The mining of limestone mines plays a crucial role in societal and economic advancement.However,mining activities have led to destructive variations in grassland ecology and soil,causing numerous environmental problem...The mining of limestone mines plays a crucial role in societal and economic advancement.However,mining activities have led to destructive variations in grassland ecology and soil,causing numerous environmental problems,and effective artificial restoration measures have been used to restore grasslands in the Shimenhe mining areas to different degrees.In this study,we investigated,examined and analyzed plant community structure and its correlation with soil properties across varying degrees of alpine grassland restoration in Qilian Mountains Shimenhe restoration mines using the sample method,and studied the changes in species diversity using five diversity indexes(Simpson index,Shannon index,Margalef index,Dominance index and Evenness index).This study showed that the plant community characteristics with high recovered degree(HRD)> middle recovered degree(MRD)> low recovered degree(LRD)> very low recovered degree(VLRD),11 plant genera comprising 11 species across 10 families were identified.Dominant families with robust ecological adaptability included Leguminosae,Rosaceae,Gramineae,Asteraceae,and Salicaceae.The highest Simpson,Shannon,Margalef and Evenness index of HRD grassland community species were 0.82,1.96,1.66 and 0.89,respectively.The highest Dominance index of VLRD grassland community species was 0.34,which required several restoration methods such as spraying and mulching.Soil pH and EC tended to decrease with increasing restoration,SOC,SMC,TP,AP,NH4-N,TN,AN and NO3-N tended to increase and the content of soil environmental factors contributed to vegetation growth across various restoration levels the mine grassland.In conclusion,our study indicated that the community structure gradually diversified and soil properties changed positively with the increase of restoration degrees in the Qilian Mountains Shimenhe mine,and the best results of HRD restoration were obtained.This study provides the theoretical basis for the restoration and conservation of grasslands in mining areas by demonstrating examined the correlation between plant characteristics and soil properties in restored grasslands in alpine mining areas.展开更多
Background: Small cell lung cancer (SCLC) is a highly aggressive disease characterized by early metastasis. Ane- uploid CD31- disseminated tumor cells (DTCs) and CD31+ disseminated tumor endothelial cells (DTECs) resi...Background: Small cell lung cancer (SCLC) is a highly aggressive disease characterized by early metastasis. Ane- uploid CD31- disseminated tumor cells (DTCs) and CD31+ disseminated tumor endothelial cells (DTECs) residing in the bone marrow are generally considered as the initiators of metastatic process. However, the clinical signifi- cance of DTCs and DTECs in SCLC remains poorly understood. The aim of this study is to investigate the clinical implications of diverse subtypes of highly heterogeneous DTCs and DTECs in SCLC patients. Methods: Subtraction enrichment and immunostaining-fluorescence in situ hybridization (SE-iFISH) was applied to enrich and perform comprehensive morphologic, karyotypic, and phenotypic characterization of aneuploid DTCs and DTECs in 30 patients. Additionally, co-detection of circulating tumor cells (CTCs) and circulating tumor endothelial cells (CTECs) was conducted on 24 of the enrolled patients. Proof-of-concept of the whole exon sequencings (WES) on precisely selected different subtypes of CTCs or DTCs, longitudinally detected from a representative case with pathologically confirmed bone marrow metastasis, was validated to feasibly reveal genetic mutations in these cells. Results: DTCs, DTECs and their subtypes were readily detectable in SCLC patients. Comparative analysis re- vealed that the number of DTCs and DTECs was significantly higher than that of their corresponding CTCs and CTECs ( P < 0.001 for both). Positive detection of disseminated tumor microemboli (DTM) or disseminated tumor endothelial microemboli (DTEM) was associated with inferior survival outcomes ( P = 0.046 and P = 0.048). Pa- tients with EpCAM+ DTCs detectable displayed significantly lower disease control rate (DCR) (16.67% vs 73.33%, P = 0.019), reduced median progression-free survival (mPFS) and median overall survival (mOS) compared with those with EpCAM- DTCs ( P = 0.028 and P = 0.002, respectively). WES analysis indicated that post-treatment DTCs isolated from bone marrow at the time of disease progression shared more homologous somatic gene mu- tations with pre-treatment CTCs compared with post-treatment CTCs. Conclusions: Our findings suggest that bone marrow sampling and characterization of DTC subtypes provided a valuable tool for predicting treatment response and the prognosis in SCLC. Moreover, DTCs inherit a greater amount of homologous somatic information from pre-treatment CTCs, indicating their potential role in disease progression and treatment resistance.展开更多
