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Compared with the well-developed C–C and C–N axial chirality, the asymmetric synthesis of N–N axial chirality remains elusive and challenging. Herein we report the first atroposelective N-acylation reaction of quinazolinone type benzamides with cinnamic anhydrides for the direct catalytic synthesis of optically active atropisomeric quinazolinone derivatives. This reaction features mild conditions and a broad substrate scope and produces N–N axially chiral compounds with high yields and very good enantioselectivities. Besides, the synthetic utility of the protocol was proved by a large scale reaction, transformation of the product and the utilization of the product as an acylation kinetic resolution reagent. Moreover, DFT calculations provide convincing evidence for the interpretation of stereoselection., A highly efficient atroposelective N-acylation reaction of quinazolinone type benzamides with cinnamic anhydrides for the direct catalytic synthesis of optically active atropisomeric quinazolinone derivatives was developed.

The final instar larva of the genus Archineura Kirby, 1894 is described for the first time, based on a specimen of the Chinese endemic species Archineura incarnata (Karsch, 1892) collected from Mt. Nankunshan, Guangdong Province, China. The larva is distinguished by several characters, including its moderately slender build combined with the distinctive extremely long legs, long, narrow, uniquely spined outer caudal appendages, a mask strongly expanded anteriorly with a relatively small median cleft, and robust spines at the apex of the labial palp. The mask is most similar to larvae of Echo Selys, 1853, Mnais Selys, 1853 and Psolodesmus MacLachlan, 1870 which are considered its nearest relatives based on molecular analysis, but from which it differs in other characters. The biology of Archineura larvae is discussed briefly.

The final stadium larvae of Huosoma latiloba (Yu, Yang & Bu, 2008) and Huosoma tinctipenne (McLachlan, 1894) from Yunnan Province, China are described and illustrated for the first time, with diagnostic differences between the two species identified. While no morphological characters separating the adults of this genus, and the closely related western Palaearctic Pyrrhosoma Charpentier, 1840 have been found, the larvae of these two genera do show differences which are discussed here.

Objective: To investigate the effects of Intron on the EMT capability of non-small cell lung cancer cell line PC-9. Methods: Firstly, using the psiCHECK-2 plasmid as a basic framework to construct the recombinant plasmid of psiCHECK-2-Intron dual-luciferase reporter gene; secondly, the psiCHECK-2-Intron and psiCHECK-2 were transfected into PC-9 cells respectively. The migration and invasion abilities of PC-9 cells were analyzed by Matrigel assay. The expression changes of EMT related hallmarks, including N-cadherin, β-catenin and snail, were detected by qRT-PCR and Western Blotting. Results: Compared with the control group, the migration and invasion abilities of PC-9 cells in Intron group significantly decreased(p

Quantum dense coding properties between two identical and spatially separated atoms in free space with different initial states is investigated. It shows that dense coding capacity χ experienced a sharp decline firstly and then gradually increased to be one steady value 1 with increasing Γt. The realization of dense coding capacity χ is found to be strongly dependent on the initial states. It is worth noting that the initial pure state |ee〉 is not useful for dense coding in this system, due to the dense coding capacity χ is always less than 1(a valid dense coding capacity satisfies χ > 1). Otherwise, for the initial entangled state and mixed state, one can obtain the valid dense coding capacity, the results show that one threshold value of tc is exists, and when t < tc the dense coding capacity is valid. Tuning the atomic distance between the two atoms slightly broaden the valid dense coding region and improve the value of tc. Decreasing the purity a of initial states not only broaden the region but also prolong the effective time where one can carry out the valid dense coding successfully.

The final stadium larvae of Megalestes micans Needham, 1930 and M. kurahashii Asahina, 1985 are described and illustrated from Yunnan Province, China, and a key to the known larvae of seven species...

