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ESA's Soil Moisture Ocean Salinity (SMOS, since 2009) and NASA's Soil Moisture Active Passive (SMAP, since 2015) are the only two space-borne L-band radiometer missions currently in orbit, which provide key information on global surface soil moisture (SM) and vegetation water content (via the vegetation optical depth, VOD). However, to date very few studies considered merging SMOS and SMAP for both SM and VOD retrievals simultaneously. This study presents the first global long-term and continuous SM and L-band VOD (L-VOD) dataset retrieved after merging the SMOS and SMAP brightness temperature (TB) observations, called the SMOS-SMAP-INRAE-BORDEAUX or SMOSMAP-IB product. We first developed a fitted SMOS TB dataset at a fixed incidence angle of 40°, and next applied a monthly linear rescaling of SMAP TB to SMOS TB for each polarization to produce a merged SMOS/SMAP TB (θ = 40°) dataset. The retrievals were then based on a mono-angular retrieval algorithm sharing a similar forward model with the SMOS-IC and the official SMOS retrieval algorithms. Results showed that the inter-calibration approach we used here could effectively remove the bias between the SMAP TB and fitted SMOS TB, with bias values reduced to 0.01 K (−0.02 K) compared to 3.45 K (1.65 K) for V (H) polarization before inter-calibration. The SMOSMAP-IB SM and L-VOD retrievals based on this new inter-calibrated SMOS/SMAP TB led to metrics that were equally good or better than those of other products (i.e., ESA CCI, SMOS-IC and the official SMAP products). When considering only long duration products, SMOSMAP-IB SM retrievals exhibited (i) the highest overall median R value of 0.72 with in-situ data from ISMN (International Soil Moisture Network) during 2013–2018, followed by SMOS-IC (R = 0.68) and CCI (R = 0.67), and (ii) the same smallest ub RMSD values as CCI (ub RMSD = 0.057 m3/m3 vs 0.061 m3/m3 for SMOS-IC). L-VOD retrievals from SMOSMAP-IB were found to have comparable spatial and temporal skills to SMOS-IC. Spatially, they both correlated well with aboveground biomass (R = 0.87), and temporally, they both showed a good representation of the short vegetation NDVI signal and of the forest area loss in the Brazilian Amazon from 2011 to 2019. Developing SMOSMAP-IB is a step forward towards building a time-continuous L-band SM and VOD products in response to the possible failure of one of the SMOS or SMAP sensors in the future. • The first SM and L-VOD product (SMOSMAP-IB) that fuses SMOS and SMAP is proposed. • SMOSMAP-IB SM correlates better with in-situ data than other retrieval products. • SMOSMAP-IB SM has similar ub RMSD skill scores as CCI SM. • SMOSMAP-IB L-VOD has comparable spatial and temporal skills as SMOS-IC L-VOD. [ABSTRACT FROM AUTHOR]

High-quality and long-term surface soil moisture (SSM) and root-zone soil moisture (RZSM) data are critical for agricultural water management of Jiangsu province, which is a major agricultural province in China. However, few studies assessed the accuracy of SSM and RZSM datasets in croplands of Jiangsu province. The study addressed this gap by firstly using observations from ninety-one sites to assess thirteen satellite and model-based SSM products (Advanced Scatterometer (ASCAT), European Space Agency Climate Change Initiative (ESA CCI) Combined/Passive/Active, Soil Moisture and Ocean Salinity in version IC (SMOS-IC), Land Parameter Retrieval Model (LPRM) Advanced Microwave Scanning Radiometer 2 (AMSR2), Soil Moisture Active Passive (SMAP)-Multi-Temporal Dual-channel Algorithm (MTDCA)/Level 3 (L3)/Level 4 (L4)/SMAP-INRAE-BORDEAUX (IB)/Multi-channel Collaborative Algorithm (MCCA), the fifth generation of the land component of the European Centre for Medium-Range Weather Forecasts atmospheric reanalysis (ERA5-Land), and the Noah land surface model driven by Global Land Data Assimilation System (GLDAS-Noah)), and four RZSM products (ERA5-Land, GLDAS-Noah, SMAP-L4 and ESA CCI (retrieved using ESA CCI Combined SSM coupled with an exponential filter)). We also inter-compared time-invariant and time-variant Triple Collocation Analysis (TCA)-based R with in situ -based R calculated using SSM anomalies. Various evaluation strategies were compared using different groups of available sites and temporal samplings. Our results showed that the model-based and combined SSM products (i.e. , ERA5-Land, SMAP-L4, ESA CCI Combined/Passive/Active, GLDAS-Noah, ASCAT) performed better than the other SSM products and ERA5-Land, SMAP-L4 and ESA CCI RZSM generally performed better than the GLDAS-Noah RZSM product with higher R. Similar performance rankings were observed among time-invariant and time-variant TCA- R and in situ -based R , in which the TCA- R values for all SSM datasets were higher than the in situ -based R as the representativeness errors of the in situ measurements may bias in situ -based R. The accuracy of the ESA CCI, GLDAS-Noah and ERA5-Land SSM products was expected to be enhanced by considering the water effect and high uncertainties were observed for MTDCA and SMAP-MCCA SSM over dense vegetation periods and regions. Also, it is important to select appropriate evaluation strategies to conduct the SSM and RZSM evaluations according to the situation as the available sites and temporal samplings may bias the evaluation results. • SSM and RZSM products were evaluated over croplands of Jiangsu province. • Reanalysis products outperformed other SSM and RZSM products over croplands. • Similar performances were found for time-invariant/variant TCA- R and in situ -based R. • The impacts of WF, VOD and data samplings on SSM products' accuracy were studied. [ABSTRACT FROM AUTHOR]