Related substances in pharmaceutical formulations are associated with their safety, efficacy and stability. However, there is no overall study already published on the assessment of related substances in the Compound ...Related substances in pharmaceutical formulations are associated with their safety, efficacy and stability. However, there is no overall study already published on the assessment of related substances in the Compound Ketoconazole and Clobetasol Propionate Cream. In this work, a reliable HPLC-TOF-MS qualitative method was developed for the analysis of related substances in this preparation with a quick and easy extraction procedure. Besides the active pharmaceutical ingredients, two compounds named ketoconazole impurity B′ optical isomer and ketoconazole impurity E were identified. Furthermore, a new HPLC method for qualitative and quantitative assessment on related substances and degradation products, which were found in the stability test, was established and validated. The single standard to determine multi-components method was applied in the quantitative analysis, which was an effective way for reducing cost and improving accuracy. This study can provide a creative idea for routine analysis of quality control of the Compound Ketoconazole and Clobetasol Propionate Cream.展开更多
Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via...Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via the carbonization of starch followed by sulfonation with concentrated sulfuric acid. N2 physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence and acid-base titration were used to characterize the obtained materials. The catalytic activity of sulfonated carbon was studied in the oxidation of aldehydes to carboxylic acids using 30 wt% H2O2 as oxidant. This oxidation protocol works well for various aldehydes including aromatic and aliphatic aldehydes. The sulfonated carbon can be recycled for three times without obvious loss of activity.展开更多
Ethanol induced method was applied to prepare Cu-Fe-Zr catalysts for conversion of syngas to higher alcohols. The catalytic performance of the catalysts induced by ethanol was superior to that of the catalyst prepared...Ethanol induced method was applied to prepare Cu-Fe-Zr catalysts for conversion of syngas to higher alcohols. The catalytic performance of the catalysts induced by ethanol was superior to that of the catalyst prepared by the conventional precipitation method. Among various procedures for ethanol induced method, it was found that incorporation of ethanol in the precipitation process was the better. After incorporation of ethanol, the crystal size of CuO decreased and the reduction of copper species became easier. The better activity of Cu-Fe-Zr catalysts prepared by ethanol induced procedures was probably caused by the higher dispersion of Cu species.展开更多
The roles of acidity and micropore structure of zeolite were studied in the hydrolysis of the model oligosaccharide of cellulose–cellobiose. HZSM-5, HY, HMOR and Hβ zeolites were selected as model catalysts for the ...The roles of acidity and micropore structure of zeolite were studied in the hydrolysis of the model oligosaccharide of cellulose–cellobiose. HZSM-5, HY, HMOR and Hβ zeolites were selected as model catalysts for the hydrolysis of cellobiose. The effect of acidity of zeolite, including the strength, type and location, on its catalytic activity was investigated. The strong Br?nsted acid sites located in micropores are the active sites for the hydrolysis of cellobiose to glucose. Meanwhile, the catalytic performance of zeolite is also dependent on the micropore size of zeolite.展开更多
In this paper,a reconstruction problem of the spatial dependent acoustic source from multiple frequency data is discussed.Suppose that the source function is supported on a bounded domain and the piecewise constant in...In this paper,a reconstruction problem of the spatial dependent acoustic source from multiple frequency data is discussed.Suppose that the source function is supported on a bounded domain and the piecewise constant intensities of the source are known on the support.We characterize unknown domain by the level set technique.And the level set function can be modeled by a Hamilton-Jacobi system.We use the ensemble Kalman filter approach to analyze the system state.This method can avoid to deal with the nonlinearity directly and reduce the computation complexity.In addition,the algorithm can achieve the stable state quickly with the Hamilton-Jacobi system.From some numerical examples,we show these advantages and verify the feasibility and effectiveness.展开更多
In recent years,subsynchronous resonance(SSR)has frequently occurred in DFIG-connected series-compensated systems.For the analysis and prevention,it is of great importance to achieve wide area monitoring of the incide...In recent years,subsynchronous resonance(SSR)has frequently occurred in DFIG-connected series-compensated systems.For the analysis and prevention,it is of great importance to achieve wide area monitoring of the incident.This paper presents a Hankel dynamic mode decomposition(DMD)method to identify SSR parameters using synchrophasor data.The basic idea is to employ the DMD technique to explore the subspace of Hankel matrices constructed by synchrophasors.It is analytically demonstrated that the subspace of these Hankel matrices is a combination of fundamental and SSR modes.Therefore,the SSR parameters can be calculated once the modal parameter is extracted.Compared with the existing method,the presented work has better dynamic performances as it requires much less data.Thus,it is more suitable for practical cases in which the SSR characteristics are timevarying.The effectiveness and superiority of the proposed method have been verified by both simulations and field data.展开更多
Fine blanking parts with sharp corners produce collapse angles in the fine blanking process,and larger collapse angles can affect the parts’ performance and lifetime. In this paper,a fine blanking part with sharp cor...Fine blanking parts with sharp corners produce collapse angles in the fine blanking process,and larger collapse angles can affect the parts’ performance and lifetime. In this paper,a fine blanking part with sharp corners was taken as an example to analyze the forming mechanism of the collapse angles by DEFORM 3 D,then studying the influence of the position of the V-ring indenter of die on the collapse angle. It was concluded that the material’s metal flow line was intensive near the blanking clearance;The equivalent stress area of the material was mainly concentrated around the blanking clearance,and then gradually shrinked to joint of part and scrap;the closer the distance L was,and the smaller equivalent stress area was mainly concentrated around the blanking clearance was,and the smaller collapse angle was.展开更多
