DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinl...DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinling Mountains of China.展开更多
BACKGROUND Persistent left superior vena cava(PLSVC),a relatively rare thoracic vascular malformation,can inconvenience perfusionists and operators when encountered during deep hypothermic circulatory arrest(DHCA).CAS...BACKGROUND Persistent left superior vena cava(PLSVC),a relatively rare thoracic vascular malformation,can inconvenience perfusionists and operators when encountered during deep hypothermic circulatory arrest(DHCA).CASE SUMMARY Herein,we describe the case of a patient with concurrent giant aortic arch aneurysm,aortic stenosis,and PLSVC.To treat these conditions,we performed right hemiarch and aortic valve replacements under DHCA.Notably,we applied“bilateral superior vena cava retrograde cerebral perfusion(RCP)”for cerebral protection,which significantly optimized the surgical procedure and reduced the risk of postoperative complications.The patient was discharged 14 d after surgery with no complications.CONCLUSION Surgical intervention for PLSVC under DHCA can be performed using the bilateral superior vena cava RCP approach.展开更多
Endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)are well-established therapeutics for gastrointestinal neoplasias,but complications after EMR/ESD,including bleeding and perforation,result in ...Endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)are well-established therapeutics for gastrointestinal neoplasias,but complications after EMR/ESD,including bleeding and perforation,result in additional treatment morbidity and even threaten the lives of patients.Thus,designing biomaterials to treat gastric bleeding and wound healing after endoscopic treatment is highly desired and remains a challenge.Herein,a series of injectable pH-responsive selfhealing adhesive hydrogels based on acryloyl-6-aminocaproic acid(AA)and AA-g-N-hydroxysuccinimide(AA-NHS)were developed,and their great potential as endoscopic sprayable bioadhesive materials to efficiently stop hemorrhage and promote the wound healing process was further demonstrated in a swine gastric hemorrhage/wound model.The hydrogels showed a suitable gelation time,an autonomous and efficient self-healing capacity,hemostatic properties,and good biocompatibility.With the introduction of AA-NHS as a micro-cross-linker,the hydrogels exhibited enhanced adhesive strength.A swine gastric hemorrhage in vivo model demonstrated that the hydrogels showed good hemostatic performance by stopping acute arterial bleeding and preventing delayed bleeding.A gastric wound model indicated that the hydrogels showed excellent treatment effects with significantly enhanced wound healing with type I collagen deposition,α-SMA expression,and blood vessel formation.These injectable self-healing adhesive hydrogels exhibited great potential to treat gastric wounds after endoscopic treatment.展开更多
The WC/CoCrFeNiAl0.2 high-entropy alloy(HEA)composites were prepared through high-gravity combustion synthesis.The preparation method is presented below.First,using a designed suitable multiphase thermite system,the m...The WC/CoCrFeNiAl0.2 high-entropy alloy(HEA)composites were prepared through high-gravity combustion synthesis.The preparation method is presented below.First,using a designed suitable multiphase thermite system,the molten CoCrFeNiAl0.2 HEA was fabricated using low-cost metal oxides.The molten HEA was subsequently infiltrated into the WC layer to fabricate WC/CoCrFeNiAl0.2 composites in a highgravity field.The porosity of the WC/CoCrFeNiAl0.2 composites was down-regulated,and their compressive yield strength was up-regulated when the high-gravity field was increased from 600g to 1500g because this infiltration process of a HEA melt into the WC layer is driven by centrifugal force.The WC particles in the composites exhibited a gradient distribution along the direction of the centrifugal force,which was attributed to the combined action of the high-gravity field and the temperature gradient field.The Vickers hardness of the sample was down-regulated from 9.53 to 7.41 GPa along the direction of the centrifugal force.展开更多
Zinc oxide(ZnO) thin films were deposited onto different substrates — tin-doped indium oxide(ITO)/glass, ITO/polyethylene naphthalate(PEN), ITO/polyethylene terephthalate(PET) — by the radio-frequency(RF) magnetron ...Zinc oxide(ZnO) thin films were deposited onto different substrates — tin-doped indium oxide(ITO)/glass, ITO/polyethylene naphthalate(PEN), ITO/polyethylene terephthalate(PET) — by the radio-frequency(RF) magnetron sputtering method. The effect of various O2/(Ar+O2) gas flow ratios(0, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6) was studied in detail. ZnO layers deposited onto ITO/PEN and ITO/PET substrates exhibited a stronger c-axis preferred orientation along the(0002) direction compared to ZnO deposited onto ITO/glass. The transmittance spectra of ZnO films showed that the maximum transmittances of ZnO films deposited onto ITO/glass, ITO/PEN, and ITO/PET substrates were 89.2%, 65.0%, and 77.8%, respectively. Scanning electron microscopy(SEM) images of the film surfaces indicated that the grain was uniform. The cross-sectional SEM images showed that the ZnO films were columnar structures whose c-axis was perpendicular to the film surface. The test results for a fabricated ZnO thin film based energy harvester showed that its output voltage increased with increasing acceleration of external vibration.展开更多
DEAR EDITOR, Despite the vulnerability of primates to the negative impacts of human activities and climate change, there is still room for optimism. Notably, years of conservation efforts may have paid off for the gol...DEAR EDITOR, Despite the vulnerability of primates to the negative impacts of human activities and climate change, there is still room for optimism. Notably, years of conservation efforts may have paid off for the golden snub-nosed monkey(Rhinopithecus roxellana). Our field surveys confirmed the existence of 188 to 220 wild multilevel societies(MLS) of R. roxellana, with an estimated 22 710 to 26 130 individuals in 2019。展开更多
