The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stres...The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stress in creep or constant strain in relaxation is not usually attained in natural geological systems.Therefore,generalized relaxation tests that explore the simultaneous changes of stress and strain with time under different stress levels with constant pore-water pressure are conducted in this study.The results show that in area Ⅰ,area Ⅱ,and area Ⅲ,the stress and strain both change synchronously with time and show similar evolutionary laws as the strain-time curve for creep or the stress-time curve for relaxation.When the applied stress level surpasses the δ_(ci) or δ_(cd) threshold,the variations in stress and strain and their respective rates of change exhibit a significant increase.The radial deformation and its rate of change exhibit greater sensitivity in response to stress levels.The apparent strain deforms homogeneously at the primary stage,and subsequently,gradually localizes due to the microcrack development at the secondary stage.Ultimately,interconnection of the microcracks causes the formation of a shear-localization zone at the tertiary stage.The strain-time responses inside and outside the localization zone are characterized by local strain accumulation and inelastic unloading during the secondary and tertiary stages,respectively.The width of the shear-localization zone is found to range from 4.43 mm to 7.08 mm and increased with a longer time-to-failure.Scanning electron microscopy(SEM)reveals a dominant coalescence of intergranular cracks on the fracture surface,and the degree of physiochemical deterioration caused by water-rock interaction is more severe under a longer lifetime.The brittle sandstone’s time-dependent deformation is essentially controlled by microcrack development during generalized relaxation,and its expectancy-life is determined by its initial microstructural state and the rheological path.展开更多
Li-air batteries have attracted extensive attention because of their ultrahigh theoretical energy density. However, the potential safety hazard of flammable organic liquid electrolytes hinders their practical applicat...Li-air batteries have attracted extensive attention because of their ultrahigh theoretical energy density. However, the potential safety hazard of flammable organic liquid electrolytes hinders their practical applications. Replacing liquid electrolytes with solidstate electrolytes(SSEs) is expected to fundamentally overcome the safety issues. In this work, we focus on the development and challenge of solid-state Li-air batteries(SSLABs). The rise of different types of SSEs, interfacial compatibility and verifiability in SSLABs are presented. The corresponding strategies and prospects of SSLABs are also proposed. In particular, combining machine learning method with experiment and in situ(or operando)techniques is imperative to accelerate the development of SSLABs.展开更多
Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and a...Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and advancements in brain organoids,few studies have comprehensively summarized and analyzed the global trends in this area of neuroscience.To identify and further facilitate the development of cerebral organoids,we utilized bibliometrics and visualization methods to analyze the global trends and evolution of brain organoids in the last 10 years.First,annual publications,countries/regions,organizations,journals,authors,co-citations,and keywords relating to brain organoids were identified.The hotspots in this field were also systematically identified.Subsequently,current applications for brain organoids in neuroscience,including human neural development,neural disorders,infectious diseases,regenerative medicine,drug discovery,and toxicity assessment studies,are comprehensively discussed.Towards that end,several considerations regarding the current challenges in brain organoid research and future strategies to advance neuroscience will be presented to further promote their application in neurological research.展开更多
This paper presents a finite element framework for imposing frictional contact conditions on embedded fracture faces,implemented by the constant-strain assumed enhanced strain(AES)method,where penalty method is used t...This paper presents a finite element framework for imposing frictional contact conditions on embedded fracture faces,implemented by the constant-strain assumed enhanced strain(AES)method,where penalty method is used to impose both non-penetration constraint and Coulomb’s law of friction.The proposed constant-strain AES method for modeling embedded frictional contact can be cast into an integration algorithm similar to those used in the classical plasticity theory,where displacement jump is calculated from the local traction equilibrium at Gauss point,so the method does not introduce any additional global degrees of freedom.Moreover,constant-strain elements are often desirable in practice because they can be easily created automatically for large-scale engineering applications with complicated geometries.As encountered in other enriched finite element methods for frictional contact,the problem of normal contact pressure oscillations is also observed in the constant-strain AES method.Therefore,we developed a strain-smoothing procedure to effectively mitigate the oscillations.We investigated and verified the proposed AES framework through several numerical examples,and illustrated the capability of this method in solving challenging nonlinear frictional contact problems.展开更多
Photothermal(PTT) and photodynamic(PDT) combined therapy has been hindered to clinical translation, due to the lack of available biomaterials, difficult designs of functions,and complex chemical synthetic or preparati...Photothermal(PTT) and photodynamic(PDT) combined therapy has been hindered to clinical translation, due to the lack of available biomaterials, difficult designs of functions,and complex chemical synthetic or preparation procedures. To actualize a high-efficiency combination therapy for cancer via a feasible approach, three readily available materials are simply associated together in one-pot, namely the single-walled carbon nanohorns(SWCNH), zinc phthalocyanine(ZnPc), and surfactant TPGS. The established nanodispersion is recorded as PCT. The association of SWCNH/ZnPc/TPGS was confirmed by energy dispersive spectrum, Raman spectrum and thermogravimetric analysis. Under lighting, PCT induced a temperature rising up to about 60 ℃ due to the presence of SWCNH, production a 7-folds of singlet oxygen level elevation because of ZnPc, which destroyed almost all4T1 tumor cells in vitro. The photothermal effect of PCT depended on both laser intensity and nanodispersion concentration in a linear and nonlinear manner, respectively. After a single peritumoral injection in mice and laser treatment, PCT exhibited the highest tumor temperature rise(to 65 ℃) among all test groups, completely destroyed primary tumor without obvious toxicity, and inhibited distant site tumor. Generally, this study demonstrated the high potential of PCT nanodispersion in tumor combined therapy.展开更多
