The strength-ductility trade-off in magnesium alloys remains a critical challenge urgently requiring resolution in their engineering applications.In this study,both mechanical and corrosion properties are enhanced in ...The strength-ductility trade-off in magnesium alloys remains a critical challenge urgently requiring resolution in their engineering applications.In this study,both mechanical and corrosion properties are enhanced in extruded Mg-Y-Nd-Zr alloys by Sm addition.Sm promotes dynamic recrystallization,activates non-basal slip systems and weakens basal texture intensity,leading to the sub-grain lamellar structure and rare earth texture.The EWS2 alloy exhibits an outstanding combination of high yield strength(328 MPa)and ductility(15.1%).Furthermore,the fragmented second phases in the Sm-containing alloy are uniformly distributed,reducing the subsequent corrosion driving force after micro-galvanic corrosion and facilitating the growth of a more passivating and compact corrosion film.These combined effects contribute to the lowest degradation rate in the EWS2 alloy.This study demonstrates the correlation between microstructure and properties in Sm-containing WE series alloys,providing insights for the design of other high performance magnesium alloys.展开更多
To address the issues of high costs and low component utilization caused by the independent configuration of hybrid DC circuit breakers(HCBs)and DC power flow controllers(DCPFCs)at each port in existing DC distributio...To address the issues of high costs and low component utilization caused by the independent configuration of hybrid DC circuit breakers(HCBs)and DC power flow controllers(DCPFCs)at each port in existing DC distribution networks,this paper adopts a component sharing mechanism to propose a composite multi-port hybrid DC circuit breaker(CM-HCB)with DC power flow and fault current limitation abilities,as well as reduced component costs.The proposed CM-HCB topology enables the sharing of the main breaker branch(MB)and the energy dissipation branch,while the load commutation switches(LCSs)in the main branch are reused as power flow control components,enabling flexible regulation of power flow in multiple lines.Meanwhile,by reconstructing the current path during the fault process,the proposed CM-HCB can utilize the internal coupled inductor to limit the current rise rate at the initial stage of the fault,significantly reducing the requirement for breaking current.A detailed study on the topological structure,steady-state power flow regulation mechanism,transient fault isolation mechanism,control strategy and characteristic analysis of the proposed CM-HCB is presented.Then,a Matlab/Simulink-based meshed three-terminal DC grid simulation platform with the proposed CM-HCB is built.The results indicate that the proposed CM-HCB can not only achieve flexible power flow control during steady-state operation,but also obtain current rise limitation and fault isolation abilities under short-circuit fault conditions,verifying its correctness and effectiveness.Finally,a comparative economic analysis is conducted between the proposed CM-HCB and the other two existing solutions,confirming that its component sharing mechanism can significantly reduce the number of components,lower system costs,and improve component utilization.展开更多
The hot deformation behavior of magnesium(Mg)alloys is significantly governed by the multi-physics coupling effects of temperature(T),strain rate(ε)and strain(ε),resulting in flow behavior that exhibits pronounced n...The hot deformation behavior of magnesium(Mg)alloys is significantly governed by the multi-physics coupling effects of temperature(T),strain rate(ε)and strain(ε),resulting in flow behavior that exhibits pronounced nonlinearity and multi-scale complexity.This study systematically investigates the hot deformation behavior of Mg-Y-Nd-(Sm)-Zr alloys.Sm alloying promotes recrystallization.The flow stress of Sm-containing alloys declines sharply towards a steady state after reaching its peak value.To overcome the limitations of the Arrhenius-type constitutive(AC)model in predicting complex nonlinear flow behavior,the AC and data hybrid informed neural network(ACINN)model is developed.This approach enhances the predictive accuracy and extends the applicability of the traditional AC model.The evolution of microstructure and recrystallization behavior under hot deformation conditions are investigated based on results from electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM).The relationship between the power dissipation factor(η)and recrystallization behavior is further examined using K-means clustering analysis.The results demonstrate that dynamic recrystallization(DRX)behavior varies with theηvalue,comprising four distinct regimes:dynamic recovery(DRV),discontinuous dynamic recrystallization(DDRX)dominance,continuous dynamic recrystallization(CDRX)dominance and complete dynamic recrystallization.This analysis presents a new perspective for studying the hot deformation processes of Mg alloys.展开更多
In this study,friction stir processing(FSP)was employed to modify the as-cast Mg-14Gd-0.6Ce-0.5Zr alloy,and the effects of texture evolution and distribution of second phases on mechanical properties were systematical...In this study,friction stir processing(FSP)was employed to modify the as-cast Mg-14Gd-0.6Ce-0.5Zr alloy,and the effects of texture evolution and distribution of second phases on mechanical properties were systematically investigated.The results show that friction stir processing effectively refined the coarse Mg_(5)Gd phases into nanoscale second phases uniformly distributed along grain boundaries.The synergistic effect of texture weakening and second phases refinement significantly enhanced the tensile strength and elongation of the FSP-1000-120 alloy to 302.1 MPa and 18.3%,respectively,representing increases of 20.8%and 281.3%compared to the as-cast alloy.The as-cast alloy has a lower corrosion rate in the initial stage due to fewer micro-galvanic corrosion sites.However,the uniform distribution of the second phase in the FSP-treated(FSPed)alloy contributes to the formation of a more complete and dense corrosion product film.After 120 h of immersion,the as-cast alloy forms deep pits due to the continuous dissolution at the second phase-matrix interface,with the average corrosion rate increasing from 0.31 to 0.47 mL/cm^(2)/h.The long-term corrosion rates of FSP-1000-60,FSP-1000-120,and FSP-1200-120 samples are stable at 0.36,0.43,and 0.50 mL/cm^(2)/h,respectively.Research reveals that FSP regulates texture and second phase distribution to achieve synergistic strengthening of alloy strength plasticity,and the homogenization of second phase distribution is a key factor in improving the long-term corrosion resistance of alloys.展开更多
The dynamic recrystallization(DRX)and dynamic precipitation of Mg-5Gd-3Sm(-1Zn)-0.5Zr alloys after hot compression deformation were analyzed by electron backscatter diffraction(EBSD)and transmission electron microscop...The dynamic recrystallization(DRX)and dynamic precipitation of Mg-5Gd-3Sm(-1Zn)-0.5Zr alloys after hot compression deformation were analyzed by electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM)techniques.Further-more,the DRX mechanisms were investigated by calculating the deformation activation energy,establishing the constitutive equation,and creating a critical strain model.The results indicate that the presence of Zn element enhanced the production of DRX,considerably re-duced the strength of{0001}plane texture,and boosted the Schmidt factor of nonbasal plane slip.The Mg-5Gd-3Sm-0.5Zr alloy had a low degree of DRX,manifested as a monolayer of DRX grains at the grain boundaries,and dominated by the discontinuous DRX mech-anism.However,the Mg-5Gd-3Sm-1Zn-0.5Zr alloy had a high degree of DRX,which occurred in the form of multilayered DRX grains by the main mechanism of continuous DRX.Compared with the Mg-5Gd-3Sm-0.5Zr alloy,in addition to the Mg5(Gd,Sm)phase,the Mg-5Gd-3Sm-1Zn-0.5Zr alloy also introduced a new dynamic precipitation phase called(Mg,Zn)_(3)(Gd,Sm)phase.The dynamic precip-itation phase prevented grain boundary migration and dislocation motion,which promoted DRX nucleation and prevented the growth of recrystallized grains.展开更多
