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The uplift of the Tibetan Plateau is one of the most important geological events in the Cenozoic era, which has had a far-reaching impact on climate change in neighboring regions and even the world. Scholars have already considered that the uplift of this period has a good coupling with the warm and cold climate changes. The Beilianchi section is west of Liupan Mountain, the back edge of the arcuate tectonic belt on the northeast margin of the Tibetan Plateau. The Paleocene Qingshuiying Formation is mainly a set of shallow lacustrine deposits dominated by purple-red mudstone with thin gypsum layers containing rich paleoenvironmental and paleoclimatic information. The article systematically studied the palynological assemblage of the Beilianchi section and identified 60 genera and 65 species of sporopollen types as well as several undetermined species. The assemblage is characterized by dominant angiosperm pollen grains and rare gymnosperm pollen and fern spores. Based on the existing research results of regional sporopollen, the geologic age of the Qingshuiying Formation is believed to be the middle-late Oligocene–early Miocene. The sporopollen flora is dominated by deciduous broad-leaved plants such as Betulaceae, Juglandaceae, and Ulmaceae, and pollens from a few but diverse tropical-subtropical plants also occur in the assemblage. In contrast, the pollen content of typical arid shrubs and herbaceous plants is small, generally reflecting the warm-temperate zone's milder and wetter paleoenvironmental and paleoclimatic background. The absence of pollen from cold-tolerant mountain conifers in the palynological assemblage indicates that the regional climatic environment had not yet changed from warm to cold during this period and that the uplift and expansion of the Tibetan Plateau to the northeast had not yet affected the Liupanshan area. The results of this study provide new evidence to constrain the depositional age of the Qingshuiying Formation on the northeastern margin of the Tibetan Plateau and the impact of the uplift process of the Tibetan Plateau on the paleoecology and paleoclimate of the region.

The article explores the evolution of regional spatial differences and has important practical significance for promoting the coordinated development of regional tourism. The article analyzes the characteristics of the spatial evolution of the economic tourism pattern from 2010 to 2020. The study found that the development of the regional tourism economy is on the rise, and the development is not balanced. The spatial self-organization of economic development is getting stronger and stronger, and the spatial economic distribution is different. Then this article analyzes the main factors that cause this spatial distribution and proposes corresponding solutions. This provides a theoretical basis for reducing the gap in the tourism economy between regions and promoting the coordinated development of the regional tourism economy.

Photodynamic therapy (PDT) is a highly promising modality against cancer, but its efficacy is severely limited by the low oxygen content in solid tumors. In this study, a smart photosensitive NiPS3 nanosheet was developed to solve the problem of low oxygen to allow PDT to be performed against tumors. The photosensitized ROS generation mechanism of NiPS3 is the photon-generated electron-hole pathway, which can generate O2 ·− and ·OH at the conduction band and valance band, respectively. More crucial is that ·OH generation doesn’t need O2, and the O2 ·− can also work in a low O2 environment, and depleting oxygen in tumor cells. Modified with triphenylphosphine (TPP) and based on density functional theory (DFT) calculations and experimental data, the NiPS3@TPP nano-system underwent targeted action toward mitochondria. In vitro experiments demonstrated that the reactive oxygen species (ROS) produced by NiPS3@TPP altered mitochondrial membrane permeability, which not only prolonged the PDT effect but also resulted in mitochondria apoptosis pathways inducing an apoptosis cascade. In vivo experiments demonstrated the targeting capability with low toxicity of the NiPS3@TPP nano-system. Tumor targeting at the tested dose indicated that it represented a promising biocompatible photosensitizer for in vivo biomedical applications.

Islet β cells from newborn mammals exhibit high basal insulin secretion and poor glucose-stimulated insulin secretion (GSIS). Here we show that β cells of newborns secrete more insulin than adults in response to similar intracellular Ca2+ concentrations, suggesting differences in the Ca2+ sensitivity of insulin secretion. Synaptotagmin 4 (Syt4), a non-Ca2+ binding paralog of the β cell Ca2+ sensor Syt7, increased by ∼8-fold during β cell maturation. Syt4 ablation increased basal insulin secretion and compromised GSIS. Precocious Syt4 expression repressed basal insulin secretion but also impaired islet morphogenesis and GSIS. Syt4 was localized on insulin granules and Syt4 levels inversely related to the number of readily releasable vesicles. Thus, transcriptional regulation of Syt4 affects insulin secretion; Syt4 expression is regulated in part by Myt transcription factors, which repress Syt4 transcription. Finally, human SYT4 regulated GSIS in EndoC-βH1 cells, a human β cell line. These findings reveal the role that altered Ca2+ sensing plays in regulating β cell maturation.