This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS...This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at perihelion.The absolute magnitude of comets ATLAS and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 respectively.The cometary activity of comets ATLAS and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means that they could remain active until the second half of 2026.The nucleus of comet ATLAS has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little larger.The c-o colors of the comets ATLAS and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP 1194.These comets showed a bluish trend in the coma color with decreasing heliocentric distance.Comet Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of dust.The slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign.展开更多
Sodium-ion batteries(SIBs)have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium-ion batteries(LIBs).Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)as a common cathode of SIBs,featur...Sodium-ion batteries(SIBs)have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium-ion batteries(LIBs).Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)as a common cathode of SIBs,features the merits of high operating voltage,small volume change and favorable specific energy density.However,it suffers from poor cycling stability and rate performance induced by its low intrinsic conductivity.Herein,we propose an ingenious strategy targeting superior SIBs through cross-linked NVPF with multi-dimensional nanocarbon frameworks composed of amorphous carbon and carbon nanotubes(NVPF@C@CNTs).This rational design ensures favorable particle size for shortened sodium ion transmission pathway as well as improved electronic transfer network,thus leading to enhanced charge transfer kinetics and superior cycling stability.Benefited from this unique structure,significantly improved electrochemical properties are obtained,including high specific capacity(126.9 mAh g^(-1)at 1 C,1 C=128 mA g^(-1))and remarkably improved long-term cycling stability with 93.9%capacity retention after 1000 cycles at 20 C.The energy density of 286.8 Wh kg^(-1)can be reached for full cells with hard carbon as anode(NVPF@C@CNTs//HC).Additionally,the electrochemical performance of the full cell at high temperature is also investigated(95.3 mAh g^(-1)after 100 cycles at 1 C at 50℃).Such nanoscale dual-carbon networks engineering and thorough discussion of ion diffusion kinetics might make contributions to accelerating the process of phosphate cathodes in SIBs for large-scale energy storages.展开更多
为了评估转基因大豆向野大豆(Glycine soja Sieb.et Zucc.)基因漂移后可能产生的生态风险,选取抗草甘膦转基因大豆(携带外源基因cp4-epsps)与野大豆(来自内蒙古包头)杂交F_(2)代种皮颜色为黑色、褐绿色和褐黄色(与野大豆种皮颜色相近)...为了评估转基因大豆向野大豆(Glycine soja Sieb.et Zucc.)基因漂移后可能产生的生态风险,选取抗草甘膦转基因大豆(携带外源基因cp4-epsps)与野大豆(来自内蒙古包头)杂交F_(2)代种皮颜色为黑色、褐绿色和褐黄色(与野大豆种皮颜色相近)的种子,对这些种子萌发产生的F_(3)代植株的19个定量性状和5个定性性状进行分析,在此基础上,将F_(3)代植株及其亲本进行聚类分析,并对不同组F_(3)代的定量和定性性状进行分析。结果显示:F_(3)代幼苗中抗性植株与非抗性植株的分离比符合“5∶1”的孟德尔遗传定律。定量性状中,结实率的变异系数最小(4.65%),其余18个性状的变异系数高于14%,其中,单株种子数的变异系数最大(55.68%)。不同种皮颜色F_(2)代种子萌发产生的F_(3)代植株均以强缠绕型占比最高;F_(3)代植株中,90.7%的果荚为弯镰形或弓形,且80.0%的果荚颜色为黑褐色;黑色种皮F_(2)代种子萌发产生的F_(3)代种皮颜色无性状分离,褐绿色和褐黄色种皮F_(2)代种子萌发产生的F_(3)代种皮颜色均出现性状分离;F_(3)代种子中,82.7%的种子有泥膜。聚类结果显示F_(3)代植株被分为3组。不同组F_(3)代中,Ⅰ组的多数性状最低,且株高等5个性状显著低于野大豆;Ⅱ组的9个性状最高,且单株结荚数等15个性状显著高于野大豆,仅株高显著低于野大豆;Ⅲ组的部分性状最高,且单株结荚数等12个性状显著高于野大豆,株高等3个性状显著低于野大豆。综合比较认为,Ⅱ组的竞争能力最强,Ⅰ组的竞争能力最弱。Ⅰ组的不缠绕型植株占比最高,而Ⅱ和Ⅲ组的强缠绕型植株占比最高。3组F_(3)代的种皮颜色均以黑色占比最高。综上所述,供试的不同组F_(3)代植株均能完成生活史并产生后代。若抗草甘膦转基因大豆的基因通过花粉漂移到野大豆上并成功杂交,则会产生不同适应性杂交后代,增加生态风险。展开更多
Background:Patients with pancreatic ductal adenocarcinoma(PDAC)who undergo surgical resection and receive effective chemotherapy have the best chance for longterm survival.Unfortunately,because of the heterogeneity of...Background:Patients with pancreatic ductal adenocarcinoma(PDAC)who undergo surgical resection and receive effective chemotherapy have the best chance for longterm survival.Unfortunately,because of the heterogeneity of pancreatic cancer,it is difficult to find a personalized treatment strategy for patients.Organoids are ideal preclinical models for personalized medicine.Therefore,we explore the cultivation conditions and construction methods of PDAC organoid models to screen the individualized