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Steel truss bridges are especially vulnerable in the event of a sudden loss of a load-carrying element, which can trigger a chain of failures. This paper describes a unique case study of a steel truss bridge under construction subjected to sudden member breakages with an extensive monitoring system. The failures occurred during the dismantlement of temporary members that had been used to transform a three-span simply supported steel truss bridge into a three-span continuous structure during incremental launching. These temporary members needed to be removed once the bridge reached its final position. The robustness of the bridge was assessed using computer simulations of various failure scenarios to evaluate its capacity to effectively activate alternative load paths (ALPs). The results demonstrated the structural redundancy of the steel truss bridge. However, the dynamic response resulting from the failure of the temporary upper chord, due to the initially high tension in the rods, should not be overlooked. To mitigate this issue, a structural retrofitting method was proposed, involving jacking the truss girder above the side pier to reduce the tension in the temporary upper chord above the middle pier. The effectiveness of this method was demonstrated through both simulated and formal experimental tests. [ABSTRACT FROM AUTHOR]

Thioredoxin (TRX) is a small protein with REDOX activity that plays a crucial role in a plant's growth, development, and stress resistance. The TRX family has been extensively studied in Arabidopsis, rice, and wheat, and so it is likely that its members have similar biological functions in Liriodendron that have not been reported in Liriodendron. In this study, we performed the genome-wide identification of the TRX gene family based on the Liriodendron chinense genome, leading to a total of 42 LcTRX gene members. A phylogenetic analysis categorized these 42 LcTRX proteins into 13 subfamilies. We further characterized their chromosome distributions, gene structures, conserved protein motifs, and cis-elements in the promoter regions. In addition, based on the publicly available transcriptome data for Liriodendron hybrid and following RT-qPCR experiments, we explored the expression patterns of LhTRXs to different abiotic stressors, i.e., drought, cold, and heat stress. Notably, we found that several LhTRXs, especially LhTRX-h3, were significantly upregulated in response to abiotic stress. In addition, the subcellular localization assay showed that LhTRX-h3 was mainly distributed in the cytoplasm. Subsequently, we obtained LhTRX-h3 overexpression (OE) and knockout (KO) callus lines in Liriodendron hybrid. Compared to the wild type (WT) and LhTRX-h3-KO callus proliferation of LhTRX-h3-OE lines was significantly enhanced with reduced reactive oxygen species (ROS) accumulation under drought stress. Our findings that LhTRX-h3 is sufficient to improve drought tolerance. and underscore the significance of the TRX gene family in environmental stress responses in Liriodendron. [ABSTRACT FROM AUTHOR]

Soil moisture (SM) is a crucial environmental variable, and it plays an important role in energy and water cycles. SM data retrieval based on microwave satellite remote sensing has garnered significant attention due to its spatial continuity, wide observational coverage, and relatively low cost. Validating the accuracy of satellite remote sensing SM products is a critical step in enhancing data credibility, which plays a vital role in ensuring the effective application of satellite remote sensing data across various fields. Firstly, this study focused on Henan Province and evaluated the accuracy of the SMAP Enhanced L3 Radiometer Global and Polar Grid Daily 9 km EASE-Grid Soil Moisture (SPL3SMP_E) product along with its application in agriculture. The evaluation was based on in situ SM data from 55 stations in Henan Province. The assessment metrics used in this study include mean difference (MD), root mean square error (RMSE), unbiased root mean square error (ubRMSE), and the Pearson correlation coefficient (R). The time span of this study is from 2017 to 2020. The evaluation results indicated that the SPL3SMP_E soil moisture product performs well, as reflected by an ubRMSE value of 0.045 (m3/m3), which was relatively close to the product's design accuracy of 0.04 (m3/m3). Moreover, the accuracy of the product was unaffected by temporal factors, but the product exhibited strong spatial aggregation, which was closely related to land use types. Then, this study explored the response of the SPL3SMP_E product to irrigation signals. The precipitation and irrigation data from Henan Province were employed to investigate the response of the SPL3SMP_E soil moisture product to irrigation. Our findings revealed that the SPL3SMP_E soil moisture product was capable of capturing over 70% of irrigation events in the study area, indicating its high sensitivity to irrigation signals in this region. In this study, the SPL3SMP_E product was also employed for monitoring agricultural drought in Henan Province. The findings revealed that the collaborative use of the SPL3SMP_E soil moisture product and machine learning algorithms proves highly effective in monitoring significant drought events. Furthermore, the integration of multiple indices demonstrated a notable enhancement in the accuracy of drought monitoring. Such an evaluation holds significant implications for the effective application of satellite remote sensing SM data in agriculture and other domains. [ABSTRACT FROM AUTHOR]

Characterized by soil moisture content and plant growth, agricultural drought occurs when the soil moisture content is lower than the water requirement of plants. Microwave remote sensing observation has the advantages of all-weather application and sensitivity to soil moisture change. However, microwave remote sensing can only invert 0~5 cm of soil surface moisture, so it cannot effectively reflect the drought situation of farmland. Therefore, this study took Henan Province as the study area, used soil moisture active and passive (SMAP) satellite soil moisture data, employed NDVI, LST, and ET as the independent variables, and took the drought grade on the sample as the dependent variable. Using the 2017–2019 data as the training set and the 2020 data as the testing set, a random forest drought monitoring model with comprehensive influence of multiple factors was constructed based on the training set data. In the process of model training, the cross-validation method was employed to establish and verify the model. This involved allocating 80% of the sample data for model construction and reserving 20% for model verification. The results demonstrated an 85% accuracy on the training set and an 87% accuracy on the testing set. Additionally, two drought events occurring during the winter wheat growing period in Henan Province were monitored, and the validity of these droughts was confirmed using on-site soil moisture and the vegetation supply water index (VSWI). The findings indicated a high incidence of agricultural drought in the southwestern part of Henan Province, while the central and northern regions experienced a lower incidence during the jointing to heading and filling stages. Subsequently, leveraging the results from the random forest drought monitoring, this study conducted a time series analysis using the Mann–Kendall test and a spatial analysis employing Moran's I index to examine the temporal and spatial distribution of agricultural drought in Henan Province. This analysis aimed to unveil trends in soil moisture changes affecting agricultural drought, as observed via the SMAP satellite (NASA). The results suggested a possible significant spatial auto-correlation in the occurrence of agricultural drought. [ABSTRACT FROM AUTHOR]

