Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type...Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C.展开更多
By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variationa...By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold.展开更多
The basal ganglia(BG) act as a cohesive functional unit that regulates motor function,habit formation,and reward/addictive behaviors. However,it is still not well understood how the BG maintains wakefulness and suppre...The basal ganglia(BG) act as a cohesive functional unit that regulates motor function,habit formation,and reward/addictive behaviors. However,it is still not well understood how the BG maintains wakefulness and suppresses sleep to achieve al these fundamental functions until genetical y engineered systems developed these years. Significant research efforts have recently been directed at developing genetic-molecular tools to achieve reversible and cell-type specific in vivo silencing or activation of neurons in behaving animals. Optogenetic tools can be used both to specifically activate or inhibit neurons of interest and identify functional synaptic connectivity between specific neuronal populations,both in vivo and in brain slices. Another recently developed system by Roth and colleagues permits the selective and ″remote″ manipulation(activation and silencing) of neuronal activity via all 3 major GPCR signaling pathways(G_i,G_s and G_q). These so-called ″ designer receptors exclusively activated by designer drugs″(DREADD) involve mutant GPCRs that do not respond to their endogenous ligands but are responsive to otherwise inert biological compounds. Recently,we demonstrated the essential roles and the neural pathways of the neurons expressing adenosine A_(2A) receptors or dopamine D_1 receptors in the BG for sleep-wake regulation using the genetically engineered systems including optogenetics and DREADD. We proposed a plausible model in which the caudate-putamen and the nucleus accumbens integrates behavioral processes with sleep/wakefulness through adenosine and dopamine receptors.展开更多
Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda.Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfill...Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda.Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfilled,creating environmental risks either from the generation of dust or migration of filtrates.High alkalinity is the critical factor restricting complete utilization of bauxite residues,whilst the application of alkaline regulation agents is costly and difficult to apply widely.For now,current industrial wastes,such as waste acid,ammonia nitrogen wastewater,waste gypsum and biomass,have become major problems restricting the development of the social economy.Regulation of bauxite residues alkalinity by industrial waste was proposed to achieve‘waste control by waste’with good economic and ecological benefits.This review will focus on the origin and transformation of alkalinity in bauxite residues using typical industrial waste.It will propose key research directions with an emphasis on alkaline regulation by industrial waste,whilst also providing a scientific reference point for their potential use as amendments to enhance soil formation and establish vegetation on bauxite residue disposal areas(BRDAs)following large-scale disposal.展开更多
Alkaline anions,include CO3^2–,HCO3^–,Al(OH)4^–,OH^–,continuously released from bauxite residue(BR),will cause a potential disastrous impact on surrounding environment.The composition variation of alkaline anions,...Alkaline anions,include CO3^2–,HCO3^–,Al(OH)4^–,OH^–,continuously released from bauxite residue(BR),will cause a potential disastrous impact on surrounding environment.The composition variation of alkaline anions,alkaline phase transformation pathway,and micro-morphological transition characteristics during the gypsum addition were investigated in an attempt to understand alkalinity stabilization behavior.Results demonstrated that alkaline anions stabilization degree in leachates can reach approximately 96.29%,whilst pH and alkalinity were reduced from 10.47 to 8.15,47.39 mmol/L to 2 mmol/L,respectively.During the alkalinity stabilization,chemical regulation behavior plays significant role in driving the co-precipitation reaction among the critical alkaline anions(CO3^2–,HCO3^–,Al(OH)4^–,OH^–),with calcium carbonate(CaCO3))being the most prevalent among the transformed alkaline phases.In addition,XRD and SEM-EDX analyses of the solid phase revealed that physical immobilization behavior would also influence the stability of soluble alkali and chemical bonded alkali due to released Ca^2+from gypsum which aggregated the clay particles and stabilized them into coarse particles with a blocky structure.These findings will be beneficial for effectively regulating strong alkalinity of BR.展开更多
To ensure running safety,the secondary spring loads of railway vehicles must be well equalized.Due to the coupling interactive effects of these hyper static suspended structures,the equalization adjustment through shi...To ensure running safety,the secondary spring loads of railway vehicles must be well equalized.Due to the coupling interactive effects of these hyper static suspended structures,the equalization adjustment through shimming procedure is quite complex.Therefore,an effective and reliable method in application is developed in this paper.Firstly,the best regulation of spring load is solved based on a mechanical model of the secondary suspension system,providing a target for actual adjustment.To reveal the relationship between secondary spring load distribution and shim quantity sequence,a forecasting model is constructed and then modified experimentally with consideration of car body’s elastic deformation.Further,a gradient-based algorithm with a momentum operation is proposed for the load optimization.Effectiveness of the whole method has been verified on a test rig.It is experimentally confirmed that this research provides an important basis for achieving an optimal regulation of spring load distribution for multiple types of railway vehicles.展开更多
