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Traditional dental implant navigation systems (DINS) based on binocular stereo vision (BSV) have limitations, for example, weak anti-occlusion abilities, as well as problems with feature point mismatching. These shortcomings limit the operators' operation scope, and the instruments may even cause damage to the adjacent important blood vessels, nerves, and other anatomical structures. Trinocular stereo vision (TSV) is introduced to DINS to improve the accuracy and safety of dental implants in this study. High positioning accuracy is provided by adding cameras. When one of the cameras is blocked, spatial positioning can still be achieved, and doctors can adjust to system tips; thus, the continuity and safety of the surgery is significantly improved. Some key technologies of DINS have also been updated. A bipolar line constraint algorithm based on TSV is proposed to eliminate the feature point mismatching problem. A reference template with active optical markers attached to the jaw measures head movement. A T-type template with active optical markers is used to obtain the position and direction of surgery instruments. The calibration algorithms of endpoint, axis, and drill are proposed for 3D display of the surgical instrument in real time. With the preoperative path planning of implant navigation software, implant surgery can be carried out. Phantom experiments are carried out based on the system to assess the feasibility and accuracy. The results show that the mean entry deviation, exit deviation, and angle deviation are 0.55 mm, 0.88 mm, and 2.23 degrees, respectively. [ABSTRACT FROM AUTHOR]

To further improve the emission reduction effect on asphalt smoke and mitigate environmental pollution, a novel emission reduction agent (TBD) combined with physical adsorption and chemical degradation was synthesized with tourmaline, biochar, and diatomite. The testing and evaluation method for the emission reduction efficacy of TBD has been established. The optimal preparation method and parameter of TBD were selected based on macroscopic performance and microscopic analysis. The results indicated that TBD had the highest emission reduction rate and most stable storage under the ball milling process. According to XRD, FTIR, SEM, and BET, TBD with the multistage porous structure and spontaneous polarization effect was synthesized by the ball milling parameter of 200r-2 h. The emission reduction efficiency of TBD on the asphalt smoke effect was enhanced by a synergistic interaction of the physical adsorption and chemical degradation. The emission reduction rate was up to 65.84% for 3 h. This laid the foundation for the development and promotion of low-pollution asphalt. [ABSTRACT FROM AUTHOR]

To further improve the emission reduction efficiency and enhance the road performance of emission reduction modified asphalt. A low-pollution asphalt (TBD-A) was prepared with tourmaline, biochar, and diatomite (TBD). A testing and evaluation method for the emission reduction efficacy of TBD-A has been proposed. The road performance of TBD-A was evaluated based on DSR, MSCR, BBR, and LAS. The evolution law of the emission reduction effect of TBD-A was clarified. Based on DSC, FTIR, and TG, the improvement mechanism of the road performance and emission reduction mechanism of TBD-A were revealed. The results show that the high-temperature performance, creep recovery ability, and fatigue life of TBD-A increase with TBD content rising. The low-temperature performance of TBD-A is superior to that of asphalt slurry. Controlling the TBD content and temperature can ensure the excellent low-temperature performance of TBD-A. The emission reduction efficacy of TBD-A increases as temperature and adsorption time rise. The comprehensive emission reduction rate of TBD-rubber-powder asphalt is the highest, reaching 64% at 190 °C. TBD and asphalt are physically blended. TBD increases asphalt's glass transition temperature while decreasing the thermal decomposition rate. The temperature stability and sensitivity of asphalt have been improved. Asphalt harmful substances are adsorbed by the multi-level pore structure of TBD, as well as are reduced and degraded by the spontaneous polarization effect. • The road performance of low-pollution asphalt was evaluated. • The emission reduction efficacy of low-pollution asphalt was clarified. • The modification mechanism of low-pollution asphalt was revealed. [ABSTRACT FROM AUTHOR]

[Display omitted] • 40Ar-39Ar dating results show Nanxiong basalts were erupted during 76.2–69.9 Ma. • Nanxiong basalts are alkaline to calc-alkaline basalts with OIB-like features. • Nanxiong basalts were derived from metasomatized asthenospheric mantle. • Formations of Nanxiong basalts indicate the rollback of subducted Paleo-Pacific Plate. The Cretaceous arc-related and intraplate mafic rocks are widely distributed across Southeast (SE) China, and provide important information for investigating the Cretaceous dynamical processes of the Paleo-Pacific Plate. This study presents new petrological, geochronological, and geochemical analyses for the Late Cretaceous basalts from the Nanxiong Basin in SE China. The Nanxiong basalts yield the 40Ar/39Ar plateaus ages of 76.2–69.9 Ma, they belong to alkaline-calc-alkaline basalts and have OIB-like geochemical patterns with enrichment on LILEs and LREEs. These basalts have initial 87Sr/86Sr ratios of 0.7055–0.7062 and ε Nd (t) values of + 2.5-+3.4. Such signatures suggest that the Nanxiong basalts were the products of partial melting of asthenospheric mantle, which might be metasomatized by slab-derived melts with a proportion of sediments. Our new results, along with the regional reported ages and geological observations, suggest that the Nanxiong OIB-like basalts were formed in an intraplate extensional setting, in response to the rollback of the subducted Paleo-Pacific slab during the Late Cretaceous. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the protective effect and the mechanism of tauroursodeoxycholic acid (TUDCA) against hepatic ischemia reperfusion (IR) injury. Male Balb/c mice were intraperitoneally injected with tauroursodeoxycholic acid (400 mg/kg) or saline solution, once per day for 3 days before surgery, and then the model of hepatic I/R injury was established. Blood and liver samples were collected from each group at 3, 6, and 24 h after surgery. Liver pathological changes, liver function, hepatocyte apoptosis and proinflammatory factors were detected. KCs were extracted, cultured and treated with TUDCA or phosphate-buffered saline (PBS) for 24 h, and then viability and phagocytosis were examined. Additionally, IRE1α/TRAF2/NF-κB pathway activity and AML cell apoptosis were detected. The results showed that TUDCA alleviated hepatic I/R injury, the level of liver function markers, and hepatocyte apoptosis in vivo. Furthermore, the proinflammatory effects of KCs were suppressed by down-regulating IRE1α/TRAF2/NF-κB pathway activity in vivo. TUDCA dose-dependently suppressed the expression of inflammatory factors and IRE1α/TRAF2/NF-κB pathway activity in vitro, consistent with the in vivo results. Therefore, TUDCA can effectively alleviate hepatic IR injury by down-regulating the activity of the IRE1α/TRAF2/NF-κB pathway to suppress the function of KCs. [ABSTRACT FROM AUTHOR]

Liver ischemia–reperfusion injury (IRI) is a major complication in the perioperative period and often leads to liver failure and even systemic inflammation. Previous studies have suggested that the inflammatory response participated in the liver damage during liver IRI. Nicotinamide phosphoribosyl transferase (NAMPT) is required for the maintenance of cellular nicotinamide adenine dinucleotide (NAD+) levels, catalyzing the rate-limiting step in the NAD + salvage pathway. NAMPT is strongly upregulated during inflammation and constitutes an important mechanistic link between inflammatory, metabolic, and transcriptional pathways. The aim of our study was to investigate the role of NAMPT in liver IRI. We investigated the effect of pharmacological inhibition of NAMPT with FK866 in models of liver IRI. Liver damage was assessed by HE staining, serum ALT/AST, and TUNEL staining. To examine the mechanism, primary hepatocytes, liver macrophages and RAW264.7 cells were treated with or without NAMPT inhibitors before hypoxia-reoxygenation. Liver macrophages and RAW 264.7 cells activation in vitro was evaluated by western blotting, flow cytometry, and ELISA. We found that NAMPT was upregulated in liver IRI. Treatment with the NAMPT inhibitor FK866 ameliorated liver IRI and suppressed inflammation in mice. Although NAMPT plays an important role both in hepatocytes and liver macrophages, we focused on the impact of NAMPT on liver macrophages. The mechanism revealed that FK866 potently inhibited NAMPT activity, as demonstrated by reduced liver NAD+ and intracellular NAD+, resulting in reduced abundance and activity of NAD + -dependent enzymes, including poly (ADP-ribose) polymerase 1 (PARP1), thus inhibiting macrophage M1 polarization by reducing CD86, iNOS, TNF-α, and interleukin (IL)-1β. Taken together, our data suggested that NAMPT can regulate macrophage polarization through NAD+/PARP1 to ameliorate liver injury, and that FK866-mediated NAMPT blockade may be a therapeutic approach in liver IRI. • NAMPT inhibition can attenuate liver ischemia–reperfusion injury. • NAMPT inhibition reduces the apoptosis both in hepatocyte and liver macrophages. • FK866 reduces the pro-inflammatory response and decreases M1 macrophage polarization. • FK866 reduces inflammation in macrophages through NAD + -PARP1 pathway. [ABSTRACT FROM AUTHOR]

