This study aims to assess the comprehensive strengthening effect of a steel-ultra high performance concrete(UHPC)composite strengthening method.The axial force-moment interaction curve(N-M curve)was calculated in a no...This study aims to assess the comprehensive strengthening effect of a steel-ultra high performance concrete(UHPC)composite strengthening method.The axial force-moment interaction curve(N-M curve)was calculated in a novel way,using cross-sectional strains at ultimate states as well as real-time stress measurements for each material.The enclosed area of the N-M curve was defined as a comprehensive performance index for the system.We validate our approach with comparisons to numerical modeling and full-scale four-point bending experiments.Additionally,strengthening effects were compared for different sagging and hogging moments based on material stress responses,and the impact of various strengthening parameters was analyzed.We find that the N-M curve of the strengthened cross-section envelops that of the un-strengthened cross-section.Notably,improvements in flexural capacity are greater under sagging moments during the large eccentric failure stage,and greater under hogging moments during the small eccentric failure stage.This discrepancy is attributed to the strength utilization of strengthening materials.These findings provide a reference for understanding the strengthening effects and parameters of steel-UHPC composite.展开更多
Purpose–For the commonly used concrete mix for railway tunnel linings,concrete model specimens were made,and springback and core drilling tests were conducted at different ages.The springback strength was measured to...Purpose–For the commonly used concrete mix for railway tunnel linings,concrete model specimens were made,and springback and core drilling tests were conducted at different ages.The springback strength was measured to the compressive strength of the core sample with a diameter of 100mm and a height-to-diameter ratio of 1:1.By comparing the measured strength values,the relationship between the measured values under different strength measurement methods was analyzed.Design/methodology/approach–A comparative test of the core drilling method and the rebound method was conducted on the side walls of tunnel linings in some under-construction railways to study the feasibility of the rebound method in engineering quality supervision and inspection.Findings–Tests showed that the rebound strength was positively correlated with the core drill strength.The core drill test strength was significantly higher than the rebound test strength,and the strength still increased after 56 days of age.The rebound method is suitable for the general survey of concrete strength during the construction process and is not suitable for direct supervision and inspection.Originality/value–By studying the correlation of test strength of tunnel lining concrete using two methods,the differences in test results of different methods are proposed to provide a reference for the test and evaluation of tunnel lining strength in railway engineering.展开更多
Currently,chemical furnaces play an important role in the chemical industry.It is necessary to ensure their quality and operation performance,so as to guarantee the efficiency of chemical production.Compared with othe...Currently,chemical furnaces play an important role in the chemical industry.It is necessary to ensure their quality and operation performance,so as to guarantee the efficiency of chemical production.Compared with other furnaces,chemical furnaces have strong particularity,which puts forward higher requirements for the thermal shock resistance of the refractories of furnace linings.This paper studied the thermal shock resistance of the refractories for chemical furnace linings,and proposed measures for improvement,providing experience and technical support for the safe production of chemical enterprises.展开更多
When only a portion of the shield lining structures in a full-line tunnel are overloaded,their bearing and failure characteristics are significantly different from those in the full-line overloaded case.In existing st...When only a portion of the shield lining structures in a full-line tunnel are overloaded,their bearing and failure characteristics are significantly different from those in the full-line overloaded case.In existing studies,one or several segmental lining rings have been studied,with overload applied to selected lining rings to analyze the performance evolution of the lining structures;however,this approach fails to reveal the bearing and failure characteristics of shield lining rings under localized overload.To address this research gap,we employ 3D finite element modeling to investigate the mechanical performance and failure mechanisms of shield segmental linings under localized overload conditions,and compare the results with full-line overload scenarios.Additionally,the impact of reinforcing shield segmental linings with steel rings is studied to address issues arising from localized overloads.The results indicate that localized overloads lead to significant ring joint dislocation and higher stress on longitudinal bolts,potentially causing longitudinal bolt failure.Furthermore,the overall deformation of lining rings,segmental joint opening,and stress in circumferential bolts and steel bars is lower compared to full-line overloads.For the same overload level,the convergence deformation of the lining under full-line overload is 1.5 to 2.0 times higher than that under localized overload.For localized overload situations,a reinforcement scheme with steel rings spanning across two adjacent lining rings is more effective than installing steel rings within individual lining rings.This spanning ring reinforcement strategy not only enhances the structural rigidity of each ring,but also limits joint dislocation and reduces stress on longitudinal bolts,with the reduction in maximum ring joint dislocation ranging from 70%to 82%and the reduction in maximum longitudinal bolt stress ranging from 19%to 57%compared to reinforcement within rings.展开更多
Detecting internal defects,particularly voids behind linings,is critical for ensuring the structural integrity of aging high-speed rail(HSR)tunnel networks.While ground-penetrating radar(GPR)is widely employed,systema...Detecting internal defects,particularly voids behind linings,is critical for ensuring the structural integrity of aging high-speed rail(HSR)tunnel networks.While ground-penetrating radar(GPR)is widely employed,systematic quantification of performance boundaries for air-coupled(A-CGPR)and ground-coupled(G-CGPR)systems within the complex electromagnetic environment of multilayer reinforced HSR tunnels remains limited.This study establishes physics-based quantitative performance limits for A-CGPR and G-CGPR through rigorously validated GPRMax finite-difference time-domain(FDTD)simulations and comprehensive field validation over a 300 m operational HSR tunnel section.Key performance metrics were quantified as functions of:(a)detection distance(A-CGPR:2.0–4.5 m;G-CGPR:≤0.1 m),(b)antenna frequency(A-CGPR:300 MHz;G-CGPR:400/900 MHz),(c)reinforcement configuration(unreinforced,single-layer,multilayer rebar),and(d)void geometry(axial length:0.1–1.0 m;radial depth:0.1–0.5 m).Key findings demonstrate:a.A-CGPR(300 MHz):Reliably detects axial voids≥0.3 m at distances≤3 m in minimally reinforced(single-layer rebar)linings(field R2=0.89).Performance degrades significantly at distances>3 m(>60%signal attenuation at 4.5 m)or under multilayer rebar interference,causing 25%–40%accuracy loss for voids<0.3 m.Optimal distance:2.0–2.5 m.b.G-CGPR(900 MHz):Achieves<5%size measurement error for axial voids≥0.1 m and radial voids≥0.2 m in unreinforced linings.Resolution degrades under multilayer reinforcement due to severe signal attenuation,increasing axial void detection error to 10%–20%for voids≥0.3 m and constraining radial size measurement.c.Synergistic Framework:A hybrid inspection protocol is proposed,integrating A-CGPR(20 km/h)for rapid large-area screening and targeted G-CGPR(3 km/h)for high-resolution verification of identified anomalies.This framework enhances NDT efficiency while reducing estimated lifecycle inspection costs by 34%compared to G-CGPR alone.This research provides the first physics-derived quantitative detection thresholds for A-CGPR and G-CGPR in multi-rebar HSR tunnels,validated through field-correlated simulations.Future work will focus on multi-frequency antenna arrays and deep learning algorithms to mitigate reinforcement interference.The established performance boundaries and hybrid framework offer critical guidance for optimizing tunnel lining inspection strategies in extensive HSR networks.展开更多