Heat shock factors (Hsfs) play a crucial role in plant defense processes. However, the distribution and functional characteristics of Hsf genes in the relict plant Liriodendron chinense are still unclear. In this study, a total of 19 LcHsfs were identified and divided into three separate subgroups, comprising 10 LcHsfA, 7 LcHsfB, and 2 LcHsfC genes, respectively, based on their phylogenetic tree and the presence/absence of conserved protein domains. Whole-genome duplication and segmental duplication led to an expansion of the LhHsf gene family. The promoters of LcHsf genes are enriched for different types of cis-acting elements, including hormone responsive and abiotic-stress-responsive elements. The expression of LcHsfA3, LcHsfA4b, LcHsfA5, LcHsfB1b, and LcHsfB2b increased significantly as a result of both cold and drought treatments. LcHsfA2a, LcHsfA2b, and LcHsfA7 act as important genes whose expression levels correlate strongly with the expression of the LcHsp70, LcHsp110, and LcAPX genes under heat stress. In addition, we found that transiently transformed 35S:LcHsfA2a seedlings showed significantly lower levels of hydrogen peroxide (H2O2) after heat stress and showed a stronger thermotolerance. This study sheds light on the possible functions of LcHsf genes under abiotic stress and identifies potentially useful genes to target for molecular breeding, in order to develop more stress-resistant varieties. [ABSTRACT FROM AUTHOR]

In order to investigate the equivalent complex refractive index of atmospheric aerosols near the Earth's surface, we conducted measurements in the Hefei region from March to April 2022. These measurements utilized a micro-pulse lidar, an Aethalometer, and a Portable Optical Particle Profiler. These measurements encompassed aerosol particle size distribution as well as standard meteorological parameters including temperature, humidity, atmospheric pressure, and wind speed. Subsequently, this dataset was employed to develop an optimization algorithm for retrieving the equivalent complex refractive indices of near-surface aerosols. The methodology relies on lookup tables containing data for extinction efficiency and absorption efficiency factors. It operates on the premise of aerosol property stability within a defined time frame, utilizing measured extinction and absorption coefficients as simultaneous constraints during this period to inversely derive both the real and imaginary parts of the aerosol complex refractive index. Results from the simulation analysis reveal that the newly optimized retrieval algorithm, which relies on lookup tables, exhibits reduced sensitivity to instrument errors when compared to single-point constraint algorithms. This enhancement results in a more efficient and dependable approach for retrieving the aerosol complex refractive index. Empirical inversion and simulation studies were carried out to determine the aerosol equivalent complex refractive index in the Hefei region, utilizing measured data. This inversion process yielded an average complex refractive index of 1.48-i0.017 for aerosols in the Hefei region throughout the experimental period. Correlation analysis unveiled a positive association between the real part of the aerosol complex refractive index and the single-scattering albedo (SSA), whereas the imaginary part displayed a linear negative correlation with the SSA. The mathematical relationship between the real part and the SSA is y = 0.19 x + 0.62 , and the corresponding relationship between the imaginary part and the SSA is y = − 5.3 x + 0.99 . This research offers a novel method for the retrieval of the aerosol equivalent complex refractive index. [ABSTRACT FROM AUTHOR]

Background: Studying the effects of traffic vibration on adjacent structures has produced fruitful results, but there is a lack of systematic research on the protection, assessment, and ambient vibration effects on cultural relics, and the majority of the studies focus on above-ground buildings, with less research conducted on underground cultural relic sites. Objective: In order to investigate the effects of road-traffic-induced vibration on nearby underground sites, the distance between them was precisely determined. Methodology/approach: The site of Chengshang Village in Jurong City, Nanjing, China, was chosen as the research object, and the vibration of the underground site caused by traffic volume was measured on-site. Based on statistical analysis of experimental data, the vibration velocity was deduced as a function of the vehicle's speed and the vibration source's distance. Results: The excellent frequency band for traffic load vibration is between 0 and 40 Hz, and the attenuation speed of high-frequency vibration is faster than that of low-frequency vibration; the vibration speed is positively correlated with the speed of the vehicle, and the distance from the vibration source is exponentially attenuated; and under the condition of the determined limit value of the load and the vibration speed, the safety distance increases. Conclusions: This research utilizes the collected data to describe the relationship between the vibration velocity and the distance from the vibration source. Additionally, it estimates the appropriate distance at which cultural relics should be placed from the road to ensure their safety. The study's findings may serve as a valuable point of reference for traffic planning and the preservation of underground cultural monuments. [ABSTRACT FROM AUTHOR]

