In this paper, we introduce the pre-frame operator Q for the g-frame in a complex Hilbert space, which will play a key role in studying g-frames and g-Riesz bases etc. Using the pre-frame operator Q, we give some nece...In this paper, we introduce the pre-frame operator Q for the g-frame in a complex Hilbert space, which will play a key role in studying g-frames and g-Riesz bases etc. Using the pre-frame operator Q, we give some necessary and sufficient conditions for a g-Bessel sequence, a g-frame, and a g-Riesz basis in a complex Hilbert space, which have properties similar to those of the Bessel sequence, frame, and Riesz basis respectively. We also obtain the relation between a g-frame and a g-Riesz basis, and the relation of bounds between a g-frame and a g-Riesz basis. Lastly, we consider the stability of a g-frame or a g-Riesz basis for a Hilbert space under perturbation.展开更多
A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yiel...A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yields under mild conditions by an unprecedented mode involving β’-carbon of α-substituted allenes and the proposed mechanism is supported by capturing the intermediate.Moreover,this class of benzazepine derivatives exhibited potential ability of cytotoxicity toward cancer cells.展开更多
Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To thi...Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To this end,this study combined the Weather Research and Forecasting(WRF)model with the Wind Farm Parameterization(WFP)method to investigate the wake characteristics and operational performance of large onshore wind farms in the complex terrain of Jiuquan City,Gansu Province,China.The research results showed that after verification,the systematic error of the WRF simulations was less than 3%.The WRF model and the WFP scheme simulated a significant warming phenomenon within the wind power base area,while a cooling effect was observed outside.The analysis of the wake effects indicated that the impact of PhaseⅠconstruction on PhaseⅡconstruction of the wind power base was minimal.During the operation of the entire wind power base,the wind speed within the wind farm decreased by approximately 10%,and the influence range of the predominant wind direction extended over a hundred kilometers downwind.The research conclusions provide a powerful scientific basis for optimizing design and operation,improving efficiency,minimizing the negative impacts on adjacent wind turbines,and ensuring the sustainable development of wind energy through dynamic planning and scientific assessment.展开更多
Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi...Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi-stego images provides good image quality but often results in low embedding capability.To address these challenges,this paper proposes a high-capacity RDH scheme based on PVO that generates three stego images from a single cover image.The cover image is partitioned into non-overlapping blocks with pixels sorted in ascending order.Four secret bits are embedded into each block’s maximum pixel value,while three additional bits are embedded into the second-largest value when the pixel difference exceeds a predefined threshold.A similar embedding strategy is also applied to the minimum side of the block,including the second-smallest pixel value.This design enables each block to embed up to 14 bits of secret data.Experimental results demonstrate that the proposed method achieves significantly higher embedding capacity and improved visual quality compared to existing triple-stego RDH approaches,advancing the field of reversible steganography.展开更多
Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstan...Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstanding performance across various domains,thereby prompting researchers to investigate their applicability in recommendation systems.However,due to the lack of task-specific knowledge and an inefficient feature extraction process,LLMs still have suboptimal performance in recommendation tasks.Therefore,external knowledge sources,such as knowledge graphs(KGs)and knowledge bases(KBs),are often introduced to address the issue of data sparsity.Compared to KGs,KBs possess higher retrieval efficiency,making them more suitable for scenarios where LLMs serve as recommenders.To this end,we introduce a novel framework integrating LLMs with KBs for enhanced retrieval generation,namely LLMKB.LLMKB initially leverages structured knowledge to create mapping dictionaries,extracting entity-relation information from heterogeneous knowledge to construct KBs.Then,LLMKB achieves the embedding calibration between user information representations and documents in KBs through retrieval model fine-tuning.Finally,LLMKB employs retrievalaugmented generation to produce recommendations based on fused text inputs,followed by post-processing.Experiment results on two public CRS datasets demonstrate the effectiveness of our framework.Our code is publicly available at the link:https://anonymous.4open.science/r/LLMKB-6FD0.展开更多
Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performa...Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performance indicators such as catalytic activity,selectivity,and stability can be effectively optimized.As a result,they become essential parameters that must be considered in the design and development of high-efficiency catalysts.This study proposes a surface engineering method to accurately control the concentration of surface LA and LB sites in defect-laden In_(2)O_(3-x)(OH)_(y)(denoted as N-n%-IO),establishing three types of LB/LA stoichiometric ratios with different photocatalytic CO_(2)hydrogenation performances.It is demonstrated that the LB-rich system(LB/LA>1)shows suppressed activity.In contrast,the balanced stoichiometric ratio system(LB/LA=1)attains an optimal methanol yield(179.79μmol g^(-1)h^(-1))and selectivity(43.67%),while the LA-rich system(LB/LA<1)exhibits the best CO production rate(1913.76μmol g^(-1)h^(-1))and selectivity(94.96%).Systematic experiments disclose that the balanced LB/LA system with adjacent surface frustrated Lewis pairs(SFLPs)can effectively facilitate the adsorption/activation of reactants,stabilize intermediates,and regulate the dynamic behavior of photo-generated carriers.However,the imbalanced LB/LA systems either lack necessary active sites or can only follow an oxygen vacancy-mediated pathway during photocatalytic CO_(2)hydrogenation.This work offers a comprehensive understanding of the crucial functions of surface Lewis acid/base sites in the product distribution of solar-driven CO_(2)reduction.展开更多
Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,ta...Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,tau is not an easy target because it dynamically interacts with microtubules and other cellular components,which presents a challenge for tau-targeted drugs.New cellular models could aid the development of mechanism-based tau-targeted therapies.展开更多
Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article ha...Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article has been corrected.展开更多
Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work pr...Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work proposes Secured-FL,a blockchain-based defensive framework that combines smart contract-based authentication,clustering-driven outlier elimination,and dynamic threshold adjustment to defend against adversarial attacks.The framework was implemented on a private Ethereum network with a Proof-of-Authority consensus algorithm to ensure tamper-resistant and auditable model updates.Large-scale simulation on the Cyber Data dataset,under up to 50%malicious client settings,demonstrates Secured-FL achieves 6%-12%higher accuracy,9%-15%lower latency,and approximately 14%less computational expense compared to the PPSS benchmark framework.Additional tests,including confusion matrices,ROC and Precision-Recall curves,and ablation tests,confirm the interpretability and robustness of the defense.Tests for scalability also show consistent performance up to 500 clients,affirming appropriateness to reasonably large deployments.These results make Secured-FL a feasible,adversarially resilient FL paradigm with promising potential for application in smart cities,medicine,and other mission-critical IoT deployments.展开更多
The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Sur...The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Surfaces",line 2:The device name was corrected from"YDFLP-E-50-M8"to"YDFLP-50-M8."Page 3,Section 2.4:The phrase"95%confidence interval"has been corrected to"95%confidence level."Page 3,Figure 1 caption:The phrase"fandg"has been corrected to"f and g."The order"C4 and C12"has been reversed to"C12 and C4,"in accordance with the display order in the figure.Page 4,Figure reference:The phrase"Figs.4c and d"has been corrected to"Figs.5b and c."Page 5,paragraph starting with"The ANOVA results are presented...":The phrase"95%confidence interval"has been corrected to"95%confidence level."展开更多
Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursi...Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursing allowances provided by the Chinese government for people with disabilities who are unable to work are not only important components of China’s social security system which provide for the needs of its disabled,but also show China’s ability to guarantee the basic living standard and social fairness and justice for this group of people.展开更多
The brain atlas,or parcellation-delineating spatial partitions,organizes the brain's structure and function[1].The spatial arrangements of highly heterogeneous landscapes represent specialized functional regions f...The brain atlas,or parcellation-delineating spatial partitions,organizes the brain's structure and function[1].The spatial arrangements of highly heterogeneous landscapes represent specialized functional regions for investigating their interactions.Early efforts to parcellate the mammalian brain,using histological cytoarchitecture and myeloarchitecture,as well as recent in vivo magnetic resonance imaging(MRl)[2,3],have primarily involved cortical areas,subcortical structures,and cerebellar nuclei.Human brain parcellations primarily focus on grey matter(GM),which purposefully excludes white matter(WM),hindering the development of next-generation brain atlases.展开更多
In this paper, by msss_mappings, the relations between metric spaces and spaces with σ _locally countable cs_networks or spaces with σ _locally countable weak bases are established. These are some answers to A...In this paper, by msss_mappings, the relations between metric spaces and spaces with σ _locally countable cs_networks or spaces with σ _locally countable weak bases are established. These are some answers to Alexandroff’s problems.展开更多
