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To evaluate the impact of perioperative comprehensive nursing intervention on postoperative urinary incontinence, various aspects of patient well-being were assessed. The comprehensive group, that received the nursing intervention, demonstrated significant improvements in self-care skills, health knowledge level, self-care responsibility, and self-concept compared to the standard group. The findings indicate that perioperative comprehensive nursing intervention has a remarkable effect on patients undergoing laparoscopic radical prostatectomy. This nursing intervention not only effectively improves postoperative urinary incontinence and alleviates negative emotions, such as anxiety and depression. Therefore, the implementation of this nursing intervention model is highly recommended for clinical practice and wider application. [ABSTRACT FROM AUTHOR]

Hydrogen embrittlement is an important technological problem underpinning failure of many structural elements. It has been extensively investigated in the literatures; however, several open issues remain that prevent a full understanding of this phenomenon. One important issue is the uncertain knowledge of how hydrogen atoms affect the dislocation core structure. Here, by exploring the hydrogen role on the dissociated edge dislocation, we reveal that there exists an additional attractive force between two partials due to the hydrogen atmosphere, which would reduce the equilibrium separation distance. This hydrogen-induced attractive force is quantitatively estimated by means of continuum mechanics. Furthermore, molecular statics simulations also capture the hydrogen-reduced separation distance under varying hydrogen background fractions, qualitatively verifying the theoretical prediction of attractive force. These findings at the atomistic scale will inform the hydrogen embrittlement modeling and experiments, especially on the hydrogen effect on the dislocation glide, climb, dynamics strain ageing, and so on. [ABSTRACT FROM AUTHOR]

Chlorophyll is an important component of crop photosynthesis as it is necessary for the material exchange between crops and the atmosphere. The amount of chlorophyll present reflects the growth and health status of crops. Spectral technology is a feasible method for obtaining crop chlorophyll content. The first-order differential spectral index contains sufficient spectral information related to the chlorophyll content and has a high chlorophyll prediction ability. Therefore, in this study, the hyperspectral index data and chlorophyll content of soybean canopy leaves at different growth stages were obtained. The first-order differential transformation of soybean canopy hyperspectral reflectance data was performed, and five indices, highly correlated with soybean chlorophyll content at each growth stage, were selected as the optimal spectral index input. Four groups of model input variables were divided according to the following four growth stages: four-node (V4), full-bloom (R2), full-fruit (R4), and seed-filling stage (R6). Three machine learning methods, support vector machine (SVM), random forest (RF), and back propagation neural network (BPNN) were used to establish an inversion model of chlorophyll content at different soybean growth stages. The model was then verified. The results showed that the correlation coefficient between the optimal spectral index and chlorophyll content of soybean was above 0.5, the R2 period correlation coefficient was above 0.7, and the R4 period correlation coefficient was above 0.8. The optimal estimation model of soybean and chlorophyll content is established through the combination of the first-order differential spectral index and RF during the R4 period. The optimal estimation model validation set determination coefficient (R2) was 0.854, the root mean square error (RMSE) was 2.627, and the mean relative error (MRE) was 4.669, demonstrating high model accuracy. The results of this study can provide a theoretical basis for monitoring the growth and health of soybean crops at different growth stages. [ABSTRACT FROM AUTHOR]

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 integrated management of water and fertilizer has been widely applied for effectively utilizing limited rainwater resources in rainfed farming systems. However, the combined effect of straw mulching and urea blended with slow-release nitrogen fertilizer (SU) on rainfed maize has seldom been studied. A two-year field experiment (2016–2017) was conducted to evaluate the effects of various agronomic practices, i.e. wheat straw mulching over the entire soil surface (QSU), wheat straw mulching over the partial soil surface (DSU), and water-retaining agent (BSU) under two N application rates (N1: 120 kg ha−1 and N2: 180 kg ha−1) on rainfed maize in northwest China. The results showed that DSUN2 delayed leaf senescence, increased chlorophyll content and photosynthesis, promoted N uptake, and increased grain yield (GY) (by 19.34%-39.91% in 2016 and 11.00%-52.57% in 2017), water use efficiency (WUE) (by 14.35%-56.21% in 2016 and 8.87%-57.44% in 2017) and nitrogen use efficiency (NUE) (by 12.03%-31.82% in 2016 and 0.49%-9.34% in 2017). More soil water was retained by QSU, which significantly promoted maize growth, but decreased GY compared with DSU. In conclusion, DSUN2 was the most effective agricultural management practice for improving GY, WUE and NUE of rained maize in northwest China. [ABSTRACT FROM AUTHOR]

