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This study systematically investigated the physiological and molecular responses of the wheat mutant 'XC-MU201' under high-temperature stress through comprehensive transcriptome analysis and physiological measurements. RNA sequencing of 21 samples across seven different treatment groups revealed, through Weighted Gene Co-expression Network Analysis (WGCNA), 13 modules among 9071 genes closely related to high-temperature treatments. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed significant enrichment of lignin biosynthesis-related modules under high-temperature conditions, especially at the H-10DAT, H-20DAT, and H-30DAT time points. Experimental results demonstrated a significant increase in lignin content in high-temperature-treated samples, confirmed by tissue staining methods, indicating wheat's adaptation to heat damage through lignin accumulation. The phenylalanine ammonia-lyase gene (TaPAL33) was significantly upregulated under high-temperature stress, peaking at H-30DAT, suggesting its critical role in cellular defense mechanisms. Overexpression of TaPAL33 in the wheat variety 'Xinchun 11' enhanced lignin synthesis but inhibited growth. Subcellular localization of GFP-labeled TaPAL33 in tobacco cells showed its distribution mainly in the cytoplasm and cell membrane. Transgenic wheat exhibited higher PAL enzyme activity, enhanced antioxidant defense, and reduced oxidative damage under high-temperature stress, outperforming wild-type wheat. These results highlight TaPAL33's key role in improving wheat heat tolerance and provide a genetic foundation for future research and applications. [ABSTRACT FROM AUTHOR]

Citrus is the largest fruit crop around the world, while high nitrogen (N) application in citrus orchards is widespread in many countries, which results not only in yield, quality and environmental issues but also slows down the establishment of citrus canopies in newly cultivated orchards. Thus, the objective of this study was to investigate the physiological inhibitory mechanism of excessive N application on the growth of citrus seedlings. A pot experiment with the citrus variety Orah (Orah/Citrus junos) at four N fertilization rates (0, 50, 100, and 400 mg N/kg dry soil, denoted as N0, N50, N100, and N400, respectively) was performed to evaluate the changes of root morphology, biomass, N accumulation, enzyme activities, and so on. The results showed that the N400 application significantly reduced the total biomass (from 14.24 to 6.95 g/Plant), N accumulation (from 0.65 to 0.33 g/Plant) and N use efficiency (92.69%) in citrus seedlings when compared to the N100 treatment. The partial least squares pathway model further showed that the decline of biomass and N accumulation by high N application were largely attributed to the reduction of root growth through direct and indirect effects (the goodness of fit under the model was 0.733.) rather than just soil N transformation and activity of root N uptake. These results are useful to optimize N management through a synergistic N absorption and utilization by citrus seedlings. [ABSTRACT FROM AUTHOR]

Drought-induced stress poses a significant challenge to wheat throughout its growth, underscoring the importance of identifying drought-stable quantitative trait loci (QTLs) for enhancing grain yield. Here, we evaluated 18 yield-related agronomic and physiological traits, along with their drought tolerance indices, in a recombinant inbred line population derived from the XC7 × XC21 cross. These evaluations were conducted under both non-stress and drought-stress conditions. Drought stress significantly reduced grain weight per spike and grain yield per plot. Genotyping the recombinant inbred line population using the wheat 90K single nucleotide polymorphism array resulted in the identification of 131 QTLs associated with the 18 traits. Drought stress also exerted negative impacts on grain formation and filling, directly leading to reductions in grain weight per spike and grain yield per plot. Among the identified QTLs, 43 were specifically associated with drought tolerance across the 18 traits, with 6 showing direct linkages to drought tolerance in wheat. These results provide valuable insights into the genetic mechanisms governing wheat growth and development, as well as the traits contributing to the drought tolerance index. Moreover, they serve as a theoretical foundation for the development of new wheat cultivars having exceptional drought tolerance and high yield potentials under both drought-prone and drought-free conditions. [ABSTRACT FROM AUTHOR]

The growth of fruit trees depends on the nitrogen (N) remobilization in mature tissues and N acquisition from the soil. However, in evergreen mature citrus (Citrus reticulata Blanco) leaves, proteins with N storage functions and hub molecules involved in driving N remobilization remain largely unknown. Here, we combined proteome and physiological analyses to characterize the spatiotemporal mechanisms of growth of new leaves and storage protein degradation in mature leaves of citrus trees exposed to low-N and high-N fertilization in the field. Results show that the growth of new leaves is driven by remobilization of stored reserves, rather than N uptake by the roots. In this context, proline and arginine in mature leaves acted as N sources supporting the growth of new leaves in spring. Time-series analyses with gel electrophoresis and proteome analysis indicated that the mature autumn shoot leaves are probably the sites of storage protein synthesis, while the aspartic endopeptidase protein is related to the degradation of storage proteins in mature citrus leaves. Furthermore, bioinformatic analysis based on protein–protein interactions indicated that glutamate synthetase and ATP-citrate synthetase are hub proteins in N remobilization from mature citrus leaves. These results provide strong physiological data for seasonal optimization of N fertilizer application in citrus orchards. [ABSTRACT FROM AUTHOR]

Purpose: This research is expected to shed light on soil contamination in citrus orchards and provide a reference for soil quality maintenance and improvement in orchards under the organic fertilizer substitution scenario. Materials and methods: Heavy metals (HMs) and veterinary antibiotics (VAs) in soils collected from citrus orchards in Meishan, Sichuan Province, China, were measured. Single factor index, potential ecological risk factor, and potential ecological risk index were employed to assess the contamination status and potential ecological risks of HMs in soils. Additionally, the risk of VAs was also evaluated based on their risk quotient values. Furthermore, Pearson's correlation analysis, hierarchical cluster analysis, and principal component analysis were employed to identify the potential sources of HMs and VAs in soils. Results and discussion: HMs and VAs exhibited great variance in the study area. Nickel (Ni) was the primary metallic contaminant, followed by cadmium (Cd), chromium (Cr), and arsenic (As). HMs accumulation in soils would not pose risks to the ecosystem. Atmospheric deposition and livestock manure could be the primary sources of HMs in soils. In terms of VAs, fluoroquinolones (FQs), sulfonamides (SAs), and tetracyclines (TCs) were the major VAs in soils, with the accumulative level averaged at 84.6 μg kg−1 (36.8–369 μg kg−1). Additionally, the residual VAs, except for enrofloxacin (ENR), would only pose limited to moderated risk to soil microbes or aqueous organisms. Conclusions: Clean and high-quality organic fertilizers, instead of livestock manure, were recommended to eliminate the potential environmental risks during organic fertilizer substitution. [ABSTRACT FROM AUTHOR]

