Research on the Control Cover against Solenopsis invicta and Rapid Extinguishment of Its Epidemic

Based on the biological characteristics of Solenopsis invicta and the structural characteristics of its ant nest,a fast and efficient closed treatment device was developed.Compared with the simple chemical treatment commonly used at present,the developed treatment device(the ant nest control cover)is a fast and efficient method to exterminate S.invicta in 7 d,featured by short course,quick results and good effect.

浅析生猪养殖用地政策

文章介绍了近年来,国家出台的支持生猪生产发展的新政策及各地的经验和做法,分析了生猪养殖用地面临的新情况新问题,提出了一些合理化建议。

Gastroduodenal intussusception due to gastric schwannoma treated by billroth Ⅱ distal gastrectomy:One case report

Schwannomas are rarely observed in the gastrointestinal tract.The most common symptoms of a gastric schwannoma are abdominal pain or dyspepsia,gastrointestinal bleeding,and an abdominal mass.Many gastric schwannomas are asymptomatic and are discovered incidentally or at postmortem.The diagnosis of a schwannoma is based on immunohistochemical positivity for S-100 protein.Wepresent a case report of a rare complication of gastric schwannoma causing gastroduodenal intussusception that was successfully managed by a BillrothⅡdistal gastrectomy.In this rare case,the patient had intermittent,colicky abdominal pain,nausea,and vomiting for over 4wk accompanied by a weight loss.A diagnosis of gastric intussusception was made by computed tomography.A BillrothⅡdistal gastrectomy was then performed,and complete en bloc removal(R0 resection)was achieved.Pathology confirmed a gastric schwannoma through positive immunohistochemical staining for S-100 protein.

A Compact Ultra-Wideband Circularly Polarized Antenna Array for Vehicular Communications

In this paper,a new compact ultrawideband(UWB)circularly polarized(CP)antenna array for vehicular communications is proposed.The antenna array consists of a 2×2 sequentially rotated T-shaped cross dipole,four parasitic elements,and a feeding network.By loading the T-shaped cross dipoles with parasitic rectangular elements with cut corners,the bandwidth can be expanded.On this basis,the radiation pattern can be improved by the topology with sequential rotation of four T-shaped cross-dipole antennas,and the axial ratio(AR)bandwidth of the antenna also can be further enhanced.In addition,due to the special topology that the vertical arms of all Tshaped cross dipoles are all oriented toward the center of the antenna array,the gain of proposed antenna is improved while the size of the antenna is almost the same as the traditional cross dipole.Simulated and measured results show that the proposed antenna has good CP characteristics,an impedance bandwidth for S11<-10 d B of about 106.1%(3.26:1,1.57-5.12 GHz)and the 3-d B AR bandwidth of about 104.1%(3.17:1,1.57-4.98 GHz),a wide 3-d B gain bandwidth of 73.3%as well as the peak gain of 8.6 d Bic at 3.5 GHz.The overall size of antenna is 0.56λ×0.56λ×0.12λ(λrefers to the wavelength of the lowest operating frequency in free space).The good performance of this compact UWB CP antenna array is promising for applications in vehicular communications.

Propofol injection combined with bone marrow mesenchymal stem cell transplantation better improves electrophysiological function in the hindlimb of rats with spinal cord injury than monotherapy

The repair effects of bone marrow mesenchymal stem cell transplantation on nervous system damage are not satisfactory. Propofol has been shown to protect against spinal cord injury. Therefore, this study sought to explore the therapeutic effects of their combination on spinal cord injury. Rat models of spinal cord injury were established using the weight drop method. Rats were subjected to bone marrow mesenchymal stem cell transplantationvia tail vein injection and/or propofol injectionvia tail vein using an infusion pump. Four weeks after cell transplan-tation and/or propofol treatment, the cavity within the spinal cord was reduced. The numbers of PKH-26-positive cells and horseradish peroxidase-positive nerve ifbers apparently increased in the spinal cord. Latencies of somatosensory evoked potentials and motor evoked potentials in the hindlimb were noticeably shortened, amplitude was increased and hindlimb motor function was obviously improved. Moreover, the combined effects were better than cell transplantation or propofol injection alone. The above data suggest that the combination of propofol injection and bone marrow mesenchymal stem cell transplantation can effectively improve hindlimb electro-physiological function, promote the recovery of motor funtion, and play a neuroprotective role in spinal cord injury in rats.

