Ligament cryopreservation enables a prolonged shelf life of allogeneic ligament grafts,which is fundamentally important to ligament reconstruction.However,conventional cryopreservation techniques fail to eliminate the...Ligament cryopreservation enables a prolonged shelf life of allogeneic ligament grafts,which is fundamentally important to ligament reconstruction.However,conventional cryopreservation techniques fail to eliminate the damage caused by ice crystal growth and the toxicity of cryopreservation agents(CPAs).Here,we report a novel CPA vitrification formulation primarily composed of betaine for ligament cryopreservation.Comprehensive optimization was conducted on the methods for vitrification and rewarming,as well as the loading and unloading conditions,based on the critical cooling rate(CCR),critical warming rate(CWR),and permeation properties of the CPA.Using biomechanical and histological level tests,we demonstrate the superior performance of our method in ligament cryopreservation.After 30 days of vitrification cryopreservation,parameters such as the Young's modulus,tensile stress,denaturation temperature,and glycosaminoglycans content of the ligament remained essentially unchanged.This work pioneers the application of ice-free cryopreservation for ligament and holds great potential for improving the long-term storage of ligament,providing valuable insights for future cryopreservation technique development.展开更多
Mulberry(Morus alba L.)seedlings were used to test hydrogen peroxide(H_(2)O_(2))as a potential systemic messenger in photosynthetic induction.The upper leaf of mulberry was dark-adapted for 45 min and then illuminated...Mulberry(Morus alba L.)seedlings were used to test hydrogen peroxide(H_(2)O_(2))as a potential systemic messenger in photosynthetic induction.The upper leaf of mulberry was dark-adapted for 45 min and then illuminated with photosynthetically active radiation(PAR)of1000μmol m^(-2)s^(-1).Photosynthetic induction and H_(2)O_(2) content in the lower leaf was measured.The results show that pre-illumination of the upper leaf promoted photosynthetic induction and increased endogenous H_(2)O_(2) in the lower leaf.Without pre-illuminating upper leaf,exogenous H_(2)O_(2) treatment on the lower leaf promoted photosynthetic induction.The application of diphenyleneiodonium and trichloroacetic acid on petioles of the upper leaf inhibited H_(2)O_(2) increase in the lower leaf,indicating that H_(2)O_(2) transport was from upper leaves to lower leaves through the phloem.The results show that H_(2)O_(2) might serve as a signal messenger to promote rapid induction of photosynthesis of leaves in lower parts of the canopy and enable plants to use light energy more efficiently.展开更多
Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing cycles.Herein,the mecha...Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing cycles.Herein,the mechanisms of surface-defect-induced icing are clarified.At the defects,water molecules exhibit stronger adsorption and the heat transfer rate increases,accelerating the condensation of water vapor as well as ice nucleation and propagation.Moreover,the ice–defect interlocking structure increases the ice adhesion strength.Thus,a self-healing(at−20℃)antifreeze-protein(AFP)-inspired anti-icing coating is developed.The coating is based on a design that mimics the ice-binding and non-ice-binding sites in AFPs.It enables the coating to markedly inhibit ice nucleation(nucleation temperature<−29.4℃),prevent ice propagation(propagation rate<0.00048 cm^(2)/s),and reduce ice adhesion on the surface(adhesion strength<38.9 kPa).More importantly,the coating can also autonomously self-heal at−20℃,as a result of multiple dynamic bonds in its structure,to inhibit defect-induced icing processes.The healed coating sustains high anti-icing and deicing performance even under various extreme conditions.This work reveals the in-depth mechanism of defect-induced ice formation as well as adhesion,and proposes a self-healing anti-icing coating for outdoor infrastructures.展开更多
Research about two-dimensional (2D) materials is growing exponentially across various scientific and engineering disciplines due to the wealth of unusual physical phenomena that occur when charge transport is confined...Research about two-dimensional (2D) materials is growing exponentially across various scientific and engineering disciplines due to the wealth of unusual physical phenomena that occur when charge transport is confined to a plane. The applications of 2D materials are highly affected by the electrical properties of these mat erials, including curren t dist ribution, surface pot ential, dielectric response, conductivity, perm计tivity, and piezoelectric response. Hence, it is very crucial to characterize these properties at the nanoscale. The Atomic Force Microscopy (AFM)-based techniques are powerful tools that can simultaneously characterize morphology and electrical properties of 2D materials with high spatial resolution, thus being more and more extensively used in this research field. Here, the principles of these AFM techniques are reviewed in detail. After that, their representative applications are further demonstrated in the local characterization of various 2D materials? elcctrical properties.展开更多
