Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly ...Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly field surveys. The Swan Goose(Anser cygnoides), a vulnerable Anatidae species, winters almost exclusively in China's Yangtze River floodplain, but wintering numbers have been steadily decreasing. To better safeguard this unique species, modern modeling approaches can be used to quantify and predict its suitable wintering habitat. Specifically, a potential wintering distribution map of this species is critically important.Methods: This study used the maximum entropy approach to model a distribution map of this species. In total, data from 97 up-to-date sites were extracted from 1263 survey sites(excluding duplicate data). After eliminating spatial autocorrelation, 11 environmental variables, including factors related to climate, land structure, vegetation, and anthropogenic activities, were used for model prediction.Results: The prediction distribution map shows that the population has concentrated mainly in the boundary area of Anhui, Hubei, and Jiangxi provinces, especially along the Yangtze River. Modeling results suggest that areas within the middle and lower Yangtze River floodplain, such as those in Hunan and Hubei provinces and the eastern coastal area of Zhejiang Province, demonstrate a potential level of "medium" suitability for this species to winter.Conclusions: Results from this study provide fundamental information for the restoration and management of the Swan Goose. Our "visualized" potential distribution map can assist in planning optimal conservation strategies, and consequently may help to increase the number of wintering populations in China.展开更多
Synthesis of a novel series of N-pyrandione substituted amino acids and their esters 3 via a condensation reaction between pyrandione and amino acid or their derivatives in excess ethyl orthoformate without solvent is...Synthesis of a novel series of N-pyrandione substituted amino acids and their esters 3 via a condensation reaction between pyrandione and amino acid or their derivatives in excess ethyl orthoformate without solvent is described. The stereochemistry of 3 has been discussed.展开更多
The application of nanotechnologies in formulation has significantly promoted the development of modern medical and pharmacological science, especially for nanoparticle-based drug delivery, bioimaging, and theranostic...The application of nanotechnologies in formulation has significantly promoted the development of modern medical and pharmacological science, especially for nanoparticle-based drug delivery, bioimaging, and theranostics. The advancement of engineering particle design and fabrication is largely supported by a better understanding of how their apparent characteristics(e.g., size and size distribution, surface morphology, colloidal stability, chemical composition) influence their in vivo biological performance, which raises an urgent need for practical nanoformulation methods. Based on turbulent flow mixing and the self-assembly of molecules in fluids, flash technologies emerged as effective bottom-up fabrication strategies for effective nanoformulation. Among the flash technology family, flash nanocomplexation(FNC) is considered a novel and promising candidate that can promote and optimize formulation processes in a precise spatiotemporal manner, thus obtaining excellent fabrication efficiency, reproducibility and expandability. This review presents an overview of recent advances in fabricating drug-delivery nanoparticles using FNC platforms. Firstly, brief introductions to the basic principles of FNC technology were carried out, followed by descriptions of turbulent microvolume mixers that have significantly promoted the efficiency of FNC-based fabrications. Applications of real formulation cases were then categorized according to the self-assembly-driven interactions(including electrostatic interaction, coordination interaction,hydrogen bonding and hydrophobic interaction) and discussed to reveal the progressiveness of fabricating nanoparticles and discuss how its flexibility will provide advances and replenish the philosophy of nanomedicine formulation. In the end, the commercial potential, current limitations, and prospects of FNC technology for nanoformulation will be summarized and discussed.展开更多