Protein adsorption plays a key role in determining the biological properties of calcium phosphate biomaterials. Calcium (Ca) and phosphate (P) ions are involved in the protein adsorption process and influence the protein adsorption behaviors. In this study, the proteins adsorption on hydroxyapatite (HA) (001), (100), (110), (010) surfaces with Ca, P ions in solution were investigated by Molecular Dynamics (MD) simulation. The results reveal that basic proteins were more favorable to adsorb on HA surface than acidic proteins. HA (110) surface absorbed more acidic proteins than HA (001) and (100). HA (010) surface adsorbed more basic protein. Basic residues play a more important role than acidic residues in the adsorption process, as the basic residues have shown higher absorption energy than acidic residues, and they were more likely to adsorb on HA surfaces than to bind P ions in solution. Most of the active sites of protein, especially for acidic residues, are prefer to interact with HA surface through water molecules. Basic residues are more likely to adsorb onto HA surfaces directly. The presence of Ca, P ions in solution can influence the adsorption behaviors of protein. The formation of Ca, P ion cluster may lead to desorption of proteins. And they can compete with water molecules to bond to HA surfaces, acting as a bridge of protein interacting with HA surfaces instead of water-bridge. This Ca, P ions bridge connection make the adsorption energy of protein weakened. The results of this study provided new information at atomic/molecular level to further interpret the mechanism of protein adsorption on calcium phosphate surfaces with Ca, P ions. It is also helpful for designing new calcium phosphate biomaterials with specific surface properties to adsorb target protein for biomedical applications. [ABSTRACT FROM AUTHOR]

• The most suitable ecological streamflow was calculated via kernel density estimation method. • Ecological drought was identified using the variable threshold method based on ecological streamflow. • Impacts of climate variability and human activities on ecological drought were quantified. • Human activities are the dominant factor aggravating the ecological drought in the Weihe River Basin. Although various studies have investigated the impacts of climate variability and human activities on drought, researches specifically analysing the impact on ecological drought are still limited. A deep understanding of the climatic and anthropogenic effects on ecological drought processes is crucial for ecological regulation and management in the changing environments. In the present study, an integrated approach for comprehensive understanding and quantification of ecological drought in rivers was proposed which first applied the nonparametric kernel density estimation (KDE) method to calculate the most suitable ecological streamflow (MSES) for a river ecosystem. Then, the variable threshold level method based on the MSES for each month and the run theory method were applied to identify the ecological drought duration and deficit volumes. Finally, a quantification approach based on hydrological model simulation was proposed to attribute the impacts of climate variability and human activities on ecological drought. The proposed approach was applied on two catchments, Xianyang (XY) and Huaxian (HX) within the Weihe River Basin (WRB) in northern China. Comparison results obtained using the two empirical methods revealed that the MSES calculated using the KDE method was reasonable and can be used for ecological drought identification. The identification results showed that both the median and upper quartile values of the drought duration and deficit volumes during the disturbed period (1991–2017) were greater than those during the undisturbed period (1961–1990). Quantification results showed that human activities were the dominant factor aggravating ecological drought in the WRB after 1990. The contribution rates of climate variability and human activities toward ecological drought variations were 25.6% and 74.4%, respectively, for the XY station and 42.7% and 57.3%, respectively, for the HX station. Although the WRB was selected as a case study, the proposed approach can also be applied to other regions to provide scientific guidance for regional ecological management. [ABSTRACT FROM AUTHOR]

• Nonstationary models that incorporate climatic variables and reservoir index are constructed. • The nonstationary models provide a better fitting of nonstationary flood and low flow series. • Nonstationary frequency analysis of flood and low flow in upper of Huaihe River Basin are conducted. • Climatic and reservoir impacts are related to nonstationarity of flood and low flow respectively. Conventional water infrastructure designs for flood and low flows are usually based on the assumption of stationarity of extreme events. However, recent evidence suggests that the influences of climate variability and human activities have made the hypothesis of stationarity questionable. In this study, we used the generalized additive models for location, scale, and shape (GAMLSS) to construct a nonstationary model in which the parameters of the selected distributions were modelled as a function of climatic variables (i.e., climate indices and precipitation) and/or the reservoir index (RI). The nonstationary models were then used to analyse annual flood and low flow frequency at four hydrological stations in the upper reaches of the Huaihe River Basin, including Dapoling (DPL), Changtaiguan (CTG), Zhuganpu (ZGP), and Xixian (XX) stations. Annual floods were represented by the maximum daily streamflow in each year, and low flows were represented by the 95th quantile of the daily streamflow (Q 95) in each year. The change point and trend analysis revealed that the flood series of the ZGP station and the low flow series of the DPL and XX stations exhibited significant downward and upward trends (p < 0.1)), respectively. The low flow series of the ZGP station showed a significant change point in 1980 (p < 0.1). GAMLSS modelling results showed that, in comparison with stationary models, nonstationary models that included precipitation and the Arctic Oscillation climate index as covariates for the gamma distribution location parameter provided a superior description of the flood series at the four stations. Nonstationary models that incorporated precipitation and/or RI as covariates for the Weibull distribution parameters fit the low flow series better than stationary models at all stations. Furthermore, we found that nonstationary models outperformed stationary models in terms of flood frequency analysis, covering all flood observation points and capturing the generally decreasing trend in flood series, as well as a decrease in the scatter of estimated flood value magnitudes. For the low flow frequency analysis, the comparison results showed that the nonstationary and stationary models performed identically for the DPL, CTG, and XX stations, where no significant change point was detected. However, for the ZGP station, where a significant change point was detected, the nonstationary models performed better than the stationary models and could accurately capture the changes in the magnitude of the estimated low flow values before and after the change point. Overall, the proposed nonstationary model can serve as a tool for nonstationary frequency analysis of flood and low flow series under the influence of climate variability and reservoir regulations, thus providing a reference for regional water infrastructure design. [ABSTRACT FROM AUTHOR]

• Nonstationary models that incorporate climatic variables and reservoir index are constructed. • The nonstationary models provide a better fitting of nonstationary flood and low flow series. • Nonstationary frequency analysis of flood and low flow in upper of Huaihe River Basin are conducted. • Climatic and reservoir impacts are related to nonstationarity of flood and low flow respectively. Conventional water infrastructure designs for flood and low flows are usually based on the assumption of stationarity of extreme events. However, recent evidence suggests that the influences of climate variability and human activities have made the hypothesis of stationarity questionable. In this study, we used the generalized additive models for location, scale, and shape (GAMLSS) to construct a nonstationary model in which the parameters of the selected distributions were modelled as a function of climatic variables (i.e., climate indices and precipitation) and/or the reservoir index (RI). The nonstationary models were then used to analyse annual flood and low flow frequency at four hydrological stations in the upper reaches of the Huaihe River Basin, including Dapoling (DPL), Changtaiguan (CTG), Zhuganpu (ZGP), and Xixian (XX) stations. Annual floods were represented by the maximum daily streamflow in each year, and low flows were represented by the 95th quantile of the daily streamflow (Q 95) in each year. The change point and trend analysis revealed that the flood series of the ZGP station and the low flow series of the DPL and XX stations exhibited significant downward and upward trends (p < 0.1)), respectively. The low flow series of the ZGP station showed a significant change point in 1980 (p < 0.1). GAMLSS modelling results showed that, in comparison with stationary models, nonstationary models that included precipitation and the Arctic Oscillation climate index as covariates for the gamma distribution location parameter provided a superior description of the flood series at the four stations. Nonstationary models that incorporated precipitation and/or RI as covariates for the Weibull distribution parameters fit the low flow series better than stationary models at all stations. Furthermore, we found that nonstationary models outperformed stationary models in terms of flood frequency analysis, covering all flood observation points and capturing the generally decreasing trend in flood series, as well as a decrease in the scatter of estimated flood value magnitudes. For the low flow frequency analysis, the comparison results showed that the nonstationary and stationary models performed identically for the DPL, CTG, and XX stations, where no significant change point was detected. However, for the ZGP station, where a significant change point was detected, the nonstationary models performed better than the stationary models and could accurately capture the changes in the magnitude of the estimated low flow values before and after the change point. Overall, the proposed nonstationary model can serve as a tool for nonstationary frequency analysis of flood and low flow series under the influence of climate variability and reservoir regulations, thus providing a reference for regional water infrastructure design. [ABSTRACT FROM AUTHOR]

During the high-temperature construction of hot mix asphalt mixture, a large number of harmful emissions such as asphalt smoke are produced, which seriously endangers the workers' health and pollutes the surrounding environment. The object of this study is to reduce the emission of asphalt smoke and improve the construction environment. Tourmaline (T), graphene oxide (GO), KH 550 silane coupling agent (K) were used to prepare GO/KT-modified asphalt and the influence of modifier content on the asphalt basic performance was studied. The micromorphology and chemical constituents of the modified asphalt were analyzed, and the asphalt smoke adsorption effect of the modified asphalt was evaluated. It provides a useful reference for the green and sustainable development of road infrastructure. The results show that GO/KT composite powder can improve the asphalt basic performance. GO/KT has an excellent adsorption effect on asphalt smoke, and the emission reduction rate of GO/KT-modified asphalt can reach 41.11%. Considering the asphalt basic performance, asphalt smoke adsorption performance, and economic benefits, the recommended GO/KT and GO appropriate contents are 20 wt% and 1.0 wt%, respectively. [ABSTRACT FROM AUTHOR]