Cement channel linings in an urban stream in St. Louis, Missouri increase event water contributions during flooding, shorten transport times, and magnify geochemical variability on both short and seasonal timescales d...Cement channel linings in an urban stream in St. Louis, Missouri increase event water contributions during flooding, shorten transport times, and magnify geochemical variability on both short and seasonal timescales due to disruption of hyporheic flowpaths. Detailed analyses of water isotopes, major and trace elements, and in situ water quality data for an individual flood event reveal that baseflow contributions rise by 8% only 320 m downstream of the point where this particular channel changes from cement-lined to unlined. However, additional hydrograph separations indicate baseflow contributions are variable and can be much higher（average baseflow increase is 16%）. Stream electrical conductivity（EC） and solute concentrations in the lined reach were up to 25% lower during peak flow than in the unlined channel, indicating a greater event flow fraction. In contrast, during low flow, stream EC and solute concentrations in the lined reach were up to 30% higher due to the restricted inflow of more dilute groundwater. Over longer timescales, EC, solute concentrations, turbidity, and bacterial loads decrease downstream signifying increasing contributions of dilute baseflow. The decreased connectivity of surface waters and groundwaters along the hyporheic zone in lined channels increases the hydrologic and geochemical variability of urban streams.展开更多
For long-distance water conveyance shield tunnels in operation,the high internal water pressure may cause excessive deformation of composite linings,affecting their structural integrity and serviceability.However,the ...For long-distance water conveyance shield tunnels in operation,the high internal water pressure may cause excessive deformation of composite linings,affecting their structural integrity and serviceability.However,the deformation and failure characteristics of lining structures under internal water pressure are not well investigated in the literature,particularly for three-layer composite linings.This study presents an in situ experimental investigation on the response of two types of composite linings(i.e.separated and combined lining structures)subjected to internal pressures,in which a fiber optic nerve system(FONS)equipped with distributed strain and displacement sensing nerves was employed to monitor the performance of the two composite linings during testing.The experimental results clearly show that the damage of the tunnel lining under different internal pressures was mainly located in the self-compaction concrete layer.The separated lining structure responded more aggressively to the variations in internal pressures than the combined one.Moreover,two evaluation indices,i.e.radial displacement and effective stiffness coefficient,are proposed for describing the changes in the structural bearing performance.The effective stiffness coefficients of the two types of lining structures were reduced by 39.4%and 29.5%,respectively.Considering the convenience of field monitoring,it is suggested that the average strains at different layers can be used as characteristic parameters for estimating the health conditions of lining structures in service.The analysis results provide a practical reference for the design and health evaluation of water conveyance shield tunnels with composite linings.展开更多
During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield projects.Differential ...During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield projects.Differential floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the tunnel.In this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel excavation.The mechanism and factors causing upward movement of the tunnel lining are comprehensively summarized.Twelve input variables were selected according to results from analysis of influencing factors.The prediction performance of two models,PSO-RF and RF(default)were compared.The Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of linings.The PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings.展开更多
This paper represented the numerical analysis of the FRP （fiber reinforced plastics） tunnel lining which was used for maintaining the old tunnel. An old tunnel covered with a concrete is prone to deteriorate due to ...This paper represented the numerical analysis of the FRP （fiber reinforced plastics） tunnel lining which was used for maintaining the old tunnel. An old tunnel covered with a concrete is prone to deteriorate due to an aging effect and a v^ater penetration. In the rehabilitation of lining concrete, a steel plate and FRP or carbon sheet have been applied. However, these sheets show small flexural rigidity and do not flow out the penetrating water. In this paper, FRP corrugate sheet was proposed. The tunnel lining was made by FRP corrugate sheet that supported the lining concrete in the tunnel and flowed the water and the moisture swept on the tunnel surface. The FRP corrugate sheet was supported by the anchor bolts. In numerical analyses, the finite element degenerate shell was adopted to represent the FRP sheet behavior. Assuming that the concrete liner at the top was fallen down, the peeled concrete was applied as the load. From the numerical analysis, the effectiveness of the FRO corrugate sheet was confirmed.展开更多
The nanoporous thermal insulating material was prepared by using fumed silica,SiC powder and glass fiber as starting materials,the appropriate thickness of the nanoporous thermal insulating material lined in ladle was...The nanoporous thermal insulating material was prepared by using fumed silica,SiC powder and glass fiber as starting materials,the appropriate thickness of the nanoporous thermal insulating material lined in ladle was discussed by the simulation method,and the effect of its application as ladle lining was investigated.The results show that the thermal conductivity of the nanoporous thermal insulating material prepared in composition of fumed silica： SiC powder： glass fiber =75： 20：5 （in mass） is 0.023 W · m^-1 · K^-1 at 1 000 ℃,the appropriate thickness of the nanoporous thermal insulating material lined in ladle is ≤ 5 mm and the average temperature of the ladle outside surface when lined with the nanoporous thermal insulating material is 95 ℃ lower than that with the ordinary thermal insulating material.展开更多
