Transition metal-doped CeO_(2)catalysts exhibit great potentials for the selective catalytic reduction(SCR)of nitrogen oxide(NOx)with NH_(3)(NH_(3)-SCR).However,traditional research mainly relies on a lot of experimen...Transition metal-doped CeO_(2)catalysts exhibit great potentials for the selective catalytic reduction(SCR)of nitrogen oxide(NOx)with NH_(3)(NH_(3)-SCR).However,traditional research mainly relies on a lot of experiments to find out effective catalysts,which wastes a lot of time and resources.Screening out effective CeO_(2)-based catalysts for low-temperature NH_(3)-SCR via density functional theory(DFT)calculations is crucial for the rational design and synthesis of efficient catalysts.Herein,transition metal(M=Co,Cr,Cu,Fe,Mn,Mo,Nb,Ni,Ta,Ti,V,and W)-doped CeO_(2)catalysts were screened out via accelerated DFT calculations for NH_(3)-SCR of nitric-oxide(NO)using three theoretical terms;(i)an adsorption energy of NH_(3),(ii)an adsorption energy of NO,and(iii)the reaction energies between NO with O_(2)and lattice oxygen.The theoretically predicted trend in catalytic performance is as follows:CeO_(2)-Mn,-Cu,-Mo>CeO_(2)-Fe,-Co,-Ni,-V,-Cr>CeO_(2)-W,-Ti>CeO_(2)-Nb,-Ta.The theoretical prediction was well verified via experimental NH_(3)-SCR activity of NO at low temperatures(90–300℃),demonstrating CeO_(2)-Mo as efficient NH_(3)-SCR catalyst across a broad temperature range.Temperature-programmed desorption of NH_(3)and in situ diffuse reflectance infrared Fourier transforms spectroscopy further indicated that metal doping significantly enhanced the NH_(3)adsorption capacity and strength of CeO_(2)in the medium-to low-temperature range.Consequently,accelerated DFT calculations provide a useful tool with great potentials for predicting the catalytic performance.展开更多
Constructing clus ter heterostructures with strongly coupled interfaces is of great importance to accelerating the catalytic reactions that involve multiple intermediates.Herein,a strongly coupled cluster heterostruct...Constructing clus ter heterostructures with strongly coupled interfaces is of great importance to accelerating the catalytic reactions that involve multiple intermediates.Herein,a strongly coupled cluster heterostructure composed of platinum and molybdenum carbide(Pt@Mo_(2)C)derived from polyoxometalate clusters is designed to achieve excellent alkaline hydrogen evolution reaction.The Pt@Mo_(2)C cluster exhibits strong electronic interactions between Pt and Mo_(2)C,working together to facilitate the H_(2)O dissociation by concurrently binding intermediates(Pt-H*and Mo-OH*),thus accelerating the kinetics of the rate-determining Volmer step.Theoptimized Pt@Mo_(2)C exhibits a high mass activity of12.1 A·mgpt^(-1),19.2 times higher than that of 20%Pt/C in alkaline media.Moreover,it can be stabilized at a current density of 100 mA·cm^(-2)for more than 200 h.This work demonstrated the superiority of the cluster heterostructures and co-catalytic effect towards the development of highly efficient electrocatalysts.展开更多
Basophils,which are considered as redundant relatives of mast cells and the rarest granulocytes in peripheral circulation,have been neglected by researchers in the past decades.Previous studies have revealed their vit...Basophils,which are considered as redundant relatives of mast cells and the rarest granulocytes in peripheral circulation,have been neglected by researchers in the past decades.Previous studies have revealed their vital roles in allergic diseases and parasitic infections.Intriguingly,recent studies even reported that basophils might be associated with cancer development,as activated basophils synthesize and release a variety of cytokines and chemokines in response to cancers.However,it is still subject to debate whether basophils function as tumor-protecting or tumor-promoting components;the answer may depend on the tumor biology and the microenvironment.Herein,we reviewed the role of basophils in cancers,and highlighted some potential and promising therapeutic strategies.展开更多
