We report on soft c-axis point-contact Andreev reflection(PCAR)spectroscopy combining with resistivity measurements on BaFe_(2)(As_(0.7)P_(0.3))_(2),to elucidate the superconducting gap structure in the vicinity of th...We report on soft c-axis point-contact Andreev reflection(PCAR)spectroscopy combining with resistivity measurements on BaFe_(2)(As_(0.7)P_(0.3))_(2),to elucidate the superconducting gap structure in the vicinity of the quantum critical point.A double peak at the gap edge plus a dip feature at zero-bias has been observed on the PCAR spectra,indicative of the presence of a nodeless gap in BaFe_(2)(As_(0.7)P_(0.3))_(2).Detailed analysis within a sophisticated theoretical model reveals an anisotropic gap with deep gap minima.The PCARs also feature additional structures related to the electron-bosonic coupling mode.Using the extracted superconducting energy gap value,a characteristic bosonic energy Ω_(b) and its temperature dependence are obtained,comparable with the spin-resonance energy observed in neutron scattering experiment.These results indicate a magnetism-driven quantum critical point in the BaFe_(2)(As_(1-x)P_(x))_(2) system.展开更多
BACKGROUND Prior research has demonstrated that the brains of adolescents with depression exhibit distinct structural alterations.However,preliminary studies have documented the pathophysiological changes in certain b...BACKGROUND Prior research has demonstrated that the brains of adolescents with depression exhibit distinct structural alterations.However,preliminary studies have documented the pathophysiological changes in certain brain regions,such as the cerebellum,highlighting a need for further research to support the current understanding of this disease.AIM To study brain changes in depressed adolescents.METHODS This study enrolled 34 adolescents with depression and 34 age-,sex-,and education-level-matched healthy control(HC)individuals.Structural and functional alterations were identified when comparing the brains of these two participant groups through voxel-based morphometry and cerebral blood flow(CBF)analysis,respectively.Associations between identified brain alterations and the severity of depressive symptoms were explored through Pearson correlation analyses.RESULTS The cerebellum,superior frontal gyrus,cingulate gyrus,pallidum,middle frontal gyrus,angular gyrus,thalamus,precentral gyrus,inferior temporal gyrus,superior temporal gyrus,inferior frontal gyrus,and supplementary motor areas of adolescents with depression showed an increase in brain volume compared to HC individuals.These patients with depression further presented with a pronounced drop in CBF in the left pallidum(group=98,and peak t=-4.4324),together with increased CBF in the right percental gyrus(PerCG)(group=90,and peak t=4.5382).In addition,17-item Hamilton Depression Rating Scale scores were significantly correlated with the increased volume in the opercular portion of the left inferior frontal gyrus(r=-0.5231,P<0.01).CONCLUSION The right PerCG showed structural and CBF changes,indicating that research on this part of the brain could offer insight into the pathophysiological causes of impaired cognition.展开更多
Objective:To study the mechanism of action of Yanghe Huayan Decoction on endocrine-resistant cells(MCF-7R/mTOR cells)with low expression of mTOR;Methods:CCK-8 assay and cell clone assay were used to detect cell prolif...Objective:To study the mechanism of action of Yanghe Huayan Decoction on endocrine-resistant cells(MCF-7R/mTOR cells)with low expression of mTOR;Methods:CCK-8 assay and cell clone assay were used to detect cell proliferation and clonal ability,and flow cytometry was used to detect cell apoptosis.The changes of cytokines in ER-PI3K/Akt/mTOR signaling pathway were analyzed by blot and QPCR.Results:Yanghe Huayan Decoction could significantly affect the proliferation(p<0.05)and cloning ability(p<0.05)of MCF-7R/mTOR cells,promote cell apoptosis(p<0.01),and downregulate the expression of ER,PI3K,AKT,mTOR and p-mTOR(p<0.05).Conclusion:Yanghe Huayan Decoction can regulate the ER-PI3K/Akt/mTOR signaling pathway with multiple targets,and the use of combined mTOR inhibitors can regulate the ER-PI3K/Akt/mTOR signaling pathway more significantly.展开更多
Lithium-ion batteries(LIBs)with extreme fast charging(XFC)capability are considered an effective way to alleviate range anxiety for electric vehicle(EV)buyers.Owing to the high ionic and electronic conductivity of LiN...Lithium-ion batteries(LIBs)with extreme fast charging(XFC)capability are considered an effective way to alleviate range anxiety for electric vehicle(EV)buyers.Owing to the high ionic and electronic conductivity of LiNi_(x)Co_(y)Mn_zO_(2)(x+y+z=1,NCM)cathodes,the inevitable Li plating of graphite in NCM|graphite cell is usually identified as a key bottleneck for XFC LIBs.However,the capacity decay mechanism of cathode materials under XFC has not been fully investigated.In this work,three typical NCM cathode materials with different Ni fractions were chosen and their electrochemical performances under XFC associated with structural evolution were investigated.A faster capacity decay of NCMs under XFC conditions is observed,especially for Ni-rich NCMs.In-situ X-ray diffraction(XRD)reveals that the multiple caxis parameters appear at the high-voltage regions in Nirich NCMs,which is probably triggered by the larger obstruction of Li(de)intercalation.Particularly,NCMs with moderate Ni fraction also present a similar trend under XFC conditions.This phenomenon is more detrimental to the structural and morphological stability,resulting in a faster capacity decay than that under low current charging.This work provides new insight into the degradation mechanism of NCMs under XFC conditions,which can promote the development of NCM cathode materials with XFC capability.展开更多
Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was disclosed.The reaction can undergo selective mono-or triple ...Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was disclosed.The reaction can undergo selective mono-or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer(HAT)catalyst under visible-light-induced conditions at room temperature.Foramte acts as both the C1 source and the reductant through the generation of CO_(2)^(·-)species,which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process.展开更多
A series of unreported fullerodihydropyridine-3-ones were synthesized as a new family of fullerene derivatives in moderate to good yields by a simple one-step reaction of[60]fullerene with cheap and readily available ...A series of unreported fullerodihydropyridine-3-ones were synthesized as a new family of fullerene derivatives in moderate to good yields by a simple one-step reaction of[60]fullerene with cheap and readily available β-substituted ethylamines in the absence or presence of arylacetaldehydes under the assistance of Cu(OAc)_(2).The in situ generation of arylacetaldehydes by the C—N bond cleavage of arylethylamines avoided their complex synthesis in advance and realized the preparation of fullerodihydropyridine-3-ones with structural and functional diversities,which may have promising applications in perovskite solar cells to improve the performance of photovoltaic devices due to the existence of a largeπ-conjugated system on the dihydropyridine-3-one ring.展开更多
Circulating tumor cells(CTCs)have the potential to provide genetic information for heterogeneous tumors,which may be useful for monitoring disease progression and developing personalized therapies.However,the isolatio...Circulating tumor cells(CTCs)have the potential to provide genetic information for heterogeneous tumors,which may be useful for monitoring disease progression and developing personalized therapies.However,the isolation of CTCs for molecular analysis is challenging due to their extreme rarity and phenotypic heterogeneity,which hinders the transformation of CTCs into traditional clinical applications.In order to achieve clinically significant CTC detection,devices utilizing novel microfluidics and nanotechnology have been developed to achieve high sensitivity and specificity capture of CTCs.In this review,we discuss these newly developed devices for CTC capture and molecular characterization for early diagnosis and determining ideal treatment regimen to better manage these cancers clinically.In addition,the potential prognostic values of CTCs as treatment guidelines and that ultimately contribute to realize personalized treatment are also discussed.展开更多
The nucleation of crystals is often a determining step in the phase transition of materials,but it remains a challenge to control the density and specific location of nuclei simultaneously.Here we fabricated the isola...The nucleation of crystals is often a determining step in the phase transition of materials,but it remains a challenge to control the density and specific location of nuclei simultaneously.Here we fabricated the isolated single crystals of uniform size with controlled number density and spatial distribution by self-nucleation of patterned dendritic crystals.Imprint lithography creates the periodic void space on the surface of poly(ethylene oxide)-b-poly(2-vinyl pyridine)(PEO-b-P2VP)block copolymer thin films and provides spatial redistribution of polymers,leading to the preferential nucleation and subsequent oriented growth of dendrites in the periodic arrays of imprinted lines.The morphology and thermal stability of the patterned crystals can be adjusted by tuning embossing conditions(e.g.,temperature and pressure).Furthermore,in the self-nucleation technique,the annealing temperature and heating rate are used as the feedback parameters to map the number density and spatial distribution of regrown single crystals.Such PEO-b-P2VP crystalline pattern can be used as a versatile template for large-area manufacturing of selective metal patterns for electronic devices and other applications.展开更多