Background: The efficacy and safety of telmisartan combined with clopidogrel, leflunomide, or both drugs for immunoglobulin A nephropathy (IgAN) are unclear. This study was designed to evaluate the efficacy and saf...Background: The efficacy and safety of telmisartan combined with clopidogrel, leflunomide, or both drugs for immunoglobulin A nephropathy (IgAN) are unclear. This study was designed to evaluate the efficacy and safety of telmisartan combined with clopidogrel, leflunomide, or both drugs for IgAN. Methods: It is a multicenter, prospective, double-dummy randomized controlled trial. Primary IgAN patients were recruited in 13 renal units across Beijing, China, from July 2010 to June 2012. After a 4-week telmisartan (80 mg/d) wash-in, 400 patients continuing on 80 mg/d telmisartan were randomly assigned to additionally receive placebo (Group A), 50 mg/d clopidogrel (Group B), 20 mg/d leflunomide (Group C), or 50 mg/d clopidogrel and 20 mg/d leflunomide (Group D). The 24-week intervention was completed by 360 patients. The primary endpoint was change in 24-h proteinuria at 24 weeks. A linear mixed-effect model was used to analyze the changes at 4, 12, and 24 weeks. Generalized estimating equations were used to evaluate changes in hematuria grade. This trial was registered at the Chinese Clinical Trial Registry. Results: The effects oftelmisartan combined with leflunomide on changes in proteinuria (0.36 [95% confidence interval (CI) 0.18 0.55] g/d, P 〈 0.001), in serum uric acid (76.96 [95% CI 57.44-96.49] μmol/L, P 〈 0.001), in serum creatinine (9.49 [95% CI 6.54-12.44]μmol/L, P 〈 0.001), and in estimated glomerular filtration rate (-6.72 [95% CI-9.46 to -3.98] ml.min -1. 1.73 m -2, p 〈 0.001) were statistically significant, whereas they were not statistically significant on changes in systolic and diastolic blood pressure and weight (P 〉 0.05).Telmisartan combined with clopidogrel had no statistical effect on any outcome, and there was no interaction between the interventions. No obvious adverse reactions were observed. Conclusions: Telmisartan combined with leflunomide, not clopidogrel, is safe and effective for decreasing proteinuria in certain IgAN patients.展开更多
La2Ce2O7 (LCO) is a promising candidate for thermal barrier coatings (TBCs) due to that it provides better thermal insulation than yttria-stabilized zirconia (YSZ) does. In this work, a TBC LCO was produced by solutio...La2Ce2O7 (LCO) is a promising candidate for thermal barrier coatings (TBCs) due to that it provides better thermal insulation than yttria-stabilized zirconia (YSZ) does. In this work, a TBC LCO was produced by solution precursor plasma spraying (SPPS). After the solution precursors were prepared and the spraying parameters were optimized, the thermophysical properties and thermal shock performance of the coatings were tested. It was found that the SPPS coating with segmentation crack density of 6 mm^-1 had the porosities of about 33.5% at spray distances of 35 mm. The thermal conductivity of the SPPS coatings is 0.50-0.75 W·m^-1·K^-1, much lower than that of the atmospheric plasma spraying (APS) coatings (0.85-1.25 W·m^-1·K^-1). The thermal shock performance of the SPPS coatings reached 60 cycles, much better than the APS coatings. This improvement is due to the segmentation cracks in the coatings, which can improve strain tolerance and effectively relieve internal stress. This study provides reference significance for further research on thermal barrier coatings.展开更多
The nano-Ag paste consisted of Ag nanoparticles and organic solvents.These organics would be removed by evaporation or decomposition during sintering.When the sintering temperature was 300℃,the resistivity of sintere...The nano-Ag paste consisted of Ag nanoparticles and organic solvents.These organics would be removed by evaporation or decomposition during sintering.When the sintering temperature was 300℃,the resistivity of sintered bulk was 8.35×10^-6Ωcm,and its thermal conductivity was 247 W m^-1 K^-1.The Si/SiC chips and direct bonding copper(DBC)substrates could be bonded by this nano-Ag paste at low temperature.The bonding interface,sintered microstructure and shear strength of Si/SiC chip attachment were investigated by scanning electron microscopy,transmission electron microscopy and shear tests.Results showed that the sintered Ag layer was porous structure and tightly adhered to the electroless nickel immersion gold surface of DBC substrate and formed the continuous Ag–Au interdiffusion layer.The shear strength of Si and SiC chip attachments was higher than 35 MPa when the sintering pressure was 10 MPa.The fracture occurred inside the sintered Ag layer,and the fracture surface had obvious plastic deformation.展开更多
