Bisphenol A dicyanate ester resins modified by fluorine-containing liquid crystal compound(LCFE)are applied as polymer matrix(LCFE-BADCy),poly(p-phenylene-2,6-benzobisoxazole)(PBO)fibers as rein-forcements,and fluorin...Bisphenol A dicyanate ester resins modified by fluorine-containing liquid crystal compound(LCFE)are applied as polymer matrix(LCFE-BADCy),poly(p-phenylene-2,6-benzobisoxazole)(PBO)fibers as rein-forcements,and fluorine/adamantane PBO precursor(pre FABPBO)as interfacial compatibilizer to prepare the corresponding PBO fibers/FABPBO/LCFE-BADCy wave-transparent laminated composites.LCFE could improve the order degree of BADCy cured network,in favor of enhancing the wave-transparent perfor-mance,mechanical properties,and intrinsic thermal conductivity.The dielectric constant and dielectric loss of PBO fibers/FABPBO/LCFE-BADCy composites are highly temperature(25–200℃)and frequency(10^(4)–10^(7) Hz and 8.2–12.4 GHz)stable with the value of 2.49 and 0.003 under 10^(6) Hz at 25℃,and the corresponding wave transmission efficiency is 95.0%,higher than that of 92.5%for PBO fibers/BADCy com-posites.The interlamellar shear strength and flexural strength are respectively 50.7 MPa and 682.5 MPa,38.1%and 16.2%higher than those of PBO fibers/BADCy composites.Besides,the volume resistivity,breakdown voltage,heat resistance index,glass transition temperature,flame retardant grade,and ul-timate oxygen index of PBO fibers/FABPBO/LCFE-BADCy composites are respectively 5.3×10^(15)Ωcm,29.75 kV/mm,217.2℃,245.7℃,V-1 grade,and 33.6%,expected to be performed as a new generation of“lightweight/loading/wave-transparent”electromagnetic window materials in advanced military weapons and civil communication base station.展开更多
Advertisement calls play an important role in influencing female mate choice and are regarded as one of the key characters responsible for reproductive isolation and speciation events in frogs and toads. The black-spi...Advertisement calls play an important role in influencing female mate choice and are regarded as one of the key characters responsible for reproductive isolation and speciation events in frogs and toads. The black-spined toad, Bufo melanostictus, is one of the most common amphibians in Southeast Asia and is frequently observed in human habitations throughout its distributional range. The advertisement calls of the toad have not been well described. Here, we report the advertisement calls of this species from Lishui, Zhejiang, China during its breeding season. The advertisement calls of B. melanostictus are composed of single notes with a single harmonic frequency emitted sporadically. The call parameters recorded in this study were highly variable across recording times and with different body sizes. Dominant frequency was negatively correlated with body size. Comparing the calls of the B. melanostictus population from Lishui with the populations from five other localities(Bangkok, Thailand; Coorg, India; Burma, Myanmar; Bali, Indonesia; Halimun-Salak National Park, Indonesia), we found that call structure was similar among five different populations with no harmonics, while the Halimun-Salak National Park population contained two clear harmonics. Dominant frequency was similar between Bali(1.56 kHz) and Coorg(1.6 kHz) populations, while it was highly variable among other populations. Besides call duration, call interval and pulse/call rate may also be significantly different among the comparing populations. Pooling the available data, we observed some similarities and differences in call parameters among the six populations.展开更多
A data identifier(DID)is an essential tag or label in all kinds of databases—particularly those related to integrated computational materials engineering(ICME),inheritable integrated intelligent manufacturing(I3M),an...A data identifier(DID)is an essential tag or label in all kinds of databases—particularly those related to integrated computational materials engineering(ICME),inheritable integrated intelligent manufacturing(I3M),and the Industrial Internet ofThings.With the guidance and quick acceleration of the developme nt of advanced materials,as envisioned by official documents worldwide,more investigations are required to construct relative numerical standards for material informatics.This work proposes a universal DID format consisting of a set of build chains,which aligns with the classical form of identifier in both international and national standards,such as ISO/IEC 29168-1:2000,GB/T 27766-2011,GA/T 543.2-2011,GM/T 0006-2012,GJB 7365-2011,SL 325-2014,SL 607-201&WS 363.2-2011,and QX/T 39-2005.Each build chain is made up of capital letters and numbers,with no symbols.Moreover,the total length of each build chain is not restricted,which follows the formation of the Universal Coded Character Set in the international standard of ISO/IEC 10646.Based on these rules,the proposed DID is flexible and convenient for extendi ng and sharing in and between various cloud-based platforms.Accordingly,classical two-dimensional(2D)codes,including the Hanxin Code,Lots Perception Matrix(LP)Code,Quick Response(Q.R)code,Grid Matrix(GM)code,and Data Matrix(DM)Code,can be constructed and precisely recognized and/or decoded by either smart phones or specific machines.By utilizing these 2D codes as the fingerprints of a set of data linked with cloud-based platforms,progress and updates in the composition-processing-structure-property-performance workflow process can be tracked spontaneously,paving a path to accelerate the discovery and manufacture of advanced materials and enhance research productivity,performance,and collaboration.展开更多
Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was construct...Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was constructed to detect QTL for thousand-grain weight(TGW),grain length(GL)and grain width(GW)across eight environments.Genomic regions associated with grain size and grain weight were identified on chromosomes 4A and 6A using bulked segregant exome sequencing(BSE-Seq)analysis.After constructing genetic maps,six major QTL detected in at least four individual environments and in best linear unbiased estimator(BLUE)datasets,explained 7.50%-23.45%of the phenotypic variation.Except for QGl.cib-4A,the other five QTL were co-located in two regions,namely QTgw/Gw.cib-4A and QTgw/Gw/Gl.cib-6A.Interactions of these QTL were analyzed.Unlike QTgw/Gw/Gl.cib-6A,QTgw/Gw.cib-4A and QGl.cib-4A had no effect on grain number per spike(GNS).The QTL were validated in a second cross using Kompetitive Allele Specific PCR(KASP)markers.Since QTgw/Gw.cib-4A was probably a novel locus,it and the KASP markers reported here can be used in wheat breeding.TraesCS4A03G0191200 was predicted to be potential candidate gene for QTgw/Gw.cib-4A based on the sequence differences,spatiotemporal expression patterns,gene annotation and haplotype analysis.Our findings will be useful for fine mapping and for marker-assisted selection in wheat grain yield improvement.展开更多
Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(...Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(RIL)population derived from a cross between W7268 and Chuanyu 12(CY12)was employed to detect quantitative trait loci(QTLs)for thousand-grain weight(TGW),grain length(GL),grain width(GW),and the ratio of grain length to width(GLW)in six environments.Seven major QTLs,QGl.cib-2D,QGw.cib-2D,QGw.cib-3B,QGw.cib-4B.1,QGlw.cib-2D.1,QTgw.cib-2D.1 and QTgw.cib-3B.1,were consistently identified in at least four environments and the best linear unbiased estimation(BLUE)datasets,and they explained 2.61 to 34.85%of the phenotypic variance.Significant interactions were detected between the two major TGW QTLs and three major GW loci.In addition,QTgw.cib-3B.1 and QGw.cib-3B were co-located,and the improved TGW at this locus was contributed by GW.Unlike other loci,QTgw.cib-3B.1/QGw.cib-3B had no effect on grain number per spike(GNS).They were further validated in advanced lines using Kompetitive Allele Specific PCR(KASP)markers,and a comparison analysis indicated that QTgw.cib-3B.1/QGw.cib-3B is likely a novel locus.Six haplotypes were identified in the region of this QTL and their distribution frequencies varied between the landraces and cultivars.According to gene annotation,spatial expression patterns,ortholog analysis and sequence variation,the candidate gene of QTgw.cib-3B.1/QGw.cib-3B was predicted.Collectively,the major QTLs and KASP markers reported here provide valuable information for elucidating the genetic architecture of grain weight and for molecular marker-assisted breeding in grain yield improvement.展开更多