Size and temperature effects on band gaps in periodic fluid-filled micropipes

A new model is proposed for determining the band gaps of flexural wave propagation in periodic fluid-filled micropipes with circular and square thin-wall cross-sectional shapes, which incorporates temperature, microstructure, and surface energy effects. The band gaps depend on the thin-wall cross-sectional shape, the microstructure and surface elastic material constants, the pipe wall thickness, the unit cell length, the volume fraction, the fluid velocity in the pipe, the temperature change,and the thermal expansion coefficient. A systematic parametric study is conducted to quantitatively illustrate these factors. The numerical results show that the band gap frequencies of the current non-classical model with both circular and square thin-wall cross-sectional shapes are always higher than those of the classical model. In addition,the band gap size and frequency decrease with the increase of the unit cell length according to all the cases. Moreover, the large band gaps can be obtained by tailoring these factors.

Improved Staggered Algorithm for Phase-Field Brittle Fracture with the Local Arc-Length Method

The local arc-length method is employed to control the incremental loading procedure for phase-field brittle fracture modeling.An improved staggered algorithm with energy and damage iterative tolerance convergence criteria is developed based on the residuals of displacement and phase-field.The improved staggered solution scheme is implemented in the commercial software ABAQUS with user-defined element subroutines.The layered system of finite elements is utilized to solve the coupled elastic displacement and phase-field fracture problem.A one-element benchmark test compared with the analytical solution was conducted to validate the feasibility and accuracy of the developed method.Our study shows that the result calculated with the developed method does not depend on the selected size of loading increments.The results of several numerical experiments show that the improved staggered algorithm is efficient for solving the more complex brittle fracture problems.

Parametric Structural Optimization of 2D Complex Shape Based on Isogeometric Analysis

The geometric model and the analysis model can be unified together through the isogeometric analysis method,which has potential to achieve seamless integration of CAD and CAE.Parametric design is a mainstream and successful method in CAD field.This method is not continued in simulation and optimization stage because of the model conversion in conventional optimization method based on the finite element analysis.So integration of the parametric modeling and the structural optimization by using isogeometric analysis is a natural and interesting issue.This paper proposed a method to realize a structural optimization of parametric complex shapes by using isogeometric analysis.By the given feature curves and the constraints,a feature frame model is built.Based on the feature frame model,a parametric representation of complex shape is obtained.After adding some auxiliary curves,the feature frame model is divided into many box-like patches in three dimension or four-sided patches in two dimension.These patches are built into parametric patches by using volume interpolation methods such as Coons method.Based on the parametric patches,isogeometic analysis is applied.Thus,the relationships are constructed among the size parameters,the control points and the physical performance parameters.Then the sensitivity matrix could be derived based on the relationships.The size optimization is carried out in the first stage by taking the size parameters as variables.Based on the result of size optimization,shape optimization with the constraints of stress is carried out in the second stage by taking the control points as variables.Serval planar complex shapes are taken as example to verify our method.The results verify that the parametric modeling and structural optimization can be united together without model conversion.Benefit from this,the optimization design can be executed as a dark box operation without considering the concrete modeling and analysis by input of the sizes,constraints and loads.