• An observation-based natural and human-impacted catchment comparison method is proposed. • Human influence are quantified based on gridded socio-economic and land use data. • Climatic and anthropogenic influences on drought propagation are investigated. • Climate change accelerates the response of hydrological drought to meteorological drought. • Human activities delay the propagation from meteorological to hydrological drought. It is crucial to investigate how a precipitation deficit is transformed into hydrological drought and how climate change and human activities affect this transformation process, which is helpful to gain a deep understanding of drought propagation process in this changing environment. This study proposed an observation-based natural and human-impacted catchment comparison method to assess the impacts of climate change and human activities on propagation from meteorological drought to hydrological drought. The method mainly consists of the following three steps: (1) selection of natural catchments through analysis of trends and change points of hydro-meteorological data, as well as statistics analysis of human influence based on land use and socio-economic indicators data sets; (2) calculation of drought propagation characteristics (e.g., drought severity, duration, and propagation time) based on run theory and the Pearson correlation coefficient; and (3) comparison of drought propagation characteristics of natural catchments between undisturbed and disturbed periods to identify the impacts of climate change on drought propagation, and comparison of the propagation characteristics between natural and human-impacted catchments during the disturbed period to investigate human influence on drought propagation. The Laohahe basin (with eleven sub-catchments), located in northern China, was evaluated via the proposed procedure, and standardized precipitation index (SPI) and standardized runoff index (SRI) were used to characterize meteorological and hydrological droughts, respectively. The results demonstrate that the proposed method is suitable tool for distinguishing natural and human-impacted catchments, and separating the impacts of climate change and human activities on drought propagation. Furthermore, the comparison results of different schemes show that climate change accelerates the propagation from meteorological drought to hydrological drought in the Laohahe basin, shortening it by approximately 3 months. Human activities, however, disturb and then delay the natural propagation from meteorological drought to hydrological drought, retarding it by 11–12 months. Although the Laohahe basin was selected as a case study in this paper, the proposed method can be applied in other regions as well to improve drought prediction and water resources management. [ABSTRACT FROM AUTHOR]

A large number of harmful components are produced during asphalt pavement construction under high-temperature conditions, causing heavy environmental pollution. Adding emission reduction agents to asphalt as an effective emission reduction technology has been widely used in different nations. However, few studies have attempted to compare the used emission reduction agents and their performances, resulting in the difficulty of the selection of emission reduction agents to reduce volatile organic compounds effectively and purposely. The objective of this review paper is to systematically summarize and analyze the state-of-the-art studies on asphalt volatile organic compounds emission reduction. In this study, the components in asphalt volatile organic compounds were summarized and the restrictions on asphalt volatile organic compounds emission in different nations are reviewed and summarized firstly. Then, the commonly used emission reduction agents of asphalt volatile organic compounds were completely investigated and sorted. Afterward, the emission reduction effect and engineering performance were compared in detail. Finally, the emission reduction mechanisms of different emission reduction agents were illustrated. The main findings show that the asphalt volatile organic compounds contain nearly ten categories of main components. The emission reduction effect of inorganic porous materials is superior to others. The organic polymer materials and the appropriate amount of inorganic materials can improve asphalt's engineering performance. The emission reduction mechanisms of emission reduction agents were divided into crosslinking reaction, adsorption, and piezoelectric/thermoelectric effect according to the interaction between asphalt volatile organic compounds and emission reduction agents. [ABSTRACT FROM AUTHOR]

• A blast furnace slag-based mortar grouting material (BFSBM) was developed from industrial by-product. • The optimum mix ratio of grouting material was determined based on its rheological properties and mechanical strengths. • A new self-developed experimental device was designed for the grouting simulation to study the grouting effects. Introducing the blast furnace slag (BFS) into grouting materials not only can improve its performances significantly but also can recycle the industrial by-product economically. The current researches related to BFS mainly focus on the preparation and evaluation of BFS-based paste (BFSBP). However, the grouting effects of hardened grout stone body with BFS-based mortar (BFSBM) are investigated rarely. In this study, a BFSBM material was developed based on BFS and its optimum mix ratio was determined. A new self-developed grouting simulation device was designed to study the grouting effects of hardened grout stone body based on different road grades and grouting diffusion radii. The results show that the optimum mix ratio of BFSBM determined as m SS / m BFS , m SH / m BFS , m W / m BFS, and m S / m BFS are 0.11, 0.09, 0.42 and 0.4, respectively (SS, SH, W, and S represent sodium silicate, solid sodium hydroxide, purified water, and sand, respectively). BFSBM has a good grouting effect on void road bases and the highest 7d compressive strength of the core sample taken from the expressway highway void base reaches 13.2 MPa. The 7d compressive strength of the core sample 60 cm away from the grouting hole is 63.2% higher than the compressive strength in the requirements. [ABSTRACT FROM AUTHOR]

A sensitive and biocompatible N-rich probe for rapid visual uranium detection was constructed by grafting two trianiline groups to 2,6-bis(aminomethyl)pyridine. Possessing excellent aggregation-induced emission (AIE) property and the advantages to form multidentate chelate with U selectively, the probe has been applied successfully to visualize uranium in complex environmental water samples and living cells, demonstrating outstanding anti-interference ability against large equivalent of different ions over a wide effective pH range. A large linear range (1.0 × 10−7–9.0 × 10−7 mol/L) and low detection limit (72.6 nmol/L, 17.28 ppb) were achieved for the visual determination of uranium. The recognition mechanism, photophysical properties, analytical performance and cytotoxicity were systematically investigated, demonstrating high potential for fast risk assessment of uranium pollution in field and in vivo. [ABSTRACT FROM AUTHOR]

• A comprehensive approach for identifying drought termination characteristics is proposed. • Natural and human-influenced hydrological drought termination characteristics are identified. • Human activities significantly aggravate the drought termination duration, deficit and rate. • Human activities lead to shifts in drought termination seasonality. Although many previous studies have analysed the impacts of human activities on hydrological drought, studies that analysed these impacts from the perspective of drought termination, a critical re-wetting phase of hydrological drought, are limited. A deeper understanding on how human alter hydrological drought termination phase is essential for improving drought recovery prediction and performance of the drought early warning system. In this study, a comprehensive approach for identifying hydrological drought termination characteristics and quantifying the impact of human activities on drought termination was proposed. This approach, which combines the concept of drought termination (DT), an 'observed–simulated' comparison approach, and the variable threshold level method (TLM v), consists of the following steps: (1) reconstruction of natural streamflow using a hydrological model, (2) identification of hydrological drought termination characteristics using TLM v method and the concept of drought termination, and (3) quantification of human influence by comparison of the hydrological drought termination characteristics of human-influenced (observed) series and those of natural (simulated) series. The Laohahe basin, consists of four catchments (Xiquan, Xiaochengzi, Dianzi, and Taipingzhuang) in northern China, was evaluated using the proposed procedure. The study demonstrated that the proposed approach is efficient in quantifying human influence on hydrological drought termination phase. The results revealed that human activities have significant impacts on the hydrological drought termination phase in the Xiaochengzi, Dianzi, and Taipingzhuang catchments. All the average drought termination duration (DT dur), deficit (DT def), and rate (DT rate) in the human-influenced series of the three catchments (Xiaochengzi, Dianzi, and Taipingzhuang) increased in comparison to those in the natural series, with maximum increases of 230%, 865%, and 35%, respectively. The seasonality of the drought termination phase starts (DT start) and ends (DT end) for the three catchments exhibited obvious shifts due to human influence. The preferred seasons for DT start and DT end were shifted to summer and autumn, respectively. The proposed approach and findings of this study may help to gain a deeper understanding of how human activities alter hydrological drought termination severity (drought termination duration, deficit, and rate) and time (drought termination starts or ends). [ABSTRACT FROM AUTHOR]

• Interactions between BMP-2 and graphene variants studied by molecular dynamics. • Surface modification with O or N enhances interactions due to surface polarity. • Graphene oxide interacts with 2 epitopes of BMP-2, with highest adsorption energy. Graphene and functionalized graphene are intensively studied as biomaterials for bone repair and regeneration. The interactions between graphene/functionalized graphene and key proteins implicated in bone repair are a key event for these applications, but the underlying mechanisms are insufficiently understood. Therefore, we performed molecular dynamics method to study the interactions between bone morphogenetic protein-2 (BMP-2) and perfect graphene, reduced graphene oxide, graphene oxide, and nitrogen functionalized graphene. Results indicated that, the surface modification with oxygen or nitrogen atoms can enhance the interactions between BMP-2 and those surfaces, as a result of the modified surface polarity. Of the four materials studied, graphene oxide was calculated to have the highest adsorption energy for BMP-2, as both the wrist and knuckle epitopes of this protein can interact with the graphene oxide due to its undulated surface morphology at molecular scales. [ABSTRACT FROM AUTHOR]

