Throughout the 20th century, several large megathrust earthquakes were observed in the Colombia–Ecuador subduction zone which widely ruptured plate interfaces, causing considerable damage and loss of life. The occurr...Throughout the 20th century, several large megathrust earthquakes were observed in the Colombia–Ecuador subduction zone which widely ruptured plate interfaces, causing considerable damage and loss of life. The occurrence of earthquakes in subduction zones is thought to be closely related to the thermal structure of the incoming plate. However, in the case of the subducting Nazca Plate beneath the Colombia–Ecuador zone, the thermal structure remains unclear, especially its hydraulic distribution. On the basis of 3D thermal models, we present new insights into the plate interface conditions of Colombia–Ecuador interplate and megathrust earthquakes. We show that the plate geometry strongly affects the along-strike thermal structure of the slab beneath Colombia and Ecuador, with the subduction of the Carnegie Ridge playing an important role. Our results further reveal that the unique geometry of the Nazca Plate is the primary reason for the relatively high temperatures of the slab beneath Colombia. We suggest that the positions of the100–200 ℃ and 350–450 ℃ isotherms on the plate interface determine the updip and downdip limits of the seismogenic zone. For Colombia–Ecuador interplate earthquakes, the released fluids control the distribution of shallow-depth earthquakes, whereas the age and geometry of the slab control the distribution of intermediate-depth earthquakes. The average temperature of the plate interface at the upper limit of large megathrust earthquakes is hotter than previously thought, which is more consistent with our understanding of the Colombia–Ecuador subduction zone. We predict that the potential location of future large seismic events could be in the rupture zone of past seismic events or offshore of northern Colombia.展开更多
The dependence of the subduction regime on three-dimensional slab geometry poses a challenge for accurately estimating the evolving thermal structure of megathrusts globally. Although slab dips and ages have gained at...The dependence of the subduction regime on three-dimensional slab geometry poses a challenge for accurately estimating the evolving thermal structure of megathrusts globally. Although slab dips and ages have gained attention, the specific impacts of oblique subduction remain unmeasured. Here, we present an integrated thermal model that quantifies how slab morphology can shape the thermal state of megathrusts, such as those in the Makran Subduction Zone. The model considers both slab obliquity and depth variations along the trench. We find a considerable match between the slab petrological dehydration zone and the distribution of great crustal earthquakes. We suggest that the accumulation of fluids along megathrusts by slab metamorphism can foster more polarized conditions for decreasing plate coupling and increasing interplate ruptures. It is thus imperative to improve model representation and more realistically represent how drivers of slab geometry affect metamorphic transitions and the occurrence of earthquakes at megathrusts.展开更多
Objective Heat wave exposure significantly impacts human health.Nevertheless,studies on the long-term effects of heat wave exposure during adolescence on adverse pregnancy outcomes(APOs)are rare.This study aimed to in...Objective Heat wave exposure significantly impacts human health.Nevertheless,studies on the long-term effects of heat wave exposure during adolescence on adverse pregnancy outcomes(APOs)are rare.This study aimed to investigate the relationship between the long-term effects of heat wave exposure during adolescence and APOs.Methods We analyzed data from 3,376 female and 3,013 male participants across 31 provinces in China.All adolescents(10–19 years old),early adolescents(10–14),and late adolescents(15–19)were chosen as exposure windows.Heat waves were defined as periods lasting 2‒4 consecutive days with the daily temperature exceeding the 75th,90th,and 92.5th percentiles.We employed multivariate logistic regression models to assess the associations between exposure to heat waves during adolescence and APOs.Results The results revealed significant associations between male exposure to heat wave events during late adolescence and spontaneous abortion(P<0.05),which was more pronounced in South China.In contrast,no statistically significant associations were detected between males’exposure to heat wave events during adolescence and their partners’preterm birth(P>0.05 for all comparisons).The exposure of females to heat waves during adolescence was not significantly associated with subsequent spontaneous abortion or preterm birth(P>0.05 for all comparisons).Conclusions This study demonstrates that spontaneous abortion in females is associated with heat wave exposure in their male partner during adolescence.展开更多
