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Crotonyanes A (1) and B (2), two new cembranoids were isolated from the leaves and twigs of Croton yanhuii Y. T. Chang. Their structures were elucidated by extensive spectroscopic analyses and quantum chemical calculations. Bioassays verified that compound 1 exhibited an inhibitory effect on nitric oxide (NO) production in RAW 264.7 cells, with an IC50 value of 30.6 ± 4.3 µM.

Mass transfer stability is an essential issue in binary evolution. Ge et al. studied critical mass ratios for dynamically stable mass transfer by establishing adiabatic mass loss model and found that the donor stars on the giant branches tend to be more stable than that based on the composite polytropic stellar model. We would investigate the influence of mass transfer stability on the formation and properties of DWD populations. We performed a series of binary population synthesis, where the critical mass ratios from adiabatic mass loss model (Ge's model) and that from the composite polytropic model are adopted, respectively. For Ge's model, most of the DWDs are produced from the stable non-conservative Roche lobe overflow plus common envelope (CE) ejection channel (RL+CE channel) regardless of the CE ejection efficiency $\alpha_{CE}$. While the results of the polytropic model strongly depend on the adopted value of $\alpha_{ CE}$. We find DWDs produced from the RL+CE channel have comparable WD masses and the mass ratio distribution peaks at around 1. Based on the magnitude-limited sample of DWDs, the space densities for the detectable DWDs and those with extremely low-mass WD (ELM WD) companions in Ge's model is $1347$ and $473 kpc^{-3}$, respectively, close to observations. While the polytropic model overpredicts space density of DWDs by a factor of about $2-3$. We also find that the results of DWD merger rate distribution in Ge's model reproduce the observations better than that of the polytropic model, and the merger rate of DWDs with ELM WD companions in the Galaxy is about $1.8\times 10^{-3} yr^{-1}$ in Ge's model, which is comparable to the observation estimation. We confirm that the mass transfer stability plays important roles in the formation and properties of DWD populations, and then in the progenitors of SNe Ia and detectable GW sources., Comment: 28 pages, 17 figures; A&A version

BackgroundIt has been reported that sacubitril/valsartan can improve cardiac function in acute myocardial infarction (AMI) patients complicated by heart failure (HF). However, a number of patients cannot be treated successfully; this phenomenon is called sacubitril/valsartan resistance (SVR), and the mechanisms remain unclear.MethodsIn our present research, the expression profiles of transfer RNA (tRNA)-derived small RNAs (tsRNAs) in SVR along with no sacubitril/valsartan resistance (NSVR) patients were determined by RNA sequencing. Through bioinformatics, quantitative real-time PCR (qRT-PCR), and cell-based experiments, we identified SVR-related tsRNAs and confirmed their diagnostic value, predicted their targeted genes, and explored the enriched signal pathways as well as regulatory roles of tsRNAs in SVR.ResultsOur research indicated that 36 tsRNAs were upregulated and that 21 tsRNAs were downregulated in SVR. Among these tsRNAs, the expression of tRF-59:76-Tyr-GTA-2-M3 and tRF-60:76-Val-AAC-1-M5 was upregulated, while the expression of tRF-1:29-Gly-GCC-1 was downregulated in the group of SVR. Receiver operating characteristic (ROC) curve analysis demonstrated that these three tsRNAs were potential biomarkers of the therapeutic heterogeneity of sacubitril/valsartan. Moreover, tRF-60:76-Val-AAC-1-M5 might target Tnfrsf10b and Bcl2l1 to influence the observed therapeutic heterogeneity through the lipid and atherosclerosis signaling pathways.ConclusionHence, tsRNA might play a vital role in SVR. These discoveries provide new insights for the mechanistic investigation of responsiveness to sacubitril/valsartan.

The novel high hydrophobic graphene/vinyl-functionalized SiO2 composites were prepared via self-assembly of graphene sheets on the surface of vinyl-functionalized silica (VF-SiO2) nanoparticles. Th...

When 5G slice network is applied to bear intelligent substation monitoring, one can obtain qualified service quality and reduce the slice rental cost, though reasonable and customized virtual network resources allocation among time-sensitive, mobile broadband, and narrow-band sensing services. As a result, the mapping model of electrical service demand onto communication and computing resources of network slices was established, and the mechanism and transformation between them are revealed. Constrained by the transmission bandwidth, time delay and computing resource demand of the electrical multiple services, the economical efficiency optimization problem of electric 5G multi-service network slice is formulated. A joint allocation algorithm of communication and computing resources is proposed to address the issue of efficient and economic resources utilization.

