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In order to clarify the occurrence of Solenopsis invicta in Quanzhou area and screen out the effective prevention and control agents suitable for the local Solenopsis invicta, the field control effects of 1% thiamethoxam amine granules, 1.8% abamectin cream, 0.05% indoxacarb bait and 5% rotenone soluble concentrate on the red fire ants were determined by investigating the habitat environment, living habits and transmission routes of the local Solenopsis invicta, in order to screen the best prevention and control agents. The results showed that the Solenopsis invicta in Quanzhou area were mainly distributed in the grassland (lawn), nursery, park, farmland, orchard and green belt, of which the suitable active temperature was 19-32°C. And they had mixed feeding distance habits, strong adaptability and various modes of spreading and diffusion. The field pharmacodynamic test showed that 1% thiamethoxam amine granules and 0.05% indoxacarb bait had good quick-acting property and durable effect on the active ant nests and active ergates. Although the 5% rotenone soluble concentrate had slightly slow quick-acting property, it had good persistence, while the quick-acting property and durable effect of 1.8% abamectin cream were both poor. Therefore, 1% thiamethoxam amine granules, 0.05% indoxacarb bait and 5% rotenone soluble concentrate were suitable for being promoted and applicated in the field. The results of this study could provide technical support and scientific basis for formulating the targeted prevention and control measures. [ABSTRACT FROM AUTHOR]

Biomass is an excellent carbon source with abundant production, wide variety, low price and environmentally friendly, and the preparation of carbon catalytic material from biomass is undoubtedly turning waste into treasure, which can fundamentally solve the problems of environmental pollution and resource waste. This paper introduces the effects of biomass species, components and structure on the performance of biomass carbon-based catalytic materials, compares the two common methods of pyrolysis and hydrothermal carbonization for the preparation of biomass carbon-based catalytic materials, discusses the three ways to further enhance the catalyst activity, heteroatom doping, metal-ion modification, and functionalization, and analyzes and summarizes the challenges faced by biomass carbon-based catalytic materials. [ABSTRACT FROM AUTHOR]

The experiment aimed to investigate the impact of plastic film mulching on the soil physicochemical properties and spring maize yield in the wind and sand erosion area of northern Shaanxi. The experiment utilized the locally recommended maize variety ZHONGYU968 and included three treatments: Surface mulching, inter-row mulching, and no mulching. The study analyzed the influence of mulching on the soil moisture content, pH value, organic matter, maize agronomic traits, yield, and grain nutritional quality. The results showed that in the 0-20 cm and 21-40 cm soil layers, the soil moisture content of the inter-row mulching treatment was higher than that of the no mulching treatment (P<0.05). In the 41-60 cm soil layer, both surface and inter-row mulching increased soil moisture content compared to no mulching (P<0.05). With the increase of soil depth, the pH value of all treatments exhibited a decreasing trend, with the pH values ranking as no mulching > inter-row mulching > surface mulching in different soil layers. Specifically, in the 0-20 cm soil layer, the pH value of surface mulching was lower than that of no mulching (P<0.05). In the 0-20 cm soil layer, the organic matter content of both inter-row and surface mulching was higher than that of no mulching (P<0.05), while in the 41-60 cm soil layer, the organic matter content of inter-row mulching was higher than that of surface mulching and no mulching (P<0.05). Maize under the inter-row mulching exhibited greater plant height, fresh ear weight, ear grain number, and yield than other treatments (P<0.05), with stem diameter and hundred-grain weight higher than no mulching (P<0.05). The crude protein and crude fat content of maize grains under inter-row mulching were 8.22% and 4.58%, The study indicates that the inter-row mulching is more suitable for spring maize cultivation in the wind and sand erosion area of northern Shaanxi and can be further promoted in the region. [ABSTRACT FROM AUTHOR]

