Recent evidence highlights multifaceted biological needs to recapitulate the bone microenvironment for bone regeneration.Neurotization has great potential for realizing multi-system modulations in bone tissue engineer...Recent evidence highlights multifaceted biological needs to recapitulate the bone microenvironment for bone regeneration.Neurotization has great potential for realizing multi-system modulations in bone tissue engineering(BTE).However,a neural strategy involving all the key bone repair steps temporally has not yet been reported.In this study,we reported the neural tissue engineering hydrogel-encapsulated Schwann cell-derived exosomes(SC Exo).This sustained-release SC Exo system prominently enhanced bone regeneration by promoting innervation,immunoregulation,vascularization,and osteogenesis in vivo.Moreover,the in vitro results further confirmed that this system significantly induced M2 polarization of macrophages,tube formation of HUVECs,and BMSCs osteogenic differentiation.Furthermore,BMSCs osteogenesis was promoted by upregulating the TGF-β1/SMAD2/3 signaling pathway.In summary,a novel cell-free and easily prepared SC Exo neural engineering was successfully developed to promote bone regeneration by orchestrating the entire bone healing microenvironment,which may provide a new strategy for tissue engineering and clinical treatment of bone defects.展开更多
The vigorous expansion of renewable energy as a substitute for fossil energy is the predominant route of action to achieve worldwide carbon neutrality. However, clean energy supplies in multi-energy building districts...The vigorous expansion of renewable energy as a substitute for fossil energy is the predominant route of action to achieve worldwide carbon neutrality. However, clean energy supplies in multi-energy building districts are still at the preliminary stages for energy paradigm transitions. In particular, technologies and methodologies for large-scale renewable energy integrations are still not sufficiently sophisticated, in terms of intelligent control management. Artificial intelligent (AI) techniques powered renewable energy systems can learn from bioinspired lessons and provide power systems with intelligence. However, there are few in-depth dissections and deliberations on the roles of AI techniques for large-scale integrations of renewable energy and decarbonisation in multi-energy systems. This study summarizes the commonly used AI-related approaches and discusses their functional advantages when being applied in various renewable energy sectors, as well as their functional contribution to optimizing the operational control modalities of renewable energy and improving the overall operational effectiveness. This study also presents practical applications of various AI techniques in large-scale renewable energy integration systems, and analyzes their effectiveness through theoretical explanations and diverse case studies. In addition, this study introduces limitations and challenges associated with the large-scale renewable energy integrations for carbon neutrality transition using relevant AI techniques, and proposes further promising research perspectives and recommendations. This comprehensive review ignites advanced AI techniques for large-scale renewable integrations and provides valuable informational instructions and guidelines to different stakeholders (e.g., engineers, designers and scientists) for carbon neutrality transition.展开更多
Traditional therapies such as surgery and endocrine therapy no longer meet the clinical needs in prostate cancer treatment,and more effective treatments are urgently required.Recent studies have reported that targeted...Traditional therapies such as surgery and endocrine therapy no longer meet the clinical needs in prostate cancer treatment,and more effective treatments are urgently required.Recent studies have reported that targeted inhibition of the transcription factor cyclin dependent kinase 7(CDK7)could effectively suppress prostate cancer progression.However,the toxicity of CDK7 inhibitors such as THZ1 is the main limitation of the clinical application.In this work,we synthesized Cys8E(C8E)nanoparticles(NPs)loaded with THZ1(C8E@THZ1),a novel GSH-targeting and stimuli-responsive nano-delivery platform,and investigated its anti-tumor potential and biosafety properties.In vitro,C8E@THZ1 potently inhibited the proliferation and promoted the apoptosis of prostate cancer cells.On tumor-bearing mice,C8E@THZ1 inhibited tumors by up to 85%,while the damage of THZ1 to liver function was effectively avoided.These results confirmed that inhibition of CDK7 can effectively block the progression of prostate cancer,and that Cys8E NPs is a highly prospective delivery platform to promote the clinical application of CDK7 inhibitors.展开更多
Lithium(Li)dendrite growth significantly deteriorates the performance and shortens the operation life of lithium metal batteries.Capturing the intricate dynamics of surface localized and rapid mass transport at the el...Lithium(Li)dendrite growth significantly deteriorates the performance and shortens the operation life of lithium metal batteries.Capturing the intricate dynamics of surface localized and rapid mass transport at the electrolyte–electrode interface of lithium metal is essential for the understanding of the dendrite growth process,and the evaluation of the solutions mitigating the dendrite growth issue.Here we demonstrate an approach based on an ultrasensitive tilted fiber Bragg grating(TFBG)sensor which is inserted close to the electrode surface in a working lithium metal battery,without disturbing its operation.Thanks to the superfine optical resonances of the TFBG,in situ and rapid monitoring of mass transport kinetics and lithium dendrite growth at the nanoscale interface of lithium anodes have been achieved.Reliable correlations between the performance of different natural/artificial solid electrolyte interphases(SEIs)and the time-resolved optical responses have been observed and quantified,enabling us to link the nanoscale ion and SEI behavior with the macroscopic battery performance.This new operando tool will provide additional capabilities for parametrization of the batteries’electrochemistry and help identify the optimal interphases of lithium metal batteries to enhance battery performance and its safety.展开更多
Visible light-based human–machine interactive media is capable of transmitting electrical readouts to machines and providing intuitive feedback to users simultaneously.Currently,many inorganic mechanoluminescent(ML)m...Visible light-based human–machine interactive media is capable of transmitting electrical readouts to machines and providing intuitive feedback to users simultaneously.Currently,many inorganic mechanoluminescent(ML)materials-based interactive media,typically ZnS-loaded phosphors(ZLPs),have been successfully demonstrated.However,organic ML materials-based solutions were rarely exploited despite their huge merits of strong structural modification,abundant luminescence property,low cost,easy preparation,and so on.Here,we propose a novel interactive tactile display(ITD)based on organic ML materials(Cz-A6-dye)and triboelectric nanogenerator,with ultra-brightness(130%enhancement)and ultra-low threshold pressure(57%reduction)as compared to ZLPs.The proposed ITD achieves the conversion of weak mechanical stimuli into visible light and electrical signals simultaneously,without extra power supplies.Furthermore,the relationship between the luminous performance of organic ML materials and mechanical force is quantified,benefiting from the uniform ML layer prepared.Enabled by convolutional neural networks,the high-accuracy recognition(97.1%)for handwriting and identity of users is realized at the same time.Thus,the ITD has great potential for intelligent wearable electronics and classified military applications.展开更多
