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Germanium (Ge) is a widely distributed but rare element on earth. Organic germanium is the most widely used form of germanium. Compared to the common metal (mercury, cadmium, lead, etc.), organic germanium is much less toxic to humans than others. Since its discovery in 1886, organic germanium and relative compounds have caused many medically related problems across the globe. In most cases, organic germanium exists in the natural environment in an oxidation state. The size of organic germanium and its compounds is extremely small in natural water, for which organic germanium can easily enter the environment through the flow of water. Because organic germanium owns unique chemical properties and is potentially ecotoxic, so there are have special environmental problems. Considering the fact that people does not know much about organic germanium, along with the lack of systematic research, this paper starts with a brief introduction of the chemical composition, distribution, and threat to human health of organic germanium. Then, the new and common technologies for the recovery and removal of germanium as referred to in various literatures introduced and with detail description of their performance, advantages, disadvantages, and applications. It is of great significance for people to understand organic germanium and its pollution control. [ABSTRACT FROM AUTHOR]

A newly discovered Devonian ophiolite located in the Taoxinghu area of central Qiangtang on the Qinhai–Tibet Plateau is described. The ophiolite consists of gabbro and diabasic dikes, and invasive cumulate gabbros-leucogabbros. The ophiolite has undergone greenschist facies metamorphism and minor deformation. Dating of the metagabbro by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) zircon U–Pb techniques yielded a weighted mean age of 367.2 ± 3.3 Ma (Late Devonian). Whole-rock geochemical analyses show that the rocks belong to the tholeiite series, with weak depletion in light rare-earth elements (LREEs), almost no Eu anomalies, weak enrichment in large-ion lithophile elements (LILEs), depletion in Nb and Ta, and weak negative Hf and Ti anomalies. These characteristics are similar to those of back-arc basin basalts. Together, these characteristics suggest that the rocks of the Devonian ophiolite formed by ~30% partial melting of spinel lherzolite, which was enriched by interaction with aqueous fluids during the late-generation phases; there is no evidence of subduction-related melting. The Devonian ophiolite rocks in the Taoxinghu area were first discovered in the LongmuCo–Shuanghu–Lancang suture zone. Detailed geochemical analyses show that the rocks formed in a back-arc ocean basin environment, indicating that the LongmuCo–Shuanghu–Lancang suture zone in central Qiangtang represents a Late Devonian intra-oceanic subduction zone in the Palaeo–Tethys Ocean. The discovery of the central Qiangtang Devonian ophiolite provides essential data for understanding the evolutionary history of the Palaeo–Tethys Ocean, and for identifying and understanding the roles of the different tectonic units on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Green manuring is a common practice in replenishment of soil organic matter and nutrients in rice paddy field. Owing to the complex interplay of multiple factors, the oxidation–reduction (redox) properties of dissolved organic matter (DOM) from green manure crops are presently not fully understood. In this study, a variety of surrogate parameters were used to evaluate the redox capacity and redox state of DOM derived from Chinese milk vetch (CMV,Astragalus sinicusL.) via microbial decomposition under continuously flooded (CF) and non-flooded (NF) conditions. Additionally, the correlation between the surrogate parameters of CMV–DOM and the kinetic parameters of relevant redox reactions was evaluated in a soil–water system containing CMV–DOM. Results showed that the redox properties of CMV–DOM were substantially different between the fresh and decomposed CMV–DOM treatments. Determination of the surrogate parameters via ultraviolet–visible/Fourier transform infrared absorption spectroscopy and gel permeation chromatography generally provided high-quality data for predicting the redox capacity of CMV–DOM, while the surrogate parameters determined by elemental analysis were suitable for predicting the redox state of CMV–DOM. Depending on the redox capacity and redox state of various moieties/components, NF-decomposed CMV–DOM could easily accelerate soil reduction by shuttling electrons to iron oxides, because it contained more reversible redox-active functional groups (e.g. quinone and hydroquinone pairs) than CF-decomposed CMV–DOM. This work demonstrates that a single index cannot interpret complex changes in multiple factors that jointly determine the redox reactivity of CMV–DOM. Thus, a multi-parametric study is needed for providing comprehensive information on the redox properties of green manure DOM. [ABSTRACT FROM PUBLISHER]

T-cell immunoglobulin- and mucin-domain-containing molecule-3 (Tim-3) is preferentially expressed on Th1-helper type T-cells and functions to repress the Th1-mediated immune response. However, the role of Tim-3 during the inflammatory pathogenesis of asthma remains unclear. This study determines the expression level of Tim-3 in CD4+ T-cells within the peripheral blood and bronchoalveolar lavage fluid (BALF) isolated from a murine model of atopic asthma and explores the potential role of Tim-3 during the inflammatory response. Mice were randomly divided into normal control, asthma day 1, and asthma day 7 groups, and peripheral blood T lymphocytes and BALF cells were collected. The ratio of Tim-3+/CD4+ cells among the total CD4+cell populations from peripheral blood and BALF was determined by flow cytometry, and the expression of the Tim-3 mRNA was determined by Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). In contrast with the normal control group, the ratio of Tim-3+/CD4+:CD4+ cells and the level of Tim-3 mRNA in both the peripheral blood T lymphocytes and BALF cells among the asthma day 1 and asthma day 7 groups were significantly increased ( p < 0.01), and those in the asthma day 7 group were higher than the asthma day 1 group ( p < 0.05). There was also a positive correlation between the ratio of Tim-3+/CD4+:CD4+ detected in BALF and that the ratio detected in peripheral blood T lymphocytes (r = 0.84, p < 0.01). Therefore, the expression of Tim-3 is increased in CD4+ T-cells following airway challenge and likely affects asthma-induced inflammation by repressing the Th1-mediated immune response. [ABSTRACT FROM AUTHOR]