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Effective CO2transformations hold essential significance for carbon neutrality and sustainable energy development. Carboxylative cyclization of propargylic amines with CO2serves as an atom-economic reaction to afford oxazolidinones, showing broad applications in organic synthesis and pharmaceutical fields. However, most catalysts involved noble metals, exhibited low efficiency, or required large amounts of base. Hence, it is imperative to explore alternative noble-metal-free catalysts in order to achieve efficient conversion while minimizing the use of additives. Herein, a novel nanopore-based Cu(II)–organic framework (1) based on a new imidazole carboxylic ligand was successfully constructed and exhibited excellent stability. Catalytic investigations revealed that the combination of 1with 1,4-diaza[2.2.2]bicyclooctane (DABCO) efficiently catalyzed the carboxylative cyclization of propargylic amines with CO2, achieving turnover numbers of 142 based on the catalyst and 7.1 based on DABCO. 1as a heterogeneous catalyst maintained high catalytic performance even after being reused at least 5 cycles, with its structure remaining stable. The strong activation of Cu(II) cluster nodes of catalyst 1toward −NH– groups within organic substrates, as demonstrated by mechanism experiments, along with excellent CO2adsorption performance and the presence of regular 1D channels, synergistically facilitates the reaction rate. This research presents the first instance of a Cu(II)–organic framework achieving this cyclization reaction, offering wide prospects for novel catalyst design and CO2utilization.

This article aims to unify spatial dependency and temporal dependency in a non-Euclidean space while capturing the inner spatial–temporal dependencies for traffic data. For spatial–temporal attribute entities with topological structure, the space–time is consecutive and unified while each node’s current status is influenced by its neighbors’ past states over variant periods of each neighbor. Most spatial–temporal neural networks for traffic forecasting study spatial dependency and temporal correlation separately in processing, gravely impaired the spatial–temporal integrity, and ignore the fact that the neighbors’ temporal dependency period for a node can be delayed and dynamic. To model this actual condition, we propose TraverseNet, a novel spatial–temporal graph neural network, viewing space and time as an inseparable whole, to mine spatial–temporal graphs while exploiting the evolving spatial–temporal dependencies for each node via message traverse mechanisms. Experiments with ablation and parameter studies have validated the effectiveness of the proposed TraverseNet, and the detailed implementation can be found from https://github.com/nnzhan/TraverseNet.

For solving large-scale nonlinear equations, a nonlinear fast deterministic block Kaczmarz method based on a greedy strategy is proposed. The method is adaptive and does not need to compute the pseudoinverses of submatrices. It is proved that the method will converge linearly to the nearest solution to the initial point under mild conditions. Numerical experiments are performed to illustrate that the method is efficient at least for the tested problems.

A compound control method based on adaptive high-order fast non-singular terminal sliding mode control (AHONFTSMC) and sliding mode disturbance observer is investigated in this paper, so as to shorten the response time of speed tracking, and improve the perturbation resistance of torque pulsation in permanent magnet synchronous motors. Firstly, considering the contradictory requirement of achieving both rapid response and mitigating severe jitter in traditional non-singular terminal sliding mode control (NFTSMC), an adaptive parameter technique is proposed to enhance the system’s dynamic response. AHONFTSMC not only ensures the system’s good tracking performance, but also effectively reduces the jitter in the control output. Secondly, a nonlinear disturbance observer is established to further improve the system response accuracy, so as to observe the disturbance differentials in the system, and perform feedforward compensation on the controller. The stability and convergence of the designed compound controller are demonstrated through the application of Lyapunov theory. The experimental results demonstrate notable improvements in the motor controlled by AHONFTSMC, especially compared to sliding mode control (SMC) and NFTSMC methods. Specifically, compared to SMC and NFTSMC, the time required to reach the rated speed is reduced by 68.6%, 15.6% respectively. The speed overshoot is reduced by 22 and 3% respectively. Compared to the non-adaptive HONFTSMC method, the time required to reach the rated speed is reduced by 7.3%. Furthermore, AHONFTSMC ensures stable changes in electromagnetic torque, effectively reducing the occurrence of chattering. These findings confirm that the proposed control strategy significantly enhances the accuracy of system control and improves the overall dynamic performance of the system.