The tool state exerts a strong influence on surface quality and profile accuracy during precision/ultraprecision machining.However,current on-machine measurement methods cannot precisely obtain the tool nose radius an...The tool state exerts a strong influence on surface quality and profile accuracy during precision/ultraprecision machining.However,current on-machine measurement methods cannot precisely obtain the tool nose radius and wear.This study therefore investigated the onmachine measurement of tool nose radius on the order of hundreds of microns and wear on the order of a few microns to tens of microns during precision/ultra-precision machining using the edge reversal method.To provide the necessary replication,pure aluminum and pure copper soft metal substrates were evaluated,with pure copper exhibiting superior performance.The feasibility of the measurement method was then demonstrated by evaluating the replication accuracy using a 3D surface topography instrument;the measurement error was only 0.1%.The wear of the cutting tool was measured using the proposed method to obtain the maximum values for tool arc wear,flank wear,and wear depth of 3.4 lm,73.5 lm and 3.7 lm,respectively.展开更多
Exploiting the concept of the dinuclear system,the interaction potential energy of two fragments that are quite close to each other is analyzed.A semi-classical method is used to calculate fission fragment yields usin...Exploiting the concept of the dinuclear system,the interaction potential energy of two fragments that are quite close to each other is analyzed.A semi-classical method is used to calculate fission fragment yields using a simplified two-dimensional scission-point model.By considering the tip-to-tip orientation at the scission point of the fission process,we investigate the mass,charge,and kinetic-energy distributions of the fission fragments,for excitation energies in the 0-20 MeV range.Our results show that the fission fragment distributions are reproduced quite well,including the recent experimental results for the isotone chain[D Ramos et al.Phys.Rev.C 97,054612(2018)].Thus,the simplified model is useful for multi-parameter global measurements of fission products.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11774303 and 11574373)the National Key Research and Development Program of China(Grant Nos.2022YFA1403402,2021YFA1400401,and 2020YFA0406003)+1 种基金the Chinese Academy of Sciences(Grant Nos.XDB33000000 and GJTD-2020-01)financial support from the Joint Fund of Yunnan Provincial Science and Technology Department(Grant No.2019FY003008)。
文摘We report on soft c-axis point-contact Andreev reflection(PCAR)spectroscopy combining with resistivity measurements on BaFe_(2)(As_(0.7)P_(0.3))_(2),to elucidate the superconducting gap structure in the vicinity of the quantum critical point.A double peak at the gap edge plus a dip feature at zero-bias has been observed on the PCAR spectra,indicative of the presence of a nodeless gap in BaFe_(2)(As_(0.7)P_(0.3))_(2).Detailed analysis within a sophisticated theoretical model reveals an anisotropic gap with deep gap minima.The PCARs also feature additional structures related to the electron-bosonic coupling mode.Using the extracted superconducting energy gap value,a characteristic bosonic energy Ω_(b) and its temperature dependence are obtained,comparable with the spin-resonance energy observed in neutron scattering experiment.These results indicate a magnetism-driven quantum critical point in the BaFe_(2)(As_(1-x)P_(x))_(2) system.
基金Supported by The Project of Scientific Research and Innovative Experiment for College Students in Chongqing Medical University,No.202215the Provincial Project of University Students Innovation and Entrepreneurship Training Program,No.202210631015.
文摘BACKGROUND Prior research has demonstrated that the brains of adolescents with depression exhibit distinct structural alterations.However,preliminary studies have documented the pathophysiological changes in certain brain regions,such as the cerebellum,highlighting a need for further research to support the current understanding of this disease.AIM To study brain changes in depressed adolescents.METHODS This study enrolled 34 adolescents with depression and 34 age-,sex-,and education-level-matched healthy control(HC)individuals.Structural and functional alterations were identified when comparing the brains of these two participant groups through voxel-based morphometry and cerebral blood flow(CBF)analysis,respectively.Associations between identified brain alterations and the severity of depressive symptoms were explored through Pearson correlation analyses.RESULTS The cerebellum,superior frontal gyrus,cingulate gyrus,pallidum,middle frontal gyrus,angular gyrus,thalamus,precentral gyrus,inferior temporal gyrus,superior temporal gyrus,inferior frontal gyrus,and supplementary motor areas of adolescents with depression showed an increase in brain volume compared to HC individuals.These patients with depression further presented with a pronounced drop in CBF in the left pallidum(group=98,and peak t=-4.4324),together with increased CBF in the right percental gyrus(PerCG)(group=90,and peak t=4.5382).In addition,17-item Hamilton Depression Rating Scale scores were significantly correlated with the increased volume in the opercular portion of the left inferior frontal gyrus(r=-0.5231,P<0.01).CONCLUSION The right PerCG showed structural and CBF changes,indicating that research on this part of the brain could offer insight into the pathophysiological causes of impaired cognition.
