Differences in hydrocarbon accumulation and controlling factors of slope belt in graben basin: A case study of Pinghu Slope Belt in the Xihu sag of the east China Sea Shelf basin(ECSSB)

The Pinghu slope belt in the Xihu sag of the East China Sea Shelf Basin(ECSSB) is a crucial hydrocarbon production area in eastern China. However, due to the complex geological conditions, publications have lacked comprehensive research on the spatial-temporal coupling relationships of primary factors that impact hydrocarbon accumulation in the Pinghu slope belt. Furthermore, the hydrocarbon distribution patterns and the controlling factors across different study areas within the same slope belt are not yet fully understood. This study extensively utilized three-dimensional seismic data, well logging data,geochemical analysis, fluorescence analysis, and oil testing and production data to address these issues.Following a “stratification and differentiation” approach, the study identified seven distinct hydrocarbon migration and accumulation units(HMAU) in the Pinghu slope area based on the structural morphology characteristics, hydrocarbon source-reservoir-cap rock patterns, hydrocarbon migration pathways, and hydrocarbon supply range. Detailed analysis was conducted to examine the hydrocarbon distribution patterns and controlling factors within each migration and accumulation unit across different structural units, including high, medium, and low structural components. All data sources support a “southern-northern sub-area division, eastern-western sub-belt division, and variations in hydrocarbon accumulation” pattern in the Pinghu slope belt. The degree of hydrocarbon accumulation is controlled by the factors of structural morphology, hydrocarbon generation potential of source rocks, the spatial position of source slopes, fault sealing capacity, and sand body distribution. Furthermore, different coupling patterns of faults and sand bodies play a pivotal role in governing hydrocarbon enrichment systems across various migration and accumulation units. These observations indicate that three hydrocarbon accumulation patterns have been established within the slope belt, including near-source to far-source gentle slope with multiple hydrocarbon kitchens in the XP1-XP4 zones, near-source to middle-source gentle slope with dual-hydrocarbon kitchens in the XP5 zone, and near-source steep slope with a single hydrocarbon kitchen in the XP6-XP7 zones. These findings contribute to enhancing the theoretical system of hydrocarbon accumulation in the slope belt.

采用基因测序鉴定ABO疑难血型12例

目的采用基因测序方法鉴定12例ABO疑难血型。方法 2018年1月—2019年6月收集本院正反定型不符的疑难血型标本12例,采用基因测序方法检测基因型。结果 12例标本基因型分别为2例A201/B01、1例Bx01/O01、1例Bw11/O01、1例A102/Bx14、1例B01/O01、1例A102/O01、1例A102/O02、2例在A101/B01基础上分别发生150G>C、240T>C新突变、1例B01/B01发生431G>T新突变、1例O02/O02其FUT1及FUT2分别发生35C>T及357C>T突变。结论基因测序可以辅助血清学鉴定疑难血型,但仍存在一定的局限性。

Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3K/AKT/MCP-1 axis

Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis.Human-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system diseases.In this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying mechanism.Our results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral hemorrhage.Additionally,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory microenvironment.RNA sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier integrity.Treatment with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these effects.In summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.

Epidemiological and clinical characteristics of COVID-19 patients in Hengyang,Hunan Province,China