Recently, an emerging category green of energetic material ammonium dinitramide (ADN) has exhibited promising application in propellants due to its outstanding merits in energy release and environmental friendliness. It can be considered to substitute traditional oxidizer of ammonium perchlorate (AP) in military systems and aerospace. In this paper, a novel spherical energetic composite ADN/copper alginate (CA) with a microporous structure was designed and prepared by the W/O gel emulsion method, and a desirable porous microsphere structure was obtained. Multiple characterization techniques were used to investigate the structure and properties of ADN/CA composites. The results showed that ADN crystals were homogeneously encapsulated in an alginate-gel matrix. Thermal decomposition temperature was reduced to 151.7 °C compared to ADN, while the activation energy of them was reduced from 129.73 kJ/mol (ADN) to 107.50 kJ/mol (ADN/CA-4). In addition, as-prepared samples had lower impact and frictional sensitivity than ADN. The mechanism of sensitivity reduction and decomposition are also discussed. Constant-volume combustion tests show that peak pressure of the ADN/CA-4 achieves 253.4 kPa and pressurization rate of 2750.4 kPa/s. Hence, this has a promising application in improving the combustion performance and safety performance of solid propellants.

ABSTRACT This paper investigated the rheological properties of cement paste containing high volume circulating fluidized bed fly ash (CFBFA) using a rheometer. The effects of fly ash (type, content, particle [...]

Regular nanogels have been demonstrated their inefficiency for subterranean oil recovery due to their intrinsic drawbacks of fast swelling within minutes, thermal instability, and salinity vulnerability. Prior deployment of swelling delayed nanogels mainly depended on the reservoirs at a relatively higher temperature. To address the issues encountered during engineering deployment, hereinwe devised an integrative approach to in situform swelling delayed robust nanogels by introducing radically active monomers with thermally sensitive moieties. The nanoparticles with hydrophobic cores in brine in response to thermal input in situgenerated well-dispersed hydrophilic nanogels, which showed a pronounced delayed swelling of a week compared to traditional nanogels showing swelling kinetics within minutes. Furthermore, the formation of swelling-delayed nanogels could occur at ambient temperature. This behavior was radically different from that of temperature-controlled labile cross-linkers containing nanogels, requiring temperatures greater than 50 °C for volume increase thanks to ester hydrolysis. In addition, the in-situformed nanogels displayed long-term thermal stability and salinity tolerance under hostile media at temperatures up to 130 °C. The release of an acidic proton under aqueous conditions has been demonstrated to control the microenvironment for various scenarios. The nanotechnology of converting hydrophobic nanoparticles to hydrophilic nanogels could be applied in a wide range of practical applications such as plugging materials and foaming stabilizers for in-depth conformance control during water and CO2flooding.

Aim:The purpose of this study was to investigate the effect of esmolol (ES) on LPS-induced cardiac injury and the possible mechanism. Methods:Sepsis was induced by i.p. injection of LPS (10 mg/kg) in male Sprague-Dawley rats pretreated with ES, 3-methyladenine or rapamycin. The severity of myocardial damage was analyzed by hematoxylin-eosin staining, and myocardial damage scores were calculated. The concentration of cardiac troponin was measured by enzyme-linked immunosorbent assay. The expression of autophagy-related proteins (beclin-1, LC3-II, p-AMPK, p-ULK1, p-mTOR) in myocardial tissue was detected by Western blotting. Autophagosome formation and the ultrastructural damage of mitochondria were assessed using transmission electron microscopy. Results:LPS induced an increase in myocardial damage score in a time-dependent manner, accompanied with an increase in autophagy at 3 h and decrease in autophagy at 6, 12, and 24 h. Pretreatment of LPS-treated rats with ES or rapamycin reduced myocardial injury (release of cardiac troponin, myocardial damage score) and increased autophagy (LC3-II, beclin-1, p-AMPK, and p-ULK1 levels and autophagosome numbers) at 12 and 24 h. In contrast, 3-methyladenine showed no effect. Conclusion:Esmolol alleviates LPS-induced myocardial damage through activating the AMPK/mTOR/ULK1 signal pathway–regulated autophagy.

This paper presents an investigation on the compressible flow past spanwise wavy wings with an incoming flow of and . The scale adaptive simulation is employed here to solve the Favre-averaged equations. Three wings, with the ratio of wavelengths (λ) to chord length (c) respectively equaling to 1/2 (W4), 1/3 (W6), 1/4 (W8), are aerodynamically investigated. The aerodynamic force and separation were compared. The results obtained show that the lift-to-drag ratio of W-8 is 12.7% and 14.4% higher than W-4 and W-6 because of the larger low-pressure regions, while the lift and drag coefficient curves of W-8 oscillate more strongly. Leading edge separated bubbles and dilation-type recirculation regions are observed in the flow field structures. Spanwise momentum transportation and local airflow downwash effect are generated by the flow around the separation regions. Spanwise momentum transportation and downwash effect play important roles in the flow control mechanism of spanwise wavy wings. Three components of three-dimensional velocity vectors are modally decomposed by dynamic mode decomposition method to reveal the flow control mechanisms and vortex structures. The main modes characterizing the motions of arched vortices and shear layer vortices have been obtained. Strouhal number (St) is adopted to define the periodic oscillations of vortex shedding. The Stof the modes are related to the scale of the vortex structures in the flow field. Small-scale eddy motions have been decomposed in high-frequency modes, and thus the modes of the flow field are more meticulous for higher St.

