Polygonati Rhizoma,a functional food and a traditional Chinese medicine broadly used in China and several Southeast Asia countries,possesses effective health-promoting activities.Prepared from 3 plants in Polygonatum ...Polygonati Rhizoma,a functional food and a traditional Chinese medicine broadly used in China and several Southeast Asia countries,possesses effective health-promoting activities.Prepared from 3 plants in Polygonatum genus(Polygonatum kingianum,Polygonatum sibiricum,and Polygonatum cyrtonema),Polygonati Rhizoma has drawn increasing attention due to its remarkable immune-enhancing and metabolic regulatory activities in recent years.In this review,we summarized the updated research of chemical constituents and biological activities of Polygonati Rhizoma,especially the metabolic regulation,immunomodulatory effects,and anti-fatigue activities,aiming to provide a comprehensive understanding,broaden the usage and promote more in-depth exploration of Polygonati Rhizoma as a functional food.展开更多
Previous studies on the mechanisms of peripheral nerve injury(PNI)have mainly focused on the pathophysiological changes within a single injury site.However,recent studies have indicated that within the central nervous...Previous studies on the mechanisms of peripheral nerve injury(PNI)have mainly focused on the pathophysiological changes within a single injury site.However,recent studies have indicated that within the central nervous system,PNI can lead to changes in both injury sites and target organs at the cellular and molecular levels.Therefore,the basic mechanisms of PNI have not been comprehensively understood.Although electrical stimulation was found to promote axonal regeneration and functional rehabilitation after PNI,as well as to alleviate neuropathic pain,the specific mechanisms of successful PNI treatment are unclear.We summarize and discuss the basic mechanisms of PNI and of treatment via electrical stimulation.After PNI,activity in the central nervous system(spinal cord)is altered,which can limit regeneration of the damaged nerve.For example,cell apoptosis and synaptic stripping in the anterior horn of the spinal cord can reduce the speed of nerve regeneration.The pathological changes in the posterior horn of the spinal cord can modulate sensory abnormalities after PNI.This can be observed in cases of ectopic discharge of the dorsal root ganglion leading to increased pain signal transmission.The injured site of the peripheral nerve is also an important factor affecting post-PNI repair.After PNI,the proximal end of the injured site sends out axial buds to innervate both the skin and muscle at the injury site.A slow speed of axon regeneration leads to low nerve regeneration.Therefore,it can take a long time for the proximal nerve to reinnervate the skin and muscle at the injured site.From the perspective of target organs,long-term denervation can cause atrophy of the corresponding skeletal muscle,which leads to abnormal sensory perception and hyperalgesia,and finally,the loss of target organ function.The mechanisms underlying the use of electrical stimulation to treat PNI include the inhibition of synaptic stripping,addressing the excessive excitability of the dorsal root ganglion,alleviating neuropathic pain,improving neurological function,and accelerating nerve regeneration.Electrical stimulation of target organs can reduce the atrophy of denervated skeletal muscle and promote the recovery of sensory function.Findings from the included studies confirm that after PNI,a series of physiological and pathological changes occur in the spinal cord,injury site,and target organs,leading to dysfunction.Electrical stimulation may address the pathophysiological changes mentioned above,thus promoting nerve regeneration and ameliorating dysfunction.展开更多
Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time ...Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time synchronization and information coordination in DIMA systems.However,inconsistency between processing resources and communication network destroys the time determinism benefiting from partitions and time-triggered mechanism.To ensure such time determinism and achieve guaranteed real-time performance,system design should collectively provide a global communication scheme for messages in network domain and a corresponding execution scheme for partitions in processing domain.This paper firstly establishes a general DIMA model which coordinates partitioned processing and time-triggered communication,and then proposes a hybrid scheduling algorithm using Mixed Integer Programming to produce feasible system schemes.Furthermore,incrementally integrating new functions causes upgrades or reconfigurations of DIMA systems and will generate integration cost.To control such cost,this paper further develops an optimization algorithm based on Maximum Satisfiability Problem and guarantees that the scheduling design for upgraded DIMA systems inherit their original schemes as much as possible.Finally,two typical cases,including a simple fully connected DIMA system case and an industrial DIMA system case,are constructed to illustrate our DIMA model and validate the effectiveness of our hybrid scheduling algorithms.展开更多
Although mesenchymal stem cell-derived exosomes(MSC-exos)have been shown to have therapeutic effects in experimental periodontitis,their drawbacks,such as low yield and limited efficacy,have hampered their clinical ap...Although mesenchymal stem cell-derived exosomes(MSC-exos)have been shown to have therapeutic effects in experimental periodontitis,their drawbacks,such as low yield and limited efficacy,have hampered their clinical application.These drawbacks can be largely reduced by replacing the traditional 2D culture system with a 3D system.However,the potential function of MSC-exos produced by 3D culture(3D-exos)in periodontitis remains elusive.This study showed that compared with MSC-exos generated via 2D culture(2D-exos),3D-exos showed enhanced anti-inflammatory effects in a ligature-induced model of periodontitis by restoring the reactive T helper 17(Th17)cell/Treg balance in inflamed periodontal tissues.Mechanistically,3D-exos exhibited greater enrichment of miR-1246,which can suppress the expression of Nfat5,a key factor that mediates Th17 cell polarization in a sequence-dependent manner.Furthermore,we found that recovery of the Th17 cell/Treg balance in the inflamed periodontium by the local injection of 3D-exos attenuated experimental colitis.Our study not only showed that by restoring the Th17 cell/Treg balance through the miR-1246/Nfat5 axis,the 3D culture system improved the function of MSC-exos in the treatment of periodontitis,but also it provided a basis for treating inflammatory bowel disease(IBD)by restoring immune responses in the inflamed periodontium.展开更多
It has been almost 50 years since the term“brain–computer interface”(BCI)was first proposed by Jacques J.Vidal in 1973[1].Unlike traditional electronic interfaces that transmit nonliving information between devices...It has been almost 50 years since the term“brain–computer interface”(BCI)was first proposed by Jacques J.Vidal in 1973[1].Unlike traditional electronic interfaces that transmit nonliving information between devices,BCIs set up a communication bridge between a living brain and nonliving devices.Technically speaking,a BCI is a system that measures brain activity and converts it into the artificial outputs that replace,restore,enhance,supplement,or improve the natural central nervous system outputs[2].At present,electroencephalography(EEG)is the most commonly used brain signal for BCIs.展开更多
