Petrogenesis and tectonic significance of mafic–ultramafic rocks from Southwest Yunnan, China

This study focuses on the mafic–ultramafic lavas of the Early Carboniferous outcrop in Mangxin, southwestern Yunnan, China. Picrites with 26–32 wt% MgO and a quenched texture are the most significant components of this rock association. This article divides the Mangxin picrites into two types. The mantle potential temperature ($T_{{p}}$) of these picrites is higher than the $T_{{p}}$ range of mid-ocean ridges and reaches that of mantle plumes. According to the geochemical characteristics, the Type-1 picrites probably formed from the melting of the mantle plume head and were contaminated by ambient depleted mantle, whereas the Type-2 picrites formed from the melting of mantle plume tails. These plume-related mafic–ultramafic rocks in Mangxin and the ocean island basalt (OIB)-carbonate rock associations in many areas of the Changning–Menglian belt provide significant evidence for the improvement of previous models of the Palaeotethyan oceanic plateau

Petrogenesis and tectonic significance of mafic–ultramafic rocks from Southwest Yunnan, China

This study focuses on the mafic–ultramafic lavas of the Early Carboniferous outcrop in Mangxin, southwestern Yunnan, China. Picrites with 26–32 wt% MgO and a quenched texture are the most significant components of this rock association. This article divides the Mangxin picrites into two types. The mantle potential temperature ($T_{{p}}$) of these picrites is higher than the $T_{{p}}$ range of mid-ocean ridges and reaches that of mantle plumes. According to the geochemical characteristics, the Type-1 picrites probably formed from the melting of the mantle plume head and were contaminated by ambient depleted mantle, whereas the Type-2 picrites formed from the melting of mantle plume tails. These plume-related mafic–ultramafic rocks in Mangxin and the ocean island basalt (OIB)-carbonate rock associations in many areas of the Changning–Menglian belt provide significant evidence for the improvement of previous models of the Palaeotethyan oceanic plateau

Computational Thermodynamics and Kinetics in Materials Modelling and Simulations

Over the past two decades, Computational Thermodynamics and Kinetics have been tremendously contributed to materials modeling and simulations and the demands on quantitative conceptual design and processing of various advanced materials arisen from various industries and academic institutions involved in materials manufacturing, engineering and applications are still rapidly increasing

Expression of hypoxia inducible factor-1α and vascular endothelial growth factor-C in human chronic periodontitis

AbstractBackground/purposeEvidence shows that there is a relationship between hypoxia and inflammatory response in periodontitis. Hypoxia-inducible factor (HIF)-1α is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. Although experimental results demonstrate an association between HIF-1α and vascular endothelial growth factor (VEGF)-C in tumor angiogenesis, the role of HIF-1α and VEGF-C in the pathogenesis of periodontitis is still ambiguous. So far, limited attention has been given to the role of hypoxia and VEGF-C in periodontitis. The present study aimed to investigate the expression and distribution of HIF-1α and VEGF-C in gingival tissue samples from patients with different stages of chronic periodontitis and healthy individuals.Materials and methodsA total of 56 samples were involved in this study, including moderate chronic periodontitis (n = 20), advanced chronic periodontitis (n = 20), and healthy control tissues (n = 16). The gingival specimens were stained with hematoxylin and eosin for histopathology. The expression of HIF-1α and VEGF-C in gingival tissues was detected by immunohistochemical staining.ResultsHIF-1α and VEGF-C were found in gingival tissues from patients with different stages of chronic periodontitis as well as healthy control tissues. HIF-1α protein was expressed mainly in the epithelial layer of gingival tissues, and VEGF-C protein was mostly located in the connective tissue papilla of gingival tissues. Compared with healthy controls, the expression of HIF-1α and VEGF-C in chronic periodontitis groups was significantly higher (P < 0.01), and the density of HIF-1α and VEGF-C in advanced chronic periodontitis group was even significantly higher than that in the moderate chronic periodontitis group (P < 0.01).ConclusionOur results suggest that the expression of HIF-1α and VEGF-C increased with severity of periodontitis. So, we conclude that HIF-1α may play an important role in the pathophysiology of human periodontitis and may be related to the function of VEGF-C during periodontitis

Tribological properties of surface dimple-textured by pellet-pressing

AbstractSurface texturing is thought to be as an effective tribological method of decreasing friction coefficient of contact pairs. Firstly, AISI1045 steel surface is dimple-textured by a convenient and economical way of pellet-pressing, then, the textured and polished samples is against SiC ball lubricated by engine oil to carry out tribological tests in reciprocating mode in tribomachine type UMT-II. It is concluded that surface dimple-texture made by pellet-pressing is beneficial to improve tribological properties lubricated by engine oil under10N load and 5mm/s sliding speed