Background: Tied-arch bridges' hangers are crucial load-bearing parts, and their excellent condition directly influences bridge safety. However, assessing in-service hangers' continuing functional performance is irrelevant and incomplete, particularly for unique hangers covered by outer steel tubes. Objective: This research uses a case study of an under-bearing tied-arch bridge with substantial hanger damage to determine the origin of the damage and analyze the hanger's remaining operational ability. Methodology/approach: This study presents a set of assessment methodologies and procedures for in-service hangers' remaining functioning performance using field inspection and indoor tests. First, an appearance inspection of the full bridge hanger's upper and lower anchor heads was carried out, and the categories of anchor head damage and distribution rules are summarized. The causes of major water damage and the lower anchor head's water infiltration channel were explored. Then, a full interior test was performed on the disassembled sick hanger to establish its present mechanical qualities. Finally, field inspection and indoor test findings assessed the bridge hanger's operational performance. The findings suggest that the anchor box drainage prevention system should be improved to prevent rainfall and condensation from pooling in the lower anchor box and causing anticorrosive grease failure and anchor head corrosion. Results: The hanger's mechanical qualities have deteriorated and no longer meet usage standards. Most of the water accumulated in the anchor head of the conventional construction hanger enters from the bridge deck or rope surface, but because of the outer steel pipe, rainwater can flow into the lower anchor box through the upper anchor box along the gap between the hanger and the outer steel pipe, so the waterproof system of the upper anchor box should be checked. Conclusions: This research may be used for safety evaluation and maintenance of the same hanger in service. [ABSTRACT FROM AUTHOR]

Accurate irrigation water-use data are essential to agricultural water resources management and optimal allocation. The obscuration presented by ground cover in farmland and the subjectivity of irrigation-related decision-making processes mean that effectively identifying regional irrigation water use remains a critical problem to be solved. In view of the advantages of satellite microwave remote sensing in monitoring soil moisture, previous studies have proposed a method for estimating irrigation water use using the satellite microwave remote sensing of soil moisture. However, the method is affected by false irrigation signals from soil moisture increases caused by non-irrigation factors, causing irrigation water use to be overestimated. Therefore, the purpose of this study is to improve the estimation of irrigation water use in drylands by using irrigation signals from SMAP soil moisture data. In this paper, the irrigation water use in Henan Province is estimated by using the irrigation signals from SMAP (soil moisture active and passive) soil moisture data. Firstly, a method for recognizing irrigation signals in soil moisture data obtained by microwave satellite remote sensing was used. Then, an estimation model of the amount of irrigation water (SM2Rainfall model) was built on each data pixel of the satellite microwave remote sensing of soil moisture. Finally, the amount of irrigation water utilized in Henan Province was estimated by combining the irrigation signals and irrigation water-use estimation model, and the results were evaluated. According to the findings, this study improved the estimation accuracy of irrigation water use by using the irrigation signals in Henan Province. The result of this study is of great importance to accurately obtain irrigation water use in the region. [ABSTRACT FROM AUTHOR]

This study addresses the problem of restricted ability for large-scale monitoring due to the limited cruising time of unmanned aerial vehicles (UAV) by identifying an optimal leaf ChlorophyII content (LCC) inversion machine learning model at different scales and under different parameterization schemes based on simultaneous observations of ground sampling, UAV flight, and satellite imagery. The following results emerged: (1) The correlation coefficient between most remote sensing features (RSFs) and LCC increased as the remote scale expanded; thus, the scale error caused by the random position difference between GPS and measuring equipment should be considered in field sampling observations. (2) The LCC simulation accuracy of the UAV multi-spectral camera using four machine learning algorithms was ExtraTree > GradientBoost > AdaBoost > RandomForest, and the 20- and 30-pixel scales had better accuracy than the 10-pixel scale, while the accuracy for three feature combination schemes ranked combination of extremely significantly correlated RSFs > combination of significantly correlated and above RSFs > combination of all features. ExtraTree was confirmed as the optimal model with the feature combination of scheme 2 at the 20-pixel scale. (3) Of the Sentinel-2 RSFs, 27 of 28 were extremely significantly correlated with LCC, while original band reflectance was negatively correlated, and VIs were positively correlated. (4) The LCC simulation accuracy of the four machine learning algorithms ranked as ExtraTree > GradientBoost > RandomForest > AdaBoost. In a comparison of two parameterization schemes, scheme 1 had better accuracy, while ExtraTree was the best algorithm, with 11 band reflectance as input RSFs; the RMSE values for the training and testing data sets of 0.7213 and 1.7198, respectively. [ABSTRACT FROM AUTHOR]

Cement-based materials, especially those with low water-cement ratios, often experience premature cracking due to plastic shrinkage in the early curing stages. In this study, the development mechanism of early-age plastic shrinkage of cement paste, and the crack shrinkage control effect of recycled cement paste powder on cement paste, was quantitatively investigated using non-contacting two-dimensional digital image technology. The influence of different replacement rates (5%, 10%, 20% and 30%) of recycled cement paste powder on the major principal strain and crack patterns of cement paste was investigated. Furthermore, the mechanism of recycled cement paste powder on the early-age plastic shrinkage of cement-based materials was explored. The results show that the addition of recycled cement paste powder could suppress the early-age plastic shrinkage of cement paste. An appropriate replacement ratio (10%) of recycled cement paste powder shows a 33.3% time delay in crack appearance and a 28.0% reduction in the major principal strain. However, the higher replacement ratio of 30% shows an adverse effect on the major principal strain, with an increase of 35.1%. The core mechanism of the appropriate recycled cement paste powder on plastic shrinkage reduction lies in its porous nature, which allows for water absorption and release and regulates the moisture state inside the pores. This quantitative research of the major principal strain development of the early-age plastic shrinkage of cement paste can facilitate a better understanding of plastic shrinkage reduction in recycled cement paste powder on cement paste. [ABSTRACT FROM AUTHOR]