It is suggested that Δ6 fatty acid desaturase(FAD) plays a critical role in the biosynthesis of polyunsaturated fatty acids in plants and microalgae. But why does it adapt to the changed environments such as nitrogen...It is suggested that Δ6 fatty acid desaturase(FAD) plays a critical role in the biosynthesis of polyunsaturated fatty acids in plants and microalgae. But why does it adapt to the changed environments such as nitrogen starvation is seldom understood. One Δ6 FAD gene( MiD6 fad) from an arachidonic acidrich microalga M yrmecia incisa Reisigl(Chlorophyta) was first heterologously expressed in S accharomyces cerevisiae for the identification of function. The fatty acid profile of transgenic yeast detected by gas chromatography-mass spectrometry illustrated that the enzyme MiD6 FAD could convert linoleic and ?-linolenic acids to γ-linolenic and stearidonic acids, respectively, demonstrating that M iD6 fad encoded a Δ6 FAD. A 1 965-bp fragment of the cloned 2 347-bp 5′-upstream region of M iD6 fad was next subcloned and fused upstream with green fluorescent protein(GFP) gene to replace the GAL1 promoter of the vector pYES2. The generated construct was transformed into S. cerevisiae for function determination. Confocal microscopic images of the transformed line illustrated that this inserted fragment could drive GFP expression, which was further verified by fluorescence intensity quantification and Western blot analysis using antiGFP antibody. The conversion efficiency(approximately 2%-3%) of MiD6 FAD was much lower than the reported ? 3 FAD and Δ6 elongase in this microalga, suggesting that MiD6 FAD catalysed the possible ratelimiting step for ArA biosynthesis. The presence of several putative c is-acting regulatory elements in this identified promoter sheds new light on the regulation mechanism research of Δ6 FAD transcription for the ArA production in M. incisa in changing environmental factors.展开更多
Insight into the growth behavior and electronic regulation of platinum(Pt)on various transition metal supports is paramount in developing high-performing electrocatalysts for hydrogen evolution reactions(HER).Herein,w...Insight into the growth behavior and electronic regulation of platinum(Pt)on various transition metal supports is paramount in developing high-performing electrocatalysts for hydrogen evolution reactions(HER).Herein,we studied the influence of molybdenum-based supports(MoX,X=C,N,P,and S)on the growth behavior and electronic regulation of Pt.We found that the formation energy variations between Pt single atom and clusters on MoX supports play a pivotal role in the growth behavior of Pt.Moreover,the electronic regulation of Pt induced by metal-support interaction may reflect the valence changes of Pt in PtMoX/C.The Pt-MoC/C catalyst with a moderate valence state of Pt exhibits the best HER activity with an overpotential of 12.0 mV at 10 mA cm^(-2)and a mass activity of 27.1 A mg_(Pt)^(-)1,12.3 times as high as that of commercial 20 wt%Pt/C.This work provides constructive guidance for the design of high-performance HER catalysts.展开更多
Background:Limited knowledge and guidelines exist for invasive intraductal papillary mucinous neoplasm(IPMN).This study aims to explore the significance of lymph node involvement on adjuvant chemotherapy(ACT)for invas...Background:Limited knowledge and guidelines exist for invasive intraductal papillary mucinous neoplasm(IPMN).This study aims to explore the significance of lymph node involvement on adjuvant chemotherapy(ACT)for invasive IPMN.Materials and methods:Patients diagnosed with invasive IPMN were selected from both the Surveillance,Epidemiology,and End Results(SEER)database and our hospital.Kaplan-Meier analysis,Cox proportional hazards model,and propensity score matching(PSM)were used in this study.Results:In the SEER group,multivariate analysis involving 775 patients revealed that several