We present our experiment on magnetic field induced spectroscopy of the ^(1)S0–^(3)P0 transition of ^(88)Sr atoms with a 10 Hz linewidth laser.The ^(88)Sr atoms are cooled by two stage laser cooling.After the second ...We present our experiment on magnetic field induced spectroscopy of the ^(1)S0–^(3)P0 transition of ^(88)Sr atoms with a 10 Hz linewidth laser.The ^(88)Sr atoms are cooled by two stage laser cooling.After the second stage narrow line laser cooling,the temperature of the atoms is reduced to~3μK.The atoms are then loaded into an 813 nm one-dimensional optical lattice.A homemade 698 nm laser with 10 Hz linewidth and maximum intensity of more than 100 W/cm2 is used to probe the ^(88)Sr atoms in the lattice.By means of a magnetic field of~1 mT and a probe laser with 50 ms pulse and~6 W/cm^(2) intensity,the Doppler free ^(88)Sr ^(1)S0–^(3)P0 transition spectrum with a linewidth of 208 Hz is obtained.展开更多
Recently,magnetism in two-dimensional(2 D)van der Waals(vd W)materials has attracted wide interests.It is anticipated that these materials will stimulate discovery of new physical phenomena and novel applications.The ...Recently,magnetism in two-dimensional(2 D)van der Waals(vd W)materials has attracted wide interests.It is anticipated that these materials will stimulate discovery of new physical phenomena and novel applications.The capability to quantitatively measure the magnetism of 2 D magnetic vd W materials is essential to understand these materials.Here we report on quantitative measurements of ferromagnetic-to-paramagnetic phase transition of an atomically thin(down to 11 nm)vd W magnet,namely Cr Br_(3),with a Curie point of 37.5 K.This experiment demonstrates that surface magnetism can be quantitatively investigated,which is useful for a wide variety of potential applications.展开更多
A central research topic in condensed matter physics is the understanding of the evolution of various phases and phase transitions under different tuning parameters such as temperature, magnetic field and pressure. To...A central research topic in condensed matter physics is the understanding of the evolution of various phases and phase transitions under different tuning parameters such as temperature, magnetic field and pressure. To explore the pressure-induced evolution of the magnetism and Fermi surface of the heavy fermion antiferromagnet Yb Pt Bi, we performed tunnel diode oscillator based measurements under pressure at low temperatures in high magnetic fields. Our results reveal that the magnetic order strengthens and the Fermi surface shrinks as the pressure increases, which are consistent with typical observations for Yb-based heavy fermion compounds. In addition, an anomalous change in the quantum oscillation amplitudes is observed above 1.5 GPa, and determining the origin requires further study.展开更多
The nucleon spatial density distribution is of critical importance for atomic nucleus structure.The nuclei with central density depletions,usually called bubble nuclei,has been studied for more than 70 years.Based on ...The nucleon spatial density distribution is of critical importance for atomic nucleus structure.The nuclei with central density depletions,usually called bubble nuclei,has been studied for more than 70 years.Based on the isospin-dependent Boltzmann-Uehling-Uhlenbeck transport model.展开更多
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa...Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications.展开更多
A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phospho...A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.展开更多
To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparat...To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparative analysis of the probe's performance in various buffer systems revealed that buffers with high organic content are unsuitable for evaluating such probes.Furthermore,the pH of the solvent system was found to significantly influence the probe's behavior.Under highly acidic conditions(pH≤2),DHU‑NP‑4 exhibited exceptional specificity for Fe^(3+),while in alkaline conditions,it demonstrated high specificity for Cu^(2+).Leveraging these properties,the probe enabled the quantitative detection of Fe^(3+)and Cu^(2+)in solution.展开更多
