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Purpose To investigate the effect of prolonged sevoflurane (SEV) exposure on differentiation potential and hypoxia tolerance of neural stem cells (NSCs). Materials and methods NSCs were extracted from 15-day fetal mice. After sub-culture, Sevoflurane exposure treatment was performed. Cell cycle were detected by flow cytometry. Western Blot and immunofluorescence assay were used to detect the expression and spatial distribution of Nestin, NSE, GFAP, Oct4, and SOX2; CCK-8 detected cell viability. Cell growth morphology was observed under a microscope. Tunel detected cell apoptosis; the concentration of extracel-lular lactate dehydrogenase (LDH) was determined by ELISA. Results Compared with the control group, the proportion of NSCs in the G2/M phase increased in the Sevoflurane exposure group; our results also suggested the sphere- formation rate decreased significantly, Increased apoptosis and decreased cell viability; Besides, the level of LDH release increased. Conclusion Long-term exposure to sevoflurane (> 8 h) promoted the premature differentiation of NSCs and reduced their pluripotency, reserves, and hypoxia tolerance. This study reveals the reasons underlying damage to the nervous system of young children induced by long-term exposure to sevoflurane from the perspective of CNS reserve cells.

Purpose: To elucidate the role of chemokine (c-c motif) ligand 2 (CCL2) in fat metabolism in hepatocytes. Methods: Following partial hepatectomy, regenerated rat liver cells were isolated and cultured for 24 h were transfected with recombinant plasmid pEGFP-N1-CCL2 using liposomes. Niacin was added to the culture medium to inhibit fat synthesis. CCL2 expression was measured using western blot, while the expression of acly-coa synthetase long chain family 4 (ACSL4) and apolipoprotein E (ApoE) were assessed using real-time PCR. Results: At 12 h after transfection, GFP-positive rates in the pEGFP-N1 and pEGFP-N1-CCL2 transfection groups were 42.4 ± 5.6 % and 45.1 ± 3.5 %, respectively. Expression levels of CCL2 increased over time in pEGFP-N1 transfection group, pEGFP-N1-ccl2 transfection group, and niacin and pEGFP-N1-ccl2 transfection co-treatment group; however, CCL2 expression levels in the niacin and pEGFP-N1-ccl2 transfection co-treatment groups were similar to that of pEGFP-N1 transfection group, which were significantly lower than those of the pEGFP-N1-ccl2 transfection group. Expressionlevel trends of fat-related genes ACSL4 and ApoE were similar to that of CCL2. Conclusion: Niacin downregulates the expression of CCL2, thereby inhibiting lipid synthesis in liver cells. Keywords: Chemokine 2, Niacin, Hepatectomy, Lipid synthesis, Transfection

Food production is the basis for ensuring human survival. Ecological compensation for arable land is important to ensure the sustainable use of arable land and food production. However, how is it possible to set the standard of ecological compensation and how to achieve it scientifically? In this paper, we take China as the study area and link the ecological compensation of arable land with the production, circulation and consumption of three staple foods. The amount of food is converted into the area of arable land needed to produce that food. After calculating the value of ecosystem services that support food production on arable land, the ecological compensation standard is obtained, and the realization mode between regions is constructed. The results show that: (1) the flow of staple foods in China is mainly from north to south and the value of arable land support services provided by northern provinces is greater than that of southern provinces, (2) the province that needs to pay the most ecological compensation for cultivated land is Guangdong Province, with an amount of ¥16.082 billion RMB, and the province that receives the most compensation is Heilongjiang Province, with an amount of ¥21.547 billion RMB, (3) in order to coordinate the collection and distribution of ecological compensation in each province, it is necessary to establish an ecological compensation fund for arable land in the central government. Protecting the ecological status of arable land and ensuring sustainable food production is in the overall interest of the country.

The Chinese government has already proposed to build a nature protected area system composed mainly of national parks and encourages the development of concession operations in national parks. The establishment of a long-term ecological compensation mechanism under the concession mode is of great significance to promoting the harmonious development of man and nature in national parks. This paper selects the Pilot Programs for Shennongjia National Park System (PPSNPS) as the research area and constructs a long-term ecological compensation mechanism under the concession model of tourism back-feeding communities in PPSNPS. Through the questionnaire survey (516 valid questionnaires in 2018), based on the Travel Cost Interval Analysis (TCIA) and Contingent Valuation Method (CVM), the landscape value of the study area is monetized. Combined with the investment cost of concession enterprises, we construct the quantitative distribution ratio of the ecological compensation standard and get the amount of ecological compensation. On this basis, a long-term ecological compensation scheme is constructed. This specific scheme content is as below: on the one hand, Shennongjia National Park Administration (SNPA) is the beneficiary of ecological compensation, and the Shennong Tourism Investment Group Co, Ltd. (STIC) is the provider of ecological compensation; on the other hand, the travel tickets income is the only source of ecological compensation funds (back-feeding funds). Specifically, the landscape value of PPSNPS in 2018 was 604,230.3 × 104 yuan, the input cost of STIC was 140,696 × 104 yuan, the income after deducting tax from tourism tickets was 15,200 × 104 yuan, and the distribution ratio of back-feeding funds is 1:4.29 with the back-feeding funds provided to SNPA from STIC of 12,326.65 × 104 yuan. Through this paper, we know that landscape value monetization can provide ideas for quantitative accounting of the ecological compensation standard for national park tourism concession. In the future, this subject needs more theoretical and practical research on multiple long-term ecological compensation mechanisms.

