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Anorthite crystallization between the body and glaze of ancient ceramics has regional characteristics. According to the microstructural characteristics of the body and glaze, ancient Chinese ceramics can be mainly divided into four types: Yue kiln type, Longquan kiln type, Ding kiln type and Changsha kiln type. Anorthite crystallization is closely related to the elemental composition of the body and glaze. The microstructure of Minhou kiln ceramic chips shows that when the Al2O3 content of the body is high, fine feldspar crystals precipitated into the layer of molten glaze in contact with the body surface during firing. This unique microstructure can help identify some ceramics.

Strata of different geological periods extensively outcrop in western Guangdong Province, but most gold deposits are restricted to the Middle-Late Proterozoic Yunkai Group and the Cambrian Bacun Group, showing obvious strata-bound characteristics. Gold abundance and trace element geochemistry of the Yunkai and Bacun Groups are compared with those of the Ordovician and Silurian strata. The Yunkai Group is considered to be the source strata for gold mineralization in the region.

Organic anion transporters (OATs), as one group of the important Drug/xenobitic transporters, play vital roles in the body disposition of environmental toxins and clinically anionic drugs. Numerous works have forged an extensive framework on OATs. However, more works are required to explore the functionally critical amino acid residues and motifs to glean comprehensive information on relationship between structure and function. In the first part of the thesis, we investigated the role of dileucine (L6L7) at the amino terminus of hOAT1 and GXXXG motifs in its transmembrane domains 2 (G144XXXG148) and 5 (G223XXXG227) of hOAT1 in the expression and function of the transporter by using mutants made by site-directed mutagenesis approach. Mutant transporter L6A/L7A, G144A and G148A showed no transport activity due to its complete loss of surface expression. Proteasomal inhibitor and lysosomal inhibitor treatment suggested the mutant L6A/L7A- G144A- and G148A transporters were degraded through proteasomal pathway. Treatment of L6A/L7A- expressing cells with two chemical chaperones could not repair the misfolding of the mutant transporter in Endoplasmic Reticulum. For mutant transporters G223A and G227A, only G227 showed dramatic reduced transport activity due to dramatic loss in expression. Proteasomal or lysosomal inhibitors resulted in partial recovery of total cell expression of the mutant G227A hOAT1, but not recovery of surface expression and function. Our data suggest that the L6L7 and GXXXG motifs in transmembrane domains 2 and 5 play critical roles in the stability of hOAT1. Our lab has reported that activation of protein kinase C (PKC) leads to accelerated internalization of hOAT1. However the underlying mechanism is still unclear. In the second part of the thesis, we indentified that ubiquitination of hOAT1 was significantly increased after PKC activation by phorbol 12-myristate 13-acetate (PMA) and Angiotensin II (AngII). And the PKC-induced ubiquitination of a mutant N5KR carrying multiple lysine substitutions was abolished. Importantly, cell surface biotinylation experiments showed that the N5KR mutant which has the minimal ubiquitination counteracted against the enhanced retrieval and accelerated degradation of surface hOAT1 proteins by PKC activation, which established a strong correlation of PKC-dependent endocytosis and PKC-dependent ubiquitination of hOAT1.

Cassiterites from both the Beauvoir and Montebras granites of France are typically rich in trace elements such as Nb and Ta, and contain quite a number of inclusions of columbite (dominantly manganocolumbite). Two thin sections of cassiterite crystals have been prepared for Raman microprobe analysis. The spectra obtained from different parts of the cassiterites show that the vibration frequency of the Aig peak decreases with increasing Nb. Ta, Fe and Mn atomic contents. It is worthy to note that a new peak (named the “An peak”) has been reported for the first time in the part with oriented columbite inclusions. The vibration frequency varies from 827 to 830 cm-1. The presence of the new peak may be attributed to structural changes of cassiterite due to the excess of Nb and Ta in the lattice and the exsolution of columbite inclusions in cassiterite.

Human organic anion transporter hOAT1 plays a critical role in the body disposition of environmental toxins and clinically important drugs including anti-HIV therapeutics, anti-tumor drugs, antibiotics, anti-hypertensives, and anti-inflammatories. In the current study, we investigated the role of dileucine (L6L7) at the amino terminus of hOAT1 in the expression and function of the transporter. We substituted L6L7 with alanine (A) simultaneously. The resulting mutant transporter L6A/L7A showed no transport activity due to its complete loss of expression at the cell surface. Such loss of surface expression of L6A/L7A was consistent with a complete loss of an 80 kDa mature form and a dramatic decrease in a 60 kDa immature form of the mutant transporter in the total cell lysates. Treatment of L6A/L7A-expressing cells with proteasomal inhibitor resulted in a significant increase in the immature form of hOAT1, but not its mature form, whereas treatment of these cells with lysosomal inhibitor had no effect on the expression of the mutant transporters, suggesting that the mutant transporter was degraded through proteasomal pathway. The accumulation of mutant transporter in the endoplasmic reticulum (ER) was confirmed by coimmunolocalization of L6L7 with calnexin, an ER marker. Furthermore, treatment of L6A/L7A-expressing cells with sodium 4-phenylbutyrate (4PBA) and glycerol, two chemical chaperones, could not promote the exit of the immature form of the mutant transporter from the ER. Our data suggest that L6L7 are critical for the stability and ER export of hOAT1.