Embankment stability is the primary problem for the expressway construction in permafrost regions.The proposed Qinghai-Tibet Expressway(QTE)is planned to construct along the Qinghai-Tibet Project Corridor.Confronted w...Embankment stability is the primary problem for the expressway construction in permafrost regions.The proposed Qinghai-Tibet Expressway(QTE)is planned to construct along the Qinghai-Tibet Project Corridor.Confronted with harsh environmental condition and intense heat exchange between earth and atmosphere,it is necessary to predict and evaluate the stability of the proposed QTE.In this study,the factors affecting the embankment stability are analyzed firstly.And then,a scheme for the stability evaluation of the embankment is established.Finally,the evaluation scheme is used for the pre-evaluation of the stability for the proposed QTE with different geothermal regulation measures(GRMs).The results indicate that the influencing factors include climatic environment,permafrost property,engineering condition and geological condition,and among them,engineering condition and permafrost property are the main influence factors for embankment stability.The stability of the proposed QTE varies greatly in the different geomorphological regions.The application effect and contribution to embankment stability of the existing GRMs are different,and using GRMs cannot completely overcome the influence of various factors on expressway stability.In the construction process,different GRMs should be adopted depending on the geomorphological environment where the embankment is located to ensure the embankment stability.展开更多
Transient performance for output regulation problems of linear discrete-time systems with input saturation is addressed by using the composite nonlinear feedback(CNF) control technique. The regulator is designed to ...Transient performance for output regulation problems of linear discrete-time systems with input saturation is addressed by using the composite nonlinear feedback(CNF) control technique. The regulator is designed to be an additive combination of a linear regulator part and a nonlinear feedback part. The linear regulator part solves the regulation problem independently which produces a quick output response but large oscillations. The nonlinear feedback part with well-tuned parameters is introduced to improve the transient performance by smoothing the oscillatory convergence. It is shown that the introduction of the nonlinear feedback part does not change the solvability conditions of the linear discrete-time output regulation problem. The effectiveness of transient improvement is illustrated by a numeric example.展开更多
A fuzzy robust path tracking strategy of an active pelagic trawl system with ship and winch regulation is proposed.First,nonlinear mathematic model of the pelagic trawl system was derived using Lagrange equation and f...A fuzzy robust path tracking strategy of an active pelagic trawl system with ship and winch regulation is proposed.First,nonlinear mathematic model of the pelagic trawl system was derived using Lagrange equation and further simplified as a low order model for the convenience of controller design.Then,an active path tracking strategy of pelagic trawl system was investigated to improve the catching efficiency of the target fish near the sea bottom.By means of the active tracking control,the pelagic trawl net can be positioned dynamically to follow a specified trajectory via the coordinated winch and ship regulation.In addition,considering the system nonlinearities,modeling uncertainties and the unknown exogenous disturbance of the trawl system model,a nonlinear robust H2 /H∞ controller based on Takagi-Sugeno(T-S) fuzzy model was presented,and the simulation comparison with linear robust H2 /H∞ controller and PID method was conducted for the validation of the nonlinear fuzzy robust controller.The nonlinear simulation results show that the average tracking error is 0.4 m for the fuzzy robust H2 /H∞ control and 125.8 m for the vertical and horizontal displacement,respectively,which is much smaller than linear H2 /H∞ controller and the PID controller.The investigation results illustrate that the fuzzy robust controller is effective for the active path tracking control of the pelagic trawl system.展开更多
Atherosclerosis or fibrosis and cirrhosis undergo chronic inflammation associated with the adhesion between neutrophils and endothelial cells(ECs)that is mediated by their respective cellular adhesive molecules on sti...Atherosclerosis or fibrosis and cirrhosis undergo chronic inflammation associated with the adhesion between neutrophils and endothelial cells(ECs)that is mediated by their respective cellular adhesive molecules on stiffened blood vessel wall or extracellular matrix(ECM)under shear flow[1-3].However,the mechanical dependence of calcium flux and trail formation in neutrophils remains unclear yet in these processes.First,the effect of substrate stiffness through ECs on neutrophil calcium spike was quantified when the individual neutrophils adhered to EC monolayer pre-placed onto stiffness-varied polyacrylamide(PA)substrate(5 or 34.88 kPa)or glass surface.Our data indicated that E-/P-selectins and ICAM-1s on HUVECs and b2-integrins,PSGL-1s,and CD44s on neutrophils were all involved in mediating neutrophil calcium spike in a stiffness-dependent manner,in which the increase of substrate stiffness enhanced the calcium intensity and spike number.Such stiffness-dependent calcium response is associated with selectin-induced b2-integrin activation through Syk/Src signaling pathway and the F-actin/myosin II function.Moreover,tension-activated calcium ion channels displayed critical roles in initiating stiffness-dependent calcium spike [4].Second,the trail formation of neutrophils to ECs monolayer pre-placed onto the same PA substrate were also tested under shear flow.Live fluorescence imaging showed that neutrophils are able to form long membrane tethers during migration and subsequently leave behind membranous long-lasting trails under shear,which are enriched in LFA-1,Mac-1,and CD44.Moreover,the formation of the trails was inhibited by blocking LFA-1s and Mac-1s,suggesting an important role forβ2-integrins in the trial formation.The recruitment of monocytes was inhibited when pre-blocking ICAM-1s on flowing monocytes,indicating that the neutrophil’s trails employβ2-integrin-ICAM-1 binding to recruit the monocytes.Intriguingly,both the length and the area of the trails increase with increasing substrate stiffness,resulting in the enhanced monocyte recruitment.Inhibition of actin binding protein Arp2/3 impairs the trail formation and dramatically decreases the neutrophil-dependent monocyte recruitment.These data provide an insight into understanding how stiffening of vascular wall could regulate the calcium flux of adhered neutrophils and thus the immune responses in atherosclerosis.They also imply that local mechanical microenvironment is remodeled with the migration of neutrophils,leaving the trails presented to induce and regulate monocyte recruitment.All the results are meaningful in elucidating the occurrence and development of atherosclerosis or fibrosis from the viewpoint of mechanotransduction and also for the potential intervention of cardiovascular disease progress.展开更多