Macrophages,as a subset of innate immune cells,play a pivotal role in the initiation,maintenance,and resolution of inflammatory responses during tissue damage repair,defense against infections,and tumor progression.Ho...Macrophages,as a subset of innate immune cells,play a pivotal role in the initiation,maintenance,and resolution of inflammatory responses during tissue damage repair,defense against infections,and tumor progression.However,the mechanisms by which macrophages regulate inflammation in acute myeloid leukemia(AML)and their involvement in the chemotherapeutic effect remain elusive.In this study,we have identified that AML cells stimulate macrophage expansion by activating the colony-stimulating factor 1 receptor(CSF1R)pathway.The expanded macrophages activate nuclear factor kappa-B(NFκB)to induce the expression of inflammatory factors,thereby maintaining leukemic cell quiescence and promoting cell survival following chemotherapy.Furthermore,we have successfully utilized a poly(ferulic acid)nanocarrier to selectively target macrophages for inhibiting the NFκB-mediated inflammation,ultimately enhancing chemotherapy efficacy against AML.Taken together,our findings highlight the crucial role of macrophage-induced inflammation in conferring chemoresistance to AML,and demonstrate the potential of a targeted nanocarrier specifically designed for inflammatory macrophages to improve the AML chemotherapeutic outcomes.展开更多
Enhancing the active tumor targeting ability and decreasing the clearance of reticuloendothelial system(RES)are important issues for drug delivery systems(DDSs)in cancer therapy.In recent years,cell membrane camouflag...Enhancing the active tumor targeting ability and decreasing the clearance of reticuloendothelial system(RES)are important issues for drug delivery systems(DDSs)in cancer therapy.In recent years,cell membrane camouflage,as one of the biomimetic modification strategies,has shown huge potential.Many natural properties of source cells can be inherited,allowing the DDSs to successfully avoid phagocytosis by macrophages,prolong circulation time,and achieve homologous targeting to lesion tissue.In this study,a cancer cell membrane camouflaged nanoplatform based on gelatin with a typical core-shell structure was developed for cancer chemotherapy.Doxorubicin(DOX)loaded gelatin nanogel(NG@DOX)acted as the inner core,and 4T1(mouse breast carcinoma cell)membrane was set as the outer shell(M-NG@DOX).The M-NG platform enhanced the ability of homologous targeting due to the surface protein of cell membrane being completely retained,which could promote the cell uptake of homotypic cells,avoid phagocytosis by RAW264.7 macrophages,and therefore increase accumulation in tumor tissue.Meanwhile,due to the better controlled drug release capability of M-NG@DOX,premature release of DOX in circulation could be reduced,minimizing side effects in common chemotherapy.As a result,the biomimetic nanoplatform in this study,obtained by a cancer cell membrane camouflaged drug delivery system,efficiently reached desirable tumor elimination,providing a significant strategy for effective targeted therapy and specific carcinoma therapy.展开更多
Colorectal cancer is a common cancer worldwide.Traditional chemotherapeutic drugs often face limitations such as poor aqueous solubility and high systemic toxicity,which can lead to adverse side effects and limited th...Colorectal cancer is a common cancer worldwide.Traditional chemotherapeutic drugs often face limitations such as poor aqueous solubility and high systemic toxicity,which can lead to adverse side effects and limited therapeutic efficacy.In this study,a library of one kind of biodegradable and biocompatible polymer,leucine based-poly(ester amide)s(Leu-PEAs)was developed and utilized as drug carrier.The structure of Leu-PEAs can be tuned to alter their physicochemical properties,enhancing drug loading capacity and delivery efficiency.Leu-PEAs can self-assemble into nanoparticles by nanoprecipitation and load paclitaxel(PTX)with the diameter of~108 nm and PTX loading capacity of~8.5%.PTX-loaded Leu-PEAs nanoparticles(PTX@Leu-PEAs)demonstrated significant inhibition of CT26 cell growth in vitro.In vivo,these nanoparticles exhibited prolonged tumor accumulation and antitumor effects,with no observed toxicity to normal organs.Furthermore,blank Leu-PEAs nanoparticles also showed antitumor effects in vitro and in vivo,which may be attributed to the activation of the mammalian target of rapamycin(m TOR)pathway by leucine.Consequently,this biocompatible Leu-PEAs nano-drug delivery system shows potential as a promising strategy for colorectal cancer treatment,warranting further investigation.展开更多
Oxidative stress and inflammation are key drivers of osteoarthritis(OA)pathogenesis and disease progression.Herein we report the synthesis of poly(p-coumaric)nanoparticles(PCA NPs)from p-courmaic acid(p-CA),a naturall...Oxidative stress and inflammation are key drivers of osteoarthritis(OA)pathogenesis and disease progression.Herein we report the synthesis of poly(p-coumaric)nanoparticles(PCA NPs)from p-courmaic acid(p-CA),a naturally occurring phytophenolic acid,to be a multifunctional and drug-free therapeutic for temporomandibular joint osteoarthritis(TMJOA).Compared to hyaluronic acid(HA)that is clinically given as viscosupplementation,PCA NPs exhibited long-term efficacy,superior anti-oxidant and anti-inflammatory properties in alleviating TMJOA and repairing the TMJ cartilage and subchondral bone in a rat model of TMJOA.Notably,TMJ repair mediated by PCA NPs could be attributed to their anti-oxidant and anti-inflammatory properties in enhancing cell proliferation and matrix synthesis,while reducing inflammation,oxidative stress,matrix degradation,and chondrocyte ferroptosis.Overall,our study demonstrates a multifunctional nanoparticle,synthesized from natural p-coumaric acid,that is stable and possess potent antioxidant,anti-inflammatory properties and ferroptosis inhibition,beneficial for treatment of TMJOA.展开更多
In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture network.It has been proven to cause inaccurate pro...In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture network.It has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture communication.In addition,most of the existing models are solved analytically based on Laplace transform and numerical inversion.Hence,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix depletion.To simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the microfractures.Then,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by integration.Finally,a relationship between oil rate and production time in real-time space is obtained.The new model is verified against classical analytical models.When the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,respectively.Certainly,the new model also has an excellent agreement with the numerical model.The model is then applied to two actual tight oil wells completed in western Canada sedimentary basin.After identifying the flow regime,the solution suitably matches the field production data,and the model parameters are determined.Through these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.展开更多
