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Under the auspices of the national strategies for urban-rural integration and rural revitalization, a focus on the functional evolution and spatial reorganization mechanisms of urban agriculture is of great theoretical and practical significance. This paper analyzes research progress in urban agriculture functional transformation and presents key scientific issues in urgent need of attention in future research. This paper aims to promote high-quality, ecologically sound development of urban agriculture and provides a scientific basis for integrated development of urban and rural areas. We have found that: 1) Research into urban agriculture functional transformation mainly focuses on evaluation and division of urban agriculture development transformation into type models, including multi-functional transformation and sustainable development of urban agriculture, spatial organization and production organization pathways of urban agriculture, land use and bidding mechanisms applied to urban agriculture development, and problems arising from urban agriculture and its multi-dimensional effects. At present, research related to the functional transformation of urban agriculture is guided by the theories of agricultural development, agricultural multi-functionality, and agricultural product demand, focusing on land alienation, ownership security, and diversification of agricultural production subjects in the process of urbanization. 2) The development of urban agriculture presents complex characteristics (i.e., it is multi-subject, multi-linkage, and multi-objective), and coordination of mixed social relations based on the demands of different stakeholders can also pose difficulties. The process and results of the cooperative game of urban agricultural space rental competition and subject interests exert crucial impacts on the restructuring of urban agricultural production system and spatial organization. The dynamic mechanisms of functional evolution and spatial reorganization of regional urban agriculture systems need to be studied. An urgent need exists to strengthen research into land bidding, land tenure, and related stakeholders in urban agriculture development from the perspective of regional systems. It is necessary to clarify the basic and dominant factors influencing the evolution of urban agriculture systems based on different scales, subjects, and perspectives and to elucidate the rent competition mechanism underlying spatial reorganization and ecological and environmental effects. 3) Future research needs to solve key scientific issues regarding three aspects of urban agriculture functional transformation. First, from the perspective of the rural-urban continuum, to clarify the interaction linkage and coupling mechanism between endogenous and external forces driving regional functional evolution in urban agricultural systems. Second, to reveal the key mechanism of spatial restructuring of regional urban agricultural systems and clarify synergies among stakeholders and the logic of land bidding. Third, based on the ecological and environmental impacts of the functional evolution of regional urban agriculture systems and spatial reorganization, comparative studies on the ecological impact of regional functional transformation of agricultural systems at different locations on urban-rural spatial gradient transects are needed.

Owing to the development issues of the Guangdong-Hong Kong-Macao Greater Bay Area in the new domestic and international situation, the content, challenges, and paths of innovation and development of the Greater Bay Area are explored from multiple dimensions, including economic, social, cultural, and institutional. The innovation and development of the Greater Bay Area should strengthen technological and industrial innovation capabilities, improve regional resilience to cope with external shocks, increase the mobility of intraregional factors, improve the well-being of the people's livelihood, enhance the capacity of spatial governance, promote integrated urban-rural development, and optimize the regional pattern of ecological security. The conclusion is that considering the innovation and development of the Greater Bay Area from a systemic and interconnected perspective is crucial for seeking innovations in various development fields and promoting coupling and coordination among them. Therefore, the region may acquire the agency that can continuously break through bottlenecks, resolve external shocks, and unlock new paths of development. We call for the strengthening of cross-field and cross-disciplinary collaborative research to contribute the power of geography to the realization of the development goals of the Guangdong-Hong Kong-Macao Greater Bay Area.

With the continuous advancement of urban renewal, innovative and creative spaces in the urban village have attracted much attention as a new model of space restoration. In the process of material space transformation, the emotional identity and place identity of innovative and creative spaces in urban villages are reconstructed. However, communities and residents in the urban village remain often been neglected in previous studies, most of which focused on the material and economic perspectives. In other words, the emotional mechanisms and spatial influences of relevant subjects in innovative and creative spaces have not received sufficient attention. By focusing on the innovative and creative spaces of Huangpu village in Guangzhou as an example, this study employed in-depth interviews, network text analysis, and other methods to explore the impact of innovative and creative spaces on residents' sense of place and their role in creating a local emotional identity within the context of urban renewal from the perspective of emotional geography. The innovative and creative spaces of the urban villages exerted a different impact on the local emotion and space identity of multiple subjects through the reshaping of the material environment, culture, and social relations. The improvement of the material environment of the innovative and creative spaces in the urban villages enhanced the emotional identity and local attachment of residents. The cultural values of modern industrial forms were not able to shape the local and cultural identities of residents but increased the level of makers. The local identity of the tenant group was based on creativity and cultural atmosphere. The innovative and creative spaces of the urban villages formed a social network relationship with industry as the link by strengthening the interaction and connection between the subjects, establishing a common emotional attachment and local identity, and transforming the original traditional living space into a multi-dimensional space with consumption, production, and leisure attributes. The emotion and atmosphere of the innovative and creative spaces were displayed during the interaction between makers and residents and during the production of creative products and made different subjects participate in the process of space-remodeling. Not only did this process strengthen the perception and recognition of innovative and creative elements and rural areas, but it also established the recognition of a common local value. Given the current emphasis on the reuse of stock space resources, such as industrial heritage and historical buildings, it is particularly important to focus on the emotional connection between humans and the environment. From the perspective of emotional geography, it is of great significance that the emotional effect and meaning of constructing innovative and creative spaces on rural development are elucidated. This study provides not only a theoretical perspective for a deeper understanding of the relationship between the innovative and creative spaces and the locality of urban villages but also insights into promoting culturally oriented urban renewal.