基金National Natural Science Foundation of China(No.81573989)
文摘Objective:To study the mechanism of action of Yanghe Huayan Decoction on endocrine-resistant cells(MCF-7R/mTOR cells)with low expression of mTOR;Methods:CCK-8 assay and cell clone assay were used to detect cell proliferation and clonal ability,and flow cytometry was used to detect cell apoptosis.The changes of cytokines in ER-PI3K/Akt/mTOR signaling pathway were analyzed by blot and QPCR.Results:Yanghe Huayan Decoction could significantly affect the proliferation(p<0.05)and cloning ability(p<0.05)of MCF-7R/mTOR cells,promote cell apoptosis(p<0.01),and downregulate the expression of ER,PI3K,AKT,mTOR and p-mTOR(p<0.05).Conclusion:Yanghe Huayan Decoction can regulate the ER-PI3K/Akt/mTOR signaling pathway with multiple targets,and the use of combined mTOR inhibitors can regulate the ER-PI3K/Akt/mTOR signaling pathway more significantly.
基金financially supported by the National Key R&D Program of China(No.2020YFA0406203)Shenzhen Science and Technology Innovation Commission(Nos.JCYJ20180507181806316,JCYJ20200109105618137 and SGDX2019081623240948)+1 种基金the ECS scheme(Nos.City U21307019,7005500,7005615,7005612 and 7020043)Shenzhen Research Institute,City University of Hong Kong。
文摘Lithium-ion batteries(LIBs)with extreme fast charging(XFC)capability are considered an effective way to alleviate range anxiety for electric vehicle(EV)buyers.Owing to the high ionic and electronic conductivity of LiNi_(x)Co_(y)Mn_zO_(2)(x+y+z=1,NCM)cathodes,the inevitable Li plating of graphite in NCM|graphite cell is usually identified as a key bottleneck for XFC LIBs.However,the capacity decay mechanism of cathode materials under XFC has not been fully investigated.In this work,three typical NCM cathode materials with different Ni fractions were chosen and their electrochemical performances under XFC associated with structural evolution were investigated.A faster capacity decay of NCMs under XFC conditions is observed,especially for Ni-rich NCMs.In-situ X-ray diffraction(XRD)reveals that the multiple caxis parameters appear at the high-voltage regions in Nirich NCMs,which is probably triggered by the larger obstruction of Li(de)intercalation.Particularly,NCMs with moderate Ni fraction also present a similar trend under XFC conditions.This phenomenon is more detrimental to the structural and morphological stability,resulting in a faster capacity decay than that under low current charging.This work provides new insight into the degradation mechanism of NCMs under XFC conditions,which can promote the development of NCM cathode materials with XFC capability.
基金supported by the National Natural Science Foundation of China(22001224)the Natural Science Foundation of Jiangsu Province(BK20201014,BK20200106)+2 种基金the Start-up Funding provided by Xuzhou Medical Universityalso supported by the Jiangsu Specially-Appointed Professor Program(Xu Zhu)Jiangsu Province Shuangchuang PhD Program(Pei Xu,JSSCBS20211267)。
文摘Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was disclosed.The reaction can undergo selective mono-or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer(HAT)catalyst under visible-light-induced conditions at room temperature.Foramte acts as both the C1 source and the reductant through the generation of CO_(2)^(·-)species,which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process.
基金grateful for the financial support from the National Natural Science Foundation of China(No.22271083)the Open Project Funding of the State Key Laboratory of Biocatalysis and Enzyme Engineering(No.SKLBEE2021026)the Innovation and Entrepreneurship Training Program for Undergraduates of Hubei University(No.X202210512001).