Alien species are one of the most serious threats to the decline and extinction of native amphibian populations. In this study, we examined the predation of invasive Western Mosquitofish Gambusia affinis on the eggs, ...Alien species are one of the most serious threats to the decline and extinction of native amphibian populations. In this study, we examined the predation of invasive Western Mosquitofish Gambusia affinis on the eggs, embryos, and tadpoles of Duttaphrynus melanostictus and Pelophylax nigromaculatus in south China. Our results suggested that the survival of eggs and embryos remaining in the egg capsules of P. nigromaculatus and D. melanostictus was significantly higher than those removed from the egg capsule at 12-h intervals within 72 h in the presence of G. affinis. The survival of P. nigromaculatus eggs and embryos without egg capsules was significantly lower than those of D. melanostictus without egg capsules. The survival of P. nigromaculatus eggs and embryos with egg capsules was significantly higher than those of D. melanostictus with egg capsules from 24 h to 72 h except for 12 h. The survival of D. melanostictus tadpoles was significantly higher than that of P. nigromaculatus tadpoles in the presence of G. affinis. The survival of Gosner stage 26 tadpoles of P. nigromaculatus was significantly higher than that of Gosner stage 30 tadpoles from 12 h to 60 h, but there were no significant differences at 72 h. In contrast, the survival of Gosner stage 26 tadpoles of D. melanostictus was significantly lower than that of Gosner stage 30 tadpoles within 72 h, recording every 12 h. The increasing temperature caused a significant increase in predation by G. affinis on P. nigromaculatus eggs and embryos. The outer jelly capsule surrounding anurans eggs might serve as a mechanical defense against predation by G. affinis due to its large diameter, relatively stationary state and unpalatability. The differences in the vulnerability of P. nigromaculatus and D. melanostictus embryos and tadpoles to G. affinis probably due to differences in the unpalatability, black skin and activity. Based on the magnitude of predation by G. affinis on the eggs, embryos and tadpoles of these two species and the combined impact of temperature, we might speculate that invasive G. affinis and global warming would have more detrimental impacts on population viability of P. nigromaculatus than D. melanostictus in China.展开更多
Kinship and density are believed to affect important ecological processes such as intraspecific competition, predation, growth, development, cannibalism, habitat selection and mate choice, In this work, we used Chines...Kinship and density are believed to affect important ecological processes such as intraspecific competition, predation, growth, development, cannibalism, habitat selection and mate choice, In this work, we used Chinese tiger frog Hoplobatrachus chinensis tadpoles as an experimental model to investigate the effects of kinship and density on growth and development of this species over a 73 day period. The results showed that density can affect the growth and developmental traits （survival rate, larval period, size at the limb bud protrusion/metamorphic climax and body mass at different life stages） of H. chinensis tadpoles, while kinship does not. Tadpoles took longer to develop and potential metamorphosis was greater in high density groups of both sibling and non-siblings. The interaction of kinship and density did not significantly influenced growth traits of H. chinensis tadpoles during the experimental period. For coefficient variations of each growth trait, no differences were detected between sibling and non-sibling groups. These findings provide valuable information on the basic ecology of H. chinensis which will be helpful in future studies of other anuran species.展开更多
Lung cancer is one of the most important causes of cancer-related mortality worldwide. Human cytochrome P450 2A13 enzyme （CYP2A13） is predominantly expressed in the respiratory tract and could catalyze various carci...Lung cancer is one of the most important causes of cancer-related mortality worldwide. Human cytochrome P450 2A13 enzyme （CYP2A13） is predominantly expressed in the respiratory tract and could catalyze various carcinogens. In this study, we quantified CYP2A13 expression in non-small cell lung cancer （NSCLC） tissues and examined the relation between CYP2A13 and clinicopathologic factors. Thirty-five paired lung cancer and normal tissues were studied for the expression of the CYP2A13 gene by using real-time PCR and Western blot- ting assays. We also investigated the relationship between CYP2A13 expression and clinicopathologic factors such as age, gender, histology and lymph node status in tumor tissues. SPSS （17.0） statistical software was applied for data analysis. The real-time PCR results showed that there was no significant difference in the CYP2A13 mRNA transcript levels between tumor and paired normal tissues in the 35 samples and in 12 paired squamous cell car- cinomas. In adenocarcinoma, the expression of CYP2A13 mRNA in tumor tissues was 12.5% of that in adjacent tissues （P 〈 0.05） and it was not associated with age, gender, histology and lymph node status of the patients. The amounts of CYP2A13 proteins detected by Western blotting assays correlated well with those of the correspond- ing mRNAs. In conclusion, the expression of CYP2A13 was downregulated in lung adenocarcinoma. CYP2A13 may be involved in the development and progression of lung adenocarcinoma.展开更多
BACKGROUND： Expression of Fos in neurons of periaqueductal gray （PAG） is used to reflect the excitability. However, changes of expression of Fos in neurons of PAG are caused by injured electrostimulation after simu...BACKGROUND： Expression of Fos in neurons of periaqueductal gray （PAG） is used to reflect the excitability. However, changes of expression of Fos in neurons of PAG are caused by injured electrostimulation after simulated weightlessness, and the relationship between pretreatment and injection of succinylcholine has not been determined yet. OBJECTIVE ： To investigate the changes of expression of Fos in PAG induced by injured electrostimulation pretreatment and injection of succinylcholine at 2 weeks after simulated weightlessness.DESIGN： Observational and controlled animal study.SETTING： Department of Physiology, Medical School, Xi＇an Jiaotong University; Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education. MATERIALS： A total of 24 adult female SD rats, of clean grade and weighing 180-220 g, were selected in this study. METHODS： The experiment was completed in the Experimental Animal Center of Xi＇an Jiaotong University.① All rats were randomly divided into 2 groups according to body mass： simulated weightlessness group and control group with 12 in each group. And then, each group was also divided into 3 subgroups： electrostimulation group, succinylcholine-pretreatment group and succinylcholine-injection group with 4 in each subgroup. ②The model of weightlessness was simulated by tail-suspended female rats, which were described and modified by Cheng Jie. Rats in normal control group were given the same interventions as simulated weightlessness group except for tail-suspended. ③ Experimental method： The rats in electrostimulation group were given nociceptive stimulus by a pair of subcutaneous electrodes inserted into 1 and 5 claw of left hindlimb. The stimulus （current： 10 mA; duration： 1 ms; interval： 1 s） lasted for 30 minutes. The rats in succinylcholine-pretreatment group received stimulus after intravenous administration of succinylcholine, rats in succinylcholine-injection group were not given stimulus, just received succinylcholine. ④ All rats were perfused and fixed after 2 hours from the end of stimulation. The brains were removed, and serial frozen sections of midbrain were stained using immunocytochemical method, observed and taken photos under light-microscope. The number and morphological characters of Fos-immunoreactive （Fos-IR） neurons in ventrolateral part