Among multitudinous metal‐oxide catalysts for the selective catalytic reduction of NOx with NH3(NH3‐SCR),Mn‐based catalysts have become very popular and developed rapidly in recent years because of its superior low...Among multitudinous metal‐oxide catalysts for the selective catalytic reduction of NOx with NH3(NH3‐SCR),Mn‐based catalysts have become very popular and developed rapidly in recent years because of its superior low‐temperature denitrification activity,mainly originating from multi‐valence of Mn.Most studies suggest that the catalytic activity of multi‐component oxides is superior to that of single‐component catalysts owing to the synergistic effect among the metallic elements in such materials,of which more attentions have been given to Ce as an additive owing to its powerful oxygen storage capacity,redox ability and its ready availability.As the core of SCR technology,the research points in catalyst development at the present stage of all researchers in countries mainly centralize on the optimization of active components,carriers,calcination temperature,calcination time and temperature‐raising procedure,giving little thought to the effects of the calcination atmosphere.In the present work,Ce‐modified Mn‐based catalysts were prepared by a simple impregnation method.The effects of the calcination atmosphere(N2,air or O2)on the performance of the resulting materials during NH3‐SCR and its causes of the differences were subsequently investigated and characterized using various analytical methods.Data obtained from X‐ray diffraction,thermogravimetry and temperature‐programmed reduction with hydrogen show that calcination under N2reduces both the degree of oxidation and crystallization of the MnOx.Scanning electron microscopy also demonstrates that the use of N2inhibits the growth of grains and increases the dispersion of the catalysts.In addition,the results of temperature‐programmed desorption with ammonia indicate that catalysts calcined under N2exhibit a greater quantity of acid sites.Finally,X‐ray photoelectron spectrometry and activity results demonstrate that MnOx in the lower valence states is more favorable for NH3‐SCR reactions.In conclusion,catalysts calcined under N2show superior performance during NH3‐SCR for NOx removal,allowing NO conversions up to94%at473K.展开更多
High nitrate(NO_3^-)loading in water bodies is a crucial factor inducing the eutrophication of lakes.We tried to enhance NO_3^-reduction in overlying water by coupling sediment microbial fuel cells(SMFCs)with submerge...High nitrate(NO_3^-)loading in water bodies is a crucial factor inducing the eutrophication of lakes.We tried to enhance NO_3^-reduction in overlying water by coupling sediment microbial fuel cells(SMFCs)with submerged aquatic plant Ceratophyllum demersum.A comparative study was conducted by setting four treatments:open-circuit SMFC(Control),closed-circuit SMFC(SMFC-c),open-circuit SMFC with C.demersum(Plant),and closed-circuit SMFC with C.demersum(P-SMFC-c).The electrochemical parameters were documented to illustrate the bio-electrochemical characteristics of SMFC-c and P-SMFC-c.Removal pathways of NO_3^- in different treatments were studied by adding quantitative^(15)NO_3^- to water column.The results showed that the cathodic reaction in SMFC-c was mainly catalyzed by aerobic organisms attached on the cathode,including algae,Pseudomonas,Bacillus,and Albidiferax.The oxygen secreted by plants significantly improved the power generation of SMFC-c.Both electrogenesis and plants enhanced the complete removal of NO_3^- from the sediment–water system.The complete removal rates of added^(15)N increased by 17.6% and 10.2% for SMFC-c and plant,respectively,when compared with control at the end of experiment.The electrochemical/heterotrophic and aerobic denitrification on cathodes mainly drove the higher reduction of NO_3^- in SMFC-c and plant,respectively.The coexistence of electrogenesis and plants further increased the complete removal of NO_3^- with a rate of 23.1%.The heterotrophic and aerobic denitrifications were simultaneously promoted with a highest abundance of Flavobacterium,Bacillus,Geobacter,Pseudomonas,Rhodobacter,and Arenimonas on the cathode.展开更多
Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal ...Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal region for mediating the biological response to stress. Different stressors induce distinct alterations of neuronal activity in the CEA; however, few studies have reported the characteristics of CEA neuronal activity induced by RWIS. Therefore, we explored this issue using immunohistochemistry and in vivo extracellular single-unit recording. Our results showed that RWIS and restraint stress(RS) differentially changed the c-Fos expression and firing properties of neurons in the medial CEA. In addition,RWIS, but not RS, induced the activation of corticotropinreleasing hormone neurons in the CEA. These findings suggested that specific neuronal activation in the CEA is involved in the formation of RWIS-induced gastric ulcers.This study also provides a possible theoretical explanation for the different gastric dysfunctions induced by different stressors.展开更多
Electrocatalytic CO2 reduction(CO2 ER)into formate is a desirable route to achieve efficient transformation of CO2 to value-added chemicals,however,it still suffers from limited catalytic activity and poor selectivity...Electrocatalytic CO2 reduction(CO2 ER)into formate is a desirable route to achieve efficient transformation of CO2 to value-added chemicals,however,it still suffers from limited catalytic activity and poor selectivity.Herein,we develop a hybrid electrocatalyst composed of bismuth and bismuth oxide nanoparticles(NPs)supported on nitrogen-doped reduced graphene oxide(Bi/Bi2 O3/NrGO)nanosheets prepared by a combined hydrothermal with calcination treatment.Thanks to the combination of undercoordinated sites and strong synergistic effect between Bi and Bi2 O3,Bi/Bi2 O3/NrGO-700 hybrid displays a promoted CO2 ER catalytic performance and selectivity for formate production,as featured by a small onset potential of-0.5 V,a high current density of-18 mA/cm2,the maximum Faradaic efficiency of85%at-0.9 V,and a low Tafel slope of 166 mV/dec.Experimental results reveal that the higher CO2 ER performance of Bi/Bi2 O3/NrGO-700 than that of Bi NPs supported on NrGO(Bi/NrGO)can be due to the partial reduction of Bi2 O3 NPs into Bi,which significantly increases undercoordinated active sites on Bi NPs surface,thus boosting its CO2 ER performance.Furthermore,a two-electrode device with Ir/C anode and Bi/Bi2 O3/NrGO-700 cathode could be integrated with two alkaline batteries or a planar solar cell to achieve highly active water splitting and CO2 ER.展开更多
α‐,β‐,δ‐,andγ‐MnO2nanocrystals are successfully prepared.We then evaluated the NH3selective catalytic reduction(SCR)performance of the MnO2catalysts with different phases.The NOx conversion efficiency decrease...α‐,β‐,δ‐,andγ‐MnO2nanocrystals are successfully prepared.We then evaluated the NH3selective catalytic reduction(SCR)performance of the MnO2catalysts with different phases.The NOx conversion efficiency decreased in the order:γ‐MnO2>α‐MnO2>δ‐MnO2>β‐MnO2.The NOx conversion with the use ofγ‐MnO2andα‐MnO2catalysts reached90%in the temperature range of140–200°C,while that based onβ‐MnO2reached only40%at200°C.Theγ‐MnO2andα‐MnO2nanowire crystal morphologies enabled good dispersion of the catalysts and resulted in a relatively high specific surface area.We found thatγ‐MnO2andα‐MnO2possessed stronger reducing abilities and more and stronger acidic sites than the other catalysts.In addition,more chemisorbed oxygen existed on the surface of theγ‐MnO2andα‐MnO2catalysts.Theγ‐MnO2andα‐MnO2catalysts showed excellent performance in the low‐temperature SCR of NO to N2with NH3.展开更多