Based on the existing reports on the bioactive isatin derivatives, a number of Schiff bases were synthesized by reacting 5-substituted isatins with bioactive amines/hydrazides and their structures were confirmed using...Based on the existing reports on the bioactive isatin derivatives, a number of Schiff bases were synthesized by reacting 5-substituted isatins with bioactive amines/hydrazides and their structures were confirmed using spectroscopic methods such as NMR, IR and mass spectrometry. Furthermore, Nbenzylation of isatin followed by the Schiff base formation furnished a new series of compounds(11a-13c) which allowed the analysis of the effect of isatin N-substitution on the bioactivity of the resulting compounds. The antibacterial activity of the synthesized derivatives was evaluated using a microtiter plate method on a series of gram positive and gram negative bacterial strains. Compounds 2d, 3b, 5c and 6a were among the most potent derivatives against Pseudomonas aeruginosa(MIC = 6.25 μg/m L).Analysis of the structure-activity relationship showed that the incorporation of(thio)urea-based Schiff bases lead to more potent derivatives with a broader spectrum of antibacterial activity. In addition,highly lipophilic compounds such as 11a-12c did not show any measurable antibacterial activity, which implies that an optimal lipophilicity might be an important requirement for the antibacterial activity of the studied isatins. Finally, the finding that hydantoin derivatives of N-benzylisatins(13a-13c) still exhibit some antibacterial activity prompted us to consider exploring the bioactivity of more diverse derivatives of isatin-aminohydantoin Schiff bases(compounds 1a-1d) in our future studies.展开更多
Seven new Schiff bases, which are 4,4,4-trifluo-ro-1-(2-thienyl)-1-butanone-3-Z, Z =-thioseraicarbazone (a); -thiocarbohydrazone (b),-benzoic hydrazone (c), -( o-hydroxyphenyl) imine (d) ,-nicotinic hydrazone (e),-sal...Seven new Schiff bases, which are 4,4,4-trifluo-ro-1-(2-thienyl)-1-butanone-3-Z, Z =-thioseraicarbazone (a); -thiocarbohydrazone (b),-benzoic hydrazone (c), -( o-hydroxyphenyl) imine (d) ,-nicotinic hydrazone (e),-salicylic hydrazone (f), and -(p-fluoro-m-chlorophenyl) imine (g), have been synthesized by reaction of 4, 4, 4-trifluoro-1-(2-thienyl)-1,3-butanedione (TFTBD) with corresponding hy-drazides or anilines, acetic acid or p-toluence sulfonic acid as catalyst, and characterized by Elemental analysis, IR, UV-Vis,1H NMR and MS. The MS spectra confirmed that the -C3=O condensed with primary amino group. Tauto-merism of the compounds is discussed.展开更多
The economic transformation of the old industrial bases is a key research topic among geographers in China.In this paper,we propose that the concept of regional economic resilience(RER)has unique theoretical value in ...The economic transformation of the old industrial bases is a key research topic among geographers in China.In this paper,we propose that the concept of regional economic resilience(RER)has unique theoretical value in analyzing the economic transformation of the old industrial bases.We constructed an analytical framework and an index system and applied the conceptual tools to study the evolution of RER in the old industrial base of Liaoning Province in China,which is currently subjected to not only sudden shocks but‘slow burn’—longer term processes of change that may nevertheless affect the regional economy.There are four main findings:first,the evolution of RER in Liaoning can be divided into four stages from 2000 to 2015.Liaoning is currently in its conservation-release period,and the next stage will be a release-reorganization period.Second,the RER of the majority of the studied cities is lower than the average value for Liaoning,and this is mainly attributed to the relatively weak vulnerability-resistance and adaptability-transformation capacity of these cities.Third,the RER levels of the 14 cities in Liaoning differ significantly.At the first level is Shenyang and Dalian,at the second level is Dandong and Yingkou,and the third level comprises the remaining cities.Fourth,regional economic resilience is mainly determined by vulnerability-resistance,which indirectly reflects Liaoning’s lack of adaptability-transformation capacity,and the ability of the region to renew or create a new development path is weak.展开更多
基金the Natural Science Foundation of Fujian Province,China (No.Z0511013)the Education Commission Foundation of Fujian Province,China (No.JB04038)
文摘In this paper, we introduce the pre-frame operator Q for the g-frame in a complex Hilbert space, which will play a key role in studying g-frames and g-Riesz bases etc. Using the pre-frame operator Q, we give some necessary and sufficient conditions for a g-Bessel sequence, a g-frame, and a g-Riesz basis in a complex Hilbert space, which have properties similar to those of the Bessel sequence, frame, and Riesz basis respectively. We also obtain the relation between a g-frame and a g-Riesz basis, and the relation of bounds between a g-frame and a g-Riesz basis. Lastly, we consider the stability of a g-frame or a g-Riesz basis for a Hilbert space under perturbation.