Objective To evaluate the effect and safety of acupuncture for the treatment of irritable bowel syndrome (IBS) through comparisons with those of polyethylene glycol (PEG) 4000 and pinaverium bromide. Patients and Methods This multicenter randomized controlled trial was conducted at 7 hospitals in China and enrolled participants who met the Rome III diagnostic criteria for IBS between May 3, 2015, and June 29, 2018. Participants were first stratified into constipation-predominant or diarrhea-predominant IBS group. Participants in each group were randomly assigned in a 2:1 ratio to receive acupuncture (18 sessions) or PEG 4000 (20 g/d, for IBS-C)/pinaverium bromide (150 mg/d, for IBS-D) over a 6-week period, followed by a 12-week follow-up. The primary outcome was change in total IBS-Symptom Severity Score from baseline to week 6. Results Of 531 patients with IBS who were randomized, 519 (344 in the acupuncture group and 175 in the PEG 4000/ pinaverium bromide group) were included in the full analysis set. From baseline to 6 weeks, the total IBS-Symptom Severity Score decreased by 123.51 (95% CI, 116.61 to 130.42) in the acupuncture group and 94.73 (95% CI, 85.03 to 104.43) in the PEG 4000/pinaverium bromide group. The between-group difference was 28.78 (95% CI, 16.84 to 40.72; P Conclusion Acupuncture may be more effective than PEG 4000 or pinaverium bromide for the treatment of IBS, with effects lasting up to 12 weeks. Trial Registration Chinese Clinical Trials Register, ChiCTR-IOR-15006259.

Optimal dense coding of a two-qubit anisotropic Heisenberg XXZ model under decoherence is investigated with the Werner state as the initial state. With the time evolution, the dense coding capacity χ oscillates firstly, and then reaches a stable value 1 in the long time limit, whatever the values of other parameters are. Our results imply that the purity r of the initial state have a strong influence on the initial value of the optimal dense coding capacity. When the purity r of the initial state increase, the initial value of dense coding capacity increase. Besides, the coupling coefficient and Dzyaloshinski-Moriya(DM) both have strong influence on the frequency of the oscillation and the area of t that the optimal dense coding is feasible(tf). Interestingly, the decoherence rate γ can strongly affect the dense coding capacity. With the decreasing of γ, the area of tf(which will make the dense coding capacity greater than 1) becomes more wider. When γ = 0, it will still allows a valid dense coding. So we can adjust the parameters to get a optimal dense coding.

The slope of the west working side of the south mining area of the open-pit coal mine where a landslide has occurred is taken as the research object. The paper selects Mohr-Coulomb elastoplastic model to analyze the slope stability of the western working side of the southern mining area of the open-pit coal mine by Finite Element Method. The numerical simulation results show that the rear edge of the sliding slope area is still in an unstable state and the front landslide mass is still in a creep state, and the local step plastic zone of the slope body is penetrated. On the basis of this, slope safeguard measures of slope cutting, backfilling and Drainage engineering to protect the slope stability are put forward. The research results provide a theoretical basis for the treatment of deformation and failure of similar slopes.

To explore the bidirectional regulation of acupuncture based on a subgroup analysis of multicenter randomized controlled trial of acupuncture withA total of 519 patients were included in the analysis, including 137 patients with constipation type irritable bowel syndrome (IBS-C) (92 cases in the acupuncture group and 45 cases in the polyethylene glycol [PEG] group), and 382 patients with diarrhea type irritable bowel syndrome (IBS-D) (252 cases in the acupuncture group and 130 cases in the pinaverium group). The patients in the acupuncture group were given acupuncture at Baihui (GV 20), Yintang (GV 29), Tianshu (ST 25), Shangjuxu (ST 37), Zusanli (ST 36), Sanyinjiao (SP 6) and Taichong (LR 3) once every other day, 3 times a week. The patients in the PEG group received polyethylene glycol 4000 powder orally, and the pinaverium group received pinaverium bromide tablets orally. All were treated for 6 weeks. The IBS symptom severity score (IBS-SSS) was assessed at baseline, treatment period (2, 4, 6 weeks of treatment) and 12 weeks of follow-up, and the IBS quality of life (IBS-QOL) score was evaluated at the baseline period, 6 weeks of treatment and 12 weeks of follow-up.The total IBS-SSS scores of the two groups of IBS-C patients at 2, 4, 6 weeks of treatment and follow-up of 12 weeks were lower than those in the baseline period (Acupuncture with

