Traumatic spinal cord injury(SCI)is a debilitating condition characterized by the impairment of neural circuits,leading to the loss of motor and sensory functions and accompanied by severe complications.Substantial re...Traumatic spinal cord injury(SCI)is a debilitating condition characterized by the impairment of neural circuits,leading to the loss of motor and sensory functions and accompanied by severe complications.Substantial research has reported the therapeutic potential of Omega-3 fatty acids for the central nervous system,particularly after traumatic SCI.Omega-3 fatty acids may contribute to improving SCI recovery through their anti-inflammatory,anti-oxidative,neurotrophic,and membrane integrity-preserving properties.These functions of Omega-3 fatty acids are primarily mediated via the activation of G protein-coupled receptor 120(GPR120),commonly known as the fish oil-specific receptor.Advancements in understanding of the molecular mechanisms of GPR120’s recognition of Omega-3 fatty acids and its downstream signaling mechanisms has significantly promoted research on the pharmacological potential of Omega-3 fatty acids and the development of highly selective and high-affinity alternatives.This review aims to provide in-depth analysis of the comprehensive therapeutic potential of Omega-3 fatty acids for SCI and its accompanying complications,and the prospects for developing novel drugs based on the recognition of Omega-3 fatty acids by GPR120.展开更多
Developing non-conjugated luminescent polymers(NCLPs)with fluorescence and long-lived roomtemperature phosphorescence is of great significance for revealing the essence of NCLPs luminescence,which has gradually attrac...Developing non-conjugated luminescent polymers(NCLPs)with fluorescence and long-lived roomtemperature phosphorescence is of great significance for revealing the essence of NCLPs luminescence,which has gradually attracted the attention of researchers in recent years.Herein,polymethylol(PMO)and poly(3-butene-1,2-diol)(PBD)with polyhydroxy structures were prepared and their luminescence behaviors were investigated to reveal the clusteroluminescence(CL)mechanism.Compared with polyvinyl alcohol with non-luminescent behavior,PMO and PBD exhibit cyan-blue fluorescence with quantum yields of ca.12%and green room-temperature phosphorescence with lifetimes of ca.89 ms in the solid state.Both fluorescence and phosphorescence exhibit typical excitation-dependent CL behavior.Experimental and theoretical analyses show that the strong hydrogen-bonding interaction of PMO and PBD greatly promotes the formation of oxygen clusters and the through-space n-n interaction of oxygen atoms,enabling fluorescence and phosphorescence emission.Our results have enormous implications for understanding the CL mechanism of NCLPs and provide a new polymer design strategy for the rational design of novel NCLPs materials.展开更多
AIM:To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori(H.pylori) treatment in children with H.pylori-associated functional dyspepsia.METHODS:Children with H.pylori-associated f...AIM:To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori(H.pylori) treatment in children with H.pylori-associated functional dyspepsia.METHODS:Children with H.pylori-associated functional dyspepsia were enrolled in this study.H.pylori infection was confirmed by positive bacterial culture results.All of the children received triple H.pylori eradication therapy(a 2 wk course of omeprazole,amoxicillin,and clarithromycin).The children were divided into two groups based on the success of the H.pylori treatment:group 1(eradicated)-patients who had a negative 13C-urea breath test 2 mo after the end of therapy;and group 2(non-eradicated)-patients who had a positive 13C-urea breath test.Plasma ghrelin,gastric ghrelin mRNA,and the body mass index were evaluated in both groups before and after the H.pylori treatment.The plasma ghrelin levels were measured by a radioimmunoassay.The expression of gastric ghrelin mRNA was determined by real-time reverse transcription polymerase chain reaction.RESULTS:A total of 50 children with H.pylori-associated functional dyspepsia were treated with triple H.pylori eradication therapy.The mean age of the children was 5.52 ± 0.83 years,and there were 28 males and 22 females.Among the 50 H.pylori-positive children,30 successfully achieved eradication,and 20 did not.The mean plasma ghrelin levels of group 1 were 22.17 ± 1.73 ng/L and 26.59 ± 2.05 ng/L before and after the treatment,respectively,which was a significant increase(P = 0.001).However,the mean plasma ghrelin level of group 2 before and after the H.pylori treatment was 21.34 ± 2.40 ng/L and 22.24 ± 2.10 ng/L(P = 0.785).The plasma ghrelin levels increased substantially after treatment in group 1 but showed only minor changes in group 2.Similarly,the gastric ghrelin mRNA expression in group 1 before treatment was 2.84 ± 0.08.After treatment,the level was 3.11 ± 0.65,which was significantly different(P = 0.023).The gastric ghrelin mRNA expression in group 2 did not change significantly during the treatment(2.82 ± 0.44 vs 2.79 ± 0.31,P = 0.875).The plasma ghrelin and gastric ghrelin mRNA levels in group 1 increased substantially after the treatment but did not do so in group 2.In addition,the body mass index the two groups did not differ significantly 2 mo before and after the H.pylori treatment.CONCLUSION:H.pylori eradication increases the plasma and tissue ghrelin levels in children with H.pylori-associated functional dyspepsia.展开更多