• Three cooperative wake control strategies for wind farms are symmetrically studied. • A regular and an irregular realistic wind farm are taken as the research objectives. • The performances are analyzed in the full wind directions under three wind speeds. • The combined control strategy outperforms the only yaw and only induction control. The wake regulation by cooperative yaw control, axis induction control, or their combination can significantly improve the total power output of wind farms. However, a comprehensive study of the three control strategies is still lacking, which hinders their engineering applications. To this end, the optimized yaw angles, induction factors, and total power promotion are systematically compared for the three control strategies on both a regularly arranged wind farm and an irregularly arranged realistic offshore wind farm. The results indicate that all the three strategies work similarly to achieve a net power gain by enhancing the power output of the downstream turbines while slightly downgrading the upstream turbines. For the regularly arranged wind farm, very notable power promotions are obtained in the aligned direction, and all the three control strategies show similar performance, but the promotions almost disappear with a small misalignment. In contrast, power promotion is less sensitive to the wind direction for the irregularly arranged wind farm. The promotion of the yaw control is much more predominate than that of the induction control, and the combined control only slightly outperforms the single yaw control in the realistic wind farm. In the prevailing wind direction, the total power of the realistic wind farm can be increased by 2.1% by the combined control strategy under the wind speed of 6 m/s. [ABSTRACT FROM AUTHOR]

• A downscaling framework for generating 1 km seamless and daily SSM was proposed. • The proposed framework was inspired by point-surface fusion through deep learning. • Downscaled SSM showed excellent spatial and temporal patterns against in-situ SSM. • Downscaled SSM showed higher accuracy than original SMAP SSM and ERA5-Land SSM. Surface soil moisture (SSM) is of great importance in understanding global climate change and studies related to environmental and earth science. However, neither of current SSM products or algorithms can generate SSM with High spatial resolution, High spatio-temporal continuity (cloud-free and daily), and High accuracy simultaneously (i.e., 3H SSM data). Without 3H SSM data, fine-scale environmental and hydrological modeling cannot be easily achieved. To address this issue, we proposed a novel and integrated SSM downscaling framework inspired by deep learning-based point-surface fusion, which was designed to produce 1 km spatially seamless and temporally continuous SSM with high accuracy by fusing remotely sensed, model-based, and ground data. First, SSM auxiliary variables (e.g., land surface temperature, surface reflectance) were gap filled to ensure the spatial continuity. Meanwhile, the extended triple collocation method was adopted to select reliable in-situ stations to address the scale mismatch issue in SSM downscaling. Then, the deep belief model was utilized to downscale the original 9 km SMAP SSM and 0.1º. ERA5-Land SSM to 1 km. The downscaling framework was validated over three ISMN soil moisture networks covering diverse ground conditions in Southwestern US. Three validation strategies were adopted, including in-situ validation, time-series validation, and spatial distribution validation. Results showed that the average Pearson correlation coefficient (PCC), unbiased root mean squared error (ubRMSE), and mean absolute error (MAE) achieved 0.89, 0.034 m 3 m − 3 , and 0.032 m 3 m − 3 , respectively. The use of point-surface fusion greatly improved the downscaling accuracy, of which the PCC, ubRMSE, and MAE were improved by 3.73, 20.93, and 39.62% compared to surface-surface fusion method, respectively. Comparative analyses have also been carefully conducted to confirm the effectiveness of the framework, in terms of other downscaling algorithms, scale variations, and fusion methods. The proposed method is promising for fine-scale studies and applications in agricultural, hydrological, and environmental domains. [ABSTRACT FROM AUTHOR]

Reductive soil disinfestation (RSD) and biochar amendment are considered sustainable management practices to improve degraded vegetable soil. However, the combined effects of these two remediation methods on soil microbial communities and vegetable yields remain unclear. In the present field study, the interactive impacts of conventional RSD treatment and biochar were tested in plastic greenhouse soils under a continuous vegetable cultivation system. Six treatments consisted of different management practices: soil untreated (CK), soil amended with biochar (BC), soil flooded (SF), soil flooded and mulched with plastic film (SFM), soil amended with alfalfa residue, flooded and mulched with plastic film (RSD), and soil amended with alfalfa residue plus biochar, flooded and mulched with plastic film (RSD+BC). Analysis of the soil samples collected at 0–20 cm for a range of physicochemical and microbial properties revealed that both RSD and RSD+BC treatments decreased soil nitrate (NO 3 -) concentrations while increasing soil pH, ammonium (NH 4 +), dissolved organic carbon (DOC), and the low-valent ion (Fe2+, Mn2+) concentrations (P < 0.05). Unlike the BC, SF and SFM treatments, the RSD and RSD+BC treatments decreased the bacterial and fungal diversity (P < 0.05) compared to the CK, and altered microbial community composition. The RSD treatment significantly reduced the relative abundance of genus Fusarium while increasing the relative abundances of genera Bacillus and Clostridium , and the increase was more evident in the RSD+BC treatment, suggesting the potential of the latter to suppress pathogenic fungi while increasing beneficial bacteria. The structural equation model revealed the key role of soil redox potential (Eh) and NH 4 + concentration in the regulation of microbial community composition. Furthermore, BC, RSD, and RSD+BC treatments increased pepper yield by 27.4%, 55.3% and 44.4%, respectively, compared to CK. The yield of pepper was positively correlated with the contents of DOC, NH 4 +, and the relative abundance of Bacillus and Clostridium in soil (P < 0.01), and negatively correlated with NO 3 - and relative abundance of Fusarium (P < 0.05). This study provides evidence for the efficiency of the combined application of RSD and biochar to amend the quality of degraded soils in plastic sheds under continuous cultivation. • RSD and RSD+BC treatments created strongly reductive soil conditions. • RSD and RSD+BC methods modified microbial community composition. • Microbial community composition was regulated by soil Eh and NH 4 + concentration. • RSD, BC, and RSD+BC practices increased the yield of pepper than CK. [ABSTRACT FROM AUTHOR]

