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病理是疾病诊断的“金标准”，人工智能正逐渐运用到病理专业，引起病理学的巨大变革。计算病理是数字病理和人工智能技术的组合，它利用高性能计算设备对人类知识和经验进行量化建模，辅助病理医师实现更精准、更客观、可重复的诊断。此外，计算病理技术还将辅助医师超越诊断任务，实现疗效预测和预后等更复杂问题的解决，从而进一步推动精准医学的发展。本文讨论计算病理在细胞、组织、切片层次的图像计算，以及基于领域知识启发的组织形态学描述，并讨论它们在实现疾病的辅助检测、诊断、预测和预后等目标及任务的研究进展，最后对计算病理领域存在的挑战以及未来的发展方向作出展望。.

This study aims to evaluate the changes in left ventricular diastolic function after coronary artery bypass grafting through tissue Doppler imaging (TDI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration and the correlation between the two.A total of 133 patients who underwent coronary artery bypass grafting between January 2016 and December 2018 were included in this study. Echocardiography and NT-proBNP concentration were reviewed pre-operation, 1 month post-operation, and 3-6 months post-operation. The transmitral peak flow velocity (E) of the mitral valve was measured at each of the three-time points using spectral Doppler imaging. The mitral annulus displacement (Ea peak and Aa peak) was then measured at each of the time points using TDI, and the E/Ea ratio was calculated. Subsequently, the correlation of the E value, Ea value, and E/Ea ratio with NT-proBNP concentration was statistically analyzed.The data obtained at the three-time points were compared with the respective concentrations of NT-proBNP. Multiple linear regression analysis revealed a correlation between NT-proBNP concentration and E value, Ea value, and E/Ea ratio.Left ventricular diastolic function gradually recovered at 1 month and 3-6 months after coronary artery bypass grafting. There was a correlation between TDI-related values and NT-proBNP concentration.

Aims To investigate the incidence of and factors associated with anastomotic leakage (AL) following gastrectomy for gastric cancer. Methods We retrospectively analyzed 3632 patients who underwent a laparoscopic gastrectomy or open gastrectomy for gastric cancer. A logistic regression model was used to identify the determinant variables, and a nomogram for AL was developed. Results A total of 3632 patients were included in the study, 50 of whom (1.4%) developed AL. Postoperative deaths occurred in 6 (0.2%) patients with AL failure to rescue. Esophagojejunal AL (27/50) and Billroth I AL (20/50) were the most common types of AL. Gastrografin swallow was the main diagnostic method. The diagnosis was made a median of 9 days postoperatively. The median healing time for AL was 34.5 days. Of the 50 AL patients, 56% of patients could be managed nonsurgically, whereas 28% of patients required percutaneous radiologic drainage, 6% of patients were treated by endoscopy, and 10% of patients required a second surgery. A multivariate analysis showed the following adverse risk factors for AL: age ≥65 years, hemoglobin ≤8.0 g/dL and malnourishment. A multivariable model for AL showed a strong optimism-adjusted discrimination (concordance index, 0.675). The 5-year overall survival rates for patients without or with AL were 59.4% and 67.4%, respectively (p = 0.354). Conclusions AL was infrequent but was more prevalent in patients with age ≥65 years, hemoglobin ≤8.0 g/dL and malnourishment. We created a novel nomogram that can provide individualized prediction of AL in patients after a gastrectomy for gastric cancer, which may help clinicians in making treatment decisions.

The radial velocity (RV) is a basic physical quantity which can be determined through Doppler shift of the spectrum of a star. The precision of RV measurement depends on the resolution of the spectrum we used and the accuracy of wavelength calibration. In this work, radial velocities of LAMOST-II medium resolution (R ~ 7500) spectra are measured for 1,594,956 spectra (each spectrum has two wavebands) through matching with templates. A set of RV standard stars are used to recalibrate the zero point of the measurement, and some reference sets with RVs derived from medium/high-resolution observations are used to evaluate the accuracy of the measurement. Comparing with reference sets, the accuracy of our measurement can get 0.0227 km s/1 with respect to radial velocities standard stars. The intrinsic precision is estimated with the multiple observations of single stars, which can achieve to 1.36 km s/1,1.08 km s/1, 0.91 km s/1 for the spectra at signal-to-noise levels of 10, 20, 50, respectively., published by ApJs. 13 pages, 13 figures