Leaf area index (LAI) and above-ground biomass are both vital indicators for evaluating crop growth and development, while rapid and non-destructive estimation of crop LAI and above-ground biomass is of considerable significance for crop field management. Owing to the advantages of repeatable and high-throughput observations, spectral technology provides a feasible method for obtaining LAI and above-ground biomass of crops. In the present study, the spectral, LAI and above-ground biomass data of winter wheat were collected, and 7 species (14 in total) were calculated based on the original and first-order differential spectrum correlation spectral indices with LAI. Then, the correlation matrix method was used for correlation with LAI. The optimal wavelength combination was extracted, and the results were calculated as the optimal spectral index related to LAI. The calculation process of the optimal spectral index related to above-ground biomass was the same as that aforementioned. Finally, the optimal spectral index was divided into three groups of model input variables, winter wheat LAI and above-ground biomass estimation models were constructed using support vector machine (SVM), random forest (RF) and a back propagation neural network (BPNN), and the models were verified. The results show that the correlation coefficient between the highest of the optimal spectral indices, the LAI, and the above-ground biomass of winter wheat exceeded 0.6, and the correlation was good. The methods for establishing the optimal estimation models for LAI and above-ground biomass of winter wheat are all modeling methods in which the input variables are the combination of the first-order differential spectral index (combination 2) and RF. The R2 of the LAI estimation model validation set was 0.830, the RMSE was 0.276, and the MRE was 6.920; the R2 of the above-ground biomass estimation model validation set was 0.682, RMSE was 235.016, MRE was 4.336, and the accuracies of both models were high. The present research results can provide a theoretical basis for crop monitoring based on spectral technology and provide an application reference for the rapid estimation of crop growth parameters. [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]

Polycrystalline GdCrO3 was synthesized by the solid-state reaction method. The temperature-dependent microstructure and magnetic properties were investigated systematically. Both the Raman and FTIR spectra indicate a microstructure anomaly around 170 K. Magnetic studies demonstrate that the sample experiences two magnetic transitions around TN(Cr) ~ 167 K and TN(Gd) ~ 2.8 K related to the AFM Cr3+–Cr3+ interaction and Gd3+–Gd3+ interaction. Interestingly, the ferrimagnetic interaction between Gd and Cr ions results in the temperature-dependent magnetic reversal (TMR) together with a spin flipping (SF) that occurs at Tmin ~ 25.7 K. Due to the anisotropic exchange interaction of the Gd3+–Cr3+, a spin reorientation (SR) from Г4 (Gx, Ay, Fz) phase to Г2 (Fx, Cy, Gz) phase occurs at TSR ~ 7.8 K. In addition, a giant magnetocaloric effect (MCE) caused by the second-order AFM phase transition of Gd3+ ordering is observed at T = 3 K and H = 3 T with a magnetic entropy of − ΔSM ~ 32.8 J/kg⋅K. The present research suggests that GdCrO3 can be considered as a potential candidate material for applying in magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The online event discovery in social media based documents is useful, such as for disaster recognition and intervention. However, the diverse events incrementally identified from social media streams remain accumulated, ad hoc, and unstructured. They cannot assist users in digesting the tremendous amount of information and finding their interested events. Further, most of the existing work is challenged by jointly identifying incremental events and dynamically organizing them in an adaptive hierarchy. To address these problems, this article proposes dynamic and hierarchical Categorization Modeling (dhCM) for social media stream. Instead of manually dividing the timeframe, a multimodal event miner exploits a density estimation technique to continuously capture the temporal influence between documents and incrementally identify online events in textual, temporal, and spatial spaces. At the same time, an adaptive categorization hierarchy is formed to automatically organize the documents into proper categories at multiple levels of granularities. In a nonparametric manner, dhCM accommodates the increasing complexity of data streams with automatically growing the categorization hierarchy over adaptive growth. A sequential Monte Carlo algorithm is used for the online inference of the dhCM parameters. Extensive experiments show that dhCM outperforms the state-of-the-art models in terms of term coherence, category abstraction and specialization, hierarchical affinity, and event categorization and discovery accuracy. [ABSTRACT FROM AUTHOR]