Clusteroluminescence(CL)materials,as an emerging class of luminescent materials with unique photophysical properties,have received increasing attention owing to their great theoretical significance and potential for b...Clusteroluminescence(CL)materials,as an emerging class of luminescent materials with unique photophysical properties,have received increasing attention owing to their great theoretical significance and potential for biological applications.Although much progress has been made in the design,synthesis and application of CL materials,there is still a big challenge in the emission mechanism.So far,throughspace interaction has been proposed as the preliminary mechanism of the corresponding clusterizationtriggered emission(CTE)effect,but a systematic theory is still needed.This review summarizes the current mechanistic understanding of CL materials including organic/inorganic small molecules,and polymers with/without isolated aromatic structures.In addition,some strategies to achieve high quantum yield,adjustable emission color,and persistent room temperature phosphorescence in CL materials are also summarized.At last,a perspective of the mechanism and application of CL materials are demonstrated,which inspire the researchers working on the development of new kinds of functional materials.展开更多
The aircraft industry is crucial to the economy and security of a nation.In this paper,the spatial characteristics and patterns of the aircraft industry are analyzed on different spatial scales.It is found that there ...The aircraft industry is crucial to the economy and security of a nation.In this paper,the spatial characteristics and patterns of the aircraft industry are analyzed on different spatial scales.It is found that there is a’Matthew effect’in the global aircraft industry and the spatial evolution of the industry is consistent with the industrialization process of the whole country.It is also revealed that the spatial evolution of the country is driven by both the centripetal forces including capital,talents,technology and agglomeration economies and the centrifugal forces including the comparative advantage,cost&risk sharing,emerging markets,development policy for less-developed regions and the military imperative.These forces have both market-stabilizing and market-disrupting effects on the spatial evolution of the aircraft industry.The study suggests that lessons drawn from the experiences in the United States and France are expected to be conducive to the rise of China’s aircraft industry in the future.展开更多
Clusteroluminogens(CLgens),nonconjugated structures with visible luminescence at the clustering state,have recently received remarkable attention due to their great theoretical significance and practical values.In car...Clusteroluminogens(CLgens),nonconjugated structures with visible luminescence at the clustering state,have recently received remarkable attention due to their great theoretical significance and practical values.In carbonyl-based aliphatic polymers,(n,π*)transition of carbonyl groups and the through-space interactions have been demonstrated to play an important role in their clusteroluminescence(CL)properties,but it is still a big challenge to manipulate their CL at the molecular level.In this work,six nonconjugated carbonyl-based polymers with different heteroatoms and steric hindrances were synthesized,and their photophysical properties were systematically studied.These polymers all showed CL but with different emission efficiency and wavelength.Experimental and theoretical studies indicated that the CL properties could be manipulated by changing the electronic structures of carbonyl groups and the rigidity of polymer chains.This work not only gains further insights into the CL mechanism but also provides reliable strategies to design and manipulate non-conjugated luminescent materials.展开更多
Embryo implantation is a crucial step in mammalian reproduction.However,little is known regarding the physiological roles of microRNAs in the regulation of embryo implantation.Here we show that a minimum uterine expre...Embryo implantation is a crucial step in mammalian reproduction.However,little is known regarding the physiological roles of microRNAs in the regulation of embryo implantation.Here we show that a minimum uterine expression of miR-181 is essential for the onset of embryo implantation.Both transient and prolonged transgenic expression of miR-181 led to impaired implantation,which can be rescued by exogenous administration of leukemia inhibitory factor(LIF).Mechanistically,miR-181 is able to directly target LIF and downregulate LIF expression,thereby inhibiting embryo implantation.We also show that miR-181 expression is regu-lated by the transcriptional factor Emx2,and the Emx2–miR-181 axis plays an importantrole in regulating embryo implantation.Taken together,these results reveal a novel function of miR-181 in embryo implantation through the regulation of LIF,and also indicate a potential link between miR-181 dysregulation and human embryo implantation defects.展开更多
