Scutellaria barbata attenuates diabetic retinopathy by preventing retinal inflammation and the decreased expression of tight junction protein

AIM： To observe the attenuation of ethanol extract of Herba Scutellaria barbata （SE） against diabetic retinopathy （DR） and its engaged mechanism. METHODS： C57BL/6J mice were intraperitoneally injected with streptozotocin （STZ, 55 mg/kg） for 5 consecutive days to induce diabetes, The diabetic mice were orally given with SE （100, 200 mg/kg） for lmo at lmo after STZ injection. Blood-retinal barrier （BRB） breakdown was detected by using Evans blue permeation assay. Real-time polymerase chain reaction （RT-PCR）, Western blot and immunofiuorescence staining were used to detect mRNA and protein expression. Enzyme-linked immunosorbent assay （ELISA） was used to detect serum contents of tumor necrosis factor-e （TNF-a） and interleukin （IL）-II. RESULTS： SE （100, 200 mg/kg） reversed the breakdown of BRB in STZ-induced diabetic mice. The decreased expression of retinal claudin-1 and claudin-19, which are both tight junction （T J） proteins, was reversed by SE. SE decreased the increased serum contents and retinal mRNA expression of TNF-a and IL-113. SE also decreased the increased retinal expression of intercellular cell adhesion molecule-1 （ICAM-1）. SE reduced the increased phosphorylation of nuclear factor kappa B （NFKB） p65 and its subsequent nuclear translocation in retinas from STZ- induced diabetic mice. Results of Western blot and retinal immunofluorescence staining of ionized calcium-binding adapter molecule 1 （Ibal） demonstrated that SE abrogated the activation of microglia cells in STZ-induced diabetic mice. CONCLUSION： SE attenuates the development of DR by inhibiting retinal inflammation and restoring the decreased expression of TJ proteins including claudin-1 and claudin-19.

对未定型炎症性肠病的认知与处理

未定型炎症性肠病是指临床上暂时无法明确诊断和分型的结肠炎患者,其具备炎症性肠病相关临床特征,但不足以诊断为溃疡性结肠炎或克罗恩病。随着时间推移,大部分未定型炎症性肠病患者可确诊为溃疡性结肠炎或克罗恩病,治疗上可采用升阶梯治疗方法。本文阐述了未定型炎症性肠病的临床特点、诊断及治疗方法。

谷胱甘肽在肿瘤细胞发生铁死亡过程中的作用研究

铁死亡是近年发现的一种铁依赖性脂质过氧化和活性氧(reactive oxygen species,ROS)诱导的调节性细胞死亡,其发生过程中伴有ROS水平升高和抗氧化系统的下降--如酶抗氧化剂中谷胱甘肽过氧化物酶和非酶抗氧化剂中谷胱甘肽等.谷胱甘肽是细胞内普遍存在的低分子量抗氧化剂,其稳态水平依赖于所需氨基酸前体吸收速率、酶活性、谷胱甘肽二硫化物的回收以及氧化还原之间的平衡等.目前,靶向谷胱甘肽代谢已被广泛研究用于癌症治疗,与组合疗法相比,作为单一治疗策略的谷胱甘肽耗竭产生了显著的治疗效果.因此,深入认识谷胱甘肽在铁死亡发生过程中的作用,将为癌症治疗提供新的思路和方向.

Potential model for differential diagnosis between Crohn's disease and primary intestinal lymphoma

AIM To evaluate the usefulness of different parameters to differentiate Crohn's disease(CD) from primary intestinal lymphoma(PIL).METHODS The medical records of 85 patients with CD and 56 patients with PIL were reviewed retrospectively. Demographic, clinical, laboratory, endoscopic, and computed tomographic enterography(CTE) parameters were collected. The univariate value of each parameter was analyzed. A differentiation model was established by pooling all the valuable parameters. Diagnostic efficacy was analyzed, and a receiver operating characteristic(ROC) curve was plotted.RESULTS The demographic and clinical parameters that showed significant values for differentiating CD from PIL included age of onset, symptom duration, presence of diarrhea, abdominal mass, and perianal lesions(P < 0.05). Elevated lactate dehydrogenase and serum β2-microglobulin levels suggested a PIL diagnosis(P < 0.05). The endoscopic parameters that showed significant values for differentiating CD from PIL included multiple-site lesions, longitudinal ulcer, irregular ulcer,and intraluminal proliferative mass(P < 0.05). The CTE parameters that were useful in the identification of the two conditions included involvement of ≤ 3 segments, circular thickening of the bowel wall, wall thickness > 8 mm, aneurysmal dilation, stricture with proximal dilation, "comb sign", mass showing the "sandwich sign", and intussusceptions(P < 0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the differentiation model were 91.8%, 96.4%, 93.6%, 97.5%, and 88.5%, respectively. The cutoff value was 0.5. The area under the ROC curve was 0.989.CONCLUSION The differentiation model that integrated the various parameters together may yield a high diagnostic efficacy in the differential diagnosis between CD and PIL.