The presence of aluminum(Al^(3+))and fluoride(F^(−))ions in the environment can be harmful to ecosystems and human health,highlighting the need for accurate and efficient monitoring.In this paper,an innovative approac...The presence of aluminum(Al^(3+))and fluoride(F^(−))ions in the environment can be harmful to ecosystems and human health,highlighting the need for accurate and efficient monitoring.In this paper,an innovative approach is presented that leverages the power of machine learning to enhance the accuracy and efficiency of fluorescence-based detection for sequential quantitative analysis of aluminum(Al^(3+))and fluoride(F^(−))ions in aqueous solutions.The proposed method involves the synthesis of sulfur-functionalized carbon dots(C-dots)as fluorescence probes,with fluorescence enhancement upon interaction with Al^(3+)ions,achieving a detection limit of 4.2 nmol/L.Subsequently,in the presence of F^(−)ions,fluorescence is quenched,with a detection limit of 47.6 nmol/L.The fingerprints of fluorescence images are extracted using a cross-platform computer vision library in Python,followed by data preprocessing.Subsequently,the fingerprint data is subjected to cluster analysis using the K-means model from machine learning,and the average Silhouette Coefficient indicates excellent model performance.Finally,a regression analysis based on the principal component analysis method is employed to achieve more precise quantitative analysis of aluminum and fluoride ions.The results demonstrate that the developed model excels in terms of accuracy and sensitivity.This groundbreaking model not only showcases exceptional performance but also addresses the urgent need for effective environmental monitoring and risk assessment,making it a valuable tool for safeguarding our ecosystems and public health.展开更多
Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a seri...Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a serious threat to the long-term survival rate of the CRC patients.Recent studies have shown that relative higher viscosity was presented in tumor cells compared to that in normal cells,leading to viscosity as a potential biomarker for CRC.Herein,we reported the development of a series of novel viscosity-sensitive and mitochondria-specific fluorescent probes(HTB,HTI,and HTP)for CRC detection.Among them,HTB showed high sensitivity,minimal background interference,low cytotoxicity,and significant viscous response capability,making it an ideal tool for distinguishing colorectal tumor cells from normal cells.Importantly,we have successfully utilized HTB to visualize in a CRC-cells-derived xenograft(CDX)model,enriching its medical imaging capacity,which laid a foundation for further clinical translational application.展开更多
Tetracycline(TC)is a broad-spectrum antibiotic,and its residues in the environment and food are harmful to human health.Therefore,it is essential to rapidly,sensitively,and conveniently detect TC.In this work,we devel...Tetracycline(TC)is a broad-spectrum antibiotic,and its residues in the environment and food are harmful to human health.Therefore,it is essential to rapidly,sensitively,and conveniently detect TC.In this work,we developed a portable silicon nanoparticles chelated Europium(Ⅲ)-based polyacrylonitrile(Eu-SiNPs/PAN)nanofiber membrane for rapid,sensitive,and convenient detection of TC.The Eu-SiNPs were synthesized with a facile one-pot method.The Eu-SiNPs/PAN nanofiber membrane was fabricated by electrospinning,combining Eu-SiNPs and PAN with three-dimensional porous membrane structures and UV resistance.Both the Eu-SiNPs and the Eu-SiNPs/PAN nanofiber membranes have good selectivity and anti-interference ability towards TC.The combined merits of rapid response,long storage life,easy portability,and naked-eye recognition of TC make the Eu-SiNPs/PAN nanofiber membrane a promising material for convenient TC detection applications.The practicability of these nanofiber membranes was further verified by detecting TC in real samples,such as lake water,drinking water and honey,and achieved quantitative detection.展开更多
Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint def...Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint deformity and dysfunction in severe cases.The pathologic development of RA involves complex interactions of multiple biomarkers,and detecting a single biomarker may produce falsepositive results due to other confounding factors.Therefore,fluorescent probes that can detect multiple biomarkers simultaneously are crucial for precise RA diagnosis.Peroxynitrite(ONOO^(-)) and viscosity are inflammation-related factors in cells.In this study,we developed a dual responsive near-infrared fluorescent probe,YLS,for ONOO^(-) and viscosity.The probe features dual-channel turn-on fluorescence responses at 625 and 760 nm upon the presence of ONOO^(-) and viscosity,respectively.Supported by YLS,we found that during RA pathology,lymphocyte infiltration not only increases the concentration of proteins in the joint fluid resulting in elevated viscosity;at the same time,the overproduction of ONOO^(-) exacerbates oxidative stress and inflammatory responses.This multiparameter assay is expected to improve the diagnostic accuracy of the early stages of RA,thus providing a scientific basis for early intervention and personalized treatment.展开更多
