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Ensuring precise prediction of the remaining useful life (RUL) for bearings in rolling machinery is crucial for preventing sudden machine failures and optimizing equipment maintenance strategies. Since the significant interference encountered in real industrial environments and the high complexity of the machining process, accurate and robust RUL prediction of rolling bearings is of tremendous research importance. Hence, a novel RUL prediction model called CNN-VAE-MBiLSTM is proposed in this paper by integrating advantages of convolutional neural network (CNN), variational autoencoder (VAE), and multiple bi-directional long short-term memory (MBiLSTM). The proposed approach includes a CNN-VAE model and a MBiLSTM model. The CNN-VAE model performs well for automatically extracting low-dimensional features from time–frequency spectrum of multi-axis signals, which simplifies the construction of features and minimizes the subjective bias of designers. Based on these features, the MBiLSTM model achieves a commendable performance in the prediction of RUL for bearings, which independently captures sequential characteristics of features in each axis and further obtains differences among multi-axis features. The performance of the proposed approach is validated through an industrial case, and the result indicates that it exhibits a higher accuracy and a better anti-noise capacity in RUL predictions than comparable methods. [ABSTRACT FROM AUTHOR]

Haze or cloud always shrouds satellite images, obscuring valuable geographic information for military surveillance, natural calamity surveillance and mineral resource exploration. Satellite image dehazing (SID) provides the possibility for better applications of satellite images. Most of the existing dehazing methods are tailored for natural images and are not very effective for satellite images with non-homogeneous haze since the semantic structure information and inconsistent attenuation are not fully considered. To tackle this problem, this study proposes a hierarchical semantic-guided contextual structure-aware network (SCSNet) for spectral satellite image dehazing. Specifically, a hybrid CNN–Transformer architecture integrated with a hierarchical semantic guidance (HSG) module is presented to learn semantic structure information by synergetically complementing local representation from non-local features. Furthermore, a cross-layer fusion (CLF) module is specially designed to replace the traditional skip connection during the feature decoding stage so as to reinforce the attention to the spatial regions and feature channels with more serious attenuation. The results on the SateHaze1k, RS-Haze, and RSID datasets demonstrated that the proposed SCSNet can achieve effective dehazing and outperforms existing state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The insulated core transformer (ICT) power supply is widely employed in electron beam accelerators (EBAs) due to its high power, heightened efficiency, and stable operation. However, the segmented-core structure of the ICT power supply increases magnetic leakage, which leads to it adversely affecting the consistency of the output voltages in the rectifier stages. Currently, numerous studies focus on stage voltage compensation, including turns compensation, capacitor compensation, dummy primary winding compensation, and full-parameter compensation. This paper presents a unified simulation model and an improved gradient-based genetic algorithm, which can also optimize the parameters of the four compensation methods. Based on this, the performance of the power supply using the four compensation methods under different ICT energy levels and power supply requirements is studied, and the selection suggestions are given. This work fills the gap in the performance comparison and application research of various compensation methods. [ABSTRACT FROM AUTHOR]

Explosive shock wave protection is an important issue that urgently needs to be solved in the current military and public security safety fields. Non-metallic protective structures have the characteristics of being lightweight and having low secondary damage, making them an important research object in the field of equivalent protection. In this paper, the numerical simulation was performed to investigate the dynamic mechanical response of non-metallic annular protective structures under the internal blast, which were made by the continuous winding of PE fibers. The impact of various charges, the number of fiber layers, and polyurethane foam on the damage to protective structures was analyzed. The numerical results showed that 120 PE fiber layers could protect 50 g TNT equivalent explosives. However, solely increasing the thickness of fiber layers cannot effectively enhance the protection efficiency. By adding polyurethane foam in the inner layer, the stress acting on the fiber could be effectively reduced. A 30 mm thick polyurethane layer can reduce the equivalent stress of the fiber layer by 41.6%. This paper can provide some reference for the numerical simulations of non-metallic explosion protection structures. [ABSTRACT FROM AUTHOR]