“Are you dead?”It's not a morbid joke-it's the literal translation of the name of Chinese app Sileme,which went viral around the country in early January.However,amid public controversy over its unsettling c...“Are you dead?”It's not a morbid joke-it's the literal translation of the name of Chinese app Sileme,which went viral around the country in early January.However,amid public controversy over its unsettling connotations,the development team rebranded the app as Demumu on January 14,be-fore it was removed from the app stores of Apple and Android on January 15.展开更多
Multi-layer linings have been widely used in deep rheological soft rock tunnels for the excellent performance in preventing large-deformation hazards.Previous studies have focused on the bearing capability of multi-la...Multi-layer linings have been widely used in deep rheological soft rock tunnels for the excellent performance in preventing large-deformation hazards.Previous studies have focused on the bearing capability of multi-layer lining,however,its failure characteristics and synergistic load-bearing mechanisms under high geo-stress are still unclear.To fill the gap,three-dimensional geomechanical model tests were conducted and synergistic mechanisms were analysed in this study.The model test was divided into normal loading,excavat-ing,and overloading stages.The surrounding rock deformation was monitored by using an improved high-precise extensometer mea-surement system.Results show that the largest radial deformation appears on the sidewall,followed by the floor and vault during the excavating stage.The relative convergence deformation of sidewalls springing reaches 1.32 mm.The failure characteristics of the multi-layer linings during the overloading stage undergo an evolution of stability,crack initiation,local failure,and collapse,with a safety factor of 1.0-1.6,1.6-2.0,and 2.0-2.2,respectively.The synergistic load-bearing mechanism analysis results suggest that the early stiffness and late yielding deformation capacity of large deformation support measures play important roles in stability maintenance both in the construction and operation of deep soft rock tunnels.Therefore,the combination of yielding support or a compressible layer with reinforced support is recommended to mitigate the effect of the high geo-stress.展开更多
The construction of new tunnels induces additional/unloading pressures on existing tunnels,subsequently affecting structural integrity.To assess tunnel response,a full-scale multiring test was conducted,simulating wat...The construction of new tunnels induces additional/unloading pressures on existing tunnels,subsequently affecting structural integrity.To assess tunnel response,a full-scale multiring test was conducted,simulating water/soil and additional/unloading pressure from a new undercrossing tunnel.Key parameters analyzed included additional/unloading pressure,tunnel axis distance,longitudinal forces,and loading levels to evaluate structural deformations and joint behavior.Results showed that additional/unloading forces significantly impact structural ring convergence during tunnel crossing stage.These forces vary nonlinearly with distance from the crossing point,but their influence is linear.Further,joint opening and dislocation not only depend on external load but also on the staggering effect and segment geometry.Reducing the tunnel axis distance meaningfully upsurges unloading forces,leading to higher strains at joints and the segment body.Longitudinal force,directly proportional to the staggering effect,reduces structural deformations;for instance,even a 1%force mitigates up to 32.05%joint dislocation.Lifecycle analysis revealed the tunnel crossing stage is far more vulnerable than the construction/operation stage,and tunnel axis distances of twice or more of the diameter can be considered safe.This study provides practical insights for engineers to mitigate risks during tunnel crossings and enhances safety guidelines for life cycle management.展开更多
Steel fiber reinforced concrete-reinforced concrete(SFRC-RC)composite linings are popular in shield tunnel construction due to exceptional strength and waterproofing properties.Non-destructive testing methods are esse...Steel fiber reinforced concrete-reinforced concrete(SFRC-RC)composite linings are popular in shield tunnel construction due to exceptional strength and waterproofing properties.Non-destructive testing methods are essential for assessing the quality of these linings and ensuring tunnel construction safety.This study investigates the potential and parameters of ground penetrating radar(GPR)detection for the composite linings,using the Deep Tunnel Sewerage System-Phase 2 project in Singapore as a case study.The gprMax simulations incorporated the random distribution and precise parameters of steel fibers to conduct preliminary frequency selection studies.The structural setup of the model experiments mirrored that of the actual tunnel,allowing for an analysis of GPR penetration capabilities at various frequencies.Field testing provided authentic GPR data,validating conclusions drawn from simulations and model experiments and examining GPR power attenuation patterns.Findings indicate that GPR is effective for the quality detection of composite linings.The optimal frequency for detecting SFRC-RC composite linings is 300 MHz,which resolves the interfaces of different layered media.Based on single-parameter exponential and power function fitting,empirical formulas for power attenuation quantitatively characterize GPR signal attenuation in SFRC-RC composite linings.This paper offers valuable references for GPR detection of SFRC-RC composite linings.展开更多
Metro(subway)is an advanced public transport infrastructure system in urban areas with high capacity.The traffic operation of a metro is not affected by other vehicle traffic thanks to underground tunnels.With these b...Metro(subway)is an advanced public transport infrastructure system in urban areas with high capacity.The traffic operation of a metro is not affected by other vehicle traffic thanks to underground tunnels.With these benefits metro lines are preferred to solve the traffic problem in urbanized cities such as Istanbul,which is the focus of this study.Metro projects require huge amounts of budgets to be built.Putting these projects into service in targeted time is of great importance.The objective of this study is to minimize total metro construction project time by utilizing fiber reinforcement in tunnel linings.In this research,using fiber reinforcement to construct primary(initial)tunnel linings and secondary(final)tunnel linings of the metro projects are analyzed in terms of project duration.After comparison of two railway tunnel projects,evaluations and observations of a completed metro project revealed that using fiber reinforcement for either the primary lining or the final lining of tunnels reduces construction time of metro station tunnels by 25%.In addition,using fiber reinforcement to construct both the final lining and the primary lining of tunnels reduces construction time of the metro station tunnels and the whole metro project by 47% and 22%,respectively.The results of this study can be useful for completing challenging metro projects and putting it into service within the targeted time.展开更多
The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isome...The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isomers,such as boiling point,of formation are found to be better measured by the ABS index than by the Randi,atom-bond connectivity(ABC),and sum-connectivity(SC)indices.One important source of information for researching the molecular structure is the bounds for its topological indices.The extrema of the ABS index of the line,total,and Mycielski graphs are calculated in this work.Moreover,the pertinent extremal graphs were illustrated.展开更多
