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This work investigates the problem of future linear equation system under various noises. Firstly, a continuous advanced zeroing neurodynamic (CAZN) model under noise is developed to solve continuous linear equation system. Subsequently, by combining a general explicit linear left–right four-step (ELLRFS) formula with the CAZN model, a general ELLRFS discrete advanced zeroing neurodynamic (ELLRFS-DAZN) algorithm under noise is proposed to solve the future linear equation system. Theoretical analyses and results manifest the convergence performance of the general ELLRFS-DAZN algorithm under various noises. Moreover, numerical experimental results, including those based on a UR5 manipulator, validate the effectiveness and robustness of the general ELLRFS-DAZN algorithm under various noises. Numerical experimental results based on mobile acoustic source localization further substantiate the superiority of the general ELLRFS-DAZN algorithm under constant noise. Finally, physical experimental results based on a Kinova JACO2 manipulator substantiate the practicability of the general ELLRFS-DAZN algorithm under bounded random noise. [ABSTRACT FROM AUTHOR]

The strength and hardening of metallic materials are dictated by the motion and interactions of dislocations. Individual dislocations intersect, react, and frequently form junctions, defining a defect topology that is the basis of subsequent deformation. While immobilized dislocation locks are intuitively considered as potent strengthening structures, simulations suggest that glissile reactions are a predominant contributor to hardening among the four types of dislocation reactions in face-centered cubic crystals, even though the resulting dislocations are inherently mobile. To date, the prevailing understanding of glissile reactions has been primarily based on classical geometric models of perfect dislocations and simulations thereof. Understandings of the reaction pathways and detailed experimental characterization of glissile reactions are lacking, leaving the potential topological variations shrouded in mystery. This study details molecular dynamics simulations of glissile reaction involving dissociated partial dislocations, and the direct experimental characterization of the dislocation configurations resulting from glissile reactions in deformed pure aluminum using transmission electron microscopy. The experimentally-determined structure was reconstructed in 3D and parametrically studied in discrete dislocation dynamics simulations, revealing varying topological evolutions under different loading conditions. Further statistical analyses on an ensemble of simulated dislocations revealed the essential role of stress states and cross-slip in affecting the probability of glissile reaction and the fraction of mobile dislocation nodes. These findings point to avenues for the development of dislocation-based constitutive theories of plasticity. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, discrete-time nonlinear optimization (DTNO) for tracking control of robot manipulators is investigated. By utilizing zeroing neural dynamics (ZND) method, a continuous-time ZND (CTZND) model is first proposed for solving the corresponding continuous-time nonlinear optimization (CTNO) problem. Afterwards, three different explicit linear multi-step methods (i.e., explicit linear 3-step, 2-step, and 1-step methods) are respectively presented and investigated. To solve such a DTNO problem, the explicit linear 3-step method is adopted to combine with the CTZND model, and hence a 3-step discrete-time ZND (DTZND) model is proposed. For comparison purposes, 2-step and 1-step DTZND models are also developed. Besides, theoretical analyses indicate the validity and superiority of the proposed 3-step DTZND model. Finally, the numerical experimental results based on a 2-joint robot manipulator and a PUMA560 robot manipulator further verify that the proposed 3-step DTZND model is much superior to the other two DTZND models. [ABSTRACT FROM AUTHOR]

Multiferroic oxide YCrO 3 has attracted much interest in recent years due to its potential application as multifunctional materials. In present study, its structural stability and phonon modes have been investigated by Raman spectroscopy at temperatures from 100 to 600 K and under pressures up to 35.5 GPa. The successive evolution of Raman spectra indicates a good stability of this compound at high pressure and this temperature range. Thermodynamic Grüneisen parameters and intrinsic anharmonic parameters are calculated for each Raman active mode. The description of the line-broadening and the line-shift of the observed Raman lines are mainly based on the anharmonicity due to the phonon–phonon interaction, which are useful in modeling of thermodynamic entities. • Structure stability of YCrO 3 is studied using Raman spectroscopy from 100 to 600 K and under pressures up to 35.5 GPa. • Thermodynamic Grüneisen parameters and intrinsic anharmonic parameters are derived from Raman spectra. • Implicit and explicit anharmonicity, as well as the contribution of three- and four-phonon processes are separated. [ABSTRACT FROM AUTHOR]

• A spin glass freezing peak was observed in Ca 3 CoMnO 6 around T f = 172 K. • The results suggest the co-existence of competing short range AFM and FM order. • The short-range spin order can be suppressed effectively by external field. • Due to the competing AFM and FM interaction, exchange bias effect was observed. Rhombohedral structural Ca 3 CoMnO 6 was prepared. The microstructure, chemical composition, morphology were checked and the magnetic properties were investigated in detail. Due to the "order-by-disorder" phenomenon, the ZFC curve presents negative susceptibility in low temperature region. Besides the antiferromagnetic transition around T N = 13.5 K, another abnormal peak around T f = 172 K was also observed. The shift of the abnormal peak towards low temperature with the field increases, magnetic relaxation experiment and the training effect confirm the freezing spin glass characteristic. The broadening of the freezing peak in higher field can be well explained by the reduction of short-range magnetic correlation length. Due to the competing antiferromagnetic and ferromagnetic interactions, obvious exchange bias effect was observed. [ABSTRACT FROM AUTHOR]

With the increasing demand for the application of multiple quadrotors, improving their autonomous flight ability in unknown environments has become one of the research focuses in the robot field. In this paper, a distributed obstacle avoidance controller is proposed with three elaborate control terms: obstacle avoidance term, inter-robot collision avoidance term, and formation reconstruction. Firstly, an online local obstacle avoidance algorithm is designed based on the obstacle avoidance behavior of the pigeon flock and potential field theory. Then, inspired by the spring-damped system, an inter-robot collision avoidance algorithm is designed based on Hooke's law with damping. Furthermore, based on the consensus theory and local neighboring information, a distributed formation reconstruction controller is designed. Finally, the simulation and quantitative analysis are carried out in Gazebo simulation platform. For practical application, an outdoor experimental platform with six quadrotors is constructed to verify the practicability of the proposed method. The results show that the three control terms are compatible with each other to achieve obstacle avoidance and can achieve formation control for quadrotors. [ABSTRACT FROM AUTHOR]

C-reactive protein (CRP) is a widely accepted biomarker of cardiovascular disease and inflammation. In this study, a RNA aptamer-based electrochemical sandwich type aptasensor for CRP detection was described using the functionalized silica microspheres as immunoprobes. Silica microspheres (Si MSs), which have good monodispersity and uniform shape, were firstly synthesized. The silica microspheres functionlized with gold nanoparticles (Au NPs) provided large surface area for immobilizing signal molecules (Zinc ions, Zn 2+ ) and antibodies (Ab). RNA aptamers, which were specific recognized to CRP, were assembled on the surface of Au NPs modified electrode via gold-sulfur affinity. In the presence of CRP, a sandwich structure of aptamer-CRP-immunoprobe was formed. Square wave voltammetry (SWV) was employed to record the sensing signal, and a clearly reductive peak corresponding to Zn 2+ at about −1.16 V (vs. SCE) was obtained. Under optimal conditions, the aptasensor showed wide linear range (0.005 ng mL −1 to 125 ng mL −1 ) and low detection limit (0.0017 ng mL −1 at a signal-to-noise ratio of 3). Some possible interfering substance was also investigated, and the results obtained showed that the aptasensor possessed good selectivity. When the aptasensor was applied to real serum samples analysis, the satisfied results were obtained, indicating that the aptasensor possessed potential real application ability. [ABSTRACT FROM AUTHOR]

In this study, we tried coupling the small signal molecules that could intercalate into DNA double helix with hybridization chain reaction (HCR) technique to fabricate a multiple immunosensor. Doxorubicin hydrochloride (DXH) and methylene blue (MB) were used as signal molecules and alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) were selected as model biomarkers. The immunosensor mainly consists of three parts as follows: First, two different primary antibodies (Ab 1 ) immobilized on the surface of gold nanoparticles (Au NPs); Second, secondary antibodies (Ab 2 ) conjugated with DNA primer; Third, long DNA concatemers from HCR were used as a carrier to intercalate amounts of signal molecules (DXH or MB). A sandwich immunocomplex was formed among primary antibodies, target biomarkers and secondary antibodies conjugated with DNA primer via specific recognition reaction. Afterwards, DNA concatemers intercalating amounts of DXH or MB were linked to DNA primer via DNA hybridization. Square wave voltammetry (SWV) was employed to record the response signals from electroactive molecules DXH and MB, and two distinguishable signals were obtained, which peak potentials were at about −0.30 V (corresponding to MB) and −0.70 V (corresponding to DXH, both vs SCE), respectively. The signal intensities of MB and DXH were linearly related to the logarithm of biomarkers concentration in the range of 0.05 pg mL −1 –25 ng mL −1 , and the limit of detection were 0.03 pg mL −1 for CEA and 0.02 pg mL −1 for AFP (at S/N=3), respectively. Furthermore, the immunosensor exhibited a sensitive electrochemical response to biomarkers in human serum samples and the results obtained were in accordance with reference method, indicating the immunosensor can be applied to real sample analysis in clinic diagnosis. [ABSTRACT FROM AUTHOR]

Multiple quadrotors are becoming increasingly attractive in many fields, and the formation tracking control of multiple quadrotors is the foundation for performing complex tasks. In this paper, the collision-free formation tracking control problem for multiple quadrotors under switching topology is studied, and the leader has the control command, which is unknown to the followers. A formation tracking control protocol is firstly constructed utilizing local neighboring information, in which the neighbors of the quadrotors can change. Then, inspired by the spring-damping system, a collision avoidance mechanism based on Hooke's law with damping is proposed to avoid collision of multiple quadrotors in a cluttered flight. By using the Lyapunov based stability analysis, it is proved that multiple quadrotors can track the dynamic leader in a dynamic formation using the proposed protocol under formation feasibility and the existence of spanning trees in communication topology. Finally, a lightweight communication protocol is designed in the experimental platform. Several groups of visual simulations are carried out based on the Gazebo simulator. The proposed method is compared with two potential field methods in two scenarios through quantitative studies of task efficiency and error analysis. Overall, the completion time is improved by 86.02% and 31.98%, and the minimum tracking error is improved by 57.24% and 46.20% in scenario 1. The completion time is improved by 86.88% and 30.34%, and the minimum tracking errors are improved by 82.20% and 42.62% in scenario 2. Outdoor experiments on formation tracking are performed to verify the effectiveness of the proposed methods. Furthermore, several outdoor experiments are conducted in the same scenarios to validate the proposed algorithm. [ABSTRACT FROM AUTHOR]

