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Information on soil hydraulic properties (SHPs) and soil moisture (SM) is essential to understand and model water and energy cycles at terrestrial surfaces. However, information regarding these soil properties in existing datasets is often scarce and inaccurate for high, cold mountainous areas such as the Qinghai-Tibet Plateau (QTP). To help bridge this gap, we have compiled an SHP and SM dataset for the northeastern QTP (a major high, cold mountainous area) using measurements of soil collected at 5 and 25 cm depths from 206 sampling sites, and in-situ observations from 32 SM monitoring stations at 5, 15, 25, 40, and 60 cm depths. We used this dataset to explore large-scale variations (spatial and temporal) in SHPs and SM across the study area. We also evaluated several widely used SHP (soil texture, bulk density, and saturated hydraulic conductivity) and SM datasets derived by remote-sensing methods, reanalysis and data assimilation. Our datasets showed that SM significantly decreases from the southeastern part to the northwestern part in the study area, and SM decreases with increases in depth over 0–70 cm. Moreover, the regional annual SM showed decreased trend from 2014 to 2020 in the study area. Additionally, we detected substantial bias in the currently available large SHP datasets, which do not capture the spatial variability recorded in the in-situ observations. Especially, clay and sand estimates from both HWSD and SoilGrid datasets were significantly overestimated, and silt was significantly underestimated within the depth of 0–30 cm in the study area. We also found that SM values derived from remote sensing datasets fitted the in-situ SM observations better than those derived from the reanalysis data (which had higher bias) and data assimilation (which did not capture the temporal variability of SM). Our findings emphasize the unneglectable bias of the widely-used large-scale SHP datasets, especially for the soil texture data. Thus, an urgent need for large-scale field sampling of SHP in mountainous areas. The in-situ observation dataset presented here provides important information with unprecedented coverage and resolution regarding the SHP variability and long-term SM trends across a large, high, cold mountainous area, thereby enhancing our understanding of water cycles and energy exchange processes over the QTP. [ABSTRACT FROM AUTHOR]

We report planar AlN/GaN resonant tunneling diodes (RTDs) fabricated using a nitrogen ion implantation isolation process on silicon substrates. The active area of AlN/GaN RTDs is defined by nitrogen ion implantation. A planar RTD consists of two different-sized RTDs connected in series, where the larger one acts as a resistor and the performance of the planar RTD is determined by the smaller one. Repeatable and hysteresis-free negative differential resistances without degradation are observed through 500 continuous bidirectional voltage sweeps. The peak current density is 15.5 kA/cm2. The RTD exhibits stable negative differential resistance (NDR), with the peak-to-valley current ratio varying from 1.39 to 1.28 as the temperature increases from 77 to 295 K. This practicable and reproducible ion implantation process is compatible with silicon fabrication technology. It, thus, provides a feasible method for device design of GaN-based RTDs and facilitates the implementation of complex monolithic microwave integrated circuits based on planar III-nitride RTDs on large-size silicon wafers. [ABSTRACT FROM AUTHOR]

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We report repeatable AlN/GaN resonant tunneling diodes (RTDs) grown on a silicon substrate by plasma-assisted molecular-beam epitaxy. The RTDs exhibit stable negative differential resistance without hysteresis at room temperature, where no degradation is observed even after 500 continuous bidirectional sweeps. The peak-to-valley current ratio is 1.36, and the peak current density is 24.38 kA/cm2. When the temperature is changed from 77 to 475 K, the peak current remains almost unchanged and the valley current increases gradually, resulting in a reduced peak-to-valley current ratio from 1.59 to 1.07. Our work softens the material quality constraints on realizing the room-temperature repeatable negative differential resistance and paves the way to low-cost III-nitride-based monolithic and hybrid microwave integrated circuits on large-size silicon wafers. [ABSTRACT FROM AUTHOR]

Vacuolar protein sorting-associated protein 16 homolog (VPS16) is a central member of the VPS core complex (VPS–C) and is reported to function as a tether protein involved in membrane fusion. However, a biological role for VPS16 in tumors remains largely unknown. Herein, we demonstrated that VPS16 was overexpressed in colorectal cancer (CRC) as revealed by qRT-PCR, western blotting, and immunohistochemical analyses. Elevated expression of VPS16 was positively correlated with tumor size and TNM stage, and Kaplan-Meier analysis showed an association between VPS16 and survival in CRC patients. Downregulation of endogenous VPS16 significantly suppressed CRC cell viability both in vitro and vivo; and while our mechanistic analysis showed that VPS16 depletion induced autophagy, but the autophagic flow was deficient as reflected by the inhibition of autolysosomal maturation. Overexpression of VPS16 also mediated oxaliplatin (OX) resistance by promoting the maturation of autolysosomes in CRC. VPS16 may therefore promote cell survival and thus serve as a useful target for cancer therapy in CRC. • VPS16 is highly expressed and was associated with clinicopathological parameters in colorectal cancer patients. • VPS16 is essential for tumor survival in vitro and vivo in colorectal cancer. • Overexpression of VPS16 mediates drug resistance via promotion of autolysosomal maturation. [ABSTRACT FROM AUTHOR]

Vegetation restoration over degraded drylands has considerable climate, carbon and ecosystem benefits, yet its water impacts remain contentious. Previous studies suggest that extra vegetation in drylands could lead to decreased soil moisture and runoff caused by enhanced evapotranspiration. However, these studies ignore important vegetation‐climate feedbacks that can partially offset such negative consequences. Here, we examine how revegetation affects water budgets in China's Loess Plateau, where the world's largest revegetation occurs. Despite increased evapotranspiration, long‐term observations exhibit robust increasing trends (2.76 mm yr−2) of surface water yield over a large swath (82.3%) of the Plateau since revegetation starts. This is mainly caused by increased regional precipitation that outweighs increases in evapotranspiration. Numerical experiments further reveal that the increased precipitation is largely driven by revegetation‐induced enhancement in land‐atmosphere interactions that greatly accelerate local moisture recycling. Our findings highlight the importance of considering vegetation‐climate feedbacks in assessing hydrological responses to large‐scale vegetation changes. Plain Language Summary: Vegetation restoration is one of the most effective ecological engineering measures for ecosystem remediation and climate mitigation, and has been widely implemented across the globe over the past few decades. Previous studies suggest that revegetation could threaten long‐term water sustainability of the Loess Plateau in China, a typical dryland region that has witnessed widespread vegetation restoration over the past two decades, as extra vegetation consumes more water through evapotranspiration, leading to decreased soil moisture and runoff. Here we challenge this conclusion by showing that a large swath of the Loess Plateau has experienced robust upward trends of surface water yield since the start of large‐scale vegetation restoration. This is primarily caused by increased regional precipitation that outpaces the increased evapotranspiration induced by revegetation. Further, we demonstrate that the increase in precipitation is largely driven by enhanced land‐atmosphere interactions that accelerate local moisture recycling following revegetation. Our results suggest that previous offline assessments, which ignore important vegetation‐climate feedbacks, may overstate the threats of revegetation on dryland water resources. These findings provide an important scientific basis for guiding current and future revegetation activities toward sustainable ecosystem development and water resources management. Key Points: Surface water yield generally does not decrease in the Loess Plateau after revegetationFaster increases in regional precipitation outweighs enhenced evapotranspirationRevegetation accelerates the local moisture recycling and contributes to the rainfall increases [ABSTRACT FROM AUTHOR]

Drought indices are hard to balance in terms of versatility (effectiveness for multiple types of drought), flexibility of timescales, and inclusivity (to what extent they include all physical processes). A lack of consistent source data increases the difficulty of quantifying drought. Here, we present a global monthly drought dataset with a spatial resolution of 0.25 ∘ from 1948 to 2010 based on a multitype and multiscalar drought index, the standardized moisture anomaly index incorporating snow dynamics (SZIsnow), driven by systematic fields from an advanced data assimilation system. The proposed SZIsnow dataset includes different physical water–energy processes, especially snow processes. Our evaluation of the dataset demonstrates its ability to distinguish different types of drought across different timescales. Our assessment also indicates that the dataset adequately captures droughts across different spatial scales. The consideration of snow processes improved the capability of SZIsnow , and the improvement is particularly evident over snow-covered high-latitude (e.g., Arctic region) and high-altitude areas (e.g., Tibetan Plateau). We found that 59.66 % of Earth's land area exhibited a drying trend between 1948 and 2010, and the remaining 40.34 % exhibited a wetting trend. Our results also indicate that the SZIsnow dataset can be employed to capture the large-scale drought events that occurred across the world. Our analysis shows there were 525 drought events with an area larger than 500 000 km2 globally during the study period, of which 68.38 % had a duration longer than 6 months. Therefore, this new drought dataset is well suited to monitoring, assessing, and characterizing drought and can serve as a valuable resource for future drought studies. The database is available at http://doi.org/10.5281/zenodo.5627369 (Wu et al., 2021). [ABSTRACT FROM AUTHOR]

