We previously combined reduced graphene oxide(rGO)with gelatin-methacryloyl(GelMA)and polycaprolactone(PCL)to create an rGO-GelMA-PCL nerve conduit and found that the conductivity and biocompatibility were improved.Ho...We previously combined reduced graphene oxide(rGO)with gelatin-methacryloyl(GelMA)and polycaprolactone(PCL)to create an rGO-GelMA-PCL nerve conduit and found that the conductivity and biocompatibility were improved.However,the rGO-GelMA-PCL nerve conduits differed greatly from autologous nerve transplants in their ability to promote the regeneration of injured peripheral nerves and axonal sprouting.Extracellular vesicles derived from bone marrow mesenchymal stem cells(BMSCs)can be loaded into rGO-GelMA-PCL nerve conduits for repair of rat sciatic nerve injury because they can promote angiogenesis at the injured site.In this study,12 weeks after surgery,sciatic nerve function was measured by electrophysiology and sciatic nerve function index,and myelin sheath and axon regeneration were observed by electron microscopy,immunohistochemistry,and immunofluorescence.The regeneration of microvessel was observed by immunofluorescence.Our results showed that rGO-GelMA-PCL nerve conduits loaded with BMSC-derived extracellular vesicles were superior to rGO-GelMA-PCL conduits alone in their ability to increase the number of newly formed vessels and axonal sprouts at the injury site as well as the recovery of neurological function.These findings indicate that rGO-GelMA-PCL nerve conduits loaded with BMSC-derived extracellular vesicles can promote peripheral nerve regeneration and neurological function recovery,and provide a new direction for the curation of peripheral nerve defect in the clinic.展开更多
Objective This study was aimed to investigate the toxic effects of 3 nanomaterials, i.e. multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO), and reduced graphene oxide (RGO), on zebrafish embryos. Metho...Objective This study was aimed to investigate the toxic effects of 3 nanomaterials, i.e. multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO), and reduced graphene oxide (RGO), on zebrafish embryos. Methods The 2-h post-fertilization (hpf) zebrafish embryos were exposed to MWCNTs, GO, and RGO at different concentrations (1, 5, 10, 50, 100 mg/L) for 96 h. Afterwards, the effects of the 3 nanomateria on spontaneous movement, heart rate, hatching rate, length of larvae, mortality, and malformations Is were evaluated. Results Statistical analysis indicated that RGO significantly inhibited the hatching of zebrafish embryos. Furthermore, RGO and MWCNTs decreased the length of the hatched larvae at 96 hpf. No obvious morphological malformation or mortality was observed in the zebrafish embryos after exposure to the three nanomaterials. Conclusion MWCNTs, GO, and RGO were all toxic to zebrafish embryos to influence embryos hatching and larvae length. Although no obvious morphological malformation and mortality were observed in exposed zebrafish embryos, further studies on the toxicity of the three nanomaterials are still needed.展开更多
OBJECTIVE To assess whether N-acetylcysteine(NAC)and reduced glutathione(GSH)are effective in reversing flupirtine-induced hepatotoxicity and whether they have other beneficial effects when combined with flupirtine.ME...OBJECTIVE To assess whether N-acetylcysteine(NAC)and reduced glutathione(GSH)are effective in reversing flupirtine-induced hepatotoxicity and whether they have other beneficial effects when combined with flupirtine.METHODS The analgesic effects of NAC and flupirtine were first evaluated in carrageenaninduced inflammatory pain and paclitaxel-induced neuropathic pain.The combination subthreshold⁃ing approach was then used to determine whether the combination of NAC and flupirtine produced synergistic analgesic effects.Hepatotoxicity markers and histopathological examination of the liver were used to assess the efficacy of NAC and GSH in reversing flupirtine-induced hepato⁃toxicity.Finally,the effect of GSH on the safe range of flupirtine was assessed in an acute tox⁃icity assay.RESULTS Flupirtine and NAC pro⁃duced dose-dependent antiallodynic effects evoked by carrageenan and paclitaxel in mice.In the above model,the combination of NAC and flupirtine produced an unexpected synergistic analgesic effect.There were no significant differ⁃ences observed in the hepatotoxicity markers and liver histopathology between the experimen⁃tal group and the control group under NAC and GSH treatment.Finally,GSH(200 mg·kg^(-1))expanded the therapeutic index of flupirtine by 1.77 times.CONCLUSION NAC and GSH are effective in preventing liver damage caused by long-term flupirtine use,which provides a solu⁃tion for the safe and effective treatment of chronic pain with flupirtine.In addition,the other benefi⁃cial effects of NAC and GSH when combined with flupirtine may provide the basis for the devel⁃opment of a new therapy with minimal sideeffects and good efficacy.展开更多
Objective:To observe the clinical efficacy of dapagliflozin in the treatment of type 2 diabetes mellitus(T2DM)complicated with heart failure with mildly reduced ejection fraction(HFmrEF,40%≤LVEF<50%).Methods:A tot...Objective:To observe the clinical efficacy of dapagliflozin in the treatment of type 2 diabetes mellitus(T2DM)complicated with heart failure with mildly reduced ejection fraction(HFmrEF,40%≤LVEF<50%).Methods:A total of 84 patients with T2DM complicated with HFmrEF hospitalized in our hospital from October 2019 to October 2021 were selected,and random number table method was used to divide into the control group and the study group each 42 cases.Both groups used basal hypoglycemic and standardized anti-heart failure therapy,and the study group was treated with dapagliflozin simultaneously.Nine months later,the following indexes were compared between the two groups before and after treatment:the cardiac function indicators:N-terminal pro brain natriuretic peptide(NT-proBNP),left ventricular ejection fraction(LVEF);exercise endurance:6-minute walk