factors including age,tumor differentiation,the American Joint Committee on Cancer(AJCC)T staging,N staging,and tumor node metastasis classification(TNM)stage significantly influenced overall survival(OS)and cancer-specific survival(CSS).Turning to the Zhongshan Hospital group(ZS group),which had 94 recruited patients,multivariate analysis for OS,CSS,and recurrence-free survival(RFS)showed that AJCC N staging emerged as the most significant risk factor,with hazard ratio(HR)values of 4.664,4.955,and 3.175,respectively.In subgroup analysis,ACT provided survival advantages for patients with positive lymph node metastasis(LNM).In a PSM analysis focused on patients with positive LNM,the comparison revealed that ACT emerged as a critical factor influencing both OS and CSS(both P<.005).Especially,these patients younger than 60 years old or those with AJCC-T2-N+staging were found to get apparently benefit from ACT as revealed by our subgroup interaction analysis.Conclusion:LNM plays a pivotal role in the management of invasive IPMN patients who underwent surgery,and ACT might be a beneficial therapeutic option for individuals concurrent with LNM,particularly among those younger than 60 years old,or with AJCC-T2-N+staging.展开更多
The extraction and complexation of trivalent Am(Ⅲ)and lanthanide(Ⅲ)with a new phenanthroline-derived phosphonate ligand,tetrabutyl-(1,10-phenanthrolin-2,9-diyl)phosphonate(C4-POPhen),were investigated by solvent ext...The extraction and complexation of trivalent Am(Ⅲ)and lanthanide(Ⅲ)with a new phenanthroline-derived phosphonate ligand,tetrabutyl-(1,10-phenanthrolin-2,9-diyl)phosphonate(C4-POPhen),were investigated by solvent extraction,absorption spectroscopy,NMR titration,luminescence spectroscopy,and theoretical computation.Selective extraction of Am(Ⅲ)over Eu(Ⅲ)from highly acidic HNO_(3) solution(up to 3.0 M)with good selectivity and a fast extraction rate was achieved by using the C4-POPhen ligand.The 1:2 metal/ligand complex was found to be the predominant species in the extracted organic phase by a slope analysis method.NMR titration results demonstrated that only a 1:1 complex of C4-POPhen with Ln(NO_(3))_(3) was formed in a CH_(3)OH system,while two complexes(1:1 and 1:2)were found when using Ln(ClO_(4))_(3) as the metal salts instead of Ln(NO_(3))3.The stability constants of the C4-POPhen/Am(Ⅲ)and C4-POPhen/Ln(Ⅲ)complexes in CH3OH with perchlorate and nitrate were determined by absorption spectroscopy.The Am(Ⅲ)complexes exhibited higher complexation ability than Ln(Ⅲ),which was consistent with the extraction results.DFT calculations also suggested that the Am–N bonds in C4-POPhen/Am(Ⅲ)complexes had a higher degree of covalence than the Eu–N bonds in C4-POPhen/Eu(Ⅲ)complexes,revealing the underlying driving force for the extraction selectivity of Am(Ⅲ)over Eu(Ⅲ)by C4-POPhen.These results indicate that phenanthroline-derived phosphate ligands may serve as promising candidates for separation of trivalent actinides over lanthanides from highly active nuclear waste.展开更多
In the extraction of lanthanides by the sulfur donor ligand,Cyanex 301(HC301,bis(2,4,4-trimethylpentyl)dithiophosphinic acid),a transition in the coordination mode of extracted complexes has been observed between Eu a...In the extraction of lanthanides by the sulfur donor ligand,Cyanex 301(HC301,bis(2,4,4-trimethylpentyl)dithiophosphinic acid),a transition in the coordination mode of extracted complexes has been observed between Eu and Gd.The light lanthanides La-Eu tend to be extracted as inner sphere complexes with HC301 directly coordinating the metal whereas the second half of the series Gd-Lu have a tendency to be extracted as outer sphere complexes.Without extended actinide studies,spanning the transplutonium actinides,it was unclear if a similar change in the extraction mechanism occurs in the actinide series.To assess this,solvent extraction studies were completed examining the slope dependence of the actinides and lathanides