Soil hydraulic properties (SHPs) and soil moisture (SM) are fundamental to describing and predicting water and energy cycles at the land surface, and for regulating evapotranspiration, infiltration and runoff. However, information about these soil properties from existing datasets is often scarce and inaccurate for high and cold mountainous areas such as the Qinghai-Tibet Plateau (QTP), which hampers our understanding of hydrological and energy cycle processes over large mountainous areas like the QTP. Based on soil profile data at depths of 5 cm and 25 cm from 238 sampling sites, and on soil data from 32 SM monitoring stations at depths of 5 cm, 15 cm, 25 cm, 40 cm, and 60 cm, we have compiled a SHP and SM dataset for a high and cold mountainous area, Northeastern QTP. We used this dataset to explore the large-scale spatial and temporal variability of SHPs and of SM across the study area. Our evaluation of several existing SHP datasets, SM datasets derived from remote-sensing, reanalysis and data assimilation, showed that SHPs (soil texture, bulk density, and soil saturated hydraulic conductivity) in these datasets are biased, and do not capture the spatial variability recorded in the in-situ observations. When comparing with the in-situ SM observations, the SM product derived from remote-sensing was more reliable than the SM product derived from reanalysis data (which had a higher bias), and than the data assimilation product (which did not capture SM temporal variability). The in situ observation dataset presented here provides unique and important information about the SHP variability and long-term SM trends at a large-scale, high and cold mountainous area, and thus offers opportunity for further understanding of water cycle and energy exchange processes over the QTP. [ABSTRACT FROM AUTHOR]

Multi-frequency multi-bit programmable amplitude modulation (AM) of spoof surface plasmon polaritons (SPPs) is realized at millimeter wave frequencies with interdigital split-ring resonators (SRRs) and In-Ga-Zn-O (IGZO) Schottky diodes. Periodic SRRs on a metal line guide both SRR mode and spoof SPP mode, the former of which rejects the spoof SPP propagation at the SRR resonant frequencies. To actively modulate the amplitude of spoof SPPs, IGZO Schottky diodes are fabricated in the SRR gaps, which continuously re-configure SRRs to metallic loops by applying bias. Interdigital gaps are designed in SRRs to increase the capacitance, thus red shifting the resonant frequencies, which significantly broadens the operation bandwidth of multi-frequency AM. Thus, cascading different kinds of interdigital SRRs with Schottky diodes enables multi-frequency multi-bit AM programmable. As a demonstration, a dual-frequency device was fabricated and characterized, which achieved significant multi-bit AM from −12.5 to −6.2 dB at 34.7 GHz and from −26 to −8.5 dB at 50 GHz independently and showed programmable capability. [ABSTRACT FROM AUTHOR]

The implementation of large-scale vegetation restoration over the Chinese Loess Plateau has achieved clear improvements in vegetation fraction, as evidenced by large areas of slopes and plains being restored to grassland or forest. However, such large-scale vegetation restoration has altered land-atmosphere exchanges of water and energy, as the land surface characteristics have changed. These variations could affect regional climate, especially local precipitation. Quantitatively evaluating this feedback is an important scientific question in hydrometeorology. This study constructs a coupled land-atmosphere model incorporating vegetation dynamics, and analyzes the spatio-temporal changes of different land use types and land surface parameters over the Loess Plateau. By considering the impacts of vegetation restoration on the water-energy cycle and on land-atmosphere interactions, we quantified the feedback effect of vegetation restoration on local precipitation across the Loess Plateau, and discussed the important underlying processes. To achieve a quantitative evaluation, we designed two simulation experiments, comprising a real scenario with vegetation restoration and a hypothetical scenario without vegetation restoration. These enabled a comparison and analysis of the net impact of vegetation restoration on local precipitation. The results show that vegetation restoration had a positive effect on local precipitation over the Loess Plateau. Observations show that precipitation on the Loess Plateau increased significantly, at a rate of 7.84 mm yr−2, from 2000 to 2015. The simulations show that the contribution of large-scale vegetation restoration to the precipitation increase was about 37.4%, while external atmospheric circulation changes beyond the Loess Plateau contributed the other 62.6%. The average annual precipitation under the vegetation restoration scenario over the Loess Plateau was 12.4% higher than that under the scenario without vegetation restoration. The above research results have important theoretical and practical significance for the ecological protection and optimal development of the Loess Plateau, as well as the sustainable management of vegetation restoration. [ABSTRACT FROM AUTHOR]

From 1998 to the present, the Chinese government has implemented numerous large-scale ecological programs to restore ecosystems and improve environmental protection in the agro-pastoral ecotone of northern China (APENC). However, it remains unclear how vegetation restoration modulates intraregional moisture cycles and changes regional water balance. To fill this gap, we first investigated the variation in precipitation (P) from the China Meteorological Forcing Dataset and evapotranspiration (ET) estimated using the Priestley–Taylor Jet Propulsion Laboratory model under two scenarios: dynamic vegetation (DV) and no dynamic vegetation (no-DV). We then used the dynamic recycling model to analyze the changes in precipitation recycling ratio (PRR). Finally, we examined how vegetation restoration modulates intraregional moisture recycling to change the regional water cycle in APENC. Results indicate P increased at an average rate of 4.42 mm yr−2 from 1995 to 2015. ET with DV exhibited a significant increase at a rate of 1.57, 3.58, 1.53, and 1.84 mm yr−2 in the four subregions, respectively, compared with no-DV, and the annual mean PRR values were 10.15%, 9.30%, 11.01%, and 12.76% in the four subregions, and significant increasing trends were found in the APENC during 1995–2015. Further analysis of regional moisture recycling shows that vegetation restoration does not increase local P directly, but has an indirect effect by enhancing moisture recycling process to produce more P by increasing PRR. Our findings show that large-scale ecological restoration programs have a positive effect on local moisture cycle and precipitation. [ABSTRACT FROM AUTHOR]

Maize plays an important role in the Agro‐pastoral ecotone of Northwestern China (APENC), where highly sensitive to changes in climate conditions. However, little is reported on the impacts of climate change on crops in the region. In this study, we used Decision Support System for Agrotechnology Transfer model driven by future climate data from 20 general circulations models under two representative concentration pathways (RCPs: RCP4.5 and RCP8.5) from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to project the effects of climate change on maize yield and water use efficiency (WUE) in eight future time periods (interval: 10 years; from 2020s to 2100s). The model was first calibrated based on field observation for phenology, leaf area index, maize yield and calibrated and evaluated results were reasonably good. Simulated results showed that without and with consideration of CO2 effects, maize yield at the end of the 21st century will decrease by 11.7% and 10.3% under the RCP4.5 scenario, and by 22.1% and 21.2% under the RCP8.5 scenario, respectively. We found that there is a significant correlation between maize yield reduction and warming. Specifically, when the increment of annual average temperature reaches 1°C, the maize yield begins to decrease by 11.27% and 10.8% per 1°C warming without and with consideration of CO2 effects, respectively. Furthermore, high temperature not only affects maize yield but also has a negative effect on WUE. The WUE would change by −8.1% and −18.8% under RCP4.5 and RCP8.5, respectively. But if we consider the effects of CO2, the WUE will improve 1.5% under RCP4.5 and 2.2% under RCP8.5, in comparison to those without consideration of CO2 effects. Overall, future climate warming will seriously affect maize yield and WUE. Although the increase of CO2 concentration is beneficial to raise maize yield and WUE, it is hard to offset the negative effects of the increase in temperature. Besides, change in the planting date can be beneficial for the adaptation of maize to climate change in the APENC. These results will provide comprehensive information to support local policy and decision‐making in agricultural production and water resources management. [ABSTRACT FROM AUTHOR]

Objective. Intracranial aneurysm (IA) is a fatal disease owing to vascular rupture and subarachnoid hemorrhage. Much attention has been given to circular RNAs (circRNAs) because they may be potential biomarkers for many diseases, but their mechanism in the formation of IA remains unknown. Methods. circRNA expression profile analysis of blood samples was conducted between patients with IA and controls. Overall, 235 differentially expressed circRNAs were confirmed between IA patients and the control group. The reliability of the microarray results was demonstrated by quantitative real-time polymerase chain reaction (qRT-PCR). Results. Of 235 differentially expressed genes, 150 were upregulated, while the other 85 were downregulated. Five miRNAs matched to every differential expression of circRNAs, and related MREs were predicted. We performed gene ontology (GO) analysis to identify the functions of their targeted genes, with the terms "Homophilic cell adhesion via plasma membrane adhesion molecules" and "Positive regulation of cellular process" showing the highest fold enrichment. Conclusions. This study demonstrated the role of circRNA expression profiling in the formation of IA and revealed that the mTOR pathway can be a latent therapeutic strategy for IA. [ABSTRACT FROM AUTHOR]