基金financially supported by the National Natural Science Foundation of China(No.21572271).
文摘A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yields under mild conditions by an unprecedented mode involving β’-carbon of α-substituted allenes and the proposed mechanism is supported by capturing the intermediate.Moreover,this class of benzazepine derivatives exhibited potential ability of cytotoxicity toward cancer cells.
基金funded by“The Factors Affecting the Accuracy of Wind Resource Assessment and Comprehensive Post-Evaluation Techniques for Operating Wind Power Projects,”grant number YJ24.002“The Research and Application of Future Medium to Long Term Wind Resource Assessment for Wind Farms Based on Artificial Intelligence Project,”grant number 2023021。
文摘Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To this end,this study combined the Weather Research and Forecasting(WRF)model with the Wind Farm Parameterization(WFP)method to investigate the wake characteristics and operational performance of large onshore wind farms in the complex terrain of Jiuquan City,Gansu Province,China.The research results showed that after verification,the systematic error of the WRF simulations was less than 3%.The WRF model and the WFP scheme simulated a significant warming phenomenon within the wind power base area,while a cooling effect was observed outside.The analysis of the wake effects indicated that the impact of PhaseⅠconstruction on PhaseⅡconstruction of the wind power base was minimal.During the operation of the entire wind power base,the wind speed within the wind farm decreased by approximately 10%,and the influence range of the predominant wind direction extended over a hundred kilometers downwind.The research conclusions provide a powerful scientific basis for optimizing design and operation,improving efficiency,minimizing the negative impacts on adjacent wind turbines,and ensuring the sustainable development of wind energy through dynamic planning and scientific assessment.
基金funded by University of Transport and Communications(UTC)under grant number T2025-CN-004.
文摘Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi-stego images provides good image quality but often results in low embedding capability.To address these challenges,this paper proposes a high-capacity RDH scheme based on PVO that generates three stego images from a single cover image.The cover image is partitioned into non-overlapping blocks with pixels sorted in ascending order.Four secret bits are embedded into each block’s maximum pixel value,while three additional bits are embedded into the second-largest value when the pixel difference exceeds a predefined threshold.A similar embedding strategy is also applied to the minimum side of the block,including the second-smallest pixel value.This design enables each block to embed up to 14 bits of secret data.Experimental results demonstrate that the proposed method achieves significantly higher embedding capacity and improved visual quality compared to existing triple-stego RDH approaches,advancing the field of reversible steganography.
文摘Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstanding performance across various domains,thereby prompting researchers to investigate their applicability in recommendation systems.However,due to the lack of task-specific knowledge and an inefficient feature extraction process,LLMs still have suboptimal performance in recommendation tasks.Therefore,external knowledge sources,such as knowledge graphs(KGs)and knowledge bases(KBs),are often introduced to address the issue of data sparsity.Compared to KGs,KBs possess higher retrieval efficiency,making them more suitable for scenarios where LLMs serve as recommenders.To this end,we introduce a novel framework integrating LLMs with KBs for enhanced retrieval generation,namely LLMKB.LLMKB initially leverages structured knowledge to create mapping dictionaries,extracting entity-relation information from heterogeneous knowledge to construct KBs.Then,LLMKB achieves the embedding calibration between user information representations and documents in KBs through retrieval model fine-tuning.Finally,LLMKB employs retrievalaugmented generation to produce recommendations based on fused text inputs,followed by post-processing.Experiment results on two public CRS datasets demonstrate the effectiveness of our framework.Our code is publicly available at the link:https://anonymous.4open.science/r/LLMKB-6FD0.