The coordinated development of jobs and housing spaces is of great importance for the rational allocation of urban functions and residents' quality of life. We focus on the measurement of the spatial relationship between working and living space in a mountainous city and the impact of industrial and topographic factors, with the main city of Chongqing as the study area. Using the employed population and residential population as identified by Baidu Huiyan, this paper analyzes the relationship between jobs and housing spaces in the central city of Chongqing by calculating the degree of job-housing deviation, dividing the study area into three groups: the Employment-Dominant Area (EDA), the Balanced Area (BA), and the Residential-Dominant Area (RDA). Factor analysis and window analysis are then applied to explore the impact of industrial and topographic factors on job-housing space based on the Fourth National Economic Census. We find that, first, the spatial distributions of employment and the residential population in the central city of Chongqing are basically the same, showing the characteristics of "high in the middle and low around" and a polycentric spatial structure; there is spatial overlap between the areas with the densest employment and residential population, such as Jiefangbei, Qixinggang, and Nanping. Second, the job-housing space in Chongqing is basically balanced; the deviation of work and residence in most suburban districts is not obvious. The sub-districts with the highest Standard Deviation (SD) are mainly concentrated in the employment-dominant areas within the outer ring, while a few are distributed in the residential-dominant areas. The multi-center structure shows a low job-housing balance in the main center (Jiefangbei) and a high job-housing balance in the four sub-centers. Third, industrial factors and relief amplitude have a great impact on job-housing balance in Chongqing's main urban area. Using SD as the dependent variable can better explain the influencing factors. The integrated service industry factor and the production service industry factor exacerbate the separation of jobs and residences because of their ability to attract the employment population. In the meantime, the social service industry factor, manufacturing factor, and relief amplitude reduce the difference between jobs and residences. In addition, urban spatial structure, traffic patterns, government planning, and residents' attributes are important factors shaping the job-housing space in the Chongqing main area.

Under the background of rural revitalization strategy, art intervention in rural areas, as a new way of rural construction in China, is attracting more and more attention since various art practices have appeared in Chinese villages during the last decade. Art intervention in rural areas has multi-dimensional benefits such as improving rural landscape, promoting villagers' income, enhancing community connections, and promoting cultural inheritance. On the basis of clarifying the connotation and typical modes of art intervention in rural areas in China, this paper constructs and analyzes the benefit hierarchy of art intervention in rural areas based on Maslow's hierarchy of needs theory, and selects Xiaozhou and Fenghe villages in Guangzhou as typical cases to identify the benefit characteristics and problems of two modes of artist-led and capital-led art intervention through field investigation. Although previous studies have focused more on specific cases of art intervention in rural areas, which have revealed the work procedure and achievements in detail, the comparison of their differences and a systematic construction of the influence are still worth discussing. The research results show that: (1) Art intervention in rural areas is a typical mode of rural revitalization in which the government, capital, artists and cultural groups realize multi-level benefits such as rural landscape beautification, tourism economic benefits, community creation and governance, and local cultural inheritance through art practice in the context of rural revitalization. According to different driving subjects, the art intervention in rural areas can be divided into two types: artist-led and capital-led. (2) Art intervention in rural areas has four levels of benefits: material, economic, social and cultural, showing the characteristics of progression by level. (3) The artist-led type plays a significant role in realizing high-level benefits, while the low-level benefits are lacking; the capital-led type plays a significant role in realizing low-level benefits, while the high-level benefits are lacking. (4) Building a multi-party cooperation model with the collaboration of capital and artists, government support, and villagers' participation can combine the advantages of the benefits of the two modes and make the rural practice of art intervention more replicable. In summary, this study divides the practices of art intervention in rural China into two types: artist-led and capital-led, constructs the four-level benefits hierarchy based on Maslow's hierarchy of needs theory, compares the four-level benefits between Xiaozhou village and Fenghe village, and summarizes the benefit differences between the artist-led mode and the capital-led mode. For its contributions, it innovatively applies Maslow's hierarchy of needs theory into the study of art intervention from a theoretical perspective and enriches the case study of art intervention in rural China and explores the characteristics from a practical perspective.

To investigate the impact of climate change on the growth period and yield of irrigated spring maize in arid region of Northwest China, the study was conducted based on located observational experiment and climatic data from 1984 to 2022. The results showed that the temperature increased significantly during the entire growth period with a climate trend rate of 0.76°C•10y-1 (P<0.01), and a significant rise in active accumulated temperature above 10°C, with a climate trend rate of 135.80°C•d•10y-1 (P<0.01). Although there was no significant change in precipitation during the entire growth period, it increased significantly during the milky-maturity stage, with a climate trend rate of 4.50mm•10y-1 (P<0.05). The sunshine duration increased significantly from 1984 to 2004, with a climate trend rate of 126.88h•10y-1 (P<0.01), but decreased significantly in the last 19 years, with a climate trend rate of -109.38h•10y-1 (P<0.01). The growth days of spring maize increased from 1984 to 2004, with a climatic trend rate of 9.86d•10y-1 (P<0.01), but decreased significantly in the last 19 years, with a climatic trend rate of 7.39d•10y-1 . The length of sowing-seedling and seventh leaf-jointing was significantly negatively correlated with temperature, respectively. The length of sowing-seeding, third leaf-seventh leaf and silking-milky was significantly positively correlated (P<0.05) with precipitation, respectively. The length of different growth periods was significantly positively correlated (P<0.01) with sunshine duration, respectively. The yield of spring maize fluctuated and climatic yield was significantly negatively correlated (P<0.05) with precipitation. In summary, climate change has been unfavorable to spring maize growth under current irrigation methods in arid region of northwest China. [ABSTRACT FROM AUTHOR]

Background and purpose: Low-density lipoprotein receptor-related protein 8 (LRP8) plays an important role in the development of liver cancer, lung cancer, breast cancer, colorectal cancer and other tumors. This study aimed to explore the expression and prognostic role of LRP8 in gastric cancer, and evaluate the possibility of a new target for gastric cancer biotherapy. Methods: The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database were used to analyze the expression of LRP8 in gastric cancer tissues. The co-expressed gene with LRP8 in gastric cancer was analyzed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. RNA interference (RNAi) was used for silencing the expression of LRP8 in AGS cell line, and functional assays were performed to evaluate the effects of LRP8 knockdown on the proliferation ability, invasiveness and the Wnt signaling pathway of AGS cell line in vitro. The relationship between LRP8 expression and prognosis of patients with gastric cancer was assessed by using Kaplan-Meier plotter database. To validate the 240 gastric cancer patients from TCGA database results, retrospective immunohistochemical analysis was performed to classify the relationship between the expression of LRP8 and clinical pathological features of 25 gastric cancer patients who underwent total or subtotal gastrectomy from August 2018 to July 2019 in the Fifth Affiliated Hospital of Zhengzhou University. Results: Data from the TCGA database showed LRP8 was overexpressed in gastric cancer tissues compared with normal gastric mucosa (P

Platelet-derived microparticles(PMPs) are extremely small vesicles with complex structure and composition released by platelets, which contain proteins, mRNAs, miRNAs and other bioactive substances and participate in various pathophysiological processes. PMPs promote the development of atherosclerosis(AS) by participating in the processes of vascular endothelial cell injury, inflammatory reaction, lipoprotein deposition, macrophage phagocytosis and plaque instability. Anti-platelet drugs can lower down the plasma level of PMPs. Therefore, PMPs provide a new perspective for the explanation of the pathogenesis and treatment of cardiovascular diseases.