Summary What is already known on this topic?Starting in the early 1950s,the main industries in China associated with chronic benzene poisoning(CBP)included painting,pharmaceuticals,and shoemaking.However,because of ra...Summary What is already known on this topic?Starting in the early 1950s,the main industries in China associated with chronic benzene poisoning(CBP)included painting,pharmaceuticals,and shoemaking.However,because of rapid socioeconomic development,the distribution of industries associated with CBP likely changed.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.31370416 and 31500315)the State Key Laboratory of Urban and Regional Ecology,Chinese Academy of Sciences(No.SKLURE2013-1-05)the China Biodiversity Observation Network(Sino BON)
文摘Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly field surveys. The Swan Goose(Anser cygnoides), a vulnerable Anatidae species, winters almost exclusively in China's Yangtze River floodplain, but wintering numbers have been steadily decreasing. To better safeguard this unique species, modern modeling approaches can be used to quantify and predict its suitable wintering habitat. Specifically, a potential wintering distribution map of this species is critically important.Methods: This study used the maximum entropy approach to model a distribution map of this species. In total, data from 97 up-to-date sites were extracted from 1263 survey sites(excluding duplicate data). After eliminating spatial autocorrelation, 11 environmental variables, including factors related to climate, land structure, vegetation, and anthropogenic activities, were used for model prediction.Results: The prediction distribution map shows that the population has concentrated mainly in the boundary area of Anhui, Hubei, and Jiangxi provinces, especially along the Yangtze River. Modeling results suggest that areas within the middle and lower Yangtze River floodplain, such as those in Hunan and Hubei provinces and the eastern coastal area of Zhejiang Province, demonstrate a potential level of "medium" suitability for this species to winter.Conclusions: Results from this study provide fundamental information for the restoration and management of the Swan Goose. Our "visualized" potential distribution map can assist in planning optimal conservation strategies, and consequently may help to increase the number of wintering populations in China.
基金the National Natural Science Foundation of China for the project support (No.29832050)
文摘Synthesis of a novel series of N-pyrandione substituted amino acids and their esters 3 via a condensation reaction between pyrandione and amino acid or their derivatives in excess ethyl orthoformate without solvent is described. The stereochemistry of 3 has been discussed.
基金supported by the Sanya Yazhou Bay Science and Technology City (No. 2021JJLH0037)Taishan Scholar Foundation of Shandong Province (No. tsqn202211065)+2 种基金Natural Science Foundation of China (No. 82003673)Yangcheng Scholars Research Project of Guangzhou (No. 20183197)Guangzhou Science and Technology Plan (No. 201901010170)
文摘The application of nanotechnologies in formulation has significantly promoted the development of modern medical and pharmacological science, especially for nanoparticle-based drug delivery, bioimaging, and theranostics. The advancement of engineering particle design and fabrication is largely supported by a better understanding of how their apparent characteristics(e.g., size and size distribution, surface morphology, colloidal stability, chemical composition) influence their in vivo biological performance, which raises an urgent need for practical nanoformulation methods. Based on turbulent flow mixing and the self-assembly of molecules in fluids, flash technologies emerged as effective bottom-up fabrication strategies for effective nanoformulation. Among the flash technology family, flash nanocomplexation(FNC) is considered a novel and promising candidate that can promote and optimize formulation processes in a precise spatiotemporal manner, thus obtaining excellent fabrication efficiency, reproducibility and expandability. This review presents an overview of recent advances in fabricating drug-delivery nanoparticles using FNC platforms. Firstly, brief introductions to the basic principles of FNC technology were carried out, followed by descriptions of turbulent microvolume mixers that have significantly promoted the efficiency of FNC-based fabrications. Applications of real formulation cases were then categorized according to the self-assembly-driven interactions(including electrostatic interaction, coordination interaction,hydrogen bonding and hydrophobic interaction) and discussed to reveal the progressiveness of fabricating nanoparticles and discuss how its flexibility will provide advances and replenish the philosophy of nanomedicine formulation. In the end, the commercial potential, current limitations, and prospects of FNC technology for nanoformulation will be summarized and discussed.