Glaucoma is characterized by chronic progressive optic nerve damage and retinal ganglion cell death.Although extensive research has been conducted on neuroprotection for retinal ganglion cells,there is still no treatm...Glaucoma is characterized by chronic progressive optic nerve damage and retinal ganglion cell death.Although extensive research has been conducted on neuroprotection for retinal ganglion cells,there is still no treatment for clinical use.Recent evidence shows that extracellular vesicles isolated from a variety of stem cells are efficacious in retinal ganglion cell neuroprotection.In this study,we tested the novel extracellular vesicle source of the retinal progenitor R-28 cell line in vitro and in vivo.We isolated and characterized extracellular vesicles from R-28 cells and tested their therapeutic efficacy in terms of retinal ganglion cell survival in vitro and in an in vivo glaucoma model,measuring retinal ganglion cell survival and preservation of their axons.Additionally,we tested extracellular vesicles for their neuroprotective capacity in retinal ganglion cells differentiated from human embryonic stem cells.Finally,we investigated miRNA changes in retinal ganglion cells with R-28 extracellular vesicle treatment,and predicted possible pathways that may be modulated.R-28 extracellular vesicles improved retinal ganglion cell survival but failed to preserve axons significantly.Moreover,the results also illustrated the neuroprotection of R-28 extracellular vesicles on human retinal ganglion cells.Finally,we also showed changes in hsa-miRNA-4443,hsa-miRNA-216a-5p,hsa-let-7e-5p,hsa-miRNA-374b-5p,hsa-miRNA-331-3p,and hsa-miRNA-421 expressions,which may have neuroprotective potential on retinal ganglion cell degeneration.This study will pave the way for miRNA and extracellular vesicle-based neuroprotective therapies for glaucoma.展开更多
Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in oper...Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in operator workloads and significantly increase the complexity of scheduling.To address this challenge,this study investigates the Aircraft Pulsating Assembly Line Scheduling Problem(APALSP)under skilled operator allocation,with the objective of minimizing assembly completion time.A mathematical model considering skilled operator allocation is developed,and a Q-Learning improved Particle Swarm Optimization algorithm(QLPSO)is proposed.In the algorithm design,a reverse scheduling strategy is adopted to effectively manage large-scale precedence constraints.Moreover,a reverse sequence encoding method is introduced to generate operation sequences,while a time decoding mechanism is employed to determine completion times.The problem is further reformulated as a Markov Decision Process(MDP)with explicitly defined state and action spaces.Within QLPSO,the Q-learning mechanism adaptively adjusts inertia weights and learning factors,thereby achieving a balance between exploration capability and convergence performance.To validate the effectiveness of the proposed approach,extensive computational experiments are conducted on benchmark instances of different scales,including small,medium,large,and ultra-large cases.The results demonstrate that QLPSO consistently delivers stable and high-quality solutions across all scenarios.In ultra-large-scale instances,it improves the best solution by 25.2%compared with the Genetic Algorithm(GA)and enhances the average solution by 16.9%over the Q-learning algorithm,showing clear advantages over the comparative methods.These findings not only confirm the effectiveness of the proposed algorithm but also provide valuable theoretical references and practical guidance for the intelligent scheduling optimization of aircraft pulsating assembly lines.展开更多
Poly-and perfluoroalkyl substances(PFAS),including perfluorooctanoic acid(PFOA)and perfluorooctane sul-fonate(PFOS),are persistent environmental pollutants with potential toxicological effects on human health.The aim ...Poly-and perfluoroalkyl substances(PFAS),including perfluorooctanoic acid(PFOA)and perfluorooctane sul-fonate(PFOS),are persistent environmental pollutants with potential toxicological effects on human health.The aim of this study was to investigate the impact of PFOS and PFOA on the effectiveness of selected drugs used in the treatment of prostate cancer based on in vitro tests on cell lines.Three cell lines were used in the study:two human prostate cancer cells(DU-145 and PC3)and one human normal prostate cell line(PNT1A).Using dose-response experiments,it was observed that PFAS had differential effects on cancer and normal cells.At low concentrations,PFOA and PFOS stimulated the proliferation of cancer cells,particularly PC3,while higher concentrations led to reduced viability.In normal cells,PFOS exhibited greater cytotoxicity compared to PFOA.Furthermore,PFOS enhanced docetaxel cytotoxicity in PC3 cells but reduced its efficacy in DU-145 cells.Similarly,PFOA diminished cabazitaxel effectiveness in DU-145 cells,suggesting PFAS-drug interactions may depend on the cell type,drug,and PFAS concentration.Results suggest that PFAS may influence cellular processes through receptor-mediated pathways,oxidative stress modulation,and protein binding,altering drug bioavailability and cellular uptake.The study also highlights the non-monotonic dose-response relationships observed in PFAS-treated cells.These findings raise concerns about the potential risks associated with PFAS exposure,particularly in the context of cancer treatment.Future studies should focus on long-term,low-dose PFAS exposure,the use of primary cells,and the molecular mechanisms driving these interactions to better inform therapeutic strategies.展开更多
Thinopyrum ponticum(2n=10×=70),a wild relative of common wheat(Triticum aestivum L.),is considered an invaluable genetic resource for wheat improvement due to its abundance of genes conferring resistance to bioti...Thinopyrum ponticum(2n=10×=70),a wild relative of common wheat(Triticum aestivum L.),is considered an invaluable genetic resource for wheat improvement due to its abundance of genes conferring resistance to biotic and abiotic stresses.This study focused on the CH97 line,derived from the BC1F7 progeny of a cross between wheat cv.7182 and Th.ponticum.Cytological evidence showed that CH97 has 42 chromosomes,forming 21 bivalents at meiotic metaphase I,with the bivalents subsequently separating and moving to opposite poles during meiotic anaphase I.Through a combination of fluorescence in situ hybridization(FISH),genomic in situ hybridization(GISH),multicolor GISH(mc-GISH),and liquid array analysis,it was determined that CH97 comprises 40 wheat chromosomes and two alien chromosomes from the Ee genome of Th.ponticum,featuring the absence of a pair of 5D chromosomes and variations in 1B,6B,and 7B chromosomes.These findings confirm that CH97 is a stable wheat-Th.ponticum 5E(5D)alien disomic substitution line.Inoculation experiments revealed that CH97 exhibits high resistance to wheat powdery mildew and stripe rust throughout the growth period,in contrast to the highly susceptible common wheat parent 7182.Compared to 7182,CH97 displayed improvements in thousand-kernel weight and kernel length.Additionally,utilizing specific-locus amplified fragment sequencing(SLAF-seq)technology,chromosome 5E-specific molecular markers were developed and validated,achieving a 33.3% success rate,facilitating marker-assisted selection for disease resistance in wheat.Overall,the CH97 substitution line,with its resistance to diseases and improved agronomic traits,represents valuable new germplasm for wheat chromosome engineering and breeding.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51938005,52090082,and 52378395)the National Key Research and Development Program of China(No.2023YFB2604402).