Inductive-pulsed plasma thruster is an in-space propulsion device that generates thrust by ionizing and accelerating plasma through pulsed electromagnetic field.In this paper,the correlation between plasma structure e...Inductive-pulsed plasma thruster is an in-space propulsion device that generates thrust by ionizing and accelerating plasma through pulsed electromagnetic field.In this paper,the correlation between plasma structure evolution and magnetic field permeability is studied using a B-dot probe array system,combing with high-speed camera and electrical parameter measurement.Further discussions explained the mechanism how the magnetic permeation characteristics affect the energy deposition between circuit and plasma.展开更多
In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission sp...In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission spectrum range:640-740 nm)and coumarin fluorophore(emission spectrum range:440-600 nm)as signal output units,thereby achieving effective spectral separation and highly selective detection of HClO.Under physiological pH conditions,HClO triggers an oxidation-cleavage reaction,releasing methylene blue and coumarin,which emit distinct red and green fluorescence,respectively.This dual-emission feature enabled rapid HClO detection with two-channel detection limits of 25.13 nmol·L^(-1)(green channel)and 31.55 nmol·L^(-1)(red channel).Furthermore,in cell imaging experiments,this probe demonstrated excellent cell membrane permeability and low cytotoxicity,successfully enabling the monitoring of both endogenous and exogenous HClO in living cells.By incorporating a twochannel self-calibration system,the probe effectively mitigated signal variations caused by instrumental or environmental interference,substantially improving detection sensitivity and reliability.展开更多
This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwel...This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwellian and triple-Maxwellian Electron Energy Distribution Function(EEDF)plasmas.Discus⁃sion and demonstration of procedures include the treatment of the ion saturation current,electron saturation cur⁃rent,space-charge effects on the I-V trace,and most importantly how to properly isolate and fit for each electron group present in an I-V trace reflecting a mult-Maxwellian EEDF,as well as how having a multi-Maxwellian EEDF affects the procedures of treating the ion and electron saturation currents.Shortcomings of common improp⁃er procedures are discussed and demonstrated with simulated I-V traces to show how these procedures gives false measurements.展开更多
Herein,a one-pot chemical reduction method was reported to prepare folic acid(FA)-stabilized silver nanoclusters(FA@Ag NCs),in which FA,hydrazine hydrate,and silver nitrate were used as capping agent,reducing agent,an...Herein,a one-pot chemical reduction method was reported to prepare folic acid(FA)-stabilized silver nanoclusters(FA@Ag NCs),in which FA,hydrazine hydrate,and silver nitrate were used as capping agent,reducing agent,and precursor,respectively.Several technologies were employed to investigate the structures and optical properties of FA@Ag NCs,including transmission electron microscopy(TEM),X-ray photoelectron spectrometer(XPS),Fourier transform infrared spectrometer(FTIR),X-ray diffractometer(XRD),fluorescence spectrometer,and ultraviolet visible absorption spectrometer.FA@Ag NCs were suggested to be highly dispersed and spherical with a size of around 2.8 nm.Moreover,the maximum excitation and emission wavelengths of FA@Ag NCs were 370 and 447 nm,respectively.Under the optimal detection conditions,FA@Ag NCs could be used to effectively detect malachite green with the linear detection range of 0.5-200μmol·L^(-1).The detection limit was 0.084μmol·L^(-1).The fluorescence-quenching mechanism was ascribed to the static quenching.The detection system based on FA@AgNCs was successfully used for the detection of malachite green in actual samples with good accuracy and reproducibility.展开更多
The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic s...The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.展开更多
Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed...Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed for the dual-functional detection of environmental pollutants.This fluorescence-quenching-based sensor exhibited excep-tional sensitivity for both 2,4,6-trinitrophenol(TNP)and tetracycline(TC),achieving remarkably low detection lim-its of 1.96×10^(-6)and 1.71×10^(-7)mol·L^(-1),respectively.Notably,the system exhibited 99%fluorescence quenching ef-ficiency for TC,indicating ultra-efficient analyte recognition.The detection performance surpasses most reported lu-minescent MOF sensors,attributed to synergistic mechanisms of fluorescence resonance energy transfer(FRET)and photoinduced electron transfer(PET).CCDC:2446483.展开更多
Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether ...Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether as the recognized site for H_(2)S.The probe TCF-NS displayed a rapid-response fluorescent against H_(2)S with high sensitivity and selection but had no significant fluorescence response to other biothiols.Furthermore,TCF-NS was applied to sense H_(2)S in living cells successfully with minimized cytotoxicity and a large Stokes shift.展开更多
Butyrylcholinesterase(BChE)is a pivotal enzyme that degrades the neurotransmitter acetylcholine,which is related to learning and memory,into choline and acetic acid.BChE activity is strongly associated with various di...Butyrylcholinesterase(BChE)is a pivotal enzyme that degrades the neurotransmitter acetylcholine,which is related to learning and memory,into choline and acetic acid.BChE activity is strongly associated with various diseases,including Alzheimer’s disease,multiple sclerosis,diabetes,and lipid metabolism disorders.It also possesses pharmacological properties for combating cocaine addiction and detoxifying organophosphate poisoning.Given the significant importance of BChE in the biological and medical fields,detecting its activity and understanding its expression in the body are crucial for advancing related research.Herein,a brief review of recently reported specific fluorescence or chemiluminescence probes for quantifying and real-time monitoring BChE is provided.By utilizing unique recognition groups,these probes achieve highly selective identification of BChE and effectively resist interference from other biological factors.Probes demonstrate excellent performance in measuring BChE activity,screening BChE inhibitors,and locating BChE in cells and mice.These also offer strong technical support for early diagnosis,precise intervention,and effective treatment of diseases with pathological changes in BChE.展开更多
Cutaneous squamous cell carcinoma(cSCC),the second most common skin cancer,requires early and accurate detection to optimize clinical management.Fluorescence imaging has emerged as a non-invasive and cost-effective to...Cutaneous squamous cell carcinoma(cSCC),the second most common skin cancer,requires early and accurate detection to optimize clinical management.Fluorescence imaging has emerged as a non-invasive and cost-effective tool with high sensitivity for tumor diagnosis;however,existing probes for cSCC are limited in achieving rapid and specific imaging.In this study,we introduce FC-1,a dualtandem activatable fluorescent probe designed for precise cSCC diagnosis by simultaneously targeting fibroblast activation proteinαand cathepsin C(CTSC).This dual-locked activation strategy effectively reduces nonspecific signals in normal tissues while enhancing diagnostic specificity.In vivo studies in SCC-7 xenografted mice demonstrated FC-1's ability to visualize subcutaneous tumors with high sensitivity and specificity.Moreover,FC-1 enabled clear differentiation between cSCC and keloids.The probe's dual-activation mechanism and robust performance underscore its potential as a clinically translatable tool for early cSCC detection and differential diagnosis.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2010CB922902.
文摘We present our experiment on magnetic field induced spectroscopy of the ^(1)S0–^(3)P0 transition of ^(88)Sr atoms with a 10 Hz linewidth laser.The ^(88)Sr atoms are cooled by two stage laser cooling.After the second stage narrow line laser cooling,the temperature of the atoms is reduced to~3μK.The atoms are then loaded into an 813 nm one-dimensional optical lattice.A homemade 698 nm laser with 10 Hz linewidth and maximum intensity of more than 100 W/cm2 is used to probe the ^(88)Sr atoms in the lattice.By means of a magnetic field of~1 mT and a probe laser with 50 ms pulse and~6 W/cm^(2) intensity,the Doppler free ^(88)Sr ^(1)S0–^(3)P0 transition spectrum with a linewidth of 208 Hz is obtained.