Few studies have described the key features and prognostic roles of lung microbiota in patients with severe community-acquired pneumonia(SCAP).We prospectively enrolled consecutive SCAP patients admitted to ICU.Bronch...Few studies have described the key features and prognostic roles of lung microbiota in patients with severe community-acquired pneumonia(SCAP).We prospectively enrolled consecutive SCAP patients admitted to ICU.Bronchoscopy was performed at bedside within 48 h of ICU admission,and 16S rRNA gene sequencing was applied to the collected bronchoalveolar lavage fluid.The primary outcome was clinical improvements defined as a decrease of 2 categories and above on a 7-category ordinal scale within 14 days following bronchoscopy.Sixty-seven patients were included.Multivariable permutational multivariate analysis of variance found that positive bacteria lab test results had the strongest independent association with lung microbiota(R2=0.033;P=0.018),followed by acute kidney injury(AKI;R2=0.032;P=0.011)and plasma MIP-1βlevel(R2=0.027;P=0.044).Random forest identified that the families Prevotellaceae,Moraxellaceae,and Staphylococcaceae were the biomarkers related to the positive bacteria lab test results.Multivariable Cox regression showed that the increase inα-diversity and the abundance of the families Prevotellaceae and Actinomycetaceae were associated with clinical improvements.The positive bacteria lab test results,AKI,and plasma MIP-1βlevel were associated with patients’lung microbiota composition on ICU admission.The families Prevotellaceae and Actinomycetaceae on admission predicted clinical improvements.展开更多
A range of soft robotic systems have recently been developed that use soft,flexible materials and respond to environmental stimulus.The greatest challenge in their design is the integration of the actuator,energy sour...A range of soft robotic systems have recently been developed that use soft,flexible materials and respond to environmental stimulus.The greatest challenge in their design is the integration of the actuator,energy sources,and body of robots while achieving fast locomotion and well-defined programmable trajectories.This work presents such a design that operates under constant conditions without the need for an externally modulated stimulus.By using a humidity-sensitive agarose film and overcoming the isotropic and random bending of the film,the robot,which we call the Hydrollbot,harnesses energy from evaporation for spontaneous and continuous fast self-rolling locomotion with a programmable trajectory in a constant-humidity environment.Moreover,the geometric parameters of the film were fine-tuned to maximize the rolling speed,and the optimised hydrollbot is capable of carrying a payload up to 100%of its own weight.The ability to self-propel fast under constant conditions with programmable trajectories will confer practical advantages to this robot in the applications for sensors,medical robots,actuation,etc.展开更多
Adiponectin has been demonstrated to be a mediator of insulin sensitivity;however,the underlined mechanisms remain unclear.SESN2 is a stress-inducible protein that phosphorylates AMPK in different tissues.In this stud...Adiponectin has been demonstrated to be a mediator of insulin sensitivity;however,the underlined mechanisms remain unclear.SESN2 is a stress-inducible protein that phosphorylates AMPK in different tissues.In this study,we aimed to validate the amelioration of insulin resistance by globular adiponectin(gAd)and to reveal the role of SESN2 in the improvement of glucose metabolism by gAd.We used a high-fat diet-induced wild-type and SESN2/C57BL/6J insulin resistance mice model to study the effects of six-week aerobic exercise or gAd administration on insulin resistance.In vitro study,C2C12 myotubes were used to determine the potential mechanism by overexpressing or inhibiting SESN2.Similar to exercise,six-week gAd administration decreased fasting glucose,triglyceride and insulin levels,reduced lipid deposition in skeletal muscle and reversed whole-body insulin resistance in mice fed on a high-fat diet.Moreover,gAd enhanced skeletal muscle glucose uptake by activating insulin signaling.However,these effects were diminished in SESN2/mice.We found that gAd administration increased the expression of SESN2 and Liver kinase B1(LKB1)and increased AMPK-T172 phosphorylation in skeletal muscle of wild-type mice,while in SESN2/mice,LKB1 expression was also increased but the pAMPKT172 was unchanged.At the cellular level,gAd increased cellular SESN2 and pAMPK-T172 expression.Immunoprecipitation experiment suggested that SESN2 promoted the formation of complexes of AMPK and LKB1 and hence phosphorylated AMPK.In conclusion,our results revealed that SESN2 played a critical role in gAd-induced AMPK phosphorylation,activation of insulin signaling and skeletal muscle insulin sensitization in mice with insulin resistance.展开更多
基金supported by the National Natural Science Foundation of China(22078238,U23B20121)。
文摘Ligament cryopreservation enables a prolonged shelf life of allogeneic ligament grafts,which is fundamentally important to ligament reconstruction.However,conventional cryopreservation techniques fail to eliminate the damage caused by ice crystal growth and the toxicity of cryopreservation agents(CPAs).Here,we report a novel CPA vitrification formulation primarily composed of betaine for ligament cryopreservation.Comprehensive optimization was conducted on the methods for vitrification and rewarming,as well as the loading and unloading conditions,based on the critical cooling rate(CCR),critical warming rate(CWR),and permeation properties of the CPA.Using biomechanical and histological level tests,we demonstrate the superior performance of our method in ligament cryopreservation.After 30 days of vitrification cryopreservation,parameters such as the Young's modulus,tensile stress,denaturation temperature,and glycosaminoglycans content of the ligament remained essentially unchanged.This work pioneers the application of ice-free cryopreservation for ligament and holds great potential for improving the long-term storage of ligament,providing valuable insights for future cryopreservation technique development.