Based on the increasingly severe and complex situation of coal mine safety production, there are still many problems in the basic management of safety production. In order to further improve the level of coal mine safety production management and build an efficient coal mine safety management system, Lu’an Group first proposed the management idea of evaluating the safety management and control ability of coal mine leading group. Lu’an Group, in accordance with the relevant regulations of the superior and in combination with its own characteristic of basic safety management mode, reasonably determines the evaluation items, formulates evaluation and scoring rules, regularly evaluates and assesses the safety management and control ability of the leading group of each mine and analyzes the causes, promotes them to have a deep understanding of their own shortcomings, takes targeted measures to make up for the shortcomings of safety management, continuously improves and perfects working methods, and effectively gives full play to the core leadership role of the team, leads the staff of the whole mine to earnestly perform their post responsibilities, unites and cooperates with each other, concentrates and gathers strength, and pushes forward the work of coal mine safety production.

There have been many difficulties surrounding cumbersome digestion processes and explosive boiling when attempting to detect metal elements in cosmetics. It is difficult to control the pretreatment process and it is necessary to use a lot of reagents, which easily leads to the high reagent blank. Content of lead (Pb) in cosmetics is far below the national limits (≤40 mg/kg), which cannot accurately be determined by flame atomic absorption spectrometric. In this paper a method is described for direct determination of Pb in cosmetics by Graphite Furnace Atomic Absorption Spectrometry with suspension sampling. Sample digestion was not required as the cosmetics samples to be determined were directly placed into the Graphite Furnace Atomic Absorption Spectrometer after suspension by 0.2% nitric acid and 0.1% Triton X-100. The instrument conditions were optimized and high pure argon was added to the drying compressed air in the graphite furnace ashing process, in order to eliminate the carbon residue when the number of samples was over 50, and to ensure the stability for long-term analysis. The matrix modifier was palladium nitrate. Palladium and Pb can form a stable palladium Pb metal compound, and significantly improve the atomic temperature. Standard addition method was conducted to eliminate the matrix interference. The detection limit of this method was 0.003 mg/kg.The recovery of Pb was in the range of 91.6%-106.8%, precision was in the range of 1.5%-2.1% (n=6). National standard reference materials GBW (E) 090028 (cream) and GBW(E) 090027 (powder) were determined by using this method and the results were consistent with the standard value. Compared with the results using the national standard method for detection, the results showed no significant difference. This method has low detection limit, can meet the testing requirements of trace Pb in cosmetics.

[Objectives] To investigate the effect of bleach powder on silkworm intestinal bacteria and digestive enzymes, [Methods] Silkworms were either fed mulberry leaves that had been disinfected with bleach powder or untreated mulberry leaves, and their intestinal bacteria were isolated and identified by 16S rDNA sequencing. [Results] The overall amount of bacteria, and of enzyme-producing bacteria, in the midgut was generally inhibited by bleach powder, regardless of the effective chlorine concentration although there was a positive correlation between the strength of this inhibitory effect and chlorine concentration, Compared to the Control, the abundance of amylase-producing bacteria, as well as the average production of protease, were significantly lower in larvae that had been fed leaves treated with bleach powder, With the exception of the the lowest effective chlorine concentration, 0.3%, exposure to all other concentrations of bleach powder reduced the diversity of mid-gut bacteria to a single genus; Staphylococcus sp., In contrast, the control group and the 0.3% treatment group had relatively diverse enzyme-producing bacteria, including Staphylococcus sp., Lelliottia sp., and Buttiauxella sp. [Conclusion] Both intestinal bacterial community diversity and bacterial digestive enzymes werre significantly inhibited by bleach powder, particularly bacterial protease production and the abundance of amylase-producing bacteria. [ABSTRACT FROM AUTHOR]

Objective The clinical practice intends to evaluate the function of psychological pain management screening tool (DMSM) which has been used on hospitalized patients who suffer psychological pain. To ensure such goal, this practice has used dynamic monitoring and individualized intervention, which have initially built the psychological care management model. Methods From September 2013 to February 2014, 557 cancer patients from the department of thoracic surgery in Chongqing cancer hospital were screened. The patients with psychological suffering were dynamic monitored by the DMSM, recommend by U.S. National Comprehensive Cancer Network, and treated with personalized intervention including psychiatrist consultation weekly. Results Medium psychological pain score of 557 cancer patients was (2.23 ± 1.28) points, among which 76 cases were 3=4 points (13.64%). The average psychological pain scores of discharged 552 cases (except 5 death cases) were (0.12 ± 0.533) points, 6 cases were 3= 4 points (1.09%) (P< 0.01 ). Two depression cases during hospitalization were improved after treatment, no patients suicide. Conclusion Dynamic monitoring and intervention of cancer patients with psychological distress by using DMSM can effectively alleviate the psychological suffering of patients, and detect severe mental disorders of patients at a early stage, help the psychiatrists early intervent to prevent further deterioration, establish suffering - diagnosis - intervention model of psychological screening for cancer patients and provide reference for the clinical management of the effective implementation. [ABSTRACT FROM AUTHOR]

Objective To investigate the antioxidant activity of scutellarin in vitro. Methods The total antioxidant capacity and the scavenging effects on DPPH, superoxide anion and hydroxyl radical of scutellarin were measured by spectrophotometer and microplatereader. Results In vitro, scutellarin significantly increased the clearance rates of ABTS.+, DPPH, superoxide anion and hydroxyl radical. The EC50 values were 64.2, 82.9, 71.6 and 43.3 µmol/L, respectively. Conclusion Scutellarin shows obvious antioxidant effects in vitro. [ABSTRACT FROM AUTHOR]