In recent years,the incidence of myopia has increased at an alarming rate among children and adolescents in China.The exploration of an effective prevention and control method for myopia is in urgent need.With the dev...In recent years,the incidence of myopia has increased at an alarming rate among children and adolescents in China.The exploration of an effective prevention and control method for myopia is in urgent need.With the development of information technology in the past decade,artificial intelligence with the Internet of Things technology(AIoT)is characterized by strong computing power,advanced algorithm,continuous monitoring,and accurate prediction of long-term progression.Therefore,big data and artificial intelligence technology have the potential to be applied to data mining of myopia etiology and prediction of myopia occurrence and development.More recently,there has been a growing recognition that myopia study involving AIoT needs to undergo a rigorous evaluation to demonstrate robust results.展开更多
High oxidative stress injury and bacterial infection are the main challenges that impair wound healing in diabetic patients.Therefore,a hydrogel with enhanced antimicrobial and antioxidant properties was developed for...High oxidative stress injury and bacterial infection are the main challenges that impair wound healing in diabetic patients.Therefore,a hydrogel with enhanced antimicrobial and antioxidant properties was developed for rapid healing of diabetic wounds.In this study,chitosan methacrylate-gallic acid(CSMA-GA)polymer with antioxidant activity,antimicrobial activity,and ultraviolet(UV)-triggered gelling properties was developed as a hydrogel precursor.Meanwhile,amphiphilic Pluronic F127 molecules were used to load hydrophobic chlorhexidine drug molecules to obtain F127/chlorhexidine nanoparticle(NP)with strong antibacterial activity.Subsequently,F127/chlorhexidine NPs were encapsulated in CSMA-GA hydrogel to further enhance its antibacterial activity.The hybrid hydrogel platform(CSMA-GA/F127/chlorhexidine(CMGFC))exhibited high antibacterial efficiency(>99.9%)and strong reactive oxygen species(ROS)scavenging ability(>80.0%),which effectively protected cells from external oxidative stress(upregulated superoxide dismutase(SOD)and glutathione/oxidized glutathione disulfide(GSH/GSSG)levels and downregulated malondialdehyde(MDA)levels).Moreover,in vivo results proved that the CMGFC hydrogel significantly reduced inflammatory responses(downregulated interleukin-6(IL-6)and upregulated interleukin-10(IL-10)levels),promoted angiogenesis(upregulated vascular endothelial growth factor(VEGF)and platelet endothelial cell adhesion molecule-1(CD 31)levels),and wound healing(enhanced collagen deposition and tissue remodelling).Overall,the CMGFC hydrogel with enhanced antimicrobial and antioxidant properties demonstrated significant potential to enhance diabetic wound healing.展开更多
Reliable technologies for CO_(2) capture and conversion(C3) are of vital importance for the establishment of a sustainable society.Metal-organic framework(MOF) composites have shown their compelling potentials for C3 ...Reliable technologies for CO_(2) capture and conversion(C3) are of vital importance for the establishment of a sustainable society.Metal-organic framework(MOF) composites have shown their compelling potentials for C3 due to the plentiful reticular chemistry of MOF structures and the synergistic catalysis between MOFs and the functional guests.This review focuses on the syntheses and catalytic applications towards C3 of MOF composites,which is divided into three sections.The first section gives a brief introduction about synthetic strategies of MOF composites.The second section discusses the recent progress of MOF composites in C3,including CO_(2) chemical fixation,hydrogenation,photoreduction,electro reduction and photoelectro reduction.The third section summarizes the challenges and future prospects of MOF composites for C3.We hope that this review cannot only provide an inspiration for the rational design of MOF composites for C3,but also stimulate more and more research works in this emerging area.展开更多
The long-term trends in the occurrence frequency of pre-summer daytime and nocturnal extreme hourly rainfall(EXHR) during 1988-2018 in Hong Kong and their spatial distributions are examined and analyzed. Despite a sig...The long-term trends in the occurrence frequency of pre-summer daytime and nocturnal extreme hourly rainfall(EXHR) during 1988-2018 in Hong Kong and their spatial distributions are examined and analyzed. Despite a significant increasing trend observed in the occurrence frequency of pre-summer EXHRs during the investigated period,the increase in daytime and nocturnal EXHRs show distinct spatial patterns. Nocturnal EXHRs show uniform increasing trends over the entire Hong Kong. However, the increase in daytime EXHRs is concentrated over the northern or eastern areas of Hong Kong, indicating a downstream shift of pre-summer EXHRs in Hong Kong with regard to the prevailing southwesterly monsoonal flows in south China. The clustering of weather types associated with daytime and nocturnal EXHRs further reveals that the increase in EXHRs over Hong Kong are mainly contributed by the increase of the events associated with southwesterly monsoonal flows with relatively high speeds. During the past few decades, the southwesterly monsoonal flows at coastal south China have undergone a substantial weakening due to the increased surface roughness induced by the urbanization over the Guangdong-Hong Kong-Macao Greater Bay Area since 1990s,leading to enhanced low-level convergence and thus significant increase in EXHRs at coastal south China. Meanwhile,daytime sea-wind circulation at coastal south China is markedly enhanced during the investigated period, which is the main reason for the northward shift of daytime EXHRs in Hong Kong. In addition, the blocked southwesterly monsoonal flows at coastal south China are detoured eastward, leading to stronger convergence and increase in EXHRs at eastern coast of Hong Kong, especially during daytime, when the easterly sea winds prevail at the region.展开更多
Supported nickel catalysts are promising candidates for dry reforming of methane, but agglomeration of Ni^(0) and coke deposition hinder the industrial applications. Herein, we report a novel interface-directed synthe...Supported nickel catalysts are promising candidates for dry reforming of methane, but agglomeration of Ni^(0) and coke deposition hinder the industrial applications. Herein, we report a novel interface-directed synthetic approach to construct distinct metal ensembles by carefully tuning the compositions of the carriers. A Zr-Mn-Zn ternary oxide-supported Ni catalyst, together with the respective binary oxide-supported analogues, was synthesized by adopting a sequential co-precipitation and wetness impregnation method. Combined characterization techniques identify distinct catalyst models, including (i) conventional NiO nanoparticles with different sizes on Zr-Mn and Zr-Zn, and (ii) epitaxially growing NiO ensembles of a few nanometers thickness at the periphery of ZnO_(x) particles. These catalysts exhibit divergent responses in the catalytic testing, with the ternary oxide system significantly outperforming the binary analogues. The strong electronic interactions between Mn-Ni increase Ni dispersion and the activity while the stability is strengthened upon Zn addition. Both high activity, high selectivity, and remarkable stability are attained upon co-adding Mn and Zn. The interfaces between Ni and Zr-Mn-Zn rather than the physical contacts of individual oxide-supported analogues through mechanical mixing are keys for the outstanding performance.展开更多
