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A series of novel quinoline-O-carbamate derivatives was rationally designed for treating Alzheimer's disease (AD) by multi-target-directed ligands (MTDLs) strategy. The target compounds were synthesised and evaluated by AChE/BuChE inhibition and anti-inflammatory property. The in vitro activities showed that compound 3f was a reversible dual eeAChE/eqBuChE inhibitor with IC50 values of 1.3 µM and 0.81 µM, respectively. Moreover, compound 3f displayed good anti-inflammatory property by decreasing the production of IL-6, IL-1β and NO. In addition, compound 3f presented significant neuroprotective effect on Aβ25-35-induced PC12 cell injury. Furthermore, compound 3f presented good stabilities in artificial gastrointestinal fluids, liver microsomes in vitro and plasma. Furthermore, compound 3f could improve AlCl3-induced zebrafish AD model by increasing the level of ACh. Therefore, compound 3f was a promising multifunctional agent for the treatment of AD. [ABSTRACT FROM AUTHOR]

Introduction:  Since the onset of coronavirus disease 2019 (COVID-19), stay-at-home orders and fear caused by the pandemic have had a significant effect on the timing and outcomes of testicular torsion. However, the evidence was limited since the study results were inconsistent. This study aims to examine the hospitalization rates, timing, and outcomes of testicular torsion in children before and during the pandemic.Materials and Methods:  Using PubMed, Embase, and Google Scholar databases, we conducted a systematic search and meta-analysis of studies reporting the timing and outcomes of children admitted with testicular torsion before and during the COVID-19 pandemic. Subgroup analyses were conducted to explore possible sources of heterogeneity.Result:  The outcomes of 899 testicular torsion patients from eight studies were evaluated. Our study found an increased hospitalization rate for patients with testicular torsion (incidence rate ratio = 1.60, 95% confidence interval [CI]: 1.27-2.03; p = 0.001). Despite a significant increase in the duration of symptoms during the COVID-19 pandemic (weighted mean difference = 11.04, 95% CI: 2.75-19.33; p = 0.009), orchiectomy rates did not increase (odds ratio = 1.33, 95% CI: 0.85-2.10; p = 0.147).Conclusion:  During the COVID-19 pandemic, hospitalization rates for testicular torsion and the duration of symptoms among children increased significantly. Moreover, the rate of orchiectomy did not increase during the pandemic, indicating that pediatric emergency services have remained efficient and have prevented an increase in the number of orchiectomies performed despite pandemic-related closures and delays in transporting patients to medical care. [ABSTRACT FROM AUTHOR]

All life stages of I O. communa i were raised at the control temperature of 28 °C; experimental temperatures of 40 °C, 42 °C, or 44 °C were imposed from 12:00 to 15:00 daily to different life stages of I O. communa i placed in respective environmental chambers until a generation completed. All life stages of I O. communa i were raised at the control temperature of 28 °C; experimental temperatures of 40 °C, 42 °C, or 44 °C were imposed from 12:00 to 15:00 daily to different life stages of I O. communa i placed in respective environmental chambers until a generation completed. All life stages of I O. communa i were raised at the control temperature of 28 °C; experimental temperatures of 40 °C, 42 °C, or 44 °C were imposed from 12:00 to 15:00 daily to different life stages of I O. communa i placed in respective environmental chambers, until a generation completed. [Extracted from the article]

Knowledge of water movement from the hillslope critical zone is important for water management. However, the runoff process resulting from extreme rainfall events remains unclear due to rare field‐based natural monitoring data. We investigated rainwater infiltration and runoff generation processes in two plots with deep and relatively shallow soil thicknesses (66 vs. 35 cm depth on average, respectively) on karst hillslopes. Rainwater, soil water and lateral discharge runoff in the soil‐epikarst system were monitored using hydrometric and 18O isotope methods in September 2020, which was the wettest month on record at the study s, including three normal rainfalls (29.6 mm in 8.5 h, 25 mm in 8.5 h, and 27.4 in 3.5 h) and three extreme rainstorms (335 mm in 11.5 h, 77.8 mm in 9 h, and 129.2 mm in 5 h). Soil moisture and water table responded rapidly (<30 min) during the extreme rainfall. However, the soil‐epikarst interface exhibited the strongest stability (coefficient variation [CV] < 8.18%) and collected more pre‐event water, reflected by the isotopic signature of the soil water. Accordingly, low permeability at the soil‐epikarst interface played an important role in buffering rainwater infiltration. Controlled by infiltration‐excess and saturation‐excess runoff mechanisms, the contribution of surface runoff to total discharge was less than 3% during normal rainfall events, which was significantly less than that during extreme rainfall events (13%–60%). This was supported by the evolution of δ18O values of surface runoff that were similar to rainwater and more 18O‐depleted than that of subsurface runoff. Higher rainfall intensity which exceeded soil permeability during extreme rainstorms further increased the possibility of exceeding infiltration‐saturation processes. For the deep soil plot (DSP), surface runoff (>44%) dominated the extreme rainfall process; while for the shallow‐soil plot (SSP), surface runoff (60%) dominated only during the maximum rainfall events. Moreover, the surface runoff contribution to total runoff in DSP was greater than that in SSP. Surface runoff from slopes with thicker soil layers is an important part of karst watershed flood processes in extreme rainfall events, which should be considered carefully for water resource management. Highlights: Hydrometric and isotope methods are used to assess extreme hydrological processes.The surface runoff of extreme rainfalls is much higher than that of normal rainfall.The infiltration‐excess mechanism dominates the surface runoff of extreme rainfall.Slopes with thicker soil layers are more vulnerable to flooding in the karst region. [ABSTRACT FROM AUTHOR]

Background: Hepatocarcinogenesis is reportedly correlated with abnormal m6A modifications; however, it is unknown whether m6A RNA methylation regulators facilitate the occurrence of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Thus, we constructed an m6A-related model that may enhance HBV-related HCC prognosis. Methods: Gene signatures of HNRNPA2B1 and RBM15 were generated by univariate and Lasso Cox regression analyses using the gene set and clinical information from The Cancer Genome Atlas (TCGA) database. High-risk and low-risk groups were confirmed based on the gene signature model. Furthermore, we validated the predictive roles of the two genes for overall survival (OS) in the GSE14520 dataset. The relative expression of 22 paired mRNAs was measured using quantitative real-time polymerase chain reaction (qRT-PCR) analysis to determine whether the two genes had a predictive role in our Guilin cohort. Results: The differences in OS between the high-risk and low-risk groups were statistically significant in the TCGA (p = 0.003) and GSE14520 (p = 0.045) datasets, but not in the Guilin cohort, owing to differences in clinical information among the three cohorts (mainly the TNM stage and survival state). Stratified analysis of TNM stages showed that the two-gene signature acted as a prognostic indicator of HBV-related HCC patients in the early TNM stage; both TCGA and GSE14520 cohorts showed statistical significance. Moreover, multivariate Cox regression analysis indicated that the two-gene signature was an independent factor for predicting prognosis (HR = 1.087, 95% CI: 1.007–1.172). Correlation analysis between the gene signature and clinical features revealed that the risk stratification was significantly correlated with grade and survival state. Finally, Gene Set Enrichment Analysis (GSEA) revealed that the KEGG pathways associated with the cell cycle, DNA replication, the spliceosome, repair, and metabolism-related processes were all significantly enriched in the high-risk group. Among the enriched genes, the expression levels of the replication protein RPA1 and the pre-mRNA splicing factor SF3B1 were significantly upregulated in the high-risk group. These results might help in elucidating the underlying molecular mechanisms of HBV-related HCC. Conclusions: Our data may provide new predictive signatures and potential therapeutic targets to identify and treat HBV-related HCC patients in the early disease stage. [ABSTRACT FROM AUTHOR]

Abstract Soil carbon (C), nitrogen (N), and phosphorus (P) are some of the most important indicators of soil quality, especially in fragile ecological environments with shallow soils. However, the differences in their variations and influencing factors related to scale in karst areas remain unclear. Therefore, variations in surface soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) distributions and their determinant factors were quantitatively analyzed at different scales (i.e., region, sub-region, and catchment) in a typical karst area, southwest China. Overall, both soil nutrient variations and the determinant factors involved varied with scale. The coefficients of variation for SOC, TN, and TP increased significantly from catchment to sub-region scales but changed only slightly between sub-region and region scales. At region and sub-region scales, lithology only affected TP significantly, while land use affected all soil nutrients significantly. However, the explanations for TP variation by lithology and for SOC, TN, and TP variations by land use increased by 12.2, 7.0, 11.0, and 12.8% at sub-region scale over the values observed at region scale, respectively. When lithology and land use were controlled, soil depth was observed playing an important role in soil nutrients at the three studied scales. At region and sub-region scales, other factors related to soil texture (clay, silt, or sand content), topography (elevation or TWI), and climate (MAT or MAP) were selected as significant variables and accounted for a larger proportion of nutrient variation. However, at catchment scale, bare rock rate and micro-topography (e.g., slope) explained soil nutrient variation to a larger proportion. Therefore, elucidation of the role of factors influencing soil nutrients at different scales can provide a guide for soil quality assessment in karst areas. Highlights • Both soil nutrient variation and its determinant factors varied with scale. • Lithology explained 12.2% more of TP variation at sub-region than at region scale. • Land use explained soil nutrient variation best at the sub-region scale. • Bare rock rate affected cropland soil nutrients significantly at the three scales. [ABSTRACT FROM AUTHOR]

