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[Objective] Population structure characteristics and survival status of natural Platycladus orientalis in the loess hilly region were determined in order to provide a scientific basis for high-quality and sustainable development of forest grassland in this area. [Methods] Characteristics were quantitatively analyzed by using a dynamic change index based on a static life table combined with spectral analysis on the time scale and time series simulation prediction to carry out a comprehensive survival analysis of this cypress species. [Results] ① The height, crown width, and diameter structure of the P. orientalis population indicated that young trees were abundant. ② The survival curve of the P. orientalis population was close to Deevey-Ⅱ type, and the population was sensitive to external interference. ③ Population dynamics were characterized by strong viability in the early stage, stable growth in the middle stage, and decline in viability in the later stage. Time series simulation and prediction analysis showed that the population of P. orientalis showed different degrees of increasing trend and strong growth recovery ability. [Conclusion] The natural population structure of P. orientalis in the loess hilly region was stable and growing, and the survival curve was close to that of Deevey-Ⅱ type.

The clumping index (CI) is a key structural parameter that quantifies the nonrandomness of the spatial distribution of vegetation canopy leaves. Investigating seasonal variations in the CI is crucial, especially for estimating the leaf area index (LAI) and studying global carbon and water cycles. However, accurate estimations of the seasonal CI have substantial challenges, e.g., from the need for accurate hot spot measurements, i.e., the typical feature of the bidirectional reflectance distribution function (BRDF) shape in the current CI algorithm framework. Therefore, deriving a phenologically simplified stable CI product from a high-frequency CI product (e.g., 8 days) to reduce the uncertainty of CI seasonality and simplify CI applications remains important. In this study, we applied the discrete Fourier transform and an improved dynamic threshold method to estimate the start of season (SOS) and end of season (EOS) from the CI time series and indicated that the CI exhibits significant seasonal variation characteristics that are generally consistent with the MODIS land surface phenology (LSP) product (MCD12Q2), although seasonal differences between them probably exist. Second, we divided the vegetation cycle into two phenological stages based on the MODIS LSP product, ignoring the differences mentioned above, i.e., the leaf-on season (LOS, from greenup to dormancy) and the leaf-off season (LFS, after dormancy and before greenup of the next vegetation cycle), and developed the phenologically simplified two-stage CI product for the years 2001–2020 using the MODIS 8-day CI product suite. Finally, we assessed the accuracy of this CI product (RMSE = 0.06, bias = 0.01) via 95 datasets from 14 field-measured sites globally. This study revealed that the CI exhibited an approximately inverse trend in terms of phenological variation compared with the NDVI. Globally, based on the phenologically simplified two-stage CI product, the CILOS is smaller than the CILFS across all land cover types. Compared with the LFS stage, the quality for this CI product is better in the LOS stage, where the QA is basically identified as 0 and 1, accounting for more than ~90% of the total quality flag, which is significantly higher than that in the LFS stage (~60%). This study provides relatively reliable CI datasets that capture the general trend of seasonal CI variations and simplify potential applications in modeling ecological, meteorological, and other surface processes at both global and regional scales. Therefore, this study provides both new perspectives and datasets for future research in relation to CI and other biophysical parameters, e.g., the LAI. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusion Esophageal squamous cell carcinoma (ESCC) is a global cancer related to the sixth largest cause of death. Circular RNAs (circRNAs) have affected the progress of ESCC during recent years, but the mechanism is not completely clear. So here we probed the effects of hsa_circ_0096710 (circ_0096710) in ESCC.Relative levels of circ_0096710, miR‐1294, and ADAM10 were quantified by the quantitative real‐time reverse transcription‐polymerase chain reaction in ESCC tissues. Western blot assessed ADAM10, PCNA, MMP2, VEGFA, and OCT4 protein levels. Cell proliferative capacity was assessed by cell counting and cell colony‐forming assays. Transwell assays assessed cell migration and invasion. Angiogenesis was detected by tube formation assays. Stemness of cancer cells was estimated by sphere formation assays. Dual‐luciferin reporter and RNA immunoprecipitation assays determined the targeting relationship between miR‐1294 and circ_0096710 or ADAM10.Relative levels of circ_0096710 and ADAM10 mRNA were upregulated in ESCC cells, yet miR‐1294 was downregulated. Circ_0096710 silencing repressed ESCC cell proliferation, migration, invasion, angiogenesis, and stem‐like properties. Moreover, circ_0096710 was an upstream target of miR‐1294, and miR‐1294 inhibition reversed the role of circ_0096710 downregulation in ESCC cells. Furthermore, ADAM10 was a downstream target of miR‐1294, and miR‐1294 overexpression suppressed ESCC cell proliferation, migration, invasion, angiogenesis, and stem‐like properties by targeting ADAM10. Meanwhile, circ_0096710 upgraded ADAM10 expression through sponging miR‐1294. Also, circ_0096710 downregulation restrained tumor growth in mouse models.Circ_0096710 upregulates ADAM10 via mediating miR‐1294 expression so as to accelerate the occurrence of ESCC, suggesting that circ_0096710 may be a potential therapeutic target for ESCC. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with a 5‐year survival rate of 7.2% in China. However, effective approaches for diagnosis of PDAC are limited. Tumor‐originating genomic and epigenomic aberration in circulating free DNA (cfDNA) have potential as liquid biopsy biomarkers for cancer diagnosis. Our study aims to assess the feasibility of cfDNA‐based liquid biopsy assay for PDAC diagnosis. In this study, we performed parallel genomic and epigenomic profiling of plasma cfDNA from Chinese PDAC patients and healthy individuals. Diagnostic models were built to distinguish PDAC patients from healthy individuals. Cancer‐specific changes in cfDNA methylation landscape were identified, and a diagnostic model based on six methylation markers achieved high sensitivity (88.7% for overall cases and 78.0% for stage I patients) and specificity (96.8%), outperforming the mutation‐based model significantly. Moreover, the combination of the methylation‐based model with carbohydrate antigen 19‐9 (CA19‐9) levels further improved the performance (sensitivity: 95.7% for overall cases and 95.5% for stage I patients; specificity: 93.3%). In conclusion, our findings suggest that both methylation‐based and integrated liquid biopsy assays hold promise as non‐invasive tools for detection of PDAC. [ABSTRACT FROM AUTHOR]

