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Silica aerogels are widely used in many fields for thermal insulation, such as building insulation, electric power energy, energy storage systems, and high-temperature thermal protection due to their excellent insulation performance. Therefore, the heat transfer in silica aerogels and its modeling in recent years have attracted much attention and many valuable achievements have been acquired. The heat transfer in nano-porous silica aerogels and its modeling methods are reviewed in this work. This review starts with a brief introduction of heat transfer characteristics in silica aerogels, including the multi-component and multi-mode coupling effect, size effect, and multiscale effect. Then the heat transfer mechanism of each mode, including heat transfer via gas phase, solid phase, and thermal radiation, is reviewed, and the models for predicting the gaseous thermal conductivity in nanoscale pores, gas-contributed thermal conductivity, the apparent thermal conductivity of solid skeleton, and finally the effective thermal conductivity are collected and discussed in details. Besides, modeling of transient heat transfer in silica aerogels is also briefly introduced. Finally, the conclusions and some problems which need to be further investigated in the future are provided.

Charring composites can provide the most efficient thermal protection shield for the thermal protection system (TPS), which is essential for hypersonic reentry vehicles. It is of great importance to clarify the implication of different porosity configurations of charring composite on the bondline temperature. In the present study, a one-dimensional transient thermal model considering the pyrolysis without the surface recession is built and validated. Based on this model, the thermal protection performance of various porosity distribution design schemes is analyzed when keeping the total pore volume unchanged. The present results show that the scheme with the linear increasing porosity from the bondline to the heated surface can decrease the bondline temperature by 7.8 K and 15.8 K compared with the homogeneous scheme and the linear decreasing scheme, respectively. Further, a scheme with parabolic increasing distribution of porosity are evaluated. It is found that it can reduce the bondline temperature by an additional 2.9 K.

Abstract Background In hepatocellular carcinoma (HCC), pulmonary metastasis (PM) after hepatectomy is associated with poor clinical outcomes. The crucial phases of tumour cell proliferation, angiogenesis, and metastasis all entail platelet activation. In HCC, platelet distribution width (PDW) suggests platelet size changes and predicts a worse prognosis. The aim of this study was to assess the association between PDW and PMs in HCC patients receiving hepatectomy. Material/methods From January 2013 to December 2015, a cohort of patients who underwent hepatectomy for HCC at the Harbin Medical University Cancer Hospital in China were retrospectively evaluated. The relationship between PDW levels and clinical and demographic parameters was examined. To investigate the relationships between predicted factors and PM, a competing risk model was used. From January 2016 to December 2018, a validation cohort of 109 patients from the First Affiliated Hospital of Harbin Medical University was studied independently. Results In the primary cohort, 19 out of 214 patients had postoperative PMs. In HCC patients with PM, PDW levels were lower than in those without PM. There was a significant difference in the cumulative incidence of 2-year PM between the high-PDW and low-PDW groups after controlling for competing risk events (death prior to the development of PM) (p

Abstract Background Intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) are the most prevalent histologic types of primary liver cancer. HCC and ICC differ in treatment and prognosis, warranting an effective differential diagnosis between them. This study aimed to explore the clinical value of mean platelet volume (MPV) to discriminate between HCC and ICC. Material/methods We performed a retrospective analysis of ICC and HCC patients who were from the Harbin Medical University Cancer Hospital, China. Logistic regression analysis was used to identify the independent factors for the differentiation of HCC and ICC. A receiver operating characteristic curve was built to evaluate the diagnostic performance of the potential model. An independent validation study was performed to validate the diagnostic ability. Results ICC patients were detected in 146 out of 348 patients in the primary cohort. MPV levels were decreased in ICC patients compared with those in HCC patients. Logistic regression analysis revealed that MPV was an independent factor in distinguishing HCC from ICC. A combination of sex, hepatitis B surface antigen, MPV, alpha-fetoprotein, and carbohydrate antigen 19–9 demonstrated a good capability to differentiate HCC from ICC. Similar results were achieved in the validation cohort. Conclusions MPV may be a new marker to help distinguish ICC from HCC. Further validation studies are required.

Background. Elevated platelet volume is the risk factor for the development and poor overall survival of colorectal cancer (CRC) patients. Both microsatellite status and platelet glycoprotein Ibα (GPIbα) are related to platelet volume in CRC patients. This study aimed to investigate platelet GPIbα ectodomain (termed glycocalicin) levels among CRC patients and the association between the glycocalicin levels and microsatellite status in CRC. Methods. The clinical and laboratory data of 430 CRC patients between January 2018 and December 2018 in Harbin Medical University Cancer Hospital were collected. The microsatellite status was determined with a polymerase chain reaction. The participants were separated into high microsatellite instability (MSI-H) and microsatellite stable (MSS) groups according to microsatellite status. The glycocalicin levels were measured with an enzyme-linked immunosorbent assay, and the cut-off point was determined with the receiver-operating characteristics curve. The clinical and pathological characteristics were collected via electronic medical records. Logistic regression was used to explore the association between glycocalicin and microsatellite status. Results. Among the 430 CRC patients enrolled, 64 patients (14.9%) were identified as MSI-H and others as MSS CRC. Glycocalicin levels were significantly reduced in patients with MSI-H than those with MSS. After controlling for potential confounders, logistic regression analysis revealed that glycocalicin levels were independently associated with MSI-H CRC. Conclusions. Reduced glycocalicin levels are associated with the MSI-H subtype of CRC. Further research is needed to elucidate the mechanisms of the association between glycocalicin and MSI-H in CRC patients.