Adhesive hydrogels are widely applied for biological and medical purposes; however, they are generally unable to adhere to tissues under wet/underwater conditions. Herein, described is a class of novel dynamic hydrogels that shows repeatable and long‐term stable underwater adhesion to various substrates including wet biological tissues. The hydrogels have Fe3+‐induced hydrophobic surfaces, which are dynamic and can undergo a self‐hydrophobization process to achieve strong underwater adhesion to a diverse range of dried/wet substrates without the need for additional processes or reagents. It is also demonstrated that the hydrogels can directly adhere to biological tissues in the presence of under sweat, blood, or body fluid exposure, and that the adhesion is compatible with in vivo dynamic movements. This study provides a novel strategy for fabricating underwater adhesive hydrogels for many applications, such as soft robots, wearable devices, tissue adhesives, and wound dressings. [ABSTRACT FROM AUTHOR]

An Extended Triple Collocation for maximized Correlation (ETCC) method was proposed with a unique correlation function, the purpose of which is to maximize the correlation between the merged product and unknown truth. The method was tested over quasi‐global land by combining three independent precipitation products. The performance of the ETCC‐merged product was then evaluated against three reference data sets and compared with the existing Triple Collocation (TC) merging. The merged product was found to be generally superior to each contributor. Moreover, the ETCC method is better able to improve the correlation of merged product compared with the TC approach. Other improvements are also shown in the absolute difference of the ETCC‐merged product, such as regional validation for central North America and mainland China. These demonstrate the effectiveness of the ETCC method, and accordingly, it can provide a promising solution for maximizing the correlation of merged product without the truth. Plain Language Summary: Precipitation plays a significant role in global atmospheric and hydrological modeling systems. Owing to uncertainties in precipitation estimates from a single satellite or reanalysis product, it is necessary and challenging to blend multi‐source precipitation information to improve the quality of precipitation estimates. The present study proposed a new merging method, called Extended Triple Collocation for maximized Correlation (ETCC), which aims at maximizing the correlation of the merged product against unknown truth. The ETCC‐merged product combined three independent precipitation information derived from the satellite and reanalysis products, and then, was evaluated using three reference data sets. Meanwhile, we compared ETCC's performance with that of the original Triple Collocation (TC) merging. Results show that ETCC method not only performs better than each contributor, but also is more effective in improving precipitation accuracy relative to the TC approach especially in central North America and mainland China. Key Points: A new method is proposed for maximizing the correlation between the merged product and unknown truthThe merged product is more accurate than each contributorThe new method performs better than the original triple collocation [ABSTRACT FROM AUTHOR]

Alkali-activated Materials (AAM) has been applied in road engineering as an environmentally friendly material in recent years. This study prepared road alkali-activated blast furnace slag (AABFS) paste in different mixture ratios based on an orthogonal test scheme. The fluidity, setting time, mechanical strengths, and other properties were systematically evaluated to determine the optimum mixture ratio of paste. Finally, the microstructural characteristics and reaction mechanism of AABFS paste were investigated. The results showed that changes in the mass ratio of sodium hydroxide and blast furnace slag ( m SH / m SL ) have great influence on the performance parameters, including the fluidity, setting time, flexural strength, and compressive strength. Results at the microstructural level indicated that the structure of the AABFS paste specimen prepared at the optimum ratio is more compact and uniform, and the AABFS paste can be applied effectively in road-grouting reinforcement. [ABSTRACT FROM AUTHOR]

Abstract: Conductive hydrogels are a promising class of materials to design bioelectronics for new technological interfaces with human body, which are required to work for a long‐term or under extreme environment. Traditional hydrogels are limited in short‐term usage under room temperature, as it is difficult to retain water under cold or hot environment. Inspired by the antifreezing/antiheating behaviors from nature, and based on mussel chemistry, an adhesive and conductive hydrogel is developed with long‐lasting moisture lock‐in capability and extreme temperature tolerance, which is formed in a binary‐solvent system composed of water and glycerol. Polydopamine (PDA)‐decorated carbon nanotubes (CNTs) are incorporated into the hydrogel, which assign conductivity to the hydrogel and serve as nanoreinforcements to enhance the mechanical properties of the hydrogel. The catechol groups on PDA and viscous glycerol endow the hydrogel with high tissue adhesiveness. Particularly, the hydrogel is thermal tolerant to maintain all the properties under extreme wide tempreature spectrum (−20 or 60 °C) or stored for a long term. In summary, this mussel‐inspired hydrogel is a promising material for self‐adhesive bioelectronics to detect biosignals in cold or hot environments, and also as a dressing to protect skin from injuries related to frostbites or burns. [ABSTRACT FROM AUTHOR]

In the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) project, the fiber should precisely align with the celestial target to obtain the spectrum of the star, and the position accuracy of the fiber in the focal plane directly affects the spectral quality. LAMOST uses photogrammetry to acquire the actual position of the fiber. However, the fiber view camera system without precise internal control points in the focal plane negatively affects measurement precision. To solve this problem, we propose a fiber position measurement method based on the external planar target (EPT) that replaces the internal control points with the external control points; multiview reconstruction and bundle adjustment with additional position constraints are used to calculate the position of the fibers. The validity of the measurement method is verified by the simulation and experiment. The preliminary results show that the method has good stability and the measurement accuracy of the fibers can reach 20 μm. Because the external control points are distributed on the EPT plane, the assembly error of the EPT and focal plane does not affect the measurement accuracy. Therefore, the proposed method can achieve precision measurement under nonprecision installation conditions. [ABSTRACT FROM AUTHOR]

Objective. To investigate the improvement of cognitive function and inflammatory response in perimenopausal patients with MCI by kidney-tonifying, blood-activating, and mind-nourishing. Methods. 80 perimenopausal patients with MCI who met the diagnostic criteria were divided into a therapy group (n = 40) and a control group (n = 40) according to the treatment method. The control group was given nimodipine (Bayer Pharmaceuticals) 30 mg, 3 times/day orally, while the therapy group was given a decoction of self-prepared Ningshen prescription on the top of the control group (glossy privet fruit, mulberry, aizoon stonecrop, dan-shen root, tuber fleeceflower stem, cyperus rotundus, citron). Patients in the 2 groups were assessed on the MocA scale, ADL scale, and TCM symptom score before and after 2 months of treatment, respectively, to observe whether there was any change in the scale scores and in the levels of inflammatory factors (hs-CRP, Hcy, and IL-1β) Pre- and posttherapy in the 2 groups. Observe the improvement of clinical symptoms and their safety in both groups (liver and kidney function indicators such as ALT, AST and Cr, dizziness, headache, decrease in blood pressure, flushing, and gastrointestinal reactions). Results. The efficacy of the therapy group was better than that of the control group; the MocA scale and ADL scale scores improved and the TCM symptom score decreased in both groups posttherapy, with the MocA scale and ADL scale scores improving more and the TCM symptom score decreasing more in the therapy group compared with the control group during the same period (p < 0.05). The serum levels of hs-CRP, Hcy, and IL-1β decreased in both groups posttherapy, with the serum levels of hs-CRP, Hcy, and IL-1β decreasing more in the therapy group compared to the control group during the same period (p < 0.05). The difference in adverse events between the two groups was not statistically significant when compared by a chi-square test (p > 0.05). The differences in ALT, AST, and Cr levels between the control group and the treatment group before and after treatment were not significant (p > 0.05). Conclusion. Ning Shen prescription can effectively prevent the continued development of cognitive dysfunction in perimenopausal patients with MCI, delay its natural course, and can improve the patients' ability to perform daily activities and improve their TCM symptoms. [ABSTRACT FROM AUTHOR]

• Acute rejection response is still the leading cause of liver graft loss and failure. • We uncovered an immune regulatory role of X-box binding protein 1 (XBP1) on the immune function of Kupffer cells (KCs) which influence the immune response after liver transplantation. • XBP1s protected rat's liver allograft via JAK-STAT mediated KCs polarization. Polarized kupffer cells (KCs) influence the immune response after liver transplantation. We report an undiscovered immune regulatory role of X-box binding protein 1 (XBP1) on immune function of kupffer cells (KCs). Acute rejection model using rats. We found that suppression of XBP1s in lipopolysaccharide (LPS) -activated KCs could increase the expression of arginase-1 (Arg-1) and CD204 but also decrease the expression levels of MHC-II and CD40 and shift the phenotype markers of KCs toward M2 via the janus kinase (JAK) 3- Signal Transducer And Activator Of Transcription (STAT) 6 pathway, presenting an immunosuppressive function by enhancing anti-inflammatory cytokine secretion and accelerating apoptosis of activated T cells. XBP1s over-expression in KCs shift the phenotype markers on KCs towards M1 via the JAK1-STAT1 pathway and have shown a strong pro-inflammatory property. Down-regulation of XBP1s in KCs changed the phenotype and cytokine secretion profile towards M2 and markedly protected the function and structure of allograft liver, prolonging the recipient's survival compared with control and normal saline groups in rats. Our findings reveal a novel regulatory mechanism of XBP1 in an induced immuno-suppressive state to protect rat's liver allograft via JAK-STAT mediated KCs polarization. [ABSTRACT FROM AUTHOR]

