The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for ...The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology.In this study,the uniformity of the saturated calcareous sand treated with MICP was in-vestigated through one-dimensional calcareous sand column tests and model tests.The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate,cementation solution concentration,and number of injection cycles on the uniformity of the MICP treatment.Additionally,model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions.Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution,with a rate of 3 mL/min,yielding a favorable treatment effect.Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples.Conversely,excessively low concentrations may result in decreased bonding efficiency.Among the four considered con-centrations,0.5 mol/L and 1 mol/L exhibit superior reinforcing effects.The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution,exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part.Under three-dimensional seepage conditions,in addition to the non-uniform radial cementation along the injection pipe,there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects,resulting in preferential deposition of calcium carbonate at the lower section,The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom,thereby improving the reinforcement range and uniformity.展开更多
Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical b...Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.展开更多
Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because th...Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.展开更多
The complete catalytic oxidation of formaldehyde (HCHO) to CO_(2)and H_(2)O at room temperature is a green route for indoor HCHO removal.Zeolite is an excellent carrier material for HCHO oxidation due to its large sur...The complete catalytic oxidation of formaldehyde (HCHO) to CO_(2)and H_(2)O at room temperature is a green route for indoor HCHO removal.Zeolite is an excellent carrier material for HCHO oxidation due to its large surface area,intricate pores and high adsorption capacity.However,the zeolite-supported noble metal catalysts have currently shown relatively low activity especially at room temperature.In this work,we present a facile acid treatment strategy for zeolite catalysts to improve the hydroxyl concentration and further enhance their catalytic activity for HCHO oxidation.Activity tests illustrated that HCHO could be completely oxidized to CO_(2)and H_(2)O at a nearly 100%conversion rate with a weight hourly space velocity (WHSV) of 150,000 mL/(g·hr) at 25℃,when the support of Pd/USY catalysts was pretreated by hydrochloric acid with a concentration of 0.20 mol/L.The characterization results revealed that the active hydroxyl groups originated from the dealumination in the acid treatment play a key role in the HCHO oxidation reaction.The deduced reaction mechanism suggests that bridging hydroxyl groups may oxidize HCHO to dioxymethylene(DOM) species and terminal hydroxyl groups are responsible for the transformation of DOM groups to formate (HCOO) species.展开更多
Purpose: Prostate specific antigen levels can be normalized by the prostate volume to give a prostate specific antigen density (PSAd). Magnetic resonance imaging (MRI) can more accurately determine prostate zonal anat...Purpose: Prostate specific antigen levels can be normalized by the prostate volume to give a prostate specific antigen density (PSAd). Magnetic resonance imaging (MRI) can more accurately determine prostate zonal anatomy and prostate volumes compared to transrectal ultrasound, and hence may lead to more accurate PSAd measurements. Methods: Imaging and pathology of men undergoing prostate MRI from April 2007 to May 2009 were reviewed in this retrospective study. 73 patients were included for analysis, of which 45 had prostate cancer and 28 did not have cancer. Total, transitional zone, and peripheral zone values were determined by ultrasound prolate ellipse, MRI prolate ellipse, and MRI segmentation methods. Results: The study population showed an average PSA of 6.3 ng/mL, with the control mean PSA (8.8 ng/mL) being greater than the cancer group (5.3 ng/mL). Transrectal ultrasound underestimated the prostate volume (mean 27.7 mL versus MRI volume of 38.3 mL, p ≤ 0.001). No difference was seen between cancer and control populations using PSAd. PSAd correctly categorized low (Gleason < 7) and high-grade cancers (Gleason ≥ 7) in patients with malignancy. Conclusion: Transrectal ultrasound underestimates prostate volumes and hence is inaccurate in calculating PSAd. MRI more accurately depicts PSAd, however PSAd is unable to differentiate between patients with cancer and benign disease such as BPH or prostatitis.展开更多
