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Inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ) is one of important kinases in inflammation to phosphorylate inhibitor of nuclear factor kappa-B (IκBα) and then activate nuclear factor kappa-B (NF-κB). Inhibition of IKKβ has been a therapeutic strategy for inflammatory and autoimmune diseases. Here we report that IKKβ is constitutively activated in healthy donors and healthy IkkβC46A (cysteine 46 mutated to alanine) knock-in mice although they possess intensive IKKβ–IκBα–NF-κB signaling activation. These indicate that IKKβ activation probably plays homeostatic role instead of causing inflammation. Compared to IkkβWT littermates, lipopolysaccharides (LPS) could induce high mortality rate in IkkβC46A mice which is correlated to breaking the homeostasis by intensively activating p-IκBα–NF-κB signaling and inhibiting phosphorylation of 5ʹ adenosine monophosphate-activated protein kinase (p-AMPK) expression. We then demonstrated that IKKβ kinase domain (KD) phosphorylates AMPKα1 via interacting with residues Thr183, Ser184, and Thr388, while IKKβ helix–loop–helix motifs is essential to phosphorylate IκBα according to the previous reports. Kinase assay further demonstrated that IKKβ simultaneously catalyzes phosphorylation of AMPK and IκBα to mediate homeostasis. Accordingly, activation of AMPK rather than inhibition of IKKβ could substantially rescue LPS-induced mortality in IkkβC46A mice by rebuilding the homeostasis. We conclude that IKKβ activates AMPK to restrict inflammation and IKKβ mediates homeostatic function in inflammation via competitively phosphorylating AMPK and IκBα.

Flash flood disaster, with strong suddenness and tremendous destructiveness, is one of the most severe natural disasters in China that seriously threaten the lives and property safety of people and social development. Owing to the complex terrain and limited rainfall and runoff monitoring gauges, it is arduous to effectively prevent and control flash flood disasters in small-sized and medium-sized hilly watersheds. Identifying rainfall threshold, critical discharge and warning periods for flash flood, is critical in disaster prevention in such regions. This study adopted two approaches, the entropy-based decision approach and the hydrological model approach in calculating rainfall thresholds under different antecedent moisture condition (AMC). In particular, the entropy-based decision approach was improved, by using the Frank copula to calculate the multivariate joint distribution of the cumulative rainfall and the corresponding peak discharge. These two approaches were validated in a typical basin, located in the Pearl River Delta in South China that is characterized by frequently heavy rainfall and floods in the monsoon. Results showed that both approaches have the ability to quantify rainfall thresholds. Relatively, the Bayesian method exhibited higher rainfall thresholds, comparing to the other methods. In particular, for AMC I, the utility-entropy risk function method (with λ = 1) exhibited the best-applied practicable forecast lead time of 2.0 h; as for AMC II, the two methods showed the same forecast lead time of 1.5 h, and for AMC III, the hydrological model-based approach showed an optimal forecast lead time of 6.0 h. Meanwhile, the entropy-based approach exhibited the same performance as hydrological modeling approaches, indicating that this method is practicable in flood forecasting. The results would be helpful for floods prevention and mitigation in such small-sized and medium-sized hilly watersheds.

Regulating the surface properties of catalysts to control the selectivity of a reaction is a fascinating approach. Bulk polymeric carbon nitride exhibits a poor N-phenylhydroxylamine yield in nitrobenzene reduction reaction mainly due to the uncontrollable condensation side reactions. Thus, adjusting the structure of the catalyst was key to solving the above issue. Herein, –OH groups-modified polymeric carbon nitride was prepared via a simple hydrothermal treatment. With the introduced –OH groups replacing the terminal amino groups (–NH2) at the surface of the polymeric carbon nitride, a 3-fold increase in reaction rate was achieved, along with a high selectivity toward N-phenylhydroxylamine (ca. 80%). The introduced –OH group was found to be beneficial to the adsorption of the nitrobenzene, based on the density functional theory (DFT) calculation. It could also lower the recombination rate of photoinduced electron–hole pairs, which would accelerate the photocatalytic oxidation of isopropanol and supply more protons to participate in the hydrogen-transfer process. Moreover, the elevated conduction band position after –OH modification would provide high energetic photogenerated electrons to promote the reduction of nitrobenzene. These are all important to guarantee the highly selective production of N-phenylhydroxylamine. This paper not only provides a simple and green approach for the modification of polymeric carbon nitride toward an efficient photocatalyst, but also sheds light on the further study of the selective hydrogenation.