• The k d and τ c decreased with straw incorporation time prolonged. • The straw amount was the key factor influencing rill erosion resistance. • The k d and τ c could be linearly fitted by soil aggregate greater than 0.25 mm. The widely implemented wheat straw incorporation returning combined with nitrogen fertilizer and newly-developed secondary plant metabolites such as polyphenol, could result in variations of rill erosion resistance, and then soil detachment and channel scour. However, the variation pattern and its key influencing factorsremain unclear. Taking a silt loam soil as the research object, this study used the orthogonal table of L 9 (34) to arrange four influencing factors at three levels: straw length (2, 5, 8 cm), straw returning amount (2000, 4000, 8000 kg h m−2), nitrogen amount (100, 140, 180 kg hm−2), and polyphenol amount (0, 40, 80 kg hm−2). Rill erodibility (k d) and soil critical shear stress (τ c), representing the soil resistance to rill erosion, were measured twice by submerged jet equipment in August 2020 and 2021. The results presented significant temporal variations in k d and τ c with changes in straw decomposition and soil properties after straw incorporation. Compared with the results on day 60 following straw incorporation, k d and τ c decreased by 57.07% and 25.11% on day 425, respectively. On day 425, the straw length, straw returning amount, and nitrogen amount had significant effects on k d (P < 0.05), with the contributions of 7.97%, 42.06%, and 7.62%. Conversely, the straw returning amount and polyphenol amount had significant effects on τ c , with respective contributions of 50.88% and 11.24%. The variation of k d and τ c could be linearly fitted by the soil aggregate greater than 0.25 mm, with R2 values of 0.71 and 0.87, respectively, which could be used to estimate rill channel scour depth in the Soil and Water Assessment Tool in the absence of measured data on soil resistance to rill erosion. [ABSTRACT FROM AUTHOR]

The development of genetic and genomic resources for biological studies in cucumber has experienced an unprecedented boom in recent years. To investigate the function of putative meiotic genes and germplasm in breeding programs, an accurate cytogenetic characterization is required. Cytological methods and reference to investigate meiosis in cucumber are limited at present. Here we provide a set of cytological techniques that have been adapted for the study of meiosis in cucumber. The meiotic stages can be identified with high precision using hierarchical criteria from developing buds, undisturbed meiocytes, and freshly stained chromosomes. A meiotic cytological atlas of all stages is presented as a reference for identifying particular stages and for comparison of meiosis between normal and mutant plants. We performed a comparative analysis of the distribution of cytoplasmic organelles between cucumber and Arabidopsis, and we described a highly nonsynchronous condensation of chromosome parts during diplotene. A simplified fluorescence in situ hybridization (FISH) protocol, using robustly spread chromosomes, were developed. In addition, we designed a single oligonucleotide probe for 5S rDNA to use in karyotyping and monitoring of homologous chromosome pairing, which will make FISH analysis of 5S rDNA easier and more economical. • Techniques for meiosis staging, chromosome preparation and FISH in cucumber. • A cytological atlas of cucumber meiosis is provided for reference. • A non-synchronous chromosome parts during diplotene is described. • We designed a single oligonucleotide probe for 5S rDNA to monitor homologous pairing. [ABSTRACT FROM AUTHOR]

The effects of water deficit on maize growth and physiological activities have been extensively studied. However, there are few studies about how various nitrogen (N) fertilizer types alleviate the impact of water stress on maize yield. A two-year field experiment was conducted to explore the effects of N type on maize growth, physiological characteristics and gain yield under various water-stressed conditions in 2019 and 2020. This experiment included three irrigation levels of W1 (60% ET c , ET c is crop evapotranspiration), W2 (80% ET c) and W3 (100% ET c), and three N fertilizer types of urea (U), slow-release nitrogen fertilizer (SRF) and blending U and SRF (UNS). The results showed that W1 and W2 significantly reduced maize leaf area index and leaf N content, which declined maize net photosynthetic rate (P n), transpiration rate (T r) and chlorophyll fluorescence, inhibited chlorophyll synthesis and thus reduced maize yield. W3 not only increased maize growth, P n and T r , but also enhanced the correlation between P n , chlorophyll content, chlorophyll fluorescence parameters and leaf area index/leaf N content. The application of UNS alleviated the grain yield reduction associated with water stress. Under W1 (W2), the grain yield in UNS were 3.6–22.1% (10.4–25.0%) and 4.4–24.2% (5.3–15.4%) greater than that in U and SRF, respectively. Although W3SRF obtained the highest yield grain among all the treatments, no significant difference was found between W3UNS and W3SRF. Under the same irrigation amount, UNS increased the water productivity compared with U. In conclusion, UNS could stabilize grain yield by regulating maize leaf functional traits to cope with future climate change and ensure regional food security. • LAI and leaf N content can evaluate the response of leaf development process to water deficit. • W3 increased the correlation coefficients between leaf function index and LAI/leaf N content. • UNS alleviated the negative effects of water deficit on leaf functional index of maize. • UNS could stabilize grain yield by regulating maize leaf functional traits. [ABSTRACT FROM AUTHOR]

Agricultural production is facing the risk of severe water shortage, serious non-point source pollution and low water productivity (WP) and nitrogen use efficiency (NUE). It is a major challenge to achieve environmentally friendly production of maize with high WP and NUE. A two-year field experiment with three irrigation levels of W1 (60% ET c , ET c is the crop evapotranspiration), W2 (80% ET c) and W3 (100% ET c), and three nitrogen (N) fertilizer types of urea (U), slow-release N fertilizer (SRF) and urea blended with slow-release N fertilizer (UNS) was conducted in 2019 and 2020, so as to quantify their impacts on the maize dry matter, N uptake and remobilization, grain yield, WP, NUE and residual soil NO 3 −-N. The results showed that W2 and W3 significantly increased total dry matter (8.0% and 14.7%), grain yield (19.4% and 33.0%), and NUE (1.5% and 2.2%) compared with W1. Total N uptake of maize declined by 23.2% and 9.6% under W1 and W2, leading to 11.9% and 5.8% increased of soil NO 3 −-N, respectively. Compared with U, UNS increased post-silking N uptake by 19.1%, thereby enhancing grain yield by 18.3%. Compared with SRF, UNS increased N remobilization from vegetative organs to grains by 15.0%, thereby resulting in 2.3% increase in grain yield. Under the same irrigation amount, UNS and SRF improved WP and NUE compared with U. W3SRF obtained the highest grain yield, with increases in grain yield by 2.4–58.8% compared with other treatments, while there was no significant difference between W3SRF and W3UNS. More importantly, UNS significantly increased grain yield and alleviated the impact of water stress on maize production under W1 and W2. In conclusion, UNS could stabilize grain yield under water-stressed conditions, while SRF could increase grain yield under full irrigation. • W3 (100% ET c) increased maize N uptake and significantly reduced residual soil NO 3 −-N. • UNS increased post-silking N uptake by 19.1%, resulting in 18.3% increases of grain yield. • UNS enhanced N remobilization of vegetative organs by 15.0% and thus grain yield by 2.3%. • UNS can alleviate the pressure of maize yield reduction caused by water deficit through adjust N supply. [ABSTRACT FROM AUTHOR]

We combined the unique natural oxygen transporting function of red blood cells (RBCs) with photosensitive nanocomposites to create biomaterials with strong singlet oxygen (1O 2) generation. During cold storage for a long time, structural changes to RBCs may occur, which reduce their oxygen carrying capacity. The nanocomposite developed herein featured dual emission characteristic, which enabled evaluation of the status of the RBCs. On the basis of energy transfer from the conjugated polymer to iridium(III) complexes, the formed nanocomposites show intense, long-lived and oxygen-sensitive emission. When modified with 1,2-distearoyl- sn -glycero-3-phosphoethanolamine- N -[methoxy(polyethyleneglycol)-2000], the nanocomposites non-invasively entered RBCs through hydrophobic interactions. We measured the quenching effect of oxygen on the emission of the iridium(III) complexes. The differential fluorescent signals and fluorescence lifetime images indicated the storage history of the RBCs. RBCs in good condition stored oxygen. When engineered with nanocomposites, RBCs generated large amounts of cytotoxic 1O 2 upon irradiation. These decorated RBCs might serve as a new kind of photosensitive biomaterial. Image 1 • The nanocomposites show intense dual-emission based on efficient energy transfer. • The nanocomposites possess oxygen-sensitive luminescence properties. • The oxygen-carrying ability of stored RBCs can be analyzed by the nanocomposites. • The oxygen supply in modified RBCs generated vast cytotoxic 1O 2 upon irradiation. [ABSTRACT FROM AUTHOR]

In this paper, the crystal structure, vacancy defect, local electron density and magnetic properties of Gd 1- x Ca x CrO 3 (0 ≤ x ≤ 0.3) polycrystalline samples were investigated systematically. The crystal structural analyses show that all the samples are orthorhombic phase and a structural distortion happens around x = 0.3. Due to the formation of Cr4+ ions, both the lattice constant and the Cr–O bond length decrease. The results of positron annihilation spectrum reveals that the vacancy defect concentration increases and the local electron structure changes with the introduction of Ca2+ ions. The field-cooled (FC) and zero-field cooled (ZFC) curves of Gd 1- x Ca x CrO 3 samples measured under H = 100 Oe exhibits negative magnetization characteristics due to the interaction between Gd3+ and Cr3+ ions, and the magnetism can be affected by the structural distortion. [ABSTRACT FROM AUTHOR]