Calcareous sand is the main fill material for island reclamation projects,but untreated calcareous sand might not be used as a reclamation fill due to its poor mechanical properties.Microbial induced calcite precipita...Calcareous sand is the main fill material for island reclamation projects,but untreated calcareous sand might not be used as a reclamation fill due to its poor mechanical properties.Microbial induced calcite precipitation(MICP)was directly used to consolidate calcareous sands.One-dimensional sand column tests were conducted to identify the optimized solutions and to investigate the effects of cement solution concentration,relative density,and consolidation frequencies on the permeability and mechanical properties of MICP-treated calcareous sands.Finally,three-dimensional model tests were carried out to investigate the effective consolidation range of microbially treated calcareous sands.The results show that the MICP-treated calcareous sand shows a reduction in the permeability of the sample,while the calcium carbonate cementation and its filling effect improves the mechanical properties of the soil.The one-dimentional test results show that the effective values for cement solution concentration,relative density,and consolidation frequencies range from 0.5 mol/L to 1.5 mol/L,30%-70%,and 5-15 times.The consolidation frequencies have the greatest influence on the permeability and strength properties of the treated calcareous sand.A quadratic polynomial regression model for permeability and strength was established through response surface analysis,and the regression model proved to be highly accurate and reliable through testing.In three-dimentional tests,the consolidation range tends to move downwards in a trapezoidal shape,showing a"big bottom and small top"pattern,with a consolidation range of approximately 34 times the diameter of the pipe.This study serves as a reference for selecting consolidation parameters for subsequent tests and applications of MICP-treated calcareous sands.展开更多
The four-dimensional variational assimilation(4D-Var)has been widely used in meteorological and oceanographic data assimilation.This method is usually implemented in the model space,known as primal approach(P4D-Var).A...The four-dimensional variational assimilation(4D-Var)has been widely used in meteorological and oceanographic data assimilation.This method is usually implemented in the model space,known as primal approach(P4D-Var).Alternatively,physical space analysis system(4D-PSAS)is proposed to reduce the computation cost,in which the 4D-Var problem is solved in physical space(i.e.,observation space).In this study,the conjugate gradient(CG)algorithm,implemented in the 4D-PSAS system is evaluated and it is found that the non-monotonic change of the gradient norm of 4D-PSAS cost function causes artificial oscillations of cost function in the iteration process.The reason of non-monotonic variation of gradient norm in 4D-PSAS is then analyzed.In order to overcome the non-monotonic variation of gradient norm,a new algorithm,Minimum Residual(MINRES)algorithm,is implemented in the process of assimilation iteration in this study.Our experimental results show that the improved 4D-PSAS with the MINRES algorithm guarantees the monotonic reduction of gradient norm of cost function,greatly improves the convergence properties of 4D-PSAS as well,and significantly restrains the numerical noises associated with the traditional 4D-PSAS system.展开更多
A highly sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the de-termination of imperatorin and isoimperatorin in rat plasma using psoralen as internal standard. Analyses w...A highly sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the de-termination of imperatorin and isoimperatorin in rat plasma using psoralen as internal standard. Analyses were performed on a Shimadzu HPLC system using a Shimadzu C18 column eluted with a mobile phase of methanol-water (25:75), containing 0.1% formic acid at a flow rate of 0.4 ml/min. The detection was performed by positive ion elec-trospray ionization in multiple reactions monitoring mode, monitoring the transitions m/z 203→147 and m/z 203→159 for imperatorin and isoimperatorin, respectively. The method was validated over the concentration range of 2.5 -1000.0 ng/mL for imperatorin and isoimperatorin. The limits of detection and quantification were 1.0 and 3.0 ng/mL, repectively for both analytes. The intra-day and inter-day accuracy and precision of the assay were less than 10.9%. This method has been applied successfully to a pharmacokinetic study involving the intragastric administration of extract of Angelicae Dahuricae Radix to rats.展开更多
Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify pr...Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify prolyl 3-hydroxylase family member 4(P3H4)as a critical mediator of extracellular matrix(ECM)remodeling,epithelial-mesenchymal transition(EMT),and the exclusion of cytotoxic CD8+T lymphocytes.Elevated P3H4 expression correlates with unfavorable clinical outcomes and resistance to immunotherapy.Genetic ablation of P3H4 significantly attenuates tumor progression and promotes CD8^(+)T cell infiltration.To pharmacologically target P3H4,we engineered a liposomal formulation of 1,4-dihydrophenanthroline-2,5-dicarboxylic acid(1,4-DPCA),a small-molecule prolyl hydroxylase inhibitor.This nanomedicine,designated Lipo-1,4-DPCA,effectively downregulates P3H4 expression,mitigates tumor-associated fibrosis,reprograms the immune microenvironment,and elicits robust anti-tumor responses in vivo.Collectively,our findings establish P3H4 as a promising therapeutic target and highlight Lipo-1,4-DPCA as a dualfunctional nanotherapeutic candidate capable of enhancing the efficacy of immunotherapy in OSCC.展开更多
A biomimetic electrical microenvironment is known to facilitate bone defect repair.Nevertheless,precise and non-invasive modulation of the in situ electrical microenvironment poses a formidable challenge.This study de...A biomimetic electrical microenvironment is known to facilitate bone defect repair.Nevertheless,precise and non-invasive modulation of the in situ electrical microenvironment poses a formidable challenge.This study develops a poly(vinylidene fluoride-trifluoroethylene)(P(VDF-TrFE))membrane with a precisely controlled porous structure.Ultrasonic stimulation is applied to induce acoustic-mechanic-electric(AcME)conversion and regulate the membrane’s surface potential to modulate the in situ electrical microenvironment.When the ultrasound frequency aligns with the membrane’s inherent frequency,maximal electrical energy conversion occurs via the resonance effect,which generates the highest possible surface potential.The maximal AcME conversion is achieved by a 12μm pore-sized P(VDF-TrFE)membrane with a resonance frequency of 40 kHz,resulting in the highest surface potential of-65.56 mV.Finite element modeling indicates that the deformation and stress of porous membranes are higher than that of non-porous membranes under the stimulation of ultrasound,yielding the highest surface potential.In vitro experiments and sequencing analysis show that the honeycomb sandwich-structured P(VDF-TrFE)membrane under the stimulation of the resonance ultrasound promoted osteogenic differentiation of rBMSCs through the PI3K-Akt signaling pathway.When the porous membranes are implanted to cover cranial defects,the bone defect repair is significantly enhanced under the stimulation of ultrasound compared with the non-porous membranes.This study establishes a new strategy for efficient AcME conversion on piezoelectric membranes and offers new insights into the applications of ultrasound-responsive piezoelectric materials for bone defect repair.展开更多
Numerous news or event pictures are taken and shared on the internet every day that have abundant information worth being mined,but only a small fraction of them are geotagged.The visual content of the news image hint...Numerous news or event pictures are taken and shared on the internet every day that have abundant information worth being mined,but only a small fraction of them are geotagged.The visual content of the news image hints at clues of the geographical location because they are usually taken at the site of the incident,which provides a prerequisite for geo-localization.This paper proposes an automated pipeline based on deep learning for the geo-localization of news pictures in a large-scale urban environment using geotagged street view images as a reference dataset.The approach obtains location information by constructing an attention-based feature extraction network.Then,the image features are aggregated,and the candidate street view image results are retrieved by the selective matching kernel function.Finally,the coordinates of the news images are estimated by the kernel density prediction method.The pipeline is tested in the news pictures in Hong Kong.In the comparison experiments,the proposed pipeline shows stable performance and generalizability in the large-scale urban environment.In addition,the performance analysis of components in the pipeline shows the ability to recognize localization features of partial areas in pictures and the effectiveness of the proposed solution in news picture geo-localization.展开更多
The precise control of the conformations of biomolecules adsorbed on a surface at the single-molecule level is significant. However, it remains a huge challenge because of the complex structure and conformation divers...The precise control of the conformations of biomolecules adsorbed on a surface at the single-molecule level is significant. However, it remains a huge challenge because of the complex structure and conformation diversity of biomolecules. Herein, a ＂nanopore-confined recognition＂ strategy is proposed to manipulate the adsorption of individual valinomycin molecules at room temperature through precise design of functionalized conjugated macrocycle （CPN8） supramolecular nanopores with complementary architectures and binding sites. We revealed that CPN8 prefers to selectively recognizing valinomycin with complementary architecture because of the strong synergistic interactions between the isopropyl groups of valinomycin and the amino groups of CPN8, with valinomycin- highly oriented pyrolytic graphite （HOPG） interactions. Our perspectives at the single-molecule level will provide valuable insights to improve the design of supramolecular nanopores for conformation-selective recognition of non-conjugated molecules.展开更多