The study was to investigate the modulatory effect of Sophora subprosrate polysaccharide (SSP) on inflammatory reaction and immunosuppression in PCV2-infected RAW264.7 cells. The PCV2-infected RAW264.7 cells were treated with SSP (100, 200 and 400 mg/L) for 16 h, the mRNA expression of signal transducer and activator of transcription 1, 2 ( STAT1, STAT2), janus kinase 1 (JAK1), tyrosine kinase 2 (TYK2), chemokine (C-C motif) ligand 3 (Ccl3), chemokine (C-X-C motif) ligand 2 (CXCL2), tumor necrosis factor alpha ( TNF-α), REL proto-oncogene, NF-κB subunit (Rel), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha and delta (Nfκbia, Nfκbid), and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor zeta (Nfκbiz) were measured. The protein expression levels of phospho-signal transducer and activator of transcription 1 and 2 (p-Stat1, p-Stat2), signal transducer and activator of transcription 1 and 2 (Stat1, Stat2), inhibitor of nuclear factor κB kinase subunit beta (IκB), phospho-inhibitor of nuclear factor κB kinase subunit beta (p-Iκ B), nuclear factor NF-κB p65 subunit (p65), phospho-nuclear factor NF-κB p65 subunit (p-p65), CXCL2, JAK1, phospho-Janus kinase 1 (p-JAK1) and TYK2 in the cells were detected. The levels of interleukin-1β (IL-1β), interferon-α (IFN-α), interferon-β (IFN-β), and TNF-α in cell supernatants were detected. The results showed that after the RAW264.7 cells were infected with PCV2 for 16 h, the mRNA expression levels of STAT1, STAT2, JAK1, TYK2 and Nfκbia were significantly upregulated (P<0.05), mRNA expression levels of Ccl3, CXCL2, TNF-α, Rel, Nfκbid and Nfκbiz were significantly downregulated ( P<0.05), the protein expression levels of Stat1, p-Stat1, Stat2, p-Stat2, JAK1, p-JAK1 and TYK2 were significantly upregulated ( P<0.05), protein expression levels of IκB, p-IκB, p65 and CXCL2 were significantly downregulated in RAW264.7 cells ( P<0.05), and SSP at 200 mg/L significantly regulated the imbalance in the expression levels of these factors (P<0.05). The study indicates that SSP modulates inflammatory response and immunosuppression induced by PCV2 infection through JAK-STAT/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

N Liangyou 769 was a new combination of green and high-quality late indica two-line hybrid rice bred by Nanping Institute of Agricultural Sciences and Wuyishan Kelixing Seed Industry Co., Ltd., which was approved by Fujian Crop Variety Approval Committee in 2021. This variety was planted as the late rice in Datian County from 2020 to 2021, showing the characteristics of regular population, strong tillering ability, large panicle and more grains, high and stable yield, good rice blast resistance and wide adaptability. [ABSTRACT FROM AUTHOR]

The influence of magnesium ion to phosphorus ratio (denoted as Mg/P) .initial pH and incubating time on MgPs phase transition are investigated. The phase transition processes of the MgPs were monitored by 31P NMR, IR and Raman technology, and the obtained crystal formations of magnesium phosphate were characterized by XRD. The results show when the pH is 9. 0, Mg3 ( P04 ) 2 • 5H20 can be generated in 30 min. When the pH is less than 8.0, MgHP04 • 3H20 is formed at the onset stage. Then Mg3 ( P04 ) 2 • 5H20 phase could be formed from Mg2 (P04) OH • 3H20. With the initial pH at 7. 4, MgHP04 • 3H20 is generated,then transform to Mg3(P04)2 • 5H20 with the Mg/P ratio at 1 in the incubating solution, however, Mg3 ( P04 ) 2 • 5H20 can be formed with Mg/P at 0. 25 and 0. 67. When the Mg/P ratio is set at 4,the MgHP04 • 3H20 phase could be kept for 24 h due to the contribution of the excessive magnesium [ABSTRACT FROM AUTHOR]

The localization methods based on line cloud can protect scene privacy, but they also face the risk of being cracked by a privacy attack algorithm proposed by Kunal Chelani et al. This attack algorithm can recover approximate point clouds from line clouds, but Us computational efficiency is low. To address this issue, a parallel optimization algorithm is proposed and evaluated in terms of running time and speedup ratio. Specifically, the CPU multicore parallelism and the GPGPU parallelism are implemented using the SPMD pattern and the pipeline parallel pattern respectively. Furthermore, the data parallel pattern is adopted to implement heterogeneous computing, to achieve the highest degree of parallelism. Experimental results demonstrate that the maximum speedup ratio of the parallel optimization algorithm is 15. 11, and the minimum is 8. 20. Additionally, compared to the original algorithm, the parallel optimization algorithm ensures the relative error of the recovered point clouds within 0.4% of the original error, ensuring the accuracy of the algorithm. This research holds significant importance and reference value for line cloud privacy attack algorithms, as well as for privacy protection algorithms in Line Cloud under different scenarios and other density estimation problems. [ABSTRACT FROM AUTHOR]