BACKGROUND In December 2019,an ongoing outbreak of coronavirus disease 2019(COVID-19)was first identified in Wuhan,China.The characteristics of COVID-19 patients treated in local hospitals in Wuhan are not fully representative of patients outside Wuhan.Therefore,it is highly essential to analyze the epidemiological and clinical characteristics of COVID-19 in areas outside Wuhan or Hubei Province.To date,a limited number of studies have concentrated on the epidemiological and clinical characteristics of COVID-19 patients with different genders,clinical classification,and with or without basic diseases.AIM To study the epidemiological and clinical characteristics of COVID-19 patients in Hengyang(China)and provide a reliable reference for the prevention and control of COVID-19.METHODS From January 16 to March 2,2020,a total of 48 confirmed cases of COVID-19 were reported in Hengyang,and those cases were included in this study.The diagnostic criteria,clinical classification,and discharge standard related to COVID-19 were in line with the Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia(Trial Version 7)released by National Health Commission and National Administration of Traditional Chinese Medicine.The presence of SARS-CoV-2 in pharyngeal swab specimens was detected by quantitative reverse transcription polymerase chain reaction.All the data were imported into the excel worksheet and statistically analyzed by using SPSS 25.0 software.RESULTS A total of 48 cases of COVID-19 were collected,of which 1 was mild,38 were moderate,and 9 were severe.It was unveiled that there were 31(64.6%)male patients and 17(35.4%)female patients,with a female-to-male ratio of 1.82:1.The range of age of patients with COVID-19 was dominantly 30-49 years old[25(52.1%)of 48],followed by those aged over 60 years old[11(22.9%)].Besides,29.2%(14 of 48)of patients had basic diseases,and 57.2%(8 of 14)of patients with basic diseases were aged over 60 years old.The occupations of 48 COVID-19 patients were mainly farmers working in agricultural production[15(31.5%)of 48],rural migrant workers from Hengyang to Wuhan[15(31.5%)],and service workers operating in the service sector[8(16.7%)].The mean latent period was 6.86±3.57 d,and the median was 7[interquartile range(IQR):4-9]d.The mean time from onset of symptoms to the first physician visit was 3.38±2.98(95%CI:2.58-9.18)d,with a median of 2(IQR:1-5)d,and the mean time from hospital admission to confirmed diagnosis was 2.29±2.11(95%CI:1.18-6.42)d,with a median of 2(IQR:1-3)d.The main symptoms were fever[43(89.6%)of 48],cough and expectoration[41(85.4%)],fatigue[22(45.8%)],and chills[22(45.8%)].Other symptoms included poor appetite[13(27.1%)],sore throat[9(18.8%)],dyspnea[9(18.8%)],diarrhea[7(14.6%)],dizziness[5(10.4%)],headache[5(10.4%)],muscle pain[5(10.4%)],nausea and vomiting[4(8.3%)],hemoptysis[4(8.3%)],and runny nose[1(2.1%)].The numbers of peripheral blood leukocytes,lymphocytes,and eosinophils were significantly reduced in the majority of the patients.The levels of C-reactive protein,fibrinogen,blood glucose,lactate dehydrogenase,Ddimer,alanine aminotransferase(ALT),aspartate aminotransferase(AST),gamma-glutamyl transferase(γ-GT),myoglobin(MB),and creatine kinase(CK)were increased in 64.6%,44.7%,43.2%,37.0%,29.5%,22.9%,20.8%,21.6%,13.6%,and 12.8%of patients,respectively.The incidence of ALT elevation in male patients was remarkably higher than that in females(P<0.01),while the incidences of AST,CK,and blood glucose elevations in severe patients were remarkably higher than those in moderate patients(P<0.05,respectively).Except for the mild patients,chest computed tomography showed characteristic pulmonary lesions.All the patients received antiviral drugs,38(79.2%)accepted traditional Chinese medicine,and 2(4.2%)received treatment of human umbilical-cord mesenchymal stem cells.On March 2,2020,48 patients with COVID-19 were all cured and discharged.CONCLUSION Based on our results,patients with COVID-19 often have multiple organ dysfunction or damage.The incidences of ALT elevation in males,and AST,CK,and blood glucose elevations in severe patients are remarkably higher.

Quantum interference of multi-orbital effects in high-harmonic spectra from aligned carbon dioxide and nitrous oxide

We investigate experimentally multi-orbital effects in high-order harmonic generation(HHG) from aligned CO2 and N2O molecules by intense femtosecond laser fields with linear and elliptical polarizations.For either of the aligned molecules, a minimum in the harmonic spectrum is observed, the position of which shifts to lower-order harmonics when decreasing the intensity or increasing the ellipticity of the driving laser.This indicates that the minimum originates from the dynamic interference of different channels, of which the tunneling ionization and recombination are contributed via different molecular orbitals.The results show that both the highest occupied molecular orbital(HOMO) and low-lying HOMO-2 in CO2(or HOMO-1 in N2O) contribute to the molecular HHG in both linearly and elliptically polarized strong laser fields.Our study would pave a way for understanding multi-electron dynamics from polyatomic molecules irradiated by strong laser fields.