Phenolamide(PA)metabolites play important roles in the interaction between plants and pathogens.The putrescine hydroxycinnamoyl transferase genes Os PHT3 and Os PHT4 positively regulate rice cell death and resistance ...Phenolamide(PA)metabolites play important roles in the interaction between plants and pathogens.The putrescine hydroxycinnamoyl transferase genes Os PHT3 and Os PHT4 positively regulate rice cell death and resistance to Magnaporthe oryzae.The b ZIP transcription factor APIP5,a negative regulator of cell death and rice immunity,directly binds to the Os PHT4 promoter to regulate putrescine-derived PAs.Whether other hydroxycinnamoyl transferase(HT)genes also participate in APIP5-mediated immunity remains unclear.Surprisingly,we find that genes encoding agmatine hydroxycinnamoyl transferases Os AHT1 and Os AHT2,tryptamine hydroxycinnamoyl transferases Os TBT1 and Os TBT2,and tyramine hydroxycinnamoyl transferases Os THT1 and Os THT2,responsible for the biosynthesis of polyamine-derived PAs are all up-regulated in APIP5-RNAi transgenic plants compared with segregated wild-type rice.Furthermore,both Os AHT1/2 and Os TBT1/2 are induced during M.oryzae infection,showing expression patterns similar to those previously reported for Os THT1/2 and Os PHT3/4.Transgenic plants overexpressing either Os AHT2-GFP or Os TBT1-GFP show enhanced resistance against M.oryzae and accumulated more PA metabolites and lignin compared with wild-type plants.Interestingly,as demonstrated for Os PHT4,APIP5 directly binds to the promoters of Os AHT1/2,Os TBT1/2,and Os THT1/2,repressing their transcription.Together,these results indicate that the HT genes are common targets of APIP5 and that PAs play critical roles in rice immunity.展开更多
Atomically dispersed metal-nitrogen sites-anchored carbon materials have been developed as effective catalysts for CO2 electroreduction(CO2 ER),but they still suffer from the imprecisely control of type and coordinati...Atomically dispersed metal-nitrogen sites-anchored carbon materials have been developed as effective catalysts for CO2 electroreduction(CO2 ER),but they still suffer from the imprecisely control of type and coordination number of N atoms bonded with central metal.Herein,we develop a family of single metal atom bonded by N atoms anchored on carbons(SAs-M-N-C,M=Fe,Co,Ni,Cu)for CO2 ER,which composed of accurate pyrrole-type M-N4 structures with isolated metal atom coordinated by four pyrrolic N atoms.Benefitting from atomically coordinated environment and specific selectivity of M-N4 centers,SAs-Ni-N-C exhibits superior CO2 ER performance with onset potential of-0.3 V,CO Faradaic efficiency(F.E.) of 98.5%at-0.7 V,along with low Tafel slope of 115 mV dec-1 and superior stability of 50 h,exceeding all the previously reported M-N-C electrocatalysts for CO2-to-CO conversion.Experimental results manifest that the different intrinsic activities of M-N4 structures in SAs-M-N-C result in the corresponding sequence of Ni> Fe> Cu> Co for CO2 ER performance.An integrated Zn-CO2 battery with Zn foil and SAs-Ni-N-C is constructed to simultaneously achieve CO2-to-CO conversion and electric energy output,which delivers a peak power density of 1.4 mW cm-2 and maximum CO F.E.of 93.3%.展开更多
A numerical simulation study was performed to clarify the thermal mixing characteristics of coolant in the core bottom structure of the high-temperature gas-cooled reactor(HTR). The flow field and temperature field in...A numerical simulation study was performed to clarify the thermal mixing characteristics of coolant in the core bottom structure of the high-temperature gas-cooled reactor(HTR). The flow field and temperature field in the hot gas chamber and the hot gas duct of the HTR were obtained based on the commercial computational fluid dynamics(CFD) program. The numerical simulation results showed that the helium flow with different temperatures in the hot gas mixing chamber and the hot gas duct mixed intensively, and the mixing rate of the temperature in the outlet of the hot gas duct reached 98 %. The results indicated many large-scale swirling flow structures and strong turbulence in the hot gas mixing chamber and the entrance of the hot gas duct, which were responsible for the excellent thermal mixing of the hot gas chamber and the hot gas duct. The calculated results showed that the temperature mixing rate of the hot gas chamber decreased only marginally with increasing Reynolds number.展开更多
In this work,we investigated the discharge characteristics and heating mechanisms of argon helicon plasma in different wave coupled modes with and without blue core.Spatially resolved spectroscopy and emission intensi...In this work,we investigated the discharge characteristics and heating mechanisms of argon helicon plasma in different wave coupled modes with and without blue core.Spatially resolved spectroscopy and emission intensity of argon atom and ion lines were measured via local optical emission spectroscopy,and electron density was measured experimentally by an RFcompensated Langmuir probe.The relation between the emission intensity and the electron density was obtained and the wavenumbers of helicon and’Trivelpiece-Gould’(TG)waves were calculated by solving the dispersion relation in wave modes.The results show that at least two distinct wave coupled modes appear in argon helicon plasma at increasing RF power,i.e.blue core(or BC)mode with a significant bright core of blue lights and a normal wave(NW)mode without blue core.The emission intensity of atom line 750.5 nm(lArⅠ750.5nm)is related to the electron density and tends to be saturated in wave coupled modes due to the neutral depletion,while the intensity of ion line 480.6 nm(IArⅡ480.6nm)is a function of the electron density and temperature,and increases dramatically as the RF power is increased.Theoretical analysis shows that TG waves are strongly damped at the plasma edge in NW and/or BC modes,while helicon waves are the dominant mechanism of power deposition or central heating of electrons in both modes.The formation of BC column mainly depends on the enhanced central electron heating by helicon waves rather than TG waves since the excitation of TG waves would be suppressed in this special anti-resonance region.展开更多
The nonlinear phenomenon is very popular in dielectric barrier discharge （DBD） plasmas. There are at least three kinds of spatial and temporal nonlinear phenomena appearing synchronously or asynchronously in DBDs, i...The nonlinear phenomenon is very popular in dielectric barrier discharge （DBD） plasmas. There are at least three kinds of spatial and temporal nonlinear phenomena appearing synchronously or asynchronously in DBDs, i.e. self-organized patterns, striations and chaos. This paper describes the recent research and progress in understanding the nature of these nonlinear phenomena. Patterns are macroscopic structures with certain spatial and/or temporal periodicities generated through self- organization of microscopic parameters. The physics of patterns in DBDs is mainly associated with lateral dynamic behaviors or the lateral non-local effect of charged particles resulting in the lateral development or non-uniformity of discharge. Striations are ionization waves with unique properties determined by transport phenomena, ionization processes and electron kinetics in current-carrying plasmas. The physics of striations in DBDs is mainly associated with the advances in non-local electron kinetics in spatially inhomogeneous plasmas. Chaos is a kind of random and non-periodic phenomenon occunfng in a determined dynamic system, following a series of certain rules while exhibiting random locomotion, and is regarded as an intrinsic and ubiquitous phenomenon in a nonlinear dynamic system. An evolution trajectory including period-doubling bifurcation to chaos was observed in DBDs or DBD-derived plasmas. In a common sense, it is believed that the formation of all the three nonlinear phenomena in a DBD system should be related to the non-local transversal and/or longitudinal dynamics of space charges （i.e. non-local effect） or the localized electric field interaction. Future work is still needed on the underlying physics and should be directed to pursuing the unification of these nonlinear phenomena in DBD.展开更多