of PAG were investigated. MAIN OUTCOME MEASURES： The alterations in number and morphological characters of Fos-IR neurons in ventrolateral PAG of all rats.RESULTS： A total of 24 rats were involved in the final analysis. ① The morphological changes of Fos-IR neurons： The expressions of Fos in ventrolateral part of PAG were observed in both control and simulated weightlessness groups rats after being given nociceptive stimulus. As compared with control group, Fos-IR neurons in simulated weightlessness group were dyed lightly, cellular integrity was impaired, and cellular verge was unclear. ② The numbers of Fos-IR neurons： In control group, the numbers of Fos-IR neurons in ventrolateral part of PAG in simulated weightlessness group were obviously lower than succinylcholine-pretreatment group, but obviously higher than succinylcholine-injection group （46.94±3.38, 71.06±8.96 and 35.04±4.62, respectively, P 〈 0.05）. In 14-day simulated weightlessness group, the numbers of Fos-IR neurons in electrostimulation group were also obviously lower than succinylcholine-pretreatment group, and obviously higher than succinylcholine-injection group （27.77±3.27, 32.91±2.99 and 11.75±1.00, respectively, P 〈 0.05）. The numbers of Fos-IR neurons in all subgroups in control group were obviously higher than those subgroups in simulated weightlessness group. Compared with electrostimulation group, the percentage of expression of Fos in ventrolateral part of PAG responsed to nociceptive stimulus after administration of succinylcholine （SCH） was increased to 51.83% in control group and 18.51% in simulated weightlessness group.CONCLUSION ：① The expression of Fos in neurons in ventrolateral part of PAG were increased by the pretreatment of SCH before nociceptive stimulus.② Nociceptive stimulus could increase the expression of Fos in neurons in ventrolateral part of PAG. ③ The numbers of Fos-IR neurons in ventrolateral part of PAG were decreased obviously after 2-week simulated weightlessness.展开更多
Superlubricity,a novel lubricity mode ascribing to moirésuperlattice(MSL),has attracted attention in ultra-precise manufacture,microelectronic devices,and national defense areas.Based on incommensurate MSL,nearly...Superlubricity,a novel lubricity mode ascribing to moirésuperlattice(MSL),has attracted attention in ultra-precise manufacture,microelectronic devices,and national defense areas.Based on incommensurate MSL,nearly zero friction can be achieved by eliminating sliding lock-in and offsetting lateral force in principle,and the theoretical foundations are still under extensive investigation.Here,the effects of MSL-induced lattice distortion onπbond and tribological performance in twist MoS_(2)/graphene and MoS_(2)/BN heterointerfaces were studied by first-principles calculations comprehensively.Various contributions of 2pz orbital electron polarization among AA-,AB-,and AC-stacking symmetry areas in different MSL were reflected by band structures to explain the sensitivity ofπbond to MSL.Theπbond perpendicular to the atomic plane depended closely on interfacial distortion,which can not only influence the local distribution of intralayer bond strength but also determine the interlayer charge redistribution.Meanwhile,the interfacial potential energy was changed with the interlayer interaction fluctuation caused by twist angle and atomic stacking modes.Through evaluating the energy barriers and lateral force,MoS_(2)/BN with a twist angle of 20.79°exhibited superlubricity.Moreover,the connection among sliding energy barriers,twist angles,and specific electronic structures has been bridged paving a path to reveal the superlubricity mechanism of two-dimensional materials withπbond.展开更多
BACKGROUND： Prenatal stress has been shown to inhibit cell proliferation in the dentate gyrus and hippocampus, reduce hippocampal volume, and cause neuronal loss and oxidative damage in the hippocampus of offspring r...BACKGROUND： Prenatal stress has been shown to inhibit cell proliferation in the dentate gyrus and hippocampus, reduce hippocampal volume, and cause neuronal loss and oxidative damage in the hippocampus of offspring rats, but the sexual difference of the effects on offsprings is seldom referred to. OBJECTIVE： To observe the effect of prenatal stress to adult pregnant rats on expression of extracellular signal-regulated kinases （ERK） in hippocampus of the offspring rats of different genders. DESIGN ： A randomized and control animal experiment.SETTING： Department of Physiology and Pathophysiology, School of Medicine, Xi＇an Jiaotong University. MATERIALS ： The experiments were carried out in the Key Laboratory of Environment and Gene Related Diseases （Xi＇an Jiaotong University）, Ministry of Education between October 2005 and March 2006. Fifteen female and five male adult Sprague-Dawley rats were adopted. Female rats weighing 230-250 g and male rats weighing 280-350 g were used. METHODS： The virgin female rats were placed overnight with adult male rats （3：1） for mating. A total of twelve pregnant rats were randomly assigned to prenatal stress group （PNS group, n=6） and control group （n=6）. The pregnant rats of the PNS group were exposed to restraint stress on days 14-20 of pregnancy three times a day, 45 minutes for each time . The restraint device was a transparent plastic tube （6.8 cm in diameter） with air holes for breathing and closed end. The length could be adjusted to accommodate the size of the animals. To prevent habituation of animals to the daily procedure, restraint periods were randomly shifted within certain time periods （8：00-11：00, 11：00-14：00, and 16：00-19：00）. After birth, offsprings of all groups were culled to 8-10 litters in each group and housed in the same animal room, and kept together with their biologic mothers. The pregnant rats of the control group were left undisturbed. On day 21, after all the offspring were weaned, male and female pups were separated and housed four in each cage respectively until test at 30 days of age. At the end of postnatal day 30, one male and female offspring rats from the same dam were selected with a random choice and a total of 24 animals from 12 different dams were used. The experimental rats were sacrificed by decapitation under anesthesia. Bilateral hippocampal tissues were isolated and homogenized in cold condition. Alkaline carbonate buffer （BCA） method was used to detect the concentration of extracellular signal-regulated kinases （ERK）, then mixed with loading buffer, the constant voltage was 100 V. Finally, BCIP/NBT staining and electrDphoresis were performed, the absorbance （A） value for the bands was detected with the Bandscan analytical software, and the expression of ERK in hippocampus of offspring rats of different genders in each group was quantitatively analyzed. MAIN OUTCOME MEASURES： The level of ERK expression in hippocampus of offspring rats of different genders in each group was observed.RESULTS： All the 24 offspring rats were involved in the analysis of results. ① The staining results of ERP activity in the extract of brain tissue detected with Western blotting technique and specific antibody analysis showed that the ERP in hippocampus of offspring rats had two subtypes of ERK-1 and ERK-2, and the latter was the main type.② Standardized by the average A value in the control group, the quantitative data of the general A value of total ERK showed that the expression of ERK-2 in hippocampus of female offspring rats was obviously higher in the PNS group than in the control group （A value： 126±6.76,100±4.89,P〈 0.01）. ③The expression of ERK-2 had no obvious difference between the female and male offspring rats in the control group.④ The expression of ERK-2 in hippocampus of male offspring rats was a little higher in the PNS group than in the control group （A value： 104±6.27,102±5.48,P 〉 0.05）. CONCLUSION ： PNS significantly affects the increase of ERK expression in hippocampus of female offspring rats, but has no obvious influence on that of male ones.展开更多