Objective The binding of cell adhesive peptides(such as RGD)to integrins initiates the recruitment of cytoplasmic adaptor proteins(e.g.,vinculin)and the formation of focal adhesion(FA)complexes required for cell adhes...Objective The binding of cell adhesive peptides(such as RGD)to integrins initiates the recruitment of cytoplasmic adaptor proteins(e.g.,vinculin)and the formation of focal adhesion(FA)complexes required for cell adhesion.The ability to manipulate this ligand-mediated cell adhesion process is crucial for regulating cell migration,cell differentiation,injury healing,and immune response.Some recent studies reported the importance of the tether length/mobility of the cell adhesive ligands in regulating the traction force development of cells.In the native cellular microenvironment,such a dynamic change in the nanoscale tether length of bioactive ligands is often mediated by conformational changes of the structural proteins due to protein folding or degradation.However,no prior studies have demonstrated the modulation of the ligand tether mobility by controlling the intramolecular folding of polymeric linkers.Unfoldable synthetic macromolecules with easy synthetic routes and controllable structures,such as supramolecular host-guest single chain nanogels(SCNGs),are ideal candidates for mimicking the changes in the tether mobility of bioactive ligands via biorthogonal triggers.Methods S,S’-bis(a’a’-dimethyl-a’’-propargyl acetate)trithiocarbonate was first used to mediate the RAFT polymerization of N,N-dimethyl acrylamide,vinyl-adamantane and vinyl-β-cyclodextrin to yield the ADA@CD-SCNGs.The preparation of the unfoldable host-guest SCNGs was evidenced by the by gel permeation chromatography,proton nuclear magnetic resonance spectroscopy,atomic force microscopy and dynamic light scattering.Then the RGD peptide was conjugated to the alkynyl group on one end of the SCNGs before immobilizing the material on the substrate,which was confirmed by scanning electron microscopy(SEM).The regulation of cell behaviours by unfolding of the SCNG-RGD was confirmed by immunofluorescence staining of vinculin and Yes-associated protein(YAP).Results The preparation of ADA@CD-SCNGs was confirmed by GPC which showed a unimodal molecular weight distribution.DLS and AFM data also proved that the SCNGs had an average diameter of 12±3nm.SEM images showed that SCNGs were conjugated as a linker of RGD peptide to thiolated glass substrate at an average density of 162±11 particles/μm2.These particles disappeared after adding free competitive ADA guest molecules,indicating the triggered unfolding of the tether SCNGs.In addition,the unfolding of supramolecular ADA@CD-SCNGs was also evidenced by a decrease in the GPC elution time and a slight increase in the apparent molecular weight.These results show that the immobilized ADA@CD-SCNGs can be unfolded to tune the tether length and mobility of the conjugated RGD ligands.Then we investigated the regulation of the cell behaviors on the substrate by triggering the unfolding of SCNG linkers.A critical level of traction force is required to effectively initiate and maintain integrin-mediated formation of FA complexes and subsequent mechano-transduction signaling.An increased tether length in cell-adhesive ligands can lead to a diminished cell traction force as if cells are adhering to soft substrates.Here,the unfolding of the ADA@CD-SCNG-RGD triggered by the addition of free ADA led to disassembly of the mature focal adhesions in the cells as evidenced by the reduced vinculin and F-actin in staining.Subsequently,nuclear YAP also decreased significantly because of the impaired mechano-sensing and diminished cell cytoskeleton tension.In addition,the extensively spread cells gradually became round after the medium was supplemented with free competitive ADA to unfold the SCNG linker.These finding demonstrates that the substrates with the unfolded ADA@CD-SCNG-RGD only supported weak cell adhesions.In contrast,on the substrate conjugated with the nonunfoldable MBA-SCNG-RGD linker,the addition of free ADA resulted in no change in the spread cell morphology and protein expressions.These results indicate that the unfoldable host-guest ADA@CD-SCNG can be used to manipulate the nanoscale presentation of ligands to regulate cell behaviors.Conclusions We demonstrate the application of SCNGs as the supramolecular linker to tune the nanoscale ligand tether length.These findings demonstrate that the strategy of manipulating the tether mobility of bioactive ligands by using supramolecular SCNGs as linkers provides a highly tunable,biomimetic,and bio-orthogonal approach to study the dynamic events of cell adhesion.展开更多
This paper looks at the progressive impact of UK Building Regulations (Part L) on the energy consumption of dwellings with respect to thermal performance of the building envelope. It provides an overview of building l...This paper looks at the progressive impact of UK Building Regulations (Part L) on the energy consumption of dwellings with respect to thermal performance of the building envelope. It provides an overview of building legislation,highlighting progressive improvement in building elemental U-values and compliance methods. The focus centres on Building Regulations from 1965 to 2006,at a time when energy conservation has become an integral component of building control due to environmental concerns. Simulation software is used to compare energy consumption for 5 typical UK dwelling types through a series of case studies which illustrate the rate of impact over recent years.展开更多
OBJECTIVE To investigate the role of e IF3a in the regulation of DNA repair pathways in cancer chemotherapeutic response.METHODS Immunohistochemistry was used to determine the expression of e IF3a in lung and breast c...OBJECTIVE To investigate the role of e IF3a in the regulation of DNA repair pathways in cancer chemotherapeutic response.METHODS Immunohistochemistry was used to determine the expression of e IF3a in lung and breast cancer tissues followed by association analysis of e IF3a expression with patient′s response to chemotherapy.Ectopic overexpression and RNA interference knockdown of e IF3a were carried out in NIH3T3and H1299 cell lines,respectively,to determine the effect of altered e IF3a expression on cellular response to chemotherapeutic drugs by using MTT assay.The DNA repair capacity of these cells was evaluated by using host-cell reactivation,NHEJ and HR assay.Real-time reverse transcriptase PCR and Western Blot analyses were carried out to determine the effect of e IF3a on the DNA repair genes by using cells with altered e IF3a expression.RESULTS e IF3a expression associates with response of lung and breast cancer patients to platinum and anthracycline.e IF3a knockdown or overexpression,respectively,increased and decreased the cellular resistance to cisplatin and anthracycline anticancer drugs,DNA repair activity,and expression of NER and NHEJ DNA repair proteins.CONCLUSION e IF3a plays an important role in regulating the expression of NER and NHEJ DNA repair proteins which,in turn,contributes to cellular response to DNA-damaging anticancer drugs and patients′response to platinum and anthracycline chemotherapy.展开更多