Dear Editor, Histone methylation is a dynamic process that plays important roles in gene transcription regulation, and a number of enzymes have been shown to catalyze the removal of methyl marks [1]. Shi et al. （200...Dear Editor, Histone methylation is a dynamic process that plays important roles in gene transcription regulation, and a number of enzymes have been shown to catalyze the removal of methyl marks [1]. Shi et al. （2004） identified one of the amino oxidases, lysine-specific demethylase 1 （LSD1）, as the first specific demethylase for both mono（me） and dimethylation （me2） of H3K4 and H3K9 in humans [2].展开更多
Conventional chemotherapy based on cytotoxic drugs is facing tough challenges recently following the advances of monoclonal antibodies and molecularly targeted drugs.It is critical to inspire new potential to remodel ...Conventional chemotherapy based on cytotoxic drugs is facing tough challenges recently following the advances of monoclonal antibodies and molecularly targeted drugs.It is critical to inspire new potential to remodel the value of this classical therapeutic strategy.Here,we fabricate bisphosphonate coordination lipid nanogranules(BC-LNPs)and load paclitaxel(PTX)to boost the chemo-and immuno-therapeutic synergism of cytotoxic drugs.Alendronate in BC-LNPs@PTX,a bisphosphonate to block mevalonate metabolism,works as both the structure and drug constituent in nanogranules,where alendronate coordinated with calcium ions to form the particle core.The synergy of alendronate enhances the efficacy of paclitaxel,suppresses tumor metastasis,and alters the cytotoxic mechanism.Differing from the paclitaxel-induced apoptosis,the involvement of alendronate inhibits the mevalonate metabolism,changes the mitochondrial morphology,disturbs the redox homeostasis,and causes theaccumulation of mitochondrial ROS and lethal lipid peroxides(LPO).These factors finally trigger the ferroptosis of tumor cells,an immunogenic cell death mode,which remodels the suppressive tumor immune microenvironment and synergizes with immunotherapy.Therefore,by switching paclitaxel-induced apoptosis to mevalonate metabolism-triggered ferroptosis,BC-LNPs@PTX provides new insight into the development of cytotoxic drugs and highlights the potential of metabolism regulation in cancer therapy.展开更多
Mycorrhiza helper bacteria(MHB)can promote the formation and functioning of arbuscular mycorrhizal(AM)symbiosis,but their role and application potential in coping with soil-borne diseases are still unclear.A 14-week g...Mycorrhiza helper bacteria(MHB)can promote the formation and functioning of arbuscular mycorrhizal(AM)symbiosis,but their role and application potential in coping with soil-borne diseases are still unclear.A 14-week greenhouse pot experiment was conducted to obtain several actinomycete strains helping AM symbiosis in suppressing the Phytophthora blight of pepper(Capsicum annuum L.),using a soil inoculated with Phytophthora capsici after sterilization.Five Streptomyces strains,including S.pseudogriseolus,S.albogriseolus,S.griseoaurantiacus,S.tricolor,and S.tendae,as well as the AM fungus(Funneliformis caledonium)were tested.The Phytophthora blight severity reached 66%at full productive stage in the uninoculated control,and inoculation of F.caledonium,S.griseoaurantiacus,and S.tricolor alone significantly decreased(P<0.05)it to 47%,40%,and 35%,respectively.Compared to F.caledonium alone,additional inoculation of S.tricolor or S.tendae,which were isolated from the rhizosphere of a healthy individual in an infected field,significantly elevated(P<0.05)root mycorrhizal colonization,root biomass,fruit yield,and total K acquisitions of pepper and further significantly decreased(P<0.05)blight severity.According to the feature of enhancing disease-suppression by AM symbiosis,both S.tricolor and S.tendae were confirmed as MHB strains here.Specifically,S.tendae had a stronger performance in directly accelerating mycorrhization,while S.tricolor was also an antagonist to the pathogenic P.capsici.Furthermore,S.griseoaurantiacus with the independent disease-suppression function was not an MHB strain here.The redundancy analyses demonstrated that when AM fungus was present,root mycorrhizal colonization replaced soil pH becoming the main factor affecting pepper Phytophthora blight.Thus,S.tricolor and S.tendae seemed to have the value of preparation and application in the future to help AM symbiosis against pepper Phytophthora blight.展开更多
To explore the impact of ursodeoxycholic acid(UDCA)on severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection and clinical outcomes in patients with autoimmune liver disease(AILD).Patients diagnosed with ...To explore the impact of ursodeoxycholic acid(UDCA)on severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection and clinical outcomes in patients with autoimmune liver disease(AILD).Patients diagnosed with AILD were enrolled and divided into a UDCA group and a non-UDCA group based on whether they received UDCA treatment.Relevant data were collected regarding AILD diagnosis,treatment,biochemical indicators,and imaging examination.The incidence of SARS-CoV-2 infection and the prognosis of AILD patients were observed.A total of 1,138 patients completed follow-up.The usage rate of hormone(P=0.003)and immunosuppressant(P=0.001)used for treating AILD in the non-UDCA group was markedly lower than in the UDCA group.The UDCA usage rate was markedly lower in SARS-CoV-2 infected patients than in uninfected patients(P=0.003).The rate of SARS-CoV-2 infection in the non-UDCA group was significantly higher than in the UDCA group(P=0.018).Logistic regression analysis showed that UDCA use(P=0.003)was correlated to a lower incidence of SARS-CoV-2,while immunosuppressant use(P=0.017)increased the incidence.Recovery time from SARS-CoV-2 infection was markedly longer for those receiving UDCA treatment than those in the non-UDCA group(P=0.018).UDCA is associated with low SARS-CoV-2 incidence in AILD patients,while immunosuppressant increases its incidence instead.Patients receiving UDCA treatment have a longer recovery time after being infected.展开更多
Aprotic lithium-oxygen(Li-O_(2))batteries have a high theoretical energy density,but they face challenges such as cathode blockage,high charge overpotential,and poor cycling stability.These are caused by sluggish reac...Aprotic lithium-oxygen(Li-O_(2))batteries have a high theoretical energy density,but they face challenges such as cathode blockage,high charge overpotential,and poor cycling stability.These are caused by sluggish reaction kinetics and severe parasitic reactions.Enhancing the performance of Li-O_(2) batteries necessitates the development of efficient catalysts.These catalysts not only augment both the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)but also inhibit undesirable parasitic reactions.In this work,we demonstrated for the first time a multifunctional soluble catalyst of iridium(III)acetylacetonate(Ir(acac)_(3))that could speed up oxygen electrochemistry.Ir(acac)_(3) regulated the ORR pathway and the reactivity of superoxide radical species by forming a reversible intermediate complex(Ir(acac)_(3)-O_(2)^(−)).During charging,Ir(acac)_(3) acted as a redox mediator and aided in Li_(2)O_(2) decomposition by reacting with superoxide intermediates.Moreover,as demonstrated by operando UV-visible spectroscopy,the lower charge potential significantly reduced the generation of highly reactive singlet oxygen(^(1)O_(2))intermediates.As a result,the Ir(acac)_(3)-mediated Li-O_(2) battery showed low overpotential,large capacity,and stable cyclability.This study offers a new approach to achieving efficient Li-O_(2) batteries and provides an opportunity to suppress parasitic reactions.展开更多