基金supported by the National Natural Science Foundation of China(22172086,22105117)the Taishan Scholars Program of Shandong Province(202103064)the Major Basic Research Project of Shandong Province(ZR2021ZD06)。
文摘Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performance indicators such as catalytic activity,selectivity,and stability can be effectively optimized.As a result,they become essential parameters that must be considered in the design and development of high-efficiency catalysts.This study proposes a surface engineering method to accurately control the concentration of surface LA and LB sites in defect-laden In_(2)O_(3-x)(OH)_(y)(denoted as N-n%-IO),establishing three types of LB/LA stoichiometric ratios with different photocatalytic CO_(2)hydrogenation performances.It is demonstrated that the LB-rich system(LB/LA>1)shows suppressed activity.In contrast,the balanced stoichiometric ratio system(LB/LA=1)attains an optimal methanol yield(179.79μmol g^(-1)h^(-1))and selectivity(43.67%),while the LA-rich system(LB/LA<1)exhibits the best CO production rate(1913.76μmol g^(-1)h^(-1))and selectivity(94.96%).Systematic experiments disclose that the balanced LB/LA system with adjacent surface frustrated Lewis pairs(SFLPs)can effectively facilitate the adsorption/activation of reactants,stabilize intermediates,and regulate the dynamic behavior of photo-generated carriers.However,the imbalanced LB/LA systems either lack necessary active sites or can only follow an oxygen vacancy-mediated pathway during photocatalytic CO_(2)hydrogenation.This work offers a comprehensive understanding of the crucial functions of surface Lewis acid/base sites in the product distribution of solar-driven CO_(2)reduction.
文摘Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,tau is not an easy target because it dynamically interacts with microtubules and other cellular components,which presents a challenge for tau-targeted drugs.New cellular models could aid the development of mechanism-based tau-targeted therapies.
文摘Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article has been corrected.
文摘Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work proposes Secured-FL,a blockchain-based defensive framework that combines smart contract-based authentication,clustering-driven outlier elimination,and dynamic threshold adjustment to defend against adversarial attacks.The framework was implemented on a private Ethereum network with a Proof-of-Authority consensus algorithm to ensure tamper-resistant and auditable model updates.Large-scale simulation on the Cyber Data dataset,under up to 50%malicious client settings,demonstrates Secured-FL achieves 6%-12%higher accuracy,9%-15%lower latency,and approximately 14%less computational expense compared to the PPSS benchmark framework.Additional tests,including confusion matrices,ROC and Precision-Recall curves,and ablation tests,confirm the interpretability and robustness of the defense.Tests for scalability also show consistent performance up to 500 clients,affirming appropriateness to reasonably large deployments.These results make Secured-FL a feasible,adversarially resilient FL paradigm with promising potential for application in smart cities,medicine,and other mission-critical IoT deployments.
文摘The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Surfaces",line 2:The device name was corrected from"YDFLP-E-50-M8"to"YDFLP-50-M8."Page 3,Section 2.4:The phrase"95%confidence interval"has been corrected to"95%confidence level."Page 3,Figure 1 caption:The phrase"fandg"has been corrected to"f and g."The order"C4 and C12"has been reversed to"C12 and C4,"in accordance with the display order in the figure.Page 4,Figure reference:The phrase"Figs.4c and d"has been corrected to"Figs.5b and c."Page 5,paragraph starting with"The ANOVA results are presented...":The phrase"95%confidence interval"has been corrected to"95%confidence level."
文摘Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursing allowances provided by the Chinese government for people with disabilities who are unable to work are not only important components of China’s social security system which provide for the needs of its disabled,but also show China’s ability to guarantee the basic living standard and social fairness and justice for this group of people.
基金supported by the National Natural Science Foundation of China(62473082,82202250,82121003,62036003,and 62333003)the Fundamental Research Funds for the Central Universities(ZYGX2022YGRH008 and ZYGX2024XJ054)the Medical-Engineering Cooperation Funds from the University of Electronic Science and Technology of China(ZYGX2021YGLH201).