Abstract Precipitation in the karst regions of southwest China is plentiful, however, soils are shallow and highly permeable, which results in rapid transportation of surface water through a soil profile. Therefore, the presence and amount of water stress in a soil layer can be unpredictable. This study will investigate the soil water conditions on karst hillslopes in southwest China through dynamic in situ observations of profile soil moisture (θ). Three profiles at two slope positions on two shrub-grasslands (S1 and S2) were selected, respectively. At each profile, TDR 100 probes were set at 10, 20, 30, 50, and 70 cm and for 100 cm, only on downslopes. Soil samples (undisturbed and disturbed) were collected to measure basic physical and chemical properties. Precipitation and θ were monitored manually each week between July 15, 2012 and November 25, 2014. Results show that soil properties, which have an important effect on θ , varied among slope positions and between the two hisllslopes. A higher clay content, which led to greater water holding capacity, explained a higher θ in downslopes and on S2. Shallow soil layers (0–30 cm), especially in the coarse textured soil layers of S1, were susceptible to water stress due to the limited availability of soil water. Water stress was low during water supplying (December through April) and relatively stable periods (May to June). However, during water consuming periods (July to November), profile θ decreased greatly which resulted in severe water stress for the whole profile. Although precipitation was seasonally uneven, based on weekly observations, profile θ on both hillslopes was not temporally active (coefficients of variation of θ was smaller than 20%) and the variance of each depth was similar. Generally, the effects of precipitation on θ can last two (0–50 cm) to five (70–100 cm) weeks. Nevertheless, θ of downslope deep soil, which was (or near) saturated all year round, was barely affected by precipitation. These results can provide valuable information for hydrological models and rational strategies for ecological restoration designing in karst regions. Highlights • Soil water conditions of two karst shrublands were investigated. • Shallow soil layers (0–30 cm) were susceptible to water stress. • Soil moisture (θ) was not active with small variances at all soil depths. • Precipitation affected θ within two (above 50 cm) to five (under 70 cm) weeks. • Saturated deep soil layers were not obviously affected by precipitation. [ABSTRACT FROM AUTHOR]

Extreme heat in summer is frequent in parts of China, and this likely affects the fitness of the beetle Ophraella communa, a biological control agent of invasive common ragweed. Here, we assessed the life history parameters of O. communa when its different developmental stages were exposed to high temperatures (40, 42 and 44 °C, with 28 °C as a control) for 3 h each day for 3, 5, 5, and 5 days, respectively (by stage). The larval stage was the most sensitive stage, with the lowest survival rate under heat stress. Egg and pupal survival significantly decreased only at 44 °C, and these two stages showed relative heat tolerance, while the adult stage was the most tolerant stage, with the highest survival rates. High temperatures showed positive effects on the female proportion, but there was no stage-specific response. Treated adults showed the highest fecundity under heat stress and a similar adult lifespan to that in the control. High temperatures decreased the F1 egg hatching rate, but the differences among stages were not significant. Negative carry-over effects of heat stress on subsequent stages and progenies' survival were also observed. Overall, heat effects depend on the temperature and life stage, and the adult stage was the most tolerant stage. Ophraella communa possesses a degree of heat tolerance that allows it to survive on hot days in summer. [ABSTRACT FROM AUTHOR]

Soil carbon (C), nitrogen (N), and phosphorus (P) are the main soil nutrients required for plant development and their stoichiometric ratios are important indicators of ecosystem functions. However, there have been few studies on the effects of land use and lithology on soil nutrients and stoichiometric ratios, especially in karst areas with extremely fragile geology and intensive human disturbance. To evaluate the synergistic effect of land use and lithology, soil samples at depth of 0–15 cm were collected from five land-use types (arable land, plantation forest, grassland, shrubland, and secondary forest) over three lithologies (karst dolomite and limestone and non-karst clasolite) in a typical karst area in southwest China. For natural succession, grassland, shrubland, and secondary forest corresponded to the early, middle, and late successional stage after agricultural abandonment, while from arable land to plantation forest can be treated as a manual reversion after agricultural abandonment. The results showed that, in dolomite, soil organic C (SOC) and total N (TN) increased continuously with natural succession and increased in plantation forest compared to arable land. Total P (TP) continued to decrease from arable land to grassland and then to shrubland. In limestone, SOC and TN did not follow the same pattern because SOC and TN were slightly higher in grassland than shrubland, while TN was slightly lower in plantation forest compared to arable land. TP was remarkably higher in arable land than the other land-use types. For clasolite, SOC was highest in grassland, while TN was not significantly different among land-use types. Compared to arable land, TP was lower in other types of land use. These soil nutrient characteristics led to various stoichiometric ratios under the five land-use types over different lithologies. Therefore, ecological restoration projects based on land use conversion should consider differences in regional lithology and human disturbance. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the effects of soil physicochemical properties and environmental factors on the spatial patterns of surface soil water content (SWC) based on the state-space approach and linear regression analysis. For this purpose, based on a grid sampling scheme (10 m × 10 m) applied to a 90 m × 120 m plot located on a karst hillslope of Southwest China, the SWC at 0–16 cm depth was measured 3 times across 130 sampling points, and soil texture, bulk density (BD), saturated hydraulic conductivity (Ks), organic carbon (SOC), and rock fragment content as well as site elevation (SE) were also measured at these locations. Results showed that the distribution pattern of SWC could be more successfully predicted by the first-order state-space models (R2 = 67.5–99.9% and RMSE = 0.01–0.14) than the classic linear regression models (R2 = 10.8–79.3% and RMSE = 0.11–0.24). The input combination containing silt content (Silt),Ks, and SOC produced the best state-space model, explaining 99.9% of the variation in SWC. And Silt was identified as the first-order controlling factor that explained 98.7% of the variation. In contrast, the best linear regression model using all of the variables only explained 79.3% of variation. [ABSTRACT FROM PUBLISHER]

Zhenbao pill (ZBP) is a type of traditional Mongolian medicine that contains 241 ingredients such as flavonoids, anthraquinones, triterpenoids, sterols, and Calculus bovis, which are mainly used for treating neurological diseases in clinical practice. In this study, we established an Alzheimer's disease (AD)-mimetic symptomatic zebrafish model by AlCl 3 treatment and investigated the therapeutic effect of ZBP on the AD-mimetic zebrafish model. The results revealed that AlCl 3 treatment led to behavioral impairment, induced apoptotic cell (body) in the brain, increased acetylcholinesterase (AChE) activity, and decreased the ACh content in zebrafish. After treatment with ZBP, 16 μg/mL ZBP could alleviate the behavioral disorder of zebrafish larvae. This effect was found superior to the effect of the cholinesterase inhibitor donepezil hydrochloride. The analysis of transcriptomics data revealed that ZBP mainly acted on apoptosis, the p53 signaling pathway, and the enrichment of the AChE-associated pathway. Furthermore, the overexpression of AChE RNA produced similar AD-mimetic disorders, whereas AChE-gene knockdown (AChE-MO) decreased the AChE activity and alleviated the AD-mimetic symptoms. These results suggested that ZBP is a potential cholinergic-enhancing drug, which can be used for the treatment of AD in the future. [Display omitted] • ZBP inhibited AlCl 3 -induced dyskinesia in zebrafish larvae. • ZBP-reduced apoptosis bodies in the brain of zebrafish larvae caused by AlCl 3. • AlCl 3 -induced AChE mRNA expression and AChE activity in zebrafish larvae. • AChE-gene knockdown inhibited AlCl 3 -induced dyskinesia and apoptosis. • ZBP rescues dyskinesia via inhibition of AChE in zebrafish larvae. [ABSTRACT FROM AUTHOR]

[Display omitted] • Runoff connectivity on a karst hillslope are identified by isotopic signals. • The proportion of young water and event water decreases from upslope to downslope. • Runoff from the upslope is connected to the downslope by the soil–bedrock interface. • Soil-epikarst structure controls the hydrological connectivity of karst hillslopes. Hydrologic connectivity along the hillslope critical zone is essential for the transmission of water, solutes, and nutrients to streams. However, the influences of critical zone structure on hydrological connectivity are not adequately understood, especially for hillslopes with complex topography. We investigated the hydrological connectivity along different topographical positions of two adjacent dolomite hillslope plots in southwest China: a deep soil plot (average value: 66 cm) and shallow soil plot (average value: 35 cm). We characterized the dynamics of multiple-interface runoff and soil water based on observations of stable isotopes (δ18O and δD) and hydrometric monitoring, and computed the lc -excess, young water fraction (y w), and hydrograph separation from June 2020 to July 2021. On both hillslopes, soil depth gradually increased from up-slope to down-slope, and the contribution of event water and y w to soil water gradually decreased (100 % to 69 %). In the vertical depth, a sudden decrease in the contribution of y w (98 % to 47 %) and event water (44 % to 11 %) in the down-slope of the soil-epikarst interface was observed. These results indicate that the infiltration of rainwater from up-slope to down-slope was altered by vertical flow to lateral flow, which was connected through the soil-epikarst interface and finally converged in the low-lying area. Contrary to expectations, the contribution of y w at the soil-epikarst interface was lower in the shallow soil plot (43 %) than in the deep soil plot (71 %). As a supplement, moisture at the soil-epikarst interface was significantly higher in the shallow soil plot. This indicates that the renewal cycle of groundwater was slower in shallow soil-covered hillslopes not only because almost all rainwater (∼98 %) entered the soil-epikarst to redistribute as well as the higher water storage area in the soil-epikarst interface. Accordingly, the soil-epikarst structure, which is differentiated by soil depth, controls hillslope hydrological connectivity and groundwater storage capacity in the karst region of southwest China. [ABSTRACT FROM AUTHOR]