Liriodendron chinense is a tree species of the Magnoliaceae family, an ancient relict plant mainly used for landscaping and timber production due to its excellent material properties and ornamental value. The cytokinin oxidase/dehydrogenase (CKX) enzyme regulates cytokinin levels and plays an important role in plant growth, development, and resistance. However, too-high or too-low temperatures or soil drought can limit the growth of L. chinense, representing a key issue for research. Here, we identified the CKX gene family in the L. chinense genome and examined its transcriptional responses to cold, drought, and heat stresses. A total of five LcCKX genes, distributed on four chromosomes and divided into three phylogenetic groups, were identified across the whole L. chinense genome. Further analysis showed that multiple hormone- and stress-responsive cis-acting elements are located in the promoter regions of LcCKXs, indicating a potential role of these LcCKXs in plant growth, development, and response to environmental stresses. Based on existing transcriptome data, LcCKXs, especially LcCKX5, were found to transcriptionally respond to cold, heat, and drought stresses. Furthermore, quantitative reverse-transcription PCR (qRT-PCR) showed that LcCKX5 responds to drought stress in an ABA-dependent manner in stems and leaves and in an ABA-independent manner in roots. These results lay a foundation for functional research on LcCKX genes in the resistance breeding of the rare and endangered tree species of L. chinense. [ABSTRACT FROM AUTHOR]

Carotenoid cleavage oxygenase (CCO) is an enzyme that can catalyze carotenoids to volatile aromatic substances and participate in the biosynthesis of two important phytohormones, i.e., abscisic acid (ABA) and strigolactone (SL). However, the genome-wide identification and analysis of the CCO gene family in the rare and endangered woody plant Liriodendron chinense has not been reported. Here, we performed a genome-wide analysis of the CCO gene family in the L. chinense genome and examined its expression pattern during different developmental processes and in response to various abiotic stresses. A total of 10 LcCCO genes were identified and divided into 6 subfamilies according to the phylogenetic analysis. Subcellular localization prediction showed that most of the LcCCO proteins were located in the cytoplasm. Gene replication analysis showed that segmental and tandem duplication contributed to the expansion of this gene family in the L. chinense genome. Cis-element prediction showed that cis-elements related to plant hormones, stress and light response were widely distributed in the promoter regions of LcCCO genes. Gene expression profile analysis showed that LcNCED3b was extensively involved in somatic embryogenesis, especially the somatic embryo maturation, as well as in response to heat and cold stress in leaves. Furthermore, qRT-PCR analysis showed that LcNCED3b obviously responded to drought stress in roots and leaves. This study provides a comprehensive overview of the LcCCO gene family and a potential gene target for the optimization of the somatic embryogenesis system and resistance breeding in the valuable forest tree L. chinense. [ABSTRACT FROM AUTHOR]

Water quality is directly linked to drinking water safety for millions of people receiving the water. The Danjiangkou Reservoir is the main water source for the Middle Route of the South-to-North Water Diversion Project (MR-SNWDP), located in the vicinity of Henan and Hubei provinces in China. Aquatic microorganisms are key indicators of biologically assessing and monitoring the water quality of the reservoir as they are sensitive to environmental and water quality changes. This study aimed to investigate the spatiotemporal variations in bacterioplankton communities during wet (April) and dry (October) seasons at eight monitoring points in Hanku reservoir and five monitoring points in Danku reservoir. Each time point had three replicates, labeled as wet season Hanku (WH), wet season Danku (WD), dry season Hanku (DH), and dry season Danku (DD) of Danjiangkou Reservoir in 2021. High-throughput sequencing (Illumina PE250) of the 16S rRNA gene was performed, and alpha (ACE and Shannon) and beta (PCoA and NDMS) diversity indices were analyzed. The results showed that the dry season (DH and DD) had more diverse bacterioplankton communities compared to the wet season (WH and WD). Proteobacteria, Actinobacteria, and Firmicutes were the most abundant phyla, and Acinetobacter, Exiguobacterium, and Planomicrobium were abundant in the wet season, while polynucleobacter was abundant in the dry season. The functional prediction of metabolic pathways revealed six major functions including carbohydrate metabolism, membrane transport, amino acid metabolism, signal transduction, and energy metabolism. Redundancy analysis showed that environmental parameters greatly affected bacterioplankton diversity during the dry season compared to the wet season. The findings suggest that seasonality has a significant impact on bacterioplankton communities, and the dry season has more diverse communities influenced by environmental parameters. Further, the relatively high abundance of certain bacteria such as Acinetobacter deteriorated the water quality during the wet season compared to the dry season. Our findings have significant implications for water resource management in China, and other countries facing similar challenges. However, further investigations are required to elucidate the role of environmental parameters in influencing bacterioplankton diversity in order to devise potential strategies for improving water quality management in the reservoir. [ABSTRACT FROM AUTHOR]

Cunninghamia lanceolata (Lamb.) Hook. (Chinese fir) is an important timber species that is widely cultivated in southern China. However, the shallow root system and weak drought resistance of Chinese fir are not enough to cope with high temperature and drought. In recent years, molecular biology has been used to modify plants to make them more resilient. Therefore, improving heat and drought resistance of Chinese fir by molecular biology technology is one of the best choices, whereas fewer genetic information resources for C. lanceolata limit more comprehensive molecular studies. In this study, single-molecule full-length transcriptome (SMRT) sequencing technology was used to obtain full-length transcriptome data on Chinese fir. A total of 21,331 transcripts were obtained via co-assembly, and 11,094 gene sets were obtained via further de-redundancy. In addition, gene function annotation and gene structure analysis were performed. We also used these data to identify nine heat shock transcription factors (Hsfs) in Chinese fir, and heat stress transcriptome and real-time quantitative polymerase chain reaction (PCR) analyses revealed expression changes in response to heat stress, indicating that these may play roles in heat resistance. These studies have enriched the genetic information resources of Chinese fir, which may be utilized for further species promotion, improvement, and application. [ABSTRACT FROM AUTHOR]

