Remote sensing is a valuable and effective tool for monitoring and estimating aboveground biomass (AGB) in large areas.The current international research on biomass estimation by remote sensing technique mainly focu...Remote sensing is a valuable and effective tool for monitoring and estimating aboveground biomass (AGB) in large areas.The current international research on biomass estimation by remote sensing technique mainly focused on forests,grasslands and crops,with relatively few applications for desert ecosystems.In this paper,Landsat Thematic Mapper (TM)/Enhanced Thematic Mapper Plus (ETM+) images from 1988 to 2007 and the data of 283 AGB samples in August 2007 were used to estimate the AGB for Mu Us Sandy Land over the past 30 years.Moreover,temporal and spatial distribution characteristics of AGB and influencing factors of climate and underlying surface were also studied.Results show that:(1) Differences of correlations exist in the fitted equations between AGB and different vegetation indices in desert areas.The modified soil adjusted vegetation index (MSAVI) and soil adjusted vegetation index (SAVI) show relatively higher correlations with AGB,while the correlation between normalized difference vegetation index (NDVI) and AGB is relatively lower.Error testing shows that the AGB-MSAVI model established can be used to accurately estimate AGB of Mu Us Sandy Land in August.(2) AGB in Mu Us Sandy Land shows the fluctuant characteristics over the past 30 years,which decreased from the 1980s to the 1990s,and increased from the 1990s to 2007.AGB in 2007 had the highest value,with a total AGB of 3.352×106 t.Moreover,in the 1990s,AGB had the lowest value with a total AGB of 2.328×106 t.(3) AGB with relatively higher values was mainly located in the middle and southern parts of Mu Us Sandy Land in the 1980s.AGB was low in the whole area in the1990s,and relatively higher AGB values were mainly located in the southern parts of Uxin.In 2007,AGB in the whole area was relatively higher than those of the last twenty years,and higher AGB values were mainly located in the northern,western and middle parts of Mu Us Sandy Land.展开更多
To investigate the effect of supersaturation induced by micelle formation during dissolution on the bioavailability of itraconazole(ITZ)/Soluplus~? solid dispersion. Solid dispersions prepared by hot melt extrusion (H...To investigate the effect of supersaturation induced by micelle formation during dissolution on the bioavailability of itraconazole(ITZ)/Soluplus~? solid dispersion. Solid dispersions prepared by hot melt extrusion (HME) were compressed into tablets directly with other excipients. Dissolution behavior of ITZ tablets was studied by dissolution testing and the morphology of micelles in dissolution media was studied using transmission electron microscopy (TEM). Drug transferring from stomach into intestine was simulated to obtain a supersaturated drug solution. Bioavailability studies were performed on the ITZ tablets and Sporanox~? in beagle dogs. The morphology of micelles in the dissolution media was observed to be spherical in shape, with an average size smaller than 100 nm. The supersaturated solutions formed by Soluplus~? micelles were stable and no precipitation took place over a period of 180 min. Compared with Sporanox~?, ITZ tablets exhibited a 2.50-fold increase in the AUC (0–96) of ITZ and a 1.95-fold increase in its active metabolite hydroxyitraconazole (OHITZ) in the plasma of beagle dogs. The results obtained provided clear evidence that not only the increase in the dissolution rate in the stomach, but also the supersaturation produced by micelles in the small intestine may be of great assistance in the successful development of poorly water-soluble drugs. The micelles formed by Soluplus~? enwrapped the molecular ITZ inside the core which promoted the amount of free drug in the intestinal cavity and carried ITZ through the aqueous boundary layer(ABL), resulting in high absorption by passive transportation across biological membranes. The uptake of intact micelles through pinocytosis together with the inhibition of P-glycoprotein-mediated drug efflux in intestinal epithelia contributed to the absorption of ITZ in the gastrointestinal tract. These results indicate that HME with Soluplus~?, which can induce supersaturation by micelleformation, may be of great assistance to the successful development of poorly watersoluble drugs.展开更多