文摘Background: The efficacy and safety of telmisartan combined with clopidogrel, leflunomide, or both drugs for immunoglobulin A nephropathy (IgAN) are unclear. This study was designed to evaluate the efficacy and safety of telmisartan combined with clopidogrel, leflunomide, or both drugs for IgAN. Methods: It is a multicenter, prospective, double-dummy randomized controlled trial. Primary IgAN patients were recruited in 13 renal units across Beijing, China, from July 2010 to June 2012. After a 4-week telmisartan (80 mg/d) wash-in, 400 patients continuing on 80 mg/d telmisartan were randomly assigned to additionally receive placebo (Group A), 50 mg/d clopidogrel (Group B), 20 mg/d leflunomide (Group C), or 50 mg/d clopidogrel and 20 mg/d leflunomide (Group D). The 24-week intervention was completed by 360 patients. The primary endpoint was change in 24-h proteinuria at 24 weeks. A linear mixed-effect model was used to analyze the changes at 4, 12, and 24 weeks. Generalized estimating equations were used to evaluate changes in hematuria grade. This trial was registered at the Chinese Clinical Trial Registry. Results: The effects oftelmisartan combined with leflunomide on changes in proteinuria (0.36 [95% confidence interval (CI) 0.18 0.55] g/d, P 〈 0.001), in serum uric acid (76.96 [95% CI 57.44-96.49] μmol/L, P 〈 0.001), in serum creatinine (9.49 [95% CI 6.54-12.44]μmol/L, P 〈 0.001), and in estimated glomerular filtration rate (-6.72 [95% CI-9.46 to -3.98] ml.min -1. 1.73 m -2, p 〈 0.001) were statistically significant, whereas they were not statistically significant on changes in systolic and diastolic blood pressure and weight (P 〉 0.05).Telmisartan combined with clopidogrel had no statistical effect on any outcome, and there was no interaction between the interventions. No obvious adverse reactions were observed. Conclusions: Telmisartan combined with leflunomide, not clopidogrel, is safe and effective for decreasing proteinuria in certain IgAN patients.
基金financially supported by the National Natural Science Foundation of China (Nos. 51571002 and 51401003)Beijing Municipal Natural Science Foundation(Nos. 2172008 and KZ201310005003)
文摘La2Ce2O7 (LCO) is a promising candidate for thermal barrier coatings (TBCs) due to that it provides better thermal insulation than yttria-stabilized zirconia (YSZ) does. In this work, a TBC LCO was produced by solution precursor plasma spraying (SPPS). After the solution precursors were prepared and the spraying parameters were optimized, the thermophysical properties and thermal shock performance of the coatings were tested. It was found that the SPPS coating with segmentation crack density of 6 mm^-1 had the porosities of about 33.5% at spray distances of 35 mm. The thermal conductivity of the SPPS coatings is 0.50-0.75 W·m^-1·K^-1, much lower than that of the atmospheric plasma spraying (APS) coatings (0.85-1.25 W·m^-1·K^-1). The thermal shock performance of the SPPS coatings reached 60 cycles, much better than the APS coatings. This improvement is due to the segmentation cracks in the coatings, which can improve strain tolerance and effectively relieve internal stress. This study provides reference significance for further research on thermal barrier coatings.
基金financially supported by the National Key Research and Development Program of China(No.2017YFB1104900)the China Postdoctoral Science Foundation(No.2019M650425)。
文摘The nano-Ag paste consisted of Ag nanoparticles and organic solvents.These organics would be removed by evaporation or decomposition during sintering.When the sintering temperature was 300℃,the resistivity of sintered bulk was 8.35×10^-6Ωcm,and its thermal conductivity was 247 W m^-1 K^-1.The Si/SiC chips and direct bonding copper(DBC)substrates could be bonded by this nano-Ag paste at low temperature.The bonding interface,sintered microstructure and shear strength of Si/SiC chip attachment were investigated by scanning electron microscopy,transmission electron microscopy and shear tests.Results showed that the sintered Ag layer was porous structure and tightly adhered to the electroless nickel immersion gold surface of DBC substrate and formed the continuous Ag–Au interdiffusion layer.The shear strength of Si and SiC chip attachments was higher than 35 MPa when the sintering pressure was 10 MPa.The fracture occurred inside the sintered Ag layer,and the fracture surface had obvious plastic deformation.
基金by the Project of Occupational Health Risk Assessment and National Occupational Health Standard Formulation of National Institute of Occupational Health and Poison Control(Project No.:131031109000150003).
文摘Summary What is already known on this topic?Starting in the early 1950s,the main industries in China associated with chronic benzene poisoning(CBP)included painting,pharmaceuticals,and shoemaking.However,because of rapid socioeconomic development,the distribution of industries associated with CBP likely changed.