The effect of different extrusion parameters on the microstructure and mechanical properties of Mg-4Sm-3Gd-2Yb-0.5Zr(SGY2)alloy was investigated.It was observed that under different extrusion parameters,unDRXed grains...The effect of different extrusion parameters on the microstructure and mechanical properties of Mg-4Sm-3Gd-2Yb-0.5Zr(SGY2)alloy was investigated.It was observed that under different extrusion parameters,unDRXed grains of SGY2 alloy exhibited a pronounced basal plane texture,specifically<01.10>//ED,while the texture of DRXed grains was relatively dispersed.Under the condition of 420℃ and an extrusion ratio of 9.4(420℃-ER9.4),the basal plane texture intensity of unDRXed grains in SGY2 alloy was the highest.Furthermore,SGY2 alloy at different extrusion parameters exhibited recrystallization mechanisms mainly characterized by continuous dynamic recrystallization(CDRX),with some DRXed grains and deformed grains experiencing discontinuous dynamic recrystallization(DDRX).Additionally,at the 420℃-ER9.4,the second phase particles in the as-extruded SGY2 alloy were smaller in size and exhibited a dispersed distribution.Under this condition,a significant amount of dislocation accumulation,dislocation bypassing,and dislocation tangling phenomena were observed in the SGY2 alloy.The primary deformation mechanism of unDRXed grains in the SGY2 alloy at the 420℃-ER9.4 may involve prismatic plane,pyramidal plane,and pyramidal plane<c+a>slip,thereby activating a significant amount of dislocations.Compared to other extrusion conditions,this condition is more prone to activate non-basal plane slip.The as-extruded SGY2 alloy exhibited superior mechanical properties,with ultimate tensile strength(UTS)and yield strength(YS)of 332 MPa and 278 MPa,respectively.This is mainly attributed to the extremely fine grains,with many DRXed grains having grain sizes smaller than 1μm,and higher density grain boundaries produced under this condition.Additionally,the unDRXed grains contain a high density of dislocations with small Schmid factor(SF),thus effectively inhibiting basal plane slip and strengthening the alloy to some extent.Similarly,the increased presence of second phase particles will also contribute to strengthening the alloy matrix through precipitation hardening.展开更多
A high-strength magnesium alloy containing Yb was prepared through a simple hot extrusion process.The effect of Yb addition on dynamic precipitation,texture evolution,dynamic recrystallization mechanisms,deformation m...A high-strength magnesium alloy containing Yb was prepared through a simple hot extrusion process.The effect of Yb addition on dynamic precipitation,texture evolution,dynamic recrystallization mechanisms,deformation mechanisms,and strengthening mechanisms in as-extruded Mg-4 Sm-3 Gd(-2 Yb)-0.5 Zr(SGY0,SGY2)alloys was systematically investigated.The results indicated that the average grain size decreased from 4.17μm to 1.48μm with the addition of Yb.This extreme grain refinement greatly enhances the strength.The addition of Yb significantly facilitated the phase precipitation,but did not change the texture type.The non-dynamic recrystallized(un DRXed)grains exhibited a strong basal plane texture of<0110>parallel to the extrusion direction(ED),while the dynamic recrystallized(DRXed)grains showed a weaker rare earth texture,characterized by<1212>//ED.Moreover,the as-extruded SGY0 and SGY2 alloys predominantly undergo continuous dynamic recrystallization(CDRX),and some DRXed grains exhibit a discontinuous dynamic recrystallization mechanism(DDRX).In addition,the addition of Yb facilitates the activation of non-basal plane slip.The dislocation types in the as-extruded SGY0 and SGY2 alloys include(a),(c)and(c+a)dislocations.However,the SGY2 alloy exhibits a relatively high dislocation density,which contributes to the enhancement of the strength.Extreme grain refinement and the dispersion of nanoscale second-phase particles are key factors in increasing the strength.展开更多
Objective: This analysis was conducted to clarify risk factors for chemotherapy-induced leukopenia (CIL) in lung cancer. Methods: A retrospective study was conducted on data from 358 patients with lung cancer who rece...Objective: This analysis was conducted to clarify risk factors for chemotherapy-induced leukopenia (CIL) in lung cancer. Methods: A retrospective study was conducted on data from 358 patients with lung cancer who received chemotherapy. Results: Among 358 cases of lung cancer who received chemotherapy, a total of 240 patients experienced CIL, rate was 67%. The demographic data including gender (P = 0.795), age (P = 0.134), presence of selected chronic comorbidities (P = 0.23) were not significantly different in the two groups. The weight loss rate, PS score, sub-normal pre-WBC level, sub-normal pre-PLT level, and the cycle of chemotherapy were significantly different between the groups (P < 0.05). Multivariate analysis revealed that the weight loss rate ≥5% (OR = 0.503), sub-normal pre-WBC level (OR = 11.807), the cycle of chemotherapy ≥3 (OR = 3.100) were main risk factors for CIL in lung cancer. Conclusion: Before treatment, weight loss rate is 5% or higher, chemotherapy has a cycle of 3 or more and sub-normal WBC level is independent risk factor of lung cancer after chemotherapy-induced leucopenia.展开更多
The effects of Sm on the microstructure and mechanical properties of Mg-11 Gd-2 Y-0.6 Al alloy were investigated by X-ray diffraction,optical microscopy,scanning electron microscopy,energy dispersive spectrometry and ...The effects of Sm on the microstructure and mechanical properties of Mg-11 Gd-2 Y-0.6 Al alloy were investigated by X-ray diffraction,optical microscopy,scanning electron microscopy,energy dispersive spectrometry and high resolution transmission electron microscopy.Based on the theory of edge—edge matching and electronegativity theory,the mechanism of grain refinement is discussed.The strengthening mechanism is expounded conveniently from fine grain strengthening,coherent strengthening,precipitation strengthening and grain boundary strengthening.The results show that the micro structure of Mg-11 Gd-2 Y-0.6 Al alloy is mainly composed of a-Mg matrix,Mg5 Gd and Mg24Y5 phases.The addition of Sm forms Mg41Sm5 phase in the alloy and refines the alloy.The addition of Sm significantly improves the mechanical properties of the alloy at room and high temperatures.When the addition of Sm is 3 wt%,the tensile strengths of the alloy at room temperature and high temperature(200℃)reach the maximum value 292 and 321 MPa,respectively.The fracture mode of the alloy at different temperatures is mainly brittle fracture and intercrystalline fracture.展开更多
