[Construction of green space ecological network in Dongting Lake region with comprehensive evaluation method]. / 基于综合评价法的洞庭湖区绿地生态网络构建.

Green space ecological network is important for improving the fragmentation of regional ecological space, biodiversity loss, imbalance of supply and demand in ecosystem services, and ensuring regional ecology. With Dongting Lake region as an example, the ecological sources were evaluated and identified, and basic ecological resistance of grid element was calculated from the perspectives of comprehensive ecosystem service function evaluation, potential biodiversity comprehensive index evaluation and morphological spatial pattern analysis with the support of 3S technology. We corrected the basic ecological resistance by night light index, used the minimum cumulative resistance model to identify ecological corridors, and constructed a weighted evaluation model, eva-luated the degree of aggregation and dispersion of the sources, as well as the contribution of ecological connection of the corridors. Furthermore, we compared and evaluated the structural characteristic index of the integrated networks, the potential "source sink" networks and the planning networks. The results showed that the spatial distribution of the sources was uneven, with forest land, shrubland and wetland acounting for 95.9% of the total area. The Dongting Lake wetland located in the middle of the region was at high ecological risk. The closer the source was to the center of the ecological network system and the smaller the average minimum cumulative resistance was to other sources, the stronger the advantages of aggregation and dispersion. The denser the distribution of medium and high ecological quality sources was around the high ecological quality sources, the higher the aggregation and dispersion. The closer the corridor was to the high ecological quality sources, the greater contribution of ecological connection. Forest land, shrubland, especially river played an important role in connecting natural ecosystem and human social system. The "source-sink" planning greenways formed a supplement to the "source-sink" potential ecological corridors. Compared with the "source-sink" potential network, the α, ß, γ and ρ index of the integrated network was increased by 123.1%, 25.8%, 26.2% and 74.6% respectively. Compared with the "source-sink" planning network, the α, ß, γ and ρ index was increased by 190.0%, 31.1%, 32.5% and 114.6% respectively. The results could provide reference for the construction of green space ecological network and planning of land use in Dongting Lake region.

[Suitability of human settlement environment in Buyei traditional villages in rocky desertification area of Guizhou, China.] / è´µå·žçŸ³æ¼ åŒ–åŒºå¸ƒä¾æ—ä¼ ç»Ÿæ‘è½äººå± çŽ¯å¢ƒé€‚å®œåº¦.

To investigate the traditional village living environment adaptability to desertification and topography, the suitability evaluation index system and weight of traditional Buyei traditional villages in the rocky desertification area human settlement were quantified using Delphi method and comprehensive weighting method. We calculated human settlements environment suitability value and threshold to comprehensively analyze the human settlements environment suitability. The results showed that 10% of the traditional Buyei traditional villages were located in the rocky desertification areas with high intensity and extremely high intensity and had the tradition of selecting the best environment. The index system of residential environment suitability was composed of five first-level indices (economy, historic culture, ecology, society, and building environment suitability) and 26 second-level indices. This index system was applicable to villages in karst regions. The comprehensive environmental suitability value (2.81-3.77), the economy value (0.77-1.17), the historic culture value (0.39-0.50), the ecology value (0.83-1.07), the social environment value (0.38-0.53) all decreased with the increasing intensity of rocky desertification, but the suitability value of building environment did not change, which ranged from 0.43 to 0.51. Rocky desertification had profound and synergistic impacts on economy, historic culture, ecology and social environment. The floor level of the human settlement suitability threshold was 2.93. If the threshold was lower than 2.93, it could be considered to move or take measures to improve its value. The suitability value (3.56) of traditional village living environment in mountain slope was higher than that in depression (3.42) and valley (3.16). The human settlement suitability of traditional villages in rocky desertification area was higher than that of ordinary villages, but was lower than that of normal landform, with the differences in economy and ecology being the main reasons. To improve the living environment of traditional villages in rocky desertification areas, we should strengthen the comprehensive control of rocky desertification and policy support, develop ecological economy and tourism, protect historic culture or choose ecological migration. This research could provide theoretical base for the planning and construction of village living environment protection in karst areas.

The Diagnostic and Prognostic Value of miR-200c in Gastric Cancer: A Meta-Analysis.

