Microvascular structural changes in esophageal squamous cell carcinoma pathology according to intrapapillary capillary loop types under magnifying endoscopy

BACKGROUND The intrapapillary capillary loop(IPCL)characteristics,visualized using magnifying endoscopy,are commonly assessed for preoperative evaluation of the infiltration depth of esophageal squamous cell carcinoma(ESCC).Japan Esophageal Society(JES)classification is the most widely used classification.Microvascular structural changes are evaluated by magnifying endoscopy for the presence or absence of each morphological factor:tortuosity,dilatation,irregular caliber,and different shapes.However,the pathological characteristics of IPCLs have not been thoroughly investigated,especially the microvascular structures corresponding to the deepest parts of the lesions'infiltration.AIM To investigate differences in pathological microvascular structures of ESCC,which correspond to the deepest parts of the lesions'infiltration.METHODS Patients with ESCC and precancerous lesions diagnosed at Peking University Third Hospital were enrolled between January 2019 and April 2023.Patients first underwent magnified endoscopic examination,followed by endoscopic submucosal dissection or surgical treatment.Pathological images were scanned using a threedimensional slice scanner,and the pathological structural differences in different types,according to the JES classification,were analyzed using nonparametric tests and t-tests.RESULTS The 35 lesions were divided into four groups according to the JES classification:A,B1,B2,and B3.Statistical analyses revealed significant differences(aP<0.05)in the short and long calibers,area,location,and density between types A and B.Notably,there were no significant differences in these parameters between types B1 and B2 and between types B2 and B3(P>0.05).However,significant differences in the short calibers,long calibers,and area of IPCL were observed between types B1 and B3(aP<0.05);no significant differences were found in the density or location(P>0.05).CONCLUSION Pathological structures of IPCLs in the deepest infiltrating regions differ among various IPCL types classified by the JES classification under magnifying endoscopy,especially between the types A and B.

Theoretical Analysis of the Pressure OscillationPhenomena in Capillary Pumped Loop

Based on the physical model of capillary pumped loop (CPL) system, the phenomena of pressure oscillation are simplilied and analyzed. From a set of non-linear differential equations, the influence ofsystem parameters on the performance of the CPL is discussed, including the working temperature(the Set point), loop resistance, vapor volume etc. From the analysis, some measures were taken tohoprove the performance of the loop. Meanwhile, the reason why the deprive of the CPL occurs duringthe operation is given by analyzing the theoretical calculation results.

The Effect of Disturbance in the Evaporator on thePerformance of Capillary romped Loop (CPL)

The disturbance, caused by the boiling Phenomena in the inverted meniscus ac evaporator, is of great importancein the normal operation of the CPL, especially When the heat load is low. By theoretical and experimental studies onthis issue, it shows that the evaporator of the CPL operates in a mode of boiling in the Wick. By solving a set ofmomentum equations, it concludes that, this kind of boiling Phenomena in the wick cause no notable negativeinfluence on the normal peiformance of the CPL, although there really edests some adVerse influence during theCPL start-up. Addihonally, the causes of the dry-out of the evaporator under low heat load are conducted in thepaper. The conclusions are verified by subsequent experiments. More details about the experiments are alsodescribed in the paper.

Heat Transfer with Flow and Phase Change in an Evaporator of Miniature Flat Plate Capillary Pumped Loop

An overall two-dimensional numerical model of the miniature flat plate capillary pumped loop （CPL） evaporator is developed to describe the liquid and vapor flow, heat transfer and phase change in the porous wick structure, liquid flow and heat transfer in the compensation cavity and heat transfer in the vapor grooves and metallic wall. The entire evaporator is solved with SIMPLE algorithm as a conjugate problem. The effect of heat conduction of metallic side wall on the performance of miniature flat plate CPL evaporator is analyzed, and side wall effect heat transfer limit is introduced to estimate the performance of evaporator. The shape and location of vapor-liquid interface inside the wick are calculated and the influences of applied heat flux, liquid subcooling, wick material and metallic wall material on the evaporator performance are investigated in detail. The numerical results obtained are useful for the miniature flat plate evaporator performance optimization and design of CPL.

Experimental Studies on Heat Transfer Characteristics in Inverted Evaporator of Micro／Miniature Capillary Pumped Loop

This paper presents the experimental investigation on the heat transfer chaxacteristics in inverted evaporator of Micro/Miniature Capillary Pumped Loop (MCPL). The evaporation heat transfer coefficients as a function of the heat flux density, the geometrical sizes of capillary wick structure and the vapor grooves are shown. Qualitative analysis of the heat transfer characteristics of the inverted evaporator of MCPL is also made.