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The lattice effect on the charge ordering in La1/3Sr2/3FeO3−δ is addressed by calcium ion substitution. Cation disorder effect due to size differences between A-site La3+, Sr2+, and Ca2+ has been found in La1/3(Sr1-xCax)2/3FeO3−δ perovskites. Below room temperature, a charge ordering transition has been detected by temperature dependent resistivity, differential scanning calorimeter, and mechanical spectroscopy. The charge ordering transition temperature TC shows a clear dependence on the variance of the A-site cation radius distribution. This result shows an important role of local lattice distortions on the charge ordering transition. As a comparison, octahedral titling transitions above room temperature were identified by mechanical spectroscopy, and the tilting transition temperatures are sensitive to the average cation radius. Finally, the implication of the cation disorder effect is discussed by a comparison of the case in manganates.

We present experimental studies on the spatial distribution of charged particles using a linearly polarized femtosecond laser interacting with a micro-structure target composed of micro-tube structure and planar foil. For protons, a six-lobed structure was observed in the low-energy region, while a smaller angular divergence was measured in the high-energy region. Electron distribution exhibits a circular distribution at low energies and double-lobed structure at high energies. These results are well reproduced by 3D particle-in-cell simulations, showing that the profile of electrons driven by a laser pulse is manipulated by the micro-tube structure, which maps into the spatial distribution of protons via a strong charge separation field. These results demonstrate the effect of micro-structures on laser-driven particle sources and provide a possible approach for spatial manipulation of the particle beams.

A biological enzyme – Laccase from Trametes versicolor (LacTv) – has been recognized as a highly efficient bifunctional catalyst in a rechargeable lithium–air battery system whose intrinsic pH change during discharge/charge can regulate the in situ recovery of the enzyme, making them an in situ synergistic match, enabling the battery to offer an extraordinarily flat discharge voltage of ∼3.75 V for 120 h, and remarkable durability (cycling steadily over 1100 h) with a narrow voltage gap of ∼0.24 V.

Multi-wavelength simultaneous observations are essential to the constraints on the origin of fast radio bursts (FRBs). However, it is a significant observational challenge due to the nature of FRBs as transients with a radio millisecond duration, which occur randomly in the sky regardless of time and position. Here, we report the search for short-time fast optical bursts in the GWAC archived data associated with FRB 20181130B, which were detected by the Five Hundred Meter Spherical Radio Telescope (FAST) and recently reported. No new credible sources were detected in all single GWAC images with an exposure time of 10 s, including image with coverage of the expected arrival time in optical wavelength by taking the high dispersion measurements into account. Our results provide a limiting magnitude of 15.43$\pm0.04$ mag in R band, corresponding to a flux density of 1.66 Jy or 8.35 mag in AB system by assuming that the duration of the optical band is similar to that of the radio band of about 10 ms. This limiting magnitude makes the spectral index of $\alpha, Comment: Accepted by ApJ

Earlier neutron scattering studies suggested the coexistence of complex stripelike and zigzaglike antiferromagnetic orders in polar honeycomb lattice ${\mathrm{Ni}}_{2}{\mathrm{Mo}}_{3}{\mathrm{O}}_{8}$, while its magnetoelectric (ME) behavior as an emergent effect is thus of high interest. Here we report our observations of two metamagnetic transitions and novel ME responses of ${\mathrm{Ni}}_{2}{\mathrm{Mo}}_{3}{\mathrm{O}}_{8}$ single crystals against high magnetic field $H$ up to \ensuremath{\sim}60 T. The $c$-axis (polar axis) spontaneous electric polarization ${P}_{\mathrm{spin}}$, emerging at the magnetic N\'eel temperature ${T}_{N}\ensuremath{\sim}5.5\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, and its remarkable response to $H$ applied along the $c$ axis ($H//c$) and $a$ axis ($H//a$), respectively, provide the clear evidence for the magnetism-driven ferroelectricity. While the magnetism exhibits the in-plane anisotropy to some extent, the magnetic field dependencies of magnetization and electric polarization in the low-field region and high-field region are distinctly different. In the low-field region where a weak spin-flop type metamagnetic transition occurs, the electric polarization response shows the parabolic dependence of magnetic field applied along both the $c$ axis and in-plane $a$ axis. The second metamagnetic transition happens when the magnetic field extends up to the high-field region where the magnetization and electric polarization response at low temperature are characterized by an extraordinarily broad plateau for the magnetic field along the $c$ axis but roughly linear dependence for field along the $a$ axis. These unusual phenomena are discussed, based on the symmetry-related local ME tensor analysis, and it is suggested that both the spin current and p-d hybridization mechanisms may contribute to the spontaneous electric polarization and ME responses. The present work demonstrates ${\mathrm{Ni}}_{2}{\mathrm{Mo}}_{3}{\mathrm{O}}_{8}$ as a unique multiferroic and promising platform for exploring the rich spin-1 physics and ME phenomena in honeycomb lattice.