Both parasitoids and entomopathogenic fungi are becoming increasingly crucial for managing pest populations. Therefore, it is essential to carefully consider the potential impact of entomopathogenic fungi on parasitoids due to their widespread pathogenicity and the possible overlap between these biological control tools during field applications. However, despite their importance, little research has been conducted on the pathogenicity of entomopathogenic fungi on parasitoids. In our study, we aimed to address this knowledge gap by investigating the interaction between the well-known entomopathogenic fungus Beauveria bassiana, and the pupal endoparasitoid Pteromalus puparum. Our results demonstrated that the presence of B. bassiana significantly affected the survival rates of P. puparum under laboratory conditions. The pathogenicity of B. bassiana on P. puparum was dose- and time-dependent, as determined via through surface spraying or oral ingestion. RNA-Seq analysis revealed that the immune system plays a primary and crucial role in defending against B. bassiana. Notably, several upregulated differentially expressed genes (DEGs) involved in the Toll and IMD pathways, which are key components of the insect immune system, and antimicrobial peptides were rapidly induced during both the early and late stages of infection. In contrast, a majority of genes involved in the activation of prophenoloxidase and antioxidant mechanisms were downregulated. Additionally, we identified downregulated DEGs related to cuticle formation, olfactory mechanisms, and detoxification processes. In summary, our study provides valuable insights into the interactions between P. puparum and B. bassiana, shedding light on the changes in gene expression during fungal infection. These findings have significant implications for the development of more effective and sustainable strategies for pest management in agriculture. [ABSTRACT FROM AUTHOR]

Background: Breast cancer is one of the most common malignant tumors in women. A noninvasive ultrasound examination can identify mammary-gland-related diseases and is well tolerated by dense breast, making it a preferred method for breast cancer screening and of significant clinical value. However, the diagnosis of breast nodules or masses via ultrasound is performed by a doctor in real time, which is time-consuming and subjective. Junior doctors are prone to missed diagnoses, especially in remote areas or grass-roots hospitals, due to limited medical resources and other factors, which bring great risks to a patient's health. Therefore, there is an urgent need to develop fast and accurate ultrasound image analysis algorithms to assist diagnoses. Methods: We propose a breast ultrasound image-based assisted-diagnosis method based on convolutional neural networks, which can effectively improve the diagnostic speed and the early screening rate of breast cancer. Our method consists of two stages: tumor recognition and tumor classification. (1) Attention-based semantic segmentation is used to identify the location and size of the tumor; (2) the identified nodules are cropped to construct a training dataset. Then, a convolutional neural network for the diagnosis of benign and malignant breast nodules is trained on this dataset. We collected 2057 images from 1131 patients as the training and validation dataset, and 100 images of the patients with accurate pathological criteria were used as the test dataset. Results: The experimental results based on this dataset show that the MIoU of tumor location recognition is 0.89 and the average accuracy of benign and malignant diagnoses is 97%. The diagnosis performance of the developed diagnostic system is basically consistent with that of senior doctors and is superior to that of junior doctors. In addition, we can provide the doctor with a preliminary diagnosis so that it can be diagnosed quickly. Conclusion: Our proposed method can effectively improve diagnostic speed and the early screening rate of breast cancer. The system provides a valuable aid for the ultrasonic diagnosis of breast cancer. [ABSTRACT FROM AUTHOR]

Insects employ multifaceted strategies to combat invading fungi, with immunity being a promising mechanism. Immune pathways function in signal transduction and amplification, ultimately leading to the activation of antimicrobial peptides (AMPs). Although several studies have shown that immune pathways are responsible for defending against fungi, the roles of parasitoid immune pathways involved in antifungal responses remain unknown. In this study, we evaluated the roles of the Toll and IMD pathways of a pupal parasitoid, Pteromalus puparum (Hymenoptera: Pteromalidae), in fighting against Beauveria bassiana (Hypocreales: Cordycipitaceae). Successful colonization of B. bassiana on P. puparum adults was confirmed by scanning electron microscopy (SEM). AMPs were induced upon B. bassiana infection. The knockdown of key genes, PpTollA and PpIMD, in Toll and IMD signaling pathways, respectively, significantly compromised insect defense against fungal infection. The knockdown of either PpTollA or PpIMD in P. puparum dramatically promoted the proliferation of B. bassiana, resulting in a decreased survival rate and downregulated expression levels of AMPs against B. bassiana compared to controls. These data indicated that PpTollA and PpIMD participate in Toll and IMD-mediated activation of antifungal responses, respectively. In summary, this study has greatly broadened our knowledge of the parasitoid antifungal immunity against fungi. [ABSTRACT FROM AUTHOR]