Passive microwave remote sensing at L-band (1.4 GHz) provides an unprecedented opportunity to estimate global surface soil moisture (SM) and vegetation water content (via the vegetation optical depth, VOD), which are essential to monitor the Earth water and carbon cycles. Currently, only two space-borne L-band radiometer missions are operating: the Soil Moisture and Ocean Salinity (SMOS) and the Soil Moisture Active Passive (SMAP) missions in orbit since 2009 and 2015, respectively. This study presents a new mono-angle retrieval algorithm (called SMAP-INRAE-BORDEAUX, hereafter SMAP-IB) of SM and L-band VOD (L-VOD) from the dual-channel SMAP radiometric observations. The retrievals are based on the L-MEB (L-band Microwave Emission of the Biosphere) model which is the forward model of SMOS-IC and of the official SMOS retrieval algorithms. The SMAP-IB product aims at providing good performances for both SM and L-VOD while remaining independent of auxiliary data: neither modelled SM data nor optical vegetation indices are used as input in the algorithm. Inter-comparison with other SM and L-VOD products (i.e., MT-DCA, SMOS-IC, and the new versions of DCA and SCA-V extracted from SMAP passive Level 3 product) suggested that SMAP-IB performed well for both SM and L-VOD. In particular, SMAP-IB SM retrievals presented the higher scores (R = 0.74) in capturing the temporal trends of in-situ observations from ISMN (International Soil Moisture Network) during April 2015–March 2019, followed by MT-DCA (R = 0.71). While the lowest ub RMSD value was obtained by the new version of SMAP DCA (0.056 m3/m3), SMAP-IB SM retrievals presented best scores for R, ub RMSD (~ 0.058 m3/m3) and bias (0.002 m3/m3) when considering only products independent of optical vegetation indices (e.g., NDVI). L-VOD retrievals from SMAP-IB, MT-DCA, and SMOS-IC were well correlated (spatially) with aboveground biomass and tree height, with spatial R values of ~0.88 and ~ 0.90, respectively. All three L-VOD products exhibited a smooth non-linear density distribution with biomass and a good linear relationship with tree height, especially at high biomass levels, while the L-VOD datasets incorporating optical information in the algorithms (i.e., SCA-V and DCA) showed obvious saturation effects. It is expected that this new algorithm can facilitate the fusion of both SM and L-VOD retrievals from SMOS and SMAP to obtain long-term and continuous L-band earth observation products. • A new algorithm (SMAP-IB) is proposed for the retrieval of SM and L-VOD from SMAP. • Performances of SMAP-IB SM and L-VOD are inter-compared with four other products. • SMAP-IB SM showed best scores for correlation and similar to SCA-V for ub RMSD. • SMAP-IB L-VOD showed high scores according to all used criteria. [ABSTRACT FROM AUTHOR]

• Impact of TGD construction on drought propagation process were quantified. • Propagation of drought duration and severity were aggravated after TGD operation. • Hydrological drought and soil moisture drought propagation speed was affected. • Potential influence factors were explored at different periods from 1981 to 2020. The construction of Three Gorges Dam (TGD) has exerted substantial effects on local hydrological regime and eco-system since its operation in 2003. Due to this significant anthropogenic activity, drought propagation processes from Meteorological drought to Hydrological (M-H) and Soil moisture (M-S) drought are inevitably modified. However, current studies are still insufficient to answer whether the TGD operation mitigated or exacerbated the drought propagation process due to its complex impacts. To explore this key issue, this study proposed an integrated framework to quantify the impact of TGD construction on drought propagation process in the Yangtze River Basin (YRB). The drought characteristics propagation models and propagation time were calculated to identify the modification of drought propagation process between different TGD operation scenarios. Trend and attribution analyses were also utilized to explore potential influence factors. Results demonstrated that TGD construction did significantly aggravate the drought characteristics propagation. Specifically, the slopes of hydrological drought duration and severity in linear propagation models increased 23.98% and 29.23% in average. While for M-S propagation, the slopes of duration and severity models increased 28.72% and 21.91%, respectively. This research also found that, after TGD operation, the M-H propagation speed had been slowed down but the M-S lag time became shorter. Additionally, the variations and trend patterns of six potential influence factors at four separate periods were full analyzed to provide implications for the drought propagation modifications. And TGD operation was confirmed to become a major factor inducing the variations of annual runoff, which accounted for 56.75% for the entire YRB. The above quantitative findings are expected to reveal the potential changes of drought propagation process caused by the construction of TGD in YRB. The proposed integrated framework is also beneficial to the drought early warning system and understanding of drought development not only in YRB, but also in other basins at the global scale. [ABSTRACT FROM AUTHOR]

A polarization beam splitter (PBS) based on an asymmetrical Mach-Zehnder interferometer (MZI) is experimentally demonstrated on a InP platform. The experimental results show that the polarization extinction ratios (PERs) are 8 dB and 14 dB for transverse-electric (TE) and transverse-magnetic (TM) polarization at 1550 nm, respectively. The PER is greater than 5 dB/12 dB for TE/TM polarization over the full C band wavelength range. Fabrication errors including the waveguide width, arm length, film thickness, and sidewall are analyzed using the beam propagation method. The width and sidewall are the most sensitive factors that affect the performances of this type of PBS. This analysis will improve the fabrication tolerance of the PBS. • Deep ridge waveguide make the chip compact. • Beam propagation method is used to analyze the fabrication errors. • The waveguide size, film thickness, and sidewall influences are analyzed. • The error analysis will help improve the fabrication tolerance. [ABSTRACT FROM AUTHOR]

In this study, an online antioxidant assay based on HPLC-ABTS was mainly developed for screening the antioxidants of flavonoids from Astragali Radix (AR), and comparing the antioxidant capacity between traditional decoction pieces (TDP) of AR and cell wall-broken decoction pieces (CDP) of AR. The experimental results showed that the overall antioxidant capacity of CDP of AR was about twice as much as that of TDP of AR, which was specifically expressed as the antioxidant capacity of the screened antioxidants extracted from CDP was equivalent to 1.9-5.1 times that of those extracted from TDP, and three antioxidants were successfully screened, which were calycosin-7-O-β-D-glucoside, calycosin, and formononetin. The method established in this study is characterized by high efficiency and accuracy, which can simultaneously accomplish the screening of antioxidant components and the comparison of antioxidant capacity between samples, and provides a new method for the quality evaluation of AR from the perspective of antioxidant activity., (© 2024 John Wiley & Sons Ltd.)

Humidity sensors have been widely used to monitor humidity in daily life, agriculture fields, and so on. However, conventional sensors are not suitable for wearable devices because of their large dimensions and rigid substrates. Hence, we report a fast response, highly sensitive, and fully flexible humidity sensor on a PI substrate based on the composite material of reduced graphene oxide (rGO)/MoS 2 , with a response time of 0.65 s and a sensitivity of 96.7% in the relative humidity range of 11% RH-95% RH. A fully flexible wearable device was realized by integrating the prepared flexible humidity sensor with a flexible printed circuit, which was successfully applied for human breathing monitoring, motion monitoring, and nontouch switches. These results show that the rGO/MoS 2 composite is a good candidate for humidity sensing and has the potential to be used in the fields of wearable devices and nontouch switching.