Future quadratic programming (FQP) is an interesting and challenging topic due to its unknown future information and time-dependent feature. In this paper, a continuous-time zeroing neurodynamics (CTZN) model for quadratic programming is first obtained via zeroing neurodynamics (ZN) method. Then, a general four-step Zhang et al. discretization formula is presented and adopted to discretize the above CTZN model, and thus the general four-step discrete-time ZN (DTZN) algorithm for the FQP is developed. For comparison, a three-step DTZN algorithm and a one-step DTZN algorithm for the FQP are also presented. It is worth noting that there is an important parameter termed stepsize in the DTZN algorithms, which is closely related to their stability. If the value of stepsize is outside its effective interval, the DTZN algorithms are impossible to achieve convergence in terms of residual errors, which leads to failure of the FQP problem solving. By utilizing bilinear transformation and Routh stability criterion, the effective stepsize interval of the general four-step DTZN algorithm is confirmed via theoretical proof. Besides, numerical results substantiate the effectiveness and superiority of the general four-step DTZN algorithm as well as the accuracy of the effective stepsize interval. Finally, the general four-step DTZN algorithm is applied to fulfill the path-tracking control of different robot manipulators, with the effectiveness and superiority further validated. [ABSTRACT FROM AUTHOR]

In this article, future different-layer linear equation and bounded inequality (DLLEBI) is investigated as a new and challenging problem. The continuous bounded inequality is converted into equality by introducing a time-variant nonnegative vector. A continuous zeroing neural network (CZNN) model is proposed for solving the corresponding continuous DLLEBI by utilizing the ZNN method. Adams–Bashforth (AB) methods are combined with the CZNN model to improve the computational precision. Hence, AB discrete ZNN (AB-DZNN) models are proposed to solve future DLLEBI. Specifically, a four-step AB-DZNN model with high precision is proposed. Three-, two-, and one-step AB-DZNN models are also developed for comparative analyses. Theoretical analyses and numerical results substantiate the validity and superiority of the proposed four-step AB-DZNN model for solving future DLLEBI. In addition, motion control problems of three-link, mobile, and physical Kinova JACO $^2$ robot arms are formulated as three specific future DLLEBI problems. These problems can be solved by the four proposed AB-DZNN models. Comparative numerical results provide further evidence that the proposed four-step AB-DZNN model has the most superior computational performance among the four AB-DZNN models. [ABSTRACT FROM AUTHOR]

Because of its extensive appearance and application in scientific research and industrial production, the matrix square root problem has received massive attention and study. In this paper, based on our previous work, by using zeroing neural dynamics (ZND) method, a continuous-time dynamic matrix square root (CTDMSR) model is given at first. Besides, a general ten-instant Zhang et al. discretization (ZeaD) formula is derived, constructed and investigated, and the corresponding theoretical analysis is provided. Next, by applying this general formula to discretize the CTDMSR model, a general ten-instant discrete-time dynamic matrix square root (DTDMSR) model with sixth-order precision is further obtained. For comparison purposes, four DTDMSR models, with the second-, third-, fourth-, and fifth-order precision, are also acquired and presented, respectively, by using other ZeaD formulas. At last, the effectiveness and correctness of the proposed DTDMSR models for dynamic matrix square root finding are further substantiated by numerical experimental results. [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]

YCr0.6Fe0.4 O3sample was synthesized by sol-gel method and the microstructure and magnetic properties of Fe3 doped YCrO3 sample were investigated systematically. The XRD patterns showed that the sample presented good single-phase orthogonal structure with space group Pnma. Fourier transform infrared sectors copy (FTIR) and Raman spectra results showed the vibration modes of YCr0.6Fe0.4 O3 shifted to low wave number in comparison with YCrO3, owing to the increase of Y/Crr band lengths and lattice distortion resting from the substitution of Fe3 . M-T curves indicted that the antiferromagnetic phase transition occurred at TN = 183 K. With the decrease of temperature, the magnetization increased and a wide peak appeared at 128 K. Further cooling, the magnetization reached to minimum value 0.08 emu/g at 85 K and then increased gradually. The phenomenon was ascribed to the coexisting Cr -O² rCr3, Fe3 -O² rFe antiferromagnetic order and Fe -O² rFeferromagnetic interaction as well as the magnetization reversal caused by the Fe/Crèche cluster m Fe doped YCrO3 system. Below 80 K, the magnetic step effect was observed n M-H curves. Meanwhile, the sample also exhibited an typical exchange baas effect at T = 50 K in field cooling condition and hysteresis loops were coincident with increasing fields, suggesting the pinning effect of the antiferromagnetic phase to the ferromagnetic phase in the investigated YCr0.6Fe0.4 O3 sample. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is capable of causing a variety of chronic infections due to the formation of biofilms. Iron is essential for growth of Pseudomonas aeruginosa, and therapies that interfere with iron may help treat P. aeruginosa infections. Herein, we investigated whether artesunate, which is a type of iron-dependent drug, could influence Pseudomonas aeruginosa biofilm formation and structure, including the underlying mechanisms. Artesunate could enhance twitching motility significantly and decrease the proportion of surviving cells in Pseudomonas aeruginosa biofilms in a dose-dependent manner. Artesunate treatment also reduced biofilm thickness, diffusion in the biomass, and the content of Fe(II). However, changes in biofilm structure and ion concentration were very similar following treatment with 512 μg/ml and 1024 μg/ml artesunate. Interestingly, both biofilm structure and surviving cell fraction were recovered after iron supplementation. These results suggest that artesunate interferes with Pseudomonas aeruginosa biofilms by decreasing bacterial viability and enhancing twitching motility in an iron-independent manner. [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]