We demonstrate single-mode microdisk lasers in the telecom band with ultralow thresholds on erbium-ytterbium co-doped thin-film lithium niobate(TFLN).The active microdisk was fabricated with high-Q factors by photolit...We demonstrate single-mode microdisk lasers in the telecom band with ultralow thresholds on erbium-ytterbium co-doped thin-film lithium niobate(TFLN).The active microdisk was fabricated with high-Q factors by photolithography-assisted chemomechanical etching.Thanks to the erbium-ytterbium co-doping providing high optical gain,the ultralow loss nanostructuring,and the excitation of high-Q coherent polygon modes,which suppresses multimode lasing and allows high spatial mode overlap between pump and lasing modes,single-mode laser emission operating at 1530 nm wavelength was observed with an ultralow threshold,under a 980-nm-band optical pump.The threshold was measured as low as 1μW,which is one order of magnitude smaller than the best results previously reported in single-mode active TFLN microlasers.The conversion efficiency reaches 4.06×10^(-3),which is also the highest value reported in single-mode active TFLN microlasers.展开更多
It has become an inevitable trend of human development to seek resources from the deep underground.However,rock encountered in deep underground engineering is usually in an anisotropic stress state(σ_(1)>σ>σ_...It has become an inevitable trend of human development to seek resources from the deep underground.However,rock encountered in deep underground engineering is usually in an anisotropic stress state(σ_(1)>σ>σ_(3))due to the influences of geological structures and engineering disturbances.It is therefore essential to study the mechanical,seepage,and dynamic disaster behaviors of deep rock under true triaxial stress to ensure the safe operation of deep rock engineering and the efficient exploitation of deep resources.In recent years,experimental techniques and research on true triaxial rock mechanics have achieved fruitful results that have promoted the rapid development of deep rock mechanics;thus,it is necessary to systematically review and summarize these developments.This work first introduced several typical true triaxial testing apparatus and then reviewed the corresponding research progress on rock deformation,strength,failure mode,brittleness,and energy as well as the 3D volumetric fracturing(dynamic disaster)properties of deep rocks under true triaxial stress.Then,several commonly used true triaxial rock strength criteria and their applicability,the permeability characteristics and mathematical models of deep reservoir rocks,and the disaster-causing processes and mechanisms of disturbed volumetric fracturing(rockburst,compound dynamic disasters)in deep rock engineering were described.This work may provide an essential reference for addressing the true triaxial rock mechanics issues involved in deep rock engineering,especially regarding the stability of surrounding rock at depth,disaster prevention and control,and oil and gas exploitation.展开更多
The canopy of subtropical natural forests usually consists of several co-dominant populations(CDPs),which play a crucial role in forest structure,formation of the forest environment,and ecological function.However,lit...The canopy of subtropical natural forests usually consists of several co-dominant populations(CDPs),which play a crucial role in forest structure,formation of the forest environment,and ecological function.However,little attention has been given to changes in spatial patterns in CDPs during natural succession.Cyclobalanopsis glauca(Thunb.)Oerst.,Quercus variabilis Blume,and Pinus yunnanensis var.tenuifolia W.C.Cheng & Y.W.Law are canopy species that form CDPs in zonal forests along the Nanpan River in southwest China.We used the g(r) function and its bivariate distribution model,g_(12)(r),which is based on distances between pairs of points,to explore the dynamics of the three CDP species with respect to distribution patterns and spatial correlations in two secondary forests(one 30-year-old forest [30-YF] and one 57-year-old forest [57-YF]).The following key results were obtained:(1) there was a clumped pattern in the 30-YF,but the intensity of aggregation varied among populations and life stages.The distribution pattern gradually shifted to become random with longer succes sion time(i.e.,30-YF vs.57-YF),expansion of the observation scale(r=0-20 m),and at later life stages.(2) Aside from the mid-sized C.glauca trees and large P.yunnanensis trees,the trees repulsed each other at certain scales(r=0-2,5-6,11-12,14-16 m) in the 30-YF.Almost all of the life stages in the CDPs were independently correlated.This independent correlation was exacerbated by a longer succession time.(3) An increase in life stages and longer succession also promoted independent changes in intraspecific correlations.(4) Intraspecific correlations were stronger than interspecific correlations.Our results showed that reducing exclusive competition is essential to coexistence in CDPs.Inter-and intra-specific repulsion may occur at the same time,but intraspecific repulsion was the main driving force behind the random distributions and independent correlations.展开更多
Currently,the cancer immunotherapy has made great progress while antitumor vaccine attracts substantial attention.Still,the selection of adjuvants as well as antigens are always the most crucial issues for better vacc...Currently,the cancer immunotherapy has made great progress while antitumor vaccine attracts substantial attention.Still,the selection of adjuvants as well as antigens are always the most crucial issues for better vaccination.In this study,we proposed a biomimetic antitumor nanovaccine based on biocompatible nanocarriers and tumor cell membrane antigens.Briefly,endogenous calcium pyrophosphate nanogranules with possible immune potentiating effect are designed and engineered,both as delivery vehicles and adjuvants.Then,these nanocarriers are coated with lipids and B16-OVA tumor cell membranes,so the biomembrane proteins can serve as tumor-specific antigens.It was found that calcium pyrophosphate nanogranules themselves were compatible and possessed adjuvant effect,while membrane proteins including tumor associated antigen were transferred onto the nanocarriers.It was demonstrated that such a biomimetic nanovaccine could be well endocytosed by dendritic cells,promote their maturation and antigen-presentation,facilitate lymph retention,and trigger obvious immune response.It was confirmed that the biomimetic vaccine could induce strong T-cell response,exhibit excellent tumor therapy and prophylactic effects,and simultaneously possess nice biocompatibility.In general,the present investigation might provide insights for the further design and application of antitumor vaccines.展开更多