A 500 kV high-voltage AC fault current limiter(FCL)based on a high coupled split reactor(HCSR)is pro-posed by the National key R&D project team.Low impedance under normal conditions and high impedance under short-...A 500 kV high-voltage AC fault current limiter(FCL)based on a high coupled split reactor(HCSR)is pro-posed by the National key R&D project team.Low impedance under normal conditions and high impedance under short-circuit conditions are accomplished by the cooperation of HCSR and high-speed switches.High-speed switches play an important role in current limiting processes,thus interruption characteristics of the high-speed switch in the 500 kV FCL are studied in this paper.The simulation model of the FCL and the external equivalent power grid are established.The short-circuit current and recovery voltage characteristics of the high-speed switch in FCL are simulated.The results show that maximum DC component of the short-circuit current of the high-speed switch reaches 91%,the maximum peak value is 118 kA,and the longest arcing time is 14.8 ms.There is a discontinuity in the curve of the short-circuit current peak and arcing time as a function of the short-circuit occurrence time;the peak recovery voltage of a single break of the high-speed switch has a maximum value of 87.5 kV under a three-phase ungrounded short-circuit condition,and the rate of rise of recovery voltage is o.22 kV/s.The recovery voltage peak shows a period change with the short-circuit occurrence time,and the period is 10 ms.The effects of the shunt capacitor value and short-circuit ground resistance on the recovery voltage of high-speed switching are also studied.The research can be used for reference by R&D personnel and testersof500kVFCLs.Index Terms-Fault current limiter(FCL),high coupled split reactor(HCSR),high-speed switch,interruption characteristics,short circuit current.展开更多
基金supported by the National Key Research and Development Project of Stem Cell and Transformation Research(2019YFA0112100)Taishan Scholars Programof Shandong Province-Young Taishan Scholars(tsqn201909197)+1 种基金Cutting Edge Development Fund of Advanced Medical Research Institute(Shandong University)National Natural Science Foundation of China(82220108005)。
文摘Traumatic spinal cord injury(SCI)is a debilitating condition characterized by the impairment of neural circuits,leading to the loss of motor and sensory functions and accompanied by severe complications.Substantial research has reported the therapeutic potential of Omega-3 fatty acids for the central nervous system,particularly after traumatic SCI.Omega-3 fatty acids may contribute to improving SCI recovery through their anti-inflammatory,anti-oxidative,neurotrophic,and membrane integrity-preserving properties.These functions of Omega-3 fatty acids are primarily mediated via the activation of G protein-coupled receptor 120(GPR120),commonly known as the fish oil-specific receptor.Advancements in understanding of the molecular mechanisms of GPR120’s recognition of Omega-3 fatty acids and its downstream signaling mechanisms has significantly promoted research on the pharmacological potential of Omega-3 fatty acids and the development of highly selective and high-affinity alternatives.This review aims to provide in-depth analysis of the comprehensive therapeutic potential of Omega-3 fatty acids for SCI and its accompanying complications,and the prospects for developing novel drugs based on the recognition of Omega-3 fatty acids by GPR120.
基金the financial support of the National Natural Science Foundation of China(No.52003254)the Shanxi Scholarship Council of China(No.2020–051)+3 种基金the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(No.2021SX-TD012)the Foundational Research Project of Shanxi Province(Nos.20210302123164,201901D211282,201901D211283)the Science Foundation of North University of China(No.XJJ201925)the MOE Key Laboratory of Macromolecular Synthesis and Functionalization,Zhejiang University(No.2021MSF01)。
文摘Developing non-conjugated luminescent polymers(NCLPs)with fluorescence and long-lived roomtemperature phosphorescence is of great significance for revealing the essence of NCLPs luminescence,which has gradually attracted the attention of researchers in recent years.Herein,polymethylol(PMO)and poly(3-butene-1,2-diol)(PBD)with polyhydroxy structures were prepared and their luminescence behaviors were investigated to reveal the clusteroluminescence(CL)mechanism.Compared with polyvinyl alcohol with non-luminescent behavior,PMO and PBD exhibit cyan-blue fluorescence with quantum yields of ca.12%and green room-temperature phosphorescence with lifetimes of ca.89 ms in the solid state.Both fluorescence and phosphorescence exhibit typical excitation-dependent CL behavior.Experimental and theoretical analyses show that the strong hydrogen-bonding interaction of PMO and PBD greatly promotes the formation of oxygen clusters and the through-space n-n interaction of oxygen atoms,enabling fluorescence and phosphorescence emission.Our results have enormous implications for understanding the CL mechanism of NCLPs and provide a new polymer design strategy for the rational design of novel NCLPs materials.