文摘This study aims to assess the comprehensive strengthening effect of a steel-ultra high performance concrete(UHPC)composite strengthening method.The axial force-moment interaction curve(N-M curve)was calculated in a novel way,using cross-sectional strains at ultimate states as well as real-time stress measurements for each material.The enclosed area of the N-M curve was defined as a comprehensive performance index for the system.We validate our approach with comparisons to numerical modeling and full-scale four-point bending experiments.Additionally,strengthening effects were compared for different sagging and hogging moments based on material stress responses,and the impact of various strengthening parameters was analyzed.We find that the N-M curve of the strengthened cross-section envelops that of the un-strengthened cross-section.Notably,improvements in flexural capacity are greater under sagging moments during the large eccentric failure stage,and greater under hogging moments during the small eccentric failure stage.This discrepancy is attributed to the strength utilization of strengthening materials.These findings provide a reference for understanding the strengthening effects and parameters of steel-UHPC composite.
文摘Purpose–For the commonly used concrete mix for railway tunnel linings,concrete model specimens were made,and springback and core drilling tests were conducted at different ages.The springback strength was measured to the compressive strength of the core sample with a diameter of 100mm and a height-to-diameter ratio of 1:1.By comparing the measured strength values,the relationship between the measured values under different strength measurement methods was analyzed.Design/methodology/approach–A comparative test of the core drilling method and the rebound method was conducted on the side walls of tunnel linings in some under-construction railways to study the feasibility of the rebound method in engineering quality supervision and inspection.Findings–Tests showed that the rebound strength was positively correlated with the core drill strength.The core drill test strength was significantly higher than the rebound test strength,and the strength still increased after 56 days of age.The rebound method is suitable for the general survey of concrete strength during the construction process and is not suitable for direct supervision and inspection.Originality/value–By studying the correlation of test strength of tunnel lining concrete using two methods,the differences in test results of different methods are proposed to provide a reference for the test and evaluation of tunnel lining strength in railway engineering.
文摘Currently,chemical furnaces play an important role in the chemical industry.It is necessary to ensure their quality and operation performance,so as to guarantee the efficiency of chemical production.Compared with other furnaces,chemical furnaces have strong particularity,which puts forward higher requirements for the thermal shock resistance of the refractories of furnace linings.This paper studied the thermal shock resistance of the refractories for chemical furnace linings,and proposed measures for improvement,providing experience and technical support for the safe production of chemical enterprises.
基金supported by the National Natural Science Foundation of China(No.52008308).
文摘When only a portion of the shield lining structures in a full-line tunnel are overloaded,their bearing and failure characteristics are significantly different from those in the full-line overloaded case.In existing studies,one or several segmental lining rings have been studied,with overload applied to selected lining rings to analyze the performance evolution of the lining structures;however,this approach fails to reveal the bearing and failure characteristics of shield lining rings under localized overload.To address this research gap,we employ 3D finite element modeling to investigate the mechanical performance and failure mechanisms of shield segmental linings under localized overload conditions,and compare the results with full-line overload scenarios.Additionally,the impact of reinforcing shield segmental linings with steel rings is studied to address issues arising from localized overloads.The results indicate that localized overloads lead to significant ring joint dislocation and higher stress on longitudinal bolts,potentially causing longitudinal bolt failure.Furthermore,the overall deformation of lining rings,segmental joint opening,and stress in circumferential bolts and steel bars is lower compared to full-line overloads.For the same overload level,the convergence deformation of the lining under full-line overload is 1.5 to 2.0 times higher than that under localized overload.For localized overload situations,a reinforcement scheme with steel rings spanning across two adjacent lining rings is more effective than installing steel rings within individual lining rings.This spanning ring reinforcement strategy not only enhances the structural rigidity of each ring,but also limits joint dislocation and reduces stress on longitudinal bolts,with the reduction in maximum ring joint dislocation ranging from 70%to 82%and the reduction in maximum longitudinal bolt stress ranging from 19%to 57%compared to reinforcement within rings.
基金funded by the Key Project of Science&Technology Research ofChina Academy of Railway Sciences,grant number 2023YJ022.
文摘Detecting internal defects,particularly voids behind linings,is critical for ensuring the structural integrity of aging high-speed rail(HSR)tunnel networks.While ground-penetrating radar(GPR)is widely employed,systematic quantification of performance boundaries for air-coupled(A-CGPR)and ground-coupled(G-CGPR)systems within the complex electromagnetic environment of multilayer reinforced HSR tunnels remains limited.This study establishes physics-based quantitative performance limits for A-CGPR and G-CGPR through rigorously validated GPRMax finite-difference time-domain(FDTD)simulations and comprehensive field validation over a 300 m operational HSR tunnel section.Key performance metrics were quantified as functions of:(a)detection distance(A-CGPR:2.0–4.5 m;G-CGPR:≤0.1 m),(b)antenna frequency(A-CGPR:300 MHz;G-CGPR:400/900 MHz),(c)reinforcement configuration(unreinforced,single-layer,multilayer rebar),and(d)void geometry(axial length:0.1–1.0 m;radial depth:0.1–0.5 m).Key findings demonstrate:a.A-CGPR(300 MHz):Reliably detects axial voids≥0.3 m at distances≤3 m in minimally reinforced(single-layer rebar)linings(field R2=0.89).Performance degrades significantly at distances>3 m(>60%signal attenuation at 4.5 m)or under multilayer rebar interference,causing 25%–40%accuracy loss for voids<0.3 m.Optimal distance:2.0–2.5 m.b.G-CGPR(900 MHz):Achieves<5%size measurement error for axial voids≥0.1 m and radial voids≥0.2 m in unreinforced linings.Resolution degrades under multilayer reinforcement due to severe signal attenuation,increasing axial void detection error to 10%–20%for voids≥0.3 m and constraining radial size measurement.c.Synergistic Framework:A hybrid inspection protocol is proposed,integrating A-CGPR(20 km/h)for rapid large-area screening and targeted G-CGPR(3 km/h)for high-resolution verification of identified anomalies.This framework enhances NDT efficiency while reducing estimated lifecycle inspection costs by 34%compared to G-CGPR alone.This research provides the first physics-derived quantitative detection thresholds for A-CGPR and G-CGPR in multi-rebar HSR tunnels,validated through field-correlated simulations.Future work will focus on multi-frequency antenna arrays and deep learning algorithms to mitigate reinforcement interference.The established performance boundaries and hybrid framework offer critical guidance for optimizing tunnel lining inspection strategies in extensive HSR networks.