Arginine vasopressin (AVP) and oxytocin (OT) influence social behavior and cognitive processes and may explain some of the variance associated with individual differences in behavior. Although great focus has been placed on the roles of these peptides in learning and memory, less attention has been given to the receptors to which they bind. The authors exposed male prairie voles (Microtus ochrogaster) to novel females in a multitrial social recognition test to investigate whether individual differences in vasopressin receptor (VlaR) or oxytocin receptor (OTR) related to social recognition. The authors also explored differences in OTR and VlaR throughout the brain to determine whether patterns of receptor coexpression emerged in functionally related structures. Male investigation of females was highly variable, and those that investigated females the most did not habituate to repeated female presentation. Moreover, high investigators expressed significantly more VlaR and less OTR in the lateral septum. Coexpression patterns of these receptors emphasize the role of OT and AVP in neural circuits involved in social behavior, reward, learning, and memory. Understanding individual differences in the laboratory may provide insight into evolved natural behavior. Keywords: individual differences, lateral septum, prairie vole, social behavior network, social recognition

Layered double hydroxides (LDHs), a class of two-dimensional (2D) brucite-like layers, have been effectively applied in diverse fields. However, the current synthesis methods restrict the in situscaling-up and tunable production of LDH-based materials. Inspired by the growing characteristic of “Bryophyllum pinnatum”, a sacrificial co-sputtered Zn−Al transition layer was introduced for the first time to in situgrow a scalable-manufactured and thickness-controllable LDH film on arbitrary substrate materials with flexible shapes through “partial dissolution” and “solution infiltration” processes. Diverse LDH films could be tailored by the creative regulation of the component, structure and surface state of the transition layer. Results showed that the as-prepared LDH film had strong mechanical robustness under harsh abrasion conditions due to its large thickness and multi-level microstructure. Moreover, a series of galvanic couple model experiments based on Zn/Al single-metal transition layers were designed to solve the real-time monitoring issue in the complex hydrothermal solution. This work not only develops a new strategy to design and grow in situLDH films with multifaceted features, but also reveals sophisticated LDH formation mechanisms. Hence, the findings of this study may broaden the practical application of LDH-based materials toward advanced and smart devices.

Understanding the impact of substituents on the quantum interference effect at single molecule scale is of great importance for the design of molecular devices. In this work, three platinum(II) complexes with –H, –NH2and –NO2groups on conductive backbones were designed and synthesized. Single-molecule conductance, which was measured using scanning tunnelling microscope break junction (STM-BJ) technique, demonstrated a conductance freeze phenomenon under the variation of substituents. Theoretical study revealed that, despite the electronic effect of the substituents shifting the energy level of molecular orbital, the quantum interference effect vanished the influence of electronic effect on the conductance and eventually leaded to the conductance freeze.

The scale of Plectropomus leopardusbreeding is continually expanding, and this has necessitated constant changes to ensure that breeding conditions are optimized. Background color is an important factor affecting fish feeding. In this study, fish (10.58 ± 0.03 g) were cultured on five background colors (red, blue, black, white, and transparent), and the growth status and intestinal microbes of these fish over 56 days were analyzed. Growth performance and the expression of growth-related genes were optimized when the background color was white. The white group had higher AMS and LPS enzyme activities and lower T-SOD and T-AOC enzyme activities, indicating that the white background could effectively promote feeding and reduce oxidative stress in P. leopardus. Additionally, changes in background color altered the composition and function of the intestinal microbiota. The diversity and abundance of intestinal microbiota, including the abundance of beneficial bacteria, were highest in fish on a white background. The abundances of Firmicutes and Actinobacteriota and the abundance of Bacilluswere higher in the White group than in the other groups, indicating that a white background promotes the health of juvenile P. leopardus. In conclusion, a white background can promote the growth performance of P. leopardusand increase the abundance of beneficial intestinal microbes. Generally, the results of our study could be used to optimize the culture of P. leopardus.