We consider a bistable mesoscopic chemical reaction system and calculate entropy produc- tion along the dominant pathway during nonequilibrium phase transition. Using probability generating function method and eikonal...We consider a bistable mesoscopic chemical reaction system and calculate entropy produc- tion along the dominant pathway during nonequilibrium phase transition. Using probability generating function method and eikonal approximation, we first convert the chemical master equation into the classical Hamilton-Jacobi equation, and then find the dominant pathways between two steady states in the phase space by calculating zero-energy trajectories. We find that entropy productions are related to the actions of the forward and backward dominant pathways. At the coexistence point where the stabilities of the two steady states are equiv alent, both the system entropy change and the medium entropy change are zero; whereas at non-coexistence point both of them are nonzero.展开更多
Solid-state lithium batteries(SSLBs)solve safety issues and are potentially energy-dense alternatives to next-generation energy storage systems.Battery green recycling routes are responsible for the widespread use of ...Solid-state lithium batteries(SSLBs)solve safety issues and are potentially energy-dense alternatives to next-generation energy storage systems.Battery green recycling routes are responsible for the widespread use of SSLBs due to minimizing environmental contamination,reducing production costs,and providing a sustainable solution for resources,e.g.,saving rare earth elements(La,Ta,etc.).Herein,a solid-state recycling strategy is proposed to achieve green recycling of the crucial component solidstate electrolytes(SSEs)in spent SSLBs.The short-circuited garnet Li_(6.5)La_(3)Zr_(1.5)Ta_(0.5)O_(12)(LLZTO)is broken into fine particles and mixed with fresh particles to improve sintering activity and achieve high packing density.The continuous Li absorption process promotes sufficient grain fusion and guarantees the transformation from tetragonal phase to pure cubic phase for high-performance recycled LLZTO.The Li-ion conductivity reaches 5.80×10^(-4)S cm-1with a relative density of 95.9%.Symmetric Li cell with asrecycled LLZTO shows long-term cycling stability for 700 h at 0.3 mA cm^(-2)without any voltage hysteresis.Full cell exhibits an excellent cycling performance with a discharge capacity of 141.5 mA h g^(-1)and a capacity retention of 92.1%after 400 cycles(0.2C).This work develops an environmentally friendly and economically controllable strategy to recycle SSE from spent SSLBs,guiding future directions of SSLBs large-scale industrial application and green recycling study.展开更多
DEAR EDITOR,Movement patterns can reflect species-specific characteristics of individuals and animal groups at a given scale. Accurate three-dimensional(3D) assessment can quantify the relationship between movement pa...DEAR EDITOR,Movement patterns can reflect species-specific characteristics of individuals and animal groups at a given scale. Accurate three-dimensional(3D) assessment can quantify the relationship between movement patterns of an animal and its unique habitat. Here, we evaluated the effects of habitat structure on movement patterns of the golden snub-nosed monkey(Rhinopithecus roxellana). We used airborne light detection and ranging(LiDAR) to map the 3D structure of the temperate forest in the Qinling Mountains(Shaanxi, China).展开更多
The rational design of green chemical,low-cost,and highly efficient solid-state electrolytes for Li-metal anode is a promising but still challenging strategy for preventing Li dendrite growth and developing safe and u...The rational design of green chemical,low-cost,and highly efficient solid-state electrolytes for Li-metal anode is a promising but still challenging strategy for preventing Li dendrite growth and developing safe and ultralong cycle life Li-metal batteries.Herein,a homogeneous composite solid polymer electrolyte(CSPE)is fabricated with water as the ideal dispersion medium,hectorite(Ht)as nanofiller,and poly(ethylene oxide)(PEO)as the matrix,to guide uniform Li plating/stripping.Benefiting from the merit of Ht can form uniformly dispersed nanosheets in water,the obtained CSPE inheres to a low melting point,robust mechanical property,and high Li^(+)transference number.Moreover,the fabricated Li symmetric battery using PEO-Ht-LiClO_(4)CSPE keeps cycling steadily for 4000 h.The well demonstrated water-based CSPE paves the way for developing low-cost,environmentally friendly,and safe solid-state electrolytes for Li-metal batteries.展开更多
To solve the problem of high photogenerated carrier recombination rate and low photoelectric conversion efficiency of TiO_(2)-based materials,a simple N-doped anatase/rutile TiO_(2) heterophase nanorod film was design...To solve the problem of high photogenerated carrier recombination rate and low photoelectric conversion efficiency of TiO_(2)-based materials,a simple N-doped anatase/rutile TiO_(2) heterophase nanorod film was designed by a low-temperature hydrothermal method in this work.The enhanced separation and transport of photogenerated charges were facilitated by the smaller contact barrier and appropriate band matching between anatase TiO_(2)nanoparticles and rutile TiO_(2) nanorods.The introduction of N doping in anatase TiO_(2) resulted in an upward shift of the valence band and a narrowing of the band gap,consequently enhancing the efficiency of visible light utilization.The combination of the heterophase junction and N-doping exhibited a synergistic effect,effectively suppressing the recombination of photogenerated charges and enhancing the photoelectric conversion efficiency of the photoanode.Under AM 1.5G irradiation,the photocurrent density(J)of the A-TO(N)@R-TONR photoanode reached2.19 mA·cm^(-2)(V_(RHE,1.23 eV)).Additionally,the incident photon-electron conversion efficiency(IPCE)and the charge injection efficiency(η)reached 81.4%and 51.6%at320 nm.Furthermore,the J,IPCE,andηvalues of the A-TO(N)@R-TONR photoanode were 2.96,2.1 and 3.2times those of pure R-TONR photoanode,respectively.This work presents a rational strategy for designing efficient TiO_(2)-based photoanodes.展开更多
