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The large Yueyang Ag-Au-Cu deposit is commonly regarded as a low-sulfidation epithermal deposit in the Zijinshan orefield, Fujian Province, southeastern China. The Ag-Ag-Cu orebodies hosted in the Zijinshan granitic batholith are mainly stratoid and lens in shape, and controlled by a series of NW-trending listric faults with shallow dip angles. Four mineralization stages are recognized on the basis of mineral assemblage, ore fabrics, and crosscutting relationships of the ore veins, namely: pre-ore (pyrite + sericite + quartz ± chlorite), main Cu (chalcopyrite + pyrite + sericite + quartz ± bornite), main Ag-Au (Ag and Au minerals + pyrite + quartz + adularia ± calcite ± apatite ± chalcopyrite ± galena ± sphalerite) and post-ore (quartz ± chalcedony ± calcite) stages. Fluid inclusions (FIs) in the deposit include aqueous liquid-rich (WL-), aqueous vapor-rich (WV-), and minor carbonic (C-) and daughter mineral-bearing (S-) type ones. WL-subtype is the main inclusion type in the Yueyang deposit, accounting for more than 90% in proportion in each stage. Minor WV-subtype inclusions occur in both the main Cu and Ag stages, while the C-type and S-type ones are only observed in the main Cu stage. Fluid inclusion and H-O isotope study indicated that the ore-forming fluid of the main Cu stage is primarily magmatic vapor, which further underwent fluid boiling and mixing with meteoric water, while the ore-forming fluid of the main Ag stage is meteoric water-dominated, and the precipitation of silver and gold was mainly resulted from fluid boiling and the precipitation of other sulfides. On the basis of the aforementioned geological, fluid inclusion and stable isotope studies, we proposed a two-stage model for the Yueyang deposit, including a magmatic vapor-related porphyry type Cu mineralization and meteoric water-related low-sulfidation epithermal Ag-Au-Cu mineralization, although the porphyry Cu mineralization is very limited in scale. The mineralization and exhumation depths of the Yueyang deposit are estimated to be 448‒527 m and 18‒97 m, respectively. By comparison with the exhumation depths of other deposits in the Zijinshan orefield, it is suggested that more epithermal deposits could be found in the southwest of the orefield due to less uplift and exhumation therein. [ABSTRACT FROM AUTHOR]

• A novel strain of infectious bronchitis virus (CK/CH/FJ/202005) caused severe air sacculitis in 1- and 15-day-old challenged SPF chickens. • Tracheal and air-sac lesions were first evident at 5 DPI, and persisted throughout the 30-day experiments. • In the 1-day-old infected group, the viral titer in the trachea was above 104 at 5, 7, 10, and 15 DPI, and then dropped rapidly during the third week. Infectious bronchitis virus (IBV) has a significant impact on the poultry industry, and genogroup VI (GVI) IBVs, such as the TC07−2 strain, were reported in China since 2007. We isolated a novel strain, CK/CH/FJ/202005 (henceforth 202005), from broilers that were vaccinated with different attenuated IBV strains (H120, 4/91, or QX) in Fujian, China during 2020. Based on comparison with the SNU8065 strain (GI-22), the 1ab genes were the locations of recombination in this new isolate. Pathogenicity testing of 1-day-old and 15-day-old specific pathogen-free (SPF) chickens indicated varying severities of air sacculitis beginning 5 days-post-inoculation (DPI). Histopathological analysis indicated that tracheal lesions started at 5 DPI and persisted throughout the 30-day experiments in 1-day-old infected chickens. Virus re-isolation and viral load tests indicated this strain was mainly in the trachea, and not the kidneys. Our findings showed that the 202005 strain was pathogenic in 1-day-old and 15-day-old chickens. These results should be considered when developing strategies to control IBV infections. [ABSTRACT FROM AUTHOR]

Abstract: Sewage sludge (SS) is used on sloping land, as a soil amendment, because of its organic matter (OM) and nutrient content. However, the presence of nitrogen (N), in acidic soils amended with sludge, and its transport in runoff can lead to eutrophication of downstream surface water. This study assesses the effects of different application methods on N transport, via runoff from plots amended with SS (0 and 120Mgha−1). A lateritic red soil (pH 5.2) was selected for this study, using simulated rainfall conditions. When sludge was broadcasted and mixed with surface soils (BM), the concentrations and mass losses of total N in the mixed sample (MTN), total N in the settled sample (STN), total particulate N (TPN), total suspended N (TSN), total dissolved N (TDN) and NH4 +-N, in runoff water, were highest at 1 or 18d after application. BM treatments showed initial pollution risks to surface waters, which diminished gradually with time. Whereas the concentrations and mass losses of NO3 −-N, in all sludge plots, appeared to have a declining trend, after an initial ascent. Hole-application (HA) and broadcast application with hay mulch (BH) treatments prevented N loss effectively, the runoff losses coefficient of MTN increased in the order BM (0.43%)>HA (0.15%)>BH (0.03%). For sludge treatments, N was largely lost in dissolved species, while a large portion of NH4 +-N was lost in particulate fraction. Nitrogen (N) losses in runoff were greatly affected by the transformation of sludge N in the soil and the modification of soil properties, induced by sludge amendment. The risk associated with the application of sludge to sloping fields, in areas of acidic soil, is an important research subject that merits further study. [Copyright &y& Elsevier]

The Shibei pluton is a Late Jurassic granitic body in the South China Block (Fujian province), featured by macroscopically isotropic granite and undeformed margins, which are also characteristics for most of the Late Jurassic plutons in southeastern China. Our field observations, fabric investigations and gravity modelling allow us to decipher the internal structure, overall geometry, magma accumulation and emplacement processes of the Shibei pluton. Magnetic fabrics of the Shibei pluton can be divided into two distinct groups. The first one, observed in the southern-central part of the pluton, is characterized by high-angle to sub-vertical (54°-90°) NE-SW-striking magnetic foliations and variably plunging magnetic lineation. The second group, recognized in the northern part of the pluton, shows variably dipping (22°-88°) magnetic foliation, which generally strikes subparallel to pluton-country rock contacts, and irregularly oriented magnetic lineation. The Bouguer gravity modelling demonstrates that the pluton has a tabular geometry with a N-S-striking long axis, and a length-width-thickness ratio of ~32:8:1. The intrusion thickness gradually decreases from the southwest margin (ca. 2.5 km) to the northeast margin (ca. 0.5 km). Moreover, an undulating bottom with one or more convex intruding roots can be observed. Integrating published geochronological and regional tectonic data, we propose that the Shibei pluton was constructed by successive NE-SW-striking magma injections. Emplacement of early magma batches started in the SW part of the pluton by magma injection, which was guided by inherited structures produced by pre-emplacement tectonic events. Continuous magma injections were laterally accreted to earlier emplaced magma intrusions, and/or injected along lithological and/or structural discontinuities within the country rocks at upper crustal level without producing ductile deformation in the pluton-country rock contact zone. Our structural and fabric investigations indicate that the SE South China Block was not subjected to a major tectonic deformation during the Late Jurassic period. • Emplacement of the Shibei pluton was assisted /guided byinherited structures produced by pre-emplacement tectonic events. • The pluton was formed by several NE-SW-striking magma injections started in the SE part of the pluton and northward accretion. • The SE part of the South China Block is under a tectonic quiescence setting during late Jurassic epoch. [ABSTRACT FROM AUTHOR]