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Wetlands are important habitats on biodiversity protection. In this study, the relationship between wetland and avifauna changes in the Yellow River Delta Wetland was studied. Remote sensing and geographic information system provided an advanced platform for the research. After the avifauna survey was performed from 2012 to 2013, the birds’ variation and driving factors were analyzed. The results showed that the flow into the wetland increased continuously from 2000, and the increased of artificial wetland prevented the wetland degradation, although at the same time the total wetland area decreased. Medium grassland, tidal flat and pond are the three main landscapes which are beneficial for the habitation of birds. The migrating numbers of red-crowned crane increased significantly from 2005, and the overwintering numbers increased from 2009. The study results show that the key land use types for protecting endangered species of birds are medium grassland, tidal flat and pond landscapes. Wetland changes are sensitive to the birds and significantly affected by the flow. We suggest that the artificial wetland project should enhance the three land use type area to ensure the wetland restoration. [ABSTRACT FROM AUTHOR]

• The RSDI is suitable for monitoring aeolian desertification. • The areas with significant restoration (34.1%) exceeded those with significant deterioration (6%) in the NSPB. • In the areas with significant restoration, 57.4% of the land was mainly affected by human activities. The northern sand-prevention belt (NSPB) is the key area for sand control in China, and the various ecological projects conducted there are important to the Chinese strategy for ecological security. In this paper, a new remote sensing-based desertification index (RSDI) based on principal component analysis was constructed from four aspects of vegetation greenness, surface moisture, soil grain size, and surface radiation. The overall evaluation accuracy of the index was 89.2%, and the kappa coefficient was 0.80, indicating high sensitivity to different degrees of aeolian desertification and suitability for multiscale research. The coefficient of variation, Mann–Kendall test, Theil–Sen median trend analysis, and residual analysis were used to analyze the spatiotemporal changes and driving forces of the RSDI in the NSPB from 2000 to 2020. The RSDI was used to compare aeolian desertification in different subregions, land use types, and ecological project areas. The important results are as follows: (1) the trend of the average RSDI was downward, but it increased significantly in 2008–2009 and 2013–2014; (2) the RSDI was characterized by relatively high volatility in 28.9% and moderate volatility in 27.1% of the area; (3) the areas with significant restoration (34.1%) greatly exceeded those with significant deterioration (6%), whereas 59.9% of the total area was stable; and (4) within the area with significant restoration, 57.4% was primarily affected by human activities, and 42.4% was primarily affected by climate change; however, most of the area with significant deterioration (71.1%) was affected by human activities. In general, the degree of aeolian desertification in the NSPB has decreased in the past 20 years and its ecological quality has continued to recover. However, unreasonable human activities still need to be reduced, and the ecological management of areas under serious threat of desertification needs to be strengthened. [ABSTRACT FROM AUTHOR]

Respiratory behaviors provide useful measures of lung health. The current methods have limited capabilities of continuous characterization of respiratory behaviors, often required to assess respiratory disorders and diseases. This work presents a system equipped with a machine learning algorithm, capable of continuously monitoring respiratory behaviors. The system, consisting of two wireless wearable sensors, accurately extracts and classifies the features of respiratory behaviors of subjects within various postures, wirelessly transmitting the temporal respiratory behaviors to a laptop. The sensors were attached on the midway of the xiphoid process and the costal margin, and 1 cm above the umbilicus, respectively. The wireless wearable sensor, consisting of ultrasound emitter, ultrasound receiver, data acquisition and wireless transmitter, has a small footprint and light weight. The sensors correlate the mechanical strain at wearing sites to lung volume by measuring the local circumference changes of the chest and abdominal walls simultaneously. Eleven subjects were recruited to evaluate the wireless wearable sensors. Three different random forest classifiers, including generic, individual, and weighted-adaptive classifiers, were used to process the wireless data of the subjects at four different postures. The results demonstrate the respiratory behaviors are individual- and posture-dependent. The generic classifier merely reaches the accuracy of classifying postures of 21.9 ± 1.7% while individual and weighted-adaptive classifiers mark substantially high, up to 98.9 ± 0.6% and 98.8 ± 0.6%, respectively. The accurate monitoring of respiratory behaviors can track the progression of respiratory disorders and diseases, including chronic respiratory obstructive disease (COPD), asthma, apnea, and others for timely and objective approaches for control. • Continuously monitor and extract features of respiratory behaviors completely and accurately. • Machine-learning enabled study of individuality of respiratory behaviors. • Postures recognition based on general respiration contributing to monitor posture-related respiratory diseases, like apnea. [ABSTRACT FROM AUTHOR]