• Sensitivities of drought and pluvial classifications to data length are similar between two standardized indices (SPEI and SZI) that consider water demand. • SZI-based droughts require a longer climate epoch (additional 10 years) to accurately detect extremes in South Africa, South Asia, Oceania compared to pluvials. • Droughts and pluvials require at least 40-year time series to accurately detect around 80% of global events. Standardized indices (SIs) are routinely used to assess hydroclimate extreme events. However, to what extent such assessment is robust considering the choice of climate epoch (that is, a specific time period with explicit data length) is still not clear especially when developing new SIs. In this study, we use multiple SIs to systematically investigate the sensitivities of global drought and pluvial detection to the length of climate epoch by separating the parameter fitting step from the entire SI calculation process. We find that the sensitivity of event classifications to data length is more similar between Standardized Precipitation Evapotranspiration Index (SPEI) and Standardized Moisture Anomaly Index (SZI) at the six-month time scale, compared to that of Standardized Precipitation Index (SPI). Moreover, despite the symmetric definition of droughts and pluvials, the choice of climate epoch has asymmetric impacts on event detection. Detection of SZI-based droughts is more sensitive to data length than pluvials and generally requires longer series (additional 10 years compared to a 30-year climatology) to accurately fit the tailed distribution, especially over a few hot spot regions, including South Africa, South Asia and Oceania. [ABSTRACT FROM AUTHOR]

(Zr47Cu44Al9)100−xSix (x = 0, 0.5, 1.5 and 2.5 at%) thin-film metallic glasses (TFMGs) were deposited at glass substrate by pulsed laser deposition. The influence of Si content and substrate temperature on the microstructure, optical and electrical properties was investigated. After adding Si in the Zr47Cu44Al9 system, the transmittance of the films enhances obviously, especially in the near-infrared region. The resistivity increases and becomes more sensitive to the temperature due to Si addition. With increasing substrate temperatures from room temperature to 430 °C, (Zr47Cu44Al9)98.5Si1.5 films display fully amorphous structure. Appropriate substrate temperature drastically decreases the resistivity of films without degrading the transmittance. (Zr47Cu44Al9)98.5Si1.5 TFMG deposited at 330 °C exhibits the visible transmittance of 49.38%, the infrared transmittance of 80.27% and the resistivity of 7.62 mΩ cm, which are useful properties for their potential applications in infrared technology with the high requirement of radiation resistance and corrosion resistance. [ABSTRACT FROM AUTHOR]

The Three-North Shelterbelt Project (TNSP) is one of the largest ecological restoration projects of the world. Although its important role in regulating the ecosystem of northern China has been acknowledged, how this project affects the surface water-energy balance deserves further evaluation. This study characterizes spatiotemporal variation of climate variables and vegetation coverage/density over the Three-North Region (TNR) of China using multiple datasets since the implementation of the TNSP. Of particular importance is that effects of vegetation restored during the TNSP on surface water-energy budget are examined for the study domain. Our results show that accompanied by a significant enhancement of vegetation coverage and density in the TNR, its annual air temperature and precipitation have increased 1.46 °C and 89.1 mm, respectively from 1982 to 2015. We find such rise in the air temperature and precipitation plays a positive role in the TNR's vegetation restoration in a sense that the vegetation dynamics show positive correlation with its regional air temperature and precipitation, while more sensitive to precipitation. We also find carbon sequestration of the TNR increases at the cost of greater water consumption through evapotranspiration since the TNSP commences. In some arid regions, revegetation accelerates the water deficit due to an excessive rate of restoring vegetation; yet, no substantial water imbalance occurs as a result of enhanced precipitation and water use efficiency during this period. Although the solar radiation increases with decreases in surface albedo over the last few decades, our results do not reveal an appreciably increasing trend in the land surface temperature of the TNR. This is because the improved vegetation can assimilate CO 2 (mitigating greenhouse gas emissions) and transpire water by photosynthesis, thereby increasing latent heat flux and reducing the warming effect. This study highlights a mixed consequence of the TNSP by inducing both positive and negative effects on the surface water-energy balance over the TNR. [ABSTRACT FROM AUTHOR]

• Positive (negative) correlation between NDVI and drought indices mainly occurs in non-humid (humid) areas. • Water stress is not likely to be the limiting factor for natural vegetation in humid regions, even during droughts. • Natural vegetation exhibits less sensitivity to drought in extreme arid regions. Knowledge of vegetative responses to drought across hydroclimatic zones is crucial for understanding ecohydrologic cycles. Based on monthly self-calibrated Palmer drought severity index (PDSI), standardized precipitation evapotranspiration index (SPEI) at different time scales (1–48 month scales), and normalized difference vegetation index (NDVI), this study examined the relationship between natural vegetation dynamics and drought in the growing season during 1982–2012 at 293 sites over China. Pearson correlations between NDVI and drought indices (PDSI and SPEI) were employed to quantify the association between vegetation and drought. The results show that the Pearson correlations between PDSI and NDVI in growing season (C NP) ranged from −0.47 to 0.84, and the maximum correlation between SPEI and NDVI in growing season (MaxSPEI) ranged from −0.31 to 0.86, within which the negative correlations were mainly observed in the areas dominated by forest in south China. Moreover, the C NP was highly and nonlinearly related to the aridity index (∅) (MaxSPEI showed a similar trend). The relationship between C NP and ∅ indicated that, water stress was not the limiting factor for natural vegetation in humid regions (∅ < 0.98) even during droughts; the drought vulnerability of natural vegetation increased with increasing ∅ up to a point (∅ = 4.68) and then decreased with increasing ∅ when ∅ > 4.68 ; in extreme arid regions, the natural vegetation exhibited less sensitivity to drought. These tendencies could be seen worldwide. The varied physiological properties of plants and the response of photosynthesis to energy processes probably explain some discernible variation. [ABSTRACT FROM AUTHOR]

• Response amplitudes are different for meadow, HCG and MCG, while similar for others. • Rate of wetting event reduced significantly with depth for all land covers except HCG. • Temporal patterns of soil wetting event varied greatly along depths and land covers. • Preferential flow occurred mostly in soils covered by scrubland. • Soil hydraulic properties are key factors in regulating soil wetting events. Understanding the dynamic response of soil moisture to rainfall is critical for hydrological modelling in arid and semi-arid basins. However, little is known about rainfall-related soil moisture dynamics in arid high-altitude mountainous areas due to the absence of long-term high-resolution soil moisture observations. In this study, we investigated the dynamic response processes of profile soil moisture using data from a soil moisture monitoring network in the Qilian Mountains established in 2013 covering altitudes from 2,000–5,000 m a.s.l. To investigate the effects of different land covers on soil moisture response, we selected data from eight soil moisture stations with the same soil textural class and slope, but different land covers (scrubland, meadow, high coverage grassland (HCG), medium coverage grassland (MCG) and barren land). Several indices were evaluated to quantitatively describe soil moisture dynamics during the growing seasons of 2014–2016 based on soil wetting events. In addition, HYDRUS-1D simulations were used to further analyze the effect of land cover on soil moisture dynamics. Our results showed that soil moisture response amplitudes along profile are similar under MCG and barren land, but significantly different under scrubland, meadow and HCG. The rate of soil moisture increment decreased significantly with depth for all land covers, except for the HCG. The temporal pattern of soil moisture increase was highly variable along the soil profiles depending on land cover type. In particular, the difference of response time between the adjacent layers varied from negative values to 280 h with depth. Preferential flow occurred mostly in soils covered by scrubland. Water transferability was higher in deeply rooted soil. Furthermore, sensitivity analysis indicated that soil hydraulic properties are key factors in regulating profile soil wetting events. Our results show that the soil moisture response indices are useful to quantitatively characterize patterns in profile soil moisture dynamics, and provide new insights into the soil moisture profile wetting process (e.g. occurrence of preferential flow etc.), which helps for effective model parameterization and validation, in turn improving hydrological modelling in arid high-altitude mountainous areas. [ABSTRACT FROM AUTHOR]