Herein, we describe a strategy for fabricating ordered mesoporous In2O3-reduced graphene oxide(r GO)nanocomposite through ultrasonic mixing, where ordered mesoporous In2O3 nanoparticles are synthesized via the nanocas...Herein, we describe a strategy for fabricating ordered mesoporous In2O3-reduced graphene oxide(r GO)nanocomposite through ultrasonic mixing, where ordered mesoporous In2O3 nanoparticles are synthesized via the nanocasting route by using mesoporous silica as a hard template, which possess ordered mesostructure with a large surface area of 81 m2g-1, and r GO nanosheets are synthesized from graphite via graphene oxide(GO) as intermediate. After coupled with r GO, mesoporous In2O3 could maintain its ordered mesostructure. We subsequently investigate the gas-sensing properties of all the In2O3 specimens with or without r GO for different gases. The results exhibit the ordered mesoporous In2O3-r GO nanocomposite possesses significantly enhanced response to ethanol even at low concentration levels, superior over pure mesoporous In2O3 nanoparticles. Similar strategy could be extended to other ordered mesoporous metal oxide–r GO nanocomposite for improving the gas-sensing property.展开更多
Most crops in northern China are irrigated,but the topography affects the water use,soil erosion,runoff and yields.Technologies for collecting high-resolution topographic data are essential for adequately assessing th...Most crops in northern China are irrigated,but the topography affects the water use,soil erosion,runoff and yields.Technologies for collecting high-resolution topographic data are essential for adequately assessing these effects.Ground surveys and techniques of light detection and ranging have good accuracy,but data acquisition can be time-consuming and expensive for large catchments.Recent rapid technological development has provided new,flexible,high-resolution methods for collecting topographic data,such as photogrammetry using unmanned aerial vehicles(UAVs).The accuracy of UAV photogrammetry for generating high-resolution Digital Elevation Model(DEM)and for determining the width of irrigation channels,however,has not been assessed.A fixed-wing UAV was used for collecting high-resolution(0.15 m)topographic data for the Hetao irrigation district,the third largest irrigation district in China.112 ground checkpoints(GCPs)were surveyed by using a real-time kinematic global positioning system to evaluate the accuracy of the DEMs and channel widths.A comparison of manually measured channel widths with the widths derived from the DEMs indicated that the DEM-derived widths had vertical and horizontal root mean square errors of 13.0 and 7.9 cm,respectively.UAV photogrammetric data can thus be used for land surveying,digital mapping,calculating channel capacity,monitoring crops,and predicting yields,with the advantages of economy,speed and ease.展开更多
Due to the weak information about cultural targets in the complex marine environment,an omission problem exists in large-scale mariculture extraction using single-view and single-source images.To overcome this problem...Due to the weak information about cultural targets in the complex marine environment,an omission problem exists in large-scale mariculture extraction using single-view and single-source images.To overcome this problem,we developed a mariculture extraction method that combines dense time-series Sentinel-2 and Sentinel-1 data.A high-precision Chinese mariculture distribution map for 2020 was produced with an overall accuracy of 94.00%and a kappa coefficient of 0.91.The results show that(1)the total area of mariculture was 1173249.22 ha on the national scale,which was significantly larger than the previous studies(459595.70 and 205920.28 ha,respectively),with Shandong Province(39.09%)having the largest proportion;(2)China’s mariculture presented a spatial distribution characteristic of‘Denser North and Sparser South’,and mariculture was centralized in the coastal zones of the northern provinces(60.76%)rather than the southern provinces;(3)the official production statistics and remote sensing-derived mariculture area revealed a highly corresponding trend at the provincial level,with an R2 reaching 0.78,which is much higher than the 0.07 and 0.41 values of the comparison data.The results directly provide data reference for mariculture production estimation and site selection or ideas for mariculture extraction in other regions and globally.展开更多