The Yellow River Basin is an important food production area and an ecological challenge for China, where environmental protection and water scarcity are the major constraints. For the upper reaches of the Yellow River...The Yellow River Basin is an important food production area and an ecological challenge for China, where environmental protection and water scarcity are the major constraints. For the upper reaches of the Yellow River Basin,optimizing the adoption of chemicals in agricultural production and integrating crops with livestock are the key strategies for protecting the eco-environment.For dryland agriculture in the middle and upper reaches, this study summarizes four aspects of efficient precipitation techniques in terms of collection,storage, conservation, and use, which have greatly improved crop yields and supported dryland crop production. Irrigated agriculture in the middle and lower reaches is the core area of China's grain production, where the area under water-saving irrigation reached 13.0 Mha in 2018, greatly improving water use. Compared with 1998, cereal production in 2018 increased by 62.2 Mt under similar total water withdrawals(49.7 billion to 51.6 billion m~3),and the annual soil erosion at the Tongguan Hydrological Observatory reduced by 584 million m~3 in 2018, achieving great success in environmental protection and efficient water use. The Chinese government has set a goal for the Yellow River Basin to become the national leader in environmental protection and efficient water use by 2035. Such a high demand requires the combined efforts of the whole community, as well as the adoption of new technologies,coordinated basin-wide development, and adequate policy support.展开更多
AIM:To investigate the role of endoplasmic reticulum(ER) stress in cancer radiotherapy and its molecular mechanism.METHODS:Tunicamycin(TM) was applied to induce ER stress in human esophageal cancer cell line EC109,and...AIM:To investigate the role of endoplasmic reticulum(ER) stress in cancer radiotherapy and its molecular mechanism.METHODS:Tunicamycin(TM) was applied to induce ER stress in human esophageal cancer cell line EC109,and the radiosensitization effects were detected by acute cell death and clonogenic survival assay.Cell cycle arrest induced by TM was determined by flow cytometric analysis after the cellular DNA content was labeled with propidium iodide.Apoptosis of EC109 cells induced by TM was detected by annexin V staining and Western blotting of caspase-3 and its substrate poly ADP-ribose polymerase.Autophagic response was determined by acridine orange(AO) staining and Western blotting of microtubule-associated protein-1 light chain-3(LC3) and autophagy related gene 5(ATG5).In order to test the biological function of autophagy,specific inhibitor or Beclin-1 knockdown was used to inhibit autophagy,and its effect on cell apoptosis was thus detected.Additionally,involvement of the phosphatidylinositol-3 kinase(PI3K)/Akt/mammalian target of the rapamycin(mTOR) pathway was also detected by Western blotting.Finally,male nude mice inoculated subcutaneously with EC109 cells were used to confirm cell model observations.RESULTS:Our results showed that TM treatment enhanced cell death and reduced the colony survival fraction induced by ionizing radiation(IR),which suggested an obvious radiosensitization effect of TM.Moreover,TM and IR combination treatment led to a significant increase of G2/M phase and apoptotic cells,compared with IR alone.We also observed an increase of AO positive cells,and the protein level of LC3-II and ATG5 was induced by TM treatment,which suggested an autophagic response in EC109 cells.However,inhibition of autophagy by using a chemical inhibitor or Beclin-1 silencing led to increased cell apoptosis and decreased cell viability,which suggested a cytoprotective role of autophagy in stressed EC109 cells.Furthermore,TM treatment also activated mTORC1,and in turn reduced Akt phosphorylation,which suggested the PI3K/Akt/mTOR signal pathway was involved in the TM-induced autophagic response in EC109 cells.Tumor xenograft results also showed synergistic retarded tumor growth by TM treatment and IR,as well as the involvement of the PI3K/Akt/mTOR pathway.CONCLUSION:Our data showed that TM treatment sensitized human esophageal cancer cells to radiation via apoptosis and autophagy both in vitro and in vivo.展开更多
Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal(GI)perforation management.However,several concerns remain for the existing bioadhesives including slow an...Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal(GI)perforation management.However,several concerns remain for the existing bioadhesives including slow and/or weak adhesive,poor mechanical strength,low biocompatibility,and poor biodegradability,which largely limit their clinical application in GI perforation repair.In this work,we introduce an in situ injectable Tetra-PEG hydrogel bioadhesive(SS)composed of tetra-armed poly(ethylene glycol)amine(Tetra-PEG-NH2)and tetra-armed poly(ethylene glycol)succinimidyl succinate(Tetra-PEG-SS)for the sutureless repair of GI defects.The SS hydrogel exhibits rapid gelation behavior and high burst pressure and is capable of providing instant robust adhesion and fluid-tight sealing in the ex vivo porcine intestinal and gastric models.Importantly,the succinyl ester linkers in the SS hydrogel endow the bioadhesive with suitable in vivo degradability to match the new GI tissue formation.The in vivo evaluation in the rat GI injured model further demonstrates the successful sutureless sealing and repair of the intestine and stomach by the SS hydrogel with the advantages of neglectable postsurgical adhesion,suppressed inflammation,and enhanced angiogenesis.Together,our results support potential clinical applications of the SS bioadhesive for the high-efficient repair of GI perforation.展开更多