Structural characteristics of the KPR-CBR triple-junction inferred from gravity and magnetic interpretations,Philippine Sea Plate

The intersection of the Kyushu-Palau Ridge(KPR)and the Central Basin Rift(CBR)of the West Philippine Basin(WPB)is a relic of a trench-trench-rift(TTR)type triple-junction,which preserves some pivotal information on the cessation of the seafloor spreading of the WPB,the emplacement and disintegration of the proto-Izu-Bonin-Mariana(IBM)Arc,and the transition from initial rifting to steady-state spreading of the Parece Vela Basin(PVB).However,the structural characteristics of this triple-junction have not been thoroughly understood.In this paper,using the newly acquired multi-beam bathymetric,gravity,and magnetic data obtained by the Qingdao Institute of Marine Geology,China Geological Survey,the authors depict the topographic,gravity,and magnetic characteristics of the triple-junction and adjacent region.Calculations including the upward continuations and total horizontal derivatives of gravity anomaly are also performed to highlight the major structural features and discontinuities.Based on these works,the morphological and structural features and their formation mechanisms are analyzed.The results show that the last episode amagmatic extension along the CBR led to the formation of a deep rift valley,which extends eastward and incised the KPR.The morphological and structural fabrics of the KPR near and to the south of the triple-junction are consistent with those of the western PVB,manifesting as a series of NNE-SSW-and N-S-trending ridges and troughs,which were produced by the extensional faults associated with the initial rifting of the PVB.The superposition of the above two reasons induced the prominent discontinuity of the KPR in deep and shallow crustal structures between 15°N‒15°30′N and 13°30′N‒14°N.Combined with previous authors’results,we propose that the stress produced by the early spreading of the PVB transmitted westward and promoted the final stage amagmatic extension of the CBR.The eastward propagation of the CBR destroyed the KPR,of which the magmatism had decayed or ceased at that time.The destruction mechanism of the KPR associated with the rifting of the PVB varies along strike the KPR.Adjacent to the triple-junction,the KPR was destroyed mainly due to the oblique intersection of the PVB rifting center.Whereas south of the triple-junction,the KPR was destroyed by the E-W-directional extensional faulting on its whole width.

Geochemistry and genesis of the Nadun Nb-enriched arc basalt in the Duolong mineral district,western Tibet:Indication of ridge subduction

The Duolong mineral district in western Tibet is one of the largest porphyry Cu–Au deposit fields with significant metallogenic potential in China.Its tectonic environment relevant to Early Cretaceous Cu–Au mineralization remains controversial.Here we report new whole-rock major and trace element,and Sr-Nd-Hf-Pb isotopic data for the newly discovered basalt in the Nadun area,Duolong mineral district,to decipher their genesis and further constrain the tectonic environment.A contemporaneous rhyolite sample interbedded with the basalt in the lower part of the volcanic section in the Nadun area yields an LA-ICP-MS zircon U–Pb age of 122.5±1.2 Ma.The basalt samples exhibit high-K calc-alkaline/shoshonite properties and are enriched in high field strength elements,e.g.,high Ti O_(2)(1.43–1.79 wt.%)and Nb(14.6–19.5 ppm)contents,with high Nb/La ratios(0.4–0.6),which are compositionally comparable to those of Nb-enriched arc basalts(NEABs).The(^(87) Sr/^(86) Sr)iratios of 0.7052 to 0.7056,negative eNd(t)(-0.7 to-0.2)and eHf(t)values(+6.0 to+6.5),and high(^(206) Pb/^(204)Pb)i,(^(207) Pb/^(204)Pb)i,(^(208) Pb/^(204)Pb)iand ratios(18.522 to 18.561,15.641 to 15.645 and 38.679 to 38.730,respectively)suggest that the Nadun NEABs are more enriched than those of the island arc basalts(IABs)in the area.The slightly enriched radiogenic isotopes for the Nadun NEABs indicate that the subducting sediments play an important role in the source.Furthermore,their high Nb,Ti,and Cu contents indicate that the source mantle wedge was metasomatized by slab melts.The Nadun NEAB and other coeval magmatic rocks in the Duolong mineral district,including adakite,OIB-like basalt,MORB-type basalt,A-type rhyolite,and common IAB,are typical rock assemblages of ridge subduction.We infer that the Duolong mineral district were formed by ridge subduction in the Early Cretaceous.