A 2D fluid model was employed to simulate the influence of dielectric on the propagation of atmospheric pressure helium plasma jet based on coplanar dielectric barrier discharge（DBD）.The spatio-temporal distribution...A 2D fluid model was employed to simulate the influence of dielectric on the propagation of atmospheric pressure helium plasma jet based on coplanar dielectric barrier discharge（DBD）.The spatio-temporal distributions of electron density,ionization rate,electrical field,spatial charge and the spatial structure were obtained for different dielectric tubes that limit the helium flow.The results show that the change of the relative permittivity of the dielectric tube where the plasma jet travels inside has no influence on the formation of DBD itself,but has great impact on the jet propagation.The velocity of the plasma jet changes drastically when the jet passes from a tube of higher permittivity to one of lower permittivity,resulting in an increase in jet length,ionization rate and electric field,as well as a change in the distribution of space charges and discharge states.The radius of the dielectric tube has a great influence on the ring-shaped or solid bullet structure.These results can well explain the behavior of the plasma jet from the dielectric tube into the ambient air and the hollow bullet in experiments.展开更多
[ Objective] The study aimed to discuss the temporal and spatial variation of phytoplankton community and main pollution indicators in cyanophyte enrichment area of northern Dianchi Lake. [ Method ] In the cyanophyte ...[ Objective] The study aimed to discuss the temporal and spatial variation of phytoplankton community and main pollution indicators in cyanophyte enrichment area of northern Dianchi Lake. [ Method ] In the cyanophyte enrichment area of northern Dianchi Lake, phytoplankton community, chlorophyll a, total nitrogen （TN） and total phosphorus （TP） concentration had been monitored monthly from January 2007 to December 2011, and the temporal and spatial variation of phytoplankton community and main pollution indicators were analyzed. [ Result] From January 2007 to December 2011, algal diversity in the area increased slightly, and algal diversity in the alongshore region was less than that in the offshore re- gion ; chlorophyll a, TN and TP concentration decreased in the alongshore region, but it was otherwise in the offshore region; chlorophyll a, TN and TP concentration in the alongshore region were higher than those in the offshore region. [ Conclusion] The research could provide theoretical references for the control of cyanophyte bloom and achievement evaluation of each control measure in Dianchi Lake.展开更多
Polycystic ovary syndrome (PCOS) is a highly familial and heritable endocrine disorder. Over half of the daughters born to women with PCOS may eventually develop their own PCOS-related symptoms. Progress in the treatm...Polycystic ovary syndrome (PCOS) is a highly familial and heritable endocrine disorder. Over half of the daughters born to women with PCOS may eventually develop their own PCOS-related symptoms. Progress in the treatment of PCOS is currently hindered by the complexity of its clinical manifestations and incomplete knowledge of its etiopathogenesis. Various animal models, including experimentally induced, naturally occurring, and spontaneously arising ones, have been established to emulate a wide range of phenotypical and pathological traits of human PCOS. These studies have led to a paradigm shift in understanding the genetic, developmental, and evolutionary origins of this disorder. Furthermore, emerging evidence suggests that animal models are useful in evaluating state-of-the-art drugs and treatments for PCOS. This review aims to provide a comprehensive summary of recent studies of PCOS in animal models, highlighting the power of these disease models in understanding the biology of PCOS and aiding high-throughput approaches.展开更多
It has been well documented that grain size plays a critical role in the strain hardening behaviors of metals and alloys.However,the influence of grain size on the strain hardening of high entropy alloys(HEAs)was not ...It has been well documented that grain size plays a critical role in the strain hardening behaviors of metals and alloys.However,the influence of grain size on the strain hardening of high entropy alloys(HEAs)was not fully understood.Here,we report that the grain size not only affects the twinning-induced plasticity(TWIP)effect but also changes the dislocation-based deformation behaviors of face-centeredcubic(fcc)HEAs significantly.The strain hardening and deformation micro-mechanisms of NiCoCrFe and Ni_(2)CoCrFe were investigated using electron channeling contrast(ECCI)analysis.Our results showed that Ni_(2)CoCrFe exhibits a typical three-stage strain hardening behavior and NiCoCrFe shows the fourth stage at high strains due to the TWIP effect.For both NiCoCrFe and Ni_(2)CoCrFe,the increase of grain size leads to a transition of dislocation glide from wavy to planar mode,resulting in a low value and the recovery of strain hardening rate in stage II.The large-grain NiCoCrFe showed a higher strain hardening rate in stage IV due to the promoted deformation twinning.Combining the strain hardening behaviors of the TWIPNiCoCrFe and the mechanically stable Ni_(2)CoCrFe,we showed that the grain size influences the stage II hardening through tuning dislocation glide mode and the stage IV by tailoring deformation twinning activity of the Ni-Co-Cr-Fe HEAs.The grain size just affects stages I and III slightly in the current cases.These findings will also provide some insights into the understanding of strain hardening behaviors in other face-centered-cubic HEAs.展开更多
基金funded by Scientific and Technological Research Project and Technology Innovation Platform Project of Huibei Provincial Department of Science and Technology(2025AFD345 and 2024CSA071)grant from Huanggang Science and Technology Bureau(ZDZX20240008)。
文摘Polygonati Rhizoma,a functional food and a traditional Chinese medicine broadly used in China and several Southeast Asia countries,possesses effective health-promoting activities.Prepared from 3 plants in Polygonatum genus(Polygonatum kingianum,Polygonatum sibiricum,and Polygonatum cyrtonema),Polygonati Rhizoma has drawn increasing attention due to its remarkable immune-enhancing and metabolic regulatory activities in recent years.In this review,we summarized the updated research of chemical constituents and biological activities of Polygonati Rhizoma,especially the metabolic regulation,immunomodulatory effects,and anti-fatigue activities,aiming to provide a comprehensive understanding,broaden the usage and promote more in-depth exploration of Polygonati Rhizoma as a functional food.
