In the era of serious greenhouse gas emission and energy shortage,it is necessary to use solid waste to prepare new renewable materials.In this work,the potential application of reed straw and electric furnace dust wa...In the era of serious greenhouse gas emission and energy shortage,it is necessary to use solid waste to prepare new renewable materials.In this work,the potential application of reed straw and electric furnace dust was explored.Firstly,magnetic carbon carrier(EFD&C)was prepared by high temperature calcination,and then magnetic carbon catalyst(SM@EFD&C)was prepared by activation of sodium methoxide.The catalyst was used to prepare biodiesel by transesterification reaction to test its activity and stability.Reed biochar,EFD&C and SM@EFD&C were detected by Diffraction of X-rays(XRD),Fourier transform infrared(FT-IR),Inductively coupled plasma(ICP),Scanning electron microscope(SEM),Transmission electron microscope(TEM),Brunauer-Emmett-Teller(BET),Vibrating sample magnetometer(VSM),Temperature programmed desorption of CO_(2)(CO_(2)-TPD)and Thermogravimetric analysis(TG-DTG).The results showed that SM@EFD&C catalyst had some characteristics including porous structure,easy adsorption and better magnetism.Under the reaction conditions of 65℃for 2 h with 6 wt%catalyst and methanol/oil molar ratio of 15:1,the biodiesel yields from reed biochar and EFD&C were only 4.88 wt%and 0.03 wt%,respectively,while the yield from SM@EFD&C catalyst reached 93.14 wt%(89.84 wt%after 7 cycles)under the same conditions,which proved that it had good catalytic activity and stability when used in biodiesel production.This study is of great significance of carbon dioxide emission reduction and environmental protection.展开更多
[Objectives]To investigate the effect of low temperature treatment on cotton leaves at the two-leaf stage.[Methods]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They w...[Objectives]To investigate the effect of low temperature treatment on cotton leaves at the two-leaf stage.[Methods]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Results]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Conclusions]These genes may play an important role in improving the cold resistance of cotton.展开更多
In this paper, we suggest one compound chaos image encryption method with time- varying multilevel initial parameters. This algorithm combines Subsection-linearity mapping, Chebyshev mapping with Logistic mapping in o...In this paper, we suggest one compound chaos image encryption method with time- varying multilevel initial parameters. This algorithm combines Subsection-linearity mapping, Chebyshev mapping with Logistic mapping in order to disturbing values of each image point and the array of original images based on chaotic second-scrambling way. The chaotic system uses time-varying system clock to change the first chaotic mapping initial parameter, and takes those chaotic sequences which generated by the first chaotic mapping as the initial parameters for the second chaotic mapping, then generate two-dimensional image pixel position scrambling matrix, and uses the same system clock to lock Chebyshev mapping initial parameter, then generate two-dimensional image pixel value transforming matrix. By this way for using the time-varying system clock, The encryption system can randomly changes many initial parameters of chaotic image encryption system to enhance image transmission security, has the capability of “one time one secret”. The simulation results show that this algorithm is simple, safe, easy to achieve with software and has huge secret key space.展开更多
Aerosol ammonium(NH_(4)^(+)),mainly produced from the reactions of ammonia(NH_(3))with acids in the atmosphere,has significant impacts on air pollution,radiative forcing,and human health.Understanding the source and f...Aerosol ammonium(NH_(4)^(+)),mainly produced from the reactions of ammonia(NH_(3))with acids in the atmosphere,has significant impacts on air pollution,radiative forcing,and human health.Understanding the source and formation mechanism of NH_(4)^(+)can provide scientific insights into air quality improvements.However,the sources of NH_(3)in urban areas are not well understood,and few studies focus on NH_(3)/NH_(4)^(+)at different heights within the atmospheric boundary layer,which hinders a comprehensive understanding of aerosol NH_(4)^(+).In this study,we perform both field observation and modeling studies(the Community Multiscale Air Quality,CMAQ)to investigate regional NH_(3)emission sources and vertically resolved NH_(4)^(+)formation mechanisms during the winter in Beijing.Both stable nitrogen isotope analyses and CMAQ model suggest that combustion-related NH_(3)emissions,including fossil fuel sources,NH_(3)slip,and biomass burning,are important sources of aerosol NH_(4)^(+)with more than 60%contribution occurring on heavily polluted days.In contrast,volatilization-related NH_(3)sources(livestock breeding,N-fertilizer application,and human waste)are dominant on clean days.Combustion-related NH_(3)is mostly local from Beijing,and biomass burning is likely an important NH_(3)source(~15%–20%)that was previously overlooked.More effective control strategies such as the two-product(e.g.,reducing both SO_(2)and NH_(3))control policy should be considered to improve air quality.展开更多