Summary Karst spring/stream discharge reflects the global configuration of the aquifer. However, quantitative description of the aquifer structure such as effective porosity ( n eff ) and water storage capacity by the discharge analysis is difficult because of the complex conduit/fracture system. This study attempted to quantify the characteristics of karst aquifer based on discharge recession and time series analysis methods. Three recession models, including modified Maillet, Mangin and Boussinesq models, were evaluated to choose the most suitable one for analyzing the aquifer structure, and auto-correlation and cross-correlation functions were applied to study the aquifer response in both year and rainfall event time scales. The results showed that the modified Maillet model was more suitable in the study catchment with Mangin model overestimating and Boussinesq model underestimating the discharge. The n eff was 3.73% for the total aquifer, and it was 0.07%, 0.33% and 3.33% for the conduit, fracture and matrix, respectively. Based on a case study of a rainfall event with precipitation of 68 mm, the water volumes drained by the three media were 25.43%, 33.40% and 41.17%, respectively. This indicates that, although conduit network is not very developed with lower n eff , it is still an important water transmissive element (draining more than a quarter of water after the rainfall event). The memory time of the aquifer was 4 days for the year scale and 8 h for the rainfall event (68 mm) scale. This demonstrates that the aquifer has a well developed drainage system with a quick response to the rainfall. The above results provide further insights for hydrological processes modeling and water resources management for the small catchment in karst regions. [ABSTRACT FROM AUTHOR]

Soil moisture ( θ ) and its stable isotope values are two of the most commonly used parameters for studying hydrological processes in soils. Despite their unique ability to aid in distinguishing between soil water evaporation and plant transpiration, the spatial variability of soil water isotope values is not fully understood. In the current study, 10 m × 10 m grids were established within a 90 m × 120 m plot on a highly heterogeneous karst hillslope. Two sampling campaigns were conducted during the early growing season, on April 15, and during the mid-growing season, on August 18, 2011. Stratified soil samples were collected from the shallow soil layer (0–30 cm) to measure θ and its stable isotope values, which were represented by soil water δD values (δD θ ). Related soil properties, land cover and topography were also measured and treated as influencing factors. On both sampling dates, θ decreased with depth, while δD θ stayed constant for all soil layers and were similar to the most recent rainfall values. Additionally, the variance of δD θ was smaller than that of θ , especially on August 18 when the most recent rainfalls had similar δD values. The high contrast between θ and δD θ caused the impacts of other factors on δD θ to be masked by the impact of the recent rainfall. Soil moisture presented a moderate to strong spatial dependence, which was consistent with the spatial variability of the influencing factors that were significantly correlated with θ . Soil water δD value exhibited weak spatial dependence and random spatial patterns that were different from the other influencing factors. Moreover, significant correlations between these same influencing factors and δD θ disappeared after a partial analysis with θ as a controlled variable, which means δD θ was indirectly affected by these influencing factors through θ . This suggests that the spatial variability of δD θ was being controlled at fine scales. Our results highlight the importance of analyzing the spatial variability of δD θ , its influencing factors and θ in shallow soil layers separately. [ABSTRACT FROM AUTHOR]

Reliable estimation of erosion in karst areas is difficult because of the heterogeneous nature of infiltration and sub-surface drainage. Understanding the processes involved is a key requirement for managing against karst rock desertification. This study used the revised Universal Soil Loss Equation (RUSLE) to estimate the annual soil erosion rates on hillslopes and compared them with 137 Cs budget in the depressions at two typical karst peak-cluster depression basins in northwest Guangxi, southwestern China. Runoff plots data were used to calibrate the slope length factor ( L ) of the RUSLE model by adjusting the accumulated area threshold. The RUSLE model was sensitive to the value of the threshold and required DEMs with 1 m resolution, due to the discontinuous nature of the overland flow. The average annual soil erosion rates on hillslopes simulated by the RUSLE were 0.22 and 0.10 Mg ha − 1 y − 1 during 2006 through 2011 in the partially cultivated GZ1 and the undisturbed GZ2 basins, respectively. The corresponding deposition rates in the depressions agreed well with the 137 Cs records when recent changes in precipitation and land use were taken into consideration. The study suggests that attention should be given to the RUSLE- L factor when applying the RUSLE on karst hillslopes because of the discontinuous nature of runoff and significant underground seepage during storm events that effectively reduces the effects of slope length. [ABSTRACT FROM AUTHOR]

Abstract: Rock fragments (>5mm in diameter) at the soil surface and within the topsoil have a large effect on the intensity of various hydrologic and geomorphic processes. However, little information is available on the spatial distribution of rock fragments in subtropical regions. The objective of this paper was to investigate the relationship between the spatial distribution of rock fragments and landforms on two different steep karst hillslopes in northwest Guangxi, southwest China. On the first hillslope (a disintegrated landslide failure) with the presence of several large rock outcrops (>2m in height), the spatial distribution of rock fragment cover had no obvious relationship with topographic position except that the mean cover percentage of small rock fragments (5–20mm) decreased from bottom to top. On the second hillslope (an avalanche slope) without the presence of large rock outcrops, the mean total rock fragment cover (5–600mm) increased from bottom (5%) to top (21%) with decreasing variability and rock fragments with various sizes (5–20, 20–75, and 75–250mm) showed a similar increasing trend. The mean total rock fragment cover increased linearly with slope gradient on the second hillslope and tended to increase and then decrease with gradient but their relationship was not obvious on the first hillslope. This indicated that the spatial distribution of surface rock fragment cover had a close relationship with the presence of large rock outcrops and slope gradient. However, the median diameter (D50) of the surface rock fragments had an increase–decrease trend with slope gradient but there was no obvious relationship on both hillslopes with low overland flow. Therefore, the dominant factor for the spatial distribution of rock fragment cover and size at the soil surface might not be soil erosion by water, but slope gradient, vegetation and geomorphologic condition of the slope. The mean total volumetric rock fragment content (5–250mm) within the topsoil (10–20cm thick) increased linearly from bottom (16%) to top (39%) with slope gradient on the first hillslope, and had a logarithmic increase from bottom (10%) to top (27%) with gradient on the second hillslope. This suggested that rock fragment content within the topsoil was mostly controlled by slope gradient and topographic positions and had not a close relationship with the presence of large rock outcrops. [Copyright &y& Elsevier]

Vegetation restoration effectively prevents soil degradation. However, the changes in soil properties that occur in fragile ecosystems in response to vegetation restoration are unclear. The aim of this study was to investigate the effects of vegetation restoration on soil physicochemical properties and saturated hydraulic conductivity (Ks) at different elevations. Restoration strategies included natural shrubland (NR), managed plantation forest (PF), cropland (CR), and secondary forest (SF). Topsoil (0–15 cm) samples were collected from seven counties in the karst region of southwest China. The soil nutrients were significantly (p < 0.05) higher in both NR and PF than in CR but were lower in SF. Soil physical properties (bulk density, porosity, texture, and Ks) were significantly (p < 0.05) different between CR and SF but not significantly different between NR and PF. Hence, the short restoration period (~15 years) had a stronger influence on soil nutrients than on soil physical properties. The soil properties following different land-use types were affected by elevation. For SF and PF, soil Ca, total nitrogen, and sand content were significantly (p < 0.05) negatively correlated with elevation. For NR, only sand content was significantly (p < 0.05) negatively correlated with elevation. No soil parameters were significantly correlated with elevation in CR. Soil nutrients increased to a greater extent in the low-elevation area (150–500 m) than in the high-elevation (1000 to 1200 m) areas. This discrepancy could be explained by the relatively increased biomass after vegetation restoration. Clay content variation was the main factor controlling Ks variation. The change in clay content was greater in low-elevation areas than in higher-elevation areas, where higher weathering and erosion rates were caused by strong hydrothermal conditions. Accordingly, the present study showed that the variations in soil properties observed after vegetation restoration are influenced by both land-use types and elevation. • The influence of elevation & land use type on karst soil properties were assessed. • The short restoration period (~15 y) had a stronger influence on soil nutrients. • Soil nutrients increased greater in low-elevation than in high-elevation areas. • Clay content was the main factor controlling Ks variation under restoration. [ABSTRACT FROM AUTHOR]

Summary: Large-scale vegetation restoration has been helpful to prevent serious soil erosion, but also has aggravated water scarcity and resulted in soil desiccation below a depth of 200cm in the Loess Plateau of China. To understand the dynamic mechanism of soil desiccation formation is very important for sustainable development of agriculture in the Loess Plateau. Based on natural and simulated rainfall, the characteristics of soil water cycle and water balance in the 0–400cm soil layer on a steep grassland hillslope in Changwu County of Shaanxi Loess Plateau were investigated from June to November in 2002, a drought year with annual rainfall of 460mm. It was similarly considered to represent a rainy year with annual rainfall of 850mm under simulated rainfall conditions. The results showed that the temporal variability of water contents would decrease in the upper 0–200cm soil layer with the increase in rainfall. The depth of soil affected by rainfall infiltration was 0–200cm in the drought year and 0–300cm in the rainy year. During the period of water consumption under natural conditions, the deepest layer of soil influenced by evapotranspiration (ET) rapidly reached a depth of 200cm on July 21, 2002, and soil water storage decreased by 48mm from the whole 0–200cm soil layer. However, during the same investigation period under simulated rainfall conditions, soil water storage in the 0–400cm soil layer increased by only 71mm, although the corresponding rainfall was about 640mm. The extra-simulated rainfall of 458mm from May 29 to August 10 did not result in the disappearance of soil desiccation in the 200–400cm deep soil layer. Most infiltrated rainwater retained in the top 0–200cm soil layer, and it was subsequently depleted by ET in the rainy season. Because very little water moved below the 200cm depth, there was desiccation in the deep soil layer in drought and normal rainfall years. [Copyright &y& Elsevier]