Tdmercaptotriazine-functionalized polystyrene chelating resin was prepared and employed for the adsorption of Ag（I） from aqueous solution. The adsorbent was characterized according to the following techniques： Four...Tdmercaptotriazine-functionalized polystyrene chelating resin was prepared and employed for the adsorption of Ag（I） from aqueous solution. The adsorbent was characterized according to the following techniques： Fourier transform infrared spectroscopy, elemental analysis, scanning electron microscopy and the Brunauer-Emmet-Teller method. The effects of initial Ag（I） concentration, contact time, solution pH and coexisting ions on the adsorption capacity of Ag（I） were systematically investigated. The maximum adsorption capacity of AgO） was up to 187.1 mg/g resin at pH 0.0 and room temperature. The kinetic experiments indicated that the adsorption rate of Ag（I） onto the chelating resin was quite fast in the first 60 rain and reached adsorption equilibrium after 360 min. The adsorption process can be well described by the pseudo second-order kinetic model and the equilibrium adsorption isotherm was closely fitted by the Langmuir model. Moreover, the chelating resin could selectively adsorb more Ag（I） ions than other heavy metal ions including： Cu（Ⅱ）, Zn（Ⅱ）, Ni（Ⅱ）, Pb（Ⅱ） and Cr（Ⅲ） during competitive adsorption in the binary metal species systems, which indicated that it was a highly selective adsorbent of Ag（I） from aqueous solution.展开更多
FeCe nanocomposite catalysts with different iron contents were synthesized by a facile co-precipitation method.The as-prepared materials were characterized by various techniques including powder X-ray diffraction(XRD)...FeCe nanocomposite catalysts with different iron contents were synthesized by a facile co-precipitation method.The as-prepared materials were characterized by various techniques including powder X-ray diffraction(XRD),N2 adsorption/desorption and high-resolution transmission electron microscopy(HRTEM).Catalyst with the highest iron content(90 FeCe) shows the best activity for the hydrogen generation via ammonia decomposition.83% NH3 conversion is achieved at 550℃ and nearly full conversion of NH3 is realized at 600℃ with a GHSV of 24000 cm3/(gcat·h).The large content and small size crystal particles of iron species are responsible for the good catalytic performance.Temperatureprogrammed reduction by hydrogen(H2-TPR) was performed to investigate the interaction between cerium and iron species.It is found that slight cerium can exert strong interaction with iron compound thus effectively prevent the self-aggregation of active iron species,so as to improve the catalytic activity for ammonia decomposition.展开更多
The thermal decomposition process was studied by the TG–DTA analyzer. The results show that the decomposition process of sodium hydroxyethyl sulfonate consisted of three stages: the mass loss for the first, the secon...The thermal decomposition process was studied by the TG–DTA analyzer. The results show that the decomposition process of sodium hydroxyethyl sulfonate consisted of three stages: the mass loss for the first, the second and third stages may be about the groups of CH_3CH_2OH, CH_3CHO and SO_2 volatilized, respectively. The decomposition residuum of three stages was analyzed by FT-IR, and the results of FT-IR agreed with the decomposition process predicted by theoretical weight loss. The specific heat capacity of sodium hydroxyethyl sulfonate was determined by differential scanning calorimetry(DSC). The melting temperature and melting enthalpy were obtained to be 465.41 K and 25.69 kJ·mol^(-1), respectively. The molar specific heat capacity of sodium hydroxyethyl sulfonate was determinated from 310.15 K to 365.15 K and expressed as a function of temperature.展开更多
S Background Music therapy is a promising complementary intervention for addressing various mental health conditions.Despite evidence of the beneficial effects of music,the acoustic features that make music effective ...S Background Music therapy is a promising complementary intervention for addressing various mental health conditions.Despite evidence of the beneficial effects of music,the acoustic features that make music effective in therapeutic contexts remain elusive.Aims This study aimed to identify and validate distinctive acoustic features of healing music.Methods We constructed a healing music dataset(HMD)based on nominations from related professionals and extracted 370 acoustic features.Healing-distinctive acoustic features were identified as those that were(1)independent from genre within the HMD,(2)significantly different from music pieces in a classical music dataset(CMD)and(3)similar to pieces in a five-element music dataset(FEMD).We validated the identified features by comparing jazz pieces in the HMD with a jazz music dataset(JMD).We also examined the emotional properties of the features in a Chinese affective music system(CAMS).Results The HMD comprised 165 pieces.Among all the acoustic features,74.59%shared commonalities across genres,and 26.22%significantly differed between the HMD classical pieces and the CMD.The equivalence test showed that the HMD and FEMD did not differ significantly in 9.46%of the features.The potential healing-distinctive acoustic features were identified as the standard deviation of the roughness,mean and period entropy of the third coefficient of the mel-frequency cepstral coefficients.In a three-dimensional space defined by these features,HMD's jazz pieces could be distinguished from those of the JMD.These three features could significantly predict both subjective valence and arousal ratings in the CAMS.Conclusions The distinctive acoustic features of healing music that have been identified and validated in this study have implications for the development of artificial intelligence models for identifying therapeutic music,particularly in contexts where access to professional expertise may be limited.This study contributes to the growing body of research exploring the potential of digital technologies for healthcare interventions.展开更多
Plants are amazing chemical factories,and medicinal plants provide a myriad of pharmaceutically active compounds that have been commonly used as traditional medicines for thousands of years.The practice of traditional...Plants are amazing chemical factories,and medicinal plants provide a myriad of pharmaceutically active compounds that have been commonly used as traditional medicines for thousands of years.The practice of traditional medicine in China dates back at least 4,500 years.The Shen Nong Ben Cao Jing("Shen Nong's Herbal Classic"in 770−475 BC)has been considered the oldest list of medicinal plants.Recent rapid economic development has enabled China to invest substantially in science and technology research.In many ethnic groups worldwide,herbal medicines are,in the same way as traditional Chinese medicines,still commonly used today.A wide array of plant-extract health supplements has become increasingly popular in Western societies.Numerous drugs derived from a broad range of plant species have been discoveried,such as taxol and artemisinin and their derivatives.展开更多
Biosafety is essential to ensuring the safe and effective conduct of biological research by minimizing risks associated with laboratory work and biological materials.This paper traces the historical and conceptual dev...Biosafety is essential to ensuring the safe and effective conduct of biological research by minimizing risks associated with laboratory work and biological materials.This paper traces the historical and conceptual development of biosafety,from its origins in pathogen containment to its expansion into broader domains.In the modern context,biosafety also involves the regulation of genetically modified organisms and the strengthening of laboratory oversight mechanisms.Biosafety and biosecurity are closely related in origin.Biosafety focuses on biological risks within laboratory environments,while biosecurity addresses biological risks associated with non-laboratory environments.The article summarizes the development of biosafety,extracting the evolution of its conceptual framework from a historical perspective,condenses and compares its scientific characteristics with those of biosecurity,and applies the methodology of science history to define its conceptual framework.展开更多