基金Supported by Nutrition and Development Center in Shanghai Children’s Medical Center
文摘AIM:To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori(H.pylori) treatment in children with H.pylori-associated functional dyspepsia.METHODS:Children with H.pylori-associated functional dyspepsia were enrolled in this study.H.pylori infection was confirmed by positive bacterial culture results.All of the children received triple H.pylori eradication therapy(a 2 wk course of omeprazole,amoxicillin,and clarithromycin).The children were divided into two groups based on the success of the H.pylori treatment:group 1(eradicated)-patients who had a negative 13C-urea breath test 2 mo after the end of therapy;and group 2(non-eradicated)-patients who had a positive 13C-urea breath test.Plasma ghrelin,gastric ghrelin mRNA,and the body mass index were evaluated in both groups before and after the H.pylori treatment.The plasma ghrelin levels were measured by a radioimmunoassay.The expression of gastric ghrelin mRNA was determined by real-time reverse transcription polymerase chain reaction.RESULTS:A total of 50 children with H.pylori-associated functional dyspepsia were treated with triple H.pylori eradication therapy.The mean age of the children was 5.52 ± 0.83 years,and there were 28 males and 22 females.Among the 50 H.pylori-positive children,30 successfully achieved eradication,and 20 did not.The mean plasma ghrelin levels of group 1 were 22.17 ± 1.73 ng/L and 26.59 ± 2.05 ng/L before and after the treatment,respectively,which was a significant increase(P = 0.001).However,the mean plasma ghrelin level of group 2 before and after the H.pylori treatment was 21.34 ± 2.40 ng/L and 22.24 ± 2.10 ng/L(P = 0.785).The plasma ghrelin levels increased substantially after treatment in group 1 but showed only minor changes in group 2.Similarly,the gastric ghrelin mRNA expression in group 1 before treatment was 2.84 ± 0.08.After treatment,the level was 3.11 ± 0.65,which was significantly different(P = 0.023).The gastric ghrelin mRNA expression in group 2 did not change significantly during the treatment(2.82 ± 0.44 vs 2.79 ± 0.31,P = 0.875).The plasma ghrelin and gastric ghrelin mRNA levels in group 1 increased substantially after the treatment but did not do so in group 2.In addition,the body mass index the two groups did not differ significantly 2 mo before and after the H.pylori treatment.CONCLUSION:H.pylori eradication increases the plasma and tissue ghrelin levels in children with H.pylori-associated functional dyspepsia.
基金the support of the National Natural Science Foundation of China(No.52003254)the support from the Fundamental Research Funds for the Central Universities(No.2021QNA4032)+5 种基金the Open Fund of Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates,and South China University of Technology(No.2019B030301003)the support of Shenzhen Key laboratory of Functional Aggregate Materials(No.ZDSYS20211021111400001)the Science and Technology Plan of Shenzhen(Nos.JCYJ2021324134613038 and GJHZ20210705141810031)the support of the National Natural Science Foundation of China(No.52073172)the financial support of the National Science Foundation of the People’s Republic of China(Nos.51973190 and 21774108)Zhejiang Provincial Department of Science and Technology(No.2020R52006)。
文摘Clusteroluminescence(CL)materials,as an emerging class of luminescent materials with unique photophysical properties,have received increasing attention owing to their great theoretical significance and potential for biological applications.Although much progress has been made in the design,synthesis and application of CL materials,there is still a big challenge in the emission mechanism.So far,throughspace interaction has been proposed as the preliminary mechanism of the corresponding clusterizationtriggered emission(CTE)effect,but a systematic theory is still needed.This review summarizes the current mechanistic understanding of CL materials including organic/inorganic small molecules,and polymers with/without isolated aromatic structures.In addition,some strategies to achieve high quantum yield,adjustable emission color,and persistent room temperature phosphorescence in CL materials are also summarized.At last,a perspective of the mechanism and application of CL materials are demonstrated,which inspire the researchers working on the development of new kinds of functional materials.
