Simulation of magnetization process and Faraday effect of magnetic bilayer films

We described ferromagnetic film and bilayer films composed of two ferromagnetic layers coupled through antiferromagnetic interfacial interaction by classical Heisenberg model and simulated their magnetization state,magnetic permeability,and Faraday effect at zero and finite temperature by using the Landau–Lifshitz–Gilbert(LLG)equation.The results indicate that in a microwave field with positive circular polarization,the ferromagnetic film has one resonance peak while the bilayer film has two resonance peaks.However,the resonance peak disappears in ferromagnetic film,and only one resonance peak emerges in bilayer film in the negative circularly polarized microwave field.When the microwave field’s frequency exceeds the film’s resonance frequency,the Faraday rotation angle of the ferromagnetic film is the greatest,and it decreases when the thickness of the two halves of the bilayer is reduced.When the microwave field’s frequency remains constant,the Faraday rotation angle fluctuates with temperature in the same manner as spontaneous magnetization does.When a DC magnetic field is applied in the direction of the anisotropic axis of the film,the Faraday rotation angle varies with the DC magnetic field and shows a similar shape of the hysteresis loop.

NiO/β-Ga_(2)O_(3)heterojunction diodes with ultra-low leakage current below 10^(-10)A and high thermostability

The 10 nm p-NiO thin film is prepared by thermal oxidation of Ni onβ-Ga_(2)O_(3)to form NiO/β-Ga_(2)O_(3)p-n heterojunction diodes(HJDs).The NiO/β-Ga_(2)O_(3)HJDs exhibit excellent electrostatic properties,with a high breakdown voltage of 465 V,a specific on-resistance(Ron,sp)of 3.39 mΩ·cm^(2),and a turn-on voltage(V on)of 1.85 V,yielding a static Baliga's figure of merit(FOM)of 256 MW/cm^(2).Also,the HJDs have a low turn-on voltage,which reduces conduction loss dramatically,and a rectification ratio of up to 108.Meanwhile,the HJDs'reverse leakage current is essentially unaffected at temperatures below 170?C,and their leakage level may be controlled below 10^(-10)A.This indicates that p-NiO/β-Ga_(2)O_(3)HJDs with good thermal stability and high-temperature operating ability can be a good option for high-performanceβ-Ga_(2)O_(3)power devices.

Cutting Experiment of Fraxinus mandshurica UsingWaterjet-Assisted CO_(2)Laser

High-quality wood products and valuable wood crafts receive everyone’s favor with the rapid development of the economy.In order to improve the cutting surface quality of wood forming parts,the cutting experiment of renewable Fraxinus mandshurica was conducted by waterjet-assisted CO_(2)laser(WACL)technology.A quadratic mathematical model for describing the relationship between surface roughness changes and cutting parameters was established.The effects of cutting speed,flow pressure and laser power on the kerf surface roughness of Fraxinus mandshurica when cutting transversally were discussed by response surface method.The experimental results showed that kerf surface roughness decreased under a lower laser power,higher cutting speed and higher flow pressure.When the cutting speed was 30 mm/s,flow pressure was 1.58 MPa and laser power was 45 W,the actual surface roughness of the optimized Fraxinus mandshurica was 2.41μm,and it was in accord with the theoretically predicted surface roughness value of 2.54μm,so the model fitted the actual situation well.Through the analysis of 3D profile morphology and micromorphology,it was concluded that the optimized kerf surface of Fraxinus mandshurica was smoother,the cell wall was not destroyed and the tracheid was clear.It provides the theoretical basis for wood micromachining.

Optimal Injection Attack for UCPS Under Vertical Depth-Keeping Task Via Game Approach

Dear Editor, This letter concerns about the security problem of underwater cyber-physical system(UCPS) for depth-keeping task in the vertical plane. A dynamic parametric model of the UCPS with ocean currents and hydrostatic is considered. With the intelligence of the controller, the objective function of a zero-sum game between the attacker and the controller is introduced. The attacker destroys the depth-keeping task of UCPS by injecting the designed false data into the system.