Drought stress is one of the major abiotic stresses to wheat worldwide, with negative effects on wheat growth and yield. Assessing genetic variation and drought stress tolerance of key agronomic and physiological traits of spring wheat and screening germplasm resources for higher drought tolerance and yield stability are a prerequisite for developing new, better-adapted spring wheat varieties. This study evaluated nine important agronomic and physiological traits in 152 spring wheat cultivars under non-stress (NS) and drought-stress (DS) conditions. Under DS conditions, grain yield per plot (GYP) and grain weight per spike (GWE) were significantly reduced by 33.8% and 31.7%, and their drought-tolerance indexes (DIs) were only 0.66 and 0.69, respectively, indicating that GYP and GWE are the most susceptible traits to drought stress. The SPAD value of flag leave at flowering stage decreased by 13.9% under DS conditions, and the DI of SPAD was 0.86. In addition, DI-SPAD was significantly positively correlated with DIs of plant height (PH), grain number per spikelet (GPS), grain number per spike (GNS), GWE and GYP, indicating that the drought tolerance and yield of wheat are closely related to chlorophyll retention. Six wheat germplasm accessions were identified for their ability to sustain grain yield and improve drought tolerance simultaneously. These results provide insights into the genetic co-variation between grain yield and drought stress tolerance and provide a theoretical basis for the development of new wheat cultivars with excellent drought tolerance and high yields in the presence and absence of drought. [ABSTRACT FROM AUTHOR]

This paper proposes a vision monitoring system for multipoint deflection of a large‐span bridge that can well compensate the camera motion–induced errors. The camera network system (CNS) consists of a series of dual‐camera stations that are linked with the cooperative markers. The infrared illumination supplement device is integrated in the camera station and the regular double‐sided prism is selected as the cooperative marker to realize 24‐h continuous monitoring. The feasibility and efficiency of CNS are verified by conducting a field test inside the steel box girders of a suspension bridge with a length of 1038 m. The results show that the proposed camera networking method can well solve the problem of the large‐scale high‐precision monitoring under unstable measuring platform. For the kilometer‐level flexible bridge, CNS can meet submillimeter precision in quasi‐static measurement, and can also provide deflection data similar to the conventional robotic total station and connecting pipe system in long‐term monitoring. The geometric alignment of large‐span bridges with dense multimeasuring points can be automatically monitored and recorded by CNS. The observed deflections of the studied suspension bridge are dominated with the vehicle load and wind load in the short term and are correlated with the temperature change in the long term. The proposed CNS can provide a new option for the bridge deflection monitoring and provide new parameters for bridge safety evaluation. [ABSTRACT FROM AUTHOR]

The accurate and efficient segmentation of large-scale urban point clouds is crucial for many higher-level tasks, such as boundary line extraction, point cloud registration, and deformation measurement. In this paper, we propose a novel supervoxel segmentation approach to address the problem of under-segmentation in local regions of point clouds at various resolutions. Our approach introduces distance constraints from boundary points to supervoxel planes in the merging stage to enhance boundary segmentation accuracy between non-coplanar supervoxels. Additionally, supervoxels with roughness above a threshold are re-segmented using random sample consensus (RANSAC) to address multi-planar coupling within local areas of the point clouds. We tested the proposed method on two publicly available large-scale point cloud datasets. The results show that the new method outperforms two classical methods in terms of boundary recall, under-segmentation error, and average entropy in urban scenes. [ABSTRACT FROM AUTHOR]

In this work, a non‐overlapping field of view (FOV) multi‐camera system (MCS) has been proposed to realize the motion self‐compensation, which can be flexibly arranged according to the field situation. The challenges of ensuring a complete fixed measurement platform owing to the self‐weight, unexpected collisions, and adjacent engineering constructions have been addressed in this study. MCS can be fixed on an unstable platform and employ two or more correcting cameras, without an overlapping FOV, to measure and compensate the six degrees of freedom (6‐DOF) ego‐motion of the platform, with high accuracy. The numerical simulation results show that, under the same configuration conditions, the 6‐DOF motion estimation accuracy of the proposed method is better than that of the Perspective‐n‐Points methods, especially for the estimation accuracy of the out‐of‐plane motion and the roll motion of the camera. The field demonstration has been performed on a suspension bridge, and the results demonstrate that the deflection measurements provided by the proposed MCS are consistent with those provided by the Robotic Total Station. The proposed MCS, which is not restrained by a strictly stable platform, proves to be an effective method to compensate for the errors induced by the platform ego‐motion, and it can meet the requirements of the displacement measurement of large structures needing high precision. [ABSTRACT FROM AUTHOR]

