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The thermoplastic cassava starch (TPS)/sisal fiber (SF) composites were prepared by melt blending. The effects of SF content and its surface treated by sodium hydroxide (NaOH) and silane coupling agent (KH550) on the thermal degradation behavior and structures of TPS were investigated by thermogravimetric‐mass spectrometry (TG‐MS), Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD) and nuclear magnetic resonance (NMR). The thermal decomposition temperatures of TPS/SF composites increase with the SF content. The thermal decomposition products of TPS/SF composites are mainly methane, H2O, acetylene, formaldehyde, methanol and CO2. The thermal stability of composites containing SF treated by NaOH is better than that of KH550. TPS/SF composites show A + V types crystal, and the sample containing SF treated by NaOH has the highest V type crystal. The experimental results reveal that the content and the surface of SF play an important role in the thermal stability and structures changes of TPS/SF composites.

The fatigue life and prediction of styrene-butadiene-styrene thermoplastic elastomer (SBS) under the action of uniaxial tension was investigated, and the fatigue fracture mechanism was analyzed. With the increases of amplitude and frequency, the fatigue life of SBS decreases. The fatigue life of SBS under the amplitude and frequency was predicted, and the shift factor was applied to predict the fatigue life of SBS at the other frequency and amplitude. With the increase of temperature, the fatigue life decreases first and then increases. The fatigue fracture surface presents crack source region, crack propagation region, and instantaneous fracture region. At – 40°C, the crack source region is rough, and the crack propagation region and instantaneous fracture region are rough with the rib morphology. With the increase of temperature at 23°C, the crack source region is relatively flat, and the crack propagation region presents the undulant surface. With the temperature further increased up to 50°C, the fracture surface is very flat, and the shell lines could be clearly seen. The crack growth rate of SBS increases with the increase of temperature. The gel structure of SBS is formed at high temperature through the chemical crosslinking.

Background: Human epidermal growth factor receptor 2 (HER2) is a landmark protein in determining the targeted treatment of breast cancer (BC). However, the latest research shows that different intensity of HER2 protein expression levels in BC leads to different clinical characteristics, treatment, and prognosis, especially in HER2 low expression patients. Therefore, this study intends to analyze and compare the clinicopathologic features and prognosis of BC patients with low and zero HER2 expression from The Cancer Genome Atlas (TCGA) database and the data collected by our center.Methods: First, the BC dataset was downloaded from TCGA database, including 345 eligible and with complete clinical information BC patients, to compare the difference between HER2 low expression groups and HER2 zero expression groups and their correlation with estrogen receptor (ER) and progesterone receptor (PR) expression. Then, the clinicopathological data and follow-up of 405 patients with HER2 low expression and HER2 zero expression diagnosed with BC admitted to the Affiliated Hospital of Youjiang Medical University for Nationalities (YJMU) from January 2017 to December 2021 were collected to verify the consistency of the results of the two data sets.Results: Both the clinical samples and the TCGA data showed that the ER and PR rates were higher in the HER2 low expression group compared with the HER2 zero expression group. There were no significant differences in tumor size, lymph node metastasis, distant metastasis, and disease-free survival (DFS). In addition, the data analysis of 405 clinical samples also showed that the HER2 low expression group had a lower 3-year recurrence or metastasis rate compared with the HER2 zero expression group.Conclusions: Compared with HER2 zero expression, HER2 low patients express more ER and PR, and have less short-term recurrence and metastasis, but there is no obvious difference in DFS between the two groups.

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