The change of rural residential land dominates rural land use transformation. Understanding the dynamic change and spatial pattern and developing targeted macro regulating strategy accordingly can provide guidelines for promoting rural land consolidation, rural development and optimizing distribution pattern of towns and villages. In recent years, some studies use single index method especially the net change scale or net change rate, and many of them are on macro perspective. Such method is difficult to depict the complicated types of change for rural residential land. Based on the comprehensive perspective including km-grid, county and province level, this paper used grid data of rural residential land (1 km×1 km) and put forward a new research framework to analyze the quantitative characteristics and to claβify the regional types of rural residential land change. The comprehensive indicator method consisted of total change rate, net change rate and share modifying. Then the spatial autocorrelation analysis method was used to explore the spatial distribution and agglomeration features. Based on the above analysis, regulating strategies for rural residential land were proposed finally. First, all provinces or counties nationwide were claβified into four regional types by the comprehensive indicator method. The increased active regions included 786 counties and districts which mainly distributed in Huang-Huai-Hai plain, northeast plain, Yangtze River delta, Sichuan basin, etc. The increasing and decreasing balanced active regions consisted of 297 counties which was the least among the four types. The decreased active regions involved 352 counties and districts and mainly concentrated in mountain areas and the transition section between plain and mountain area. The final type was named as the changed slowly regions which had 926 counties and districts, accounting the most in the four types, and almost all of them distributed in the western China. Second, compared with single index method, the comprehensive indicator method was able to identify the special types of increasing and decreasing balanced active regions, and avoided the defect that the change rates of some counties might be overestimated or underestimated due to the regional difference of the original scale of rural residential land by share modifying. Therefore, the new method in this paper was more scientific for claβifying change types. Third, the spatial autocorrelation analysis showed that the four types had significant space correlation. The high-high clusters mainly distributed in plains and areas around large cities, and the low-low clusters concentrated in those regions with poor natural and geographical conditions in central and southwest China and the Qinghai-Tibet Plateau. Fourth, each change type should have targeted regulating strategy. The increasing active regions were the core areas for urbanization and rural-urban development transformation, in which the typical feature of rural residential land was rapidly increased. The key point of regulating strategy in those regions was the exited and revitalized mechanism innovation. The increasing and decreasing balanced active regions were the important areas with fertile arable land for protecting national food security. The regulation of rural residential land in those regions should pay attention to improving living conditions and environment for rural residents and promoting rural space reconstruction by land consolidation. The decreasing active regions were the main areas of rural residential land reclamation. The local governments should guide rural population for centralized residence with a moderate scale and should push forward the obsolete housing land reclamation to arable land or woodland. The changed slowly regions were in the most ecologically vulnerable and under developed rural area. Under the preconditions to strictly protect the ecological environment, these regions should combine land consolidation, rural development and village renovation, and then build typical eco-village. [ABSTRACT FROM AUTHOR]

In order to solve the problem of uncertainty factors in the evaluation of blasting, the comprehensive evaluation model of bench blasting effect was established on the base of uncertainty measurement theory. The 12 main factors including the boulder yield, muck pile profile, loose coefficient, fragment distribution, toe rate, back crack distance, blasting vibration, flying distance, environmental impact, explosive consumption, detonator consumption, and blasted volume per meter were selected to act as the index of the uncertain insure model. The uncertainty measurement function was obtained based on the in-situ data. Entropy theory and rules of credible recognition criteria were applied to respectively obtain the index weight of all indexes,and the comprehensive evaluation results of the bench blasting effect. And,the comprehensive evaluation results of the bench blasting effect were finally obtained. The 4 times bench blasting in Hongshuitai field-leveling projects were comprehensively evaluated,and the analysis results are consistent with the actual situations. [ABSTRACT FROM AUTHOR]

Objective To study the effects of JGYS on bone weight, bone mineral density, and bone calcium, and to evaluate the therapeutic effects on ovariectomy (OVX) -induced rat osteoporosis and its dose -- effect relationship. Methods Female Sprague-dawly (SD) rats were randomly divided into an ovariectomized (OVX) group and a sham operation group. The rats in OVX group were ovariectomized. However, for the rats in sham group, only a part of fat near both ovaries were removed under the same anesthesia and surgical approach. Bone mineral density, mechanical properties, and serum biochemical parameters were examined 90 d after OVX to characterize the experimental animal model. After osteoporotic rat model establishment, rats in OVX group were divided into model group, diethylstilbestrol group, 300 mg/kg, 600 mg/kg, 1 200 mg/kg JGYS groups, and 500 mg/kg Xianlingubao capsule, ten rats in each group. All the above drugs were administered orally for 90 d. Bone mineral density and serum biochemical parameters were examined respectively by dual-energy X-ray absorptiometry analysis and enzyme-linked immunoassay. Results (1) Effect on the uterus index: compared with model group, 1200 mg/kg JGYS could obviously reduce the weight of rats, and increase the uterus index; 600 mg/kg JGYS reduced weight and increased the uterus index; 300 mg/kg JGYS had no significant effect on rat weight and the uterus index; the effect on the uterus index of 600 mg/kg JGYS was similar to Xianlingubao capsule, but significantly weaker than diethylstilbestrol. (2) Effect on bone metabolism index: (1) the effect on serum ALP, TRAP: compared with the model group, 600 and 1200 mg/kg JGYS could significantly decrease the activity of ALP and TRAP, 300 mg/kg JGYS had no obvious effect on the activity of ALP and TRAP. The function of 600 mg/kg JGYS was similar to Xianlingubao capsule and diethylstilbestrol. (2) the effect on the blood calcium and blood phosphorus: compared with OVX group, three doses of JGYS showed no significant effect either on blood calcium or on blood phosphorus levels. (3) Effect on bone mass: (1) the effect on femoral bone mineral density and bone mineral content: compared with the model group, 600-1200 mg/kg JGYS groups could significantly increase femoral bone mineral density and bone mineral content;300 mg/kg JGYS showed no significant effect. The effect of increasing femoral bone mineral density and bone mineral content for 600 mg/kg JGYS was same as 500 mg/kg Xianlingubao capsule and 0.03 mg/kg diethylstilbestrol. (2) the effect of vertebral bone mineral density and bone mineral content : three doses of Yishenjiangu tablet obviously increased vertebral bone mineral density and bone mineral content. The effect on increasing the vertebral bone mineral density and bone mineral content was similar to 500 mg/kg Xianlingubao capsule; the 1200 mg/kg JGYS tablet's function for increasing vertebral bone mineral density was better than Xianlingubao capsule. (3) the effect on wet, dry, and ash weight of bone and bone calcium content: compared with the model group, 600 and 1200 mg/kg JGYS significantly increased femoral and vertebral bone calcium content, and increased the content of wet, dry weight and ash weight; 300 mg/kg JGYS had no significant effect on the former index, but increase the calcium and bone of vertebral bone. The function of 600 mg/kg JGYS was similar to 500 mg/kg Xianlingubao capsule, but weaker than 0.03 mg/kg diethylstilbestrol. Conclusion JGYS can modulate bone metabolism and increase bone mass, and shows a therapeutic effect on OVX-induced rat osteoporosis in a dose -- effect manner. [ABSTRACT FROM AUTHOR]