This study investigates the relationships between water partitioning, climate and vegetation dynamics, and their influencing factors, using a method combining scenario analysis and a modified Choudhury's formula that considers climate and vegetation seasonality. Comparing the results in ten major catchments in southwestern China with similar climate and vegetation but drastically different topography, shows that the climate and vegetation seasonality jointly control the variance in the catchment parameter n of the Choudhury's formula (R

Two-way feedbacks exist between water-stressed vegetation and agricultural drought. Previous studies have focused mainly on the responses of vegetation to agricultural droughts but rarely on those of agricultural droughts to vegetation. Based on a new drought index (AgDI) that incorporates dynamic climatic and vegetation information, this study evaluated the impacts of climate and vegetation variabilities on agricultural droughts in 20 catchments in southwestern China, a region frequently hit by droughts. Results showed that the drought-stressed vegetation tended to alleviate agricultural droughts, and the drought-alleviating ability of vegetation was affected by vegetation types and the magnitudes of the changes in climate. Compared to other types of vegetation, the natural forest generally has a greater ability to affect agricultural drought. Overall, the relative contribution (mean of 29.9 ± 24.6%) of changes in vegetation to agricultural drought was at least comparable to those of the changes in potential evapotranspiration (mean of 14.4 ± 12.7%). Results also showed that even though vegetation has the ability to alleviate agricultural droughts, the changes in agricultural droughts were still dominated by climate changes, especially precipitation (mean relative contribution of 55.7 ± 24.2%).

Inhibitor of nuclear factor kappa-B kinase subunit beta (IKK

Spatial distribution of soil moisture (SM) is a prerequisite for research and management of agriculture and ecology. However, it is still a challenge to retrieve SM data in highly heterogeneous landscapes. By investigating environmental factors (soil, vegetation and topography) and comparing different remote sensing sources (Landsat-8, Radarsat-2, ASTER Global Digital Elevation Model (DEM) V002 (ASTGTM2), unmanned aerial vehicle (UAV)) for karst mountainous catchments of southwest China, this study identified key controlling factors on the spatial distribution of SM and built a remote sensing model for SM estimation in highly heterogeneous landscapes. Results showed that vegetation type (35.7%), aspect (7.7%), height index (4.2%), soil bulk density (3.3%), soil total nitrogen (3.1%), aspect interact with vegetation type (3.4%) and soil total phosphorous (1.3%) totally explained 58.8% of the SM variability. The correlations between SM and topographic derivatives varied with DEM resolutions (1–50 m), and generally reached their highest values at 7 m for height index, slope gradient, and aspect, 16 m for flow accumulation and topographic wetness index, and 43 m for curvature. Partial least-squares regression analysis showed that optical and infrared bands from Landsat-8 and topographic derivatives from UAV photogrammetry DEM were more strongly correlated with SM than other datasets. An empirical model (SM = 9.27 ∗ 10−2HI − 1.82 ∗ 10−5B5 + 0.519) with only height index and B5 band from Landsat-8 as inputs is proposed, as it shows acceptable performance (R2 = 0.36; RMSE = 0.076). The results of this study provide useful information for SM remote sensing in karst mountainous area and similar heterogeneous landscapes.