Highlights • We outline a water-energy balance approach for multi-scalar and multi-category drought analysis. • The proposed approach is able to capture meteorological, hydrological, and agricultural droughts. • The new drought index outperforms previous drought indices (SPEI and scPDSI), especially in non-humid regions. Abstract Different categories of droughts (e.g., meteorological, agricultural, hydrological), and their multi-scalar features often make description of drought onset, persistence, and termination challenging and often subjective. Here we show that a water-energy balance based indicator, named Standardized Moisture Anomaly Index (SZI), better captures multiple categories of droughts and their multi-scalar features. We globally evaluate and compare the performance of SZI with existing drought indicators that use potential evapotranspiration (PET) as a measure of atmospheric water demand including the Standardized Precipitation Evapotranspiration Index (SPEI) and self-calibrated Palmer Drought Severity Index (scPDSI). We show that while PET is a good indicator for characterizing the climate aridity, using it as a measure of atmospheric water demand for drought analysis leads to misrepresentation of droughts, especially over water-limited (non-humid) regions where the actual evapotranspiration is primarily dominated by water availability rather than energy (or PET). The main advantage of SZI is that, instead of PET, it uses a variable termed climatically appropriate precipitation for existing conditions (P ˆ) as the atmospheric water demand metric. Investigating droughts over 32 large basins across the globe, we show that the SZI can better represent meteorological, hydrological, and agricultural droughts compared to SPEI (especially in non-humid basins; 18 out of 32 basins) and scPDSI at multiple time scales. Given that SZI is physically more reasonable in reflecting surface water-energy balance over both humid and non-humid regions, it enables better characterization of different types of droughts in different climatic regions. [ABSTRACT FROM AUTHOR]

• The spatiotemporal continuity of droughts was explored using a three-dimensional clustering algorithm. • Droughts can migrate hundreds of kilometers from the source sites in the agro-pastoral ecotone of northern China. • The more severe and longer duration of meteorological drought, the more likely it is to trigger agricultural drought. Understanding the spatiotemporal evolution of droughts is critical for food security and water allocation. In this study, we propose an approach to construct the linkage of the propagation from meteorological drought to agricultural drought to explore the simultaneous spatiotemporal evolution of droughts based on a 3-dimensional clustering algorithm. We first evaluate the improvement of the downscaled high-resolution outputs from the Weather Research and Forecasting (WRF) model to reanalysis data in detecting wet-dry variations in the agro-pastoral ecotone of northern China (APENC). The WRF simulation results well characterize the evolution of droughts with a high correlation coefficient of 0.82 (p <0.05), which implies that the WRF downscaling model provides reliable hydrometeorological results for assessing and analyzing long-term wet-dry variations. Subsequently, we identify and track the spatiotemporal evolution of each individual drought event in the APENC for the first time. Based on the standardized precipitation index calculated from the WRF outputs, a total of 185 drought clusters were identified during 2000–2017, with 28 drought events lasting at least 3 months duration occurring in the APENC. The characteristics of the different drought events vary considerably. Droughts in the APENC have a larger percentage of propagation to the northeast and northwest and migrated hundreds of kilometers from the source sites. The results of the propagation of meteorological droughts to agricultural droughts indicate that 53.75% of the meteorological drought events progressed further to agricultural droughts. Agricultural droughts exhibit spatial variations consistent with meteorological droughts. Agricultural droughts have 1.69 months onset lag time, 2.12 months termination lag time, and overall longer duration than meteorological droughts in the APENC. Our findings provide valuable information for the mechanism and prediction of drought propagation. [ABSTRACT FROM AUTHOR]

• A method is developed to estimate maximum vegetation coverage supported by rainwater. • Leaf area index under the maximum scenario is 11.5% higher than actual scenario. • Under the maximum scenario vegetation could absorb 25% more carbon. • The ecosystem water use efficiency under the maximum scenario is 17.9% higher. • Sustainability of vegetation restoration can be enhanced by efficient use of rainwater. Large-scale anthropogenic revegetation brings new challenges by enhancing water consumptions in non-humid regions, even if it improves ecosystems. Water resources in water-stressed areas are primarily provided by precipitation, and excessive afforestation can potentially lead to severe imbalance between water supply and demand due to limited rainwater resources. Therefore, it is essential to evaluate the maximum vegetation coverage and productivity capacity supported by rainwater resources. In this study, the sustainability of revegetation was characterized by calculating the upper limit of vegetation leaf area index (LAI) supported by rainwater resources. The carbon sequestration capacity and efficiency of the maximum and the actual vegetation scenario were compared over the Loess Plateau (LP), which is well known as a region experiencing both large-scale vegetation restoration and severe water shortages. The upper limit on LAI was calculated based on evapotranspiration (ET) supported by rainwater resources, using the Shuttleworth-Wallace (S-W) model optimized in this study by adding dynamic vegetation and carbon dioxide components. The carbon sequestration capacity and efficiency of vegetation under different restoration scenarios were estimated in an analytical water use efficiency (WUE) model. Both the models perform well and are consistent with observations. The results show that the LAI of the maximum vegetation scenario is 11.5% higher than the actual scenario if vegetation on the LP is restored to its maximum level. The average gross primary productivity under the maximum vegetation scenario is 25.0% higher than the actual scenario, while the ecosystem WUE will increase by 17.9%. It should be noticed that the maximum scenario is a theoretical upper limit based on ideal assumptions. Our findings reveal that improving rainwater utilization efficiency can further develop the potential of sustainable vegetation restoration while improve its efficiency, and will provide guidance and theoretical support for vegetation restoration planning on water-scarce regions. [ABSTRACT FROM AUTHOR]

• Meadow tends to retain infiltration at the surface soil due to mattic epipedon. • Hillslope sites affect infiltration partitioning by influencing soil properties. • The quantitative indices improve our understanding of infiltration partitioning. Infiltration process controls how rainfall is stored in soil and subsequently used by plants, thus, plays a critical role in eco-hydrological processes. However, the vertical pattern of infiltration partitioning within a soil profile and the factors that control it remain poorly understood, especially in data-scarce mountainous areas. Based on a large-scale long-term soil moisture (SM) network in the Qilian Mountains, Northwest China, we explored infiltration partitioning and its control factors using a new metric, percentage of soil water storage increment in each layer to the soil profile during a rainfall infiltration event (PSTI). We found that both vegetations with deep roots and wet SM conditions facilitated infiltration into the deeper soil, although meadow favored infiltration within the surface layer. Hillslope stations showed a higher degree of infiltration partitioning in subsurface layers than the flatland stations due to the influence of topography on soil properties. Meanwhile, the increasing slope gradient will reduce the partition of infiltration at the subsurface layers. Among the soil properties, sand content, soil organic carbon, α (parameter of soil retention curve), and soil saturated hydraulic conductivity promoted infiltration into greater depth, while clay content and bulk density had the opposite effect. The major factors controlling the pattern of infiltration partitioning were n (parameter of soil retention curve) for 0–10 cm depth, α for 10–20 cm and 20–30 cm depths, and SM for PSTI below 30 cm. This quantitative analysis method for the infiltration partitioning improves our understanding of infiltration regimes, and supports water resources management in dryland mountains. [ABSTRACT FROM AUTHOR]

In many practical applications like autonomous driving and robot navigation, the large-scale 3D point cloud segmentation method is required to be both fast and efficient. In this paper, a fast and efficient large-scale point cloud semantic segmentation network, namely FFA-Net, is proposed. We used U-Net architecture as the backbone architecture, and used the random sampling algorithm to down sample the 3D points faster. To maintain the speed advantage of random sampling and protect integral information of 3D point cloud, we designed a lightweight operator, called fast feature aggregation (FFA) operator, to learn local features of 3D point cloud efficiently, and we equipped this FFA operator in a dilated residual block to aggregate local features within a larger receptive field hierarchically. This operator contains only minimal of learnable parameters, which makes the segmentation network not only improved in segmentation performance, but also in computation speed. Extensive experimental results on three large-scale 3D point cloud benchmarks have verified the effectiveness of our method in both segmentation performances and speed. [ABSTRACT FROM AUTHOR]