in the presence of varied nitrate and acid concentrations.Significant variation in the slope dependences was not observed for either the actinides or the lanthanides as pC_(H+)varied,however,the nitrate dependence and neodymium spectroscopy data suggest that the formation of outer sphere complexes is suppressed by higher nitrate concentrations.This suppression of outer sphere complexes enhanced the extraction of lanthanides,but not the actinides and suggests that the actinides form inner sphere complexes.Therefore,the HC301 separations chemistry observed thus far suggest differences in the chemistry of the actinides and lanthanides continues to persist deep into the actinide series.展开更多
Pancreatic ductal adenocarcinoma is the known kind of tumor biologically featured as high malignant degree, lack of effective methods for diagnosis and treatment, which reflects its unpleasant prognosis. Recently, wit...Pancreatic ductal adenocarcinoma is the known kind of tumor biologically featured as high malignant degree, lack of effective methods for diagnosis and treatment, which reflects its unpleasant prognosis. Recently, with the breakthrough of burgeoning therapeutic methods, the flush of dawn for pancreatic cancer nearly arrives. Nowadays, besides surgery, neoadjuvant chemoradiotherapy, tumor vaccine therapy, and immunotherapy all show their active situation and obtain certain clinical efficacy, but that is still limited to pancreatic cancer. However, the appearance and development of programmed cell death-1 (PD-1) immune checkpoint inhibitor may final improve survival of pancreatic cancer. This article aims to deeply understand the value of PD-1 immune checkpoint inhibitor in pancreatic cancer and validly provide the evidence for treatment by means of performing a systematic review on the current status in the fields of the mechanism and application of anti-PD-1 in pancreatic cancer, associations with surgery, PD- 1-related side effects and prospections.展开更多
基金financially supported by the National Key R&D Program of China(Nos.2021YFC1910504 and 2024YFC3907701)the National Energy-Saving and Low-Carbon Materials Production and Application Demonstration Platform Program(No.TC220H06N)+2 种基金the Fundamental Research Funds for the Central Universities(No.FRF-EYIT-23-07)the National Natural Science Foundation of China(No.52204412)Beijing Natural Science Foundation(No.2242046)
文摘Transition metal-doped CeO_(2)catalysts exhibit great potentials for the selective catalytic reduction(SCR)of nitrogen oxide(NOx)with NH_(3)(NH_(3)-SCR).However,traditional research mainly relies on a lot of experiments to find out effective catalysts,which wastes a lot of time and resources.Screening out effective CeO_(2)-based catalysts for low-temperature NH_(3)-SCR via density functional theory(DFT)calculations is crucial for the rational design and synthesis of efficient catalysts.Herein,transition metal(M=Co,Cr,Cu,Fe,Mn,Mo,Nb,Ni,Ta,Ti,V,and W)-doped CeO_(2)catalysts were screened out via accelerated DFT calculations for NH_(3)-SCR of nitric-oxide(NO)using three theoretical terms;(i)an adsorption energy of NH_(3),(ii)an adsorption energy of NO,and(iii)the reaction energies between NO with O_(2)and lattice oxygen.The theoretically predicted trend in catalytic performance is as follows:CeO_(2)-Mn,-Cu,-Mo>CeO_(2)-Fe,-Co,-Ni,-V,-Cr>CeO_(2)-W,-Ti>CeO_(2)-Nb,-Ta.The theoretical prediction was well verified via experimental NH_(3)-SCR activity of NO at low temperatures(90–300℃),demonstrating CeO_(2)-Mo as efficient NH_(3)-SCR catalyst across a broad temperature range.Temperature-programmed desorption of NH_(3)and in situ diffuse reflectance infrared Fourier transforms spectroscopy further indicated that metal doping significantly enhanced the NH_(3)adsorption capacity and strength of CeO_(2)in the medium-to low-temperature range.Consequently,accelerated DFT calculations provide a useful tool with great potentials for predicting the catalytic performance.