In his book, Counter-behaviors of Chinese Peasants, 1950 – 1980 , historian Gao Wangling defines "counter-behaviors" (fanxingwei) as the everyday actions of shirking and non-compliance by peasants under the disguise of being weak and subservient. This article, as a critique of Gao's work, reexamines the origins, evolution, and eventual formation of the counter-behaviors of Chinese peasants during the state-led collectivization movement in the 1950s, the impact of counter-behaviors on the collective economy and the administrative system, and their relevance to the initiation of rural reforms in the 1980s. It also discusses the implications of the counter-behaviors for understanding the origins of reforms in present-day China and posits that counter-behaviors may function as stimuli for new reform measures in a given context of state-society relations. It further argues that counter-behaviors, for all the possible effect of mitigating the damages to the interests of local people, could also result in the losses of both the state and peasants. As an alternative or correction to counter-behaviors, the author calls for a top-down readjustment of the deficient aspects of state-society relations and a new model of positive interactions between state authorities and local society under rationalized governance institutions. 本文在梳理《中国反行为研究（1950–1980）》一书文脉的基础上，通过分析上世纪五十年代国家集体化运动中农民反行为的起源、发展与定型过程，以及人民剬社时期农民反行为对集体经济与官僚体制的影响，从而揭示农民反行为如何推动八十年代农村改革的议题。本文还延伸讨论了反行为对当代中国改革的启示意义，认为在特定国家—社会关系背景下，反行为也许是促生当前中国改革的主要压力机制。其尽管对民众减少利益损失有一定作用，却代价高昂，甚至造成国家和社会的双输。因此要克服其弊端，还是应该主动改革不合理的国家与社会关系格局，将民众以反行为对制度或政策所做的负向反馈转变为合理制度下国家与民众的正向博弈，并最终重塑民众尤其是底层群体与国家的互动模式。 (This article is in Chinese.) [ABSTRACT FROM AUTHOR]

This paper, which has brought the factors of resource, energy and environment into the efficiency evaluation system, empirically studies the low carbon economic efficiency and its variation trend for the 16 iron & steel listed companies in China from 2007 to 2011 by using the DEA method and Malmquist productivity index. The result shows that the technical efficiency is generally low, which is caused by both the pure technical efficiency and the scale efficiency. The Malmquist productivity is in the trend of decreasing, which is mainly caused by the decline of the technical efficiency. The technical progress index has only weakly negative effect. Through the analysis of the influencing factors of the low carbon economic efficiency in iron & steel listed companies, this paper shows that both energy structure and product structure have conspicuous negative correlation. On the other hand, technical progress, environment protection investment and government regulation have no significant positive correlation. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the highly homologous sequences of theanine synthetase genes and glutamine synthetase genes of tea plant, speculate their evolutionary relationship, predict their structures, natures, functions and differences of enzyme active sites, and then to provide a basis for CsTS genes function studies of tea. Two gene sequences logged on NCBI were cloned, the expression of enzymes activities was verificated through HPLC and LC-MS and phylogenetic analysis was implemented within the searching result. The expression of enzymes in E. coli suggested CsTS and CsGS had different catalytic activities although their high homology. The primary and secondary protein structures of CsTS and CsGS were analyzed and the result showed that there was no significant difference between them, but the third protein structure analysis by homology modeling in the catalytic sites showed three differences in the catalytic sites, which could lead to the difference of enzyme activity. In this research, CsTS gene sequences were firstly identified as the members of GS gene family through phylogenetic analysis. According to cellular localization prediction, CsTS should belong to cytoplasmic GS(GS1), for its kinship close to grape, upland cotton, rubber tree, arabidopsis etc. [ABSTRACT FROM AUTHOR]