Introduction Excessive narrowing of airways is the most important pathological feature of asthma,but its mechanism remains puzzling.One certain thing is that the contraction of airway smooth muscle(ASM)ultimately caus...Introduction Excessive narrowing of airways is the most important pathological feature of asthma,but its mechanism remains puzzling.One certain thing is that the contraction of airway smooth muscle(ASM)ultimately causes airway narrowing,thus both structural and functional alterations of airway smooth muscle(ASM)are thought as common final pathway responsible for the bronchial hyperresponsiveness(BHR),the hall mark of asthma.Many chemical and physical factors such as air pollutants,inflammatory agents,mechanical and geometrical properties of the microenvironment could influence structure and/or function of ASM cells.In addition,some re-展开更多
This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem wit...This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem with a prospected property can be transformed to a robust stabilization problem with a new output constraint.Then,by constructing the speed function and adopting barrier Lyapunov function technique,the dynamic feedback controller can be designed not only to drive error output of the closed-loop system entering into a prescribed performance bound within a given finite time,but also to achieve that the error output converges to zero asymptotically.The effectiveness of the results is illustrated by a simulation example.展开更多
The global robust output regulation problem of the singular nonlinear system is investigated. Motivated by the input-output linearization of the normal affine nonlinear system, a global diffeomorphism map is designed ...The global robust output regulation problem of the singular nonlinear system is investigated. Motivated by the input-output linearization of the normal affine nonlinear system, a global diffeomorphism map is designed under the assumption that the singular nonlinear system has a strong relative degree. The global diffeomorphism map transfers the singular nonlinear system into a new singular nonlinear system with a special structure. Attaching an internal model to the new singular nonlinear system yields an augmented singular nonlinear system and the global robust stabilization solution of the augmented system implies the global robust output regulation solution of the original singular nonlinear system. Then the global stabilization problem is solved by some appropriate assumptions and the solvability conditions of the global robust output regulation problem are established. Finally, a simulation example is given to illustrate the design approach.展开更多
OBJECTIVE Two-pore domain potassium channel subtype TREK-1 was widely proved to be activated by inhalational anesthet⁃ics such as chloroform,diethyl ether,halothane,and isoflurane.But little is known about whether TRE...OBJECTIVE Two-pore domain potassium channel subtype TREK-1 was widely proved to be activated by inhalational anesthet⁃ics such as chloroform,diethyl ether,halothane,and isoflurane.But little is known about whether TREK-1 was also a potentially important target of intravenous anesthetics.Etomidate is a popularly used intravenous anesthetic with good safety in clinic.The action of etomidate on TREK-1 was seldom reported.METHODS AND RESULTS By using patch-clamp whole-cell recording tech⁃niques,we found for the first time that etomidate could bidirectionally regulate the TREK-1 potassi⁃um channel in CHO/TREK-1 cells.TREK-1 current amplitudes were observed after the administra⁃tion of etomidate at concentrations ranging from 3 to 100μmol·L-1.Etomidate activated TREK-1 current at concentrations of 3,10,and 15μmol·L-1 with maximum activation at 10μmol·L-1.Interest⁃ingly,at higher concentrations from 20 to 100μmol·L-1,etomidate inhibited TREK-1 current in a concentration-dependent way.According to the concentration-response curve,the fitted criti⁃cal concentration of etomidate between TREK-1 activation and inhibition was 20.7μmol·L-1,which close to the result that etomidate had no obvious effect on TREK-1 at 20μmol·L-1.In addition,etomidate 10μmol·L-1 induced a significant mem⁃brane potential hyperpolarization while etomidate 30μmol·L-1 showed obvious membrane potential depolarization.Furthermore,the bidirectional regulation still existed when the extracellular pH of CHO/TREK-1 cells was decreased.CONCLUSION TREK-1 is activated by etomi⁃date at clinically relevant concentrations but inhib⁃ited by supraclinical concentrations of etomidate,which is different to other volatile anesthetics.TREK-1 might be a potential target for anesthetic such as etomidate and the complicated bidirec⁃tional regulation mechanism of etomidate needed to be fully studied in the future.展开更多
The mammalian target of rapamycin (mTOR) signaling pathway is evolutionarily conserved, mTOR can integrate and converge a wide range of signals, including intracellular and extracellular nutrients, growth factors, e...The mammalian target of rapamycin (mTOR) signaling pathway is evolutionarily conserved, mTOR can integrate and converge a wide range of signals, including intracellular and extracellular nutrients, growth factors, energy and stress conditions, and has a crucial role in the vertebrate growth control. This review analyzed the main components and regulated factors of TOR signaling pathway, explained functions and mechanisms of roTOR during the individual growth, the development and its dynamic role, revealed its additional functions beyond the cell growth control, and finally reviewed the tissue specificity and time specificity of mTOR signaling pathway, and its regulation on sexual differentiation, tissue differentiation and organogenesis in the individual development.展开更多
Nitrate Reductase (NR) is a rating-limit and key enzyme of nitrate assimilation in plants,so,NR activity is important for growth,development and the dry matter accumulation of plants.The regulation of NR activity appe...Nitrate Reductase (NR) is a rating-limit and key enzyme of nitrate assimilation in plants,so,NR activity is important for growth,development and the dry matter accumulation of plants.The regulation of NR activity appears to be rather complex and many studies have been devoted to the description of regulation and properties,but in this paper we focus on the properties and regulation of NR in higher plants.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.52272208,22309057)the Natural Science Foundation of Hubei Province(Grant No.2023AFB355)the Fundamental Research Funds for the Central Universities of China(Grant No.2662022LXQD001).