Axially chiral anilide compounds are an emerging but scarcely investigated class of stereogenic molecules with potential applications as biologically active scaffolds. Because of the lower rotation barriers, the synthesis of these compounds is a challenging task. Furthermore, the status of the limited structure type of chiral anilide constrains the latent capacity of the C–N axis as a chiral source in the application of asymmetric synthesis. Herein, we disclose an efficient protocol for the construction of the rationally designed axially chiral phosphamides via atroposelective N-allylic alkylation reaction of MBH carbonates and phosphamides. The simple hydroquinidine catalyst proves to be most efficient in this artroposelective strategy, delivering the desired axially chiral phosphamides in good yields and high enantioselectivities. In addition, a phosphamide compound, which contains both P-stereogenic center and C–N axial chirality, can be obtained by this method through a kinetic resolution process. Bec...

We investigate the effects of spin squeezing interaction, external magnetic field and temperature on dense coding capacity properties in two kinds of two-qubit spin squeezing model: one-axis twisting model (OATM) and two-axis countertwisting model (TACM). To the OATM, it is found that the value of dense coding capacity χ is larger than 1 in the region of larger values of Ω(external magnetic filed) and μ(squeezing interaction) parameters space, while in the region of lower values of Ω and μ parameters space, χ is always less than 1 and not valid for dense coding. With increasing temperature T the dense coding capacity is decayed, and one can carry out the valid dense coding in the lower T region through tuning Ω. To the TACM, it is found that the value of χ is promoted with increasing the squeezing parameter γ. Through increasing γ, χ finally reached to one stable value, which is always larger than 1 whatever value of Ω is. The valid dense coding capacity χ can be enhanced through tuning the parameter Ω or γ, but it is decreased with increasing T. Our results show that with proper enhancing the parameter Ω or γ it is easy to carry out the valid dense coding (χ > 1) and the optimal dense coding (χ = 2) when the system in TACM.

Stable and metastable vortex states in two-dimensional three-component Bose–Einstein condensates are studied in the presence of spin–orbit coupling. The ground states exhibit two skyrmion structures which respectively correspond to the d-skyrmion in antiferromagnetic or the F-skyrmion in ferromagnetic condensates. The half skyrmion and full skyrmion can be controlled by changing the strength of the spin–orbit coupling. We also find a stable composite vortex state which is associated to mixing of the ferromagnetic and antiferromagnetic manifolds.

A BINOL-based chiral phosphoric acid was employed as an efficient catalyst in enantioselective cycloaddition of ortho-hydroxyphenyl-substituted para-quinone methides and enamides, which gave rise to acetamido-substituted tetrahydroxanthenes with three adjacent stereogenic centers in high yields (up to 99%) and excellent stereoselectivities (up to >99:1 diastereomeric ratio and up to 98% ee).

To compare the curative effect on diarrhea-predominant irritable bowel syndrome (IBS-D) between acupuncture for regulatingA total of 231 patients with IBS-D were randomized into an acupuncture group (154 cases) and a western medication group (77 cases) at the ratio of 2 to 1. In the acupuncture group, acupuncture was applied to acupoint regimen for regulatingAfter treatment and in follow-up, the total scores of IBS-SSS in the patients of the two groups were all reduced as compared with those before treatment (Acupuncture for regulating

The larvae of Caliphaea angka Hämäläinen, 2003 and Mnais gregoryi Fraser, 1924 are described and illustrated for the first time from Erhai lake Basin, Yunnan Province, China. Notes on their habitat are provided. This paper represents the first verified description of the larva of Caliphaea Hagen in Selys, 1859.