The critical zone (CZ) represents the intersection of the biosphere with the atmosphere, hydrosphere and lithosphere. Understanding the hydrological processes and human impact factors on the CZ is fundamental to sustainable water resources management for agroforestry. Transpiration ( T ) is an important component of terrestrial evapotranspiration (ET), and understanding the time lag (TL) between vegetation transpiration and meteorological factors can improve our knowledge of the mechanisms of vegetation adaptability to a changing environment. However, the controlling factors on the TL remain poorly understood. Therefore, the objective of this study is identifying the temporal dynamics of key controlling factors on the TL, using a typical deciduous broad-leaved tree species ( Zenia insigins Chun) of CZ in subtropical humid karst regions. This species is used as an example to explore the characteristics of the TL between SF (sap flow) and hydro-meteorological forcing. Sap flow in these 6 trees was monitored using the thermal dissipation probes (TDP). Results showed that: (1) the peak of diurnal sap flow generally lagged behind PAR but preceded Ta (air temperature), RH (relative humidity) and VPD (vapor pressure deficit), with the mean TL of −67.4 min (PAR), 90.5 min ( Ta ), 91.6 min (RH) and 92.9 min (VPD), respectively; (2) TL had no significant relationships with the daily mean meteorological factors and soil moisture, but was highly ( R 2>0.66) correlated to CRs (changing rates of meteorological factors) in the morning; (3) At seasonal scale, the sap flow rate and TL both were controlled by the seasonality of precipitation and temperature. Overall, the seasonality of the TL was caused by plants’ high water loss and strongly active physiological response in hot seasons, leading to close stomata earlier than in cold seasons; (4) The reason why CRs proposed can explain the TL better than mean values of metrological factors is that the CRs considered the distribution and change processes of metrological factors in the daytime. This study may be helpful for understanding the physiological response of vegetation to climatic change, and may be useful for constructing models to simulate transpiration processes more accurately during a day.

Vegetation restoration was implemented to control soil erosion in the karst regions of southwest China. It is essential to assess the soil function and quality scientifically during this process and to adopt suitable management practices for this area. However, few studies have been conducted to comprehensively evaluate the effect of vegetation restoration on soil quality in this severely eroded karst area. By taking 302 soil samples from 11 vegetation types, this study investigated the influence of different types of vegetation restoration on soil quality using an integrated soil quality index (SQI) and a generalized linear model (GLM). Vegetation types had significant effects on soil properties and thus on soil quality. SQI was developed by using TN, TP, TK, AP, and clay content; TN had highest weighting values (0.58), which indicated that it contributed the most to final SQI. The highest and lowest SQI values were observed for primary forest and cropland, respectively. Overall, vegetation restoration (e.g., natural restoration, artificial forests and artificial grassland) improved soil quality significantly. A GLM model explained 73.20% of the total variation in SQI, and vegetation type explained the largest proportion (46.39%) of the variation, which implies that the vegetation restoration practices can greatly enhance the soil quality in karst landscapes of southwest China. The results of this study may be used to improve implication of ecological restoration and management in degraded regions.

Polymeric carbon nitride is a promising candidate for metal-free photocatalysis, but it is hampered by low activity due to poor carrier separation efficiency and lack of active sites. We have constructed a bifunctionally-modified structure, containing cyano groups internally and carboxyl groups on the surface, that was about 205 times more active than unmodified carbon nitride. The internal cyano groups enhanced the photoelectric performance of carbon nitride, while the surface carboxyl groups acted as active sites to promote hydrogen production. It is anticipated that this work will inform the rational design of polymeric carbon nitride and inspire similar attempts to modify polymers.

A high aniline yield was achieved by the combination of near-UV light as the driving force of nitrobenzene reduction and a ZnNb2O6 surface as the product-selective controller. Here, a ZnNb2O6 fibre, having a wide band gap and both acidic and basic sites, was exploited by a novel ion-exchange method to study the effect of the surface acidity and basicity of catalysts on the product selectivity under near-UV light irradiation without the interference of photo-generated carriers. ZnNb2O6 showed the highest aniline yield compared to Nb2O5 and ZnO. The results of experimental and theoretical calculations confirmed that the acidic sites on the surface of ZnNb2O6 promoted the breakage of the N–O bond in the intermediate phenylhydroxylamine while the basic sites were attached to the dissociated hydrogen of isopropyl alcohol, resulting in high aniline selectivity.