The biomimetic materials that replicate the mechanical gradient transitions from muscle to tendon to bone remain a significant challenge in tissue engineering,particularly through simple and environmentally friendly a...The biomimetic materials that replicate the mechanical gradient transitions from muscle to tendon to bone remain a significant challenge in tissue engineering,particularly through simple and environmentally friendly approaches.This mechanical gradient is crucial for applications such as rotator cuff and Achilles tendon repair patches,which prevent stress shielding and ensure uniform stress distribution,addressing the stress concentration issues common in traditional repairs.Here,we present a strategy that achieves high strength even at high water content,enabling programmable modulus/structural gradients with broad applicability.Using rotator cuff tendon repair as a model system,we demonstrate successful in vivo tissue regeneration with integrated real-time sensing capabilities,providing quantitative data for rehabilitation protocols.The hydrogels exhibit precisely controlled regional mechanical properties and seamless interface transitions,mimicking the hierarchical structure of native tissue.This approach not only improves healing outcomes compared to conventional methods but also establishes a quantitative standard for rehabilitation training.展开更多
In HfO_(2),the stabilization of orthorhombic phase is crucial for hafnia-based ferroelectric devices.Here,we propose a charge-balance synergistic strategy to modulate phase transition and optimize ferroelectric proper...In HfO_(2),the stabilization of orthorhombic phase is crucial for hafnia-based ferroelectric devices.Here,we propose a charge-balance synergistic strategy to modulate phase transition and optimize ferroelectric properties in acceptor-doped HfO_(2)thin-film heterostructures.Sm-doped HfO_(2)/SrRuO_(3)heterostructures are adopted as the platform,in which the acceptor SmʹHf introduces extra holes into the HfO_(2)controlled by doping concentration,while the SrRuO_(3)electrode injects electrons depended on termination-controlled surface work function.Transition from monoclinic to orthorhombic and then to tetragonal phase is observed with increasing Sm concentration.The Sm-doping region for improved ferroelectricity is found to be depended on SrRuO_(3)termination.These behaviors are ascribed to the charge-balance effect that combines the acceptor doping and the interface injection in the heterostructures.The holes in HfO_(2)lattices are thus modulated to dominantly distribute on specific oxygen sublattices,lowering the relative energy between monoclinic and orthorhombic phases.We also extend the study into other acceptor-doped HfO_(2),such as La^(3+)and Eu^(3+),and observe almost identical phase transition and ferroelectric behaviors.Our findings provide more physical insights into the stabilization of orthorhombic phase and open a new gateway for designing high-performance ferroelectric HfO_(2)devices by harnessing both the electrode structures and the HfO_(2)-based layers in heterostructure systems.展开更多
Water friction in nanoconfinement is of great importance in water lubrication and membrane-based applications,yet remains fraught with doubts despite great efforts.Our molecular dynamics simulations demonstrate that t...Water friction in nanoconfinement is of great importance in water lubrication and membrane-based applications,yet remains fraught with doubts despite great efforts.Our molecular dynamics simulations demonstrate that the first water layer adjacent to the surface plays an important role in interfacial friction.Applying a uniform strain to the surface(changing the lattice constant)can induce a significant change in friction and is quite different for the hydrophilic and hydrophobic cases.Specifically,in the hydrophilic case,there is maximum friction when the lattice constant approaches the preferential oxygen‒oxygen distance of the first water layer(a constant value),and the further it deviates,the smaller the friction.The maximum friction corresponds to the most ordered first water layer.While in the hydrophobic case,the friction increases monotonically with increasing lattice constant,which hardly changes the first water layer structure but only increases the difficulty of water molecular jump(meaning jump from one equilibrium position to another).Starting from the molecular jump in the first water layer,theoretical dependence of friction on the molecular activation barrier and shear velocity is established,which provides a reasonable explanation for the friction behavior.Moreover,the water transport behavior in nanochannels supports the finding of the friction dependence on the lattice constant,suggesting great potential for improving and controlling water transport.Our results not only provide a novel understanding of nanoconfined water friction but are also instructive for friction control and water transport.展开更多
Crystal orientation governs the plasticity of intermetallic alloys,yet the atomicscale mechanisms linking defect dynamics to mechanical properties remain elusive.Here,we unveil unprecedented deformation pathways in si...Crystal orientation governs the plasticity of intermetallic alloys,yet the atomicscale mechanisms linking defect dynamics to mechanical properties remain elusive.Here,we unveil unprecedented deformation pathways in single-crystal γ-TiAl through largescale molecular dynamics simulations under uniaxial tension across four crystallographic orientations:[100],[112],[110],and[111].Strikingly,a metastable body-centered cubic(BCC)phase emerges transiently during[100]-oriented stretching,acting as a critical bridge between elastic and plastic regimes—a phenomenon unreported in γ-TiAl.For[110]and[111]orientations,we identify a hierarchical defect evolution cascade(intrinsic stacking faults→extrinsic stacking faults→twin boundary(ISF→ESF→TB))driven by intersecting stacking faults and Shockley partial dislocation interactions,which govern twin boundary nucleation and growth.In contrast,[112]-oriented deformation adheres to conventional dislocation-mediated plasticity.These findings reveal how crystallographic anisotropy dictates defect dynamics,offering atomic-scale insights into deformation twinning and transient phase transitions.This work bridges atomistic processes to macroscopic properties,advancing the design of next-generation lightweight hightemperature materials.展开更多
Studying the regulatory mechanisms that drive nitrogen-use efficiency(NUE)in crops is important for sustainable agriculture and environmental protection.In this study,we generated a high-quality genome assembly for th...Studying the regulatory mechanisms that drive nitrogen-use efficiency(NUE)in crops is important for sustainable agriculture and environmental protection.In this study,we generated a high-quality genome assembly for the high-NUE wheat cultivar Kenong 9204 and systematically analyzed genes related to nitrogen uptake and metabolism.By comparative analyses,we found that the high-affinity nitrate transporter gene family had expanded in Triticeae.Further studies showed that subsequent functional differentiation endowed the expanded family members with saline inducibility,providing a genetic basis for improving the adaptability of wheat to nitrogen deficiency in various habitats.To explore the genetic and molecular mechanisms of high NUE,we compared genomic and transcriptomic data from the high-NUE cultivar Kenong 9204(KN9204)and the low-NUE cultivar Jing 411 and quantified their nitrogen accumulation under high-and low-nitrogen conditions.Compared with Jing 411,KN9204 absorbed significantly more nitrogen at the reproductive stage after shooting and accumulated it in the shoots and seeds.Transcriptome data analysis revealed that nitrogen deficiency clearly suppressed the expression of genes related to cell division in the young spike of Jing 411,whereas this suppression of gene expression was much lower in KN9204.In addition,KN9204 maintained relatively high expression of NPF genes for a longer time than Jing 411 during seed maturity.Physiological and transcriptome data revealed that KN9204 was more tolerant of nitrogen deficiency than Jing 411,especially at the reproductive stage.The high NUE of KN9204 is an integrated effect controlled at different levels.Taken together,our data provide new insights into the molecular mechanisms of NUE and important gene resources for improving wheat cultivars with a higher NUE trait.展开更多
基金The authors are grateful for the support and funding from National Scientific Research Project(Basis Strengthening Plan)State Key Laboratory of Solidification Processing in NWPU(No.SKLSP202103).
