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PIEZO channels respond to piconewton-scale forces to mediate critical physiological and pathophysiological processes 1 – 5 . Detergent-solubilized PIEZO channels form bowl-shaped trimers comprising a central ion-conducting pore with an extracellular cap and three curved and non-planar blades with intracellular beams 6 – 10 , which may undergo force-induced deformation within lipid membranes 11 . However, the structures and mechanisms underlying the gating dynamics of PIEZO channels in lipid membranes remain unresolved. Here we determine the curved and flattened structures of PIEZO1 reconstituted in liposome vesicles, directly visualizing the substantial deformability of the PIEZO1–lipid bilayer system and an in-plane areal expansion of approximately 300 nm 2 in the flattened structure. The curved structure of PIEZO1 resembles the structure determined from detergent micelles, but has numerous bound phospholipids. By contrast, the flattened structure exhibits membrane tension-induced flattening of the blade, bending of the beam and detaching and rotating of the cap, which could collectively lead to gating of the ion-conducting pathway. On the basis of the measured in-plane membrane area expansion and stiffness constant of PIEZO1 (ref. 11 ), we calculate a half maximal activation tension of about 1.9 pN nm −1 , matching experimentally measured values. Thus, our studies provide a fundamental understanding of how the notable deformability and structural rearrangement of PIEZO1 achieve exquisite mechanosensitivity and unique curvature-based gating in lipid membranes. Cryo-electron microscopy structures of PIEZO1 in liposome vesicles in curved and flattened conformations demonstrate the high deformability underlying the high mechanosensitivity and ion selectivity of PIEZO channel gating.

In the current study, the effect of hydrogen atoms on the intergranular failure of α-iron is examined by a molecular dynamics (MD) simulation. The effect of hydrogen embrittlement on the grain boundary (GB) is investigated by diffusing hydrogen atoms into the grain boundaries using a bicrystal body-centered cubic (BCC) model and then deforming the model with a uniaxial tension. The Debye Waller factors are applied to illustrate the volume change of GBs, and the simulation results suggest that the trapped hydrogen atoms in GBs can therefore increase the excess volume of GBs, thus enhancing intergranular failure. When a constant displacement loading is applied to the bicrystal model, the increased strain energy can barely be released via dislocation emission when H is present. The hydrogen pinning effect occurs in the current dislocation slip system, 112. The hydrogen atoms facilitate cracking via a decrease of the free surface energy and enhance the phase transition via an increase in the local pressure. Hence, the failure mechanism is prone to intergranular failure so as to release excessive pressure and energy near GBs. This study provides a mechanistic framework of intergranular failure, and a theoretical model is then developed to predict the intergranular cracking rate.

Recent climate change has caused an increase in warming-driven erosion and sediment transport processes on the Tibetan Plateau (TP). Yet a lack of measurements hinders our understanding of basin-scale sediment dynamics and associated spatiotemporal changes. Here, using satellite-based estimates of suspended sediment, we reconstruct the quantitative history and patterns of erosion and sediment transport in major headwater basins from 1986 to 2021. Out of 13 warming-affected headwater regions, 63% of the rivers have experienced significant increases in sediment flux. Despite such intensified erosion, we find that 30% of the total suspended sediment flux has been temporarily deposited within rivers. Our findings reveal a pronounced spatiotemporal heterogeneity within and across basins. The recurrent fluctuations in erosion-deposition patterns within river channels not only result in the underestimation of erosion magnitude but also drive continuous transformations in valley morphology, thereby endangering local ecosystems, landscape stability, and infrastructure project safety. Climate change intensifies erosion and sediment transport in rivers of the Tibetan Plateau. Satellite data unveil unprecedented patterns of sediment deposition in rivers. Pronounced spatiotemporal heterogeneities within and across basins are found.