Importance:Neuroblastoma is the most common extracranial malignant solid tumor in children.Multidisciplinary care is critical to improving the survival of pediatric patients with neuroblastoma.Objective:To systematica...Importance:Neuroblastoma is the most common extracranial malignant solid tumor in children.Multidisciplinary care is critical to improving the survival of pediatric patients with neuroblastoma.Objective:To systematically summarize the clinical characteristics of children with neuroblastoma and evaluate their prognosis with multidisciplinary care provided in a single center.Methods:This retrospective study analyzed the clinical data of 1041 patients with neuroblastoma who were diagnosed,treated,and followed-up in the Hematology-Oncology Center of Beijing Children’s Hospital from 2007 to 2019.Results:The median age at diagnosis was 34 months;80.8%of the patients were younger than 5 years of age.Notably,243 patients(23.3%)were classified as low-risk,249 patients(23.9%)were classified as intermediate-risk,and 549(52.7%)were classified as high-risk.Furthermore,956 patients underwent surgical resections;986(94.7%)patients received chemotherapy;and 176 patients with high-risk neuroblastoma received hematopoietic stem cell transplantation.The 5-year event-free survival(EFS)rate was 91.3%and 5-year overall survival(OS)rate was 97.5%in low-risk group;in the intermediate-risk group,these rates were 85.1%and 96.7%,respectively,while they were 37.7%and 48.9%in the high-risk group(P<0.001 for both).The 5-year EFS and OS rates were significantly higher in patients diagnosed between 2015 and 2019 than in patients diagnosed between 2007 and 2014(P<0.001).In total,278 patients(26.7%)exhibited tumor relapse or progression;the median interval until relapse or progression was 14 months.Of the 233 patients who died,83%died of relapse or progression of neuroblastoma and 4.3%died of therapy-related complications.Interpretation:The 5-year OS rate was low in high-risk patients,compared with low-and intermediate-risk patients.Multidisciplinary care is critical for improvement of survival in pediatric patients with neuroblastoma.Additional treatment strategies should be sought to improve the prognosis of patients with high-risk neuroblastoma.展开更多
The studied mafic granulites are located at Xiwangshan,Xuanhua region in the north of the Trans-North China Orogen(TNCO),occurring as lens within tonalite-trondhjemite-granodiorite(TTG)gneisses in the eastern part of ...The studied mafic granulites are located at Xiwangshan,Xuanhua region in the north of the Trans-North China Orogen(TNCO),occurring as lens within tonalite-trondhjemite-granodiorite(TTG)gneisses in the eastern part of the Xiwangshan area.The rocks contain the representative granulite-facies minerals such as garnet,clinopyroxene,orthopyroxene,plagioclase,amphibolite,rutile and quartz,and also well-developed melt pseudomorph and antiperthite.Although the prograde metamorphic stage(M1)cannot be retrieved due to rare preservation of pre-peak-stage mineral associations,three distinct mineral assemblages that formed in different metamorphic stages can be identified,based on petrography and mineralogy characteristics.The peak stage(M2)is characterized by Grt2+Cpx2+Amp2+Pl2+Rt+melt pseudomorphs,and a post-peak decompression stage(M3)contains a mineral assemblage of Grt3+Opx3+Cpx3+Amp3+Pl3,while a later-retrogression stage(M4)is featured by coronas of Amp4+Pl4 surrounding garnet.By calculating metamorphic P-T conditions using THERMOCALC,stage M2 was constrained to be 13.2–14.8 kbar and 1050–1080℃,and M3 recorded P-T conditions of 5.7–7.3 kbar and 825–875℃,while M4 yielded P of^5 kbar and T of^660℃,consistent with amphibolite facies metamorphism.Taking into account of all these petrological data,we propose that the mafic granulite experienced a high-pressure(HP)and ultra-high temperature(UHT)granulite-facies metamorphism during the peak metamorphism,which was accompanied with a clockwise P-T path.U-Pb dating of metamorphic zircons in the granulites yields two groups of ages at 1853±14 and 1744±44 Ma,respectively.We suggest that the older age corresponded to the HP-UHT metamorphism,while the younger age represented an retrograde metamorphic event during cooling.展开更多
Alpha-thalassemia/mental retardation syndrome X-linked protein (ATRX) is a member of the switch 2/sucrose non- fermentable 2 (SWl2/SNF2) family of chromatin-remodelidg proteins (Clynes et al., 2013; Dyer et al., ...Alpha-thalassemia/mental retardation syndrome X-linked protein (ATRX) is a member of the switch 2/sucrose non- fermentable 2 (SWl2/SNF2) family of chromatin-remodelidg proteins (Clynes et al., 2013; Dyer et al., 2017).展开更多
基金the financial support from National Natural Science Foundation of China(Nos:52004095,51704119,and 21878161)the Natural Science Foundation of Hebei Province(E2017209243)Department of Education of Hebei Province(BJ2019038).