[Display omitted] • A selection strategy for base-period images of spatio-temporal fusion was proposed. • The spatio-temporal inconsistency between field samples and images was reduced. • The estimation accuracy of grassland aboveground biomass was improved. The accurate estimation of the aboveground biomass (AGB) is crucial for the sustainable utilization and management of grassland resources. Spatio-temporal inconsistencies between field samples and satellite images are major source of error in the estimation of grassland AGB. To solve this problem, this study selected the Three Rivers Headwater Region as the study area and proposed a selection strategy for base-period images of spatio-temporal fusion that was suitable for use at a large spatial scale in which cloud-free images are difficult to obtain. The spatial and temporal adaptive reflectance fusion model (STARFM) based on the selection strategy was used to generate a synthetic Normalized Difference Vegetation Index (NDVI) dataset with high spatial-temporal resolution by using the maximum value composite of GF-1 NDVI and MODIS NDVI to enhance the spatial-temporal quality of the images for field-scale application. Three estimation models for grassland AGB were then constructed by the random forest algorithm using synthetic NDVI, MODIS NDVI, GF-1 NDVI respectively, together with ancillary data. Following this, the estimation model with the highest accuracy was used to generate a 16-m eight-day time-series AGB in the growing season. The results showed: (1) The synthetic NDVI was correlated closely with the observed GF-1 NDVI, with an average R of 0.825 and a RMSE of 0.087. The temporal trend of the synthetic NDVI for each grassland type was highly consistent with that of the MODIS NDVI in the growing season with a correlation higher than 0.9. (2) The synthetic NDVI reduced the spatial difference between field samples and images to 16-fold, and the temporal difference was controlled to within four days under ideal conditions. (3) The synthetic NDVI improved the estimation accuracy of grassland AGB by about 15.9% and 19.7% (R2), and 13.7% and 17.5% (RMSE) relative to MODIS NDVI and GF-1 NDVI, respectively. (4) The time-series AGB revealed accurately the spatial distribution of and seasonal temporal variations in the grassland biomass. The results of this study may serve as scientific guidance for timely monitoring of grassland conditions and precise management of grassland resources in China. [ABSTRACT FROM AUTHOR]

Inhibition of CYP enzymes is thought to be the most common cause of drug–drug and/or herb–drug interactions. To characterize the inhibition of CYP enzymes activities by chemicals, enzyme inhibition kinetic experiments are usually carried out. The purpose of this letter is to call attention to evaluate the enzyme inhibition kinetics in drug–drug interactions. [ABSTRACT FROM AUTHOR]

Riverine wetlands provide important habitats and travel corridors for resident and transient species, playing a key role in maintaining the diversity of entire landscapes. This paper assessed a long-term (1990–2013) landscape changes and avifauna community dynamics in the Yellow River wetland natural reserves, China. Remote sensing information was combined with field surveys to collect critical data on land use and avifaunal populations. The results reveal that land use has dramatic changes during 1990–2013. Utilized water features have significantly decreased over 20 years, whereas artificial land features such as paddy, dry field and built-up area have shown a steady increasing trend in the three riverine wetlands. The spatial landscape patterns of the three wetlands have become fragmented and notably heterogeneous as results of rapid economic development. With the changes of utilized water features, avifauna data show that some overwintering and transient species are becoming permanent residents. Though there is an abundant and diverse array of bird species utilizing the wetlands, migrating traits of these avifauna species have changed. This study can provide basic information for making effective and sustainable conservation plans for the entire Yellow River wetland natural reserves. [ABSTRACT FROM AUTHOR]