The development and utilization of urban underground space is an important way to solve the "great urban disease". As one of the most important types of urban underground foundations, utility tunnels have become increasingly popular in municipal construction. The investigation of utility tunnels is a general task and three-dimensional laser scanning technology has played a significant role in surveying and data acquisition. However, three-dimensional laser scanning technology suffers from noise and occlusion in narrow congested utility tunnel spaces, and the acquired point clouds are imperfect; hence, errors and redundancies are introduced in the extracted geometric elements. The topology of reconstructed BIM objects cannot be ensured. Therefore, in this study, a hierarchical segmentation method for point clouds and a topology reconstruction method for building information model (BIM) objects in utility tunnels are proposed. The point cloud is segmented into facades, planes, and pipelines hierarchically. An improved mean-shift algorithm is proposed to extract wall line features and a local symmetry-based medial axis extraction algorithm is proposed to extract pipelines from point clouds. A topology reconstruction method that searches for the neighbor information of wall and pipeline centerlines and establishes collinear, perpendicular, and intersecting situations is used to reconstruct a topologically consistent 3D model of a utility tunnel. An experiment on the Guangzhou's Nansha District dataset successfully reconstructed 24 BIM wall objects and 12 pipelines within the utility tunnel, verifying the efficiency of the method. [ABSTRACT FROM AUTHOR]

In the face of the current energy and environmental problems, the full use of biomass resources instead of fossil energy to produce a series of high-value chemicals has great application prospects. 5-hydroxymethylfurfural (HMF), which can be synthesized from lignocellulose as a raw material, is an important biological platform molecule. Its preparation and the catalytic oxidation of subsequent products have important research significance and practical value. In the actual production process, porous organic polymer (POP) catalysts are highly suitable for biomass catalytic conversion due to their high efficiency, low cost, good designability, and environmentally friendly features. Here, we briefly describe the application of various types of POPs (including COFs, PAFs, HCPs, and CMPs) in the preparation and catalytic conversion of HMF from lignocellulosic biomass and analyze the influence of the structural properties of catalysts on the catalytic performance. Finally, we summarize some challenges that POPs catalysts face in biomass catalytic conversion and prospect the important research directions in the future. This review provides valuable references for the efficient conversion of biomass resources into high-value chemicals in practical applications. [ABSTRACT FROM AUTHOR]

As an important food crop, summer maize is widely planted all over the world. Monitoring its growth and output is of great significance for world food security. With the trend of global warming and deterioration, the frequency of high temperature and heat damage affecting summer corn has been increasing in the past ten years. Therefore, there is an increasing demand for monitoring the high temperature and heat damage of summer maize. At present, there are nearly a hundred indices or methods for research on high temperature and heat damage. However, research based on the vegetation index cannot fully describe the damage caused by high-temperature thermal damage, and there is an obvious asynchrony effect. Research based on hyperspectral remote sensing has many inconveniences in data acquisition and complex physical model construction. Therefore, this study uses remote sensing data, including MODIS surface reflection data, MODIS land surface temperature products, as well as ground observation data and statistical data, combined with multiple remote sensing indices and land surface temperature, to construct a remote sensing index, LSHDI (land surface heat damage index). The LSHDI first searches for a location with the worst vegetation growth conditions in the three-dimensional feature space based on the LST (land surface temperature), the normalized difference vegetation index (NDVI), and the land surface water index (LSWI). Then, it calculates the distance between each point and this location to measure the degree of vegetation affected by high temperature and heat damage. Finally, because there is no reliable disaster verification dataset that has been published at present, this study uses soil moisture as a reference to explain the performance and stability of the LSHDI. The results showed that their coefficient of determination was above 0.5 and reached a significance level of 0.01. The LSHDI can well-reflect the high temperature and heat damage of land surface vegetation and can provide important data support and references for agricultural management departments. [ABSTRACT FROM AUTHOR]