The Ground Wide Angle Camera Network (GWAC-N) is a network of robotic multi-aperture, multiple field-of-view (FoV) optical telescopes. The main contingent of GWAC-N instruments are provided by the Ground Wide Angle Cameras Array (GWAC-A), and additional, narrower FoV telescopes are utilized to provide fast multi-band follow-up capabilities. The primary scientific goal of the GWAC-N is to search for optical counterparts of gamma-ray bursts that will be detected by the Space Variable Object Monitor (SVOM) satellite. The GWAC-N performs many additional observing tasks including follow-up of Target of Opportunities (ToO) targets and the detection (and monitoring) of variable objects and optical transients. To handle these use cases (and to allow for extensibility), we have designed ten observation modes and 175 observation strategies, including a joint strategy with multiple GWAC-N telescopes for the follow-up of gravitational wave (GW) events. To perform these observations, we develop an Automatic Observation Management (AOM) system capable of performing object management, dynamic scheduling, automatic broadcasting across the network, and image handling. The AOM system combines the individual telescopes which comprise the GWAC-N into a network and smoothly organizes all associated operations, completely meeting the requirements dictated by GWAC-N. With its modular design, the AOM is scientifically and technically viable for other general-purpose telescope networks. As the GWAC-N extends and evolves, the AOM will greatly enhance its discovery potential. In this first paper of a series, we present the scientific goals of the GWAC-N and detail the hardware, software, and workflow developed to achieve these goals. The structure, technical design, implementation, and performance of the AOM system are also described in detail. We conclude with a summary of the current status of the GWAC-N and our near-future development plan.

To analyze the difficulty, distinction and result of the first national public health practice skills competition among college students, it showed the general situation of this competition, and discussed the present situation, problems and countermeasures of skills training for students majoring in preventive medicine. Based on such competition, educators can promote teaching reform and post competency training.通过对首届全国大学生公共卫生实践技能大赛的试题难度、区分度以及比赛成绩等数据分析，揭示本次大赛的试题及比赛成绩概况，探讨预防医学专业学生的技能培养现状以及存在的问题和对策。依托公共卫生实践技能大赛，促进教学改革与岗位胜任力人才培养。.

The observation of the transient sky through a multitude of astrophysical messengers hasled to several scientific breakthroughs these last two decades thanks to the fast evolution ofthe observational techniques and strategies employed by the astronomers. Now, it requiresto be able to coordinate multi-wavelength and multi-messenger follow-up campaign withinstruments both in space and on ground jointly capable of scanning a large fraction of thesky with a high imaging cadency and duty cycle. In the optical domain, the key challengeof the wide field of view telescopes covering tens to hundreds of square degrees is to dealwith the detection, the identification and the classification of hundreds to thousands of opticaltransient (OT) candidates every night in a reasonable amount of time. In the last decade, newautomated tools based on machine learning approaches have been developed to perform thosetasks with a low computing time and a high classification efficiency. In this paper, we presentan efficient classification method using Convolutional Neural Networks (CNN) to discard anybogus falsely detected in astrophysical images in the optical domain. We designed this toolto improve the performances of the OT detection pipeline of the Ground Wide field AngleCameras (GWAC) telescopes, a network of robotic telescopes aiming at monitoring the opticaltransient sky down to R=16 with a 15 seconds imaging cadency. We applied our trainedCNN classifier on a sample of 1472 GWAC OT candidates detected by the real-time detectionpipeline. It yields a good classification performance with 94% of well classified event and afalse positive rate of 4%., 12 pages, 8 figures, 5 tables