基金partially supported by a USEPA subcontract from the Watershed Management Plan Development Grant Program through the Missouri Department of Natural Resources to the University City Department of Public Works (No. G06-NPS-18)ICP-OES and ICP-MS analyses were performed at the Nano Research Facility (NRF) of Washington University+1 种基金a member of the National Nanotechnology Infrastructure Network (NNIN), which is supported by the National Science Foundation (No. ECS-0335765)two anonymous reviewers for constructive comments that helped improve this manuscript
文摘Cement channel linings in an urban stream in St. Louis, Missouri increase event water contributions during flooding, shorten transport times, and magnify geochemical variability on both short and seasonal timescales due to disruption of hyporheic flowpaths. Detailed analyses of water isotopes, major and trace elements, and in situ water quality data for an individual flood event reveal that baseflow contributions rise by 8% only 320 m downstream of the point where this particular channel changes from cement-lined to unlined. However, additional hydrograph separations indicate baseflow contributions are variable and can be much higher（average baseflow increase is 16%）. Stream electrical conductivity（EC） and solute concentrations in the lined reach were up to 25% lower during peak flow than in the unlined channel, indicating a greater event flow fraction. In contrast, during low flow, stream EC and solute concentrations in the lined reach were up to 30% higher due to the restricted inflow of more dilute groundwater. Over longer timescales, EC, solute concentrations, turbidity, and bacterial loads decrease downstream signifying increasing contributions of dilute baseflow. The decreased connectivity of surface waters and groundwaters along the hyporheic zone in lined channels increases the hydrologic and geochemical variability of urban streams.
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.42225702 and 42077235)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(Grant No.KYCX22_0162)the scientific research project of Guangdong Yue Hai Pearl River Delta Water Supply Co.,Ltd.The authors thank Guangqing Wei,Lixiang Jia,and Zhen Zhang,all of Suzhou Nanzee Sensing Co.,Ltd.,for their assistance in the tests.The valuable suggestions provided by Professor Baojun Wang,Nanjing University,are also gratefully acknowledged.
文摘For long-distance water conveyance shield tunnels in operation,the high internal water pressure may cause excessive deformation of composite linings,affecting their structural integrity and serviceability.However,the deformation and failure characteristics of lining structures under internal water pressure are not well investigated in the literature,particularly for three-layer composite linings.This study presents an in situ experimental investigation on the response of two types of composite linings(i.e.separated and combined lining structures)subjected to internal pressures,in which a fiber optic nerve system(FONS)equipped with distributed strain and displacement sensing nerves was employed to monitor the performance of the two composite linings during testing.The experimental results clearly show that the damage of the tunnel lining under different internal pressures was mainly located in the self-compaction concrete layer.The separated lining structure responded more aggressively to the variations in internal pressures than the combined one.Moreover,two evaluation indices,i.e.radial displacement and effective stiffness coefficient,are proposed for describing the changes in the structural bearing performance.The effective stiffness coefficients of the two types of lining structures were reduced by 39.4%and 29.5%,respectively.Considering the convenience of field monitoring,it is suggested that the average strains at different layers can be used as characteristic parameters for estimating the health conditions of lining structures in service.The analysis results provide a practical reference for the design and health evaluation of water conveyance shield tunnels with composite linings.
基金supported by the Basic Science Center Program for Multiphase Evolution in Hyper Gravity of the National Natural Science Foundation of China(No.51988101)the National Natural Science Foundation of China(No.52178306)the Zhejiang Provincial Natural Science Foundation of China(No.LR19E080002).
文摘During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield projects.Differential floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the tunnel.In this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel excavation.The mechanism and factors causing upward movement of the tunnel lining are comprehensively summarized.Twelve input variables were selected according to results from analysis of influencing factors.The prediction performance of two models,PSO-RF and RF(default)were compared.The Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of linings.The PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings.
文摘This paper represented the numerical analysis of the FRP （fiber reinforced plastics） tunnel lining which was used for maintaining the old tunnel. An old tunnel covered with a concrete is prone to deteriorate due to an aging effect and a v^ater penetration. In the rehabilitation of lining concrete, a steel plate and FRP or carbon sheet have been applied. However, these sheets show small flexural rigidity and do not flow out the penetrating water. In this paper, FRP corrugate sheet was proposed. The tunnel lining was made by FRP corrugate sheet that supported the lining concrete in the tunnel and flowed the water and the moisture swept on the tunnel surface. The FRP corrugate sheet was supported by the anchor bolts. In numerical analyses, the finite element degenerate shell was adopted to represent the FRP sheet behavior. Assuming that the concrete liner at the top was fallen down, the peeled concrete was applied as the load. From the numerical analysis, the effectiveness of the FRO corrugate sheet was confirmed.
文摘The nanoporous thermal insulating material was prepared by using fumed silica,SiC powder and glass fiber as starting materials,the appropriate thickness of the nanoporous thermal insulating material lined in ladle was discussed by the simulation method,and the effect of its application as ladle lining was investigated.The results show that the thermal conductivity of the nanoporous thermal insulating material prepared in composition of fumed silica： SiC powder： glass fiber =75： 20：5 （in mass） is 0.023 W · m^-1 · K^-1 at 1 000 ℃,the appropriate thickness of the nanoporous thermal insulating material lined in ladle is ≤ 5 mm and the average temperature of the ladle outside surface when lined with the nanoporous thermal insulating material is 95 ℃ lower than that with the ordinary thermal insulating material.
文摘“Are you dead?”It's not a morbid joke-it's the literal translation of the name of Chinese app Sileme,which went viral around the country in early January.However,amid public controversy over its unsettling connotations,the development team rebranded the app as Demumu on January 14,be-fore it was removed from the app stores of Apple and Android on January 15.
基金supported by the National Key Research and Development Program of China(Grant Nos.2021YFB2600800&2023YFB2604005)the National Key Research and Development 451 Program of China(Grant No.2021YFC3100803).