Zejuan Ji,1 Keming Sun,1 Zhenwei Li,1 Weyland Cheng,1,2 Junwen Yang3 1Department of Orthopaedic Surgery, Children’s Hospital Affiliated to Zhengzhou University, Henan Children’s Hospital, Zhengzhou Children’s Hospital, Zhengzhou, Henan, People’s Republic of China; 2Henan Provincial Key Laboratory of Children’s Genetics and Metabolic Diseases, Children’s Hospital Affiliated to Zhengzhou University, Henan Children’s Hospital, Zhengzhou Children’s Hospital, Zhengzhou, Henan, People’s Republic of China; 3Microbiology Laboratory, Children’s Hospital Affiliated to Zhengzhou University, Henan Children’s Hospital, Zhengzhou Children’s Hospital, Zhengzhou, Henan, People’s Republic of ChinaCorrespondence: Zejuan Ji; Weyland Cheng Tel +86 18538557605; +86 18502758200Email Jizejuan_Cristina@126.com; wey_c@hotmail.comAbstract: Increasing cases of carbapenem-resistant Klebsiella pneumoniae (CR-KP) infections have been observed globally where multi-drug resistance to CR-KP can make the infection difficult to treat. In recent years, the β-lactam/β-lactamase inhibitor, ceftazidime-avibactam (CAZ-AVI), has been developed to treat complicated urinary tract infections and complicated intra-abdominal infections. CAZ-AVI is approved for children over 3-month old but has yet to be investigated for cases of osteomyelitis. Only three case reports exist in literature on the use of CAZ-AVI for CR-KP osteomyelitis in adults. In this report, we present an infant with primary hematogenous osteomyelitis and septic arthritis in the right shoulder following surgical treatment for a heart murmur. Bacterial isolation revealed a strain of CR-KP, which was successfully treated with CAZ-AVI after initial administration of imipenem-based treatments.Keywords: carbapenem-resistant Enterobacteriaceae, multi-drug resistant, β-lactam/β-lactamase inhibitor, antibiotic, susceptibility test

Self-healing microcapsules were filled with a glue-like chemical that can repair damage and recover the original functions of materials. Graphene oxide (GO) was employed as the stabilizer of Pickering emulsions, and then the microcapsule shells were built upon the self-assembly of GO at oil/water interfaces. Linseed oil was encapsulated in the microcapsules as the healing agent. Several important factors were studied that affected the stabilization of the Pickering emulsions and the formation of the integral microcapsules, such as the pH value of GO aqueous solution, the GO/linseed oil mass ratio and the effect of surfactant. Chemical stitching of GO sheets by polyetheramine molecules were employed to enhance the chemical stability of the microcapsules. The waterborne polyurethane (PU) composite coatings containing 10 wt% microcapsules autonomously healed a scratch with 20 μm in width. After healing, the impedance modulus of the composite coatings was four orders of magnitude higher than neat PU.

The estimation of point spread function of remote sensing images is the necessary premise to improve the quality and to reduce the optical blur. The oblique straight edge method is greatly limited by the target. Though existing curve edge methods overcome the drawback that the oblique edge methods can only be applied to the straight edges, but will result in large estimation value error because of the stretching coordinate. An curve edge method of arbitrary shape based on the edge method of projection is proposed using the idea of moving windows. And the feasibility is explained theoretically. In the process of experimental verification, the proposed method first fits the edge points linearly, then uses the projection method to sample the gray values of the rows or columns in a selected window and aligned the sampling centers of different windows, finally estimates the point spread function using interpolation and resampling after eliminating the improper sampling points. For the edges with curvatures from 0.001 to 0.01, the peak signal-to-noise ratio can still stay above 35 dB even though under strong blur. The error of peak of the point spread function can be controlled within 20%. Compared with the traditional edge method and curve fitting method, our method has better results for all kinds of curves that the average peak signal-to-noise ratio can be improved by more than 10 dB, and has somewhat anti-noise performance.