Introduction Poor electrocardiogram (ECG) interpretation skills among medical students are a widespread issue globally. However, few studies have systematically investigated the practical challenges students face during the learning process. This study aimed to identify the specific obstacles encountered by medical students in learning ECG interpretation and to propose evidence-based recommendations for curricular improvement. Methods A questionnaire survey was conducted among interns and other relevant student groups who were about to begin or had completed their ECG internship at the Second Affiliated Hospital of Anhui Medical University. A total of 309 valid, voluntarily submitted responses were collected and analyzed using descriptive statistics, difference analysis, and correlation analysis. Results Most students agreed with statements such as \"Even with solid theoretical knowledge, interpreting ECGs in practice is challenging\", \"Practical ECG waveforms are complex and variable, making analysis difficult\", and \"The abstract nature of ECG waveforms increases the threshold for learning electrocardiography\". These perceptions did not differ significantly by gender, identity, level of education, or undergraduate field of study ( P  > 0.05). Correlation analysis revealed a significant association between \"the absence of textual labels in ECG diagrams\" and \"the abstract nature of ECG waveforms may increase the difficulty of learning ECG\" ( r  = 0.728), as well as between \"Even with solid theoretical knowledge, ECG interpretation remains challenging\" and \"ECG diagrams are complex and difficult to analyze\" ( r  = 0.715). Moreover, internship experience significantly reduced medical students' perceived difficulty in learning ECGs (3.99 ± 0.70 vs. 3.75 ± 0.71, P  = 0.002). Conclusions The primary barrier in ECG interpretation is the abstract and complex nature of waveforms. Teaching should focus on strategies to address this challenge. The proposed translation method offers a novel approach to improve learning.

The study of the pedogenic process in response to natural evolution, gradual anthropogenic shifts and engineering upheavals is of great significance for understanding, utilizing and transforming nature in the future. Although scholars have considered anthropic activities to be an important factor affecting pedogenesis, research on how and how much anthropic activities influence the soil-forming process is scant. This paper was conducted to analyse pedogenic characteristics dominated by anthropic activities. In this study, the parent materials and soils undergoing natural evolution (NE), tillage perturbation (TP) and engineering perturbation (EP) were selected as research objects. The genetic characteristics of soils undergoing NE, TP and EP are investigated mainly from three aspects: soil profile macromorphological characteristics, soil physical and chemical properties and chemical weathering characteristics. The results indicated that the influence of anthropic activities (TP and EP) on the process of pedogenesis is complicated. First, compared with NE, TP decreases the thickness of topsoil from 22.2 to 21.2 cm, while EP increases the thickness of topsoil from 22.2 to 23.2 cm, and EP causes the soil to have a high profile development index. Second, compared with TP, EP can improve bulk density (BD), soil organic carbon (SOC), total nitrogen (TN) and cation exchange capacity (CEC), Finally, the chemical weathering intensity differed among NE, TP and EP and followed the order of TP > NE > EP. Therefore, in the future, the genetic characteristics of soils dominated by anthropic activities should be considered. This will help us systematically understand the genesis and evolutionary characteristics of soil and lay a foundation for further perfecting the diagnostic horizon and diagnostic characteristics of the Soil Taxonomy and World Reference Base.

The Qinghai‐Tibetan Plateau (QTP) has undergone significant warming, wetting, and greening (WWG) over decades, alongside substantial alterations in hydrological regimes. These changes present great challenges for safeguarding water resources and ecosystems downstream. However, the lack of field observation and systematic research has obscured our understanding of how hydrological processes respond to the combined influences of climate‐permafrost‐vegetation. This study focuses on the source regions of the Yangtze River, one of the highest permafrost‐covered basins on the QTP, and employs a process‐based hydrological model to quantify the effects of WWG on hydrological processes. We show that the increasing precipitation dominates subsurface runoff changes while rising temperature primarily affects surface runoff changes by reducing the frozen duration (−52 days/century) and thickening the active layer (+2.4 cm/year). Greening vegetation primarily affects transpiration and interception evaporation. Warming, wetting, and greening will cause a transition in runoff dynamics from surface runoff dominance to subsurface runoff dominance in permafrost basins, and reduce the risk of both flooding and water shortage indicated by the decreased maximum low flow duration and maximum high flow duration of 11.0 and 5.0 days/year, respectively. Moreover, cold permafrost regions exhibit a greater propensity for generating runoff, as indicated by a higher annual increase in runoff coefficient (0.005/year) and total runoff (4.81 mm/year), compared to warm permafrost regions (with increase of 0.001/year and 1.20 mm/year, respectively). These findings enhance the understanding of hydrological changes due to WWG and provide insights for water resources management in permafrost regions under climate change. Plain Language Summary The Qinghai‐Tibetan Plateau (QTP) has been experiencing significant changes in its climate, becoming warmer, wetter, and greener over the years. These changes have led to major shifts in water flow and availability, posing challenges for managing water resources downstream. However, our understanding of how these changes in climate, permafrost, and vegetation interact and affect hydrological processes has been limited due to a lack of field data and systematic research. This study uses a hydrological model to better understand these effects. It shows that increasing precipitation mainly impacts subsurface runoff and rising air temperatures affect surface runoff by reducing the frozen period and thickening the active layer. Greening vegetation primarily affects transpiration and interception evaporation. Overall, the WWG will shift runoff patterns from surface to subsurface dominance in permafrost areas, reducing the risk of both floods and water shortages. Additionally, colder permafrost regions are more likely to generate runoff compared to warmer permafrost regions. These insights help improve our understanding of how water processes are changing due to the combined effects of a warmer, wetter, and greener climate on the QTP, and they provide valuable information for managing water resources in these regions as the climate continues to change. Key Points Precipitation dominates subsurface runoff changes in permafrost regions, and air temperature affects surface runoff via freeze‐thaw processes Runoff process in permafrost regions will shift from surface runoff to subsurface runoff dominance due to warming, wetting, and greening (WWG) Lower evapotranspiration, thinner active layer, and shorter thaw duration led to higher runoff coefficients and runoff increase rates in cold permafrost (CP) regions