Scutellarein alleviates the dysfunction of inner blood-retinal-barrier initiated by hyperglycemia-stimulated microglia cells

AIM:To investigate the alleviation of scutellarein(SN)against inner blood-retinal-barrier(iBRB)dysfunction in microglia cells stimulated by hyperglycemia and to elucidate the engaged mechanism.METHODS:Microglia BV2 cells were stimulated by using 25 mmol/L D-glucose.The same concentration of mannitol(25 mmol/L)was applied as an isotonic contrast.Real-time PCR,Western-blot assay and immunofluorescence staining assay was performed.The dysfunction of iBRB in vitro was detected by using transendothelial electrical resistance(TEER)assay.Additionally,the leakage of fluorescein isothiocyanate(FITC)-conjugated dextran(70 kDa)was detected.RESULTS:SN abrogated microglia BV2 cells activation and reduced the phosphorylated activation of extracellular signal-regulated protein kinase(ERK)1/2.SN also decreased the transcriptional activation of nuclear factorκB(NFκB)and the elevated expression of tumor necrosis factorα(TNFα),interleukin(IL)-6 and IL-1βin BV2 cells treated with D-glucose(25 mmol/L).SN attenuated iBRB dysfunction in human retinal endothelial cells(HRECs)or choroid-retinal endothelial RF/6 A cells when those cells were treated with TNFα,IL-1βor IL-6,or co-cultured with microglia cells stimulated by D-glucose.Moreover,SN restored the decreased protein expression of tight junctions(TJs)in TNFα-treated HRECs and RF/6 A cells.CONCLUSION:SN not only alleviate iBRB dysfunction via directly inhibiting retinal endothelial injury caused by TNFα,IL-1βor IL-6,but also reduce the release of TNFα,IL-1βand IL-6 from microglia cells by abrogating hyperglycemia-mediated the activation of microglia cells.

Formation and elimination of burst phenomenon in ultrasonic-assisted resistance brazing

A two-step ultrasonic-assisted brazing method and its associated apparatus were developed to make 6063 aluminum alloys joints with Al-Si-Mg filler metal. The burst phenomenon and the effect of ultrasonic direction and time, as well as the welding joint geometry on the burst phenomenon were investigated. The results show that the burst phenomenon occurs in the liquid filler metal under the effects of high current density, heat, and interaction force. The burst phenomenon is eliminated when the oxide film on the edge of the cross-section of the two parent metals is removed with more than or equal to 6 s ultrasonic time. A model of formation and elimination for burst was proposed, through which the blasting phenomenon can be controlled by changing the ultrasonic time and the geometrical shape of the welded joint.

A low-cost and high-performance technique for adaptive optics static wavefront correction

Non-Common Path Error(NCPE) is one of the factors that limit an Adaptive Optics(AO)system from delivering ultra-high performance. To correct the NCPE associated static aberration, we propose a simple but robust and high-performance pupil-plane based wavefront measurement and correction technique, which can copy a single-mode fiber generated perfect wavefront to the AO system via an iteration optimization process, and the NCPE can be effectively corrected by directly commanding the Deformable Mirror(DM) of the AO system. Compared with the previous focal-plane based approach that uses focal plane based Point Spread Function(PSF) for correction evaluation, the pupil-plane based approach can be reliably and rapidly converged to a global optimization result and provides better performance, in particular for an AO system with a large initial static wavefront error. This technique we proposed can be implemented in astronomical AO systems where extremely high performance is required.