Plant glutathione peroxidases (GPXs) are the main enzymes in the antioxidant defense system that sustain H2O2 homeostasis and normalize plant reaction to abiotic stress conditions. However, the genome-wide identification of the GPX gene family and its responses to environmental stresses, especially salt stress, in Nitraria sibirica, which is a shrub that can survive in saline environments, has not yet been reported. Here, we first report the genome-wide analysis of the GPX gene family in N. sibirica, leading to a total of seven NsGPX genes that are distributed on six of the twelve chromosomes. Phylogenetic analysis showed that NsGPX genes were grouped into four major groups (Group I-IV). Three types of cis-acting elements were identified in the NsGPX promoters, mainly related to hormones and stress response. The quantitative real-time PCR (qRT-PCR) analysis indicated that NsGPX1 and NsGPX3 were significantly up-regulated in stem and leaf, while NsGPX7 transcriptionally in root in response to salt stress. The current study identified a total seven NsGPX genes in N. sibirica via genome-wide analysis, and discovered that NsGPXs may play an important role in response to salt stress. Taken together, our findings provide a basis for further functional studies of NsGPX genes, especially in regarding to the resistance to salt stress of this halophyte plant N. sibirica, eventually aid in the discovery of new methods to restore overtly saline soil. [ABSTRACT FROM AUTHOR]

The ability to obtain an accurate measure of irrigation water use is urgently needed in order to provide further scientific guidance for irrigation practices. This investigation took soil moisture and precipitation as the study objects and quantitatively analyzed their relationship by establishing four models: a linear model, a logarithmic model, a soil water balance model, and a similarity model. The results from building models on every site clearly revealed the relationship between soil moisture and precipitation and confirmed the feasibility of estimating irrigation water use when soil moisture data are known. Four models combined with soil moisture data were used to estimate irrigation water use. First, the 16 sites which monitor soil moisture conditions in Hebi City were identified as study objects, from which everyday meteorological data (temperature, precipitation, atmospheric pressure, wind speed, sunshine duration) and soil moisture data from 2015 to 2020 (totaling six years) were collected. Second, the eligible data from the first four years in the date range were used to create four kinds of models (linear model, logarithmic model, soil water balance model, and similarity model) to estimate the amount of water input to the soil surface based on soil moisture. Third, the eligible data from the last two years in the established date range were used to verify the established models on every site and then judge the accuracy of the models. For example, for site 53990, the RMSE of the linear model, logarithmic model, soil water balance model, and similarity model was 10,547, 10,302, 8619, and 7524, respectively. The results demonstrate that the similarity model proposed in this study can express the quantitative relationship between soil moisture and precipitation more accurately than the other three models. Based on this conclusion, the eligible soil moisture data known in the specific site were ultimately used to estimate the irrigation water use in the field by the relationship expressed in the similarity model. Compared with the amount of irrigation water data recorded, the estimated irrigation water use yielded by the similarity model in this study was 18.11% smaller. In a future study, microwave satellite remote sensing of soil moisture data, such as SMAP and SMOS soil moisture data, will be used to evaluate the performance of estimated regional irrigation water use. [ABSTRACT FROM AUTHOR]

In this study, we devised a constraint method, called multi-model ensemble pattern (MEP), to estimate the refractive index structure parameter ( C n 2 ) profiles based on observational data and multiple existing models. We verified this approach against radiosonde data from field campaigns in China's eastern and northern coastal areas. Multi-dimensional statistical evaluations for the C n 2 profiles and integrated astronomical parameters have proved MEP's relatively reliable performance in estimating optical turbulence in the atmosphere. The correlation coefficients of MEP and measurement overall C n 2 in two areas are up to 0.65 and 0.76. A much higher correlation can be found for a single radiosonde profile. Meanwhile, the difference evaluation of integrated astronomical parameters also shows its relatively robust performance compared to a single model. The prowess of this reliable approach allows us to carry out regional investigation on optical turbulence features with routine meteorological data soon. [ABSTRACT FROM AUTHOR]

Superoxide dismutase (oxide dismutase) is an enzyme synthesized via the expression of SOD-related genes. It is the first line of defense against oxygen free radicals, and it widely exists in the cytoplasm, chloroplasts, and mitochondria. However, the SOD gene family of woody plant Liriodendron chinense has not been studied. To reveal the potential role of SOD genes, we systematically identified and analyzed the SOD gene family of L. chinense, and investigated the transcriptional responses of LcSOD genes to several abiotic stresses, including cold, heat, and drought. A total of eight SOD genes were identified, namely, five Cu/Zn-SODs, two Fe-SODs, and one Mn-SOD, and they were divided into two subgroups according to phylogenetic analysis, gene structure, and conserved motifs. Cis-acting element analysis reveals various hormones and stress respond as cis-acting elements in the promoters of LcSODs. Gene expression analysis shows that most LcSOD genes were in response to abiotic stresses at the transcriptional level. These results help in clarifying the function of LcSOD genes under abiotic stresses, and provide potential targets for the improvement in abiotic stress tolerance in the endangered L. chinense. [ABSTRACT FROM AUTHOR]