Karst landscape, covers more than 10% of the global land surface and plays an important role in supporting ecosystems and human society, may be strongly influenced by climate change. Vegetation available water (VAW) is a key variable impacting the sensitivity of ecosystems to a changing environment. However, VAW in karst region is difficult to determine and remains uncertain. This study improved a dynamic Budyko-type water balance model, by introducing a nonlinear equation linking climate, vegetation and Budyko-type water balance. This model was calibrated using evolutionary algorithm based on monthly runoff. Comparison results in the Pearl, Yangtze and 12 karst catchments in south China, suggested high effectiveness of this improved model in simulating monthly runoff and evapotranspiration. Furthermore, in the 12 karst catchments, the max VAW was negatively correlated to the portion of karst landscape of the catchment (POK, r = −0.63, α = 0.027) and the elasticity of evapotranspiration to precipitation (r = −0.60, α = 0.04). These implied that karst catchments with higher POK had lower VAW, making the ecosystems rely more on precipitation.

Purpose: The dependence of patients with chronic diseases on drugs may affect their health-related quality of life (HRQoL). This study aims to assess the relationship between the direct economic burden caused by out-of-pocket (OOP) payments, drug accessibility, sociodemographic characteristics, and health-related quality of life.Methods: 1,055 patients with chronic diseases from Gansu, Hebei, Sichuan, Zhejiang, and Tianjin were investigated. Data collection included basic conditions and economic and health insurance conditions of patients with chronic diseases. The CLAD and Tobit regression models were used to analyze and compare the health-related quality of life and influencing factors of patients with chronic diseases in five districts. Differentiated analysis was conducted through sub-sample regression to explore the variable health effects of patients with single and multiple diseases.Results: A total of 1,055 patients with chronic diseases participated in the study, 54.4% of whom were women. The overall average utility score was 0.727, of which Sichuan Province was the highest with 0.751. Participants reported the highest proportion of pain/discomfort problems, while patients reported the least problems with self-care. The improvement of drug accessibility and the reduction of the burden of out-of-pocket expenses have significant positive effects on HRQoL. Various sociodemographic factors such as age and gender also have significant impact on HRQoL of patients with chronic diseases. HRQoL of patients with multiple chronic diseases is more affected by various influencing factors than that of patients with single disease.Conclusion: In order to improve the quality of life of patients with chronic diseases, it is of great importance to ensure the accessibility of drugs and reduce patients' medication burden. Future focus should shift from preventing and controlling chronic diseases as individual diseases to meeting the comprehensive health needs of people suffering from multiple diseases.

Summary The controlled generation of reactive oxygen species (ROS) to selectively epoxidize styrene is a grand challenge. Herein, cyano-group-modified carbon nitrides (CNCYx and CN-Ty) are prepared, and the catalysts show better performance in regulating ROS and producing styrene oxide than the cyano-free sample. The in situ diffuse reflectance infrared and density functional theory calculation results reveal that the cyano group acts as the adsorption and activation site of oxygen. X-ray photoelectron spectroscopy and NMR spectrum results confirm that the cyano group bonds with the intact heptazine ring. This unique structure could inhibit H2O2 and ⋅OH formation, resulting in high selectivity of styrene oxide. Furthermore, high catalytic activity is still achieved when the system scales up to 2.7 L with 100 g styrene under solar light irradiation. The strategy of cyano group modification gives a new insight into regulating spatial configuration for tuning the utilization of oxygen-active species and shows potential applications in industry., Graphical Abstract, Public summary • Surface group modification is a significant strategy to improve catalyst activity • Cyano groups are incorporated on the surface of carbon nitride via copolymerization • Cyano group reactive sites allow high selectivity of styrene oxide for aerobic oxidation • The system can be scaled up under solar light irradiation