therapy strategy.Methods:Fresh PDAC tissues from surgical resection were collected and digested with digestive enzymes;then the tumor cells were embedded in Matrigel with a suitable medium to establish the PDAC organoid models.The genetic stability of the organoids was analyzed using whole exon sequencing;hematoxylin and eosin staining and immunohistochemistry of organoids were performed to analyze their consistency with the pathological morphology of the patient's tumor tissue;After 2 days of organoid culture,we selected four commonly used clinical chemotherapy drugs for single or combined treatment to analyze drug sensitivity.Results:Two cases of PDAC organoid models were successfully established,and the results of their pathological characteristics and exome sequencing were consistent with those of the patient's tumor tissue.Both PDAC organoids showed more sensitivity to gemcitabine and cisplatin,and the combined treatment was more effective than monotherapy.Conclusion:Both organoids better retained the pathological characteristics,genomic stability,and heterogeneity with the original tumor.Individual PDAC organoids exhibited different sensitivities to the same drugs.Thus,this study provided ideal experimental models for screening individualized therapy strategy for patients with PDAC.展开更多
基金The ATLAS project is primarily funded to search for near-earth asteroids through NASA grants NN12AR55G,80NSSC18K0284,and 80NSSC18K1575funded by Kepler/K2 grant J1944/80NSSC19K0112 and HST GO-15889,and STFC grants ST/T000198/1 and ST/S006109/1。
文摘This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at perihelion.The absolute magnitude of comets ATLAS and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 respectively.The cometary activity of comets ATLAS and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means that they could remain active until the second half of 2026.The nucleus of comet ATLAS has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little larger.The c-o colors of the comets ATLAS and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP 1194.These comets showed a bluish trend in the coma color with decreasing heliocentric distance.Comet Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of dust.The slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign.
基金financially supported by Science and Technology Foundation of Guizhou Province(QKHZC[2020]2Y037)the Science and Technology Innovation Program of Hunan Province(2020RC4005,2019RS1004)+2 种基金Research start-up funding from Central South University(202044019)Innovation Mover Program of Central South University(2020CX007)National Natural Science Foundation of China(U21A20284)
文摘Sodium-ion batteries(SIBs)have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium-ion batteries(LIBs).Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)as a common cathode of SIBs,features the merits of high operating voltage,small volume change and favorable specific energy density.However,it suffers from poor cycling stability and rate performance induced by its low intrinsic conductivity.Herein,we propose an ingenious strategy targeting superior SIBs through cross-linked NVPF with multi-dimensional nanocarbon frameworks composed of amorphous carbon and carbon nanotubes(NVPF@C@CNTs).This rational design ensures favorable particle size for shortened sodium ion transmission pathway as well as improved electronic transfer network,thus leading to enhanced charge transfer kinetics and superior cycling stability.Benefited from this unique structure,significantly improved electrochemical properties are obtained,including high specific capacity(126.9 mAh g^(-1)at 1 C,1 C=128 mA g^(-1))and remarkably improved long-term cycling stability with 93.9%capacity retention after 1000 cycles at 20 C.The energy density of 286.8 Wh kg^(-1)can be reached for full cells with hard carbon as anode(NVPF@C@CNTs//HC).Additionally,the electrochemical performance of the full cell at high temperature is also investigated(95.3 mAh g^(-1)after 100 cycles at 1 C at 50℃).Such nanoscale dual-carbon networks engineering and thorough discussion of ion diffusion kinetics might make contributions to accelerating the process of phosphate cathodes in SIBs for large-scale energy storages.