Virology,as a branch of microbiology,is a science that studies viruses,covering various aspects of their life activities,such as types,composition,structure,metabolism,growth,reproduction,genetics,evolution,and distri...Virology,as a branch of microbiology,is a science that studies viruses,covering various aspects of their life activities,such as types,composition,structure,metabolism,growth,reproduction,genetics,evolution,and distribution,as well as their interactions with other organisms and the environment(Flint et al.,2015;Zuo et al.,2024).The scope of virology research is broad,encompassing virus classification,pathogenic mechanisms,genomics,vaccine development,immunology,diagnostics,and virology education and talent training.Significant progress in virology research has greatly promoted advancements in medicine,agriculture,and public health.展开更多
目的探讨3.0 T MRI的定量磁敏感成像(QSM)上中央静脉征(CVS)、铁沉积鉴别诊断多发性硬化(MS)与视神经脊髓炎谱系疾病(NMOSD)患者颅内病灶的价值。方法本研究为回顾性研究。收集2018年7月至2020年12月乐山市人民医院和重庆医科大学附属...目的探讨3.0 T MRI的定量磁敏感成像(QSM)上中央静脉征(CVS)、铁沉积鉴别诊断多发性硬化(MS)与视神经脊髓炎谱系疾病(NMOSD)患者颅内病灶的价值。方法本研究为回顾性研究。收集2018年7月至2020年12月乐山市人民医院和重庆医科大学附属第一医院临床确诊的54例MS患者和49例NMOSD患者。所有患者均接受常规MRI和三维增强T2*加权血管成像(3D-ESWAN),并从3D-ESWAN数据重建滤波相位图和QSM。首先在质子密度(PD)-T2WI筛选MS及NMOSD的颅内病灶,然后在相位图和QSM图上观察病灶位置、CVS以及结节状、环状铁沉积。采用χ^(2)检验比较MS与NMOSD患者颅内病灶位置、CVS、铁沉积的差异。采用受试者操作特征曲线及曲线下面积(AUC)评估CVS、QSM铁沉积鉴别MS和NMOSD的效能。结果 54例MS患者观察到968个颅脑病灶,其中354个病灶有CVS,227个CVS位于侧脑室周围,117个位于深部白质(DWM),10个位于皮层/皮层下;QSM上有372个病灶表现为结节状铁沉积、193个病灶表现为环状铁沉积。48例NMOSD患者中41例观察到247个颅脑病灶,其中4个病灶有CVS,1个位于侧脑室周围,3个位于DWM;QSM上3个病灶有结节状铁沉积。MS与NMOSD患者颅内病灶位于皮层/皮层下、CVS、铁沉积差异有统计学意义(χ^(2)分别为29.33、115.66、258.21,P<0.001)。CVS鉴别MS和NMOSD的AUC为0.941(95%CI 0.887~0.994),灵敏度为96.3%,特异度为91.8%;铁沉积鉴别MS和NMOSD的AUC为0.969(95%CI 0.930~1.000),灵敏度为100%,特异度为93.9%。结论 3.0 T MRI上CVS和铁沉积是MS病灶截然不同于NMOSD病灶的影像学特征,对鉴别二者具有一定的价值。展开更多
Cotton is an irreplaceable economic crop currently domesticated in the human world for its extremely elongated fiber cells specialized in seed epidermis,which makes it of high research and application value.To date,nu...Cotton is an irreplaceable economic crop currently domesticated in the human world for its extremely elongated fiber cells specialized in seed epidermis,which makes it of high research and application value.To date,numerous research on cotton has navigated various aspects,from multi-genome assembly,genome editing,mechanism of fiber development,metabolite biosynthesis,and analysis to genetic breeding.Genomic and 3D genomic studies reveal the origin of cotton species and the spatiotemporal asymmetric chromatin structure in fibers.Mature multiple genome editing systems,such as CRISPR/Cas9,Cas12(Cpf1)and cytidine base editing(CBE),have been widely used in the study of candidate genes affecting fiber development.Based on this,the cotton fiber cell development network has been preliminarily drawn.Among them,the MYB-b HLH-WDR(MBW)transcription factor complex and IAA and BR signaling pathway regulate the initiation;various plant hormones,including ethylene,mediated regulatory network and membrane protein overlap fine-regulate elongation.Multistage transcription factors targeting Ces A 4,7,and 8 specifically dominate the whole process of secondary cell wall thickening.And fluorescently labeled cytoskeletal proteins can observe real-time dynamic changes in fiber development.Furthermore,research on the synthesis of cotton secondary metabolite gossypol,resistance to diseases and insect pests,plant architecture regulation,and seed oil utilization are all conducive to finding more high-quality breeding-related genes and subsequently facilitating the cultivation of better cotton varieties.This review summarizes the paramount research achievements in cotton molecular biology over the last few decades from the above aspects,thereby enabling us to conduct a status review on the current studies of cotton and provide strong theoretical support for the future direction.展开更多
The overuse of antibiotics in animal agriculture and medicine has caused a series of potential threats to public health. Macleaya cordata is a medicinal plant species from the Papaveraceae family, providing a safe res...The overuse of antibiotics in animal agriculture and medicine has caused a series of potential threats to public health. Macleaya cordata is a medicinal plant species from the Papaveraceae family, providing a safe resource for the manufacture of antimicrobial feed additive for livestock. The active constituents from M. cordata are known to include benzylisoquinoline alkaloids （BIAs） such as sanguinarine （SAN） and chelerythrine （CHE）, but their metabolic pathways have yet to be studied in this non-model plant. The active biosynthesis of SAN and CHE in M. cordata was first examined and confirmed by feeding ^13C-labeled tyrosine. To gain further insights, we de novo sequenced the whole genome of M. cordata, the first to be sequenced from the Papaveraceae family. The M. cordata genome covering 378 Mb encodes 22,328 predicted protein-coding genes with 43.5% being transposable elements. As a member of basal eudicot, M. cordata genome lacks the paleohexaploidy event that occurred in almost all eudicots. From the genomics data, a complete set of 16 metabolic genes for SAN and CHE biosynthesis was retrieved, and 14 of their biochemical activities were validated. These genomics and metabolic data show the conserved BIA metabolic pathways in M. cordata and provide the knowledge foundation for future productions of SAN and CHE by crop improvement or microbial pathway reconstruction.展开更多
Sesquiterpenoids are a class of 15-carbon secondary metabolites that play diverse roles in plant adaptation to environment. Cotton plants accumulate a large amount of sesquiterpene aldehydes （including gossypol） as ...Sesquiterpenoids are a class of 15-carbon secondary metabolites that play diverse roles in plant adaptation to environment. Cotton plants accumulate a large amount of sesquiterpene aldehydes （including gossypol） as phytoalexins against pathogens and herbivores. They are stored in pigment glands of aerial organs and in epidermal layers of roots. Several enzymes of goss- ypol biosynthesis pathway have been characterized, including 3-hydroxy-3-methylglutaryl coenzyme A reductase （HMGR） and farnesyl diphosphate synthase （FPS） that catalyze the formation of the precursor farnesyl diphosphate （FPP）, （＋）-6-cadinene synthase （CDN） which is the first enzyme committed to gossypol biosynthesis, and the downstream enzymes of CYP706B 1 and methyltransferase. Expressions of these genes are tightly regulated during cotton plants development and in- duced by jasmonate and fungi elicitors. The transcription factor GaWRKY1 has been shown to be involved in gossypol path- way regulation. Recent development of new genomic platforms and methods and releases of diploid and tetraploid cotton ge- nome sequences will greatly facilitate the elucidation of gossypol biosynthetic pathway and its regulation.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52201119,52371108)Frontier Exploration Project of Longmen Laboratory,China(No.LMQYTSKT014)The Joint Fund of Henan Science and Technology R&D Plan of China(No.242103810056).