基金supported by the National Natural Science Foundation of China(Grant Nos.81788101,T2125011,and 11874338)the National Key R&D Program of China(Grant No.2018YFA0306600)+2 种基金Chinese Academy of Sciences(Grants Nos.XDC07000000,GJJSTD20200001,QYZDY-SSW-SLH004,and ZDZBGCH2021002)Anhui Initiative in Quantum Information Technologies(Grant No.AHY050000)Fundamental Research Funds for the Central Universities。
文摘Recently,magnetism in two-dimensional(2 D)van der Waals(vd W)materials has attracted wide interests.It is anticipated that these materials will stimulate discovery of new physical phenomena and novel applications.The capability to quantitatively measure the magnetism of 2 D magnetic vd W materials is essential to understand these materials.Here we report on quantitative measurements of ferromagnetic-to-paramagnetic phase transition of an atomically thin(down to 11 nm)vd W magnet,namely Cr Br_(3),with a Curie point of 37.5 K.This experiment demonstrates that surface magnetism can be quantitatively investigated,which is useful for a wide variety of potential applications.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFA0303100)the National Natural Science Foundation of China(Grant Nos.11974306 and 12034017)the Natural Science Foundation of Zhejiang Province(Grant No.2021C01002)。
文摘A central research topic in condensed matter physics is the understanding of the evolution of various phases and phase transitions under different tuning parameters such as temperature, magnetic field and pressure. To explore the pressure-induced evolution of the magnetism and Fermi surface of the heavy fermion antiferromagnet Yb Pt Bi, we performed tunnel diode oscillator based measurements under pressure at low temperatures in high magnetic fields. Our results reveal that the magnetic order strengthens and the Fermi surface shrinks as the pressure increases, which are consistent with typical observations for Yb-based heavy fermion compounds. In addition, an anomalous change in the quantum oscillation amplitudes is observed above 1.5 GPa, and determining the origin requires further study.
基金National Natural Science Foundation of China(11375239,11775275,11435014)。
文摘The nucleon spatial density distribution is of critical importance for atomic nucleus structure.The nuclei with central density depletions,usually called bubble nuclei,has been studied for more than 70 years.Based on the isospin-dependent Boltzmann-Uehling-Uhlenbeck transport model.
基金supported by the Scientific and Technological Innovation Project of the China Academy of Chinese Medical Sciences(CI2021A04013)the National Natural Science Foundation of China(82204610)+1 种基金the Qihang Talent Program(L2022046)the Fundamental Research Funds for the Central Public Welfare Research Institutes(ZZ15-YQ-041 and L2021029).
文摘Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications.
文摘A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.
文摘To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparative analysis of the probe's performance in various buffer systems revealed that buffers with high organic content are unsuitable for evaluating such probes.Furthermore,the pH of the solvent system was found to significantly influence the probe's behavior.Under highly acidic conditions(pH≤2),DHU‑NP‑4 exhibited exceptional specificity for Fe^(3+),while in alkaline conditions,it demonstrated high specificity for Cu^(2+).Leveraging these properties,the probe enabled the quantitative detection of Fe^(3+)and Cu^(2+)in solution.
基金supported by the National Natural Science Foundation of China(No.U21A20290)Guangdong Basic and Applied Basic Research Foundation(No.2022A1515011656)+2 种基金the Projects of Talents Recruitment of GDUPT(No.2023rcyj1003)the 2022“Sail Plan”Project of Maoming Green Chemical Industry Research Institute(No.MMGCIRI2022YFJH-Y-024)Maoming Science and Technology Project(No.2023382).