蜂针治疗过敏性鼻炎患者的疗效分析及免疫学指标变化

目的分析过敏性鼻炎患者应用蜂针治疗的效果,并分析其对免疫学指标的影响。方法回顾性分析2017年6月—2019年6月在广州医科大学附属第五医院治疗的80例过敏鼻炎患者的临床资料,按疗法分为对照组和观察组,每组40例。对照组行常规西药治疗,观察组行蜂针治疗。对比两组治疗前后的症状、免疫学指标、生活质量改善情况。结果观察组治疗前后鼻炎伴随症状总评价表评分、鼻症状评分的差值均大于对照组(P<0.05)。观察组治疗前后血清免疫球蛋白E、γ干扰素、白细胞介素4、白细胞介素6的差值均大于对照组(P<0.05)。观察组治疗前后鼻结膜炎生存质量调查问卷评分的差值均大于对照组(P<0.05)。结论蜂针可有效缓解过敏性鼻炎症状,增强免疫力,提高生活质量,可在临床推广应用。

T-PBFT: An EigenTrust-Based Practical Byzantine Fault Tolerance Consensus Algorithm

Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniques of blockchain directly affects the scalability of blockchain systems. Existing probabilistic finality blockchain consensus algorithms such as PoW, PoS, suffer from power consumptions and low efficiency;while absolute finality blockchain consensus algorithms such as PBFT, HoneyBadgerBFT, could not meet the scalability requirement in a largescale network. In this paper, we propose a novel optimized practical Byzantine fault tolerance consensus algorithm based on EigenTrust model, namely T-PBFT, which is a multi-stage consensus algorithm. It evaluates node trust by the transactions between nodes so that the high quality of nodes in the network will be selected to construct a consensus group. To reduce the probability of view change, we propose to replace a single primary node with a primary group. By group signature and mutual supervision, we can enhance the robustness of the primary group further. Finally, we analyze T-PBFT and compare it with the other Byzantine fault tolerant consensus algorithms. Theoretical analysis shows that our T-PBFT can optimize the Byzantine fault-tolerant rate,reduce the probability of view change and communication complexity.

RTRC:A Reputation-Based Incentive Game Model for Trustworthy Crowdsourcing Service

The ubiquity of mobile devices have promoted the prosperity of mobile crowd systems, which recruit crowds to contribute their resources for performing tasks. Yet, due to the various resource consumption, the crowds may be reluctant to join and contribute information. Thus, the low participation level of crowds will be a hurdle that prevents the adoption of crowdsourcing. A critical challenge for these systems is how to design a proper mechanism such that the crowds spontaneously act as suppliers to contribute accurate information. Most of existing mechanisms ignore either the honesty of crowds or requesters respectively. In this paper, considering the honesty of both, we propose a game-based incentive mechanism, namely RTRC, to stimulate the crowds to contribute accurate information and to motivate the requesters to return accurate feedbacks. In addition, an evolutionary game is designed to model the dynamic of user-strategy selection. Specially, the replicator dynamic is applied to model the adaptation of strategy interactions taking into account the dynamic nature in time dependence and we also derive the evolutionarily stable strategies(ESSs) for users. Finally, empirical results over the simulations show that all the requesters and suppliers will select honest strategy to maximize their profit.

Flow characteristics of natural circulation in a lead–bismuth eutectic loop

Lead and lead-alloys are proposed in future advanced nuclear system as coolant and spallation target.To test the natural circulation and gas-lift and obtain thermal-hydraulics data for computational fluid dynamics(CFD) and system code validation, a lead–bismuth eutectic rectangular loop, the KYLIN-Ⅱ Thermal Hydraulic natural circulation test loop, has been designed and constructed by the FDS team. In this paper, theoretical analysis on natural circulation thermal-hydraulic performance is described and the steady-state natural circulation experiment is performed. The results indicated that the natural circulation capability depends on the loop resistance and the temperature and center height differences between the hot and cold legs. The theoretical analysis results agree well with,while the CFD deviate from, the experimental results.

Variation Laws and Influencing Factors of pH in Fishery Waters in Quzhou City

[Objectives] This study was conducted to strengthen the understanding of the variation laws of pH in fishery waters. [Methods]Based on the investigation data of pH, dissolved oxygen(Do), water temperature(T) and chlorophyll a(Chl. a) of the fishery waters in Quzhou City from 2017 to 2020, the seasonal variation characteristics and influencing factors of pH in the fishery waters were analyzed and discussed. [Results] The pH of the fishery waters in Quzhou City was in the range of 6.40-11.3, and was characterized by the highest seasonal variation in spring and the lowest in winter. The correlation analysis showed that water temperature and pH were significantly positively correlated in spring and summer(P<0.05), and the photosynthesis of phytoplankton was the main reason that affected the pH of water bodies in spring and summer. There was a negative correlation between water temperature and pH in winter, and the pH in the natural waters had a significant negative correlation with water temperature(P<0.05). The balance of carbonate system in the water bodies was the main reason that affected the pH of water in winter. The level of water eutrophication(Chl. a) affected the pH of fishery waters to a certain extent. When Chl. a<10 μg/L, there was a significant positive correlation between the pH of fishery waters and Chl. a(P<0.05). Various environmental factors had different effects on the pH of different types of fishery waters. The stepwise regression analysis showed that the pH of natural waters was mainly affected by Chl. a, and the pH of aquaculture waters was mainly affected by water temperature and dissolved oxygen. [Conclusions]This study provides certain theoretical support for actual production management.