As a representative of chronic wounds,the long-term high levels of oxidative stress and blood sugar in chronic diabetic wounds lead to serious complications,making them the biggest challenge in the research on wound h...As a representative of chronic wounds,the long-term high levels of oxidative stress and blood sugar in chronic diabetic wounds lead to serious complications,making them the biggest challenge in the research on wound healing.Many edible natural biomaterials rich in terpenes,phenols,and flavonoids can act as efficient antioxidants.In this study,okra extract was selected as the main component of a wound dressing.The okra extracts obtained via different methods comprehensively maintained the bioactivity of multiple molecules.The robust antioxidant properties of okra significantly reduced intracellular reactive oxygen species production,thereby accelerating the wound healing process.The results showed that okra extracts and their hydrogel dressings increased cell migration,angiogenesis,and re-epithelization of the chronic wound area,considerably promoting wound remodeling in diabetic rats.Therefore,okra-based hydrogels are promising candidates for skin regeneration and wider tissue engineering applications.展开更多
Triboelectric nanogenerators(TENGs)represent a promising next‐generation renewable energy technology.TENGs have become increasingly popular for harvesting vibration energy in the environment due to their advantages o...Triboelectric nanogenerators(TENGs)represent a promising next‐generation renewable energy technology.TENGs have become increasingly popular for harvesting vibration energy in the environment due to their advantages of lightweight,broad range of material choices,low cost,and no pollution.However,issues such as input force irregularity,working bandwidth,efficiency calculation,and dynamic modeling hinder the use of TENGs in industrial or practical applications.In this paper,the modeling process of the dynamical system of a TENG is reviewed from the perspective of energy flow.In addition,this paper reviews the main contributions made in recent years to achieve optimized output based on springs,magnetic forces,and pendulums,and introduces different ways to increase the bandwidth of TENGs.Finally,the main problems of TENGs in the process of harvesting vibration energy are discussed.This review may serve as a practical reference for methods to convert irregular mechanical input sources into optimized output performance toward the commercialization of TENGs.展开更多
A narrow resonance bandwidth of an energy harvesters limits its response to the wide frequency spectrum in ambient environ-ments.This work proposes an addition of a nonlinear restoring force applied to a triboelectric...A narrow resonance bandwidth of an energy harvesters limits its response to the wide frequency spectrum in ambient environ-ments.This work proposes an addition of a nonlinear restoring force applied to a triboelectric nanogenerator(TENG)to tune and broaden the resonance bandwidth.This restoring force is applied by permanent magnets at both sides of the slider and two external magnets.The noncontact strategy is adopted between the slider and the grating electrodes to avoid the wear of electrodes and energy loss caused by friction.The results show that compared with the linear system,the nonlinear noncontact TENG(NN-TENG)can increase the peak current from 6.3μA to 7.89μA,with an increment of about 25%,increase the peak power from 650μW to 977μW,increasing by about 50%,and increase the bandwidth from 0.5 Hz to 7.75 Hz,increasing by about1400%.This work may enable a new strategy to boost the bandwidth and output power of TENG through nonlinear oscillators.展开更多
Primary alcohols are widely used in industry as solvents and precursors of detergents.The classic methods for hydration of terminal alkenes always produce the Markovnikov products.Herein,we reported a reliable approac...Primary alcohols are widely used in industry as solvents and precursors of detergents.The classic methods for hydration of terminal alkenes always produce the Markovnikov products.Herein,we reported a reliable approach to produce primary alcohols from terminal alkenes combining with biomass-derived allyl alcohol by tandem cross-metathesis/hydrogenation.A series of primary alcohol with different chain lengths was successfully produced in high yields(ca.90%).Computational studies revealed that self-metathesis and hydrogenation of substrates are accessible but much slower than crossmetathesis.This new methodology represents a unique alternative to primary alcohols from terminal alkenes.展开更多
The Bloom helicase （BLM） gene product encodes a DNA helicase that functions in homologous recombination repair to prevent genomic instability. BLM is highly active in binding and unfolding G-quadruplexes （G4）, whi...The Bloom helicase （BLM） gene product encodes a DNA helicase that functions in homologous recombination repair to prevent genomic instability. BLM is highly active in binding and unfolding G-quadruplexes （G4）, which are non- canonical DNA structures formed by Hoogsteen base-pairing in guanine-rich sequences. Here we use single-molecule fluorescence resonance energy transfer （smFRET） to study the molecular mechanism of BLM-catalysed G4 unfolding and show that BLM unfolds G4 in two pathways. Our data enable us to propose a model in which the HRDC domain functions as a regulator of BLM, depending on the position of the HRDC domain of BLM in action： when HRDC binds to the G4 sequence, BLM may hold G4 in the unfolded state; otherwise, it may remain on the unfolded G4 transiently so that G4 can refold immediately.展开更多
基金This work was supported by National Natural Science Foundation of China.(No.82170960,81870769,51973243,52173150 and 82201098)Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110379 and 2021A1515010782)the Shenzhen Basic Research Project(JCYJ20190807155801657).
文摘Recent evidence highlights multifaceted biological needs to recapitulate the bone microenvironment for bone regeneration.Neurotization has great potential for realizing multi-system modulations in bone tissue engineering(BTE).However,a neural strategy involving all the key bone repair steps temporally has not yet been reported.In this study,we reported the neural tissue engineering hydrogel-encapsulated Schwann cell-derived exosomes(SC Exo).This sustained-release SC Exo system prominently enhanced bone regeneration by promoting innervation,immunoregulation,vascularization,and osteogenesis in vivo.Moreover,the in vitro results further confirmed that this system significantly induced M2 polarization of macrophages,tube formation of HUVECs,and BMSCs osteogenic differentiation.Furthermore,BMSCs osteogenesis was promoted by upregulating the TGF-β1/SMAD2/3 signaling pathway.In summary,a novel cell-free and easily prepared SC Exo neural engineering was successfully developed to promote bone regeneration by orchestrating the entire bone healing microenvironment,which may provide a new strategy for tissue engineering and clinical treatment of bone defects.