文摘The presence of aluminum(Al^(3+))and fluoride(F^(−))ions in the environment can be harmful to ecosystems and human health,highlighting the need for accurate and efficient monitoring.In this paper,an innovative approach is presented that leverages the power of machine learning to enhance the accuracy and efficiency of fluorescence-based detection for sequential quantitative analysis of aluminum(Al^(3+))and fluoride(F^(−))ions in aqueous solutions.The proposed method involves the synthesis of sulfur-functionalized carbon dots(C-dots)as fluorescence probes,with fluorescence enhancement upon interaction with Al^(3+)ions,achieving a detection limit of 4.2 nmol/L.Subsequently,in the presence of F^(−)ions,fluorescence is quenched,with a detection limit of 47.6 nmol/L.The fingerprints of fluorescence images are extracted using a cross-platform computer vision library in Python,followed by data preprocessing.Subsequently,the fingerprint data is subjected to cluster analysis using the K-means model from machine learning,and the average Silhouette Coefficient indicates excellent model performance.Finally,a regression analysis based on the principal component analysis method is employed to achieve more precise quantitative analysis of aluminum and fluoride ions.The results demonstrate that the developed model excels in terms of accuracy and sensitivity.This groundbreaking model not only showcases exceptional performance but also addresses the urgent need for effective environmental monitoring and risk assessment,making it a valuable tool for safeguarding our ecosystems and public health.
基金supported by the National Natural Science Foundation of China(Nos.82272067,81974386,M-0696,and 82273486)Natural Science Foundation of Hunan Province(Nos.2022JJ80052,2024JJ6596)the Innovation Fund for Postgraduate Students of Central South University(No.2023ZZTS0841)。
文摘Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a serious threat to the long-term survival rate of the CRC patients.Recent studies have shown that relative higher viscosity was presented in tumor cells compared to that in normal cells,leading to viscosity as a potential biomarker for CRC.Herein,we reported the development of a series of novel viscosity-sensitive and mitochondria-specific fluorescent probes(HTB,HTI,and HTP)for CRC detection.Among them,HTB showed high sensitivity,minimal background interference,low cytotoxicity,and significant viscous response capability,making it an ideal tool for distinguishing colorectal tumor cells from normal cells.Importantly,we have successfully utilized HTB to visualize in a CRC-cells-derived xenograft(CDX)model,enriching its medical imaging capacity,which laid a foundation for further clinical translational application.
基金supported by the Natural Science Foundation of Tianjin(Nos.18JCQNJC72400 and 22JCQNJC01510).
文摘Tetracycline(TC)is a broad-spectrum antibiotic,and its residues in the environment and food are harmful to human health.Therefore,it is essential to rapidly,sensitively,and conveniently detect TC.In this work,we developed a portable silicon nanoparticles chelated Europium(Ⅲ)-based polyacrylonitrile(Eu-SiNPs/PAN)nanofiber membrane for rapid,sensitive,and convenient detection of TC.The Eu-SiNPs were synthesized with a facile one-pot method.The Eu-SiNPs/PAN nanofiber membrane was fabricated by electrospinning,combining Eu-SiNPs and PAN with three-dimensional porous membrane structures and UV resistance.Both the Eu-SiNPs and the Eu-SiNPs/PAN nanofiber membranes have good selectivity and anti-interference ability towards TC.The combined merits of rapid response,long storage life,easy portability,and naked-eye recognition of TC make the Eu-SiNPs/PAN nanofiber membrane a promising material for convenient TC detection applications.The practicability of these nanofiber membranes was further verified by detecting TC in real samples,such as lake water,drinking water and honey,and achieved quantitative detection.