Low solar irradiance reaching the canopy due to fog and heavy haze is a significant yield-limiting factor worldwide. However, how plants adapt to shade stress and the mechanisms underlying the reduction in leaf photosynthetic capacity and grain yield remain unclear. In this study (conducted during 2018-2021), we investigated the impact of light deprivation (60%) at the pre-anthesis and post-anthesis stages on leaf carboxylation efficiency, source-to-sink relationships, sucrose metabolism, and grain yield of wheat cultivars with contrasting shade tolerance. Shade stress decreased stomatal conductance, stomatal limitation value, intrinsic water use efficiency, rubisco activity, and carboxylation efficiency of flag leaves during grain-filling, whereas intercellular CO 2 concentration increased. These findings indicate that non-stomatal limitation reduces the net photosynthesis rate in a weak-light environment. Shade-tolerant cultivars (MM-51 and CM-39) adapted to low-light conditions via a higher leaf area of flag leaves, light interception rate, and chlorophyll a and b contents; this increased non-structural carbohydrates and sucrose contents in developing grains, ultimately decreasing yield loss by shade stress. Pre-anthesis shading resulted in a greater yield loss than post-anthesis shading because of decreased plant biomass, grain number per spike and 1,000-kernel weight. This study indicates that Rubisco-mediated non-stomatal limitation reduces P N and sucrose content in plants exposed to low-light stress, contributing to decreased grain yield. Our study provides information on the mechanism underlying shade stress tolerance, which will help design future strategies for reducing yield loss in the context of global dimming., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Zhao, Ma, Pu, Zhang, Huang, Yang and Fan.)

A double-channel methane (CH 4 ) sensor was developed using a dual-pass multipass cell (DP-MPC) and a novel method that combines averaging dual-channel concentration signals with optimized detector gain configuration. This DP-MPC features two input/output coupling holes, resulting in absorption path lengths of approximately 95.8 m and 35.8 m, respectively. By optimizing the photodetector gain configuration and averaging the dual-channel concentration signals, the detection performance of the sensor was further enhanced. Allan deviation analysis indicated that after optimizing the detector gain, the measurement precision after dual-channel averaging reaches 21 ppb with an integration time of 1 s at a concentration of 2 ppm CH 4 , which is approximately 1.4 times higher than the measurement precision of the long-path channel (31 ppb) and short-path channel (30 ppb). The time required to achieve a measurement precision of 21 ppb is 2.4 s for the long-path channel and 2.1 s for the short-path channel. The response speed of the dual-channel averaging is approximately 2 times that of any single channel. Meanwhile, the sensor demonstrated its stability and reliability through continuous outdoor atmospheric CH 4 measurements.

Graphene is being increasingly used as an interesting transducer membrane in micro- and nanoelectromechanical systems (MEMS and NEMS, respectively) due to its atomical thickness, extremely high carrier mobility, high mechanical strength, and piezoresistive electromechanical transductions. NEMS devices based on graphene feature increased sensitivity, reduced size, and new functionalities. In this review, we discuss the merits of graphene as a functional material for MEMS and NEMS, the related properties of graphene, the transduction mechanisms of graphene MEMS and NEMS, typical transfer methods for integrating graphene with MEMS substrates, methods for fabricating suspended graphene, and graphene patterning and electrical contact. Consequently, we provide an overview of devices based on suspended and nonsuspended graphene structures. Finally, we discuss the potential and challenges of applications of graphene in MEMS and NEMS. Owing to its unique features, graphene is a promising material for emerging MEMS, NEMS, and sensor applications., (© 2024. The Author(s).)

Graphene oxide (GO)-based humidity sensors are attracting widespread attention due to their high responsivity and low cost. However, GO-based humidity sensors generally suffer from slow response and recovery as well as poor stability. Here, we report a flexible resistive humidity sensor based on a MoS 2 /GO composite film that was fabricated by mixing different volumes of MoS 2 and GO dispersions with adjustable volume ratios. The MoS 2 /GO composite film has been used as a sensing layer on screen-printed interdigital electrodes. The results show that the best device performance was achieved at a dispersion volume of 0.05 mL with a MoS 2 /GO volume ratio of 5 : 1, featuring a high responsivity (∼98%), a fast response/recovery time (1.3/12.1 s), excellent stability and low cost. Furthermore, the humidity sensor exhibits good linearity over a wide humidity range (33%RH-98%RH) at room temperature (25 °C) and can be fabricated easily and feasibly. The application of the humidity sensors we prepared in human respiration detection and human fingertip proximity detection has been demonstrated. These findings indicate the great potential of the MoS 2 /GO composite in developing next generation high-performance humidity sensors.

Graphene has great potential to be used for humidity sensing due to its ultrahigh surface area and conductivity. However, the impact of different atomic layers of graphene on the SiO 2 /Si substrate on humidity sensing has not been studied yet. In this paper, we fabricated three types of humidity sensors on the SiO 2 /Si substrate based on one to three atomic layers of graphene, in which the sensing areas of graphene are 75 μm × 72 μm and 45 μm × 72 μm, respectively. We studied the impact of both the number of atomic layers of graphene and the sensing areas of graphene on the responsivity and response/recovery time of the prepared graphene-based humidity sensors. We found that the relative resistance change of the prepared devices decreased with the increase of number of atomic layers of graphene under the same change of relative humidity. Further, devices based on tri-layer graphene showed the fastest response/recovery time, while devices based on double-layer graphene showed the slowest response/recovery time. Finally, we chose devices based on double-layer graphene that have relatively good responsivity and stability for application in respiration monitoring and contact-free finger monitoring.