Development and Validation of an Automatic Ultrawide-Field Fundus Imaging Enhancement System for Facilitating Clinical Diagnosis:A Cross-Sectional Multicenter Study

In ophthalmology,the quality of fundus images is critical for accurate diagnosis,both in clinical practice and in artificial intelligence(AI)-assisted diagnostics.Despite the broad view provided by ultrawide-field(UWF)imaging,pseudocolor images may conceal critical lesions necessary for precise diagnosis.To address this,we introduce UWF-Net,a sophisticated image enhancement algorithm that takes disease characteristics into consideration.Using the Fudan University ultra-wide-field image(FDUWI)dataset,which includes 11294 Optos pseudocolor and 2415 Zeiss true-color UWF images,each of which is rigorously annotated,UWF-Net combines global style modeling with feature-level lesion enhancement.Pathological consistency loss is also applied to maintain fundus feature integrity,significantly improving image quality.Quantitative and qualitative evaluations demonstrated that UWF-Net outperforms existing methods such as contrast limited adaptive histogram equalization(CLAHE)and structure and illumination constrained generative adversarial network(StillGAN),delivering superior retinal image quality,higher quality scores,and preserved feature details after enhancement.In disease classification tasks,images enhanced by UWF-Net showed notable improvements when processed with existing classification systems over those enhanced by StillGAN,demonstrating a 4.62%increase in sensitivity(SEN)and a 3.97%increase in accuracy(ACC).In a multicenter clinical setting,UWF-Net-enhanced images were preferred by ophthalmologic technicians and doctors,and yielded a significant reduction in diagnostic time((13.17±8.40)s for UWF-Net enhanced images vs(19.54±12.40)s for original images)and an increase in diagnostic accuracy(87.71%for UWF-Net enhanced images vs 80.40%for original images).Our research verifies that UWF-Net markedly improves the quality of UWF imaging,facilitating better clinical outcomes and more reliable AI-assisted disease classification.The clinical integration of UWF-Net holds great promise for enhancing diagnostic processes and patient care in ophthalmology.

Modeling and analysis of gradient metamaterials for broad fusion bandgaps

A gradient metamaterial with varying-stiffness local resonators is proposed to open the multiple bandgaps and further form a broad fusion bandgap.First,three local resonators with linearly increasing stiffness are periodically attached to the spring-mass chain to construct the gradient metamaterial.The dispersion relation is then derived based on Bloch's theorem to reveal the fusion bandgap theoretically.The dynamic characteristic of the finite spring-mass chain is investigated to validate the fusion of multiple bandgaps.Finally,the effects of the design parameters on multiple bandgaps are discussed.The results show that the metamaterial with a non-uniform stiffness gradient pattern is capable of opening a broad fusion bandgap and effectively attenuating the longitudinal waves within a broad frequency region.

Generating attosecond pulses with controllable polarization from cyclic H_(3)^(2+) molecules by bichromatic circular fields

We investigate the polarization properties of harmonics from the cyclic H_(3)^(2+) molecular ions in tailored bichromatic counter-rotating circularly polarized(BCCP)fields by solving the time-dependent Schrödinger equation.The allowed harmonics and their helicities are associated with the symmetry compatibility of the field-target systems,and large intensity difference between adjacent harmonics with opposite helicities appears in a wide spectral range when the BCCP field is at certain rotation angles.We try to explain the intensity difference by using a recombination model based on the quantum-orbit theory and by analyzing the ionization pathways.Moreover,to synthesize attosecond pulse trains with tunable polarization,the intensity difference is manipulated by introducing a seed XUV field,and by changing the relative amplitude ratio as well as the helicity of BCCP fields.

中国与“一带一路”沿线国家跨国科学研究合作何以可能?——一项定性比较分析

【问题】中国与“一带一路”沿线国家之间的跨国科学研究合作是承载“一带一路”建设科技交流与创新发展使命的重要议题,然而由于许多“一带一路”沿线国家的制度和法律环境尚不健全,甚至部分国家还存在较强的政治风险和文化冲突,这种合作并非易事。在此背景下,中国与“一带一路”沿线国家之间的跨国科学研究合作何以成为可能?【方法】本研究从宏观分析视角提出了中国与“一带一路”沿线国家之间跨国科学研究合作影响因素的分析框架,并采用模糊集定性比较分析方法识别了36个沿线国家案例中的跨国科学研究合作影响因素及其条件组合。【发现】资源投入与制度环境是影响跨国科学研究合作的重要因素,两者相互耦合共同构成跨国科学研究合作的实现路径。进一步地,本研究依据资源投入与制度环境不同耦合程度,识别出强强联合型、资源主导型、经贸带动型与政治兜底型四种跨国科学研究合作类型。【贡献】论文提出的分析框架弥补了以往研究聚焦于中观和微观层面跨国科学研究合作影响因素分析的局限性,区分了不同伙伴国家与中国开展跨国科学研究合作的各种途径,可以更为准确地解释全球治理背景下的跨国科学研究合作机制,对于中国进一步深入推进与沿线国家之间的跨国科学研究合作、提升合作效果具有积极意义。