Appropriate nitrogen (N) fertilization in vegetable-maize rotations is effective in improving agricultural production and mitigating environmental impacts to ensure sustainable food security. The dynamic and sustainability of crop yields, crop root biomasses, and accumulations and sequestration rates of soil organic C (SOC) and total N (STN) were explored and analyzed under four N application rates (kg N ha−1 year−1): 0 (Control), 285 (Low-N), 480 (Medium-N), and 720 (High-N). The Low-N and Medium-N applications increased Chinese cabbage yield by 22% and 20.7% than the High-N application, respectively. The Medium-N application gained the highest grain yield and root biomass in the maize season when compared with the Low-N application. The sustainable yield index had no difference between Low-N and Medium-N treatments in Chinese cabbage-maize rotation. Compared to the Low-N application, the Medium-N application improved the storage and sequestration rates of SOC and STN. Simultaneously, the Medium-N application significantly enhanced the soil C:N ratio than the High-N application. In conclusion, the Medium-N application is a promising fertilization strategy in the Chinese cabbage-maize cropping system as it increases the yield and root biomass of crops, improves the accumulation and sequestration rates of SOC and STN, and maintains a high soil C:N ratio. [ABSTRACT FROM AUTHOR]

Online monitoring of laser welding depth is increasingly important, with the growing demand for the precise welding depth in the field of power battery manufacturing for new energy vehicles. The indirect methods of welding depth measurement based on optical radiation, visual image and acoustic signals in the process zone have low accuracy in the continuous monitoring. Optical coherence tomography (OCT) provides a direct welding depth measurement during laser welding and shows high achievable accuracy in continuous monitoring. Statistical evaluation approach accurately extracts the welding depth from OCT data but suffers from complexity in noise removal. In this paper, an efficient method coupled DBSCAN (Density-Based Spatial Clustering of Application with Noise) and percentile filter for laser welding depth determination was proposed. The noise of the OCT data were viewed as outliers and detected by DBSCAN. After eliminating the noise, the percentile filter was used to extract the welding depth. By comparing the welding depth determined by this approach and the actual weld depth of longitudinal cross section, an average error of less than 5% was obtained. The precise laser welding depth can be efficiently achieved by the method. [ABSTRACT FROM AUTHOR]

It is known that a lot of uncertainties are involved in geotechnical design of energy piles. In this paper, a Bayesian updating framework is presented to characterize those uncertainties. The load-transfer model is developed to predict the thermomechanical response of energy piles. Considering the cross-case variability of the uncertainty in the axial strains of pile, the global model bias is firstly calibrated by establishing a comprehensive database consisting of 12 energy pile cases. Furthermore, the uncertainty in input parameters is considered in the Bayesian updating of model bias in a specific case. The variability of the uncertain parameters is effectively reduced after updating. The coefficient of variation of prediction is decreased from 0.34 to 0.13. The present framework can well quantify uncertain factors and improve the accuracy and reliability of the prediction model. [ABSTRACT FROM AUTHOR]

Energy piles have been popular globally with functions of both pile foundation and ground source heat pumps. Although several researches have been devoted to the probabilistic design and assessment of energy piles, the corresponding procedures are too complicated for engineers. As a simple variant of the reliability-based design method, the load and resistance factor design (LRFD) approach for the geotechnical design of energy piles is presented in this study. Firstly, the load-transfer model for energy piles is developed to investigate the effect of cyclic thermal loading on the pile settlement. Then, the LRFD procedures based on first-order reliability method and target reliability method are implemented into two different constrained nonlinear optimization problems, respectively. The proposed LRFD model for energy piles is demonstrated through an example pile and a series of parametric analyses. [ABSTRACT FROM AUTHOR]

Nitrogen (N) remobilization is an important physiological process that supports the growth and development of trees. However, in evergreen broad-leaved tree species, such as citrus, the mechanisms of N remobilization are not completely understood. Therefore, we quantified the potential of N remobilization from senescing leaves of spring shoots to mature leaves of autumn shoots of citrus trees under different soil N availabilities and further explored the underlying N metabolism characteristics by physiological, proteome and gene expression analyses. Citrus exposed to low N had an approximately 38% N remobilization efficiency (NRE), whereas citrus exposed to high N had an NRE efficiency of only 4.8%. Integrated physiological, proteomic and gene expression analyses showed that photosynthesis, N and carbohydrate metabolism interact with N remobilization. The improvement of N metabolism and photosynthesis, the accumulation of proline and arginine, and delayed degradation of storage protein in senescing leaves are the result of sufficient N supply and low N remobilization. Proteome further showed that energy generation proteins and glutamate synthase were hub proteins affecting N remobilization. In addition, N requirement of mature leaves is likely met by soil supply at high N nutrition, thereby resulting in low N remobilization. These results provide insight into N remobilization mechanisms of citrus that are of significance for N fertilizer management in orchards. [ABSTRACT FROM AUTHOR]

This paper uses extreme value theory and exponential generalised autoregressive score models to estimate the tail extremes of financial return series. The peak-over-threshold method based on the generalised pareto distribution is combined with the EGAS models and the nonparametric quantile method is used to determine the thresholds in the POT method, which is used to calculate the value-at-risk of financial markets and to perform backtesting. The empirical analysis was conducted on the soybean oil, rapeseed oil, and palm oil futures indices in the Chinese futures market. The study demonstrated that the EGAS-POT models based on nonparametric quantile thresholds can effectively characterise tail risk and provide a feasible measure of risk for investors. [ABSTRACT FROM AUTHOR]

The quantification of soil organic carbon (SOC) and N fractions under the influence of long-term fertilisation is useful to understand soil organic matter (SOM) stabilization mechanism and to develop optimal management practices. This study was to investigate the responses of different SOC and N fractions to long-term fertilisation and their contributions to the total change in the bulk soil under a rice-wheat cropping system. Compared with soil with no fertilisation, the 22-year fertilisation improved the C and N content of the bulk soil and different fractions with the greatest increase in NPK fertilisers and rice straw treatment. The SOC and N changes of heavy fraction accounted for 92% and 88% of the total SOC increases, while the Fe/Al-bound organic carbon and humic organic carbon in heavy fraction accounted for 43% and 48%, respectively. The SOC and N contents of each fraction were positively correlated with the bulk soil and the others. It is concluded that the NPK fertilisers plus straw returning was efficient to enhance SOC and N accumulation; the chemical binding of Fe and Al in organic-mineral complexes and the further formation of recalcitrant humin might be the potential mechanism for SOM accumulation in the rice-wheat cropping system. Abbreviations: SOM: soil organic matter; SOC: soil organic carbon; STN: soil total nitrogen; POM: particulate organic matter; MOM: mineral associated organic matter; LF: light fraction; HF: heavy fraction; Ca-OC: Ca-bound organic carbon; Fe/Al-OC: Fe- or Al-bound organic carbon; Humin-OC: humic organic carbon [ABSTRACT FROM AUTHOR]

