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Human health and environmental concerns caused by the massive volatile organic compound (VOC) emission have attracted widespread attention recently. VOCs are toxic and difficult to eliminate; moreover, they come from a wide variety of sources. Efficient and environmentally friendly removal of VOCs has always been one of the primary concerns in the catalytic chemical industry. Presently, the commonly used methods for VOC removal include absorption−adsorption, biodegradation, thermal catalysis, and membrane separation. However, these methods have several drawbacks, such as high initial investment, expensive materials, high energy consumption, low catalyst efficiency, and incomplete treatment. Photocatalytic oxidation (PCO) technology is considered to be one of the effective methods of environmental pollution control. PCO can directly use solar energy to remove various environmental pollutants. Thus, PCO has inherent advantages such as low consumption, environmental protection, no secondary pollution, and convenience. Photocatalyst is a core step in the PCO process, and as aphotocatalyst studied for the longest time, titanium dioxide (TiO2) has the advantages of high cost-effectiveness, good stability, strong photocatalytic degradation capability, and producing no harmful byproducts. However, bottleneck problems such as the inability to utilize visible light and low separation efficiency of photoexcited charge carriers have always restricted its advancement. Thus, the inherent limitations of TiO2 need to be overcome, and its capability to degrade VOCs via PCO needs to be improved. These modifications can improve the PCO performance through the following mechanisms: (1) By introducing electron trapping levels in the bandgap, which will create some defects in the TiO2 lattice and help trap charge carriers, and (2) by slowing down the electron carrier loading rate to increase VOC degradation. Thus, considering the basic principle of TiO2 photocatalytic removal of VOCs, this study focuses on the key factors affecting the photocatalytic reaction. Beginning with aspects such as metal/nonmetal doping, semiconductor recombination, defect engineering, crystal plane engineering, carrier adsorption, and morphology control, the research on the design of TiO2-based materials and their application in the field of photocatalytic degradation of VOCs in recent years are systematically summarized; moreover, a brief introduction of its control parameters and applications in practical engineering and prospects on how to further improve the use of TiO2-based materials for the PCO technology of VOCs is provided. This review will provide parameter support and optimization suggestions for the research on the degradation of VOCs by TiO2-based photocatalytic materials to help researchers lay the foundation for future research.

Job scheduling of high-performance clusters is usually implemented by the job scheduling system. Filling in the job running time accurately can greatly improve the efficiency of job scheduling. Existing research usually uses machine learning for prediction, and the prediction accuracy and practicality can be further improved. In order to further improve the accuracy of cluster job running time prediction, cluster job logs are firstly clustered, and job category information is added to job features. Secondly, the job log data is modeled and predicted using the attention-based NR-Transformer network. In data processing, according to the correlation with the prediction target, the integrity of the feature and the validity of the data, 7-dimensional features are selected from the historical log dataset, the dataset is divided into multiple job sets according to the length of the job running time, and then each job set is trained and predicted separately. The experimental results show that, compared with traditional machine learning and BP neural network, its timing neural network structure has better prediction performance, and NR-Transformer has better performance on each job set. [ABSTRACT FROM AUTHOR]

Arsenic pollution has become a serious problem in the world. Arsenic in soil, air and water is threatening crop production and human health. Remediating arsenic contaminated soil has become a research hotspot at home and abroad. Arsenic pollution also exists m copper smelting process. In this paper, a soil with serious arsenic pollution around a smelter in Jiangxi Province was taken as the research object. Through laboratory research, the effects of the concentration, liquid-soil ratio and extraction time of citric acid, EDTA and saponin on arsenic extraction were explored, and the causes were analyzed. The results showed that the arsenic extraction rate of citric acid, EDTA and saponin was related to their concentration, liquid-soil ratio and extraction time, and the comprehensive removal capacity was 50 g/L citric acid, 40 g/L saponin and 30 g/L EDTA, respectively, which reached the highest extraction rate 68.54%, 61.94%, 55.70% when the liquid-soil ratio was 20 mL/g and extraction time was 24 h. This study can provide technical reference for arsenic contaminated soil remediation. [ABSTRACT FROM AUTHOR]

The change and utilization of water resources in Taihu area in Ming and Qing dynasties caused extensive concern of the officials and the public. The various types of collapse caused by environmental changes and human activities affected the basic interests of the local government. In the use of water resources, the rulers of the dynasty proposed a great number of measures and strategies to deal with the system. The interests of all parties had reached a balance between the states temporarily, however, due to the persistent effects of the environment and society, the balance was often broken. The competition of interests and tension among the people in the south of the Yangtze River, local despots and state officials had been clearly presented. In particular, the problem of water and soil subsidence became serious which was regarded as "ash heap" by the local government officials, and it also affected the regional water conservancy. In Ming and Qing dynasties, it was normal that people competed with water for the fields and government competed with the public for profit, and it was also the due performance under the environmental changes and survival pressure, which is of universal significance. [ABSTRACT FROM AUTHOR]

Jiangnan in Ming and Qing Dynasties is a fundamental economic zone, wealth and taxes powerhouse, and its county administrative is very troublesome. At the same time because of the imperial prosperity, gentry intensive, industrial and commercial landlords are powerful, Jiangnan is the place where local interests and national interests are very prone to conflicts. County is the basis of the ruling dynasty, the effective display of county administration is a prerequisite for local development. The heavy liturgical, corrupt official, social conflicts, dynastic order crisis and so on in Jiangnan, all these problems need to cleanup start from the grassroots country administrations. The nervous relations between officials and the public, officials give the public tremendous liturgical pressure and barely able to maintain the balance between them, are the real problems faced with the county officials, "county community", which should exist in Jiangnan was popular influenced by courtiers and the rich, county officials need to carefully grasp the local gentries' trends, avoiding its threats and hazards to official police, and take full advantages of their impact for promoting the official full control of urban and rural society, try to guide the local society tend to healthy development. [ABSTRACT FROM AUTHOR]

Internet has become an undivided part in modern life, therefore an effective and stable protocol becomes more and more important. The paper studies the interoperability testing of IS-IS protocol, which is a major interior gateway protocol. Firstly, a hierarchical CPN model of the interoperability testing of IS-IS protocol is established. Secondly, the full state space is automatically generated by the CPN tools, and test sequences and test cases are generated according to the test purpose. Finally, a test platform is built in Windows XP and a routing simulation software, named GNS 3, is used to imitate Cisco 7200, Cisco 3640, etc. . The obtained test cases are used to do the IS-IS interoperability testing, and the test reports are given after the test results are analyzed. [ABSTRACT FROM AUTHOR]