文摘The strength-ductility trade-off in magnesium alloys remains a critical challenge urgently requiring resolution in their engineering applications.In this study,both mechanical and corrosion properties are enhanced in extruded Mg-Y-Nd-Zr alloys by Sm addition.Sm promotes dynamic recrystallization,activates non-basal slip systems and weakens basal texture intensity,leading to the sub-grain lamellar structure and rare earth texture.The EWS2 alloy exhibits an outstanding combination of high yield strength(328 MPa)and ductility(15.1%).Furthermore,the fragmented second phases in the Sm-containing alloy are uniformly distributed,reducing the subsequent corrosion driving force after micro-galvanic corrosion and facilitating the growth of a more passivating and compact corrosion film.These combined effects contribute to the lowest degradation rate in the EWS2 alloy.This study demonstrates the correlation between microstructure and properties in Sm-containing WE series alloys,providing insights for the design of other high performance magnesium alloys.
基金funded by Youth Talent Growth Project of Guizhou Provincial Department of Education(No.Qianjiaoji[2024]21)National Natural Science Foundation of China(No.62461008 and No.52507211)Guizhou Provincial Key Technology R&D Program(No.[2024]General 049).
文摘To address the issues of high costs and low component utilization caused by the independent configuration of hybrid DC circuit breakers(HCBs)and DC power flow controllers(DCPFCs)at each port in existing DC distribution networks,this paper adopts a component sharing mechanism to propose a composite multi-port hybrid DC circuit breaker(CM-HCB)with DC power flow and fault current limitation abilities,as well as reduced component costs.The proposed CM-HCB topology enables the sharing of the main breaker branch(MB)and the energy dissipation branch,while the load commutation switches(LCSs)in the main branch are reused as power flow control components,enabling flexible regulation of power flow in multiple lines.Meanwhile,by reconstructing the current path during the fault process,the proposed CM-HCB can utilize the internal coupled inductor to limit the current rise rate at the initial stage of the fault,significantly reducing the requirement for breaking current.A detailed study on the topological structure,steady-state power flow regulation mechanism,transient fault isolation mechanism,control strategy and characteristic analysis of the proposed CM-HCB is presented.Then,a Matlab/Simulink-based meshed three-terminal DC grid simulation platform with the proposed CM-HCB is built.The results indicate that the proposed CM-HCB can not only achieve flexible power flow control during steady-state operation,but also obtain current rise limitation and fault isolation abilities under short-circuit fault conditions,verifying its correctness and effectiveness.Finally,a comparative economic analysis is conducted between the proposed CM-HCB and the other two existing solutions,confirming that its component sharing mechanism can significantly reduce the number of components,lower system costs,and improve component utilization.
基金supported by the National Natural Science Foundation of China(nos.52201119,52371108)Frontier Exploration Project of Longmen Laboratory,China(no.LMQYTSKT014)The Joint Fund of Henan Science and Technology R&D Plan of China(no.242103810056).
文摘The hot deformation behavior of magnesium(Mg)alloys is significantly governed by the multi-physics coupling effects of temperature(T),strain rate(ε)and strain(ε),resulting in flow behavior that exhibits pronounced nonlinearity and multi-scale complexity.This study systematically investigates the hot deformation behavior of Mg-Y-Nd-(Sm)-Zr alloys.Sm alloying promotes recrystallization.The flow stress of Sm-containing alloys declines sharply towards a steady state after reaching its peak value.To overcome the limitations of the Arrhenius-type constitutive(AC)model in predicting complex nonlinear flow behavior,the AC and data hybrid informed neural network(ACINN)model is developed.This approach enhances the predictive accuracy and extends the applicability of the traditional AC model.The evolution of microstructure and recrystallization behavior under hot deformation conditions are investigated based on results from electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM).The relationship between the power dissipation factor(η)and recrystallization behavior is further examined using K-means clustering analysis.The results demonstrate that dynamic recrystallization(DRX)behavior varies with theηvalue,comprising four distinct regimes:dynamic recovery(DRV),discontinuous dynamic recrystallization(DDRX)dominance,continuous dynamic recrystallization(CDRX)dominance and complete dynamic recrystallization.This analysis presents a new perspective for studying the hot deformation processes of Mg alloys.
基金supported by the National Natural Science Foundation of China(Nos.52201119,52371108,52203295)the Joint Fund of Henan Science and Technology R&D Plan of China(242103810056)Frontier Exploration Project of Longmen Laboratory,China(LMQYTSKT014).
文摘In this study,friction stir processing(FSP)was employed to modify the as-cast Mg-14Gd-0.6Ce-0.5Zr alloy,and the effects of texture evolution and distribution of second phases on mechanical properties were systematically investigated.The results show that friction stir processing effectively refined the coarse Mg_(5)Gd phases into nanoscale second phases uniformly distributed along grain boundaries.The synergistic effect of texture weakening and second phases refinement significantly enhanced the tensile strength and elongation of the FSP-1000-120 alloy to 302.1 MPa and 18.3%,respectively,representing increases of 20.8%and 281.3%compared to the as-cast alloy.The as-cast alloy has a lower corrosion rate in the initial stage due to fewer micro-galvanic corrosion sites.However,the uniform distribution of the second phase in the FSP-treated(FSPed)alloy contributes to the formation of a more complete and dense corrosion product film.After 120 h of immersion,the as-cast alloy forms deep pits due to the continuous dissolution at the second phase-matrix interface,with the average corrosion rate increasing from 0.31 to 0.47 mL/cm^(2)/h.The long-term corrosion rates of FSP-1000-60,FSP-1000-120,and FSP-1200-120 samples are stable at 0.36,0.43,and 0.50 mL/cm^(2)/h,respectively.Research reveals that FSP regulates texture and second phase distribution to achieve synergistic strengthening of alloy strength plasticity,and the homogenization of second phase distribution is a key factor in improving the long-term corrosion resistance of alloys.
基金supported by the National Natural Science Foundation of China(Nos.52201119 and 52371108)the Frontier Exploration Project of Longmen Laboratory,China(No.LMQYTSKT014)the 12th Postgraduate Innovation Fund of Henan University of Science and Technology(No.CXJJ-2023-KJ04).
