33 research outputs found

    Niacin downregulates chemokine (c-c motif) ligand 2 (CCL2) expression and inhibits fat synthesis in rat liver cells

    Get PDF
    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, Transfectio

    Optofluidics Refractometers

    No full text
    Refractometry is a classic analytical method in analytical chemistry and biosensing. By integrating advanced micro- and nano-optical systems with well-developed microfluidics technology, optofluidics are shown to be a powerful, smart and universal platform for refractive index sensing applications. This paper reviews recent work on optofluidic refractometers based on different sensing mechanisms and structures (e.g., photonic crystal/photonic crystal fibers, waveguides, whisper gallery modes and surface plasmon resonance), and traces the performance enhancement due to the synergistic integration of optics and microfluidics. A brief discussion of future trends in optofluidic refractometers, namely volume sensing and resolution enhancement, are also offered

    Blood transfusion or hematopoiesis? how to select between the subsidy mode and the long-term mode of eco-compensation

    No full text
    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

    Resource Utilization of Acid Mine Drainage (AMD): A Review

    No full text
    Acid mine drainage (AMD) is a typical type of pollution originating from complex oxidation interactions that occur under ambient conditions in abandoned and active mines. AMD has high acidity and contains a high concentration of heavy metals and metalloids, posing a serious threat to ecological systems and human health. Over the years, great progress has been made in the prevention and treatment of AMD. Remediation approaches like chemical neutralization precipitation, ion exchange, membrane separation processes, and bioremediation have been extensively reported. Nevertheless, some limitations, such as low efficacy, excessive consumption of chemical reagents, and secondary contamination restrict the application of these technologies. The aim of this review was to provide updated information on the sustainable treatments that have been engaged in the published literature on the resource utilization of AMD. The recovery and reuse of valuable resources (e.g., clean water, sulfuric acid, and metal ions) from AMD can offset the cost of AMD remediation. Iron oxide particles recovered from AMD can be applied as adsorbents for the removal of pollutants from wastewater and for the fabrication of effective catalysts for heterogeneous Fenton reactions. The application of AMD in beneficiation fields, such as activating pyrite and chalcopyrite flotation, regulating pulp pH, and leaching copper-bearing waste rock, provides easy access to the innovative utilization of AMD. A review such as this will help researchers understand the progress in research, and identify the strengths and weaknesses of each treatment technology, which can help shape the direction of future research in this area

    An innovative flotation technology for the lime-depressed pyrite recovery from copper sulphide ore via acid mine drainage (AMD) activation

    No full text
    In this study, an innovative flotation technology consisted of Cu differential flotation with high alkali lime and pyrite recovery with acid mine drainage (AMD) activation was investigated for the cleaner beneficiation of the copper sulfide ore. Flotation test results showed that H2SO4 -CuSO4 and AMD could effectively activate the pyrite flotation with SBX collector. Moreover, the recovery of S concentrate is increased by 5.33% in the AMD system. Adsorption amount results of SBX collector indicated that the hydrophilic species (Ca2+, CaOH+ and FeOOH) were formed on the pyrite surfaces in the high alkali lime craft (pH=11.3) and degraded the interaction between SBX and pyrite surfaces. AMD can effectively clear off the hydrophilic calcium species and the copper ions originated from the AMD absorb onto the pyrite surfaces, facilitating the SBX collector adsorption. Composition analysis results of tailings water confirmed that the tailing water obtained by the AMD flotation system was more desirable to be recycled in the Cu differential flotation due to its higher pH value (8.7). The present study provides a novel approach for the treatment of AMD, and has the vital practical significance for the emission reduction of AMD and the increase of beneficiation profits

    Land Cover Classification Based on Fused Data from GF-1 and MODIS NDVI Time Series

    No full text
    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

    Research on Ecological Compensation of National Parks Based on Tourism Concession Mechanism

    No full text
    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

    High-performance room-temperature sodium-sulfur battery enabled by electrocatalytic sodium polysulfides full conversion

    Get PDF
    © 2020 The Royal Society of Chemistry. Room-temperature sodium-sulfur (RT-Na-S) batteries are highly desirable for grid-scale stationary energy storage due to their low cost; however, short cycling stability caused by the incomplete conversion of sodium polysulfides is a major issue for their application. Herein, we introduce an effective sulfiphilic host, gold nanodots decorated on hierarchical N-doped carbon microspheres (CN/Au/S), to achieve completely reversible conversion reactions in the S cathode by electrocatalyzing the low-kinetics conversion of Na2S4 into NaS2 (discharge process) or S (charge process). Besides, gold nanodots and N-doped carbon can increase the conductivity of the S cathode and provide strong polar-polar adsorption of sodium polysulfides to alleviate the shuttling effects. When serving as the cathode, the CN/Au/S composite can realize enhanced sulfur utilization, excellent cycling stability, and outstanding rate capability. This work deepens our understanding of the catalytic effect of gold atoms on sulfur molecules, opening a new avenue for cathode design and development of advanced RT-Na-S batteries

    Forest plot for mean change in BCVA from baseline.

    No full text
    SD indicates standard deviation, CI indicates confidence interval.</p

    Forest plot for forest plot for mean change in TISA 750.

    No full text
    SD indicates standard deviation, CI indicates confidence interval.</p
    corecore