Optimising the management of water and fertilizer, and fully exploiting the positive effects of the coupling of water and fertilizer, are important ways of achieving high crop yields and promoting the sustainable development of water-efficient agriculture. The objective of this study was to investigate the coupling effects of different irrigation levels and different mixing ratios of slow-release nitrogen fertilizers on the physiological growth characteristics and yield of winter wheat in Guanzhong region under drip irrigation. In this study, field experiments were conducted in two winter wheat growing seasons, 2018–2019 and 2019–2020. The study included three irrigation levels: W1 (60% ETc, where ETc is the evapotranspiration of the crop), W2 (80% ETc), and W3 (100% ETc); and four N fertilizer treatments: U (100% urea), UNS1 (urea: slow-release N fertilizer = 1:1), UNS2 (urea: slow-release N fertilizer = 1:3) and SRF (100% slow-release N fertilizer). Compared to W1 and W2, W3 prolonged the winter wheat leaf functional period, increased leaf area index and net photosynthetic rate (P n), and promoted dry matter accumulation. The total N content of winter wheat decreased by 22.67% and 9.93% under W1 and W2 conditions, respectively. The nitrogen use efficiency (NUE) decreased by 5.87% and 1.97%, respectively, leading to a decrease in yield. Slow-release nitrogen fertilizer (SRF) and its mixture treatments (UNS1, UNS2) increased post-flowering nitrogen uptake in winter wheat compared to U. At the same irrigation level, water use efficiency (WUE) was increased by 34.03%, 13.35%, and 20.86% in the UNS2 treatment compared to U, UNS1, and SRF, respectively. W3UNS2 obtained the highest grain yield: 8026.32 kg hm−2 (2018–2019) and 8993.25 (2019–2020) kg hm−2, with a 9.85–68.24% yield increase compared to other treatments. Und4er the treatments of this study, yield, WUE, and NUE of winter wheat reached 90% of the maximum at irrigation levels of 82.04–91.83% ETc and 59.18–83.67% of slow-release N fertilizer in blended fertilizer. Under water stress conditions, UNS1 and UNS2 can mitigate the effects of water deficit on plant growth and stabilize grain yield. This study provides useful information for optimising water and nitrogen management decisions for winter wheat in semi-arid climatic regions, and contributes to the promotion of sustainable development of wheat production and water-efficient agriculture. • The two-year drip trial was conducted in a sheltered canopy in GuanZhong. • Field trial address in the coupling impacts of irrigation&fertilizer on winter wheat. • Recommended irrigation volumes and mixing ratios were obtained using modelling. • Blended slow-release nitrogen fertilizer can effectively mitigate the drought effects. • 100% ETc with U:SRF = 1:3 is the most recommended irrigation and fertilization option. [ABSTRACT FROM AUTHOR]

In this work, Ga3+ doped YCr 1- x Ga x O 3 (x = 0, 0.1, 0.2 and 0.3) polycrystalline samples were prepared by solid state reaction method and their crystal structure, morphology, internal defect, specific heat and magnetic properties were studied. The results show that the lattice constants, lattice volume and particle size increase, while Y/Cr–O bond constant decreases with replacing Cr3+ by Ga3+. The positron annihilation spectrum (PAS) measurement shows that cation vacancy defect exists in all samples and the internal defect concentration fluctuates slightly with increasing of Ga3+ ions doping concentration. For low doping content, an additional magnetization anomaly emerges in the zero-field-cooling curves measured in H = 1000Oe. With the increase of magnetic field, the anomaly can be well suppressed. Simultaneously, for the specific heat curve peak cannot be observed at the corresponding temperature. These results imply the establishment of short-range magnetic order above the antiferromagnetic transition temperature (T N) due to the dilution effect of nonmagnetic Ga3+ doping. [ABSTRACT FROM AUTHOR]

The excessive rainfall and irrigation amount in the facility herbal medicine production system (FHmPS) in China leading to a severe root rot disease of Panax notoginseng , which endangers root yield and quality, compromise economic profit and waste resources. Therefore, the objective of our research was to seek optimal irrigation and cultivation management strategy for FHmPS to improve Panax notoginseng production and economic benefit. A three-year (2019, 2020 and 2021) field experiment was conducted on Panax notoginseng under two shelter-cultivation [rain-shelter cultivation (Sr) and unrain-shelter cultivation (NSr)] at three deficit irrigation levels [ I 1= 65%W, I 2= 75%W, I 3= 85% W, where W was the irrigation quota when the upper and lower limits of irrigation are (100% ∼ 40%) θ FC under shelter-cultivation] to explore the combined practices effects on yield, quality, economic benefit, water productivity (WP) and nutrients uptake of Panax notoginseng , and to obtain the optimal irrigation and cultivation supply practice by the technique for order preference by similarity to ideal solution (TOPSIS). The results showed that SrI 2 obtained relatively high plant nutrient uptake, net profit, WP, and quality. SrI 2 significantly decreased the root rot incidence by 6–17.5% in comparison to other treatments. However, compared with rain-shelter cultivation, unrain-shelter cultivation weaken these effects in Panax notoginseng. Deficit irrigation promoted Sr to obtain higher WP than NSr. According to the result of TOPSIS, the comprehensive ranking of SrI 2 and SrI 3 were first and second among the practices, regardless of growing seasons and planting years. The SrI 2 significantly decreased the yield of Panax notoginseng by 5.4%− 20.8% in comparison to other treatments. SrI 2 and SrI 3 were highly recommended for facility herbal medicine production system (FHmPS) in the semi-arid area of Southwest China. [Display omitted] • The study proposed rain-shelter (Sr) based on traditional cultivation (NSr). • Deficit irrigation (I 2) and Sr decreased root rot rate of P. notoginseng. • The SrI 2 improved nutrient uptake and yield of P. notoginseng. • The SrI 2 improved PNS, economic benefit and WP of P. notoginseng [ABSTRACT FROM AUTHOR]

Farmland mulching and nitrogen application are the main agricultural management measures to improve soybean (Glycine max L.) production in dryland agriculture on the Loess Plateau. However, the interaction effects of various farmland mulching materials and nitrogen application rates on soybean leaf functionality and nitrogen nutrition status remains contradictory and inconclusive, and effective and rapid diagnostic of the leaf functionality and nitrogen status are still not well-understood. Therefore, the aim of this study is twofold: 1) to investigate the interactive effects of different mulching methods and nitrogen application levels on soybean leaf growth, physiological traits, and final grain yield throughout the entire growth period; 2) to establish a chlorophyll content monitoring model based on spectral parameters and a diagnostic model for soybean nitrogen status, and to assess the effectiveness of the latter in accurately diagnosing soybean nitrogen requirements. A two-year (2021 and 2022) field experiment, which consisted of four nitrogen levels (0, 60, 120 and 180 kg N ha−1) and four mulching strategies (NM: no mulching, SM: straw mulching, FM: film mulching, SFM: straw and film mulching), was conducted in the soybean growing seasons. Subsequently, nitrogen dilution curves were established based on chlorophyll content and the optimal spectral index to compute corresponding nitrogen nutrition index (NNI) values. The results indicated that: 1) FM, in comparison to SM and SFM, had the ability to delay leaf senescence, increase chlorophyll content, and improve physiological growth parameters, thereby increasing seed yield; 2) the application of 120 kg N ha−1 stood out, boosting soybean photosynthetic productivity and providing a solid foundation for high soybean yields; 3) the Random forest (RF) model had the highest accuracy in chlorophyll content estimation (R2 =0.854, RMSE=2.765 and MRE=5.758 % in validation set); and 4) both the nitrogen dilution curves constructed based on chlorophyll content and the optimal spectral index proved to be reasonably accurate in quantitatively diagnosing the nitrogen status of soybeans. Specifically, N0 and N180 indicated sustained nitrogen deficiency and excess, respectively, while N60 and N120 effectively met soybean's nitrogen requirements. In summary, the FMN120 effectively stabilized seed yield by regulating key functional traits in soybean leaves. This study provides a theoretical basis for the application of precision agriculture and remote sensing technology in monitoring and diagnosing plant nitrogen nutrition in soybean production. [Display omitted] • Film mulching enhances soybean yield. • 120 kg N ha−1 application promotes soybean photosynthesis, ensuring higher yields. • Spectral indices monitor crop physiology by precisely gauging chlorophyll content. • Optimized spectral index was used for nutrition diagnosis to enhance N management. [ABSTRACT FROM AUTHOR]

This study investigated the problem of QR decomposition for time-varying matrices. We transform the original QR decomposition problem into an equation system using its constraints. Then, we propose a continuous-time QR decomposition (CTQRD) model by applying zeroing neural network method, equivalent transformations, Kronecker product, and vectorization techniques. Subsequently, a high-precision ten-instant Zhang et al. discretization (ZeaD) formula is proposed. A ten-instant discrete-time QR decomposition model is also proposed by using the ten-instant ZeaD formula to discretize the CTQRD model. Moreover, three discrete-time QR decomposition models are proposed by applying three other ZeaD formulas, and three examples of QR decomposition are presented. The experimental results confirm the effectiveness and correctness of the proposed models for the QR decomposition of time-varying matrices. [ABSTRACT FROM AUTHOR]

It is a challenge to improve Panax notoginseng production and soil environment in arid area of Southwest China. Therefore, the objective of this study was to propose a new and promising alternate micro-sprinkler irrigation (D 2) to cope with the challenge based on moderate deficit micro-sprinkler irrigation (D 1) and slight deficit micro-sprinkler irrigation (D 3). A two-year greenhouse experiment was conducted to evaluate the root rot incidence of Panax notoginseng among of the D 1 , D 2 and D 3 treatments by analyzing the soil water content (SWC), soil microbial biomass carbon (SMBC), nitrogen (SMBN), total phosphorus (TP) and total potassium (TK), soil available nutrients(AN, AP and AK), soil enzyme activity, soil microbial structure, plant growth parameters, plant dry matter, nutrients uptake (N, P and K), and root rot incidence. Experiment treatments consisted of three irrigation amounts (D 1 , D 2 and D 3) and four organic fertilizer levels [500 (F 1), 1000 (F 2), 1500 (F 3), and 2000 (F 4) kg hm−2] in 2017 and 2018, respectively. All treatments were designed using a randomized complete block with three replications. The results indicated that no significant differences in growth parameters [PH (plant height), SD (stem diameter), and LAI (leaf area index)] of Panax notoginseng were found among of the D 1 , D 2 and D 3 treatments in 2017 and 2018. Compared with the D 1 and D 3 , the D 2 treatment significantly increased shoot dry weight (SDW), root dry weight (RDW), total N, P, K uptake and decreased SMBC, SMBN, TP, TK, AN, AP, AK and root rot incidence in 2017 and 2018. The result suggested the D 2 treatment had greater production advantages than the D 1 and D 3 treatments. In addition, compared with the F 3 treatment, other F treatments (F 1 , F 2 , and F 4) in the D 2 treatment significantly enhance total plant dry matter, total N, P and K uptake. However, root rot incidence significantly increased with the increase of application F levels, and D 2 F 3 can significantly decrease fungi/bacteria and fungi/actinomycetes in rhizosphere soil of healthy Panax notoginseng in 2018. According to analyzing the root rot incidence of different application F treatments, we found that 1500 kg hm−2 in the alternate micro-sprinkler irrigation might be recommended as an appropriate application F level to decrease root rot incidence of Panax notoginseng in the semi-arid area of Southwest China. [Display omitted] • Alternate irrigation and organic fertilization improved soil environment. • Alternate irrigation and organic fertilization (F 3) decreased root rot of plant. • Alternate irrigation and organic fertilization (F 3) improved yield of plant. • Organic fertilization (F 3) should be recommended to promote production. [ABSTRACT FROM AUTHOR]