Topography is a critical factor that determines the characteristics of regional soil formation. Small-scale topographic changes are referred to microtopographies. In hilly mountainous regions, the redistribution of water and soil materials caused by microtopography is the main factor affecting the spatial heterogeneity of soil and the utilization of land resources. In this study, the influence of microtopography on pedogenesis was investigated using soil samples formed from mudstones with lacustrine facies deposition in the middle of the Sichuan Basin. Soil profiles were sampled along the slopes at the summit, shoulder, backslope, footslope, and toeslope positions. The morphological, physicochemical, and geochemical attributes of profiles were analyzed. The results showed that from the summit to the toeslope, soil thickness increased significantly and profile configuration changed from A–C to A–B–C. The total contents of Ca and Na decreased at the summit, backslope, and footslope, while the total contents of Al, Fe and Mg showed an opposite trend. On the summit and shoulder of the hillslope, weathered materials were transported away by gravity and surface erosion, exposing new rocks. As a result, soil development in these areas was relatively weak. In flat areas such as the footslope and toeslope with sufficient water conditions, the addition of weathered components and the prolonged contact between water, soil, and sediment led to further chemical weathering, resulting in highly developed characteristics. Microtopography may influence physicochemical properties, chemical weathering, and redistribution of water and materials, causing variations in pedogenic characteristics at different slope positions.

Stream gauging stations provide critical streamflow measurements for hydrological applications; however, they may not accurately capture total catchment discharge due to unmonitored regional groundwater flow. Here, we evaluate the effectiveness of streamflow data from gauging stations worldwide to represent total catchment discharge through a modified hydrological model that includes baseflow signatures to constrain groundwater flow processes. We find that approximately 70% of gauging stations present biased estimations of total catchment discharge (bias >10%). This result implies that hydrology‐related processes may not be fully understood, and misleading conclusions may be drawn owing to the low streamflow measurement effectiveness. By influencing subsurface hydrological processes, catchment factors, including catchment area, topography, climate, and geological features, are linked to the effectiveness of streamflow measurements. Our findings highlight the importance of accurate streamflow measurement effectiveness for obtaining a reliable understanding of catchment hydrological processes to support sustainable water resource management. Plain Language Summary The outflow of water from catchments plays a critical role in supporting downstream ecosystems and human society. This catchment outflow includes surface and subsurface discharge. However, a portion of the subsurface discharge may not directly flow into river networks and thus remains unaccounted for in streamflow records at gauging stations. The extent to which these unmonitored subsurface flows exist across catchments and their contribution to the total catchment discharge remains unknown. To address this knowledge gap, we have developed a novel method that simulates the movement of both surface and subsurface flows, enabling us to evaluate the representativeness of streamflow records in capturing the total catchment discharge. Our findings indicate that approximately 70% of gauging stations worldwide inadequately capture the total catchment discharge (bias >10%). This observation highlights the importance of unmonitored subsurface discharge as a significant component of catchment water yield. Such insights enhance our understanding of catchment hydrological processes, supporting the development of sustainable water resource management strategies. Key Points A modified hydrological model was developed by including baseflow signatures to constrain groundwater flow processes Approximately 70% of gauging stations presented biased estimations of total catchment discharge The catchment hydrological response based on gauging station measurements is highly likely to be overestimated or underestimated