文摘In the era of serious greenhouse gas emission and energy shortage,it is necessary to use solid waste to prepare new renewable materials.In this work,the potential application of reed straw and electric furnace dust was explored.Firstly,magnetic carbon carrier(EFD&C)was prepared by high temperature calcination,and then magnetic carbon catalyst(SM@EFD&C)was prepared by activation of sodium methoxide.The catalyst was used to prepare biodiesel by transesterification reaction to test its activity and stability.Reed biochar,EFD&C and SM@EFD&C were detected by Diffraction of X-rays(XRD),Fourier transform infrared(FT-IR),Inductively coupled plasma(ICP),Scanning electron microscope(SEM),Transmission electron microscope(TEM),Brunauer-Emmett-Teller(BET),Vibrating sample magnetometer(VSM),Temperature programmed desorption of CO_(2)(CO_(2)-TPD)and Thermogravimetric analysis(TG-DTG).The results showed that SM@EFD&C catalyst had some characteristics including porous structure,easy adsorption and better magnetism.Under the reaction conditions of 65℃for 2 h with 6 wt%catalyst and methanol/oil molar ratio of 15:1,the biodiesel yields from reed biochar and EFD&C were only 4.88 wt%and 0.03 wt%,respectively,while the yield from SM@EFD&C catalyst reached 93.14 wt%(89.84 wt%after 7 cycles)under the same conditions,which proved that it had good catalytic activity and stability when used in biodiesel production.This study is of great significance of carbon dioxide emission reduction and environmental protection.
基金Supported by Integration and Demonstration Project of Simple and Efficient Cultivation Technology of Cotton(2020YFD1001000)Special Fund for Construction of Modern Agricultural Industrial Technology SystemProject of Hubei Agricultural Science and Technology Innovation Center(2019-620-000-06)
文摘[Objectives]To investigate the effect of low temperature treatment on cotton leaves at the two-leaf stage.[Methods]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Results]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Conclusions]These genes may play an important role in improving the cold resistance of cotton.
文摘In this paper, we suggest one compound chaos image encryption method with time- varying multilevel initial parameters. This algorithm combines Subsection-linearity mapping, Chebyshev mapping with Logistic mapping in order to disturbing values of each image point and the array of original images based on chaotic second-scrambling way. The chaotic system uses time-varying system clock to change the first chaotic mapping initial parameter, and takes those chaotic sequences which generated by the first chaotic mapping as the initial parameters for the second chaotic mapping, then generate two-dimensional image pixel position scrambling matrix, and uses the same system clock to lock Chebyshev mapping initial parameter, then generate two-dimensional image pixel value transforming matrix. By this way for using the time-varying system clock, The encryption system can randomly changes many initial parameters of chaotic image encryption system to enhance image transmission security, has the capability of “one time one secret”. The simulation results show that this algorithm is simple, safe, easy to achieve with software and has huge secret key space.
基金supported by the National Natural Science Foundation of China(42130513,41905110,and 41961130384)the Royal Society Newton Advanced Fellowship,United Kingdom(NAFR1191220)the Research Grants Council of the Hong Kong Special Administrative Region,China(T24/504/17 and A-Poly U502/16)。
文摘Aerosol ammonium(NH_(4)^(+)),mainly produced from the reactions of ammonia(NH_(3))with acids in the atmosphere,has significant impacts on air pollution,radiative forcing,and human health.Understanding the source and formation mechanism of NH_(4)^(+)can provide scientific insights into air quality improvements.However,the sources of NH_(3)in urban areas are not well understood,and few studies focus on NH_(3)/NH_(4)^(+)at different heights within the atmospheric boundary layer,which hinders a comprehensive understanding of aerosol NH_(4)^(+).In this study,we perform both field observation and modeling studies(the Community Multiscale Air Quality,CMAQ)to investigate regional NH_(3)emission sources and vertically resolved NH_(4)^(+)formation mechanisms during the winter in Beijing.Both stable nitrogen isotope analyses and CMAQ model suggest that combustion-related NH_(3)emissions,including fossil fuel sources,NH_(3)slip,and biomass burning,are important sources of aerosol NH_(4)^(+)with more than 60%contribution occurring on heavily polluted days.In contrast,volatilization-related NH_(3)sources(livestock breeding,N-fertilizer application,and human waste)are dominant on clean days.Combustion-related NH_(3)is mostly local from Beijing,and biomass burning is likely an important NH_(3)source(~15%–20%)that was previously overlooked.More effective control strategies such as the two-product(e.g.,reducing both SO_(2)and NH_(3))control policy should be considered to improve air quality.