For the spin-chain compound Ca 3 CoMnO 6 , the perfect Co/Mn ionic order causes the lost of ↑↑↓↓ long-range antiferromagnetic order. The lost long-range magnetic order results in the emergence of short range magnetic correlation interaction, forming the so called "order by disorder" phenomenon. In present paper, nonmagnetic Ga3+-doped Ca 3 CoMn 1- x Ga x O 6 compounds were prepared. The influence of Ga3+ substitution on the structure and magnetic order of Ca 3 CoMn 1- x Ga x O 6 were investigated. It is found that the solid solubility of Ga3+ cation in Ca 3 CoMn 1- x Ga x O 6 is 0.2 < x < 0.3. With introducing of Ga3+ cation, the oxidation state of some Co cations changes from Co2+ to Co3+. Magnetization measurements reveal that doped with nonmagnetic Ga3+ weakens the formation of short range magnetic order and enhances the antiferromagnetic transition temperature. As a result, more robust long rang antiferromagnetic order is established and the transition field that causes the ↑↑↓↓ spin state of Co–Mn–Co–Mn chain to ↑↑↓↑ state increases obviously. Meanwhile, the shortened short range magnetic correlation in Ga3+ doped Ca 3 CoMn 1- x Ga x O 6 can be driven more easily by the thermal activation energy and a quicker dynamic behavior was observed in time windows. • A series of Ga3+-doped Ca 3 CoMn 1- x Ga x O 6 compounds were synthesized. Our result reveals that the solid solubility of Ga3+ cation in Ca 3 CoMnO 6 is between x= 0.2 and x= 0.3. • Magnetization measurements indicate that doping with nonmagnetic Ga3+ could weak the formation of short range magnetic order and increase the antiferromagnetic transition temperature. • With introducing of Ga3+ cations, more robust long rang antiferromagnetic order is established and the transition field that causes the ↑↑↓↓ spin state of Co–Mn–Co–Mn chain to ↑↑↓↑ state enhances obviously. • In Ga3+ doped Ca 3 CoMn 1- x Ga x O 6 , the short range magnetic order is suppressed and more robust long rang antiferromagnetic order is established. [ABSTRACT FROM AUTHOR]

Future minimization, or say, discrete-time time-varying minimization, can be successfully solved by discrete-time Zhang neuronet (DTZN) models. A DTZN model is obtained through the discretization of a continuous-time Zhang neuronet (CTZN) model. However, most of the existing numerical differentiation formulas cannot be applied to discretizing a CTZN model for obtaining an effective DTZN model. Zhang et al discretization (ZeaD) formulas are the ones that can successfully address the problem about discretization. Recently, the four-point general ZeaD formula has been proposed (Hu et al., 2018), which can be applied to obtaining the four-point general DTZN model for future minimization. This paper focuses on researching the step-width-related stability of the four-point general DTZN model for future minimization. The step-width is a crucial parameter in the DTZN model. If the step-width is out of its corresponding interval, DTZN model does not converge in terms of residual error and fails in solving future minimization problem. By using Jury stability criterion, the analytic solution of step-width interval is proposed corresponding to the four-point general DTZN model. In addition, the optimal value of step-width is investigated, and the analytic solution of the optimal value is proposed as well. When step-width is equal to the optimal value, DTZN model has the fastest convergence rate to steady state with respect to residual error, and is farthest from instable state, thus having the best stability. The theoretical analyses are consistent with previous special-case investigations, and their correctness is confirmed by numerical experiments and results (i.e., numerics). [ABSTRACT FROM AUTHOR]

Recent research has identified some risk factors for problematic smartphone use. However, scarce research has examined the potential influence of envy on problematic smartphone use, and little is known regarding the mediating and moderating mechanisms underlying this relationship. This study tested whether envy would be positively related to adolescent problematic smartphone use, whether FOMO would mediate the relationship between envy and problematic smartphone use, and whether student-student relationship would moderate the pathways between envy and problematic smartphone use. This model was tested among 724 Chinese adolescents (mean age = 16.79 years, SD = 0.91). Participants completed measurements regarding envy, problematic smartphone use, FOMO, and student-student relationship. The results indicated that envy was positively related to problematic smartphone use and FOMO mediated this relationship. Moreover, moderated mediation analyses showed that all three pathways between envy and adolescent problematic smartphone use were moderated by student-student relationship. This study highlights the underlying mechanisms between envy and adolescent problematic smartphone use, which has important implications for the preventions and interventions of adolescent problematic smartphone use in this digital era. • Envy is positively related to problematic smartphone use (PSU). • FOMO mediates the link between envy and PSU. • Student-student relationship moderates the links between envy and PSU. [ABSTRACT FROM AUTHOR]

Abstract The mixing of donor and acceptor molecules in fluorescent nanoparticles offers an effective route to adjusting the emission properties of the nanoparticles. In this work, the electron donor 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) and the electron acceptor 2,4-bis[4-(diphenylphosphinyl)phenyl]-6-[4-(hexyloxy)phenyl]-1,3,5-triazine (BPOTZ-OR) were coprecipitated to form fluorescent nanoparticles. Efficient exciplex emission occurred in the nanoparticles owing to the good electron affinity and appropriate stacking distance between TAPC and BPOTZ-OR. The exciplex emission and monomer emission were easily tuned by simply changing the BPOTZ-OR/TAPC molar ratio. An appropriate combination produced white-light emission. The large red-shift of the emission from the exciplex, good stability under physiological conditions, and low toxicity suggest potential for this kind of nanoparticle to be an effective fluorescent probe for cell imaging. Graphical abstract Image 1 Highlights • Exciplex emission nanoparticles upon appropriate stacking distance were prepared. • Multicolor emission can be obtained by adjusting the donor-acceptor molar ratio. • The exciplex nanoparticles showed excellent performance in live cell imaging. [ABSTRACT FROM AUTHOR]

Abstract Quantitative knowledge of the spatial variability of soil infiltration processes caused by canopy rainfall redistribution has significant hydro-chemical consequences owing to their influence on nutrients leaching and groundwater recharge in agricultural ecosystems. The heterogeneity of throughfall and stemflow under the maize canopy was quantified in this study, and its subsequent effect on soil water distribution at the row scale was further examined. Throughfall at 15 locations within and between maize rows as well as stemflow was observed over three growing seasons of 2015, 2016 and 2017 on the Loess Plateau of China. Soil water content at five depths in the row and interrow positions were continuously monitored. The results showed that throughfall was significantly different among the five sampling sections between maize rows, with the highest throughfall in the center and a decreasing trend towards the maize row. Greater throughfall was observed on the windward side of the maize row than on the leeward side. These spatial patterns persisted for most rainfall events. However, much higher net rainfall (throughfall plus stemflow) was obtained in the row positions when stemflow was further considered. Net rainfall reaching the row positions resulted not only in earlier water infiltration, but also in deeper penetration. The results suggested that the presence of maize canopy altered the soil surface water flux and thus caused heterogeneous infiltration water in the soil, which has implications for guiding the placing of fertilizers/pesticides and soil erosion management in the maize field. Graphical abstract Unlabelled Image Highlights • Throughfall and stemflow heterogeneity under the maize canopy was explored. • Throughfall was the highest in the center and decreased towards the maize row. • Greater throughfall was observed on the windward side of the maize row. • Higher net rainfall was obtained in the row positions when considering stemflow. • Stemflow caused earlier water infiltration and deeper penetration in the row positions. [ABSTRACT FROM AUTHOR]

Highlights • Effects of irrigation and fertilizer supply on grain filling characteristics were explored. • Temporal dynamics of grain weight was simulated using determinate-growth equation. • Fertilizer had significantly influence the appearance time of maximum filling rate and growth termination time. • Grain weight percentage of spike weight and spike moisture content had extremely significant relationship with grain weight. • Mild water deficit and appropriate fertilization improved grain filling and productivity. Abstract In the semi-arid regions of the world, irrigation and fertilization are essential for cereals growth and production because of water shortages and unfertile soils. However, inappropriate water and fertilizer management always causes unstable grain weight and yield. This study aims to explore the responses of grain filling characteristics, grain weight and productivity of winter wheat to varying water and fertilizer supplies. A three-year (2014–2017) experiment was conducted on winter wheat (Triticum aestivum L. 'Xinong 979') under drip fertigation, with three irrigation rates and three fertilization rates. The temporal dynamics of grain weight was simulated using determinate-growth equation. The appearance time of maximum filling rate (t m) and growth termination time (t e) increased as fertilization rate increased, whereas the maximum and average filling rate increased and then had a slight decrease. The t m and t e decreased with the increase of water deficit, the mild water deficit obtained higher grain filling rate. The grain weight percentage of spike weight (GPS) and spike moisture content (SMC) had extremely significant correlations with grain weight. GPS tended to decrease one week before maturity, and declined with the increase in water stress. SMC decreased in a parabolic form, and exhibited a dramatic decline about one week before maturity. With the increase of water or fertilizer supply, the grain weight firstly increased and then decreased, where the mild water deficit and appropriate fertilization improve grain filling and productivity of winter wheat. [ABSTRACT FROM AUTHOR]