Heptamethine cyanines(Cy7)are one of the most important dyes in bioimaging and phototherapy,but they often suffer from poor photostability or limited photothermal conversion efficiency.Here,a facile molecular engineer...Heptamethine cyanines(Cy7)are one of the most important dyes in bioimaging and phototherapy,but they often suffer from poor photostability or limited photothermal conversion efficiency.Here,a facile molecular engineering approach to regulating the photophysical properties of Cy7 by metal ions is demonstrated.By innovatively modifying the nitrogen with functional groups,a novel terpyridine-grafted nitrogen-terminated Cy7 scaffold(denoted as CydtPy)was synthesized and exhibited tunable photophysical properties when chelating with various metal ions(Mn^(2+),Fe^(2+),etc.).In comparison with metal-ion-free PEGylated CydtPy(LET-11),Mn^(2+)-chelated LET-11(namely,LET-11-Mn)exhibited the increased fluorescence emission intensity,and Fe^(2+)-chelated LET-11(namely,LET-11-Fe)showed the enhanced photostability with~2-fold increase in photothermal conversion efficiency.By simply switching the chelated metal ion species,LET-11-Mn or LET-11-Fe could be used for near-infrared fluorescence imaging,magnetic resonance imaging,or photoacoustic imaging.Furthermore,LET-11-Fe displayed superior synergistic efficacy of photothermal therapy and chemodynamic therapy both in vitro and in vivo.This work not only provides a new strategy for regulating the photophysical properties of cyanine dyes but also establishes a versatile nanoplatform for cancer theranostics.展开更多
Graphene quantum dots(GQDs)doped InGaO(IGO)thin film transistors(TFTs)have been fabricated based on solution-driven ZrO_(x) as gate dielectrics.Compare to pure IGO TFTs,superior electrical performance of the GQDs-IGO ...Graphene quantum dots(GQDs)doped InGaO(IGO)thin film transistors(TFTs)have been fabricated based on solution-driven ZrO_(x) as gate dielectrics.Compare to pure IGO TFTs,superior electrical performance of the GQDs-IGO TFTs can be achieved by adjusting the doping concentration.It has been demonstrated that GQDs-modified IGO TFTs devices with GQDs doping content of0.3 mg·ml^(-1)have the optimized performances,including field-effect mobility(μ_(FE))of 22.02 cm^(2)·V^(-1)·s^(-1),on/off current ratio(I_(on)/I_(off))of 7.06×10^(7),subthreshold swing(SS)of 0.09 V·dec^(-1),hysteresis of 0.04 V and interfacial trap states(D_(it))of 1.03×10^(12)cm^(-2).In addition,bias stress and illumination stress tests have been performed and excellent stability has been achieved for optimized GQDs-IGO-TFTs.The GQDs-IGO TFTs device showed smaller threshold voltage shift of 0.12 and 0.04 V under positive bias stress(PBS)test and negative bias stress(NBS)test for 3600 s,respectively.And it showed smaller threshold voltage shift of 0.27 and 0.34 V for red light under the PBS and NBS test for 3600 s,respectively.Meanwhile,it showed smaller threshold voltage shift of0.20 and 0.22 V for green light under PBS and NBS test for3600 s,respectively.It also showed smaller threshold voltage shift of 0.17 and 0.12 V for blue under the positive bias illumination stress(PBIS)test and negative bias illumination stress(NBIS)test for 3600 s,respectively.Lowfrequency noise(LFN)characteristics of GQDs-IGO/ZrO_(x)TFTs indicated that the noise source came from the fluctuations in mobility.Finally,a low voltage resistor-loaded unipolar inverter has been built based on GQDs-IGO/ZrO_(x)TFT,demonstrating good dynamic response behavior and a maximum gain of 7.4.These experimental results have suggested that solution-processed GQDs-IGO/ZrO_(x)TFT may envision potential applications in low-cost and large-area electronics.展开更多
Developing efficient photosensitizers for C-P bond construction is highly important and remains a challenge due to the urgently needed for the synthesis of modified nucleosides,nucleotides,and other phosphine-containi...Developing efficient photosensitizers for C-P bond construction is highly important and remains a challenge due to the urgently needed for the synthesis of modified nucleosides,nucleotides,and other phosphine-containing ligands.Herein,two pyrene-tethered bismoviologen derivatives(Py-BiV^(2+))were designed and synthesized for visible-light-induced C-P bonds formation.The photochemical and electrochemical properties of Py-BiV^(2+)were studied systemically,certifying fine-tunable opto-electronic properties through the number of pyrene groups(4,n=1;6,n=2).The prepared Py-BiV^(2+)showed strong light absorption,while retaining good redox features and chromic response features that were inherent to viologens.4 exhibited accelerated photoinduced electron transfer in the presence of the electron donor(pyrene)and the generated 4(radical cation)showed higher stability.Accordingly,Py-BiV^(2+)directly served as photosensitizers for the first time in the visible-light-induced C(sp^(3))-P and C(sp^(2))-P bonds formation.As expected,these novel viologen derivatives exhibited good catalytic performance and good substrate expansibility under ambient conditions.展开更多
基金supported by the National Natural Science Foundation of China (32070457, 32200396, 32000317)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31020302)+3 种基金Biodiversity Survey and Assessment Project(2019HJ2096001006)Key Cultivation Research Project of Shaanxi Academy of Sciences (2022k-05,2021kp-7,2020k-1,2020K-20)Forestry Reform and Development Foundation of Shaanxi Forestry Bureau (2021)American Society of Primatologists Wild “Saving Primates Where They Live” Partnership Award。
文摘DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinling Mountains of China.