基金supported by the National Natural Science Foundation of China(No.40635026)
文摘The aircraft industry is crucial to the economy and security of a nation.In this paper,the spatial characteristics and patterns of the aircraft industry are analyzed on different spatial scales.It is found that there is a’Matthew effect’in the global aircraft industry and the spatial evolution of the industry is consistent with the industrialization process of the whole country.It is also revealed that the spatial evolution of the country is driven by both the centripetal forces including capital,talents,technology and agglomeration economies and the centrifugal forces including the comparative advantage,cost&risk sharing,emerging markets,development policy for less-developed regions and the military imperative.These forces have both market-stabilizing and market-disrupting effects on the spatial evolution of the aircraft industry.The study suggests that lessons drawn from the experiences in the United States and France are expected to be conducive to the rise of China’s aircraft industry in the future.
基金Fundamental Research Funds for the Central Universities,Grant/Award Number:2021QNA4032Molecular Aggregates and South China University of Technology,Grant/Award Number:2019B030301003+1 种基金National Science Foundation of the People’s Republic of China,Grant/Award Numbers:51973190,21774108Zhejiang Provincial Department of Science and Technology,Grant/Award Number:2020R52006。
文摘Clusteroluminogens(CLgens),nonconjugated structures with visible luminescence at the clustering state,have recently received remarkable attention due to their great theoretical significance and practical values.In carbonyl-based aliphatic polymers,(n,π*)transition of carbonyl groups and the through-space interactions have been demonstrated to play an important role in their clusteroluminescence(CL)properties,but it is still a big challenge to manipulate their CL at the molecular level.In this work,six nonconjugated carbonyl-based polymers with different heteroatoms and steric hindrances were synthesized,and their photophysical properties were systematically studied.These polymers all showed CL but with different emission efficiency and wavelength.Experimental and theoretical studies indicated that the CL properties could be manipulated by changing the electronic structures of carbonyl groups and the rigidity of polymer chains.This work not only gains further insights into the CL mechanism but also provides reliable strategies to design and manipulate non-conjugated luminescent materials.
基金This work was supported by grants from the Ministry of Science and Technology of China(2011CB966302,2013CB947900,2014CB910601,and 2013CB945502)the National Natural Science Foundation of China(81430065 and 31371388)+1 种基金the Fundamental Research Funds For Central Universities(WK2070000034)a Special Research Fund for the Doctoral Program of Higher Education from Ministry of Education of China(20123402130006).
文摘Embryo implantation is a crucial step in mammalian reproduction.However,little is known regarding the physiological roles of microRNAs in the regulation of embryo implantation.Here we show that a minimum uterine expression of miR-181 is essential for the onset of embryo implantation.Both transient and prolonged transgenic expression of miR-181 led to impaired implantation,which can be rescued by exogenous administration of leukemia inhibitory factor(LIF).Mechanistically,miR-181 is able to directly target LIF and downregulate LIF expression,thereby inhibiting embryo implantation.We also show that miR-181 expression is regu-lated by the transcriptional factor Emx2,and the Emx2–miR-181 axis plays an importantrole in regulating embryo implantation.Taken together,these results reveal a novel function of miR-181 in embryo implantation through the regulation of LIF,and also indicate a potential link between miR-181 dysregulation and human embryo implantation defects.
基金supported by the National Key R&D Program of China(2018YFB0904300)。
文摘A 500 kV high-voltage AC fault current limiter(FCL)based on a high coupled split reactor(HCSR)is pro-posed by the National key R&D project team.Low impedance under normal conditions and high impedance under short-circuit conditions are accomplished by the cooperation of HCSR and high-speed switches.High-speed switches play an important role in current limiting processes,thus interruption characteristics of the high-speed switch in the 500 kV FCL are studied in this paper.The simulation model of the FCL and the external equivalent power grid are established.The short-circuit current and recovery voltage characteristics of the high-speed switch in FCL are simulated.The results show that maximum DC component of the short-circuit current of the high-speed switch reaches 91%,the maximum peak value is 118 kA,and the longest arcing time is 14.8 ms.There is a discontinuity in the curve of the short-circuit current peak and arcing time as a function of the short-circuit occurrence time;the peak recovery voltage of a single break of the high-speed switch has a maximum value of 87.5 kV under a three-phase ungrounded short-circuit condition,and the rate of rise of recovery voltage is o.22 kV/s.The recovery voltage peak shows a period change with the short-circuit occurrence time,and the period is 10 ms.The effects of the shunt capacitor value and short-circuit ground resistance on the recovery voltage of high-speed switching are also studied.The research can be used for reference by R&D personnel and testersof500kVFCLs.Index Terms-Fault current limiter(FCL),high coupled split reactor(HCSR),high-speed switch,interruption characteristics,short circuit current.