Objective To evaluate the safety and efficacy of a new technique for accurate ostial/non-ostial coronary stenting in percutaneous coronary intervention (PCI). Background Accurate stent localization is a key factor impacting the postoperative success of patients undergoing PCI. However, the accurate localization of some lesions, especially ostial lesions, is very difficult to achieve, because they are often complicated by bobbing or to-and-fro movement of the stent during cardiac contractions. Methods We report a novel technique of precise ostial/non-ostial stenting based on the buddy balloon anchor stent (BBAS) technique. Between May 2014 and July 2017, 47 patients with significant ostial/non-ostial coronary stenosis that required accurate stenting were included in this study. Of them, 23 patients were treated using the conventional method and the remaining 24 patients were treated using (BBAS) technique. Evaluation was then performed using intravascular ultrasound (IVUS) in the procedural, or coronary computed tomography angiography (CCTA) in the follow up. Results Using the BBAS technique, the procedural success was achieved in all 24 (100%) cases. IVUS was performed in seven patients (29.17%) and no procedural complications occurred. All six failed cases that occurred among patients with right coronary artery and left anterior descending artery ostial stenosis treated using the conventional method, the lesions were subsequently successfully re-stented using the BBAS technique. After a follow-up of 3-36 months, CCTA was performed in 11 patients (45.83%), all the stents were in the accurate position. There were no major cardiovascular events of death, myocardial infarction, or target lesion revascularization. Conclusion BBAS is a simple, highly successful and safe technique for accurate stenting of difficult ostial/nonostial coronary stenosis lesions.

In this study, the impact and post-impact behavior of three-dimensional (3D) four-directional carbon/epoxy braided composites having different braiding angles were investigated. The same impact energy (45 J) was applied to the specimens. The post-impact mechanical properties of the materials were performed by compression after impact (CAI) testing, and the processes were monitored by the acoustic emission (AE) technique. Results showed that the specimens with larger braiding angle sustained higher peak loads, and smaller impact damage area, mainly attributed to a more compact space arrangement. The CAI strength and damage mechanism were found to be mainly dependent on the axial support of the braiding fiber tows. Increasing the braiding angle of the composites, the CAI strength was reduced, and the damage mode of the composites was changed from transverse fracture to shear one. Combining AE parameters and CAI curves allows one to characterize the failure process, thereby enabling fracture analysis of the materials under study.

The second observational campaign of gravitational waves organized by the LIGO/Virgo Collaborations has led to several breakthroughs such as the detection of gravitational wave signals from merger systems involving black holes or neutrons stars. During O2,14 gravitational wave alerts were sent to the astronomical community with sky regions covering mostly over hundreds of square degrees. Among them, 6 have been finally confirmed as real astrophysical events. Since 2013, a new set of ground-based robotic telescopes called GWAC and its pathfinder mini-GWAC have been developed to contribute to the various challenges of themulti-messenger and time domain astronomy. The GWAC system is built up in the framework of the ground-segment system of the SVOM mission that will be devoted to the study of the multi-wavelength transient sky in the next decade. During O2, only the mini-GWAC telescopenetwork was fully operational. Due to the wide field of view and fast automatic follow-up capabilities of the mini-GWAC telescopes, they were well adapted to efficiently cover the sky localization areas of the gravitational wave event candidates. In this paper, we present the mini-GWAC pipeline we have set up to respond to the GW alerts and we report our optical follow-up observations of 8 GW alerts detected during the O2 run. Our observations provided the largest coverage of the GW localization areas in a short latency made by any optical facility. We found tens of optical transient candidates in our images, but none of those could be securely associated with any confirmed black hole-black hole merger event. Based on this first experience and the near future technical improvements of our network system, we will be more competitive to detect the optical counterparts from some gravitational wave events that will be detected during the upcoming O3 run, especially those emerging from binary neutron star mergers., 17 pages, 10 figures, 11 tables