The development and application of new Fiber Reinforced Polymer (FRP) material and 3D printing construction technology provide a basis for making up for the shortcomings of traditional thin-shell structures and building new thin-shell structures with better performance. In this paper, a new 3D Printing Composite (3DPC) thin-shell structure is proposed, which is prepared using a FRP plate as a permanent base mold and combining it with 3D printing cement technology. Both the typical experiment and finite element numerical simulation analysis of the 3DPC thin-shell structure are carried out. The results show that the maximum load capacity of the 3DPC thin-shell structure is increased by 53.3% as compared with the corresponding traditional concrete thin-shell structure. The presence of the FRP sheet effectively delays the generation of initial cracks and enhances the ductility of components. [ABSTRACT FROM AUTHOR]

Cantilever brackets have been widely used in buildings to provide support for all kinds of pipes. In order to improve the bearing capacity of cantilever brackets, two types of reinforcement schemes are proposed, one is to sleeve a pipe, and the other is to add a haunch. Their mechanical properties are studied by numerical simulation and experimental investigation. First, the non-linear finite element (FE) simulation analysis was carried out, and the structural bearing capacity, stress distribution, and failure modes were discussed. Then, the full-scale model tests were completed to provide validation of the FE analysis. On this basis, a comparison of the FE results and test results of three kinds of cantilever brackets was discussed in detail. The results show that two reinforcement schemes can enhance the bearing capacity of the cantilever bracket significantly by 38.3% and 25.9%, respectively, and they are applicable for the reinforcement of existing cantilever brackets. [ABSTRACT FROM AUTHOR]

The calcineurin B-like-interacting protein kinase (CIPK) protein family plays a key role in the plant calcium ion-mediated signal transduction pathway, which regulates a plant's response to abiotic stress. Nitraria sibirica pall. (N. sibirica) is a halophyte with a strong tolerance for high salt environments, yet how it is able to deal with salt stress on a molecular level is still unknown. Due to their function as described in other plant species, CIPK genes are prime candidates for a role in salt stress signaling in N. sibirica. In this study, we identified and analyzed the phylogenetic makeup and gene expression of the N. sibirica CIPK gene family. A total of 14 CIPKs were identified from the N. sibirica genome and were clustered into seven groups based on their phylogeny. The promoters of NsCIPK genes contained multiple elements involved in hormonal and stress response. Synteny analysis identified a total of three pairs of synteny relationships between NsCIPK genes. Each gene showed its own specific expression pattern across different tissues, with the overall expression of CIPK6 being the lowest, and that of CIPK20 being the highest. Almost all CIPK genes tended to respond to salt, drought, and cold stress, but with different sensitivity levels. In this study, we have provided a general description of the NsCIPK gene family and its expression, which will be of great significance for further understanding of the NsCIPK gene family function. [ABSTRACT FROM AUTHOR]

Nitraria sibirica is a shrub that can survive in extreme drought environments. The auxin-response factors (ARFs) are a class of transcription factors that are widely involved in plant growth and development, as well as in the regulation of stress resistance. However, the genome-wide identification of the ARF gene family and its responses to environmental stresses, especially drought stress, in N. sibirica has not yet been reported. Here, we identified a total of 12 ARF genes in the genome of N. sibirica, which were distributed over 10 chromosomes and divided into three clades. Intragenome synteny analysis revealed one collinear gene pair in the ARF gene family, i.e., NsARF9a and NsARF9b. Cis-acting element analysis showed that multiple hormones and stress-responsive cis-acting elements were found in the promoters of NsARFs, suggesting that NsARFs may be involved in multiple biological processes. Quantitative real-time PCR (qRT-PCR) showed that many NsARFs had tissue-specific expression patterns, with the highest expression of NsARF16 in the seedlings of N. sibirica. In addition, most of the NsARFs that were upregulated under drought were independent of endogenous ABA biosynthesis, whereas the response of NsARF5 and NsARF7a to drought was disrupted by the ABA-biosynthesis inhibitor fluridone. These studies provide a basis for further research into how NsARFs in N. sibirica respond to hormonal signaling and environmental stresses. [ABSTRACT FROM AUTHOR]

Bamboo is a natural fibre reinforced composite with excellent performance which is, to a certain extent, an alternative to the shortage of wood resources. The heterogeneous distribution and molecular structure of lignin is one of the factors that determines its performance, and it is the key and most difficult component in the basic research into the chemistry of bamboo and in bamboo processing and utilization. In this study, the distribution of lignin components and lignin content in micro-morphological regions were measured in semi-quantitative level by age and radial location by means of visible-light microspectrophotometry (VLMS) coupled with the Wiesner and Maule reaction. There as guaiacyl lignin and syringyl lignin in the cell wall of the fibre. Lignin content of the secondary cell wall and cell corner increased at about 10 days, reached a maximum at 1 year, and then decreased gradually. From 17 days to 4 years, the lignin content of the secondary cell wall in the outer part of bamboo is higher than that in the middle part (which is, in turn, higher than that in the inner part of the bamboo). VLSM results of the micro-morphological regions showed that bamboo lignification developed by aging. Guaiacyl and syringl lignin units can be found in the cell wall of the fibre, parenchyma, and vessel. There was a difference in lignin content among different ages, different radial location, and different micro-morphological regions of the cell wall. The fibre walls were rich in guaiacyl lignin in the early stage of lignification and rich in syringyl units in the later stage of lignification. The guaiacyl and syringyl lignin deposition of bamboo green was earlier than that of the middle part of bamboo culm, and that of the middle part of bamboo culm was earlier than that of bamboo yellow. The single molecule lignin content of the thin layer is higher than that of thick layers, while the primary wall is higher than the secondary cell wall, showing that lignin deposition is consistent with the rules of cell wall formation. The obtained cytological information is helpful to understand the origin of the anisotropic, physical, mechanical, chemical, and machining properties of bamboo. [ABSTRACT FROM AUTHOR]