文摘Bisphenol A dicyanate ester resins modified by fluorine-containing liquid crystal compound(LCFE)are applied as polymer matrix(LCFE-BADCy),poly(p-phenylene-2,6-benzobisoxazole)(PBO)fibers as rein-forcements,and fluorine/adamantane PBO precursor(pre FABPBO)as interfacial compatibilizer to prepare the corresponding PBO fibers/FABPBO/LCFE-BADCy wave-transparent laminated composites.LCFE could improve the order degree of BADCy cured network,in favor of enhancing the wave-transparent perfor-mance,mechanical properties,and intrinsic thermal conductivity.The dielectric constant and dielectric loss of PBO fibers/FABPBO/LCFE-BADCy composites are highly temperature(25–200℃)and frequency(10^(4)–10^(7) Hz and 8.2–12.4 GHz)stable with the value of 2.49 and 0.003 under 10^(6) Hz at 25℃,and the corresponding wave transmission efficiency is 95.0%,higher than that of 92.5%for PBO fibers/BADCy com-posites.The interlamellar shear strength and flexural strength are respectively 50.7 MPa and 682.5 MPa,38.1%and 16.2%higher than those of PBO fibers/BADCy composites.Besides,the volume resistivity,breakdown voltage,heat resistance index,glass transition temperature,flame retardant grade,and ul-timate oxygen index of PBO fibers/FABPBO/LCFE-BADCy composites are respectively 5.3×10^(15)Ωcm,29.75 kV/mm,217.2℃,245.7℃,V-1 grade,and 33.6%,expected to be performed as a new generation of“lightweight/loading/wave-transparent”electromagnetic window materials in advanced military weapons and civil communication base station.
基金supported by the grants from the National Natural Science Foundation of China(30770310,30970435)the Natural Science Foundation of Zhejiang,China(Y307453)
文摘Advertisement calls play an important role in influencing female mate choice and are regarded as one of the key characters responsible for reproductive isolation and speciation events in frogs and toads. The black-spined toad, Bufo melanostictus, is one of the most common amphibians in Southeast Asia and is frequently observed in human habitations throughout its distributional range. The advertisement calls of the toad have not been well described. Here, we report the advertisement calls of this species from Lishui, Zhejiang, China during its breeding season. The advertisement calls of B. melanostictus are composed of single notes with a single harmonic frequency emitted sporadically. The call parameters recorded in this study were highly variable across recording times and with different body sizes. Dominant frequency was negatively correlated with body size. Comparing the calls of the B. melanostictus population from Lishui with the populations from five other localities(Bangkok, Thailand; Coorg, India; Burma, Myanmar; Bali, Indonesia; Halimun-Salak National Park, Indonesia), we found that call structure was similar among five different populations with no harmonics, while the Halimun-Salak National Park population contained two clear harmonics. Dominant frequency was similar between Bali(1.56 kHz) and Coorg(1.6 kHz) populations, while it was highly variable among other populations. Besides call duration, call interval and pulse/call rate may also be significantly different among the comparing populations. Pooling the available data, we observed some similarities and differences in call parameters among the six populations.
基金This work was financially supported by the National Key Research and Development Program of China(2018YFB0703801,2018YFB0703802,2016YFB0701303,and 2016YFB0701304)CRRC Tangshan Co.,Ltd.(201750463031).Special thanks to Professor Hong Wang at Shanghai Jiao Tong University for the fruitful discussions and the constructive suggestions/comments.
文摘A data identifier(DID)is an essential tag or label in all kinds of databases—particularly those related to integrated computational materials engineering(ICME),inheritable integrated intelligent manufacturing(I3M),and the Industrial Internet ofThings.With the guidance and quick acceleration of the developme nt of advanced materials,as envisioned by official documents worldwide,more investigations are required to construct relative numerical standards for material informatics.This work proposes a universal DID format consisting of a set of build chains,which aligns with the classical form of identifier in both international and national standards,such as ISO/IEC 29168-1:2000,GB/T 27766-2011,GA/T 543.2-2011,GM/T 0006-2012,GJB 7365-2011,SL 325-2014,SL 607-201&WS 363.2-2011,and QX/T 39-2005.Each build chain is made up of capital letters and numbers,with no symbols.Moreover,the total length of each build chain is not restricted,which follows the formation of the Universal Coded Character Set in the international standard of ISO/IEC 10646.Based on these rules,the proposed DID is flexible and convenient for extendi ng and sharing in and between various cloud-based platforms.Accordingly,classical two-dimensional(2D)codes,including the Hanxin Code,Lots Perception Matrix(LP)Code,Quick Response(Q.R)code,Grid Matrix(GM)code,and Data Matrix(DM)Code,can be constructed and precisely recognized and/or decoded by either smart phones or specific machines.By utilizing these 2D codes as the fingerprints of a set of data linked with cloud-based platforms,progress and updates in the composition-processing-structure-property-performance workflow process can be tracked spontaneously,paving a path to accelerate the discovery and manufacture of advanced materials and enhance research productivity,performance,and collaboration.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA24030402)Sichuan Science and Technology Program.
文摘Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was constructed to detect QTL for thousand-grain weight(TGW),grain length(GL)and grain width(GW)across eight environments.Genomic regions associated with grain size and grain weight were identified on chromosomes 4A and 6A using bulked segregant exome sequencing(BSE-Seq)analysis.After constructing genetic maps,six major QTL detected in at least four individual environments and in best linear unbiased estimator(BLUE)datasets,explained 7.50%-23.45%of the phenotypic variation.Except for QGl.cib-4A,the other five QTL were co-located in two regions,namely QTgw/Gw.cib-4A and QTgw/Gw/Gl.cib-6A.Interactions of these QTL were analyzed.Unlike QTgw/Gw/Gl.cib-6A,QTgw/Gw.cib-4A and QGl.cib-4A had no effect on grain number per spike(GNS).The QTL were validated in a second cross using Kompetitive Allele Specific PCR(KASP)markers.Since QTgw/Gw.cib-4A was probably a novel locus,it and the KASP markers reported here can be used in wheat breeding.TraesCS4A03G0191200 was predicted to be potential candidate gene for QTgw/Gw.cib-4A based on the sequence differences,spatiotemporal expression patterns,gene annotation and haplotype analysis.Our findings will be useful for fine mapping and for marker-assisted selection in wheat grain yield improvement.
基金supported by the Major Program of National Agricultural Science and Technology of China(NK20220607)the West Light Foundation of the Chinese Academy of Sciences(2022XBZG_XBQNXZ_A_001)the Sichuan Science and Technology Program,China(2022ZDZX0014)。
文摘Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(RIL)population derived from a cross between W7268 and Chuanyu 12(CY12)was employed to detect quantitative trait loci(QTLs)for thousand-grain weight(TGW),grain length(GL),grain width(GW),and the ratio of grain length to width(GLW)in six environments.Seven major QTLs,QGl.cib-2D,QGw.cib-2D,QGw.cib-3B,QGw.cib-4B.1,QGlw.cib-2D.1,QTgw.cib-2D.1 and QTgw.cib-3B.1,were consistently identified in at least four environments and the best linear unbiased estimation(BLUE)datasets,and they explained 2.61 to 34.85%of the phenotypic variance.Significant interactions were detected between the two major TGW QTLs and three major GW loci.In addition,QTgw.cib-3B.1 and QGw.cib-3B were co-located,and the improved TGW at this locus was contributed by GW.Unlike other loci,QTgw.cib-3B.1/QGw.cib-3B had no effect on grain number per spike(GNS).They were further validated in advanced lines using Kompetitive Allele Specific PCR(KASP)markers,and a comparison analysis indicated that QTgw.cib-3B.1/QGw.cib-3B is likely a novel locus.Six haplotypes were identified in the region of this QTL and their distribution frequencies varied between the landraces and cultivars.According to gene annotation,spatial expression patterns,ortholog analysis and sequence variation,the candidate gene of QTgw.cib-3B.1/QGw.cib-3B was predicted.Collectively,the major QTLs and KASP markers reported here provide valuable information for elucidating the genetic architecture of grain weight and for molecular marker-assisted breeding in grain yield improvement.