Abstract Time-varying nonlinear optimization (TVNO) problems are considered as important issues in various scientific disciplines and industrial applications. In this paper, the continuous-time derivative dynamics (CTDD) model is developed for obtaining the real-time solutions of TVNO problems. Furthermore, aiming to remedy the weaknesses of CTDD model, a continuous-time zeroing dynamics (CTZD) model is presented and investigated. For potential digital hardware realization, by using bilinear transform, a general four-step Zhang et al discretization (ZeaD) formula is proposed and applied to the discretization of both CTDD and CTZD models. A general four-step discrete-time derivative dynamics (general four-step DTDD) model and a general four-step discrete-time zeroing dynamics (general four-step DTZD) model are proposed on the basis of this general four-step ZeaD formula. Further theoretical analyses indicate that the general four-step DTZD model is zero-stable, consistent and convergent with the truncation error of O (g 4) , which denotes a vector with every entries being O (g 4) with g denoting the sampling period. Theoretical analyses also indicate that the maximal steady-state residual error (MSSRE) has an O (g 4) pattern confirmedly. The efficacy and accuracy of the general four-step DTDD and DTZD models are further illustrated by numerical examples. [ABSTRACT FROM AUTHOR]

We report the room-temperature synthesis of CuO/reduced graphene oxide (CuO/rGO) nanohybrids via a one-pot solution process, in which the reduction of GO and the formation of CuO were completed simultaneously at room temperature. The as-prepared sheet-like CuO with hundreds nanometer in sizes are well-mixed together uniformly with rGO in the nanohybrids. The gas sensors based on the as-prepared CuO/rGO nanohybrids were fabricated and used to detect low-concentration NO 2 gas (1–75 ppm) with excellent selectivity. Upon exposure to 1 ppm NO 2 at room temperature, the as-prepared CuO/rGO nanohybrids display a sensitive response of about 14 and the reponse time and recovery time are about 66 and 34 s, respectively. The low detection limit is evaluated to be as low as 60 ppb at room temperature. The high sensing response can be attributed to the large surface area of CuO/rGO nanohybrids and enhanced carrier transfer between NO 2 molecules and nanohybrids. We believe that this low-cost strategy provides a facile route to prepare other rGO-based nanohybrids for nanosensors. [ABSTRACT FROM AUTHOR]

Water and fertilizer are two important factors affecting crop growth and yield. Crop growth models are powerful tools for making irrigation and fertilization scheduling and predicting crop yield. The performance of crop models on potato under different irrigation amounts along with different N, P and K rates has been rarely evaluated, especially under drip fertigation. In this study, the accuracy of AquaCrop and DSSAT-SUBSTOR-Potato models in simulating potato growth, yield and water productivity under different drip fertigation regimes was compared. For model calibration and validation, a two-year field experiment with three irrigation levels (W 1 , 60% ET C ; W 2 , 80% ET C and W 3 , 100% ET C , where ET C was the crop evapotranspiration) and four fertigation (N-P 2 O 5 -K 2 O) rates (F 1 : 100–40–150 kg ha−1, F 2 : 150–60–225 kg ha−1, F 3 : 200–80–300 kg ha−1 and F 4 : 250–100–375 kg ha−1) was carried out in a sandy region of northwest China in 2018 and 2019. The statistical indicators showed that the AquaCrop model gave satisfactory predictions of canopy cover (R 2 ≥ 0.92, NRMSE ≤ 14.7%, d ≥ 0.96 and RMSE ≤ 10.8%), total dry matter (R 2 ≥ 0.92, NRMSE ≤ 25.0%, d ≥ 0.94 and RMSE ≤ 2.2 t ha−1), final dry tuber yield (R 2 ≥ 0.57, NRMSE ≤ 12.21%, d ≥ 0.82 and RMSE ≤ 0.83 t ha−1) and fresh tuber yield (R 2 ≥ 0.53, NRMSE ≤ 12.02%, d ≥ 0.81 and RMSE ≤ 4.91 t ha−1) in the four fertigation treatments (F 1 -F 4) under W 3 and W 2 during the two potato growing seasons. The final total dry matter and tuber yield under W 1 were over-estimated. The simulated water productivity and soil water content also agreed well with the observations (R 2 ≥ 0.91 , NRMSE ≤ 5.51%, d ≥ 0.94 and RMSE ≤ 0.48 kg m−3, and R 2 ≥ 0.40 , NRMSE ≤ 14.8%, d ≥ 0.77 and RMSE ≤ 11.5 mm). The simulation accuracy of DSSAT-SUBSTOR-Potato model was lower than that of AquaCrop model, which only showed a goodness of fit between simulated total dry matter, soil water content, tuber yield, water productivity and observations under high irrigation amount with high fertilization rate (W 3 F 4). Since the observed tuber yield increased with the increase of irrigation level (60–100% ET C) under the same fertigation rate, 120%ET C and 40%ET C were further simulated using the AquaCrop model to test the changes in tuber yield with further increased or decreased irrigation levels. The scenarios simulation showed that the tuber yield was only increased by 0.19%−1.52% under 120%ET C compared with that under 100% ET C , but 18.0% more irrigation water was consumed. Comprehensively considering water resources and tuber yield, the irrigation level of 100% ET C (W 3) along with fertigation (N-P 2 O 5 -K 2 O) rate of 200–80–300 kg ha−1 (F 3) was recommended for the sustainable potato production in the study region. The results of this study can provide guidance for the application of crop models in drip-fertigated potato. • AquaCrop and DSSAT-SUBSTOR-Potato were evaluated under various drip fertigation regimes. • AquaCrop adequately simulated the effects of irrigation and fertilization regimes on potato. • Simulation accuracy of DSSAT-SUBSTOR-potato was lower than that of AquaCrop. • 100% ET C along with N-P 2 O 5 -K 2 O rate of 200–80–300 kg ha−1 was recommenced for potato production. [ABSTRACT FROM AUTHOR]

The excessive irrigation and fertilization are common in wheat (Triticum aestivum L.) production in northwest China, which not only results in resources waste and environmental pollution, but also not necessarily guarantee high wheat yield due to the plant overgrowth. It is thus crucial to explore a suitable irrigation and fertilization strategy that benefits high-yield wheat cultivation by regulating post-anthesis dry matter accumulation and translocation. A consecutive four-season field experiment (2014–2018) was undertaken on drip-fertigated winter wheat with three irrigation levels based on the soil moisture content of moistening layers (W1: normal irrigation, W2: mild deficit irrigation, W3: severe deficit irrigation) and three fertilization (N-P 2 O 5 -K 2 O) rates (F1: 175–117–150 kg ha−1, F2: 125–84–108 kg ha−1, F3: 75–50–65 kg ha−1). The results showed that the logistic growth equation could well describe the accumulation process of aboveground dry matter with R 2 ranging 0.989 − 0.999 (P < 0.01). Water stress advanced the thermal time required from sowing to the maximum aboveground dry matter rate, while the maximum aboveground dry matter rate and average accumulated rate of aboveground dry matter increased with the increase of irrigation and fertilization regimes. Dry matter translocation showed a negative relationship with fertilization rate. However, both the post-anthesis dry matter accumulation and its contribution to total dry matter at maturity (CDMA) increased with the increasing fertilization rate. With the increase of water and fertilizer supply, dry matter translocation efficiency decreased, but CDMA showed the opposite trend. The post-anthesis dry matter accumulation was positively related to winter wheat grain yield. When the grain yield reached above 7.5 Mg ha−1 in northwest China, the post-anthesis accumulated dry matter should be more than 4.7 Mg ha−1. It was concluded that the mild deficit irrigation along with N-P 2 O 5 -K 2 O fertilization of 125–84–108 kg ha−1 enhanced the productivity of winter wheat by increasing the post-anthesis dry matter translocation and accumulation. ● Water stress advanced the thermal time required from sowing to maximum aboveground dry matter rate. ● Dry matter translocation showed a negative relationship with fertilization rate. ● Post-anthesis dry matter accumulation was positively associated with grain yield. ● Mild water deficit and 125–84–108 kg N-P 2 O 5 -K 2 O ha−1 increased post-anthesis dry matter translocation and grain yield. [ABSTRACT FROM AUTHOR]

Precise nutrient diagnosis is the basis of accurate simulation of maize (Zea mays L.) grain yield and high-efficient utilization of resources under the changing climate. However, the combined effects of supplementary irrigation and fertilizer application on plant stoichiometry of various maize cultivars in water-limited and nutrient-deficient regions are still poorly understood. A three consecutive year field experiment (2015−2017) was conducted on two maize cultivars (QL14 and ZD958) in northwest China, with two irrigation treatments (RF: rain-fed and DI: drip irrigation) and two fertilization treatments (F0: no fertilization and F1: local fertilization practice). The results showed that the radiation use efficiency for biomass yield of QL14 with fertilization under drip irrigation was increased by 7.39% than that of ZD958. DI (70.19 kg kg−1) and ZD958 (68.55 kg kg−1) obtained significantly higher physiological efficiency of nitrogen fertilizer than RF (59.52 kg kg−1) and QL14 (61.17 kg kg−1), respectively. Both plant and grain N:P ratios under F1 were higher than those under F0. QL14 had significantly higher grain N:P ratio (4.64) than ZD958 (4.26) under DIF1. Grain yield was increased obviously when grain N:P ratio and plant N:K stoichiometry were greater than 4.0 and 1.2, respectively. The newly released maize cultivar (QL14) was highly recommended as forage and cereal crops, since QL14 obtained significantly higher leaf and stem dry matter even under severe drought and low soil fertility conditions. Our study provides an opportunity to achieve high-yielding maize systems in northwest China and maybe other regions with similar environments, and the data will help inform policies and strategic plans for the effective use of water and fertilizer resources. • Nutrient stoichiometry and radiation use efficiency of two maize cultivars were explored. • There was a linear relationship between grain N and P uptake. • Grain yield was increased obviously when grain N:P ratio was greater than 4.0. • QL14 with higher leaf and stem dry matter was recommended as forage and cereal crops. [ABSTRACT FROM AUTHOR]