文摘Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C.
文摘By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold.
文摘The basal ganglia(BG) act as a cohesive functional unit that regulates motor function,habit formation,and reward/addictive behaviors. However,it is still not well understood how the BG maintains wakefulness and suppresses sleep to achieve al these fundamental functions until genetical y engineered systems developed these years. Significant research efforts have recently been directed at developing genetic-molecular tools to achieve reversible and cell-type specific in vivo silencing or activation of neurons in behaving animals. Optogenetic tools can be used both to specifically activate or inhibit neurons of interest and identify functional synaptic connectivity between specific neuronal populations,both in vivo and in brain slices. Another recently developed system by Roth and colleagues permits the selective and ″remote″ manipulation(activation and silencing) of neuronal activity via all 3 major GPCR signaling pathways(G_i,G_s and G_q). These so-called ″ designer receptors exclusively activated by designer drugs″(DREADD) involve mutant GPCRs that do not respond to their endogenous ligands but are responsive to otherwise inert biological compounds. Recently,we demonstrated the essential roles and the neural pathways of the neurons expressing adenosine A_(2A) receptors or dopamine D_1 receptors in the BG for sleep-wake regulation using the genetically engineered systems including optogenetics and DREADD. We proposed a plausible model in which the caudate-putamen and the nucleus accumbens integrates behavioral processes with sleep/wakefulness through adenosine and dopamine receptors.
基金Projects(41877551,41842020)supported by the National Natural Science Foundation of ChinaProject(201509048)supported by the Environmental Protection’s Special Scientific Research for Chinese Public Welfare Industry
文摘Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda.Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfilled,creating environmental risks either from the generation of dust or migration of filtrates.High alkalinity is the critical factor restricting complete utilization of bauxite residues,whilst the application of alkaline regulation agents is costly and difficult to apply widely.For now,current industrial wastes,such as waste acid,ammonia nitrogen wastewater,waste gypsum and biomass,have become major problems restricting the development of the social economy.Regulation of bauxite residues alkalinity by industrial waste was proposed to achieve‘waste control by waste’with good economic and ecological benefits.This review will focus on the origin and transformation of alkalinity in bauxite residues using typical industrial waste.It will propose key research directions with an emphasis on alkaline regulation by industrial waste,whilst also providing a scientific reference point for their potential use as amendments to enhance soil formation and establish vegetation on bauxite residue disposal areas(BRDAs)following large-scale disposal.
基金Project(41877511)supported by the National Natural Science Foundation of ChinaProject(201509048)supported by the Environmental Protection’s Special Scientific Research for the Chinese Public Welfare Industry,China
文摘Alkaline anions,include CO3^2–,HCO3^–,Al(OH)4^–,OH^–,continuously released from bauxite residue(BR),will cause a potential disastrous impact on surrounding environment.The composition variation of alkaline anions,alkaline phase transformation pathway,and micro-morphological transition characteristics during the gypsum addition were investigated in an attempt to understand alkalinity stabilization behavior.Results demonstrated that alkaline anions stabilization degree in leachates can reach approximately 96.29%,whilst pH and alkalinity were reduced from 10.47 to 8.15,47.39 mmol/L to 2 mmol/L,respectively.During the alkalinity stabilization,chemical regulation behavior plays significant role in driving the co-precipitation reaction among the critical alkaline anions(CO3^2–,HCO3^–,Al(OH)4^–,OH^–),with calcium carbonate(CaCO3))being the most prevalent among the transformed alkaline phases.In addition,XRD and SEM-EDX analyses of the solid phase revealed that physical immobilization behavior would also influence the stability of soluble alkali and chemical bonded alkali due to released Ca^2+from gypsum which aggregated the clay particles and stabilized them into coarse particles with a blocky structure.These findings will be beneficial for effectively regulating strong alkalinity of BR.
基金Project(51305467)supported by the National Natural Science Foundation of ChinaProject(12JJ4050)supported by the Natural Science Foundation of Hunan Province,China
文摘To ensure running safety,the secondary spring loads of railway vehicles must be well equalized.Due to the coupling interactive effects of these hyper static suspended structures,the equalization adjustment through shimming procedure is quite complex.Therefore,an effective and reliable method in application is developed in this paper.Firstly,the best regulation of spring load is solved based on a mechanical model of the secondary suspension system,providing a target for actual adjustment.To reveal the relationship between secondary spring load distribution and shim quantity sequence,a forecasting model is constructed and then modified experimentally with consideration of car body’s elastic deformation.Further,a gradient-based algorithm with a momentum operation is proposed for the load optimization.Effectiveness of the whole method has been verified on a test rig.It is experimentally confirmed that this research provides an important basis for achieving an optimal regulation of spring load distribution for multiple types of railway vehicles.