Rosmarinic acid (RA), Tanshinone IIA (Tan IIA), and Salvianolic acid B (Sal B) are crucial compounds found in Salvia miltiorrhiza. Quickly predicting these components can aid in ensuring the quality of S. miltiorrhiza. Spectral preprocessing and variable selection are essential processes in quantitative analysis using near infrared spectroscopy (NIR). A novel hybrid variable selection approach utilizing iVISSA was employed in this study to enhance the quantitative measurement of RA, Tan IIA, and Sal B contents in S. miltiorrhiza. The spectra underwent 108 preprocessing approaches, with the optimal method being determined as orthogonal signal correction (OSC). iVISSA was utilized to identify the intervals (feature bands) that were most pertinent to the target chemical. Various methods such as bootstrapping soft shrinkage (BOSS), competitive adaptive reweighted sampling (CARS), genetic algorithm (GA), variable combination population analysis (VCPA), successive projections algorithm (SPA), iteratively variable subset optimization (IVSO), and iteratively retained informative variables (IRIV) were used to identify significant feature variables. PLSR models were created for comparison using the given variables. The results fully demonstrated that iVISSA-SPA calibration model had the best comprehensive performance for Tan IIA, and iVISSA-BOSS had the best comprehensive performance for RA and Sal B, and correlation coefficients of cross-validation (R 2 cv), root mean square errors of cross-validation (RMSECV), correlation coefficients of prediction (R 2 p), and root mean square errors of prediction (RMSEP) were 0.9970, 0.0054, 0.9990 and 0.0033, 0.9992, 0.0016, 0.9961 and 0.0034, 0.9998, 0.0138, 0.9875 and 0.1090, respectively. The results suggest that NIR spectroscopy, along with PLSR and a hybrid variable selection method using iVISSA, can be a valuable tool for quickly quantifying RA, Sal B, and Tan IIA in S. miltiorrhiza., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ethics approval and consent to participate: This study did not involved human participants and animals, and not applicable in this section. Consent for publication: This manuscript does not contain data from any individual person, and not applicable in this section. Competing interests: All co-authors have seen and agree with the contents of the manuscript and there is no financial interest to report. Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. Code availability: Not applicable., (Copyright © 2024 Elsevier B.V. All rights reserved.)

During extensive periods without rain, known as dry-downs, decreasing soil moisture (SM) induces plant water stress at the point when it limits evapotranspiration, defining a critical SM threshold (θ crit ). Better quantification of θ crit is needed for improving future projections of climate and water resources, food production, and ecosystem vulnerability. Here, we combine systematic satellite observations of the diurnal amplitude of land surface temperature (dLST) and SM during dry-downs, corroborated by in-situ data from flux towers, to generate the observation-based global map of θ crit . We find an average global θ crit of 0.19 m 3 /m 3 , varying from 0.12 m 3 /m 3 in arid ecosystems to 0.26 m 3 /m 3 in humid ecosystems. θ crit simulated by Earth System Models is overestimated in dry areas and underestimated in wet areas. The global observed pattern of θ crit reflects plant adaptation to soil available water and atmospheric demand. Using explainable machine learning, we show that aridity index, leaf area and soil texture are the most influential drivers. Moreover, we show that the annual fraction of days with water stress, when SM stays below θ crit , has increased in the past four decades. Our results have important implications for understanding the inception of water stress in models and identifying SM tipping points., (© 2024. The Author(s).)

Although wheat (Triticum aestivum L.) grain protein content is increased by shade stress, the relationship between the baking quality of wheat flour and protein composition and structure remains unclear. Here, we investigated the effects of shade stress on wheat flour protein composition and structure. The contents of the flour protein, α/β-gliadins and disulfide and hydrogen bonds were significantly increased by shade stress. Glutenins, UPP%, and β-sheet contents also increased, whereas that of α-helices decreased. Spearman correlations revealed that the flour protein content, Glu:Gli ratio, and disulfide, hydrogen, and ionic bonds can predict the specific volume and number of crumb cells in bread, whereas α/β-gliadins content can predict the crumb cell wall thickness and diameter of bread. Under shade stress, variations in protein composition and structure help increase the specific volume and crumb cells number and decrease crumb cell wall thickness and diameter of bread, ultimately leading to improved baking quality., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Purpose: This study aimed to investigate the risk factors for liver disease comorbidity among older adults in eastern, central, and western China, and explored binary, ternary and quaternary co-morbid co-causal patterns of liver disease within a health ecological model., Method: Basic information from 9,763 older adults was analyzed using data from the China Health and Retirement Longitudinal Study (CHARLS). LASSO regression was employed to identify significant predictors in eastern, central, and western China. Patterns of liver disease comorbidity were studied using association rules, and spatial distribution was analyzed using a geographic information system. Furthermore, binary, ternary, and quaternary network diagrams were constructed to illustrate the relationships between liver disease comorbidity and co-causes., Results: Among the 9,763 elderly adults studied, 536 were found to have liver disease comorbidity, with binary or ternary comorbidity being the most prevalent. Provinces with a high prevalence of liver disease comorbidity were primarily concentrated in Inner Mongolia, Sichuan, and Henan. The most common comorbidity patterns identified were "liver-heart-metabolic", "liver-kidney", "liver-lung", and "liver-stomach-arthritic". In the eastern region, important combination patterns included "liver disease-metabolic disease", "liver disease-stomach disease", and "liver disease-arthritis", with the main influencing factors being sleep duration of less than 6 h, frequent drinking, female, and daily activity capability. In the central region, common combination patterns included "liver disease-heart disease", "liver disease-metabolic disease", and "liver disease-kidney disease", with the main influencing factors being an education level of primary school or below, marriage, having medical insurance, exercise, and no disabilities. In the western region, the main comorbidity patterns were "liver disease-chronic lung disease", "liver disease-stomach disease", "liver disease-heart disease", and "liver disease-arthritis", with the main influencing factors being general or poor health satisfaction, general or poor health condition, severe pain, and no disabilities., Conclusion: The comorbidities associated with liver disease exhibit specific clustering patterns at both the overall and local levels. By analyzing the comorbidity patterns of liver diseases in different regions and establishing co-morbid co-causal patterns, this study offers a new perspective and scientific basis for the prevention and treatment of liver diseases., (© 2024. The Author(s).)