Graphene derivatives can function as a barrier reinforcement in waterborne epoxy (WEP) coatings. The main challenge lies in the demulsification of epoxy emulsions caused by the addition of graphene derivatives and the dispersion of graphene sheets with a relatively high filler content. Herein, sulfonic acid groups were grafted on the edges of graphene sheets. The sulfonated graphene (SG) can be stably dispersed in water and waterborne epoxy emulsions, while graphene oxide (GO) caused demulsification of epoxy emulsions. Assembly of SG sheets at oil/water interfaces in WEP emulsions was proposed, which co-stabilized the WEP emulsions. SG reinforced WEP coatings were fabricated on carbon steel plates for corrosion protection. When the SG content was 0.2 wt%, SG sheets were nanoscopically well dispersed in WEP coatings. With the increase of the SG content, the SG sheets tended to assemble parallelly in short ranges, leaving a distance of 20–30 nm between the neighboring sheets. The corrosion protection properties of the coatings were significantly improved by the dispersed SG sheets, as well as the parallelly assembled SG sheets. The most remarkable improvement was achieved by adding 1.0 wt% SG into the WEP coatings, where the impedance modulus at 0.1 Hz was 193 times higher than that of the neat WEP coatings after 150 days of immersion in electrolytes. The outstanding corrosion protection properties were attributed to the stable WEP emulsions, the physical barrier properties of SG, the high SG content, and the sufficient distance between the parallelly assembled SG.

Quantifying the relative contributions of climate and human activities to changes in sediment discharge is closely related to regional water resources, soil management and even the healthy operation of ecosystems. However, few studies used different methods to decompose influences of climatic variability and human activities on sediment discharge change, especially in karst regions of southwest China where experiencing severe soil erosion. This study systematically reviewed four different methods including simple linear regression method, double mass curve method, sediment identify factor analysis, and elastic coefficient method to separate the contribution of climate change and human activities to sediment discharge variation in four karst watersheds of southwest during 1955 to 2015. The trend and abrupt change year of sediment discharge in four watersheds were obtained by nonparametric Mann-Kendall test. Result showed that the sediment discharge in four watersheds all decreased significantly (P

In order to meet the needs of refined grid planning of medium voltage distribution network and improvement of standardization requirements, this paper proposes a prospective wiring optimization model of medium voltage distribution network considering multiple transformation scenarios. Firstly, two types of typical wiring forms of the prospective grid are quantitatively described; Secondly, three types of transformming and planning solutions are classified and modeled. Pareto optimization is used to coordinate the two optimization goals of construction cost and retention of the current grid. Finally, the validity and practicability of the model are verified through the analysis of a numerical example

Recently, with the rapid development of smart grid and the increasing demand for electricity, it is imperative to build a power consumption information collection system that can serve the normal operation of the smart grid business. Narrow-Band Internet of Things (NB-IoT) is used to support power consumption information collection system. As the spectrum bandwidth of NB-IoT is only 180 kHz, how to make resource allocation and scheduling more efficiently becomes a key issue. In this paper, we deeply analyze the uplink resource scheduling related factors for NB-IoT firstly, including resource allocation scheme, power control, and uplink transmission gap, etc. Next, the selection of modulation and coding schemes, and the number of repeated transmissions is analyzed based on different coverage levels. The greedy-stable selection modulation and coding strategy of the rate margin report are used to select the modulation and coding level, and then a compensation is adopted to determine the number of repeated transmissions. Simulation results show that compared with the direct transmission method, the solution can save more than 56% of the activity time and 46% of the resource consumption.

With the development of wireless communication network, 5G H-CRAN network has gradually become the focus of research. The increasing demands for mobile data multimedia services and high bandwidth multimedia services require the network to provide efficient multicast services in smart grid communications. The multicast effect is mainly determined by the worst users of QoS in all multicast users, which are clustered at the edge of the cell. Therefore, there is a need to find ways to enhance the user experience in the edge area. In this paper, a 5G multicast enhancement scheme based on cooperative transmission is proposed, which can effectively enlarge the coverage of the network and improve the signal quality of edge users. We model and discuss the effect of cooperative transmission enhancement through different collaboration patterns. We define the system to ensure effective throughput metrics in the process of cooperative enhancement equalization. The simulation results show that cooperative mode selection of QoS is guaranteed in different systems.