基金funded by grants from the National Natural Science Foundation of China(31270443,31500329)the Science Foundation of Zhejiang Provincial Committee of Education(Y201534237)the Scientific Research Foundation of Ph.D.,Lishui University(QD1423)
文摘Alien species are one of the most serious threats to the decline and extinction of native amphibian populations. In this study, we examined the predation of invasive Western Mosquitofish Gambusia affinis on the eggs, embryos, and tadpoles of Duttaphrynus melanostictus and Pelophylax nigromaculatus in south China. Our results suggested that the survival of eggs and embryos remaining in the egg capsules of P. nigromaculatus and D. melanostictus was significantly higher than those removed from the egg capsule at 12-h intervals within 72 h in the presence of G. affinis. The survival of P. nigromaculatus eggs and embryos without egg capsules was significantly lower than those of D. melanostictus without egg capsules. The survival of P. nigromaculatus eggs and embryos with egg capsules was significantly higher than those of D. melanostictus with egg capsules from 24 h to 72 h except for 12 h. The survival of D. melanostictus tadpoles was significantly higher than that of P. nigromaculatus tadpoles in the presence of G. affinis. The survival of Gosner stage 26 tadpoles of P. nigromaculatus was significantly higher than that of Gosner stage 30 tadpoles from 12 h to 60 h, but there were no significant differences at 72 h. In contrast, the survival of Gosner stage 26 tadpoles of D. melanostictus was significantly lower than that of Gosner stage 30 tadpoles within 72 h, recording every 12 h. The increasing temperature caused a significant increase in predation by G. affinis on P. nigromaculatus eggs and embryos. The outer jelly capsule surrounding anurans eggs might serve as a mechanical defense against predation by G. affinis due to its large diameter, relatively stationary state and unpalatability. The differences in the vulnerability of P. nigromaculatus and D. melanostictus embryos and tadpoles to G. affinis probably due to differences in the unpalatability, black skin and activity. Based on the magnitude of predation by G. affinis on the eggs, embryos and tadpoles of these two species and the combined impact of temperature, we might speculate that invasive G. affinis and global warming would have more detrimental impacts on population viability of P. nigromaculatus than D. melanostictus in China.
基金supported by the grants from the National Natural Science Foundation of China (30970435,31270443)the Natural Science Foundation of Zhejiang, China (LY13C030004)
文摘Kinship and density are believed to affect important ecological processes such as intraspecific competition, predation, growth, development, cannibalism, habitat selection and mate choice, In this work, we used Chinese tiger frog Hoplobatrachus chinensis tadpoles as an experimental model to investigate the effects of kinship and density on growth and development of this species over a 73 day period. The results showed that density can affect the growth and developmental traits （survival rate, larval period, size at the limb bud protrusion/metamorphic climax and body mass at different life stages） of H. chinensis tadpoles, while kinship does not. Tadpoles took longer to develop and potential metamorphosis was greater in high density groups of both sibling and non-siblings. The interaction of kinship and density did not significantly influenced growth traits of H. chinensis tadpoles during the experimental period. For coefficient variations of each growth trait, no differences were detected between sibling and non-sibling groups. These findings provide valuable information on the basic ecology of H. chinensis which will be helpful in future studies of other anuran species.
基金supported by the Project sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry (No.Z2005-2-45006)
文摘Lung cancer is one of the most important causes of cancer-related mortality worldwide. Human cytochrome P450 2A13 enzyme （CYP2A13） is predominantly expressed in the respiratory tract and could catalyze various carcinogens. In this study, we quantified CYP2A13 expression in non-small cell lung cancer （NSCLC） tissues and examined the relation between CYP2A13 and clinicopathologic factors. Thirty-five paired lung cancer and normal tissues were studied for the expression of the CYP2A13 gene by using real-time PCR and Western blot- ting assays. We also investigated the relationship between CYP2A13 expression and clinicopathologic factors such as age, gender, histology and lymph node status in tumor tissues. SPSS （17.0） statistical software was applied for data analysis. The real-time PCR results showed that there was no significant difference in the CYP2A13 mRNA transcript levels between tumor and paired normal tissues in the 35 samples and in 12 paired squamous cell car- cinomas. In adenocarcinoma, the expression of CYP2A13 mRNA in tumor tissues was 12.5% of that in adjacent tissues （P 〈 0.05） and it was not associated with age, gender, histology and lymph node status of the patients. The amounts of CYP2A13 proteins detected by Western blotting assays correlated well with those of the correspond- ing mRNAs. In conclusion, the expression of CYP2A13 was downregulated in lung adenocarcinoma. CYP2A13 may be involved in the development and progression of lung adenocarcinoma.
基金the National Natural Science Foundation of China, No. 30300106
文摘BACKGROUND： Expression of Fos in neurons of periaqueductal gray （PAG） is used to reflect the excitability. However, changes of expression of Fos in neurons of PAG are caused by injured electrostimulation after simulated weightlessness, and the relationship between pretreatment and injection of succinylcholine has not been determined yet. OBJECTIVE ： To investigate the changes of expression of Fos in PAG induced by injured electrostimulation pretreatment and injection of succinylcholine at 2 weeks after simulated weightlessness.DESIGN： Observational and controlled animal study.SETTING： Department of Physiology, Medical School, Xi＇an Jiaotong University; Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education. MATERIALS： A total of 24 adult female SD rats, of clean grade and weighing 180-220 g, were selected in this study. METHODS： The experiment was completed in the Experimental Animal Center of Xi＇an Jiaotong University.① All rats were randomly divided into 2 groups according to body mass： simulated weightlessness group and control group with 12 in each group. And then, each group was also divided into 3 subgroups： electrostimulation group, succinylcholine-pretreatment group and succinylcholine-injection group with 4 in each subgroup. ②The model of weightlessness was simulated by tail-suspended female rats, which were described and modified by Cheng Jie. Rats in normal control group were given the same interventions as simulated weightlessness group except for tail-suspended. ③ Experimental method： The rats in electrostimulation group were given nociceptive stimulus by a pair of subcutaneous electrodes inserted into 1 and 5 claw of left hindlimb. The stimulus （current： 10 mA; duration： 1 ms; interval： 1 s） lasted for 30 minutes. The rats in succinylcholine-pretreatment group received stimulus after intravenous administration of succinylcholine, rats in succinylcholine-injection group were not given stimulus, just received succinylcholine. ④ All rats were perfused and fixed after 2 hours from the end of stimulation. The brains were removed, and serial frozen sections of midbrain were stained using immunocytochemical method, observed and taken photos under light-microscope. The number and morphological characters of Fos-immunoreactive （Fos-IR） neurons in ventrolateral part of PAG were investigated. MAIN OUTCOME MEASURES： The alterations in number and morphological characters of Fos-IR neurons in ventrolateral PAG of all rats.RESULTS： A total of 24 rats were involved in the final analysis. ① The morphological changes of Fos-IR neurons： The expressions of Fos in ventrolateral part of PAG were observed in both control and simulated weightlessness groups rats after being given nociceptive stimulus. As compared with control group, Fos-IR neurons in simulated weightlessness group were dyed lightly, cellular integrity was impaired, and cellular verge was unclear. ② The numbers of Fos-IR neurons： In control group, the numbers of Fos-IR neurons in ventrolateral part of PAG in simulated weightlessness group were obviously lower than succinylcholine-pretreatment group, but obviously higher than succinylcholine-injection group （46.94±3.38, 71.06±8.96 and 35.04±4.62, respectively, P 〈 0.05）. In 14-day simulated weightlessness group, the numbers of Fos-IR neurons in electrostimulation group were also obviously lower than succinylcholine-pretreatment group, and obviously higher than succinylcholine-injection group （27.77±3.27, 32.91±2.99 and 11.75±1.00, respectively, P 〈 0.05）. The numbers of Fos-IR neurons in all subgroups in control group were obviously higher than those subgroups in simulated weightlessness group. Compared with electrostimulation group, the percentage of expression of Fos in ventrolateral part of PAG responsed to nociceptive stimulus after administration of succinylcholine （SCH） was increased to 51.83% in control group and 18.51% in simulated weightlessness group.CONCLUSION ：① The expression of Fos in neurons in ventrolateral part of PAG were increased by the pretreatment of SCH before nociceptive stimulus.② Nociceptive stimulus could increase the expression of Fos in neurons in ventrolateral part of PAG. ③ The numbers of Fos-IR neurons in ventrolateral part of PAG were decreased obviously after 2-week simulated weightlessness.