基金Technology Innovation and Application Development Project of Chongqing,No.2021yc-cxfz30016.
文摘BACKGROUND Persistent left superior vena cava(PLSVC),a relatively rare thoracic vascular malformation,can inconvenience perfusionists and operators when encountered during deep hypothermic circulatory arrest(DHCA).CASE SUMMARY Herein,we describe the case of a patient with concurrent giant aortic arch aneurysm,aortic stenosis,and PLSVC.To treat these conditions,we performed right hemiarch and aortic valve replacements under DHCA.Notably,we applied“bilateral superior vena cava retrograde cerebral perfusion(RCP)”for cerebral protection,which significantly optimized the surgical procedure and reduced the risk of postoperative complications.The patient was discharged 14 d after surgery with no complications.CONCLUSION Surgical intervention for PLSVC under DHCA can be performed using the bilateral superior vena cava RCP approach.
基金This work was jointly supported by the National Natural Science Foundation of China(grant Nos.:51973172,51673155,81201927,82002957 and 81672460)the National Key Research and Development Plan of China(No.2018YFC0115300)+5 种基金the State Key Laboratory for Mechanical Behavior of Materials,the World-Class Universities(Disciplines)the Characteristic Development Guidance Funds for the Central Universities,the Natural Science Foundation of Shaanxi Province(No.2020JC-03 and 2019TD-020)the Innovation Talent Promotion Plan of Shaanxi(No.2017KJXX-07)the Key Research and Development Program of Shaanxi Province(No.2019SF-012)the Opening Project of Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research,College of Stomatology,Xi’an Jiaotong University(No.2019LHM-KFKT008)Fundamental Research Funds for the Central Universities of China(No.xjj2018090).
文摘Endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)are well-established therapeutics for gastrointestinal neoplasias,but complications after EMR/ESD,including bleeding and perforation,result in additional treatment morbidity and even threaten the lives of patients.Thus,designing biomaterials to treat gastric bleeding and wound healing after endoscopic treatment is highly desired and remains a challenge.Herein,a series of injectable pH-responsive selfhealing adhesive hydrogels based on acryloyl-6-aminocaproic acid(AA)and AA-g-N-hydroxysuccinimide(AA-NHS)were developed,and their great potential as endoscopic sprayable bioadhesive materials to efficiently stop hemorrhage and promote the wound healing process was further demonstrated in a swine gastric hemorrhage/wound model.The hydrogels showed a suitable gelation time,an autonomous and efficient self-healing capacity,hemostatic properties,and good biocompatibility.With the introduction of AA-NHS as a micro-cross-linker,the hydrogels exhibited enhanced adhesive strength.A swine gastric hemorrhage in vivo model demonstrated that the hydrogels showed good hemostatic performance by stopping acute arterial bleeding and preventing delayed bleeding.A gastric wound model indicated that the hydrogels showed excellent treatment effects with significantly enhanced wound healing with type I collagen deposition,α-SMA expression,and blood vessel formation.These injectable self-healing adhesive hydrogels exhibited great potential to treat gastric wounds after endoscopic treatment.
基金financially supported by the National Key R&D Program of China (No. 2017YFB0310303)the National Natural Science Foundation of China (No. 51702332)the Key Laboratory of Cryogenics, TIPC, CAS (Nos. CRYOQN201705 and CRYOQN201507)
文摘The WC/CoCrFeNiAl0.2 high-entropy alloy(HEA)composites were prepared through high-gravity combustion synthesis.The preparation method is presented below.First,using a designed suitable multiphase thermite system,the molten CoCrFeNiAl0.2 HEA was fabricated using low-cost metal oxides.The molten HEA was subsequently infiltrated into the WC layer to fabricate WC/CoCrFeNiAl0.2 composites in a highgravity field.The porosity of the WC/CoCrFeNiAl0.2 composites was down-regulated,and their compressive yield strength was up-regulated when the high-gravity field was increased from 600g to 1500g because this infiltration process of a HEA melt into the WC layer is driven by centrifugal force.The WC particles in the composites exhibited a gradient distribution along the direction of the centrifugal force,which was attributed to the combined action of the high-gravity field and the temperature gradient field.The Vickers hardness of the sample was down-regulated from 9.53 to 7.41 GPa along the direction of the centrifugal force.
基金supported by the National Natural Science Foundation of China (61671017)Anhui Provincial Natural Science Foundation (1508085ME72)the Provincial Natural Science Foundation of Anhui Higher Education Institution (KJ2016A787)
文摘Zinc oxide(ZnO) thin films were deposited onto different substrates — tin-doped indium oxide(ITO)/glass, ITO/polyethylene naphthalate(PEN), ITO/polyethylene terephthalate(PET) — by the radio-frequency(RF) magnetron sputtering method. The effect of various O2/(Ar+O2) gas flow ratios(0, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6) was studied in detail. ZnO layers deposited onto ITO/PEN and ITO/PET substrates exhibited a stronger c-axis preferred orientation along the(0002) direction compared to ZnO deposited onto ITO/glass. The transmittance spectra of ZnO films showed that the maximum transmittances of ZnO films deposited onto ITO/glass, ITO/PEN, and ITO/PET substrates were 89.2%, 65.0%, and 77.8%, respectively. Scanning electron microscopy(SEM) images of the film surfaces indicated that the grain was uniform. The cross-sectional SEM images showed that the ZnO films were columnar structures whose c-axis was perpendicular to the film surface. The test results for a fabricated ZnO thin film based energy harvester showed that its output voltage increased with increasing acceleration of external vibration.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA23080000,XDB31000000,XDA19050000)National Natural Science Foundation of China(31821001,31872248,32070450,32171487,32001097)+2 种基金Ministry of Ecology and Environment of China(2019HB2096001006)Sichuan Science and Technology Program(2021JDRC0024)。
文摘DEAR EDITOR, Despite the vulnerability of primates to the negative impacts of human activities and climate change, there is still room for optimism. Notably, years of conservation efforts may have paid off for the golden snub-nosed monkey(Rhinopithecus roxellana). Our field surveys confirmed the existence of 188 to 220 wild multilevel societies(MLS) of R. roxellana, with an estimated 22 710 to 26 130 individuals in 2019。
文摘We consider a bistable mesoscopic chemical reaction system and calculate entropy produc- tion along the dominant pathway during nonequilibrium phase transition. Using probability generating function method and eikonal approximation, we first convert the chemical master equation into the classical Hamilton-Jacobi equation, and then find the dominant pathways between two steady states in the phase space by calculating zero-energy trajectories. We find that entropy productions are related to the actions of the forward and backward dominant pathways. At the coexistence point where the stabilities of the two steady states are equiv alent, both the system entropy change and the medium entropy change are zero; whereas at non-coexistence point both of them are nonzero.