基金the National Natural Science Foundation of China(Nos.22325703,22377071,U23A6009)Research Project Supported by Shanxi Scholarship Council of China(No.2022-002)+1 种基金the Shanxi Province Science Foundation(No.202203021221009)Shanxi Province Science and Technology activities for overseas people selected funding project(No.2024001)。
文摘Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint deformity and dysfunction in severe cases.The pathologic development of RA involves complex interactions of multiple biomarkers,and detecting a single biomarker may produce falsepositive results due to other confounding factors.Therefore,fluorescent probes that can detect multiple biomarkers simultaneously are crucial for precise RA diagnosis.Peroxynitrite(ONOO^(-)) and viscosity are inflammation-related factors in cells.In this study,we developed a dual responsive near-infrared fluorescent probe,YLS,for ONOO^(-) and viscosity.The probe features dual-channel turn-on fluorescence responses at 625 and 760 nm upon the presence of ONOO^(-) and viscosity,respectively.Supported by YLS,we found that during RA pathology,lymphocyte infiltration not only increases the concentration of proteins in the joint fluid resulting in elevated viscosity;at the same time,the overproduction of ONOO^(-) exacerbates oxidative stress and inflammatory responses.This multiparameter assay is expected to improve the diagnostic accuracy of the early stages of RA,thus providing a scientific basis for early intervention and personalized treatment.
基金Project supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grant No.T2221002)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.12305286)。
文摘Inductive-pulsed plasma thruster is an in-space propulsion device that generates thrust by ionizing and accelerating plasma through pulsed electromagnetic field.In this paper,the correlation between plasma structure evolution and magnetic field permeability is studied using a B-dot probe array system,combing with high-speed camera and electrical parameter measurement.Further discussions explained the mechanism how the magnetic permeation characteristics affect the energy deposition between circuit and plasma.
文摘In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission spectrum range:640-740 nm)and coumarin fluorophore(emission spectrum range:440-600 nm)as signal output units,thereby achieving effective spectral separation and highly selective detection of HClO.Under physiological pH conditions,HClO triggers an oxidation-cleavage reaction,releasing methylene blue and coumarin,which emit distinct red and green fluorescence,respectively.This dual-emission feature enabled rapid HClO detection with two-channel detection limits of 25.13 nmol·L^(-1)(green channel)and 31.55 nmol·L^(-1)(red channel).Furthermore,in cell imaging experiments,this probe demonstrated excellent cell membrane permeability and low cytotoxicity,successfully enabling the monitoring of both endogenous and exogenous HClO in living cells.By incorporating a twochannel self-calibration system,the probe effectively mitigated signal variations caused by instrumental or environmental interference,substantially improving detection sensitivity and reliability.
文摘This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwellian and triple-Maxwellian Electron Energy Distribution Function(EEDF)plasmas.Discus⁃sion and demonstration of procedures include the treatment of the ion saturation current,electron saturation cur⁃rent,space-charge effects on the I-V trace,and most importantly how to properly isolate and fit for each electron group present in an I-V trace reflecting a mult-Maxwellian EEDF,as well as how having a multi-Maxwellian EEDF affects the procedures of treating the ion and electron saturation currents.Shortcomings of common improp⁃er procedures are discussed and demonstrated with simulated I-V traces to show how these procedures gives false measurements.
文摘Herein,a one-pot chemical reduction method was reported to prepare folic acid(FA)-stabilized silver nanoclusters(FA@Ag NCs),in which FA,hydrazine hydrate,and silver nitrate were used as capping agent,reducing agent,and precursor,respectively.Several technologies were employed to investigate the structures and optical properties of FA@Ag NCs,including transmission electron microscopy(TEM),X-ray photoelectron spectrometer(XPS),Fourier transform infrared spectrometer(FTIR),X-ray diffractometer(XRD),fluorescence spectrometer,and ultraviolet visible absorption spectrometer.FA@Ag NCs were suggested to be highly dispersed and spherical with a size of around 2.8 nm.Moreover,the maximum excitation and emission wavelengths of FA@Ag NCs were 370 and 447 nm,respectively.Under the optimal detection conditions,FA@Ag NCs could be used to effectively detect malachite green with the linear detection range of 0.5-200μmol·L^(-1).The detection limit was 0.084μmol·L^(-1).The fluorescence-quenching mechanism was ascribed to the static quenching.The detection system based on FA@AgNCs was successfully used for the detection of malachite green in actual samples with good accuracy and reproducibility.