Quantum secure direct communication (QSDC) is a secure communication method that uses the quantum state as an information carrier to directly transmit the message between two remote anticipators. In the free-space quantum communication, atmospheric turbulence causes fluctuations in transmittance, which further affects the quantum bit error rate (QBER) and signal-to-noise ratio (SNR). Under such circumstances, the intensity of some optical signals arriving at the remote end may be weak, which makes it difficult to meet the requirements of secure communication. In order to solve this problem, a free-space QSDC scheme based on prefixed-threshold real-time selection (P-RTS) method is proposed. In this scheme, the sender transmits all photons in the pulse way, and the remote end receives these pulses responding to the optical threshold which is calculated by the P-RTS method. It shows that the proposed scheme has lower QBER and higher SNR than other QSDC scheme through analysis.

Sparse coding-inspired high-resolution inverse synthetic aperture radar (ISAR) imaging based on multistage compressive sensing (CS) is proposed in this paper. To achieve high cross-range resolution within a short coherent processing interval (CPI), we divide the ISAR imaging process into multiple stages, each of which can be regarded as sparse-coding processing, and the encoding and decoding matrices can be obtained by solving an optimization problem using the error backpropagation algorithm. The decoding matrix can be regarded as a sparse dictionary, and we can recover the ISAR image by exploiting the smoothed ${l_0}$ norm algorithm based on the decoding matrix and CS theory. The ISAR image is then transformed into a time-domain echo by the inverse fast Fourier transform, and the echo can be regarded as the input for the next stage. At each stage, the resolution is gradually improved until we obtain the expected high-resolution ISAR image. Thus, the signals' energy can be fully accumulated step by step, and we can obtain a less noise and focused ISAR image. Experimental results show that the proposed method can obtain higher quality ISAR images compared with other current techniques, and that it is an effective approach to ISAR imaging within a short CPI.

The corrosion behaviour and passive films formed on Ni-based single crystal superalloys with different orientations were investigated through the electrochemical testing and microstructural analysis. The results show that the corrosion rates of the different planes increases in the order of (001)

In order to achieve accurate temperature measurement in a fast temperature change environment, a set of thin film thermocouple test system for transient temperature measurement is designed and developed. The system consists of cold junction compensation and data collector. The temperature of the film thermocouple can be obtained in real time through the upper acquisition software. The hardware composition and software design of the thin film thermocouple test system are given. The data acquisition terminal and coordinator program are designed to control the temperature signal of the MAX31855 to collect the sensor, realizing the real-time transmission of temperature data between the sensor and the computer. In order to verify the actual application effect of the system, the matching, stability and reliability of the temperature acquisition system and monitoring software, the FLUKE-9144 dry calibration furnace was selected as the heat source for the temperature test. The test results show that the system has fast acquisition speed, high measurement accuracy and good temperature stability.

Temperature measurement is a very important measurement project in spacecraft vacuum thermal test, and thermocouple measurement system is generally used for temperature measurement. In order to reduce the number of wire measuring circuit and improving the measurement system of anti disturbance and high measurement accuracy in vacuum thermal test process, which can be used in digital temperature measurement system of vacuum thermal test design, realizes the digital temperature measuring equipment of spacecraft and ground equipment. The system is composed of digital temperature sensor DS18B20 and acquisition device. It can be connected with remote monitoring computer through LAN network to realize remote monitoring of temperature. The hardware structure, communication protocol and software design of the digital temperature measurement system are given in this paper. The vacuum thermal environment test and comparison with the platinum resistance temperature measurement system. The results show that the stability of the system is good and the difference between the measured value and the PT100 measurement is within 0.5 °C, and the linearity is about ±0.1% which satisfies the requirement of vacuum thermal test.

The communication power supply need to meet the requirements of high dynamic and steady state, so as to ensure the stability when disturbed. V2C control method is studied by analyzing the effect of the parameters on the output with the help of small signal model. Then the V2C adaptive control method based on fuzzy rules is put forward to improve dynamic response and stability of system when disturbed, which is realized by changing the weight of voltage and current in feedback in real time. Finally, the advantages of the controller are verified by simulation and experiments. The results show that the V2C adaptive control method improves the dynamic performance and the accuracy of the converter in the full range of load, while the stability is better. At the same time, the stability is improved and the output characteristic is optimized.