Oil transport is greatly affected by heterogeneous pore–throat structures present in shale. It is therefore very important to accurately characterize pore–throat structures. Additionally, it remains unclear how pore–throat structures affect oil transport capacity. In this paper, using finite element (FE) simulation and mathematical modeling, we calculated the hydrodynamic resistance for four pore–throat structure. In addition, the influence of pore throat structure on shale oil permeability is analyzed. According to the results, the hydrodynamic resistance of different pore throat structures can vary by 300%. The contribution of additional resistance caused by streamline bending is also in excess of 40%, even without slip length. Furthermore, Pore–throat structures can affect apparent permeability by more than 60% on the REV scale, and this influence increases with heterogeneity of pore size distribution, organic matter content, and organic matter number. Clearly, modeling shale oil flow requires consideration of porous–throat structure and additional resistance, otherwise oil recovery and flow capacity may be overestimated.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cor.2005.02.028 Byline: Ling Wang (a), Liang Zhang (b), Da-Zhong Zheng (a) Abstract: As a typical manufacturing and scheduling problem with strong industrial background, flow shop scheduling with limited buffers has gained wide attention both in academic and engineering fields. With the objective to minimize the total completion time (or makespan), such an issue is very hard to solve effectively due to the NP-hardness and the constraint on the intermediate buffer. In this paper, an effective hybrid genetic algorithm (HGA) is proposed for permutation flow shop scheduling with limited buffers. In the HGA, not only multiple genetic operators based on evolutionary mechanism are used simultaneously in hybrid sense, but also a neighborhood structure based on graph model is employed to enhance the local search, so that the exploration and exploitation abilities can be well balanced. Moreover, a decision probability is used to control the utilization of genetic mutation operation and local search based on problem-specific information so as to prevent the premature convergence and concentrate computing effort on promising neighbor solutions. Simulation results and comparisons based on benchmarks demonstrate the effectiveness of the HGA. Meanwhile, the effects of buffer size and decision probability on optimization performances are discussed. Author Affiliation: (a) Department of Automation, Tsinghua University, Beijing, 100084, PR China (b) Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109-2122, USA

Theoretical and experimental explorations have demonstrated that both anisotropy and unstable stratification exist in general ocean turbulence. Recent analyses of temporal broadening of ultrashort optical pulses in oceanic turbulence have adopted the assumptions that the propagation path in the z direction was isotropic, or turbulent cells are simply premised on circular symmetry in the xy plane. In this paper, circular symmetry of turbulent cells in the xy plane is no longer maintained, and two anisotropic factors describing the anisotropic scales in the xy plane are introduced to study the temporal broadening of ultrashort optical pulses. Moreover, unstable stratification of oceanic turbulence indicates the eddy diffusivities of temperature and salt are no longer equal. By Rytov approximation and the temporal-moments method, a new model is proposed for the temporal broadening of ultrashort optical pulse propagation in general ocean turbulence. We focus on the effects of asymmetric turbulent cells, unstable stratification, and other characteristics in general ocean turbulence on the temporal broadening. This work provides a theoretical basis for improving the transmission quality of ultrashort optical pulses and the performance of underwater optical communication systems.

The Umenocoleidae is among the most perplexing fossil insect taxa, widespread at lower and middle latitudes during the Early Cretaceous and probably becoming extinct after the mid-Cretaceous. This problematic taxon was first described from the Lower Cretaceous of China and has been variously assigned to stem-group Coleoptera, Protelytroptera, Blattaria, stem-group Dictyoptera, or Mantodea. The systematic position of the enigmatic family — especially its type species Umenocoleus sinuatusChen et T’an, 1973— has remained highly controversial owing to the lack of preserved phylogenetically informative or diagnostic characters. Here, we describe a new specimen of the type species from the type horizon of the type locality (Lower Cretaceous Zhonggou Formation at Jiuquan, Yumen City, China), and additionally two forewings of Ponopterix. We found that the Umenocoleidae is similar to stem-group Coleoptera in its forewing venation but differs in its multi-segmented antennae, orthognathous orientation of the head, subdivision of the pronotum by a transverse furrow, ultrastructure of the forewing punctures, and unfolded hindwings. Our phylogenetic analysis, using an extended matrix of 72 characters and 37 taxa, indicates that the Umenocoleidae is likely a specialized taxon of Dictyoptera, sister to Alienoptera. The beetle-like appearance is interpreted to be a result of convergent evolution.

The all-photonic quantum repeater (APQR) is a promising repeater scheme to realize long-distance quantum communication. For a practical APQR, an indispensable requirement is the robustness of the repeater graph state (RGS) against photon loss. We propose a new loss-tolerant scheme by applying the generalized Shor code to RGS, which can be experimentally demonstrated with current technology. Experimentally, we first prepare and verify the nine-qubit Shor code. Then, by applying the generalized Shor code to APQR and preparing a simplified encoded RGS with the structure of 1×2 based on the Shor code state, the effectiveness of our loss-tolerant scheme and the loss tolerance of the encoded RGS are respectively verified. Our results make an essential step toward a practical APQR and enrich the research of quantum error correction code.

In this study, we introduce the phase correlation arc of an orbital angular momentum (OAM) beam to investigate the evolution of OAM entanglement. We reveal that the entanglement decay of all OAM states of Laguerre–Gaussian modes in atmospheric turbulence is universal via both numerical predictions and experimental data. A similar evolution law is also theoretically confirmed to exist in Bessel–Gaussian modes. Finally, by using the phase correlation arc, the precise formula of the decay distance dependence on the OAM number is derived, and it exhibits excellent agreement with previous experimental conclusions.