腔镜切割荷包吻合器在腹腔镜结直肠癌手术中的应用体会

目的结直肠手术中进行腔镜下荷包缝合一直是手术操作的难点,尤其是经自然腔道取标本手术(NOSES)。同时结肠、直肠吻合口处形成的“危险三角区”又是增加吻合口漏的主要因素。腔镜切割荷包吻合器的临床应用可以有效解决上述技术难题。方法本研究纳入5例行根治性手术的结直肠癌患者,包括4例直肠癌和1例乙状结肠癌。所有患者手术消化道重建过程中,乙状结肠荷包缝合及抵钉座固定步骤均使用腔镜切割荷包吻合器。结果患者平均年龄为(54.4±8.6)岁,患者平均BMI为(24.7±2.9)kg/m^(2)。4例患者行腹腔镜直肠癌根治+预防性末端回肠双腔造口术,1例患者行NOSES Ⅳ式。平均手术时间为(123.60±15.37)min,平均术中出血量为(98±36)mL,平均术后住院天数为(9.4±0.5)天。所有患者围术期均未出现并发症。结论腔镜直线荷包缝合器降低了全腔镜下乙状结肠与直肠消化道重建的操作难度。该设备的临床应用无论是对于常规腹腔镜手术,亦或是NOSES手术,都具有很好的临床价值与推广潜力。

Construction and Identification of Intestine-specific Expression Vector of Xylanase Gene(XynB)

The Aspergillus niger XynB gene and core promoter region of porcine RELMβgene were cloned into pcDNA3.1(-),and an intestine-specific expression vector pcDNA3.1-RELMβ-XynB-Myc-GFP carrying green fluorescence and Myc double tags was constructed.The vector was transfected into human colon cancer cells(HT29)and human liver cancer cells(Bel7402)using liposomes.Fluorescence microscopy revealed that the vector could specifically express green fluorescent protein(GFP)in HT29 cells.RT-PCR and Western Blot were performed on the HT29 cells transfected with the expression vector,and the results showed that the XynB gene was normally transcribed in HT29 cells,and the target protein expression was detected in the cells.

Non-drug interventions for cancer-related fatigue: an updated review

Non-drug interventions are easy operation, no damage and with significant effects treatment for cancer-related fatigue, which also can reduce the economic burden of cancer patients and improve the quality of life. This article reviews the effects of non-drug interventions on cancer-induced fatigue including exercise intervention, long distance healthy education, cognitive behavior intervention, traditional Chinese medicine intervention and emotional intervention to provide reference for clinical medical staff and relevant scholars.

Research progress on the application of Watson’s Human Caring Theory

This paper reviews the basic content,significance and application status of Watson's human caring theory in clinical departments,aiming to provide references for future research of relevant scholars in this field.In particular,Watson believes that human care is the essence of care,it is the combination of nurse science and human knowledge and the interaction between nurses and patients.

Demixing microwave signals using system-on-chip photonic processor

The integrated photonic processor,co-packaged with electronic peripherals,is proposed for blind source separation of microwave signals,which separates signal-of-interest from dynamic interference with real-time adaptability.

Rational construction of genome-minimized Streptomyces host for the expression of secondary metabolite gene clusters

Streptomyces offer a wealth of naturally occurring compounds with diverse structures,many of which possess significant pharmaceutical values.However,new product exploration and increased yield of specific compounds in Streptomyces have been technically challenging due to their slow growth rate,complex culture conditions and intricate genetic backgrounds.In this study,we screened dozens of Streptomyces strains inhabiting in a plant rhizosphere for fast-growing candidates,and further employed CRISPR/Cas-based engineering techniques for stepwise refinement of a particular strain,Streptomyces sp.A-14 that harbors a 7.47 Mb genome.After strategic removal of nonessential genomic regions and most gene clusters,we reduced its genome size to 6.13 Mb,while preserving its growth rate to the greatest extent.We further demonstrated that cleaner metabolic background of this engineered strain was well suited for the expression and characterization of heterologous gene clusters,including the biosynthetic pathways of actinorhodin and polycyclic tetramate macrolactams.Moreover,this streamlined genome is anticipated to facilitate directing the metabolic flux towards the production of desired compounds and increasing their yields.