distance(6MWD),NYHA cardiac function class,the score of the Minnesota living with heart failure questionnaire(MLHFQ)and the incidence of major adverse cardiovascular events(MACE).Results:Nine months later,the two groups showed decreased NT-proBNP level,increased LVEF,prolonged 6MWD,improved NYHA cardiac function grade,decreased MLHFQ score,and statistically significant differences within both groups compared with before treatment(P<0.05),after treatment significant differences were displayed between the two groups(P<0.05).Less patients had MACE events and adverse drug reactions in the study group compared with the control group.Conclusion:Dapagliflozin in the treatment of T2DM patients with HFmrEF can improve cardiac function indicators,improve exercise endurance,improve NYHA cardiac function class,improve patient's quality of life,and reduce the incidence of MACE events,with no obvious side effects.展开更多
This work presents a comprehensive fourth-order predictive modeling (PM) methodology that uses the MaxEnt principle to incorporate fourth-order moments (means, covariances, skewness, kurtosis) of model parameters, com...This work presents a comprehensive fourth-order predictive modeling (PM) methodology that uses the MaxEnt principle to incorporate fourth-order moments (means, covariances, skewness, kurtosis) of model parameters, computed and measured model responses, as well as fourth (and higher) order sensitivities of computed model responses to model parameters. This new methodology is designated by the acronym 4<sup>th</sup>-BERRU-PM, which stands for “fourth-order best-estimate results with reduced uncertainties.” The results predicted by the 4<sup>th</sup>-BERRU-PM incorporates, as particular cases, the results previously predicted by the second-order predictive modeling methodology 2<sup>nd</sup>-BERRU-PM, and vastly generalizes the results produced by extant data assimilation and data adjustment procedures.展开更多
This study investigated the effect of magnesium application on peanut growth and yield under two nitrogen(N)application rates in acidic soil in southern China.The chlorophyll content,net photosynthetic rate and dry ma...This study investigated the effect of magnesium application on peanut growth and yield under two nitrogen(N)application rates in acidic soil in southern China.The chlorophyll content,net photosynthetic rate and dry matter accumulation of the N-sensitive cultivar decreased under reduced N treatments,whereas no effect was observed on the relevant indicators in the N-insensitive variety GH1026.Mg application increased the net photosynthetic rate by increasing the expression of genes involved in chlorophyll synthesis and Rubisco activity in the leaves during the pegging stage under 50%N treatment,while no effect on the net photosynthetic rate was observed under the 100%N treatment.The rate of dry matter accumulation at the early growth stage,total dry matter accumulation and pod yield at harvest increased after Mg application under 50%N treatment by increasing the transportation of assimilates from stems and leaves to pods in both peanut varieties,whereas no effect was found under 100%N treatment.Moreover,Mg application increased the NUE under 50%N treatment.No improvement of NUE in either peanut variety was found under 100%N treatment,while Mg application under the 50%N treatment can obtain a higher economic benefit than the 100%N treatment.In acidic soil,application of 307.5 kg ha^(-1)of Mg sulfate fertilizer under 50%reduced nitrogen application is a suitable fertilizer management measure for improving carbon assimilation,NUE and achieve high peanut yields in southern China.展开更多
Soybean production systems that return plant residues to the soil surface are gaining in popularity. As these practices become more widespread, more crop and weed residues are being introduced into the upper soil prof...Soybean production systems that return plant residues to the soil surface are gaining in popularity. As these practices become more widespread, more crop and weed residues are being introduced into the upper soil profile. Greenhouse studies were conducted to determine the effects of varying concentrations of Palmer amaranth and pitted morningglory plant residues (aboveground portion of the plant) on soybean production. The study was arranged in a completely randomized experimental design with five treatments and five replications. Palmer amaranth and pitted morningglory residues were incorporated into soil at 20,000, 40,000, 80,000 and 160,000 ppm. Inert plastic residue at the same residue levels was included as a check. Soybean dry weight, leaf area and leaf tissue nutrient content were recorded during the study. A decrease in soybean dry weight and leaf area was observed as Palmer amaranth residue in the soil increased. Palmer amaranth residues of 160,000 ppm and 80,000 ppm in the soil significantly reduced soybean dry weight by 69% and 59%, respectively, and soybean leaf area by 60% and 57%, respectively. In contrast, pitted morningglory and inert plastic residues had no observable effect on soybean growth and development. This study demonstrated Palmer amaranth residues in the soil impacted early season soybean growth and development.展开更多
In this paper,we study reduced rings in which every element is a sum of three tripotents that commute,and determine the integral domains over which every n£n matrix is a sum of three tripotents.It is proved that ...In this paper,we study reduced rings in which every element is a sum of three tripotents that commute,and determine the integral domains over which every n£n matrix is a sum of three tripotents.It is proved that for an integral domain R,every matrix in M_(n)(R)is a sum of three tripotents if and only if R■Zp with p=2,3,5 or 7.展开更多