基金Capital's Funds for Health Improvement and Research(No.CFH2018-2-2095)。
文摘Importance:Neuroblastoma is the most common extracranial malignant solid tumor in children.Multidisciplinary care is critical to improving the survival of pediatric patients with neuroblastoma.Objective:To systematically summarize the clinical characteristics of children with neuroblastoma and evaluate their prognosis with multidisciplinary care provided in a single center.Methods:This retrospective study analyzed the clinical data of 1041 patients with neuroblastoma who were diagnosed,treated,and followed-up in the Hematology-Oncology Center of Beijing Children’s Hospital from 2007 to 2019.Results:The median age at diagnosis was 34 months;80.8%of the patients were younger than 5 years of age.Notably,243 patients(23.3%)were classified as low-risk,249 patients(23.9%)were classified as intermediate-risk,and 549(52.7%)were classified as high-risk.Furthermore,956 patients underwent surgical resections;986(94.7%)patients received chemotherapy;and 176 patients with high-risk neuroblastoma received hematopoietic stem cell transplantation.The 5-year event-free survival(EFS)rate was 91.3%and 5-year overall survival(OS)rate was 97.5%in low-risk group;in the intermediate-risk group,these rates were 85.1%and 96.7%,respectively,while they were 37.7%and 48.9%in the high-risk group(P<0.001 for both).The 5-year EFS and OS rates were significantly higher in patients diagnosed between 2015 and 2019 than in patients diagnosed between 2007 and 2014(P<0.001).In total,278 patients(26.7%)exhibited tumor relapse or progression;the median interval until relapse or progression was 14 months.Of the 233 patients who died,83%died of relapse or progression of neuroblastoma and 4.3%died of therapy-related complications.Interpretation:The 5-year OS rate was low in high-risk patients,compared with low-and intermediate-risk patients.Multidisciplinary care is critical for improvement of survival in pediatric patients with neuroblastoma.Additional treatment strategies should be sought to improve the prognosis of patients with high-risk neuroblastoma.
基金supported by the National Natural Science Foundation of China (No. 41761144061)the Shandong Provincial Natural Science Foundation (No. ZR2016DM04)the University Students Innovation Program of SDUST (No. 2015TDJH101)
文摘The studied mafic granulites are located at Xiwangshan,Xuanhua region in the north of the Trans-North China Orogen(TNCO),occurring as lens within tonalite-trondhjemite-granodiorite(TTG)gneisses in the eastern part of the Xiwangshan area.The rocks contain the representative granulite-facies minerals such as garnet,clinopyroxene,orthopyroxene,plagioclase,amphibolite,rutile and quartz,and also well-developed melt pseudomorph and antiperthite.Although the prograde metamorphic stage(M1)cannot be retrieved due to rare preservation of pre-peak-stage mineral associations,three distinct mineral assemblages that formed in different metamorphic stages can be identified,based on petrography and mineralogy characteristics.The peak stage(M2)is characterized by Grt2+Cpx2+Amp2+Pl2+Rt+melt pseudomorphs,and a post-peak decompression stage(M3)contains a mineral assemblage of Grt3+Opx3+Cpx3+Amp3+Pl3,while a later-retrogression stage(M4)is featured by coronas of Amp4+Pl4 surrounding garnet.By calculating metamorphic P-T conditions using THERMOCALC,stage M2 was constrained to be 13.2–14.8 kbar and 1050–1080℃,and M3 recorded P-T conditions of 5.7–7.3 kbar and 825–875℃,while M4 yielded P of^5 kbar and T of^660℃,consistent with amphibolite facies metamorphism.Taking into account of all these petrological data,we propose that the mafic granulite experienced a high-pressure(HP)and ultra-high temperature(UHT)granulite-facies metamorphism during the peak metamorphism,which was accompanied with a clockwise P-T path.U-Pb dating of metamorphic zircons in the granulites yields two groups of ages at 1853±14 and 1744±44 Ma,respectively.We suggest that the older age corresponded to the HP-UHT metamorphism,while the younger age represented an retrograde metamorphic event during cooling.
文摘Alpha-thalassemia/mental retardation syndrome X-linked protein (ATRX) is a member of the switch 2/sucrose non- fermentable 2 (SWl2/SNF2) family of chromatin-remodelidg proteins (Clynes et al., 2013; Dyer et al., 2017).