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The West Kunlun orogenic belt (WKOB) is a complex orogenic belt that preserves the evidence of Early Palaeozoic and Late Palaeozoic orogenic events, with the former resulting from the closure of the Proto-Tethys Ocean. To better reveal the relationships between Early Palaeozoic granitoids in the WKOB and the tectonic evolution of the Proto-Tethys Ocean, we analysed the rocks of Akedala pluton, which is exposed within the Qiaerlong basin, and compared the results with contemporaneous magmatic rocks elsewhere in the WKOB. Integrated petrology, geochronology, and Sr–Nd–Hf isotope analyses of the rocks revealed the following: (1) The Akedala pluton is mainly composed of metaluminous–peraluminous I-type quartz monzonite and monzogranite; U–Pb dating of zircon indicates that quartz monzonite and monzogranite components is emplaced at 473–479 Ma and 462 Ma, respectively. (2) Both of them were enriched in large-ion lithophile elements and light rare earth elements and depleted in high field strength elements with negative Nb, Ta, Zr, P and Ti anomalies, indicating that they formed in a subduction zone environment. (3) Quartz monzonites were enriched in MgO concentrations (>3.10 wt.%), and show variable whole rock Sr-Nd isotopic ratios ((87Sr/86Sr)i = 0.7042–0.7058, εNd(t) = – 0.4 to +1.1), and had positive zircon εHf(t) (+0.0 to +6.8) values, which suggests they are derived from a mixed source of juvenile crust and older lower crust. (4) Monzogranites were characterized by high Sr (461–804 ppm) and low Y (2.00–3.68 ppm) and Yb (0.19–0.31 ppm) contents with high Sr/Y (164–325) and (La/Yb)N (12.6–46.7) ratios, indicating an adakitic affinity; they had relatively homogeneous whole rock (87Sr/86Sr)i (0.7044–0.7045) and positive εNd(t) (+2.0 to +2.9) and positive zircon εHf(t) (+1.1 to +4.3) values with low MgO, Cr, Ni and Nb contexts, suggesting that they were mainly generated from partial melting of thickened lower crust. Comparative analysis of these results with other Early Palaeozoic arc magmas in the WKOB shows that the Akedala pluton was formed due to the southward subduction of the Proto-Tethys Ocean. Divergent bidirectional subduction of the Proto-Tethys Ocean was initiated in the Early Cambrian, continued through the Middle Ordovician, and ended in the Early Silurian, due to terminal collision between the Tarim block and the West Kunlun terrane, which created the Early Palaeozoic orogenic belt. [ABSTRACT FROM AUTHOR]

Using grounded theory and the method of questionnaire surveys, etc., the influence of theme songs in sports events was studied from the perspective of consumers' perception. It states that the influence of sports event theme songs includes the four perception dimensions, that is, the event scene display, the emotion induction, the meaning symbolism, and the aesthetic sense of the songs. In terms of the degree of the influence on the event evaluation, the event scene display has the highest impact, followed by the event emotion induction, the meaning symbolism, and the aesthetics in the songs. Apart from the event scene display, the perceived event quality partly plays a mediating role in the other three paths. It is proposed that the use of sports auditory marketing tools should be emphasized, the dissemination effect of sports event theme songs be optimized from the four dimensions discussed above, and the role of event perception quality be especially strengthened. [ABSTRACT FROM AUTHOR]

For low carbon-to-nitrogen ratio municipal wastewater, full utilization of carbon sources is positive in reducing carbon emissions and carbon source addition. This study evaluated and proposed appropriate anaerobic duration control to improve nitrogen and phosphorus removal performance in Denitrifying Phosphorus Removal and Partial Denitrification coupled with Anammox (DPR-PDA) system. Excessive anaerobic duration resulted in wasted carbon source, anaerobic stage should be stopped after carbon source had been utilized. Hydraulic Retention Time-Anaerobic (HRT-An) of R1 was shortened from 5h to 0.56h, while R2 was maintained at 5h. The removal efficiency of nitrate (NO 3 −) were 91.7% in R1 and 71.5% in R2. Peak of NO 2 − accumulation (Peak-NO 2 --N) during denitrification in R1 was 4.5 times than in R2. Candidatus_Brocadia as anammox bacteria was self-enriched, the abundance in R1 was 4.67 times than in R2. This provided a practical guide for optimization of wastewater treatment processes and application of anammox technology. [Display omitted] • The effect of HRT-An on N and P removal was examined in two DPR-PDA systems. • Re-NO 3 --N of R1 (HRT-An: 5. → 0.56h) and R2 (HRT-An: 5h) were 91.7% and 71.5%. • Peak-NO 2 --N during denitrification process in R1 was 4.5 times higher than in R2. • Candidatus_Brocadia was self-enriched, abundance in R1 was 4.67 times than in R2. [ABSTRACT FROM AUTHOR]

The northern South China Sea continental margin is the key or critical segment of the Ocean-Continent Connection Zone (OCCZ) of the Great South China Block' the junction between the Tethyan and the (Paleo-) Pacific dynamic systems' and the interaction area between the Indian Ocean and the Pacific Ocean. However' due to the low-degree geophysical exploration in the past' the regional tectonic background' processes and mechanism of the transition between the Tethyan and the Pacific tectonic domains are unclear. Based on the latest large number of seismic profiles' we focus on the Cenozoic basin structure in the continental margin of the northern South China Sea and try to reveal the Mesozoic basement structures of the northern South China Sea continental margin, with the aim of exploring the pre-Cenozoic tectonic evolution and the Cenozoic opening, spreading, ridge fossil and closure of the South China Sea oceanic basin, so as to serve the accurate oil and gas exploration in this area at the same time. The seismic interpretation of the Pearl River Mouth Basin and the field structural investigation of the South China continental margin show that the OCCZ of the South China Block has experienced three processes: Mesozoic Indosinian collisional orogeny, Early Yanshanian accretionary orogeny and Late Yanshanian transpressive orogeny. During the Cenozoic era, it experienced the dispersive extension into basins under the control of NW-SE-directed normal extension in the early stage, the dextral pull-apart into basins under the control of NE-NNE-trending strike-slip faults in the middle stage, and the sinistral pull-apart into basins under the control of NW-WNW strike-slip faults in the late stage. In general, the transition process from the Tethyan to the Pacific tectonic systems can be subdivided into four stages: the transition from the Paleo-Tethyan to the Neo-Tethyan tectonic systems, the transition from the Neo-Tethyan to the Paleo-Pacific tectonic systems, the transition from the Neo-Tethyan to the Pacific tectonic systems, and the transition from the Paleo-Pacific to the Pacific tectonic systems. The tectonic transition of the East Asian OCCZ reflects the long-term mechanism of the Earth plate dynamic system driving the plate superconvergence in East Asia, in particular of the importance of the deep or submarine "Triple Poles", the Southeast Asian U-shape subduction system, the Pacific LLSVP and the African LLSVP. More importantly, the Southeast Asian U-shape subduction system is also one of the important dynamic engines of the Earth plate motion. [ABSTRACT FROM AUTHOR]