Abstract: Soil desiccation usually takes place below the depth of soil affected by rainfall infiltration (about 1–3 m) with relatively low water content, and is one kind of particular hydrological phenomena in semi-arid and semi-humid regions of the Loess Plateau in China. This desiccation results from the excessive depletion of deep soil water by artificial vegetation and long-term insufficient rainwater supply, which is difficult to disappear with land use change. Due to the influence of global warming during 1950–2000, large-scale vegetation rehabilitation aggravated water scarcity and led to soil desiccation in the deep soil layer in the Loess Plateau. From southeast to northwest, soil desiccation becomes more intensive with lower water content and bigger range in depth due to drier climate and lower water holding capacity. The range of soil desiccation has a close relationship with root distribution of plant, and its intensity varies with the types and ages of vegetation. The climate drought, soil properties and soil water cycle characteristics might be the precondition for the occurrence of soil desiccation, and artificial vegetation with improper type and exorbitant productivity could have accelerated this process in range and intensity. Soil desiccation has obviously negative effects on water cycle in soils, greatly reduces the anti-drought capacity of plants, and heavily influences the growth and natural succession of vegetation. In order to reduce the range, intensity, and negative effects of soil desiccation, proper types of vegetation should be selected according to rainfall and soil water conditions, and the control of vegetation density and productivity should be considered together with soil-water conservation measures. [Copyright &y& Elsevier]

Plantations, as a form of vegetation restoration, play a critical role in the recent greening of the earth. However, the sustainability of the restored vegetation under precipitation changes has rarely been estimated, largely because of a lack of knowledge about the related plant water adaptation. In the current study, six tree species, including evergreen and deciduous, were selected from a typical karst forest types in Southwest China, a hotspot of earth greening. Root water uptake depth and hydraulic-related traits of stem and leaf were studied. Our results showed that, in the wet season, the evergreen species mainly rely on soil water sources from a depth of 0–30 cm (49.74%), while the deciduous use deeper layers of 30–70 cm in depth (47.58%). In the dry season, the deciduous species shed their leaves while the evergreens utilized soil water at a depth of 0–10 cm with an average absorption of 66.96%. The evergreen species exhibit higher xylem-cavitation resistance (reflect by P 50) and leaf-turgor maintenance capacity (reflect by Ψ tlp) than the deciduous. The significant correlations between plant water uptake depth and water potential, and hydraulic traits and water uptake depth indicate the different water adaptation strategies of evergreen and deciduous. In detail, evergreen species that rely on shallower water sources exhibit a larger diurnal range of leaf water potential, more xylem-cavitation resistant and leaf-turgor maintenance capacity. In contrast, deciduous species, with deeper water uptake, show narrower diurnal range of leaf water potential with lower drought resistance of stem and leaves. Our results highlight the probable divergent response (such as growth restriction and hydraulic failure) of evergreen and deciduous plantation tree species to the changing precipitation patterns under climate change. • The sustainability of the restored vegetation has rarely been estimated due to the lack of plant water adaptation research. • Evergreens with shallower water sources show larger range of water potential, higher drought resistance of stem and leaves. • Deciduous species with deeper water uptake show narrower diurnal range of water potential and lower drought resistance. • There are divergent responses of evergreen and deciduous to the changing precipitation patterns under climate change. [ABSTRACT FROM AUTHOR]

Various water transmitting media are related to highly variable water source compositions, which limit the understanding of the aquifer structure and hydrological processes in a karst catchment. This study aims to understand the variation in water contribution by matrix, fissure, and conduit flows during storm and seasonal scales based on discharge, electrical conductivity (EC), and nitrate measurements of stream water in a typical dolomite catchment during 2017–2018 and discusses the hydrological response mechanism of a karst aquifer to rainfall characteristics. Time-series analyses of discharge and EC indicated that the rapid response time (mean lag time < 1 h) was mainly controlled by rainfall intensity, and the lag time decreased significantly when the rainfall intensity was lower than 15 mm/h. However, the mean discharge was dominated by the rainfall amount and antecedent moisture state. Hydrograph separation based on nitrate indicates that the contribution of soil water was irrelevant for recharging the stream during a non-rain period, whereas epikarst water contributed more than 83.2% of the total flow during a rainfall event. As indicated by the EC frequency distribution analyses, the contribution ratios of the surface, conduit, fissure, and matrix flows were 1:1.8:2.1:7.1, 1:1.6:5.3:6.3, and 0:0:0:1 during stormy, heavy, and light rainfall events, respectively. These parameters indicate that the degree of karstification was low in the karst aquifer. Seasonal frequency distribution analyses of EC indicate that higher rainfall amounts and rainfall intensities during the wet season promoted the contribution of conduit flow to approximately 11.4% of the total flow; however, matrix flow dominated the recharge of the streamflow and its contribution was more than 55.6% during each season. Our results suggest that the permeability of the epikarst matrix dominates the storage and transfer functions in dolomite karst aquifers with low karstification. Unlabelled Image • Rainfall intensity controls lags to peak discharge of stream flow. • Rainfall amount and antecedent moisture state dominate mean discharge of stream. • Dolomitic epikarst water contributes more than 83.2% of the total stream flow. • Maximum ratios of conduit flow are 18% and 11% in storm and seasons, respectively. • Matrix properties dominate storage and transfer function in dolomite karst aquifer. [ABSTRACT FROM AUTHOR]

• Most of stream water were recharged by underground flow in dolomite catchment. • Epikarst water dominates the recharge of springs and stream in small watershed. • Rock outcrop ratio and karstic degree enhance spring's sensitivity to rainfall. • Subsurface flow controlled the rapid fluctuating of stream discharge in wet season. Quantifying and understanding recharge behavior of aquifers in complex hydrogeological systems is challenging, which limits our ability to manage water resources in karstic areas. In this study, we analyzed the seasonal recharge sources and processes of a stream, an intermittent spring, and a perennial spring in a small dolomitic catchment. Weekly monitoring of stable isotopes and chemical characteristics and daily hydrological data of these waters was performed in 2017 and 2018. There were broad seasonal variations in rainfall isotopes, with more negative values observed in the wet season and more positive values observed in the dry season, while narrow ranges were observed in spring and stream waters. Such values plotting on a LMWL represented a homogeneous mixing of rainfall without the effective evaporation effect. Hydrograph separation showed that the mean proportion of old water was approximately 94% for the springs and stream, which indicated a mixing mechanism in recharge processes. The mean residence time was approximately 23 weeks for spring 1, 201 weeks for spring 2, and 43 weeks for stream. The significant difference between springs was attributed to the combined effects of relatively higher proportions of rocky outcrops, thinner soil–epikarst, and better karstic development in the aquifer of spring 1, which enhanced the sensitivity to rainfall. The stream was recharged by waters from hillslopes, which mixed extensively in the depression, accompanied by soil–epikarst interaction. However, only approximately 1.5% of total stream flow was recharged by springs annually, and most of the stream was recharged by water through underground paths, based on the discharge analyses. Moreover, stream was recharged by subsurface flows, which were considerably affected by soil, leading to the fluctuating stream discharge characteristics during the wet season. The results suggest that greater attention should be paid to the roles of near-surface soil–epikarst architecture in hydrological processes. [ABSTRACT FROM AUTHOR]

• Annual precipitation and runoff showed similar changes with turning points in 2002. • Ecological restoration had a great impact on runoff in karst basins. • Increases in NDVI negatively related to the proportions of karst landscape. • Revegetation decreased flood season runoff and increased non-flood season runoffs. Ecological restoration changes land cover types and management practices. However, understanding of their hydrological response is limited, especially in karst ecosystems, which are vulnerable to environmental changes. This study aimed to identify the spatial variability of the hydrological response in a mesoscale karst basin to climate change and ecological restoration. We examined changes in hydrological variables and normalized difference vegetation index (NDVI) from 1985 to 2015 in Longjiang River Basin (LRB) and its three main sub-basins, namely Huanjiang (HJB), Zhongzhouxiaojiang (ZZB), and Dongxiaojiang (DXB) sub-basins. The proportions of karst landscapes (POK) were 81, 66, 61, and 26%, respectively. Three independent quantitative methods were employed to distinguish the relative contributions of climate change and human activity. Annual runoff showed a good linear correlation with precipitation in all the basins, with insignificantly lower average values during 2003–2015 than during 1985–2002. The relative contribution of precipitation to annual runoff change varied from 17.5 to 52.9%. At a seasonal scale, flood season precipitation and runoff decreased with similar patterns of annual variation, whereas non-flood season values increased from 1985–2007 to 2008–2015. The quantitative results showed that the relative contribution rates of human activity to non-flood season runoff change were strongly linked to POK values and related vegetation changes. Annual NDVI improved after the implementation of ecological restoration projects, with change rates negatively related to POK values. Human activity was the dominant cause of increased non-flood season runoff in the LRB and HJB (accounting for 57 and 78%, respectively), whereas increases in non-flood season runoff in the ZZB and DXB were mainly caused by precipitation changes (accounting for 84 and 172%, respectively). These findings highlighted the facts that ecological restoration had changed hydrological processes and seasonal-scale analyses might therefore facilitate a better understanding of runoff changes in karst basins. [ABSTRACT FROM AUTHOR]

