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Pucheng district is a part of the Wuyi Mountain polymetallic metallogenic belt, which is constituted by Archean-Proterozoic metamorphic basements and Mesozoic volcanic-sedimentary covers. Uranium deposits are formed as volcanic-hosted and structural controls. In this study, the hybrid data-driven methods of logistic regression (LR) and weights of evidence (WofE) were applied for the mineral potential mapping of uranium in the Pucheng district. Evidential layers such as volcanic stratum, structure, igneous rock, alteration and radioactive anomaly were used in the mineral prospectivity analyses. The results show that the data-driven methods can not only measure the relative importance of each type of geological feature in uranium controls but also delineate prospective grounds for uranium exploration. The receiver operating characteristics (ROC) curve and under the ROC curve (AUC) were applied to measure the performance of the prospectivity models. The data-driven models are highly capable of mapping uranium prospectivity because AUC is close to 1. The results show that more than 90% of the known uranium deposits occur in regions with high probability. LR performs a little better than WofE in this area. The prospectivity mapping confirmed that there is significant potential for uranium mineralization for further exploration. [ABSTRACT FROM AUTHOR]

Background: Non-neutropenic pulmonary aspergillosis is one of the most common and serious fungal infections. Previous studies have shown that single nucleotide polymorphisms (SNPs) of pattern recognition receptors genes are associated with susceptibility to aspergillosis. NOD-like receptors (NLRs) play an important role in the immunological response against fungal infection. In this study, we investigated the relationship between polymorphisms of three NLRs and susceptibility to pulmonary aspergillosis disease in non-neutropenic patients. Methods: We included 73 patients with proven pulmonary aspergillosis and 103 healthy controls. A total of sixteen SNPs in the NLRP3, NLRC4, and NLRC5 genes were detected by PCR-direct sequencing. Then, we evaluated the association between these polymorphisms and susceptibility to aspergillosis. Results: Fifteen SNPs were consistent with Hardy–Weinberg equilibrium except for NLRP3 rs7525979. A total of eight SNPs (NLRP3 rs3806265, NLRC4 rs212704 and NLRC5 rs1684579, rs12598522, rs3995817, rs3995818, rs34531240, rs28438857) were observed an association with susceptibility of pulmonary aspergillosis. The CC homozygote of NLRP3 rs3806265, TT homozygote of NLRC5 rs1684579 and T allele of NLRC5 rs12598522 were associated with a higher risk of aspergillosis while TT homozygote of NLRC4 rs212704 was associated with a lower risk of aspergillosis. Especially in the invasive pulmonary aspergillosis subgroup, the TT homozygote of NLRC5 rs1684579 and rs3995817, the CC homozygote of NLRC5 rs34531240 and rs28438857, GG homozygote of NLRC5 rs3995818, the C allele and CC homozygote of NLRP3 rs3806265 were associated with higher susceptibility. Conclusions: This study showed an association between polymorphisms of NLRP3, NLRC4, and NLRC5 and susceptibility to pulmonary aspergillosis for the first time. Further investigations in larger populations are needed, and functional studies are also required to investigate the function of these NLRs in aspergillosis, as well as other fungal infection diseases. [ABSTRACT FROM AUTHOR]

As a product of hydrothermal activity, seafloor polymetallic sulfide deposit has become the focus of marine mineral exploration due to its great prospects for mineralization potential. The mineral prospectivity mapping is a multiple process that involves weighting and integrating evidential layers to further explore the potential target areas, which can be categorized into data-driven and knowledge-driven methods. This paper describes the application of fuzzy logic and fuzzy analytic hierarchy process (AHP) models to process the data of the Southwest Indian Ocean Mid-Ridge seafloor sulfide deposit and delineate prospect areas. Nine spatial evidential layers representing the controlling factors for the formation and occurrence of polymetallic sulfide deposit were extracted to establish a prospecting prediction model. Fuzzy logic and fuzzy AHP models combine expert experience and fuzzy sets to assign weights to each layer and integrate the evidence layers to generate prospectivity map. Based on prediction-area (P-A) model, the optimal gamma operator (γ) values were determined to be 0.95 and 0.90 for fuzzy logic and fuzzy AHP to synthesize the evidence layers. The concentration-area (C-A) fractal method was used to classify different levels of metallogenic probability by determining corresponding thresholds. Finally, Receiver Operating Characteristic (ROC) curves were applied to measure the performance of the two prospectivity models. The results show that the areas under the ROC curve of the fuzzy logic and the fuzzy AHP model are 0.813 and 0.887, respectively, indicating that prediction based on knowledge-driven methods can effectively predict the metallogenic favorable area in the study area, opening the door for future exploration of seafloor polymetallic sulfide deposits. [ABSTRACT FROM AUTHOR]

The Laowan deposit is a typical gold deposit in the Qinling-Dabie metallogenic belt, which produces the most gold resources in Central China. After being explored for decades, follow-up exploration requires additional theoretical support. In this study, the factor analysis (FA) and spectrum–area (S–A) multifractal model were used to process multi-element geochemical data from 369 samples collected in the study area for identifying the geochemical anomalies associated with gold mineralization. The results showed that: (1) the mean Au content in this region is up to 1000 times higher than the Au background values of the upper crust of the South Qinling unit; (2) the factor analysis revealed that Au, Ag, Cu, As, Sb, and S can be used as direct ore-prospecting criteria; (3) the observed elemental zonation is consistent with the zonation of metallic elements in the magmatic–hydrothermal system. This supports the magmatic–hydrothermal origin of the Laowan deposit; (4) the spectrum–area fractal model can help to decompose the geochemical patterns in a complex geological setting. The decomposed geochemical anomaly map obtained by the S–A multifractal model indicated that highly anomalous areas have a great relationship with the Au occurrence and can be a guidance for further exploration in the study area. [ABSTRACT FROM AUTHOR]

The Xi'ao Cu-Sn polymetallic deposit is located in the inner alteration zone of the Laoka granite. The ore bodies extend to 400 m in the granite rock and primarily occur with fluorite and potassic alterations. Two cassiterite samples of altered rock-type ore and one tourmaline vein-type ore in the Xi'ao Cu-Sn polymetallic deposit yielded U-Pb ages of 83.3 ± 2.1 Ma, 84.9 ± 1.7 Ma, and 84.0 ± 5.6 Ma, respectively. The Raman spectrum peak values of A1g were shifted to a lower frequency, possibly due to the substitution of Sn with Nb, Ta, Fe, and Mn. Measured δ18O values of cassiterite samples and calculated δ18OH2O values for the ore-forming fluid indicate that the latter was mostly derived from magma. The high Fe and Mn abundances for cassiterite are consistent with those of hydrothermal origin. The Nb, Ta, and Ti contents indicate that cassiterites in the Xi'ao deposit likely formed in a metallogenic environment that was largely affected by granitic magmatism. Therefore, we conclude that the Xi'ao deposit is a magmatic hydrothermal deposit. [ABSTRACT FROM AUTHOR]