Bending and wave propagation analysis of axially functionally graded beams based on a reformulated strain gradient elasticity theory

A new size-dependent axially functionally graded(AFG) micro-beam model is established with the application of a reformulated strain gradient elasticity theory(RSGET). The new micro-beam model incorporates the strain gradient, velocity gradient,and couple stress effects, and accounts for the material variation along the axial direction of the two-component functionally graded beam. The governing equations and complete boundary conditions of the AFG beam are derived based on Hamilton's principle. The correctness of the current model is verified by comparing the static behavior results of the current model and the finite element model(FEM) at the micro-scale. The influence of material inhomogeneity and size effect on the static and dynamic responses of the AFG beam is studied. The numerical results show that the static and vibration responses predicted by the newly developed model are different from those based on the classical model at the micro-scale. The new model can be applied not only in the optimization of micro acoustic wave devices but also in the design of AFG micro-sensors and micro-actuators.

Visual Feedback Disturbance Rejection Control for an Amphibious Bionic Stingray Under Actuator Saturation

Dear Editor,This letter is concerned with visual feedback disturbance rejection control for an amphibious bionic stingray subject to actuator saturation with internal and external disturbances. A visual feedback control method is designed for a dynamic nonlinear system on yaw angle of the amphibious bionic stingray via a finite-time extended-stateobserver,which is proved to achieve finite-time stability via a Lyapunov method. Finally, simulation results verify the effectiveness on the visual feedback control method.

Numerical Investigation on Flow Pattern of Air-Oil with Different Viscosities Lubrication

In the present work, the performance of oil-air two-phase flow under different lubricant oils was investigated. The simulation method was applied to study the influence of the oil viscosity on the flow pattern, velocity distribution and Re number in oil-air lubrication by FLUENT software with VOF model to acquire the working performance of oil-air lubrication for high-speed ball bearing. This method was used to obtain the optimum lubrication conditions of high-speed ball bearing. The optimum operating conditions that produce the optimum flow pattern were provided. The optimum annular flow was obtained by PAO6 oil with the low viscosity. Reynolds number influences the fluid shape and distribution of oil and air in pipe. The annular flow can be formed when Reynolds number is an appropriate value. The velocity distribution of oil-air two-phase flow at outlet was also discussed by different oil viscosities. The simulating results show that due to the effect of the oil viscosity and flow pattern the velocity decreased and expanded gradually close to the pipe wall, and the velocity increased close to the central pipe. The simulation results provide the proposal for the design and operation of oil-air two-phase flow lubrication experiments in the present work. This work provides a useful method in designing oil-air lubrication with the optimum flow pattern and the optimum operating conditions.

A New Discovery of Mineralization as Subseafloor Hydrothermal Replacement in the Duddar Super-Large SEDEX Lead-Zinc Deposit in Pakistan

0 INTRODUCTION Sedimentary exhalative(SEDEX)lead-zinc deposit was traditionally considered as a result of submarine hydrothermal exhalation,including exhalative plume and brine pool models(Izanloo et al.,2022;Spinks et al.,2021;Maghfouri et al.,2020;Sangster,2020,2018;Huang et al.,2019;Rajabi et al.,2015;Goodfellow and Lydon,2007;Large et al.,2005,2001;Peng et al.,2000;Goodfellow et al.,1993;Figures 1a,1b).However,recognition of mineralization as subseafloor hydrothermal replacement in a few SEDEX deposits has challenged the traditional consideration(Magnall et al.,2023,2021,2020a,b;Hayward et al.,2021;Figure 1c).Researchers come to believe that subseafloor replacement rather than submarine exhalation is a dominant process for SEDEX mineralization,but this needs to be examined through more case studies.

W型肝脏悬吊技术在全腹腔镜下全胃切除术中的应用

目的探讨W型肝脏悬吊技术在全腹腔镜下全胃切除术中的应用。方法回顾性分析2023年1月至2024年4月复旦大学附属华山医院连续收治的64例行全腹腔镜下全胃切除术病例的临床资料,术中均采用W型肝脏悬吊技术,即使用prolene线通过缝合结合悬吊的方式在左肝下方(膈顶与肝胃韧带之间)形成一个"W形"的网状结构以阻挡肝脏,观察患者术中情况及术后恢复情况。结果术中肝外叶及肝圆韧带悬吊效果理想,术区显露效果良好。手术时间为(140.9±33.2)min,肝脏悬吊时间为(2.7±0.2)min,术中失血(34.6±14.1)ml,术后住院(7.6±3.7)d。21例术后第1天肝功能指标升高,第3天开始明显下降;其中有6例术后第5天肝功能指标仍然升高,其余58例术后第5天肝功能指标均处于正常范围。无肝脏悬吊相关并发症发生。结论W型肝脏悬吊技术安全可行,不仅可以有效悬吊肝脏及肝圆韧带,还可以牵引扩大食管裂孔,或有助于迷走神经肝支的保护、降低下纵隔的手术操作及食管空肠吻合的难度。