In this paper, a novel and effective stiction detection method is proposed by combining K-means clustering and the moving window approach. As a byproduct, the proposed stiction detection method offers an estimation for the stiction band in sticky control valves. The proposed stiction detection method is tested in industrial case studies consisting of benchmark industrial control loops and control loops from an oil sands industry. In the benchmark industrial control loops, the results of the proposed method are compared with some of the existing stiction detection methods. This comparison shows superior performance of the proposed method. It is noticed through a simulation case study and an industrial case study that the proposed method not only provides stiction band estimation but also can detect severe valve stiction or unexpected valve closures.

Distributed quantum metrology can enhance the sensitivity for sensing spatially distributed parameters beyond the classical limits. Here we demonstrate distributed quantum phase estimation with discrete variables to achieve Heisenberg limit phase measurements. Based on parallel entanglement in modes and particles, we demonstrate distributed quantum sensing for both individual phase shifts and an averaged phase shift, with an error reduction up to 1.4?dB and 2.7?dB below the shot-noise limit. Furthermore, we demonstrate a combined strategy with parallel mode entanglement and multiple passes of the phase shifter in each mode. In particular, our experiment uses six entangled photons with each photon passing the phase shifter up to six times, and achieves a total number of photon passes N?=?21 at an error reduction up to 4.7?dB below the shot-noise limit. Our research provides a faithful verification of the benefit of entanglement and coherence for distributed quantum sensing in general quantum networks.

The volcano-shaped relation between binding energies of reaction intermediates and catalytic activities underpins the binding energy approach, a prevailing guideline, in electrocatalysis. Pt, Ir, and Rh belong to the over-adsorbing leg of the volcano plot and adsorb oxygen-containing intermediates in an intensifying order. Therefore, the binding energy approach predicts an activity order of Pt > Ir > Rh for ORR. Herein, single crystal experiments corroborate the binding strength order of Pt < Ir < Rh but give out an ORR activity order of Pt > Rh > Ir, contradicting the binding energy approach. To understand this discrepancy, we develop a microkinetic ORR model that complements the standard binding energy approach by including multistep kinetics corrected with double layer effects. Armed with this model, we extract binding energies from cyclic voltammogram, quantitatively fit the polarization curves of all three metals, and attribute the higher ORR activity of Rh than Ir to a lower activation barrier of OHaddesorption because Ir possesses a higher magnitude of the surface charge, inducing a more rigid layer of adsorbed water at the metal surface. A key message delivered here is that kinetic and double layer effects are nontrivial for ORR on the single crystalline electrodes studied here.

AbstractStudies regarding sport-related sudden cardiac death (SCD) mainly focus on competitive athletes; similar data are rare in the general population, especially in China. We conducted a retrospective study (from September 1998 to August 2013) to investigate the aetiological distribution and epidemiological features of sport-related SCD in Southern China. Selections of cases are based on details, and two subgroups were established: one was the sport-related SCD group, and the other was the disease-free accident victims group which was matched with the sport-related SCD group in gender, age and year of death. Among the 3770 sudden-death cases, 1656 cases were SCD cases. A total of 65 cases (57 males) out of 1 656 SCD cases were sport-related. The age range of the 65 sport-related SCD cases was from 12 to 68 years old with a mean (35.92 ± 14.23) years old. Only two of these cases were competitive athletes. The most common circumstances of the 65 sport-related SCD cases were heavy physical labour (46.15%) and running (30.77%). The three leading forensic diagnoses were the coronary atherosclerotic disease (CAD, 28 cases), cardiomyopathy (CM, 14 cases) and sudden unexplained death (7 cases). CM was the most common forensic diagnosis in those ≤35 years old, while CAD was the most common one in those >35 years old. Left anterior descending in which atherosclerotic plaques was most commonly found was the principal artery branch associated with sport-related SCD. There was a statistically significant difference in the weight of hearts between the 65 sport-related SCD cases and 65 diseases-free accidental cases. This study highlights the need to attract public attention to sport-related SCD and to issue a prevention strategy to the public, and to make the SCD-related genetic sequencing a routine tool in both forensic pathological examination and clinic screening.

AbstractAutopsy is of great significance for elucidating the pathological changes, pathogenesis and cause of death of Coronavirus Disease 2019 (COVID-19) and can provide a theoretical basis for scientific and accurate prevention and control of its outbreak. Based on related laws and regulations, such as the Law of the People’s Republic of China on Prevention and Control of Infectious Diseases, clinical manifestations and epidemiological characteristics of COVID-19 and guidelines on the prevention and control of this epidemic, combined with the practical work of forensic pathology examinations, we developed the Guide to Forensic Pathology Practice for Death Cases Related to Coronavirus Disease 2019(COVID-19) (Trial Draft). This guide describes the background investigation of the death cases, autopsy room requirements, personal prevention and protections, external examinations, autopsy practices and auxiliary examinations, and thus offers a reference for forensic and pathological examination institutions and staff.