To prevent soil erosion and improve ecological environment over the Loess Plateau, the Chinese Government implemented a large scale ecological restoration (ER) in the past decades. ER activities have successfully reduced soil erosion and expanded vegetation, and also changed the water-energy balance, which would alter the hydrological dryness conditions. Knowledge of the impacts of land surface changes on hydrological dryness is essential for ER-related policy making and management. However, so far few studies have addressed this important issue. Thus, this study aimed to evaluate the effects of land surface changes on hydrological dryness in 13 main catchments in the Loess Plateau during 1961–2009, based on the standardized wetness index ( SWI ), which can be used to measure the hydrological dryness resulting from climate change solely (denoted as SWI c ) and from the joint effects of climate and land surface changes (denoted as SWI cl ). Statistical analysis (correlation r > 0.80 ) demonstrated that the land surface changes, being represented by the LIM (total affecting area of terrace and check-dams), RM (total affecting area of replanted trees and pastures), LAI (leaf area index), and VC (vegetation coverage), dominated the behaviors of n (a parameter of the Budyko-type formulae). The overall increasing n indicated that more and more water from precipitation becomes evapotranspiration in the past decades. Furthermore, both the SWI c and SWI cl decreased; however, the trend in SWI cl was (−2.7 ± 0.76) × 10−3 month−1, being visibly larger than that of SWI c ((−1.3 ± 0.65) × 10−3 month−1). These suggested that the Loess Plateau was becoming drier, while the land surface changes might have enhanced the drying tendencies.

Southwest China, as one of the largest continuous karst areas in the world, is a severely eroded region due to its special geological condition. Thus, soil and water conservation measures such as dam construction have been extensively implemented in this region to control sediment delivery. However, it remains unclear how dam construction affects multiscale variability of sediment discharge (SD) and its potentially influential factors in southwest China. To assess this, annual SD, water discharge (WD), precipitation (PT), potential evapotranspiration (PET), and normalized differential vegetation index (NDVI) data from 1955 to 2015 were obtained from two karst watersheds of Liujiang (no large dams) and Hongshui (dam-controlled). These sites shared the similar climatic conditions. The Mann-Kendal test, Wilcoxon rank-sum test, and continuous wavelet transform analysis was used to detect the trends and periodicity in SD, and wavelet coherence analysis were employed to detect the temporal covariance between SD and WD, PT, PET, and NDVI. Results indicated that the multiscale variability of SD was strongly influenced by dam construction. The annual SD showed significant 4-year periodic oscillation in the Liujiang watershed, while no significant cycles were found in the Hongshui watershed. Dam construction exerted substantial influence on the multiscale correlations between SD and its associated factors. The time scales that the NDVI resonated with SD were concentrated on the periodicity of 2- and 3-year in the Liujiang watershed. In contrast, no significant periodicities were observed in the Hongshu watershed. This study yields a greater understanding of SD dynamics, and is helpful for better watershed management in karst areas of southwest China.

Polyunsaturated fatty acids (PUFAs) play a pivotal role in the biological effects, and are the potential biomarkers for some diseases. However, the structural diversity and similarity, the low concentration, and the interference of high abundant endogenous components challenge the PUFAs profiling. Herein, a novel analytical approach, off-line and on-line solid phase extraction-nano-liquid chromatography-quadrupole-time-of-flight mass spectrometry (off-line and on-line SPE-nano-LC-Q-TOF-MS), was established to monitor the PUFAs. The combination of off-line and on-line SPE removed most of impurities, and the recoveries ranged from 80.1% to 93.0% and the matrix effects were from 85.1% to 92.8%. Using this method, 51 PUFAs could be separated well and quantified with the limits of quantification between 0.006 and 2.2 pg. Finally, this developed method was applied successfully to simultaneously qualify and quantify the potential biomarkers in the allergic patients. 21 PUFAs including LTB4, 5S-, 11S-, 15S-HETE and 15S-HEPE showed significant differences. Our study indicated that the established method has the potential to sensitively and accurately determine the PUFAs in biological samples.