高性能电极材料开发是大电流密度电解水制氢的关键.实验采用微波等离子体化学气相沉积(MPCVD)实现Mo基体直接生长活性MoS_(2)纳米片阵列,设计CH4/H2等离子体实现碳掺杂原位调控活性层MoS_(2)晶相结构,制备了呈异质结构的1T/2H-MoS_(2)@M...高性能电极材料开发是大电流密度电解水制氢的关键.实验采用微波等离子体化学气相沉积(MPCVD)实现Mo基体直接生长活性MoS_(2)纳米片阵列,设计CH4/H2等离子体实现碳掺杂原位调控活性层MoS_(2)晶相结构,制备了呈异质结构的1T/2H-MoS_(2)@Mo电极.电化学性能测试显示,1T/2H-MoS_(2)@Mo电极在1000 mA cm^(-2)大电流密度下表现出281 mV低过电位和超100 h的持续稳定性.Butler-Volmer(B-V)拟合证实,1T/2H-MoS_(2)@Mo具有媲美Pt的动力学性能.密度泛函理论(DFT)计算表明,C掺杂诱导形成的1T/2H-MoS_(2)晶体畴壁具有非对称性结构,造成MoS_(2)表面电荷的不均匀分布,进而激活表面惰性S位点,降低氢吸附自由能(ΔGH*);同时,Mo基体与活性层1T/2H-MoS_(2)间的能带重叠效应,赋予1T/2H-MoS_(2)@Mo优异的载体/活性层界面结构稳定性.MPCVD自生长晶相结构调控策略为大电流密度非贵金属析氢电极制备提供了技术支持.展开更多
基金support of Natural Science Foundation of China(Grant No.52108324,No.52008207,and No.52108298)for conducting this study.
文摘The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology.In this study,the uniformity of the saturated calcareous sand treated with MICP was in-vestigated through one-dimensional calcareous sand column tests and model tests.The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate,cementation solution concentration,and number of injection cycles on the uniformity of the MICP treatment.Additionally,model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions.Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution,with a rate of 3 mL/min,yielding a favorable treatment effect.Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples.Conversely,excessively low concentrations may result in decreased bonding efficiency.Among the four considered con-centrations,0.5 mol/L and 1 mol/L exhibit superior reinforcing effects.The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution,exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part.Under three-dimensional seepage conditions,in addition to the non-uniform radial cementation along the injection pipe,there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects,resulting in preferential deposition of calcium carbonate at the lower section,The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom,thereby improving the reinforcement range and uniformity.
基金financially supported by the National Natural Science Foundation of China(Nos.22272118,22172111 and 22309134)the Science and Technology Commission of Shanghai Municipality,China(Nos.22ZR1464100,20ZR1460300 and 19DZ2271500)+3 种基金China Postdoctoral Science Foundation(2022M712402)Shanghai Rising-Star Program(23YF1449200)Zhejiang Provincial Science and Technology Project(2022C01182)the Fundamental Research Funds for the Central Universities(22120210529 and 2023-3-YB-07)。
文摘Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.
文摘Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.
基金supported by the Central government guides local funds for science and technology development (No. 2020L3023)the NSF of Fujian Province (No. 2018J01024), Youth Innovation Promotion Association, Chinese Academy of Sciences (CAS) (No. 2020310)+1 种基金the Fujian Institute of Research on the Structure of Matter and Institute of Urban Environment (FJIRSM&IUE) Joint Research Fund (No. RHZX-2019-001)the Science and Technology Planning Project of Xiamen City (No. 3502Z20191021)。
文摘The complete catalytic oxidation of formaldehyde (HCHO) to CO_(2)and H_(2)O at room temperature is a green route for indoor HCHO removal.Zeolite is an excellent carrier material for HCHO oxidation due to its large surface area,intricate pores and high adsorption capacity.However,the zeolite-supported noble metal catalysts have currently shown relatively low activity especially at room temperature.In this work,we present a facile acid treatment strategy for zeolite catalysts to improve the hydroxyl concentration and further enhance their catalytic activity for HCHO oxidation.Activity tests illustrated that HCHO could be completely oxidized to CO_(2)and H_(2)O at a nearly 100%conversion rate with a weight hourly space velocity (WHSV) of 150,000 mL/(g·hr) at 25℃,when the support of Pd/USY catalysts was pretreated by hydrochloric acid with a concentration of 0.20 mol/L.The characterization results revealed that the active hydroxyl groups originated from the dealumination in the acid treatment play a key role in the HCHO oxidation reaction.The deduced reaction mechanism suggests that bridging hydroxyl groups may oxidize HCHO to dioxymethylene(DOM) species and terminal hydroxyl groups are responsible for the transformation of DOM groups to formate (HCOO) species.