文摘Multi-layer linings have been widely used in deep rheological soft rock tunnels for the excellent performance in preventing large-deformation hazards.Previous studies have focused on the bearing capability of multi-layer lining,however,its failure characteristics and synergistic load-bearing mechanisms under high geo-stress are still unclear.To fill the gap,three-dimensional geomechanical model tests were conducted and synergistic mechanisms were analysed in this study.The model test was divided into normal loading,excavat-ing,and overloading stages.The surrounding rock deformation was monitored by using an improved high-precise extensometer mea-surement system.Results show that the largest radial deformation appears on the sidewall,followed by the floor and vault during the excavating stage.The relative convergence deformation of sidewalls springing reaches 1.32 mm.The failure characteristics of the multi-layer linings during the overloading stage undergo an evolution of stability,crack initiation,local failure,and collapse,with a safety factor of 1.0-1.6,1.6-2.0,and 2.0-2.2,respectively.The synergistic load-bearing mechanism analysis results suggest that the early stiffness and late yielding deformation capacity of large deformation support measures play important roles in stability maintenance both in the construction and operation of deep soft rock tunnels.Therefore,the combination of yielding support or a compressible layer with reinforced support is recommended to mitigate the effect of the high geo-stress.
基金supported by the National Natural Science Foundation of China(Grant No.52478409)Shanghai Sci-tech Co-research Program Qualification Project(No.23DZ1202903).
文摘The construction of new tunnels induces additional/unloading pressures on existing tunnels,subsequently affecting structural integrity.To assess tunnel response,a full-scale multiring test was conducted,simulating water/soil and additional/unloading pressure from a new undercrossing tunnel.Key parameters analyzed included additional/unloading pressure,tunnel axis distance,longitudinal forces,and loading levels to evaluate structural deformations and joint behavior.Results showed that additional/unloading forces significantly impact structural ring convergence during tunnel crossing stage.These forces vary nonlinearly with distance from the crossing point,but their influence is linear.Further,joint opening and dislocation not only depend on external load but also on the staggering effect and segment geometry.Reducing the tunnel axis distance meaningfully upsurges unloading forces,leading to higher strains at joints and the segment body.Longitudinal force,directly proportional to the staggering effect,reduces structural deformations;for instance,even a 1%force mitigates up to 32.05%joint dislocation.Lifecycle analysis revealed the tunnel crossing stage is far more vulnerable than the construction/operation stage,and tunnel axis distances of twice or more of the diameter can be considered safe.This study provides practical insights for engineers to mitigate risks during tunnel crossings and enhances safety guidelines for life cycle management.
基金supported by the National Key R&D Program of China(No.2023YFC3806705)the National Natural Science Foundation of China(Grant Nos.52038008 and 52378408)+1 种基金the Science and Technology Innovation Plan of Shanghai Science and Technology Commission(No.22dz1203004)the Science and Technology Project of State Grid Corporation of China(No.5200-202417104A-1-1-ZN).
文摘Steel fiber reinforced concrete-reinforced concrete(SFRC-RC)composite linings are popular in shield tunnel construction due to exceptional strength and waterproofing properties.Non-destructive testing methods are essential for assessing the quality of these linings and ensuring tunnel construction safety.This study investigates the potential and parameters of ground penetrating radar(GPR)detection for the composite linings,using the Deep Tunnel Sewerage System-Phase 2 project in Singapore as a case study.The gprMax simulations incorporated the random distribution and precise parameters of steel fibers to conduct preliminary frequency selection studies.The structural setup of the model experiments mirrored that of the actual tunnel,allowing for an analysis of GPR penetration capabilities at various frequencies.Field testing provided authentic GPR data,validating conclusions drawn from simulations and model experiments and examining GPR power attenuation patterns.Findings indicate that GPR is effective for the quality detection of composite linings.The optimal frequency for detecting SFRC-RC composite linings is 300 MHz,which resolves the interfaces of different layered media.Based on single-parameter exponential and power function fitting,empirical formulas for power attenuation quantitatively characterize GPR signal attenuation in SFRC-RC composite linings.This paper offers valuable references for GPR detection of SFRC-RC composite linings.
文摘Metro(subway)is an advanced public transport infrastructure system in urban areas with high capacity.The traffic operation of a metro is not affected by other vehicle traffic thanks to underground tunnels.With these benefits metro lines are preferred to solve the traffic problem in urbanized cities such as Istanbul,which is the focus of this study.Metro projects require huge amounts of budgets to be built.Putting these projects into service in targeted time is of great importance.The objective of this study is to minimize total metro construction project time by utilizing fiber reinforcement in tunnel linings.In this research,using fiber reinforcement to construct primary(initial)tunnel linings and secondary(final)tunnel linings of the metro projects are analyzed in terms of project duration.After comparison of two railway tunnel projects,evaluations and observations of a completed metro project revealed that using fiber reinforcement for either the primary lining or the final lining of tunnels reduces construction time of metro station tunnels by 25%.In addition,using fiber reinforcement to construct both the final lining and the primary lining of tunnels reduces construction time of the metro station tunnels and the whole metro project by 47% and 22%,respectively.The results of this study can be useful for completing challenging metro projects and putting it into service within the targeted time.
基金Supported by Ningbo NSF(No.2021J234)Zhejiang Provincial Philosophy and Social Sciences Planning Project(No.24NDJC057YB)。
文摘The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isomers,such as boiling point,of formation are found to be better measured by the ABS index than by the Randi,atom-bond connectivity(ABC),and sum-connectivity(SC)indices.One important source of information for researching the molecular structure is the bounds for its topological indices.The extrema of the ABS index of the line,total,and Mycielski graphs are calculated in this work.Moreover,the pertinent extremal graphs were illustrated.