Research on the clinicopathology and prognosis of gastric neuroendocrine carcinoma (GNEC) is rare, and a uniform standard for treatment has not been established. Therefore, we retrospectively analyzed the clinical data of 132 cases of GNEC to investigate the factors influencing prognosis.A total of 132 patients diagnosed with GNEC at Fujian Medical University Union Hospital from January 2006 to December 2013 were enrolled. This study was performed to analyze the factors related to patient prognosis.In total, 58 men and 74 women whose ages ranged from 38 to 83 years old (62 ± 10) were enrolled. The 1- and 3-year survival rates for these patients were 83.9% and 47.6%, respectively. Of these patients, 100 underwent radical resection, 22 underwent palliative resection, and 10 received chemotherapy alone. The median survival times following radical resection, palliative resection and chemotherapy alone were 48, 20 and 12 months, respectively (P 0.01). Univariate and multivariate survival analyses of patients who underwent radical resection showed that tumor size, N stage, Ki-67 labeling index, mitotic index and the application of postoperative adjuvant chemotherapy were independent factors affecting patient prognosis. The correlation analysis of the Ki-67 labeling index and mitotic index with prognosis showed that patient survival decreased significantly when the Ki-67 labeling index increased (P 0.05).Patients who underwent radical resection had the best prognosis among GNEC. For these patients, tumor size, N stage, Ki-67 labeling index, mitotic index and the application of postoperative adjuvant chemotherapy were the clinicopathological factors significantly associated with patient prognosis.

The formation behavior of coated explosive formed projectiles (CEFP) with different structure and material liners were numerically simulated by AUTODYN-2D. There are many factors affecting the coating effect of CEFP, the numerical simulation results show that the structure and liner material have remarkable influence on the velocity and forming effect of the CEFP. For the coating effect, the liner thickness has an optimum range. When the liner thickness is small or large, the explosive balls will deform seriously or not be wrapped sufficiently, and the EFP velocity decreases with increasing the axial thickness of the liner, when the liner thickness is 4.5mm and 5mm, the coating effect is the best. The curvature of liner also has an optimum interval, when the curvature of liner is small or large, the explosive balls will be lengthened or retrogradely compressed and destroyed, and the EFP velocity increases with the decreasing the curvature of the liner. When aluminum, iron, copper and tungsten are used as liner materials, the density and ductility of the material will affect the coating effect. The high density copper liner can achieve a good coating effect and well penetration performance.

The jet formation and penetration capability of hypervelocity double-layer liner shaped charges (HDLLSCs) against rolled homogeneous armor (RHA) targets are investigated by numerical simulation. The HDLLSCs with different cone angle and relative position of disc are simulated to investigate the influence of these parameters on penetration capability and compare with a traditional conical shaped charge (CSC). The simulation results show that, the tip velocity of the jet formed by HDLLSCs with a tantalum disc is lager by 6.8% compared with that formed by the CSCs. The three stages of jet formation for HDLLSC including converge, formation, and secondary impact are revealed and discussed. The penetration capability of HDLLSCs is influenced by the coupled effect of cone angle and relative position of disc, a larger relative position of disc is more suitable for a large cone angle. In addition, the standoff also has a significant effect on the penetration depth of HDLLSCs, the penetration depth increases from 3.31 charge diameter (CD) to 6.52 CD with the standoff increasing from 1.5 CD to 4.0 CD. Moreover, the penetration depth of the jet formed by HDLLSCs is larger by 18.5% compared with that formed by the CSCs at the standoff of 4.0 CD.

Issues resulting from failure of steam-side oxide scales in boiler superheater or reheater tubes seriously influence the safety of coal-fired power plants. In this work, an analysis model for the failure of steam-side oxide scales during unsteady thermal processes is established. This model employs the advanced oxide scale failure diagram as the failure criterion, and also takes into account the influence of temperature on the coefficients of thermal expansion of both metal substrate and oxide scale. Since the stochastic nature of related geometrical, mechanical, and thermophysical parameters may hinder the usual deterministic investigation from obtaining a reliable evaluation, probabilistic failure evaluation which is not based on bivalent logic is thus performed. Focusing on the unsteady thermal processes induced by the variation of steam temperature, effects of oxide scale thickness as well as different steam temperature variation processes on the failure probability of steam-side oxide scales are analyzed. It is found that the failure probability of thicker steam-side oxide scales is higher, while through reasonably selecting steam temperature variation mode and appropriately lengthening variation duration, lower failure probability can be achieved. Feasible measures are presented with the aspiration to solve the steam-side oxide scale failure issues.

To explore the therapeutic potential of transplantation of adipose derived mesenchymal stem cells (ADMSCs) in rats osteoarthritis caused by anterior cruciate ligament transection.Rats peritoneal adipose tissues were used to extract ADMSCs.Cell morphological appearance was documented and flow cytometric cell cycle was used to identify ADMSCs. Anterior cruciate ligament transection was used to induce knee osteoarthritis in rats. ADMSCs were injected into the knee cavities. Knee joint pathology was performed to observe the treatment effects. QRT-PCR and Western blot were used to identify the targets of ADMSCs.ADMSCs were successfully extracted, separated, cultured and identified. Two and eight weeks after ADMSCs transplantation, pathology showed significantly attenuation of arthritis including osteophyte and synovitis, reflecting in significantly improvement of both osteophyte and synovitis grading compared to the controls. QRT-PCR and Western blot revealed that collagen Ⅱ expression was significantly up-regulated after ADMSCs transplantation compared to the controls.MMP-13, but not other MMP-1, MMP-3 or MMP-9 was reduced when ADMSCs were co-cultured with primary chondrocytes. DDR-2 expression in chondrocyte was heavily up-regulated when stimulated by TNF-α in vitro. However, ADMSCs could reverse the effect when co-cultured with chondrocyte, implying that ADMSCs may suppress the expression of DDR-2. IL-1β suppressed the cartilage differentiation of ADMSCs, and Actinomycin D (DDR-2 inhibitor) could reverse the effect.ADMSCs can attenuate osteoarthritis induced by anterior cruciate ligament transection in rats by suppressing the expression of MMP-13, and the upstream target spot may be DDR-2.