文摘Purpose: Prostate specific antigen levels can be normalized by the prostate volume to give a prostate specific antigen density (PSAd). Magnetic resonance imaging (MRI) can more accurately determine prostate zonal anatomy and prostate volumes compared to transrectal ultrasound, and hence may lead to more accurate PSAd measurements. Methods: Imaging and pathology of men undergoing prostate MRI from April 2007 to May 2009 were reviewed in this retrospective study. 73 patients were included for analysis, of which 45 had prostate cancer and 28 did not have cancer. Total, transitional zone, and peripheral zone values were determined by ultrasound prolate ellipse, MRI prolate ellipse, and MRI segmentation methods. Results: The study population showed an average PSA of 6.3 ng/mL, with the control mean PSA (8.8 ng/mL) being greater than the cancer group (5.3 ng/mL). Transrectal ultrasound underestimated the prostate volume (mean 27.7 mL versus MRI volume of 38.3 mL, p ≤ 0.001). No difference was seen between cancer and control populations using PSAd. PSAd correctly categorized low (Gleason < 7) and high-grade cancers (Gleason ≥ 7) in patients with malignancy. Conclusion: Transrectal ultrasound underestimates prostate volumes and hence is inaccurate in calculating PSAd. MRI more accurately depicts PSAd, however PSAd is unable to differentiate between patients with cancer and benign disease such as BPH or prostatitis.
基金supported by the National Natural Science Foundation of China(Grant No.51879090 and Grant No.52179101).
文摘Calcareous sand is the main fill material for island reclamation projects,but untreated calcareous sand might not be used as a reclamation fill due to its poor mechanical properties.Microbial induced calcite precipitation(MICP)was directly used to consolidate calcareous sands.One-dimensional sand column tests were conducted to identify the optimized solutions and to investigate the effects of cement solution concentration,relative density,and consolidation frequencies on the permeability and mechanical properties of MICP-treated calcareous sands.Finally,three-dimensional model tests were carried out to investigate the effective consolidation range of microbially treated calcareous sands.The results show that the MICP-treated calcareous sand shows a reduction in the permeability of the sample,while the calcium carbonate cementation and its filling effect improves the mechanical properties of the soil.The one-dimentional test results show that the effective values for cement solution concentration,relative density,and consolidation frequencies range from 0.5 mol/L to 1.5 mol/L,30%-70%,and 5-15 times.The consolidation frequencies have the greatest influence on the permeability and strength properties of the treated calcareous sand.A quadratic polynomial regression model for permeability and strength was established through response surface analysis,and the regression model proved to be highly accurate and reliable through testing.In three-dimentional tests,the consolidation range tends to move downwards in a trapezoidal shape,showing a"big bottom and small top"pattern,with a consolidation range of approximately 34 times the diameter of the pipe.This study serves as a reference for selecting consolidation parameters for subsequent tests and applications of MICP-treated calcareous sands.
基金The National Key Research and Development Program of China under contract Nos 2017YFC1501803 and2018YFC1506903the National Natural Science Foundation of China under contract Nos 91730304,41475021 and 41575026
文摘The four-dimensional variational assimilation(4D-Var)has been widely used in meteorological and oceanographic data assimilation.This method is usually implemented in the model space,known as primal approach(P4D-Var).Alternatively,physical space analysis system(4D-PSAS)is proposed to reduce the computation cost,in which the 4D-Var problem is solved in physical space(i.e.,observation space).In this study,the conjugate gradient(CG)algorithm,implemented in the 4D-PSAS system is evaluated and it is found that the non-monotonic change of the gradient norm of 4D-PSAS cost function causes artificial oscillations of cost function in the iteration process.The reason of non-monotonic variation of gradient norm in 4D-PSAS is then analyzed.In order to overcome the non-monotonic variation of gradient norm,a new algorithm,Minimum Residual(MINRES)algorithm,is implemented in the process of assimilation iteration in this study.Our experimental results show that the improved 4D-PSAS with the MINRES algorithm guarantees the monotonic reduction of gradient norm of cost function,greatly improves the convergence properties of 4D-PSAS as well,and significantly restrains the numerical noises associated with the traditional 4D-PSAS system.