Background As air temperatures increase globally, more and more plants are exposed to heat-stress conditions. Although many studies have explored regulation networks in plants with the aim of improving their heat-stress tolerance, only few have revealed them in trees. Here, individuals of Populus qiongdaoensis seedlings, which grows naturally in tropical areas, exposed to heat at 40 °C and the non-coding regulation networks were explored using the PacBio RSII and the Illumina sequencing platform. Results In total, we obtained 88,161 full-length transcripts representing 39,343 genes using 5,498,988 long reads and 350,026,252 clean reads, and also 216 microRNAs (miRNAs) via 95,794,107 reads. We then identified 928 putative long non-coding RNAs (lncRNAs), consisting of 828 sense lncRNAs (89.22%), 34 long intergenic non-coding RNAs (3.66%), 16 antisense (1.72%), and 50 sense intronic lncRNAs (5.39%). Under the dual criteria of |log 2 fold-change| ≥ 1 and P -value < 0.05, 1690 genes, 25 lncRNAs, and 15 miRNAs were found differentially expressed under the heat stress treatment. Furthermore, 563 and 595 mRNAs were detected as target genes of 14 differently expressed miRNAs and 26 differentially expressed lncRNAs. Functional annotation analysis of these target genes demonstrated they were related to cell membrane stability, plant hormone signal transduction, antioxidation, and aldarate metabolism. Lastly, we uncovered a key interaction network of lncRNAs, miRNAs and mRNAs that consisted of miR1444d, miR482a.1, miR530a, lncHSP18.2, HSP18.1 , and HSP18.2 . Expression level analysis showed that miRNAs in the network were up-regulated, while mRNAs and lncRNA were down-regulated, and also found that lncHSP18.2 may cis -regulate HSP18.2 . Conclusions Functional enrichment analysis of target genes of miRNAs and lncRNAs indicated that miRNAs and lncRNAs play an important role in the response to heat stress P. qiongdaoensis . Lastly, by investigating the miRNA–lncRNA–mRNA network of this species, we revealed that miRNAs may negatively regulate both lncRNAs and mRNAs in tree responses to heat stress, and found that lncHSP18.2 may cis -regulate HSP18.2 .

Aims Diabetes mellitus (DM) is closely associated with Alzheimer's disease (AD), and is considered an accelerator of AD. Our previous study has confirmed that the Calpain inhibitor Calpeptin may alleviate AD‐like complications of diabetes mellitus. This work further investigated its underlying mechanism. Materials and Methods Diabetes mellitus rat model was constructed by a high‐fat and high‐sugar diet combined with streptozotocin, followed by the administration of Calpeptin. Moreover, rats were micro‐injected with LV‐TXNIP‐OE/vector into the CA1 region of the hippocampus one day before streptozotocin injection. The Morris water maze test assessed the spatial learning and memory ability of rats. Immunohistochemistry and western blotting detected the expression of the pericyte marker PDGFRβ, tight junction proteins occludin and ZO‐1, calpain‐1, calpain‐2, APP, Aβ, Aβ‐related, and TXNIP/NLRP3 inflammasome‐related proteins. Immunofluorescence staining examined the blood vessel density and neurons in the hippocampus. Evans blue extravasation and fluorescence detected the permeability of the blood–brain barrier (BBB) in rats. Additionally, the oxidative stress markers and inflammatory‐related factors were assessed by enzyme‐linked immunosorbent assay. Results Calpeptin effectively reduced the expression of Calpain‐2 and TXNIP/NLRP3 inflammasome‐related proteins, improved the decreased pericyte marker (PDGFR‐β) and cognitive impairment in hippocampus of DM rats. The neuronal loss, microvessel density, permeability of BBB, Aβ accumulation, inflammation, and oxidative stress injury in the hippocampus of DM rats were also partly rescued by calpeptin treatment. The influence conferred by calpeptin treatment was reversed by TXNIP overexpression. Conclusions These data demonstrated that calpeptin treatment alleviated AD‐like symptoms in DM rats through regulating TXNIP/NLRP3 inflammasome. Thus, calpeptin may be a potential drug to treat AD‐like complications of diabetes mellitus. These data demonstrated that calpeptin treatment alleviated Alzheimer's disease‐like symptoms in diabetes mellitus rats through regulating TXNIP/NLRP3 inflammasome. Thus, calpeptin may be a potential drug to treat AD‐like complications of diabetes mellitus.