Widespread malnutrition of zinc (Zn), iodine (I), iron (Fe) and selenium (Se), known as hidden hunger, represents a predominant cause of several health complications in human populations where rice (Oryza sativa L.) is the major staple food. Therefore, increasing concentrations of these micronutrients in rice grain represents a sustainable solution to hidden hunger. This study aimed at enhancing concentration of Zn, I, Fe and Se in rice grains by agronomic biofortification. We evaluated effects of foliar application of Zn, I, Fe and Se on grain yield and grain concentration of these micronutrients in rice grown at 21 field sites during 2015 to 2017 in Brazil, China, India, Pakistan and Thailand. Experimental treatments were: (i) local control (LC); (ii) foliar Zn; (iii) foliar I; and (iv) foliar micronutrient cocktail (i.e., Zn + I + Fe + Se). Foliar-applied Zn, I, Fe or Se did not affect rice grain yield. However, brown rice Zn increased with foliar Zn and micronutrient cocktail treatments at all except three field sites. On average, brown rice Zn increased from 21.4 mg kg–1 to 28.1 mg kg–1 with the application of Zn alone and to 26.8 mg kg–1 with the micronutrient cocktail solution. Brown rice I showed particular enhancements and increased from 11 μg kg–1 to 204 μg kg–1 with the application of I alone and to 181 μg kg–1 with the cocktail. Grain Se also responded very positively to foliar spray of micronutrients and increased from 95 to 380 μg kg–1. By contrast, grain Fe was increased by the same cocktail spray at only two sites. There was no relationship between soil extractable concentrations of these micronutrients with their grain concentrations. The results demonstrate that irrespective of the rice cultivars used and the diverse soil conditions existing in five major rice-producing countries, the foliar application of the micronutrient cocktail solution was highly effective in increasing grain Zn, I and Se. Adoption of this agronomic practice in the target countries would contribute significantly to the daily micronutrient intake and alleviation of micronutrient malnutrition in human populations. [ABSTRACT FROM AUTHOR]

This study aims to determine the role of knowledge searching on creativity in the fields of science research and technology development. Creativity is a process of knowledge combination, thus internal and external knowledge searching is important for creativity in both fields, particularly in the open innovation age. However, the nature of the work across these fields is different. While science research aims to solve theoretical problems and generate new knowledge, technology development aims to apply new knowledge to solve practical problems. Compared to science research, technology development has clear task goals, which make it easier to identify the related external knowledge and integrate this knowledge and in turn improve employee creativity. Thus, employees' attention to external knowledge as well as the influence of external knowledge on creativity might be different in the two fields. Results based on an empirical study of 211 employees from science research and 257 employees from technology development showed that external knowledge searching increased employee creativity in the field of technology development but not in science research. Furthermore, employees' centrality in the intra‐team problem‐solving network moderated the relationship between external knowledge searching and creativity in the science research field. Suggestions about employee creativity management in science and technology fields are discussed. [ABSTRACT FROM AUTHOR]

The potential for nitrate leaching in Chinese vegetable systems is substantial because of high inputs of nitrogen (N) fertilizer and water. To quantify the nitrate leaching and identify the key controlling factors in Chinese vegetable systems, we conducted a meta-analysis that included 221 data sets from 18 field studies. The results revealed that nitrate leaching over the entire crop growing season in Chinese vegetable systems was very high and averaged 79.1 kg N ha−1 and primarily resulted from extremely high N fertilizer inputs (in average 423 kg N ha−1). Nitrate leaching was, on the average, 63.9% greater in the greenhouse systems (98.0 kg N ha−1) than in open-field systems (59.8 kg N ha−1). The leaching factor, defined as the proportion of the quantity of N applied to soils that was lost due to nitrate leaching, averaged 14.6% overall and was significantly lower in greenhouse systems (10.9%) than in open-field systems (18.4%). This difference appears to be due to lower of the total water inputs (irrigation + precipitation) in greenhouse systems. Nitrate leaching increased with water input, the number of growing days, and the N rate. The nitrate leaching response to increasing N rate was linear. The leaching factor significantly increased with water input but was not affected by the N rate or the number of growing days. Compared with application of synthetic fertilizer alone, the application of manure alone or manure plus synthetic fertilizer significantly reduced both the nitrate leaching and the leaching factor in open-field and greenhouse systems. These results suggest that nitrate leaching in Chinese vegetable systems can be reduced by optimizing rates of N and water supply to synchronize crop needs. Application of mixed synthetic N fertilizer and manure is more effective in reducing nitrate leaching, compared to synthetic N only. [ABSTRACT FROM AUTHOR]