Three-dimensional(3D)porous absorbents have attracted significant attention in the oily wastewater treatment technology due to their high porosity and elasticity.Given their amphiphilic surface,they have a propensity ...Three-dimensional(3D)porous absorbents have attracted significant attention in the oily wastewater treatment technology due to their high porosity and elasticity.Given their amphiphilic surface,they have a propensity to simultaneously absorb water and oil,which restricts their range of applications.In this study,a reduced graphene oxide and titanium dioxide nanocomposite(rGO/TiO_(2))was used to fabricate an ultra-hydrophobic melamine sponge(MS)through interfacial modification using a solution immersion technique.To further modify it,poly-dimethylsiloxane(PDMS)was grafted onto its surface to establish stronger covalent bonds with the composite.The water contact angle of the sponge(rGO/TiO_(2)/PDMS/MS)was 164.2°,which satisfies the condition for ultrahydrophobicity.The evidence of its water repellency was demonstrated by the Cassie-Baxter theory and the lotus leaf effect.As a result of the increased density of rGO/TiO_(2)/PDMS/MS,it recorded an initial capacity that was 2 g/g lower than the raw MS for crude oil absorption.The raw MS retained 53% of its initial absorption capacity after 20 cycles of absorption,while rGO/TiO_(2)/PDMS/MS retained 97%,suggesting good recyclability.Excellent oil and organic solvent recovery(90%-96%)was demonstrated by rGO/TiO_(2)/PDMS/MS in oil-water combinations.In a continuous separation system,it achieved a remarkable separation efficiency of 2.4×10^(6)L/(m^(3)·h),and in turbulent emulsion separation,it achieved a demulsification efficiency of 90%-91%.This study provides a practical substitute for massive oil spill cleaning.展开更多
In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constrain...In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system complexity.Owing to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and yaw.In response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each step.To cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic angle.In order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control system.In order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step method.The feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition uncertainties.The results indicate that the designed controller can converge to the reference path and evidently decrease the distance between the impact point and target under different uncertainties.展开更多
The steel industry is considered an important basic sector of the national economy,and its high energy consumption and carbon emissions make it a major contributor to climate change,especially in China.The majority of...The steel industry is considered an important basic sector of the national economy,and its high energy consumption and carbon emissions make it a major contributor to climate change,especially in China.The majority of crude steel in China is produced via the energy-and carbon-intensive blast furnace–basic oxygen furnace(BF–BOF)route,which greatly relies on coking coal.In recent years,China’s steel sector has made significant progress in energy conservation and emission reduction,driven by decarbonization policies and regulations.However,due to the huge output of crude steel,the steel sector still produces 15%of the total national CO_(2) emissions.The direct reduced iron(DRI)plus scrap–electric arc furnace(EAF)process is currently considered a good alternative to the conventional route as a means of reducing CO_(2) emissions and the steel industry’s reliance on iron ore and coking coal,since the gas-based DRI plus scrap–EAF route is expected to be more promising than the coal-based one.Unfortunately,almost no DRI is produced in China,seriously restricting the development of the EAF route.Here,we highlight the challenges and pathways of the future development of DRI,with a focus on China.In the short term,replacing natural gas with coke oven gas(COG)and byproduct gas from the integrated refining and chemical sector is a more economically feasible and cleaner way to develop a gas-based route in China.As the energy revolution proceeds,using fossil fuels in combination with carbon capture,utilization,and storage(CCUS)and hydrogen will be a good alternative due to the relatively low cost.In the long term,DRI is expected to be produced using 100%hydrogen from renewable energy.Both the development of deep processing technologies and the invention of a novel binder are required to prepare high-quality pellets for direct reduction(DR),and further research on the one-step gas-based process is necessary.展开更多
Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface mo...Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface morphology and electric property was investigated.The results confirmed the dense membrane of PEDOT:PSS and the lamellar structure of PDDA-rGO on the fibers.It has excellent electrical conductivity and mechanical properties.The fiber based electrochemical transistor(FECTs)prepared by the composite conductive fiber has a maximum output current of 8.7 mA,a transconductance peak of 10 mS,an on time of 1.37 s,an off time of 1.6 s and excellent switching stability.Most importantly,the devices by layer by layer self-assembly technology opens a path for the true integration of organic electronics with traditional textile technologies and materials,laying the foundation for their later widespread application.展开更多
Due to the low water-cement ratio of ultra-high-performance concrete(UHPC),fluidity and shrinkage cracking are key aspects determining the performance and durability of this type of concrete.In this study,the effects ...Due to the low water-cement ratio of ultra-high-performance concrete(UHPC),fluidity and shrinkage cracking are key aspects determining the performance and durability of this type of concrete.In this study,the effects of different types of cementitious materials,chemical shrinkage-reducing agents(SRA)and steel fiber(SF)were assessed.Compared with M2-UHPC and M3-UHPC,M1-UHPC was found to have better fluidity and shrinkage cracking performance.Moreover,different SRA incorporation methods,dosage and different SF types and aspect ratios were implemented.The incorporation of SRA and SF led to a decrease in the fluidity of UHPC.SRA internal content of 1%(NSRA-1%),SRA external content of 1%(WSRA-1%),STS-0.22 and STE-0.7 decreased the fluidity of UHPC by 3.3%,8.3%,9.2%and 25%,respectively.However,SRA and SF improved the UHPC shrinkage cracking performance.NSRA-1%and STE-0.7 reduced the shrinkage value of UHPC by 40%and 60%,respectively,and increased the crack resistance by 338%and 175%,respectively.In addition,the addition of SF was observed to make the microstructure of UHPC more compact,and the compressive strength and flexural strength of 28 d were increased by 26.9%and 19.9%,respectively.展开更多
Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational...Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational domains,etc.Typical reduced order modeling techniques accelerate the solution of the parametric PDEs by projecting them onto a linear trial manifold constructed in the ofline stage.These methods often need a predefined mesh as well as a series of precomputed solution snapshots,and may struggle to balance between the efficiency and accuracy due to the limitation of the linear ansatz.Utilizing the nonlinear representation of neural networks(NNs),we propose the Meta-Auto-Decoder(MAD)to construct a nonlinear trial manifold,whose best possible performance is measured theoretically by the decoder width.Based on the meta-learning concept,the trial manifold can be learned in a mesh-free and unsupervised way during the pre-training stage.Fast adaptation to new(possibly heterogeneous)PDE parameters is enabled by searching on this trial manifold,and optionally fine-tuning the trial manifold at the same time.Extensive numerical experiments show that the MAD method exhibits a faster convergence speed without losing the accuracy than other deep learning-based methods.展开更多
Organic–inorganic hybrid perovskites are quite promising candidates in the field of electromagnetic wave (EMW) absorption due to their unique physicochemical properties. However, it is still a considerable challenge ...Organic–inorganic hybrid perovskites are quite promising candidates in the field of electromagnetic wave (EMW) absorption due to their unique physicochemical properties. However, it is still a considerable challenge to satisfy the light weight, broad bandwidth, and strong absorption properties simultaneously. Herein, the solution of methylammonium lead iodide (MAPbI3) perovskites was infiltrated into the pores of reduced graphene oxide (rGO) aerogels. After drying, a series of MAPbI3/rGO composite aerogel (MGA) materials were synthesized by anchoring the MAPbI3 perovskite nanoparticles to rGO sheets with the assistance of rGO templates. Through the adjustment of component ratios, excellent EMW absorption properties are obtained with the synergistic effects of polarization loss, conduction loss, and multiple reflection and scattering of MAPbI3 and rGO. The porous structure of the aerogel and the suitable group distribution ratio allowed the MGA-4 samples to obtain excellent impedance matching and ultra-low density of ∼ 7.69 mg·cm−3. At a low filling ratio of 15 wt.%, the MGA-4 sample simultaneously achieves highly efficient and broadband EMW absorption performance at a thin thickness. The MGA-4 sample obtained a minimum reflection loss value of −64.35 dB and the effective absorption bandwidth (EAB) value of 5.4 GHz at a thickness of 2.08 mm and a maximum EAB (EABmax) value of 6.2 GHz under 2.22 mm. The MGA-5 sample obtained a maximum EAB value of 6.4 GHz with the thinckness of 2.16 mm. Furthermore, the simulation results of the radar cross-section (RCS) verified the component-optimized composites are capable of achieving excellent EMW attenuation. This paper provides a new approach and valuable reference for the development of hybrid perovskite-based microwave absorption materials with lightweight, ultra-broadband, and strong absorption properties.展开更多
Considering the serious electromagnetic wave(EMW)pollution problems and complex application condition,there is a pressing need to amalgamate multiple functionalities within a single substance.However,the effective int...Considering the serious electromagnetic wave(EMW)pollution problems and complex application condition,there is a pressing need to amalgamate multiple functionalities within a single substance.However,the effective integration of diverse functions into designed EMW absorption materials still faces the huge challenges.Herein,reduced graphene oxide/carbon foams(RGO/CFs)with two-dimensional/three-dimensional(2D/3D)van der Waals(vdWs)heterostructures were meticulously engineered and synthesized utilizing an efficient methodology involving freeze-drying,immersing absorption,secondary freeze-drying,followed by carbonization treatment.Thanks to their excellent linkage effect of amplified dielectric loss and optimized impedance matching,the designed 2D/3D RGO/CFs vdWs heterostructures demonstrated commendable EMW absorption performances,achieving a broad absorption bandwidth of 6.2 GHz and a reflection loss of-50.58 dB with the low matching thicknesses.Furthermore,the obtained 2D/3D RGO/CFs vdWs heterostructures also displayed the significant radar stealth properties,good corrosion resistance performances as well as outstanding thermal insulation capabilities,displaying the great potential in complex and variable environments.Accordingly,this work not only demonstrated a straightforward method for fabricating 2D/3D vdWs heterostructures,but also outlined a powerful mixeddimensional assembly strategy for engineering multifunctional foams for electromagnetic protection,aerospace and other complex conditions.展开更多