基金supported by the National Natural Science Foundation of China(Nos.22171287 and 52303274)Taishan Scholar Project of Shandong Province(No.tsqn202103046)+2 种基金Natural Science Foundation of Shandong Province(No.ZR2022QE175)Young Innovative Science and Technology Support Program for Universities of Shandong Province,P.R.China(Nos.2023KJ280 and 2021KJ014)Fundamental Research Funds for the Central Universities(Nos.24CX07007A and 22CX01002A-1)
文摘Constructing clus ter heterostructures with strongly coupled interfaces is of great importance to accelerating the catalytic reactions that involve multiple intermediates.Herein,a strongly coupled cluster heterostructure composed of platinum and molybdenum carbide(Pt@Mo_(2)C)derived from polyoxometalate clusters is designed to achieve excellent alkaline hydrogen evolution reaction.The Pt@Mo_(2)C cluster exhibits strong electronic interactions between Pt and Mo_(2)C,working together to facilitate the H_(2)O dissociation by concurrently binding intermediates(Pt-H*and Mo-OH*),thus accelerating the kinetics of the rate-determining Volmer step.Theoptimized Pt@Mo_(2)C exhibits a high mass activity of12.1 A·mgpt^(-1),19.2 times higher than that of 20%Pt/C in alkaline media.Moreover,it can be stabilized at a current density of 100 mA·cm^(-2)for more than 200 h.This work demonstrated the superiority of the cluster heterostructures and co-catalytic effect towards the development of highly efficient electrocatalysts.
基金supported by the Shanghai Sailing Program(No.21YF1407100)the China Postdoctoral Science Foundation(No.2021M690037)+1 种基金the National Natural Science Foundation of China(Nos.82103409 and 81773068)the National Key R&D Program of China(No.2019YFC1315902)。
文摘Basophils,which are considered as redundant relatives of mast cells and the rarest granulocytes in peripheral circulation,have been neglected by researchers in the past decades.Previous studies have revealed their vital roles in allergic diseases and parasitic infections.Intriguingly,recent studies even reported that basophils might be associated with cancer development,as activated basophils synthesize and release a variety of cytokines and chemokines in response to cancers.However,it is still subject to debate whether basophils function as tumor-protecting or tumor-promoting components;the answer may depend on the tumor biology and the microenvironment.Herein,we reviewed the role of basophils in cancers,and highlighted some potential and promising therapeutic strategies.
基金Supported by the National Natural Science Foundation of China(No.31172389)the Special Project of Marine Renewable Energy from the State Oceanic Administration(No.SHME2011SW02)the Shanghai Universities Peak Discipline Project of Aquaculture
文摘It is suggested that Δ6 fatty acid desaturase(FAD) plays a critical role in the biosynthesis of polyunsaturated fatty acids in plants and microalgae. But why does it adapt to the changed environments such as nitrogen starvation is seldom understood. One Δ6 FAD gene( MiD6 fad) from an arachidonic acidrich microalga M yrmecia incisa Reisigl(Chlorophyta) was first heterologously expressed in S accharomyces cerevisiae for the identification of function. The fatty acid profile of transgenic yeast detected by gas chromatography-mass spectrometry illustrated that the enzyme MiD6 FAD could convert linoleic and ?-linolenic acids to γ-linolenic and stearidonic acids, respectively, demonstrating that M iD6 fad encoded a Δ6 FAD. A 1 965-bp fragment of the cloned 2 347-bp 5′-upstream region of M iD6 fad was next subcloned and fused upstream with green fluorescent protein(GFP) gene to replace the GAL1 promoter of the vector pYES2. The generated construct was transformed into S. cerevisiae for function determination. Confocal microscopic images of the transformed line illustrated that this inserted fragment could drive GFP expression, which was further verified by fluorescence intensity quantification and Western blot analysis using antiGFP antibody. The conversion efficiency(approximately 2%-3%) of MiD6 FAD was much lower than the reported ? 3 FAD and Δ6 elongase in this microalga, suggesting that MiD6 FAD catalysed the possible ratelimiting step for ArA biosynthesis. The presence of several putative c is-acting regulatory elements in this identified promoter sheds new light on the regulation mechanism research of Δ6 FAD transcription for the ArA production in M. incisa in changing environmental factors.