Computed tomography perfusion and computed tomography angiography for prediction of clinical outcomes in ischemic stroke patients after thrombolysis

Cerebral blood perfusion and cerebrovascular lesions are important factors that can affect the therapeutic efficacy of thrombolysis.At present,the majority of studies focus on assessing the accuracy of lesion location using imaging methods before treatment,with less attention to predictions of outcomes after thrombolysis.Thus,in the present study,we assessed the efficacy of combined computed tomography（CT） perfusion and CT angiography in predicting clinical outcomes after thrombolysis in ischemic stroke patients.The study included 52 patients who received both CT perfusion and CT angiography.Patients were grouped based on the following criteria to compare clinical outcomes：（1） thrombolytic and non-thrombolytic patients,（2） thrombolytic patients with CT angiography showing the presence or absence of a vascular stenosis,（3） thrombolytic patients with CT perfusion showing the presence or absence of hemodynamic mismatch,and（4） different CT angiography and CT perfusion results.Short-term outcome was assessed by the 24-hour National Institution of Health Stroke Scale score change.Long-term outcome was assessed by the 3-month modified Rankin Scale score.Of 52 ischemic stroke patients,29 were treated with thrombolysis and exhibited improved short-term outcomes compared with those without thrombolysis treatment（23 patients）.Patients with both vascular stenosis and blood flow mismatch（13 patients） exhibited the best short-term outcome,while there was no correlation of long-term outcome with CT angiography or CT perfusion findings.These data suggest that combined CT perfusion and CT angiography are useful for predicting short-term outcome,but not long-term outcome,after thrombolysis.

(Sn_(1-x)Zn_(x))_(57)(In_(0.78)Bi_(0.22))_(43)低熔点无铅焊料的微观结构表征

为了寻求一种应用于三维集成电路低温焊接的无铅焊料,基于多组元混合的概念设计并表征(Sn_(1-x)Zn_(x))_(57)(In_(0.78)Bi_(0.22))_(43)(x=0.10,0.15,0.20,摩尔分数,%)四元合金。采用扫描电子显微镜、X射线衍射仪和差示扫描量热仪研究合金的显微组织、热性能和润湿性。结果表明,合金由金属间化合物BiIn_(2)、In_(0.2)Sn_(0.8)和富Zn固溶体组成。随着Zn添加量的增加,BiIn_(2)和富Zn相的体积分数增加。合金的熔点低至70℃,源自低熔点金属间化合物In_(0.2)Sn_(0.8)和BiIn_(2)的形成;合金具有良好的润湿性,润湿角约为40°。在合金和Cu板的界面结合处形成一种薄而坚韧的Cu_(5)Zn_(8)层,提高焊点可靠性。研究表明,通过多组元混合概念设计合金可以有效提高焊料的焊接性能。

Identification and evolution of tectonic units in the Philippine Sea Plate

The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and eight third-order tectonic units by summarizing the marine geological,geophysical,and submarine geomorphological data of the Philippine Sea Plate collected for years and referring to the seafloor spreading theory and the trench-arc-basin system.The two second-order tectonic units are the West Philippine Sea block and the Izu-Bonin-Mariana arc-basin system.The former includes the West Philippine Basin,the Huatung Basin,the Daito Basin,and the Palau Basin,while the latter consists of the Kyushu-Palau Ridge,the Shikoku-Parece Vela Basin,the Izu-Bonin Arc,and the Mariana Arc.Furthermore,this study concludes that the Philippine Sea Plate has undergone three stages of tectonic evolution,namely the early stage of the evolution of marginal basins with Cretaceous basement(Early Cretaceous),the middle stage of the spreading of the West Philippine Basin(Eocene),and the late stage of the subduction of the Izu-Bonin-Mariana arc-basin system(Oligocene-present).The Kyushu-Palau Ridge is a window to discover the tectonic evolution of the Philippine Sea Plate due to its unique geographical location.

Prediction of the mechanism of prostate prescription Ⅰ in the treatment of chronic prostatitis based on integrative pharmacology of traditional Chinese medicine

Objective:To investigate potential mechanism of Prostate prescriptionⅠin the treatment of chronic prostatitis based on integrated pharmacology.Methods:with the help of TCMIP,the effective compounds of Prostate prescriptionⅠwere screened,and the potential target database of Prostate prescriptionⅠwas established by using the target prediction function of TCMIP.Based on the Human Phenotype Ontology database and protein interaction network(PPI)database,the disease target of CP was identified and the target interaction network was constructed;Through the GO function analysis and KEGG pathway enrichment analysis of the candidate targets,combined with Chinese and foreign literature studies to predict the potential Signaling pathway of Prostate prescriptionⅠin the treatment of CP.Results:79 effective compounds of Prostate prescriptionⅠexerted its effect on 33 targets through 11 pathways.Conclusion:Clinical efficacy of Prostate prescriptionⅠon CP may be reflected in antiinflammation and anti-tumor,cell metabolism,immune regulation,neuroregulation and so on.