基金financially supported by the National Key Re-search and Development Program of China(Nos.2018YFB0703801 and 2018YFB0703802)the Foundation for Doctor Dissertation of Northwestern Polytechnical University(No.CX2021064)。
文摘Superlubricity,a novel lubricity mode ascribing to moirésuperlattice(MSL),has attracted attention in ultra-precise manufacture,microelectronic devices,and national defense areas.Based on incommensurate MSL,nearly zero friction can be achieved by eliminating sliding lock-in and offsetting lateral force in principle,and the theoretical foundations are still under extensive investigation.Here,the effects of MSL-induced lattice distortion onπbond and tribological performance in twist MoS_(2)/graphene and MoS_(2)/BN heterointerfaces were studied by first-principles calculations comprehensively.Various contributions of 2pz orbital electron polarization among AA-,AB-,and AC-stacking symmetry areas in different MSL were reflected by band structures to explain the sensitivity ofπbond to MSL.Theπbond perpendicular to the atomic plane depended closely on interfacial distortion,which can not only influence the local distribution of intralayer bond strength but also determine the interlayer charge redistribution.Meanwhile,the interfacial potential energy was changed with the interlayer interaction fluctuation caused by twist angle and atomic stacking modes.Through evaluating the energy barriers and lateral force,MoS_(2)/BN with a twist angle of 20.79°exhibited superlubricity.Moreover,the connection among sliding energy barriers,twist angles,and specific electronic structures has been bridged paving a path to reveal the superlubricity mechanism of two-dimensional materials withπbond.
基金the National Natural Science Foundation of China, No. 30270445
文摘BACKGROUND： Prenatal stress has been shown to inhibit cell proliferation in the dentate gyrus and hippocampus, reduce hippocampal volume, and cause neuronal loss and oxidative damage in the hippocampus of offspring rats, but the sexual difference of the effects on offsprings is seldom referred to. OBJECTIVE： To observe the effect of prenatal stress to adult pregnant rats on expression of extracellular signal-regulated kinases （ERK） in hippocampus of the offspring rats of different genders. DESIGN ： A randomized and control animal experiment.SETTING： Department of Physiology and Pathophysiology, School of Medicine, Xi＇an Jiaotong University. MATERIALS ： The experiments were carried out in the Key Laboratory of Environment and Gene Related Diseases （Xi＇an Jiaotong University）, Ministry of Education between October 2005 and March 2006. Fifteen female and five male adult Sprague-Dawley rats were adopted. Female rats weighing 230-250 g and male rats weighing 280-350 g were used. METHODS： The virgin female rats were placed overnight with adult male rats （3：1） for mating. A total of twelve pregnant rats were randomly assigned to prenatal stress group （PNS group, n=6） and control group （n=6）. The pregnant rats of the PNS group were exposed to restraint stress on days 14-20 of pregnancy three times a day, 45 minutes for each time . The restraint device was a transparent plastic tube （6.8 cm in diameter） with air holes for breathing and closed end. The length could be adjusted to accommodate the size of the animals. To prevent habituation of animals to the daily procedure, restraint periods were randomly shifted within certain time periods （8：00-11：00, 11：00-14：00, and 16：00-19：00）. After birth, offsprings of all groups were culled to 8-10 litters in each group and housed in the same animal room, and kept together with their biologic mothers. The pregnant rats of the control group were left undisturbed. On day 21, after all the offspring were weaned, male and female pups were separated and housed four in each cage respectively until test at 30 days of age. At the end of postnatal day 30, one male and female offspring rats from the same dam were selected with a random choice and a total of 24 animals from 12 different dams were used. The experimental rats were sacrificed by decapitation under anesthesia. Bilateral hippocampal tissues were isolated and homogenized in cold condition. Alkaline carbonate buffer （BCA） method was used to detect the concentration of extracellular signal-regulated kinases （ERK）, then mixed with loading buffer, the constant voltage was 100 V. Finally, BCIP/NBT staining and electrDphoresis were performed, the absorbance （A） value for the bands was detected with the Bandscan analytical software, and the expression of ERK in hippocampus of offspring rats of different genders in each group was quantitatively analyzed. MAIN OUTCOME MEASURES： The level of ERK expression in hippocampus of offspring rats of different genders in each group was observed.RESULTS： All the 24 offspring rats were involved in the analysis of results. ① The staining results of ERP activity in the extract of brain tissue detected with Western blotting technique and specific antibody analysis showed that the ERP in hippocampus of offspring rats had two subtypes of ERK-1 and ERK-2, and the latter was the main type.② Standardized by the average A value in the control group, the quantitative data of the general A value of total ERK showed that the expression of ERK-2 in hippocampus of female offspring rats was obviously higher in the PNS group than in the control group （A value： 126±6.76,100±4.89,P〈 0.01）. ③The expression of ERK-2 had no obvious difference between the female and male offspring rats in the control group.④ The expression of ERK-2 in hippocampus of male offspring rats was a little higher in the PNS group than in the control group （A value： 104±6.27,102±5.48,P 〉 0.05）. CONCLUSION ： PNS significantly affects the increase of ERK expression in hippocampus of female offspring rats, but has no obvious influence on that of male ones.
基金supported by the Fundamental Research Funds for the Central Universities(No.2022JC013)National NaturalScience Foundation of China(Grant No.12204271)+1 种基金Natural Science Foundation of Shandong Province of China(No.ZR2021MH023)National Natural Science Foundation of China(No.62401343).