Background There is an urgent need in clinical practice to measure the stress of parenting.The Caregiver Strain Questionnaire(CGSQ)was found to be useful to measure parenting stress,but it has not been validated among...Background There is an urgent need in clinical practice to measure the stress of parenting.The Caregiver Strain Questionnaire(CGSQ)was found to be useful to measure parenting stress,but it has not been validated among the Chinese population.Aims To assess the reliability and construct validity of the Chinese version of CGSQ among Chinese parents.Methods From 2016 to 2017,266 parents(patient group)with a child having DSM-5-defined attention deficit hyperactivity disorder(ADHD)(n=107)or autism spectrum disorder(ASD)(n=159)and 268 parents of healthy children(control group)were recruited to the present study in Kunming,Yunnan province.All the parents were asked to fill out the Chinese version of CGSQ.We conducted exploratory factor analysis and confirmatory factor analysis(CFA)to verify construct validity of CGSQ in both patient and control groups.Cronbach’s α coefficient as an index of internal consistency was assessed for each subscale.Fourteen days later,23 subjects filled out the scale again.Intra-class correlation coefficient was calculated to evaluate the test-retest reliability.Results(1)Cronbach’s alpha of the global scale was 0.901 for the control group and 0.952 for the patient group.The test-retest reliability for the whole scale was 0.890;(2)CFA indicated that the three-factor model had better fitting indices compared with the two-factor model in both groups.Besides,the fitting indices in the patient group were more favourable than those of the control group,withχ2/df=1.564,Goodness-of Fit Index=0.841,Comparative Fit Index=0.954,and root mean square error of approximation=0.065 for the patient group at three-factor model;(3)The caregiver strain of ASD parents was statistically higher than that of ADHD parents,and caregiver strain of ADHD parents was higher than that of control group.Conclusion These findings provide initial evidence to support the construct validity and reliability of CGSQ as a parenting stress measurement tool for Chinese parents,especially for parents of children with ADHD or ASD.展开更多
A rat model of spinal cord injury was established using the weight drop method. A cavity formed 14 days following spinal cord injury, and compact scar tissue formed by 56 days. Enzyme-linked immunosorbent assay and po...A rat model of spinal cord injury was established using the weight drop method. A cavity formed 14 days following spinal cord injury, and compact scar tissue formed by 56 days. Enzyme-linked immunosorbent assay and polymerase chain reaction enzyme-linked immunosorbent assay results demonstrated that glial fibrillary acidic protein and telomerase expression increased gradually after injury, peaked at 28 days, and then gradually decreased. Spearman rank correlation showed a positive correlation between glial fibrillary acidic protein expression and telomerase expression in the glial scar. These results suggest that telomerase promotes glial scar formation.展开更多
To find new antiviral agents,novel chalcone derivatives containing a purine moiety were designed and synthesized by combining bioactive substructures.The antiviral activities of the derivatives against tobacco mosaic ...To find new antiviral agents,novel chalcone derivatives containing a purine moiety were designed and synthesized by combining bioactive substructures.The antiviral activities of the derivatives against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) were evaluated.Results showed that most of the derivatives showed antiviral activities.Compounds 3n and 3p exhibited excellent curative,protective and inactivation activities against TMV,with the EC50values of 452.4,416.2,241.2 and 438.7,418.6,261.7 μg·mL-1,respectively,which were better than those of ribavirin (585.8,436.0 and 268.7 μg·mL-1).Compounds 3n and 3p showed remarkable curative and protective activities against CMV.Compound 3n showed a moderate affinity to TMV coat protein,with binding constant Ka and Kd values of 1.5 × 104 L·mol-1 and 79.8 μmol·L-1,respectively.These findings provided an important structural insight for further designs of highly active chalcone derivatives and a basis for further study on their mechanism of action.展开更多
Outgoing longwave radiation(OLR)at the top of the atmosphere(TOA)is a key parameter for understanding and interpreting the relationship between clouds,radiation,and climate interactions.It has been one of the operatio...Outgoing longwave radiation(OLR)at the top of the atmosphere(TOA)is a key parameter for understanding and interpreting the relationship between clouds,radiation,and climate interactions.It has been one of the operational products of the Fengyun(FY)meteorological satellites.OLR accuracy has gradually improved with advancements in satellite payload performance and the OLR retrieval algorithm.Supported by the National Key R&D Program Retrospective Calibration of Historical Chinese Earth Observation Satellite data(Richceos)project,a long-term OLR climate data record(CDR)was reprocessed based on the recalibrated Level 1 data of FY series satellites using the latest OLR retrieval algorithm.In this study,Fengyun-3B(FY-3B)’s reprocessed global OLR data from 2010 to 2018 were evaluated by using the Clouds and the Earth’s Radiant Energy System(CERES)global daily OLR data.The results showed that there was a high consistency between the FY-3B instantaneous OLR and CERES Single Scanner Footprint(SSF)OLR.Globally,between the two CDR datasets,the correlation coefficient reached 0.98,and the rootmean-square error(RMSE)was approximately 8-9 W m^(−2).The bias mainly came from the edge regions of the satellite orbit,which may be related to the satellite zenith angle and cloud cover distribution.It was shown that the longterm FY-3B OLR had temporal stability compared to CERES OLR long-term data.In terms of spatial distribution,the mean deviations showed zonal and seasonal characteristics,although seasonal fluctuations were observed in the differences between the two datasets.Effects of FY-3B OLR application to the South China Sea monsoon region and ENSO were demonstrated and analyzed,and the results showed that the seasonal deviation of FY-3B’s OLR comes mainly from the retrieval algorithm.However,it has little effect on the analysis of climate events.展开更多