In this study, we aimed to investigate the changes of lymphocyte subsets (CD3+, CD4+, CD8+) and inflammatory factors (interleukin‐6 [IL‐6], hypersensitive C‐reactive protein [HS‐CRP], and procalcitonin [PCT]) of alveolar lavage fluid in patients with severe corona virus‐2019 (COVID‐19) pneumonia and their clinical impact on the assessment of disease severity and prognosis. Twenty‐four patients with severe COVID‐19 pneumonia were admitted to the intensive care unit (ICU) of the Ezhou Central Hospital from February 1 to March 22, 2020. According to the 28‐day prognosis, they were assigned to a death group and a survival group. On the 3rd day of ICU admission, peripheral blood and alveolar lavage fluid were collected for examination of lymphocyte subsets and inflammatory factors by flow cytometry and immunoturbidimetry, respectively. The CD3+, CD4+, and CD8+ cell counts in alveolar lavage fluid and serum were significantly higher in the survival group than those of the death group (p

A biscinchona alkaloid-catalyzed AAA reaction for the construction of P-stereogenic center compounds was developed., A novel biscinchona alkaloid-catalyzed highly enantioselective desymmetrization reaction of bisphenol compounds with achiral Morita–Baylis–Hillman carbonate agents was developed. Through the asymmetric allylic alkylation strategy, a broad range of optically active P-stereogenic phosphine oxides were generated with excellent to good yields (up to 99%) and high enantioselectivities (up to 98.5 : 1.5 e.r.). The reaction was further investigated by the linear free energy relationship (LFER) analysis. A possible transition state was proposed and furthered verified by theoretical calculations.

A series of novel N-tert-butyl sulfinyl squaramide receptors have been designed and synthesized. Their interactions with a range of inorganic anions were studied in solution by 1H NMR spectroscopy. This new type of squaramide displayed better anion-binding abilities over conventional diphenyl squaramides. The single crystal analysis and DFT calulations implied the role of the tert-butyl C–H protons in binding Cl–. The energies of C–H···Cl– interactions were estimated to be 1.4–1.6 kcal/mol in solution.

General researches show that all kinds of random risk information and periodic information in the financial system are mainly transmitted to the asset price through influencing the volatility, thus impacting the whole market. So can the periodic information and random factors in the price be transmitted to the volatility in reverse and cause volatility changes? Hence, in this paper, we investigate the stochastic resonance of volatility which is influenced by price periodic information in financial market, based on our proposed periodic Brownian Motion model and absolute return volatility. The parameter estimation of the periodic Brownian Motion model is obtained by minimizing the mean square deviation between the theoretical and empirical return distributions for the CSI300 data set. The good agreements of the probability density functions of the price returns, realized volatility (RV) at 5 minutes, RV at 15 minutes and absolute return volatility between theoretical and empirical calculation are found. After simulating the absolute return volatility and signal power amplification (SPA) of volatility via periodic Brownian Motion model, the results indicated that (i) single and double inverse resonance phenomena can be observed in the function of SPA versus random information intensity or economic growth rate; (ii) multiple inverse resonance phenomena can be also observed for SPA versus frequency of periodic information. The results imply that the transmission of stochastic factors and periodic information is not only from the volatility to the price, but also from the price to the volatility.

Quantum dense coding in a two-spin squeezing model under intrinsic decoherence with different initial states (Werner state and Bell state) is investigated. It shows that dense coding capacity χ oscillates with time and finally reaches different stable values. χ can be enhanced by decreasing the magnetic field Ω and the intrinsic decoherence γ or increasing the squeezing interaction μ, moreover, one can obtain a valid dense coding capacity (χ satisfies χ > 1) by modulating these parameters. The stable value of χ reveals that the decoherence cannot entirely destroy the dense coding capacity. In addition, decreasing Ω or increasing μ can not only enhance the stable value of χ but also impair the effects of decoherence. As the initial state is the Werner state, the purity r of initial state plays a key role in adjusting the value of dense coding capacity, χ can be significantly increased by improving the purity of initial state. For the initial state is Bell state, the large spin squeezing interaction compared with the magnetic field guarantees the optimal dense coding. One cannot always achieve a valid dense coding capacity for the Werner state, while for the Bell state, the dense coding capacity χ remains stuck at the range of greater than 1.

