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Ecological restoration projects have significantly increased global vegetation cover and reduced soil erosion. However, it is very challenging to clarify the complex soil erosion mechanisms of limestone and dolomite in the southwest karst region and to identify the key factors affecting erosion. The study site has a subtropical monsoon climate with precipitation concentrated during the rainy season from May to September. In this study, four plantation restoration measures with a recovery time of approximately 16 years were selected, which included arbor forest, orchard, grassland, and cropland (control). Soil physical–chemical properties and soil erodibility K values were used to evaluate the soil erosion characteristics. The results showed that both limestone and dolomite exhibited lower soil bulk density as well as higher capillary porosity, and soil water‐stable aggregates after revegetation. The limestone and dolomite K values were reduced by 12%–15% and 15%–17%, respectively. However, the K value of limestone was 17.9% higher than that of dolomite, indicating that dolomite exhibited a higher stability. Through redundancy analysis and structural equation modeling, revegetation was found to reduce soil erosion by influencing the soil particle composition. The silt was the key factor influencing soil erosion, accounting for 84.4% and 78.2% of the variation in the limestone and dolomite K values, respectively. These findings suggest that vegetation restoration enhances soil erosion resistance; however, the effectiveness of restoration is controlled by the lithology in the southwest karst region. These findings provide a reference for soil and water management and vegetation restoration. [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]

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]

Water ages in plant transpiration reveal important processes of water dynamics in soil‐plant‐atmosphere continuum, which is regulated by water variability and availability in both precipitation inputs and root zone. However, the impacts of climate patterns and rooting depth on water age dynamics in transpiration are inadequately investigated. In this study, variations in root‐zone water replenishment are estimated based on stable isotope compositions of precipitation and plant xylem water, and a piecewise linear mixing water age model is employed to quantify water ages in plant transpiration under five different climates. The results show that water ages in transpiration are very dynamic in all climates with a range between 1 and 229 days. Water replenishments in the root‐zone reveal whether and how much precipitation enters the root zone. Climate patterns control median (mean) water age in plant transpiration but modified by rooting depth. In wet climates, plants mainly rely on water source that originates from precipitation in the current month (accounting for about 60% on average of their water sources), while plants in dry climates largely rely on water source that originates from precipitation fallen on previous months/seasons. These indicate that climate has profound impacts on plant water source by regulating precipitation inputs, root zone water storage and residence time, and evapotranspiration. Despite the limitations of this study, our study provides an alternative way to reveal the precipitation partitioning in root‐zone and seasonal changes in plant water use of precipitation, which highlights different vegetation responses to water variability between climate types. Key Points: Stable isotopes reveal how precipitation is partitioned (replenishment/bypass) in the root‐zoneWater ages in plant transpiration are estimated as a function of root‐zone water replenishmentClimate patterns and rooting depth control median (mean) water age in plant transpiration [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]

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]

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]

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]

Common ragweed (Ambrosia artemisiifolia) is a notorious invasive weed that has spread across most temperate regions of the world. The beetle (Ophraella communa) is considered to be an effective control agent against A. artemisiifolia. As an oligophagous insect, its olfactory system is extremely important for host seeking in the wild. To the best of our knowledge, there is no report on the molecular mechanisms underlying olfaction recognition in this beetle. Hence, in this study, we characterized the odorant receptor co‐receptor of O. communa and named it as 'OcomORco'. Real‐time quantitative PCR (qRT‐PCR) showed that, compared to the control treatment, RNA interference (RNAi) strongly reduced the expression of OcomORco by 89% in male and 90% in female beetles. Electroantennogram assay showed that the antennal response of both male and female beetles to four volatiles of A. artemisiifolia was significantly reduced. The injected male or female beetles lost their preference for plant leaves as observed in the behavioural tests. In addition, disruption of the expression of OcomORco resulted in a reduction of oviposition, while there was no difference in larval hatching rate between control and knockdown females. We demonstrated that OcomORco plays a vital role in olfactory perception and host search in O. communa, and it is involved in oviposition in an indirect way. [ABSTRACT FROM AUTHOR]