基金funded by the National Nonprofit Institute Research Grant of Chinese Academy of Forestry(CAFYBB2011003,CAFYBB2011002)the Key Laboratory of Agrometeorological Support and Applied Technique of China Meteorological Administration(AMF201107,AMF201204)the National Natural Science Foundation of China(40801173)
文摘Remote sensing is a valuable and effective tool for monitoring and estimating aboveground biomass (AGB) in large areas.The current international research on biomass estimation by remote sensing technique mainly focused on forests,grasslands and crops,with relatively few applications for desert ecosystems.In this paper,Landsat Thematic Mapper (TM)/Enhanced Thematic Mapper Plus (ETM+) images from 1988 to 2007 and the data of 283 AGB samples in August 2007 were used to estimate the AGB for Mu Us Sandy Land over the past 30 years.Moreover,temporal and spatial distribution characteristics of AGB and influencing factors of climate and underlying surface were also studied.Results show that:(1) Differences of correlations exist in the fitted equations between AGB and different vegetation indices in desert areas.The modified soil adjusted vegetation index (MSAVI) and soil adjusted vegetation index (SAVI) show relatively higher correlations with AGB,while the correlation between normalized difference vegetation index (NDVI) and AGB is relatively lower.Error testing shows that the AGB-MSAVI model established can be used to accurately estimate AGB of Mu Us Sandy Land in August.(2) AGB in Mu Us Sandy Land shows the fluctuant characteristics over the past 30 years,which decreased from the 1980s to the 1990s,and increased from the 1990s to 2007.AGB in 2007 had the highest value,with a total AGB of 3.352×106 t.Moreover,in the 1990s,AGB had the lowest value with a total AGB of 2.328×106 t.(3) AGB with relatively higher values was mainly located in the middle and southern parts of Mu Us Sandy Land in the 1980s.AGB was low in the whole area in the1990s,and relatively higher AGB values were mainly located in the southern parts of Uxin.In 2007,AGB in the whole area was relatively higher than those of the last twenty years,and higher AGB values were mainly located in the northern,western and middle parts of Mu Us Sandy Land.
基金the National Natural Science Foundation of China(NSFC 81102399).
文摘To investigate the effect of supersaturation induced by micelle formation during dissolution on the bioavailability of itraconazole(ITZ)/Soluplus~? solid dispersion. Solid dispersions prepared by hot melt extrusion (HME) were compressed into tablets directly with other excipients. Dissolution behavior of ITZ tablets was studied by dissolution testing and the morphology of micelles in dissolution media was studied using transmission electron microscopy (TEM). Drug transferring from stomach into intestine was simulated to obtain a supersaturated drug solution. Bioavailability studies were performed on the ITZ tablets and Sporanox~? in beagle dogs. The morphology of micelles in the dissolution media was observed to be spherical in shape, with an average size smaller than 100 nm. The supersaturated solutions formed by Soluplus~? micelles were stable and no precipitation took place over a period of 180 min. Compared with Sporanox~?, ITZ tablets exhibited a 2.50-fold increase in the AUC (0–96) of ITZ and a 1.95-fold increase in its active metabolite hydroxyitraconazole (OHITZ) in the plasma of beagle dogs. The results obtained provided clear evidence that not only the increase in the dissolution rate in the stomach, but also the supersaturation produced by micelles in the small intestine may be of great assistance in the successful development of poorly water-soluble drugs. The micelles formed by Soluplus~? enwrapped the molecular ITZ inside the core which promoted the amount of free drug in the intestinal cavity and carried ITZ through the aqueous boundary layer(ABL), resulting in high absorption by passive transportation across biological membranes. The uptake of intact micelles through pinocytosis together with the inhibition of P-glycoprotein-mediated drug efflux in intestinal epithelia contributed to the absorption of ITZ in the gastrointestinal tract. These results indicate that HME with Soluplus~?, which can induce supersaturation by micelleformation, may be of great assistance to the successful development of poorly watersoluble drugs.
基金This work was supported by the National Natural Science Foundation of China(Grant No.81460218,30900488)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(Grant No.2015BAI13B01).
