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Regional tectonic uplift information is recorded by knickpoints distributed in multiple rivers. The changing base level (mainstream) caused by tectonic uplift also controls karst development. Groundwater should drain as springs near the base level due to karstification usually occurring near the base level, but some drains were higher than the present river in the canyon. The assumption is proposed that the spring is more elevated than the current river formed at the older intermittent stage in uplift processes and that knickpoints at the elevation can correspond to the springs. A typical basin south of Daba Mountain is selected to identify the assumption. Three knickpoints with 11 karst landforms suggest that knickpoints can indicate the karst development elevation in the basin. This method is promoted to 29 basins around Daba Mountain which are separated into DTB (North Daba Mountain Pre-Land Thrust Fault Belt) representing north part and DFB (South Daba Mountain Pre-Land Fold Belt) representing south part to verify the effectiveness of the assumption. The result discovers that the knickpoints and karst landforms have a similar high-frequency elevation interval in DFB and little variance in DTB. The reason may be that DFB has better karstification conditions, including precipitation and carbonate rock cover area, than DTB. Knickpoints is an effective indicator for karst development in area that has sufficient karstification condition like DFB. This study may provide a new perspective on the relationship between karst development and tectonic uplift and a method to find the karst groundwater drain elevation. [ABSTRACT FROM AUTHOR]

Brain-derived extracellular vesicles participate in interorgan communication after traumatic brain injury by transporting pathogens to initiate secondary injury. Inflammasome-related proteins encapsulated in brain-derived extracellular vesicles can cross the blood‒brain barrier to reach distal tissues. These proteins initiate inflammatory dysfunction, such as neurogenic heterotopic ossification. This recurrent condition is highly debilitating to patients because of its relatively unknown pathogenesis and the lack of effective prophylactic intervention strategies. Accordingly, a rat model of neurogenic heterotopic ossification induced by combined traumatic brain injury and achillotenotomy was developed to address these two issues. Histological examination of the injured tendon revealed the coexistence of ectopic calcification and fibroblast pyroptosis. The relationships among brain-derived extracellular vesicles, fibroblast pyroptosis and ectopic calcification were further investigated in vitro and in vivo. Intravenous injection of the pyroptosis inhibitor Ac-YVAD-cmk reversed the development of neurogenic heterotopic ossification in vivo. The present work highlights the role of brain-derived extracellular vesicles in the pathogenesis of neurogenic heterotopic ossification and offers a potential strategy for preventing neurogenic heterotopic ossification after traumatic brain injury. [ABSTRACT FROM AUTHOR]

The synergistic effect that arises from blending functional agents with ordered fiber orientated structures is a noteworthy strategy to improve the mechanical properties, flexibility and waterproof performance of polylactic acid microfibrous fabrics. A promising polylactic acid/polyethylene glycol@erucamide (PLA/PEG@Era) microfibrous fabric with an ordered fiber orientation was successfully prepared by blending Era with PLA, followed by composite preparation processes of melt blowing and stretching. The results of the study revealed that the blended PLA/PEG@Era polymer with an Era mass ratio of 1.5% exhibited a higher relative degree of crystallinity of about 18.64% in comparison to the PLA/PEG polymer with a crystallinity degree of 2.24%. Moreover, the prepared fabrics exhibited a pleasant microfibrous nonwoven structure with an ordered, regular and a compensating fiber distribution, obtained by facile tailing of the stretching ratio. Also, the samples showed a high tensile breaking strength of 41.1 N with a good vapor permeability, ranging from 2537.2 g/(m2·day) to 2136.9 g/(m2·day), in addition to its excellent waterproof performance and softness. The study provides sufficient evidence that the developed PLA/PEG@Era microfibrous fabrics are extremely suitable candidates for packaging and outdoor clothing applications. [ABSTRACT FROM AUTHOR]

EN1 encodes a homeodomain-containing transcription factor and is a determinant of bone density and fracture. Previous powerful genome-wide association studies (GWASs) have identified multiple single-nucleotide polymorphisms (SNPs) near EN1 at 2q14.2 locus for osteoporosis, but the causal SNPs and functional mechanisms underlying these associations are poorly understood. The target genes regulated by the transcription factor EN1 are also unclear. In this study, we identified rs188303909, a functional CpG-SNP, as a causal SNP for osteoporosis at 2q14.2 through the integration of functional and epigenomic analyses. Functional experiments demonstrated that unmethylated rs188303909 acted as a strong allele-specific distal enhancer to regulate EN1 expression by modifying the binding of transcription factor E2F6, but rs188303909 methylation attenuated the active effect of E2F6 on EN1 expression. Importantly, transcription factor EN1 could differentially bind osteoporosis GWAS lead SNPs rs4869739-T and rs4355801-G to upregulate CCDC170 and COLEC10 expression, thus promoting bone formation. Our study provided a mechanistic insight into expression regulation of the osteoporosis susceptibility gene EN1, which could be a potential therapeutic target for osteoporosis precision medicine. Key messages: CpG-SNP rs188303909 is a causal SNP at the osteoporosis susceptibility locus 2q14.2. Rs188303909 distally regulates EN1 expression by modulating DNA methylation and E2F6 binding. EN1 upregulates CCDC170 and COLEC10 expression through osteoporosis GWAS lead SNPs rs4869739 and rs4355801. [ABSTRACT FROM AUTHOR]