文摘The vigorous expansion of renewable energy as a substitute for fossil energy is the predominant route of action to achieve worldwide carbon neutrality. However, clean energy supplies in multi-energy building districts are still at the preliminary stages for energy paradigm transitions. In particular, technologies and methodologies for large-scale renewable energy integrations are still not sufficiently sophisticated, in terms of intelligent control management. Artificial intelligent (AI) techniques powered renewable energy systems can learn from bioinspired lessons and provide power systems with intelligence. However, there are few in-depth dissections and deliberations on the roles of AI techniques for large-scale integrations of renewable energy and decarbonisation in multi-energy systems. This study summarizes the commonly used AI-related approaches and discusses their functional advantages when being applied in various renewable energy sectors, as well as their functional contribution to optimizing the operational control modalities of renewable energy and improving the overall operational effectiveness. This study also presents practical applications of various AI techniques in large-scale renewable energy integration systems, and analyzes their effectiveness through theoretical explanations and diverse case studies. In addition, this study introduces limitations and challenges associated with the large-scale renewable energy integrations for carbon neutrality transition using relevant AI techniques, and proposes further promising research perspectives and recommendations. This comprehensive review ignites advanced AI techniques for large-scale renewable integrations and provides valuable informational instructions and guidelines to different stakeholders (e.g., engineers, designers and scientists) for carbon neutrality transition.
基金supported by the National Key R&D Plan of China(No.2022YFC3602904)the National Natural Science Foundation of China(Nos.81974395,82173036)+11 种基金Guangdong Basic and Applied Basic Research Foundation(No.2019A1515011437)International Science and Technology Cooperation Project Plan of Guangdong Province(No.2021A0505030085)Sun Yat-Sen University Clinical Research 5010 Program(No.2019005)Beijing Bethune Charitable Foundation(No.mnzl202001)Guangzhou Science and Technology Key R&D Project(No.202206010117)Beijing CSCO Clinical Oncology Research Foundation(Nos.Ytongshu2021/ms-0162,Y-MSDZD2022-0760)Guangdong Province Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation(No.2020B1212060018OF006)Guangdong Provincial Clinical Research Center for Urological Diseases(No.2020B1111170006)supported by the National Natural Science Foundation of China(Nos.52173150,51973243)supported by the National Natural Science Foundation of China(No.82173088)Natural Science Foundation of Guangdong(No.2022A1515012383)the Guangzhou Science and Technology Fund(No.A202201011299)
文摘Traditional therapies such as surgery and endocrine therapy no longer meet the clinical needs in prostate cancer treatment,and more effective treatments are urgently required.Recent studies have reported that targeted inhibition of the transcription factor cyclin dependent kinase 7(CDK7)could effectively suppress prostate cancer progression.However,the toxicity of CDK7 inhibitors such as THZ1 is the main limitation of the clinical application.In this work,we synthesized Cys8E(C8E)nanoparticles(NPs)loaded with THZ1(C8E@THZ1),a novel GSH-targeting and stimuli-responsive nano-delivery platform,and investigated its anti-tumor potential and biosafety properties.In vitro,C8E@THZ1 potently inhibited the proliferation and promoted the apoptosis of prostate cancer cells.On tumor-bearing mice,C8E@THZ1 inhibited tumors by up to 85%,while the damage of THZ1 to liver function was effectively avoided.These results confirmed that inhibition of CDK7 can effectively block the progression of prostate cancer,and that Cys8E NPs is a highly prospective delivery platform to promote the clinical application of CDK7 inhibitors.
基金supported by the National Natural Science Foundation of China(Nos.62035006 and U2033204)the Guangdong Outstanding Scientific Innovation Foundation(No.2019TX05X383)+2 种基金the Program of Marine Economy Development Special Fund under Department of Natural Resources of Guangdong Province(No.GDNRC[2023]23)J.H.is indebted to National Natural Science Foundation of China(No.52207230)Guangzhou Municipal Science and Technology Project(Nos.2023A03J0003 and 2023A03J0103).
文摘Lithium(Li)dendrite growth significantly deteriorates the performance and shortens the operation life of lithium metal batteries.Capturing the intricate dynamics of surface localized and rapid mass transport at the electrolyte–electrode interface of lithium metal is essential for the understanding of the dendrite growth process,and the evaluation of the solutions mitigating the dendrite growth issue.Here we demonstrate an approach based on an ultrasensitive tilted fiber Bragg grating(TFBG)sensor which is inserted close to the electrode surface in a working lithium metal battery,without disturbing its operation.Thanks to the superfine optical resonances of the TFBG,in situ and rapid monitoring of mass transport kinetics and lithium dendrite growth at the nanoscale interface of lithium anodes have been achieved.Reliable correlations between the performance of different natural/artificial solid electrolyte interphases(SEIs)and the time-resolved optical responses have been observed and quantified,enabling us to link the nanoscale ion and SEI behavior with the macroscopic battery performance.This new operando tool will provide additional capabilities for parametrization of the batteries’electrochemistry and help identify the optimal interphases of lithium metal batteries to enhance battery performance and its safety.
基金HKSAR Research Grants Council,Grant/Award Numbers:16305320,C6014-20W,16307020,14200120National Natural Science Foundation of China,Grant/Award Numbers:21788102,52275560+3 种基金Guangdong Natural Science Funds for Distinguished Young Scholar,Grant/Award Number:2023B1515020074Innovation and Technology Commission,Grant/Award Number:ITCCNERC14SC01the start-up fund of Hong Kong University of Science and Technology(Guangzhou),Grant/Award Number:G0101000092the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone,Grant/Award Number:HZQB-KCZYB-2020083。
文摘Visible light-based human–machine interactive media is capable of transmitting electrical readouts to machines and providing intuitive feedback to users simultaneously.Currently,many inorganic mechanoluminescent(ML)materials-based interactive media,typically ZnS-loaded phosphors(ZLPs),have been successfully demonstrated.However,organic ML materials-based solutions were rarely exploited despite their huge merits of strong structural modification,abundant luminescence property,low cost,easy preparation,and so on.Here,we propose a novel interactive tactile display(ITD)based on organic ML materials(Cz-A6-dye)and triboelectric nanogenerator,with ultra-brightness(130%enhancement)and ultra-low threshold pressure(57%reduction)as compared to ZLPs.The proposed ITD achieves the conversion of weak mechanical stimuli into visible light and electrical signals simultaneously,without extra power supplies.Furthermore,the relationship between the luminous performance of organic ML materials and mechanical force is quantified,benefiting from the uniform ML layer prepared.Enabled by convolutional neural networks,the high-accuracy recognition(97.1%)for handwriting and identity of users is realized at the same time.Thus,the ITD has great potential for intelligent wearable electronics and classified military applications.