基金supported by the National Natural Science Foundation of China,No.81801787(to XZS)China Postdoctoral Science Foundation,No.2018M640238(to XZS)the Natural Science Foundation of Tianjin,No.20JCQNJC01690(XLC).
文摘Previous studies on the mechanisms of peripheral nerve injury(PNI)have mainly focused on the pathophysiological changes within a single injury site.However,recent studies have indicated that within the central nervous system,PNI can lead to changes in both injury sites and target organs at the cellular and molecular levels.Therefore,the basic mechanisms of PNI have not been comprehensively understood.Although electrical stimulation was found to promote axonal regeneration and functional rehabilitation after PNI,as well as to alleviate neuropathic pain,the specific mechanisms of successful PNI treatment are unclear.We summarize and discuss the basic mechanisms of PNI and of treatment via electrical stimulation.After PNI,activity in the central nervous system(spinal cord)is altered,which can limit regeneration of the damaged nerve.For example,cell apoptosis and synaptic stripping in the anterior horn of the spinal cord can reduce the speed of nerve regeneration.The pathological changes in the posterior horn of the spinal cord can modulate sensory abnormalities after PNI.This can be observed in cases of ectopic discharge of the dorsal root ganglion leading to increased pain signal transmission.The injured site of the peripheral nerve is also an important factor affecting post-PNI repair.After PNI,the proximal end of the injured site sends out axial buds to innervate both the skin and muscle at the injury site.A slow speed of axon regeneration leads to low nerve regeneration.Therefore,it can take a long time for the proximal nerve to reinnervate the skin and muscle at the injured site.From the perspective of target organs,long-term denervation can cause atrophy of the corresponding skeletal muscle,which leads to abnormal sensory perception and hyperalgesia,and finally,the loss of target organ function.The mechanisms underlying the use of electrical stimulation to treat PNI include the inhibition of synaptic stripping,addressing the excessive excitability of the dorsal root ganglion,alleviating neuropathic pain,improving neurological function,and accelerating nerve regeneration.Electrical stimulation of target organs can reduce the atrophy of denervated skeletal muscle and promote the recovery of sensory function.Findings from the included studies confirm that after PNI,a series of physiological and pathological changes occur in the spinal cord,injury site,and target organs,leading to dysfunction.Electrical stimulation may address the pathophysiological changes mentioned above,thus promoting nerve regeneration and ameliorating dysfunction.
基金co-supported by the National Natural Science Foundation of China(No.71701020)the Defense Research Field Foundation of China(No.61403120404)the Civil Aircraft Airworthiness and Maintenance Key Laboratory Fund of Civil Aviation University of China(No.2017SW02).
文摘Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time synchronization and information coordination in DIMA systems.However,inconsistency between processing resources and communication network destroys the time determinism benefiting from partitions and time-triggered mechanism.To ensure such time determinism and achieve guaranteed real-time performance,system design should collectively provide a global communication scheme for messages in network domain and a corresponding execution scheme for partitions in processing domain.This paper firstly establishes a general DIMA model which coordinates partitioned processing and time-triggered communication,and then proposes a hybrid scheduling algorithm using Mixed Integer Programming to produce feasible system schemes.Furthermore,incrementally integrating new functions causes upgrades or reconfigurations of DIMA systems and will generate integration cost.To control such cost,this paper further develops an optimization algorithm based on Maximum Satisfiability Problem and guarantees that the scheduling design for upgraded DIMA systems inherit their original schemes as much as possible.Finally,two typical cases,including a simple fully connected DIMA system case and an industrial DIMA system case,are constructed to illustrate our DIMA model and validate the effectiveness of our hybrid scheduling algorithms.
基金This work was supported by grants from the National Natural Science Foundation of China(Grant Nos.81873713,81700959 and 81873829)the International Cooperation Project of Science and Technology in Guangdong Province(Grant No.2016B050502008)the Natural Science Foundation of the Tibet Autonomous Region(XZ2019ZR-ZY64(Z)).
文摘Although mesenchymal stem cell-derived exosomes(MSC-exos)have been shown to have therapeutic effects in experimental periodontitis,their drawbacks,such as low yield and limited efficacy,have hampered their clinical application.These drawbacks can be largely reduced by replacing the traditional 2D culture system with a 3D system.However,the potential function of MSC-exos produced by 3D culture(3D-exos)in periodontitis remains elusive.This study showed that compared with MSC-exos generated via 2D culture(2D-exos),3D-exos showed enhanced anti-inflammatory effects in a ligature-induced model of periodontitis by restoring the reactive T helper 17(Th17)cell/Treg balance in inflamed periodontal tissues.Mechanistically,3D-exos exhibited greater enrichment of miR-1246,which can suppress the expression of Nfat5,a key factor that mediates Th17 cell polarization in a sequence-dependent manner.Furthermore,we found that recovery of the Th17 cell/Treg balance in the inflamed periodontium by the local injection of 3D-exos attenuated experimental colitis.Our study not only showed that by restoring the Th17 cell/Treg balance through the miR-1246/Nfat5 axis,the 3D culture system improved the function of MSC-exos in the treatment of periodontitis,but also it provided a basis for treating inflammatory bowel disease(IBD)by restoring immune responses in the inflamed periodontium.
基金We appreciate the financial support from the National Key Research and Development Program of China(2017YFB1300300)the National Natural Science Foundation of China(62122059,81925020,61976152,and 81630051)the Young Elite Scientist Sponsorship Program by CAST(2018QNRC001).