Bai Hu Ren Shen Soup promotes autophagy in the pancreas tissue of diabetic rats by increasing the level of autophagy protein LC3 and decreasing the level of autophagy protein p62

Objective:To investigate the therapeutic effect of Bai Hu Ren Shen Soup(BHRSS)on type 2 diabetes mellitus(T2DM)rats and explore whether its therapeutic effect is achieved by promoting autophagy in the pancreas tissue of T2DM rats.Methods:Thirty male standard deviation rats were equally divided into normal control group,T2DM group and BHRSS group.Firstly,the therapeutic effect of BHRSS on T2DM was evaluated by biochemical indices in serum and pathological changes in the pancreas tissue of rats in each group after modeling and medication.Then,the levels of microtubule-associated protein 1 light chain 3(LC3)protein and p62 protein in the pancreas tissue of rats in each group after BHRSS intervention were detected by Western blot.Results:BHRSS intervention significantly reduced the levels of blood sugar,liver and kidney function,and other related biochemical indices in the serum of T2DM rats,and effectively improved the pathological changes in the pancreas tissue of T2DM rats.In addition,Western blot results showed that the expression levels of autophagy-related protein LC3 protein in the pancreas tissue of rats were increased,and the expression level of p62 protein was decreased after BHRSS intervention.Conclusion:BHRSS has a clear therapeutic effect on T2DM model rats,which may be related to that increase of autophagy protein LC3 and the decrease of p62 protein level in the pancreas tissue.

Turbulent heat fluxes in the North Water Polynya and ice estimated based on ASRv2 data and their impact on cloud

The presence or absence of sea ice introduces a substantial perturbation to surface-atmosphere energy exchanges.Comprehending the effect of varying sea ice cover on surface-atmosphere interactions is an important consideration for understanding the Arctic climate system.The recurring North Water Polynya(NOW)serves as a natural laboratory for isolating cloud responses to a rapid,near-step perturbation in sea ice.In this study,we employed high-resolution Arctic System Reanalysis version 2(ASRv2)data to estimate turbulent heat fluxes over the NOW and nearby sea ice(NSI)area between 2005/2006 and 2015/2016.The results indicate that the average turbulent heat fluxes in the polynya are about 87%and 86%higher than in the NSI area over the 10 years during the entire duration of the polynya and during polar night,respectively.Enhanced turbulent heat fluxes from the polynya tend to produce more low-level clouds.The relationship between the polynya and low cloud in winter was examined based on Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations(CALIPSO).The low-cloud fraction(0-2 km)was about 7%-34%larger over the polynya than the NSI area,and the ice water content below 200 m was about 250%-413%higher over the former than the latter.The correlation between cloud fraction and turbulent heat fluxes in the polynya peaks around the altitude of 200-300 m.These results suggest that the NOW affects the Arctic boundary layer cloudiness and structure in wintertime.Furthermore,higher horizontal resolution reanalysis data can advance our understanding of the cloud-polynya response.

Photoinduced copper-catalyzed alkoxyl radical-triggered ring-expansion/aminocarbonylation cascade

A photoinduced copper-catalyzed alkoxyl triggered C-C bond cleavage/aminocarbonylation cascade is presented.Through adjusting the structure of alkoxyl radical precursors,functionalized lactones and ketoamides were synthesized with good yields and excellent functional group tolerance under redox-neutral conditions.Notably,this protocol enables the integration of lactone fragments with many amine drugs and drug fragments.