基金supported by the China National Postdoctoral Program for Innovative Talents(BX20220384)the National Natural Science Foundation of China(52175301)。
文摘Solid-state lithium batteries(SSLBs)solve safety issues and are potentially energy-dense alternatives to next-generation energy storage systems.Battery green recycling routes are responsible for the widespread use of SSLBs due to minimizing environmental contamination,reducing production costs,and providing a sustainable solution for resources,e.g.,saving rare earth elements(La,Ta,etc.).Herein,a solid-state recycling strategy is proposed to achieve green recycling of the crucial component solidstate electrolytes(SSEs)in spent SSLBs.The short-circuited garnet Li_(6.5)La_(3)Zr_(1.5)Ta_(0.5)O_(12)(LLZTO)is broken into fine particles and mixed with fresh particles to improve sintering activity and achieve high packing density.The continuous Li absorption process promotes sufficient grain fusion and guarantees the transformation from tetragonal phase to pure cubic phase for high-performance recycled LLZTO.The Li-ion conductivity reaches 5.80×10^(-4)S cm-1with a relative density of 95.9%.Symmetric Li cell with asrecycled LLZTO shows long-term cycling stability for 700 h at 0.3 mA cm^(-2)without any voltage hysteresis.Full cell exhibits an excellent cycling performance with a discharge capacity of 141.5 mA h g^(-1)and a capacity retention of 92.1%after 400 cycles(0.2C).This work develops an environmentally friendly and economically controllable strategy to recycle SSE from spent SSLBs,guiding future directions of SSLBs large-scale industrial application and green recycling study.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB31020302)National Natural Science Foundation of China (32170507, 31730104,31870396, and 32070450)。
文摘DEAR EDITOR,Movement patterns can reflect species-specific characteristics of individuals and animal groups at a given scale. Accurate three-dimensional(3D) assessment can quantify the relationship between movement patterns of an animal and its unique habitat. Here, we evaluated the effects of habitat structure on movement patterns of the golden snub-nosed monkey(Rhinopithecus roxellana). We used airborne light detection and ranging(LiDAR) to map the 3D structure of the temperate forest in the Qinling Mountains(Shaanxi, China).
基金supported by the National Natural Science Foundation of China(22205147).
文摘The rational design of green chemical,low-cost,and highly efficient solid-state electrolytes for Li-metal anode is a promising but still challenging strategy for preventing Li dendrite growth and developing safe and ultralong cycle life Li-metal batteries.Herein,a homogeneous composite solid polymer electrolyte(CSPE)is fabricated with water as the ideal dispersion medium,hectorite(Ht)as nanofiller,and poly(ethylene oxide)(PEO)as the matrix,to guide uniform Li plating/stripping.Benefiting from the merit of Ht can form uniformly dispersed nanosheets in water,the obtained CSPE inheres to a low melting point,robust mechanical property,and high Li^(+)transference number.Moreover,the fabricated Li symmetric battery using PEO-Ht-LiClO_(4)CSPE keeps cycling steadily for 4000 h.The well demonstrated water-based CSPE paves the way for developing low-cost,environmentally friendly,and safe solid-state electrolytes for Li-metal batteries.
基金financially supported by the University Natural Science Research Project of Anhui Province(No.2022AH050848)the Graduate Innovation Fund of Anhui Province(No.2022xscx082)the National Natural Science Foundation of China(No.12304134)。
文摘To solve the problem of high photogenerated carrier recombination rate and low photoelectric conversion efficiency of TiO_(2)-based materials,a simple N-doped anatase/rutile TiO_(2) heterophase nanorod film was designed by a low-temperature hydrothermal method in this work.The enhanced separation and transport of photogenerated charges were facilitated by the smaller contact barrier and appropriate band matching between anatase TiO_(2)nanoparticles and rutile TiO_(2) nanorods.The introduction of N doping in anatase TiO_(2) resulted in an upward shift of the valence band and a narrowing of the band gap,consequently enhancing the efficiency of visible light utilization.The combination of the heterophase junction and N-doping exhibited a synergistic effect,effectively suppressing the recombination of photogenerated charges and enhancing the photoelectric conversion efficiency of the photoanode.Under AM 1.5G irradiation,the photocurrent density(J)of the A-TO(N)@R-TONR photoanode reached2.19 mA·cm^(-2)(V_(RHE,1.23 eV)).Additionally,the incident photon-electron conversion efficiency(IPCE)and the charge injection efficiency(η)reached 81.4%and 51.6%at320 nm.Furthermore,the J,IPCE,andηvalues of the A-TO(N)@R-TONR photoanode were 2.96,2.1 and 3.2times those of pure R-TONR photoanode,respectively.This work presents a rational strategy for designing efficient TiO_(2)-based photoanodes.