Quantum repeaters—important components of a scalable quantum internet—enable entanglement to be distributed over long distances. The standard paradigm for a quantum repeater relies on the necessary, demanding requirement of quantum memory. Despite significant progress, the limited performance of quantum memory means that making practical quantum repeaters remains a challenge. Remarkably, a proposed all-photonic quantum repeater avoids the need for quantum memory by harnessing the graph states in the repeater nodes. Here we perform an experimental demonstration of an all-photonic quantum repeater. By manipulating a 12-photon interferometer, we implement a 2 × 2 parallel all-photonic quantum repeater, and observe an 89% enhancement of entanglement-generation rate over standard parallel entanglement swapping. These results provide a new approach to designing repeaters with efficient single-photon sources and photonic graph states, and suggest that the all-photonic scheme represents an alternative path—parallel to matter-memory-based schemes—towards realizing practical quantum repeaters. An all-photonic quantum repeater is demonstrated by manipulating state-of-the-art 12-photon interferometry. The enhancement of entanglement-generation rate compared with parallel entanglement swapping proves the feasibility of the concept.

Introduction of (S)-configuration is the key step in the synthesis of the anti-dementia drug Rivastigmine. Twenty-one alkylation products were obtained through simple washing with hexane/ethyl acetate (v/v: 10/1) in good yields (>85%) and high diastereoselectivity (up to >99:1 dr). Moreover, the chiral auxiliary could be easily dissociated and readily regenerated. That is, the synthesis was proved to follow group-assisted purification (GAP) chemistry/technology. In addition, the chiral amine produced by this asymmetric alkylation reaction was effectively used in the synthesis of Rivastigmine.Twenty-one alkylation products were obtained through simple washing with hexane/ethyl acetate (v/v: 10/1) in good yields (>85%) and high diastereoselectivity (up to >99:1 dr). That is, the synthesis was proved to follow the GAP chemistry/technology. In addition, the chiral amine produced by this asymmetric alkylation reaction was effectively used in the synthesis of Rivastigmine.

A wavelength-sensitive plasmonically induced transparency-like (PIT-like) device consisting of a double-layer graphene-based metal–dielectric–metal (MDM) waveguide is proposed. We initially investigate monolayer graphene sandwiched in the MDM waveguide and utilize the phase-matching equation to explain the reflected resonant wavelength of the transmission spectra. The PIT-like windows in the transmission spectra of double-layer graphene can be achieved by tuning the applied bias voltage on the graphene layer and the distance between the graphene layer and metal substrate. We can obtain the high-performance PIT-like devices with a flexible on–off–on effect. We use a finite element method to do all related simulations.

We consider the non-horizontal distributions of orbital angular momentum biphotons through free-space atmospheric channels, in which case the non-Kolmogorov turbulent effects shall be considered. By considering the case of initial non-perfect resource, i.e., the orbital angular momentum biphotons are initially prepared in an extended Werner-like state, we investigate the non-Kolmogorov effects on the propagations of nonclassical correlations, including quantum entanglement and quantum discord. It is found that universal decay laws of entanglement and discord also exist for non-Kolmogorov turbulence but with their decay curves different from that of entanglement for Kolmogorov turbulence reported by Leonhard et al. [Phys. Rev. A91, 012345 (2015)PLRAAN1050-294710.1103/PhysRevA.91.012345]. We show that the universal decay laws are dependent on the power-law exponent of the non-Kolmogorov spectrum and compare the differences of decay properties between entanglement and discord caused by non-Kolmogorov turbulence.

ABSTRACTObjectives:Notch1 regulates tumor biology in a complex, context-dependent manner. The roles of Notch1 in tongue cancer are still controversial. The aim of this study is to investigate the roles of Notch1 in tongue cancer.Materials and Methods:The expression of Notch1 was tested between tongue cancer and normal samples by using immunohistochemistry. Tongue cancer cells were transfected with siRNA or plasmid, respectively. Cell proliferation, apoptosis, migration and invasion ability were tested in appropriate ways. The subcutaneous tumor model was established to observe the tumor growth.Results:Notch1 was upregulated in tongue carcinoma tissues and the expression of Notch1 was related with tumor stage and differentiation. Overexpression of Notch1 could increase tongue cancer cells proliferation, invasion and migration. But inhibited the expression of Notch1 could decrease cells proliferation, invasion and migration and promote cell apoptosis in vitroand in vivo.Conclusion:Our results prove that the oncogenic role of Notch1 in tongue cancer and provide the direction of targeted therapy of tongue cancer.