Super-resolution diffractive neural network for alloptical direction of arrival estimation beyond diffraction limits

Wireless sensing of the wave propagation direction from radio sources lays the foundation for communication,radar,navigation,etc.However,the existing signal processing paradigm for the direction of arrival estimation requires the radio frequency electronic circuit to demodulate and sample the multichannel baseband signals followed by a complicated computing process,which places the fundamental limit on its sensing speed and energy efficiency.Here,we propose the super-resolution diffractive neural networks(S-DNN)to process electromagnetic(EM)waves directly for the DOA estimation at the speed of light.The multilayer meta-structures of S-DNN generate super-oscillatory angular responses in local angular regions that can perform the all-optical DOA estimation with angular resolutions beyond the diffraction limit.The spatial-temporal multiplexing of passive and reconfigurable S-DNNs is utilized to achieve high-resolution DOA estimation over a wide field of view.The S-DNN is validated for the DOA estimation of multiple radio sources over 5 GHz frequency bandwidth with estimation latency over two to four orders of magnitude lower than the state-of-the-art commercial devices in principle.The results achieve the angular resolution over an order of magnitude,experimentally demonstrated with four times,higher than diffraction-limited resolution.We also apply S-DNN’s edge computing capability,assisted by reconfigurable intelligent surfaces,for extremely low-latency integrated sensing and communication with low power consumption.Our work is a significant step towards utilizing photonic computing processors to facilitate various wireless sensing and communication tasks with advantages in both computing paradigms and performance over electronic computing.

Progress toward the sustainable development of world cultural heritage sites facing land-cover changes

The quantification of the extent and dynamics of land-use changes is a key metric employed to assess the progress toward several Sustainable Development Goals(SDGs)that form part of the United Nations 2030 Sustainable Development Agenda.In terms of anthropogenic factors threatening the conservation of heritage properties,such a metric aids in the assessment of achievements toward heritage sustainability solving the problem of insufficient data availability.Therefore,in this study,589 cultural World Heritage List(WHL)properties from 115 countries were analyzed,encompassing globally distributed and statistically significant samples of“monuments and groups of buildings”(73.2%),“sites”(19.3%),and“cultural landscapes”(7.5%).Land-cover changes in the WHL properties between 2015 and 2020 were automatically extracted from big data collections of high-resolution satellite imagery accessed via Google Earth Engine using intelligent remote sensing classification.Sustainability indexes(SIs)were estimated for the protection zones of each property,and the results were employed,for the first time,to assess the progress of each country toward SDG Target 11.4.Despite the apparent advances in SIs(10.4%),most countries either exhibited steady(20.0%)or declining(69.6%)SIs due to limited cultural investigations and enhanced negative anthropogenic disturbances.This study confirms that land-cover changes are among serious threats for heritage conservation,with heritage in some countries wherein the need to address this threat is most crucial,and the proposed spatiotemporal monitoring approach is recommended.

Optimal injection attack strategy for cyber-physical systems:a dynamic feedback approach

This paper investigates the system security problem of cyber-physical systems(CPSs),which is not only more practical but also more significant to deal with than the detecting faults problem.The purpose of this paper is to find an optimal attack strat-egy that maximizes the output error of the attacked system with low energy consumption.Based on a general model of linear time-invariant systems and a key technical lemma,a new optimal attack strategy for the meticulously designed false data injection attack is constructed.It is worth mentioning that compared with the existing model-based attack strategies,the designed one is more general and the corresponding attack strategy is more easily implemented when system states and external input are inaccessible.Key to overcom-ing the inaccessible information,a dynamic observer in the form of Luenberger is constructed.Finally,a networked magnetic levitation steel ball movement system is applied to illustrate the effectiveness of the proposed scheme.

Choroidal infarction after internal carotid artery stenting

Dear Editor,We present a case of choroidal infarction along with retinal infarction after carotid artery stenting(CAS),which is a rare condition not reported in the literature.CAS has increasingly been accepted as the mainstay reconstruction method for carotid artery stenosis compared with carotid endarterectomy(CEA)due to no need for general anesthesia.