% at 300K in predicting lattice thermal conductivity when the vacancy fraction is 1%. Our results show that the phonon scattering by point defects in IV-VI semiconductors cannot be described by the simple kinetic theory combined with Rayleigh scattering., 31 pages, 14 figures

van der Waals (vdW) heterostructures are a central focus of materials science and condensed matter physics due to the novel physical phenomena and properties obtained by precisely stacking heterogeneous atomically thin layers. vdW heterostructures are expected to allow for the coherent manipulation of THz lattice vibrations and hence heat conduction due to the ability to precisely control chemical composition at the atomic scale, but little work has focused on thermal transport in these materials. Here, we report an ab initio study of thermal transport in vdW superlattices consisting of alternating transition metal dichalcogenide atomic layers. Our calculations show that the lattice vibrational spectrum and scattering rates can be precisely manipulated by the choice of each atomically thin layer, resulting in materials with novel properties such as large thermal anisotropies approaching 200 and ultralow cross-plane thermal conductivities comparable to those of amorphous materials. Our work demonstrates how coherent manipulation of phonons in vdW superlattices can expand the property space beyond that occupied by natural materials and suggests an experimental route to realize these properties.

This paper proposes an information system framework for production collaboration and standardization in Chinese liquor industry, and examines the key implementation issues of information systems in Chinese liquor production. A descriptive single case study is conducted to explore and identify the benefits, challenges, and success factors of information system implementation in Chinese liquor production by taking a famous Chinese liquor producer as the target case company. The case study shows that the proposed information system framework is helpful to improve collaboration and standardization in Chinese liquor production. Some benefits and challenges of implementing information systems are different from those described in previous studies because of various distinct, real-world features of Chinese liquor production. The proposed system framework offers the possibility to improve the Chinese liquor producer's production efficiency and market competition by better production collaboration and standardization.

The thermal transport properties of metal–organic frameworks (MOFs) developed for molecular storage and catalytic separations play an important role in adsorption or catalysis processes but are rarely reported. We calculate the anisotropic thermal conductivities (κ) of water-stable Zn-MOF-74 with the Boltzmann transport equation and the density-functional-based tight-binding (DFTB) method, which allows for a sufficiently large number of atoms in the simulations without much compromise on accuracy. We find an anisotropic κ of 0.44 and 0.68 W/m·K at 300 K, across and along the pore directions, with acoustic contributions of 8% and 30%, respectively. These unusually low acoustic contributions are explained by the rattling-like behavior of phonons with large vibrational amplitude, low group velocity, and large scattering rate, which are caused by the unique 1-D tubing bundle structure. On the other hand, the cylindrical pores enable larger phonon speed and higher directional structural rigidity along the pore...

An inexpensive silica sulfuric acid (SSA) mediated acylation of amines with 1,3-diketones via C C bond cleavage was realized under solvent and transient metal free conditions. In this chemistry, both catalytic aerobic oxidative and hydrolyzed C C bond cleavage were coexisted. Furthermore, the activation of molecular oxygen by non-transient metal catalyst (SSA) was disclosed.