Quantum repeaters1–4 are essential elements for demonstrating global-scale quantum communication. Over the past few decades, tremendous efforts have been dedicated to implementing a practical quantum repeater5–10 . However, nested purification1 , the backbone of a quantum repeater, remains a challenge because the capacity for successive entanglement manipulation is still absent. Here, we propose and demonstrate an architecture of nested purification using spontaneous parametric downconversion sources11 . A heralded entangled photon pair with higher fidelity is successfully purified from two copies of low-fidelity pairs that experience entanglement swapping and noisy channels. By delicately designing the optical circuits, double-pair emission noise is eliminated automatically and the purified state can be used for scalable entanglement connections to extend the communication distance. Combined with a quantum memory, our approach can be applied immediately in the implemention of a practical quantum repeater. A nested purification protocol is developed by combining entanglement purification and swapping. It works for the spontaneous parametric downconversion sources as well as other physical systems that suffer from double-pair emission noise.

ABSTRACTBrugada syndrome (BrS) is an arrhythmogenic disorder which was first described in 1992. This disease is a channelopathy characterized by ST-segment elevations in the right precordial leads and is susceptible to sudden death. BrS is a fatal disease with gender and age preferences. It occurs mainly in young male subjects with a structurally normal heart and silently progresses to sudden death with no significant symptoms. The prevalence of BrS has been reported in the ranges of 5–20 per 10 000 people. The disease is more prevalent in Asia. Nowadays, numerous variations in 23 genes have been linked to BrS since the first gene SCN5Ahas been associated with BrS in 1998. Not only can clinical specialists apply these discoveries in risk assessment, diagnosis and personal medicine, but also forensic pathologists can make full use of these variations to conduct death cause identification. However, despite the progress in genetics, these associated genes can only account for approximately 35% of the BrS cases while the etiology of the remaining BrS cases is still unexplained. In this review, we discussed the prevalence, the genes associated with BrS and the application of molecular autopsy in forensic pathology. We also summarized the present obstacles, and provided a new insight into the genetic basis of BrS.

The galvanic corrosion behavior of carbon fiber reinforced polymers (CFRPs) GM-CFRP and Tepex-CFRP in contact with a Zn-coated DP590 steel in solution containing 0.9 wt% NaCl + 0.1 wt% CaCl2+ 0.075 wt% NaHCO3was investigated. The results showed that the GM-CFRP/steel couple was initially more resistant to galvanic corrosion, but its galvanic corrosion activity gradually became higher than the Tepex-CFRP/steel couple. The different galvanic behaviors of these two couples were discussed based on the electrochemical performance of GM-CFRP, Tepex-CFRP and DP590 coupons in the testing solution.

AbstractIn this paper, we propose a new SSOR-like method with four parameters to solve the augmented system. And we analyze the convergence of the method and get the optimal convergence factor under suitable conditions. It is proved that the optimal convergence factor is the same as the GMPSD method [M.A. Louka and N.M. Missirlis, A comparison of the extrapolated successive overrelaxation and the preconditioned simultaneous displacement methods for augmented systems, Numer. Math. 131(2015) 517-540] with five parameters under the same assumption.

Coherently manipulating a number of entangled qubits is the key task of quantum information processing. In this paper, we report on the experimental realization of a ten-photon Greenberger–Horne–Zeilinger state using thin BiB_3O_6 crystals. The observed fidelity is 0.606±0.029, demonstrating a genuine entanglement with a standard deviation of 3.6σ. This result is further verified using p-value calculation, obtaining an upper bound of 3.7×10^−3 under an assumed hypothesis test. Our experiment paves a new way to efficiently engineer BiB_3O_6 crystal-based multi-photon entanglement systems, which provides a promising platform for investigating advanced optical quantum information processing tasks such as boson sampling, quantum error correction, and quantum-enhanced measurement.

Advanced water injection has become an effective method for developing low-permeability reservoirs. However, after a period of high yield from fracturing, the injected water flows rapidly along high-capacity channels, which greatly reduces the sweep efficiency of reservoirs. In this work, the plugging process by microspheres and nanospheres from the fracture to the matrix was simulated through core experiments. The plugging performance of multi-scale microspheres (microspheres and nanospheres) on the core matrix was evaluated by measuring the plugging rate and other parameters. Enhanced oil recovery after synergistic plugging with multi-scale microspheres was used as the evaluation index, a sensitivity analysis of injection parameters was performed, and the best combination of injection parameters was optimized by orthogonal experiments. The experimental results showed that the plugging performance of nanospheres is mainly reflected in the filling of the core matrix, while the plugging performance of microspheres is mainly reflected by retention at the injection end of the core (as opposed to the fractured end face). The plugging rate of nanospheres reached 78.83%, which is much higher than the 30.28% rate achieved with microspheres. The maximum oil recovery after plugging was 19.12%, which corresponds to the following combination of injection parameters: total injection of 0.6 pore volume (PV), injection ratio between nanospheres and microspheres of 2:1, injection rate of 1.5 mL·min−1, and aging time of 6 days. Among the injection parameters, the injection ratio between nanospheres and microspheres had the greatest influence on the recovery of waterflooding after plugging, followed by the total injection of multi-scale microspheres. The injection rate and aging time had little effect.