[Objective] The fresh-keeping technology and the change rules of qualities of Guangxi winter Kyoho grapes during storage were studied to provide theoretical references for Guangxi Kyoho grape preservation and fresh-keeping. [Method] Winter Kyoho grape , as the test material, was post-processed by seven freshness keeping (chemical and biological freshness keeping) treatments with non-processing fruit as the control. The qualities indexes of grape fruits were determined every month for 5 continuous times. [Result] The results showed that with the extension of storage period, abscission rate and pH rose, while intact rate decreased constantly. TS (total sugar)content rose first and then fell. TA (titratable acid), TSS (total soluble solids)and Vc content were degradative. Intact rate of chemical freshness treatments was over 85% after 5 months storage, however, it was only 13.66% in the contorl. Contents of TS, TSS and Vc of all fresh-keeping treatments were significantly higher than those of the control at the same period (P< 0.05). Contents of TA of chemical freshness keeping were higher than those of the control. The biological freshness keeping agents could keep good value of grape fruit in a short storage period (0-3months). [Conclusion]Cold storage with freshness keeping agents could effectively maintain the quality of grape fruit and the best storage period of Guangxi winter Kyoho grapes is 0-3 months. [ABSTRACT FROM AUTHOR]

In order to solve problems of serious strata behaviors and deformation of roadway in Shuguang Mine the paper studied the stability of roadway by optimizing grouting parameters and used the combined support of anchor cable and grouting with deep and shallow holes to support weak coal sides of roadway. The results showed that grouting reinforcement in weak coal sides could promote the broken surrounding rock to form a whole structure and improve the self-bearing capacity and reduce the bearing pressure of roadway roof. The grouting combined with deep and shallow holes could close the shallow surrounding rock and form effective tension point of anchor cable in deep surrounding rock. The roadway deformation of grouting in two sides decreased about 50% compared with grouting in one side and decreased about 85% compared with original support method. It could control the global deformation of roadway surrounding rock. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of corilagin on the proliferation and cell cycle of human vascular endothelial cells (HUVEC) stimulated by oxidized low density lipoprotein (ox-LDL), respectively. Methods The model of injured-HUVEC was duplicated by ox-LDL. The effects of corilagin on ox-LDL-stimulated HUVECS were observed by MTT assay. Flow cytometry (FCM) was used to measure the effects of corilagin on the cell cycle. Results Compared with the model group, the proliferation of HUVECs was significantly increased after treated with corilagin at 6.252 µmol/L-50 µmol/L, incubated respectively for 12 h, 24 h and 48 h (P < 0.05). FCM assay result showed the S-phase cell count of ox-LDL-induced-HUVEC group was reducted significantly, and DNA contant of G2-Phase was increased intensively; S-phase cell count of corilagin incubated HUVEC-injured group increased gradually, meanwhile, each phase of the cell ration had scarcely difference with time changing. Conclusion Corilagin may significantly increase the cell viability of HUVECs, and can protect ox-LDL induced-HUVEC from injury by reieving the G2/M phase arrest of cells. [ABSTRACT FROM AUTHOR]

[Objective] The quality evaluation factors of mango fruit were simplified to provide theoretical references for the establishment of mango quality indexes. [Method] Nineteen quality parameters from eighteen varieties of mango fruit in Guangxi areas, including fruit shape index, flesh firmness, contents of total soluble solids, titratable acid (TA), soluble sugar (SS ), flavor, etc, were measured. The data were analyzed by principal component analysis, systematic cluster analysis, and rationalization satisfaction index and the consolidating rule of multidimensional value theory, after which quality evaluation factors of the mango fruit were filtered. [Result] The results showed that there was either relative independence or close correspondence among the characteristics indicators of fruit quality. Seven indicators were selected according to the principal component scores. Based on the above results, 9 indicators for evaluating mango quality were obtained by systematic cluster analysis. Zill No.6, Zihua, Guire No.82, Guire No. 120, and Xiang-mang were selected for better quality varieties. The data of these 9 indicators of all tested fruits were analyzed with rationalization-satisfaction index and the consolidating rule of multidimensional value theory are suitable for selecting evaluation factors for mango fruit quality. [ABSTRACT FROM AUTHOR]

In order to investigate blast wave dynamic mechanism of split-tube charge, here, high-speed schlieren photography equipment was applied to carry out the split-tube charge of the blast wave dynamic experimental study. The split-tube charge explosion schlieren pictures show its blast wave propagation external flow field changes. Comparison blast wave propagation time sequence schlieren photography pictures between double-split tube coupling and decoupling charges, the results show that the split direction blast wave front velocity of double-split tube coupling charge is faster than that velocity of double-split tube decoupling charge, vertical slit direction and both ends of charge of the blast wave propagation are formed due to the interaction of blast wave in the split direction. The blast wave is of abundant species distribution in the whole propagation, double-split tube charge blast wave morphology evolved from a dumbbell-shaped to twins situation. The numerical simulation results of split tube charge detonation wave propagation are consistent basically with the high-speed schlieren photography results. [ABSTRACT FROM AUTHOR]

Organic photovoltaic devices - OPVS, have attracted much attention due to their low cost, light weight, and flexible features. Fullerenes have been regarded as the best choice for the acceptors. Methyl [6, 6] -phenyl-C61-butylate ([60] - PCBM, is known to be the best blending material among these derivatives as acceptor, but the relatively low LUMO level has limited the further improvement of open-circuit voltages. Researches were done to change the structures of fullerenes to achieve high LUMO level and Voc. This review summarizes the methods to achieve high Voc by structure modifying of fullerene derivatives and expound structure-property relationship between the acceptors and photovoltaic devices, which could provide valuable information for future material exploitation. [ABSTRACT FROM AUTHOR]

In order to know the breakdown theory of gas discharge and collect the optical single of needle - plate DC stream discharge in short air gap' we designed this experiment. Use optical fiber' spectrometer and ICCD to compose the optical single collecting system' the ICCD alone can capture the optical phenomenon and it can get the spectrum with the help of spectrometer. The controller of this system adopts outer trigger mode with highspeed trigger pulse to get the images. The experiment analyzes the physical process of the phenomenon in the end. [ABSTRACT FROM AUTHOR]