Taking stay-green sorghum (B35) and non-stay green sorghum (Sanchisan) as test materials, a pot experiment was conducted to study their leaf osmotic adjustment and chloroplast ultrastructure at flowering and filling stages under impacts of drought stress (45% -50% of maximum field capacity). For the two sorghum lines, drought stress caused the reduction of their leaf free water content and relative water content, and increased the leaf bound water content, water saturation deficit, and electrical conductivity, with the increment or dement being larger for Sanchisan than for B35. Drought stress increased the leaf soluble sugar content and proline content, with the increment of the soluble sugar content being larger for Sanchisan and the increment of the proline content being larger for B35, while decreased the leaf soluble protein content, with the decrement being larger for Sanchisan than for B35. The chloroplast ultrastructure of both B35 and Sanchisan under drought stress was damaged to some extent, but the damaged degree was obviously lower for B35 than for Sanchisan. The findings indicated that stay-green sorghum had a greater adaptation to drought stress through stronger osmotic adjustment. Key words: stay-green; drought stress [ABSTRACT FROM AUTHOR]

Based on the condensation growth theory of polydispersed aerosols, particle size distribution during the heterogeneous condensation process was investigated in this study. Also, the influences of operational conditions (residence time, degree of saturation and temperature) and PM2 5 properties (size and dispersity) on particle growth were tested. The results show that particle size range narrows rapidly as the residence time of particles increase in the supersaturated vapor environment. Consequently, the initial polydispersed fine particles shift to monodispersed micron-sized droplets by vapor heterogeneous condensation. Under a higher supersaturation condition, the driving force for vapor condensation is greater and thus, the particles grow more rapidly. In cases with the same level of supersaturation, higher gas temperatures can promote the condensation droplet to grow bigger. It has also been found that the condensation growth effect is not dependant on the initial particle size distribution parameter, such as particle diameter and dispersity because the particle sizes trend to the same value after vapor heterogeneous condensation. [ABSTRACT FROM AUTHOR]

In the Ming and Qing period, the local economic development in Jiangnan district is closely related to the change of society and culture. Influenced by geographical factors, people's lifestyle and culture practice vary from one district to another. In the Jia Ding area, the local people treat the cotton industry as their main industrial economy. However, when it comes to the national features of products, bamboo carving comes first. Since the middle of the Ming Dynasty, Jia Ding has become the most important carving center across the nation, with bamboo carving masters coming forth in large numbers. Under the influence of the support from the government and the pursuit of the literary men, the Ji Ding bamboo carving industry has comes to its peak. Since the emperor Qianlong period, the delicacy in bamboo carving has been recessed. Bamboo carving is becoming mainly used by ordinary people in daily life and the commercialization is becoming more and more obvious. Although it is large in sales, the delicate ones are becoming less. [ABSTRACT FROM AUTHOR]

Under the conditions of simulated micro-habitat in laboratory, and by using experimental ecological methods, this paper evaluated the suitability index (HSI) of young Procypris rabaudi for habitat factors (substrate, light intensity and water depth). The habitat suitability models of the young P. rabaudi were established, and the minimum habitat area of the young P. rabaudi was estimated. The young P. rabaudi preferred the habitats with the gravel diameter from 10 to 15 cm, light intensity from 0. 2 to 1. 8 lx, and water depth from 0 to 15 cm (distance from the bottom of the tank). The three suitability index models of the substrate, light intensity and water depth for the young P. rabaudi were SIS =1. 7338e-0. 997x (SIS is the suitability index of substrate, and x is the gravel diameter; R2 =0. 89, P<0. 01), SIL =3. 0121e-1. 339x (SIL is the suitability index of light intensity, and x is the light intensity; R2 =0. 93, P<0. 01), and SIW =2. 4055e-1. 245x (SIW is the suitability index of water depth, and x is the water depth; R2 =0. 97, P<0. 01), respectively. Arithmetic mean model HSI =(SIS +SIL +SIW) /3 was most available for the estimation of the habitat suitability of young P. rabaudi. A total of seven groups of young P. rabaudi which established and maintained a relatively stable habitat area range were found. This habitat area ranged from 628 to 2015 cm2, with an average of 1114 cm2. [ABSTRACT FROM AUTHOR]

Agricultural landscape refers to various forms of agricultural land formed due to historical or cultural factors, with the rural settlement and its surrounding natural environment as the background and agricultural activities (farming, animal husbandry, etc. ) as its base. The typical agricultural landscape includes "Mulberry-Dike-Fish-Ponds", "terrace farming", "fish-raising in rice fields", etc.. Agricultural landscape has its own features, which represent the unique artificial ecosystem established over thousands of years of farming activities. They are also land forms based on the geography, climate, soil, hydrology and other environmental factors in rural areas, in combination with unique features of local history, society, economy, and culture. In the process of developing rural tourism, a lack of comprehensive and deep understanding of agricultural landscape features embedded with farming history and culture, or blind adoption of methods in urban landscape construction will lead to the loss of the core value of agricultural landscape and rural characteristics. In order to maintain the features of agricultural landscape resources in rural areas in developing rural tourism, scientific explorations in agricultural landscape resources have become essential to research. According to this essay, in order to protect agricultural landscape features, a deep understanding of the systematic functions of agricultural production, people's life and the ecology is first and foremost; this could then be followed by the principles of integrity, sustainable development of resources, regional differentiation and coordinated coexistence. Under the guidance of these principles, it is imperative to monitor and evaluate the forms of agricultural landscape and ecological system by in-depth field investigation and with computer-aided GIS, RS and other modern technologies. The planning schemes of development of rural tourism landscape are proposed on the basis of these investigations and need to gain multidisciplinary scientific evidences. The subsequent construction and management should proceed in accordance with the protection of agricultural natural landscape and maintenance of local culture. In the process of tourism development, real-time control and management in the quantity and quality of the regional agriculture landscape and utilization of the ecological environment should be implemented, so should the structure of ecological system in agricultural landscape maintained in order to realize effective protection and sustainable use of agricultural landscape. With tourism development and organic regeneration in the traditional agriculture landscape of "Mulberry-Dike-Fish-Ponds" located in Seven-stars village, Xiqiao town, Nanhai city, Guangdong province as a case for study, this paper discusses how to realize effective protection and sustainable utilization of agricultural landscape features in tourism development. The "organic regeneration" of "Mulberry-Dike-Fish-Ponds" of agricultural landscape is to respect its inner structure and mechanism of ecological system, to make further improvement according to the conditions of the new era and need of meeting new function requirements, to carry out ascension transformation, to restore its biological cycles of the ecological system mechanism structure and the Field-edge fish ponds modification for tree planting, and at the same time to recover its biological cycles and structure relationship between Field-edge and fish ponds with consideration of leisure travel and promoting wetland landscapes. Therefore, the deserted Mulberry-Dike-Fish-ponds system will not be simply constructed to be lakes, ponds or paved plaza for tourism development. By exploring, protecting and maintaining the features of agricultural landscape, the Seven-star Village has turned "Mulberry-Dike-Fish-Ponds" into a tourism region with its characteristics in agricultural production, people's life and the ecology, as well as an agriculture base known for its pollution-free fruits, vegetables and fish. [ABSTRACT FROM AUTHOR]