中国全球气候治理观的要义、基础与实践

全球气候治理观是指治理主体对全球气候治理体系价值目标的基本看法和主张。中国在参与全球气候治理的长期实践中,已经形成了系统的全球气候治理观,它以合作共赢、公平合理为核心要义,具有鲜明的中国特色。中国全球气候治理观建立在三个基础之上,即中国传统文化中关于社会正义的思想、中国国际关系理论、新型国际关系与人类命运共同体的理念。中国在参与全球气候治理的实践中,积极践行其全球气候治理观,既有力推动了国内气候治理的进程,也对全球气候治理机制的发展发挥了重要作用。

静脉留置针多点采血在糖耐量试验中的临床应用效果

目的探讨静脉留置针多点采血在糖耐量试验中的临床应用效果。方法选取2019年2~10月于我院进行糖耐量试验的80例患者作为研究对象,应用盲选分组法将其分为对照组和观察组,每组各40例。对照组患者采用常规静脉穿刺方法进行采血操作,观察组患者应用静脉留置针进行多点采血操作。比较两组患者对应采血标本各时间点的血糖水平、收缩压、精神压力和病情严重程度。结果两组患者空腹及服用葡萄糖后30 min、1、2及3 h的血糖水平比较,差异无统计学意义(P>0.05)。采血后,观察组患者各时间点的收缩压均低于对照组,差异有统计学意义(P<0.05)。采血后,观察组患者的精神压力和病情程度评分均低于对照组,差异有统计学意义(P<0.05)。结论糖耐量试验患者采用静脉留置针多点采血方法进行采血处理,可有效避免对其心理状态及血压产生较大影响,并可得到与常规采血方法相似的血糖检测结果,值得进行推广应用。

全球气候治理中的中美欧三边关系:新变化与连续性

特朗普执政初期美国气候政策的倒退、尤其是美国宣布退出《巴黎协定》,给全球气候治理带来了新的不确定性,也为该领域中美欧三边关系的发展增添了变数。这包括:中美欧针对《巴黎协定》的整体合作性下降,竞争性增强;特朗普的决定也加剧了全球气候治理中的领导力赤字问题,使得三方集体领导的模式短期内难以为继。此外,经济方面的分歧则干预了后巴黎时代的中国和欧盟在全球气候治理领域的合作逻辑。同时,次国家行为体在三边关系中的地位和作用提升,使中美欧气候变化三边关系的层次和维度更为多元。与此同时,气候变化仍将是中美欧三方互动的重要问题领域;三方仍会维持多边层次形式上的"三方共处"模式;这种三边关系仍将维持其开放性。同样重要的是,中国与欧美在清洁能源和碳交易机制方面保持了务实合作。这些都表明了中美欧在全球气候治理中三边关系的连续性和延展性。

35 kV线路避雷器与避雷线防雷效果量化比较分析

通过建立35 kV线路的仿真模型,研究线路在有避雷线无避雷器、无避雷线有避雷器以及有避雷线和避雷器这3种情况下,线路耐雷水平的差异以及杆塔分流系数的变化情况。仿真结果表明:在同样的接地电阻下,杆塔在有避雷线无避雷器时的分流系数要比有避雷线和避雷器时的分流系数至少大20%。另当接地电阻小于20Ω时,线路在无避雷线有避雷器的情况下,其耐雷水平是有避雷线无避雷器情况下的1.8~2.0倍;而线路在有避雷线和避雷器的情况下的耐雷水平是有避雷线无避雷器情况下的1.9~2.3倍。当接地电阻分别为20、15、10、5Ω时,线路在有避雷线无避雷器的情况下的耐雷水平的提高效果不到其他2种情况的60%。研究结果对于35 kV线路的防雷保护具有一定的指导作用和参考价值。