It is discussed that the changing of parameters in the battery pack model affects the control accuracy and dynamic response of the charging system, through establishing the peak current small signal model of the full-bridge converter and load battery packs' model of the charging system. Moreover, the disadvantages of fixed parameters PID control are put forward. An online identification method is presented for battery pack charging parameters, which is based on a relay feedback system. According to the results of parameters identification, a self-tuning method is presented to regulate controller parameters in order to make the charging system obtain the specified crossover frequency and phase margin. As a consequence, the impact of input voltage fluctuations of chargers and characteristics change of the battery pack in charging process is mitigated for battery pack in charging process is mitigated for battery pack charging system stability and dynamic performance.

Naour Françoise, Zhenwei Li. « Trois vieux ormes », de Li Zhenwei. In: Perspectives chinoises, n°46, 1998. pp. 52-59.

Proteases are industrially important enzymes and have niche applications in diagnostic kits that use cell lysis and thereby require high resistance towards chaotropic salts and detergents, such as guanidinium chloride (GdmCl) and sodium dodecylsulfate (SDS). Subtilisin E, a well-studied serine protease, was selected to be re-engineered by directed evolution into a “chaotolerant” protease that would be resistant towards GdmCl and SDS, for application in diagnostic kits. In three iterative rounds of directed evolution, the variant SeSaM1-5 (S62I/A153V/G166S/I205V), designated as M4, was generated, with improved activity (330% on Suc-AAPF-AMC) and increased half life in 1 M GdmCl (27 fold)). Two other variants, M5 (S62I/A153V/G166S/T224A/T240S) and M6 (S62I/ A153V/G166S/I205V/N218S/T224A) were constructed by combination of additional beneficial substitutions for further improvement of activity and resistance towards GdmCl and SDS. Inactivation curves showed that the activity of M6 towards Suc-AAPF-pNA as substrate was much improved compared to M4 in the presence of up to 5 M GdmCl (IC50 (M4): 2.7 M; IC50 (M6): 4.6 M) and up to 4% SDS (IC50 (M4): 1.5% ; IC50 (M6): 4.0%). Half life value of M6 in the presence of GdmCl was also increased (3 M GdmCl: t1/2 68 min; 2% SDS: t1/2 66 min). M5 was slightly more active in GdmCl but less active in SDS compared to M4. Additionally M5 was more active towards complex protein substrate (Azocasein) when compared to both M4 and M6. However, M5 was not stable in GdmCl or SDS in terms of its half life. Circular dichroism (CD) spectra analysis showed that secondary structures of subtilisin E wild type and three mutants (M4, M5 and M6) were almost intact at lower concentrations of GdmCl (1-2 M) and SDS (0.5-2.0%), indicating inactivation precedes conformation changes in subtilisin E in the presence of chaotropic agents. Finally, model building, molecular docking and molecular dynamics (MD) simulations of subtilisin E wild type showed that the guanidinium cation (Gdm+) or the monomeric dodecylsulfate anion (DS-) are likely to directly interact with the active site or substrate binding pocket residues, probably limiting the access of the substrate to the catalytic centre. Simulations of M4 indicated that the residues forming part of the active site or substrate binding pocket of the mutant are less affected or accessible by Gdm+ or DS-.

Abstract: the orbit determination exclusively using single station SLR(Satellite Laser Ranging) data is unviable,which limits the application of SLR technology in the observation of space debris. The paper puts forwardthat the orbit determination can be achieved through u sing SLR data assisted by the proper weighted telescopepointing data of the SLR system. To process the SLR data of AJISAI satellite by the above method, the dataconsist of the orbital arcs with 3-day spans, the precision of orbit determination is about 10 cm. Discussionshows that space debris orbit determination by the above method is also feasible.Keywords: Orbit Determination, Satellite Laser Ranging, Telescope, Residual Analysis 1. INTRODUCTION Satellite laser ranging (SLR) uses lasers to measure ranges from ground stations to satellite borne retro-re”ectorsto the millimeter level. 1,2 The applicationofSLR observationdata inspacegeodesy, geodynamics, andgeophysicshas obtained fruitful production and it has experienced continuous and highly development.