• Underground soil loss relative to the crown cross-section of grike wall is defined. • Underground soil loss form via fully filled grike is overlying soil moving down. • Underground soil loss form via partially filled grike is eroded soil depositing. • The annual underground soil loss intensity via the sample grikes was strong. Determining the mechanism of rocky desertification by investigating the sediment transport process in carbonate aquifers with the great mixture of various karst conduit features presents severe difficulties. This study put its focus on the overlying soil entering the master small-scale surface karst negative (SSKN) feature, the tapering grike on limestone hillslopes. The objective is to assess the primary forms and the annual rates of underground soil loss relative to the crown cross-section of the grikes wall. The tapering grikes were differentiated into the fully and partially filled ones based on the current filling status of the soil. Through the analysis of the possible scenarios, the stable carbon isotope and 137Cs records of soil in the sample grikes in Southwest China, the underground soil loss form was mainly inferred as the downward creeping of overlying soil mass via the fully filled one, and the deposition of eroded overlying soils into the partially filled grike. The formula of inside space forming rate determined by the bedrock dissolution rate and the grike shape, was proposed for obtaining the current potential annual underground soil loss rate via the fully filled grike, the calculation result of which for the sample was 275.2 t km-2 y-1. The 137Cs identification method of the sediment deposition depth was used to estimate the average annual underground soil loss rate since 1963 via the partially filled grike, which was 3094.4 t km-2 y-1 for the sample. The calculations indicated that the underground soil loss via the tapering grikes contributed a lot to the overlying soil reduction in the process of karst rocky desertification. More attentions should be given to assess the underground soil loss via all the SSKN features on the whole hillslope scale and evaluate the impacts of human activities. [ABSTRACT FROM AUTHOR]

Summary: Root access to bedrock water storage or groundwater is an important trait allowing plant survival in seasonally dry environments. However, the degree of coordination between water uptake depth, leaf‐level water‐use efficiency (WUEi) and water potential in drought‐prone plant communities is not well understood.We conducted a 135‐d rainfall exclusion experiment in a subtropical karst ecosystem with thin skeletal soils to evaluate the responses of 11 co‐occurring woody species of contrasting life forms and leaf habits to a severe drought during the wet growing season.Marked differences in xylem water isotopic composition during drought revealed distinct ecohydrological niche separation among species. The contrasting behaviour of leaf water potential in coexisting species during drought was largely explained by differences in root access to deeper, temporally stable water sources. Smaller‐diameter species with shallower water uptake, more negative water potentials and lower WUEi showed extensive drought‐induced canopy defoliation and/or mortality. By contrast, larger‐diameter species with deeper water uptake, higher leaf‐level WUEi and more isohydric behaviour survived drought with only moderate canopy defoliation.Severe water limitation imposes strong environmental filtering and/or selective pressures resulting in tight coordination between tree diameter, water uptake depth, iso/anisohydric behaviour, WUEi and drought vulnerability in karst plant communities. [ABSTRACT FROM AUTHOR]

Background: To explore reasons for the failure of noninvasive prenatal test (NIPT) for cell‐free fetal DNA (cffDNA) in maternal peripheral blood, and discuss appropriate treatment schemes after the failure of the test. Methods: Altogether 41,136 pregnant women participated in NIPT. Blood samples were taken again from pregnant women who failed the first blood collection upon their informed consent. Prenatal genetic counseling or prenatal diagnosis was recommended for pregnant women with final NIPT failure. Results: The first failure rate of NIPT was 0.737% (303/41136), and the reason for the failure was the low ratio of cffDNA in 135 (44.6%) of the 303 pregnant women. After the second or third blood sampling, the final failure rate was 0.182% (75/41136). The low ratio of cffDNA was the main reason for test failure in 42 (56.0%) of the 75 pregnant women who finally failed NIPT, among whom 44 (58.7%) had underlying diseases, including 21 (47.7%) with more than two coexisting underlying diseases. Only 27 (36.0%) of the 75 pregnant women with NIPT failure underwent interventional prenatal diagnosis. Conclusions: The main reason for NIPT failure was the low ratio of cffDNA. Postponing the gestational weeks of blood collection may improve the success rate. Resampling and retesting upon informed consent in pregnant women who failed the first test could improve the success rate. For pregnant women who finally failed NIPT, it is suggested strengthening the genetic counseling, prenatal examination, and ultrasound evaluation, and carry out interventional prenatal diagnosis if necessary. [ABSTRACT FROM AUTHOR]

Accumulation of evidences suggested that excessive amounts of AChE and BuChE in the brain of AD patients at the different stage of AD, which could hydrolyze ACh and accelerated A β aggregation. To develop new "hidden" multifunctional agents through AChE/BuChE would be a promising strategy to treat AD. To this end, firstly, a series of chalcone derivatives with chelating property was designed and synthesized. The in vitro results showed that compound 3f indicated significant selective MAO-B inhibitory activity (IC 50 = 0.67 μM) and remarkable anti-inflammatory property. It also significantly inhibited self-induced A β 1-42 aggregation and showed remarkable neuroprotective effects on A β 25-35 -induced PC12 cell injury. Furthermore, compound 3f was a selective metal chelator and could inhibit Cu2+-induced A β 1-42 aggregation. Based on this, the carbamate fragment was introduced to compound 3f to obtain carbamate derivatives. The biological activity results exhibited that compound 4b showed good BBB permeability, good AChE inhibitory potency (IC 50 = 5.3 μM), moderate BuChE inhibitory potency (IC 50 = 12.4 μM), significant MAO-B inhibitory potency, anti-inflammation potency on LPS-induced BV-2 cells and neuroprotective effects on A β 25-35 -induced PC12 cell injury. Compared with 3f , compound 4b did not show obvious chelation property. Significantly, compound 4b could be activated by AChE/BuChE following inhibition of AChE/BuChE to liberate an active multifunctional chelator 3f , which was consistent with our original intention. More importantly, compounds 3f and 4b presented favorable ADME properties and good stability in artificial gastrointestinal fluid, blood plasma and rat liver microsomes. The in vivo results suggested that compound 4b (0.0195 μg/mL) could significantly improve dyskinesia and reaction capacity of the AlCl 3 -induced zebrafish AD model by increasing the level of ACh. Together our data suggest that compound 4b was a promising "hidden" multifunctional agent by AChE/BuChE, and this strategy deserved further development for the treatment of AD. [Display omitted] • Compound 3f was a promising multifunctional chelator. • Compound 4b was a hidden multifunctional prechelator. • Compound 4b could be activated to compound 3f by AChE/BuChE. • Compounds 3f and 4b presented favorable drug-likeness. • 4b could improve AlCl 3 -induced zebrafish AD model. [ABSTRACT FROM AUTHOR]

Soil and epikarst play an important role in the hydrological cycle in karst regions. This paper focuses on investigating the seasonal recharge and mean residence time (MRT) of soil water and epikarst water in a small karst catchment of southwest China. The deuterium contents in precipitation, creek, soil baseflow (direct recharge of the saturated soil water to the stream), epikarst spring, and soil waters were monitored weekly for two years, and MRT was calculated by an exponential model (EM) and a dispersion model (DM). The obvious seasonal variation of deuterium in rainfall was buffered in epikarst water, indicating sufficient water mixing. Soil baseflow contained less rainy-season rainwater than epikarst spring discharge, reflecting the retarded effect of soil thickness on rainwater recharge. MRTs of all water bodies were 41-71 weeks, and soils in the depression extended those of shallow groundwater. This demonstrated that the deep soil layer played an important role in karst hydrological processes in the study catchment. The creek was recharged mostly by rainfall through epikarst, indicating its crucial role in water circulation. These results showed epikarst had a strong water-holding capacity and also delayed water contact time with dolomite. [ABSTRACT FROM AUTHOR]

Background and Aim: Programmed death 1 (PD‐1) and programmed death ligand 1 (PD‐L1) inhibitors have transformed the treatment landscape of advanced hepatocellular carcinoma (HCC), but consistent responses are not observed in all patients, and prognostic biomarkers to guide treatment decisions are lacking. We aimed to evaluate the predictive value of PD‐L1 expression in advanced HCC patients treated with PD‐1/PD‐L1 inhibitors. Methods: A comprehensive search of PubMed, Embase, Web of Science, and the Cochrane Library was conducted. Studies comparing the objective response rate (ORR) and/or disease control rate (DCR) based on the tumor PD‐L1 status of HCC were included. Results: Eleven studies with 1,330 HCC patients treated with PD‐1/PD‐L1 inhibitors were included. Pooled odds ratio (OR) analysis demonstrated a significantly improved ORR in PD‐L1‐positive patients compared with PD‐L1‐negative patients (OR, 1.86, 95% CI, 1.35–2.55). Similar results were observed in the anti‐PD‐1 treatment (p < 0.001) and anti‐PD‐1/PD‐L1 monotherapy (p < 0.001) subgroups. The pooled ORRs in the PD‐L1‐positive and PD‐L1‐negative groups were 26% (95% CI, 20%–32%) and 18% (95% CI, 13%–22%), respectively. For DCR, the pooled OR analysis showed no significant difference between PD‐L1‐positive patients and PD‐L1‐negative patients (66% [95% CI, 55%–76%] vs. 69% [95% CI, 62%–76%]; OR, 0.92, 95% CI, 0.59–1.44). The results were consistent across the drug target and combination treatment subgroups. Conclusion: Positive PD‐L1 expression is associated with a better ORR in advanced HCC patients treated with anti‐PD‐1/PD‐L1‐based therapies. This feature can help to identify HCC patients who will benefit most from PD‐1/PD‐L1 inhibitors. [ABSTRACT FROM AUTHOR]