基金the National Key Research and Development Program of China(No.2022YFA1103302)the National Natural Science Foundation of China(Nos.92268205,52173150,51973243,82204287)+2 种基金Guangdong Innovative and Entrepreneurial Research Team Program(No.2019ZT08Y485)Guangdong Basic and Applied Basic Research Foundation(No.2021B1515020012)Guangzhou Science and Technology Program City-University Joint Funding Project(No.2023A03J0001).
文摘Macrophages,as a subset of innate immune cells,play a pivotal role in the initiation,maintenance,and resolution of inflammatory responses during tissue damage repair,defense against infections,and tumor progression.However,the mechanisms by which macrophages regulate inflammation in acute myeloid leukemia(AML)and their involvement in the chemotherapeutic effect remain elusive.In this study,we have identified that AML cells stimulate macrophage expansion by activating the colony-stimulating factor 1 receptor(CSF1R)pathway.The expanded macrophages activate nuclear factor kappa-B(NFκB)to induce the expression of inflammatory factors,thereby maintaining leukemic cell quiescence and promoting cell survival following chemotherapy.Furthermore,we have successfully utilized a poly(ferulic acid)nanocarrier to selectively target macrophages for inhibiting the NFκB-mediated inflammation,ultimately enhancing chemotherapy efficacy against AML.Taken together,our findings highlight the crucial role of macrophage-induced inflammation in conferring chemoresistance to AML,and demonstrate the potential of a targeted nanocarrier specifically designed for inflammatory macrophages to improve the AML chemotherapeutic outcomes.
基金supported by grants from Science and Technology Program of Guangzhou,China(No.201804010146)Guangzhou Science and Technology Program City-University Joint Funding Project(No.2023A03J0001)。
文摘Enhancing the active tumor targeting ability and decreasing the clearance of reticuloendothelial system(RES)are important issues for drug delivery systems(DDSs)in cancer therapy.In recent years,cell membrane camouflage,as one of the biomimetic modification strategies,has shown huge potential.Many natural properties of source cells can be inherited,allowing the DDSs to successfully avoid phagocytosis by macrophages,prolong circulation time,and achieve homologous targeting to lesion tissue.In this study,a cancer cell membrane camouflaged nanoplatform based on gelatin with a typical core-shell structure was developed for cancer chemotherapy.Doxorubicin(DOX)loaded gelatin nanogel(NG@DOX)acted as the inner core,and 4T1(mouse breast carcinoma cell)membrane was set as the outer shell(M-NG@DOX).The M-NG platform enhanced the ability of homologous targeting due to the surface protein of cell membrane being completely retained,which could promote the cell uptake of homotypic cells,avoid phagocytosis by RAW264.7 macrophages,and therefore increase accumulation in tumor tissue.Meanwhile,due to the better controlled drug release capability of M-NG@DOX,premature release of DOX in circulation could be reduced,minimizing side effects in common chemotherapy.As a result,the biomimetic nanoplatform in this study,obtained by a cancer cell membrane camouflaged drug delivery system,efficiently reached desirable tumor elimination,providing a significant strategy for effective targeted therapy and specific carcinoma therapy.
基金support of the National Natural Science Foundation of China(Nos.52173150,52073313)the Guangzhou Science and Technology Program City-University Joint Funding Project(No.2023A03J0001)the Shenzhen Science and Technology Program(No.KCXFZ 202002011010232)。
文摘Colorectal cancer is a common cancer worldwide.Traditional chemotherapeutic drugs often face limitations such as poor aqueous solubility and high systemic toxicity,which can lead to adverse side effects and limited therapeutic efficacy.In this study,a library of one kind of biodegradable and biocompatible polymer,leucine based-poly(ester amide)s(Leu-PEAs)was developed and utilized as drug carrier.The structure of Leu-PEAs can be tuned to alter their physicochemical properties,enhancing drug loading capacity and delivery efficiency.Leu-PEAs can self-assemble into nanoparticles by nanoprecipitation and load paclitaxel(PTX)with the diameter of~108 nm and PTX loading capacity of~8.5%.PTX-loaded Leu-PEAs nanoparticles(PTX@Leu-PEAs)demonstrated significant inhibition of CT26 cell growth in vitro.In vivo,these nanoparticles exhibited prolonged tumor accumulation and antitumor effects,with no observed toxicity to normal organs.Furthermore,blank Leu-PEAs nanoparticles also showed antitumor effects in vitro and in vivo,which may be attributed to the activation of the mammalian target of rapamycin(m TOR)pathway by leucine.Consequently,this biocompatible Leu-PEAs nano-drug delivery system shows potential as a promising strategy for colorectal cancer treatment,warranting further investigation.
基金supported by grants from the National Natural Science Foundation of China(Grant No.82170960 and No.52173150)the Science and Technology Program of Guangzhou,China(Grant No.202206080009)+1 种基金Guangzhou Science and Technology Program City-University Joint Funding Project(Grant No.2023A03J0001)China Postdoctoral Science Foundation(Grant No.2022M723670).
文摘Oxidative stress and inflammation are key drivers of osteoarthritis(OA)pathogenesis and disease progression.Herein we report the synthesis of poly(p-coumaric)nanoparticles(PCA NPs)from p-courmaic acid(p-CA),a naturally occurring phytophenolic acid,to be a multifunctional and drug-free therapeutic for temporomandibular joint osteoarthritis(TMJOA).Compared to hyaluronic acid(HA)that is clinically given as viscosupplementation,PCA NPs exhibited long-term efficacy,superior anti-oxidant and anti-inflammatory properties in alleviating TMJOA and repairing the TMJ cartilage and subchondral bone in a rat model of TMJOA.Notably,TMJ repair mediated by PCA NPs could be attributed to their anti-oxidant and anti-inflammatory properties in enhancing cell proliferation and matrix synthesis,while reducing inflammation,oxidative stress,matrix degradation,and chondrocyte ferroptosis.Overall,our study demonstrates a multifunctional nanoparticle,synthesized from natural p-coumaric acid,that is stable and possess potent antioxidant,anti-inflammatory properties and ferroptosis inhibition,beneficial for treatment of TMJOA.