Reliable drought monitoring and analysis requires appropriate water demand estimates, particularly in arid and semiarid regions. Although potential evapotranspiration ( PET ) is commonly used to estimate water demand when monitoring droughts, the PET only considers the maximum atmospheric demand for water and ignores other variables that can affect surface water consumption and thus drought conditions. As such, the concept of climatically appropriate precipitation for existing conditions ( P ˆ ), which considers soil moisture loss and recharge, runoff, and evapotranspiration, is developed as a modified water demand estimate in drought modeling. This study compared and evaluated the performance of PET and P ˆ as water demand estimates in drought monitoring over arid and semiarid regions. The results show that the magnitudes of PET are much higher than precipitation ( P ) in the study region, particularly for the area with annual average P less than 300 mm, indicating that PET as a water demand indicator would lead to water demand being given too much weight in drought quantification. Accordingly, using the differences between P and PET to characterize surface water deficit/surplus could result in a water imbalance and inaccurate drought quantification in water-limited regions. In the physical world, water demand and supply are generally balanced over the long term, which is reasonably reflected by the differences between P and P ˆ . The magnitudes and patterns of P and P ˆ were generally similar to each other over the long term, meaning P ˆ as water demand is physically more reasonable and reliable than PET in monitoring droughts. Moreover, the drought identification results based on the P ˆ are more consistent with changes in observed streamflow and CPC soil moisture than the PET . These demonstrated that the P ˆ as a modified water demand metric provides improved information for drought modeling in arid and semiarid regions. [ABSTRACT FROM AUTHOR]

In this study, the coupling effects of climate aridity and vegetation restoration on runoff and sediment yield over the Loess Plateau were examined and characterized. To take into consideration the complexity of drought, as well as the varied strengths and weaknesses of different drought measures, two drought indices are selected to identify and evaluate drought variability. The Normalized Difference Vegetation Index (NDVI) data were obtained to monitor and express spatiotemporal variations in vegetation cover. The results show that most regions of the Loess Plateau experienced increasingly severe droughts over the past 40 years, and these regions comprise the major source of the Yellow River sediment. Climatic drying initially occurred in the 1990s, and became statistically significant in 2000s. The increasingly severe droughts could negatively impact surface and groundwater supplies as well as soil water storage, but may also minimize surface runoff yield, which is one of the major causes of soil erosion on the Loess Plateau. Vegetation cover on the Loess Plateau was significantly improved after the implementation of “Grain for Green” project, which were helpful for controlling severe soil erosion. With the impacts of the construction of check dams, terraces and large reservoirs, runoff and sediment yield over the Loess Plateau initially exhibited downward trends between 1970 and 1990. After 1990, with the effects of the climate warming and drying, a second sharp reduction in runoff and sediment yield occurred. The coupling effects of climate aridity and vegetation restoration have led to a third significant decrease in runoff and sediment yield over the Loess Plateau after 2000. [ABSTRACT FROM AUTHOR]

Styrene–maleic anhydride copolymer (SMA) was used as a compatibilizer to improve the interfacial interaction between graphene sheets and polystyrene matrix. SMA mediated graphene sheets are closely encapsulated by a polymer layer and uniformly dispersed compared to the graphene sheets without SMA. The presence of SMA not only improves the melt modulus and its frequency-independence, but also results in an earlier transition from liquid-like to solid-like, indicating the formation of a percolated conducting network at a low content of graphene with the assistance of SMA. Accordingly, the different frequency dependences of electrical conductivity also lead to a much lower threshold of 0.17 vol.% for SMA modified nanocomposites compared to 0.52 vol.% for the unmodified counterparts, further confirming the earlier formation of a graphene network in the matrix. The improved rheological and electrical properties of the polystyrene nanocomposites are attributed to the homogeneous dispersion of the graphene sheets and the enhanced interfacial interaction between the graphene sheets and the polystyrene matrix. [ABSTRACT FROM AUTHOR]

Abstract: Pt-loaded WO3 thin films were deposited on oxidized Si substrates under various discharge gas pressures at room temperature using reactive magnetron sputtering. Structural characterizations by means of X-ray diffraction and field emission scanning electron microscopy show that the films composed of nano-size grains have a monoclinic structure. The films become more porous as the discharge gas pressure increases due to the decrease in film density and the increase in effective surface area. Gas sensing properties demonstrate that the films show reversible response to H2S with various concentrations. Under the same operating conditions the sensor response increases and the operating temperature at which the maximum response is shown decreases with discharge gas pressure. The highest response of 3512 is obtained for a Pt-loaded porous film deposited at 12Pa upon exposure to 5ppm H2S at an operating temperature of 100°C. Such a high response of a Pt-loaded porous film at a low operating temperature is discussed in relation to the Schottky-barrier-limited transport as well as the chemical mechanism of Pt loading. [Copyright &y& Elsevier]

Drought is a complex natural hazard that is poorly understood and difficult to assess. This paper describes a VIC-PDSI model approach to understanding drought in which the Variable Infiltration Capacity (VIC) Model was combined with the Palmer Drought Severity Index (PDSI). Simulated results obtained using the VIC model were used to replace the output of the more conventional two-layer bucket-type model for hydrological accounting, and a two-class-based procedure for calibrating the characteristic climate coefficient ( K) was introduced to allow for a more reliable computation of the PDSI. The VIC-PDSI model was used in conjunction with GIS technology to create a new drought assessment index (DAI) that provides a comprehensive overview of drought duration, intensity, frequency, and spatial extent. This new index was applied to drought hazard assessment across six subregions of the whole Loess Plateau. The results show that the DAI over the whole Loess Plateau ranged between 11 and 26 (the greater value of the DAI means the more severe of the drought hazard level). The drought hazards in the upper reaches of Yellow River were more severe than that in the middle reaches. The drought prone regions over the study area were mainly concentrated in Inner Mongolian small rivers, Zuli and Qingshui Rivers basin, while the drought hazards in the drainage area between Hekouzhen-Longmen and Weihe River basin were relatively mild during 1971-2010. The most serious drought vulnerabilities were associated with the area around Lanzhou, Zhongning, and Yinchuan, where the development of water-saving irrigation is the most direct and effective way to defend against and reduce losses from drought. For the relatively humid regions, it will be necessary to establish the rainwater harvesting systems, which could help to relieve the risk of water shortage and guarantee regional food security. Due to the DAI considers the multiple characteristic of drought duration, intensity, frequency, and spatial extent, and because it is based on the VIC-PDSI model and GIS technologies, the DAI could provide some new way on directly comparing the drought hazards over different regions during a long-term period. The result of this study may be useful to decision makers when formulating drought management policies to alleviate the risk of water shortages and guarantee regional food security. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we analyzed the drought variation trends in six subregions of the Loess Plateau over the past four decades. To do this, we used a new method wherein we combined the Variable Infiltration Capacity (VIC) Model for simulating watershed hydrological processes and Palmer Drought Severity Index (PDSI) for drought assessment and analysis. A new classified calibration procedure of climate characteristic coefficient, K j , was introduced in the study to improve the traditional PDSI computation method. The results suggest that the total area affected by drought in subregions 1–3 located in the middle reaches of the Yellow River mainly exhibited downward trends during 1971–2010. As these domains are the principal sediment sources of the Yellow River, the decreasing trends in drought area could benefit to vegetation recover in these regions, which are key sites of “Grain for Green” project, and help to control the severe soil and water losses. However, subregions 4–6 located in the upper reaches of the Yellow River primarily experienced upward trends in the total drought area. These subregions are the main grain producing areas of the study region, and the increase in drought area may cause damage to agricultural production and regional food security. The spatial distribution of drought frequency increased from southeast to northwest on the Loess Plateau. Most areas of the subregions 4–6 of the plateau exhibited an upward trend in drought frequency as indicated by a Mann–Kendall test, and the upward trend will show persistent behavior in the future, according to a Hurst exponent analysis. Generally speaking, the drought hazard in the upper reaches of the Yellow River tended to be increasingly severe, while drought hazard in the middle reaches has relieved to certain extent over the past four decades. [Copyright &y& Elsevier]

Abstract: Rich husk (RH) is a naturally occurring inorganic/organic composite consisting mainly of lignocelluloses and silica. Due to the high silica content in RH, their addition into synthetic polymers may play certain synergistic roles in the flammability of the resulted composites. In this study, the thermal stability and flammability of RH-filled HDPE (HDPE/RH) ecocomposites with different compositions have been evaluated by thermogravimetric analysis and cone calorimetry, respectively. It is observed that the addition of RH has effectively delayed the thermo-oxidation process of the HDPE matrix by about 40°C, and evident flame retardant effect has also been observed (in comparison to the results obtained from neat HDPE). From analysis carried out on the composition and structure of the combusted residues, it can be inferred that the main mechanisms for the flame retardancy in the HDPE/RH ecocomposite are due to the heat shielding and diffusion barrier effects of the silica-based protective layer which was formed during the heating process. [Copyright &y& Elsevier]