基金Project(2019QZKK0905)supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)Program,ChinaProject(41901074)supported by the National Natural Science Foundation of China+2 种基金Project(2020A1515010745)supported by the Natural Science Foundation of Guangdong Province,ChinaProject(SKLFSE201810)supported by the Open Fund of the State Key Laboratory of Frozen Soil Engineering,ChinaProject(2019MS119)supported by the Fundamental Research Funds for the Central Universities,China。
文摘Embankment stability is the primary problem for the expressway construction in permafrost regions.The proposed Qinghai-Tibet Expressway(QTE)is planned to construct along the Qinghai-Tibet Project Corridor.Confronted with harsh environmental condition and intense heat exchange between earth and atmosphere,it is necessary to predict and evaluate the stability of the proposed QTE.In this study,the factors affecting the embankment stability are analyzed firstly.And then,a scheme for the stability evaluation of the embankment is established.Finally,the evaluation scheme is used for the pre-evaluation of the stability for the proposed QTE with different geothermal regulation measures(GRMs).The results indicate that the influencing factors include climatic environment,permafrost property,engineering condition and geological condition,and among them,engineering condition and permafrost property are the main influence factors for embankment stability.The stability of the proposed QTE varies greatly in the different geomorphological regions.The application effect and contribution to embankment stability of the existing GRMs are different,and using GRMs cannot completely overcome the influence of various factors on expressway stability.In the construction process,different GRMs should be adopted depending on the geomorphological environment where the embankment is located to ensure the embankment stability.
基金supported by the National Natural Science Foundation of China(61074004)the Research Fund for the Doctoral Program of Higher Education(20110121110017)
文摘Transient performance for output regulation problems of linear discrete-time systems with input saturation is addressed by using the composite nonlinear feedback(CNF) control technique. The regulator is designed to be an additive combination of a linear regulator part and a nonlinear feedback part. The linear regulator part solves the regulation problem independently which produces a quick output response but large oscillations. The nonlinear feedback part with well-tuned parameters is introduced to improve the transient performance by smoothing the oscillatory convergence. It is shown that the introduction of the nonlinear feedback part does not change the solvability conditions of the linear discrete-time output regulation problem. The effectiveness of transient improvement is illustrated by a numeric example.
基金Project(2009AA045004)supported by the Hi-tech Research and Development Program of China
文摘A fuzzy robust path tracking strategy of an active pelagic trawl system with ship and winch regulation is proposed.First,nonlinear mathematic model of the pelagic trawl system was derived using Lagrange equation and further simplified as a low order model for the convenience of controller design.Then,an active path tracking strategy of pelagic trawl system was investigated to improve the catching efficiency of the target fish near the sea bottom.By means of the active tracking control,the pelagic trawl net can be positioned dynamically to follow a specified trajectory via the coordinated winch and ship regulation.In addition,considering the system nonlinearities,modeling uncertainties and the unknown exogenous disturbance of the trawl system model,a nonlinear robust H2 /H∞ controller based on Takagi-Sugeno(T-S) fuzzy model was presented,and the simulation comparison with linear robust H2 /H∞ controller and PID method was conducted for the validation of the nonlinear fuzzy robust controller.The nonlinear simulation results show that the average tracking error is 0.4 m for the fuzzy robust H2 /H∞ control and 125.8 m for the vertical and horizontal displacement,respectively,which is much smaller than linear H2 /H∞ controller and the PID controller.The investigation results illustrate that the fuzzy robust controller is effective for the active path tracking control of the pelagic trawl system.
基金supported by National Natural Science Foundation of China Grant( 31627804,91642203, 11772345,91539119)Chinese Academy of Sciences Strategic Priority Research Program ( XDB22040101)Frontier Science Key Project( QYZDJ-SSWJSC018)
文摘Atherosclerosis or fibrosis and cirrhosis undergo chronic inflammation associated with the adhesion between neutrophils and endothelial cells(ECs)that is mediated by their respective cellular adhesive molecules on stiffened blood vessel wall or extracellular matrix(ECM)under shear flow[1-3].However,the mechanical dependence of calcium flux and trail formation in neutrophils remains unclear yet in these processes.First,the effect of substrate stiffness through ECs on neutrophil calcium spike was quantified when the individual neutrophils adhered to EC monolayer pre-placed onto stiffness-varied polyacrylamide(PA)substrate(5 or 34.88 kPa)or glass surface.Our data indicated that E-/P-selectins and ICAM-1s on HUVECs and b2-integrins,PSGL-1s,and CD44s on neutrophils were all involved in mediating neutrophil calcium spike in a stiffness-dependent manner,in which the increase of substrate stiffness enhanced the calcium intensity and spike number.Such stiffness-dependent calcium response is associated with selectin-induced b2-integrin activation through Syk/Src signaling pathway and the F-actin/myosin II function.Moreover,tension-activated calcium ion channels displayed critical roles in initiating stiffness-dependent calcium spike [4].Second,the trail formation of neutrophils to ECs monolayer pre-placed onto the same PA substrate were also tested under shear flow.Live fluorescence imaging showed that neutrophils are able to form long membrane tethers during migration and subsequently leave behind membranous long-lasting trails under shear,which are enriched in LFA-1,Mac-1,and CD44.Moreover,the formation of the trails was inhibited by blocking LFA-1s and Mac-1s,suggesting an important role forβ2-integrins in the trial formation.The recruitment of monocytes was inhibited when pre-blocking ICAM-1s on flowing monocytes,indicating that the neutrophil’s trails employβ2-integrin-ICAM-1 binding to recruit the monocytes.Intriguingly,both the length and the area of the trails increase with increasing substrate stiffness,resulting in the enhanced monocyte recruitment.Inhibition of actin binding protein Arp2/3 impairs the trail formation and dramatically decreases the neutrophil-dependent monocyte recruitment.These data provide an insight into understanding how stiffening of vascular wall could regulate the calcium flux of adhered neutrophils and thus the immune responses in atherosclerosis.They also imply that local mechanical microenvironment is remodeled with the migration of neutrophils,leaving the trails presented to induce and regulate monocyte recruitment.All the results are meaningful in elucidating the occurrence and development of atherosclerosis or fibrosis from the viewpoint of mechanotransduction and also for the potential intervention of cardiovascular disease progress.