On the two-layer high-level Green-Naghdi model in a general form

The traditional high-level Green-Naghdi(HLGN)model,which uses the polynomial as the shape function to approximate the variation of the horizontal-and vertical-velocity components along the vertical direction for each-fluid layer,can accurately describe the large-amplitude internal waves in a two-layer system for the shallow configuration(h_(2)/λ■1,h_(1)/λ■1).However,for the cases of the deep configuration(h_(2)/λ■1,h_(1)/λ=O(1)),higher-order polynomial is needed to approximate the variation of the velocity components along the vertical direction for the lower-fluid layer.This,however,introduces additional unknowns,leading to a significant increase in computational time.This paper,for the first time,derives a general form of the HLGN model for a two-layer fluid system,where the general form of the shape function is used during the derivation.After obtaining the general form of the two-layer HLGN equations,corresponding solutions can be obtained by determining the reasonable shape function.Large-amplitude internal solitary waves in a deep configuration are studied by use of two different HLGN models.Comparison of the two HLGN models shows that the polynomial as the shape function for the upper-fluid layer and the production of exponential and polynomial as the shape function for the lower-fluid layer is a good choice.By comparing with Euler’s solutions and the laboratory measurements,the accuracy of the two-layer HLGN model is verified.

湿热环境对T700/MTM46复合材料层合板拉-拉疲劳性能和疲劳可靠寿命的影响（英文）

目的:碳纤维复合材料的疲劳特性对航空结构的安全性和可靠性有很大的影响,而湿热环境对复合材料性能的退化作用较大.本文针对湿热环境对碳纤维复合材料层合板的拉-拉疲劳性能和疲劳可靠寿命的影响进行研究,为碳纤维复合材料在实际湿热环境中的应用提供参考.创新点:1.通过实验分析得到碳纤维复合材料层合板在吸湿过程中的损伤演化过程;2.采用实验和理论分析的方法,研究湿热环境对碳纤维复合材料层合板拉-拉疲劳性能和疲劳可靠寿命的影响.方法:1.通过吸湿实验,观测分析得到碳纤维复合材料层合板在湿热老化过程中的损伤演化过程;2.通过疲劳试验,研究湿热环境下碳纤维复合材料的疲劳损伤演化过程、刚度退化规律和损伤失效模式;3.通过理论分析,采用疲劳可靠寿命预测模型,得到湿热环境下碳纤维复合材料的疲劳可靠寿命.结论:1.T700/MTM46复合材料层合板在吸湿过程中,出现了微孔和微脱层等损伤,但比疲劳过程中产生的损伤要小得多;2.与常温环境相比,湿热环境下实验件的刚度退化曲线的变化趋势保持一致,但刚度下降幅度增大;3.与常温环境相比,湿热环境下实验件的疲劳极限降低约6%,疲劳损伤模式相似,但在相同疲劳循环数下的损伤程度加剧;4.在湿热环境作用下,实验件的疲劳可靠寿命大大降低.

On solitary wave in nonuniform shear currents

In this paper,steady solutions of solitary waves in the presence of nonuniform shear currents are obtained by use of the high-level Green-Naghdi(HLGN)model.We focus on large-amplitude solitary waves in strong opposing shear currents.The linear-type currents,quadratic-type currents and cubic-type currents are considered.In particular,the wave speed,wave profile,velocity field,particle trajectories and vorticity distribution are studied.It is demonstrated that presence of the nonuniform shear current modifies the velocity field and vorticity field of the solitary wave.

Effect of low-temperature ausforming on bainitic transformation and mechanical properties in ultrahigh-strength bainitic steel

Low-temperature ausforming(LT-AF)prior to bainitic transformation leads to a noticeable acceleration of bainitic transformation kinetics;however,the effect of LT-AF on the retained austenite(RA)features and the resulting mechanical properties is still unclear.LT-AF was applied to ultrahigh-strength bainitic steel before austempering.The deformation behavior and the resulting dislocation substructures were investigated by thermomechanical simulator and transmission electron microscopy(TEM).The planar dislocation structures produced during deformation at 350℃ accelerate the bainitic transformation kinetics during isothermal holding.The effect of LT-AF on the bainitic transformation kinetics and the features of RA was elucidated via dilatometer measurement,TEM,scanning electron microscopy,and X-ray diffraction.It is observed that LT-AF not only retains more RA content but also facilitates improved RA stability.This trend is mainly due to the large amounts of planar dislocations in RA and bainitic laths inherited from undercooled austenite caused by LT-AF,the decrease in bainitic sheaves size,and the increase in filmy RA content compared to the sample without ausforming.A large fraction of filmy RA with high stability and the refinement of bainitic sheaves obtained by LT-AF remarkably enhance the strain hardening capacity and achieve significantly better ductility compared to the directly austempered sample.