In recent years,it has been found that the flexibility of structure and diversity of the components endow quite an amount of the organic-inorganic hybrid perovskites with novel properties,i.e.,structural phase transit...In recent years,it has been found that the flexibility of structure and diversity of the components endow quite an amount of the organic-inorganic hybrid perovskites with novel properties,i.e.,structural phase transitions.Considering the natural advantage of the perovskite-type structure in generation of stimuliresponsive or smart materials,we synthesized an organic-inorganic hybrid rare-earth double perovskitetype compound,(DMP)_(2) LaRb(NO_(3))_(6)(DMP=N,N-dimethylpyrrolidinium cation,1).It shows reversible phase transition at 219/209 K(heating/cooling).Variable-temperature single-crystal structure analysis and dielectric constant measurements reveal that the thermal vibrations of the polar cation vips and the distortion of the anionic cage-like framework are the origin of the phase transition.Meanwhile,the movement of polar cation in crystal lattices arouses dielectric transition between the low-and highdielectric states,resulting in a switchable property of dielectric constant.The results reveal that the rare-earth double perovskite provides a promising platform for achieving switchable physical/chemical properties.展开更多
[ Objective] The aim of this paper was to investigate the genetic diversity of mitochondrial DNA D-loop sequences of Cheilinus undulatus populations. [Method] Twenty-five individuals of C. undu/atus were collected fro...[ Objective] The aim of this paper was to investigate the genetic diversity of mitochondrial DNA D-loop sequences of Cheilinus undulatus populations. [Method] Twenty-five individuals of C. undu/atus were collected from the offshore area of Hainan Province. PCR and cloning techniques were used to clone and purify the mtDNA D-loop sequences of C. undu/atus populations （n =25）, about 1 400 bp long PCR product was obtained. ClustalX software was adopted for sequence alignment, and results were imported into MEGAS. 0. [ Result] According to experimental results, 66 mutation sites were detected from 25 individuals, including 0 deletion, 4 inserts, 59 transition sites, 2 transversion sites and 1 transition-transversion site. Pairwise genetic distances of these 25 individuals were calcu- lated by using MEGA5.0 software. Based on that, NJ phylogenetic tree of these 25 individuals was constructed. Analysis of C. undulatus populations using DNASP software showed that the polymorphic site number （S） was 62, nucleotide diversity （Pi） was 0.006 06, and average number of nucleotide differences （K） was 6. 907. [ Conclusion] Overall, there was no significant variation among mtDNA D-loops of C. undulatus populations. Key words展开更多
Diabetes is a chronic metabolic disease with a high blood glucose level,leading to both seriously acute and chronic complications.The closed-loop system is an ideal system for diabetes management.However,the large siz...Diabetes is a chronic metabolic disease with a high blood glucose level,leading to both seriously acute and chronic complications.The closed-loop system is an ideal system for diabetes management.However,the large size and high cost of the commercial systems restrict their widespread uses.Here,we present for the first time a microtube-based wearable closed-loop minisystem for diabetes management.The closed-loop minisystem includes a biosensing device,an electroosmotic micropump,and a printed circuit board(PCB)with an algorithm.The microtube-based sensing device coated on the outer surface of the microtube is inserted into subcutaneous tissue for detecting interstitial glucose;the current signal for sensing glucose is processed by the PCB to power the electroosmotic micropump intelligently for the delivery of insulin into the subcutaneous tissue via the microtube channel.The closed-loop minisystem worn on a diabetic SD rat can successfully maintain its blood glucose level within a safe level.It is expected that this new closed-loop paradigm could open up new prospects for clinical diabetes management.展开更多
In the realm of molecular phase transition research,particularly for applications in sensors,data storage and switching technologies,the role of organic-inorganic hybrid perovskite materials has been increasingly reco...In the realm of molecular phase transition research,particularly for applications in sensors,data storage and switching technologies,the role of organic-inorganic hybrid perovskite materials has been increasingly recognized for their significant potential.Nevertheless,hybrid post-perovskites,as a critical subclass of perovskites,have not been thoroughly studied and mainly limit in the instances based on polyatomic bridging agents like dicyanamide(dca^(-))and non-cyclic organic cations.Herein,a polar cyclic quaternary ammonium cation,N,N-dimethylpyrrolidinium(DMP^(+)),was used to assemble a new hybrid post-perovskite,(DMP)[Mn(dca)_(3)](1),which undergoes a phase transition from orthorhombic Bmmb to monoclinic P2_(1)/n space group at 249 K.By employing multiple techniques such as differential scanning calorimetry,variable-temperature single-crystal X-ray analysis,dielectric measurements,and Hirshfeld surface analysis,we disclosed the role of polar cyclic quaternary ammonium DMP^(+)in elevating the phase-transition temperature by 48 K,generating significant dielectric switching effect and facilitating interlayer sliding of inorganic framework.展开更多
基金Project supported by the National Natural Science Foundation of China(21805119,21875093)Youth Science Foundation of Jiangxi Provincial Office of Science and Technology(20192ACBL21010)Natural Science Foundation of Jiangxi Province(20204BCJ22015,20202ACBL203001)。
文摘In recent years,it has been found that the flexibility of structure and diversity of the components endow quite an amount of the organic-inorganic hybrid perovskites with novel properties,i.e.,structural phase transitions.Considering the natural advantage of the perovskite-type structure in generation of stimuliresponsive or smart materials,we synthesized an organic-inorganic hybrid rare-earth double perovskitetype compound,(DMP)_(2) LaRb(NO_(3))_(6)(DMP=N,N-dimethylpyrrolidinium cation,1).It shows reversible phase transition at 219/209 K(heating/cooling).Variable-temperature single-crystal structure analysis and dielectric constant measurements reveal that the thermal vibrations of the polar cation vips and the distortion of the anionic cage-like framework are the origin of the phase transition.Meanwhile,the movement of polar cation in crystal lattices arouses dielectric transition between the low-and highdielectric states,resulting in a switchable property of dielectric constant.The results reveal that the rare-earth double perovskite provides a promising platform for achieving switchable physical/chemical properties.