In this study, a novel tracer, horseradish peroxidase (HRP) functionalized gold nanorods (Au NRs) nanocomposites (HRP–Au NRs), was designed to label the signal antibodies for sensitive electrochemical measurement of alpha-fetoprotein (AFP). The preparation of HRP–Au NRs nanocomposites and the labeling of secondary antibody (Ab 2 ) were performed by one-pot assembly of HRP and Ab 2 on the surface of Au NRs. The immunosensor was fabricated by assembling carbon nanotubes (CNTs), Au NRs, and capture antibodies (Ab 1 ) on the glassy carbon electrode. In the presence of AFP antigen, the labels were captured on the surface of the Au NRs/CNTs via specific recognition of antigen–antibody, resulting in the signal intensity being clearly increased. Differential pulse voltammetry (DPV) was employed to record the response signal of the immunosensor in phosphate-buffered saline (PBS) containing hydrogen peroxide (H 2 O 2 ) and 3,3′,5,5′-tetramethylbenzidine (TMB). Under optimal conditions, the signal intensity was linearly related to the concentration of AFP in the range of 0.1–100 ng ml −1 , and the limit of detection was 30 pg ml −1 (at signal/noise [S/N] = 3). Furthermore, the immunoassay method was evaluated using human serum samples, and the recovery obtained was within 99.0 and 102.7%, indicating that the immunosensor has potential clinical applications. [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]

Carbon dioxide (CO2) is currently the most harmful greenhouse gas in the atmosphere. Obtaining long-term, high-resolution atmospheric column CO2 concentration (XCO2) datasets is of great practical significance for mitigating the greenhouse effect, identifying and controlling carbon emission sources, and achieving carbon cycle management. However, mainstream satellite observations provide XCO2 datasets with coarse spatial resolution, which is insufficient to support the needs of higher-precision research. To address this gap, in this study, we integrate spatial information with the extreme random trees model and develop a new machine learning model called spatial extreme random trees (SExtraTrees) to reconstruct a 1 km spatial resolution XCO2 dataset for China from 2016 to 2020. The results indicate that the predictive ability of spatial extreme random trees is more stable and has higher fitting accuracy compared to other methods. Overall, XCO2 in China shows an increasing trend year by year, with the spatial distribution revealing significantly higher XCO2 levels in eastern coastal regions compared to western inland areas. The contributions of this study are primarily in the following areas: (1) Considering the spatial heterogeneity of XCO2 and combining spatial features with the advantages of machine learning, we construct the spatial extreme random trees model, which is verified to have high predictive accuracy. (2) Using the spatial extreme random trees model, we reconstruct high-resolution XCO2 datasets for China from 2016 to 2020, providing data support for carbon emission reduction and related decision making. (3) Based on the generated dataset, we analyze the spatiotemporal distribution patterns of XCO2 in China, thereby improving emission reduction policies and sustainable development measures. [ABSTRACT FROM AUTHOR]