To explore the spontaneous magnetization of iron-bearing rare earth ores during suspension roasting,binary minerals containing hematite and bastnaesite were used to investigate the effects of the roasting temperature,...To explore the spontaneous magnetization of iron-bearing rare earth ores during suspension roasting,binary minerals containing hematite and bastnaesite were used to investigate the effects of the roasting temperature,roasting time,and bastnaesite-to-hematite mass ratio on in-situ reduction of hematite in a N_(2)atmosphere.Relevant analytical tests were used to explore the mineral phase evolution during roasting,the magnetism and microstructure of the roasted products,the phase composition,and the surface element valence of concentrate.It was found that magnetic separation of the iron concentrate afforded an iron grade of 68.87%and a recovery of 93.18%under the optimum roasting conditions.During roasting,bastnaesite decomposed to generate CO_(2)and CO,and the compact structure of hematite was gradually destroyed,resulting in microcracks.Subsequently,the CO entered the surface of the hematite through the microcracks and reacted to form a magnetite shell,and the magnetite-encapsulated hematite particles were recovered via low-intensity magnetic separation.展开更多
With the widespread implementation of distributed generation(DG)and the integration of soft open point(SOP)into the distribution network(DN),the latter is steadily transitioning into a flexible distribution network(FD...With the widespread implementation of distributed generation(DG)and the integration of soft open point(SOP)into the distribution network(DN),the latter is steadily transitioning into a flexible distribution network(FDN),the calculation of carbon flow distribution in FDN is more difficult.To this end,this study constructs a model for low-carbon optimal operations within the FDN on the basis of enhanced carbon emission flow(CEF).First,the carbon emission characteristics of FDNs are scrutinized and an improved method for calculating carbon flow within these networks is proposed.Subsequently,a model for optimizing low-carbon operations within FDNs is formulated based on the refined CEF,which merges the specificities of DG and intelligent SOP.Finally,this model is scrutinized using an upgraded IEEE 33-node distribution system,a comparative analysis of the cases reveals that when DG and SOP are operated in a coordinated manner in the FDN,with the cost of electricity generation was reduced by 40.63 percent and the cost of carbon emissions by 10.18 percent.The findings indicate that the judicious optimization of areas exhibiting higher carbon flow rates can effectively enhance the economic efficiency of DN operations and curtail the carbon emissions of the overall network.展开更多
Objective The effects of prolonged exposure to persistently elevated atmospheric pollutants,commonly termed air pollution waves,on fertility intentions remain inadequately understood.This study aims to investigate the...Objective The effects of prolonged exposure to persistently elevated atmospheric pollutants,commonly termed air pollution waves,on fertility intentions remain inadequately understood.This study aims to investigate the association between particulate matter(PM)exposure and fertility intentions.Methods In this nationwide cross-sectional study,we analyzed data from 10,747 participants(5496 females and 5251 males).PM waves were defined as periods lasting 3‒6 consecutive days during which the daily average concentrations exceeded China’s Ambient Air Quality Standards Grade II thresholds(PM2.5>75μg/m3 and PM10>150μg/m3).We employed multivariate logistic regression models to assess the association between exposure to PM waves and fertility intentions.Results Significant inverse associations were detected between exposure to PM2.5 wave events(characterized by concentrations exceeding 75μg/m3 for durations of 4‒6 days,P<0.05)and PM10 wave events(defined as concentrations exceeding 150μg/m3 for 6 consecutive days,P<0.05)and fertility intentions among females.In contrast,neither the PM2.5 wave nor the PM10 wave events demonstrated statistically significant correlations with fertility intentions in males(P>0.05 for all comparisons).The potentially susceptible subgroup was identified as females aged 20–30 years.Conclusions Our results provide the first evidence that PM2.5 and PM10 waves are associated with a reduction in female fertility intentions,offering critical insights for the development of public health policies and strategies aimed at individual protection.展开更多