基金Supported by National Natural Science Foundation of China(40966003)Natural Science Foundation of Hainan Province(809009)
文摘[ Objective] The aim of this paper was to investigate the genetic diversity of mitochondrial DNA D-loop sequences of Cheilinus undulatus populations. [Method] Twenty-five individuals of C. undu/atus were collected from the offshore area of Hainan Province. PCR and cloning techniques were used to clone and purify the mtDNA D-loop sequences of C. undu/atus populations （n =25）, about 1 400 bp long PCR product was obtained. ClustalX software was adopted for sequence alignment, and results were imported into MEGAS. 0. [ Result] According to experimental results, 66 mutation sites were detected from 25 individuals, including 0 deletion, 4 inserts, 59 transition sites, 2 transversion sites and 1 transition-transversion site. Pairwise genetic distances of these 25 individuals were calcu- lated by using MEGA5.0 software. Based on that, NJ phylogenetic tree of these 25 individuals was constructed. Analysis of C. undulatus populations using DNASP software showed that the polymorphic site number （S） was 62, nucleotide diversity （Pi） was 0.006 06, and average number of nucleotide differences （K） was 6. 907. [ Conclusion] Overall, there was no significant variation among mtDNA D-loops of C. undulatus populations. Key words
基金acknowledge the National High Level Hospital Clinical Research Funding(High Quality Clinical Research Project of Peking University First Hospital,No.2022CR83)National Natural Science Foundation of China(No.52072007 and No.82130021)+4 种基金National Key Research and Development Program of China(No.2018YFB1307301)CAMS Innovation Fund for Medical Sciences(2019-I2M-5-046 and 2020-JKCS-009)PKU-Baidu Fund(2020BD026 and 2020BD044)Capital's Funds for Health Improvement and Research(CFH2022-1-4071)Beijing Young Scientist Program(BJWZYJH01201910001006)for the financial support.
文摘Diabetes is a chronic metabolic disease with a high blood glucose level,leading to both seriously acute and chronic complications.The closed-loop system is an ideal system for diabetes management.However,the large size and high cost of the commercial systems restrict their widespread uses.Here,we present for the first time a microtube-based wearable closed-loop minisystem for diabetes management.The closed-loop minisystem includes a biosensing device,an electroosmotic micropump,and a printed circuit board(PCB)with an algorithm.The microtube-based sensing device coated on the outer surface of the microtube is inserted into subcutaneous tissue for detecting interstitial glucose;the current signal for sensing glucose is processed by the PCB to power the electroosmotic micropump intelligently for the delivery of insulin into the subcutaneous tissue via the microtube channel.The closed-loop minisystem worn on a diabetic SD rat can successfully maintain its blood glucose level within a safe level.It is expected that this new closed-loop paradigm could open up new prospects for clinical diabetes management.
基金supported by the National Natural Science Foundation of China(22071273 and 21821003)Fundamental Research Funds for the Central Universities,Sun Yat Sen University(23lgzy001).
文摘In the realm of molecular phase transition research,particularly for applications in sensors,data storage and switching technologies,the role of organic-inorganic hybrid perovskite materials has been increasingly recognized for their significant potential.Nevertheless,hybrid post-perovskites,as a critical subclass of perovskites,have not been thoroughly studied and mainly limit in the instances based on polyatomic bridging agents like dicyanamide(dca^(-))and non-cyclic organic cations.Herein,a polar cyclic quaternary ammonium cation,N,N-dimethylpyrrolidinium(DMP^(+)),was used to assemble a new hybrid post-perovskite,(DMP)[Mn(dca)_(3)](1),which undergoes a phase transition from orthorhombic Bmmb to monoclinic P2_(1)/n space group at 249 K.By employing multiple techniques such as differential scanning calorimetry,variable-temperature single-crystal X-ray analysis,dielectric measurements,and Hirshfeld surface analysis,we disclosed the role of polar cyclic quaternary ammonium DMP^(+)in elevating the phase-transition temperature by 48 K,generating significant dielectric switching effect and facilitating interlayer sliding of inorganic framework.