Chimeric antigen receptor-based T-cell immunotherapy is a promising strategy for treatment of hematological malignant tumors;however,its efficacy towards solid cancer remains challenging.We therefore focused on develo...Chimeric antigen receptor-based T-cell immunotherapy is a promising strategy for treatment of hematological malignant tumors;however,its efficacy towards solid cancer remains challenging.We therefore focused on developing nanobody-based CAR-T cells that treat the solid tumor.CD105 expression is upregulated on neoangiogenic endothelial and cancer cells.CD105 has been developed as a drug target.Here we show the generation of a CD105-specific nanobody,an anti-human CD105 CAR-T cells,by inserting the sequences for anti-CD105 nanobody-linked standard cassette genes into AAVS1 site using CRISPR/Cas9 technology.Co-culture with CD105+target cells led to the activation of anti-CD105 CAR-T cells that displayed the typically activated cytotoxic T-cell characters,ability to proliferate,the production of pro-inflammatory cytokines,and the specific killing efficacy against CD105+target cells in vitro.The in vivo treatment with anti-CD105 CAR-T cells significantly inhibited the growth of implanted CD105+tumors,reduced tumor weight,and prolonged the survival time of tumor-bearing NOD/SCID mice.Nanobody-based CAR-T cells can therefore function as an antitumor agent in human tumor xenograft models.Our findings determined that the strategy of nanobody-based CAR-T cells engineered by CRISPR/Cas9 system has a certain potential to treat solid tumor through targeting CD105 antigen.展开更多
In recent years,subsynchronous control interaction(SSCI)has frequently taken place in renewable-connected power systems.To counter this issue,utilities have been seeking tools for fast and accurate identification of S...In recent years,subsynchronous control interaction(SSCI)has frequently taken place in renewable-connected power systems.To counter this issue,utilities have been seeking tools for fast and accurate identification of SSCI events.The main challenges of SSCI monitoring are the time-varying nature and uncertain modes of SSCI events.Accordingly,this paper presents a simple but effective method that takes advantage of intrinsic time-scale decomposition(ITD).The main purpose is to improve the accuracy and robustness of ITD by incorporating the least-squares method.Results show that the proposed method strikes a good balance between dynamic performance and estimation accuracy.More importantly,the method does not require any prior information,and its performance is therefore not affected by the frequency constitution of the SSCI.Comprehensive comparative studies are conducted to demonstrate the usefulness of the method through synthetic signals,electromagnetic temporary program(EMTP)simulations,and field-recorded SSCI data.Finally,real-time simulation tests are conducted to show the feasibility of the method for real-time monitoring.展开更多
Mesoporous anatase TiO2 spheres with high surface area(119 m^2g^(-1)) were successfully synthesized via a facile and green template-free method. The prepared TiO2 was characterized by X-ray diffraction(XRD),N2 a...Mesoporous anatase TiO2 spheres with high surface area(119 m^2g^(-1)) were successfully synthesized via a facile and green template-free method. The prepared TiO2 was characterized by X-ray diffraction(XRD),N2 adsorption, scanning electron microscopy(SEM), transmission electron microscopy(TEM) and UV–vis absorbance spectra. It was found that the prepared TiO2 is characterized by pure anatase phase, which shows uniform spheres and has a typical mesostructure with a high specific surface area and a large pore volume. The effects of complexant(acetylacetone) amount, crystallization temperature and calcination temperature were also investigated. Based on the results, a sketch for the preparation of mesoporous TiO2 was proposed. First, complex formed between tetrabutyl titanate and acetylacetone in ethanol. After introduction of aqueous of ammonia sulfate and urea, hydrolysis of tetrabutyl titanate would occur slowly,and sol of TiO2 was formed. Then, crystallization proceeded under hydrothermal conditions. Calcination process favored the formation of bigger TiO2 crystal through combining of the small crystals in TiO2.This led to the formation of bigger mesopores between TiO2 crystals. Photocatalytic activity of the prepared TiO2 was evaluated by decomposition of methyl orange.展开更多
Sense mutations in several conserved modifiable sites of histone H3 have been found to be strongly correlated with multiple tissuespecific clinical cancers.These clinical site mutants acquire a distinctively new epige...Sense mutations in several conserved modifiable sites of histone H3 have been found to be strongly correlated with multiple tissuespecific clinical cancers.These clinical site mutants acquire a distinctively new epigenetic role and mediate cancer evolution.In this study,we mimicked histone H3 at the 56th lysine(H3K56)mutant incorporation in mouse embryonic stem cells(mESCs)by lentivirus-mediated ectopic expression and analyzed the effects on replication and epigenetic regulation.The data show that two types of H3K56 mutants,namely H3 lysine 56-to-methionine(H3K56M)and H3 lysine 56-to-alanine(H3K56A),promote replication by recruiting more minichromosome maintenance complex component 3 and checkpoint kinase 1 onto chromatin compared with wild-type histone H3 and other site substitution mutants.Under this condition,the frequency of genomic copy number gain in H3K56M and H3K56A cells globally increases,especially in the Mycl1 region,a known molecular marker frequently occurring in multiple malignant cancers.Additionally,we found the disruption of H3K56 acetylation distribution in the copy-gain regions,which indicates a probable epigenetic mechanism of H3K56M and H3K56A.We then identified that H3K56M and H3K56A can trigger a potential adaptation to transcription;genes involved in the mitogen-activated protein kinase pathway are partially upregulated,whereas genes associated with intrinsic apoptotic function show obvious downregulation.The final outcome of ectopic H3K56M and H3K56A incorporation in mESCs is an enhanced ability to form carcinomas.This work indicates that H3K56 site conservation and proper modification play important roles in harmonizing the function of the replication machinery in mESCs.展开更多