To study the problem about dynamic destabilization of the reentry vehicles, the bifurcation theory of nonlinear autonomous dynamic system is used together with the unsteady Navier-Stokes equations simulating the pitching process. The investigations shown th at, the astronautic vehicles reentering into the atmosphere would generally occur a dynamic destabilization of pitching motion as their flight Mach number decreased, and the phenomenon of dynamic destabilization befallens at the point of the Hopf bifurcation, furthermore, there are two types of Hopf bifurcation named subcritical Hopf bifurcation and supercritical Hopf bifurcation. To validate the theory of the Hopf bifurcation, two reentry configurations are numerically studied. One is the Japanese capsule OREX, composed of a spherical cap facing forward and a reversed cone facing backward. With Mach number decreases in the reentry process for the capsule, the pitching motion would evolve from a point attractor to a periodic attractor, and the critical Mach number is about 2. 2 when the subcritical Hopf bifurcation occurs, the theory analysis and simulation result is in good agreement with the experiment and flight test results. The other configuration is a flat-nose winged double-cone body, with the decrease of Mach number, its pitching motion would evolve from a periodic attractor to a point a ttractor, and the critical Mach number at which the supercritical Hopf bifurcation occurs is about 6. 8. [ABSTRACT FROM AUTHOR]

The concept of neoadjuvant chemotherapy was first proposed in 1983. Currently, although there is argument in the role of neoadjuvant chemotherapy in the treatment of cervical cancer, the potential advantage of neoadjuvant chemotherapy is apparent gradually by the development of the operation skills and methods. It can effectively reduce tumor volume, increase the success rate of operation, and it can also delay the delivery until fetal viability has been reached. Neoadjuvant chemotherapy is one of the new therapeutic method for locally advanced cervical cancer, advanced cervical cancer and cervical cancer patients during pregnancy. In this essay, the concept, argument, mechanism and the role of neoadjuvant chemotherapy in the treatment of cervical cancer were reviewed. [ABSTRACT FROM AUTHOR]

An improvement project of displacement sensor experiment system was put forward. A micro-stepper motor was used to control the displacement. The subdivision control strategy was adopted to keep it running smoothly. The stepping motor driving system adopted 3957. AT89C52 SCM was used as centre controller, and AD574 was used as AD converter, LCD 1602 and freestanding button were used as man-machine interface The new system not only could achieve the original purpose, but also could improve experiment efficiency and the credibility of the experimental data. Thus the limited in-class experimental class hours were saved, Experimental capacity was expanded and its quality was improved. [ABSTRACT FROM AUTHOR]

With the development of modern industry, heavy metal water pollution has become one of the most important environmental problems. Heavy metal ions are highly toxic and difficult to degrade, being harmful to humans, aquatic animals, and plants to a large extent and damaging ecosystems. The advantages of low cost, high removal efficiency and recyclability of the adsorption method make it one of the important methods of wastewater treatment. Biomass materials are rich in resources, low cost, green and environmentally friendly, and have been widely studied as new adsorbent raw materials. Based on this, taking metal-organic framework, zeolite and biochar biomass materials as examples, this paper first reviews the preparation and modification methods of biomass matrix composites and summarizes the influence of the properties of adsorbents on metal ion adsorption, secondly elaborates the adsorption mechanism between them and metal ions, and finally puts forward the prospect of biomass matrix composites in the development of water pollution control. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a new segmentation method which integrates polarimetric, statistical distribution and geometric shape features of polarimetric SAR image based on the Fractal Network Evolution Algorithm (FNEA). Firstly, the similarity criterion of polarimetric features between adjacent objects was acquired based on the Pauli decomposition, while the similarity criterion of statistical feature was constructed via the coherency matrix Wishart distribution hypothesis. Secondly, a multi-feature integration strategy in objects merging was established, and polarimetric feature values were stretched in advance to make the heterogeneities of polarimetric, statistic distribution and shape features between adjacent objects to be at the similar level. Then, an integrated multi-feature segmentation flow was built according to the above processes. Lastly, this method was verified with RADA-RSAT-2 image of Altona and L band ESAR image of Oberpfaffenhofen, suggesting that it can effectively reduce the speckle effects and obtain accurate segmentation results, especially in the homogeneous texture areas like farmland and lakes. [ABSTRACT FROM AUTHOR]