文摘Objective The binding of cell adhesive peptides(such as RGD)to integrins initiates the recruitment of cytoplasmic adaptor proteins(e.g.,vinculin)and the formation of focal adhesion(FA)complexes required for cell adhesion.The ability to manipulate this ligand-mediated cell adhesion process is crucial for regulating cell migration,cell differentiation,injury healing,and immune response.Some recent studies reported the importance of the tether length/mobility of the cell adhesive ligands in regulating the traction force development of cells.In the native cellular microenvironment,such a dynamic change in the nanoscale tether length of bioactive ligands is often mediated by conformational changes of the structural proteins due to protein folding or degradation.However,no prior studies have demonstrated the modulation of the ligand tether mobility by controlling the intramolecular folding of polymeric linkers.Unfoldable synthetic macromolecules with easy synthetic routes and controllable structures,such as supramolecular host-guest single chain nanogels(SCNGs),are ideal candidates for mimicking the changes in the tether mobility of bioactive ligands via biorthogonal triggers.Methods S,S’-bis(a’a’-dimethyl-a’’-propargyl acetate)trithiocarbonate was first used to mediate the RAFT polymerization of N,N-dimethyl acrylamide,vinyl-adamantane and vinyl-β-cyclodextrin to yield the ADA@CD-SCNGs.The preparation of the unfoldable host-guest SCNGs was evidenced by the by gel permeation chromatography,proton nuclear magnetic resonance spectroscopy,atomic force microscopy and dynamic light scattering.Then the RGD peptide was conjugated to the alkynyl group on one end of the SCNGs before immobilizing the material on the substrate,which was confirmed by scanning electron microscopy(SEM).The regulation of cell behaviours by unfolding of the SCNG-RGD was confirmed by immunofluorescence staining of vinculin and Yes-associated protein(YAP).Results The preparation of ADA@CD-SCNGs was confirmed by GPC which showed a unimodal molecular weight distribution.DLS and AFM data also proved that the SCNGs had an average diameter of 12±3nm.SEM images showed that SCNGs were conjugated as a linker of RGD peptide to thiolated glass substrate at an average density of 162±11 particles/μm2.These particles disappeared after adding free competitive ADA guest molecules,indicating the triggered unfolding of the tether SCNGs.In addition,the unfolding of supramolecular ADA@CD-SCNGs was also evidenced by a decrease in the GPC elution time and a slight increase in the apparent molecular weight.These results show that the immobilized ADA@CD-SCNGs can be unfolded to tune the tether length and mobility of the conjugated RGD ligands.Then we investigated the regulation of the cell behaviors on the substrate by triggering the unfolding of SCNG linkers.A critical level of traction force is required to effectively initiate and maintain integrin-mediated formation of FA complexes and subsequent mechano-transduction signaling.An increased tether length in cell-adhesive ligands can lead to a diminished cell traction force as if cells are adhering to soft substrates.Here,the unfolding of the ADA@CD-SCNG-RGD triggered by the addition of free ADA led to disassembly of the mature focal adhesions in the cells as evidenced by the reduced vinculin and F-actin in staining.Subsequently,nuclear YAP also decreased significantly because of the impaired mechano-sensing and diminished cell cytoskeleton tension.In addition,the extensively spread cells gradually became round after the medium was supplemented with free competitive ADA to unfold the SCNG linker.These finding demonstrates that the substrates with the unfolded ADA@CD-SCNG-RGD only supported weak cell adhesions.In contrast,on the substrate conjugated with the nonunfoldable MBA-SCNG-RGD linker,the addition of free ADA resulted in no change in the spread cell morphology and protein expressions.These results indicate that the unfoldable host-guest ADA@CD-SCNG can be used to manipulate the nanoscale presentation of ligands to regulate cell behaviors.Conclusions We demonstrate the application of SCNGs as the supramolecular linker to tune the nanoscale ligand tether length.These findings demonstrate that the strategy of manipulating the tether mobility of bioactive ligands by using supramolecular SCNGs as linkers provides a highly tunable,biomimetic,and bio-orthogonal approach to study the dynamic events of cell adhesion.
基金Project supported by UK Engineering and Physical Sciences Research Council (EPSRC) Doctoral Training Grant Scheme
文摘This paper looks at the progressive impact of UK Building Regulations (Part L) on the energy consumption of dwellings with respect to thermal performance of the building envelope. It provides an overview of building legislation,highlighting progressive improvement in building elemental U-values and compliance methods. The focus centres on Building Regulations from 1965 to 2006,at a time when energy conservation has become an integral component of building control due to environmental concerns. Simulation software is used to compare energy consumption for 5 typical UK dwelling types through a series of case studies which illustrate the rate of impact over recent years.
基金The project supported by National High-tech R&D Program of China 863 Program Grant(2009AA022704)National Natural Science Foundation of China(81573463,81173129,81202595 and NIH Grant CA 94961)
文摘OBJECTIVE To investigate the role of e IF3a in the regulation of DNA repair pathways in cancer chemotherapeutic response.METHODS Immunohistochemistry was used to determine the expression of e IF3a in lung and breast cancer tissues followed by association analysis of e IF3a expression with patient′s response to chemotherapy.Ectopic overexpression and RNA interference knockdown of e IF3a were carried out in NIH3T3and H1299 cell lines,respectively,to determine the effect of altered e IF3a expression on cellular response to chemotherapeutic drugs by using MTT assay.The DNA repair capacity of these cells was evaluated by using host-cell reactivation,NHEJ and HR assay.Real-time reverse transcriptase PCR and Western Blot analyses were carried out to determine the effect of e IF3a on the DNA repair genes by using cells with altered e IF3a expression.RESULTS e IF3a expression associates with response of lung and breast cancer patients to platinum and anthracycline.e IF3a knockdown or overexpression,respectively,increased and decreased the cellular resistance to cisplatin and anthracycline anticancer drugs,DNA repair activity,and expression of NER and NHEJ DNA repair proteins.CONCLUSION e IF3a plays an important role in regulating the expression of NER and NHEJ DNA repair proteins which,in turn,contributes to cellular response to DNA-damaging anticancer drugs and patients′response to platinum and anthracycline chemotherapy.
