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© 2019 Elsevier Ltd Metallic composition of diesel particulate matter, even though a relatively small proportion of total mass, can reveal important information regarding engine conditions, fuel/lubricating oil characteristics and for health impacts. In this study, a detailed investigation into the metallic elemental composition at different particle diameter sizes has been undertaken. A bivariate statistical analysis was performed in order to investigate the correlation between the metallic element, measured engine performance and engine emission variables. Major sources of metallic elements in the emitted particles are considered in this study, including the fuel and lubricating oil compositions, engine wear emissions and metal-containing dust in the ambient air. Metallic solid ultrafine-particles (Dp < 100 nm) are strongly associated with metallic compounds derived from lubricating oil (Ca, Zn, Mg and K), while the fuel related metallic compounds and engine wear emissions are represented in the accumulation mode particle fraction (>100 nm). Calculated correlation matrices show a clear effect of engine load conditions and fuel S contents on particle number and mass emissions.

Chuanshu Yuan, Kai Yang, Hong Tang, Dan Chen Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China Background: At present, the research on serum tumor markers in the early diagnosis of malignant tumors has aroused widespread concern. The aim of this study was to investigate the diagnostic values of serum tumor markers cytokeratin 19 fragment (Cyfra21-1), squamous cell carcinoma antigen (SCCAg), ferritin, carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and α-fetoprotein (AFP) for patients with oral/oropharyngeal squamous carcinoma (OSCC/OPSCC). Methods: One hundred and sixty-nine cases of patients with OSCC/OPSCC as the experimental group, 86 cases of oral benign tumor patients as the control group, and 30 cases of healthy people as the normal control group were studied. The levels of serum Cyfra21-1, SCCAg, ferritin, CEA, CA19-9, and AFP were measured using electrochemiluminescence immunoassay. Results: The levels of serum Cyfra21-1, SCCAg, ferritin, and CEA in patients with OSCC/OPSCC were significantly higher than those of benign tumor and healthy control group (P0.05). The level of serum Cyfra21-1 in patients with early OSCC/OPSCC (stage I + II) was significantly higher than that of benign tumor and healthy control group (P0.05). The levels of serum Cyfra21-1, SCCAg, ferritin, and CEA in the middle-late stage of patients with OSCC/OPSCC (stage III + IV) were significantly higher than those of patients with the early OSCC/OPSCC, benign tumor, and healthy control group (P