Hydrodynamic Links between Shallow and Deep Mineralization Systems and Implications for Deep Mineral Exploration

Deep mineral exploration is increasingly important for finding new mineral resources but there are many uncertainties.Understanding the factors controlling the localization of mineralization at depth can reduce the risk in deep mineral exploration.One of the relatively poorly constrained but important factors is the hydrodynamics of mineralization.This paper reviews the principles of hydrodynamics of mineralization,especially the nature of relationships between mineralization and structures,and their applications to various types of mineralization systems in the context of hydrodynamic linkage between shallow and deep parts of the systems.Three categories of mineralization systems were examined,i.e.,magmatic-hydrothermal systems,structurally controlled hydrothermal systems with uncertain fluid sources,and hydrothermal systems associated with sedimentary basins.The implications for deep mineral exploration,including potentials for new mineral resources at depth,favorable locations for mineralization,as well as uncertainties,are discussed.

具有骨样微环境的压电催化可控矿化支架实现内源性骨再生

Orderly hierarchical structure with balanced mechanical,chemical,and electrical properties is the basis of the natural bone microenvironment.Inspired by nature,we developed a piezocatalytically-induced controlled mineralization strategy using piezoelectric polymer poly-L-lactic acid(PLLA)fibers with ordered micro-nano structures to prepare biomimetic tissue engineering scaffolds with a bone-like microenvironment(pcm-PLLA),in which PLLA-mediated piezoelectric catalysis promoted the in-situ polymerization of dopamine and subsequently regulated the controllable growth of hydroxyapatite crystals on the fiber surface.PLLA fibers,as analogs of mineralized collagen fibers,were arranged in an oriented manner,and ultimately formed a bone-like interconnected pore structure;in addition,they also provided bone-like piezoelectric properties.The uniformly sized HA nanocrystals formed by controlled mineralization provided a bone-like mechanical strength and chemical environment.The pcm-PLLA scaffold could rapidly recruit endogenous stem cells,and promote their osteogenic differentiation by activating cell membrane calcium channels and PI3K signaling pathways through ultrasound-responsive piezoelectric signals.In addition,the scaffold also provided a suitable microenvironment to promote macrophage M2 polarization and angiogenesis,thereby enhancing bone regeneration in skull defects of rats.The proposed piezocatalytically-induced controllable mineralization strategy provides a new idea for the development of tissue engineering scaffolds that can be implemented for multimodal physical stimulation therapy.