Inspired by structures of antenna-reaction centers in photosynthesis, the complex micelle was prepared from zinc tetra-phenyl porphyrin （ZnTPP）, fullerene derivative （PyC60） and poly（ethylene glycol）-block-poly...Inspired by structures of antenna-reaction centers in photosynthesis, the complex micelle was prepared from zinc tetra-phenyl porphyrin （ZnTPP）, fullerene derivative （PyC60） and poly（ethylene glycol）-block-poly（E-caprolactone） （PEG-b- PCL）. The core-shell structure made the hydrophobic donor-acceptor system work in aqueous. In micellar core, coordination interaction occurred between ZnTPP and PyC60 molecules which ensured the enhanced energy migration from the donor to the acceptor. The enhanced interaction between porphyrin and fullerene was confirmed by absorption, steady-state fluorescence and transient fluorescence. The generation of singlet oxygen and superoxide radical was detected by iodide method and reduction of nitro blue tetrazolium, respectively, which confirmed that electron transfer reaction in the complex micellar core occurred. Moreover, the complex micelle exhibited effective electron transfer performance in photodebromination of 2,3-dibromo-3-phenylpropionic acid. The complex micellar structure endowed the donor-acceptor system with improved stability under irradiation. This strategy could be helpful for designing new electron transfer platform and artificial photosynthetic system.展开更多
This study investigates the necessity for space robots to independently exchange their end-effectors due to the contradiction that exists between the requirements of various robots in space missions and the payload ca...This study investigates the necessity for space robots to independently exchange their end-effectors due to the contradiction that exists between the requirements of various robots in space missions and the payload capacity limits of rockets. The results of this study summarize the system requirements for a new end-effector exchange mechanism, including compact size, misalignment tolerance, and regolith tolerance. This is followed by the development of a prototype model with a set of test apparatus. Then the function of the prototype is verified, the prototype is optimized, and the relation between docking force and misalignment is examined through operation tests.展开更多
This study investigated the interaction between the furfural residue and polyvinyl chloride co-pyrolysis using an infrared heating method.Various analytical techniques including production distribution analysis,therma...This study investigated the interaction between the furfural residue and polyvinyl chloride co-pyrolysis using an infrared heating method.Various analytical techniques including production distribution analysis,thermal behavior,pyrolysis kinetic,simulated distillation and gas chromatography-mass spectrography(GCMS),and X-ray photoelectron spectroscopy were utilized to elucidate the pyrolysis characterization and reaction mechanism during the co-pyrolysis.Initially,the yield of co-pyrolysis oil increased from 35.12%at 5℃·s^(–1)to 37.70%at 10℃·s^(-1),but then decreased to 32.07%at 20℃·s^(-1).Kinetic and thermodynamic parameters suggested non-spontaneous and endothermic behaviors.GCMS analysis revealed that aromatic hydrocarbons,especially mono-and bi-cyclic ones,are the predominant compounds in the oil due to the presence of H radicals in polyvinyl chloride,suggesting an enhancement in oil quality.Meanwhile,the fixed chlorine content increased to 65.11%after co-pyrolysis due to the interaction between inorganic salts in furfural residues and chlorine from polyvinyl chloride.展开更多
Phototherapy,including photodynamic therapy(PDT)and photothermal therapy(PTT),that employs phototherapeutic agents to generate cytotoxic reactive oxygen species(ROS)or hyperthermia,is a promising approach for disease ...Phototherapy,including photodynamic therapy(PDT)and photothermal therapy(PTT),that employs phototherapeutic agents to generate cytotoxic reactive oxygen species(ROS)or hyperthermia,is a promising approach for disease therapy.However,conventional organic phototherapeutic agents suffer poor photostability and aggregation-caused quenching(ACQ)in the aggregate state,restricting their therapeutic efficacy.Aggregation-induced emission(AIE)agents can solve these issues with strong emission in the aggregate