Deep rock mass tends to be broken into blocks when mining for materials deep below the surface.The rock layer of the roof of the mine can be regarded as a system of blocks of fractured rock mass.When subjected to high...Deep rock mass tends to be broken into blocks when mining for materials deep below the surface.The rock layer of the roof of the mine can be regarded as a system of blocks of fractured rock mass.When subjected to high ground stress and mining-induced disturbance,the efect of the ultra-low friction of the block system easily becomes apparent,and can induce rock burst and other accidents.By taking the block of rock mass as research object,this study developed a test system for ultra-low friction to experimentally examine its efects on the broken blocks under stress wave-induced disturbance.We used the horizontal displacement of the working block as the characteristic parameter refecting the efect of ultra-low friction,and examine its characteristic laws of horizontal displacement,acceleration,and energy when subjected to the efects of ultra-low friction by changing the frequency and amplitude of the stress wave-induced disturbance.The results show that the frequency of stress wave-induced disturbance is related to the generation of ultra-low friction in the broken block.The frequency of disturbance of the stress wave is within 1–3 Hz,and signifcantly increases the maximum acceleration and horizontal displacement of the broken blocks.The greater the intensity of the stress wave-induced disturbance is,the higher is the degree of block fragmentation,and the more likely are efects of ultra-low friction to occur between the blocks.The greater the intensity of the horizontal impact load is,the higher is the degree of fragmentation of the rock mass,and the easier it is for the efects of ultra-low friction to occur.Stress wave-induced disturbance and horizontal impact are the main causes of sliding instability of the broken blocks.When the dominant frequency of the kinetic energy of the broken block is within 20 Hz,the efects of ultra-low friction are more likely.展开更多
In this paper, Fe-doped TiO_2 photocatalyst supported on hollow glass microbeads(Fe-TiO_2 /beads)is prepared by dip-coating method, which uses hollow glass microbeads as the carriers and tetrabutylorthotitanate [Ti(O...In this paper, Fe-doped TiO_2 photocatalyst supported on hollow glass microbeads(Fe-TiO_2 /beads)is prepared by dip-coating method, which uses hollow glass microbeads as the carriers and tetrabutylorthotitanate [Ti(OC_4H_9)_4] as the raw material. The phase structure, ingredient, morphologies, particle size and shell thickness of the products are characterized by X-ray powder diffraction(XRD), energy-dispersive spectroscopy(EDS) and field emission scanning electron microscope(FESEM). The feasibility of photocatylic degradation of Rhodamine B(Rh B) under illumination of UV-vis light is studied. The results show that the core-shell structure catalyst is composed of Fe-doped anatase TiO_2 and hollow glass microbeads, and the catalytic activity of the TiO_2 is markedly enhanced by Fe ion doping. The optimum concentration of Fe ion is 0.1%(molecular fraction) in the precursor and the photocatalytic activity can be increased to 98% compared with that of the undoped one. The presence of ferrum elements neither influences the transformation of anatase to rutile, nor creates new crystal phases. The possible mechanism of photocatalytic oxidation is also discussed.展开更多
联邦学习(federated learning,FL)是一种以保护客户隐私数据为中心的分布式处理网络,为解决隐私泄露问题提供了前景良好的解决方案.然而,FL的一个主要困境是高度非独立同分布(non-independent and identically distributed,non-IID)的...联邦学习(federated learning,FL)是一种以保护客户隐私数据为中心的分布式处理网络,为解决隐私泄露问题提供了前景良好的解决方案.然而,FL的一个主要困境是高度非独立同分布(non-independent and identically distributed,non-IID)的数据会导致全局模型性能很差.尽管相关研究已经探讨了这个问题,但本文发现当面对non-IID数据、不稳定的客户端参与以及深度模型时,现有方案和标准基线FedAvg相比,只有微弱的优势或甚至更差,因此严重阻碍了FL的隐私保护应用价值.为解决这个问题,本文提出了一种对non-IID数据鲁棒的优化方案:FedUp.该方案在保留FL隐私保护特点的前提下,进一步提升了全局模型的泛化鲁棒性.FedUp的核心思路是最小化全局经验损失函数的上限来保证模型具有低的泛化误差.大量仿真实验表明,FedUp显著优于现有方案,并对高度non-IID数据以及不稳定和大规模客户端的参与具有鲁棒性.展开更多
The accurate determination of the carbon-neutrality capacity(CNC)of a region is crucial for developing policies related to emissions and climate change.However,a systematic diagnostic method for determining the CNC th...The accurate determination of the carbon-neutrality capacity(CNC)of a region is crucial for developing policies related to emissions and climate change.However,a systematic diagnostic method for determining the CNC that considers the rock chemical weathering carbon sink(RCS)is lacking.Moreover,it is challenging but indispensable to establish a fast and practical index model to determine the CNC.Here,we selected Guizhou as the study area,used the methods for different types of carbon sinks,and constructed a CNC index(CNCI)model.We found that:(1)the carbonate rock chemical weathering carbon sink flux was 30.3 t CO_(2)km^(-2)yr^(-1).Guizhou accounted for 1.8%of the land area and contributed 5.4%of the carbonate chemical weathering carbon sink;(2)the silicate rock chemical weathering carbon sink and its flux were 1.44×10^(3)t CO_(2)and 2.43 t CO_(2)km^(-2)yr^(-1),respectively;(3)the vegetation-soil ecosystem carbon sink and its flux were 1.37×10^(8)t CO_(2)and 831.70 t CO_(2)km^(-2)yr^(-1),respectively;(4)the carbon emissions(CEs)were 280 Tg CO_(2),about 2.8%of the total for China;and(5)the total carbon sinks in Guizhou were 160 Tg CO_(2),with a CNCI of 57%,which is 4.8 times of China and 2.1 times of the world.In summary,we conducted a systematic diagnosis of the CNC considering the RCS and established a CNCI model.The results of this study have a strong implication and significance for national and global CNC determination and gap analysis.展开更多
A variety of techniques have been used for treating avascular necrosis of the femoral head(ANFH),but have frequently failed.In this study,we proposed aβ-TCP system for the treatment of ANFH by boosting revascularizat...A variety of techniques have been used for treating avascular necrosis of the femoral head(ANFH),but have frequently failed.In this study,we proposed aβ-TCP system for the treatment of ANFH by boosting revascularization and bone regeneration.The angio-conductive properties and concurrent osteogenesis of the highly interconnected porousβ-TCP scaffold were revealed and quantified through an in vivo model that simulated the ischemic environment of ANFH.Mechanical test and finite element analysis showed that the mechanical loss caused by tissue necrosis and surgery was immediately partially compensated after implantation,and the strength of the operated femoral head was adaptively increased and eventually returned to normal bone,along with continuous material degradation and bone regeneration.For translational application,we further conducted a multi-center open-label clinical trial to assess the efficacy of theβ-TCP system in treating ANFH.Two hundred fourteen patients with 246 hips were enrolled for evaluation,and 82.1%of the operated hips survived at a 42.79-month median follow-up.The imaging results,hip function,and pain scores were dramatically improved compared to preoperative levels.ARCO stage II disease outperformed stage III in terms of clinical effectiveness.Thus,bio-adaptive reconstruction using theβ-TCP system is a promising hip-preserving strategy for the treatment of ANFH.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52304099,52172625)Shenzhen Science and Technology Program(Grant No.RCYX20221008092903013).