The maintenance and accumulation of soil organic carbon (SOC) in agricultural systems is critical to food security and climate change, but information about the dynamic trend and efficiency of SOC sequestration is still limited, particularly under long-term fertilizations. In a typical Purpli-Udic Cambosols soil under subtropical monsoon climate in southwestern China this study thus estimated the dynamic, trend and efficiency of SOC sequestration after 22-year (1991-2013) long-term inorganic and/or organic fertilizations. Nine fertilizations under a rice-wheat system were examined: control (no fertilization), N, NP, NK, PK, NPK, NPKM (NPK plus manure), NPKS (NPK plus straw), and 1.5NPKS (150% NPK plus straw). Averagely, after 22-years SOC contents were significantly increased by 4.2-25.3% and 10.2-32.5% under these fertilizations than under control conditions with the greatest increase under NPKS. The simulation of SOC dynamic change with an exponential growth equation to maximum over the whole fertilization period predicted the SOC level in a steady state as 18.1 g kg−1 for NPKS, 17.4 g kg−1 for 1.5NPKS, and 14.5-14.9 g kg−1 for NK, NP, NPK, and NPKM, respectively. Either inorganic, organic or their combined fertilization significantly increased crop productivity and C inputs that were incorporated into soil ranging from 0.91 to 4.63 t (ha · y)−1. The C sequestration efficiency was lower under NPKM, NPKS, and 1.5NPKS (13.2%, 9.0%, and 10.1%) than under NP and NPK (17.0% and 14.4%). The increase of SOC was asymptotical to a maximum with increasing C inputs that were variedly enhanced by different fertilizations, indicating an existence of SOC saturation and a declined marginal efficiency of SOC sequestration. Taken all these results together, the combined NPK plus straw return is a suitable fertilizer management strategy to simultaneously achieve high crop productivity and soil C sequestration potential particularly in crop rotation systems. [ABSTRACT FROM AUTHOR]

In the present study, soil samples collected from 20-year (1993‒2013) long-term tobacco plantation and perennial fallow were analyzed to study the influence of soil acidification on soil physicochemical and mineralogical properties. Results showed a significant decrease of soil pH, Ca2+, Mg2+, Na+and total exchangeable cations, except K+, under tobacco plantation than under fallow land. Further X-ray diffraction (XRD) analysis for 1 mm soil size demonstrated an increase of vermiculite and kaolinite, but an obvious decrease of original potassium-bearing mica and potassium feldspar, under tobacco plantation than under fallow. For the <2 μm soil clay fraction, the XRD patterns showed an obvious desilication and accumulation of Al and Fe under tobacco plantation than under fallow. Other potassium-bearing minerals, such as illite and chlorite, had also visibly weathered and slaked under tobacco plantation than under fallow, resulting in an increase of vermiculite and hydroxy-Al-vermiculite, and an accelerated decomposition of 2:1 minerals and formation of 1:1 minerals. These results demonstrated that long-term continuous tobacco plantation has exerted negative effects on soil acidification and maintenance of soil potassium-bearing minerals. [ABSTRACT FROM AUTHOR]

Changes in soil exchangeable cations relative to soil acidification are less studied particularly under long-term cash crop plantation. This study investigated soil acidification in an Ali-Periudic Argosols after 10-year (2002-2012) long-term continuous tobacco plantation. Soils were respectively sampled at 1933 and 2143 sites in 2002 and 2012 (also 647 tobacco plants), from seven tobacco plantation counties in the Chongqing Municipal City, southwest China. After 10-year continuous tobacco plantation, a substantial acidification was evidenced by an average decrease of 0.20 soil pH unit with a substantial increase of soil sites toward the acidic status, especially those pH ranging from 4.5 to 5.5, whereas 1.93 kmol H production ha year was mostly derived from nitrogen (N) fertilizer input and plant N uptake output. After 1 decade, an average decrease of 27.6 % total exchangeable base cations or of 0.20 pH unit occurred in all seven tobacco plantation counties. Meanwhile, for one unit pH decrease, 40.3 and 28.3 mmol base cations kg soil were consumed in 2002 and 2012, respectively. Furthermore, the aboveground tobacco biomass harvest removed 339.23 kg base cations ha year from soil, which was 7.57 times higher than the anions removal, leading to a 12.52 kmol H production ha year as the main reason inducing soil acidification. Overall, our results showed that long-term tobacco plantation not only stimulated soil acidification but also decreased soil acid-buffering capacity, resulting in negative effects on sustainable soil uses. On the other hand, our results addressed the importance of a continuous monitoring of soil pH changes in tobacco plantation sites, which would enhance our understanding of soil fertility of health in this region. [ABSTRACT FROM AUTHOR]

In order to make the general user take vision tasks more flexibly and easily, this paper proposes a new solution for the problem of camera calibration from correspondences between model lines and their noisy image lines in multiple images. In the proposed method the common planar items in hand with the standard size and structure are utilized as the calibration objects. The proposed method consists of a closed-form solution based on homography optimization, followed by a nonlinear refinement based on the maximum likelihood approach. To automatically recover the camera parameters linearly, we present a robust homography optimization method based on the edge model by redesigning the classic 3D tracking approach. In the nonlinear refinement procedure, the uncertainty of the image line segment is encoded in the error model, taking the finite nature of the observations into account. By developing the new error model between the model line and image line segment, the problem of the camera calibration is expressed in the probabilistic formulation. Simulation data is used to compare this method with the widely used planar pattern based method. Actual image sequences are also utilized to demonstrate the effectiveness and flexibility of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, new solutions for the problem of pose estimation from correspondences between 3D model lines and 2D image lines are proposed. Traditional line-based pose estimation methods rely on the assumption that the noises (perpendicular to the line) for the two endpoints are statistically independent. However, these two noises are in fact negatively correlated when the image line segment is fitted using the least-squares technique. Therefore, we design a new error function expressed by the average integral of the distance between line segments. Three least-squares techniques that optimize both the rotation and translation simultaneously are proposed in which the new error function is exploited. In addition, Lie group formalism is utilized to describe the pose parameters, and then, the optimization problem can be solved by means of a simple iterative least squares method. To enhance the robustness to outliers existing in the match data, an M-estimation method is developed to convert the pose optimization problem into an iterative reweighted least squares problem. The proposed methods are validated through experiments using both synthetic and real-world data. The experimental results show that the proposed methods yield a clearly higher precision than the traditional methods. [ABSTRACT FROM AUTHOR]

