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The West Kunlun orogenic belt located in the northwestern margin of the Qinghai-Tibet Plateau is an important record of the formation and northward extension of the plateau, but the current research mainly focuses on the tectonic activities of the Cenozoic era, and there is still considerable controversy regarding the formation and evolutionary history of pre-Cenozoic orogenic belts. This study focuses on Cretaceous sandstone samples from the Kedong region in the piedmont belt of the West Kunlun orogenic belt. U-Pb geochronological analysis was performed on 200 detrital zircon grains from the core samples. Combined with stratigraphic data and previous research, the main provenance direction was investigated to constrain the tectonic evolutionary history of the orogenic belt's peripheral regions. The results show that the detrital zircons are aged from 290 to 208 Ma, 520-310 Ma, 810-580 Ma, 1,400-880 Ma and 2,548-1,730 Ma, reflecting the complexity of provenance in this area. Based on a comprehensive analysis of the characteristics of igneous rocks, zircon age composition and stratigraphic conditions in potential source areas, it is concluded that the primary source regions include the East Kunlun orogenic belt and the North and South Kunlun terranes, with a low likelihood of contributions from within the Tarim Basin. The evolution of the West Kunlun orogenic belt can generally be divided into two opening and two closing phases. The detrital zircon ages predominantly exhibit two peak values at 259 Ma and 459 Ma, respectively representing the ages of transition from oceanic crust subduction to continentcontinent collision for the Paleo-Tethys Ocean and the Proto-Tethys Ocean. Additionally, there is a temporal gap between the evolution of the Proto-Tethys Ocean and the Paleo-Tethys Ocean. The Triassic period marks a transitional phase in tectonic evolution, shifting into an intracontinental evolutionary stage. This study provides new geochronological evidence for the early developmental history of the West Kunlun orogenic belt. [ABSTRACT FROM AUTHOR]

Objective To investigate the efficacy of bio-targeted drug loaded nanoparticles for the diagnosis and treatment of breast cancer based on tumor hypoxia microenvironment. Methods Lipid nanoparticles loaded with perfluorohexane (PFH) and tirazamine (TPZ) were prepared by film hydration. Bifidobacteria were cultured and detected for basic characterizations. Then, the bacteria and nanoparticles were connected by electrostatic adsorption to prepare bio-targeted drug-loaded nanoparticles, and laser confocal microscopy and flow cytometry were used to detect the binding between them. Ultrasonic diagnostic imaging, MTT assay and flow cytometry were adopted to observe the in vitro imaging performance and killing effect on breast cancer cells after high-intensity focused ultrasound (HIFU) irradiation. Tissue homogenate was used to observe the targeting ability of bifidobacteria. In vivo fluorescence imaging was performed to monitor the targeting of nanoparticles. The 4T1 breast tumor-bearing mice were established and randomly divided into targeted group (n=3) and non-targeted group (n=3) to observe the ultrasound imaging performance of nanoparticles. The tumor-bearing mice were randomly divided into blank control group, PBS+HIFU group, nonoparticles+HIFU group, and nonoparticles+ bifidobacterium+HIFU group (n=3 for each group). The body weight and tumor volume were recorded during treatment process, HE staining was performed 14 d later to observe the morphological changes of the tumor mass. Results Bio-targeted drug loaded nanoparticles were successfully prepared. The nanoparticles had an average size of 218.93±6.56 nm and a zeta potential of 55.00±4.97 mV, and the bifidobacterium had a potential of -28.10±7.52 mV. The connection rate of the nanoparticles and bacterium was (99.04±0.40)%. The nanoparticles showed better ultrasound imaging after HIFU irradiation. The results of MTT assay and flow cytometry showed that the nanoparticles exerted better killing effect on breast cancer cells under hypoxic condition than under normoxia condition (P < 0.05). The results of tissue homogenate demonstrated that bifidobacteria showed good target ability. In vivo fluorescence imaging displayed that the nanoparticles were enriched around the tumor. In vivo ultrasound imaging was achieved in the targeted group after HIFU irradiation. Both the records of tumor volume and results of HE staining indicated that the nonoparticles+bifidobacterium+HIFU group got the best tumor inhibitory effect (P < 0.05). Conclusion The bio-targeted drug loaded nanoparticles can effectively diagnose and treat breast cancer based on hypoxia microenvironment. Our study provides a new thought for the integration of tumor diagnosis and treatment.

The Proterozoic oil in Gaosheng area of the Western Depression of Liaohe Basin has great potential and is an important exploration field. However, the study about control factors of Gaosheng reservoir needs to be improved. The source rocks are characterized by using geochemical techniques and the structural evolution history is restored by using 2D-Move software. The characteristics of reservoirs and caps are clarified, and the controlling factors of reservoir formation are summarized. The oil generation intensity of Es4 and Es3 is generally 5 χ 106-10 χ 106 t/km2, indicating that the oil source is sufficient. The sandstone reservoir has fracture and dissolution porosity, which provide storage space for oil accumulation. Faults and unconformities provide pathways for oil migration. The dense Fangshenpao and Mesozoic basalt is a good cap layer to preserve the reservoir, which effectively prevents the upward migration of oil. According to the comprehensive analysis of main controlling factors, the favorable exploration areas are pointed out. The research results are of great significance to guide the future oil and gas exploration in Liaohe Basin. [ABSTRACT FROM AUTHOR]