文摘The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.
文摘Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed for the dual-functional detection of environmental pollutants.This fluorescence-quenching-based sensor exhibited excep-tional sensitivity for both 2,4,6-trinitrophenol(TNP)and tetracycline(TC),achieving remarkably low detection lim-its of 1.96×10^(-6)and 1.71×10^(-7)mol·L^(-1),respectively.Notably,the system exhibited 99%fluorescence quenching ef-ficiency for TC,indicating ultra-efficient analyte recognition.The detection performance surpasses most reported lu-minescent MOF sensors,attributed to synergistic mechanisms of fluorescence resonance energy transfer(FRET)and photoinduced electron transfer(PET).CCDC:2446483.
基金financially supported by the Natural Science Foundation of Jiangsu Province(Grant No.BK20241181)the State Key Laboratory of AnalyticalChemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University(Grant No.SKLACLS2419)。
文摘Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether as the recognized site for H_(2)S.The probe TCF-NS displayed a rapid-response fluorescent against H_(2)S with high sensitivity and selection but had no significant fluorescence response to other biothiols.Furthermore,TCF-NS was applied to sense H_(2)S in living cells successfully with minimized cytotoxicity and a large Stokes shift.
基金financial support from the National Natural Science Foundation of China(Nos.82173652 and 81872728)the Natural Science Foundation of Jiangsu Province(No.BK20221522)+1 种基金Support from Jiangsu“333 High Level Talents Cultivation”Leading Talents(No.2022-3-16-203)the Qing Lan Project is also appreciated.
文摘Butyrylcholinesterase(BChE)is a pivotal enzyme that degrades the neurotransmitter acetylcholine,which is related to learning and memory,into choline and acetic acid.BChE activity is strongly associated with various diseases,including Alzheimer’s disease,multiple sclerosis,diabetes,and lipid metabolism disorders.It also possesses pharmacological properties for combating cocaine addiction and detoxifying organophosphate poisoning.Given the significant importance of BChE in the biological and medical fields,detecting its activity and understanding its expression in the body are crucial for advancing related research.Herein,a brief review of recently reported specific fluorescence or chemiluminescence probes for quantifying and real-time monitoring BChE is provided.By utilizing unique recognition groups,these probes achieve highly selective identification of BChE and effectively resist interference from other biological factors.Probes demonstrate excellent performance in measuring BChE activity,screening BChE inhibitors,and locating BChE in cells and mice.These also offer strong technical support for early diagnosis,precise intervention,and effective treatment of diseases with pathological changes in BChE.
基金supported by the National Natural Science Foundation of China(No.22325401,22404049)Special Funds for the Construction of Innovative Provinces in Hunan Province(No.2021RC4021)the China Postdoctoral Science Foundation(No.2024 M750866).
文摘Cutaneous squamous cell carcinoma(cSCC),the second most common skin cancer,requires early and accurate detection to optimize clinical management.Fluorescence imaging has emerged as a non-invasive and cost-effective tool with high sensitivity for tumor diagnosis;however,existing probes for cSCC are limited in achieving rapid and specific imaging.In this study,we introduce FC-1,a dualtandem activatable fluorescent probe designed for precise cSCC diagnosis by simultaneously targeting fibroblast activation proteinαand cathepsin C(CTSC).This dual-locked activation strategy effectively reduces nonspecific signals in normal tissues while enhancing diagnostic specificity.In vivo studies in SCC-7 xenografted mice demonstrated FC-1's ability to visualize subcutaneous tumors with high sensitivity and specificity.Moreover,FC-1 enabled clear differentiation between cSCC and keloids.The probe's dual-activation mechanism and robust performance underscore its potential as a clinically translatable tool for early cSCC detection and differential diagnosis.