基金supported by National Natural Science Foundation of China(Grant No. 11172340)Training Program for Hundreds of Distinguished Leading Scientists of Chongqing+3 种基金Chongqing Natural Science Foundation(Grant No.CSTC2010BA5001,CSTC2012jjA0588)Fundamental Research Funds for the Central Universities(Grant No.CQDXWL-2012-123)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20120191120032)Sharing Fund of Chongqing University's LargeScale Equipment(Grant No.2010063057,2011063048,2011063049)
文摘Introduction Excessive narrowing of airways is the most important pathological feature of asthma,but its mechanism remains puzzling.One certain thing is that the contraction of airway smooth muscle(ASM)ultimately causes airway narrowing,thus both structural and functional alterations of airway smooth muscle(ASM)are thought as common final pathway responsible for the bronchial hyperresponsiveness(BHR),the hall mark of asthma.Many chemical and physical factors such as air pollutants,inflammatory agents,mechanical and geometrical properties of the microenvironment could influence structure and/or function of ASM cells.In addition,some re-
基金supported by the National Natural Science Foundation of China(61873219)。
文摘This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem with a prospected property can be transformed to a robust stabilization problem with a new output constraint.Then,by constructing the speed function and adopting barrier Lyapunov function technique,the dynamic feedback controller can be designed not only to drive error output of the closed-loop system entering into a prescribed performance bound within a given finite time,but also to achieve that the error output converges to zero asymptotically.The effectiveness of the results is illustrated by a simulation example.
基金supported by the National Natural Science Foundation of China(61374035)the Fundamental Research Funds for the Central Universities(20720150177)
文摘The global robust output regulation problem of the singular nonlinear system is investigated. Motivated by the input-output linearization of the normal affine nonlinear system, a global diffeomorphism map is designed under the assumption that the singular nonlinear system has a strong relative degree. The global diffeomorphism map transfers the singular nonlinear system into a new singular nonlinear system with a special structure. Attaching an internal model to the new singular nonlinear system yields an augmented singular nonlinear system and the global robust stabilization solution of the augmented system implies the global robust output regulation solution of the original singular nonlinear system. Then the global stabilization problem is solved by some appropriate assumptions and the solvability conditions of the global robust output regulation problem are established. Finally, a simulation example is given to illustrate the design approach.
文摘OBJECTIVE Two-pore domain potassium channel subtype TREK-1 was widely proved to be activated by inhalational anesthet⁃ics such as chloroform,diethyl ether,halothane,and isoflurane.But little is known about whether TREK-1 was also a potentially important target of intravenous anesthetics.Etomidate is a popularly used intravenous anesthetic with good safety in clinic.The action of etomidate on TREK-1 was seldom reported.METHODS AND RESULTS By using patch-clamp whole-cell recording tech⁃niques,we found for the first time that etomidate could bidirectionally regulate the TREK-1 potassi⁃um channel in CHO/TREK-1 cells.TREK-1 current amplitudes were observed after the administra⁃tion of etomidate at concentrations ranging from 3 to 100μmol·L-1.Etomidate activated TREK-1 current at concentrations of 3,10,and 15μmol·L-1 with maximum activation at 10μmol·L-1.Interest⁃ingly,at higher concentrations from 20 to 100μmol·L-1,etomidate inhibited TREK-1 current in a concentration-dependent way.According to the concentration-response curve,the fitted criti⁃cal concentration of etomidate between TREK-1 activation and inhibition was 20.7μmol·L-1,which close to the result that etomidate had no obvious effect on TREK-1 at 20μmol·L-1.In addition,etomidate 10μmol·L-1 induced a significant mem⁃brane potential hyperpolarization while etomidate 30μmol·L-1 showed obvious membrane potential depolarization.Furthermore,the bidirectional regulation still existed when the extracellular pH of CHO/TREK-1 cells was decreased.CONCLUSION TREK-1 is activated by etomi⁃date at clinically relevant concentrations but inhib⁃ited by supraclinical concentrations of etomidate,which is different to other volatile anesthetics.TREK-1 might be a potential target for anesthetic such as etomidate and the complicated bidirec⁃tional regulation mechanism of etomidate needed to be fully studied in the future.
文摘The mammalian target of rapamycin (mTOR) signaling pathway is evolutionarily conserved, mTOR can integrate and converge a wide range of signals, including intracellular and extracellular nutrients, growth factors, energy and stress conditions, and has a crucial role in the vertebrate growth control. This review analyzed the main components and regulated factors of TOR signaling pathway, explained functions and mechanisms of roTOR during the individual growth, the development and its dynamic role, revealed its additional functions beyond the cell growth control, and finally reviewed the tissue specificity and time specificity of mTOR signaling pathway, and its regulation on sexual differentiation, tissue differentiation and organogenesis in the individual development.
文摘Nitrate Reductase (NR) is a rating-limit and key enzyme of nitrate assimilation in plants,so,NR activity is important for growth,development and the dry matter accumulation of plants.The regulation of NR activity appears to be rather complex and many studies have been devoted to the description of regulation and properties,but in this paper we focus on the properties and regulation of NR in higher plants.