When voyaging, ships are subject to inevitable hull deformations caused by the changes in the environmental temperature and external stress. These are a crucial source of errors when measuring data using a spacecraft tracking, telemetry, and control (TT&C) ship. A prototype system based on photogrammetry was developed for the real-time measurement of a spacecraft TT&C ship's hull deformation. This system has high accuracy, a simple structure, and convenient maintenance, and requires few changes to the ship's structures. To improve its performance, an estimation approach is proposed for hull deformation angles. With the proposed approach, the central positions of cross spots in successive frames can be predicted based on the prediction of the camera's attitude, and their extract locations can be found by defining a series of small windows around each predictive location. Then, the optimal estimate of the camera's attitude is updated by the designed extended Kalman filter using the extracted cross spots and their corresponding local coordinates, with which the hull deformation angles can be found. To verify the proposed measurement approach, its performance was tested during the normal sailing, floating, and rocking on the sea of a spacecraft TT&C ship. The experimental testing results demonstrated that the proposed approach performs well in terms of accuracy and robustness. It can satisfy the hull deformation measurement requirement for a spacecraft TT&C ship in real time. [ABSTRACT FROM AUTHOR]

The Ras-extracellular signal-regulated kinase (ERK) cascade is an important signaling module in cells. One regulator of the Ras-ERK cascade is phosphatidic acid (PA) generated by phospholipase D (PLD) and diacylglycerol kinase (DGK). Using a newly developed PA biosensor, PASS (phosphatidic acid biosensor with superior sensitivity), we found that PA was generated sequentially by PLD and DGK in epidermal growth factor (EGF)-stimulated HCC1806 breast cancer cells. Inhibition of PLD2, one of the two PLD members, was sufficient to eliminate most of the PA production, whereas inhibition of DGK decreased PA production only at the later stages of EGF stimulation, suggesting that PLD2 precedes DGK activation. The temporal production of PA by PLD2 is important for the nuclear activation of ERK. While inhibition of both PLD and DGK had no effect on the overall ERK activity, inhibition of PLD2 but not PLD1 or DGK blocked the nuclear ERK activity in several cancer cell lines. The decrease of active ERK in the nucleus inhibited the activation of Elk1, c-fos, and Fra1, the ERK nuclear targets, leading to decreased proliferation of HCC1806 cells. Together, these findings reveal that PA production by PLD2 determines the output of ERK in cancer cell growth factor signaling. [ABSTRACT FROM AUTHOR]

Imbalanced and excessive fertilizer application has resulted in low yields and reduced nutrient use efficiency for melon production in China. Estimating nutrient requirements is crucial for effectively developing site-specific fertilizer recommendations for increasing yield and profit while reducing negative environmental impacts. Relationships between the yield and nutrient uptake requirements of above-ground dry matter were assessed using 1127 on-farm observations (2000–2020) from melon production regions of China. The quantitative evaluation of fertility of tropical soils (QUEFTS) model was used to estimate nutrient requirements. It predicted a linear increase in yield at balanced nutrient uptake levels until the yield reached approximately 60–80% of the potential yield. In order to produce 1000 kg of fruit, 2.9, 0.4 and 3.2 kg/ha of N, P and K (7.2:1.0:7.8), respectively, were required for above-ground parts, while the corresponding nutrient internal efficiencies were 345.3, 2612.6 and 310.0 kg per kg N, P and K, respectively, whereas 1.4, 0.2 and 1.9 kg of N, P and K were required to replace nutrients removed after harvest. The corresponding fruit absorption rates were 47.0%, 59.5% and 58.2%, respectively. Field validation experiments confirmed the consistency between observed and simulated uptake rates, indicating that this model could estimate nutrient requirements. These findings will help develop fertilizer recommendations for improving melon yield and nutrient use efficiency. [ABSTRACT FROM AUTHOR]

With increasing water shortages in China, rice (Oryza sativa L.) cultivation is gradually shifting away from continuously flooded conditions to partly or even completely aerobic conditions. The effects of this shift on the growth and iron (Fe) nutrition of different aerobic and lowland rice genotypes are poorly understood. A field experiment was conducted to determine the effects of cultivation system (aerobic vs. flooded), genotype (five aerobic rice varieties and one lowland rice variety), and Fe fertilization [no Fe and 30 kg ha−1 ferrous sulfate (FeSO4·7H2O] on rice grain yield and Fe nutrition. Plants were sampled at tillering and physiological maturity. In both aerobic and flooded plots, Fe application significantly increased shoot dry weight, shoot Fe concentration, and shoot Fe content at tillering but not physiological maturity. At physiological maturity, grain yield and Fe and grain harvest indices were significantly lower in aerobic than in flooded plots. Shoot dry weight and shoot Fe content differed among genotypes at tillering and at physiological maturity. The grain harvest index of aerobic rice genotype 89B-271-17(hun) was significantly greater than that of the other five genotypes when no Fe was applied. Because soil Fe fertilization did not improve the Fe nutrition of rice in aerobic plots, the results indicate that the shift from flooded to aerobic cultivation will increase Fe deficiency in rice and will increase the problem of Fe deficiency in humans who depend on rice for nutrition. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common form of cancer among women. Compared with other serum polypeptides, autoantibodies have many appealing features as biomarkers including sensitivity, stability, and easy detection. Anti-lipid autoantibodies are routinely used in the diagnosis of autoimmune diseases, but their potential for cancer diagnosis has not been explored. Dysregulation of cellular signaling in cancer cells would be expected to lead to irregular metabolism of many lipids, which could be sensed by the immune system and cause the production of autoantibodies. Discovery of anti-lipid antibodies could be used as biomarkers for early breast cancer diagnosis. We describe here a more sensitive and accurate method for lipid microarray detection using dual fluorescent labeling, and used it to examine global anti-lipid profiles in the MMTV-Neu transgenic breast cancer model. We conclude that, at the current technology, lipid microarray is not a preferred method for anti-lipid antibody detection in breast cancer animal models. Our result will help the future application of lipid microarrays in identifying anti-lipid autoantibodies in breast cancer and other human diseases. [ABSTRACT FROM AUTHOR]