Taking one-year-old dormant shoots of Pistacia chinensis and Koelreuteria integrifoliola as test materials and the shoots of northern indigenous tree species K. paniculata as the control, the changes of their membrane-lipid peroxidation, antioxidative enzyme activity, and organic osmoregu-latory substance content under artificial cooling were studied, aimed to analyze the differences of the three tree species in cold resistance. With the decrease of temperature, the ion leakage percentage of the three tree species increased in S-shape, and the SOD and POD activities decreased after an initial increase. The MDA, soluble protein, and soluble sugar contents of K. integrifoliola and K. paniculata under decreasing temperature decreased after an initial increase, while those of P. chinensis had an increasing trend. The semi-lethal temperature ( LT50) of K. paniculata, K. inte-grifoliola , and P. chinensis calculated by the Logistic equation of ion leakage percentage was -27. 2 °C , -23. 7 °C , and -27. 0 °C , respectively. Among the three tree species, K. paniculata had the strongest cold resistance, followed by P. chinensis, and K. integrifoliola. [ABSTRACT FROM AUTHOR]

Based on the conventional lumped parameter equivalent circuit model, the electrical characteristics of piezoelectric transformers (PTs) in series-parallel connection were analyzed using Y-parameter matrix. The voltage gain, output power and efficiency as function of parameters and the number of connected piezoelectric transformers were derived and simulated. And the electrical characteristics were simulated by using radial-mode vibrating PTs. Two piezoelectric transformers at the voltage gain of 0.081 6 with input and output parts isolated were tested. After series-parallel connection the voltage gain was reduced to 0.0406 on the same load of 20 ∩. The computed and experimental results verify the fact that the series-parallel connection of piezoelectric transformers can enhance the voltage step-down ratio. Series-parallel connected piezoelectric transformers can realize voltage step-down. [ABSTRACT FROM AUTHOR]

The clayey farmland soil in black soil region of Northeast China, due to the existence of thicker plough pan created by unreasonable tillage, is a main limiting factor for local agricultural production. In this paper, a field experiment was conducted to study the construction effect of fertile cultivated layer on crop yield, soil physical properties, soil moisture content, and soil microbial number. After the construction of fertile cultivated layer, the soil had a thicker cultivated layer, and the crop yield was increased. Comparing with traditional tillage, applying straw and organic manure into 20-35 cm soil layer decreased soil bulk density by 9.88% and 6.20%, increased soil porosity by 9.58% and 6.02%, and enhanced soil saturated hydraulic conductivity by 167.99 and 73.78%, respectively, indicating that the construction of fertile cultivated layer could improve soil aeration and water permeability, and enhance the infiltration of rainfall. The soil moisture content and water use efficiency under the application of straw and organic manure into plough pan were higher than those under traditional tillage, and a positive correlation was observed between the moisture content in 0-35 cm soil layer and the emergence of maize seedlings. Due to the increased organic carbon source and aeration in the constructed fertile cultivated layer, soil microbial number was also increased. [ABSTRACT FROM AUTHOR]

With the advent of an economic globalization and knowledge economy, especially after China's entry into WTO, private scientific and technical enterprises are required to upgrade their concept of globalization and carry on an internationalization strategy. According to the existing status of private scientific and technical enterprises, we can divide them into three growing patterns: intergrowth, gregarious and solitary. The intergrowth pattern in internationalization is defined as a new cooperation arrangement between middle and/or small enterprises and multinationals. It is characterized by an interdependence on each other. Multinationals gain increasing elasticity and efficiency by integrating with small enterprises, and at the same time provide chink opportunities for small ones. Small enterprises specialize themselves and form scale of economy by providing higher demand for multinationals. The gregarious pattern is a clustering behavior among enterprises with same sorts, embodying coexistence and assistance among them. This pattern is the main way of internationalization for private scientific and technical enterprises at present. The last pattern is solitary in that internationalization is based on the independent growth of the enterprises themselves. This pattern fits for enterprises of higher level internationalization. There are not many enterprises in china that can take on such a pattern. As a matter of fact, these three patterns play a very important part in the competition between private technical enterprises and multinationals. [ABSTRACT FROM AUTHOR]

To improve the use efficiency of large-scale instruments and equipment, we have made many attempts, for example, to set up a technical advisory group with professors; to establish group management, and to call for "multiskill"; to implement strict reservation system of the machine; to set up the night shift system, to extend the service hours; entry tutorial system; to open seminars; to participate in the national metrology authentication actively. These measures improved the level of the laboratory in an aü-round way etc, and made Analysis & Testing Center become a unique public platform. [ABSTRACT FROM AUTHOR]