基金supported by the National Key R&D Program of China (Nos. 2022YFF1303301, 2022YFF1302603)the National Natural Science Foundation of China (Nos. 52179026, 42001035, 42101115)+5 种基金the Science and Technology Program of Gansu Province (Nos. 22JR5RA072, 22JR5RA068)the Postdoctoral Funding Program of Gansu Province (No. E339880139)the Natural Science Foundation of Gansu Province (No. E331040901)the Science and Technology Fund of Gansu Province (No. 23JRRA640)the Consulting and Research Project of the Gansu Research Institute of Chinese Engineering Science and Technology Development Strategy (No. GS2022ZDI03)the Open Fund of Technology Innovation Center for Mine Geological Environment Restoration in the Alpine and Arid Regions (No. HHGCKK2204)
文摘The mining of limestone mines plays a crucial role in societal and economic advancement.However,mining activities have led to destructive variations in grassland ecology and soil,causing numerous environmental problems,and effective artificial restoration measures have been used to restore grasslands in the Shimenhe mining areas to different degrees.In this study,we investigated,examined and analyzed plant community structure and its correlation with soil properties across varying degrees of alpine grassland restoration in Qilian Mountains Shimenhe restoration mines using the sample method,and studied the changes in species diversity using five diversity indexes(Simpson index,Shannon index,Margalef index,Dominance index and Evenness index).This study showed that the plant community characteristics with high recovered degree(HRD)> middle recovered degree(MRD)> low recovered degree(LRD)> very low recovered degree(VLRD),11 plant genera comprising 11 species across 10 families were identified.Dominant families with robust ecological adaptability included Leguminosae,Rosaceae,Gramineae,Asteraceae,and Salicaceae.The highest Simpson,Shannon,Margalef and Evenness index of HRD grassland community species were 0.82,1.96,1.66 and 0.89,respectively.The highest Dominance index of VLRD grassland community species was 0.34,which required several restoration methods such as spraying and mulching.Soil pH and EC tended to decrease with increasing restoration,SOC,SMC,TP,AP,NH4-N,TN,AN and NO3-N tended to increase and the content of soil environmental factors contributed to vegetation growth across various restoration levels the mine grassland.In conclusion,our study indicated that the community structure gradually diversified and soil properties changed positively with the increase of restoration degrees in the Qilian Mountains Shimenhe mine,and the best results of HRD restoration were obtained.This study provides the theoretical basis for the restoration and conservation of grasslands in mining areas by demonstrating examined the correlation between plant characteristics and soil properties in restored grasslands in alpine mining areas.
基金Beijing Municipal Science and Technol-ogy Commission(grant number Z211100002921013)Tongzhou Liang-gao Talents Project(grant number YH201920)+2 种基金Beijing Municipal Public Welfare Development and Reform Pilot Project for Medical Research In-stitutes(grant number JYY2024-14)Beijing Municipal Public Wel-fare Development and Reform Pilot Project for Medical Research Insti-tutes(grant number JYY2023-15)We thank all participants and their families for supporting this study.
文摘Background: Small cell lung cancer (SCLC) is a highly aggressive disease characterized by early metastasis. Ane- uploid CD31- disseminated tumor cells (DTCs) and CD31+ disseminated tumor endothelial cells (DTECs) residing in the bone marrow are generally considered as the initiators of metastatic process. However, the clinical signifi- cance of DTCs and DTECs in SCLC remains poorly understood. The aim of this study is to investigate the clinical implications of diverse subtypes of highly heterogeneous DTCs and DTECs in SCLC patients. Methods: Subtraction enrichment and immunostaining-fluorescence in situ hybridization (SE-iFISH) was applied to enrich and perform comprehensive morphologic, karyotypic, and phenotypic characterization of aneuploid DTCs and DTECs in 30 patients. Additionally, co-detection of circulating tumor cells (CTCs) and circulating tumor endothelial cells (CTECs) was conducted on 24 of the enrolled patients. Proof-of-concept of the whole exon sequencings (WES) on precisely selected different subtypes of CTCs or DTCs, longitudinally detected from a representative case with pathologically confirmed bone marrow metastasis, was validated to feasibly reveal genetic mutations in these cells. Results: DTCs, DTECs and their subtypes were readily detectable in SCLC patients. Comparative analysis re- vealed that the number of DTCs and DTECs was significantly higher than that of their corresponding CTCs and CTECs ( P < 0.001 for both). Positive detection of disseminated tumor microemboli (DTM) or disseminated tumor endothelial microemboli (DTEM) was associated with inferior survival outcomes ( P = 0.046 and P = 0.048). Pa- tients with EpCAM+ DTCs detectable displayed significantly lower disease control rate (DCR) (16.67% vs 73.33%, P = 0.019), reduced median progression-free survival (mPFS) and median overall survival (mOS) compared with those with EpCAM- DTCs ( P = 0.028 and P = 0.002, respectively). WES analysis indicated that post-treatment DTCs isolated from bone marrow at the time of disease progression shared more homologous somatic gene mu- tations with pre-treatment CTCs compared with post-treatment CTCs. Conclusions: Our findings suggest that bone marrow sampling and characterization of DTC subtypes provided a valuable tool for predicting treatment response and the prognosis in SCLC. Moreover, DTCs inherit a greater amount of homologous somatic information from pre-treatment CTCs, indicating their potential role in disease progression and treatment resistance.