In order to study the roof movement features of fully-mechanized top coal mining in soft large inclined angle seams, the overlaying strata displacement, roof weighting step and mining pressure appearance were researched by using analogy simulation tests and the field monitoring. The results showed that overlaying strata sinked asymmetry and maximum subsidence decreased with increasing height in the process of mining face. The greatest strength and biggest weakness of mining pressure appearance were upper and lower part, taking on faster in the middle than in the ends. The maximum abutment pressure was in 17~ 25 m ahead the working face, the support strength should be strengthened within 40 m ahead the working face. The test results and field observation were in substantial agreement, which could provide the guidance references to the hydraulic powered support selection. [ABSTRACT FROM AUTHOR]

Roadway surrounding rock have the large and fast deformation in main inclined shaft mudstone zone of Chagannaoer Mine, roadway support is difficult. Combined with expansive soft rock engineering geological conditions of main inclined shaft mudstone zone of Chagannaoer Mine and the roadway deformation characteristics of main inclined mudstone zone, high strength steel tubular confined concrete supports ( STCCS ) support program was designed, in which, the roadway support sections is horseshoe section, the selected main steel tube of STCCS is φ194 mm x 10 mm seamless steel tube, filled with the C40 steel fibre reinforced concrete, assisted metal mesh supporting and concrete sprayed layer supporting. By numerical analysis, the results show, STCCS support programs should be timely imposed after the excavation of the main inclined shaft mudstone the, the high bearing capacity of STCCS can provide powerful support reaction force and limit roadway surrounding rock to the roadway space and ensure the stability of the surrounding rock and the reliability of supporting structure. Meanwhile, by analysis on on-site construction and on-site monitoring, STCCS supporting program is easy to construction, and be able to maintain the stability of soft rock roadway surrounding rock of main inclined shaft. [ABSTRACT FROM AUTHOR]

Blasting design in coal mine tunnel is a complex problem of theory and technology, which is concerned with engineering geology, stability classification of surrounding rocks, sectional shape, gas preservation, mining conditions and rock mechanics. Be aimed at these difficulties above, combining the latest developed computer artificial intelligence with results of theoretical studies and practical experience of coal mine tunnel blasting field, the expert system of blasting designing was studied. Established abundance knowledge base including typical case of blasting, blasting theory, expert experience, industry standards, based on rules and typical case of analogical reasoning, applied production rules and the matching of the reasoning strategies, the expert system optimize coal mining blasting parameters the design. Based on secondary development of CAD, graphics subsystem achieves blasting charts drawn automatically. Application of this system on simulation and optimization designing of actual mining tunnel blasting case illustrated designing result actual situation are beidentical. [ABSTRACT FROM AUTHOR]

With self-designed static-dynamic loading setup which can produce initial static stress and dynamic blasting stress field in the specimen, the behaviors of blast-induced crack in the dynamic-static stress field were studied by caustics experiment and the effect of initial stress field to the blast- induced crack was discussed. Two specimens, one is applied nothing and the other is applied 4-direction pre-compression loading, were studied by caustics. It is established that the pre-compression stress, which is vertical to the crack propagation direction, reduces the stress concentration degree at crack tip and hinders the crack propagation, but the pre-compression stress, which is parallel to the crack propagation direction, has no influence on the crack propagation. [ABSTRACT FROM AUTHOR]

Slotted charge has significant guiding effect on blast energy. Slotted charge was introduced into cut blast, and the idea of "cut to drivage" was put forward. Divided a certain range of central rock part from the surrounding with slotted charge blast. This method avoids the disadvantage of single free surface and great clamping effect. Utilized the blast energy of following boreholes, break the rock and throw the fragment out of cavity. Perform numerical simulation of rectangular cut blast. The energy along kerfs' direction is released in priority, and the peak value of point along kerfs is above 200 MPa, which forms the penetration of cracks. In separate cut blast, the utilization rate of borehole reaches to 97.8%. In full section blast,the average utilization rate of borehole reaches to 96.9%. Field tests validate the feasibility of cut blasting with slotted charge. [ABSTRACT FROM AUTHOR]

Objective To approach clinical effects and safety of needle-medicine therapy combined with psychological therapy in treatment of post-stroke depression. Methods A total of 130 patients with post-stroke depression of this hospital from January 2010 to February 2014 were chosen and divided into the control group (65 patients) who were treated with conventional psychological therapy and the observation group(65 patients) with needle and medicine therapy on the basis of the control group according to random number table sampling. The short-term efficacy, scores of HAMD, ADL, NIHSS, MESS and TESS before and after treatment of both groups were compared. Results The overall response rate in the observation group was higher than that of the control group[93.85% (61/65 )vs. 75.38% (49/65)], whose difference had statistical significance (P<0.05). The scores of HAMD , ADL, NIHSS and MESS after the treatment of the two groups were significantly better than those before the treatment. The difference had statistical significance ( P<0.05). The TESS scores on the 28 d and 42 d after the treatment in the observation group was significantly better than those of the control group, whose difference was statistically significant (P<0.05). Conclusion The needlemedicine therapy combined with psychological therapy in the treatment of post-stroke depression may efficiently release depressive symptoms, improve quality of life, promote neurological functional recovery process and reduce the risk of adverse reaction. [ABSTRACT FROM AUTHOR]

For exploring the influence law of explosive stress wave on invisible cracks in back-blast side of tunnel, the test was carried out by adopting the explosion loading transmission type dynamic caustics system. The experimental results show that, under explosion load, back-blast side existing crack defects in the surrounding rock of adjacent tunnel becomes a main disturbance, and perturbation size is connected with distance between the crack and tunnel and crack length. When crack length is 5 mm and the distance between the crack and tunnel respectively is 2,3,4 and 5 mm, the curves of dynamic stress intensity factor in the process of crack propagation present similar laws, namely after the crack run through the roadway, rapid increases to the first peak, and then ranges up and down at a period of time and finally reduce to zero. The difference is that the duration of the oscillation change in the peak fluctuation and the maximum value gradually decreases, the maximum value of are 1.651, 1.572, 1.419 and 1.346 MN/m3/2, which determine that finally extended displacement of invisible crack far-end corresponds for 25. 197, 16. 378, 10. 236 and 5. 984 mm, which renders as the regular of diminishing. The existence of the distance between the crack and tunnel not only has certain delay effect on the propagation of the crack, but also weakened stress wave energy reaching to crack far-end, and the delay and weakened effects gradually are enhanced with the increase of distance between the crack and tunnel. [ABSTRACT FROM AUTHOR]