Abstract: Daily actual evapotranspiration (AET) and seasonal AET values are of great practical importance in the management of regional water resources and hydrological modelling. Remotely sensed AET models and Landsat satellite images have been used widely in producing AET estimates at the field scale. However, the lack of validation at a high spatial frequency under different soil water conditions and vegetation coverages limits their operational applications. To assess the accuracies of remote sensing‐based AET in an oasis‐desert region, a total of 59 local‐scale daily AET time series, simulated using HYDRUS‐1D calibrated with soil moisture profiles, were used as ground truth values. Of 59 sampling sites, 31 sites were located in the oasis subarea and 28 sites were located in the desert subarea. Additionally, the locally validated mapping evapotranspiration at high resolution with internalized calibration surface energy balance model was employed to estimate instantaneous AET values in the area containing all 59 of the sampling sites using seven Landsat subimages acquired from June 5 to August 24 in 2011. Daily AET was obtained using extrapolation and interpolation methods with the instantaneous AET maps. Compared against HYDRUS‐1D, the remote sensing‐based method produced reasonably similar daily AET values for the oasis sites, while no correlation was observed for daily AET estimated using these two methods for the desert sites. Nevertheless, a reasonable monthly AET could be estimated. The correlation analysis between HYDRUS‐1D‐simulated and remote sensing‐estimated monthly AET values showed relative root‐mean‐square error values of 15.1%, 12.1%, and 12.3% for June, July, and August, respectively. The root mean square error of the summer AET was 10.0%. Overall, remotely sensed models can provide reasonable monthly and seasonal AET estimates based on periodic snapshots from Landsat images in this arid oasis‐desert region. [ABSTRACT FROM AUTHOR]

Core Ideas: Macropores and cracks are preferential channels in karst depression and downslope locationsHeterogeneity of soil property results in finger flow in karst mid‐ and upslope locationsHigh Ks and soil layering weaken preferential flow in mid‐ and upslope locationsPreferential flow degree and infiltration rate can be independent in karst regions In karst regions, soil architecture varies along topographical locations, resulting in marked differences in infiltration rates. However, the relationship between soil architecture and preferential flow (PF) is still unclear. In this study, dye tracing was used to investigate PF and the dominant effects of five types of soil architecture in a small karst catchment. These soil architectures included deep clay soil in farmland (CSF) and deep clay soil in shrubland (CSS) in the depression; shallow clay soil with minimally weathered, slanted bedrock on downslope locations (CSWD); shallow sandy loam soil with highly weathered bedrock on midslope locations (SLSM); and sandy loam soil with rock fragments on upslope locations (SLSU). The results showed that macropores and cracks were the major channels that resulted in a high degree of PF in depressions and downslope locations. Preferential flow also continued along the rock–soil interface in the downslope locations. Finger flow mainly appeared in mid‐ and upslope locations, and cracks mainly appeared in the surface soil layer. However, down‐ and upslope locations showed lower PF. We observed that PF might not contribute to the different infiltration rates in different topographical locations. Tillage in depressions damages macropores, thereby minimizing vertical percolation. The high saturated hydraulic conductivity (Ks) of the soil matrix covered the development of PF in the mid‐ and upslope locations, and the decrease in Ks weakened the formation of PF as a result of heterogeneity of soil properties. These findings demonstrate that infiltration‐excess runoff may occur in depressions and downslope locations and that saturation‐excess runoff may occur in mid‐ and upslope locations. [ABSTRACT FROM AUTHOR]