Background. Liver ischaemia-reperfusion injury (IRI) remains a problem in liver transplantation. Interleukin-4 (IL-4) has been found to reduce liver IRI, but the exact mechanism remains unclear. Methods. Donor livers were infused with recombinant IL-4 or normal saline during cold storage, and the hepatocellular apoptosis and the inflammatory response were detected. The effect of IL-4 treatment on Kupffer cells (KCs) polarization and expression of the STAT6-JMJD3 pathway was evaluated in vivo and in vitro. KCs in donor livers were depleted by clodronate liposome treatment or JMJD3 was inhibited by GSK-J4 before liver transplantation to determine whether the protective effect of IL-4 treatment was dependent on KCs. Results. IL-4 treatment decreased sALT and sAST levels and alleviated hepatocellular apoptosis and inflammation at 6 h after liver transplantation. IL-4 treatment induced KCs alternatively activated (M2) polarization in vitro and in vivo, and the expression of STAT6 and JMJD3 was increased. JMJD3 knockdown abolished KCs M2 polarization and reduced the antiapoptotic and anti-inflammatory effects induced by IL-4 treatment in vitro. In addition, the protection of IL-4 treatment against IRI induced by liver transplantation was significantly reduced after the depletion of KCs or the inhibition of JMJD3 in donor livers. Conclusions. IL-4 treatment-induced KCs M2 polarization was dependent on the STAT6-JMJD3 pathway and protected liver grafts from IRI after liver transplantation. [ABSTRACT FROM AUTHOR]

Fluoridated hydroxyapatite (FHA) [Ca 10 (PO 4) 6 F x (OH) 2−x , x = 0–2] is believed to be a promising calcium phosphate (CaP) to replace pure hydroxyapatite (HA) for next-generation implants, owing to its better biocompatibility, higher antibacterial activity, and lower solubility. Notably, the shape and size of the CaP crystals play key roles in their performance and can influence their applications. One-dimensional (1D) FHA nanorods are important CaP materials which have been widely used in regenerative medicine applications such as restorative dentistry. Unfortunately, the traditional synthesis methods for FHA nanorods either employ surfactants or take a relatively long time. In this study, we aimed to propose a facile synthesis route to fabricate FHA nanorods without any surfactants using an electrochemical deposition method for the first time. This study focused on preparing FHA nanorods without the assistance of any surfactant, unlike the traditional synthesis methods, to avoid chemical impurities. FHA nanorods with lengths of 124–2606 nm, diameters of 28–211 nm, and aspect ratios of 4.4–21.8 were synthesized using the electrochemical method, followed by a heat treatment. For the as-synthesized FHA nanorods, the Ca/P ratio was 1.60 and the atomic concentration of F was 2.06 at.%. An ultrastructure examination revealed that each FHA nanorod possessed long-range order, good crystallinity, and a defect-free lattice with a certain crystallographic plane orientation along the whole rod. In short, we propose a novel, surfactant-free, cost-saving, and more efficient route to synthesize FHA nanorods which can be widely applied in multiple biomedical applications, including drug delivery, bone repair, and restorative dentistry. [ABSTRACT FROM AUTHOR]

[Display omitted] • A cascade model chain suitable for the risk of future DWAA events is proposed. • Evolution characteristics of DWAA in the future period of YRB are revealed. • Severity of DWAA events in far-future is greater than that in the near-future. • Extreme precipitation events have strong synchronization with DWAA events. At present, many studies have investigated the evolution characteristics, frequency estimation techniques, and prediction of droughts and floods, but a comprehensive understanding of the spatiotemporal evolution law and joint risk of these two composite extreme events is still lacking. The synergistic effect of dry and wet abrupt alternation (DWAA) events has more significant consequences than a single drought and flood event, and these events have a considerable impact on agriculture, ecology, and economy. Furthermore, owing to the intensification of global warming and climate change, the potential synchronisation between DWAA events and extreme precipitation in the future requires special attention. Therefore, it is necessary to establish a reliable framework to analyse the evolution characteristics and risks of composite extreme events (DWAA). In this study, a cascade modelling chain comprising climate model downscaling, non-uniform bias-correction technique, and model integration was developed to study the spatiotemporal evolution characteristics and combined risk impact of DWAA events. The proposed methodology was applied to the Yellow River Basin (YRB) in the historical period (1960–2014, Hist) and the future period (2021–2060, FUT1; and 2061–2100, FUT2) under the Shared Socioeconomic Pathway (SSP) 3–7.0 and 5–8.5 scenarios. The results show that: (1) The constructed cascade modelling chain has high simulation accuracy for precipitation, and can be used to analyse future DWAA events. (2) Considering the precipitation characteristics under SSP3-7.0 and SSP5-8.5 scenarios, the precipitation increases slightly in the near future FUT1 (about 5–10%), and increases significantly in the far future FUT2 (about 10–70%). (3) Following either scenario, the frequency of DWAA events is expected to decrease in the future compared to that in the Hist, but the average intensity is expected to increase compared to that in the Hist. (4) The joint risk of the impact area and intensity of future DWAA events of FUT2 is greater than that of FUT1. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the three-dimensional (3-D) non-linear dynamics of inclined supported pipes conveying fluid with motion constraints are investigated. The motion constraints are modeled by an array of four and an array of two cubic non-linear springs. The spring forces are incorporated into the equations of motion via the method of virtual work. The equations of motion, obtained from Hamilton's principle, are discretized into 18 coupled non-linear ordinary differential equations using Galerkin's method, and solved numerically via Houbolts's method and Newton-Raphson iterative technique. Bifurcation diagram and oscillation trajectories are plotted to show the characteristics of some typical motions. The effect of system parameters, such as the inclination angel and spring stiffness, on the system dynamics is investigated. [ABSTRACT FROM AUTHOR]

Abstract In the exploration and development of deep reservoir resources, well kick often occurs during drilling. The occurrence of well kick can change the flowing state and the various properties of the drilling fluid, which can have a very important impact on the wellbore temperature distribution. Based on the actual situation in the drilling process, the wellbore and formation heat transfer model in the case of normal circulation and in the case of well kick in the open-hole formation was established. The model was discretized by using the finite volume method and solved with under-relaxation iterative method. By comparing with previous research results, the validity of the model was established. Compared with the condition of normal circulation, the occurrence of well kick significantly changes the wellbore temperature distribution and has an important influence on the temperature difference profile and formation radial temperature distribution. Sensitivity factors that affected the wellbore temperature distribution were analyzed. Based on the difference in wellbore temperature distribution under normal circulation conditions and well kick conditions, this paper proposes a new method to detect the occurrence of well kick by monitoring the annulus temperature change. The new method can provide guidance for the well control operations and drilling operations. Highlights • Transient temperature model of wellbore in well-kick condition was established. • Temperature distribution of wellbore and formation was analyzed. • Sensitivity factors affected the wellbore temperature distribution were analyzed. • A new method to detect the occurrence of well-kick was proposed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Sr, Zn, and Sr/Zn-codoped HA porous scaffolds were prepared by combing an ion-exchange and a foaming method. • The ion-exchange method realized multi-ion doping of HA while protecting the intrinsic physiochemical and bioactive properties of HA. • A joint experimental-computational investigation proved doping of Sr/Zn into HA; doped HA have high crystallinity. • The Ca(II) substitution was more favored in the Sr and Zn-doped HA. • Sr/Zn codoped HA scaffolds exhibited both good osteoinductivity and excellent antibacterial properties. Abstract The porous scaffold of hydroxyapatite (HA) is highly promising for application in clinics owing to its interconnected porous structure, excellent mechanical properties, biocompatibility, and biological activity; however, the effectiveness of its antibacterial properties and osteoinductivity limits its wide usage. In the present study, strontium (Sr), zinc (Zn), and Sr/Zn-codoped porous scaffolds of HA were prepared by an ion-exchange method and a foaming method. The results based on the density functional theory (DFT) and experimental methods suggested that Sr and Zn were successfully doped into the HA lattice structure, thereby changing the lattice parameters of HA. Sr-doped, Zn-doped, and codoped porous HA scaffolds promoted the proliferation of bone marrow stromal cells (BMSCs), and Sr-doped and codoped porous HA scaffolds promoted BMSC differentiation. In addition, Zn-doped and codoped porous HA scaffolds exhibited excellent antibacterial properties. In short, the codoped HA porous scaffolds, prepared using the simple, facile, and mild ion-exchange, and foaming methods, had good biocompatibility, osteoinductivity, and antibacterial properties, which could effectively inhibit microbial infection and promote bone tissue regeneration in the process of bone repair. Moreover, they are hopeful to be good bone replacement material in clinical application. [ABSTRACT FROM AUTHOR]