In order to more accurately obtain llie coal mine ground stress level and orientation,authors proposed a new method for testing ground stress. The type JHDC-1 stress testing instrument is adopted and can automatically store testing pressure with high frequency and generate the test pressure-time curve. Through the implementation of two pressurized fracturing on a test hole,it can get accurate oil pressure value and its corresponding fracturing equation. Authors adopted the elastic stress concentration theory of round hole, analyzed the conversion relationship between the oil pressure value and its fracturing pressure, and provided the basic principle of three hole crack method for testing ground stress. In addition, authors also gave a detailed description for field test methods and steps. The test method is applicable to various geological conditions and underground environment test,especially suitable for on-site coal mine ground stress test. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the mechanism of icaritin-induced ferroptosis in hepatoma HepG2 cells. By bioinformatics screening, the target of icariin's intervention in liver cancer ferroptosis was selected, the protein-protein interaction(PPI) network was constructed, the related pathways were focused, the binding ability of icariin and target protein was evaluated by molecular docking, and the impact on patients' survival prognosis was predicted and the clinical prediction model was built. CCK-8, EdU, and clonal formation assays were used to detect cell viability and cell proliferation; colorimetric method and BODIPY 581/591 C1 fluorescent probe were used to detect the levels of Fe~(2+), MDA and GSH in cells, and the ability of icariin to induce HCC cell ferroptosis was evaluated; RT-qPCR and Western blot detection were used to verify the mRNA and protein levels of GPX4, xCT, PPARG, and FABP4 to determine the expression changes of these ferroptosis-related genes in response to icariin. Six intervention targets(AR, AURKA, PPARG, AKR1C3, ALB, NQO1) identified through bioinformatic analysis were used to establish a risk scoring system that aids in estimating the survival prognosis of HCC patients. In conjunction with patient age and TNM staging, a comprehensive Nomogram clinical prediction model was developed to forecast the 1-, 3-, and 5-year survival of HCC patients. Experimental results revealed that icariin effectively inhibited the activity and proliferation of HCC cells HepG2, significantly modulating levels of Fe~(2+), MDA, and lipid peroxidation ROS while reducing GSH levels, hence revealing its potential to induce ferroptosis in HCC cells. Icariin was found to diminish the expression of GPX4 and xCT(P&lt;0.01), inducing ferroptosis in HCC cells, potentially in relation to inhibition of PPARG and FABP4(P&lt;0.01). In summary, icariin induces ferroptosis in HCC cells via the PPARG/FABP4/GPX4 pathway, providing an experimental foundation for utilizing the traditional Chinese medicine icariin in the prevention or treatment of HCC.

Objective: To screen better promoters and provide more powerful tools for basic research and gene therapy of hemophilia., Methods: Bioinformatics methods were used to analyze the promoters expressing housekeeping genes with high abundance, so as to select potential candidate promoters. The GFP reporter gene vector was constructed, and the packaging efficiency of the novel promoter was investigated with EF1 α promoter as control, and the transcription and activities of the reporter gene were investigated too. The activity of the candidate promoter was investigated by loading F9 gene., Results: The most potential RPS6 promoter was obtained by screening. There was no difference in lentiviral packaging between EF1 α-LV and RPS6-LV, and their virus titer were consistent. In 293T cells, the transduction efficiency and mean fluorescence intensity of RPS6pro-LV and EF1 αpro-LV were proportional to the lentiviral dose. The transfection efficiency of both promoters in different types of cells was in the following order: 293T>HEL>MSC; Compared with EF1 αpro-LV, RPS6pro-LV could obtain a higher fluorescence intensity in MSC cells, and RPS6pro-LV was more stable in long-term cultured HEL cells infected with two lentiviruses respectively. The results of RT-qPCR, Western blot and FIX activity (FIX∶C) detection of K562 cell culture supernatant showed that FIX expression in the EF1 α-F9 and RPS6-F9 groups was higher than that in the unloaded control group, and there was no significant difference in FIX expression between the EF1 α-F9 and RPS6-F9 groups., Conclusion: After screening and optimization, a promoter was obtained, which can be widely used for exogenous gene expression. The high stability and viability of the promoter were confirmed by long-term culture and active gene expression, which providing a powerful tool for basic research and clinical gene therapy of hemophilia.

Objective: To investigate the effects of a self-designed nutritional preparation on hypothalamic-pituitary-ovarian (HPO) axis function and energy metabolism in female SD rats exposed to intermittent cold. Methods: Female SD rats were divided into control group, cold exposure group and nutritional preparation group. The control group and cold exposure group were given distilled water by daily gavage, and the nutritional preparation group was given nutritional preparation intragastrically. After the treatment, the cold exposure group and nutritional preparation group were exposed to -10℃ in a cabin for 4 h every day. After being treated for 14 days, the serum, uterus and ovary of rats were collected. The serum follicle stimulating hormone (FSH), luteinizing hormone (LH) and other hormone indicators were detected by enzyme-linked immunosorbent assay (ELISA) and colorimetry was used to detect ATPase and other energy metabolism related indicators. Results: Compared with the control group, cold exposure significantly up-regulated the protein expressions of FSHR and LHR, and notably enhanced the activity of Na + -K + -ATPase and Ca 2+ -Mg 2+ -ATPase in ovary and uterus (P<0.05). Nutritional preparation down-regulated the protein expressions of FSHR and LHR, and inhibited the activity of ATPase in ovary and uterus (P<0.05) compared with the cold exposure group. Conclusion: Nutritional preparations can effectively improve the expressions of HPO axis related receptors and abnormal energy metabolism in uterus and ovary caused by intermittent cold exposure.

Thirteen lignans were isolated from 60% ethanol extract of Agrimonia pilosa by column chromatography over silica gel, ODS, and MCI and preparative high performance liquid chromatography(HPLC). Their chemical structures were identified by physiochemical properties and spectral data as(7S,8S)-threo-4,7,9,9'-tetrahydroxy-3,3',5'-trimethoxy-8-O-4'-neolignan(1),(+)-4,9,9'-trihydroxy-3-methoxy-3',7-epoxy-8,4'-oxyneolignan(2), dihydrodehydro-diconiferyl alcohol(3), 4,9,9'-trihydroxy-3,3',5-trimethoxy-4',7-epoxy-8,5'-neolignan(4),(-)-secoisolariciresinol(5), 4,7,9,9'-tetrahydroxy-3,3',5'-trimethoxy-8-O-4'-neolignan(6),(+)-isolariciresinol(7), 4,7,9,9'-tetrahydroxy-3,3'-dimethoxy-8-O-4'-neolignan(8), burselignan(9),(-)-evofolin B(10), icariol A2(11), ciwujiatone(12), and(+)-4″,4-dihydroxy-3,3',3″,3,5,5'-hexamethoxy-7,9';7',9-diepoxy-4,8″;4',8-bisoxy-8,8'-dineolignan-7″,7,9″,9-tetraol(13). Compound 1 was a new compound, and compounds 1-13 were isolated from Agrimonia plant for the first time. This study can enrich the chemical components in A. pilosa and provide material conditions for the follow-up study of its biological activity and the elucidation of its pharmacodynamic substances.