Fruit-wheat intercropping is an important way to resolve the land competition between fruit and grain and ensure food security. However, there is little research on the mechanism of wheat yield formation and its response to nitrogen fertilizer under long-term shading. From 2016 to 2017, wheat variety "Xindong 20" was selected, and four shading treatments were set: shading at jointing stage 10%-shading at heading stage 25% (S1), 20%–50% (S2), 30%–75% (S3), normal light (S0) and four nitrogen fertilizer (N0: 0 kg ha−1, N1: 103.5 kg ha−1, N2: 138 kg ha−1, N3: 172.5 kg ha−1). The results show that compared with S0, wheat leaf area index (LAI), chlorophyll a, b and a + b content under S1 increase by 14.9–57.4%, 2.9–24.5%, 16.5–28.9%, 7.8–25.5%, respectively, and they decrease significantly under S2 and S3. With the increase in the shading range, the net photosynthesis rate (Pn), transpiration rate (Tr), stomatal conductance (gs), and non-photochemical quentum coefficient (NPQ) decrease significantly, while the actual photochemical efficiency (ΦPSII) and the photochemical quenching coefficient (qP) increase significantly. Under S1, S2, and S3, the total dry matter accumulation (TDA), the dry matter accumulation of reproductive organs (DAR), and the yield decrease with the increase in shading range. Under the S0 and S1 conditions, compared with other nitrogen treatments, LAI, chlorophyll content, Pn, ΦPSII, qP, TDA, DAR, and yield of wheat under N2 treatment increase by 4.1–366.9%, 5.7–56.3%, 3.0–131.7%, 6.7–87.5%, 3.7–96.9%, 7.1–340.8%, 0.3–323.0%, 1.5–231.2%. Therefore, under jujube-wheat intercropping, and apricot-wheat and walnut-wheat with light shade in the early stage, photosynthetic capacity of wheat leaves and dry matter accumulation and transfer to grains can be regulated by proper nitrogen application, which is beneficial to compensate for the negative effects of insufficient light on wheat yield; under moderate or excessive shading conditions (apricot-wheat and walnut-wheat in full fruit period), the regulating effect of nitrogen application on wheat is reduced, and the nitrogen application should be moderately reduced. [ABSTRACT FROM AUTHOR]

Irrigation systems increase fruit yield of water shortage orchards in semiarid and arid lands, but their environmental impacts remain unclear. This study carries out a comparative cradle-to-gate life cycle assessment (LCA) of the furrow and drip irrigated pear production systems in the Loess Plateau of China based on 2009–2018 inventory data from integrated experimental stations. The water depletion (WD), water footprint (WF), global warming (GWP), acidification (AP), and eutrophication (EP) potentials of the furrow and drip irrigated pear production systems were calculated and compared, including the orchard installation phase (phase I), primary growing phase (phase II), low production phase (phase III), and full production phase (phase IV). Results indicated that the cumulative WD, GWP, AP, and EP of the drip irrigated system were 148.3 m3, 130.1 kg CO2-eq, 0.9 kg SO2-eq, and 0.6 kg PO4-eq per ton of pear fruit harvest, respectively, which were 37.3–73.5% lower than those of the furrow irrigated system. The GWP, AP, EP, and WD of phase I to III contributed 39.3–46.1% in the drip irrigated system vs. 27.8–38.6% in the furrow irrigated system of the total amount, which should not be neglected in perennial orchard systems. The annual WFs were 0.9, 0.2, and 0.2 m3 kg−1 year−1 in phases II, III, and IV of the drip system, respectively, which were 50–71.4% lower than that of the furrow system. Green WF of furrow and drip irrigated systems were approximately the same, but the blue WF and grey WF of drip irrigation systems were 35.7–62.1% and 66.0–73.2% lower than those of the furrow irrigated system. The drip irrigated pear production system significantly mitigated environmental impacts and WFs, mainly due to reduced fertilizer application, water consumption, electricity, and diesel demand. Irrigation that changed from a furrow to a drip system was responsible for most environmental reductions, but 8% decreases of yields in phase IV. The outcomes from assessing the furrow and drip irrigated pear production systems could provide useful information for decision-making by the pear orchardists in the Loess Plateau. [ABSTRACT FROM AUTHOR]

New shoots (including newly formed leaves and twigs) and fruits of citrus tree are key organs for present yield formation and flower differentiation in the next season, but the relationship between yield fluctuation and accumulations of major nutrients in new shoots and fruits of citrus tree is still unclear. Thus, to quantify the biomass and mineral nutrient accumulation in new shoots and fruits of citrus trees under varied yield levels has essential significance for rational fertilization and pruning management for citrus orchards. The purpose of this study was, therefore, to investigate the accumulation of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg), and the distribution of biomass in new shoots and fruits of citrus trees under low, medium and high-yield levels in each of eight orchards located in Chongqing, China. The results showed that substantial variation of fruit yield was observed in all eight orchards with an average yield of 15.0 (low), 30.9 (medium) and 60.1 (high) kg/plant. The averaged biomass of new shoots ranged from 1.59 to 2.51 kg/plant, which was significantly and positively correlated with fruit yield. Nutrient accumulation in leaves was generally highest among new organs, while more than half of N (52.70–71.4%), P (66.5–80.4%) and K (68.9–85.9%) accumulated in fruit. Fruit yields closely correlated with total amounts of major nutrients in new shoots. Furthermore, the nutrient requirements per unit of newly developed shoots and fruits were gradually decreased with increased yield, but the removed nutrients per ton of fresh fruit were almost stable, indicating that more nutrients were distributed into fruit tissues. Taken together, these findings are valuable for optimizing nutrient and pruning management in citrus orchards in China and other similar countries. [ABSTRACT FROM AUTHOR]