The silent information regulator T1 (SIRT1) is linked to longevity and is a crucial mediator of osteoblast function. We investigated the direct role of Sirt1 during bone modeling and remodeling stages in vivo using Tamoxifen-inducible osteoblast-specific Sirt1 conditional knockout (cKO) mice. cKO mice exhibited lower trabecular and cortical bone mass in the distal femur. These phenotypes were coupled with lower bone formation and bone resorption. Metabolomics analysis revealed that the metabolites involved in glycolysis were significantly decreased in cKO mice. Further analysis of the quantitative acetylome revealed 11 proteins with upregulated acetylation levels in both the femur and calvaria of cKO mice. Cross-analysis identified four proteins with the same upregulated lysine acetylation site in both the femur and calvaria of cKO mice. A combined analysis of the metabolome and acetylome, as well as immunoprecipitation, gene knockout, and site-mutation experiments, revealed that Sirt1 deletion inhibited glycolysis by directly binding to and increasing the acetylation level of Glutamine oxaloacetic transaminase 1 (GOT1). In conclusion, our study suggested that Sirt1 played a crucial role in regulating osteoblast metabolism to maintain bone homeostasis through its deacetylase activity on GOT1. These findings provided a novel insight into the potential targeting of osteoblast metabolism for the treatment of bone-related diseases. [ABSTRACT FROM AUTHOR]

Detection of subsurface hydrodynamic anomalies plays a significant role in groundwater resource management and environmental monitoring. In this paper, based on data from the groundwater level, atmospheric pressure, and precipitation in the Chengdu area of China, a method for detecting outliers considering the factors affecting groundwater levels is proposed. By analyzing the factors affecting groundwater levels in the monitoring site and eliminating them, simplified groundwater data is obtained. Applying sl-Pauta (self-learning-based Pauta), iForest (Isolated Forest), OCSVM (One-Class SVM), and KNN to synthetic data with known outliers, testing and evaluating the effectiveness of 4 technologies. Finally, the four methods are applied to the detection of outliers in simplified groundwater levels. The results show that in the detection of outliers in synthesized data, the OCSVM method has the best detection performance, with a precision rate of 88.89%, a recall rate of 91.43%, an F1 score of 90.14%, and an AUC value of 95.66%. In the detection of outliers in simplified groundwater levels, a qualitative analysis of the displacement data within the field of view indicates that the outlier detection performance of iForest and OCSVM is better than that of KNN. The proposed method for considering the factors affecting groundwater levels can improve the efficiency and accuracy of detecting outliers in groundwater level data. [ABSTRACT FROM AUTHOR]

In this work, α-SiC ceramics with aluminum or yttria sintering additives ranging from 1.0 to 4.0 wt pct were prepared by hot pressing, and the effect of sintering additives on the microstructure and mechanical properties of SiC ceramics was investigated. Specimens with Al additive exhibited fully dense microstructure with relative density > 99.4 pct. However, the relative density of specimens with Y2O3 decreases constantly from 99.5 to 95.7 pct as Y2O3 content increases, which is possibly due to the formation of gaseous phase and evaporation of volatile compounds resulting from the chemical reaction between SiC matrix and Y2O3 additive. X-ray diffraction (XRD) and Raman spectra results showed that Al addition leads to the transformation from 6H to 4H polytypes, and the transformation degree increases as increasing the Al content, while no obvious polytype transformation is observed for specimens with Y2O3 additive. Scanning electron microscopy (SEM) observations revealed that specimens with Y2O3 are composed of equiaxed grains with average size about 1.0 μm, whereas the specimens with Al additive exhibit larger grain size with partly elongated grain structure. Additionally, it is found that the grain growth of specimens with Al addition is accompanied by the polytype transformation. Further analysis revealed that, for specimens with Al additive, enhanced grain size and formation of elongated of SiC grains lead to an improvement in fracture toughness from 5.7 to 7.1 MPa m1/2 but a slight decline in flexural strength from 706 to 632 MPa. The crack deflection and bridging as well as undesirable stress effects related to the large elongated grains are responsible for the variation in mechanical properties. In the case of SiC sintered with Y2O3, there are obvious declines in flexural strength and fracture toughness from 714 to 492 MPa and from 5.9 to 3.4 MPa m1/2, respectively, which are mainly attributed to the increased porosity. The impact of Al and Y2O3 on the microstructure and mechanical properties of SiC ceramics was discussed. [ABSTRACT FROM AUTHOR]

The multi-view of an object can be used for 3D reconstruction. The method proposed in this paper generates the left and the top view of a target car through deep learning. The input of the method is only a front view of a 3D car and it isn't necessary for the depth of the 3D car. Firstly, a rough orthographic views of the 3D car is gotten from an information constraint network which is constructed by considering the structural relation between one view and the other two views. And then the rough orthographic views is transformed into large-pixel block rough view through the nearest interpolation, at the same time, the large-pixel blocks are also migrated to improve the quality of the rough orthographic views. Finally, the generative adversarial network with perception loss is used to enhance the large-pixel block view. In addition, the three views generated by the network can be used to synthesize a 3D point cloud shell. [ABSTRACT FROM AUTHOR]