Indicating soil quality usually requires many soil properties of which the measurements are time consuming. Therefore, it is desirable to developing simple and effective indices for reflecting soil quality based on soil properties that can be readily obtained. The soil physical quality index, S-index, derived from the slope at the inflection point of the water retention curve (particularly the Van-Genuchten equation), is a comprehensive index for indicating soil properties. By comparing the S-index with a widely used soil quality index (SQI), this study used 298 samples to determine soil chemical and physical properties for calculating SQI, and found that the correlation coefficient between the S-index and SQI was 0.88, indicating that the S-index can represent soil quality well. An artificial neural network (ANN) model and a linear regression (LR) model were proposed for estimating S-index. Results showed that the ANN model was better than LR model in estimating S-index. Particularly, the ANN model with the soil bulk density and soil organic carbon (scenario A1) as inputs, had the highest R2 of 0.807, while the LR model get the highest R2 (predicted v.s. observed) of 0.75 with the combination of soil organic carbon, soil bulk density, total nitrogen and available nitrogen. This study is helpful for extending the applications of S-index.

As one of the largest karst regions in the world, southwest China is experiencing severe soil erosion due to its special geological conditions, inappropriate land use, and lower soil loss tolerance. Knowledge and accurate estimations of changes in sediment discharge rates is important for finding potential measures to effectively control sediment delivery. This study investigated temporal variation in monthly sediment discharge ( SD ), and developed sediment rating curves and state-space model to estimate SD . Monthly water discharge, SD , precipitation, potential evapotranspiration, and normalized differential vegetation index during 2003–2015 collected from a typical karst catchment of Yujiang River were analyzed in present study. A Mann-Kendal test and Morlet wavelet analysis were employed to detect the changes in SD . Results indicated that a decreasing trend was observed in sediment discharge at monthly and annual scale. The water and sediment discharge both had a significant 1-year period, implying that water discharge has substantial influence on SD . The best state-space model using water discharge was a simple but effective model, accounting for 99% of the variation in SD . The sediment rating curves, however, represented only 78% of the variation in SD . This study provides an insight into the possibility of accurate estimation of SD only using water discharge with state-space model approach. State-space model is recommended as an effective approach for quantifying the temporal relationships between SD and its driving factors in karst regions of southwest China.

Soil pedotransfer functions (PTFs) are alternatives to expensive field and laboratory methods for acquiring soil hydraulic properties. Traditional PTFs generally require soil physiochemical properties (such as particle size distribution, bulk density, soil organic matter, etc.) as inputs. Soil spectral information is, more recently, being considered as an additional input property for improving the performance of PTFs. To date, however, there are only a few studies focused on this issue. Using 171 in-situ saturated soil hydraulic conductivity (Ks) observations in southwestern China and an Artificial Neural Network model (ANN), we developed three different PTFs, with different inputs, to estimate the saturated hydraulic conductivity. The inputs include the basic soil properties (denoted as BSP, bulk density, % clay, % silt and % sand) and soil spectral data (SPRD, dimension reduced by using the principal component analysis (PCA) method). We evaluated the performance of the new PTFs using the determination coefficient (R 2 ), root mean square error (RMSE) and Akaike's information criterion (AIC). The results showed that including the SPRD as an additional input improved the performance of the PTF for estimating Ks. Compared to the PTF that solely used BSP as inputs, the R 2 of the PTF, which used both the BSP and SPRD as inputs, increased by 0.33 (from 0.09 to 0.42) and the RMSE and AIC decreased by 0.26 (from 1.38 to 1.12) and 18.16 (from 273.96 to 255.8), respectively. These results indicate the potential of SPRD to improve the performance of PTF in estimating hydraulic conductivity.

The electronic and interfacial properties of catalysts play vital roles in tailoring catalytic performance. Here, we report that the modification of polymeric carbon nitride (PCN) with cyano group ( CN) can achieve excellent catalytic performance in mineralization of phenol. The CN site not only enhances the adsorption and activation of molecular O2 for efficient H2O2 production, but also improves the absorption capability of PCN for phenol in aqueous solution by tuning surface charge states. Subsequently, the surficial adsorbed phenol acts as holes scavenger which promotes the separation efficiency of photogenerated carriers in PCN and in turn facilitates the in-situ decomposition of H2O2 to OH. This reduces the uncontrollable decomposition of H2O2 to OH and inhibits the polymerization of phenolic compounds. The active sites of catalyst, O2 transformation state and pathway on the catalyst surface as well as the firstly attacked sites of phenol are confirmed respectively by in-situ DRIFT spectra, scavengers and Bader charge analysis.