基金supported by State Key Laboratory of Tree Genetics and Breeding(Northeast Forestry University)Youth Foundation of Northeast Agricultural University(No.17QC36)。
文摘Mulberry(Morus alba L.)seedlings were used to test hydrogen peroxide(H_(2)O_(2))as a potential systemic messenger in photosynthetic induction.The upper leaf of mulberry was dark-adapted for 45 min and then illuminated with photosynthetically active radiation(PAR)of1000μmol m^(-2)s^(-1).Photosynthetic induction and H_(2)O_(2) content in the lower leaf was measured.The results show that pre-illumination of the upper leaf promoted photosynthetic induction and increased endogenous H_(2)O_(2) in the lower leaf.Without pre-illuminating upper leaf,exogenous H_(2)O_(2) treatment on the lower leaf promoted photosynthetic induction.The application of diphenyleneiodonium and trichloroacetic acid on petioles of the upper leaf inhibited H_(2)O_(2) increase in the lower leaf,indicating that H_(2)O_(2) transport was from upper leaves to lower leaves through the phloem.The results show that H_(2)O_(2) might serve as a signal messenger to promote rapid induction of photosynthesis of leaves in lower parts of the canopy and enable plants to use light energy more efficiently.
基金the National Key Research and Development Program of China(2022YFC2104800 and 2021YFC2100800)the National Natural Science Foundation of China(22078238,21908160,and 21961132005).
文摘Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing cycles.Herein,the mechanisms of surface-defect-induced icing are clarified.At the defects,water molecules exhibit stronger adsorption and the heat transfer rate increases,accelerating the condensation of water vapor as well as ice nucleation and propagation.Moreover,the ice–defect interlocking structure increases the ice adhesion strength.Thus,a self-healing(at−20℃)antifreeze-protein(AFP)-inspired anti-icing coating is developed.The coating is based on a design that mimics the ice-binding and non-ice-binding sites in AFPs.It enables the coating to markedly inhibit ice nucleation(nucleation temperature<−29.4℃),prevent ice propagation(propagation rate<0.00048 cm^(2)/s),and reduce ice adhesion on the surface(adhesion strength<38.9 kPa).More importantly,the coating can also autonomously self-heal at−20℃,as a result of multiple dynamic bonds in its structure,to inhibit defect-induced icing processes.The healed coating sustains high anti-icing and deicing performance even under various extreme conditions.This work reveals the in-depth mechanism of defect-induced ice formation as well as adhesion,and proposes a self-healing anti-icing coating for outdoor infrastructures.
基金the National Natural Science Foundation of China (NSFC)(Nos. 21622304, 61674045, and 11604063)the Ministry of Science and Technology (MOST) of China (No. 2016YFA0200700)+2 种基金the Strategic Priority Research Program, the Key Research Program of Frontier Sciences and Instrument Developing Project of Chinese Academy of Sciences (CAS)(Nos. XDB30000000, QYZDB-SSW-SYS031, and YZ201418)Osaka University's International Joint Research Promotion Program (Nos. J171013014 and J171013007)Z.H. Cheng was supported by Distinguished Technical Talents Project and Youth Innovation Promotion Association CAS, the Fundamental Research Funds for the Central Universities and the Research Funds of Renmin University of China (No. 18XNLG01).
文摘Research about two-dimensional (2D) materials is growing exponentially across various scientific and engineering disciplines due to the wealth of unusual physical phenomena that occur when charge transport is confined to a plane. The applications of 2D materials are highly affected by the electrical properties of these mat erials, including curren t dist ribution, surface pot ential, dielectric response, conductivity, perm计tivity, and piezoelectric response. Hence, it is very crucial to characterize these properties at the nanoscale. The Atomic Force Microscopy (AFM)-based techniques are powerful tools that can simultaneously characterize morphology and electrical properties of 2D materials with high spatial resolution, thus being more and more extensively used in this research field. Here, the principles of these AFM techniques are reviewed in detail. After that, their representative applications are further demonstrated in the local characterization of various 2D materials? elcctrical properties.