文摘为了评估转基因大豆向野大豆(Glycine soja Sieb.et Zucc.)基因漂移后可能产生的生态风险,选取抗草甘膦转基因大豆(携带外源基因cp4-epsps)与野大豆(来自内蒙古包头)杂交F_(2)代种皮颜色为黑色、褐绿色和褐黄色(与野大豆种皮颜色相近)的种子,对这些种子萌发产生的F_(3)代植株的19个定量性状和5个定性性状进行分析,在此基础上,将F_(3)代植株及其亲本进行聚类分析,并对不同组F_(3)代的定量和定性性状进行分析。结果显示:F_(3)代幼苗中抗性植株与非抗性植株的分离比符合“5∶1”的孟德尔遗传定律。定量性状中,结实率的变异系数最小(4.65%),其余18个性状的变异系数高于14%,其中,单株种子数的变异系数最大(55.68%)。不同种皮颜色F_(2)代种子萌发产生的F_(3)代植株均以强缠绕型占比最高;F_(3)代植株中,90.7%的果荚为弯镰形或弓形,且80.0%的果荚颜色为黑褐色;黑色种皮F_(2)代种子萌发产生的F_(3)代种皮颜色无性状分离,褐绿色和褐黄色种皮F_(2)代种子萌发产生的F_(3)代种皮颜色均出现性状分离;F_(3)代种子中,82.7%的种子有泥膜。聚类结果显示F_(3)代植株被分为3组。不同组F_(3)代中,Ⅰ组的多数性状最低,且株高等5个性状显著低于野大豆;Ⅱ组的9个性状最高,且单株结荚数等15个性状显著高于野大豆,仅株高显著低于野大豆;Ⅲ组的部分性状最高,且单株结荚数等12个性状显著高于野大豆,株高等3个性状显著低于野大豆。综合比较认为,Ⅱ组的竞争能力最强,Ⅰ组的竞争能力最弱。Ⅰ组的不缠绕型植株占比最高,而Ⅱ和Ⅲ组的强缠绕型植株占比最高。3组F_(3)代的种皮颜色均以黑色占比最高。综上所述,供试的不同组F_(3)代植株均能完成生活史并产生后代。若抗草甘膦转基因大豆的基因通过花粉漂移到野大豆上并成功杂交,则会产生不同适应性杂交后代,增加生态风险。
基金Laboratory Animal Foundation Program,Grant/Award Number:SYDW_KY 2021-14National Natural Science Foundation of China,Grant/Award Number:32070532 and 32270566+1 种基金Promotion Plan of the Air Force Medical University,Grant/Award Number:2020SWAQ11the Ethics Committee of Xijing Hospital of FMMU(ethics approval number:KY20203128-1).
文摘Background:Patients with pancreatic ductal adenocarcinoma(PDAC)who undergo surgical resection and receive effective chemotherapy have the best chance for longterm survival.Unfortunately,because of the heterogeneity of pancreatic cancer,it is difficult to find a personalized treatment strategy for patients.Organoids are ideal preclinical models for personalized medicine.Therefore,we explore the cultivation conditions and construction methods of PDAC organoid models to screen the individualized therapy strategy.Methods:Fresh PDAC tissues from surgical resection were collected and digested with digestive enzymes;then the tumor cells were embedded in Matrigel with a suitable medium to establish the PDAC organoid models.The genetic stability of the organoids was analyzed using whole exon sequencing;hematoxylin and eosin staining and immunohistochemistry of organoids were performed to analyze their consistency with the pathological morphology of the patient's tumor tissue;After 2 days of organoid culture,we selected four commonly used clinical chemotherapy drugs for single or combined treatment to analyze drug sensitivity.Results:Two cases of PDAC organoid models were successfully established,and the results of their pathological characteristics and exome sequencing were consistent with those of the patient's tumor tissue.Both PDAC organoids showed more sensitivity to gemcitabine and cisplatin,and the combined treatment was more effective than monotherapy.Conclusion:Both organoids better retained the pathological characteristics,genomic stability,and heterogeneity with the original tumor.Individual PDAC organoids exhibited different sensitivities to the same drugs.Thus,this study provided ideal experimental models for screening individualized therapy strategy for patients with PDAC.