文摘Related substances in pharmaceutical formulations are associated with their safety, efficacy and stability. However, there is no overall study already published on the assessment of related substances in the Compound Ketoconazole and Clobetasol Propionate Cream. In this work, a reliable HPLC-TOF-MS qualitative method was developed for the analysis of related substances in this preparation with a quick and easy extraction procedure. Besides the active pharmaceutical ingredients, two compounds named ketoconazole impurity B′ optical isomer and ketoconazole impurity E were identified. Furthermore, a new HPLC method for qualitative and quantitative assessment on related substances and degradation products, which were found in the stability test, was established and validated. The single standard to determine multi-components method was applied in the quantitative analysis, which was an effective way for reducing cost and improving accuracy. This study can provide a creative idea for routine analysis of quality control of the Compound Ketoconazole and Clobetasol Propionate Cream.
基金supported by the National Nature Science Foundation of China (J1210060, 21143002)
文摘Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via the carbonization of starch followed by sulfonation with concentrated sulfuric acid. N2 physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence and acid-base titration were used to characterize the obtained materials. The catalytic activity of sulfonated carbon was studied in the oxidation of aldehydes to carboxylic acids using 30 wt% H2O2 as oxidant. This oxidation protocol works well for various aldehydes including aromatic and aliphatic aldehydes. The sulfonated carbon can be recycled for three times without obvious loss of activity.
基金Natural Science Foundation of State Key Laboratory of Coal Conversion(No09-610)
文摘Ethanol induced method was applied to prepare Cu-Fe-Zr catalysts for conversion of syngas to higher alcohols. The catalytic performance of the catalysts induced by ethanol was superior to that of the catalyst prepared by the conventional precipitation method. Among various procedures for ethanol induced method, it was found that incorporation of ethanol in the precipitation process was the better. After incorporation of ethanol, the crystal size of CuO decreased and the reduction of copper species became easier. The better activity of Cu-Fe-Zr catalysts prepared by ethanol induced procedures was probably caused by the higher dispersion of Cu species.
基金supported by the National Natural Science Foundation of China(Grant:U1304209,J1210060)the Undergraduate Innovation Education Project of Zhengzhou University for the financial support(Grant:2014sjxm008)
文摘The roles of acidity and micropore structure of zeolite were studied in the hydrolysis of the model oligosaccharide of cellulose–cellobiose. HZSM-5, HY, HMOR and Hβ zeolites were selected as model catalysts for the hydrolysis of cellobiose. The effect of acidity of zeolite, including the strength, type and location, on its catalytic activity was investigated. The strong Br?nsted acid sites located in micropores are the active sites for the hydrolysis of cellobiose to glucose. Meanwhile, the catalytic performance of zeolite is also dependent on the micropore size of zeolite.
文摘In this paper,a reconstruction problem of the spatial dependent acoustic source from multiple frequency data is discussed.Suppose that the source function is supported on a bounded domain and the piecewise constant intensities of the source are known on the support.We characterize unknown domain by the level set technique.And the level set function can be modeled by a Hamilton-Jacobi system.We use the ensemble Kalman filter approach to analyze the system state.This method can avoid to deal with the nonlinearity directly and reduce the computation complexity.In addition,the algorithm can achieve the stable state quickly with the Hamilton-Jacobi system.From some numerical examples,we show these advantages and verify the feasibility and effectiveness.
基金supported by the China Key Technology Research on Risk Perception of Sub-Synchronous Oscillation of Grid with Large-Scale New Energy Access SGTYHT/21-JS-223.
文摘In recent years,subsynchronous resonance(SSR)has frequently occurred in DFIG-connected series-compensated systems.For the analysis and prevention,it is of great importance to achieve wide area monitoring of the incident.This paper presents a Hankel dynamic mode decomposition(DMD)method to identify SSR parameters using synchrophasor data.The basic idea is to employ the DMD technique to explore the subspace of Hankel matrices constructed by synchrophasors.It is analytically demonstrated that the subspace of these Hankel matrices is a combination of fundamental and SSR modes.Therefore,the SSR parameters can be calculated once the modal parameter is extracted.Compared with the existing method,the presented work has better dynamic performances as it requires much less data.Thus,it is more suitable for practical cases in which the SSR characteristics are timevarying.The effectiveness and superiority of the proposed method have been verified by both simulations and field data.
文摘Fine blanking parts with sharp corners produce collapse angles in the fine blanking process,and larger collapse angles can affect the parts’ performance and lifetime. In this paper,a fine blanking part with sharp corners was taken as an example to analyze the forming mechanism of the collapse angles by DEFORM 3 D,then studying the influence of the position of the V-ring indenter of die on the collapse angle. It was concluded that the material’s metal flow line was intensive near the blanking clearance;The equivalent stress area of the material was mainly concentrated around the blanking clearance,and then gradually shrinked to joint of part and scrap;the closer the distance L was,and the smaller equivalent stress area was mainly concentrated around the blanking clearance was,and the smaller collapse angle was.