Ubiquitination, an essential posttranslational modification, plays fundamental roles during mammalian spermatogenesis. We previously reported the requirement of two Cullin 4 ubiquitin ligase family genes, Cullin 4a (Cul4a) and Cullin 4b (Cul4b), in murine spermatogenesis. Both genes are required for male fertility despite their distinct functions in different cell populations. Cul4a is required in primary spermatocytes to promote meiosis while Cul4b is required in secondary spermatocytes for spermiogenesis. As the two genes encode proteins that are highly homologous and have overlapping expression in embryonic germ cells, they may compensate for each other during germ cell development. In the present study, we directly address the potential functional redundancy of these two proteins by deleting both Cul4 genes, specifically, in the germ cell lineage during embryonic development, using the germ-cell specific Vasa-Cre line. Conditional double-knockout (dKO) males showed delayed homing and impaired proliferation of gonocytes, and a complete loss of germ cells before the end of the first wave of spermatogenesis. The dKO male germ cell phenotype is much more severe than those observed in either single KO mutant, demonstrating the functional redundancy between the two CUL4 proteins. The dKO mutant also exhibited atypical tight junction structures, suggesting the potential involvement of CUL4 proteins in spermatogonial stem cell (SSC) niche formation and blood–testis-barrier (BTB) maintenance. We also show that deleting Cul4b in both germ and Sertoli cells is sufficient to recapitulate part of this phenotype, causing spermatogenesis defects and drastically reduced number of mature sperms, accompanied by defective tight junctions in the mutant testes. These results indicate the involvement of CUL4B in maintaining BTB integrity. [ABSTRACT FROM AUTHOR]

Aiming at the problems of a low material utilization rate and uneven stress distribution of cast-steel support joints in cable dome structures, topology optimization and additive manufacturing methods are used for optimization design and integrated manufacturing. First, the basic principle and calculation process of topology optimization are briefly introduced. Then, the initial model of the support joint is calculated and analyzed by using the universal software ANSYS Workbench 2020R2 and Altair OptiStruct, and the optimized joint is imported into Discovery Live to smooth the surface. The static behaviors of three types of joints (topology-optimized joints, joints after the smoothing treatment, and joints from practical engineering) are compared and analyzed. Finally, the joints are printed by using fused deposition modeling (FDM) technology and laser-based powder bed fusion (LBPBF) technology in additive manufacturing. The results show that the new support joint in the cable dome structure obtained by the topology optimization method has the advantages of a novel shape, a high material utilization rate, and a uniform stress distribution. Additive manufacturing technology can allow the manufacture of complex shape components with high precision and high speed. The combination of topology optimization and additive manufacturing effectively realizes the advanced design and integrated manufacturing of support joints for cable dome structures. [ABSTRACT FROM AUTHOR]

To allow extraction of irrigation signals from satellite-derived data on soil moisture, this study describes the development of an irrigation signal extraction method that takes into account multiple environmental factors in irrigation. Firstly, the fuzzy membership functions of irrigation relating to multiple environmental factors are constructed. Then, a model is built based on the fuzzy membership functions by using operation rules of fuzzy sets, which is used to infer the relevant degree of irrigation to nonirrigation. Finally, the irrigation signals in satellite-based soil moisture data are recognized according to the relevant degree. Taking Henan Province in the North China Plain as the study area, the proposed method is used to extract irrigation signals from the SMAP Level 3 Passive Soil Moisture Product. Extracted irrigation signals from two SMAP grids are validated using daily in situ soil moisture and precipitation data, with the results showing correct identification of most of the irrigation signals. By grading the membership degree of the extracted irrigation signals, irrigation frequency maps for the 2016–2017 winter crop growth season and the 2017 summer crop growth season are obtained for Henan Province. Compared to the irrigation frequency maps with data on the annual precipitation and the annual potential evapotranspiration, the irrigation frequency maps show a spatial pattern opposite that of the annual precipitation and a spatial pattern similar to that of the annual potential evapotranspiration. It is common sense that areas with low precipitation and high evapotranspiration need more irrigation frequency and irrigation water. Thus, the spatial patterns of irrigation frequency maps are reasonable in a sense. However, it should be noted that the observed irrigation data used in the qualitative assessments are rendered less convincing by the SMAP product's coarse resolution. Quantitative validation of extracted irrigation signals remains a significant challenge, and small-scale irrigation cannot be captured by coarse-resolution satellite-based soil moisture products. Thus, a high-resolution soil moisture product should be used to extract irrigation signals in future. [ABSTRACT FROM AUTHOR]

Nitraria tangutorum Bobrov is a halophyte that is resistant to salt and alkali and is widely distributed in northwestern China. However, its genome has not been sequenced, thereby limiting studies on this particular species. For species without a reference genome, the full-length transcriptome is a convenient and rapid way to obtain reference gene information. To better study N. tangutorum, we used PacBio single-molecule real-time technology to perform full-length transcriptome analysis of this halophyte. In this study, a total of 21.83 Gb of data were obtained, and 198,300 transcripts, 51,875 SSRs (simple sequence repeats), 55,574 CDS (coding sequence), and 74,913 lncRNAs (long non-coding RNA) were identified. In addition, using this full-length transcriptome, we identified the key Na+/H+ antiporter (NHX) genes that maintain ion balance in plants and found that these are induced to express under salt stress. The results indicate that the full-length transcriptome of N. tangutorum can be used as a database and be utilized in elucidating the salt tolerance mechanism of N. tangutorum. [ABSTRACT FROM AUTHOR]