基金supported by a Ph.D.scholarship from the YLSY program of the Republic of Turkiye,Ministry of National Educationfunded by Fight for Sight UK,grant reference#5183/5184。
文摘Glaucoma is characterized by chronic progressive optic nerve damage and retinal ganglion cell death.Although extensive research has been conducted on neuroprotection for retinal ganglion cells,there is still no treatment for clinical use.Recent evidence shows that extracellular vesicles isolated from a variety of stem cells are efficacious in retinal ganglion cell neuroprotection.In this study,we tested the novel extracellular vesicle source of the retinal progenitor R-28 cell line in vitro and in vivo.We isolated and characterized extracellular vesicles from R-28 cells and tested their therapeutic efficacy in terms of retinal ganglion cell survival in vitro and in an in vivo glaucoma model,measuring retinal ganglion cell survival and preservation of their axons.Additionally,we tested extracellular vesicles for their neuroprotective capacity in retinal ganglion cells differentiated from human embryonic stem cells.Finally,we investigated miRNA changes in retinal ganglion cells with R-28 extracellular vesicle treatment,and predicted possible pathways that may be modulated.R-28 extracellular vesicles improved retinal ganglion cell survival but failed to preserve axons significantly.Moreover,the results also illustrated the neuroprotection of R-28 extracellular vesicles on human retinal ganglion cells.Finally,we also showed changes in hsa-miRNA-4443,hsa-miRNA-216a-5p,hsa-let-7e-5p,hsa-miRNA-374b-5p,hsa-miRNA-331-3p,and hsa-miRNA-421 expressions,which may have neuroprotective potential on retinal ganglion cell degeneration.This study will pave the way for miRNA and extracellular vesicle-based neuroprotective therapies for glaucoma.
基金supported by the National Natural Science Foundation of China(Grant No.52475543)Natural Science Foundation of Henan(Grant No.252300421101)+1 种基金Henan Province University Science and Technology Innovation Talent Support Plan(Grant No.24HASTIT048)Science and Technology Innovation Team Project of Zhengzhou University of Light Industry(Grant No.23XNKJTD0101).
文摘Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in operator workloads and significantly increase the complexity of scheduling.To address this challenge,this study investigates the Aircraft Pulsating Assembly Line Scheduling Problem(APALSP)under skilled operator allocation,with the objective of minimizing assembly completion time.A mathematical model considering skilled operator allocation is developed,and a Q-Learning improved Particle Swarm Optimization algorithm(QLPSO)is proposed.In the algorithm design,a reverse scheduling strategy is adopted to effectively manage large-scale precedence constraints.Moreover,a reverse sequence encoding method is introduced to generate operation sequences,while a time decoding mechanism is employed to determine completion times.The problem is further reformulated as a Markov Decision Process(MDP)with explicitly defined state and action spaces.Within QLPSO,the Q-learning mechanism adaptively adjusts inertia weights and learning factors,thereby achieving a balance between exploration capability and convergence performance.To validate the effectiveness of the proposed approach,extensive computational experiments are conducted on benchmark instances of different scales,including small,medium,large,and ultra-large cases.The results demonstrate that QLPSO consistently delivers stable and high-quality solutions across all scenarios.In ultra-large-scale instances,it improves the best solution by 25.2%compared with the Genetic Algorithm(GA)and enhances the average solution by 16.9%over the Q-learning algorithm,showing clear advantages over the comparative methods.These findings not only confirm the effectiveness of the proposed algorithm but also provide valuable theoretical references and practical guidance for the intelligent scheduling optimization of aircraft pulsating assembly lines.
文摘Poly-and perfluoroalkyl substances(PFAS),including perfluorooctanoic acid(PFOA)and perfluorooctane sul-fonate(PFOS),are persistent environmental pollutants with potential toxicological effects on human health.The aim of this study was to investigate the impact of PFOS and PFOA on the effectiveness of selected drugs used in the treatment of prostate cancer based on in vitro tests on cell lines.Three cell lines were used in the study:two human prostate cancer cells(DU-145 and PC3)and one human normal prostate cell line(PNT1A).Using dose-response experiments,it was observed that PFAS had differential effects on cancer and normal cells.At low concentrations,PFOA and PFOS stimulated the proliferation of cancer cells,particularly PC3,while higher concentrations led to reduced viability.In normal cells,PFOS exhibited greater cytotoxicity compared to PFOA.Furthermore,PFOS enhanced docetaxel cytotoxicity in PC3 cells but reduced its efficacy in DU-145 cells.Similarly,PFOA diminished cabazitaxel effectiveness in DU-145 cells,suggesting PFAS-drug interactions may depend on the cell type,drug,and PFAS concentration.Results suggest that PFAS may influence cellular processes through receptor-mediated pathways,oxidative stress modulation,and protein binding,altering drug bioavailability and cellular uptake.The study also highlights the non-monotonic dose-response relationships observed in PFAS-treated cells.These findings raise concerns about the potential risks associated with PFAS exposure,particularly in the context of cancer treatment.Future studies should focus on long-term,low-dose PFAS exposure,the use of primary cells,and the molecular mechanisms driving these interactions to better inform therapeutic strategies.
基金funded by the Key R&D Program of Yangling Seed Industry Innovation,China(Ylzy-xm-02)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2021QNRC001)。
文摘Thinopyrum ponticum(2n=10×=70),a wild relative of common wheat(Triticum aestivum L.),is considered an invaluable genetic resource for wheat improvement due to its abundance of genes conferring resistance to biotic and abiotic stresses.This study focused on the CH97 line,derived from the BC1F7 progeny of a cross between wheat cv.7182 and Th.ponticum.Cytological evidence showed that CH97 has 42 chromosomes,forming 21 bivalents at meiotic metaphase I,with the bivalents subsequently separating and moving to opposite poles during meiotic anaphase I.Through a combination of fluorescence in situ hybridization(FISH),genomic in situ hybridization(GISH),multicolor GISH(mc-GISH),and liquid array analysis,it was determined that CH97 comprises 40 wheat chromosomes and two alien chromosomes from the Ee genome of Th.ponticum,featuring the absence of a pair of 5D chromosomes and variations in 1B,6B,and 7B chromosomes.These findings confirm that CH97 is a stable wheat-Th.ponticum 5E(5D)alien disomic substitution line.Inoculation experiments revealed that CH97 exhibits high resistance to wheat powdery mildew and stripe rust throughout the growth period,in contrast to the highly susceptible common wheat parent 7182.Compared to 7182,CH97 displayed improvements in thousand-kernel weight and kernel length.Additionally,utilizing specific-locus amplified fragment sequencing(SLAF-seq)technology,chromosome 5E-specific molecular markers were developed and validated,achieving a 33.3% success rate,facilitating marker-assisted selection for disease resistance in wheat.Overall,the CH97 substitution line,with its resistance to diseases and improved agronomic traits,represents valuable new germplasm for wheat chromosome engineering and breeding.