[Purpose/Significance] Accelerating the construction of digital rural areas is a strategic direction for comprehensively promoting rural revitalization, which plays an important role in promoting the modern basic living conditions in rural areas, improving the quality and efficiency of farmers' production and living, and achieving the development of urban-rural integration. In recent years, the construction of digital rural areas has been actively promoted in various regions, and a number of typical models are being explored and practised which has brought more digital dividends to rural residents. However, the regular characteristics of various practices have not been summarized in related research, resulting in poor promotion of best experience models and a lack of directional indicators for digital rural construction in different regions. This paper has summarized the regular characteristics and application mechanisms of diversified digital rural construction practices in China. The relevant conclusions would provide theoretical reference for promoting the construction of digital rural areas in different regions through classification. [Method/Process] Based on the perspective of structural elements and dynamic effects, this paper investigated four typical county-level digital rural construction models as research objects, namely Deqing County, Pukou District, Cao County, and Dianjiang County, in the national or provincial-level digital rural pilot county. Then, it used a multi-case analysis method to explore the regulatory characteristics of different types of digital rural construction models. [Results/Conclusions] The construction of digital rural areas in China mainly involves the integration of urban and rural areas, the integration of industry and city, the integration of point, line, and area, and the promotion of construction throughout the county. Influenced by factors such as the main functions of the construction, the requirements of the construction content, and the resource endowment, location, and transportation of the construction area, the internal and external thrust mechanisms of different construction models also exhibit different characteristics. In promoting the construction of digital rural areas in the future, different regions should fully consider the strength of the main functions of the construction, choose different construction mechanisms and content, so that digital rural areas can benefit more farmers, and help promote the comprehensive revitalization of rural areas. However, there are some shortcomings in this paper, such as the lack of in-depth analysis on the role and functional positioning of farmers, different levels of government, and market subject as participants. More wisdom is needed to embed the operation and maintenance mechanism for the later stage of digital rural area construction in future research.

[Purpose/Significance] "People-centered" is the basic principle of the construction of rural public cultural service system in the new period and the important criterion of efficiency evaluation. During the "14th Five-Year Plan" period, with the continuous improvement of the rural public cultural service system framework and the continuous increase of the total supply, the relevant policies of rural public cultural services have begun to move toward the era of "high-quality", "high level" and "high quality" efficiency improvement. [Method/Process] Based on the policy and demand orientation, this paper constructed the evaluation index system of rural public cultural service effectiveness, and designed 17 specific indicators from 5 dimensions, such as awareness, participation, satisfaction, sense of cultural acquisition, and cultural happiness, and takes the Beijing ecological conservation area as a typical example to carry out the "people-centered" efficiency evaluation of rural public cultural service. [Results/Conclusions] At present, the average score of rural public cultural service efficiency in Beijing's ecological conservation area is 75.90 points, which is in the "medium" level, indicating that the overall efficiency level of rural public cultural service in Beijing's ecological conservation area still has a large room for improvement. The participation score is the lowest, and there is a large difference in the participation level and the sense of cultural acquisition level among groups, indicating that the efficiency level of rural public cultural services has a large room for improvement, and the construction is unbalanced. The ultimate goal of improving the efficiency of rural public cultural services guided by "people-oriented" is to build a rural public cultural service system with everyone's participation and shared by all, meet the new expectations of rural residents for a better spiritual and cultural life, and make public cultural services play a greater role in promoting the comprehensive revitalization of rural areas. In the future, it is necessary to optimize the structure and layout of public cultural service facilities, promote the transformation of public cultural service products from universal to precise, build a multi-level and multi-channel public cultural supply mechanism, and deeply explore and innovate the excellent traditional local culture, so as to improve the efficiency level of rural public cultural services.

Building a safe and controllable, unimpeded circulation, high-quality and efficient smart supply chain system for agricultural products has become an important step to stabilize the agricultural industrial chain and supply chain under the new development pattern.This paper starts with the urgent need of smart transformation of agricultural products supply chain system in the new development situation, analyzes the connotation and framework of high-quality development of smart supply chain system of agricultural products, and analyzes the effect of current construction of smart supply chain system of agricultural products in our country and the main weaknesses.The unbalanced digitization level of each link of the supply chain, the obvious phenomenon of information data island, and the prominent weakness of supporting system construction have become the core issues for the high-quality development of the smart supply chain system of agricultural products. It puts forward the strategic goal of high-quality development of smart supply chain for agricultural products from the 14th Five-Year Plan period to 2035. The key measures to promote the high-quality development of smart supply chain of agricultural products include in-depth research on key core technologies of smart supply chain of agricultural products, construction of big data platform for comprehensive management and service of provincial agricultural supply chain, promotion of digital transformation of all links of agricultural supply chain to deep development, and improvement of traceability system construction of agricultural product quality.

Objective: This study aimed to solve the problem of the low utilization rate of mackerel and the single taste of fish chips. Methods: The specific volume, crispness, hardness, color, fat and acrylamide content of mackerel-yam fish chips made by frozen mackerel, starch and yam powder were determined to study the effects of different aging time, frying time, frying temperature and amount of yam powder on the quality of fish-chips. Results: With the extension of the aging time, the specific volume of the fish-chips gradually increased, when the aging time was 48 h, the specific volume reached 4.14 mL/g, and the hardness also gradually decreased. When the aging time was 48 h and 60 h, the hardness was 382.8 N and 371.5 N respectively. The brittleness first increased and then decreased with the increase of aging time, after 36 h, the brittleness of the fish stick had no significant difference. The best frying time of fish-chips was 40 s, at this time, its specific volume was 4.2 mL/g, its brittleness was 0.354 mm, and its hardness was 357.17 N; when the temperature reached 180 ℃, the specific volume and brittleness of the fish-chips did not change significantly. With the increasing amount of yam powder, the specific volume, hardness, and acrylamide of fish-chips gradually decreased and its brittleness gradually increased, whereas the fat content had no obvious regularity. Conclusion: The fish chips could meet the needs of the public and had potential development values.

The seed industry is the chip of agriculture and seed industry modernization is a significant symbol for agricultural modernization. Internet Plus Modern Seed Industry is an important application scenario of modern agriculture and a concentrated embodiment of scientific and technological innovation in the seed industry. Based on the concept definition and main characteristics of Internet Plus Modern Seed Industry and using field investigation and expert consultation, this study analyzes the characteristics, supporting technologies, and typical applications of application scenarios for different subjects such as government departments, scientific research institutions, and breeding bases. The challenges and demand for the infrastructure, data sharing, key technologies, and commercialization system of the Internet Plus Modern Seed Industry in China are analyzed. Additionally, we propose the development strategy, technical roadmap, and major demonstration projects, to provide a scientific reference for the development of modern seed industry. Specifically, major demonstration projects are urgently required for big data platforms for germplasm resources, new infrastructure for Internet Plus Modern Seed Industry bases, Internet Plus Modern Seed Industry data sharing platforms, and big data intelligent services for the seed industry. Moreover, the intelligent equipment research, development, and manufacturing industry as well as the commercialized breeding software industry should be encouraged to comprehensively promote the intelligent development of modern seed industry.