文摘The biomimetic materials that replicate the mechanical gradient transitions from muscle to tendon to bone remain a significant challenge in tissue engineering,particularly through simple and environmentally friendly approaches.This mechanical gradient is crucial for applications such as rotator cuff and Achilles tendon repair patches,which prevent stress shielding and ensure uniform stress distribution,addressing the stress concentration issues common in traditional repairs.Here,we present a strategy that achieves high strength even at high water content,enabling programmable modulus/structural gradients with broad applicability.Using rotator cuff tendon repair as a model system,we demonstrate successful in vivo tissue regeneration with integrated real-time sensing capabilities,providing quantitative data for rehabilitation protocols.The hydrogels exhibit precisely controlled regional mechanical properties and seamless interface transitions,mimicking the hierarchical structure of native tissue.This approach not only improves healing outcomes compared to conventional methods but also establishes a quantitative standard for rehabilitation training.
基金sponsored by Natural Science Foundation of China(Grants No.52372113 and 12474061)Natural Science Basic Research Program of Shaanxi(Program No.2024JC-YBMS-009)+1 种基金Z.W.acknowledges support from the Taishan Scholar Program of Shandong Province(Grants No.tstp20240511)T.C.thanks the support from the Youth Project of“Shanxi High-level Talents Introduction Plan and Shaanxi Qinchuangyuan High-Level Innovative and Entrepreneurial Talent Introduction Program(QCYRCXM-2023-077)。
文摘In HfO_(2),the stabilization of orthorhombic phase is crucial for hafnia-based ferroelectric devices.Here,we propose a charge-balance synergistic strategy to modulate phase transition and optimize ferroelectric properties in acceptor-doped HfO_(2)thin-film heterostructures.Sm-doped HfO_(2)/SrRuO_(3)heterostructures are adopted as the platform,in which the acceptor SmʹHf introduces extra holes into the HfO_(2)controlled by doping concentration,while the SrRuO_(3)electrode injects electrons depended on termination-controlled surface work function.Transition from monoclinic to orthorhombic and then to tetragonal phase is observed with increasing Sm concentration.The Sm-doping region for improved ferroelectricity is found to be depended on SrRuO_(3)termination.These behaviors are ascribed to the charge-balance effect that combines the acceptor doping and the interface injection in the heterostructures.The holes in HfO_(2)lattices are thus modulated to dominantly distribute on specific oxygen sublattices,lowering the relative energy between monoclinic and orthorhombic phases.We also extend the study into other acceptor-doped HfO_(2),such as La^(3+)and Eu^(3+),and observe almost identical phase transition and ferroelectric behaviors.Our findings provide more physical insights into the stabilization of orthorhombic phase and open a new gateway for designing high-performance ferroelectric HfO_(2)devices by harnessing both the electrode structures and the HfO_(2)-based layers in heterostructure systems.
基金financial support from the National Natural Science Foundation of China(No.22032006)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB047020104).
文摘Water friction in nanoconfinement is of great importance in water lubrication and membrane-based applications,yet remains fraught with doubts despite great efforts.Our molecular dynamics simulations demonstrate that the first water layer adjacent to the surface plays an important role in interfacial friction.Applying a uniform strain to the surface(changing the lattice constant)can induce a significant change in friction and is quite different for the hydrophilic and hydrophobic cases.Specifically,in the hydrophilic case,there is maximum friction when the lattice constant approaches the preferential oxygen‒oxygen distance of the first water layer(a constant value),and the further it deviates,the smaller the friction.The maximum friction corresponds to the most ordered first water layer.While in the hydrophobic case,the friction increases monotonically with increasing lattice constant,which hardly changes the first water layer structure but only increases the difficulty of water molecular jump(meaning jump from one equilibrium position to another).Starting from the molecular jump in the first water layer,theoretical dependence of friction on the molecular activation barrier and shear velocity is established,which provides a reasonable explanation for the friction behavior.Moreover,the water transport behavior in nanochannels supports the finding of the friction dependence on the lattice constant,suggesting great potential for improving and controlling water transport.Our results not only provide a novel understanding of nanoconfined water friction but are also instructive for friction control and water transport.
基金financial support by the National Science and Technology Major Project(No.2025ZD0618600)the General Projects for Key Industrial Chain Technology Research and Development of Xi'an(No.24ZDCYJSGG0050)the Key Technology Project of Ningbo"Science and Technology Innovation Yongjiang 2035"(No.2024Z155).
文摘Crystal orientation governs the plasticity of intermetallic alloys,yet the atomicscale mechanisms linking defect dynamics to mechanical properties remain elusive.Here,we unveil unprecedented deformation pathways in single-crystal γ-TiAl through largescale molecular dynamics simulations under uniaxial tension across four crystallographic orientations:[100],[112],[110],and[111].Strikingly,a metastable body-centered cubic(BCC)phase emerges transiently during[100]-oriented stretching,acting as a critical bridge between elastic and plastic regimes—a phenomenon unreported in γ-TiAl.For[110]and[111]orientations,we identify a hierarchical defect evolution cascade(intrinsic stacking faults→extrinsic stacking faults→twin boundary(ISF→ESF→TB))driven by intersecting stacking faults and Shockley partial dislocation interactions,which govern twin boundary nucleation and growth.In contrast,[112]-oriented deformation adheres to conventional dislocation-mediated plasticity.These findings reveal how crystallographic anisotropy dictates defect dynamics,offering atomic-scale insights into deformation twinning and transient phase transitions.This work bridges atomistic processes to macroscopic properties,advancing the design of next-generation lightweight hightemperature materials.
基金supported by the National Natural Science Foundation of China(grant nos.31921005 and 31991211)the Strategic Priority Research Program of the Chinese Academy of Sciences(grant nos.XDA24010104,XDA24010204,and XDA24030102)+1 种基金the Special Information Program of the Chinese Academy of Sciences(grant no.XXH13506-408)the China Agricultural Research System(grant no.CARS-03).
文摘Studying the regulatory mechanisms that drive nitrogen-use efficiency(NUE)in crops is important for sustainable agriculture and environmental protection.In this study,we generated a high-quality genome assembly for the high-NUE wheat cultivar Kenong 9204 and systematically analyzed genes related to nitrogen uptake and metabolism.By comparative analyses,we found that the high-affinity nitrate transporter gene family had expanded in Triticeae.Further studies showed that subsequent functional differentiation endowed the expanded family members with saline inducibility,providing a genetic basis for improving the adaptability of wheat to nitrogen deficiency in various habitats.To explore the genetic and molecular mechanisms of high NUE,we compared genomic and transcriptomic data from the high-NUE cultivar Kenong 9204(KN9204)and the low-NUE cultivar Jing 411 and quantified their nitrogen accumulation under high-and low-nitrogen conditions.Compared with Jing 411,KN9204 absorbed significantly more nitrogen at the reproductive stage after shooting and accumulated it in the shoots and seeds.Transcriptome data analysis revealed that nitrogen deficiency clearly suppressed the expression of genes related to cell division in the young spike of Jing 411,whereas this suppression of gene expression was much lower in KN9204.In addition,KN9204 maintained relatively high expression of NPF genes for a longer time than Jing 411 during seed maturity.Physiological and transcriptome data revealed that KN9204 was more tolerant of nitrogen deficiency than Jing 411,especially at the reproductive stage.The high NUE of KN9204 is an integrated effect controlled at different levels.Taken together,our data provide new insights into the molecular mechanisms of NUE and important gene resources for improving wheat cultivars with a higher NUE trait.