Abstract: The effect of Si addition on the glass-forming ability (GFA) of (Zr47Cu44Al9)100−x Si x (x =0, 0.5, 1, 1.5, and 2.5) metallic glass alloys was investigated by using X-ray diffraction (XRD), optical microscopy, and differential scanning calorimetry (DSC). The maximum diameter of glassy rods increased from 4mm for the Zr47Cu44Al9 alloy to 6mm for the (Zr47Cu44Al9)98.5Si1.5 alloy without detectable crystallinity when prepared using copper mould casting. Different criteria are used to evaluate the influence of Si content on the GFA. Due to the suppression of the formation of the primary CuZr phase and the induction of the composition close to the eutectic point, properly adding Si can enhance the GFA of the (Zr47Cu44Al9)100−x Si x alloy. The possible mechanisms involved in the achievement of this GFA are also discussed. [Copyright &y& Elsevier]

Abstract: The influence of well-dispersed nano-clay filler on the morphology of thermotropic liquid crystalline polymer (TLCP) in nylon-6 matrix was investigated by melt extrusion process. The good dispersion of clay in the hybrid blends was confirmed by X-ray diffraction, transmission electron microscopy and rheological measurement. Morphological observation showed that the clay platelets had dramatic influences on the dispersion and deformation of TLCP phase. The TLCP droplets got smaller at the clay content ≤3wt%, and deformed into fibrils at the clay content up to 5 and 7wt%. The morphology evolution of TLCP in the hybrid blends, especially at 7wt% of clay loading, was consistent well with the prediction based on the micro-rheology parameters such as the viscosity ratio of the dispersed phase to the matrix (η d /η m) and the ratio of capillary number to the critical capillary number (Ca/Cacrit). This enhanced fibrillation of TLCP droplets was attributed to the role of nano-clay particles as a compatibilizer to improve the interfacial adhesion and to suppress the interfacial slip between TLCP and nylon phases in the melt, so that the shear stress was effectively transferred to the dispersed TLCP phase. [Copyright &y& Elsevier]

The sintering and compositional dependencies of dielectric properties in PMW–PT–PNN ceramics have been investigated. The present work confirms that sintering temperature had a large influence on the dielectric properties in this ternary system. It was found that the main causes for the flat temperature dependence are due to shifting and broadening of the dielectric anomaly. [Copyright &y& Elsevier]

Assesses major issues concerning the problems in China's educational system. Implication of reform and development for educational development; Relationship between education and economy; Problems affecting moral and intellectual education; Issues on fiscal educational funds; Principal functions of education.

Background: In this study, we present the unique case of a patient with knee osteoarthritis (OA) of the medial compartment and posterior cruciate ligament (PCL) deficiency who underwent simultaneous medial unicompartmental knee arthroplasty (UKA) and PCL reconstruction. Case presentation: A 49-year-old male patient presented with a 1-year history of pain and instability in the left knee. The patient had previously experienced a trauma-related injury to the PCL of the left knee that was left untreated. Imaging and physical examination confirmed the presence of left medial knee OA along with PCL rupture. To address these issues, the patient underwent UKA combined with PCL reconstruction. The patient's Lysholm score was 47 before surgery and 81 three months after surgery, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score was 29 before surgery and 18 three months after surgery, and the International Knee Documentation Committee (IKDC) subjective score was 56.3 before surgery and 74.7 three months after surgery. Six months after surgery, the patient's gait returned to normal, and he was able to jog. Conclusion: This case report presents the first instance of UKA combined with PCL reconstruction and introduces a novel treatment approach for patients suffering from medial knee OA and ligament injury. [ABSTRACT FROM AUTHOR]

Objectives: Despite the use of multimodal analgesia, patients undergoing knee arthroplasty still encounter residual moderate pain. The addition of betamethasone to local anesthetic has been shown to improve postoperative pain. However, it remains uncertain whether the positive effects of perineural or intravenous administration of betamethasone on analgesia outcomes lead to better early mobility and postoperative recovery. Methods: Between June 2022 and February 2023, a total of 159 patients who were undergoing knee arthroplasty were included in this study. These patients were allocated randomly into three groups: (i) the NS group, received ropivacaine 0.375% and intravenous 3mL 0.9% normal saline; (ii) the PNB group, received ropivacaine 0.375% plus perineural betamethasone (12mg) 3mL and intravenous 3mL 0.9% normal saline; and (iii) the IVB group, received ropivacaine 0.375% and intravenous betamethasone (12mg) 3mL. Results: Both perineural and intravenous administration of betamethasone led to improved median (IQR) numeric rating scale (NRS) scores on the 6‐meter walk test, with a score of 1.0 (1.0–2.0) for both groups, compared with 2.0 (1.0–2.0) for the NS group (p = 0.003). Compared to the NS group, both the PNB and IVB groups showed significant reductions in NRS scores at 24 and 36 h after surgery, along with a significant increase in ROM at 24, 36, and 48 h post‐operation. Additionally, it exhibited lower levels of cytokine IL‐1β and TNF‐α in fluid samples, as well as lower level of HS‐CRP in blood samples in the PNB and IVB groups compared to the NS group. Conclusion: The administration of perineural and intravenous betamethasone demonstrated an enhanced analgesic effect following knee arthroplasty. Furthermore, it was associated with reduced levels of IL‐1β, TNF‐α, and HS‐CRP, as well as enhanced knee ROM, which is conducive to early ambulation and postoperative rehabilitation after knee arthroplasty. [ABSTRACT FROM AUTHOR]

Microspherical ZnO composites were prepared by introducing carbon dots (CDs) in situ by a one-step hydrothermal method. The effects of precursor and calcination treatments on the microstructure and morphology, compositional features and triethylamine (TEA) detection were carefully investigated. The results show that the addition of excess urea promotes the formation of CDs, the produced UC-ZnO composite presents microspheres with relatively smooth surface after calcination, and the retained CDs form heterojunctions with ZnO. TC-ZnO composite produced by adding excess trisodium citrate displays bowl-shaped depressions on the surface. After calcination, the porous structures with large specific surface area and carbon incorporation are achieved. The two composites show improved gas-sensitive response and reduced detection limit for TEA. The sensitivity for 100 ppm TEA at the optimal operating temperature of 350°C is 357 for UC-ZnO and 526 for TC-ZnO sensor, which are 21% and 80% higher than that of pure ZnO, respectively. The TC-ZnO sensor possesses an excellent low detection limit of 32 ppb. The introduction of CDs effectively modulates the morphology and interface state of ZnO microspheres, and improves the gas-sensitive performance. [ABSTRACT FROM AUTHOR]

• We evaluate multiple ET data models including NLDAS-2 and experimental NLDAS-Testbed. • The NLDAS-Testbed ensemble mean has a slightly lower uncertainty than that of NLDAS-2. • The comparison suggests some weaknesses and strengths in NLDAS-Testbed. • The findings help further improvement of these models and support NLDAS development. Terrestrial evapotranspiration (ET) is a major component of the surface hydrological cycle and controls land-atmosphere feedbacks by modulating the surface energy budget. Accurate ET quantification at global or regional scales is crucial for understanding variations in carbon and water cycling in a changing environment. Although various grid-based ET data models have been developed using multiple approaches, these vary in concept and physical scheme, leading to differences in performance. We examine uncertainties associated with the limitations of the physics used to assist in model selection and improvement. We evaluate multiple ET data models, including estimates derived from a variety of land surface models (LSMs) based on the operational North American Land Data Assimilation System (NLDAS) phase 2 (NLDAS-2) and the experimental NASA LIS-based NLDAS Testbed (NLDAS-Testbed) drivers, and satellite retrievals, compared to water budget-derived ET and tower observations. Overall, all models are able to capture the spatial variability of mean annual water balance-based ET (ET wb) and monthly seasonal cycles of tower ET measurements, although there is a large range of estimates. NOAH28, FLUXNET, SSEBop, LandFlux, and GLEAM perform best, as demonstrated by their higher correlation and smaller bias and RMSE values. Simple relative uncertainty analysis shows that the NLDAS-Testbed ensemble mean has a slightly lower uncertainty than that of the NLDAS-2 ensemble. Our study indicates that NLDAS-Testbed/VIC412 (NLDAS version/LSM version) is improving and NLDAS-Testbed /CLSM is deteriorating relative to NLDAS-2/VIC403 and NLDAS-2/Mosaic. NLDAS-Testbed /NOAH36 and NLDAS-Testbed /NOAHMP36 are comparable to NLDAS-2/NOAH28, although biases between models and ET wb exhibit opposite trends. These findings will help further improvement of these models and support future NLDAS development. [ABSTRACT FROM AUTHOR]