基金This study was supported by Basic Research Project from Jiangmen Science and Technology Bureau(Grant No.2220002000356)China University of Petroleum(Beijing)(Grand No.2462023BJRC007)The Guangdong Basic and Applied Basic Research Foundation(No.2022A1515110376).
文摘In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture network.It has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture communication.In addition,most of the existing models are solved analytically based on Laplace transform and numerical inversion.Hence,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix depletion.To simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the microfractures.Then,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by integration.Finally,a relationship between oil rate and production time in real-time space is obtained.The new model is verified against classical analytical models.When the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,respectively.Certainly,the new model also has an excellent agreement with the numerical model.The model is then applied to two actual tight oil wells completed in western Canada sedimentary basin.After identifying the flow regime,the solution suitably matches the field production data,and the model parameters are determined.Through these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.
基金The Science and Technology Planning Projects of Guangdong Province(Grant No.2018B010109008)National Key R&D Program of China(Grant No.2018YFC0116500).
文摘In recent years,the incidence of myopia has increased at an alarming rate among children and adolescents in China.The exploration of an effective prevention and control method for myopia is in urgent need.With the development of information technology in the past decade,artificial intelligence with the Internet of Things technology(AIoT)is characterized by strong computing power,advanced algorithm,continuous monitoring,and accurate prediction of long-term progression.Therefore,big data and artificial intelligence technology have the potential to be applied to data mining of myopia etiology and prediction of myopia occurrence and development.More recently,there has been a growing recognition that myopia study involving AIoT needs to undergo a rigorous evaluation to demonstrate robust results.
基金This work was supported by the National Natural Science Foundation of China(No.51973243)Fundamental Research Funds for the Central Universities(No.191gzd35)+2 种基金Guangdong Innovative and Entrepreneurial Research Team Program(No.2016ZT06S029)Shenzhen Basic Research Project(No.JCYJ20190807155801657)Key international(regional)cooperative research projects of the National Natural Science Foundation of China(No.5181001045).
文摘High oxidative stress injury and bacterial infection are the main challenges that impair wound healing in diabetic patients.Therefore,a hydrogel with enhanced antimicrobial and antioxidant properties was developed for rapid healing of diabetic wounds.In this study,chitosan methacrylate-gallic acid(CSMA-GA)polymer with antioxidant activity,antimicrobial activity,and ultraviolet(UV)-triggered gelling properties was developed as a hydrogel precursor.Meanwhile,amphiphilic Pluronic F127 molecules were used to load hydrophobic chlorhexidine drug molecules to obtain F127/chlorhexidine nanoparticle(NP)with strong antibacterial activity.Subsequently,F127/chlorhexidine NPs were encapsulated in CSMA-GA hydrogel to further enhance its antibacterial activity.The hybrid hydrogel platform(CSMA-GA/F127/chlorhexidine(CMGFC))exhibited high antibacterial efficiency(>99.9%)and strong reactive oxygen species(ROS)scavenging ability(>80.0%),which effectively protected cells from external oxidative stress(upregulated superoxide dismutase(SOD)and glutathione/oxidized glutathione disulfide(GSH/GSSG)levels and downregulated malondialdehyde(MDA)levels).Moreover,in vivo results proved that the CMGFC hydrogel significantly reduced inflammatory responses(downregulated interleukin-6(IL-6)and upregulated interleukin-10(IL-10)levels),promoted angiogenesis(upregulated vascular endothelial growth factor(VEGF)and platelet endothelial cell adhesion molecule-1(CD 31)levels),and wound healing(enhanced collagen deposition and tissue remodelling).Overall,the CMGFC hydrogel with enhanced antimicrobial and antioxidant properties demonstrated significant potential to enhance diabetic wound healing.
基金the support from the National Natural Science Foundation of China (Nos.21773314, 21720102007,21821003 and 21890382)the Guangdong Natural Science Funds for Distinguished Young Scholar (No. 2019B151502017)+3 种基金the Tip-top Youth Talents of Guangdong special support program (No.20173100042150021)Science and Technology Planning Project of Guangzhou (No.201707010168)the General Financial Grant from the China Postdoctoral Science Foundation (No.2019M662809)Local Innovative and Research Teams Project of Guangdong Peal River Talents Program (No.2017BT01C161)。
文摘Reliable technologies for CO_(2) capture and conversion(C3) are of vital importance for the establishment of a sustainable society.Metal-organic framework(MOF) composites have shown their compelling potentials for C3 due to the plentiful reticular chemistry of MOF structures and the synergistic catalysis between MOFs and the functional guests.This review focuses on the syntheses and catalytic applications towards C3 of MOF composites,which is divided into three sections.The first section gives a brief introduction about synthetic strategies of MOF composites.The second section discusses the recent progress of MOF composites in C3,including CO_(2) chemical fixation,hydrogenation,photoreduction,electro reduction and photoelectro reduction.The third section summarizes the challenges and future prospects of MOF composites for C3.We hope that this review cannot only provide an inspiration for the rational design of MOF composites for C3,but also stimulate more and more research works in this emerging area.
基金Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)Hong Kong Research Grant Council(Aoe/E-603/18)。
文摘The long-term trends in the occurrence frequency of pre-summer daytime and nocturnal extreme hourly rainfall(EXHR) during 1988-2018 in Hong Kong and their spatial distributions are examined and analyzed. Despite a significant increasing trend observed in the occurrence frequency of pre-summer EXHRs during the investigated period,the increase in daytime and nocturnal EXHRs show distinct spatial patterns. Nocturnal EXHRs show uniform increasing trends over the entire Hong Kong. However, the increase in daytime EXHRs is concentrated over the northern or eastern areas of Hong Kong, indicating a downstream shift of pre-summer EXHRs in Hong Kong with regard to the prevailing southwesterly monsoonal flows in south China. The clustering of weather types associated with daytime and nocturnal EXHRs further reveals that the increase in EXHRs over Hong Kong are mainly contributed by the increase of the events associated with southwesterly monsoonal flows with relatively high speeds. During the past few decades, the southwesterly monsoonal flows at coastal south China have undergone a substantial weakening due to the increased surface roughness induced by the urbanization over the Guangdong-Hong Kong-Macao Greater Bay Area since 1990s,leading to enhanced low-level convergence and thus significant increase in EXHRs at coastal south China. Meanwhile,daytime sea-wind circulation at coastal south China is markedly enhanced during the investigated period, which is the main reason for the northward shift of daytime EXHRs in Hong Kong. In addition, the blocked southwesterly monsoonal flows at coastal south China are detoured eastward, leading to stronger convergence and increase in EXHRs at eastern coast of Hong Kong, especially during daytime, when the easterly sea winds prevail at the region.