Soil mulching, e.g. straw mulching (SM) and ridge-furrow plastic film mulching (RP), has been reported to promote rainfed crop production in semi-arid regions, but its applicability in improving maize yield and especially yield stability in semi-humid drought-prone regions has been rarely explored. The capture and utilization of thermal, light, water and nutrients resources by maize plants under various soil mulching conditions are also poorly understood. A consecutive five-season field experiment was conducted on rainfed maize in a semi-humid drought-prone region of China during 2015–2019 to assess the effects of SM and RP on soil hydrothermal conditions, radiation interception, photosynthesis, evapotranspiration and grain yield stability, profitability and resources use efficiency compared with non-mulching (NM). The results showed that RP enhanced soil hydrothermal conditions, promoted the conversion of water from soil evaporation to plant transpiration and improved water productivity by 10.9%−203.2% compared with NM (P < 0.05). Although the growth duration was shortened, the accumulative soil thermal time and intercepted photosynthetically active radiation under RP were still 4.4% and 3.9% higher, with average increases in thermal time use efficiency by 23% and radiation use efficiency by 24%, which resulted in significantly higher nutrients accumulation (by 6.7%−19.7% for nitrogen and 4.1%−42.0% for phosphorous), grain yield (by 9.5%−186.4%) and yield stability (by 38.1%). These improvements were particularly pronounced in normal and dry years (2015, 2016 and 2017). No significant difference existed in maize's capacity of absorbing water and nutrients and maize productivity between SM and RP under sufficient precipitation supply (2018 and 2019). The average net profit was highest under RP, especially in dry and normal years, while SM could achieve comparable net profit to RP in wet years. Overall, RP was preferable for rainfed maize production in semi-humid drought-prone regions in any precipitation year, while SM can be an alternative mulching practice in wet years. These results can improve our understanding of how RP and SM enhance rainfed maize productivity by improving resources capture and use efficiency. ● Mulching practices effects on maize yield stability and resources use efficiency were explored. ● Ridge-furrow mulching increased thermal time use efficiency and radiation use efficiency. ● Ridge-furrow mulching obtained the highest grain yield, yield stability and net profit. ● No significant differences existed between ridge-furrow and straw mulching in wet years. ● Ridge-furrow mulching was more preferable for maize production in any precipitation year. [ABSTRACT FROM AUTHOR]

The ridge-furrow plastic mulching system has been reported to increase crop yield and water-nitrogen use efficiency in semi-arid and semi-humid regions, but the effects of plant density, nitrogen (N) rate and supplemental irrigation on chlorophyll, photosynthesis, root growth and seed yield of soybean under ridge-furrow plastic mulching are poorly understood. A two-year field experiment (2019 and 2020) was conducted on soybean in a split-split plot design, with two plant densities (D 16 : 160,000 plants ha−1; D 32 : 320,000 plants ha−1) as main plots, two N rates (N 30 : 30 kg N ha−1; N 60 : 60 kg N ha−1) as sub plots, and two irrigation levels (W 0 : rainfed; W 30 : supplemental irrigation of 30 mm at the flowering-podding stage) as sub-sub plots. The results showed that plant density, N rate and supplemental irrigation had significant effects on leaf chlorophyll content, chlorophyll fluorescence parameters, photosynthesis, aboveground/root growth and seed yield. Increasing plant density enhanced leaf area index (LAI) by 31.9% and aboveground biomass (AGB) by 59.4%, seed yield by 27.4%, water use efficiency of seed yield (WUE s) by 27.9% and nitrogen partial factor productivity (NPFP) by 26.6%. Increasing N rate increased leaf chlorophyll content by 11.9% and photosynthetic rate by 5.5%, thereby increasing LAI by 11.5%, AGB by 10.3%, seed yield by 8.9% and WUE s by 8.2%. Supplemental irrigation increased chlorophyll content by 7.6% and photosynthetic rate by 3.7%, thereby increasing LAI by 4.7%, AGB by 11.0%, seed yield by 4.7% and NPFP by 4.0%, while supplemental irrigation only increased WUE s under D 32. Compared with D 16 N 30 W 0 , D 32 N 60 W 30 enhanced seed yield by 44.0% and WUE s by 37.0%, but reduced NPFP by 28.8%. Compared with D 32 N 30 W 30 , D 32 N 60 W 30 increased both seed yield and WUE s by 8.5%, but it reduced NPFP by 45.5% with 100% higher N input. LAI, AGB, WUE s , NPFP and some leaf physiological (EXC, Chl a /Chl b , EWT leaf and L s) and root (TRLD, TRVD and TRSD) indexes were closely related to soybean yield. This study provides a better understanding how plant density, N rate and supplemental irrigation improved soybean productivity and water-nitrogen use efficiency by regulating chlorophyll, photosynthesis and aboveground/root growth. ● Plant density, nitrogen rate and supplemental irrigation effects on soybean were explored. ● They significantly affected chlorophyll, photosynthesis, root growth and seed yield. ● D 32 N 60 W 30 enhanced seed yield by 44.0% and WUE s by 37.0%, but reduced NPFP by 28.8% than D 16 N 30 W 0. ● D 32 N 60 W 30 increased seed yield and WUE s by only 8.5%, but reduced NPFP by 45.5% than D 32 N 30 W 30. [ABSTRACT FROM AUTHOR]

The over-application of irrigation and chemical fertilization in the greenhouse vegetable production system (GVPS) in China can jeopardize fruit quality, compromise economic profit and waste resources. Seeking optimal water and fertilizer supply mode for GVPS is urgently required to improve resource use efficiency and economic benefit. A greenhouse experiment was conducted during four consecutive tomato growing seasons to investigate the combined effects of various irrigation levels and fertilization practices on yield, fruit quality, economic benefit, water use efficiency (WUE) and nitrogen use efficiency (NUE) of drip-fertigated tomato, and to obtain the optimal water and fertilizer supply practice by the principal component analysis (PCA). On the basis of full irrigation (W1: 100%ET c , ET c was the crop evapotranspiration), two deficit irrigation levels (W2: 75%ET c , W3: 50%ET c) were set. Except for the conventional fertilization practice used by local farmers (CC: chicken manures for basal application and chemical fertilizer for topdressing), four other fertilization practices were considered, including soluble organic fertilizers for topdressing (SO), soluble chemical fertilizers for topdressing (SC), both soluble organic and chemical fertilizers for topdressing (SOSC), and a control with no fertilizer application under full irrigation (CK). The results showed that SOSC obtained relatively high plant nitrogen uptake, net profit and WUE, and significantly improved tomato yield. Organic fertilizers addition reduced nitrate content in tomato fruits. Deficit irrigation promoted CC to obtain higher WUE than SC. According to the result of PCA, the comprehensive ranking of SOSC was first among the fertilization practices, regardless of irrigation levels and growing seasons. W1SOSC and W2SOSC were highly recommended for greenhouse tomato production in spring and autumn seasons, respectively. ● Drip irrigation and fertilization effects on yield and economic benefit of tomato were explored. ● Organic fertilizers addition reduced nitrate content in tomato fruits. ● The comprehensive ranking of soluble organic and chemical fertilizers for topdressing was first. ● Soluble organic and chemical fertilizers combined with full irrigation or 75% full irrigation was recommended. [ABSTRACT FROM AUTHOR]

Increasing the capacity of plants to assimilate carbon (source), or to tap into the internal carbon reservoir (sink), has the potential of realizing high and stable yield under a more variable climate. A three-year field experiment was conducted to explore the source-sink relationships of two maize (Zea mays L.) cultivars in response to various water and fertilizer inputs, and evaluate the yield sustainability in northwest China. There were two fertilization rates (unfertilized, F0; fertilized, F1), two irrigation strategies (rainfed, RF; supplemental drip irrigation, DI) and two maize cultivars (ZD958 and QL14). The results showed that the newly released maize cultivar (QL14) had higher leaf chlorophyll content at the silking and grain-filling stages than the old one (ZD958); meanwhile, QL14 had higher root dry matter at maturity than ZD958 under DIF1. The aboveground and root dry matter increased with the amount of water and fertilizer, while the root-shoot ratio decreased. Cultivar significantly affected the vegetative organ dry matter partitioning, especially under severe drought at the silking stage. QL14 had stronger root system and larger leaf dry matter than ZD958, and was more drought-resistant under serious water-stressed conditions. Dry matter translocation (DMT) was crucial for grain yield formation under limited nutrients conditions, and ~55% of total dry matter at maturity was accumulated at the grain-filling stage under adequate water and fertilizer conditions. DIF1 had higher sustainable yield index (SYI) than RFF1. There was no significant difference in grain yield between the two maize cultivars under DIF1, but the average SYI of QL14 (0.94) was greater than that of ZD958 (0.89). The present study indicates that the newly released maize cultivar (QL14) with stronger root system and stay-green characteristics is beneficial for increasing drought resistance and keeping yield stable in the semi-humid and drought-prone region of northwest China. ● Source-sink relationship and yield stability of two maize cultivars were explored. ● Dry matter increased with water and fertilizer supply, while root-shoot ratio decreased. ● Dry matter translocation of maize was crucial for yield formation. ● Stronger root and stay-green of maize cultivar kept yield stability. [ABSTRACT FROM AUTHOR]

Nitrogen (N), phosphorus (P) and potassium (K) are essential elements for crop growth. The absorption, accumulation process and distribution of these nutrients affect not only the growth and grain yield, but also the grain quality of wheat (Triticum aestivum L.). Various fertilization and irrigation practices can influence wheat growth as well as the absorption and utilization of nutrient elements. A four-season (2014–2018) experiment was conducted on drip-fertigated winter wheat on the Loess Plateau of China with three irrigation levels and three fertilization rates. Irrigation rates included normal irrigation (W1), mild deficit irrigation (W2) and more severe deficit irrigation (W3), while fertilization rates (N-P 2 O 5 -K 2 O) included F1 (175–117–150 kg ha−1), F2 (125–84–108 kg ha−1) and F3 (75–50–65 kg ha−1). The results showed that NPK uptake in aboveground biomass decreased as the water stress increased, but there was no significant difference between W1 and W2. When sufficient water and fertilizer were applied, the stem, leaf and rachis + glume obtained higher proportion of NP, while grain nitrogen and phosphorus harvest index (NHI and PHI) decreased. When the supply of water and fertilizer was insufficient, NHI and PHI increased, and the proportion of vegetative organs was relatively low. The average NPK requirement for 100 kg grain (GNR, GPR and GKR) varied 1.93–3.03, 0.37–0.41 and 2.26–2.93 kg over the four seasons. GNR and GKR increased with increasing irrigation and fertilization regimes. With the increase of irrigation amount, irrigation water use efficiency (IWUE) first increased and then decreased slightly, and the maximum IWUE occurred under W2. Yield and IWUE increased with the increase of fertilization rate, but there was no significant difference between F1 and F2. F2 obtained higher partial factor productivity than F1. F1 and F2 had no significant difference in protein content and protein yield, but they obtained significantly higher values than F3. Therefore, W2F2 was an efficient water and fertilizer management practice for drip-fertigated winter wheat, which promoted nutrients transfer to grains without significantly reducing grain yield and protein. • Drip fertigation effects on nutrient uptake and utilization of winter wheat were explored. • When sufficient water-fertilizer applied, grain nitrogen and phosphorus harvest index decreased. • Average NPK requirement for 100 kg grain were 1.93–3.03, 0.37–0.41 and 2.26–2.93 kg, respectively. • W2F2 promoted nutrients transfer to grains without significantly reducing yield. [ABSTRACT FROM AUTHOR]