This paper studies aligned glass fiber-reinforced composites for printing. To determine the influence of fiber content and alignment on the mechanical properties of this novel material, a large number of standard test specimens were prepared, which included samples fabricated by mold-casting, randomly dispersed fiber reinforced mixtures and aligned fiber cement composites containing 10 types of fiber volume ratios manufactured by nozzle sizes ranging of 24 and 10 mm (fiber length = 12 mm). Mechanical properties and failure modes of the specimens under compression and flexural tests were studied experimentally. The anisotropic behaviors of printed samples were analyzed by different loading directions. As a result, the compressive and flexural strength of printed samples showed obvious anisotropy. With the increase of fiber volume ratio, flexural strength of the fiber reinforced composite was elevated tremendously but its compression strength reduced slightly. Moreover, fiber alignment also had a significant influence on the mechanical properties of the fiber reinforced composite. The composite cement-based material with 1 vol.-% aligned fiber exhibited an excellent flexural strength of 9.38 MPa, which increased by 483% in comparison to that of the plain cement paste. [ABSTRACT FROM AUTHOR]

Prompted by rising concern about weak consumer switching and the practice of price discrimination, over the period of 2016–2019, the Office of Gas and Electricity Markets (Ofgem) undertook a series of trials on communication-based interventions to encourage consumer switching in the United Kingdom. The main purpose of this paper is to assess the experience of these Ofgem trials with a view to draw some lessons for policy makers. The analytical framework adopted for this purpose is informed by existing literature on the barriers for consumer switching. The results of the analysis suggest that while the Ofgem trials have made positive impacts on consumer switching, these impacts varied significantly across the trials, suggesting that some interventions were more effective than others. Further, the overall impacts of the Ofgem trials were moderate, as around 70% of participants did not switch suppliers even in the most impactful trial. This reflects a general lack of understanding in the literature about the behaviour-influencing factors, their impacts, and their context-connects. By implication, the difficulty in stimulating consumer switching, as demonstrated by the Ofgem trials, suggests that weak consumer switching and the practice of price discrimination may simply reflect significant competition, rather than a lack of it, especially if retail margins are not greater than the competitive level. In this case, the communication-based intervention aimed at encouraging consumer switching may lead to further price discrimination, especially for the most vulnerable consumers, who are more likely to stay with their incumbent suppliers. [ABSTRACT FROM AUTHOR]

In order to avoid the delamination of traditional tubular composite materials and reduce its woven cost, on an ordinary loom, the three-dimensional (3D) tubular woven fabrics were woven with basalt filament tows, and then the 3D tubular woven composites were prepared with epoxy resin by a hand layup process. The wall thickness of the 3D tubular woven composite was thin, and was only 2 mm thick. Through experiments and finite element method (FEM) simulation, the axial compression properties of the material were analyzed. The results show that the material 2 mm thick has good axial compression performance, the maximum load value of the experiment is 10,578 N, and the maximum load value of the finite element simulation is 11,285 N. The error between the two is 6.68%, indicating that the experiment and simulation have a good consistency. The failure mode of the material is also analyzed through finite element method simulation in the paper, thus revealing the failure stress propagation, local stress concentration, and failure morphology of the material. It provides an effective reference for the design and application of the 3D tubular woven composite. [ABSTRACT FROM AUTHOR]

Phytosulfokine-α (PSK-α) is a newly discovered short peptide that acts as a phytohormone in various plants. Previous studies have shown that PSK-α is critical for many biological processes in plants, such as cell division and differentiation, somatic embryogenesis, pollen germination and plant resistance. In this study, we cloned two PSK homolog genes from Cunninghamia lanceolata (Lamb.) Hook (Chinese fir), ClPSK1 and ClPSK2, and characterized their function in root development. Quantitative RT-PCR analyses showed that both ClPSK1 and ClPSK2 were expressed in vegetative organs, mainly in roots. Transgenic Arabidopsis plants overexpressing ClPSK1 or ClPSK2 showed a higher frequency of adventitious root formation and increased root length. The expression of genes in Arabidopsis that are involved in stem cell activity (PLT1, PLT2 and WOX5), radial organization of the root (SHR and SCR) and cell cycle (CYCB1;1, CYCD4;1, CDKB1;1 and RBR) were significantly up-regulated, which may contribute to the elongation of the primary root and the formation of adventitious root in transgenic lines. Our results suggest that ClPSKs play an important role during root growth and development. [ABSTRACT FROM AUTHOR]

Conventionally laminated spacer composites are extensively applied in many fields owing to their light weight. However, their impact resistance, interlaminar strength, and integrity are poor. In order to overcome these flaws, the zigzag-shaped 3D woven spacer composites were rationally designed. The zigzag-shaped 3D woven spacer fabrics with the basalt fiber filaments tows 400 tex (metric count of yarn) used as warp and weft yarns were fabricated on a common loom with low-cost processing. The zigzag-shaped 3D woven spacer composites were obtained using the VARTM (vacuum-assisted resin transfer molding) process. The three-point bending deformation and effects of damage in zigzag-shaped 3D woven spacer composites were studied both in experiment and using the finite element method (FEM). The bending properties of zigzag-shaped 3D woven spacer composites with different direction, different numbers of weaving cycle, and different heights were tested in experiments. In FEM simulation, the geometrical model was established to analyze the deformation and damage based on the 3D woven composite structure. Compared with data obtained from the experiments and FEM simulation, the results show good agreement and also prove the validity of the model. Based on the FEM results, the deformation, damage, and propagation of stress obtained from the model are very helpful in analyzing the failure mechanism of zigzag-shaped 3D woven composites. Furthermore, the results can significantly guide the fabrication process of real composite materials. [ABSTRACT FROM AUTHOR]