基金financial supports from the Zhejiang Normal University(YS304320035)the Natural Science Foundation of China(21603039)。
文摘Supported nickel catalysts are promising candidates for dry reforming of methane, but agglomeration of Ni^(0) and coke deposition hinder the industrial applications. Herein, we report a novel interface-directed synthetic approach to construct distinct metal ensembles by carefully tuning the compositions of the carriers. A Zr-Mn-Zn ternary oxide-supported Ni catalyst, together with the respective binary oxide-supported analogues, was synthesized by adopting a sequential co-precipitation and wetness impregnation method. Combined characterization techniques identify distinct catalyst models, including (i) conventional NiO nanoparticles with different sizes on Zr-Mn and Zr-Zn, and (ii) epitaxially growing NiO ensembles of a few nanometers thickness at the periphery of ZnO_(x) particles. These catalysts exhibit divergent responses in the catalytic testing, with the ternary oxide system significantly outperforming the binary analogues. The strong electronic interactions between Mn-Ni increase Ni dispersion and the activity while the stability is strengthened upon Zn addition. Both high activity, high selectivity, and remarkable stability are attained upon co-adding Mn and Zn. The interfaces between Ni and Zr-Mn-Zn rather than the physical contacts of individual oxide-supported analogues through mechanical mixing are keys for the outstanding performance.
基金Thanks to the following fund projects for their support to this work:National Natural Science Foundation of China(Nos.51973243 and 52173150)International Cooperation and Exchange of the National Natural Science Foundation of China(No.51820105004)Shenzhen Basic Research Project(No.JCYJ20190807155801657).
文摘As a representative of chronic wounds,the long-term high levels of oxidative stress and blood sugar in chronic diabetic wounds lead to serious complications,making them the biggest challenge in the research on wound healing.Many edible natural biomaterials rich in terpenes,phenols,and flavonoids can act as efficient antioxidants.In this study,okra extract was selected as the main component of a wound dressing.The okra extracts obtained via different methods comprehensively maintained the bioactivity of multiple molecules.The robust antioxidant properties of okra significantly reduced intracellular reactive oxygen species production,thereby accelerating the wound healing process.The results showed that okra extracts and their hydrogel dressings increased cell migration,angiogenesis,and re-epithelization of the chronic wound area,considerably promoting wound remodeling in diabetic rats.Therefore,okra-based hydrogels are promising candidates for skin regeneration and wider tissue engineering applications.
基金This work was supported by HKSAR,the Research Grants Council Early Career Scheme(Grant No.24206919)the Guangdong Basic and Applied Basic Research Foundation(Project No.2020A1515111161)This work was supported in part by the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone(HZQB-KCZYB-2020083).
文摘Triboelectric nanogenerators(TENGs)represent a promising next‐generation renewable energy technology.TENGs have become increasingly popular for harvesting vibration energy in the environment due to their advantages of lightweight,broad range of material choices,low cost,and no pollution.However,issues such as input force irregularity,working bandwidth,efficiency calculation,and dynamic modeling hinder the use of TENGs in industrial or practical applications.In this paper,the modeling process of the dynamical system of a TENG is reviewed from the perspective of energy flow.In addition,this paper reviews the main contributions made in recent years to achieve optimized output based on springs,magnetic forces,and pendulums,and introduces different ways to increase the bandwidth of TENGs.Finally,the main problems of TENGs in the process of harvesting vibration energy are discussed.This review may serve as a practical reference for methods to convert irregular mechanical input sources into optimized output performance toward the commercialization of TENGs.
基金supported by HKSAR the Research Grants Council Early Career Scheme(Grant No.24206919)Guangdong Basic and Applied Basic Research Foundation(Project No.2020A1515111161)This work was supported in part by the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone(HZQB-KCZYB-2020083).
文摘A narrow resonance bandwidth of an energy harvesters limits its response to the wide frequency spectrum in ambient environ-ments.This work proposes an addition of a nonlinear restoring force applied to a triboelectric nanogenerator(TENG)to tune and broaden the resonance bandwidth.This restoring force is applied by permanent magnets at both sides of the slider and two external magnets.The noncontact strategy is adopted between the slider and the grating electrodes to avoid the wear of electrodes and energy loss caused by friction.The results show that compared with the linear system,the nonlinear noncontact TENG(NN-TENG)can increase the peak current from 6.3μA to 7.89μA,with an increment of about 25%,increase the peak power from 650μW to 977μW,increasing by about 50%,and increase the bandwidth from 0.5 Hz to 7.75 Hz,increasing by about1400%.This work may enable a new strategy to boost the bandwidth and output power of TENG through nonlinear oscillators.
基金financially supported by the National Natural Science Foundation of China(Nos.21322608 and 21276174)the Natural Science Foundation of Shanxi Province(No.201801D121055)Program for the Shanxi Young Sanjin Scholar。
文摘Primary alcohols are widely used in industry as solvents and precursors of detergents.The classic methods for hydration of terminal alkenes always produce the Markovnikov products.Herein,we reported a reliable approach to produce primary alcohols from terminal alkenes combining with biomass-derived allyl alcohol by tandem cross-metathesis/hydrogenation.A series of primary alcohol with different chain lengths was successfully produced in high yields(ca.90%).Computational studies revealed that self-metathesis and hydrogenation of substrates are accessible but much slower than crossmetathesis.This new methodology represents a unique alternative to primary alcohols from terminal alkenes.
基金supported by the National Natural Science Foundation of China(Grant Nos.11674382,11574381,and 11574382)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZDJ-SSW-SYS014)
文摘The Bloom helicase （BLM） gene product encodes a DNA helicase that functions in homologous recombination repair to prevent genomic instability. BLM is highly active in binding and unfolding G-quadruplexes （G4）, which are non- canonical DNA structures formed by Hoogsteen base-pairing in guanine-rich sequences. Here we use single-molecule fluorescence resonance energy transfer （smFRET） to study the molecular mechanism of BLM-catalysed G4 unfolding and show that BLM unfolds G4 in two pathways. Our data enable us to propose a model in which the HRDC domain functions as a regulator of BLM, depending on the position of the HRDC domain of BLM in action： when HRDC binds to the G4 sequence, BLM may hold G4 in the unfolded state; otherwise, it may remain on the unfolded G4 transiently so that G4 can refold immediately.