Given water resources scarcity in Northwest China and the urgent need for the integration and optimization of scientific and technological resources in facility agriculture, this experiment explored the appropriate water and fertilizer management measures for greenhouse sweet pepper under fertilization in Northwest China. A two-year drip fertigation sweet pepper experiment was conducted in a solar greenhouse, with four irrigation levels (W 1 : 105% ET C , W 2 : 90% ET C , W 3 : 75% ET C , W 4 : 60% ET C) and four nitrogen levels (N 1 : 300 kg/ha, N 2 : 225 kg/ha, N 3 : 150 kg/ha, N 4 : 75 kg/ha). The results showed that above-ground dry matter accumulation (DMA), yield, harvest index (HI), and water use efficiency (WUE) of sweet pepper increased first and then decreased with the increase of irrigation/nitrogen amounts under the same nitrogen/irrigation levels. The partial factor productivity of nitrogen (PFPN) decreased significantly with the increase of nitrogen application rate, while it increased first and then decreased with the increase of irrigation level. The PFPN reached a peak at W 2 level, despite no significant difference between W 2 and W 3 levels. With the increase of nitrogen application rate, soluble sugar and vitamin C content increased first and then decreased with a maximum at N 3 level; nitrate content increased with the increase of nitrogen application rate, and there was no significant difference between N 4 and N 3 levels. The contents of soluble sugar and nitrate nitrogen decreased with the increase of irrigation amount, and they did not differ between W 1 and W 3 levels at N 3 level; the vitamin C content increased first and then decreased with the increase of irrigation amount, reaching the maximum in W 2 or W 3 treatments. Considering the shortage of water resources in the study area, the W 3 N 3 treatment (75% ET C , 150 kg/ha) could be recommended as the optimal drip fertigation strategy. Results showed that the optimal value of sweet pepper (the best confidence intervals of 85%) was achieved at the irrigation water and nitrogen amount of 78.2–80.8% ET C and 164.5–189.5 kg/ha, respectively. This study provides scientific basis for water and nitrogen management of high yield, quality, and benefit planting of facility sweet pepper in Northwest China. • Water and nitrogen had significant effects on sweet pepper harvest index. • Vitamin C increased first and then decreased with increase of water and nitrogen. • WUE decreased with the increase of irrigation amount. • The precise water and nitrogen application interval were determined. [ABSTRACT FROM AUTHOR]

Irrigation and fertilization are the two most important measures to ensure the agricultural development in arid regions. However, there is still a lack of reasonable irrigation and fertilization strategy in Xinjiang, the largest cotton producing area in China, which causes a waste of resources and a reduction in cotton yield and pollutes the environment. This study investigated the effects of four irrigation amounts (W 0.6 : 60% ET c , W 0.8 : 80% ET c , W 1.0 : 100% ET c and W 1.2 : 120% ET c , where ET c is the crop evapotranspiration) and four nitrogen rates (N 250 -250 kg N ha-1, N 300 -300 kg N ha-1, N 350 -350 kg N ha-1 and N 400 -400 kg N ha-1) on seed cotton yield, nitrogen nutrition status and soil nitrogen residue, so as to explore the optimal water-nitrogen coupling strategy to increase cotton production and water-fertilizer use efficiency while reducing environmental pollution. The nitrogen dilution curves were built to assess the nitrogen nutrition status of cotton. The results showed that increasing irrigation amount increased dry matter and seed cotton yield, but decreased harvest index. Nitrogen application enhanced the nitrogen concentration and accumulation in cotton. Irrigation decreased the nitrogen concentration, but increased the nitrogen accumulation by increasing the dry matter. The highest total plant nitrogen accumulation was obtained under W 1.2 N 400 , 223.88 kg ha-1 in 2018 and 242.77 kg ha-1 in 2019. With the increase of irrigation amount, agronomic nitrogen utilization efficiency (aNUE) first increased and then decreased. Increasing irrigation amount increased nitrogen recovery efficiency (NRE), but reduced physiological nitrogen utilization efficiency (pNUE). pNUE and aNUE decreased with the increasing nitrogen rate, while NRE first increased and then decreased. Soil NO 3 − -N content increased with the increase of nitrogen rate. Irrigation reduced NO 3 − -N content in the surface soil (0–30 cm), while increased that in the deeper soil (40–80 cm). The optimal nitrogen nutrition status was found under W 1.0 N 300 , followed by W 1.0 N 350. Furthermore, the optimal dry matter, seed cotton yield, NRE and total nitrogen accumulation were obtained under W 1.0 N 350 , which was considered as the optimal combination of irrigation amount and nitrogen rate in this study. • Irrigation amount and nitrogen rate effects on cotton nitrogen uptake, utilization and soil nitrogen residue were explored. • A uniform critical nitrogen dilution curve was established for diagnosing cotton N nutrition status. • The best combination of irrigation amount and nitrogen rate for optimal cotton nitrogen nutrition status was put forward. • The optimal dry matter, seed cotton yield, NRE and total nitrogen accumulation were obtained under W 1.0 N 350. [ABSTRACT FROM AUTHOR]

Congenital abnormalities of the kidney and urinary tract are among the most common birth defects, affecting 3% of newborns. The human kidney forms around a million nephrons from a pool of nephron progenitors over a 30-week period of development. To establish a framework for human nephrogenesis, we spatially resolved a stereotypical process by which equipotent nephron progenitors generate a nephron anlage, then applied data-driven approaches to construct three-dimensional protein maps on anatomical models of the nephrogenic program. Single-cell RNA sequencing identified progenitor states, which were spatially mapped to the nephron anatomy, enabling the generation of functional gene networks predicting interactions within and between nephron cell types. Network mining identified known developmental disease genes and predicted targets of interest. The spatially resolved nephrogenic program made available through the Human Nephrogenesis Atlas (https://sckidney.flatironinstitute.org/) will facilitate an understanding of kidney development and disease and enhance efforts to generate new kidney structures. [Display omitted] • Mouse and human kidneys undergo a conserved stereotypical developmental program • Transcriptomes were mapped to protein-based developmental models • Data predict lineage relationships in early human nephron development • View lineage and interaction predictions: https://sckidney.flatironinstitute.org/ Lindström et al. show that mouse and human nephrogenesis follow evolutionary conserved and stereotypical programs. Spatial mapping of transcriptional profiles predicts cell intermediates and regulatory interactions at play in development and disease. A web interface facilitates viewing and analysis of these findings. [ABSTRACT FROM AUTHOR]

• Mulching method and nitrogen type effects on maize yield and gaseous emissions were explored. • No differences in yield and NUE existed between ridge-furrow mulching and straw mulching. • GWP and GHGI increased under ridge-furrow mulching, but decreased under straw mulching. • Urea + NBPT minimized NH 3 volatilization, while Urea + DMPP mitigated N 2 O emission. • Straw mulching with Urea + DMPP was recommended for sustainable dryland maize production. Understanding the comprehensive impact of soil mulching and nitrogen (N) fertilization on agronomy, economy and environment is important for developing sustainable dryland agriculture. A two-year experiment was conducted on dryland maize (Zea mays L.) in a sub-humid but drought-prone climate zone to explore the responses of grain yield, N use efficiency (NUE), economic benefit, ammonia (NH 3) volatilization and greenhouse gas emissions to various mulching methods (NM: non-mulching, SM: wheat (Triticum aestivum L.) straw mulching and RF: ridge-furrow cultivation with plastic film mulching on the ridge) and N types (U: urea, U + CRU: mixture of urea and controlled-release urea at a ratio of 3:7, U + DMPP: urea with 2 % 3, 4-dimethylpyrazole phosphate and U + NBPT: urea with 2 % N -(n -butyl) thiophosphoric triamide). The results showed that RF and SM significantly increased grain yield and NUE, and decreased residual soil mineral N in the 0−200 cm soil layer relative to NM, but the differences in these indices were not significant between RF and SM. The net benefit under SM was comparable to that under RF (1558.5 and 1613.6 USD ha−1). The RF treatment significantly increased global warming potential (GWP) and greenhouse gas intensity (GHGI) by 33.7 % and 20.4 % compared with NM, and by 71.9 % and 67.5 % compared with SM. Compared with urea, U + CRU, U + DMPP and U + NBPT exhibited promoting effect on grain yield and NUE, but decreased residual soil mineral N. Compared with U, U + NBPT and U + DMPP produced much lower NH 3 volatilization and nitrous oxide (N 2 O) emission, respectively. Compared with U, U + CRU also reduced NH 3 volatilization and N 2 O emission, but its economic benefit was 4.9 % lower. Both U + DMPP and U + NBPT exhibited inhibitory effect on methane (CH 4) oxidation, but the CH 4 pattern under U + CRU was inconsistent in the two years. The smallest GWP and GHGI were generally observed under U + DMPP among various N types. The interaction of mulching method and N type had significant influence on grain yield in 2019, CO 2 emission in 2018, N 2 O emission, GWP and GHGI in both years. In conclusion, wheat straw mulching with nitrification inhibitor application achieved better balance among agronomic, economic and environmental benefits for dryland maize in northwest China. [ABSTRACT FROM AUTHOR]