BACKGROUND: The role of miR-200c in gastric cancer remains controversial. This study is aimed at clarifying the diagnostic and prognostic value of miR-200c in gastric cancer through a meta-analysis. METHODS: A comprehensive literature search of PubMed, Embase, and Ovid library databases was conducted. The studies included were those conducted before December 2017. The sensitivity and specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under curve (AUC) were used to estimate the diagnostic value of miR-200c. Meanwhile, the pooled hazard ratio (HR) was used to estimate the prognostic value of miR-200c. RESULTS: For the diagnostic value of miR-200c, six studies that included 202 patients with gastric cancer and 250 normal controls were analyzed. The sensitivity, specificity, PLR, NLR, DOR, and AUC were 0.74, 0.66, 2.20, 0.40, 5.34, and 0.75, respectively. Subgroup analysis showed no significant difference in the type of the sample, method for testing miR-200c, and ethnicity among the patients. Meanwhile, for the prognostic value of miR-200c, seven studies comprising 935 patients with gastric cancer were analyzed. The pooled results showed that miR-200c expression was associated with overall survival (HR = 2.19) and disease-free survival (HR = 1.73), but not with progression-free survival (HR = 1.64) in patients with gastric cancer. There was no publication bias across the studies. CONCLUSIONS: Both serum and tissue miR-200c have moderate diagnostic accuracy in gastric cancer. miR-200c could also be used as a valuable indicator for predicting the prognosis of gastric cancer patients.

[Characteristics of soil mineralizable carbon pool in natural restoration process of Karst forest vegetation].

By the method of taking space instead of time, an incubation test was conducted to study the characteristics of soil mineralizable carbon pool during the natural restoration of Karst forest vegetation in Maolan Nature Reserve, Guizhou Province of Southwest China. It was observed that the contents of soil total organic carbon (TOC) and mineralizable carbon (MC) as well as the carbon mineralization rate decreased with increasing soil depth but increased with the process of vegetation restoration. The amount of cumulative released carbon and the carbon release rate increased with the process of restoration, but the release rate decreased with increasing incubation time. The soil MC/TOC increased with the restoration process but had less change with increasing soil depth, while the qCO2 decreased with increasing soil depth and through the process of restoration. The soil MC had a negative correlation with the existing litter amount (r = -0.796) but positive correlation with the mass loss rate of the litter decomposition (r = 0.924). Soil habitat changed from strong interference at early stages to relative stability at late stages, and soil carbon sequestration changed from small capacity and strong potential at early stages to large capacity and weak potential at late stages.

[Characteristics of soil microbial biomass carbon and soil water soluble organic carbon in the process of natural restoration of Karst forest].

By the method of taking space instead of time, an incubation test was conducted to study the characteristics of soil microbial biomass carbon and water soluble organic carbon in the process of natural restoration of Karst forest in Maolan Nature Reserve, Guizhou Province of Southwest China. The soil microbial biomass carbon content and soil basal respiration decreased with increasing soil depth but increased with the process of the natural restoration, soil microbial quotient increased with increasing soil depth and with the process of restoration, and soil water soluble organic carbon content decreased with increasing soil depth. In the process of the natural restoration, surface soil water soluble organic carbon content increased, while sublayer soil water soluble organic carbon content decreased after an initial increase. The ratio of soil water soluble organic carbon to total soil organic carbon increased with increasing soil depth but decreased with the process of restoration. Soil quality increased with the process of restoration. Also, the quality and quantity of soil organic carbon increased with the process of restoration, in which, soil microbial biomass carbon content had the greatest change, while soil water soluble organic carbon content had less change.

[Changes of foliar delta13C value of Quercus fabric in different root underground habitat types in Karst area].

Selecting the dominant tree species Quercus fabric in three root underground habitat types (the dolomites of low oblique occurrence with multilayer space, middle oblique occurrence with multilayer space, and high oblique occurrence with multilayer space) in Karst area as test object, this paper studied the foliar delta13C value and its correlations with habitat soil conditions, and the plant water use efficiency. There existed remarkable differences in the foliar delta13C value of Q. fabric among the three habitat types, being decreased in the order of low oblique occurrence with multilayer space type (-26.35 per thousand) > high oblique occurrence with multilayer space type (-26.66 per thousand) > middle oblique occurrence with multilayer space type (-27.07 per thousand). Accordingly, the plant water use efficiency decreased in the same order. The foliar delta13C value had significant correlation with habitat soil moisture content, but less correlation with habitat soil elements contents. The delta13C value increased with the decrease of soil moisture content and soil fertility.