文摘A highly sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the de-termination of imperatorin and isoimperatorin in rat plasma using psoralen as internal standard. Analyses were performed on a Shimadzu HPLC system using a Shimadzu C18 column eluted with a mobile phase of methanol-water (25:75), containing 0.1% formic acid at a flow rate of 0.4 ml/min. The detection was performed by positive ion elec-trospray ionization in multiple reactions monitoring mode, monitoring the transitions m/z 203→147 and m/z 203→159 for imperatorin and isoimperatorin, respectively. The method was validated over the concentration range of 2.5 -1000.0 ng/mL for imperatorin and isoimperatorin. The limits of detection and quantification were 1.0 and 3.0 ng/mL, repectively for both analytes. The intra-day and inter-day accuracy and precision of the assay were less than 10.9%. This method has been applied successfully to a pharmacokinetic study involving the intragastric administration of extract of Angelicae Dahuricae Radix to rats.
基金supported by grants from the National Natural Science Foundation of China(Nos.82501207,81700993,52403312,and 82571151)Postdoctoral Fellowship Program of CPSF(No.GZC20251219)+1 种基金the Beijing Nova Program(No.20250484855)the Beijing Natural Science Foundation(No.L252168).
文摘Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify prolyl 3-hydroxylase family member 4(P3H4)as a critical mediator of extracellular matrix(ECM)remodeling,epithelial-mesenchymal transition(EMT),and the exclusion of cytotoxic CD8+T lymphocytes.Elevated P3H4 expression correlates with unfavorable clinical outcomes and resistance to immunotherapy.Genetic ablation of P3H4 significantly attenuates tumor progression and promotes CD8^(+)T cell infiltration.To pharmacologically target P3H4,we engineered a liposomal formulation of 1,4-dihydrophenanthroline-2,5-dicarboxylic acid(1,4-DPCA),a small-molecule prolyl hydroxylase inhibitor.This nanomedicine,designated Lipo-1,4-DPCA,effectively downregulates P3H4 expression,mitigates tumor-associated fibrosis,reprograms the immune microenvironment,and elicits robust anti-tumor responses in vivo.Collectively,our findings establish P3H4 as a promising therapeutic target and highlight Lipo-1,4-DPCA as a dualfunctional nanotherapeutic candidate capable of enhancing the efficacy of immunotherapy in OSCC.
基金supported by the National Natural Science Foundation of China(Nos.82471029,U22A20314,and 81600905)the Peking University Medicine Fund of Fostering Young Scholars’Scentific&Technological Innovation supported by the Fundamental Research Funds for the Central Universities(No.BMU2018PY005)the National Key Research and Development Program of China(No.2018YFE0194400).
文摘A biomimetic electrical microenvironment is known to facilitate bone defect repair.Nevertheless,precise and non-invasive modulation of the in situ electrical microenvironment poses a formidable challenge.This study develops a poly(vinylidene fluoride-trifluoroethylene)(P(VDF-TrFE))membrane with a precisely controlled porous structure.Ultrasonic stimulation is applied to induce acoustic-mechanic-electric(AcME)conversion and regulate the membrane’s surface potential to modulate the in situ electrical microenvironment.When the ultrasound frequency aligns with the membrane’s inherent frequency,maximal electrical energy conversion occurs via the resonance effect,which generates the highest possible surface potential.The maximal AcME conversion is achieved by a 12μm pore-sized P(VDF-TrFE)membrane with a resonance frequency of 40 kHz,resulting in the highest surface potential of-65.56 mV.Finite element modeling indicates that the deformation and stress of porous membranes are higher than that of non-porous membranes under the stimulation of ultrasound,yielding the highest surface potential.In vitro experiments and sequencing analysis show that the honeycomb sandwich-structured P(VDF-TrFE)membrane under the stimulation of the resonance ultrasound promoted osteogenic differentiation of rBMSCs through the PI3K-Akt signaling pathway.When the porous membranes are implanted to cover cranial defects,the bone defect repair is significantly enhanced under the stimulation of ultrasound compared with the non-porous membranes.This study establishes a new strategy for efficient AcME conversion on piezoelectric membranes and offers new insights into the applications of ultrasound-responsive piezoelectric materials for bone defect repair.