Modern radars use complex waveforms to obtain high detection performance and low probabilities of interception and identification. Signals intercepted from multiple radars overlap considerably in both the time and frequency domains and are difficult to separate with primary time parameters. Time–frequency analysis (TFA), as a key signal-processing tool, can provide better insight into the signal than conventional methods. In particular, among the various types of TFA, parameterized time-frequency analysis (PTFA) has shown great potential to investigate the time–frequency features of such non-stationary signals. In this paper, we propose a procedure for PTFA to separate overlapped radar signals; it includes five steps: initiation, parameterized time-frequency analysis, demodulating the signal of interest, adaptive filtering and recovering the signal. The effectiveness of the method was verified with simulated data and an intercepted radar signal received in a microwave laboratory. The results show that the proposed method has good performance and has potential in electronic reconnaissance applications, such as electronic intelligence, electronic warfare support measures, and radar warning.

Aim To determine the features of caesarean scar ectopic pregnancy (CSP) by using magnetic resonance imaging (MRI) in the first trimester. Materials and methods Thirty-nine women with CSP in the first trimester were initially selected and underwent transvaginal ultrasound and MRI examinations. Thirty-five patients with CSP were finally included in this study. Results The CSPs were categorized into three groups: type I, in which a thin-walled diverticulum is present at the caesarean section scar (CSS) defect and the gestational sac (GS) is embedded in the diverticulum; type II, in which a thin-walled diverticulum is present at the CSS defect and the GS is partially embedded in the diverticulum; type III, in which a niche is present in the CSS defect and the GS is mainly embedded in the isthmus. Types I, II, and III CSP occurred in 40, 46, and 14% of the women, respectively. There was no significant difference between the three types in the minimum thickness of the CSS defect. In types I and II, there was a positive correlation in the maximum inlet diameter of the CSS defect and the approximate area of the GS. Conclusion Using MRI, most CSPs present as a diverticulum at the CSS defect, and the CSS defect becomes weaker with the growth of the GS. MRI showed detailed features of the CSP.

The aim of this study is to evaluate the long-term effect of negative lymph node (LN) counts on the prognosis after curative distal gastrectomy among gastric cancer patients.The study enrolled 634 patients with gastric cancer, who had undergone curative resection (R0) with distal gastrectomy from 1995 to 2004. Long-term surgical outcomes and relationships between the negative LN count and the 5-year survival rate were investigated.The 5-year survival rate of the entire cohort was 57.6%. The number of metastasis negative LN was positively associated with the retrieved node according to the Pearson's correlation test (P 0.001). Cox regression analysis showed the negative LN count was an independent predictor of survival (P 0.05). Based on the statistical assumption the best fitting linear, linear regression showed a significant survival improvement based on increasing negative LN count for patients with stages I (P = 0.014), II (P = 0.011) and III (P = 0.003). The greatest survival differences were observed at cutoff value 10 negative LN counts for stage I, and 15 for stages II, III and IV.Negative LN counts can reflect the extent of lymphadenectomy for gastric cancer after curative distal gastrectomy. The higher the negative LN count, the better the survival would be; the best long-term survival outcome was observed on the negative LN count more than 10 (stage I) or 15 (stages II, III, and IV).

The permeability of CO2 through polyurethane was investigated. It is found that the permeability increases with the decrease of hard segment content and the increase of soft segment length; however, no change of activation energy is involved. The permeability increases with the elevation of annealing temperature. The temperature dependence of permeability observes the Arrhenius equation at temperatures below 60–80°C, but it deviates at temperatures above this range. This deviation would be attributed to the increase of mixing of hard and soft segments as a result of the dissociation of short-range order in hard segment domains.

An HPLC method was developed with normal HPLC-chiral complex mobile phase for the separation and determination of D- and L-thyroxine enantiomers (D- and L-T4) in human plasma. The method includes extraction of thyroxine from plasma and separation of thyroxine enantiomers on HPLC silica column with chiral eluent containing L-proline, cupric acetate and triethylamine (TEA). The sensitivity of the method was 0.1 mg/L. The precisions of inter-day and intra-day, linearity, extraction recovery, and stability of T4 enantiomers in plasma and in deproteinized plasma were determined for the validation of the method. Baseline enantioseparation of the compounds containing D- and L-T4 was achieved. Meantime we determined the concentrations of D-T4 and L-T4 in plasma of 15 volunteers with euthyroid, hypothyroid and hyperthyroid symptoms. Liquid chromatographic method based on the described procedure was useful for the determination of D- and L-thyroxine in patient plasma and for pharmacokinetics investigation.