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This study presents an integrated approach using organic geochemistry and incident-light organic petrographic microscopy techniques to characterize the kerogen type, hydrocarbon potential, thermal maturity, and effective depositional environment of the Eocene Liushagang Formation intervals in the western Huangtong Sag, eastern Bailian Sag, central Huachang Sub-uplift, and Southern Slope Zone area in the Fushan Depression, Beibuwan Basin. The results show that the hydrocarbon potential of these organic-rich lacustrine shale areas is mainly dependent on the depositional environment and the present-day burial depth of sediments. Oscillations and transitions between (i) rocks with dominant allochthonous organic matter (including primary/reworked vitrinite and inertinite macerals and terrestrial debris particles) representing a large influence of continental sediments (e.g., source supply direction) and (ii) rocks with dominant autochthonous organic matter (e.g., alginite) indicate a distal and stable lacustrine basin depositional environment. The source rock thickness ranges from 40.1 to 387.4 m. The average TOC of the Liushagang Formation in the Fushan Sag is between 0.98% and 2.00%, with the highest organic matter abundance being in the first and second sections of the Liushagang Formation, presenting as high-quality source rocks. The organic matter is predominantly Type II1 and Type II2. The highest vitrinite reflectance (1.14%) is in the Huangtong and Bailian Sags. The source rocks of the second section of the Liushagang Formation are primary hydrocarbon generators, contributing 55.11% of the total generation. Hydrocarbon sequestration peaks at %Ro 0.80%, with a maximum efficiency of 97.7%. The cumulative hydrocarbon generation of the Liushagang Formation is 134.10 × 108 tons, with 50.52 × 108 tons having been expelled and 83.58 × 108 tons remaining. E2L2X and E2L2S have maximum hydrocarbon displacement intensities of 184.22 × 104 t/km² and 45.39 × 104 t/km², respectively, with cumulative displacements of 52.99 × 108 tons and 15.58 × 108 tons. The oil and gas accumulation system is highly prospective, showing significant exploration potential. [ABSTRACT FROM AUTHOR]

Defining the structure and evolution of multi-trend faults is critical for analyzing the accumulation of hydrocarbons in buried hills. Based on high-resolution seismic and drilling data, the structural characteristics and evolutionary mechanism of multi-trend faults were investigated in detail through the structural analysis theory and quantitative calculations of fault activity, allowing us to determine the implication that fault evolution exerts on hydrocarbon accumulation in the BZ19-6 buried hill. There are four kinds of strike faults developed on the buried hill: SN-, NNE-, NE–ENE-, and nearly EW-trending, which experienced the Mesozoic Indosinian, Yanshan, and Cenozoic Himalayan tectonic movements. During the Indosinian, the BZ19-6 was in a SN-oriented compressional setting, with active faults composed of SN-trending strike-slip faults (west branch of the Tanlu fault zone) and near EW-trending thrust faults (Zhang-peng fault zone). During the Yanshanian, the NNE-trending normal faults were formed under the WNW–ESE tensile stress field. Since the Himalayan period, the BZ19-6 buried hill has evolved into the rifting stage. In rifting stage Ⅰ, all of the multi-trend pre-existing faults were reactivated, and the EW-trending thrust faults became normal faults due to negative inversion. In rifting stage II, a large number of NE–ENE-trending normal faults were newly formed in the NW–SE-oriented extensional setting, which made the structure pattern more complicated. In rifting stage III, the buried hill entered the post-rift stage, with only part of the NNE- and NE–ENE-trending faults continuously active. Multi-trend faults are the result of the combination of various multi-phase stress fields and pre-existing structures, which have great influence on the formation of tectonic fractures and then control the distribution of high-quality reservoirs in buried hills. The fractures controlled by the NNE- and EW-trending faults have higher density and scale, and fractures controlled by NE–ENE trending faults have stronger connectivity and effectiveness. The superposition of multi-trend faults is the favorable distribution of high-quality reservoirs and the favorable accumulation area of hydrocarbon. [ABSTRACT FROM AUTHOR]

Background: Siamese network (SN) using longitudinal DCE‐MRI for pathologic complete response (pCR) identification lack a unified approach to phases selection. Purpose: To identify pCR in early‐stage NAC, using SN with longitudinal DCE‐MRI and introducing IPS for phases selection. Study Type: Multicenter, longitudinal. Population: Center A: 162 female patients (50.63 ± 8.41 years) divided 7:3 into training and internal validation cohorts. Center B: 61 female patients (50.08 ± 7.82 years) were used as an external validation cohort. Field Strength/Sequence: Center A: single vendor 3.0 T with a compressed‐sensing volume interpolated breath‐hold examination sequence. Center B: single vendor 1.5 T with volume interpolated breath‐hold examination sequence. Assessment: Patients underwent DCE‐MRI before and after two NAC cycles, with tumor regions of interest (ROI) manually delineated. Histopathology was the reference for pCR identification. Models developed included a clinical one, four SN models based on IPS‐selected phases, and integrated models combining clinical and SN features. Statistical Tests: Model performance was evaluated using the area under the receiver operating characteristic curve (AUC). The DeLong test was used to compare AUCs. Net reclassification improvement and integrated discrimination improvement (IDI) tests were employed for performance comparison. P < 0.05 was considered significant. Results: In internal and external validation cohorts, the clinical model showed AUCs of 0.760 and 0.718. SN and integrated models, with increasing phases via IPS, achieved AUCs ranging from 0.813 to 0.951 and 0.818 to 0.922. Notably, SN‐3 and integrated‐3 and integrated‐4 outperformed the clinical model. However, input phases beyond 20% did not significantly enhance performance (IDI test: SN‐4 vs. SN‐3, P = 0.314 and 0.630; integrated‐4 vs. integrated‐3, P = 0.785 and 0.709). Data Conclusion: The longitudinal multiphase DCE‐MRI based on the SN demonstrates promise for identifying pCR in breast cancer. Evidence Level: 1 Technical Efficacy: Stage 4 [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 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]

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]