文摘The brain atlas,or parcellation-delineating spatial partitions,organizes the brain's structure and function[1].The spatial arrangements of highly heterogeneous landscapes represent specialized functional regions for investigating their interactions.Early efforts to parcellate the mammalian brain,using histological cytoarchitecture and myeloarchitecture,as well as recent in vivo magnetic resonance imaging(MRl)[2,3],have primarily involved cortical areas,subcortical structures,and cerebellar nuclei.Human brain parcellations primarily focus on grey matter(GM),which purposefully excludes white matter(WM),hindering the development of next-generation brain atlases.
文摘In this paper, by msss_mappings, the relations between metric spaces and spaces with σ _locally countable cs_networks or spaces with σ _locally countable weak bases are established. These are some answers to Alexandroff’s problems.
文摘Based on the existing reports on the bioactive isatin derivatives, a number of Schiff bases were synthesized by reacting 5-substituted isatins with bioactive amines/hydrazides and their structures were confirmed using spectroscopic methods such as NMR, IR and mass spectrometry. Furthermore, Nbenzylation of isatin followed by the Schiff base formation furnished a new series of compounds(11a-13c) which allowed the analysis of the effect of isatin N-substitution on the bioactivity of the resulting compounds. The antibacterial activity of the synthesized derivatives was evaluated using a microtiter plate method on a series of gram positive and gram negative bacterial strains. Compounds 2d, 3b, 5c and 6a were among the most potent derivatives against Pseudomonas aeruginosa(MIC = 6.25 μg/m L).Analysis of the structure-activity relationship showed that the incorporation of(thio)urea-based Schiff bases lead to more potent derivatives with a broader spectrum of antibacterial activity. In addition,highly lipophilic compounds such as 11a-12c did not show any measurable antibacterial activity, which implies that an optimal lipophilicity might be an important requirement for the antibacterial activity of the studied isatins. Finally, the finding that hydantoin derivatives of N-benzylisatins(13a-13c) still exhibit some antibacterial activity prompted us to consider exploring the bioactivity of more diverse derivatives of isatin-aminohydantoin Schiff bases(compounds 1a-1d) in our future studies.
文摘Seven new Schiff bases, which are 4,4,4-trifluo-ro-1-(2-thienyl)-1-butanone-3-Z, Z =-thioseraicarbazone (a); -thiocarbohydrazone (b),-benzoic hydrazone (c), -( o-hydroxyphenyl) imine (d) ,-nicotinic hydrazone (e),-salicylic hydrazone (f), and -(p-fluoro-m-chlorophenyl) imine (g), have been synthesized by reaction of 4, 4, 4-trifluoro-1-(2-thienyl)-1,3-butanedione (TFTBD) with corresponding hy-drazides or anilines, acetic acid or p-toluence sulfonic acid as catalyst, and characterized by Elemental analysis, IR, UV-Vis,1H NMR and MS. The MS spectra confirmed that the -C3=O condensed with primary amino group. Tauto-merism of the compounds is discussed.
基金Under the auspices of National Natural Science Foundation of China(No.41571152,41771179).
文摘The economic transformation of the old industrial bases is a key research topic among geographers in China.In this paper,we propose that the concept of regional economic resilience(RER)has unique theoretical value in analyzing the economic transformation of the old industrial bases.We constructed an analytical framework and an index system and applied the conceptual tools to study the evolution of RER in the old industrial base of Liaoning Province in China,which is currently subjected to not only sudden shocks but‘slow burn’—longer term processes of change that may nevertheless affect the regional economy.There are four main findings:first,the evolution of RER in Liaoning can be divided into four stages from 2000 to 2015.Liaoning is currently in its conservation-release period,and the next stage will be a release-reorganization period.Second,the RER of the majority of the studied cities is lower than the average value for Liaoning,and this is mainly attributed to the relatively weak vulnerability-resistance and adaptability-transformation capacity of these cities.Third,the RER levels of the 14 cities in Liaoning differ significantly.At the first level is Shenyang and Dalian,at the second level is Dandong and Yingkou,and the third level comprises the remaining cities.Fourth,regional economic resilience is mainly determined by vulnerability-resistance,which indirectly reflects Liaoning’s lack of adaptability-transformation capacity,and the ability of the region to renew or create a new development path is weak.