• Tumor cells constitute the direct targets of anti-VEGF therapy; • Tumor cells possess the capacity to independently develop resistance to VEGF inhibition; • Acquired resistance to VEGF inhibition within tumor cells is reversible. Vascular endothelial growth factor (VEGF) inhibition is an essential targeted strategy for malignant tumors, but its efficacy is severely constrained by drug resistance. The traditional view holds that the target of VEGF inhibition is endothelial cells, and thus compensatory angiogenesis is considered the main mechanism of drug resistance. In this study, we found that tumor cells themselves could develop acquired resistance to VEGF therapy, indicating an independent resistance mechanism apart from angiogenesis. Notably, this acquired resistance was temporary, disappearing completely four days after discontinuing exposure to the drug in vitro. Our findings suggest that tumor cells may also be targets of VEGF inhibition, and their response to treatment should not be overlooked in contributing to drug resistance. [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]

China has the largest apple-growing area and fresh fruit production in the world; however, water shortages and low fertilizer utilization rates have restricted agricultural development. It is a major challenge to obtain scientific and reasonable irrigation and fertilization systems for young apple trees in semi-arid regions of northern China. A 2-year field bucket experiment with four irrigation levels of W1 (75–90% Fs, where Fs is the field water holding capacity), W2 (65–80% Fs), W3 (55–70% Fs), and W4 (45–60% Fs), and three fertilizer levels of F1 (27-9-9 g N-P2O5-K2O), F2 (18-9-9 g N-P2O5-K2O), and F3 (9-9-9 g N-P2O5-K2O) was conducted in 2019 and 2020, so as to explore the effects of different water and fertilizer treatments on the growth and physiological characteristics of young apple trees. The results showed that the plant growth, leaf area, and dry matter of young apple trees at each growing period reached maximum values under F1W2, and they showed a positive linear relationship with relative chlorophyll content (SPAD), net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), water consumption, and water use efficiency (WUE). With the growth of young apple trees, water-fertilizer coupling could significantly increase the leaf SPAD of young apple trees. Pn, Tr, and Gs reached the maximum value under F1W1, and although they decreased under F1W2, the water use efficiency increased by 2.3–25.7% and 4.0–23.8% under F1W2 compared with other treatments in two years, respectively. The water consumption of young apple trees increased with the increase of irrigation and fertilizer, and both dry matter and water productivity reached the maximum value under F1W2, which increased by 0.8%, 14.6% in 2019, and 0.6%, 11.1% in 2020 compared with F1W1, while water consumption decreased by 12.2% and 9.4% in both years. In conclusion, F1W2 treatment (soil moisture was controlled at 65–80% of field water holding capacity, and N-P2O5-K2O was controlled at 27-9-9 g) was the best coupling mode of water and fertilizer for young apple trees in semi-arid areas of northern China. [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]

In this paper, a new five-step discrete-time zeroing dynamics (DTZD) algorithm, discretized from a continuous-time zeroing dynamics (CTZD) model, is proposed and investigated for online future nonlinear minimization (OFNM), i.e., online discrete-time dynamic nonlinear minimization. For approximating more accurately the first-order derivative and discretizing more effectively the CTZD model, a six-node g-cube discretization (6Ng CD) formula with higher precision is presented to obtain the new five-step DTZD algorithm. Besides, the corresponding theoretical result shows that the proposed five-step DTZD algorithm is with a quartic steady-state error pattern, i.e., O(g4) pattern, with g denoting the sampling gap. Moreover, a general DTZD algorithm is constructed by applying the general linear multistep method, and a specific DTZD algorithm based on the 4th-order Adams-Bashforth method (termed DTZD-AB algorithm for short) is further developed for OFNM. Several numerical experiments are conducted to substantiate the efficacy, accuracy, and superiority of the proposed five-step DTZD algorithm (as well as the DTZD-AB algorithm) for solving the OFNM problem, as compared with the one-step and three-step DTZD algorithms developed and investigated in previous works. [ABSTRACT FROM AUTHOR]

This paper focuses on the formation encirclement problem of multiple quadrotors subjected to semi‐Markov jump switching topologies under consensus strategy. A target encirclement control algorithm is designed to achieve an enclosed formation, which drives autonomous quadrotors around the target so the target can't get away. Afterward, we propose a decentralized consensus‐based control protocol to realize the encirclement of the target quadrotor, where onboard miniature computers carry out all necessary computations. Notably, the quadrotor is modeled by a double integrator and the switching topology is described by a signed graph subjected to the semi‐Markov jump process. Whereafter, some criteria in the form of linear matrix inequalities are constructed based on the Lyapunov stability theory to achieve encirclement behavior. Ultimately, the proposed approach is verified by a comparison simulation and two flight experiments with three follower quadrotors enclosing a leader quadrotor. [ABSTRACT FROM AUTHOR]