The paper deals with a rule-based real-time scheduling and control expert system (ES) for EMS. The new scheduling rules were proposed, in which the ES can schedule production when no-inputs or full-outputs (blockings) take place. Evaluation Petri Nets were combined with Predicate/Transition Nets, Coloured Petri Nets, High Level Petri Nets and Petrillo Nets, to propose the new Extended High Level Evaluation Petri Nets (EHLEP-N) which are more suitable for modelling FMS. Merging the ES with the EHLEP-N leads to more descriptive. inferential and decisive power. As a result of them. the ES has met the demand of production.

Estimation of the time of death (post-mortem interval, PMI) is occasionally a critical issue in adjudication of a criminal or civil action. But no objective and precise means has been derived for estimating PMI.One reason for this outcome may be the fact that most of these methods attempted to characterize PMI by a few or even just one specific parameter's variable in constant ambient temperature. It is crucial that we reduce or eliminate the effect of temperature variation in the estimation of PMI. Here we show the first results by using proton magnetic resonance spectroscopy (1H-MRS) technique to determine the order of degradation of certain substances, present in the brain tissue of a rabbit model, under different temperatures; our goal is to reduce or eliminate the temperature effect in the estimation of PMI.

Ketoprofen, a non-steroidal anti-inflammatory drug with well-known anti-inflammatory, antipyretic and analgesic properties, has low solubility in water and causes local or systemic disturbance in the gastrointestinal tract. In the present study we investigated the potential of polyamidoamine (PAMAM) dendrimers as drug carriers of ketoprofen by in vitro and in vivo studies. The in vitro release of ketoprofen from the drug-dendrimer complex is significantly slower compared to pure ketoprofen. Anti-nociceptive studies using the acetic acid-induced writhing model in mice showed a prolonged pharmacodynamic behavior for the ketoprofen-PAMAM dendrimer complex. Also, the blood level studies were investigated. We concluded that PAMAM dendrimers might be considered as a potential drug carrier of ketoprofen with a sustained release behavior under suitable conditions.

The microstructure evolution and the tensile properties of the second generation single crystal superalloy DD6 were investigated after full heat treatment and aging process at 980–1200 °C. The results indicate that the morphological instability occurs at relatively high temperature, and the γ ' phase gradually connects and rafts after aged for 800 h at 1050 °C. After aged for 100 h at 1200 °C, the γ / γ ' microstructure cubicity gradually becomes weaker and transforms into spherical boundary, accompanied with a few finer matrix phase embedded into strengthening phases. Whereas the dislocation lines are homogeneously distributed in the γ / γ ' interface area, and dislocation motions are also strengthened with increasing of aging time and temperature. After aged at 1050 °C for 1000 h, the precipitation phase in the form of blocky appears in the enrichment areas of solution strengthening elements and its brittle characteristics will pile up dislocation motions at lower temperature. The ultimate tensile strength, yield strength and elongation percentage decrease with increasing of aging time, while a fluctuation of contraction area will occur at 760 °C

Recent advances in quantum mechanical (QM)-based molecular dynamics (MD) simulations have used machine-learning (ML) to predict, rather than recalculate, QM-accurate forces in atomic configurations sufficiently similar to previously encountered ones. Here, we discuss how ML approaches can be deployed within large-scale QM/MM materials simulations on massively parallel supercomputers, making QM zones of 1000 atoms routinely attainable. We argue that the ML approach allows computational effort to be concentrated on the most chemically active subregions of the QM zone, significantly improving the overall efficiency of the simulation. We thus propose a novel method to partition large QM regions into multiple subregions, which can be computed in parallel to achieve optimal scaling. Then we review a recently proposed QM/ML MD scheme (Z. Li, J.R. Kermode, A. De Vita Phys. Rev. Lett., 2015, 114, 096405), discussing how this could be efficiently combined with QM-zone partitioning. VC 2015 Wiley Periodicals, Inc.

We present a molecular dynamics scheme which combines first-principles and machine-learning (ML) techniques in a single information-efficient approach. Forces on atoms are either predicted by Bayesian inference or, if necessary, computed by on-the-fly quantum-mechanical (QM) calculations and added to a growing ML database, whose completeness is, thus, never required. As a result, the scheme is accurate and general, while progressively fewer QM calls are needed when a new chemical process is encountered for the second and subsequent times, as demonstrated by tests on crystalline and molten silicon.