文摘The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stress in creep or constant strain in relaxation is not usually attained in natural geological systems.Therefore,generalized relaxation tests that explore the simultaneous changes of stress and strain with time under different stress levels with constant pore-water pressure are conducted in this study.The results show that in area Ⅰ,area Ⅱ,and area Ⅲ,the stress and strain both change synchronously with time and show similar evolutionary laws as the strain-time curve for creep or the stress-time curve for relaxation.When the applied stress level surpasses the δ_(ci) or δ_(cd) threshold,the variations in stress and strain and their respective rates of change exhibit a significant increase.The radial deformation and its rate of change exhibit greater sensitivity in response to stress levels.The apparent strain deforms homogeneously at the primary stage,and subsequently,gradually localizes due to the microcrack development at the secondary stage.Ultimately,interconnection of the microcracks causes the formation of a shear-localization zone at the tertiary stage.The strain-time responses inside and outside the localization zone are characterized by local strain accumulation and inelastic unloading during the secondary and tertiary stages,respectively.The width of the shear-localization zone is found to range from 4.43 mm to 7.08 mm and increased with a longer time-to-failure.Scanning electron microscopy(SEM)reveals a dominant coalescence of intergranular cracks on the fracture surface,and the degree of physiochemical deterioration caused by water-rock interaction is more severe under a longer lifetime.The brittle sandstone’s time-dependent deformation is essentially controlled by microcrack development during generalized relaxation,and its expectancy-life is determined by its initial microstructural state and the rheological path.
基金supported by National Key Research and Development Program of China (No.2021YFF0500600)NSFC (22279120)Key R&D projects in Henan Province (221111240100)。
文摘Li-air batteries have attracted extensive attention because of their ultrahigh theoretical energy density. However, the potential safety hazard of flammable organic liquid electrolytes hinders their practical applications. Replacing liquid electrolytes with solidstate electrolytes(SSEs) is expected to fundamentally overcome the safety issues. In this work, we focus on the development and challenge of solid-state Li-air batteries(SSLABs). The rise of different types of SSEs, interfacial compatibility and verifiability in SSLABs are presented. The corresponding strategies and prospects of SSLABs are also proposed. In particular, combining machine learning method with experiment and in situ(or operando)techniques is imperative to accelerate the development of SSLABs.
基金supported by the National Natural Science Foundation of China,Nos.82204083(to ML)and 12372303(to BW)the Natural Science Foundation of Chongqing,No.cstc2021jcy-jmsxmX0171(to ML).
文摘Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and advancements in brain organoids,few studies have comprehensively summarized and analyzed the global trends in this area of neuroscience.To identify and further facilitate the development of cerebral organoids,we utilized bibliometrics and visualization methods to analyze the global trends and evolution of brain organoids in the last 10 years.First,annual publications,countries/regions,organizations,journals,authors,co-citations,and keywords relating to brain organoids were identified.The hotspots in this field were also systematically identified.Subsequently,current applications for brain organoids in neuroscience,including human neural development,neural disorders,infectious diseases,regenerative medicine,drug discovery,and toxicity assessment studies,are comprehensively discussed.Towards that end,several considerations regarding the current challenges in brain organoid research and future strategies to advance neuroscience will be presented to further promote their application in neurological research.
基金supported by the Fundamental Research Funds for the Central Universities (Grant No.2021FZZX001-14)and ZJU-ZCCC Institute of Collaborative Innovation (Grant No.ZDJG2021005).
文摘This paper presents a finite element framework for imposing frictional contact conditions on embedded fracture faces,implemented by the constant-strain assumed enhanced strain(AES)method,where penalty method is used to impose both non-penetration constraint and Coulomb’s law of friction.The proposed constant-strain AES method for modeling embedded frictional contact can be cast into an integration algorithm similar to those used in the classical plasticity theory,where displacement jump is calculated from the local traction equilibrium at Gauss point,so the method does not introduce any additional global degrees of freedom.Moreover,constant-strain elements are often desirable in practice because they can be easily created automatically for large-scale engineering applications with complicated geometries.As encountered in other enriched finite element methods for frictional contact,the problem of normal contact pressure oscillations is also observed in the constant-strain AES method.Therefore,we developed a strain-smoothing procedure to effectively mitigate the oscillations.We investigated and verified the proposed AES framework through several numerical examples,and illustrated the capability of this method in solving challenging nonlinear frictional contact problems.
基金supported by the National Natural Science Foundation of China (81690264)the National Basic Research Program of China (2015CB932100)the Innovation Team of the Ministry of Education (BMU20110263)。
文摘Photothermal(PTT) and photodynamic(PDT) combined therapy has been hindered to clinical translation, due to the lack of available biomaterials, difficult designs of functions,and complex chemical synthetic or preparation procedures. To actualize a high-efficiency combination therapy for cancer via a feasible approach, three readily available materials are simply associated together in one-pot, namely the single-walled carbon nanohorns(SWCNH), zinc phthalocyanine(ZnPc), and surfactant TPGS. The established nanodispersion is recorded as PCT. The association of SWCNH/ZnPc/TPGS was confirmed by energy dispersive spectrum, Raman spectrum and thermogravimetric analysis. Under lighting, PCT induced a temperature rising up to about 60 ℃ due to the presence of SWCNH, production a 7-folds of singlet oxygen level elevation because of ZnPc, which destroyed almost all4T1 tumor cells in vitro. The photothermal effect of PCT depended on both laser intensity and nanodispersion concentration in a linear and nonlinear manner, respectively. After a single peritumoral injection in mice and laser treatment, PCT exhibited the highest tumor temperature rise(to 65 ℃) among all test groups, completely destroyed primary tumor without obvious toxicity, and inhibited distant site tumor. Generally, this study demonstrated the high potential of PCT nanodispersion in tumor combined therapy.
文摘Dear Editor, Histone methylation is a dynamic process that plays important roles in gene transcription regulation, and a number of enzymes have been shown to catalyze the removal of methyl marks [1]. Shi et al. （2004） identified one of the amino oxidases, lysine-specific demethylase 1 （LSD1）, as the first specific demethylase for both mono（me） and dimethylation （me2） of H3K4 and H3K9 in humans [2].