The effects of sulfate reduced bacterium (SRB) on the corrosion behavior of 10CrMoAl steel in seawater were studied by chemical immersion, potentiodynamic polarization, electrochemical impedance spectroscopy measure...The effects of sulfate reduced bacterium (SRB) on the corrosion behavior of 10CrMoAl steel in seawater were studied by chemical immersion, potentiodynamic polarization, electrochemical impedance spectroscopy measurement, and scanning electron microscope techniques. The results show that the content of element sulfur in the corrosion product of 10CrMoAl steel in seawater with SRB is up to 9. 23 %, which is higher than that of the same in sterile seawater. X-ray diffraction demonstrates that the main corrosion product is FeS. SRB increases the corrosion rate by anodic depolarization of the metabolized sulfide product. SEM observation indicates that the corrosion product is not distributed continuously; in addition, bacilliform sulfate-reduced bacterium accumulates on the local surface of 10CrMoAl steel. Hence, SRB enhances sensitivity to the localized corrosion of 10CrMoAl steel in seawater.展开更多
The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion process.Compared with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinfor...The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion process.Compared with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal performance.By adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 alloy.The superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with matrix.The strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix composite.The RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.展开更多
基金supported by the National Natural Science Foundation of China, No. 31671248the Natural Science Foundation of Beijing, No. 7222198 (both to NH)
文摘We previously combined reduced graphene oxide(rGO)with gelatin-methacryloyl(GelMA)and polycaprolactone(PCL)to create an rGO-GelMA-PCL nerve conduit and found that the conductivity and biocompatibility were improved.However,the rGO-GelMA-PCL nerve conduits differed greatly from autologous nerve transplants in their ability to promote the regeneration of injured peripheral nerves and axonal sprouting.Extracellular vesicles derived from bone marrow mesenchymal stem cells(BMSCs)can be loaded into rGO-GelMA-PCL nerve conduits for repair of rat sciatic nerve injury because they can promote angiogenesis at the injured site.In this study,12 weeks after surgery,sciatic nerve function was measured by electrophysiology and sciatic nerve function index,and myelin sheath and axon regeneration were observed by electron microscopy,immunohistochemistry,and immunofluorescence.The regeneration of microvessel was observed by immunofluorescence.Our results showed that rGO-GelMA-PCL nerve conduits loaded with BMSC-derived extracellular vesicles were superior to rGO-GelMA-PCL conduits alone in their ability to increase the number of newly formed vessels and axonal sprouts at the injury site as well as the recovery of neurological function.These findings indicate that rGO-GelMA-PCL nerve conduits loaded with BMSC-derived extracellular vesicles can promote peripheral nerve regeneration and neurological function recovery,and provide a new direction for the curation of peripheral nerve defect in the clinic.
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education(200800191013)the Fundamental Research Funds for the Central Universities
文摘Objective This study was aimed to investigate the toxic effects of 3 nanomaterials, i.e. multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO), and reduced graphene oxide (RGO), on zebrafish embryos. Methods The 2-h post-fertilization (hpf) zebrafish embryos were exposed to MWCNTs, GO, and RGO at different concentrations (1, 5, 10, 50, 100 mg/L) for 96 h. Afterwards, the effects of the 3 nanomateria on spontaneous movement, heart rate, hatching rate, length of larvae, mortality, and malformations Is were evaluated. Results Statistical analysis indicated that RGO significantly inhibited the hatching of zebrafish embryos. Furthermore, RGO and MWCNTs decreased the length of the hatched larvae at 96 hpf. No obvious morphological malformation or mortality was observed in the zebrafish embryos after exposure to the three nanomaterials. Conclusion MWCNTs, GO, and RGO were all toxic to zebrafish embryos to influence embryos hatching and larvae length. Although no obvious morphological malformation and mortality were observed in exposed zebrafish embryos, further studies on the toxicity of the three nanomaterials are still needed.
基金Priority Academic Program Development of Jiangsu Higher Education Institutions(2022JSPAPD006)。
文摘OBJECTIVE To assess whether N-acetylcysteine(NAC)and reduced glutathione(GSH)are effective in reversing flupirtine-induced hepatotoxicity and whether they have other beneficial effects when combined with flupirtine.METHODS The analgesic effects of NAC and flupirtine were first evaluated in carrageenaninduced inflammatory pain and paclitaxel-induced neuropathic pain.The combination subthreshold⁃ing approach was then used to determine whether the combination of NAC and flupirtine produced synergistic analgesic effects.Hepatotoxicity markers and histopathological examination of the liver were used to assess the efficacy of NAC and GSH in reversing flupirtine-induced hepato⁃toxicity.Finally,the effect of GSH on the safe range of flupirtine was assessed in an acute tox⁃icity assay.RESULTS Flupirtine and NAC pro⁃duced dose-dependent antiallodynic effects evoked by carrageenan and paclitaxel in mice.In the above model,the combination of NAC and flupirtine produced an unexpected synergistic analgesic effect.There were no significant differ⁃ences observed in the hepatotoxicity markers and liver histopathology between the experimen⁃tal group and the control group under NAC and GSH treatment.Finally,GSH(200 mg·kg^(-1))expanded the therapeutic index of flupirtine by 1.77 times.CONCLUSION NAC and GSH are effective in preventing liver damage caused by long-term flupirtine use,which provides a solu⁃tion for the safe and effective treatment of chronic pain with flupirtine.In addition,the other benefi⁃cial effects of NAC and GSH when combined with flupirtine may provide the basis for the devel⁃opment of a new therapy with minimal sideeffects and good efficacy.