The cultivation of Panax notoginseng has been plagued by a multitude of challenges, including recurrent diseases, suboptimal value, inadequate quality, and environmental degradation resulting from improper water and fertilizer management. To address these issues and improve the yield of P. notoginseng and its saponin content, this study endeavors to identify the optimal irrigation and fertilization levels in shaded environments in Yunnan Province in Southwest China. In this field experiment, three-year-old plants were tested to evaluate the effects of water, soluble organic fertilizers, and their combinations on plant growth, physiological parameters, yield, and saponin content. The experiment included 12 treatments with three types of irrigation (10 (W1), 15 (W2), and 20 (W3) mm), totaling 440, 660, and 880 mm, and four levels of the total amount of fertilization (F1 (60, total N 12.6, total P 5.5, and total K 10.5 kg ha−1), F2 (90, total N 18.9, total P 8.3, and total K 15.7 kg ha−1), F3 (120, total N 25.2, total P 11.0, and total K 20.9 kg ha−1), F4 (150, total N 31.5, total P 13.8, and total K 26.1 kg ha−1)). The randomized complete block design was used, with 36 plots in total and 3 replications. The study utilized the TOPSIS method to determine the most effective water and fertilizer management strategy for the growth and production of P. notoginseng. The assessment of yield, water and fertilizer productivity, and saponin content across all treatments revealed that the W3F3 treatment resulted in significant increases in the plant's height, stem diameter, and net photosynthetic rate. Meanwhile, the W2F3 treatment exhibited the best root morphological traits. The W3F4 treatment effectively increased dry matter and transpiration. The combination of water and fertilization had a coupling effect that not only increased yield to 1400 kg ha−1 but also improved water–fertilizer productivity. The application of the W2F3 treatment resulted in a significant increase in the accumulation of active components, leading to a total P. notoginseng saponin (PNS) content of 24.94%. Moreover, the comprehensive index obtained through the TOPSIS model indicated that the W2F3 treatment outperformed other treatments. Therefore, this treatment can be considered a promising water and fertilizer model for P. notoginseng cultivation, which can enhance its yield, quality, and productivity while promoting sustainable green development. [ABSTRACT FROM AUTHOR]

Excessive use of chemical fertilizers deteriorates the soil environment and limits the normal growth of Arabica coffee trees. In order to identify the optimal coupling mode of chemical fertilizer application and biomass return that enhances the soil ecological environment and promotes the photosynthetic efficiency of Arabica coffee, this study investigated the impacts of three levels of inorganic fertilizers (FL: 360 kg·ha−1, FM: 720 kg·ha−1, and FH: 1080 kg·ha−1) and three types of coffee husk returning methods (CB: coffee husk biochar, CC: coffee husk compost, CA: coffee husk ash) on the soil fertility, microbial amount, enzyme activity, and photosynthetic characteristics of the Arabica coffee root zone. The entropy weight-TOPSIS method was employed to evaluate the comprehensive benefits. The results showed that FM had the biggest effect on improving soil fertility, microorganisms, and enzyme activities compared with FL and FH. Moreover, compared to CA, CC significantly increased soil organic carbon, organic matter, and total nitrogen content. CC significantly enhanced the activities of soil phosphatase and urease, respectively, by 29.84% and 96.00%, and significantly increased the amount of bacteria, fungi, and actinomycetes by 62.15%, 68.42%, and 46.21%, respectively. The net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) of FMCC were significantly higher than those of other treatments. The comprehensive benefit evaluation of the soil environment and photosynthetic characteristics by the entropy weight-TOPSIS method ranked FMCC first. Therefore, FMCC was the optimal coupling mode for fertilizer application and the coffee husk returning method. The findings of this study not only provide scientific guidance for fertilizing Arabica coffee but also clarify the proper approach to returning coffee husk to the field, thereby improving soil ecology and promoting green and efficient production of specialty crops. [ABSTRACT FROM AUTHOR]