基金supported by the National Natural Science Foundation of China(22171287,51972342,52303274,51902345)the Taishan Scholar Project of Shandong Province(tsqn202103046 and ts20190922)+1 种基金the Natural Science Foundation of Shandong Province(ZR2022QE175)the Fundamental Research Funds for the Central Universities(24CX07007A and 22CX01002A-1)。
文摘Insight into the growth behavior and electronic regulation of platinum(Pt)on various transition metal supports is paramount in developing high-performing electrocatalysts for hydrogen evolution reactions(HER).Herein,we studied the influence of molybdenum-based supports(MoX,X=C,N,P,and S)on the growth behavior and electronic regulation of Pt.We found that the formation energy variations between Pt single atom and clusters on MoX supports play a pivotal role in the growth behavior of Pt.Moreover,the electronic regulation of Pt induced by metal-support interaction may reflect the valence changes of Pt in PtMoX/C.The Pt-MoC/C catalyst with a moderate valence state of Pt exhibits the best HER activity with an overpotential of 12.0 mV at 10 mA cm^(-2)and a mass activity of 27.1 A mg_(Pt)^(-)1,12.3 times as high as that of commercial 20 wt%Pt/C.This work provides constructive guidance for the design of high-performance HER catalysts.
基金supported by grants from the Shanghai Municipal Health Commission(201940019)National Natural Science Foundation of China(82103417,81827807,81972218,81972257,82103409,82173116,82273382,82272929)+5 种基金Shanghai ShenKang Hospital Development Centre Project(SHDC2020CR2017B)Program of Shanghai Academic/Technology Research Leader(23XD1400600)China Postdoctoral Science Foundation(2021M690037)Shanghai Sailing Program(21YF1407100)Science and Technology Planning Project of Yunnan Province(202305AF150148)Shanghai Municipal Health Commission(20224Y0307).
文摘Background:Limited knowledge and guidelines exist for invasive intraductal papillary mucinous neoplasm(IPMN).This study aims to explore the significance of lymph node involvement on adjuvant chemotherapy(ACT)for invasive IPMN.Materials and methods:Patients diagnosed with invasive IPMN were selected from both the Surveillance,Epidemiology,and End Results(SEER)database and our hospital.Kaplan-Meier analysis,Cox proportional hazards model,and propensity score matching(PSM)were used in this study.Results:In the SEER group,multivariate analysis involving 775 patients revealed that several factors including age,tumor differentiation,the American Joint Committee on Cancer(AJCC)T staging,N staging,and tumor node metastasis classification(TNM)stage significantly influenced overall survival(OS)and cancer-specific survival(CSS).Turning to the Zhongshan Hospital group(ZS group),which had 94 recruited patients,multivariate analysis for OS,CSS,and recurrence-free survival(RFS)showed that AJCC N staging emerged as the most significant risk factor,with hazard ratio(HR)values of 4.664,4.955,and 3.175,respectively.In subgroup analysis,ACT provided survival advantages for patients with positive lymph node metastasis(LNM).In a PSM analysis focused on patients with positive LNM,the comparison revealed that ACT emerged as a critical factor influencing both OS and CSS(both P<.005).Especially,these patients younger than 60 years old or those with AJCC-T2-N+staging were found to get apparently benefit from ACT as revealed by our subgroup interaction analysis.Conclusion:LNM plays a pivotal role in the management of invasive IPMN patients who underwent surgery,and ACT might be a beneficial therapeutic option for individuals concurrent with LNM,particularly among those younger than 60 years old,or with AJCC-T2-N+staging.