文摘The dynamic recrystallization(DRX)and dynamic precipitation of Mg-5Gd-3Sm(-1Zn)-0.5Zr alloys after hot compression deformation were analyzed by electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM)techniques.Further-more,the DRX mechanisms were investigated by calculating the deformation activation energy,establishing the constitutive equation,and creating a critical strain model.The results indicate that the presence of Zn element enhanced the production of DRX,considerably re-duced the strength of{0001}plane texture,and boosted the Schmidt factor of nonbasal plane slip.The Mg-5Gd-3Sm-0.5Zr alloy had a low degree of DRX,manifested as a monolayer of DRX grains at the grain boundaries,and dominated by the discontinuous DRX mech-anism.However,the Mg-5Gd-3Sm-1Zn-0.5Zr alloy had a high degree of DRX,which occurred in the form of multilayered DRX grains by the main mechanism of continuous DRX.Compared with the Mg-5Gd-3Sm-0.5Zr alloy,in addition to the Mg5(Gd,Sm)phase,the Mg-5Gd-3Sm-1Zn-0.5Zr alloy also introduced a new dynamic precipitation phase called(Mg,Zn)_(3)(Gd,Sm)phase.The dynamic precip-itation phase prevented grain boundary migration and dislocation motion,which promoted DRX nucleation and prevented the growth of recrystallized grains.
基金financially supported by the National Natural Science Foundation of China(No.52371108,52201119)Frontier Exploration Project of Longmen Laboratory,China(LMQYTSKT014).
文摘The effect of different extrusion parameters on the microstructure and mechanical properties of Mg-4Sm-3Gd-2Yb-0.5Zr(SGY2)alloy was investigated.It was observed that under different extrusion parameters,unDRXed grains of SGY2 alloy exhibited a pronounced basal plane texture,specifically<01.10>//ED,while the texture of DRXed grains was relatively dispersed.Under the condition of 420℃ and an extrusion ratio of 9.4(420℃-ER9.4),the basal plane texture intensity of unDRXed grains in SGY2 alloy was the highest.Furthermore,SGY2 alloy at different extrusion parameters exhibited recrystallization mechanisms mainly characterized by continuous dynamic recrystallization(CDRX),with some DRXed grains and deformed grains experiencing discontinuous dynamic recrystallization(DDRX).Additionally,at the 420℃-ER9.4,the second phase particles in the as-extruded SGY2 alloy were smaller in size and exhibited a dispersed distribution.Under this condition,a significant amount of dislocation accumulation,dislocation bypassing,and dislocation tangling phenomena were observed in the SGY2 alloy.The primary deformation mechanism of unDRXed grains in the SGY2 alloy at the 420℃-ER9.4 may involve prismatic plane,pyramidal plane,and pyramidal plane<c+a>slip,thereby activating a significant amount of dislocations.Compared to other extrusion conditions,this condition is more prone to activate non-basal plane slip.The as-extruded SGY2 alloy exhibited superior mechanical properties,with ultimate tensile strength(UTS)and yield strength(YS)of 332 MPa and 278 MPa,respectively.This is mainly attributed to the extremely fine grains,with many DRXed grains having grain sizes smaller than 1μm,and higher density grain boundaries produced under this condition.Additionally,the unDRXed grains contain a high density of dislocations with small Schmid factor(SF),thus effectively inhibiting basal plane slip and strengthening the alloy to some extent.Similarly,the increased presence of second phase particles will also contribute to strengthening the alloy matrix through precipitation hardening.
基金financially supported by the National Natural Science Foundation of China(No.52371108,52201119,52203295)Frontier Exploration Project of Longmen Laboratory,China(LMQYTSKT014)the Joint Fund of Henan Science and Technology R&D Plan of China(242103810056)。
文摘A high-strength magnesium alloy containing Yb was prepared through a simple hot extrusion process.The effect of Yb addition on dynamic precipitation,texture evolution,dynamic recrystallization mechanisms,deformation mechanisms,and strengthening mechanisms in as-extruded Mg-4 Sm-3 Gd(-2 Yb)-0.5 Zr(SGY0,SGY2)alloys was systematically investigated.The results indicated that the average grain size decreased from 4.17μm to 1.48μm with the addition of Yb.This extreme grain refinement greatly enhances the strength.The addition of Yb significantly facilitated the phase precipitation,but did not change the texture type.The non-dynamic recrystallized(un DRXed)grains exhibited a strong basal plane texture of<0110>parallel to the extrusion direction(ED),while the dynamic recrystallized(DRXed)grains showed a weaker rare earth texture,characterized by<1212>//ED.Moreover,the as-extruded SGY0 and SGY2 alloys predominantly undergo continuous dynamic recrystallization(CDRX),and some DRXed grains exhibit a discontinuous dynamic recrystallization mechanism(DDRX).In addition,the addition of Yb facilitates the activation of non-basal plane slip.The dislocation types in the as-extruded SGY0 and SGY2 alloys include(a),(c)and(c+a)dislocations.However,the SGY2 alloy exhibits a relatively high dislocation density,which contributes to the enhancement of the strength.Extreme grain refinement and the dispersion of nanoscale second-phase particles are key factors in increasing the strength.
文摘Objective: This analysis was conducted to clarify risk factors for chemotherapy-induced leukopenia (CIL) in lung cancer. Methods: A retrospective study was conducted on data from 358 patients with lung cancer who received chemotherapy. Results: Among 358 cases of lung cancer who received chemotherapy, a total of 240 patients experienced CIL, rate was 67%. The demographic data including gender (P = 0.795), age (P = 0.134), presence of selected chronic comorbidities (P = 0.23) were not significantly different in the two groups. The weight loss rate, PS score, sub-normal pre-WBC level, sub-normal pre-PLT level, and the cycle of chemotherapy were significantly different between the groups (P < 0.05). Multivariate analysis revealed that the weight loss rate ≥5% (OR = 0.503), sub-normal pre-WBC level (OR = 11.807), the cycle of chemotherapy ≥3 (OR = 3.100) were main risk factors for CIL in lung cancer. Conclusion: Before treatment, weight loss rate is 5% or higher, chemotherapy has a cycle of 3 or more and sub-normal WBC level is independent risk factor of lung cancer after chemotherapy-induced leucopenia.
基金Project supported by the National Natural Science Foundation of China(51571084 and 51171059)Project of Scientific And Technological Research In Henan Province(152102210072)
文摘The effects of Sm on the microstructure and mechanical properties of Mg-11 Gd-2 Y-0.6 Al alloy were investigated by X-ray diffraction,optical microscopy,scanning electron microscopy,energy dispersive spectrometry and high resolution transmission electron microscopy.Based on the theory of edge—edge matching and electronegativity theory,the mechanism of grain refinement is discussed.The strengthening mechanism is expounded conveniently from fine grain strengthening,coherent strengthening,precipitation strengthening and grain boundary strengthening.The results show that the micro structure of Mg-11 Gd-2 Y-0.6 Al alloy is mainly composed of a-Mg matrix,Mg5 Gd and Mg24Y5 phases.The addition of Sm forms Mg41Sm5 phase in the alloy and refines the alloy.The addition of Sm significantly improves the mechanical properties of the alloy at room and high temperatures.When the addition of Sm is 3 wt%,the tensile strengths of the alloy at room temperature and high temperature(200℃)reach the maximum value 292 and 321 MPa,respectively.The fracture mode of the alloy at different temperatures is mainly brittle fracture and intercrystalline fracture.