state and reverse designation to generate heat.This review summarizes the recent advances in the development of AIE phototherapy agents for enhanced PDT and PTT performances in biomedical applications.First,design strategies of AIE agents that adjust the intersystem crossing process or intramolecular charge transfer to boost ROS generation or regulate ROS types are discussed.The AIE agents with ROS generation ability for biomedical applications including antitumor and antibacterial performances are then introduced.Next,designs and examples of AIE agents that enhance PTT performances through molecular motions are described.Finally,the current challenges and perspectives of AIE agents in the phototherapy field are discussed.展开更多
A complex micelle as a hemoglobin functional model with the biaoactive function of reversible oxygen transfer has been constructed through the hierarchical assembly of the diblock copolymer poly（ethylene glycol）-blo...A complex micelle as a hemoglobin functional model with the biaoactive function of reversible oxygen transfer has been constructed through the hierarchical assembly of the diblock copolymer poly（ethylene glycol）-block- poly（4-vinylpyridine-co-N-heptyl-4-vinylpyridine） （PEG-b-P（4VP-co-4VPHep））, tetrakis（4-sulfonatophenyl）porphinato iron（II） （Fe（II）TPPS） and β-cyclodextrin （β-CD）. The μ-oxo dimer of Fe（II）TPPS was successfully inhibited because the Fe（II）TPPS was included into the cavities of β-CDs through host-vip interaction. Fe（II）TPPS coordinated with pyridine groups functions as the active site to reversibly bind dioxygen. In adition, the host-vip inclusion （β-CD/Fe（II）TPPS） was encapsulated in the hydrophobic core of the complex micelle and tightly fixed by P4VP chains. The hydrophilic PEG blocks stretched in aqueous solution to constitute the shells which stabilize the structure of the complex micelle as well as endow the complex micelle with sufficient blood circulation time. Dioxygen can be bound to the Fe（II）TPPS located in the confined space and excellent reversibility of the binding-release process of dioxygen can be achieved. The quaternary amine N-heptyl-4-vinylpyridine can coerce abundant S2O4^2- ions into the core of the complex micelle to facilitate the self-reduction process. Dioxygen adducts （Fe（II）TPPS（O2）） were effectively protected by the double hydrophobic barriers constructed by the cavity of the cyclodextrin and the core of the complex micelle which enhances the ability to resist nucleophilic molecules. Therefore, the rationally designed amphiphilic structure can work as a promising artificial O2 carrier. Potentially, the complex micelle can be expected to improve the treatment of diseases linked with hypoxia.展开更多
基金benefited from the financial support of the CAS Pioneer Hundred Talents Program and the Second Tibetan Plateau Scientific Expedition and Research Program (2019QZKK0708)。
文摘Throughout the 20th century, several large megathrust earthquakes were observed in the Colombia–Ecuador subduction zone which widely ruptured plate interfaces, causing considerable damage and loss of life. The occurrence of earthquakes in subduction zones is thought to be closely related to the thermal structure of the incoming plate. However, in the case of the subducting Nazca Plate beneath the Colombia–Ecuador zone, the thermal structure remains unclear, especially its hydraulic distribution. On the basis of 3D thermal models, we present new insights into the plate interface conditions of Colombia–Ecuador interplate and megathrust earthquakes. We show that the plate geometry strongly affects the along-strike thermal structure of the slab beneath Colombia and Ecuador, with the subduction of the Carnegie Ridge playing an important role. Our results further reveal that the unique geometry of the Nazca Plate is the primary reason for the relatively high temperatures of the slab beneath Colombia. We suggest that the positions of the100–200 ℃ and 350–450 ℃ isotherms on the plate interface determine the updip and downdip limits of the seismogenic zone. For Colombia–Ecuador interplate earthquakes, the released fluids control the distribution of shallow-depth earthquakes, whereas the age and geometry of the slab control the distribution of intermediate-depth earthquakes. The average temperature of the plate interface at the upper limit of large megathrust earthquakes is hotter than previously thought, which is more consistent with our understanding of the Colombia–Ecuador subduction zone. We predict that the potential location of future large seismic events could be in the rupture zone of past seismic events or offshore of northern Colombia.