Calcium carbonate (CaCO3) is a widely used inorganic powder, but its industrial applications are limited by its hydrophilicity and oleophobicity. Surface modification of CaCO3 can improve its dispersion and stability in organic materials and further improve its potential value. In this study, CaCO3 particles were modified with silane coupling agent (KH550) and titanate coupling agent (HY311) combined with ultrasonication. The oil absorption value (OAV), activation degree (AG), and sedimentation volume (SV) were employed to evaluate the modification performance. The results showed that the modification effect of HY311 on CaCO3 was better than that of KH550, and ultrasonic treatment played an auxiliary role. Based on response surface analysis, the optimal modification conditions were determined as follows: the HY311 dosage was 0.7%, the KH550 dosage was 0.7%, and ultrasonic time was 10 min. The OAV, AG, and SV of modified CaCO3 under these conditions were 16.65 g DOP/100 g, 99.27%, and 0.65 mL/g, respectively. The SEM, FTIR, XRD and thermal gravimetric analyses indicated successful coating of HY311 and KH550 coupling agents on the surface of CaCO3. The optimization of the dosages of two coupling agents and ultrasonic time improved the modification performance significantly. [ABSTRACT FROM AUTHOR]

Global navigation satellite system reflectometry (GNSS-R) is a remote sensing technology of soil moisture measurement using signals of opportunity from GNSS, which has the advantages of low cost, all-weather detection, and multi-platform application. An in situ GNSS-R and radiometer fusion soil moisture retrieval model based on LSTM (long–short term memory) is proposed to improve accuracy and robustness as to the impacts of vegetation cover and soil surface roughness. The Oceanpal GNSS-R data obtained from the experimental campaign at the Valencia Anchor Station are used as the main input data, and the TB (brightness temperature) and TR (soil roughness and vegetation integrated attenuation coefficient) outputs of the ELBARA-II radiometer are used as auxiliary input data, while field measurements with a Delta-T ML2x ThetaProbe soil moisture sensor were used for reference and validation. The results show that the LSTM model can be used to retrieve soil moisture, and that it performs better in the data fusion scenario with GNSS-R and radiometer. The STD of the multi-satellite fusion model is 0.013. Among the single-satellite models, PRN13, 20, and 32 gave the best retrieval results with STD = 0.011, 0.012, and 0.007, respectively. [ABSTRACT FROM AUTHOR]

miR-144/451 and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) regulate two antioxidative systems that have been identified to maintain redox homeostasis in erythroid cells by removing excess reactive oxygen species (ROS). Whether these two genes coordinate to affect ROS scavenging and the anemic phenotype, or which gene is more important for recovery from acute anemia, has not been explored. To address these questions, we crossed miR-144/451 knockout (KO) and Nrf2 KO mice and examined the phenotype change in the animals as well as the ROS levels in erythroid cells either at baseline or under stress condition. Several discoveries were made in this study. First, Nrf2/miR-144/451 double-KO mice unexpectedly exhibit similar anemic phenotypes as miR-144/451 single-KO mice during stable erythropoiesis, although compound mutations of miR-144/451 and Nrf2 lead to higher ROS levels in erythrocytes than single gene mutations. Second, Nrf2/miR-144/451 double-mutant mice exhibit more dramatic reticulocytosis than miR-144/451 or Nrf2 single-KO mice during days 3 to 7 after inducing acute hemolytic anemia using phenylhydrazine (PHZ), indicating a synergistic effect of miR-144/451 and Nrf2 on PHZ-induced stress erythropoiesis. However, the coordination does not persist during the whole recovery stage of PHZ-induced anemia; instead, Nrf2/miR-144/451 double-KO mice follow a recovery pattern similar to miR-144/451 single-KO mice during the remaining period of erythropoiesis. Third, the complete recovery from PHZ-induced acute anemia in miR-144/451 KO mice takes longer than in Nrf2 KO mice. Our findings demonstrate that complicated crosstalk between miR-144/451 and Nrf2 does exist and the crosstalk of these two antioxidant systems is development-stage-dependent. Our findings also demonstrate that miRNA deficiency could result in a more profound defect of erythropoiesis than dysfunctional transcription factors. [ABSTRACT FROM AUTHOR]