[Display omitted] • The northwest area of the BTSSCP suffered severe dust-affected zones based on the dust flow trajectory. • The ESs in severe dust-affected areas were relatively poor. • ESs and the dust flow trajectory were integrated to identify ecological governance zones. • Governance suggestions were proposed for the ecological management zone combined with the driving forces. Achieving ecological conservation and governance based on ecosystem services (ESs) can balance regional ecological protection and development, which is of great significance for sustainable development. Existing research has mainly focused on the extraction of priority ecological conservation areas, thereby neglecting to consider the classification and management of ecological engineering areas. To improve regional ecological governance, we combine ESs and dust movement trajectory, using the Beijing-Tianjin Sandstorm Source Control Project (BTSSCP) as the research object to generate watersheds' ecological governance zones. Six ESs were assessed to determine ecological zones. Trajectory simulation of dust movement, using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and potential source contribution function, was used to determined zones affected by dust. By combining these two aspects, five main ecological governance clusters were identified. We found that: (1) the area with low ESs in the northwest of the BTSSCP suffered from severe dust impacts; (2) slight dust-affected zones were mainly distributed in the eastern of the BTSSCP, and in the area, ESs gradually decreased from south to north; (3) ESs in the region was primarily influenced by natural factors and the influencing factors of ESs vary among different zones. These findings will not only contribute to the overall planning and governance of the BTSSCP, but can offer general guidance for the formulation of targeted ecological protection and restoration measures in other areas. [ABSTRACT FROM AUTHOR]

Changed land use patterns are the most direct manifestation of ecological engineering implemented by humans, being among the driving factors for changes in ecosystem services (ESs). However, different ecological engineering governance measures can lead to different changes in land use, resulting in corresponding changes to ESs and ecosystem service value (ESV), yet these changes is the content that needs to be clarified. In this study, four kinds of ESs, namely water yield, soil conservation, carbon storage and water purification, were quantified in part region of the Beijing-Tianjin Sandstorm Source Control Project (BTSSCP). In addition, eight scenarios were simulated according to the land use change caused by engineering management measures, and the ESs and ESV ensuing under these differing scenarios quantified accordingly. The results show that the main land use types in the study area from 2000 to 2020 were cropland and forestland, while during this period land use change mainly consisted of the expansion of grassland (+466.79 km2) and loss of cropland (−2095.27 km2). For different engineering management measures, protective governance will play a greater role in improving ESs than restoration governance. Protecting the existing governance outcomes from degrading can maintain a water yield of 36.85 × 108 m3, soil conservation of 73.72 × 106 t, carbon storage of 89.01 × 106 t, the purified water nitrogen content of 1.21 × 106 t, with the total ESV maintained at 54.237 billion yuan. Moreover, the high-investment counties clearly engage in ecological restoration that provides high ESV. Yet, there are still some counties with high project investment where the gains in ESV are low, such as Luanping county and Pingquan county. Therefore, it should be reasonably distributed based on the existing governance results in the next round of project investment allocation. In the past 20 years, engineering governance measures have significantly improved the ESs in the region. Nevertheless, looking ahead, it remains necessary to strengthen the emphasis on protecting governance outcomes. [Display omitted] • Scenario simulations were run under governance measures for ecological engineering. • Ecosystem service value (ESV) under differing governance measures were simulated. • ESV is higher when ecological protection rather than restoration measures are used. • Project investment vis-à-vis ESV under the different scenarios were analyzed. [ABSTRACT FROM AUTHOR]

A long-term stability of gel enhanced foam as an in-depth profile control agent in high temperature reservoirs was successfully prepared by adding comb polymer gel. The increased viscosity of gel brings a negative effect on surface tension which reduces the gel enhanced foam volume. In turn, the increased viscosity could enhance the thickness and strength of foam film which increases foam stability and plugging capacity in porous media. The morphology results show that the gel enhanced foam has a thicker bubble film which enhances its foam stability. The effect of injection mode, gas–liquid ratio, gas injection velocity and formation permeability on the plugging capacity was investigated by single sand-pack experiments. When the gas–liquid ratio and gas injection velocity were respectively set at 1:1 and 0.5 ml/min, co-injection of gel enhanced foaming solution and gas could obtain a better plugging capacity in high permeability sand-packs. Parallel sand-pack experiments show that the profile improvement capacity of high formation permeability ratio is much better than that of low formation permeability ratio. The visual simulation experiment was also conducted to illustrate the flowing behavior of gel enhanced foam. By Jiamin effect or Jamin superimposed effect, directly plugging and bridging in the large pore space, the gel enhanced foam can effectively reduce the permeability of porous media in high permeability zones and divert fluid into low permeability zones, thus increases the swept volume. The treatment has been successfully used in Henan oilfield of China which provides a reference to water production control in other similar high temperature oilfields. [ABSTRACT FROM AUTHOR]