基金benefited from the financial support of the Chinese Academy of Sciences Pioneer Hundred Talents Programthe Second Tibetan Plateau Scientific Expedition and Research Program (Grant No. 2019QZKK0708)+2 种基金the MEXT KAKENHI grant (Grant No. 21H05203)the Kobe University Strategic International Collaborative Research Grant (Type B Fostering Joint Research)the “Science of Slowto-Fast Earthquakes” project。
文摘The dependence of the subduction regime on three-dimensional slab geometry poses a challenge for accurately estimating the evolving thermal structure of megathrusts globally. Although slab dips and ages have gained attention, the specific impacts of oblique subduction remain unmeasured. Here, we present an integrated thermal model that quantifies how slab morphology can shape the thermal state of megathrusts, such as those in the Makran Subduction Zone. The model considers both slab obliquity and depth variations along the trench. We find a considerable match between the slab petrological dehydration zone and the distribution of great crustal earthquakes. We suggest that the accumulation of fluids along megathrusts by slab metamorphism can foster more polarized conditions for decreasing plate coupling and increasing interplate ruptures. It is thus imperative to improve model representation and more realistically represent how drivers of slab geometry affect metamorphic transitions and the occurrence of earthquakes at megathrusts.
基金funded by the Key Project of the University Outstanding Youth Backbone Talented Person Foreign Visits Study Does Research of Anhui Province(No.gxgwfx2020025).
文摘Objective Heat wave exposure significantly impacts human health.Nevertheless,studies on the long-term effects of heat wave exposure during adolescence on adverse pregnancy outcomes(APOs)are rare.This study aimed to investigate the relationship between the long-term effects of heat wave exposure during adolescence and APOs.Methods We analyzed data from 3,376 female and 3,013 male participants across 31 provinces in China.All adolescents(10–19 years old),early adolescents(10–14),and late adolescents(15–19)were chosen as exposure windows.Heat waves were defined as periods lasting 2‒4 consecutive days with the daily temperature exceeding the 75th,90th,and 92.5th percentiles.We employed multivariate logistic regression models to assess the associations between exposure to heat waves during adolescence and APOs.Results The results revealed significant associations between male exposure to heat wave events during late adolescence and spontaneous abortion(P<0.05),which was more pronounced in South China.In contrast,no statistically significant associations were detected between males’exposure to heat wave events during adolescence and their partners’preterm birth(P>0.05 for all comparisons).The exposure of females to heat waves during adolescence was not significantly associated with subsequent spontaneous abortion or preterm birth(P>0.05 for all comparisons).Conclusions This study demonstrates that spontaneous abortion in females is associated with heat wave exposure in their male partner during adolescence.
基金the financial support from the National Key R&D Program of China(No.2022YFC2905800)the National Natural Science Foundation of China(Nos.52174242,52130406)。
文摘To explore the spontaneous magnetization of iron-bearing rare earth ores during suspension roasting,binary minerals containing hematite and bastnaesite were used to investigate the effects of the roasting temperature,roasting time,and bastnaesite-to-hematite mass ratio on in-situ reduction of hematite in a N_(2)atmosphere.Relevant analytical tests were used to explore the mineral phase evolution during roasting,the magnetism and microstructure of the roasted products,the phase composition,and the surface element valence of concentrate.It was found that magnetic separation of the iron concentrate afforded an iron grade of 68.87%and a recovery of 93.18%under the optimum roasting conditions.During roasting,bastnaesite decomposed to generate CO_(2)and CO,and the compact structure of hematite was gradually destroyed,resulting in microcracks.Subsequently,the CO entered the surface of the hematite through the microcracks and reacted to form a magnetite shell,and the magnetite-encapsulated hematite particles were recovered via low-intensity magnetic separation.
基金supported in part by National Natural Science Foundation of China under Grant 52007026.
文摘With the widespread implementation of distributed generation(DG)and the integration of soft open point(SOP)into the distribution network(DN),the latter is steadily transitioning into a flexible distribution network(FDN),the calculation of carbon flow distribution in FDN is more difficult.To this end,this study constructs a model for low-carbon optimal operations within the FDN on the basis of enhanced carbon emission flow(CEF).First,the carbon emission characteristics of FDNs are scrutinized and an improved method for calculating carbon flow within these networks is proposed.Subsequently,a model for optimizing low-carbon operations within FDNs is formulated based on the refined CEF,which merges the specificities of DG and intelligent SOP.Finally,this model is scrutinized using an upgraded IEEE 33-node distribution system,a comparative analysis of the cases reveals that when DG and SOP are operated in a coordinated manner in the FDN,with the cost of electricity generation was reduced by 40.63 percent and the cost of carbon emissions by 10.18 percent.The findings indicate that the judicious optimization of areas exhibiting higher carbon flow rates can effectively enhance the economic efficiency of DN operations and curtail the carbon emissions of the overall network.