基金Suqian Science and Technology Plan Project(No.Z2019178)。
文摘Objective:To observe the clinical efficacy of dapagliflozin in the treatment of type 2 diabetes mellitus(T2DM)complicated with heart failure with mildly reduced ejection fraction(HFmrEF,40%≤LVEF<50%).Methods:A total of 84 patients with T2DM complicated with HFmrEF hospitalized in our hospital from October 2019 to October 2021 were selected,and random number table method was used to divide into the control group and the study group each 42 cases.Both groups used basal hypoglycemic and standardized anti-heart failure therapy,and the study group was treated with dapagliflozin simultaneously.Nine months later,the following indexes were compared between the two groups before and after treatment:the cardiac function indicators:N-terminal pro brain natriuretic peptide(NT-proBNP),left ventricular ejection fraction(LVEF);exercise endurance:6-minute walk distance(6MWD),NYHA cardiac function class,the score of the Minnesota living with heart failure questionnaire(MLHFQ)and the incidence of major adverse cardiovascular events(MACE).Results:Nine months later,the two groups showed decreased NT-proBNP level,increased LVEF,prolonged 6MWD,improved NYHA cardiac function grade,decreased MLHFQ score,and statistically significant differences within both groups compared with before treatment(P<0.05),after treatment significant differences were displayed between the two groups(P<0.05).Less patients had MACE events and adverse drug reactions in the study group compared with the control group.Conclusion:Dapagliflozin in the treatment of T2DM patients with HFmrEF can improve cardiac function indicators,improve exercise endurance,improve NYHA cardiac function class,improve patient's quality of life,and reduce the incidence of MACE events,with no obvious side effects.
文摘This work presents a comprehensive fourth-order predictive modeling (PM) methodology that uses the MaxEnt principle to incorporate fourth-order moments (means, covariances, skewness, kurtosis) of model parameters, computed and measured model responses, as well as fourth (and higher) order sensitivities of computed model responses to model parameters. This new methodology is designated by the acronym 4<sup>th</sup>-BERRU-PM, which stands for “fourth-order best-estimate results with reduced uncertainties.” The results predicted by the 4<sup>th</sup>-BERRU-PM incorporates, as particular cases, the results previously predicted by the second-order predictive modeling methodology 2<sup>nd</sup>-BERRU-PM, and vastly generalizes the results produced by extant data assimilation and data adjustment procedures.
基金supported by the Guangdong Technical System of Peanut and Soybean Industry(2023KJ136-05)China Agriculture Research System(CARS-15)。
文摘This study investigated the effect of magnesium application on peanut growth and yield under two nitrogen(N)application rates in acidic soil in southern China.The chlorophyll content,net photosynthetic rate and dry matter accumulation of the N-sensitive cultivar decreased under reduced N treatments,whereas no effect was observed on the relevant indicators in the N-insensitive variety GH1026.Mg application increased the net photosynthetic rate by increasing the expression of genes involved in chlorophyll synthesis and Rubisco activity in the leaves during the pegging stage under 50%N treatment,while no effect on the net photosynthetic rate was observed under the 100%N treatment.The rate of dry matter accumulation at the early growth stage,total dry matter accumulation and pod yield at harvest increased after Mg application under 50%N treatment by increasing the transportation of assimilates from stems and leaves to pods in both peanut varieties,whereas no effect was found under 100%N treatment.Moreover,Mg application increased the NUE under 50%N treatment.No improvement of NUE in either peanut variety was found under 100%N treatment,while Mg application under the 50%N treatment can obtain a higher economic benefit than the 100%N treatment.In acidic soil,application of 307.5 kg ha^(-1)of Mg sulfate fertilizer under 50%reduced nitrogen application is a suitable fertilizer management measure for improving carbon assimilation,NUE and achieve high peanut yields in southern China.
文摘Soybean production systems that return plant residues to the soil surface are gaining in popularity. As these practices become more widespread, more crop and weed residues are being introduced into the upper soil profile. Greenhouse studies were conducted to determine the effects of varying concentrations of Palmer amaranth and pitted morningglory plant residues (aboveground portion of the plant) on soybean production. The study was arranged in a completely randomized experimental design with five treatments and five replications. Palmer amaranth and pitted morningglory residues were incorporated into soil at 20,000, 40,000, 80,000 and 160,000 ppm. Inert plastic residue at the same residue levels was included as a check. Soybean dry weight, leaf area and leaf tissue nutrient content were recorded during the study. A decrease in soybean dry weight and leaf area was observed as Palmer amaranth residue in the soil increased. Palmer amaranth residues of 160,000 ppm and 80,000 ppm in the soil significantly reduced soybean dry weight by 69% and 59%, respectively, and soybean leaf area by 60% and 57%, respectively. In contrast, pitted morningglory and inert plastic residues had no observable effect on soybean growth and development. This study demonstrated Palmer amaranth residues in the soil impacted early season soybean growth and development.
基金Supported by Key Laboratory of Financial Mathematics of Fujian Province University(Putian University)(JR202203)the NSF of Anhui Province(2008085MA06).
文摘In this paper,we study reduced rings in which every element is a sum of three tripotents that commute,and determine the integral domains over which every n£n matrix is a sum of three tripotents.It is proved that for an integral domain R,every matrix in M_(n)(R)is a sum of three tripotents if and only if R■Zp with p=2,3,5 or 7.
基金supported by the Universiti Brunei Darussalam Research Funding(Grant No.UBD/OAVCRI/CRGWG(022)/171001).