脂肪干细胞对膝骨关节炎疼痛及软骨修复的影响

目的观察脂肪干细胞(ADSCs)对膝骨关节炎(KOA)大鼠关节疼痛和软骨修复的作用。方法从大鼠腹股沟抽取脂肪制备培养ADSCs,以碘乙酸法复制大鼠KOA疼痛模型。将40只SD大鼠随机分为空白组、KOA模型组、ADSCs低浓度治疗组、ADSCs中浓度治疗组、ADSCs高浓度治疗组,每组8只。采用低(1×10^6个/ml)、中(1×10^7个/ml)、高(1×10^8个/ml)3种浓度的ADSCs对大鼠进行双侧关节腔注射干预,每周注射1次,定期观察大鼠的生理行为并评价疼痛指标,注射4次后取大鼠膝关节进行组织病理学观察及Mankin's评分。结果压痛实验结果表明,模型复制后第2和4周时,5组大鼠的压痛阈值比较结果:①不同时间点大鼠压痛阈值有差异(P<0.05);②5组间大鼠压痛阈值无差异(P>0.05);③5组间的压痛阈值变化趋势有差异(P<0.05)。热痛实验结果表明,模型复制后第2和4周时,5组大鼠的热痛阈值比较结果:①不同时间点大鼠热痛阈值有差异(P<0.05);②5组间大鼠热痛阈值无差异(P>0.05);③5组的热痛阈值变化趋势无差异(P>0.05)。病理学结果表明,与空白组比较,KOA模型组大鼠膝关节软骨表面缺损,缺损处软骨细胞丢失,蛋白聚糖降解,软骨下骨呈现纤维化退变;低、中、高浓度ADSCs对大鼠膝关节均有改善作用。其中ADSCs低浓度治疗组仍可见软骨表面缺损、软骨细胞缺失和肥大化表型;ADSCs中浓度治疗组软骨细胞存活,但仍有表面缺损和细胞肥大化退变;ADSCs高浓度治疗组软骨基本恢复正常,软骨面增厚,仅有少量肥大软骨细胞。KOA模型组的Mankin's评分均高于空白组、ADSCs低浓度治疗组、ADSCs中浓度治疗组和ADSCs高浓度治疗组(P<0.05)。结论ADSCs可改善KOA大鼠关节疼痛,并修复软骨损伤。该技术可用于临床KOA的辅助治疗。

黄河干流生态流量赤字及其成因

为准确核算和评估黄河生态流量,以黄河干流吉迈、唐乃亥、贵德、兰州、石嘴山、龙门、花园口和利津为研究对象,运用6种水文学方法分析生态流量过程,评估1956-2013年各断面生态流量赤字及其成因。研究表明:生态流量核算对方法选择较为敏感,其中Q90_Q50法的计算结果远高于其他5种方法;黄河干流8个断面的生态流量为(47±9)、(273±59)、(273±53)、(456±103)、(433±94)、(473±124)、(639±172)和(727±160)m^3/s,占天然径流量的36%~43%,其中5-11月占全年生态流量的70%~77%;在过去近60年,1985-2003年是黄河干流存在生态流量赤字最为严重的时期,吉迈、唐乃亥、贵德和兰州断面的生态流量赤字主要发生在枯水期,而石嘴山、龙门和花园口断面主要发生在丰水期,利津断面集中在上半年;人类耗水是造成生态流量赤字的最重要的原因,其次为气候变化。未来要加强用不同方法全面评估黄河干流、支流的生态流量,推动"精准"节水,完善水量调度方案,最大程度地减少生态流量赤字风险。

肠道菌群与脓毒症相互关系的研究进展

脓毒症的发生发展与肠道菌群失调密切相关.肠道菌群失调可以通过肠黏膜屏障功能破坏、黏膜免疫功能破坏和细菌移位等环节诱导脓毒症的发生.同时脓毒症也可以加重肠道菌群失调,加重肠黏膜屏障功能破坏,导致机体多器官功能障碍.本文通过探讨肠道菌群和脓毒症之间的相互关系,为脓毒症临床干预提供思路.