• Grassland expansion in the APENWC reduces mean annual land surface temperature. • Grassland transpiration increases ET in summer, but decreases it in other seasons. • The water vapor in the west and south are the important moisture contributors to precipitation in the region. • The APENWC contributed additional moisture from local ET into the north of the region. • Increasing ET and declining precipitation lead to soil drying and raise probabilities of summer drought in the region. A better understanding of responses of the regional water-energy cycle to land use/cover change (LUCC) is important for ecological restoration in the agro-pastoral ecotone, Northwest China (APENWC). In this study, we examined the responses to various types of LUCC in the APENWC during the implementation of the Grain-for-Green project between 1993 and 2010 using the weather research and forecasting (WRF) model. The performance of the WRF model was validated by multiple types of observations. Results show that the WRF can accurately simulate regional water and energy processes in the APENWC, and that the water-energy cycles in the region are strongly affected by vegetation dynamics. During the period of 1993 and 2010, the most obviously increased land cover types were the grassland and barren land, and the decreased land cover types were shrublands and croplands in the study region. A significantly negative correlation (R2 = 0.78) between land surface temperature (LST) and albedo was found, associated with a 0.5 °C reduction in the annual mean surface temperature in the APENWC between 1993 and 2010. Negative correlations between changes in evapotranspiration (ET) and albedo during the period in all seasons were also detected, except summer, when the correlation was positive (R2 = 0.49). This is attributed to transpiration from plants being the main contributor to ET in summer and, hence total ET. The changes resulted in an increase of ET by 19.79 mm in summer, and decreases of ET by 1.15 mm, 13.22 mm, and 0.96 mm, respectively, in spring, fall, and winter. The LUCC also resulted in reductions in precipitation (of 2.3, 7.31, and 7.8 mm in spring, summer, and fall, respectively) by altering local ET and vapor flux cycles in the APENWC, and the study region contributed additional moisture from the local ET into the north of the region. The findings show that the grassland expansion reduces mean land surface temperature, which will delay germination of seeds and initiation of vegetation growth in spring. Increases in seasonal ET and reductions in seasonal precipitation will lead to soil drying, exacerbating risks of summer drought in the APENWC. The findings provide important information in facilitating formulation of effective strategies for sustainable development and ecological restoration in the APENWC and similar regions. [ABSTRACT FROM AUTHOR]

Vegetation is the major component of the terrestrial ecosystem. Understanding both climate change and anthropogenically induced vegetation variation is essential for ecosystem management. In this study, we used an ensemble empirical mode decomposition (EEMD) method and a linear regression model to investigate spatiotemporal variations in the normalized difference vegetation index (NDVI) over the agropastoral ecotone of northern China (APENC) during the 1982–2015 period. A quantitative approach was proposed based on the residual trend (RESTREND) method to distinguish the effects of climatic (i.e., temperature (TEM), precipitation (PRE), total downward solar radiation (RAD), and near surface wind speed (SWS)) and anthropogenic effects on vegetation variations. The results showed that the NDVI exhibited a significant greening trend of 0.002 year−1 over the entire study period of 1982–2015 and that areas with monotonous greening dominated the entire APENC, occupying 40.97% of the region. A browning trend was also found in the central and northern parts of the APENC. PRE presented the highest spatial correlation with the NDVI and climate factors, suggesting that PRE was the most important factor affecting NDVI changes in the study area. In addition, the RESTREND results indicated that anthropogenic contributions dominated the vegetation variations in the APENC. Therefore, reusing farmland for grass and tree planting made a positive contribution to vegetation restoration, while deforestation, overgrazing, and the reclamation of grasslands were the opposite. In addition, with the continuous implementation of national ecological engineering programs such as the Grain to Green Program, positive human activity contributions to vegetation greening significantly increased. These results will support decision- and policy-making in the assessment and rehabilitation of ecosystems in the study region. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to investigate the correlation between lower limb alignment and patient outcomes after lateral unicompartmental knee arthroplasty (LUKA). Methods: In this retrospective study, the information of 51 patients who underwent lateral UKA was collected after an average of 27months of follow-up (13 to 60 months). Evaluation indicators include the AKS and WOMAC score. The Kellgren-Lawrence grade is used to evaluate the severity of osteoarthritis, while the hip-knee-ankle (HKA) angle is utilized to measure the valgus angle of lower limb alignment. Result: Patients with postoperative valgus (≥ 3°) alignment had the best outcomes, while those with varus (≤-3°) alignment had the worst outcomes (p < 0.001). Furthermore, it was noted that patients with preoperative mild valgus (≤ 4°) alignment had worse postoperative outcomes than those with severe valgus (≥ 7°) alignment (p < 0.05). The study also revealed a positive correlation between postoperative valgus and WOMAC scores (p < 0.001), whereas a negative correlation was observed between the change in valgus angle and WOMAC scores (p = 0.005). Conclusion: During follow-ups, we found that lower limb alignment seems to be an independent predictor of postoperative outcomes. It is recommended that more than 3° of valgus alignment should be maintained after LUKA. Surgeons performing lateral UKA should be cautious of overcorrecting alignment, particularly in patients with preoperative mild valgus alignment. [ABSTRACT FROM AUTHOR]

Recently, the success of Transformer in natural language processing and image processing inspires researchers to apply Transformer in point cloud processing. However, existing point cloud Transformer methods have problems with massive parameters, heavy computation, and lack of local features due to the use of global self-attention. To solve these problems, this paper presents a novel point-voxel dual stream Transformer (PVDST) network, which combines the voxel-based convolution and point-based local attention, extracting the local and contextual features of point clouds simultaneously. To reduce the parameters and computation of self-attention and make the contextual features contain more position information, we design the local-aware attention module with explicit position encoding and neighbor embedding, which conducts the attention calculation locally. Based on our local-aware attention module and the cross-attention mechanism, we design a unique way to adaptively fuse the local and contextual features. Extensive experiments on shape classification, object part segmentation, and semantic segmentation tasks demonstrate that PVDST achieves competitive performance compared with other methods. [ABSTRACT FROM AUTHOR]

Periodic metal lines are the first kind of metamaterials, which typically exhibit plasmonic resonances to the normally incident waves polarized perpendicularly to them, i.e., transverse magnetic (TM) waves. Meandered lines can obtain resonances for both TM and transverse electric (TE) incidences and have found important applications in chirality and polarization conversion. Recently, several stimuli have been investigated to dynamically modulate the optical properties of periodic lines, which simultaneously tune both TE and TM resonances and show little polarization dependence. In this work, metal-graphene hybrid meandered-line metamaterials are designed for polarization-selective modulation at terahertz frequencies for the first time. The periodic lines meandered in S-shape resonate at 103 GHz for TE waves and at 195 and 320 GHz for TM waves, respectively. Graphene strips are patterned in pairs right at the bending corners along the polarization direction of TE waves, which produce even plasmonic dipole mode for TE incidence. In contrast, they are asymmetric with respect to the TM waves and generate odd coupling mode under TM incidence. These modes with various field concentrations exhibit considerable modulation difference to the graphene conductivity variation. As the graphene chemical potential sweeps, TE transmittance is modulated from 0.7 to 0.47 at 100 GHz, and TM transmittance is modulated just from 0.4 to 0.39 at 190 GHz and from 0.57 to 0.52 at 289 GHz, respectively. The corresponding modulation axial ratio is as large as 23 and 4.6 under a low bias from -1.2 to 1.2 V. This work paves a new way to control terahertz waves polarization-selectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Previous observational researches have discovered a connection between circulating concentrations of micronutrients and attention deficit hyperactivity disorder (ADHD). However, the results may be influenced by confounding factors and reverse causation. This study aims to explore the causal relationship between circulating concentrations of micronutrients and ADHD using Mendelian randomization (MR). In a two-sample MR context, we used summary data from the major European genome-wide association studies (GWAS) for these illnesses to assess the genetically anticipated effects of circulating concentrations of micronutrients on ADHD risk. In order to achieve this, we took single nucleotide polymorphisms (SNPs) from the GWAS that were highly related with concentrations of nine micronutrients. The corresponding data for ADHD were extracted from the Psychiatric Genomics Consortium. Inverse-variance weighted (IVW) method was used as the main MR analysis, and the reliability of the study's conclusions was assessed using sensitivity analyses. Our MR analyses showed that the copper level may be associated with a reduced risk of ADHD. However, the significance of the research results is weak. There were no clear relationships between other micronutrients and ADHD. Our sensitivity studies confirmed the findings of the primary IVW MR analyses. According to this study, there may be some association between copper level and ADHD, but the significance of the research results is weak, and it is recommended that copper level should be used as a long-term monitoring indicator for further research. The results provide a new idea for the further study of ADHD, and provide guidance for the prevention and treatment of ADHD. [ABSTRACT FROM AUTHOR]