文摘Background There is an urgent need in clinical practice to measure the stress of parenting.The Caregiver Strain Questionnaire(CGSQ)was found to be useful to measure parenting stress,but it has not been validated among the Chinese population.Aims To assess the reliability and construct validity of the Chinese version of CGSQ among Chinese parents.Methods From 2016 to 2017,266 parents(patient group)with a child having DSM-5-defined attention deficit hyperactivity disorder(ADHD)(n=107)or autism spectrum disorder(ASD)(n=159)and 268 parents of healthy children(control group)were recruited to the present study in Kunming,Yunnan province.All the parents were asked to fill out the Chinese version of CGSQ.We conducted exploratory factor analysis and confirmatory factor analysis(CFA)to verify construct validity of CGSQ in both patient and control groups.Cronbach’s α coefficient as an index of internal consistency was assessed for each subscale.Fourteen days later,23 subjects filled out the scale again.Intra-class correlation coefficient was calculated to evaluate the test-retest reliability.Results(1)Cronbach’s alpha of the global scale was 0.901 for the control group and 0.952 for the patient group.The test-retest reliability for the whole scale was 0.890;(2)CFA indicated that the three-factor model had better fitting indices compared with the two-factor model in both groups.Besides,the fitting indices in the patient group were more favourable than those of the control group,withχ2/df=1.564,Goodness-of Fit Index=0.841,Comparative Fit Index=0.954,and root mean square error of approximation=0.065 for the patient group at three-factor model;(3)The caregiver strain of ASD parents was statistically higher than that of ADHD parents,and caregiver strain of ADHD parents was higher than that of control group.Conclusion These findings provide initial evidence to support the construct validity and reliability of CGSQ as a parenting stress measurement tool for Chinese parents,especially for parents of children with ADHD or ASD.
基金funded by the National Natural Science Foundation of China, No. 81060106
文摘A rat model of spinal cord injury was established using the weight drop method. A cavity formed 14 days following spinal cord injury, and compact scar tissue formed by 56 days. Enzyme-linked immunosorbent assay and polymerase chain reaction enzyme-linked immunosorbent assay results demonstrated that glial fibrillary acidic protein and telomerase expression increased gradually after injury, peaked at 28 days, and then gradually decreased. Spearman rank correlation showed a positive correlation between glial fibrillary acidic protein expression and telomerase expression in the glial scar. These results suggest that telomerase promotes glial scar formation.
文摘To find new antiviral agents,novel chalcone derivatives containing a purine moiety were designed and synthesized by combining bioactive substructures.The antiviral activities of the derivatives against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) were evaluated.Results showed that most of the derivatives showed antiviral activities.Compounds 3n and 3p exhibited excellent curative,protective and inactivation activities against TMV,with the EC50values of 452.4,416.2,241.2 and 438.7,418.6,261.7 μg·mL-1,respectively,which were better than those of ribavirin (585.8,436.0 and 268.7 μg·mL-1).Compounds 3n and 3p showed remarkable curative and protective activities against CMV.Compound 3n showed a moderate affinity to TMV coat protein,with binding constant Ka and Kd values of 1.5 × 104 L·mol-1 and 79.8 μmol·L-1,respectively.These findings provided an important structural insight for further designs of highly active chalcone derivatives and a basis for further study on their mechanism of action.
基金Supported by the National Key Research and Development Program of China(2018YFB0504900 and 2018YFB0504905)National Natural Science Foundation of China(41801278).
文摘Outgoing longwave radiation(OLR)at the top of the atmosphere(TOA)is a key parameter for understanding and interpreting the relationship between clouds,radiation,and climate interactions.It has been one of the operational products of the Fengyun(FY)meteorological satellites.OLR accuracy has gradually improved with advancements in satellite payload performance and the OLR retrieval algorithm.Supported by the National Key R&D Program Retrospective Calibration of Historical Chinese Earth Observation Satellite data(Richceos)project,a long-term OLR climate data record(CDR)was reprocessed based on the recalibrated Level 1 data of FY series satellites using the latest OLR retrieval algorithm.In this study,Fengyun-3B(FY-3B)’s reprocessed global OLR data from 2010 to 2018 were evaluated by using the Clouds and the Earth’s Radiant Energy System(CERES)global daily OLR data.The results showed that there was a high consistency between the FY-3B instantaneous OLR and CERES Single Scanner Footprint(SSF)OLR.Globally,between the two CDR datasets,the correlation coefficient reached 0.98,and the rootmean-square error(RMSE)was approximately 8-9 W m^(−2).The bias mainly came from the edge regions of the satellite orbit,which may be related to the satellite zenith angle and cloud cover distribution.It was shown that the longterm FY-3B OLR had temporal stability compared to CERES OLR long-term data.In terms of spatial distribution,the mean deviations showed zonal and seasonal characteristics,although seasonal fluctuations were observed in the differences between the two datasets.Effects of FY-3B OLR application to the South China Sea monsoon region and ENSO were demonstrated and analyzed,and the results showed that the seasonal deviation of FY-3B’s OLR comes mainly from the retrieval algorithm.However,it has little effect on the analysis of climate events.