Objective To provide reference for further perfection and revision of standards relevant to limb injury by comparing the evaluation results of different disability standards of long bone fracture. Methods Thirty cases were selected from the long bone fracture cases accepted by our institution in 2018. These cases include 5 cases of shoulder, elbow, wrist, hip, knee, ankle joints, respectively, to investigate the degree of loss of function of joints after long bone fracture. Disability evaluation was made according to Classification of the Impairment Related To Injury （hereinafter referred to as Classification）, Assessment for Body Impairment of the injured in road traffic accidents （now repealed, hereinafter referred to as original Road Standard） and Identifying Work Ability-Gradation of Disability Caused by Work-related Injuries and Occupational Diseases （hereinafter referred to as Work Standard）. The disability evaluation results of every domestic standard were compared with the joint damage rate of Guides to the Evaluation of Permanent Impairment （hereinafter referred to as GEPI）. Results The functional loss rate of joints （except ankle） was 26%-48%，and the ankle functional loss rate was 51%-64%. The mean value of GEPI joint impairment rate of the joints was 13%-22%, with the fluctuation range less than 10%. The rate of level 10 disability was 100% according to the Classification. The rate of level 10 disability was 27%, the rate of level 9 disability was 6% and 67% were not disabled according to the original Road Standard. The rate of level 10 disability was 10% according to the Work Standard and 90% had a disability above level 10 （47% were classified as level 7 disability）. Conclusion The people with limb joint dysfunction in this study had evaluation results with a smaller fluctuation range and better consistency according to the Classification and GEPI. The evaluation results according to the original Road Standard and the Work Standard has a less consistency. The Classification is more similar to GEPI and is more reasonable.四肢长骨骨折不同伤残标准评定结果的比较.目的 通过比较四肢长骨骨折不同伤残标准的评定结果，为进一步完善和修订肢体损伤相关标准提供参考。 方法 选取本鉴定机构2018年受理的四肢长骨骨折案件30例，包括肩、肘、腕、髋、膝、踝关节各5例，分别统计四肢长骨骨折后遗关节功能丧失程度，并依照《人体损伤致残程度分级》（以下简称《分级》）、《道路交通事故受伤人员伤残评定》（已废止，以下简称“原《道标》”）、《劳动能力鉴定 职工工伤与职业病致残等级》（以下简称《工标》）进行伤残评定，参照《永久性残损评定指南》（Guides to the Evaluation of Permanent Impairment，GEPI）关节残损率，对国内各标准定残结果进行比较。 结果 四肢大关节（踝关节除外）功能丧失率为26%~48%、踝关节功能丧失率为51%~64%，对应GEPI的关节残损率均值为13%~22%，区间波动小于10%。《分级》评定为十级残疾的比例为100%。原《道标》评定为十级残疾的比例为27%，评定为九级残疾的比例为6%，未达残疾的比例为67%。《工标》评定为十级残疾的比例为10%，残疾等级高于十级的比例为90%（其中评定为七级残疾的比例为47%）。 结论 本研究的肢体关节功能障碍者，按照《分级》和GEPI评定伤残的结果波动范围小、一致性较好，而原《道标》和《工标》评定伤残的结果与GEPI一致性较差，说明《分级》与GEPI更接近、更合理。.法医学；骨折；标准；伤残评定；残疾等级；对比研究.

We report the detection and follow-up of a superstellar flare GWAC 181229A with an amplitude of ΔR ∼ 9.5 mag on an M9-type star by SVOM/GWAC and the dedicated follow-up telescopes. The estimated bolometric energy E bol is (5.56–9.25) × 1034 erg, which makes the event one of the most powerful flares seen on ultracool stars. The magnetic strength is inferred to be 3.6–4.7 kG. Thanks to sampling with a cadence of 15 s, a new component near the peak time with a very steep decay is detected in the R-band light curve, followed by the two-component flare template given by Davenport et al. An effective temperature of 5340 ± 40 K is measured by fitting a blackbody shape to the spectrum in the shallower phase during the flare. The filling factors of the flare are estimated to be ∼30% and 19% at the peak time and at 54 minutes after the first detection. The detection of this particular event with large amplitude, huge emitted energy, and a new component demonstrates that high-cadence sky monitoring cooperation with fast follow-up observations is very important for understanding the violent magnetic activity.