• Afforestation boosts the atmospheric water cycle by increasing water vapor and precipitation. • Afforestation enhances evapotranspiration and precipitation recycling. • Afforestation causes an abnormal cyclone, thereby leading to increased moisture advection. • An intensified external atmospheric water cycle dominates the raised precipitation. • Afforestation causes more water vapor to be received by downwind areas. Afforestation is an efficient measure to mitigating climate change and achieving carbon neutrality. However, there is a growing concern regarding the impact of afforestation on water resource availability owing to the water consumption through evapotranspiration (ET). The Loess Plateau (LP) in China has implemented the largest afforestation program in the world, the Grain for Green Program (GFGP), to curtail severe soil erosion. However, the effects of large-scale afforestation on the atmospheric branch of the hydrological cycle (i.e., the atmospheric water cycle (AWC)) are poorly understood. Combining a regional climate model and an analytical precipitation recycling model, this study quantitatively investigated the responses of precipitation recycling and components of the atmospheric water cycle to the GFGP over the LP during the rainy season. Two long-term simulations with high resolution were conducted for the LP's regional climate under two scenarios: with and without the implementation of the GFGP. Results show that the GFGP intensified the AWC and increased the precipitation and atmospheric water vapor. The GFGP enhanced the ET and precipitation recycling ratio of the internal branch of the AWC, which contributed 15.51% of the increased precipitation. Meanwhile, the contribution of the external branch was 84.49%. In addition, both the inflow and outflow moisture fluxes showed increases induced by the GFGP; the inflow was larger than the outflow, leading to more moisture being retained on the LP. Moreover, the enhanced ET reinforced surface diabatic heating and caused an abnormal cyclone, resulting in more moisture being advected from the southern boundary, which can partly counteract the weakening East Asian summer monsoon. Furthermore, the GFGP has remotely strengthened the water vapor advection being received by downwind areas. This work advances the current understanding of the way large-scale afforestation affects the hydrological cycle from the viewpoint of the AWC, and can help direct future afforestation plans towards science-informed carbon neutrality and sustainable ecosystem management. [ABSTRACT FROM AUTHOR]

Objective: Bone cement releases a large amount of heat as it polymerizes. Skin burns caused by discarded bone cement are not well understood during arthroplasty. It is important to study the correlates and mechanisms of scalding and to accurately evaluate the severity of burns to guide treatment decisions. Methods: Standardized burns were created in eight anesthetized rabbits using different thicknesses of bone cement. Bone cement was uniformly stirred to make thicknesses of 1 mm, 4 mm, 8 mm, 12 mm, 16 mm, and 20 mm and a 20 × 40 mm cuboid. Bone cement samples were then placed on the back of a rabbit, and the temperature changes were recorded with an industrial digital thermometer. One hour later, the appearance of scalded skin was observed, and the rabbits were euthanized. The scalded parts were cut to make pathological sections and stained with HE, and the differences in the depth of the scalded skin caused by different thicknesses of bone cement were observed under a light microscope. Results: Damage caused by 1 mm‐, 4 mm‐, 8 mm‐, 12 mm‐, 16 mm‐, and 20 mm‐thick bone cement samples mainly involved the epidermis, the papillary dermis, the reticular dermis layer, and the full thickness of the skin and the subcutaneous tissue. The maximum temperature of 1 mm, 4 mm, 8 mm, and 12 mm bone cementation had a statistically significant difference (p < 0.001), while there was no significant difference between 12 mm, 16 mm, and 20 mm samples (p = 0.856). The time to severe scalding with bone cement at temperatures above 70°C was significantly different between different thicknesses (p < 0.001). Conclusion: The heat released by different thicknesses of bone cement leads to different maximum temperatures and the duration of severe burns, resulting in different degrees of skin burns. Attention should be paid to discarded bone cement to prevent this potential complication in knee arthroplasty. [ABSTRACT FROM AUTHOR]

Hafnium oxide (HfO2) multilayer films were prepared on a glass substrate by pulsed laser deposition, and a novel middle metal layer of Cu40Ag60 was developed. The influence of CuAg thickness and substrate temperature on structural, optical, electrical and morphological characteristics of HfO2/CuAg/HfO2 films were carefully investigated. Multilayer films with different CuAg thickness deposited at room temperature exhibit amorphous structures. As the CuAg thickness varies from 4 to 24 nm, the visible transmittance is kept between 63 and 80%, while the near-infrared transmittance and sheet resistance undergo significant reduction. Increasing the substrate temperature from 100 ℃ to 350 ℃ induces the transformation of HfO2 from amorphous to the crystalline structure, while the near-infrared transmittance and sheet resistance gradually increase. HfO2(50 nm)/CuAg(16 nm)/HfO2(50 nm) multilayer film grown at 150 ℃ exhibits optimal optical and electrical properties with the transmittance of 78.2% in the visible region, 17.7% in the near-infrared region, sheet resistance of 8.59 Ω/◻ and the highest figure of merit of 1.09 × 10–2 Ω−1, which are useful for their potential application in the field of heat mirror and optoelectronics. Furthermore, the possible mechanisms involved in obtaining low infrared transmittance and reduced sheet resistance were explored. [ABSTRACT FROM AUTHOR]

The thermal imidization process of 1,2,4,5-benzenetetracaboxylic (PMDA)/4,4’-diamnodiphenyl ether (4,4′-ODA) solutions in N -methyl-2-pyrrolidone (NMP) from polyimide (PI) precursor, poly (amic acid) (PAA), was systematically investigated through a series of characterization methods, such as Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). At the low-temperature drying stage, mechanical properties and T g of polymer films were increased as a result of solvent removal. TGA method was used to quantitatively monitor the evaporations of hydrogen-bonded solvents on PAA and of the dehydration during the imidization reaction that occurred above 150 °C. During the imidization stage, the interplay between the solvent evaporation and the imidization was the key factor that determined the enhancement of the mechanical properties and T g . The degree of imidization approached 94% when the temperature was increased to 250 °C. A “complete” imidization was achieved by annealing between 350 and 400 °C. The enhancement in the mechanical properties of final PI films may result from the increased T g and the crystallized structure formed during the annealing stage. [ABSTRACT FROM AUTHOR]

Water shortage is a chronic problem in arid Northwest China, where agriculture cannot exist without irrigation. Efficient irrigation and water uses are important to sustainable development and management of water resources in the region. This paper applied DSSAT-maize v4.5 to the Yingke Irrigation District in the middle reach oasis of the Heihe River Watershed in Northwest China to explore the optimal irrigation strategies under different climatic conditions, and to improve the beneficial water consumption and reduce non-beneficial water consumption while maintaining yields at the same time. The model was first calibrated based on the crop yield, phenological phases and soil water content data, and good agreements were achieved between the simulated and observed data in both the calibration and validation periods. In the calibration period, the simulated maize phenological phases differed by two days of the observed phases, and nRMSE (normalized root mean square errors) for grain yield was 6%. In the validation period, the values of nRMSE of yield were 4.95% in 2006 and 2.96% in 2008, respectively, while the RMSE for soil water content ranged from 0.118 to 0.046. Subsequently the calibrated model was used to simulate the effects of planting dates and different irrigation treatments on maize yield and the potentially reduced water amount was calculated. Results show that in the Yingke Irrigation District, the best planting dates range from early April to mid-April, and the best irrigation periods are the jointing and tassel phases. The optimal irrigation amounts vary under different climatic conditions, ranging from about 1000 m 3 /ha, to 4200 m 3 /ha, and to 4800 m 3 /ha in wet, normal and dry years respectively. Nearly half of the irrigation amount could be reduced under the simulated irrigation schedule for the district. Once validated by field tests, the simulated irrigation scenarios would provide partial basis for effective water resources management in the study area. [ABSTRACT FROM AUTHOR]

The fluorescence properties of multi-walled carbon nanotubes (MWCNTs) depend strongly on the microstructure, while their specific surface area increases dramatically at oxidation temperatures above 75 ℃. In this work, the microstructure evolution of MWCNTs was carefully studied by oxidation and amination over a narrow temperature range to clarify its effect on the fluorescence properties. Oxidation was performed by refluxing the MWCNTs in mixtures of sulfuric acid and nitric acid at the temperature from 75 to 95 ℃. After the oxidation treatment, the MWCNTs were further aminated with ethylenediamine. The microstructure evolution at each stage was determined by the results from transmission electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The results indicate that the microstructure undergoes significantly changes over this temperature range. With the increase of temperature, the oxidized nanotubes are gradually broken and introduced defect states, but the amidation degree and fluorescence emission show a trend of first increasing and then decreasing. The MWCNTs oxidized at 85 ℃ possess the tubular structure with the length of 100–200 nm and a large number of defect states, and exhibit the optimal fluorescence efficiency after amination. What's more, the possible mechanisms involved in the effect of microstructure evolution on fluorescence were also discussed. [ABSTRACT FROM AUTHOR]