M50 bearing steel has great potential for applications in the field of aerospace engineering, as it exhibits outstanding mechanical and physical properties. From a microscopic point of view, bearing wear originates from the microscopic region of the contact interface, which usually only contains hundreds or even several atomic layers. However, the existing researches seldom study the wear of M50 bearing steel on the microscopic scale. This study explored the atomic-scale modeling method of M50 bearing steel. Then molecular dynamics simulations of nanoindentation on the M50 bearing steel model were carried out to study the size effect of the mechanical behaviors. The simulation results show that with the change in the radius of the diamond indenter in the nanoindentation simulation, the calculated nanohardness decreases. According to the size effect, when the indentation radius is 200 nm, the hardness obtained by the simulation is about 9.26 GPa, and that of the M50 sample measured by the nanoindentation is 10.4 GPa. Then nanoindentation simulations were carried out at different temperatures. The main bearings of aero-engines generally work at 300–500 degrees Celsius. When the simulated temperature was increased from 300 K to 800 K, the hardness of the model decreased by 15%, and the model was more prone to plastic deformation. In this study, a new molecular dynamics modeling method for M50 bearing steel was proposed, and then nanoindentation simulation was carried out, and the nanoindentation experiment verified the correctness of the model. These results are beneficial to the basic understanding of the mechanical performance of M50 bearing steel. [ABSTRACT FROM AUTHOR]

A series of four Werner-type complexes of Pd(II) and Pt(II) with planar, isomeric conjugated aromatic naphtoquinone oximes were synthesized for the first time. These ligands were 1-oxime-2-naphtoquinone (HL1) and 2-oxime-1-napthoquinone (HL2). Compounds were characterized using thermal analysis, spectroscopic methods, and X-ray analysis. TG/DSC data were collected for pure starting organic ligands, their complexes, and indicated vigorous exothermic decomposition with at ~155 °C for starting HL and ~350 °C for transition metal complexes. Crystal structures for two Pt compounds with 2-oxime-1-quinone were determined and revealed the formation of the cis-geometry complexes and incorporation of molecules of stoichiometric solvents in the lattice: acetonitrile and nitrobenzene. Both solvents of crystallization displayed attractive interactions between their C-H groups and the oxygen atoms of the nitroso groups in complexes, leading to short distances in those fragments. Despite the presence of solvents of inclusion, the overall structure motifs in both compounds represent 1D columnar coordination polymer, in which the PtL2 units are held together via metallophilic interactions, thereby forming 'Pt-wires'. The Hirshfield surface analysis was performed for both crystallographically characterized complexes. The results showed intermolecular π–π stacking and Pt–Pt interactions among the planar units of both complexes. In addition, the analysis also verified the presence of hydrogen bonding interactions between the platinum unit and solvent molecules. Solid bulk powdery samples of both PtL12 and PtL22 demonstrated pronounced photoluminescence in the near infrared region of spectrum at ~980 nm, being excited in the range of 750–800 nm. The NIR emission was observed only for Pt-complexes and not for pure starting organic ligands or Pd-complexes. Additionally, synthesized Pt-naphtoquinone oximes do not show luminescence in solutions, which suggests the importance of a 1D 'metal wire' structure for this process. [ABSTRACT FROM AUTHOR]

Various environmental factors and anthropogenic practices can affect the Fe biogeochemical cycles in soils. Nitrogen and carbon states are closely associated with Fe dynamics. However, we still have a limited understanding of the complex response of Fe biogeochemical processes to long–term nitrogen– and organic–fertilization regimes. This study investigated the Fe fraction and distribution, as well as the link between Fe and nitrogen/carbon, in bulk soil and in soil aggregates. The results showed that the long–term application of the nitrogen fertilizer increased the contents of water–soluble iron (Ws–Fe) and carbonate–bound iron (Ca–Fe) in the bulk soil and various sizes of aggregates, as well as the iron contents in soybeans. The decreased pH and enhanced Feammox reaction in response to the nitrogen–fertilizer treatments were responsible for the increase in the Ws–Fe and Ca–Fe fractions. By contrast, the long–term application of the organic fertilizer decreased the contents of Ws–Fe and Ca–Fe, while it increased the contents of Ox–Fe and Or–Fe. Moreover, the contents of Ox–Fe and Or–Fe were positively correlated with the organic–carbon contents in the micro–aggregates of 0.053–0.25 mm and <0.053 mm. These results indicated that the long–term use of the organic fertilizer encouraged Fe immobilization in organo–inorganic compounds. However, the application of the nitrogen fertilizer alleviated the Fe retention induced by the organic fertilizer. In conclusion, long–term nitrogen and organic fertilization have contrasting influences on the mineralogy and availability of Fe in soil. This study is useful for understanding the mechanism underlying the interaction between Fe and nitrogen/carbon, as well as Fe's phytoavailability in response to different fertilization practices in brown soil. [ABSTRACT FROM AUTHOR]