To reduce the acidity defect of 4,8-dihydrodifurazano[3,4-b,e]pyrazine(DFP), a new energetic ionic compound aminourea salt of 4,8-dihydrodifurazano[3,4-b,e]pyrazine (DSDFP) was designed and synthesized with a yield of 72.6%. The structure of target compound was characterized by means of NMR (1H and 13C), IR spectra, elemental analysis and single crystal X-ray diffraction. The thermal stability was tested by DSC and TG method and DSDFP shows good thermal stability with exothermic decomposition peaks in the range of 267.3 °C ∼ 282.3 °C. The impact sensitivity was measured using BAM standard method and the detonation performance was computed by Kamlet-Jacobs equations. Results show that DSDFP exhibits excellent impact sensitivity of greater than 40 J and desirable detonation performance with detonation velocity of 7891 m/s and detonation pressure of 27.1 GPa. These results highlight its great promise of potential candidates for high-performance energetic salt.

We report our photometric and spectroscopic follow-up observations of the superoutbursts of three dwarf novae (GWAC\,180415A, GWAC\,181017A and GWAC\,181211A) identified independently by the Ground Wide-angle Cameras system, one of the ground-based instruments of the China-France SVOM mission. Based on a combination of our photometry and that taken from the AAVSO, our period analysis of the superhumps enables us to determine the mass ratios to be 0.0967-0.1163, 0.1879-0.1883 and 0.0981-0.1173 for GWAC\,180415A, GWAC\,181017A and GWAC\,181211A, respectively. GWAC\,180415A can be firmly identified as a WZ sge-type dwarf novae due to its long duration ($\sim2$ weeks) multiple rebrightenings with amplitudes of 3-4 magnitudes, the early superhump associated with a double-wave modulation and the low mass ratio. The inferred low mass ratio and location in the $\varepsilon-P_{\mathrm{orb}}$ diagram suggest that GWAC\,181211A is a WZ sge-type dwarf novae candidate. The measured Balmer decrements suggest the Balmer line emission is produced from an optical thick region in GWAC\,180415A and GWAC\,181017A, and from an optical thin region in GWAC\,181211A.

Domain-wall conductivity (DWC) in ferroelectrics receives a lot of attention these days, as it involves a confined two-dimensional electron gas at room temperature, which seems promising for devices. This study finds that neighboring domain walls (DWs) in periodically-poled LiNbO${}_{3}$ exhibit opposite DWC behavior: A head-to-head configuration favors electron transport, while tail-to-tail inhibits it. This asymmetric conduction is quantified using a quantum-mechanical model that also accounts for the observed DW roughness. These findings allow tuning of DW-based electron gases in nanoelectronics, such as logic circuits, memory, or switching devices.

Cancer is the main leading cause of death in the world, although it has been made noteworthy advances in cancer research in the past decades. Early detection of cancer is extremely important in improving the chances of successful therapy. Thus, it is urgently needed to make further efforts to explore novel tumor markers for treatment. Nicotinamide N-methyltransferase (NNMT) is a cytosolic enzyme which catalyzes the N-methylation of nicotinamide to form 1-methylnicotinamide (1-MNA), and plays an important role in controlling the intracellular concentration of nicotinamide. Nicotinamide, the precursor to NAD+, is an important cofactor that associates cellular redox states with energy metabolism. Growing evidence shows that NNMT protein levels are elevated in a variety of human cancers, and increased NNMT expression has been linked to tumor aggressiveness. This paper presents a review for the role of NNMT expressed in a series of human cancers and the regulating mechanism involved, and offers its potential value of NNMT in cancer detection and treatment.