文摘It has been almost 50 years since the term“brain–computer interface”(BCI)was first proposed by Jacques J.Vidal in 1973[1].Unlike traditional electronic interfaces that transmit nonliving information between devices,BCIs set up a communication bridge between a living brain and nonliving devices.Technically speaking,a BCI is a system that measures brain activity and converts it into the artificial outputs that replace,restore,enhance,supplement,or improve the natural central nervous system outputs[2].At present,electroencephalography(EEG)is the most commonly used brain signal for BCIs.
文摘Among multitudinous metal‐oxide catalysts for the selective catalytic reduction of NOx with NH3(NH3‐SCR),Mn‐based catalysts have become very popular and developed rapidly in recent years because of its superior low‐temperature denitrification activity,mainly originating from multi‐valence of Mn.Most studies suggest that the catalytic activity of multi‐component oxides is superior to that of single‐component catalysts owing to the synergistic effect among the metallic elements in such materials,of which more attentions have been given to Ce as an additive owing to its powerful oxygen storage capacity,redox ability and its ready availability.As the core of SCR technology,the research points in catalyst development at the present stage of all researchers in countries mainly centralize on the optimization of active components,carriers,calcination temperature,calcination time and temperature‐raising procedure,giving little thought to the effects of the calcination atmosphere.In the present work,Ce‐modified Mn‐based catalysts were prepared by a simple impregnation method.The effects of the calcination atmosphere(N2,air or O2)on the performance of the resulting materials during NH3‐SCR and its causes of the differences were subsequently investigated and characterized using various analytical methods.Data obtained from X‐ray diffraction,thermogravimetry and temperature‐programmed reduction with hydrogen show that calcination under N2reduces both the degree of oxidation and crystallization of the MnOx.Scanning electron microscopy also demonstrates that the use of N2inhibits the growth of grains and increases the dispersion of the catalysts.In addition,the results of temperature‐programmed desorption with ammonia indicate that catalysts calcined under N2exhibit a greater quantity of acid sites.Finally,X‐ray photoelectron spectrometry and activity results demonstrate that MnOx in the lower valence states is more favorable for NH3‐SCR reactions.In conclusion,catalysts calcined under N2show superior performance during NH3‐SCR for NOx removal,allowing NO conversions up to94%at473K.
基金supported by the National Key Research and Development Plan of China (No. 2016YFC0500403-03)the Science and Technology Service Network Initiative of the Chinese Academy of Sciences (No. KFJ-STS-ZDTP-038)
文摘High nitrate(NO_3^-)loading in water bodies is a crucial factor inducing the eutrophication of lakes.We tried to enhance NO_3^-reduction in overlying water by coupling sediment microbial fuel cells(SMFCs)with submerged aquatic plant Ceratophyllum demersum.A comparative study was conducted by setting four treatments:open-circuit SMFC(Control),closed-circuit SMFC(SMFC-c),open-circuit SMFC with C.demersum(Plant),and closed-circuit SMFC with C.demersum(P-SMFC-c).The electrochemical parameters were documented to illustrate the bio-electrochemical characteristics of SMFC-c and P-SMFC-c.Removal pathways of NO_3^- in different treatments were studied by adding quantitative^(15)NO_3^- to water column.The results showed that the cathodic reaction in SMFC-c was mainly catalyzed by aerobic organisms attached on the cathode,including algae,Pseudomonas,Bacillus,and Albidiferax.The oxygen secreted by plants significantly improved the power generation of SMFC-c.Both electrogenesis and plants enhanced the complete removal of NO_3^- from the sediment–water system.The complete removal rates of added^(15)N increased by 17.6% and 10.2% for SMFC-c and plant,respectively,when compared with control at the end of experiment.The electrochemical/heterotrophic and aerobic denitrification on cathodes mainly drove the higher reduction of NO_3^- in SMFC-c and plant,respectively.The coexistence of electrogenesis and plants further increased the complete removal of NO_3^- with a rate of 23.1%.The heterotrophic and aerobic denitrifications were simultaneously promoted with a highest abundance of Flavobacterium,Bacillus,Geobacter,Pseudomonas,Rhodobacter,and Arenimonas on the cathode.
基金supported by the National Natural Science Foundation of China (31571104 and 81501149)the Science and Technological Project of Shandong Province of China (2016GSF201058)
文摘Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal region for mediating the biological response to stress. Different stressors induce distinct alterations of neuronal activity in the CEA; however, few studies have reported the characteristics of CEA neuronal activity induced by RWIS. Therefore, we explored this issue using immunohistochemistry and in vivo extracellular single-unit recording. Our results showed that RWIS and restraint stress(RS) differentially changed the c-Fos expression and firing properties of neurons in the medial CEA. In addition,RWIS, but not RS, induced the activation of corticotropinreleasing hormone neurons in the CEA. These findings suggested that specific neuronal activation in the CEA is involved in the formation of RWIS-induced gastric ulcers.This study also provides a possible theoretical explanation for the different gastric dysfunctions induced by different stressors.
基金support of the Natural Science Foundation of Zhejiang Province(No.LR16E080003)support of National Natural Science Foundation of China(Nos.21922811,51702284,21878270)+2 种基金Zhejiang Provincial Natural Science Foundation of China(No.LR19B060002)the Fundamental Research Funds for the Central Universitiesthe Startup Foundation for Hundred-Talent Program of Zhejiang University。
文摘Electrocatalytic CO2 reduction(CO2 ER)into formate is a desirable route to achieve efficient transformation of CO2 to value-added chemicals,however,it still suffers from limited catalytic activity and poor selectivity.Herein,we develop a hybrid electrocatalyst composed of bismuth and bismuth oxide nanoparticles(NPs)supported on nitrogen-doped reduced graphene oxide(Bi/Bi2 O3/NrGO)nanosheets prepared by a combined hydrothermal with calcination treatment.Thanks to the combination of undercoordinated sites and strong synergistic effect between Bi and Bi2 O3,Bi/Bi2 O3/NrGO-700 hybrid displays a promoted CO2 ER catalytic performance and selectivity for formate production,as featured by a small onset potential of-0.5 V,a high current density of-18 mA/cm2,the maximum Faradaic efficiency of85%at-0.9 V,and a low Tafel slope of 166 mV/dec.Experimental results reveal that the higher CO2 ER performance of Bi/Bi2 O3/NrGO-700 than that of Bi NPs supported on NrGO(Bi/NrGO)can be due to the partial reduction of Bi2 O3 NPs into Bi,which significantly increases undercoordinated active sites on Bi NPs surface,thus boosting its CO2 ER performance.Furthermore,a two-electrode device with Ir/C anode and Bi/Bi2 O3/NrGO-700 cathode could be integrated with two alkaline batteries or a planar solar cell to achieve highly active water splitting and CO2 ER.