A numerical study with large-eddy simulation (LES) method is performed on the aerodynamic effects of bio-inspired leading-edge serrations on a wing in heaving motion at a low Reynolds number of Re = 2 × 10 4. During the research, rigorous contrastive simulations are performed for the baseline wing and the serrated ones. The baseline wing has a NACA0012 profile and the serrated ones are obtained by stretching/shrinking the leading portion of the baseline sinusoidally. Conclusive results show that leading-edge serrations can help reduce aerodynamic hysteresis and suppress dynamic-stall-induced load oscillations effectively. More importantly, serrated wings can be more efficient in lift production than the baseline, especially for relatively high reduced frequencies. In the currently covered parameter space, the largest lift efficiency improvement achieved by the leading-edge serrations can reach 15.92%, and the least improvement is 2.73%. Along with these good properties, the leading-edge serrations have induced larger drag, which indicates they are undesirable for propulsive motivations. Visualization of the flow fields reveals that a series of counter-rotating streamwise vortex pairs are dynamically induced by the leading-edge serrations. These streamwise vortices can act as momentum transporters and help enhance momentum exchange between low-energy boundary layer and high-energy outer flows, which can affect the flow structures as well as the aerodynamics of a heaving wing greatly. The current results may provide inspirations for improving aerodynamics, economies and stabilities of bionic underwater/aerial micro robots or any other devices which have heaving/flapping parts. [ABSTRACT FROM AUTHOR]

Renal ischemia/reperfusion and ATP depletion/repletion in LLC-PK[sub 1] cells result in phosphorylation of FKHR and FKHRL1. Background. Cell death and survival pathways are critical determinants of epithelial cell fate after ischemia. Forkhead proteins have been implicated in the regulation of cellular survival. Methods and Results. We have found that none of the forkhead family of proteins, FKHR, is phosphorylated after ischemia/reperfusion in the rat kidney. The time course of phosphorylation is similar to the time course of activation of the forkhead protein kinase Akt/protein kinase B (PKB), with maximal phosphorylation at 24 to 48 hours postreperfusion when the process of regeneration peaks. Extracellular signal-regulated kinase (ERK)1/2 activation has also been implicated as prosurvival in the injured kidney. ERK1/2 were phosphorylated in postischemic kidneys at 5, 30, and 90 minutes of reperfusion, with phosphorylation decreased by 24 and 48 hours. Immunocytochemical analysis revealed increased phospho-ERK1/2 in the thick ascending limb and isolated cells of the S3 segment, which have lost apical actin staining. To understand the relationship between forkhead phosphorylation, Akt, and ERK1/2, an in vitro model of injury was employed. After 40 minutes of chemical anoxia followed by dextrose addition for 20 minutes to replete adenosine triphosphate (ATP) levels, FKHR and FKHRL1 are phosphorylated. The levels of phospho-Akt are increased for at least 120 minutes after dextrose addition with a maximum at 20 minutes. Phosphorylation of Akt, FKHR, and FKHRL1 are phosphatidylinositol 3-kinase (PI 3-kinase) dependent since phosphorylation is reduced by the PI 3-kinase inhibitors, wortmannin, or LY294002. Inhibition of mitogen-activated protein kinase (MAPK)/ERK kinase (MEK1/2), the upstream activator of ERK1/2, has no effect on forkhead protein phosphorylation after chemical anoxia/dextrose addition. Conclusion. We conclude that PI 3-kinase and Akt are activated after renal ischemia/reperfusion and that Akt phosphorylation leads to phosphorylation of FKHR and FKHRL1, which may affect epithelial cell fate in acute renal failure. [ABSTRACT FROM AUTHOR]