The physics of topological defects have been extensively studied by theory and experiment in recent years. Vortex rings especially linking vortex rings are difficult to create and stabilize in experiments. We study a new structure of knot called interlocked knot in the antiferromagnetic spin-1 Bose-Einstein condensate, which has never been studied before. The interlocked knot differs from the conventional knot with linking vortex rings that are connected by a Mobius strip. It cannot be converted to untwisted rings without cutting them. We propose two schemes to generate the interlocked knot in experiments either by using an external magnetic field, or alternatively, by the spin-orbit coupling in spin-1 condensates. Our results open a new perspective for the study of knot and extend the application of experimental technique.

A highly tunable radical-mediated reaction system for the functionalization of tertiary aliphatic C–H bonds was developed. Reactions of various substrates with the Zhdankin azidoiodane reagent 1, Ru(bpy)3Cl2, and visible light irradiation at room temperature gave C–H azidated or halogenated products in an easily controllable fashion. These reactions are efficient, selective, and compatible with complex substrates. They provide a potentially valuable tool for selectively labeling tertiary C–H bonds of organic and biomolecules with tags of varied chemical and biophysical properties for comparative functional studies.

By taking into account the quantum erasing effect(QEE), the quantum discord (QD) behavior of a two-qubit system with different initial states are investigated in detail. We find that the quantum correlation can be saved under a scheme of two spatially separated atoms, each located in a leaky cavity through the quantum erasing method. It is shown that QEE can weaken the effects of decoherence, and preserve the maximum information of the coherent item. No matter whether the two atoms are in the mixted or pure state, one can robusty save their initial quantum correlation even the number of erasing events is finite. If one limit the erasing events N → ∞, the QEE can be used to protect the initial quantum correlation independently of the state in which it is stored, the values of QD is always nearly equal to the initial QD values, and it is nearly independent of the decoherence, which imply us more encourage strategy for protecting the quantum correlation properties in some quantum systems.

N-tert-Butyl sulfinyl squaramides were used for chiral discrimination of α-hydroxyphosphonates using 31P NMR. A free energy relationship study indicates that both steric and the electronic effects influence the chiral recognition of the donors.

By taking into account the nonuniform magnetic field, quantum correlation behaviors measured by concurrence and measurement-induced disturbance (MID) about a two-qubit anisotropic Heisenberg XYZ model are investigated in detail. We mainly concentrate on the differences between the entanglement and MID with the changes of different self and external control parameters. It is found that the ground state of entanglement exists the revival phenomenon, while this revival phenomenon is not included in MID. This difference is also appeared in the case of the finite temperature. Moreover, we give out the reason why the ground state entanglement and MID can behave very differently, which the former occurs the revival phenomenon whereas the latter does not. Through studying the effects about different parameters on C and MID, it presents that their magnitudes can be evidently enhanced by properly tuning B, b or adjusting the temperature. It also shows the situation which the entanglement is symmetrical with J z while MID is monotonically decreased from one constant value.

The influence of AC frequency , the content of sodium sulfate and curing time on the electrical resistivity of cemented soil was studied. Firstly, the impedance modulus of cemented soil blocks were measured and their electrical resistivity were calculated; then the primary and secondary factors influencing on the electrical resistivity of cemented soil were determined through orthogonal method; finally , the influence of three factors on cement soil resistivity was discussed qualitatively. It is found that the primary and secondary factors influencing on the electrical resistivity of cemented soil are the curing time, the content of sodium sulfate and the frequency. The electrical resistivity decreases with the increases of AC frequency and content, whereas increases with increasing curing age.