Abstract In the exploration and development of deep reservoir resources, the occurrence of well kick will have a very important impact on wellbore temperature distribution during circulation. This study aims to investigate the wellbore temperature distribution during circulation when well kick occurs in a continuous formation from the bottom-hole. A transient temperature model was established by the first law of thermodynamics. The finite volume method was used to discretize the model and the under-relaxation iterative method was used for numerical calculation. The validity of the model has been verified by the previous typical models and actual measured temperatures. The calculation results showed that the highest temperature of annulus fluid was at the bottom-hole and annulus fluid temperature increased as the formation high-temperature fluid continuously enters the annulus when well kick occurred. The occurrence of well kick led to a significant increase in outlet fluid temperature and bottom-hole fluid temperature. The occurrence of well kick changed the formation radial temperature distribution and the temperature difference distribution between the annulus fluid and the drilling fluid inside the drill string. The flow rate of the well kick and the location of the well kick occurred also had an important impact on wellbore temperature distribution. Highlights • Transient temperature model of wellbore in well-kick condition was established. • The finite volume method was used to discretize the model. • Temperature distribution of wellbore and formation was analyzed. • Well-kick seriously affects the temperature distribution of wellbore and stratum. [ABSTRACT FROM AUTHOR]

Abstract This study addresses the difficulty in systematically and scientifically evaluating the comprehensive performance of low-carbon modified asphalt. Sixteen technical indexes were selected as evaluation indicators. The corresponding weight of each evaluation index was determined by the coefficient of variation method. The fundamental performance, environmental protection effect, and economic effect of low-carbon modified asphalt were analyzed systematically. A comprehensive performance evaluation system for low-carbon modified asphalt was established based on the efficacy coefficient method. Low-carbon modified asphalt using tourmaline anion powder was selected as an example for inspection. Its comprehensive performance was evaluated, and the optimal content of tourmaline anion powder was determined. The results showed that the comprehensive performance evaluation of low-carbon modified asphalt using tourmaline anion powder reflects well the actual situation, meaning that a comprehensive performance evaluation system for low-carbon modified asphalt based on the efficacy coefficient method is relatively reliable and useful. This study lays the foundation for the comprehensive performance evaluation and further application of low-carbon modified asphalt. Graphical abstract Image 1 Highlights • Sixteen evaluation indexes. • Comprehensive performance evaluation system for low-carbon asphalt. • Low-carbon asphalt using tourmaline anion powder. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the coupled axial and transverse non-linear vibrations of a simply supported pipe, subjected to motion-limiting constraints, conveying pulsating fluid are investigated. The equations of motion are discretized into a set of coupled ordinary differential equations via Galerkin's method, which are then solved using Houbolt's method combined with Newton-Raphson iterative technique. The bifurcation diagrams are constructed to present the global dynamics of the system. Phase-plane portraits, Poincaré maps and power spectrum diagrams are plotted to show the characteristics of some typical motions, such as quasi-periodic and chaotic motions. Finally, the influence of axial motion on the system dynamics is investigated. [ABSTRACT FROM AUTHOR]

Curcumin shows protective effects on various diseases due to its anti-inflammatory and anti-oxidative functions; however, its effect on organ transplantation has not been fully elucidated. To understand its role in liver ischemia/reperfusion (I/R) injury, we studied its impact on orthotopic liver transplantation (OLT) and Kupffer cells (KCs) polarization and its underlying mechanisms. We first investigated the reactive oxygen species (ROS) accumulation and cytokines profile of KCs, intracellular ROS and the mRNA level of pro-inflammatory cytokines were downregulated while the mRNA level of anti-inflammatory cytokine was upregulated by the pretreatment of Curcumin; Then the liver injury was detected by histopathological examination and liver function. Pretreatment with Curcumin significantly alleviated liver injury while improving liver function and overall post-transplantation survival compared with the control groups. The Western blotting showed that Curcumin inhibited the function of KCs via down-regulating the nuclear factor κb (NF-κb) signaling pathway by activating peroxisome proliferator-activated receptor γ (PPARγ) and flow cytometry revealed that Curcumin suppressed pro-inflammatory phenotype (M1) of KCs while promoting its anti-inflammatory phenotype (M2) polarization. These results showed that Curcumin may exert positive effects on I/R injury after OLT through activating PPARγ by inhibiting the activation of NF-κb pathway and remodeling the polarization of KCs. This may reveal a potential therapy for I/R injury after liver transplantation. [ABSTRACT FROM AUTHOR]

Objectives: Icariin (ICA) is a bioactive flavonoid with renal protective actions. This study investigated the effects of ICA on renal injury, inflammation, oxidative damage, apoptosis, and survival in a mouse model of cecal ligation and perforation (CLP)-induced sepsis. Methods: Sepsis was induced by CLP. Mice were treated with ICA (30 or 60 mg/kg) for 3 days before CLP. Renal functions, inflammatory responses, oxidative damage, histological changes, apoptosis, and vascular permeability were examined. The effects of ICA on CLP-induced expression of renal nuclear factor-κB (NF-κB), cleaved caspase-3, Bax, and Bcl-2 were evaluated. Results: Mice in the CLP group had a low survival rate and increases in blood urea nitrogen and creatinine levels, proinflammatory cytokine levels, oxidative damage, apoptosis, and vascular permeability. These renal changes were dramatically improved by ICA treatment, especially in the 60 mg/kg ICA group. The detection of molecules involved in the inflammation and apoptosis of the kidney indicated that ICA reduced expression of NF-κB, cleaved caspase-3, and Bax but enhanced expression of Bcl-2. Conclusion: ICA improves CLP-induced mortality and acute kidney injury by inhibiting renal oxidant damage, inflammatory responses, apoptosis, and vascular permeability. [ABSTRACT FROM AUTHOR]

• A method of regional non-stationary flood frequency analysis is proposed. • The index incorporates climatic and reservoir factors as covariates. • MRI is more suitable for non-stationary flood frequency analysis. • The prediction period of flood frequency analysis is extended. Global climate change and reservoir regulations can alter the natural flow of rivers. Influenced by these two drivers, flood sequences may no longer satisfy the assumption of stationary, thereby making it difficult to accurately analysis flood frequency and to design water conservancy projects. Therefore, it is of great significance to analyse the non-stationary frequency of flood sequences in a changing environment. In this study, we proposed a method for conducting nonstationary flood frequency analysis caused by cascade reservoirs as well as the low-frequency climate indices. The proposed non-stationary model 2, with the explanatory variables of climate indices and modified reservoir index (MRI), was compared with the traditional stationary model and the widely used non-stationary model 1 with time as the explanatory variable. The study was conducted at six hydrological stations in the main stream and tributaries of the upper reaches of the Yangtze River in China (considered as the Three Gorges Reservoir Area). The results of the generalized additive model for location, scale and shape (GAMLSS) showed that the Akaike information criterion and Bayesian information criterion values of the proposed non-stationary model method 2 are smaller than those of the two comparison models. When the low-frequency South Oscillation Index is high or the Arctic Oscillation and North Pacific Oscillation are low, the stationary model underestimates the design value of flood quantiles compared with the non-stationary model 2. Compared with the non-stationary model 1, the MRI and low-frequency climate indices as the explanatory variables in model 2 can better describe the non-stationary characteristics of flood frequency and amplitude. In addition, the non-stationary model considering external physical factors can provide better prediction of future design flood compared with two traditional models. [ABSTRACT FROM AUTHOR]

• Four daily precipitation datasets were integrated based on the modifiable Bayesian model averaging (BMA) framework. • Seven blended precipitation products were generated by considering different inputs. • Some BMA products outperformed the representative merged product, MSWEP. • Impacts of the ensemble members on BMA predictions were quantitatively analyzed. Selection of the number and which of multisource precipitation datasets is crucially important for precipitation fusion. Considering the effects of different inputs, this study proposes a new framework based on the Bayesian model averaging (BMA) algorithm to integrate precipitation information from gauge-based analysis CPC, reanalysis-derived dataset ERA5, and satellite-retrieval products IMERG-E and GSMaP-RT. The BMA weights were optimized for the period 2001–2010 using daily measurements and then applied to the period 2011–2015 for model validation. Seven BMA-merged precipitation products (i.e., MCE, MCI, MCG, MCEI, MCEG, MCIG, and MCEIG) were thoroughly evaluated across mainland China and then compared against the state-of-the-art ensemble-based product, MSWEP. The results indicate that the BMA predictions performed substantially better than the reanalysis and satellite precipitation datasets in both daily statistics and seasonal analyses. MCE, MCI, and MCEG demonstrated better performances relative to CPC in terms of individual metrics. Moreover, MCI, MCG, and MCEI generally outperformed MSWEP over the entire study area, particularly in local regions, such as southwestern China and the eastern Tibetan Plateau. During Typhoon Rammasun in 2014, MCG and MCEG provided greater detail for heavy rainfall events than the four ensemble members and the MSWEP product. Thus, the performance of the BMA predictions exhibited evident differences because of various input sources. CPC was the major internal influencing factor with the highest weight score. Meanwhile, the increased-input CPC dataset into the BMA-based schemes exerted a significant influence on the precipitation estimates, which markedly facilitated the performance improvement of the fusion model, and its improved degree (greater than 14 %) was obtained using a 'changed-initial' comparison method. Our results demonstrate that the developed modifiable BMA framework is useful for analyzing the impacts of ensemble members on BMA predictions and suggests that it is considerate in the use of different input sources for generating ensemble-based precipitation products. [ABSTRACT FROM AUTHOR]