文摘Three-dimensional(3D)porous absorbents have attracted significant attention in the oily wastewater treatment technology due to their high porosity and elasticity.Given their amphiphilic surface,they have a propensity to simultaneously absorb water and oil,which restricts their range of applications.In this study,a reduced graphene oxide and titanium dioxide nanocomposite(rGO/TiO_(2))was used to fabricate an ultra-hydrophobic melamine sponge(MS)through interfacial modification using a solution immersion technique.To further modify it,poly-dimethylsiloxane(PDMS)was grafted onto its surface to establish stronger covalent bonds with the composite.The water contact angle of the sponge(rGO/TiO_(2)/PDMS/MS)was 164.2°,which satisfies the condition for ultrahydrophobicity.The evidence of its water repellency was demonstrated by the Cassie-Baxter theory and the lotus leaf effect.As a result of the increased density of rGO/TiO_(2)/PDMS/MS,it recorded an initial capacity that was 2 g/g lower than the raw MS for crude oil absorption.The raw MS retained 53% of its initial absorption capacity after 20 cycles of absorption,while rGO/TiO_(2)/PDMS/MS retained 97%,suggesting good recyclability.Excellent oil and organic solvent recovery(90%-96%)was demonstrated by rGO/TiO_(2)/PDMS/MS in oil-water combinations.In a continuous separation system,it achieved a remarkable separation efficiency of 2.4×10^(6)L/(m^(3)·h),and in turbulent emulsion separation,it achieved a demulsification efficiency of 90%-91%.This study provides a practical substitute for massive oil spill cleaning.
文摘In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system complexity.Owing to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and yaw.In response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each step.To cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic angle.In order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control system.In order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step method.The feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition uncertainties.The results indicate that the designed controller can converge to the reference path and evidently decrease the distance between the impact point and target under different uncertainties.
基金supported by the Strategic Research and Consulting Project of Chinese Academy of Engineering(2022-XY-91)the Basic Science Center Project for National Natural Science Foundation of China(72088101)the Key Project of YueLuShan Center Industrial Innovation(2023YCII0105).
文摘The steel industry is considered an important basic sector of the national economy,and its high energy consumption and carbon emissions make it a major contributor to climate change,especially in China.The majority of crude steel in China is produced via the energy-and carbon-intensive blast furnace–basic oxygen furnace(BF–BOF)route,which greatly relies on coking coal.In recent years,China’s steel sector has made significant progress in energy conservation and emission reduction,driven by decarbonization policies and regulations.However,due to the huge output of crude steel,the steel sector still produces 15%of the total national CO_(2) emissions.The direct reduced iron(DRI)plus scrap–electric arc furnace(EAF)process is currently considered a good alternative to the conventional route as a means of reducing CO_(2) emissions and the steel industry’s reliance on iron ore and coking coal,since the gas-based DRI plus scrap–EAF route is expected to be more promising than the coal-based one.Unfortunately,almost no DRI is produced in China,seriously restricting the development of the EAF route.Here,we highlight the challenges and pathways of the future development of DRI,with a focus on China.In the short term,replacing natural gas with coke oven gas(COG)and byproduct gas from the integrated refining and chemical sector is a more economically feasible and cleaner way to develop a gas-based route in China.As the energy revolution proceeds,using fossil fuels in combination with carbon capture,utilization,and storage(CCUS)and hydrogen will be a good alternative due to the relatively low cost.In the long term,DRI is expected to be produced using 100%hydrogen from renewable energy.Both the development of deep processing technologies and the invention of a novel binder are required to prepare high-quality pellets for direct reduction(DR),and further research on the one-step gas-based process is necessary.
基金Funded by the Key R&D Program of the Science and Technology Department of Hubei Province(No.2022BCE008)。
文摘Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface morphology and electric property was investigated.The results confirmed the dense membrane of PEDOT:PSS and the lamellar structure of PDDA-rGO on the fibers.It has excellent electrical conductivity and mechanical properties.The fiber based electrochemical transistor(FECTs)prepared by the composite conductive fiber has a maximum output current of 8.7 mA,a transconductance peak of 10 mS,an on time of 1.37 s,an off time of 1.6 s and excellent switching stability.Most importantly,the devices by layer by layer self-assembly technology opens a path for the true integration of organic electronics with traditional textile technologies and materials,laying the foundation for their later widespread application.
基金the Key Research and Development Program of Hubei Province(2022BCA082 and 2022BCA077).
文摘Due to the low water-cement ratio of ultra-high-performance concrete(UHPC),fluidity and shrinkage cracking are key aspects determining the performance and durability of this type of concrete.In this study,the effects of different types of cementitious materials,chemical shrinkage-reducing agents(SRA)and steel fiber(SF)were assessed.Compared with M2-UHPC and M3-UHPC,M1-UHPC was found to have better fluidity and shrinkage cracking performance.Moreover,different SRA incorporation methods,dosage and different SF types and aspect ratios were implemented.The incorporation of SRA and SF led to a decrease in the fluidity of UHPC.SRA internal content of 1%(NSRA-1%),SRA external content of 1%(WSRA-1%),STS-0.22 and STE-0.7 decreased the fluidity of UHPC by 3.3%,8.3%,9.2%and 25%,respectively.However,SRA and SF improved the UHPC shrinkage cracking performance.NSRA-1%and STE-0.7 reduced the shrinkage value of UHPC by 40%and 60%,respectively,and increased the crack resistance by 338%and 175%,respectively.In addition,the addition of SF was observed to make the microstructure of UHPC more compact,and the compressive strength and flexural strength of 28 d were increased by 26.9%and 19.9%,respectively.
基金supported by the National Key R&D Program of China under Grant No.2021ZD0110400.