Introduction: Due to the high recurrence, the HCC prognosis remains poor. Yet, the biomarkers for predicting the recurrence of high‐risk patients are currently lacking. We aimed to develop a signature to predict the recurrence of HCC based on NKG2D ligands. Methods: The multivariate Cox proportional hazards regression was used to select recurrence‐related variables of NKG2D ligands in HCC patients from The Cancer Genome Atlas (TCGA). HCC patients from the OEP000321 dataset and Guilin cohort were used to validate the predictive signature. The mRNA expression of NKG2D ligands was measured by QRT‐PCR. Immunohistochemistry analysis of HCC tissue microarray samples was used to identify the expression of NKG2D ligands. Results: In this study, NKG2D ligands expression in the mRNA and protein level was both abnormally expressed in HCC and associated with recurrence‐free survival (RFS). Then, the recurrence‐related variables of NKG2D ligands in HCC were selected by the multivariate Cox proportional hazards regression. Among the eight NKG2D ligands, MICA (HR = 1.347; 95% CI = 1.012–1.793; p = 0.041), ULBP3 (HR = 0.453; 95% CI = 0.231–0.889; p = 0.021) and ULBP5 (HR = 3.617; 95% CI = 1.819–7.194; p < 0.001) were significantly correlated with RFS in the TCGA‐LIHC cohort. Then, the signature was constructed by the three NKG2D ligands. The predictive effectiveness of this signature was also validated in the OEP000321 dataset and Guilin cohort. Further, HCC patients were classified into low‐risk and high‐risk subgroups by the predictive score. Compared with the low‐risk group, the high‐risk group had poor RFS in both training and validation cohorts. Importantly, compared with the low‐risk patients with the G1‐G2 stage, the levels of infiltrated NK‐activated cells and NKG2D expression were both lower in the high‐risk patients. Conclusions: The signature based on MICA, ULBP3, and ULBP5 could predict HCC recurrence. [ABSTRACT FROM AUTHOR]

In regions with shallow soils underlain by fractured bedrock, hydrological processes of substrate are no longer only limited to soil layers. However, ecohydrological functions of bedrock fractures, especially those filled with different soil and regolith materials, have not been fully understood. In this study, we aimed to evaluate water transport and supplying capacities of the filled fractures through investigating hydraulic properties, and explore their dominant influencing factors. Three typical fractures, a vertical one filled with fine-textured soil (VSF), a vertical one filled with soil and regolith materials (VSRF), and a non-vertical one filled with coarse-textured soil (NSF) were selected from a large newly excavated trench on a karst hillslope of southwest China. Stratified samples of fracture fillings were collected to measure saturated hydraulic conductivity (K s ), water retention curves and basic physicochemical properties. Additionally, twenty soil profiles in different topographic locations in the same study area were also analyzed in order to support the results derived from the filled fractures. All fractures exhibited extremely high K s (87–149 mm h − 1 ) in surface soil (0–10 cm), which allowed rapid infiltration of rainwater into subsurface. Subsurface water transport was smooth when underlying fracture fillings were loamy with relatively high K s (about 10 mm h − 1 ) like in NSF, but was blocked when they were clayey with low K s (< 0.1 mm h − 1 ) like in VSF and VSRF. All fracture fillings had abilities to hold water and available water was the most in NSF, which provided an extra water source for plant growth in shallow soil regions. The ecohydrological functions of the filled fractures often depend on the properties and layering of fracture fillings, which was supported by those obtained from the twenty soil profiles. These results are helpful for better understanding of the ecohydrological processes and functions of fractures filled with different materials in karst regions. [ABSTRACT FROM AUTHOR]

Simple Summary: The lack of precision biomarkers hinders the development of individualized immunotherapy for esophageal cancer (ESCA) patients. The activation of WNT signaling has proved to be associated with the primary resistance to immunotherapy. Therefore, our study aims to develop efficient biomarkers based on WNT signaling to guide ESCA immunotherapy. In the TCGA cohort with 196 cases and our BJCH cohort with 95 cases, we successfully constructed an IGFBP1hiWNT3Alo signature and validated its correlation with the poor prognosis of ESCA patients. Moreover, in 2 GEO cohorts with a total of 68 cases and our BJIM cohort with 21 cases, we verified that IGFBP1hiWNT3Alo ESCA patients had a good response and prognosis with immunotherapy. Our findings indicate that the IGFBP1hiWNT3Alo signature was a potential immunotherapeutic biomarker for ESCA. PD-(L)1 inhibitor could improve the survival of locally advanced esophageal cancer (ESCA) patients, but we cannot tailor the treatment to common biomarkers. WNT signaling activation was associated with primary resistance to immunotherapy. In this study, we used our two clinical cohorts (BJCH n = 95, BJIM n = 21) and three public cohorts to evaluate and verify a new immunotherapeutic biomarker based on WNT signaling in ESCA patients. Our findings showed that WNT signaling-related genes stratified TCGA patients into Cluster 1, 2, and 3, among which, Cluster 3 had the worst prognosis. The most up- and down-regulated genes in Cluster 3 were IGFBP1 and WNT3A. Further analysis validated that IGFBP1hiWNT3Alo ESCA patients had significantly poor RFS and OS in the TCGA and BJCH cohorts. Interestingly, IGFBP1hiWNT3Alo patients had a good response and prognosis with immunotherapy in three independent cohorts, exhibiting better predictive value than PD-L1 expression (signature AUC = 0.750; PD-L1 AUC = 0.571). Moreover, IGFBP1hiWNT3Alo patients may benefit more from immunotherapy than standard treatment (p = 0.026). Immune cell infiltration analysis revealed a significant increase in DC infiltration in IGFBP1hiWNT3Alo patients post-immunotherapy (p = 0.022), which may enhance immune response. The IGFBP1hiWNT3Alo signature could predict patients who benefited from PD-(L)1 inhibitor treatment and may serve as a biomarker in ESCA. [ABSTRACT FROM AUTHOR]

A probabilistic method is presented to analyze the temperature and the maximum frequency for multicore processors based on consideration of workload variation, in this paper. Firstly, at the microarchitecture level, dynamic powers are modeled as the linear function of IPCs (instructions per cycle), and leakage powers are approximated as the linear function of temperature. Secondly, the microarchitecture-level hotspot temperatures of both active cores and inactive cores are derived as the linear functions of IPCs. The normal probabilistic distribution of hotspot temperatures is derived based on the assumption that IPCs of all cores follow the same normal distribution. Thirdly and lastly, the probabilistic distribution of the set of discrete frequencies is determined. It can be seen from the experimental results that hotspot temperatures of multicore processors are not deterministic and have significant variations, and the number of active cores and running frequency simultaneously determine the probabilistic distribution of hotspot temperatures. The number of active cores not only results in different probabilistic distribution of frequencies, but also leads to different probabilities for triggering DFS (dynamic frequency scaling). [ABSTRACT FROM AUTHOR]

• DOM molecular compositions in multi-interface runoffs were quantified by FT-ICR MS. • Soil-epikarst structures controlled the DOM quantity and molecular compositions. • High microbially-derived carbon was detected in epikarst flow. • Flow rate and discharge effected DOM quantity and quality during runoff process. • Soil thicknesses affected runoff DOM dynamics by impacting hydrological processes. Understanding the chemical composition, origin, and molecular structure of dissolved organic matter (DOM) in multi-interface runoff is essential for comprehending the fate of laterally transported DOM in complex soil-epikarst systems of karst hillslopes. Limited information, however, is available for the optical properties and molecular compositions of the transported OM in multiple runoff components on the karst hillslope in relation to land-uses and soil thicknesses. In this study, we conducted a study to observe the changes in the quantity and quality of DOM in multiple interface flow (surface, subsurface, and epikarst) during natural rainfall events in 2022 in karst hillslopes that are covered by different land uses (cropland and shrubland) and soil thicknesses (with mean depths of 66.0 cm for deeper soil and 35.4 cm for shallower soil) in the karst region of southwest China. chemcial compositions of runoff DOM were determined by optical analysis and microbial compositions in runoff were inferred with high-throughput sequencing. The results showed that the soil-epikarst structure was controlling the runoff DOM quantity and quality during rainfall events. A decrease in the aromaticity, humification, unsaturation, and oxidation degree and an increase in carbohydrate, aminosugars, protein, and lipid compounds were found from surface to epikarst flow, indicating that plant-and soil-derived carbon decreased, while the microbially-derived carbon increased. The results were further comfirmed by the higher bacterial richness and diversity, along with fungal diversity in the epikarst flow compared to other runoff components. The bio-labile protein materials (C2) were the most important component of runoff DOM output in karst hillslopes. In surface and subsurface flow, rainfall amount, runoff rate, and discharge significantly affected the DOM concentration and quality during rainfalls, indicating that the dynamics of DOM in runoff from karst hillslopes were predominantly influenced by hydrological processes. Furthermore, the runoff DOM quality in cropland was dominated by lower unsaturation and oxidation degrees and higher protein component, compared to those in shrubland. The compositions of DOM in runoff from hillslope plots with thicker soils were primarily characterized by microbially-derived materials. Our findings were conducive to understanding the mechanism governing the migration of DOM quality and quantity in discharge during multi-interface hydrological processes on karst hillslopes. [ABSTRACT FROM AUTHOR]

Low winter temperatures severely stress newly arriving insect species. Adaptive evolutionary changes in cold tolerance can facilitate their establishment in new environments. Ambrosia artemisiifolia, a noxious invasive plant, occurs throughout China. Ophraella communa, a biological control agent of A. artemisiifolia, mainly occurs in southern China. However, in 2012, it established populations in Beijing (39.98°N, 115.97°E) following introduction from Laibin (23.62°N, 109.37°E), implying cold adaptation. The mechanisms underlying its rapid evolution of cold tolerance remain unknown. We investigated the levels of cryoprotectants and energy reserves in adult O. communa from two latitudes. In high-latitude insects, we found high trehalose, proline, glycerol, total sugar, and lipid levels; five potential genes (Tret1a, Tret1b, Tret1-2, P5CS, and GST), responsible for regulating cold tolerance and involved in trehalose transport, proline biosynthesis, and glutathione S-transferase activation, were highly expressed. These hybridisation changes could facilitate cold temperature adaptation. We demonstrate the genetic basis underlying rapid adaptation of cold tolerance in O. communa, explaining its extension to higher latitudes. Thus, specialist herbivores can follow host plants by adapting to new temperature environments via rapid genetic evolution. [ABSTRACT FROM AUTHOR]