基金supported by the National Natural Science Foundation of China(51502221)~~
文摘α‐,β‐,δ‐,andγ‐MnO2nanocrystals are successfully prepared.We then evaluated the NH3selective catalytic reduction(SCR)performance of the MnO2catalysts with different phases.The NOx conversion efficiency decreased in the order:γ‐MnO2>α‐MnO2>δ‐MnO2>β‐MnO2.The NOx conversion with the use ofγ‐MnO2andα‐MnO2catalysts reached90%in the temperature range of140–200°C,while that based onβ‐MnO2reached only40%at200°C.Theγ‐MnO2andα‐MnO2nanowire crystal morphologies enabled good dispersion of the catalysts and resulted in a relatively high specific surface area.We found thatγ‐MnO2andα‐MnO2possessed stronger reducing abilities and more and stronger acidic sites than the other catalysts.In addition,more chemisorbed oxygen existed on the surface of theγ‐MnO2andα‐MnO2catalysts.Theγ‐MnO2andα‐MnO2catalysts showed excellent performance in the low‐temperature SCR of NO to N2with NH3.
基金supported by grants from the National Natural Science Foundation of China (32161143009, 31822041 and 31972225) to Y.N.the National Natural Science Foundation of China (U20A2021) to R.W.the National Natural Science Foundation of China (31801692) to F.Z
文摘Phenolamide(PA)metabolites play important roles in the interaction between plants and pathogens.The putrescine hydroxycinnamoyl transferase genes Os PHT3 and Os PHT4 positively regulate rice cell death and resistance to Magnaporthe oryzae.The b ZIP transcription factor APIP5,a negative regulator of cell death and rice immunity,directly binds to the Os PHT4 promoter to regulate putrescine-derived PAs.Whether other hydroxycinnamoyl transferase(HT)genes also participate in APIP5-mediated immunity remains unclear.Surprisingly,we find that genes encoding agmatine hydroxycinnamoyl transferases Os AHT1 and Os AHT2,tryptamine hydroxycinnamoyl transferases Os TBT1 and Os TBT2,and tyramine hydroxycinnamoyl transferases Os THT1 and Os THT2,responsible for the biosynthesis of polyamine-derived PAs are all up-regulated in APIP5-RNAi transgenic plants compared with segregated wild-type rice.Furthermore,both Os AHT1/2 and Os TBT1/2 are induced during M.oryzae infection,showing expression patterns similar to those previously reported for Os THT1/2 and Os PHT3/4.Transgenic plants overexpressing either Os AHT2-GFP or Os TBT1-GFP show enhanced resistance against M.oryzae and accumulated more PA metabolites and lignin compared with wild-type plants.Interestingly,as demonstrated for Os PHT4,APIP5 directly binds to the promoters of Os AHT1/2,Os TBT1/2,and Os THT1/2,repressing their transcription.Together,these results indicate that the HT genes are common targets of APIP5 and that PAs play critical roles in rice immunity.
基金financial support from Zhejiang Province Basic Public Welfare Research Project(LGF19B070006)financial supports from National Natural Science Foundation of China(21922811,21878270,51702284,21961160742)+2 种基金Zhejiang Provincial Natural Science Foundation of China(LR19B060002)supported by the Fundamental Research Funds for the Central Universitiesthe Startup Foundation for Hundred-Talent Program of Zhejiang University.
文摘Atomically dispersed metal-nitrogen sites-anchored carbon materials have been developed as effective catalysts for CO2 electroreduction(CO2 ER),but they still suffer from the imprecisely control of type and coordination number of N atoms bonded with central metal.Herein,we develop a family of single metal atom bonded by N atoms anchored on carbons(SAs-M-N-C,M=Fe,Co,Ni,Cu)for CO2 ER,which composed of accurate pyrrole-type M-N4 structures with isolated metal atom coordinated by four pyrrolic N atoms.Benefitting from atomically coordinated environment and specific selectivity of M-N4 centers,SAs-Ni-N-C exhibits superior CO2 ER performance with onset potential of-0.3 V,CO Faradaic efficiency(F.E.) of 98.5%at-0.7 V,along with low Tafel slope of 115 mV dec-1 and superior stability of 50 h,exceeding all the previously reported M-N-C electrocatalysts for CO2-to-CO conversion.Experimental results manifest that the different intrinsic activities of M-N4 structures in SAs-M-N-C result in the corresponding sequence of Ni> Fe> Cu> Co for CO2 ER performance.An integrated Zn-CO2 battery with Zn foil and SAs-Ni-N-C is constructed to simultaneously achieve CO2-to-CO conversion and electric energy output,which delivers a peak power density of 1.4 mW cm-2 and maximum CO F.E.of 93.3%.
基金Supported by National Natural Science Foundation of China (No. 11375099)
文摘A numerical simulation study was performed to clarify the thermal mixing characteristics of coolant in the core bottom structure of the high-temperature gas-cooled reactor(HTR). The flow field and temperature field in the hot gas chamber and the hot gas duct of the HTR were obtained based on the commercial computational fluid dynamics(CFD) program. The numerical simulation results showed that the helium flow with different temperatures in the hot gas mixing chamber and the hot gas duct mixed intensively, and the mixing rate of the temperature in the outlet of the hot gas duct reached 98 %. The results indicated many large-scale swirling flow structures and strong turbulence in the hot gas mixing chamber and the entrance of the hot gas duct, which were responsible for the excellent thermal mixing of the hot gas chamber and the hot gas duct. The calculated results showed that the temperature mixing rate of the hot gas chamber decreased only marginally with increasing Reynolds number.
基金National Natural Science Foundation of China(No.11975047)。
文摘In this work,we investigated the discharge characteristics and heating mechanisms of argon helicon plasma in different wave coupled modes with and without blue core.Spatially resolved spectroscopy and emission intensity of argon atom and ion lines were measured via local optical emission spectroscopy,and electron density was measured experimentally by an RFcompensated Langmuir probe.The relation between the emission intensity and the electron density was obtained and the wavenumbers of helicon and’Trivelpiece-Gould’(TG)waves were calculated by solving the dispersion relation in wave modes.The results show that at least two distinct wave coupled modes appear in argon helicon plasma at increasing RF power,i.e.blue core(or BC)mode with a significant bright core of blue lights and a normal wave(NW)mode without blue core.The emission intensity of atom line 750.5 nm(lArⅠ750.5nm)is related to the electron density and tends to be saturated in wave coupled modes due to the neutral depletion,while the intensity of ion line 480.6 nm(IArⅡ480.6nm)is a function of the electron density and temperature,and increases dramatically as the RF power is increased.Theoretical analysis shows that TG waves are strongly damped at the plasma edge in NW and/or BC modes,while helicon waves are the dominant mechanism of power deposition or central heating of electrons in both modes.The formation of BC column mainly depends on the enhanced central electron heating by helicon waves rather than TG waves since the excitation of TG waves would be suppressed in this special anti-resonance region.