基金supported by the Chinese Academy of Science and Technology Project in Support of Gansu (No.XBLZ-2011-013)
文摘Tdmercaptotriazine-functionalized polystyrene chelating resin was prepared and employed for the adsorption of Ag（I） from aqueous solution. The adsorbent was characterized according to the following techniques： Fourier transform infrared spectroscopy, elemental analysis, scanning electron microscopy and the Brunauer-Emmet-Teller method. The effects of initial Ag（I） concentration, contact time, solution pH and coexisting ions on the adsorption capacity of Ag（I） were systematically investigated. The maximum adsorption capacity of AgO） was up to 187.1 mg/g resin at pH 0.0 and room temperature. The kinetic experiments indicated that the adsorption rate of Ag（I） onto the chelating resin was quite fast in the first 60 rain and reached adsorption equilibrium after 360 min. The adsorption process can be well described by the pseudo second-order kinetic model and the equilibrium adsorption isotherm was closely fitted by the Langmuir model. Moreover, the chelating resin could selectively adsorb more Ag（I） ions than other heavy metal ions including： Cu（Ⅱ）, Zn（Ⅱ）, Ni（Ⅱ）, Pb（Ⅱ） and Cr（Ⅲ） during competitive adsorption in the binary metal species systems, which indicated that it was a highly selective adsorbent of Ag（I） from aqueous solution.
基金Project supported by the Natural Science Foundation of Jiangsu Province (BK20170232,BK20170238)National Natural Science Foundation of China (51908256)。
文摘FeCe nanocomposite catalysts with different iron contents were synthesized by a facile co-precipitation method.The as-prepared materials were characterized by various techniques including powder X-ray diffraction(XRD),N2 adsorption/desorption and high-resolution transmission electron microscopy(HRTEM).Catalyst with the highest iron content(90 FeCe) shows the best activity for the hydrogen generation via ammonia decomposition.83% NH3 conversion is achieved at 550℃ and nearly full conversion of NH3 is realized at 600℃ with a GHSV of 24000 cm3/(gcat·h).The large content and small size crystal particles of iron species are responsible for the good catalytic performance.Temperatureprogrammed reduction by hydrogen(H2-TPR) was performed to investigate the interaction between cerium and iron species.It is found that slight cerium can exert strong interaction with iron compound thus effectively prevent the self-aggregation of active iron species,so as to improve the catalytic activity for ammonia decomposition.
文摘The thermal decomposition process was studied by the TG–DTA analyzer. The results show that the decomposition process of sodium hydroxyethyl sulfonate consisted of three stages: the mass loss for the first, the second and third stages may be about the groups of CH_3CH_2OH, CH_3CHO and SO_2 volatilized, respectively. The decomposition residuum of three stages was analyzed by FT-IR, and the results of FT-IR agreed with the decomposition process predicted by theoretical weight loss. The specific heat capacity of sodium hydroxyethyl sulfonate was determined by differential scanning calorimetry(DSC). The melting temperature and melting enthalpy were obtained to be 465.41 K and 25.69 kJ·mol^(-1), respectively. The molar specific heat capacity of sodium hydroxyethyl sulfonate was determinated from 310.15 K to 365.15 K and expressed as a function of temperature.
基金supported by the National Natural Science Foundation of China(62101324)the Shanghai Sailing Program(20YF1442000)+2 种基金the Academic Leader of the Health Discipline of Shanghai Municipal Health Commission(2022XD025)the Qihang Program of Shanghai Mental Health Center(2020-QH-01)the Hospital Program of Shanghai Mental Health Center(2020-YJ01)。
文摘S Background Music therapy is a promising complementary intervention for addressing various mental health conditions.Despite evidence of the beneficial effects of music,the acoustic features that make music effective in therapeutic contexts remain elusive.Aims This study aimed to identify and validate distinctive acoustic features of healing music.Methods We constructed a healing music dataset(HMD)based on nominations from related professionals and extracted 370 acoustic features.Healing-distinctive acoustic features were identified as those that were(1)independent from genre within the HMD,(2)significantly different from music pieces in a classical music dataset(CMD)and(3)similar to pieces in a five-element music dataset(FEMD).We validated the identified features by comparing jazz pieces in the HMD with a jazz music dataset(JMD).We also examined the emotional properties of the features in a Chinese affective music system(CAMS).Results The HMD comprised 165 pieces.Among all the acoustic features,74.59%shared commonalities across genres,and 26.22%significantly differed between the HMD classical pieces and the CMD.The equivalence test showed that the HMD and FEMD did not differ significantly in 9.46%of the features.The potential healing-distinctive acoustic features were identified as the standard deviation of the roughness,mean and period entropy of the third coefficient of the mel-frequency cepstral coefficients.In a three-dimensional space defined by these features,HMD's jazz pieces could be distinguished from those of the JMD.These three features could significantly predict both subjective valence and arousal ratings in the CAMS.Conclusions The distinctive acoustic features of healing music that have been identified and validated in this study have implications for the development of artificial intelligence models for identifying therapeutic music,particularly in contexts where access to professional expertise may be limited.This study contributes to the growing body of research exploring the potential of digital technologies for healthcare interventions.
文摘Plants are amazing chemical factories,and medicinal plants provide a myriad of pharmaceutically active compounds that have been commonly used as traditional medicines for thousands of years.The practice of traditional medicine in China dates back at least 4,500 years.The Shen Nong Ben Cao Jing("Shen Nong's Herbal Classic"in 770−475 BC)has been considered the oldest list of medicinal plants.Recent rapid economic development has enabled China to invest substantially in science and technology research.In many ethnic groups worldwide,herbal medicines are,in the same way as traditional Chinese medicines,still commonly used today.A wide array of plant-extract health supplements has become increasingly popular in Western societies.Numerous drugs derived from a broad range of plant species have been discoveried,such as taxol and artemisinin and their derivatives.
基金supported by The National Key Research and Development Program(2024YFA0917200)Biosafety Project of Chinese Centre for Disease Control and Prevention(BB2110240090)University of Science and Technology of China Quality Project History of Virology(2023XXSKC03).
文摘Biosafety is essential to ensuring the safe and effective conduct of biological research by minimizing risks associated with laboratory work and biological materials.This paper traces the historical and conceptual development of biosafety,from its origins in pathogen containment to its expansion into broader domains.In the modern context,biosafety also involves the regulation of genetically modified organisms and the strengthening of laboratory oversight mechanisms.Biosafety and biosecurity are closely related in origin.Biosafety focuses on biological risks within laboratory environments,while biosecurity addresses biological risks associated with non-laboratory environments.The article summarizes the development of biosafety,extracting the evolution of its conceptual framework from a historical perspective,condenses and compares its scientific characteristics with those of biosecurity,and applies the methodology of science history to define its conceptual framework.
基金supported by the University of Science and Technology of China Virology History (Grant No. 2024XGHJC26)Wuhan University"VIRUSES"Project (Grant No. BB2110000019)Chinese Academy of Sciences Virology High-Quality Data and Knowledge Resource Center (Grant No. 2019WQZX012)。
文摘Virology,as a branch of microbiology,is a science that studies viruses,covering various aspects of their life activities,such as types,composition,structure,metabolism,growth,reproduction,genetics,evolution,and distribution,as well as their interactions with other organisms and the environment(Flint et al.,2015;Zuo et al.,2024).The scope of virology research is broad,encompassing virus classification,pathogenic mechanisms,genomics,vaccine development,immunology,diagnostics,and virology education and talent training.Significant progress in virology research has greatly promoted advancements in medicine,agriculture,and public health.