文摘A series of unreported fullerodihydropyridine-3-ones were synthesized as a new family of fullerene derivatives in moderate to good yields by a simple one-step reaction of[60]fullerene with cheap and readily available β-substituted ethylamines in the absence or presence of arylacetaldehydes under the assistance of Cu(OAc)_(2).The in situ generation of arylacetaldehydes by the C—N bond cleavage of arylethylamines avoided their complex synthesis in advance and realized the preparation of fullerodihydropyridine-3-ones with structural and functional diversities,which may have promising applications in perovskite solar cells to improve the performance of photovoltaic devices due to the existence of a largeπ-conjugated system on the dihydropyridine-3-one ring.
基金the National Natural Science Foundation of China(31800085)National Natural Science Foundation for Major Research Instruments(81527801)
文摘Circulating tumor cells(CTCs)have the potential to provide genetic information for heterogeneous tumors,which may be useful for monitoring disease progression and developing personalized therapies.However,the isolation of CTCs for molecular analysis is challenging due to their extreme rarity and phenotypic heterogeneity,which hinders the transformation of CTCs into traditional clinical applications.In order to achieve clinically significant CTC detection,devices utilizing novel microfluidics and nanotechnology have been developed to achieve high sensitivity and specificity capture of CTCs.In this review,we discuss these newly developed devices for CTC capture and molecular characterization for early diagnosis and determining ideal treatment regimen to better manage these cancers clinically.In addition,the potential prognostic values of CTCs as treatment guidelines and that ultimately contribute to realize personalized treatment are also discussed.
基金financially supported by the National Natural Science Foundation of China(Nos.51973202,51773182,U1804144,52003247 and 11872338)the China Postdoctoral Science Foundation(No.2020M682340)+2 种基金the Young Outstanding Teachers of University in Henan Province(No.2019GGJS003)the Postdoctoral Research Grant in Henan Province(No.201901009)the Startup Research Fund of Zhengzhou University(No.32211191).
文摘The nucleation of crystals is often a determining step in the phase transition of materials,but it remains a challenge to control the density and specific location of nuclei simultaneously.Here we fabricated the isolated single crystals of uniform size with controlled number density and spatial distribution by self-nucleation of patterned dendritic crystals.Imprint lithography creates the periodic void space on the surface of poly(ethylene oxide)-b-poly(2-vinyl pyridine)(PEO-b-P2VP)block copolymer thin films and provides spatial redistribution of polymers,leading to the preferential nucleation and subsequent oriented growth of dendrites in the periodic arrays of imprinted lines.The morphology and thermal stability of the patterned crystals can be adjusted by tuning embossing conditions(e.g.,temperature and pressure).Furthermore,in the self-nucleation technique,the annealing temperature and heating rate are used as the feedback parameters to map the number density and spatial distribution of regrown single crystals.Such PEO-b-P2VP crystalline pattern can be used as a versatile template for large-area manufacturing of selective metal patterns for electronic devices and other applications.
基金the financial support provided by the National Key Research and Development Program(Grant No.2018YFA0702900)the National Natural Science Foundation of China(Grant No.51975096).
文摘The tool state exerts a strong influence on surface quality and profile accuracy during precision/ultraprecision machining.However,current on-machine measurement methods cannot precisely obtain the tool nose radius and wear.This study therefore investigated the onmachine measurement of tool nose radius on the order of hundreds of microns and wear on the order of a few microns to tens of microns during precision/ultra-precision machining using the edge reversal method.To provide the necessary replication,pure aluminum and pure copper soft metal substrates were evaluated,with pure copper exhibiting superior performance.The feasibility of the measurement method was then demonstrated by evaluating the replication accuracy using a 3D surface topography instrument;the measurement error was only 0.1%.The wear of the cutting tool was measured using the proposed method to obtain the maximum values for tool arc wear,flank wear,and wear depth of 3.4 lm,73.5 lm and 3.7 lm,respectively.
基金Supported by National Natural Science Foundation of China(11875301,U1832167)。
文摘Exploiting the concept of the dinuclear system,the interaction potential energy of two fragments that are quite close to each other is analyzed.A semi-classical method is used to calculate fission fragment yields using a simplified two-dimensional scission-point model.By considering the tip-to-tip orientation at the scission point of the fission process,we investigate the mass,charge,and kinetic-energy distributions of the fission fragments,for excitation energies in the 0-20 MeV range.Our results show that the fission fragment distributions are reproduced quite well,including the recent experimental results for the isotone chain[D Ramos et al.Phys.Rev.C 97,054612(2018)].Thus,the simplified model is useful for multi-parameter global measurements of fission products.