Soil mulching and nitrogen application have long been applied in rainfed agriculture, but their interactive effects on crop productivity and especially environments remain poorly understood. Field experiments were carried out in 2018 and 2019 to investigate the responses of grain yield, water productivity, nitrogen use efficiency, economic benefit and greenhouse gas (N 2 O, CO 2 and CH 4) emissions of rainfed summer maize in northwest China to various mulching practices (NM: no mulching, SM: straw mulching, and RF: ridge-furrow cultivation with film mulching on the ridge), nitrogen rates (N1: 100 kg N ha−1, N2: 200 kg N ha−1 and N3: 300 kg N ha−1) and their interactions. The results showed that there were no significant differences in grain yield, water productivity and NUE between RF and SM irrespective of nitrogen rates, but RF and SM significantly increased grain yield by 12.4% and 7.9%, water productivity by 13.7% and 10.2%, and partial factor productivity by 12.1% and 7.2% compared with NM (7620.8 kg ha−1, 18.86 kg ha−1 mm−1 and 45.3 kg kg−1), respectively. SM obtained comparable net income to RF under N2 (1567.0 and 1632.4 USD ha−1) and N3 (1593.9 and 1709.9 USD ha−1). Grain yield and net income increased by 12.0% and 14.8% from N1 (7408.6 kg ha−1 and 1356.6 USD ha−1) to N2, and by only 5.5% and 3.6% from N2 (8297.3 kg ha−1 and 1558.0 USD ha−1) to N3, respectively. Water productivity was increased by 14.3% from N1 (18.6 kg ha−1 mm−1) to N2, but it decreased by 3.3% in 2018 and increased by 3.0% in 2019 from N2 (23.2 and 19.4 kg ha−1 mm−1) to N3. Both SM and RF increased CO 2 emission compared to NM, while N 2 O emission decreased under SM and increased under RF. RF increased soil CH 4 absorption, while CH 4 patterns were not consistent under SM. SM significantly decreased global warming potential by 23.1% and greenhouse gas intensity by 29.0% relative to NM (405.4 kg CO 2 -eq and 52.0 kg CO 2 -eq t−1 yield), but they were significantly increased by 62.1% and 22.4% compared with NM under RF, respectively. Compared to N1 (74.09 kg kg−1), N2 and N3 decreased partial factor productivity by 44.0% and 60.9%, respectively. N rate had little influence on CO 2 and CH 4 emissions, but it significantly promoted N 2 O emission. There were significant interacting effects of mulching practice and nitrogen rate on N 2 O emission and global warming potential. In conclusion, straw mulching with 200 kg N ha−1 achieved a better balance between agronomic, economic and environmental benefits of rainfed summer maize in northwest China. • Mulching practice and N rate effects on maize yield and GHG emissions were explored. • No significant differences existed in GY, WP, NUE and SNR between RF and SM. • Straw mulching decreased GWP by 23.1% and GHGI by 29.0% compared with NM. • GWP and GHGI under RF were 62.1% and 22.4% higher than those under NM. • Straw mulching with 200 kg N ha−1 was recommended for sustainable maize production. [ABSTRACT FROM AUTHOR]

• Full irrigation (100 %ET c) improved plant growth and yield of greenhouse tomato. • 75 %ET c obtained higher WUE and lower unmarketable yield. • 100 %ET c tended to shorten rapid growth period of aboveground biomass and improve maximum growth rate. • The lowest total water consumption occurred at the blooming and setting stage. Agriculture is the largest consumer of scarce water resources and irrigation serves as the sole source of water for greenhouse tomato production. It is an urgent task to seek an appropriate deficit irrigation strategy that is beneficial for high marketable yield, fruit quality, saving irrigation water and ultimately improving water use efficiency. A four-season experiment was conducted on drip-irrigated greenhouse tomato during Autumn 2015-Spring 2017 with three irrigation regimes, i.e., 100 %ET c (crop evapotranspiration) (W1), 75 %ET c (W2) and 50 %ET c (W3). The results showed that aboveground biomass, leaf area index (LAI), plant height and fruit yield increased with increasing irrigation amount. However, soluble solids, vitamin C and soluble sugar of tomato fruits were lowest under W1. W2 markedly reduced unmarketable fruits and more small-sized fruits were harvested at the late stage under W1. Through fitting the relationship between cumulative temperature and aboveground biomass using logistic equations, it was found that average duration of the rapid growth period (t d) and the time when growth rate reached the maximum value (t m) increased as irrigation amount decreased. Conversely, the maximum growth rate during the rapid growth period (v m) decreased with the increase of water deficit. The highest total water consumption (278.05 mm), lowest total yield water use efficiency (25.12 kg m−3) and marketable yield water use efficiency (22.87 kg m−3) were obtained under W1. The smallest total water consumption (27.01–50.75 mm) occurred at the blooming and setting stage. Based on the results of path analysis, aboveground biomass and average fruit weight were important indexes affecting yield positively. It is concluded that deficit drip irrigation with 75 %ET c has the potential of supporting tomato growth, improving marketable yield and WUE as a result of less unmarketable yield and bigger fruit size. [ABSTRACT FROM AUTHOR]

(a) The M t /M t=0 curves of the Ca 3 Co 1+ x Mn 1- x O 6 (x = 0, 0.05, and −0.05) samples measured by ZFC after cooling the samples to 5 K, switching on a 5 T field, and then recording the magnetization as a function of the time. (b) The M t /M t=0 curves measured by first magnetizing the samples in H = 5 T at T = 5 K, switching off the magnetic field, and then recording the remnant magnetization. • Structure and magnetization of Co/Mn compensated Ca 3 Co 1+x Mn 1-x O 6 (x = 0, 0.05, −0.05) were investigated. • The short range magnetic correlation of Ca 3 Co 1+x Mn 1-x O 6 compounds can be suppressed by tuning the Co/Mn ratio. • The faster dynamic characteristics are manifested for x =−0.05 and x = 0.05 samples. A series of Ca 3 Co 1+ x Mn 1- x O 6 (x =0, 0.05, and −0.05) compounds were synthesized that crystallized into rhombohedral structures with space group R-3c. Compared with the parent compound (x =0), the freezing peak of the Co/Mn compensated samples (x =±0.05) shifted to lower temperatures and became smeared. In addition, the coercive field H c and remnant magnetization M r of the compensated samples measured at T =130 K also decreased. This study found that the short-range magnetic order of Ca 3 Co 1+ x Mn 1- x O 6 compounds could be suppressed by tuning the Co/Mn ratio. Due to the suppression, the freezing magnetic moments in the compensated samples easily reversed magnetic field direction. Therefore, compared with the x =0 sample, the time dependence of magnetization relaxation in the compensated samples exhibited a sharp decay rate, indicating fast dynamics. [ABSTRACT FROM AUTHOR]

No-tillage with limited supplementary irrigation is promising for improving crop growth and ensuring sustainable crop yield in semi-arid and semi-humid areas defined by their water scarcity and uneven seasonal precipitation distribution. Choosing effective irrigation methods and scheduling to improve irrigation water use efficiency (IWUE) and reduce the risk of soil nitrate leaching has become increasingly necessary for crop management. Field experiments were conducted on no-tillage summer maize over four consecutive years from 2014 to 2017 in a semi-humid and drought-prone region of Northwest China. Four irrigation strategies were used, i.e. rain-fed (RF, no irrigation), conventional flood irrigation (CK), full drip irrigation (FI) and deficit drip irrigation (DI, 75% FI). The results indicated that supplemental irrigation mitigated the drought stress resulting in improving maize growth and a stable, sustainable yield. Plant height, leaf area index and aboveground biomass of the DI treatment were lower than those of the CK and FI treatments, while the DI treatment produced insignificantly lower grain yield and increased grain nitrogen content. The DI treatment promoted the transfer of nutrients from vegetative organs to reproductive organs. The IWUE of the DI treatment was increased by 22.1%–27.3% and 28.4%–48.6% compared with the CK and FI treatments during the four growing seasons, respectively. Soil NO 3 −-N of the CK treatment was mainly distributed below 40 cm soil depth, while most soil NO 3 −-N remained above 40 cm in the FI and DI treatments, implying lower levels of nitrate leaching compared with the conventional flood irrigation. In conclusion, deficit drip supplementary irrigation is a sustainable agricultural production strategy that improves water use efficiency, maintains stable yield and alleviates the risk of soil nitrate pollution in the no-tillage agrisystem of arid and semi-arid regions. Image 1 • Deficit drip irrigation increased IWUE by 22.1–27.3% and 28.4–48.6% compared with flood and full drip irrigation. • Deficit drip irrigation promotes nutrients transfer to reproductive organs and increases grain N content. • Possibility of NO 3 −-N leaching under drip irrigation management was smaller than that of flood irrigation. • Deficit drip irrigation saved irrigation water and did not significantly reduce maize yield. [ABSTRACT FROM AUTHOR]

• Irrigation and fertilization effects on grain macronutrient concentrations were explored. • Grain N concentration increased and then decreased with increasing fertilization or decreasing irrigation. • Grain P concentration decreased with the increase in irrigation and fertilization rates. • Grain yield and grain N concentration exhibited a positive relationship. • Mild water deficit and appropriate fertilization improved grain NPK uptake and productivity. Understanding the grain macronutrient uptake requirements with increased grain yield is essential to optimize the irrigation and fertilizer management for high-yield and high-quality wheat production to meet the increasing future food demand. A three-season control experiment was conducted on drip-fertigated winter wheat to investigate the dynamic changes in concentrations of nitrogen (N), phosphorus (P) and potassium (K) under varying water and fertilizer supply regimes. The results showed that the grain N concentration firstly decreased and then increased during grain filling. Specifically, it firstly increased and then decreased with the increase in fertilization rate, while it firstly decreased and then increased with increasing irrigation rate. The average of grain P concentration decreased with the increase in irrigation and fertilization rates. The grain K concentration showed a slow decline trend at the initial grain-filling stage until reaching a stable value at the mid-filling stage, and it increased with the increase in fertilization rate. Grain NPK uptake at maturity increased with increasing fertilization rate under normal irrigation, while the mild water deficit was found to promote grain NPK uptake. Grain yield and grain N concentration exhibited a positive relationship, and both irrigation and fertilization had significant effects on grain yield and NPK uptake. The grain protein content and N:P ratio were mainly affected by fertilization. The mild water deficit and appropriate fertilization rate improved the grain NPK uptake and production of winter wheat with higher grain protein content, which was conducive to the development of water- and fertilizer-saving agriculture. [ABSTRACT FROM AUTHOR]