The modernization of public service governance in rural areas is a crucial component for rural governance in China; it promotes the quality of public services and provides a foundation for improving people’s livelihood and realizing rural revitalization. Based on an investigation regarding rural public service governance in 22 provinces (cities and autonomous regions) in China, we summarize the historical evolution and institutional changes of the public service governance in rural areas, analyze the major challenges faced during the modernization of rural public service governance in China, and propose the strategic objectives, development roadmap, and key tasks for 2050. Multiple problems remain in terms of public education, health care, social security, employment training, and public cultural and sports services. Therefore, the key tasks in the future include: (1) building a coordinated infrastructure system between urban and rural areas, (2) modernizing the governance of rural education, (3) improving rural cultural and sports infrastructure, (4) optimizing the public health service system, and (5) improving the social security system in rural areas. To further modernize rural public service governance in China, we suggest that the key governance objects and the supply list of rural public services should be clarified, the intelligent and digital transformation of governance should be accelerated, and collaborative governance by multiple subjects should be encouraged.

Smart agriculture is an important component of high-quality agricultural development and the overall rural revitalization in China. Research on smart agriculture strategy is significant for developing a medium- and long-term scientific and technological layout and clarifying the development ideas and direction of smart agriculture in China. Against the background of rural revitalization, this study summarizes the macro demand of high-quality agricultural development for smart agricultural science and technologies; it also analyzes the strategic conception, strategic tasks, and development route of China’s smart agriculture development toward 2035. Conclusions show that developing smart agriculture helps address the low quality and efficiency and weak competitiveness of China’s agriculture sector. Furthermore, to achieve the replacements of human power with machines and human brains with computers, and promote the independent technological competitiveness of China’s agricultural sector, an industrial technology system for the smart agriculture that integrates biotechnology, information technology, and intelligent equipment should be established; and smart agriculture should be promoted in a staged manner considering different business entities and industrial needs. Specifically, China should strengthen the top-level design, promote technological research, establish a differentiated subsidy mechanism, integrate industry and village, and encourage applied talent training.

A novel deep Web data discovery strategy was proposed for new generated data record in resources.In the ap-proach,a new graph model of deep Web data attribute value lists was used to indicate the deep Web data source,an new data crawling task was transformed into a graph traversal process.This model was only related to the data,compared with the ex-isting query-related graph model had better adaptability and certainty,applicable to contain only a simple query interface of deep Web data sources.Based on this model,which could discovery incremental nodes and predict new data mutual infor-mation was used to compute the dependencies between nodes.When the query selects,as much as possible to reduce the negative impact brought by the query-dependent.This strategy improves the data crawling efficiency.Experimental results show that this strategy could maximize the synchronization between local and remote data under the same restriction.

This article is focused on the effect of temperature on the corrosion electrochemical behavior of 13Cr martensitic stainless steel under a high temperature and high CO2 partial pressure environment. Cyclic polarization(CP) measurements,electrochemical impedance spectroscopy(EIS),Mott-Schottky plot measurements,ZSIMPWIN software,and scanning electron microscopy(SEM) are used in this study. The results show that the stability of passive films formed on the 13Cr stainless steel surface decreases with increasing temperature under a high temperature and high CO2 partial pressure environment. This leads to increases in the corrosion rate and pitting susceptibility.

Concerning on the acquisition problems on deep Web data integration such as high cost and low efficiency of query selecting,a novel deep Web data acquiring method was proposed based on circular strategy and dynamic knowledge.According to the relationship between deep Web data sources from the same domain,the circulation strategic acquisition of data source in batches was applied in such method,as well as a designed method of query selecting on dynamic knowledge based on integrated systematic.Compared with current,the method reduces the acquisition cost and with more accuracy.Experimental results show that the method can raise the acquisition efficiency of deep Web data integration.

A fiber Raman amplifier with bandwidth of 90 nm using eight pump lasers was presented. Based on the theoretic model, a gain of （11.5±1） dB was obtained with the 25 km SMF manufactured by Corning Corp as gain media. The experimentally measured spectra of signal gain coefficient and inter-pump gain coefficient for different pump parameters are in good agreement with the results of improved theoretic model.