Purpose: Isotope-based root water uptake analysis usually involves cryogenic vacuum extraction (CVE) of water from soil and other water-holding materials, according to the assumption that no isotopic fractionation occurs during the related processes. Recently, a growing body of literature identified isotopic deviations that were caused by CVE. However, the isotopic deviations of water extracted from carbonate soils by CVE are undefined, which prohibits dependable utilization of stable water isotopes in CVE involved studies, especially in karst regions. Methods: Three types of water-holding material, weathered carbonate bedrock, typical karst soils that were kept intact or washed with diluted HCL thus with varying levels of carbonate content were oven-dried and spiked with various amounts of reference water. The recovery of known isotope values was tested in all rewetted samples by using one CVE system. Results: No significant differences were detected between the isotope values of the water extracted from the weathered carbonate bedrock and the input water. However, isotope values of water extracted from the soils were significantly more negative than the input water. Moreover, the magnitude of δD deviation was highly related to soil water content, while the magnitude of δ18O values was strongly dependent on the amount of carbonate present. Conclusions: Considering the isotopic deviations caused by CVE and the obstacles associated with the calibration process, the application of an isotope-based method that involves CVE needs to be adapted to the specific properties of karst regions. [ABSTRACT FROM AUTHOR]

Aim: A further understanding of relationship between soil and vegetation is a prerequisite for accelerating vegetation restoration in karst area. Remarkable achievements have been made at regional and individual plant scales, but research on the relationship between soil and vegetation is insufficient at the hillslope catena scale in karst area. Methods: Soils and vegetation were investigated along a toposequence of the dolomite peak-cluster depression catchment. Redundancy analysis (RDA) and structural equation modelling (SEM) were used to analysis topography, soil, and vegetation relationships. Results: The dolomite rocks displayed an evenly progressive karstification process. This led to an undeveloped underground karstic network that was unable to transport soil materials into ground. Soil materials accumulated at different topographic positions and formed continuous catena. Soil types showed a gradual transition in the form of: Entisol--Inceptisol--Semi-alfisol--Alfisol. The vegetation communities also corresponded to the change of different soil types along the slope, showing a gradual transition of herbs--herbs and shrubs--shrubs and trees--herbs and trees. RDA analysis displayed that the fine soil mass ratio was an important influencing factor for vegetation. SEM demonstrated that slope gradient directly impacted on soil nutrient stocks and indirectly affected vegetation diversity. Conclusions: A continuous soil catena pattern was developed along the toposequence. Parameters for nutrient stocks might be more suitable for assessing soil productivity and guiding vegetation restoration in karst regions than nutrient content parameters. Slope gradient, fine soil mass ratio and nutrient stocks were important factors affecting plant diversity in karst areas. [ABSTRACT FROM AUTHOR]

Ferulic acid (FA) is one of a common ingredients in Chinese herbal medicine. FA has the interesting property of promoting growth and improving meat quality in livestock, but the mechanism is not understood. This study evaluated both safety and mechanism of efficacy in zebrafish model. At 15 μg/mL or above, FA led to pericardial oedema and delayed growth in zebrafish embryos. Dietary FA promoted growth and feed assimilation in male adult zebrafish. Genes related to myogenic development (myod1, myog and myf5) were significantly upregulated by FA and muscle fibre width in skeletal muscle was increased. At 20 µg/g, FA significantly increased number of goblet cells in zebrafish intestinal tissue, and gut microbiota composition also changed. Based on 16s rRNA gene sequences, 20 μg/g FA decreased Firmicutes and increased Bacteroides. 20 μg/g FA also stimulated the expression of PPAR‐α, a gene associated with fat metabolism, and decreased the expression of PPAR‐β and PPAR‐γ. These gene expression changes were beneficial to fatty acid synthesis and metabolism and decreased fat deposition. Our overall results indicated that FA can be a safe growth promotor in fish particularly in skeletal muscles. [ABSTRACT FROM AUTHOR]

• Surface and bedrock topography are closely coupled in shallow soil-covered plot. • Soil moisture in thick soil plot is notably affected by the surface topography. • Runoff in thinner soil plot is remarkably affected by the bedrock topography. • Soil thickness is a critical factor in distinguishing hydrological processes. Topography plays a crucial role in predicting rainfall-runoff processes under climate change, as it affects the spatial distribution of water flow pathways. However, understanding the potential impact of high micro-topography heterogeneity on runoff generation remains challenging. We conducted high-resolution monitoring of soil moisture, instantaneous water table, and subsurface runoff in two 3D plots with different soil thicknesses (66 cm vs. 35 cm) in the karst region of southwest China. The topographic features were characterized by the soil thickness, relative elevation, and topographic wetness index obtained from a 1 × 1 m grid. The topography of the shallow-soil plot (SSP) exhibited a higher level of complexity, with a greater variability (approximately 80.0 %) in soil thickness compared to that of the deep-soil plot (DSP; approximately 61.5 %). Additionally, the SSP was prone to forming a micro-topography characterized by a combination of exposed bedrock and soil cover. In DSP, the variation in soil moisture was strongly controlled by surface topography, with elevation contributing to 52 % and 81 % of the explanation for the soil moisture at 30 cm and soil–bedrock interface, respectively. In SSP, the contribution of topography to the variation in soil moisture did not exceed 31 %. The controlling effect of topography on runoff is highlighted in SSP, with the contribution rates of surface and bedrock relative elevation reaching 79% and 97%, respectively.The weaker water storage capacity of the SSP resulted in a higher volume of subsurface runoff (161 t vs. 116 t) and frequency of runoff events (2248 vs. 1994) compared to the DSP. Accordingly, this study emphasizes that the soil–bedrock spatial heterogeneity will control the relationship between soil moisture, subsurface runoff, and terrain, which will contribute to providing a basis for flood prediction and model simulation in regions with complex topography. [ABSTRACT FROM AUTHOR]

Hypospadias is a common congenital abnormality of the penile. Abnormal regulation of critical genes involved in urethral development leads to hypospadias. We used the Rab25−/− mice and foreskin fibroblasts transfected with lentivirus in vitro and in vivo to investigate the role of Rab25 in hypospadias. The expression levels of various molecules in tissue samples and foreskin fibroblasts were confirmed using molecular biology methods (western blotting, PCR, immunohistochemistry, etc.). A scanning electron microscope (SEM) was used to visualize the external morphology of genital tubercles (GTs) of gestation day (GD) 18.5 male wild-type (WT) and Rab25 −/− mice. An expanded distal cleft and V-shaped urethral opening were observed in GD 18.5 Rab25 −/− mice. We demonstrated that Rab25 mediated hypospadias through the β1 integrin/EGFR pathway. In addition, silencing Rab25 inhibited cell proliferation and migration and promoted apoptosis in the foreskin fibroblasts; Ki-67- and TUNEL-positive cells were mainly concentrated near the urethral seam. These findings suggest that Rab25 plays an essential role in hypospadias by activation of β1 integrin/EGFR pathway, and Rab25 is a critical mediator of urethral seam formation in GD18.5 male fetal mice. • Abnormal expression of Rab25 leads to hypospadias by activating the β1 integrin/EGFR signaling pathway. • Silencing Rab25 inhibited proliferation and migration and promoted apoptosis in foreskin fibroblasts; Ki-67- and TUNEL-positive cells were mainly concentrated near the urethral seam. [ABSTRACT FROM AUTHOR]

• Rock surface flow accelerated the rill erosion of excavated slope. • Soil and water loss of SRS and KRS were higher than the bare slope. • Rills below rock outcrops didn't develop into a rill network after formation. • Effects of rock outcrops on the rill morphological characteristics and hydrodynamic mechanisms were investigated. Rock surface flow is the secondary distribution of precipitation and inflow on the rock surface, an essential runoff generation mode in karst areas. The effects of rock surface flow on soil erosion in karst regions cannot be ignored. However, its impact on rill erosion in karst slopes remains unclear. The objectives of this study were to investigate the impact of rock surface flow on rill erosion, rill morphological characteristics, rill flow hydraulic characteristics, and hydrodynamic mechanisms. A field runoff plot (3 m long, 1 m wide and 0.3 m deep) with three inflow rates (2, 3, and 4 L/min) was subjected to runoff simulation experiments under two typical rock surface morphologies in karst areas: smooth rock surface (SRS) and karren rock surface (KRS), with bare slope (BS) as the control group. The results revealed that rock surface flow aggravated the soil and water loss of the excavated slope. Compared to BS, the runoff yield for SRS and KRS increased by 81.49 % and 61.91 %, respectively. Meanwhile, the soil loss of SRS and KRS were 2.50 times and 5.56 times greater. The rills below the rock outcrops didn't develop into a rill network after formation, owing to the rock surface morphology. Rill depth was the best indicator of rill morphology for evaluating rill erosion on slopes below rock outcrops. The Reynolds number and Darcy–Weisbach resistance coefficient were the optimal hydraulic parameters to predict the rill erosion of the SRS and KRS, respectively. At the same time, the runoff power and flow shear stress were the best hydrodynamic parameters to describe the rill erosion mechanism of SRS and KRS. These results provide a scientific basis for further understanding the mechanism of soil erosion on karst slopes and for preventing soil erosion on karst slopes in mining areas. [ABSTRACT FROM AUTHOR]