基金supported by grants from the National Key Research and Development Program of China(No.2023YFC2705700)Guangdong Basic and Applied Basic Research Foundation(No.2024A1515012355)+1 种基金the Shenzhen Science and Technology Program(No.JCYJ20220530140609020)the Scientific Research Project of Wuhan Municipal Health Commission(No.WX21Q36).
文摘Objective The effects of prolonged exposure to persistently elevated atmospheric pollutants,commonly termed air pollution waves,on fertility intentions remain inadequately understood.This study aims to investigate the association between particulate matter(PM)exposure and fertility intentions.Methods In this nationwide cross-sectional study,we analyzed data from 10,747 participants(5496 females and 5251 males).PM waves were defined as periods lasting 3‒6 consecutive days during which the daily average concentrations exceeded China’s Ambient Air Quality Standards Grade II thresholds(PM2.5>75μg/m3 and PM10>150μg/m3).We employed multivariate logistic regression models to assess the association between exposure to PM waves and fertility intentions.Results Significant inverse associations were detected between exposure to PM2.5 wave events(characterized by concentrations exceeding 75μg/m3 for durations of 4‒6 days,P<0.05)and PM10 wave events(defined as concentrations exceeding 150μg/m3 for 6 consecutive days,P<0.05)and fertility intentions among females.In contrast,neither the PM2.5 wave nor the PM10 wave events demonstrated statistically significant correlations with fertility intentions in males(P>0.05 for all comparisons).The potentially susceptible subgroup was identified as females aged 20–30 years.Conclusions Our results provide the first evidence that PM2.5 and PM10 waves are associated with a reduction in female fertility intentions,offering critical insights for the development of public health policies and strategies aimed at individual protection.
基金financially supported by the National Natural Science Foundation of China(Nos.91527306,51390483,21620102005,51603231 and 51503104)the Natural Science Foundation of Tianjin(Nos.16JCQNJC02500 and16JCQNJC03000)
文摘Inspired by structures of antenna-reaction centers in photosynthesis, the complex micelle was prepared from zinc tetra-phenyl porphyrin （ZnTPP）, fullerene derivative （PyC60） and poly（ethylene glycol）-block-poly（E-caprolactone） （PEG-b- PCL）. The core-shell structure made the hydrophobic donor-acceptor system work in aqueous. In micellar core, coordination interaction occurred between ZnTPP and PyC60 molecules which ensured the enhanced energy migration from the donor to the acceptor. The enhanced interaction between porphyrin and fullerene was confirmed by absorption, steady-state fluorescence and transient fluorescence. The generation of singlet oxygen and superoxide radical was detected by iodide method and reduction of nitro blue tetrazolium, respectively, which confirmed that electron transfer reaction in the complex micellar core occurred. Moreover, the complex micelle exhibited effective electron transfer performance in photodebromination of 2,3-dibromo-3-phenylpropionic acid. The complex micellar structure endowed the donor-acceptor system with improved stability under irradiation. This strategy could be helpful for designing new electron transfer platform and artificial photosynthetic system.
文摘This study investigates the necessity for space robots to independently exchange their end-effectors due to the contradiction that exists between the requirements of various robots in space missions and the payload capacity limits of rockets. The results of this study summarize the system requirements for a new end-effector exchange mechanism, including compact size, misalignment tolerance, and regolith tolerance. This is followed by the development of a prototype model with a set of test apparatus. Then the function of the prototype is verified, the prototype is optimized, and the relation between docking force and misalignment is examined through operation tests.
基金This research was supported by the National Natural Science Foundation of China(Grant Nos.52104245 and 22178123)the National Natural Science Foundation of Chongqing(Grant Nos.cstc2021jcyj-msxmX0099,2021XM3073,and 2019LY41).