Estimating balanced nutrient requirements for a watermelon plantation is essential to increase its fruit yield and nutrient use efficiency. This is vital for China, which produces 60% of world's watermelons with excessive fertilizer application. Therefore, datasets between 2000 and 2019 from field experiments in major watermelon producing regions across China were collected to assess relationships between fruit yield and nutrient uptake, and to estimate nitrogen (N), phosphorus (P), and potassium (K) requirements for a target yield using a modified Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model. The results showed that the QUEFTS model predicted a linear increase in fruit yield to 60–70% of the total potential yield when balanced amounts of N, P, and K nutrients were absorbed. To produce 1000 kg of watermelon, 2.11 kg N, 0.27 kg P, and 2.69 kg K were required in shoot, and the corresponding internal efficiencies (IE) were 475, 3682, and 372 kg fruit per kg of N, P, and K, respectively. The modified QUEFTS model also simulated a balanced N, P, and K removal by fruit (accounting for 50.9%, 58.2%, and 66.4% of these nutrient accumulations in shoots, respectively). Field validation experiments further verified that the modified QUEFTS model could be used for estimating balanced nutrient requirements. Results from this study can provide practical guidance on fertilizer recommendations for improving fruit yield while preventing excessive or deficient nutrient supplies in China's watermelon plantations. [ABSTRACT FROM AUTHOR]

Scanning Kelvin probe microscopy (SKPM), electrostatic force microscopy (EFM) are used to study the microscopic processes of the photo-induced charge separation at the interface of Ag and conductive polymers, i.e., poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-bʹ]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and poly(3-hexylthiophene-2,5-diyl) (P3HT). They are also widely used in order to directly observe the charge distribution and dynamic changes at the interfaces in nanostructures, owing to their high sensitivity. Using SKPM, it is proved that the charge of the photo-induced polymer PCPDTBT is transferred to Ag nanoparticles (NPs). The surface charge of the Ag-induced NPs is quantified while using EFM, and it is determined that the charge is injected into the polymer P3HT from the Ag NPs. We expect that this technology will provide guidance to facilitate the separation and transfer of the interfacial charges in the composite material systems and it will be applicable to various photovoltaic material systems. [ABSTRACT FROM AUTHOR]

The environmental sustainability of the largest citrus plantation globally is facing a great challenge in China. Further, there is a lack of quantitative, regional hotspot studies. In this study, the life cycle assessment (LCA) was used to quantify the environmental cost of citrus production based on 155 farmers' surveys from typical citrus orchards in Danling County, southwest China, which produced 0.65% of the country's total citrus production. The results showed that the average values of environmental risk indicated by global warming potential (GWP), acidification potential (AP), and eutrophication potential (EP) were 11,665 kg CO2-eq ha−1, 184 kg SO2-eq ha−1, and 110 kg PO4-eq ha−1, respectively. The production and utilization of fertilizer ranked the first contribution to the environmental impacts among all the environmental impacts, which contributed 92.4–95.1%, 89.4–89.8%, and 97.8–97.9% to global warming potential, acidification potential, and eutrophication potential, respectively. Specific to the contribution of fertilizers to environmental costs, the production and utilization of nitrogen (N) fertilizer accounted for more than 95% of the total environmental costs. Thus, the spatial distribution of environmental costs in this county was well matched with that of N input. Compared with the average values of investigated 155 orchards, the high yield and high N use efficiency (HH) orchard group with younger and better educated owners achieved a higher citrus yield and N use efficiency with less fertilizer input and lower environmental costs. Five field experiments conducted by local government and Danling Science and Technology Backyard were used to further certify the reduction potential of environment costs. These field results showed that the local recommendation (LR) treatment increased citrus yield and N use efficiency by 1.9–49.5% and 38.0–116%, respectively, whereas decreased environmental costs by 21.2–35.2% when compared with the local farmer practice in the HH orchard group. These results demonstrated that an optimum nutrient management based on the local field recommendation in citrus-producing areas is crucial for achieving a win-win target of productivity and environmental sustainability in China and other, similar countries. [ABSTRACT FROM AUTHOR]

With increasing application of nitrogen (N), phosphorus (P), and potassium (K) fertilizers, especially in China's fruit crops, the agronomic responses of fruit crops to fertilization may be reduced with time. Thus, the quantification of these responses would be useful for establishing nutrient recommendation and fertilizer management for fruit crops. Here, a meta-analysis including 552 paired data for agronomic response and 1283 sets for amounts of optimal fertilization from 293 field studies in China were performed to systemically quantify these variations of yield response (YR), relative yield (RY), agronomic efficiency (AE), and partial factor productivity (PFP) in response to the application of N, P, or K fertilizer under different groups including fruit crop types, time, and regions. The results showed that the average YRs to N, P or K fertilizer were 7.6, 5.2, or 5.9 t ha−1, indicating related RYs of 78.0%, 82.9%, or 82.4%, respectively. All of the RYs for N, P, or K application in studies after 2000 were higher and less variable than those before 2000. Higher RYs were also shown for deciduous fruit trees when compared with evergreen fruit trees. The average AEs of N, P, and K fertilizer in China's fruit crops were 29.1, 32.4 and 20.2 kg kg−1, all of them were negatively correlated with fertilizer rate. Due to a higher yield response and less fertilizer rate, annual crops (mainly watermelon and melons) had significantly higher AE than that of perennial crops. The average PFPs of N, P, and K fertilizer in China's fruit crops were 129, 205, and 113 kg kg−1, all of which showed a declining trend with time. These findings demonstrated that the building-up of soil indigenous nutrient supply (indicated by RY) together with improving fruit varieties, as well as pest management and other forms of management could make external fertilization less important for increasing the yield of fruit crops in China. A rational nutrient management is therefore crucial for balancing yield and environmental concerns in countries like China, India, and other countries where fertilizers are often overused. [ABSTRACT FROM AUTHOR]