高校语文教学“课程思政”有效策略研究

在提倡“课程思政”理念的大背景下,高校语文作为高等学校的公共性教育课程,兼具基础性、覆盖性、工具性、人文性、审美性等特点。其教学内容隐含着丰富的思政教育资源,与高校思政理论课的根本任务一致,在实施“课程思政”方面占据着独特优势。因此,高校要进一步完善思政管理制度,加强课程建设,带领语文教师群体充分挖掘语文课程中的思政元素,帮助其不断提高思政意识和思政能力,有效推进“课程思政”与“思政课程”同向并行,形成协同效应。

Li-Cu合金作为锂电池负极材料的电化学性能

从含有LiTFSI和Cu(p-oTs)2的1-乙基-3-甲基咪唑双三氟甲磺酰亚胺盐和N-甲基吡咯烷酮混合体系中电沉积出了Li-Cu合金。循环伏安测试表明,当Li从Li-Cu合金上溶解后,留下的Cu骨架仍然可以保持稳定。Li-Cu/LiFePO4电池的充放电测试表明当以0.2C的倍率充放电20个循环以后,电池的比容量可稳定保持在138.96 mAh/g。电化学阻抗谱和塔菲尔曲线测试表明在经过四个充放电循环后或者在电解液中浸泡三天以后,在Li-Cu合金表面形成了稳定的SEI膜。

Practical constrained least-square algorithm for moving source location using TDOA and FDOA measurements

By utilizing the time difference of arrival （TDOA） and frequency difference of arrival （FDOA） measurements of signals received at a number of receivers, a constrained least-square （CLS） algorithm for estimating the position and velocity of a moving source is proposed. By utilizing the Lagrange multipliers technique, the known relation between the intermediate variables and the source location coordinates could be exploited to constrain the solution. And without requiring apriori knowledge of TDOA and FDOA measurement noises, the proposed algorithm can satisfy the demand of practical applications. Additionally, on basis of con- volute and polynomial rooting operations, the Lagrange multipliers can be obtained efficiently and robustly allowing real-time imple- mentation and global convergence. Simulation results show that the proposed estimator achieves remarkably better performance than the two-step weighted least square （WLS） approach especially for higher measurement noise level.

Comparative study on artificial intelligence systems for detecting early esophageal squamous cell carcinoma between narrow-band and white-light imaging

BACKGROUND Non-magnifying endoscopy with narrow-band imaging(NM-NBI)has been frequently used in routine screening of esophagus squamous cell carcinoma(ESCC).The performance of NBI for screening of early ESCC is,however,significantly affected by operator experience.Artificial intelligence may be a unique approach to compensate for the lack of operator experience.AIM To construct a computer-aided detection(CAD)system for application in NMNBI to identify early ESCC and to compare it with our previously reported CAD system with endoscopic white-light imaging(WLI).METHODS A total of 2167 abnormal NM-NBI images of early ESCC and 2568 normal images were collected from three institutions(Zhongshan Hospital of Fudan University,Xuhui Hospital,and Kiang Wu Hospital)as the training dataset,and 316 pairs of images,each pair including images obtained by WLI and NBI(same part),were collected for validation.Twenty endoscopists participated in this study to review the validation images with or without the assistance of the CAD systems.The diagnostic results of the two CAD systems and improvement in diagnostic efficacy of endoscopists were compared in terms of sensitivity,specificity,accuracy,positive predictive value,and negative predictive value.RESULTS The area under receiver operating characteristic curve for CAD-NBI was 0.9761.For the validation dataset,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of CAD-NBI were 91.0%,96.7%,94.3%,95.3%,and 93.6%,respectively,while those of CAD-WLI were 98.5%,83.1%,89.5%,80.8%,and 98.7%,respectively.CAD-NBI showed superior accuracy and specificity than CAD-WLI(P=0.028 and P≤0.001,respectively),while CAD-WLI had higher sensitivity than CAD-NBI(P=0.006).By using both CAD-WLI and CAD-NBI,the endoscopists could improve their diagnostic efficacy to the highest level,with accuracy,sensitivity,and specificity of 94.9%,92.4%,and 96.7%,respectively.CONCLUSION The CAD-NBI system for screening early ESCC has higher accuracy and specificity than CAD-WLI.Endoscopists can achieve the best diagnostic efficacy using both CAD-WLI and CAD-NBI.