文摘This study investigated the interaction between the furfural residue and polyvinyl chloride co-pyrolysis using an infrared heating method.Various analytical techniques including production distribution analysis,thermal behavior,pyrolysis kinetic,simulated distillation and gas chromatography-mass spectrography(GCMS),and X-ray photoelectron spectroscopy were utilized to elucidate the pyrolysis characterization and reaction mechanism during the co-pyrolysis.Initially,the yield of co-pyrolysis oil increased from 35.12%at 5℃·s^(–1)to 37.70%at 10℃·s^(-1),but then decreased to 32.07%at 20℃·s^(-1).Kinetic and thermodynamic parameters suggested non-spontaneous and endothermic behaviors.GCMS analysis revealed that aromatic hydrocarbons,especially mono-and bi-cyclic ones,are the predominant compounds in the oil due to the presence of H radicals in polyvinyl chloride,suggesting an enhancement in oil quality.Meanwhile,the fixed chlorine content increased to 65.11%after co-pyrolysis due to the interaction between inorganic salts in furfural residues and chlorine from polyvinyl chloride.
基金supported by the National Key R&D Program of China(nos.2017YFA0701301 and 2017YFA 0205400)National Natural Science Foundation of China(nos.51690153,21720102005,and 51903120)the Fundamental Research Funds for the Central Universities(no.020514913212).
文摘Phototherapy,including photodynamic therapy(PDT)and photothermal therapy(PTT),that employs phototherapeutic agents to generate cytotoxic reactive oxygen species(ROS)or hyperthermia,is a promising approach for disease therapy.However,conventional organic phototherapeutic agents suffer poor photostability and aggregation-caused quenching(ACQ)in the aggregate state,restricting their therapeutic efficacy.Aggregation-induced emission(AIE)agents can solve these issues with strong emission in the aggregate state and reverse designation to generate heat.This review summarizes the recent advances in the development of AIE phototherapy agents for enhanced PDT and PTT performances in biomedical applications.First,design strategies of AIE agents that adjust the intersystem crossing process or intramolecular charge transfer to boost ROS generation or regulate ROS types are discussed.The AIE agents with ROS generation ability for biomedical applications including antitumor and antibacterial performances are then introduced.Next,designs and examples of AIE agents that enhance PTT performances through molecular motions are described.Finally,the current challenges and perspectives of AIE agents in the phototherapy field are discussed.
文摘A complex micelle as a hemoglobin functional model with the biaoactive function of reversible oxygen transfer has been constructed through the hierarchical assembly of the diblock copolymer poly（ethylene glycol）-block- poly（4-vinylpyridine-co-N-heptyl-4-vinylpyridine） （PEG-b-P（4VP-co-4VPHep））, tetrakis（4-sulfonatophenyl）porphinato iron（II） （Fe（II）TPPS） and β-cyclodextrin （β-CD）. The μ-oxo dimer of Fe（II）TPPS was successfully inhibited because the Fe（II）TPPS was included into the cavities of β-CDs through host-vip interaction. Fe（II）TPPS coordinated with pyridine groups functions as the active site to reversibly bind dioxygen. In adition, the host-vip inclusion （β-CD/Fe（II）TPPS） was encapsulated in the hydrophobic core of the complex micelle and tightly fixed by P4VP chains. The hydrophilic PEG blocks stretched in aqueous solution to constitute the shells which stabilize the structure of the complex micelle as well as endow the complex micelle with sufficient blood circulation time. Dioxygen can be bound to the Fe（II）TPPS located in the confined space and excellent reversibility of the binding-release process of dioxygen can be achieved. The quaternary amine N-heptyl-4-vinylpyridine can coerce abundant S2O4^2- ions into the core of the complex micelle to facilitate the self-reduction process. Dioxygen adducts （Fe（II）TPPS（O2）） were effectively protected by the double hydrophobic barriers constructed by the cavity of the cyclodextrin and the core of the complex micelle which enhances the ability to resist nucleophilic molecules. Therefore, the rationally designed amphiphilic structure can work as a promising artificial O2 carrier. Potentially, the complex micelle can be expected to improve the treatment of diseases linked with hypoxia.