基金National Natural Science Foundation of China for continuous financial support under Grant Nos. 10475007, 10875010, 11175017 and 51607074the State Education Ministry of China under Grant No. NCET-05-0176
文摘The nonlinear phenomenon is very popular in dielectric barrier discharge （DBD） plasmas. There are at least three kinds of spatial and temporal nonlinear phenomena appearing synchronously or asynchronously in DBDs, i.e. self-organized patterns, striations and chaos. This paper describes the recent research and progress in understanding the nature of these nonlinear phenomena. Patterns are macroscopic structures with certain spatial and/or temporal periodicities generated through self- organization of microscopic parameters. The physics of patterns in DBDs is mainly associated with lateral dynamic behaviors or the lateral non-local effect of charged particles resulting in the lateral development or non-uniformity of discharge. Striations are ionization waves with unique properties determined by transport phenomena, ionization processes and electron kinetics in current-carrying plasmas. The physics of striations in DBDs is mainly associated with the advances in non-local electron kinetics in spatially inhomogeneous plasmas. Chaos is a kind of random and non-periodic phenomenon occunfng in a determined dynamic system, following a series of certain rules while exhibiting random locomotion, and is regarded as an intrinsic and ubiquitous phenomenon in a nonlinear dynamic system. An evolution trajectory including period-doubling bifurcation to chaos was observed in DBDs or DBD-derived plasmas. In a common sense, it is believed that the formation of all the three nonlinear phenomena in a DBD system should be related to the non-local transversal and/or longitudinal dynamics of space charges （i.e. non-local effect） or the localized electric field interaction. Future work is still needed on the underlying physics and should be directed to pursuing the unification of these nonlinear phenomena in DBD.
文摘A 2D fluid model was employed to simulate the influence of dielectric on the propagation of atmospheric pressure helium plasma jet based on coplanar dielectric barrier discharge（DBD）.The spatio-temporal distributions of electron density,ionization rate,electrical field,spatial charge and the spatial structure were obtained for different dielectric tubes that limit the helium flow.The results show that the change of the relative permittivity of the dielectric tube where the plasma jet travels inside has no influence on the formation of DBD itself,but has great impact on the jet propagation.The velocity of the plasma jet changes drastically when the jet passes from a tube of higher permittivity to one of lower permittivity,resulting in an increase in jet length,ionization rate and electric field,as well as a change in the distribution of space charges and discharge states.The radius of the dielectric tube has a great influence on the ring-shaped or solid bullet structure.These results can well explain the behavior of the plasma jet from the dielectric tube into the ambient air and the hollow bullet in experiments.
基金Supported by the National Science and Technology Project of Water Pollution Control and Management (2009ZX07317-006-003)
文摘[ Objective] The study aimed to discuss the temporal and spatial variation of phytoplankton community and main pollution indicators in cyanophyte enrichment area of northern Dianchi Lake. [ Method ] In the cyanophyte enrichment area of northern Dianchi Lake, phytoplankton community, chlorophyll a, total nitrogen （TN） and total phosphorus （TP） concentration had been monitored monthly from January 2007 to December 2011, and the temporal and spatial variation of phytoplankton community and main pollution indicators were analyzed. [ Result] From January 2007 to December 2011, algal diversity in the area increased slightly, and algal diversity in the alongshore region was less than that in the offshore re- gion ; chlorophyll a, TN and TP concentration decreased in the alongshore region, but it was otherwise in the offshore region; chlorophyll a, TN and TP concentration in the alongshore region were higher than those in the offshore region. [ Conclusion] The research could provide theoretical references for the control of cyanophyte bloom and achievement evaluation of each control measure in Dianchi Lake.
基金supported in part by the National Key R&D Program of China(2021YFC2700403 and 2018YFA0800102)the National Natural Science Foundation of China(31871249 and 31871452).
文摘Polycystic ovary syndrome (PCOS) is a highly familial and heritable endocrine disorder. Over half of the daughters born to women with PCOS may eventually develop their own PCOS-related symptoms. Progress in the treatment of PCOS is currently hindered by the complexity of its clinical manifestations and incomplete knowledge of its etiopathogenesis. Various animal models, including experimentally induced, naturally occurring, and spontaneously arising ones, have been established to emulate a wide range of phenotypical and pathological traits of human PCOS. These studies have led to a paradigm shift in understanding the genetic, developmental, and evolutionary origins of this disorder. Furthermore, emerging evidence suggests that animal models are useful in evaluating state-of-the-art drugs and treatments for PCOS. This review aims to provide a comprehensive summary of recent studies of PCOS in animal models, highlighting the power of these disease models in understanding the biology of PCOS and aiding high-throughput approaches.
基金financial support from the National Natural Science Foundation of China(No.52001266)。
文摘It has been well documented that grain size plays a critical role in the strain hardening behaviors of metals and alloys.However,the influence of grain size on the strain hardening of high entropy alloys(HEAs)was not fully understood.Here,we report that the grain size not only affects the twinning-induced plasticity(TWIP)effect but also changes the dislocation-based deformation behaviors of face-centeredcubic(fcc)HEAs significantly.The strain hardening and deformation micro-mechanisms of NiCoCrFe and Ni_(2)CoCrFe were investigated using electron channeling contrast(ECCI)analysis.Our results showed that Ni_(2)CoCrFe exhibits a typical three-stage strain hardening behavior and NiCoCrFe shows the fourth stage at high strains due to the TWIP effect.For both NiCoCrFe and Ni_(2)CoCrFe,the increase of grain size leads to a transition of dislocation glide from wavy to planar mode,resulting in a low value and the recovery of strain hardening rate in stage II.The large-grain NiCoCrFe showed a higher strain hardening rate in stage IV due to the promoted deformation twinning.Combining the strain hardening behaviors of the TWIPNiCoCrFe and the mechanically stable Ni_(2)CoCrFe,we showed that the grain size influences the stage II hardening through tuning dislocation glide mode and the stage IV by tailoring deformation twinning activity of the Ni-Co-Cr-Fe HEAs.The grain size just affects stages I and III slightly in the current cases.These findings will also provide some insights into the understanding of strain hardening behaviors in other face-centered-cubic HEAs.