In this study, a sandwich-type electrochemical immunosensor for the detection of C-reactive protein (CRP) is described. In design, Copper nanoparticles (Cu NPs) were used for signal tag and hybridization chain reaction (HCR)amplified output signal. The immunosensor fabrication involved three steps: (i) primary antibodies (Ab 1 ) were immobilized on the surface of gold nanoparticles (Au NPs); (ii) the sandwich-type structure formation contained “primary antibodies-antigen-secondary antibodies conjugated with primer (Ab 2 -S 0 )”; and (iii) long DNA concatemers intercalating amounts of Cu NPs was linked to the sandwich-type structure via hybridization reaction. Differential pulse voltammetry (DPV) was used to record the response signal of the immunosensor in phosphate-buffered saline (PBS). Under optimal conditions, the anodic peak currents of Cu NPs at the peak potential of about 0.08V(VS.SCE) were linear with the logarithm of CRP concentration in the range of 1.0 fg mL −1 to 100 ng mL −1 with a detection limit of 0.33 fg mL −1 (at signal/noise [S/N] = 3). In addition, the practical application of immunosensor was evaluated by analyzing CRP in real human serum samples, the recoveries obtained were within 95.3%–103.8%, indicating the immunosensor possessed potential application ability for practical disease diagnosis. [ABSTRACT FROM AUTHOR]

Affected by global warming, the frequency of crop pests and diseases have increased, causing huge losses to agricultural production. To better grasp the development and trends of research on the effects of climate change on crop pests and diseases, the literature on the impact of climate change on crop pests and diseases published from 1990 to 2021 in the Web of Science (WOS) core collection database was used. This study explores the literature characteristics and hotspot evolution through the bibliometric visualization analysis software COOC, VOSviewer, and CiteSpace, with a view to identifying the changing characteristics and trends of research changes in this field. The results showed that the number of literature on the impact of climate change on crop pests and diseases increased rapidly. The main fields involved include environmental sciences, ecology, and agronomy. Papers in these fields mainly published in journals, such as PLos One, Forest Ecology and Management, and Frontiers in Plant Science. The country with the highest number of publications was the United States, followed by China and Australia. The most prolific authors in the top 20 are research scholars from China. The first author of the top 20 highly cited papers was from the United States. It was found that that current research on the impact of climate change on crop pests and diseases mainly focuses on agricultural production and food safety. Modelling and crop growth has maintained steady development. At present, research in this field mainly focuses on pest management strategies under the impact of climate change, the response of single species, and the complex ecological mechanisms behind the response. This study provides unique insights into the research field of the impact of climate change on crop pests and diseases and provides a reference direction for future research development in this field. [ABSTRACT FROM AUTHOR]

In dryland agriculture, mulching methods and nitrogen application have been extensively adopted to improve water and nitrogen use efficiency and increase crop yield. However, there has been a scarcity of research on the combined effects of mulching types and nitrogen application on the growth and yield of soybean (Glycine max L.). In the present study, four nitrogen levels (N0: 0 kg N ha−1, N1: 60 kg N ha−1, N2: 120 kg N ha−1, N3: 180 kg N ha−1) and four mulching methods (NM: no mulching, SM: straw mulching, FM: film mulching, SFM: straw and film mulching) were set so as to evaluate the effects of mulching methods and nitrogen application on dry matter accumulation, grain yield, water-nitrogen use efficiency, and economic benefits of soybean in Northwest China from 2021 to 2022. The results show that the dry matter accumulation, yield formation, water and nitrogen use efficiency, and economic benefits of soybean were improved under different mulching methods (SM, FM, and SFM) and nitrogen applications (N1-N3), and that the effect is the best when the nitrogen application rate is N2 and the mulching method is FM. As such, a conclusion could be drawn that suitable nitrogen application (120 kg ha−1) combined with film mulching was beneficial for the utilization of rainwater resources and soybean production in the dryland of Northwest China. [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]

The processivity factor of the human cytomegalovirus (HCMV) DNA polymerase phosphoprotein ppUL44 plays an essential role in viral replication, showing nuclear localization in infected cells. The present study examines ppUL44's nuclear import pathway for the first time, ectopic expression of ppUL44 revealing a strong nuclear localization in transfected COS-7 and other cell types, implying that no other HCMV proteins are required for nuclear transportation and retention. We show that of the two potential nuclear localization signals (NLSs) located at amino acids 162–168 (NLS1) and 425–431 (NLS2), NLS2 is necessary and sufficient to confer nuclear localization. Moreover, using enzyme-linked immunosorbent assays and gel mobility shift assays, we show that NLS2 is recognized with high affinity by the importin (IMP) α/β heterodimer. Using gel mobility shift and transient transfection assays, we find that flanking sequences containing a cluster of potential phosphorylation sites, including a consensus site for protein kinase CK2 (CK2) at Ser413 upstream of the NLS, increase NLS2-dependent IMP binding and nuclear localization, suggesting a role for these sites in enhancing UL44 nuclear transport. Results from site-directed mutagenic analysis and live-cell imaging of green fluorescent protein (GFP)-UL44 fusion protein-expressing cells treated with the CK2-specific inhibitor 4,5,6,7-tetrabromobenzotriazole are consistent with phosphorylation of Ser413 enhancing ppUL44 nuclear transport. [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]