The electronic structure, magnetic exchange interactions, and spin-driven ferroelectricity in skyrmion host ${\mathrm{GaV}}_{4}{\mathrm{S}}_{8}$ have been studied on the basis of first-principles calculations and symmetry analysis. We find the reconstruction of band structure with the increasing value of Hubbard parameter U. The ferromagnetic ground state is determined by the symmetric exchange interaction along interplane bonds. The antisymmetric Dzyaloshinskii-Moriya interaction along intraplane bonds plays a major role in the origins of cycloidal and skyrmion phases. The exchange-striction mechanism is identified as the main origin of spin-driven polarization. Moreover, two spin-current mechanisms expressed by ${\mathbf{P}}_{1}\ensuremath{\propto}{\mathbf{r}}_{ab}\ifmmode\times\else\texttimes\fi{}({\mathbf{S}}_{a}\ifmmode\times\else\texttimes\fi{}{\mathbf{S}}_{b})$ and ${\mathbf{P}}_{2}\ensuremath{\propto}{\mathbf{S}}_{a}\ifmmode\times\else\texttimes\fi{}{\mathbf{S}}_{b}$ appear in the cycloid, while only the former mechanism appears in the skyrmion.

A high-efficiency extracellular electron transfer (EET) of exoelectrogens from the inside of the outer membrane to the external environment is of great importance in the bioelectrochemical energy research. In this regard, developing functional modifiers for individual bacteria, meanwhile integrating efficient light-enhanced energy conversion process possess huge potential to achieve excellent EET. Herein, a practical strategy of modifying individual bacteria by using photo-responsive N, S-doped carbon dots (m-NSCDs) is proposed. This suggested that the m-NSCDs can act as dual-functional modifiers which not only afford enhanced conductivity of bacteria, but also serve as photosensitizers to achieve light-enhanced catalytic process. Specifically, this novel design enables the simultaneous utilization of light- and electrochemical-energy, eventually yielding a superior power output performance.

To explore the effects of different fluid resuscitation regimens on oxygen metabolism during shock stage of burn injury in swine.Twelve Bama miniature swines were divided into crystal and colloid group (Group 1) and Parkland group (Group 2) according to the random number table. The swine models of burns shock were established. The fluid resuscitation was begun at post injury hour (PIH) 2 according to Chinese formulation or Parkland's formulation, respectively. The blood pressure, urine volume, heart rate, central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP) were recorded. The liquid volume was calculated at the first and second PIH 24. The changes in oxygen delivery (DO2), oxygen consumption (VO2), oxygen extraction (O2Ext) and D-lactate (D-LA) were determined before injury and at PIH 4, 8, 24, and 48. Statistical analyses were performed.There were no statistical differences between the two groups in blood pressure, urine volume, heart rate, CVP, PCWP in every interval (all P0.05). The resuscitation liquid volume in the two groups during the first and second PIH 24 conformed to the domestic consensus. The VO2 at PIH 8 was significantly higher than that of pre-burn in both groups [(190±29) vs (83±42) L·min(-1)·m(-2,) (149±33) vs (85±15) L·min(-1)·m(-2,) both P0.05], and the VO2 at PIH 8 was significantly higher in Group 1 than that in Group 2 (P0.05). The DO2 at PIH 24 in Group 1 was significantly lower than that in Group 2 [(686±72) vs (853±81) L·min(-1)·m(-2,) P0.05]. There were no significant differences between the two groups in O2Ext at any time points (all P0.05). The D-LA at PIH 8 was significantly higher in Group 1 than that in Group 2 [(53±4) vs (45±6) mmol/L, P0.05].There are no significant differences in the resuscitation effects of the crystal and colloid resuscitation regimen and Parkland's formulation on oxygen metabolism during shock stage of burn injury in swine.

Focal spot effects on the generation of proton beams are investigated by a high-intensity high-contrast laser irradiating on solid foil in target normal sheath acceleration experiments. Different spot size, transverse shape, and intensity of the laser are obtained by appropriately using deformable mirrors and parabolic mirrors. Experiments show that the maximum proton energy is mainly determined by the laser intensity if the focal spot size is not seriously changed. Compared with the previous experimental results, the optimum foil thickness d o is scaled by the laser intensity I as d o ~ I 0.33. The corresponding theoretical estimation is carried out as d o ~ I 0.25 for ultra-high intensity laser systems with similar contrast. MULTI and particle-in-cell simulations are used to interpret the experimental results.