基金supported by National Key Research and Development Program (2022YFA1206100, China)Natural Science Foundation of Beijing Municipality (L212013, China)+1 种基金AI+Health Collaborative Innovation Cultivation Project (Z211100003521002,China)National Natural Science Foundation of China(82073786, 81872809, U20A20412, 81821004)
文摘Conventional chemotherapy based on cytotoxic drugs is facing tough challenges recently following the advances of monoclonal antibodies and molecularly targeted drugs.It is critical to inspire new potential to remodel the value of this classical therapeutic strategy.Here,we fabricate bisphosphonate coordination lipid nanogranules(BC-LNPs)and load paclitaxel(PTX)to boost the chemo-and immuno-therapeutic synergism of cytotoxic drugs.Alendronate in BC-LNPs@PTX,a bisphosphonate to block mevalonate metabolism,works as both the structure and drug constituent in nanogranules,where alendronate coordinated with calcium ions to form the particle core.The synergy of alendronate enhances the efficacy of paclitaxel,suppresses tumor metastasis,and alters the cytotoxic mechanism.Differing from the paclitaxel-induced apoptosis,the involvement of alendronate inhibits the mevalonate metabolism,changes the mitochondrial morphology,disturbs the redox homeostasis,and causes theaccumulation of mitochondrial ROS and lethal lipid peroxides(LPO).These factors finally trigger the ferroptosis of tumor cells,an immunogenic cell death mode,which remodels the suppressive tumor immune microenvironment and synergizes with immunotherapy.Therefore,by switching paclitaxel-induced apoptosis to mevalonate metabolism-triggered ferroptosis,BC-LNPs@PTX provides new insight into the development of cytotoxic drugs and highlights the potential of metabolism regulation in cancer therapy.
基金funded by the National Natural Science Foundation of China(No.42177304)the National Key R&D Program of China(No.2022YFD1500202)supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2016285)。
文摘Mycorrhiza helper bacteria(MHB)can promote the formation and functioning of arbuscular mycorrhizal(AM)symbiosis,but their role and application potential in coping with soil-borne diseases are still unclear.A 14-week greenhouse pot experiment was conducted to obtain several actinomycete strains helping AM symbiosis in suppressing the Phytophthora blight of pepper(Capsicum annuum L.),using a soil inoculated with Phytophthora capsici after sterilization.Five Streptomyces strains,including S.pseudogriseolus,S.albogriseolus,S.griseoaurantiacus,S.tricolor,and S.tendae,as well as the AM fungus(Funneliformis caledonium)were tested.The Phytophthora blight severity reached 66%at full productive stage in the uninoculated control,and inoculation of F.caledonium,S.griseoaurantiacus,and S.tricolor alone significantly decreased(P<0.05)it to 47%,40%,and 35%,respectively.Compared to F.caledonium alone,additional inoculation of S.tricolor or S.tendae,which were isolated from the rhizosphere of a healthy individual in an infected field,significantly elevated(P<0.05)root mycorrhizal colonization,root biomass,fruit yield,and total K acquisitions of pepper and further significantly decreased(P<0.05)blight severity.According to the feature of enhancing disease-suppression by AM symbiosis,both S.tricolor and S.tendae were confirmed as MHB strains here.Specifically,S.tendae had a stronger performance in directly accelerating mycorrhization,while S.tricolor was also an antagonist to the pathogenic P.capsici.Furthermore,S.griseoaurantiacus with the independent disease-suppression function was not an MHB strain here.The redundancy analyses demonstrated that when AM fungus was present,root mycorrhizal colonization replaced soil pH becoming the main factor affecting pepper Phytophthora blight.Thus,S.tricolor and S.tendae seemed to have the value of preparation and application in the future to help AM symbiosis against pepper Phytophthora blight.
基金the National Key Research and Development Program(2022YFC2603500,2022YFC2603505)Beijing Municipal Health Commission high-level public health technical personnel construction project,discipline leader-03-26,Beijing Hospitals Authority Clinical medicine Development of special funding support(XMLX 202127)+1 种基金the capital health research and development of special public health project(2022-1-2172)The Digestive Medical Coordinated Development Center of Beijing Hospitals Authority(XXZ0302).
文摘To explore the impact of ursodeoxycholic acid(UDCA)on severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection and clinical outcomes in patients with autoimmune liver disease(AILD).Patients diagnosed with AILD were enrolled and divided into a UDCA group and a non-UDCA group based on whether they received UDCA treatment.Relevant data were collected regarding AILD diagnosis,treatment,biochemical indicators,and imaging examination.The incidence of SARS-CoV-2 infection and the prognosis of AILD patients were observed.A total of 1,138 patients completed follow-up.The usage rate of hormone(P=0.003)and immunosuppressant(P=0.001)used for treating AILD in the non-UDCA group was markedly lower than in the UDCA group.The UDCA usage rate was markedly lower in SARS-CoV-2 infected patients than in uninfected patients(P=0.003).The rate of SARS-CoV-2 infection in the non-UDCA group was significantly higher than in the UDCA group(P=0.018).Logistic regression analysis showed that UDCA use(P=0.003)was correlated to a lower incidence of SARS-CoV-2,while immunosuppressant use(P=0.017)increased the incidence.Recovery time from SARS-CoV-2 infection was markedly longer for those receiving UDCA treatment than those in the non-UDCA group(P=0.018).UDCA is associated with low SARS-CoV-2 incidence in AILD patients,while immunosuppressant increases its incidence instead.Patients receiving UDCA treatment have a longer recovery time after being infected.
基金supported by the National Natural Science Foundation of China (NSFCgrant no.22202182).
文摘Aprotic lithium-oxygen(Li-O_(2))batteries have a high theoretical energy density,but they face challenges such as cathode blockage,high charge overpotential,and poor cycling stability.These are caused by sluggish reaction kinetics and severe parasitic reactions.Enhancing the performance of Li-O_(2) batteries necessitates the development of efficient catalysts.These catalysts not only augment both the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)but also inhibit undesirable parasitic reactions.In this work,we demonstrated for the first time a multifunctional soluble catalyst of iridium(III)acetylacetonate(Ir(acac)_(3))that could speed up oxygen electrochemistry.Ir(acac)_(3) regulated the ORR pathway and the reactivity of superoxide radical species by forming a reversible intermediate complex(Ir(acac)_(3)-O_(2)^(−)).During charging,Ir(acac)_(3) acted as a redox mediator and aided in Li_(2)O_(2) decomposition by reacting with superoxide intermediates.Moreover,as demonstrated by operando UV-visible spectroscopy,the lower charge potential significantly reduced the generation of highly reactive singlet oxygen(^(1)O_(2))intermediates.As a result,the Ir(acac)_(3)-mediated Li-O_(2) battery showed low overpotential,large capacity,and stable cyclability.This study offers a new approach to achieving efficient Li-O_(2) batteries and provides an opportunity to suppress parasitic reactions.