Quantum correlation dynamics between two identical and spatially separated atoms in free space is investigated by the use of concurrence C and quantum discord (QD). The behaviors of QD differs in many unexpected ways from the entanglement in this system. Firstly, it shows the situations which the concurrence and QD can behave very differently with a “sudden birth” phenomenon of the former but not of the latter, and QD is only oscillating decays with time and the interqubit distance. We also verify the cases which QD is always greater than the concurrence and the region where the concurrence is vanished but with nonzero values for QD. Meanwhile an unexpected situation which the concurrence is greater than QD under the initial state |eg〉 is analyzed. It is revealed that the quantum correlation based only on QD is expected to be more robust than entanglement which is not suitable for all the initial states under the decoherence environment. Then, by introducing the incoherent pumping, we also study the different properties of the steady-state entanglement and QD about this atomic subsystem. It is shown that the incoherent pumping can overcome the decay of the atoms and the influences about the interqubit distance r 12/λ on the steady-state correlation can make the decay of the concurrence obviously quicker than QD, the life of the steady-state QD is evidently larger than the steady-state entanglement.

This paper presents a novel three-dimensional active frequency selective surfaces loading a varactor diode to achieve electrically controllable, by loading different values of paranoid voltage to control the variable capacitance diode. Simulation results show that the structure has excellent resonant characteristics in the range of 3.34GHz-1.59GHz, and has certain sensitivity for the change of the capacitance value,so it can achieve electrical controllable in the frequency band. The simulation results also show that this structure can satisfy characteristics for multiple perspectives in the whole plane, and be suitable to reduce radar cross section,when it is used on radomeofweapon systems in practical war.

By taking into account the intrinsic decoherence and the nonuniform magnetic field, quantum discord (QD) and steady quantum discord (SQD) behavior of a two-qubit anisotropic Heisenberg XYZ chain with different initial states are investigated. We find that properly tuning the external and self parameters not only can improve the quantum correlation and steady quantum correlation but also can weaken the effects of decoherence such as increasing anisotropic parameter Δ, decreasing B or b. When t is infinity, the SQD value and the physical about the SQD phenomenon are studied in detail, the SQD value is strongly dependent on the external and self parameters, which is increased evidently by increasing anisotropic parameter and decreasing nonuniform field. Through analyzing the physical about SQD phenomenon, the conditions about the existence of SQD phenomenon are analyzed with different initial states. These investigations can imply us more control parameters on quantum correlation and steady quantum correlation in solid state systems.

Lamelligomphus annakarlorum sp. nov. is described based on specimens collected from southern Yunnan Province, China (holotype male: Xishuangbanna National Nature Reserve, 21°57'59''N, 101°12'37''E, Xishuangbanna Dai Autonomous Prefecture, Yunnan Province, China). All type specimens of the new species have been deposited in the Collection of Aquatic Animals, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan City, Hubei Province, China. It is compared with Lamelligomphus camelus (Martin, 1904), which shares some similar characters.

In this paper, the modal analysis was carried out on the core and cavity of a 160KVA dry-type transformer based on the finite element analysis software of ANSYS. And the simulation results of the natural frequencies and modal shapes were obtained, which provided a theoretical guidance to the design of the transformer structure, and were meaningful to reduce the vibration and noise level of the transformer.

DC bias would cause the half-wave saturation of transformer, distortion of the exaction current, generation of high harmonic and the vibration and noise increases rapidly, which harm the safe operation of the transformers. In this paper, simulation of magnetic vibration and noise of a 160KVA dry-type transformer with DC bias and modal analysis with the finite element software comsol multiphysics is obtained. The software conduct multi-physical field coupling analysis to electric field, magnetic field, structural stress field and acoustic field, calculate the distribution of the noise and the natural frequency of transformer and propose effective measures to reduce the noise and vibration of transformer with DC bias.

The mistuning of periodic structure was generally considered to be natural parameter mistuning, such as stiffness mistuning, damping mistuning and mass mistuning. However, in engineering practice, there was another kind of mistuning——force mistuning, which has not been studied yet. Based on a typical concentrated parameter model of periodic structure, the vibration characteristics, such as natural characteristic, vibration mode and vibration localization of periodic structure with different mistuning forms, were compared and analyzed. The results show that, as a new mistuning form, force mistuning won’t bring mode localization, while it could lead to vibration response localization