The effects of different helical strake coverage on the vortex-induced vibration (VIV) of a model flexible riser were studied experimentally, with the aim of further improving the understanding of VIV responses. Uniform and linearly sheared currents were simulated to study response parameters such as non-dimensional displacement, fatigue damage, suppression efficiency, and the comprehensive evaluation is further studied. Test results of the bare model for a uniform current showed that the behavior of both the standing wave and traveling wave dominated VIV displacement. However, for a linearly sheared current, traveling wave behavior dominated VIV displacement in the high-velocity range. The results of the straked model tests indicated that the response was strongly dependent upon the amount of coverage of helical strakes. The flexible riser with 75% strake coverage gave the best comprehensive evaluation in a uniform current, and 50% strake coverage gave the best comprehensive evaluation in a linearly sheared current. [ABSTRACT FROM AUTHOR]

This study focused on improving the performance of the near real-time Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) Early Run (IMERG-E) product based on a newly developed bias-correction scheme, LSCDF. The LSCDF was established by integrating the mean-based Linear Scaling (LS) and quantile-mapping Cumulative Distribution Function (CDF) matching approaches. The daily updating gauge-based precipitation data from the Climate Prediction Center (CPC) unified analysis were used as the benchmark for bias correction. The IMERG-E bias-corrected precipitation data were evaluated against the daily ground measurements from 807 meteorological stations across mainland China and compared with the raw IMERG-E and IMERG Final Run (IMERG-F; research-level with gauge calibration) retrievals. Evaluation results for the period 2015 to 2017 showed that the LSCDF method effectively improves near real-time IMERG-E precipitation estimates at the daily scale. The bias-corrected IMERG-E precipitation estimates were in significantly better agreement with ground measurements than the original IMERG-E at the point-daily resolutions, with the correlation coefficient increasing from 0.66 to 0.77, relative bias decreasing from 11.1% to −3.1%, and root-mean-square error dropping from 6 mm/day to 4.39 mm/day. In addition, the bias-corrected IMERG-E was apparently superior to IMERG-E in detecting precipitation events at various intensity levels including small, light, moderate, and heavy precipitation. Although IMERG-E tended to significantly underestimate or overestimate precipitation during three typical typhoons, the bias-corrected IMERG-E can match the rainfall spatial distributions well, demonstrating a considerable capability in capturing the extreme precipitation. Generally, the bias-corrected IMERG-E featured a substantial improvement over the original IMERG-E, and it even exhibited a more satisfactory overall performance than the research-level gauge-calibrated IMERG-F product. Our study demonstrates that the bias-correction method LSCDF can improve the accuracy of satellite precipitation products to benefit the near real-time application of satellite products for natural hazards. • The LSCDF method was developed by combining linear scaling (LS) and cumulative distribution function (CDF) matching. • LSCDF was used for bias correction of daily satellite precipitation data (IMERG-E). • The LSCDF significantly improved the accuracy of satellite precipitation estimates. • The bias-correction method, LSCDF, can be used in near real-time applications. [ABSTRACT FROM AUTHOR]

In this study, a comprehensive evaluation of the reliability of seventeen satellite-, reanalysis-, and gauge-based precipitation products (i.e., IMERG-F, GSMaP-G, TMPA 3B42, CMORPH-CRT, PERSIANN-CDR, CHIRPS, IMERG-E, IMERG-L, GSMaP-RT, TMPA-RT, PERSIANN-RT, ERA5, ERA-Interim, MERRA2, GPCC, CPC, and CRU) was conducted for drought monitoring from June 2000 to December 2019 over mainland China. The girded China monthly Precipitation Analysis Product (CPAP) with a dense station network was used as the benchmark observed precipitation data. The Standardized Precipitation Index (SPI) was used as a drought monitoring tool. The comprehensive evaluation procedures were implemented by a monthly precipitation evaluation, various timescales SPI verification, and typical drought event analysis. The results indicated that the performance of per precipitation product is in accordance with the generally higher monthly accuracy in eastern China than that in western China. The post-process satellite precipitation products, particularly bias-adjusted GPM-based products, i.e., the IMERG-F and GSMaP-G, are significantly better at detecting the monthly precipitation than the reanalysis (ERA5 and ERA-Interim), and near real-time satellite precipitation datasets. The best performances are observed for MERRA2 from reanalysis-based precipitation datasets, and GPCC from gauge-based precipitation products, for both precipitation estimation and drought monitoring. Regarding drought monitoring, the performance ranking of most precipitation products is basically consistent with monthly precipitation estimation. The SPI behaviors based on the bias-adjusted GPM-based products have inferior performance than those in MERRA2 and GPCC at the continental scale. Nevertheless, some discrepancies exist in the reliability level of drought detection in sub-regions and multi-timescales. Integrally, the IMERG-F is evaluated to be the most ideal precipitation data among the seventeen precipitation products for drought monitoring in eastern and southwest China. However, in comparison to the GPCC performance, the accuracy of satellite precipitation products should be further improved in the Xinjiang and Tibet Plateau regions. The outcomes of this study will provide valuable insights into the drought monitoring by using multi-sources open access precipitation products across mainland China. • 17 precipitation products reliability were analyzed over mainland China. • Reanalysis- and gauge-based datasets were used to reveal the performance level of satellite-estimated drought. • IMERG-F is the most suitable dataset for drought research in eastern and southwest China [ABSTRACT FROM AUTHOR]

• A comprehensive framework for quantifying the climatic and anthropogenic influences on river hydrological health is proposed. • Human activities significantly aggravate the degradation of river hydrological health for the studied catchment. • Widespread artificial water withdrawal and reservoir operation are the two crucial human activities. • Adequate rainfall maintains the river hydrological health at a good status in the 1990 s. Climate change and human activities have together altered the river hydrological regime and consequently threatened the health of river ecosystems. Quantifying the impact of climate change and human activities on river hydrological health regimes is essential for water resource management and river ecology protection. Although previous studies have analysed the hydrologic alterations using some indicators, separating effects of climate change and human activities on river hydrological health is needed for developing adaptive measures to protect the ecosystem of river basins. In this study, a comprehensive assessment framework for quantifying climatic and anthropogenic influences on river hydrological health variation was proposed. The framework consists of the following steps: (1) the reconstruction of natural river streamflow using the variable infiltration capacity (VIC) hydrological model, (2) calculation of river hydrological health through the ecological flow threshold method, and (3) quantification of the impacts of climate change and human activities on river hydrological health using the 'observed–simulated' comparison approach. The semi-arid Laohahe Basin in northern China, which consists of three human-influenced catchments (Taipingzhuang, Chifeng, and Xinglongpo) and one natural catchment (Xiquan), was selected as the case study area. The case study demonstrated that the proposed procedure is efficient in quantifying climatic and anthropogenic influences on river hydrological health. The results revealed that the hydrological health level has significantly declined in the three human-influenced catchments for the human-influenced period (1980–2016), particularly in the 2000 s and 2010 s, where it degraded much more severely. Whereas, the relatively adequate rainfall in the 1990 s maintained the river hydrological health at a good status. The quantitative evaluation showed that human activities were the main driving factors for the hydrological health degradation during the whole human-influenced period, with contributions of 80.8%, 91.9%, and 86.0% for the Taipingzhuang, Chifeng, and Xinglongpo catchments, respectively. Widespread artificial water withdrawal and reservoir operation were the two crucial human activities that caused the degradation of river hydrological health for the studied catchment. The proposed procedure and findings of this study not only help in deeper understanding of the evolutionary characteristics and driving mechanisms of river hydrological health in a changing environment in general, but also provide scientific basis for local water resources management and river ecosystems protection. [ABSTRACT FROM AUTHOR]

In this paper, we comprehensively evaluated the utility of integrated long-term satellite-based precipitation and evapotranspiration products for drought monitoring over mainland China. The latest Integrated Multi-satelliteE Retrievals for Global Precipitation Measurement V06 three Runs precipitation products, i.e., the near real-time Early Run (IMERG-E) and Late Run (IMERG-L) and the post-real time Final Run (IMERG-F), and the Global Land Evaporation Amsterdam Model V3.3a (GLEAM) potential evapotranspiration (PET) products from 2001 to 2017 were considered. The accuracy of IMERG precipitation and GLEAM PET products was first evaluated against observed precipitation and Penman-Monteith method estimated PET, respectively, based on dense meteorological station network. The Standard Precipitation Evapotranspiration Index (SPEI) calculated based on IMERG precipitation and GLEAM PET products (SPEIs, including SPEI E , SPEI L and SPEI F corresponding to IMERG-E, IMERG-L and IMERG-F, respectively) were then validated by using SPEI calculated based on meteorological data (SPEIm) at multiple temporal-spatial scales. Finally, four typical drought events were selected to analyse the ability of SPEIs to characterize the temporal-spatial evolution of drought situations. The results showed that the IMERG-F presents much better performance than IMERG-E and IMERG-L in terms of higher CC and smaller BIAS and RMSE values over mainland China. The GLEAM PET well simulated the change trend of reference PET, but generally underestimated reference PET in Northwest China (NW), Xinjiang (XJ) and Qinghai–Tibet plateau (TP). In general, the performances of SPEIs over eastern China and Southwest China (SW) were significantly superior to their performances in the NW, XJ, and TP regions. Even though the SPEI F performed the best, the SPEI E and SPEI L also performed reasonably well in some specific regions. SPEIs can well capture the temporal process and reasonably reflect the spatial characteristics for four typical drought events. It is thus highlighted that the latest IMERG precipitation (especially for IMERG-F) and GLEAM PET products could be used as alternative data sources for comprehensive drought monitoring, on account of the water balance principle over mainland China, particularly in eastern China and SW China. The outcomes of this study will provide valuable references for drought monitoring by integration of multi-source remote-sensing datasets in the GPM era. • The utility of integrated IMERG precipitation and GLEAM PET for drought monitoring was evaluated over mainland China. • SPEIs based on IMERG precipitation and GLEAM PET were validated at multiple spatial and temporal scales over mainland China. • IMERG precipitation and GLEAM PET show great potential for drought monitoring over eastern China and Southwest China. • SPEIs can well capture the temporal process and reasonably reflect the spatial characteristics for typical drought events. [ABSTRACT FROM AUTHOR]