文摘Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational domains,etc.Typical reduced order modeling techniques accelerate the solution of the parametric PDEs by projecting them onto a linear trial manifold constructed in the ofline stage.These methods often need a predefined mesh as well as a series of precomputed solution snapshots,and may struggle to balance between the efficiency and accuracy due to the limitation of the linear ansatz.Utilizing the nonlinear representation of neural networks(NNs),we propose the Meta-Auto-Decoder(MAD)to construct a nonlinear trial manifold,whose best possible performance is measured theoretically by the decoder width.Based on the meta-learning concept,the trial manifold can be learned in a mesh-free and unsupervised way during the pre-training stage.Fast adaptation to new(possibly heterogeneous)PDE parameters is enabled by searching on this trial manifold,and optionally fine-tuning the trial manifold at the same time.Extensive numerical experiments show that the MAD method exhibits a faster convergence speed without losing the accuracy than other deep learning-based methods.
基金financial support from the National Natural Science Foundation of China(No.52103223)the Natural Science Basic Research Program of Shaanxi(No.2023-JC-YB-413)+2 种基金the Natural Science Foundation of Heilongjiang Province of China(No.YQ2023E027)the Key Laboratory of Functional Molecular Solids,Ministry of Education(No.FMS20230010)the Fundamental Research Funds for the Central Universities(Nos.3072024GH2605,3072024XX2613,and 3072024XX2616).
文摘Organic–inorganic hybrid perovskites are quite promising candidates in the field of electromagnetic wave (EMW) absorption due to their unique physicochemical properties. However, it is still a considerable challenge to satisfy the light weight, broad bandwidth, and strong absorption properties simultaneously. Herein, the solution of methylammonium lead iodide (MAPbI3) perovskites was infiltrated into the pores of reduced graphene oxide (rGO) aerogels. After drying, a series of MAPbI3/rGO composite aerogel (MGA) materials were synthesized by anchoring the MAPbI3 perovskite nanoparticles to rGO sheets with the assistance of rGO templates. Through the adjustment of component ratios, excellent EMW absorption properties are obtained with the synergistic effects of polarization loss, conduction loss, and multiple reflection and scattering of MAPbI3 and rGO. The porous structure of the aerogel and the suitable group distribution ratio allowed the MGA-4 samples to obtain excellent impedance matching and ultra-low density of ∼ 7.69 mg·cm−3. At a low filling ratio of 15 wt.%, the MGA-4 sample simultaneously achieves highly efficient and broadband EMW absorption performance at a thin thickness. The MGA-4 sample obtained a minimum reflection loss value of −64.35 dB and the effective absorption bandwidth (EAB) value of 5.4 GHz at a thickness of 2.08 mm and a maximum EAB (EABmax) value of 6.2 GHz under 2.22 mm. The MGA-5 sample obtained a maximum EAB value of 6.4 GHz with the thinckness of 2.16 mm. Furthermore, the simulation results of the radar cross-section (RCS) verified the component-optimized composites are capable of achieving excellent EMW attenuation. This paper provides a new approach and valuable reference for the development of hybrid perovskite-based microwave absorption materials with lightweight, ultra-broadband, and strong absorption properties.
基金provided by Guizhou Provincial Science and Technology Projects for Platform and Talent Team Plan(GCC[2023]007)Fok Ying Tung Education Foundation(171095)National Natural Science Foundation of China(11964006).
文摘Considering the serious electromagnetic wave(EMW)pollution problems and complex application condition,there is a pressing need to amalgamate multiple functionalities within a single substance.However,the effective integration of diverse functions into designed EMW absorption materials still faces the huge challenges.Herein,reduced graphene oxide/carbon foams(RGO/CFs)with two-dimensional/three-dimensional(2D/3D)van der Waals(vdWs)heterostructures were meticulously engineered and synthesized utilizing an efficient methodology involving freeze-drying,immersing absorption,secondary freeze-drying,followed by carbonization treatment.Thanks to their excellent linkage effect of amplified dielectric loss and optimized impedance matching,the designed 2D/3D RGO/CFs vdWs heterostructures demonstrated commendable EMW absorption performances,achieving a broad absorption bandwidth of 6.2 GHz and a reflection loss of-50.58 dB with the low matching thicknesses.Furthermore,the obtained 2D/3D RGO/CFs vdWs heterostructures also displayed the significant radar stealth properties,good corrosion resistance performances as well as outstanding thermal insulation capabilities,displaying the great potential in complex and variable environments.Accordingly,this work not only demonstrated a straightforward method for fabricating 2D/3D vdWs heterostructures,but also outlined a powerful mixeddimensional assembly strategy for engineering multifunctional foams for electromagnetic protection,aerospace and other complex conditions.
文摘The effects of sulfate reduced bacterium (SRB) on the corrosion behavior of 10CrMoAl steel in seawater were studied by chemical immersion, potentiodynamic polarization, electrochemical impedance spectroscopy measurement, and scanning electron microscope techniques. The results show that the content of element sulfur in the corrosion product of 10CrMoAl steel in seawater with SRB is up to 9. 23 %, which is higher than that of the same in sterile seawater. X-ray diffraction demonstrates that the main corrosion product is FeS. SRB increases the corrosion rate by anodic depolarization of the metabolized sulfide product. SEM observation indicates that the corrosion product is not distributed continuously; in addition, bacilliform sulfate-reduced bacterium accumulates on the local surface of 10CrMoAl steel. Hence, SRB enhances sensitivity to the localized corrosion of 10CrMoAl steel in seawater.
基金supported by the National Key Research and Development Program of China (No.2021YFB3701100)the Beijing Natural Science Foundation (No.2192006)the National Natural Science Foundation of China (No.51801004).
文摘The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion process.Compared with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal performance.By adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 alloy.The superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with matrix.The strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix composite.The RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.