基金supported by the National Key R&D Program of China(Nos.2019YFA0705000,2022YFA1404600,and 2022YFA1205100)the National Natural Science Foundation of China(NSFC)(Nos.62122079,12192251,62235019,12334014,12134001,12104159,and 11933005)+4 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0301403)the Shanghai Municipal Science and Technology Major Project(No.2019SHZDZX01)the Science and Technology Commission of Shanghai Municipality(Nos.21DZ1101500 and 23ZR1481800)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2020249)the Engineering Research Center for Nanophotonics&Advanced Instrument,Ministry of Education,East China Normal University(No.2023nmc005)。
文摘We demonstrate single-mode microdisk lasers in the telecom band with ultralow thresholds on erbium-ytterbium co-doped thin-film lithium niobate(TFLN).The active microdisk was fabricated with high-Q factors by photolithography-assisted chemomechanical etching.Thanks to the erbium-ytterbium co-doping providing high optical gain,the ultralow loss nanostructuring,and the excitation of high-Q coherent polygon modes,which suppresses multimode lasing and allows high spatial mode overlap between pump and lasing modes,single-mode laser emission operating at 1530 nm wavelength was observed with an ultralow threshold,under a 980-nm-band optical pump.The threshold was measured as low as 1μW,which is one order of magnitude smaller than the best results previously reported in single-mode active TFLN microlasers.The conversion efficiency reaches 4.06×10^(-3),which is also the highest value reported in single-mode active TFLN microlasers.
基金This research was supported by the National Natural Science Foundation of China(No.52104209)the Postdoctoral Research Foundation of China(No.2021M692192)+1 种基金the National Natural Science Foundation of China(Nos.51827901 and 52174082)the Program for Guangdong Introducing Innovative and Entrepre-neurial Teams(No.2019ZT08G315).
文摘It has become an inevitable trend of human development to seek resources from the deep underground.However,rock encountered in deep underground engineering is usually in an anisotropic stress state(σ_(1)>σ>σ_(3))due to the influences of geological structures and engineering disturbances.It is therefore essential to study the mechanical,seepage,and dynamic disaster behaviors of deep rock under true triaxial stress to ensure the safe operation of deep rock engineering and the efficient exploitation of deep resources.In recent years,experimental techniques and research on true triaxial rock mechanics have achieved fruitful results that have promoted the rapid development of deep rock mechanics;thus,it is necessary to systematically review and summarize these developments.This work first introduced several typical true triaxial testing apparatus and then reviewed the corresponding research progress on rock deformation,strength,failure mode,brittleness,and energy as well as the 3D volumetric fracturing(dynamic disaster)properties of deep rocks under true triaxial stress.Then,several commonly used true triaxial rock strength criteria and their applicability,the permeability characteristics and mathematical models of deep reservoir rocks,and the disaster-causing processes and mechanisms of disturbed volumetric fracturing(rockburst,compound dynamic disasters)in deep rock engineering were described.This work may provide an essential reference for addressing the true triaxial rock mechanics issues involved in deep rock engineering,especially regarding the stability of surrounding rock at depth,disaster prevention and control,and oil and gas exploitation.
基金financially supported by the National Key Research and Development Program of China(Grant No.2016YFC0502101-04)the Guangxi Key Research and Development Program (Grant No.Guike AB163 80254)+1 种基金the National Science Foundation of China (Grant No.31400542)Guangxi Special Fund Project for Innovation-driven Development (Grant No.AA 17204087-8)。
文摘The canopy of subtropical natural forests usually consists of several co-dominant populations(CDPs),which play a crucial role in forest structure,formation of the forest environment,and ecological function.However,little attention has been given to changes in spatial patterns in CDPs during natural succession.Cyclobalanopsis glauca(Thunb.)Oerst.,Quercus variabilis Blume,and Pinus yunnanensis var.tenuifolia W.C.Cheng & Y.W.Law are canopy species that form CDPs in zonal forests along the Nanpan River in southwest China.We used the g(r) function and its bivariate distribution model,g_(12)(r),which is based on distances between pairs of points,to explore the dynamics of the three CDP species with respect to distribution patterns and spatial correlations in two secondary forests(one 30-year-old forest [30-YF] and one 57-year-old forest [57-YF]).The following key results were obtained:(1) there was a clumped pattern in the 30-YF,but the intensity of aggregation varied among populations and life stages.The distribution pattern gradually shifted to become random with longer succes sion time(i.e.,30-YF vs.57-YF),expansion of the observation scale(r=0-20 m),and at later life stages.(2) Aside from the mid-sized C.glauca trees and large P.yunnanensis trees,the trees repulsed each other at certain scales(r=0-2,5-6,11-12,14-16 m) in the 30-YF.Almost all of the life stages in the CDPs were independently correlated.This independent correlation was exacerbated by a longer succession time.(3) An increase in life stages and longer succession also promoted independent changes in intraspecific correlations.(4) Intraspecific correlations were stronger than interspecific correlations.Our results showed that reducing exclusive competition is essential to coexistence in CDPs.Inter-and intra-specific repulsion may occur at the same time,but intraspecific repulsion was the main driving force behind the random distributions and independent correlations.
基金supported by the National Key R&D Program of China(2017YFA0205600)the National Natural Science Foundation of China(81690264,81821004).
文摘Currently,the cancer immunotherapy has made great progress while antitumor vaccine attracts substantial attention.Still,the selection of adjuvants as well as antigens are always the most crucial issues for better vaccination.In this study,we proposed a biomimetic antitumor nanovaccine based on biocompatible nanocarriers and tumor cell membrane antigens.Briefly,endogenous calcium pyrophosphate nanogranules with possible immune potentiating effect are designed and engineered,both as delivery vehicles and adjuvants.Then,these nanocarriers are coated with lipids and B16-OVA tumor cell membranes,so the biomembrane proteins can serve as tumor-specific antigens.It was found that calcium pyrophosphate nanogranules themselves were compatible and possessed adjuvant effect,while membrane proteins including tumor associated antigen were transferred onto the nanocarriers.It was demonstrated that such a biomimetic nanovaccine could be well endocytosed by dendritic cells,promote their maturation and antigen-presentation,facilitate lymph retention,and trigger obvious immune response.It was confirmed that the biomimetic vaccine could induce strong T-cell response,exhibit excellent tumor therapy and prophylactic effects,and simultaneously possess nice biocompatibility.In general,the present investigation might provide insights for the further design and application of antitumor vaccines.
基金supported by the National Science Foundation of China(51974148)the Liaoning Xingliao Talent Program(XLYC1807130).