Background: Bone marrow mesenchymal stem cells (BMSCs) are widely used in many fields such as wound repair, gene delivery, and microenvironment improvement. In some cases, BMSC transplantation requires long-term anesthesia. However, the effects of anesthetics on the characteristics of BMSCs are poorly understood.Methods: In this study, we examined the effect of sevoflurane, a gas anesthetic drug most commonly used in children, on the proliferation, differentiation, and homing potential of BMSCs.Results: Short-term (6 h) sevoflurane exposure had almost no effect on the proliferation, differentiation, and homing of BMSCs. However, long-term (24 h) sevoflurane exposure inhibited the proliferation of BMSCs, accelerated their differentiation into nerve cells, and inhibited their homing potential to damaged vascular endothelial cells and intact glioma cells.Conclusion: Short-term anesthesia with sevoflurane as the main inducer is safe and harmless to BMSCs, but long-term sevoflurane exposure may reduce their repair potential. Therefore, because of the high proportion of BMSCs in children, the application of long-term anesthesia with sevoflurane should be cautious, or more suitable anesthetic drugs are needed.

In order to explore the effects of grazing frequency on functional traits and to test whether Stipa gandis has compensatory photosynthesis during the frequent grazing period, we investigated morphological traits, biomass allocation, photosynthetic traits, and chlorophyll fluorescence parameters of the species in Inner Mongolia, China. The grazing frequency treatments included fencing (T0), grazing in May and July (T1, i.e., two months per year) and grazing from May to September (T2, i.e., continuous five months per year). Results indicate that T1 and T2 treatments did not affect individual biomass, but T2 treatment negatively affected individual size, i.e., plant height, stem length, and leaf length. Physiological traits of S. grandis were significantly affected by grazing, year, and their interaction. In July 2014 (i.e., dry environment and low relative humidity), the photosynthetic rate, transpiration rate and water use efficiency were highest under T2 treatment, which was caused by the increase in stomatal conductance. However, in July 2015 (i.e., wet environment and high relative humidity), the photosynthetic rate and water use efficiency were higher under T1 and T2 treatments, which were caused by the increase in actual quantum efficiency and stomatal conductance. Our results implied that under frequent grazing treatment, S. grandis had small height and efficient compensatory photosynthesis, which promoted its resistance to severe grazing.

The main purpose of this study was to explore the dynamic changes of greenhouse gas (GHG) from grasslands under different degradation levels during the growing seasons of Inner Mongolia, China. Grassland degradation is associated with the dynamics of GHG fluxes, e.g., CO2, CH4 and N2O fluxes. As one of the global ecological environmental problems, grassland degradation has changed the vegetation productivity as well as the accumulation and decomposition rates of soil organic matter and thus will influence the carbon and nitrogen cycles of ecosystems, which will affect the GHG fluxes between grassland ecosystems and the atmosphere. Therefore, it is necessary to explore how the exchanges of CO2, CH4 and N2O fluxes between soil and atmosphere are influenced by the grassland degradation. We measured the fluxes of CO2, CH4 and N2O in lightly degraded, moderately degraded and severely degraded grasslands in Inner Mongolia of China during the growing seasons from July to September in 2013 and 2014. The typical semi-arid grassland of Inner Mongolia plays a role as the source of atmospheric CO2 and N2O and the sink for CH4. Compared with CO2 fluxes, N2O and CH4 fluxes were relatively low. The exchange of CO2, N2O and CH4 fluxes between the grassland soil and the atmosphere may exclusively depend on the net exchange rate of CO2 in semi-arid grasslands. The greenhouse gases showed a clear seasonal pattern, with the CO2 fluxes of –33.63 –386.36 mg/(m•h), CH4 uptake fluxes of 0.113–0.023 mg/(m•h) and N2O fluxes of –1.68 –19.90 μg/(m•h). Grassland degradation significantly influenced CH4 uptake but had no significant influence on CO2 and N2O emissions. Soil moisture and temperature were positively correlated with CO2 emissions but had no significant effect on N2O fluxes. Soil moisture may be the primary driving factor for CH4 uptake. The research results can be in help to better understand the impact of grassland degradation on the ecological environment.