基金supported by the National Natural Science Foundation of China(No.21876124,U1732112,21790372,and 21822606)the Science Challenge Project(TZ2016004)the China Postdoctoral Science Foundation(2019M662062)。
文摘The extraction and complexation of trivalent Am(Ⅲ)and lanthanide(Ⅲ)with a new phenanthroline-derived phosphonate ligand,tetrabutyl-(1,10-phenanthrolin-2,9-diyl)phosphonate(C4-POPhen),were investigated by solvent extraction,absorption spectroscopy,NMR titration,luminescence spectroscopy,and theoretical computation.Selective extraction of Am(Ⅲ)over Eu(Ⅲ)from highly acidic HNO_(3) solution(up to 3.0 M)with good selectivity and a fast extraction rate was achieved by using the C4-POPhen ligand.The 1:2 metal/ligand complex was found to be the predominant species in the extracted organic phase by a slope analysis method.NMR titration results demonstrated that only a 1:1 complex of C4-POPhen with Ln(NO_(3))_(3) was formed in a CH_(3)OH system,while two complexes(1:1 and 1:2)were found when using Ln(ClO_(4))_(3) as the metal salts instead of Ln(NO_(3))3.The stability constants of the C4-POPhen/Am(Ⅲ)and C4-POPhen/Ln(Ⅲ)complexes in CH3OH with perchlorate and nitrate were determined by absorption spectroscopy.The Am(Ⅲ)complexes exhibited higher complexation ability than Ln(Ⅲ),which was consistent with the extraction results.DFT calculations also suggested that the Am–N bonds in C4-POPhen/Am(Ⅲ)complexes had a higher degree of covalence than the Eu–N bonds in C4-POPhen/Eu(Ⅲ)complexes,revealing the underlying driving force for the extraction selectivity of Am(Ⅲ)over Eu(Ⅲ)by C4-POPhen.These results indicate that phenanthroline-derived phosphate ligands may serve as promising candidates for separation of trivalent actinides over lanthanides from highly active nuclear waste.
基金supported by the U.S.Department of Energy Office of Science,Office of Basic Energy Sciences,Heavy Elements Chemistry Program at Colorado School of Mines under Award Number DE-SC0020189The Bk-249 and Cf-249 used in this and prior research by this PI were supplied by the United States Department of Energy Office of Science by the Isotope Program in the Office of Nuclear Physics+1 种基金The work at Tsinghua University was supported by Beijing Natural Science Foundation(Grant No.JQ20041)National Natural Science Foundation of China(Grant No.21822606).
文摘In the extraction of lanthanides by the sulfur donor ligand,Cyanex 301(HC301,bis(2,4,4-trimethylpentyl)dithiophosphinic acid),a transition in the coordination mode of extracted complexes has been observed between Eu and Gd.The light lanthanides La-Eu tend to be extracted as inner sphere complexes with HC301 directly coordinating the metal whereas the second half of the series Gd-Lu have a tendency to be extracted as outer sphere complexes.Without extended actinide studies,spanning the transplutonium actinides,it was unclear if a similar change in the extraction mechanism occurs in the actinide series.To assess this,solvent extraction studies were completed examining the slope dependence of the actinides and lathanides in the presence of varied nitrate and acid concentrations.Significant variation in the slope dependences was not observed for either the actinides or the lanthanides as pC_(H+)varied,however,the nitrate dependence and neodymium spectroscopy data suggest that the formation of outer sphere complexes is suppressed by higher nitrate concentrations.This suppression of outer sphere complexes enhanced the extraction of lanthanides,but not the actinides and suggests that the actinides form inner sphere complexes.Therefore,the HC301 separations chemistry observed thus far suggest differences in the chemistry of the actinides and lanthanides continues to persist deep into the actinide series.
文摘Pancreatic ductal adenocarcinoma is the known kind of tumor biologically featured as high malignant degree, lack of effective methods for diagnosis and treatment, which reflects its unpleasant prognosis. Recently, with the breakthrough of burgeoning therapeutic methods, the flush of dawn for pancreatic cancer nearly arrives. Nowadays, besides surgery, neoadjuvant chemoradiotherapy, tumor vaccine therapy, and immunotherapy all show their active situation and obtain certain clinical efficacy, but that is still limited to pancreatic cancer. However, the appearance and development of programmed cell death-1 (PD-1) immune checkpoint inhibitor may final improve survival of pancreatic cancer. This article aims to deeply understand the value of PD-1 immune checkpoint inhibitor in pancreatic cancer and validly provide the evidence for treatment by means of performing a systematic review on the current status in the fields of the mechanism and application of anti-PD-1 in pancreatic cancer, associations with surgery, PD- 1-related side effects and prospections.