文摘Numerous news or event pictures are taken and shared on the internet every day that have abundant information worth being mined,but only a small fraction of them are geotagged.The visual content of the news image hints at clues of the geographical location because they are usually taken at the site of the incident,which provides a prerequisite for geo-localization.This paper proposes an automated pipeline based on deep learning for the geo-localization of news pictures in a large-scale urban environment using geotagged street view images as a reference dataset.The approach obtains location information by constructing an attention-based feature extraction network.Then,the image features are aggregated,and the candidate street view image results are retrieved by the selective matching kernel function.Finally,the coordinates of the news images are estimated by the kernel density prediction method.The pipeline is tested in the news pictures in Hong Kong.In the comparison experiments,the proposed pipeline shows stable performance and generalizability in the large-scale urban environment.In addition,the performance analysis of components in the pipeline shows the ability to recognize localization features of partial areas in pictures and the effectiveness of the proposed solution in news picture geo-localization.
基金Acknowledgements The authors gratefully acknowledged Prof. Chen Wang （National Center for Nanoscience and Technology, China） and Prof. Guocong Guo （Fujian Institute of Research on the Structure of Matter, CAS） for their helpful discussions and advice. This work was supported by the National Basic Research Program of China （No. 2012CB933001）, the National Natural Science Foundation of China （Nos. 51173031, 21472029, 21303202, and 91127043）, the program of Chinese Academy of Sciences （No. YZ201318）, and the Open Project of State Key Laboratory of Supramolecular Structure and Materials （No. sklssm201607）.
文摘The precise control of the conformations of biomolecules adsorbed on a surface at the single-molecule level is significant. However, it remains a huge challenge because of the complex structure and conformation diversity of biomolecules. Herein, a ＂nanopore-confined recognition＂ strategy is proposed to manipulate the adsorption of individual valinomycin molecules at room temperature through precise design of functionalized conjugated macrocycle （CPN8） supramolecular nanopores with complementary architectures and binding sites. We revealed that CPN8 prefers to selectively recognizing valinomycin with complementary architecture because of the strong synergistic interactions between the isopropyl groups of valinomycin and the amino groups of CPN8, with valinomycin- highly oriented pyrolytic graphite （HOPG） interactions. Our perspectives at the single-molecule level will provide valuable insights to improve the design of supramolecular nanopores for conformation-selective recognition of non-conjugated molecules.
文摘高性能电极材料开发是大电流密度电解水制氢的关键.实验采用微波等离子体化学气相沉积(MPCVD)实现Mo基体直接生长活性MoS_(2)纳米片阵列,设计CH4/H2等离子体实现碳掺杂原位调控活性层MoS_(2)晶相结构,制备了呈异质结构的1T/2H-MoS_(2)@Mo电极.电化学性能测试显示,1T/2H-MoS_(2)@Mo电极在1000 mA cm^(-2)大电流密度下表现出281 mV低过电位和超100 h的持续稳定性.Butler-Volmer(B-V)拟合证实,1T/2H-MoS_(2)@Mo具有媲美Pt的动力学性能.密度泛函理论(DFT)计算表明,C掺杂诱导形成的1T/2H-MoS_(2)晶体畴壁具有非对称性结构,造成MoS_(2)表面电荷的不均匀分布,进而激活表面惰性S位点,降低氢吸附自由能(ΔGH*);同时,Mo基体与活性层1T/2H-MoS_(2)间的能带重叠效应,赋予1T/2H-MoS_(2)@Mo优异的载体/活性层界面结构稳定性.MPCVD自生长晶相结构调控策略为大电流密度非贵金属析氢电极制备提供了技术支持.