Some typical components of the Jehol Biota, including conchostracans Eosestheriasp., the mayfly Ephemeropsis trisetalisEichwald, 1864, the aquatic beetle Coptoclava longipodaPing, 1928, and a fragmentary dragonfly, are reported for the first time from the Bayingebi Formation in the Celaomiao region, western Inner Mongolia, China. This discovery indicates that the middle Upper Member of Bayingebi Formation can be correlated with the upper Yixian and the lower Jiufotang formations in western Liaoning Province. Combining it with the radio-isotopic dating result, we further believed that the Upper Member of Bayingebi Formation could be roughly correlated with the Yixian, Jiufotang, and Shahai formations, and the overlying Suhongtu Formation with the Fuxin Formation in western Liaoning Province.

In 1981, Cohen constructed an infinite family of homotopy elements ζk∈ π*(S) represented by $h_0 b_k \in Ext_A^{3,2(p - 1)(p^{k + 1} + 1)} (\mathbb{Z}/p,\mathbb{Z}/p)$in the Adams spectral sequence, where p> 2 and k⩾ 1. In the paper, we make use of the Adams spectral sequence and the May spectral sequence to prove that the composite map ζn−1β2γs+3is nontrivial in the stable homotopy groups of spheres πt(s,n)−s−8(S), where p⩾ 7, n> 3, 0 ⩽ s< p− 5 and t(s, n) = 2(p− 1)[pn+ (s+ 3)p2+ (s+ 4)p+ (s+ 3)]+s.

On 21 July 2012, a huge thunderstorm hit Beijing, prompting the city government to act immediately to deal with the emergency. Yet great losses were caused, exposing problems about urban flood control and drainage, and making people take a new look at them. It is not uncommon for a rainfall of such a degree to happen in Asia. Comparatively speaking, however, unlike in Beijing, fewer damages are caused in Taiwan, Japan and the Philippines given the same situation. In this article, therefore, the problems arising after a heavy rainfall and their solutions will be discussed.

Based on the optimal design theory, the optimization model for electric-mechanic transmission parameters is established in this paper, and genetic arithmetic is used to solve the optimization model. Comparing the transmission’s performance before optimization with that after optimization, the result shows that the motor design difficulty is reduced and the transmission’s performance is improved after optimaization.

This paper designed a new band-gap voltage reference circuit with two-stage temperature compensation.It realizes non-linear temperature compensation by using NMOS-pipe leakage current and increases the power supply rejection ratio of the band-gap voltage reference source by introducing negative feedback between the operational amplifier and the power supply. What is more, the paper simulates the band-gap voltage reference source based on CSMC 0.5μm CMOS technique. The result as follow: the band-gap voltage reference source has the temperature coefficient of 8.2ppm/oC among-40-120oC with the supply voltage of 3V, the low-frequency power supply rejection ratio is 83dBat 27oC and the power supply rejection ratio is 71dB in 1KHz, the output voltage regulation is 1.05mV/V in the supply voltage range from 2.4V to 5V.

By analyzing the problems of leakage measurement methods of coupling clamps for aircraft tubing, a new technical solution is proposed based on the gas-liquid volume equivalent replacement principle. The test prototype and dedicated measuring device are developed. The results show that the new measurement method is scientific, safe, reliable and with high accuracy. The measurement method has already been used in the production of various coupling clamps in aircraft tubing.

Oscillation during electrocatalytic oxidation of formic acid at Pt electrode under galvanostatic conditions in acidic electrolyte has been simulated based on a chemical model that involves three reaction pathways: (i) the indirect pathway via COadformation (formic acid dehydration) and oxidation; (ii) a formate pathway, involving adsorption–desorption of bridged adsorbed formate and its oxidation; and (iii) a direct pathway with successive cutting of O–H and C–H bonds. We found that only when the contribution of formate oxidation to the total formic acid oxidation current is negligible do the simulated results reproduce well the experimentally observed oscillatory patterns for electrode potential and the coverage of COadand bridge-bonded formate. It is found that the fast adsorption–desorption of both formate and OHadare responsible for the hidden negative impedance; the slow COadformation and its fast oxidation at higher potentials lead to a positive impedance. The simulated results further support the conclusion that bridge-bonded formate is not the reactive intermediate for the major pathway of formic acid oxidation at Pt electrode.