文摘Deep rock mass tends to be broken into blocks when mining for materials deep below the surface.The rock layer of the roof of the mine can be regarded as a system of blocks of fractured rock mass.When subjected to high ground stress and mining-induced disturbance,the efect of the ultra-low friction of the block system easily becomes apparent,and can induce rock burst and other accidents.By taking the block of rock mass as research object,this study developed a test system for ultra-low friction to experimentally examine its efects on the broken blocks under stress wave-induced disturbance.We used the horizontal displacement of the working block as the characteristic parameter refecting the efect of ultra-low friction,and examine its characteristic laws of horizontal displacement,acceleration,and energy when subjected to the efects of ultra-low friction by changing the frequency and amplitude of the stress wave-induced disturbance.The results show that the frequency of stress wave-induced disturbance is related to the generation of ultra-low friction in the broken block.The frequency of disturbance of the stress wave is within 1–3 Hz,and signifcantly increases the maximum acceleration and horizontal displacement of the broken blocks.The greater the intensity of the stress wave-induced disturbance is,the higher is the degree of block fragmentation,and the more likely are efects of ultra-low friction to occur between the blocks.The greater the intensity of the horizontal impact load is,the higher is the degree of fragmentation of the rock mass,and the easier it is for the efects of ultra-low friction to occur.Stress wave-induced disturbance and horizontal impact are the main causes of sliding instability of the broken blocks.When the dominant frequency of the kinetic energy of the broken block is within 20 Hz,the efects of ultra-low friction are more likely.
文摘In this paper, Fe-doped TiO_2 photocatalyst supported on hollow glass microbeads(Fe-TiO_2 /beads)is prepared by dip-coating method, which uses hollow glass microbeads as the carriers and tetrabutylorthotitanate [Ti(OC_4H_9)_4] as the raw material. The phase structure, ingredient, morphologies, particle size and shell thickness of the products are characterized by X-ray powder diffraction(XRD), energy-dispersive spectroscopy(EDS) and field emission scanning electron microscope(FESEM). The feasibility of photocatylic degradation of Rhodamine B(Rh B) under illumination of UV-vis light is studied. The results show that the core-shell structure catalyst is composed of Fe-doped anatase TiO_2 and hollow glass microbeads, and the catalytic activity of the TiO_2 is markedly enhanced by Fe ion doping. The optimum concentration of Fe ion is 0.1%(molecular fraction) in the precursor and the photocatalytic activity can be increased to 98% compared with that of the undoped one. The presence of ferrum elements neither influences the transformation of anatase to rutile, nor creates new crystal phases. The possible mechanism of photocatalytic oxidation is also discussed.
文摘联邦学习(federated learning,FL)是一种以保护客户隐私数据为中心的分布式处理网络,为解决隐私泄露问题提供了前景良好的解决方案.然而,FL的一个主要困境是高度非独立同分布(non-independent and identically distributed,non-IID)的数据会导致全局模型性能很差.尽管相关研究已经探讨了这个问题,但本文发现当面对non-IID数据、不稳定的客户端参与以及深度模型时,现有方案和标准基线FedAvg相比,只有微弱的优势或甚至更差,因此严重阻碍了FL的隐私保护应用价值.为解决这个问题,本文提出了一种对non-IID数据鲁棒的优化方案:FedUp.该方案在保留FL隐私保护特点的前提下,进一步提升了全局模型的泛化鲁棒性.FedUp的核心思路是最小化全局经验损失函数的上限来保证模型具有低的泛化误差.大量仿真实验表明,FedUp显著优于现有方案,并对高度non-IID数据以及不稳定和大规模客户端的参与具有鲁棒性.
基金supported jointly by Joint Funds of the National Natural Science Foundation of China(NO.U22A20619)Western Light Cross-team Program of Chinese Academy of Sciences(No.xbzg-zdsys-202101)+6 种基金National Natural Science Foundation of China(No.42077455&No.42167032)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB40000000&No.XDA23060100)Guizhou Provincial Science and Technology Projects(No.2022-198)High-level innovative talents in Guizhou Province(No.GCC[2022]015-1&No.2016e5648)Guizhou Provincial 2020 Science and Technology Subsidies(No.GZ2020SIG)Opening Fund of the State Key Laboratory of Environmental Geochemistry(No.SKLEG2022206&No.SKLEG2022208)The central government leading local science and technology development(No.QianKeZhongYinDi[2021]4028).
文摘The accurate determination of the carbon-neutrality capacity(CNC)of a region is crucial for developing policies related to emissions and climate change.However,a systematic diagnostic method for determining the CNC that considers the rock chemical weathering carbon sink(RCS)is lacking.Moreover,it is challenging but indispensable to establish a fast and practical index model to determine the CNC.Here,we selected Guizhou as the study area,used the methods for different types of carbon sinks,and constructed a CNC index(CNCI)model.We found that:(1)the carbonate rock chemical weathering carbon sink flux was 30.3 t CO_(2)km^(-2)yr^(-1).Guizhou accounted for 1.8%of the land area and contributed 5.4%of the carbonate chemical weathering carbon sink;(2)the silicate rock chemical weathering carbon sink and its flux were 1.44×10^(3)t CO_(2)and 2.43 t CO_(2)km^(-2)yr^(-1),respectively;(3)the vegetation-soil ecosystem carbon sink and its flux were 1.37×10^(8)t CO_(2)and 831.70 t CO_(2)km^(-2)yr^(-1),respectively;(4)the carbon emissions(CEs)were 280 Tg CO_(2),about 2.8%of the total for China;and(5)the total carbon sinks in Guizhou were 160 Tg CO_(2),with a CNCI of 57%,which is 4.8 times of China and 2.1 times of the world.In summary,we conducted a systematic diagnosis of the CNC considering the RCS and established a CNCI model.The results of this study have a strong implication and significance for national and global CNC determination and gap analysis.
文摘A variety of techniques have been used for treating avascular necrosis of the femoral head(ANFH),but have frequently failed.In this study,we proposed aβ-TCP system for the treatment of ANFH by boosting revascularization and bone regeneration.The angio-conductive properties and concurrent osteogenesis of the highly interconnected porousβ-TCP scaffold were revealed and quantified through an in vivo model that simulated the ischemic environment of ANFH.Mechanical test and finite element analysis showed that the mechanical loss caused by tissue necrosis and surgery was immediately partially compensated after implantation,and the strength of the operated femoral head was adaptively increased and eventually returned to normal bone,along with continuous material degradation and bone regeneration.For translational application,we further conducted a multi-center open-label clinical trial to assess the efficacy of theβ-TCP system in treating ANFH.Two hundred fourteen patients with 246 hips were enrolled for evaluation,and 82.1%of the operated hips survived at a 42.79-month median follow-up.The imaging results,hip function,and pain scores were dramatically improved compared to preoperative levels.ARCO stage II disease outperformed stage III in terms of clinical effectiveness.Thus,bio-adaptive reconstruction using theβ-TCP system is a promising hip-preserving strategy for the treatment of ANFH.