Over the past several decades, a decreasing trend in solar radiation has been observed during the wheat growing season. The effects of shade stress on grain yield formation have been extensively studied. However, little information on shade stress's effects on protein formation warrants further investigation. Two wheat cultivars were grown under three treatments, no shade as the control group (CK), shading from the joint to the anthesis stage (S1), and shading from the joint to the mature stage (S2), to investigate the effects of shade stress on the free amino acids of the caryopsis and endosperm and protein accumulation during grain filling. The dry mass of caryopsis and endosperm was significantly decreased under shade stress, whereas Glu, Ser, Ala, and Asp and protein relative content increased during grain filling. The observed increases in total protein in S1 and S2 were attributed to the increases in the SDS-isoluble and SDS-soluble protein extracts, respectively. S1 improved polymer protein formation, but S2 delayed the conversion of albumins and globulins into monomeric and polymeric proteins. Moreover, shade stress increased the proportion of SDS-unextractable polymeric protein, which represented an increase in the degree of protein polymerization. The polymerization of protein interrelations between protein components and accumulation in caryopsis and endosperm provided novel insights into wheat quality formation under shade stress., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ma, Yang, Wu, Xiang, Luo, Huang, Yang, Zheng and Fan.)

Alterations in the gut microbiome have been linked to obesity and type 2 diabetes, in epidemiologic studies and studies of fecal transfer effects in germ-free mice. Here, we aimed to identify the effects of specific gut microbes on the phenotype of mice fed a high-fat diet (HFD). After eight weeks of HFD feeding, male C57BL/6J mice in the HFD group ranking in the upper and lower quartiles for body weight gain were considered obese prone and obese resistant, respectively. 16S rRNA gene sequencing was used to determine the composition of the intestinal microbiota, and fecal transplantation (FMT) was conducted to determine whether the microbiota plays a causal role in phenotypic variation. Ruminococcaceae&#95;UCG-013 was more abundant in the gut microbes of mice with a lean phenotype than in those with an obese phenotype. Ruminococcaceae&#95;UCG-013 was identified as the most significant biomarker for alleviating obesity by random forest analysis. In a correlation analysis of serum parameters and body weight, Ruminococcaceae&#95;UCG-013 was positively associated with serum HDL-C levels and negatively associated with serum TC, TG, and LDL-C levels. To conclude, Ruminococcaceae&#95;UCG-013 was identified as a novel microbiome biomarker for obesity resistance, which may serve as a basis for understanding the critical gut microbes responsible for obesity resistance. Ruminococcaceae&#95;UCG-013 may serve as a target for microbiome-based diagnoses and treatments in the future.

Straw mulching and N fertilization are effective in augmenting crop yields. Since their combined effects on wheat rhizosphere bacterial communities remain largely unknown, our aim was to assess how the bacterial communities respond to these agricultural measures. We studied wheat rhizosphere microbiomes in a split-plot design experiment with maize straw mulching (0 and 8,000 kg straw ha -1 ) as the main-plot treatment and N fertilization (0, 120 and 180 kg N ha -1 ) as the sub-plot treatment. Bacterial communities in the rhizosphere were analyzed using 16S rRNA gene amplicon sequencing and quantitative PCR. Most of the differences in soil physicochemical properties and rhizosphere bacterial communities were detected between the straw mulching (SM) and no straw mulching (NSM) treatments. The contents of soil organic C (SOC), total N (TN), NH 4 + -N, available N (AN), available P (AP) and available K (AK) were higher with than without mulching. Straw mulching led to greater abundance, diversity and richness of the rhizosphere bacterial communities. The differences in bacterial community composition were related to differences in soil temperature and SOC, AP and AK contents. Straw mulching altered the soil physiochemical properties, leading to greater bacterial diversity and richness of the rhizosphere bacterial communities, likely mostly due to the increase in SOC content that provided an effective C source for the bacteria. The relative abundance of Proteobacteria was high in all treatments and most of the differentially abundant OTUs were proteobacterial. Multiple OTUs assigned to Acidobacteria, Chloroflexi and Actinobacteria were enriched in the SM treatment. Putative plant growth promoters were enriched both in the SM and NSM treatments. These findings indicate potential strategies for the agricultural management of soil microbiomes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Chen, Xiang, Ma, Penttinen, Zheng, Huang and Fan.)

The parameter-tuning stochastic resonance (SR) method can convert part of the noise energy into the signal energy to suppress the noise and amplify the signal, comparing with traditional weak periodic signal detection methods (e.g., time average method, filtering method, and correlation analysis method). In this work, the numerical calculation is conducted to find the optimal resonance parameters for applying the SR method to the wavelength modulation spectroscopy (WMS). Under the stochastic resonance state, the peak value of 2f signal (a constant concentration of CH 4 ∼20 ppm) is effectively amplified to ∼0.0863 V, which is 3.8 times as much as the peak value of 4000-time average signal (∼0.0231 V). Although the standard deviation also increases from ∼0.0015 V(1σ) to ∼0.003 V(1σ), the SNR can be improved by 1.83 times (from ∼25.9 to ∼15.8) correspondingly. A linear spectral response of SR 2f signal peak value to raw 2f signal peak value is obtained. It suggests that the SR method is effective for enhancing photoelectric signal under strong noise background.

Methionine is one of the many amino acids in the soil. In order to study the role of methionine in acidic forest soil, the effect of methionine (Met) was compared with control together with addition of ammonium (Met + A), nitrite (Met + N), and glucose (Met + C) under 60% or 90% water holding capacity (WHC), because ammonium and nitrite are important factors in nitrification, and glucose affect the heterotrophic nitrification and nitrogen immobilization. We found that methionine addition significantly reduced NO 3 - concentration in acidic forest soil. Compared to Met, Met + A and Met + N treatments non-significantly enhanced nitrification; however, Met + C treatment decreased NH 4 + concentration which suggested that soil autotrophic and heterotrophic nitrification were limited in the presence of methionine at 60% WHC. Further, our findings of 15 N-labeled treatment showed the impact and priming effect of methionine was negative for NO 3 - concentration and positive for N 2 O emission, which were observed mainly from the soil N source rather than methionine. At 90% WHC, Met + C treatment significantly lessened concentrations of NH 4 + and NO 3 - , nonetheless improved N 2 O compared to Met treatment. Therefore, besides the denitrification and dissimilatory NO 3 - reduction to ammonia, the immobilization might be the key factor to explain this decrease in NO 3 - concentration at 90% WHC, while these processes were induced with the C addition. This study indicated that the positive role of amino acids in soil N cycling might be overrated.