BACKGROUND Sustainable greenhouse tomato production requires optimal fertilizer management to achieve the double‐win strategy of producing high yields and maximizing profits with less environmental pollution. The objective of this study was to seek an optimal fertilization strategy maintaining high productivity of greenhouse tomato, improving nitrogen use efficiency and reducing nitrate leaching risk. RESULTS: The combined application of soluble organic and chemical fertilizers for topdressing (SOSC) not only produced more fruit yield (75.18 Mg ha−1) and plant dry matter (10 449.12 kg ha−1), but also enhanced plant nutrients uptake, nitrogen recovery efficiency (39.22%), nitrogen agronomic efficiency (176.78 kg kg−1), soluble solids, vitamin C and lycopene content in tomato fruits compared with the other treatments, that is chicken manures for basal application and chemical fertilizer for topdressing (CC), soluble organic fertilizer for topdressing (SO) and soluble chemical fertilizer for topdressing (SC). In terms of soil nutrients residue, SOSC had no obvious NO3−‐N accumulation area in the 0–60 cm soil layer, unlike large accumulation in the soil layer below 30 cm in SO and SC. CONCLUSION: The combined application of soluble organic and chemical fertilizers is highly recommended to sustain fruit yield, improve nitrogen use efficiency and reduce soil degradation risks in commercial greenhouse tomato production. [ABSTRACT FROM AUTHOR]

Background Few studies have compared the yield of reverse transcription polymerase chain reaction (RT-PCR) assays in nasopharyngeal swabs, oropharyngeal swabs, and sputum for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection. Methods We conducted an observational study in Beijing Ditan Hospital, China. Specimens including nasopharyngeal swabs, oropharyngeal swabs, and sputum from confirmed coronavirus 2019 patients were collected for RT-PCR testing. Disease duration was calculated from the date of symptom onset to the date of specimen collection and divided into 3 groups: ≤14 days, 14–21 days, and >21 days. We compared positive rates across the 3 specimens collected. The kappa coefficient was used to evaluate the consistency of RT-PCR results between different specimens. Results A total of 291 specimens were collected and tested from 43 confirmed patients. Among specimens collected with a disease duration of ≤14 days, the positive rate was highest in sputum (79.2%); this rate was significantly higher than that in nasopharyngeal swabs (37.5%; P =.003) and oropharyngeal swabs (20.8%; P <.001). Similar findings were observed with the disease durations of 14–21 days and >21 days. The consistency of testing results between nasopharyngeal swabs and oropharyngeal swabs was low with the disease durations of ≤14 days and >21 days. The consistency between the sputum and oropharyngeal swabs and between the sputum and nasopharyngeal swabs was very low across all 3 disease durations, with statistical significance. Conclusions Compared with nasopharyngeal swabs and oropharyngeal swabs, sputum had the highest yield of SARS-CoV-2 detection. Nasopharyngeal swabs and oropharyngeal swabs had a similar yield. If sputum is not feasible, a nasopharyngeal swab can be recommended for the detection of SARS-CoV-2, and early testing is needed. [ABSTRACT FROM AUTHOR]

The Ca3CoMn1-xTixO6(x = 0, 0.05) samples were synthesized by a modified sol-gel method, and the microstructure, microtopography, and magnetic properties were investigated in detail. With substituting of Mn4+ ions by Ti4+ ions, the crystallinity and particle size of Ca3CoMn1-xTixO6 (x = 0, 0.05) samples decrease. The Ti4+ doping also causes the high-temperature spin freezing phenomenon disappears, and the transition field of ↑↑↓↓ magnetic structure to ↑↑↑↓ magnetic structure increases obviously together with the faster dynamic behavior. These results suggest that the dilution effect of Ti4+ doping to Co-Mn-Co-Mn spin chains could reduce the degree of magnetic frustration and suppress the formation of short range magnetic order, for which will be beneficial for the establishment of more robust long range antiferromagnetic structure. The present research could serve as a reference on tuning the magnetic order and improving the multiferroic property of Ca3CoMnO6. [ABSTRACT FROM AUTHOR]