Titanium has been widely used in medical implants for hard tissue replacements. Nevertheless, the bioinert innate oxide layer on the titanium implant surface usually makes the implant fail to osseointegrate with the surrounding tissue after surgery. To improve the bioactivity of titanium implants, the deposition of calcium phosphate (CaP) coatings attracts much research interest owing to the excellent bioactivity and biocompatibility of CaP. This work successfully developed a promising synthetic method to prepare uniform fluoridated CaP coatings with ultrathin thicknesses (∼170 nm) and desired phases on acid etched pure titanium (AETi) substrates. A dense ultrathin coating with a dominant phase of fluoridated amorphous CaP (FACP) was obtained by an electrochemical deposition method in galvanostatic mode. After a heat treatment at 600 °C for 3 h in a humid atmosphere, the as-prepared coating was transformed to a coating with a dominant phase of fluoridated hydroxyapatite (FHA). Additionally, the dominant phase of the coating could be transformed from FACP to α-tricalcium phosphate (α-TCP) by a heat treatment at 800 °C for 3 h. Unlike previously reported fluoridated CaP coatings with thicknesses of around several micrometers, the ultrathin thickness could potentially enhance the adhesive strength and ductility of coating. Notably, the fluorine incorporation in the coating could bring in additional benefits such as lower solubility, higher antibacterial activity, and higher adhesive strength. Electrochemical deposition associated with post heat treatment could obtain fluoridated CaP coatings with different desired phases in a controllable manner, which is very important since CaPs with different phases possess different properties and may be suitable for different biomedical applications. This study proposed a promising, simple, and low-cost method which can endow complex-shaped titanium implants with better bioactivity for dental and orthopedic applications. • Unlike previously reported fluoridated CaP coatings with thicknesses of around several micrometers, the ultrathin thickness (∼170 nm) could potentially enhance the adhesive strength and ductility of coating. • The fluorine incorporation in the coating could bring additional benefits such as lower solubility, higher antibacterial activity, and higher adhesive strength. • Electrochemical deposition associated with post heat treatment could obtain fluoridated CaP coatings with different desired phases in a controllable manner, which is very important since CaPs with different phases possess different properties and may be suitable for different biomedical applications. • Proposed a promising, simple, and lower-cost route to endow complex-shaped titanium implants with better bioactivity, which could be widely applied in dental and orthopedic applications. [ABSTRACT FROM AUTHOR]

This study evaluated the suitability of the latest retrospective Integrated Multi-satellitE Retrievals for Global Precipitation Measurement V06 (IMERG) Final Run product with a relatively long period (beginning from June 2000) for drought monitoring over mainland China. First, the accuracy of IMERG was evaluated by using observed precipitation data from 807 meteorological stations at multiple temporal (daily, monthly, and yearly) and spatial (pointed and regional) scales. Second, the IMERG-based standardized precipitation index (SPI) was validated and analyzed through statistical indicators. Third, a light–extreme–light drought-event process was adopted as the case study to dissect the latent performance of IMERG-based SPI in capturing the spatiotemporal variation of drought events. Our results demonstrated a sufficient consistency and small error of the IMERG precipitation data against the gauge observations with the regional mean correlation coefficient (CC) at the daily (0.7), monthly (0.93), and annual (0.86) scales for mainland China. The IMERG possessed a strong capacity for estimating intra-annual precipitation changes; especially, it performed well at the monthly scale. There was a strong agreement between the IMERG-based SPI values and gauge-based SPI values for drought monitoring in most regions in China (with CCs above 0.8). In contrast, there was a comparatively poorer capability and notably higher heterogeneity in the Xinjiang and Qinghai-Tibet Plateau regions with more widely varying statistical metrics. The IMERG featured the advantage of satisfactory spatiotemporal accuracy in terms of depicting the onset and extinction of representative drought disasters for specific consecutive months. Furthermore, the IMERG has obvious drought monitoring abilities, which was also complemented when compared with the Precipitation Estimation from the Remotely Sensed Information using Artificial Neural Networks Climate Data Record (PERSIANN-CDR), Climate Hazards Group Infrared Precipitation with Stations (CHIRPS), and Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis (TMPA) 3B42V7. The outcomes of this study demonstrate that the retrospective IMERG can provide a more competent data source and potential opportunity for better drought monitoring utility across mainland China, particularly for eastern China. [ABSTRACT FROM AUTHOR]

Recently, the cicada-inspired nanostructured surfaces have attracted much interest because they possess remarkable bactericidal ability. However, Gram-positive bacteria are less damageable by the nanopillar structure of a cicada wing surface compared to Gram-negative species. To overcome this shortcoming, fluoridated hydroxyapatite (FHA) is employed owing to its effective antibacterial ability against both Gram-negative and Gram-positive bacteria. Here, we design a novel potential antibacterial surface by combining the cicada wing-like nanopillar structure and the FHA together to potentially exert the advantages of physical and chemical antibacterial strategies simultaneously for battling the antibiotic-resistant pathogenic bacteria more effectively. Cicada-inspired FHA nanostructured surfaces have been successfully fabricated on acid-etched titanium (AETi) plates using an electrochemical additive manufacturing (ECAM) method for the first time. The as-prepared FHA nanopillar array consists of close-packed individual nanopillars with diameters, heights, and aspect ratios of ~65–95 nm, ~380–510 nm, and ~4.5–7.5, respectively. The chemical composition of the FHA nanopillar array is similar to that of the Ca 10 (PO 4) 6 (OH)F. Individual FHA nanopillars possess high crystallinity, long-range regularity, and flaw-free lattices with the [0001] orientation. Our new, cost-effective, and time-saving method for fabricating cicada-inspired FHA nanostructured surfaces could potentially endow orthopedic and dental implants with enhanced antibacterial performance for biomedical applications. Unlabelled Image • We firstly proposed an electrochemical additive manufacturing method for preparing cicada-inspired nanostructured surfaces. • This promising synthesis method is novel, cost-effective, and time-saving. • This study focused on fabricating nanostructures with bioactive and biocompatible fluoridated hydroxyapatite pioneeringly. • We designed the biomimetic nanostructures by combining the advantages of physical and chemical antibacterial strategies. • The nanostructures could potentially endow medical implants with more effective non-antibiotic antibacterial activity. [ABSTRACT FROM AUTHOR]

The multi-satellite retrieved soil moisture products released from Europe Space Agency's Climate Change Initiative (ESA CCI) program have been widely used in plenty of fields including drought monitoring. In this study, Cumulative Distribution Function (CDF) is applied to match the simulated soil moisture from the Variable Infiltration Capacity (VIC) model for filling the missing records of ESA CCI soil moisture (ESA CCI SM). The weekly Standard Soil Moisture Index (SSI) calculated from ESA CCI SM dataset (ESA CCI SSI) is conducted to monitor the agricultural drought over the Yellow River Basin (YRB) during 2000~2012. The performance of ESA CCI SSI is compared with the Standard Precipitation Index (SPI), the Standard Precipitation Evapotranspiration Index (SPEI), the self-calibrating Palmer Drought Severity Index based on VIC model (VIC_scPDSI) and the anomaly of Normalized Difference Vegetation Index (NDVI). The results show that the interpolated ESA CCI SM is significant (p<0.05) correlated with the observed soil moisture and more than 84% of the girds in the YRB display good correlations with the global reanalysis soil moisture. In terms of drought monitoring (i.e. drought area and drought intensity), ESA CCI SSI presents a similar spatiotemporal pattern with VIC_scPDSI, while exhibits a delayed response to SPI and SPEI significantly. Analysis of the typical drought event in 2002 indicates that ESA CCI SSI could effectively capture the emerge and development process of this event and the drought severity detected by ESA CCI SSI is higher than that of SPI and SPEI. Besides, it is found that spatial characteristics of ESA CCI SSI and the anomaly of NDVI are consistent in some areas of the basin. [ABSTRACT FROM AUTHOR]