By combining the ideas of random concentration in physical simulation and the piecewise approach, the random process of diffusion density of the middle-long distance segment is performed, then a novel subparagraph ink spread function is proposed for simulating the ink diffusion effect. A novel rendering method of Chinese painting style based on piecewise function is proposed. According to the design key points, the overall framework of the proposed method is designed. Firstly, the mean filter is used for smoothing preprocessing of the image. Secondly, the K-means clustering algorithm is adopted for image segmentation so as to simulate the tonal gradation effect expressed by ink shades in Chinese painting. Thirdly, the morphological method is used to detect the edge points. Fourthly, the self-defined piecewise function is applied to the detected edge points to simulate the effect of the diffusion of ink edges, thus obtaining the rendered image of Chinese painting style. Finally, HTML5 is used to implement the proposal. The proposed algorithm can generate a more realistic effect for ink simulation and ink diffusion of Chinese painting style. [ABSTRACT FROM AUTHOR]

For the feature of high hardness, high wear resistance and other characteristics, ceramic materials are suitable for guideway. However, considering the complex processability of ceramic materials, it is necessary to adapt new technology of mechanical lapping and polishing, to reduce tiny cracks and stress concentration, and to improve profile accuracy and fatigue resistance. During the processing period, the ceramic guideway is grinded and lapped to achieve micro-level precision, then polished with robots polishing system. The plane face accuracy is detected by the interferometer at the same time. Based on the detected data and polishing process, the ceramic guideway is further processed to achieve higher accuracy. In the process of experiment, the PV value of ceramic guideway face is reduced from 2. 348 mm to1. 844 mm, and the RMS value of ceramic guideway face is reduced from 0. 625 mm to 0. 394 mm. In order to improve the accuracy of ceramic guideway, it is a new way to combine optics detection method with specific polishing technology. The experiment results show that this method is effective. [ABSTRACT FROM AUTHOR]

Due to the fact that the color of sugarcane nodes and internodes are similar to each other, and the interference of white fruit powder on the skin, node recognition and location were affected seriously. A method for node identification and localization was proposed based on hyperspectral imaging. 236 sugarcane samples (874 ~ 1734 nm) were collected by the hyperspectral imaging acquisition system. Using successive projections algorithm (SPA) to extract characteristics band (1022 nm, 1062 nm, 1456 nm, 1609 nm and 1649 nm), the PLS discriminant model were established by these 5 characteristic bands. The 20 groups of sugarcane hyperspectral images were identified by the established model, the binary image of sugarcane was gotten, image processing was used to locate the position of node. The experimental result showed the standard deviation was 0.7 mm, the maximum absolute error was 2.6 mm, and it could identify and locate the sugarcane node effectively, provide technical support for automatic cutting of sugarcane which could prevent injury buds. [ABSTRACT FROM AUTHOR]

Points cloud of street trees were obtained by vehicle LiDAR. The existing hierarchical projection algorithm was combined with heuristic knowledge of object characteristics to achieve the points cloud extraction of each tree. Fitting circle by least squares, the diameter at breast height (DBH) and row spacing of street trees were measured by Matlab programming. The experimental results showed that the root mean square (RMS) error of DBH and row spacing of LiDAR-based measurement and manual measurement were 0.008 7 m and 0.010 3 m, the correlation coefficients were 0.968 2 and 0.999 6. The proposed method had high precision and wide measuring range and provided quality data for the detection of distribution and growth state of street trees. [ABSTRACT FROM AUTHOR]

The imported cryogenic horizontal centrifugal pump is widely used for LNG loading pump in domestic small and medium natural gas liquefaction plant. The pumps have some disadvantages, such as expensive price, easy leaking, large LNG loss, and complex installation and removal. The immersed pump was considered to be used for LNG loading pump, and the technical research and equipment development have been completed. Relying on actual LNG plant, the equipment performance testing was also finished to realize the localization and engineering of LNG loading pump. [ABSTRACT FROM AUTHOR]