RAS proteins are necessary for cell survival, and their mutations are closely related to tumor formation and progression. Mutated RAS proteins were undruggable owing to their smooth surface decades ago. Since chemists found that covalently binding to mutated cysteine (G12 C) was a potential therapy for KRASG12C inhibition. Recently, AMG‐510 and MRTX‐849 were approved in 2021 and 2022 respectively for solid tumor treatment. In this paper, started with KRASG12C inhibitor ARS‐1620, we introduced different hydrophilic fragment on it and reached compound K09, which had the best KRASG12C inhibitory activity and antiproliferation activities. Compound K09 is regarded as a lead compound for further exploration. [ABSTRACT FROM AUTHOR]

Aiming at the problems of a large volume, slow processing speed, and difficult deployment in the edge terminal, this paper proposes a lightweight insulator detection algorithm based on an improved SSD. Firstly, the original feature extraction network VGG-16 is replaced by a lightweight Ghost Module network to initially achieve the lightweight model. A Feature Pyramid structure and Feature Pyramid Network (FPN+PAN) are integrated into the Neck part and a Simplified Spatial Pyramid Pooling Fast (SimSPPF) module is introduced to realize the integration of local features and global features. Secondly, multiple Spatial and Channel Squeeze-and-Excitation (scSE) attention mechanisms are introduced in the Neck part to make the model pay more attention to the channels containing important feature information. The original six detection heads are reduced to four to improve the inference speed of the network. In order to improve the recognition performance of occluded and overlapping targets, DIoU-NMS was used to replace the original non-maximum suppression (NMS). Furthermore, the channel pruning strategy is used to reduce the unimportant weight matrix of the model, and the knowledge distillation strategy is used to fine-adjust the network model after pruning, so as to ensure the detection accuracy. The experimental results show that the parameter number of the proposed model is reduced from 26.15 M to 0.61 M, the computational load is reduced from 118.95 G to 1.49 G, and the mAP is increased from 96.8% to 98%. Compared with other models, the proposed model not only guarantees the detection accuracy of the algorithm, but also greatly reduces the model volume, which provides support for the realization of visible light insulator target detection based on edge intelligence. [ABSTRACT FROM AUTHOR]

In order to explore the spatial distribution pattern and intra-specific correlation of Platycladus orientalis population in the Loess hilly region of Inner Mongolia, the natural Platycladus orientalis sparse forest in the typical Loess hilly region of Inner Mongolia was taken as the research object, and the spatial pattern of Platycladus orientalis population in different slope directions was analyzed using the point pattern combined with the complete spatial randomness, the heterogeneous Poisson model and the Poisson aggregation model of the single variable function, and the intra-specific grade was determined after the availability of the age class was determined by the fitting curve, a bivariate function was constructed to study the intra-specific correlation of Platycladus orientalis population. The results showed that the resources of regenerated seedlings were abundant, followed by young trees, and the number of mature trees was the least. The proportion of grade I was as high as 27.79%, grade II was 21.84%, and the cumulative proportion of grade III to grade V was 32.85%. The population distribution of each age class was pyramidal, and the population structure was stable, showing a steady growth trend.The quantity distribution of each age of 4~22 m, and the shady slope presents a small scale of 0~1 m aggregation distribution. The heterogeneous Poisson model showed that the slope direction had an impact on the aggregation degree of Platycladus orientalis population, and the Poisson aggregation model had an aggregation distribution within the range of 1~5 m, indicating that there was a certain relationship between species. There were 3 kinds of correlations in Platycladus orientalis species. The relationship between seedlings and adult trees was positive within 0~1 m of the scale of shady slope and semi-shady slope. The relationship between young trees and adult trees was completely in the confidence interval of sunny slope. The relationship between young trees and adult trees was negative at 6~7 and 3~4 m under the conditions of semi-shady slope and semi-sunny slope, respectively. The relationship between young trees and adult trees was negative at shady slope, semi-shady slope and semi-sunny slope, and the sunny slope was not negative relationship . To sum up, in addition to its own biological characteristics, the impact of microenvironment and intra-specific competition on the distribution of Platycladus orientalis population in the loess hilly area was also very important. Above results provided a basis for the planting and management of Platycladus orientalis and its habitat adaptability. [ABSTRACT FROM AUTHOR]