基金funded by the National Key Research and Devclopment Program of China(No,2017YFC1309301)the CAMS Innovation Fund for Medical Sciences(CIFMS:No.2018-12M-1-003)+1 种基金the National Science Grant for Distinguished Young Scholars(No.81425001/H0104)the Ministry of Science and Technology of China No.2017ZX10103004).
文摘Few studies have described the key features and prognostic roles of lung microbiota in patients with severe community-acquired pneumonia(SCAP).We prospectively enrolled consecutive SCAP patients admitted to ICU.Bronchoscopy was performed at bedside within 48 h of ICU admission,and 16S rRNA gene sequencing was applied to the collected bronchoalveolar lavage fluid.The primary outcome was clinical improvements defined as a decrease of 2 categories and above on a 7-category ordinal scale within 14 days following bronchoscopy.Sixty-seven patients were included.Multivariable permutational multivariate analysis of variance found that positive bacteria lab test results had the strongest independent association with lung microbiota(R2=0.033;P=0.018),followed by acute kidney injury(AKI;R2=0.032;P=0.011)and plasma MIP-1βlevel(R2=0.027;P=0.044).Random forest identified that the families Prevotellaceae,Moraxellaceae,and Staphylococcaceae were the biomarkers related to the positive bacteria lab test results.Multivariable Cox regression showed that the increase inα-diversity and the abundance of the families Prevotellaceae and Actinomycetaceae were associated with clinical improvements.The positive bacteria lab test results,AKI,and plasma MIP-1βlevel were associated with patients’lung microbiota composition on ICU admission.The families Prevotellaceae and Actinomycetaceae on admission predicted clinical improvements.
基金The authors greatly acknowledge the support of the National Natural Science Foundation of China(Y.C.:Projects 51825503,52035008,and51721003,L.Z.:Projects 21961132005 and 21621004)and the Tencent Foundation(XPLORER-2020-1035).
文摘A range of soft robotic systems have recently been developed that use soft,flexible materials and respond to environmental stimulus.The greatest challenge in their design is the integration of the actuator,energy sources,and body of robots while achieving fast locomotion and well-defined programmable trajectories.This work presents such a design that operates under constant conditions without the need for an externally modulated stimulus.By using a humidity-sensitive agarose film and overcoming the isotropic and random bending of the film,the robot,which we call the Hydrollbot,harnesses energy from evaporation for spontaneous and continuous fast self-rolling locomotion with a programmable trajectory in a constant-humidity environment.Moreover,the geometric parameters of the film were fine-tuned to maximize the rolling speed,and the optimised hydrollbot is capable of carrying a payload up to 100%of its own weight.The ability to self-propel fast under constant conditions with programmable trajectories will confer practical advantages to this robot in the applications for sensors,medical robots,actuation,etc.
基金supported by grants from the Natural Science Foundation of China(NSFC)31871206,32171135(to LF),and 31671237(to YMN).
文摘Adiponectin has been demonstrated to be a mediator of insulin sensitivity;however,the underlined mechanisms remain unclear.SESN2 is a stress-inducible protein that phosphorylates AMPK in different tissues.In this study,we aimed to validate the amelioration of insulin resistance by globular adiponectin(gAd)and to reveal the role of SESN2 in the improvement of glucose metabolism by gAd.We used a high-fat diet-induced wild-type and SESN2/C57BL/6J insulin resistance mice model to study the effects of six-week aerobic exercise or gAd administration on insulin resistance.In vitro study,C2C12 myotubes were used to determine the potential mechanism by overexpressing or inhibiting SESN2.Similar to exercise,six-week gAd administration decreased fasting glucose,triglyceride and insulin levels,reduced lipid deposition in skeletal muscle and reversed whole-body insulin resistance in mice fed on a high-fat diet.Moreover,gAd enhanced skeletal muscle glucose uptake by activating insulin signaling.However,these effects were diminished in SESN2/mice.We found that gAd administration increased the expression of SESN2 and Liver kinase B1(LKB1)and increased AMPK-T172 phosphorylation in skeletal muscle of wild-type mice,while in SESN2/mice,LKB1 expression was also increased but the pAMPKT172 was unchanged.At the cellular level,gAd increased cellular SESN2 and pAMPK-T172 expression.Immunoprecipitation experiment suggested that SESN2 promoted the formation of complexes of AMPK and LKB1 and hence phosphorylated AMPK.In conclusion,our results revealed that SESN2 played a critical role in gAd-induced AMPK phosphorylation,activation of insulin signaling and skeletal muscle insulin sensitization in mice with insulin resistance.