基金financially supported by the National Key R&D Program of China (2021YFD1900700)the China Agricultural Research System (CARS-3-1-31)。
文摘The Yellow River Basin is an important food production area and an ecological challenge for China, where environmental protection and water scarcity are the major constraints. For the upper reaches of the Yellow River Basin,optimizing the adoption of chemicals in agricultural production and integrating crops with livestock are the key strategies for protecting the eco-environment.For dryland agriculture in the middle and upper reaches, this study summarizes four aspects of efficient precipitation techniques in terms of collection,storage, conservation, and use, which have greatly improved crop yields and supported dryland crop production. Irrigated agriculture in the middle and lower reaches is the core area of China's grain production, where the area under water-saving irrigation reached 13.0 Mha in 2018, greatly improving water use. Compared with 1998, cereal production in 2018 increased by 62.2 Mt under similar total water withdrawals(49.7 billion to 51.6 billion m~3),and the annual soil erosion at the Tongguan Hydrological Observatory reduced by 584 million m~3 in 2018, achieving great success in environmental protection and efficient water use. The Chinese government has set a goal for the Yellow River Basin to become the national leader in environmental protection and efficient water use by 2035. Such a high demand requires the combined efforts of the whole community, as well as the adoption of new technologies,coordinated basin-wide development, and adequate policy support.
基金Supported by A Grant from the National Natural Science Foundation of China,No. 30870746
文摘AIM:To investigate the role of endoplasmic reticulum(ER) stress in cancer radiotherapy and its molecular mechanism.METHODS:Tunicamycin(TM) was applied to induce ER stress in human esophageal cancer cell line EC109,and the radiosensitization effects were detected by acute cell death and clonogenic survival assay.Cell cycle arrest induced by TM was determined by flow cytometric analysis after the cellular DNA content was labeled with propidium iodide.Apoptosis of EC109 cells induced by TM was detected by annexin V staining and Western blotting of caspase-3 and its substrate poly ADP-ribose polymerase.Autophagic response was determined by acridine orange(AO) staining and Western blotting of microtubule-associated protein-1 light chain-3(LC3) and autophagy related gene 5(ATG5).In order to test the biological function of autophagy,specific inhibitor or Beclin-1 knockdown was used to inhibit autophagy,and its effect on cell apoptosis was thus detected.Additionally,involvement of the phosphatidylinositol-3 kinase(PI3K)/Akt/mammalian target of the rapamycin(mTOR) pathway was also detected by Western blotting.Finally,male nude mice inoculated subcutaneously with EC109 cells were used to confirm cell model observations.RESULTS:Our results showed that TM treatment enhanced cell death and reduced the colony survival fraction induced by ionizing radiation(IR),which suggested an obvious radiosensitization effect of TM.Moreover,TM and IR combination treatment led to a significant increase of G2/M phase and apoptotic cells,compared with IR alone.We also observed an increase of AO positive cells,and the protein level of LC3-II and ATG5 was induced by TM treatment,which suggested an autophagic response in EC109 cells.However,inhibition of autophagy by using a chemical inhibitor or Beclin-1 silencing led to increased cell apoptosis and decreased cell viability,which suggested a cytoprotective role of autophagy in stressed EC109 cells.Furthermore,TM treatment also activated mTORC1,and in turn reduced Akt phosphorylation,which suggested the PI3K/Akt/mTOR signal pathway was involved in the TM-induced autophagic response in EC109 cells.Tumor xenograft results also showed synergistic retarded tumor growth by TM treatment and IR,as well as the involvement of the PI3K/Akt/mTOR pathway.CONCLUSION:Our data showed that TM treatment sensitized human esophageal cancer cells to radiation via apoptosis and autophagy both in vitro and in vivo.
基金gratefully acknowledge the support for the work from Ministry of Science and Technology of China(2020YFA0908900)National Natural Science Foundation of China(21935011 and 21725403)+2 种基金Shenzhen Science and Technology Innovation Commission(KQTD20200820113012029 and JCYJ20220818100601003)Guangdong Basic and Applied Basic Research Foundation(2022A1515110321,2019A1515110511)Guangdong Provincial Key Laboratory of Advanced Biomaterials(2022B1212010003).
文摘Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal(GI)perforation management.However,several concerns remain for the existing bioadhesives including slow and/or weak adhesive,poor mechanical strength,low biocompatibility,and poor biodegradability,which largely limit their clinical application in GI perforation repair.In this work,we introduce an in situ injectable Tetra-PEG hydrogel bioadhesive(SS)composed of tetra-armed poly(ethylene glycol)amine(Tetra-PEG-NH2)and tetra-armed poly(ethylene glycol)succinimidyl succinate(Tetra-PEG-SS)for the sutureless repair of GI defects.The SS hydrogel exhibits rapid gelation behavior and high burst pressure and is capable of providing instant robust adhesion and fluid-tight sealing in the ex vivo porcine intestinal and gastric models.Importantly,the succinyl ester linkers in the SS hydrogel endow the bioadhesive with suitable in vivo degradability to match the new GI tissue formation.The in vivo evaluation in the rat GI injured model further demonstrates the successful sutureless sealing and repair of the intestine and stomach by the SS hydrogel with the advantages of neglectable postsurgical adhesion,suppressed inflammation,and enhanced angiogenesis.Together,our results support potential clinical applications of the SS bioadhesive for the high-efficient repair of GI perforation.