Based on the construction of Changchengling double-arch tunnel with heavily jointed soft rock mass, a model test was carried out to analyze the stress characteristics during the excavation. With the help of monitoring instruments, the datas of stress, strain and pressure were collected and analyzed. Then a numberical simulation was carried out with FLAC3D, and its results verify the conclusions of model test. Combining with numerical analysis, the results of the model test reveals the variation laws of the tunnel surrounding rock stress and the change trends of pressure above and below the middle wall. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of Polyetheretherketone (PEEK) rod semi-rigid pedicle screw fixation system in lumbar spine non-fusion surgery., Methods: A total of 74 patients with tow-level lumbar degenerative diseases who underwent surgery from March 2017 to December 2019 were divided into PEEK rod group and titanium rod group. In the PEEK rod group, there were 34 patients, including 13 males and 21 females, aged from 51 to 79 years old with an average of (62.4±6.8) years old;There were 1 patient of L 1 -L 3 segments, 7 patients of L 2 -L 4 segments, 20 patients of L 3 -L 5 segments and 6 patients of L 4 -S 1 segments. In the titanium rod group, there were 40 patients, including 17 males and 23 females, aged from 52 to 81 years old with an average of (65.2±7.3) years old;There were 3 patient of L 1 -L 3 segments, 11 patients of L 2 -L 4 segments, 19 patients of L 3 -L 5 segments and 7 patients of L 4 -S 1 segments. The general conditions of operation, such as operation time, intraoperative blood loss, postoperative drainage was recorded. The visual analogue scale (VAS) for low back pain and Oswestry disability index (ODI) were compared in preoperatively and postoperatively(3 months, 12 months and last follow-up) between two groups. The change of range of motion (ROM) was observed by flexion and extension x-ray of lumbar., Results: All patients successfully completed the operation. The follow-up time ranged from 22 to 34 months with an average of(26.8±5.6) months. The operative time (142.2±44.7) min and intraoperative blood loss(166.5±67.4)ml in PEEK group were lower than those in titanium group [(160.7±57.3) min、(212.8±85.4) ml]( P <0.05). There was no significant differences in postoperative drainage between the two groups ( P >0.05). At the final follow-up visit, in PEEK group and titanium group VAS of low back pain[(0.8±0.4) points vs (1.0±0.5) points], VAS for leg pain [ (0.7±0.4) points vs (0.8±0.5) points] and ODI [(9.8±1.6)% vs (12.1±1.5)%] were compared with preoperative [ (5.8±1.1) points vs (6.0±1.1)points], [ (7.2±1.7) points vs (7.0±1.6) points], [(68.5±8.9)% vs(66.3±8.2)%] were significantly different( P <0.05). There was no significant difference in VAS scores between the two groups at each postoperative time point ( P >0.05). At 3 months after surgery, there was no difference in ODI between the two groups ( P >0.05). There were significant differences in ODI between PEEK group and titanium rod group at 12 months [(15.5±2.1)% vs (18.4±2.4)%] and at the last follow-up [(9.8±1.6)% vs (12.1±1.5)%] ( P <0.05). The total range of motion (ROM) of lumbar decreased in both groups after surgery. At 12 months after surgery and the last follow-up, the PEEK group compared with the titanium rod group, the total range of motion of lumbar was statistically significant ( P <0.05). The range of motion (ROM) of the fixed segments decreased in both groups after surgery. The ROM of the fixed segments in PEEK group decreased from (9.5±4.6)° to (4.1±1.9)° at the last follow-up ( P <0.05), which in the titanium rod group was decreased from (9.8±4.3)°to (0.9±0.5)° at the last follow-up ( P <0.05). The range of motion (ROM) of upper adjacent segment increased in both groups, there was statistical significance in the ROM of upper adjacent segment between the two groups at 12 months after surgery and the last follow-up, ( P <0.05). There was no screw loosening and broken rods in both groups during the follow-up period., Conclusion: The PEEK rod semi-rigid pedicle screw internal fixation system used in lumbar non-fusion surgery can retain part of the mobility of the fixed segment, showing comparable short-term clinical efficacy to titanium rod fusion. PEEK rod semi-rigid pedicle screw internal fixation system is a feasible choice for the treatment of lumbar spine degenerative diseases, and its long-term efficacy needs further follow-up observation.

Malignant adenomyoepithelioma(MAME)of the breast is a rare tumor with an incidence less than 1% of primary breast cancer.The low incidence and diverse histomorphology pose challenges to the accurate diagnosis and clinical management of MAME.This paper reports a case of MAME of the breast with an intraductal papillary growth pattern and summarizes the clinical features,pathological features,diagnosis,treatment,and prognosis of MAME of the breast in the last 5 years.

Objective To analyze the genetic subtypes of human immunodeficiency virus (HIV) and the prevalence of pretreatment drug resistance in the newly reported HIV-infected men in Guangxi. Methods The stratified random sampling method was employed to select the newly reported HIV-infected men aged≥50 years old in 14 cities of Guangxi from January to June in 2020.The pol gene of HIV-1 was amplified by nested reverse transcription polymerase chain reaction and then sequenced.The mutation sites associated with drug resistance and the degree of drug resistance were then analyzed. Results A total of 615 HIV-infected men were included in the study.The genetic subtypes of CRF01&#95;AE,CRF07&#95;BC,and CRF08&#95;BC accounted for 57.4% (353/615),17.1% (105/615),and 22.4% (138/615),respectively.The mutations associated with the resistance to nucleoside reverse transcriptase inhibitors (NRTI),non-nucleoside reverse transcriptase inhibitors (NNRTI),and protease inhibitors occurred in 8 (1.3%),18 (2.9%),and 0 patients,respectively.M184V (0.7%) and K103N (1.8%) were the mutations with the highest occurrence rates for the resistance to NRTIs and NNRTIs,respectively.Twenty-two (3.6%) patients were resistant to at least one type of inhibitors.Specifically,4 (0.7%),14 (2.3%),4 (0.7%),and 0 patients were resistant to NRTIs,NNRTIs,both NRTIs and NNRTIs,and protease inhibitors,respectively.The pretreatment resistance to NNRTIs had much higher frequency than that to NRTIs (2.9% vs. 1.3%; χ 2 =3.929, P =0.047).The prevalence of pretreatment resistance to lamivudine,zidovudine,tenofovir,abacavir,rilpivirine,efavirenz,nevirapine,and lopinavir/ritonavir was 0.8%, 0.3%, 0.7%, 1.0%, 1.3%, 2.8%, 2.9%, and 0, respectively. Conclusions CRF01&#95;AE,CRF07&#95;BC,and CRF08&#95;BC are the three major strains of HIV-infected men≥50 years old newly reported in Guangxi,2020,and the pretreatment drug resistance demonstrates low prevalence.

To explore the effect and persistent effect of thiolated montmorillonite (TM) on safe production in cadmium (Cd) contaminated cropland, a two-year field experiment was conducted with different application amounts of TM. By adding to highly contaminated soils containing 2.46-3.81 mg·kg -1 Cd with no replenishment, the impacts of TM on concentrations of Cd in different parts of rice and available Cd in soils were investigated. The results showed that TM could significantly reduce the contents of Cd in brown rice as well as the contents and proportions of available Cd in soils, and its persistent effects on the passivation of Cd were obvious. After applying 0.5% or 1% TM to soils, the contents of Cd in different parts of the rice decreased significantly in the first season compared with that in the control. The contents of Cd in brown rice in the first season decreased to 0.16 mg·kg -1 and 0.08 mg·kg -1 , respectively, by 84.0% and 91.9% compared with that of the control (0.98 mg·kg -1 ). Contents of Cd in brown rice were significantly lower than the maximum allowable amount (0.2 mg·kg -1 ) set by China (GB 2762-2017). Under the 0.5% and 1% treatments, the contents of Cd in brown rice of the subsequent three seasons under successive planting decreased by 50.2%-67.8% and 56.0%-81.6%, respectively, which were within the allowable amount. The proportions of available Cd in soils in the first season decreased from 48.4% under the control to 27.9% and 18.4%, respectively, which decreased by 20.5% and 29.9% under the 0.5% and 1% treatments. Compared with that in the control, proportions of available Cd in soils of the following three seasons decreased by 10.0%-17.1% and 12.4%-20.8%. There was a significant positive correlation between available Cd contents in soils and Cd contents in various parts of the rice. TM mainly reduced available Cd contents in soils, then reduced the absorption and accumulation of Cd in rice. The results of the two-year field experiment showed significant and continuous effects of TM on inhibiting Cd uptake by rice, which could be applied to the safe production in heavily Cd contaminated cropland.