This paper is in response to the article entitled "Open educational resources and college textbook choices: a review of research on efficacy and perceptions" (Hilton, 2016). In the article, Hilton synthesized the results of 16 studies, and proposed a statement that the decision to employ and adopt open textbooks in higher education has appeared to have financial benefits to students without decrease in their learning outcomes. This finding would strengthen credibility of open textbooks use and encourage faculty to utilize high-quality open textbooks in a post-pandemic world. However, only if teachers are willing to develop and use open textbooks can millions be saved for students and higher performance be achieved by students. Furthermore, from integrative model of behavior prediction, future research needs to probe a variety of issues relating to how teachers could be intentionally and effectively use open textbooks to empower the digital learning in the 21st century., Competing Interests: Conflict of interestAll authors declare that they have no conflict if interest., (© Association for Educational Communications and Technology 2021.)

Nitrogen (N) cycle in forest soils is altered by water, salt, or acid solutions, and its internal transfers to and from each existing inorganic pools are not known comprehensively. To evaluate the soluble and exchangeable N pools, bulk soil (B soil), water-extracted soil (W soil), and the 0.5 mol L -1 K 2 SO 4 -treated soil (K soil) were incubated for up to 48 days to comprehend the dynamics of inorganic (NH 4 + and NO 3 - ) and soluble organic N (SON) in water-soluble, exchangeable, 2.5 mol L -1 H 2 SO 4 (labile pool I, LPI) and 13 mol L -1 H 2 SO 4 (labile pool II, LPII) pools. To test the N deposition effects, additional NH 4 NO 3 solution was added to B, W, and K soils at amount of 40 mg N kg -1 soil. The results showed that though there was more NO 3 - removed when W soil was prepared, the similar net nitrification rate in W soil to B soil and more than 20 mg N kg -1 water-soluble NO 3 - were observed in W soil, which indicated that the loss of NO 3 - would be enhanced. In contrast, there was more water-soluble and exchangeable NH 4 + for K soil compared with B soil. The different dynamic of NO 3 - between W and K soil suggested that nitrifiers might dominate in the soil matrix rather than the soil solution. After incubation, each N form in the LPI decreased, which can be attributed to the allocation of remaining N into the recalcitrant pool, except the increase of NH 4 + for B soil and NO 3 - for K soil, and NO 3 - in LPII for B soil. Compared with control, N addition increased mineralization of exchangeable SON to promote nitrification regardless of soils, but weakened the immobilization of NO 3 - . In addition, N in LPI and LPII pools have increased, which might be related to decomposition of recalcitrant organic matter induced by N addition to transform when the water-soluble and exchangeable N was removed. Therefore, the changes of soluble and exchangeable nitrogen pools impact the N cycling. Our findings can give some explanation for whole soil N transformation responses to N deposition.

Amino sugars (AS) are routinely used as microbial biomarkers to investigate the dynamics of soil carbon (C) and nitrogen (N) under different environments. However, the effect of any AS on soil C and N, or other AS, is not well-defined. In this study, acid soils from Dongbei (D) and Fujian (F) and alkaline soil from Henan (H) were selected to perform an incubation experiment under glucosamine addition for 36 days. In the present study, the dynamics of soil soluble organic C (SOC), NH 4 + -N, NO 3 - -N, soluble organic N (SON), and four AS: glucosamine (GluN), mannosamine (ManN), galactosamine (GalN), and muramic acid (MurN), were investigated. The results showed that AS was different among the three soils, but had similar dynamics in the same soil. The higher total C and inorganic N in the D and F relative to the H soil were related to the greater AS in two soils. With incubation, AS decreased in D soil and increased in F soil before 1 week, while after 1 week, the inverse dynamics were observed, which suggest that SOC or SOC combined with inorganic N may be a mechanism to adjust the dynamics of C from AS. Overall, glucosamine addition did not significantly affect AS in D, while the reverse was true for F and H soils. Glucosamine addition decreased AS at day 0 for D soil and at day 3 for F and H soils, and increased SOC. The lowered NH 4 + -N and AS in D soil, but the higher values of these, were observed in F soil after 1 week of incubation. The increase of SON in D soil with glucosamine addition might be due to the depolymerization of soil organic matter (SOM) into SON. However, the decrease of SON in F soil could be attributed to the mineralization of SON.

Background: Myocardial infarction (MI) is partly due to myocardial cell damage caused by hypoxia. MicroRNAs (miRNAs) have been proved to be closely related to the development and progression of many cardiovascular diseases. This study investigated the role of miR-145 in cardiomyocytes under hypoxic condition., Methods: The quantitative real-time polymerase chain reaction (qRT-PCR) was performed to test miR-145 expression in H9c2 cells with hypoxia-inducible factor (HIF)-a abnormal expression under hypoxic condition. The 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyltetrazolium bromide (MTT), Tran-swell assay and flow cytometry were used to investigate the effects of miR-145 on cell viability, migration and apoptosis under normoxic or hypoxic condition, respectively. Meanwhile, reactive oxygen species (ROS) content in hypoxic H9c2 cells was analyzed. Western blotting was used to explore the potential mechanism of miR-145 protective effects on cardiomyocytes. Expression levels of miR-145 and SGK1 in rat MI model were also assessed., Results: Results showed that miR-145 was upregulated in H9c2 and HL-1 cells under hypoxic condi-tion, which was promoted by HIF-1a. MiR-145 overexpression enhanced cell viability and migration under normoxic condition. Under hypoxic condition, miR-145 overexpression promoted cell viability, inhibited apoptosis and ROS activity. Western blotting results proved that miR-145 overexpression inhibited the activation of apoptotic related factors, and promoted activation of PI3K/AKT signaling pathway via SGK1 upregulation. Expression levels of miR-145 and SGK1 were both upregulated in rat MI models., Conclusions: HIF-1a could induce miR-145 upregulation in hypoxic H9c2 and HL-1 cells. MiR-145 protected H9c2 cells against hypoxic damage. SGK1 upregulation and activated PI3K/AKT may have participated in the protective effects of miR-145 on cardiomyocytes.