文摘目的探讨3.0 T MRI的定量磁敏感成像(QSM)上中央静脉征(CVS)、铁沉积鉴别诊断多发性硬化(MS)与视神经脊髓炎谱系疾病(NMOSD)患者颅内病灶的价值。方法本研究为回顾性研究。收集2018年7月至2020年12月乐山市人民医院和重庆医科大学附属第一医院临床确诊的54例MS患者和49例NMOSD患者。所有患者均接受常规MRI和三维增强T2*加权血管成像(3D-ESWAN),并从3D-ESWAN数据重建滤波相位图和QSM。首先在质子密度(PD)-T2WI筛选MS及NMOSD的颅内病灶,然后在相位图和QSM图上观察病灶位置、CVS以及结节状、环状铁沉积。采用χ^(2)检验比较MS与NMOSD患者颅内病灶位置、CVS、铁沉积的差异。采用受试者操作特征曲线及曲线下面积(AUC)评估CVS、QSM铁沉积鉴别MS和NMOSD的效能。结果 54例MS患者观察到968个颅脑病灶,其中354个病灶有CVS,227个CVS位于侧脑室周围,117个位于深部白质(DWM),10个位于皮层/皮层下;QSM上有372个病灶表现为结节状铁沉积、193个病灶表现为环状铁沉积。48例NMOSD患者中41例观察到247个颅脑病灶,其中4个病灶有CVS,1个位于侧脑室周围,3个位于DWM;QSM上3个病灶有结节状铁沉积。MS与NMOSD患者颅内病灶位于皮层/皮层下、CVS、铁沉积差异有统计学意义(χ^(2)分别为29.33、115.66、258.21,P<0.001)。CVS鉴别MS和NMOSD的AUC为0.941(95%CI 0.887~0.994),灵敏度为96.3%,特异度为91.8%;铁沉积鉴别MS和NMOSD的AUC为0.969(95%CI 0.930~1.000),灵敏度为100%,特异度为93.9%。结论 3.0 T MRI上CVS和铁沉积是MS病灶截然不同于NMOSD病灶的影像学特征,对鉴别二者具有一定的价值。
基金the National Natural Science Foundation of China(32200286)the China Postdoctoral Science Foundation(2022TQ0240,2022M722470)。
文摘Cotton is an irreplaceable economic crop currently domesticated in the human world for its extremely elongated fiber cells specialized in seed epidermis,which makes it of high research and application value.To date,numerous research on cotton has navigated various aspects,from multi-genome assembly,genome editing,mechanism of fiber development,metabolite biosynthesis,and analysis to genetic breeding.Genomic and 3D genomic studies reveal the origin of cotton species and the spatiotemporal asymmetric chromatin structure in fibers.Mature multiple genome editing systems,such as CRISPR/Cas9,Cas12(Cpf1)and cytidine base editing(CBE),have been widely used in the study of candidate genes affecting fiber development.Based on this,the cotton fiber cell development network has been preliminarily drawn.Among them,the MYB-b HLH-WDR(MBW)transcription factor complex and IAA and BR signaling pathway regulate the initiation;various plant hormones,including ethylene,mediated regulatory network and membrane protein overlap fine-regulate elongation.Multistage transcription factors targeting Ces A 4,7,and 8 specifically dominate the whole process of secondary cell wall thickening.And fluorescently labeled cytoskeletal proteins can observe real-time dynamic changes in fiber development.Furthermore,research on the synthesis of cotton secondary metabolite gossypol,resistance to diseases and insect pests,plant architecture regulation,and seed oil utilization are all conducive to finding more high-quality breeding-related genes and subsequently facilitating the cultivation of better cotton varieties.This review summarizes the paramount research achievements in cotton molecular biology over the last few decades from the above aspects,thereby enabling us to conduct a status review on the current studies of cotton and provide strong theoretical support for the future direction.
基金This work was supported by National Natural Science Foundation of China （31200615, 31600238）, Postgraduate Research and Innovation Project of Hunan Province （CX2014B302）, National Key Laboratory Cultivation Base Construction Project （15KFXM09）, the National Science-Technology Support Plan Projects of China （2012BAI29B04）, The talent introduction Science Foundation of Hunan Agricultural University （13YJ09）, and the Natural Science Foundation of Hunan Province （2016JJ4040）.
文摘The overuse of antibiotics in animal agriculture and medicine has caused a series of potential threats to public health. Macleaya cordata is a medicinal plant species from the Papaveraceae family, providing a safe resource for the manufacture of antimicrobial feed additive for livestock. The active constituents from M. cordata are known to include benzylisoquinoline alkaloids （BIAs） such as sanguinarine （SAN） and chelerythrine （CHE）, but their metabolic pathways have yet to be studied in this non-model plant. The active biosynthesis of SAN and CHE in M. cordata was first examined and confirmed by feeding ^13C-labeled tyrosine. To gain further insights, we de novo sequenced the whole genome of M. cordata, the first to be sequenced from the Papaveraceae family. The M. cordata genome covering 378 Mb encodes 22,328 predicted protein-coding genes with 43.5% being transposable elements. As a member of basal eudicot, M. cordata genome lacks the paleohexaploidy event that occurred in almost all eudicots. From the genomics data, a complete set of 16 metabolic genes for SAN and CHE biosynthesis was retrieved, and 14 of their biochemical activities were validated. These genomics and metabolic data show the conserved BIA metabolic pathways in M. cordata and provide the knowledge foundation for future productions of SAN and CHE by crop improvement or microbial pathway reconstruction.
基金the State Key Basic Research Program of China (2013CB127000)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB11030300)+1 种基金the National Natural Science Foundation of China (31300255)the Special Fund for Shanghai Landscaping Administration Bureau Program (G142425, F112418).
文摘Sesquiterpenoids are a class of 15-carbon secondary metabolites that play diverse roles in plant adaptation to environment. Cotton plants accumulate a large amount of sesquiterpene aldehydes （including gossypol） as phytoalexins against pathogens and herbivores. They are stored in pigment glands of aerial organs and in epidermal layers of roots. Several enzymes of goss- ypol biosynthesis pathway have been characterized, including 3-hydroxy-3-methylglutaryl coenzyme A reductase （HMGR） and farnesyl diphosphate synthase （FPS） that catalyze the formation of the precursor farnesyl diphosphate （FPP）, （＋）-6-cadinene synthase （CDN） which is the first enzyme committed to gossypol biosynthesis, and the downstream enzymes of CYP706B 1 and methyltransferase. Expressions of these genes are tightly regulated during cotton plants development and in- duced by jasmonate and fungi elicitors. The transcription factor GaWRKY1 has been shown to be involved in gossypol path- way regulation. Recent development of new genomic platforms and methods and releases of diploid and tetraploid cotton ge- nome sequences will greatly facilitate the elucidation of gossypol biosynthetic pathway and its regulation.