Fatty liver disease associated with metabolic dysfunction is of increasing concern in mainland China, the world's most populous country. The incidence of fatty liver disease is highest in China, surpassing the incidence in European countries and the USA. An international consensus panel recently published an influential report recommending a novel definition of fatty liver disease associated with metabolic dysfunction. This recommendation includes a switch in name from non-alcoholic fatty liver disease (NAFLD) to metabolic (dysfunction)-associated fatty liver disease (MAFLD) and adoption of a set of positive criteria for disease diagnosis that are independent of alcohol intake or other liver diseases. Given the unique importance of this proposal, the Chinese Society of Hepatology (CSH) invited leading hepatologists and gastroenterologists representing their respective provinces and cities to reach consensus on alternative definitions for fatty liver disease from a national perspective. The CSH endorses the proposed change from NAFLD to MAFLD (supported by 95.45% of participants). We expect that the new definition will result in substantial improvements in health care for patients and advance disease awareness, public health policy, and political, scientific and funding outcomes for MAFLD in China. [ABSTRACT FROM AUTHOR]

Vegetation restoration has been proposed as an effective strategy for increasing soil organic carbon (SOC) sequestration. However, the responses of SOC to managed and natural vegetation restoration strategies at a large scale are poorly understood due to the varying SOC components and changing climatic conditions. Here, we measured bulk SOC, particulate organic carbon (POC), and mineral-associated organic carbon (MOC) after 15 years of vegetation restoration along an elevation gradient with a corresponding temperature gradient in the calcareous soils of karst region, Southwest China. We compared managed plantation forest and naturally recovered shrubland vegetation restoration strategies, using cropland and mature forest as references. Overall, we found that the SOC and POC densities in both plantation forest and shrubland were significantly higher than in the cropland but lower than in the mature forest. There were no significant differences in the SOC pool between the plantation forest and shrubland. Furthermore, the relative changes in the SOC and POC densities increased with increasing mean annual temperature in the plantation forest and shrubland. Our results showed that both vegetation restoration strategies, characterized by higher soil microbial abundance and exchangeable Ca concentration, were beneficial to POC but not MOC accumulation, and sufficiently compensated SOC decomposition at lower elevation with higher MAT. Our results highlight the potential of both vegetation restoration strategies for promoting SOC accumulation in warmer karst regions and emphasize the necessity to understand soil carbon stabilization mechanisms in calcareous soils. Unlabelled Image • Managed and natural vegetation restoration were compared along a climatic gradient. • Both vegetation restoration strategies increased soil carbon stocks in warmer regions. • Higher temperature shifted soil microbial community structure. • Restored vegetation had higher microbial abundance and calcium than cropland. • Microbial abundance and calcium negated effect of temperature on SOC decomposition. [ABSTRACT FROM AUTHOR]

Background: Since it's a challenging task to precisely predict the prognosis of patients with hepatocellular carcinoma (HCC). We developed a nomogram based on a novel indicator GMWG [(Geometric Mean of gamma-glutamyltranspeptidase (GGT) and white blood cell (WBC)] and explored its potential in the prognosis for HCC patients.Methods: The patients enrolled in this study were randomly assigned to training and validation cohorts. And we performed the Least Absolute Shrinkage and Selection Operator proportional hazards model (LASSO Cox) model with clinical characteristics, serum indexes, and novel GMWG. Multivariate analysis was performed to build a nomogram. The performance of the nomogram was evaluated by C-index, the area under the receiver operating characteristic curve (AUC), and the calibration curve. Kaplan-Meier curves showed discrimination of the nomogram. Clinical utility was assessed by decision curve analysis (DCA). The discrimination ability of the nomogram was determined by the net reclassification index (NRI).Results: The geometric mean of GGT and white WBC count (GMWG), neutrophil to lymphocyte ratio (NLR), and tumor size were significantly associated with the overall survival (OS). The variables above were used to develop the nomogram. The indexes of nomogram were 0.70 and 071 in the training or validation cohort, respectively. AUC of 1-, 3- and 5-year OS showed satisfactory accuracy as well. The calibration curve showed agreement between the ideal and predicted values. Kaplan-Meier curves based on the overall survival (OS) and disease-free survival (DFS) showed significant differences between nomogram predictive low and high groups. DCA showed clinical utilities while NRI showed discrimination ability in both training or validation cohort.Conclusions: GMWG might be a potential prognostic indicator for patients with HCC. The nomogram containing GMWG also showed satisfaction prediction capacity. [ABSTRACT FROM AUTHOR]

Concentrations of heavy metals continue to increase in soil environments as a result of both anthropogenic activities and natural processes. Cadmium (Cd) is one of the most toxic heavy metals and poses health risks to both humans and the ecosystem. Herein, we explore the impacts of Cd on a soil–plant system composed of oilseed rapes (Brassica napus and Brassica juncea) and bacteria. The results showed that Cd accumulation within tissues of two species of oilseed rapes enhanced with increasing concentrations of Cd in soils, and Cd treatment decreased their chlorophyll content and suppressed rapeseeds growth. Meanwhile, Cd stress induced the changes of antioxidative enzymes activities of both B. napus and B. juncea. Response to Cd of bacterial community was similar in soil-two species of oilseed rapes system. The impact of Cd on the bacterial communities of soils was greater than bacterial communities of plants (phyllosphere and endophyte). The α-diversity of bacterial community in soils declined significantly under higher Cd concentration (30 mg/kg). In addition, soil bacterial communities composition and structure were altered in the presence of higher Cd concentration. Meanwhile, the bacterial communities of bulk soils were significantly correlated with Cd, while the variation of rhizosphere soils bacterial communities were markedly correlated with Cd and other environmental factors of both soils and plants. These results suggested that Cd could affect both the growth of plants and the indigenous bacterial community in soil–plant system, which might further change ecosystem functions in soils. [ABSTRACT FROM AUTHOR]

• Soil-rock interfaces are identified by using electrical resistivity tomography. • Soil probe measurements are likely to underestimate soil thickness in karst areas. • Soil thickness/stock in karst forests decreases from high to low latitudes. • The rock outcrop coverage rate explains 52 % of the variation in soil thickness. Soils provide storage space for nutrients and water, which governs many hydrological processes and functions in the natural ecosystems. Due to the complex soil-rock structures and localized climate, soil thickness and stock vary distinctly in different karst areas in southwest China. The difficulties of soil detection and the non-transparent underground soil-rock structures limit a deeper understanding of the spatial distribution of soils and their ecological functions. In this study, we employed electrical resistivity tomography (ERT) combined with soil probes to detect the spatial distribution of soils on hillslopes in karst forests in southwest China. The ERT surveys were conducted at six sites with 19 plots (20 × 30 m2) along latitudinal gradients. The results show that the ERT method performs well in visualizing the complex soil–bedrock interfaces and patchy distribution of soils in karst hillslopes, with remarkable consistency with the observed soil thickness and rock outcrops. Soil probes often hit rocks in soils (which we call a "rock barrier effect"), resulting in an underestimation of the mean soil thickness within the one-meter exploration depth by ∼0.18 m. This indicates that soil stock estimates derived from soil probes may be obviously underestimated in karst areas where the rock barrier effects are widespread. Meanwhile, the concept of equivalent soil thickness is proposed to remove the impact of scattered bedrock on soil stock estimation. For the six selected sites, the ERT-inferred mean soil thickness, equivalent soil thickness, and stock are 0.86 m, 0.60 m, and 0.10 m3/m3 respectively, with a trend of decreasing from high to low latitudes. Moreover, the rock outcrop coverage rate explains 52 % (60 %) of the variation in soil thickness (stock), followed by the annual mean temperature. This study emphasizes the importance of considering bedrock topography and its distribution in improving the detection of soil distribution, and the implications of the findings in this study are perhaps most profound for soil thickness-related soil erosion, soil water storage, and carbon storage in karst critical zones. [ABSTRACT FROM AUTHOR]

Carbonate landscapes make up one-fifth of the terrestrial land area, a better understanding of the coupling relationship between the soil–epikarst form and hydrological function is imperative for hydrology and landscape evolution modeling. In this study, we monitored a total of 158 rainfall-runoff events on a karst slope between 2019/4 and 2022/5 in southwest China, while simultaneously examining the soil–epikarst architecture (924 pairs of soil thickness and epikarst weathering degree). The results indicated that soil thickness increased with the underlying epikarst weathering degree, and soil thickness was positively correlated with epikarst thickness (P < 0. 001). Additionally, a significant positive relationship (P < 0. 001) was observed between surface runoff (SR) and soil thickness, as well as a significant negative relationship (P = 0. 0018) between subsurface runoff (SSR) and soil thickness. These findings imply the dominance of SR and SSR (under normal rainfall conditions) in runoff plots with deep soil layers and thin soil layers, respectively. The soil thickness threshold at which the hillslope discharge shifted from being SSR-dominated to SR-dominated was approximately 50 c m. Nonetheless, a positive relationship was found between SR and SSR under extreme rainfall events, indicating the establishment of hydrological connectivity between the surface and subsurface. Moreover, the hillslope discharge when the rainfall depth is lower than 50 mm is primarily composed of either SR or SSR from different plots. In other words, the hillslope discharge is typically influenced by both SR and SSR when the rainfall depth exceeds 50 mm. We finally proposed a positive feedback loop among soil thickness, epikarst weathering degree, and the hydrological function of the soil–epikarst system (water storage and release). These findings enhance our understanding of the complex interactive relationships in hillslope hydrology by illuminating the physical links between critical zone structures and hydrological processes on the karst slope. [Display omitted] • Soil thickness increased with weathering degree of epikarst. • SR dominated deep soil sites under normal rainfall conditions. • SSR dominated thin soil sites under normal rainfall conditions. • SR had a positive relationship with SSR under extreme rainfall events. • Bedrock weathering degree, soil thickness, and SR form a positive feedback loop. [ABSTRACT FROM AUTHOR]