Environmental degradation influences carbon (C) cycling and storage in grassland ecosystems by altering vegetation productivity. However, the impacts of different degradation intensities on vegetation–soil C distributions in grasslands have not been well documented. We measured C storage in soil, roots, and plants under light, moderate, and severe degradation levels in a typical steppe region of Xilinhot, Inner Mongolia, China in 2011 and 2012. Grassland C storage was highest in soil, followed by roots, and then aboveground plant biomass. Grassland degradation and precipitation significantly influenced C storage distributions. During the dry year (2011), total C storage in vegetation and soil was highest under light degradation. Carbon storage in aboveground plant biomass and roots increased with degradation intensity. During the wet year (2012), C storage was highest in aboveground plant biomass and roots under light degradation. Root biomass tended to be concentrated in the soil surface during the wet year.

This paper presents some preliminary results to reveal inherent characteristics of short-term voltage dynamics based on a relatively new conception called mixed monotone decomposition. An approximate linear dynamic system is established firstly by using Dommel-Sato iterative method and linearization techniques to differential algebraic equations. Then mixed monotone systems and mixed monotone decomposition conceptions are introduced. Furthermore, we use a three-machine test system to demonstrate the concept of mixed monotone, which are helpful to promote further qualitative analysis and improve control performance.

As a long-term mechanism for eco-compensation, the ‘Hematopoiesis-Compensation Policy’ (HCP) such as industrial transformation can effectively improve the operability and efficiency of compensation policy. However, compared with the ‘Transfusion-compensation Policy’ (TCP) such as the cash subsidy, can HCP quickly achieve the goal of eco-compensation? Does HCP require more total investment in compensation funds? This paper takes the Shennongjia National Park System Pilot Zone (SNJNP) as the research area and takes the eco-compensation policy to encourage farmers to return farmland to forest as the research object. We set three different compensation modes of TCP and HCP, and study the compensation scenarios in the next 20 years. The results show that HCP can achieve the purpose of compensation faster than TCP. Although the annual payment of HCP is relatively higher at the beginning, both the annual expenditure and the cumulative expenditure will decrease significantly. Therefore, later annual expenditure and cumulative total expenditure of HCP will be lower than TCP.

In this study, we study the distributed resource allocation problem over undirected network in smart grid with continuous-time communication. Each generator is accompanied by one private convex objective function. Furthermore, all generators are required to converge to the global optimal solution through cooperation. Therefore, a fully gradient-based decentralized method is designed to deal with the above optimization issue. Furthermore, a constant step-size control gain of gradient is given, which can ensure the achievement of the global optimizer. Moreover, a sufficient condition is presented, which guarantees that above designed algorithm can obtain the global optimal solution. At last, we present an application simulation of resource allocation problem in smart grid to explain the feasibility for above proposed algorithm.

This paper considers a framework of electrical cyber-physical systems. Each bus and branch in a power grid is equipped with a controller and a sensor so that we can monitor and adjust the state of the grid. Recur to measuring the damages of disconnection fault, three kinds of generator output adjustment algorithms are proposed if there are cascading failures or splitting incidents. We compare the final results under the same initial fault based on these three adjustment algorithms then define the performance of these algorithms.

Accurate regional and global information on land cover and its changes over time is crucial for environmental monitoring, land management, and planning. In this study, we selected Fengning County, in China’s Hebei Province, as a case study area. Using satellite data, we generated fused normalized-difference vegetation index (NDVI) data with high spatial and temporal resolution by utilizing the STARFM algorithm to produce a fused GF-1 and MODIS NDVI dataset. We extracted seven phenological parameters (including the start, end, and length of the growing season, base value, mid-season date, maximum NDVI, seasonal NDVI amplitude) from a fused NDVI time-series after reconstruction using the TIMESAT software. We developed four classification scenarios based on different combinations of GF-1 spectral features, the fused NDVI time-series, and the phenological parameters. We then classified the land cover using a support vector machine and analyzed the classification accuracies. We found that the proposed method achieved satisfactory classification results, and that the combination of the fused NDVI data with the extracted phenological parameters significantly improved classification accuracy. The classification accuracy based on the composited GF-1 multi-spectral bands combined with the phenological parameters was the highest among the four scenarios, with an overall classification accuracy of 88.8% and a Kappa coefficient of 0.8714, which represent increases of 9.3 percentage points and 0.1073, respectively, compared with GF-1 spectral data alone. The producer’s and user’s accuracy for different land cover types improved, with a few exceptions, and cropland and broadleaf forest had the largest increase.

Time varying linear differential equations of second order can been transformed into the solvability of time-varying linear differential equations of second order by employing reversible constant linear transformation and reversible time varying linear transformation. The solvability of time-varying linear differential equations of second order is studied, and some sufficiency conditions are presented. Finally, two examples are given to illustrate the theoretical results.

Feature detection is an important point in picture process. The results of its detection will affect pattern recognition and classification directly. Based on Radon transform and wavelet transform detection , linear edges detection method based on Ridgelet transform are put forward in this thesis. With this method, All straight lines are detected and their locations are relatively precise.