Objective To investigate the fine needle aspiration cytology and differential diagnosis of hyalinizing trabecular tumor (HTT) of the thyroid.Methods The fine needle aspiration smears of four HTT cases with histopathological controls were analyzed,which were then combined with the histopathological changes and immunophenotypes for diagnosis.The key points of cytological diagnosis and the differential diagnosis of HTT were then summarized.Results The fine needle aspiration cytology showed that the tumor cells were scattered,presenting as partially cohesive clusters or clusters with trabecular manifestations.The tumor cells were polygonal or spindle,with medium or rich cytoplasm.The nuclei were oval or short spindle,with fine granular chromatin,visible small nucleoli,common nuclear grooves and nuclear pseudoinclusions,and irregular outline,which demonstrated the nucleus characteristics of papillary thyroid carcinoma.The interstitium showed transparent basement membrane-like material deposition,loose tumor cell clusters,trabecular or syncytial structure,radially distributed tumor cells around the hyaline-like material,rich eosinophilic or dichromophile cytoplasm,elongated nuclei,no papillary structure or fibrovascular axis,and no psammoma bodies.Histopathology showed tumor cells arranged in beam and organoid,transparent basement membrane-like material deposition between trabecular beams,and polygonal or spindle cells containing fine granular eosinophilic cytoplasm and round or oval nuclei with common nuclear grooves and nuclear pseudoinclusions.Conclusion Combining the ultrasound results with the arrangement,interstitial components,and cytological characteristics of tumor cells,we suggest that Ki-67(MIB-1)staining can be employed to assist diagnosis and improve the diagnostic accuracy of HTT or intraoperative freezing can be adopted for further diagnosis.

Objective: To explore the risk factors of abdominal aortic enlargement (AAE) after thoracic endovascular aortic repair using two-stent graft implantation (TEVAR-TSI) for Stanford type B aortic dissection., Methods: The clinical and imaging data of patients who underwent TEVAR-TSI for Stanford type B aortic dissection in the First Affiliated Hospital of Hebei North University from January 2013 through September 2020 were retrospectively collected and analyzed. CT angiography (CTA) scans were performed before the procedure. Follow-up CTA scans were scheduled and performed in 1, 3, 6, and 12 months after the procedure and annually thereafter. The primary outcome was AAE. The risk factors of AAE after TEVAR-TSI were selected and survival analysis and multivariate logistic regression were conducted accordingly., Results: A total of 146 patients were regularly followed up at our hospital, with the median followup time of the entire cohort being 48 months (ranging from 12 to 84 months). During the followup period after TEVAR-TSI, the incidence of AAE was 19.9% (29/146). A total of 29 patients developed AAE (the AAE group), while 117 patients did not develop AAE (the non-AAE group). There were a total of 27 deaths, including 13 in the non-AAE group versus 14 in the AAE group. Distal aortic reoperation was performed on 10 patients, including 4 in the non-AAE group versus 6 in the AAE group. The cumulative long-term survival and freedom from distal aortic reoperation of the non-AAE group were both significantly better those of the AAE group ( P <0.05). Logistic multivariate regression analysis showed that independent risk factors of AAE after TEVAR-TSI included the following, partial thrombosis of the false lumen (odds ratio [ OR ]=4.090, 95% confidence interval [ CI ]: 1.539-10.867, P =0.005), the longer cumulative diameter of residual intimal tear above the level of the lowest renal arteries ( OR =1.290, 95% CI : 1.164-1.429, P =0.000), and shorter cumulative diameter of residual intimal tear below the level of the lowest renal arteries ( OR =0.487, 95% CI : 0.270-0.878, P =0.017)., Conclusion: The prognosis of patients who developed AAE after TEVAR-TSI was not good. During followup visits, as precautions against the development of AAE, close attention should be paid to partial thrombosis of the false lumen, cumulative diameter of residual intimal tear above the level of the lowest renal arteries, and cumulative diameter of residual intimal tear below the level of the lowest renal arteries., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).)

Objective: To explore the clinical significance of magnetic resonance imaging water-fat separation (Dixon) technique in patients with multiple myeloma., Methods: A total of 41 newly diagnosed patients with multiple myeloma who underwent Dixon in The Affiliated Hospital of Qingdao University from April 2019 to April 2021 were included in this study. Patients were divided into observation group and control group according to whether Dixon performance was normal or not. The differences of clinical data and fat fraction (FF) between the two groups were compared. The correlation between FF and clinical data, disease stages and differences before and after treatment were also compared. The receiver operator characteristic curve of patients was drawn to analyze the diagnostic value of FF combined with serum alkaline phosphatase for bone destruction in patients with multiple myeloma., Results: Among the 41 patients, there were 12 cases in the control group and 29 cases in the observation group. There was no significant difference in age and sex between the two groups. In the observation group, β2-microglobulin concentration and M protein were significantly higher than those in the control group, while serum alkaline phosphatase and FF were lower (P<0.05). In all 41 patients included in the study, there was a significant negative correlation between FF value and β2-microglobulin concentration (r=-0.57), and a significant positive correlation between FF value and serum alkaline phosphatase (r=0.31). After treatment, FF value increased, while myeloma cell percentage, β2-microglobulin concentration and M protein decreased in 11 patients who completed 4 cycles of chemotherapy, and the differences before and after treatment were statistically significant (P<0.05). The value of serum alkaline phosphatase combined with FF value in predicting bone destruction is higher than that of FF value or serum alkaline phosphatase alone., Conclusion: Dixon's different imaging manifestations can reflect the severity of the disease. FF value is correlated with clinical examination results and R-ISS staging, and there is a significant difference before and after treatment. Serum alkaline phosphatase combined with FF value is better than two indicators alone in predicting bone destruction.