Epikarst exerts a strong control on run-off generation in karst regions, but it is still unclear in karst regions. Our study aimed to demonstrate the effect of epikarst on near-surface hydrological processes in a subtropical cockpit karst region of southwest China, using plot-scale rainfall simulation experiments with different rainfall intensities (low and high) and antecedent moisture conditions (dry and wet). A trench excavated to the epikarst lower boundary allowed identification of flow pathways in the entire soil-epikarst architecture system, thus facilitating the water balance calculations using a conceptual model with the assumption of a two-stage hydrological evolution. More than 70% of the total rainfall water moved vertically through the shallow soil layer and then was redistributed by the epikarst as subsurface flow occurring on the soil-epikarst interface, depression filling on epikarst surface, water held by epikarst and deep percolation. Epikarst water regulation capacity, defined as the sum of depression filling on epikarst surface, water held by epikarst, epikarst seepage flow and deep percolation, was 58 mm (wet antecedent condition) and 223 mm (dry antecedent condition). Total run-off from the soil-epikarst system was dominated by saturated subsurface flow showing a threshold process controlled by epikarst storage capacity (storing as much as 181 mm of rainfall water under dry antecedent condition). Our study proved that despite the epikarst being relatively poorly developed and covered by a soil mantle, it still exerted a strong influence on near-surface hydrological processes and thus should be adequately considered in future modelling of water recharge and depletion dynamics in this integrated soil-epikarst system. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Reliable assessment of the spatial distribution of soil erosion is important for making land management decisions, but it has not been thoroughly evaluated in karst geo-environments. The objective of this study was to modify a physically based, spatially distributed erosion model, the revised Morgan, Morgan and Finney (RMMF) model, to estimate the superficial (as opposed to subsurface creep) soil erosion rates and their spatial patterns in a 1022 ha karst catchment in northwest Guangxi, China. Model parameters were calculated using local data in a raster geographic information system (GIS) framework. The cumulative runoff on each grid cell, as an input to the RMMF model for erosion computations, was computed using a combined flow algorithm that allowed for flow into multiple cells with a transfer grid considering infiltration and runoff seepage to the subsurface. The predicted spatial distributions of soil erosion rates were analyzed relative to land uses and slope zones. Results showed that the simulated effective runoff and annual soil erosion rates of hillslopes agreed well with the field observations and previous quantified redistribution rates with caesium-137 (137Cs). The estimated average effective runoff and annual erosion rate on hillslopes of the study catchment were 18 mm and 0.27 Mg ha−1 yr−1 during 2006-2007. Human disturbances played an important role in accelerating soil erosion rates with the average values ranged from 0.1 to 3.02 Mg ha−1 yr−1 for different land uses. The study indicated that the modified model was effective to predict superficial soil erosion rates in karst regions and the spatial distribution results could provide useful information for developing local soil and water conservation plans. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article examines the variations of surface soil moisture content in a karst depression area in southwest China during the dry and rainy seasons in 2005. It finds that the variability of surface soil moisture was relatively higher in the dry season than in the rainy season, while on the other hand, the mean soil moisture content was higher during the rainy season, especially after heavy rainfall. It also identifies land use types, bare-rock ratio, and soil organic matter as major factors affecting soil moisture variability in the karst ecosystem.

Summary The tumour-associated antigen mucin 1 (MUC1) is a multifunctional protein involved in protection of mucous membranes, signal transduction, and modulation of the immune system. More than 70% of cancers overexpress MUC1, making MUC1 a potential target for immunotherapy. In the present study, MUC1 transgenic mice were crossed with syngeneic strains that express the polyomavirus middle-T oncogene (PyMT) driven by the mouse mammary tumour virus promoter long-terminal repeat (MMTV-LTR). The resultant breed (MMT mice) developed spontaneous MUC1-expressing mammary carcinomas with 100% penetrance at 8–15 weeks of age. As found in human breast cancer, the mammary carcinoma in MMT mice arose in multiple stages. Immunization with fusions of dendritic cells and MUC1-positive tumour cells (FC/MUC1) induced MUC1-specific immune responses that blocked or delayed the development of spontaneous breast carcinomas. In contrast, there was no delay of tumour development in MMT mice immunized with irradiated MC38/MUC1 tumour cells. The efficacy of fusion cells was closely correlated with the timing of initial immunization. Immunization with FC/MUC1 initiated in MMT mice at < 1, 1–2 and 2–3 months of age rendered 33, 5 and 0% of mice free of tumour, respectively, up to 6 months. Whereas mice immunized in the later stage of tumour development succumbed to their disease, immunization resulted in control of tumour progression and prolongation of life. These results indicate that immunization with FC/MUC1 can generate an anti-MUC1 response that is sufficient to delay the development of spontaneous mammary carcinomas and control tumour progression in MMT mice. [ABSTRACT FROM AUTHOR]