Objective To explore the effect of air temperature on the hospitalization of rural residents with cardiovascular diseases and its lag effect in Dingxi city. Methods The meteorological data and air pollution data of Dingxi city from 2018 to 2019,as well as the daily hospitalization data of rural residents due to cardiovascular diseases,were collected.The distributed lag non-linear models were employed to analyze the relationship between daily mean air temperature and the number of inpatients with cardiovascular diseases.Meanwhile,stratified analysis was carried out according to gender,age,and disease. Results There was a non-linear relationship between air temperature and the number of hospitalized rural residents with cardiovascular diseases in Dingxi city.The exposure-response curve approximated a bell shape.The curves for different cardiovascular diseases appeared similar shapes,with different temperature thresholds.Low temperature(-7 ℃) and moderately low temperature(0 ℃) exhibited a cumulative lag effect on the number of patients hospitalized with cardiovascular diseases.With a cumulative lag of 7 days at -7 ℃ and 14 days at 0 ℃,the RR values peaked,which were 1.121(95% CI =1.002-1.255) and 1.198(95% CI =1.123-1.278),respectively.With a cumulative lag of 14 days at 0 ℃,the RR values were 1.034(95% CI =1.003-1.077) and 1.039(95% CI =1.004-1.066) for the number of hospitalized patients with ischemic heart disease and heart rhythm disorders,respectively.The cumulative lag effects of moderately high temperature(17 ℃) and high temperature(21 ℃) on ischemic heart disease,heart rhythm disorders,and cerebrovascular disease all peaked on that day.Specifically,the RR values at 17 ℃ and 21 ℃ were 1.148(95% CI =1.092-1.206) and 1.176(95% CI =1.096-1.261) for ischemic heart disease,1.071(95% CI =1.001-1.147) and 1.112(95% CI =1.011-1.223) for heart rhythm disorders,and 1.084(95% CI =1.025-1.145) and 1.094(95% CI =1.013-1.182) for cerebrovascular disease,respectively.There was no cumulative lag effect of air temperature on the number of hospitalized patients with heart failure.In addition,stratified analysis showed that low temperature(-7 ℃) and moderately low temperature(0 ℃) affected the number of hospitalized female patients with cardiovascular diseases,and only moderately low temperature(0 ℃) affected males.The cumulative lag effect of high temperature on females was higher than that on males.Air temperature exhibited a stronger impact on female patients than on male patients. Additionally,the population aged<65 years old was more sensitive to low temperature and high temperature than that aged ≥65 years old. Conclusions Air temperature changes increase the hospitalization risk of rural residents with cardiovascular diseases in Dingxi city,which presents a lag effect.The effects of air temperature on patients hospitalized due to cardiovascular diseases varied among different etiologies,genders,and ages.It is necessary to emphasize on the impact of temperature changes on health in residents,especially for key populations such as females,people aged<65 years old,and those with ischemic heart disease.

Objective: To investigate the factors affecting the chronicity of childhood primary immune thrombo-cytopenia (ITP) and compare the efficiency of different first-line treatment regimens., Methods: Children with ITP hospitalized in our hospital from September 2013 to October 2018 were retrospectively analyzed., Results: Three hundred and one children (150 males and 151 females) were included in this study, with a median age of 8 (0.17-17) years old, and 110 (36.5%), 92 (30.6%), and 99 (32.9%) cases were grouped into newly diagnosed, persistent, and chronic ITP, respectively. The median of follow-up was 41.92 (1.07-74.03) months. At the end of the follow-up (October 2019), among the 202 newly diagnosed/persistent ITP children, 79 cases (59 newly diagnosed and 20 persistent ITP) achieved remission within 1 year after initial diagnosis, with a remission rate of 39.3%; 122 cases (50 newly diagnosed and 72 persistent ITP) developed chronic disease, with a chronicity rate of 60.7%; one case underwent splenectomy. In 99 cases with chronic ITP, 5 cases underwent splenectomy. Multivariable logistic regression analysis showed that, the insidious onset of symptoms (OR=3.754, 95%CI: 1.882-7.488, P=0.000) increased the risk of chronicity, while the positive antibody to anti-platelet membrane glycoprotein (OR=0.446, 95%CI: 0.224-0.888, P=0.021) might reduce the risk of chronicity. And no difference was found by the analysis of subtype of anti-platelet membrane glycoprotein (P=0.305). The efficacy of the first-line treatment of intravenous immunoglobulin (IVIG) alone or combined with steroid was better than that of steroid alone (P=0.028, 0.028), however, the efficiency was not significantly different between IVIG alone and combined with steroid (P=0.086)., Conclusion: Insidious onset of symptoms in pediatric ITP increases the risk of chronicity, while the positive titer of anti-platelet membrane glycoprotein may reduce the risk. In the first-line treatment for the newly diagnosed/persistent children. The efficacy of IVIG alone or combined with steroid is better than that of steroid alone.

A reliable gas chromatography-flame ionization detector (GC-FID) method was developed for the accurate determination of trace CO and CO 2 in high concentration of SF 6 . Using a combination of dual Porapak Q chromatographic columns with valve switching, SF 6 was separated from the tested samples and blown out of the detection system, with the aim of ruling out the possibility of conversion column poisoning. Meanwhile, CO and CO 2 were on-line separated and subsequently converted to CH 4 in the presence of a nickel catalyst to increase the sensitivity for the determination of carbon-borne gases. The results showed that neither gas interfered with the determination of the other. Satisfactory linearities were achieved in the range 2-500 μL/L for both CO and CO 2 , with highly accurate and reproducible determination (RSD<2%). The developed GC-FID method is applicable to the determination of gases lodged in high-voltage circuit breakers toward the analysis of trace CO and CO 2 , thus providing a tool for probing the potential breakdown of SF 6 -insulated equipment.