Objective: To investigate the characteristics of aortic remodeling after thoracic endovascular aortic repair using two-stent graft implantation (TEVAR-TSI) for Stanford B aortic dissection., Methods: The clinical and imaging data of 128 patients who underwent TEVAR-TSI for Stanford B aortic dissection in the First Affiliated Hospital of Hebei North University from January 2013 through May 2019 were retrospectively collected. CT images were obtained before (T 0 ) TEVAR-TSI and, 1 week (T 1 ), 3 months (T 2 ), 6 months (T 3 ), 1 year (T 4 ) after TEVAR-TSI. The maximum diameter of the true lumen and false lumen in the short axis view was accessed at five levels: L 1 : the level of primary tear entry, L 2 : the level of the bronchial bifurcation, L 3 : the level of the distal of the first stent-graft, L 4 : the level of the celiac trunk, L 5 : the level of the lowest renal arteries. The false lumen thrombosis in the thoracic aorta and abdominal aorta were assessed at different times, the false lumen and true lumen changes in diameter were evaluated between the preoperative and postoperative CT scan., Results: The stented segment of the descending thoracic aorta was evaluated (L 1 -L 3 ): The true lumen diameter showed an increasing trend and the false lumen diameter showed an decreasing trend at levels L 1 , L 2 , and L 3 , the change of true lumen diameter was positively correlated with the follow-up time ( r =0.721, 0.827, 0.893, P <0.05), and the change rate of true lumen diameter was positively correlated with the follow-up time ( r =0.763, 0.818, 0.902, P <0.05), and the change of false lumen diameter was negatively correlated with the follow-up time ( r =-0.750, -0.927, -0.934, P <0.05), and the change rate of false lumen diameter was negatively correlated with the follow-up time (-0.774, -0.935, -0.952, P <0.05). When the unstented segment of the abdominal aorta was evaluated (L 4 -L 5 ), the average true lumen diameter at the level of celiac trunk increased significantly at 1 year by 13.7% ( P =0.007), however, the average false lumen diameter did not change over time ( P =0.406). The average true lumen diameter and false lumen diameter at the level of the lowest renal arteries increased over time as well, the average true lumen increased by 10.1%, and the average false lumen increased by 13.6% ( P =0.048, 0.017). Besides, the complete false lumen thrombosis rate of the stented segment of the descending thoracic aorta was higher than that of the unstented segment of the abdominal aorta.e complete false lumen thrombosis rate of the stented segment of the descending thoracic aorta was higher than that of the unstented segment of the abdominal aorta., Conclusion: After receiving TEVAR-TSI, Stanford type B aortic dissection patients had high thrombosis absorption rate in the thoracic aortic segment covered by stent, and the aortic remodeling was more ideal. The aortic remodeling effect in the abdominal aortic segment not covered was not ideal, and the inner diameter of the abdominal aorta tended to increase. Therefore, close follow-up monitoring should be conducted., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).)

Objective To explore the relationship among post-traumatic stress disorder(PTSD),social support and quality of life in patients with spinal cord injury(SCI)after a long recovery in China and investigate the factors influencing the quality of life. Methods In this cross-sectional study,206 SCI patients who were hospitalized in 9 hospitals were enrolled.Data collection was performed using general information,the Post-Traumatic Stress Disorder Checklist-Civilian version,the social support scales,and the World Health Organization Quality of Life-Abbreviated version.The data were statistically analyzed using t test,multivariate linear regression,and adjustment effect analysis. Results PTSD was negatively correlated with quality of life( r =-0.337, P <0.001).Social support was positively correlated with quality of life( r =0.318, P <0.001).Social support showed a positive regulatory role between the heightened sense of threat dimension of PTSD and the overall quality of life( β =0.324, P =0.032)or its environmental domain( β =0.227, P =0.004)but showed a negative regulatory effect on the re-experiencing dimension of PTSD and the environmental domain of quality of life( β =-0.125, P =0.017).PTSD,social support,gender,marital status,and economic status were significant predictors of quality of life. Conclusion Reducing PTSD and improving social support can improve long-term quality of life in SCI patients.

Objective: To study the high risk factors for the transformation into acute myeloid leukemia(AML) in patients with intermediate and high risk myelodysplastic syndrome(MDS) treated by decitabine-based regimen., Methods: The clinical characterstics of 60 intermediate and high risk MDS patients and the factors of its transformed into AML were retrospectively analyzed., Results: The overall response rate(ORR) of the patients suffered from intermediate and high risk MDS treated by decitabine-based regimen was 65.0％(39/60), among the 60 cases 17 achieved complete remission(CR), 5 achieved morrow complete remission(mCR), 4 achieved partial remission(PR) and 13 achieved hematologic improvement(HI). Twenty-one cases(35.0%) were transformed into AML among 60 cases of intermediate and high risk MDS treated by decitabine-based regimen. The median time of transformation from intermediate and high risk MDS into AML was 10.0 months(1.6-32.0). χ 2 or Fisher's exact test showed that 2016 WHO MDS diagnostic subgrouping, myeloid hyperplasia markedly active, delayed interval of decitabine-based treatment associated with the transformation from intermediate to high risk MDS into AML (χ 2 =9.878，P=0.031；χ 2 =4.319，P=0.038；χ 2 =6406，P=0.011); Univariate analysis of Kaplan-Meier test showed that 2016 WHO MDS diagnostic subgroups, bone marrow blast cell ratio, bone marrow dysplasia coefficients, prolonged interval of decitabine-based treatment associated with the transformation from intermediate and high risk MDS into AML (P=0.015，P=0.008，P=0.012，P=0.032); multivariate analysis showed the bone marrow blast cell ratio and the bone marrow dysplasia coefficients were independent risk factors for the transformation from intermediate to high risk MDS into AML (P=0.022，P=0.018)., Conclusion: The bone marrow blast cell ratio and the bone marrow dysplasia coefficients are independent risk factors of transformation into AML in the patients with intermediate and high risk MDS treated by decitabine-based regimen. The regular interval of dicitabine treatment is beneficial to maintain the stability of patients conditions.