In order to meet the requirements of the credit teaching management system, engineering training course was reformed from centralized to decentralized operation. We improved the teaching operating mechanism, operation management system, student achievement assessment, teacher assessment and training, school enterprise cooperation mechanisms of engineering training course. Application in practice teaching was effective. Engineering College was evaluated as beijing experimental education demonstrative center and Beijing excellent education teams. [ABSTRACT FROM AUTHOR]

In recent years, the crops have severely suffered from frost damage with the deterioration of the global climate. Conventional methods of frost protection, such as smoking, covering, and irrigation may be effective in many cases, but they are time-consuming, and some methods even easily caused environmental contamination. So study of scientific and high-effective artificial frost prevention equipment has become very necessary and an urgent need. Most wind machines for frost protection are still in the pilot stage at home and abroad, and their height and blade length, etc, are not for taller plants, such as apple trees,peach trees, and cherry trees. The Gansu meteorology department, using the principle of disturbing the air of mechanical power, invented the first domestic elevated wind machine for frost protection with a long blade, which proved the feasibility of frost protection by air in disturbing surface layer. The machine construction has the main components as follows: blade,pipe tower, fan base,underground base,engine and ladder. In order to study the effect of frost prevention and the extent of protection for an elevated wind machine, the instrumentation layout was as follows: at a distance of 53 m from the wind machine, installing a 10 m gradient observation tower of temperature within protected areas, and at a distance of 190 m from the wind machine, also installing a 10 m gradient observation tower of temperature outside protected areas as the effect of frost prevention control. Two gradient tower of temperature at 1.0, 2.0, 3.0, 4.0, 5.0, 8.0 and 10 m from the ground installed a temperature sensor respectively, which observed vertical temperature distribution; also at 2 m from the ground install a humidity sensor observed relative humidity. A projector to the ground of the wind wheel rotation axis of the wind machine for the center line, arranged the horizontal distribution of an observation point at intervals of 10 m, a total of 10 observation points, and each observation point 1, 2 and 3 m from the ground were erecting a portable anemometer for wind observation. In this paper, based on the contrast test observation data of the processes of a strong decrease in temperature from October 19 to 21,2013, the frost protection effect of the first self-designed domestic elevated wind machine for frost protection with a long blade was evaluated. The main analysis results were as follows: 1) Under the temperature inversion condition, the upper and lower air disturbance caused by one elevated wind machine with a 6m diameter blade of 12 kW power and 8.5 m in height made the temperature inversion disappear and the temperature within 1-3 m greatly increased. Relative humidity decreased rapidly, effectively preventing the generation of frost in the protected area. 2) The disturbances-affected area of strong wind was about 20 m, and wind speeds at 3, 2 and 1m from the ground were 4.0, 2.1 and 1.6 m/s respectively. The effective protection range of one wind machine was 20 m to 100 m, within level range of 20-100 m, wind speed changes of 1-3 m showed a reduced trend with fluctuations. The effective protection area of one wind machine was 1.73-3.07 hm2. The result of the research provides a reference for scientific and high-effective artificial frost prevention and promotion of an elevated wind machine for frost protection with a long blade use. [ABSTRACT FROM AUTHOR]

Among all the security risks, the sharing of resources and data communication in virtual machines are most concerned. This paper proposed an access control security model which combined the Chinese Wall and BLP model. It introduced BLP with corresponding adoption with PCW security model. This model could be used to control the resources usage and event behaviors in virtual machines. The experimental results show its effectiveness and safety. [ABSTRACT FROM AUTHOR]

The thrust vectoring control technology is the main technology for the 4th generation fighter. The computational study of interaction flows between vectoring jet and high speed main flow around a simplified fighter configuration is presented. The infections of the parameters such as Mach number of main flow, attack angle, nozzle deflection angle, Mach number, total pressure and total temperature of jet flow are system researched. The physical mechanism of the main flow/vectoring jet flow interaction is also analyzed. Numerical simulation results show that for the simplified fighter configuration, the thrust vectoring jet effect on the high speed main flow is only effects on the aircraft components near the nozzle exit and have little effect on the aerodynamic characteristics of aircraft except at high angles of attack. However, the high speed main flow has strong interaction with thrust vectoring jet flow. With the increasing of the angle of attack and Mach number the decrease of thrust vectoring angle are increasing. [ABSTRACT FROM AUTHOR]