基金This work is financially supported by National Key R&D Program of China(2018YFA0704000 and 2020YFA0908800)Basic Research Program of Shenzhen(JCYJ20200109105620482 and JCYJ20180507182413022)Shenzhen Science and Technology Program(KQTD20190929172538530).
文摘Heptamethine cyanines(Cy7)are one of the most important dyes in bioimaging and phototherapy,but they often suffer from poor photostability or limited photothermal conversion efficiency.Here,a facile molecular engineering approach to regulating the photophysical properties of Cy7 by metal ions is demonstrated.By innovatively modifying the nitrogen with functional groups,a novel terpyridine-grafted nitrogen-terminated Cy7 scaffold(denoted as CydtPy)was synthesized and exhibited tunable photophysical properties when chelating with various metal ions(Mn^(2+),Fe^(2+),etc.).In comparison with metal-ion-free PEGylated CydtPy(LET-11),Mn^(2+)-chelated LET-11(namely,LET-11-Mn)exhibited the increased fluorescence emission intensity,and Fe^(2+)-chelated LET-11(namely,LET-11-Fe)showed the enhanced photostability with~2-fold increase in photothermal conversion efficiency.By simply switching the chelated metal ion species,LET-11-Mn or LET-11-Fe could be used for near-infrared fluorescence imaging,magnetic resonance imaging,or photoacoustic imaging.Furthermore,LET-11-Fe displayed superior synergistic efficacy of photothermal therapy and chemodynamic therapy both in vitro and in vivo.This work not only provides a new strategy for regulating the photophysical properties of cyanine dyes but also establishes a versatile nanoplatform for cancer theranostics.
基金financially supported by the National Natural Science Foundation of China(No.11774001)Anhui Project(No.Z010118169)Open Fund Project of Zhejiang Engineering Research Center of MEMS in Shaoxing University(No.MEMSZJERC2202)。
文摘Graphene quantum dots(GQDs)doped InGaO(IGO)thin film transistors(TFTs)have been fabricated based on solution-driven ZrO_(x) as gate dielectrics.Compare to pure IGO TFTs,superior electrical performance of the GQDs-IGO TFTs can be achieved by adjusting the doping concentration.It has been demonstrated that GQDs-modified IGO TFTs devices with GQDs doping content of0.3 mg·ml^(-1)have the optimized performances,including field-effect mobility(μ_(FE))of 22.02 cm^(2)·V^(-1)·s^(-1),on/off current ratio(I_(on)/I_(off))of 7.06×10^(7),subthreshold swing(SS)of 0.09 V·dec^(-1),hysteresis of 0.04 V and interfacial trap states(D_(it))of 1.03×10^(12)cm^(-2).In addition,bias stress and illumination stress tests have been performed and excellent stability has been achieved for optimized GQDs-IGO-TFTs.The GQDs-IGO TFTs device showed smaller threshold voltage shift of 0.12 and 0.04 V under positive bias stress(PBS)test and negative bias stress(NBS)test for 3600 s,respectively.And it showed smaller threshold voltage shift of 0.27 and 0.34 V for red light under the PBS and NBS test for 3600 s,respectively.Meanwhile,it showed smaller threshold voltage shift of0.20 and 0.22 V for green light under PBS and NBS test for3600 s,respectively.It also showed smaller threshold voltage shift of 0.17 and 0.12 V for blue under the positive bias illumination stress(PBIS)test and negative bias illumination stress(NBIS)test for 3600 s,respectively.Lowfrequency noise(LFN)characteristics of GQDs-IGO/ZrO_(x)TFTs indicated that the noise source came from the fluctuations in mobility.Finally,a low voltage resistor-loaded unipolar inverter has been built based on GQDs-IGO/ZrO_(x)TFT,demonstrating good dynamic response behavior and a maximum gain of 7.4.These experimental results have suggested that solution-processed GQDs-IGO/ZrO_(x)TFT may envision potential applications in low-cost and large-area electronics.
基金supported by the Natural Science Foundation of China(Nos.22175138,21875180)the Key Research and Development Program of Shaanxi(No.2021GXLH-Z023)the Independent Innovation Capability Improvement Project of Xi’an Jiaotong University(No.PY3A066)。
文摘Developing efficient photosensitizers for C-P bond construction is highly important and remains a challenge due to the urgently needed for the synthesis of modified nucleosides,nucleotides,and other phosphine-containing ligands.Herein,two pyrene-tethered bismoviologen derivatives(Py-BiV^(2+))were designed and synthesized for visible-light-induced C-P bonds formation.The photochemical and electrochemical properties of Py-BiV^(2+)were studied systemically,certifying fine-tunable opto-electronic properties through the number of pyrene groups(4,n=1;6,n=2).The prepared Py-BiV^(2+)showed strong light absorption,while retaining good redox features and chromic response features that were inherent to viologens.4 exhibited accelerated photoinduced electron transfer in the presence of the electron donor(pyrene)and the generated 4(radical cation)showed higher stability.Accordingly,Py-BiV^(2+)directly served as photosensitizers for the first time in the visible-light-induced C(sp^(3))-P and C(sp^(2))-P bonds formation.As expected,these novel viologen derivatives exhibited good catalytic performance and good substrate expansibility under ambient conditions.