Adversarial Defense Technology for Small Infrared Targets

With the rapid development of deep learning-based detection algorithms,deep learning is widely used in the field of infrared small target detection.However,well-designed adversarial samples can fool human visual perception,directly causing a serious decline in the detection quality of the recognition model.In this paper,an adversarial defense technology for small infrared targets is proposed to improve model robustness.The adversarial samples with strong migration can not only improve the generalization of defense technology,but also save the training cost.Therefore,this study adopts the concept of maximizing multidimensional feature distortion,applying noise to clean samples to serve as subsequent training samples.On this basis,this study proposes an inverse perturbation elimination method based on Generative Adversarial Networks(GAN)to realize the adversarial defense,and design the generator and discriminator for infrared small targets,aiming to make both of them compete with each other to continuously improve the performance of the model,find out the commonalities and differences between the adversarial samples and the original samples.Through experimental verification,our defense algorithm is not only able to cope with multiple attacks but also performs well on different recognition models compared to commonly used defense algorithms,making it a plug-and-play efficient adversarial defense technique.

我国牧草种质资源保护工作进展与发展思路

该文从我国牧草种质资源保护发展历史、主要工作内容以及现阶段工作进展3方面介绍了我国牧草种质资源保护工作概况,以期让更多人了解和参与到牧草种质资源保护和良种繁育工作中来。同时,从收集策略、如何用好现有资源和资源共享三方面对今后的牧草保种工作提出建议,旨在为相关工作提供参考。

Synthesis and adsorption performance of lead ion-imprinted micro-beads with combination of two functional monomers

A novel ion-imprinted polymer, lead ion-imprinted micro-beads with combination of two functional monomers, was synthesized using the W/O/W polymerization method. Two functional monomers, 1,12-dodecanediol-O,O’-diphenyl-phosphonic acid （DDDPA） and 4-vinylpyridine, were used to form a suitable construction with micro-pores fitting the template and recognition sites. The eflects of adsorbent dosage, solution pH and the competitive ions on the adsorption and separation eflciency of lead ions were investigated. The lead ion-imprinted micro-beads were eflcient for lead ions removal from aqueous solution in a broad pH range （4–9）, when the adsorbent dosage was above 0.1 g/L. The adsorption process obeyed the pseudo second-order kinetics model and it only took half an hour to reach the equilibrium. The adsorption isotherm of lead ion was described by the Langmuir model （R2 0.99） with a maximum adsorption capacity of 116.9 mg/g. In the presence of competitive ions Co2＋ and Cd2＋, the lead ion-imprinted micro-beads showed a high selectivity for lead ions. The selectivity coeficient of Pb2＋/Cd2＋ and Pb2＋/Co2＋are 99.3 and 114.7, respectively.

简谐力激励下结构的生长式拓扑优化方法（英文）

目的:振动在机械结构的工作中难以避免,且会显著降低机械结构的工作性能。因此,结构动力响应优化设计就显得尤为重要。本文旨在提出一种有效的简谐力激励下的结构拓扑优化方法,通过合理设计结构内加强筋的布局,减小结构特定位置处的位移响应幅值,提高结构的固有频率。概要:植物叶脉可以有效地支撑叶片以抵抗自然界中的风载。本文将植物叶脉分叉构型的最优性用于简谐力激励下结构的加强筋布局设计。首先对简谐力激励下结构的位移响应进行分析。在此基础上,构建以最小化结构特定位置处位移响应幅值为目标的生长式拓扑优化模型。然后,从数学优化的角度,分析加强筋的生长应遵循的规律,提出生长式拓扑优化的数值实现算法。最后通过数值算例证明了本文所提方法的有效性。