Objective: To explore the effects of varus of knee osteoarthritis (OA) on patellar position., Methods: A total of 19 patients (27 knees) underwent the examinations of anterior-posterior, lateral knee and axis of patellar X-ray at 30°, 45°, 60° and each X-ray was measured., Results: The ratio between length of patellar tendon and length of patellar, vertical distance of lower edge of patellar to tibial plateau and height of patellar, distance of lower edge of medial facet of patellar to anterior angle of tibia and height of patellar were different from normal values. Patellar moved medially during the process of bending from 30°to 60°., Conclusion: The patellar of knee OA patients with varus moves down and medially.

Objective: Current study was conducted to investigate the seed physiological characteristics of Tulipa edulis and improve germination rate., Method: Anatomical characteristics was observed. Seed water absorption curve was tested by soaking method. Dynamic of embryo development and germination rate as well as germination index under different conditions were recorded. And the biological test of cabbage seed was used for detecting the germination inhibitors., Result: The embryo rate of newly matured seeds was about 10%, and there was no obstacle of water absorption on testa of T. edulis. The optimum method for embryo development was exposure to 300 mg x L(-1) gibberellin solution for 24 hours, and stratification at 25 degrees C for 70 days followed by stratification at 5 degrees C for 40 days. The germintion rate and germination index of dormancy-broken seeds under the dark environment at 10 degrees C and 15 degrees C were significantly higher than those under other conditions. Additionally, there were some germination inhibitory substances in dry seeds., Conclusion: The seed of T. edulis can be classified as having complex morphophysiological dormancy, and the morphological embryo dormancy played a leading role. Warm and cold stratification resulted in a fast dormancy breaking effect, and a high germination rate more than 90% could be obtained under the optimum conditions.

Objective: Current study on the pollination biology of Tulipa edulis was conducted to investigate its pollination characteristics and to provide references for artificial domestication and breeding of T. edulis., Method: Flowering dynamics, pollinators, morphology and structure of flower were observed. Different methods were adopted to evaluate the pollen vitality, and benzidine-H2O2 method was used for estimation of the stigma receptivity. Breeding system was evaluated based on out-crossing index (OCI) , pollen-ovule ratio (P/O) and the results of emasculation, bagging and artificial pollination studies., Result: The flower of T. edulis showed typical characteristics of Liliaceae. The pollen remained viable to some extent during all the anthesis and peaked within three days after blossoming. Stigma acceptability peaked in the first day of blossom and dwindled away in the next four days. The type of breeding system of T. edulis was facultative xenogamy, three species of Halictus are the main pollination insects., Conclusion: The type of breeding system of T. edulis was facultative xenogamy, withal cross-pollination give priority to self-pollination, and the insects play a main role on the pollination of T. edulis, further validation are needed to judge if the wind is helpful to pollination.

Objective: Present study was conducted to explore the growth and photosynthetic characteristics of Tulipa edulis under different light conditions (23%, 45%, 63%, 78%, 100% of full sunlight) and to determine the optimum light intensity for growth of T. edulis., Method: The leaf area and biomass indicators as well as reproductive characteristics were measured. The photosynthetic basic parameters and light response curve were determined by a LI-6400XT portable photosynthesis system, and the light response curve characteristic parameters was determined. Additionally, chlorophyll fluorescence parameters were determined by assorted fluorescence leaf chamber of LI-6400XT., Result: The lowest biomass yield was observed in the 23% and 100% of full sunlight treatments while the highest value was found under the 78% of full sunlight conditions. With the reduction of light availability, the success rate of sexual reproduction, light saturation point (LSP) and light compensation point (LCP) reduced, while apparent quantum yield (AQY) increased. 23% and 45% of full sunlight treatments led to lower photosynthesis rate (Pn) and higher apparent quantum yield (AQY) in comparison with other treatents. The highest photosynthesis rate was observed in the 78% and 100% of full sunlight treatments. In addition, 78% of full sunlight treatments led to highest Fv/Fm, Fv'/Fm', PhiPS II, ETR, and qP., Conclusion: T. edulis was able to adapt in a wide range of light intensity, and 78% of full sunlinght was the most suitable light condition for growth of T. edulis.

The growth and competition of a C3 crop rice and a C4 weed, barnyardgrass under FACE(free-air carbon dioxide enrichment) conditions were studied by field experiment. The results showed that under FACE condition, the biomass and yield, leaf number, tiller number, and leaf area index of rice increased, while those of barnyardgrass decreased. Both of the leaf area indexed of rice and barnyardgrass were decreased, while their net assimilation rate increased. When the ratio of planting density of rice and barnyardgrass was 1:1, all of the ratio of biomass, yield, leaf area index, tiller and net assimilation rate were increased under FACE condition. It indicated that the competition between rice and barnyardgrass changed under FACE condition. The competition ability of rice(C3 crop) was enhanced relatively, while that of barnyardgrass weakened.

FACE (Free-air Carbon Dioxide Enrichment) was used to study the effects of elevated CO2 on rice (Oryza sativa) growth, tissue C/N, N and P concentration and uptake at different development stages under two N and two P levels. Results showed that elevated CO2 increased dry matter accumulation in rice stem, ear and root. Leaf dry matter was increased at tillering stage and no significant effect was found at jointing, heading and ripening stages. N concentration of stem and leaf was decreased. Ear N concentration at heading stage was increased but was decreased at ripening stage. No significant effect was found on root N concentration at tillering stage but root N concentration at jointing, heading and ripening was decreased. Leaf P concentration at jointing, heading and ripening was increased but no significant effect was found on P concentration in stem, ear and root. C content in various tissues changed unremarkably and the ratio of C over N (C/N) was increased. Elevated CO2 significantly increased P uptake in aboveground tissues; and increased N uptake, but the difference was not statistically significant. N and P fertilization had no significant effect on various tissue dry biomass. Tissue N content at higher N fertilization was higher than at lower N fertilization but no such effect of P fertilization on tissue P content was found. At higher N fertilization, elevated CO2 increased the ratio of below-ground biomass over above-ground biomass at ripening stage. Possible reasons are discussed for the differences of tissue N and P content and the ratio of below-ground biomass over above-ground biomass between elevated and ambient atmospheric CO2 concentrations.