基金supported by the National Natural Science Foundation of China(21006116,51362024)the Natural Science Foundation of Ningxia(NZ12111,NZ14010)the Prophase Research Special Project of the National Basic Research Program of China(2012CB723106)
文摘Herein, we describe a strategy for fabricating ordered mesoporous In2O3-reduced graphene oxide(r GO)nanocomposite through ultrasonic mixing, where ordered mesoporous In2O3 nanoparticles are synthesized via the nanocasting route by using mesoporous silica as a hard template, which possess ordered mesostructure with a large surface area of 81 m2g-1, and r GO nanosheets are synthesized from graphite via graphene oxide(GO) as intermediate. After coupled with r GO, mesoporous In2O3 could maintain its ordered mesostructure. We subsequently investigate the gas-sensing properties of all the In2O3 specimens with or without r GO for different gases. The results exhibit the ordered mesoporous In2O3-r GO nanocomposite possesses significantly enhanced response to ethanol even at low concentration levels, superior over pure mesoporous In2O3 nanoparticles. Similar strategy could be extended to other ordered mesoporous metal oxide–r GO nanocomposite for improving the gas-sensing property.
基金This work was financially supported by Major Project of National Key R&D Plan from the MOST of China(2017YFC0403203)National Natural Science Foundation of China(41771315,41301283,61402374,41371274,41301507)+2 种基金Natural Science Foundation of Shaanxi Province(2015JM4142)EU Horizon 2020 research and innovation programme(ISQAPER:635750)State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau(A314021402-1702).
文摘Most crops in northern China are irrigated,but the topography affects the water use,soil erosion,runoff and yields.Technologies for collecting high-resolution topographic data are essential for adequately assessing these effects.Ground surveys and techniques of light detection and ranging have good accuracy,but data acquisition can be time-consuming and expensive for large catchments.Recent rapid technological development has provided new,flexible,high-resolution methods for collecting topographic data,such as photogrammetry using unmanned aerial vehicles(UAVs).The accuracy of UAV photogrammetry for generating high-resolution Digital Elevation Model(DEM)and for determining the width of irrigation channels,however,has not been assessed.A fixed-wing UAV was used for collecting high-resolution(0.15 m)topographic data for the Hetao irrigation district,the third largest irrigation district in China.112 ground checkpoints(GCPs)were surveyed by using a real-time kinematic global positioning system to evaluate the accuracy of the DEMs and channel widths.A comparison of manually measured channel widths with the widths derived from the DEMs indicated that the DEM-derived widths had vertical and horizontal root mean square errors of 13.0 and 7.9 cm,respectively.UAV photogrammetric data can thus be used for land surveying,digital mapping,calculating channel capacity,monitoring crops,and predicting yields,with the advantages of economy,speed and ease.
基金supported by the National Key Research and Development Program of China[grant number 2021YFB3900501]the National Natural Science Foundation of China[grant number 41671436,41901354,41890854]the Innovation Project of LREIS[grant number O88RAA01YA].
文摘Due to the weak information about cultural targets in the complex marine environment,an omission problem exists in large-scale mariculture extraction using single-view and single-source images.To overcome this problem,we developed a mariculture extraction method that combines dense time-series Sentinel-2 and Sentinel-1 data.A high-precision Chinese mariculture distribution map for 2020 was produced with an overall accuracy of 94.00%and a kappa coefficient of 0.91.The results show that(1)the total area of mariculture was 1173249.22 ha on the national scale,which was significantly larger than the previous studies(459595.70 and 205920.28 ha,respectively),with Shandong Province(39.09%)having the largest proportion;(2)China’s mariculture presented a spatial distribution characteristic of‘Denser North and Sparser South’,and mariculture was centralized in the coastal zones of the northern provinces(60.76%)rather than the southern provinces;(3)the official production statistics and remote sensing-derived mariculture area revealed a highly corresponding trend at the provincial level,with an R2 reaching 0.78,which is much higher than the 0.07 and 0.41 values of the comparison data.The results directly provide data reference for mariculture production estimation and site selection or ideas for mariculture extraction in other regions and globally.
基金supported,in part,by grants from Project of National Natural Scientific Foundation of China(number 81773254)Programs for Changjiang Scholars and Innovative Research Team in University(number IRT_15R13)+6 种基金International Cooperation Project of the Misnistry of Science and Technology of China(number 2015 DP A31320)Project for Innovative Research Team in Guangxi Natural Science Foundation(2015G XNSFFA139001)Project for International Nanobody Research Center of Guangxi(number GuiKe-AD17195001)Partial support was provided by the NIH-NIEHS(RIVER Award)R35 ES030443-01the NIEHS Superfund Research Program P42 ES004699,Guangxi First-class Discipline Project for Pharmaceutical Sciences(number GXFCDP-PS-2018)National Key Research and Development Plan"Intergovernmental Cooperation in International Scientific and Technological Innovation"(number 2019YFE0117300)Guangxi Science and Technology Base and Talents Project(number GuiKe-AD20238062).