Prediction of electrical contact endurance subject to micro-slip wear using friction energy dissipation approach

Fretting wear is a common cause of failure of an electrical contact(EC). In this study, we analyzed in detail the failure of EC induced especially by sliding using the representative electrical terminals. Furthermore, combining the friction energy dissipation theory, we proposed a prediction model to evaluate the electrical connector endurance(ECE) based on the contact stress and geometrical changes during the wear process obtained from a numerical model. The study helps establish that the friction energy dissipation theory is a powerful tool to analyze a contact failure due to wear. The proposed model proves to be effective in predicting the ECE for all considered cases such as micro-slip amplitude, contact force, overturning angle, superficial layer thickness, and friction/wear coefficients.

The roles of active species in photo-decomposition of organic compounds by microwave powered electrodeless discharge lamps

Knowledge of the effective radiation spectrum irradiating substrates from microwave powered electrodeless discharge lamps（MEDLs）, and the active species that directly oxidize substrates in the photolytic process, is fragmentary and unclear. In this work, we conducted a comparative study using MEDLs made with quartz envelopes（MEDL-quartz） and with borosilicate Pyrex envelopes（MEDL-Pyrex） targeting the degradation of Rhodamine B（Rh B）via radical-extinguishing tests. We found that UVC/UVB radiation is essential to generate·OH and H2O2 in the MEDL-quartz system. The degradation of Rh B mostly originates from·OH species, which account for a contribution of 53.8%, while the remaining contribution is attributed to oxidation by H2O2 and direct photolysis. This degradation is influenced by several parameters. Acidic and neutral p Hs, but not extreme alkaline p H, benefit the degradation. To ensure a high intensity of UVC/UVB, the optimum ratio of the MEDL volume to the aqueous solution volume（VL/VS） is 0.4. Concentrations of 0.15-0.20 mmol/L of Rh B are suitable to obtain an effective quantum absorbance in the MEDL-quartz system,showing a high decomposition rate of 5.6 × 10^-3（mmol/L）min-1. Moreover, two other substrates, Reactive Brilliant Red X-3B and Safranine T, were tested and found to be efficiently degraded in the MEDL-quartz system.

绿脓杆菌对鲎素耐受性特点及耐受性机制的研究

【目的】为了探讨鲎素作为抗菌药物在临床使用中的安全性问题,通过鲎素连续增高浓度法对绿脓杆菌进行耐受性诱导,并对其耐受性机制进行初步研究,以期为鲎素的广泛应用提供理论依据。【方法】绿脓杆菌ATCC27853为试验菌株,通过连续增高浓度诱导法筛选抗药菌株,并通过抗药稳定性、交叉抗药性、抗药性代偿测定来探究其耐受性特点,通过对其胞外蛋白酶活性、生物膜形成、胞外多糖含量的变化来探讨其抗药性机制。【结果】通过连续增高鲎素浓度法对原始菌株进行30多代诱导后,绿脓杆菌ATCC27853对鲎素的MIC值逐渐增高,80多代时产生了明显抗药性。抗药菌株对丁胺卡那以及pexiganan、鲎素同源肽tachyplesin III、polyphemusin I均能产生不同程度的抗药性。在无药培养基中抗药菌株以更长的延滞期作为抗药性代偿,但在有药培养基中具有更短的延滞期和更大的生长速率。抗药菌株较原始菌株分泌的胞外蛋白酶活性增高,并能降低鲎素的抗菌活性。在同样条件下抗药菌株较原始菌株胞外多糖含量增高,更易形成生物膜。【结论】在长期选择压力下绿脓杆菌ATCC27853对鲎素能产生抗药性,其抗药性机制可能与生物膜形成、胞外蛋白酶失活鲎素有关。关于细菌对鲎素的抗药性机制,有待进一步研究。