文摘Chimeric antigen receptor-based T-cell immunotherapy is a promising strategy for treatment of hematological malignant tumors;however,its efficacy towards solid cancer remains challenging.We therefore focused on developing nanobody-based CAR-T cells that treat the solid tumor.CD105 expression is upregulated on neoangiogenic endothelial and cancer cells.CD105 has been developed as a drug target.Here we show the generation of a CD105-specific nanobody,an anti-human CD105 CAR-T cells,by inserting the sequences for anti-CD105 nanobody-linked standard cassette genes into AAVS1 site using CRISPR/Cas9 technology.Co-culture with CD105+target cells led to the activation of anti-CD105 CAR-T cells that displayed the typically activated cytotoxic T-cell characters,ability to proliferate,the production of pro-inflammatory cytokines,and the specific killing efficacy against CD105+target cells in vitro.The in vivo treatment with anti-CD105 CAR-T cells significantly inhibited the growth of implanted CD105+tumors,reduced tumor weight,and prolonged the survival time of tumor-bearing NOD/SCID mice.Nanobody-based CAR-T cells can therefore function as an antitumor agent in human tumor xenograft models.Our findings determined that the strategy of nanobody-based CAR-T cells engineered by CRISPR/Cas9 system has a certain potential to treat solid tumor through targeting CD105 antigen.
基金supported in part by the National Natural Science Foundation of China(No.51907133)in part by the Fundamental Research Funds for the Central Universities(No.YJ201911).
文摘In recent years,subsynchronous control interaction(SSCI)has frequently taken place in renewable-connected power systems.To counter this issue,utilities have been seeking tools for fast and accurate identification of SSCI events.The main challenges of SSCI monitoring are the time-varying nature and uncertain modes of SSCI events.Accordingly,this paper presents a simple but effective method that takes advantage of intrinsic time-scale decomposition(ITD).The main purpose is to improve the accuracy and robustness of ITD by incorporating the least-squares method.Results show that the proposed method strikes a good balance between dynamic performance and estimation accuracy.More importantly,the method does not require any prior information,and its performance is therefore not affected by the frequency constitution of the SSCI.Comprehensive comparative studies are conducted to demonstrate the usefulness of the method through synthetic signals,electromagnetic temporary program(EMTP)simulations,and field-recorded SSCI data.Finally,real-time simulation tests are conducted to show the feasibility of the method for real-time monitoring.
基金supported by the National Natural Science Foundation of China (Nos. 21206150, U1304209 and U1204215)the Foundation for University Young Key Teacher by Henan Province (No. 2014GGJS-005)
文摘Mesoporous anatase TiO2 spheres with high surface area(119 m^2g^(-1)) were successfully synthesized via a facile and green template-free method. The prepared TiO2 was characterized by X-ray diffraction(XRD),N2 adsorption, scanning electron microscopy(SEM), transmission electron microscopy(TEM) and UV–vis absorbance spectra. It was found that the prepared TiO2 is characterized by pure anatase phase, which shows uniform spheres and has a typical mesostructure with a high specific surface area and a large pore volume. The effects of complexant(acetylacetone) amount, crystallization temperature and calcination temperature were also investigated. Based on the results, a sketch for the preparation of mesoporous TiO2 was proposed. First, complex formed between tetrabutyl titanate and acetylacetone in ethanol. After introduction of aqueous of ammonia sulfate and urea, hydrolysis of tetrabutyl titanate would occur slowly,and sol of TiO2 was formed. Then, crystallization proceeded under hydrothermal conditions. Calcination process favored the formation of bigger TiO2 crystal through combining of the small crystals in TiO2.This led to the formation of bigger mesopores between TiO2 crystals. Photocatalytic activity of the prepared TiO2 was evaluated by decomposition of methyl orange.
基金supported by grants from the National Key Research and Development Program of China(2017YFA0103301)the National Natural Science Foundation of China(81972743)China Postdoctoral Science Foundation(2020M671205).
文摘Sense mutations in several conserved modifiable sites of histone H3 have been found to be strongly correlated with multiple tissuespecific clinical cancers.These clinical site mutants acquire a distinctively new epigenetic role and mediate cancer evolution.In this study,we mimicked histone H3 at the 56th lysine(H3K56)mutant incorporation in mouse embryonic stem cells(mESCs)by lentivirus-mediated ectopic expression and analyzed the effects on replication and epigenetic regulation.The data show that two types of H3K56 mutants,namely H3 lysine 56-to-methionine(H3K56M)and H3 lysine 56-to-alanine(H3K56A),promote replication by recruiting more minichromosome maintenance complex component 3 and checkpoint kinase 1 onto chromatin compared with wild-type histone H3 and other site substitution mutants.Under this condition,the frequency of genomic copy number gain in H3K56M and H3K56A cells globally increases,especially in the Mycl1 region,a known molecular marker frequently occurring in multiple malignant cancers.Additionally,we found the disruption of H3K56 acetylation distribution in the copy-gain regions,which indicates a probable epigenetic mechanism of H3K56M and H3K56A.We then identified that H3K56M and H3K56A can trigger a potential adaptation to transcription;genes involved in the mitogen-activated protein kinase pathway are partially upregulated,whereas genes associated with intrinsic apoptotic function show obvious downregulation.The final outcome of ectopic H3K56M and H3K56A incorporation in mESCs is an enhanced ability to form carcinomas.This work indicates that H3K56 site conservation and proper modification play important roles in harmonizing the function of the replication machinery in mESCs.