Biomass burning (BB) emits a large volume of trace gases and aerosols into the atmosphere, which can significantly affect the earth's radiative balance and climate and has negative impacts on air quality and even human health. In late June 2017, an intense BB case, dominated by forest and savanna fires, occurred in Siberia, and it affected the air quality of Northeast China through long-range transport. Here, multisatellite remote-sensing products and ground-based PM2.5 measurements are used to evaluate the influence of the Siberian smoky plume on Northeast China. The results show that the BB was intense at the early stage when the daily fire count and average fire radiative power exceeded 300 and 200 MW, respectively. The maximum daily fire count reached 1350 in Siberia, and the peak value of instantaneous fire radiative power was as high as 3091.5 MW. High concentrations of CO and aerosols were emitted into the atmosphere by the BB in Siberia. The maximum daily mean values of the CO column concentration and aerosol optical depth (AOD) increased by 3 × 1017 molec·cm2 and 0.5 compared with that during the initial BB stage. In addition, the BB released a large number of absorptive aerosols into the atmosphere, and the UV aerosol index (UVAI) increased by five times at the peak of the event in Siberia. Under the appropriate synoptic conditions and, combined with pyroconvection, the smoky plume was lifted into the upper air and transported to Northeast China, affecting the air quality of Northeast China. The daily mean values of CO concentration, AOD, and UVAI in Northeast China increased by 6 × 1017 molec·cm2, 0.5, and 1.4, respectively, after being affected. Moreover, the concentration of the surface PM2.5 in Northeast China approximately doubled after being affected by the plume. The results of this study indicate that the air quality of Northeast China can be significantly affected by Siberian BBs under favorable conditions. [ABSTRACT FROM AUTHOR]

Melt-cast explosive 2,4-dinitroanisole (DNAN) crystal and its cocrystals DNAN/1,3-dinitrobenzene (DNB) and DNAN/2-nitroaniline (NA) were used to identify the effects of cocrystallization on the crystal structure, non-covalent interactions, and melting points of the DNAN crystal through density functional theory and molecular dynamics. The components DNB and NA with subtle structure variations between the nitro group and amino group can significantly affect the non-covalent interactions, especially the π-π stacking and H-bonds, which can lead to different crystal stacking styles. The melting points of the DNAN crystal are decreased through the cocrystallization, which expands the utilization of the DNAN-based melt cast explosives. Our study deciphers the effects caused by the cocrystallization on the structure and properties of melt cast explosives and may help to design and optimize novel melt-cast explosives. [ABSTRACT FROM AUTHOR]

Messenger RNA (mRNA), which is composed of ribonucleotides that carry genetic information and direct protein synthesis, is transcribed from a strand of DNA as a template. On this basis, mRNA technology can take advantage of the body's own translation system to express proteins with multiple functions for the treatment of various diseases. Due to the advancement of mRNA synthesis and purification, modification and sequence optimization technologies, and the emerging lipid nanomaterials and other delivery systems, mRNA therapeutic regimens are becoming clinically feasible and exhibit significant reliability in mRNA stability, translation efficiency, and controlled immunogenicity. Lipid nanoparticles (LNPs), currently the leading non-viral delivery vehicles, have made many exciting advances in clinical translation as part of the COVID-19 vaccines and therefore have the potential to accelerate the clinical translation of gene drugs. Additionally, due to their small size, biocompatibility, and biodegradability, LNPs can effectively deliver nucleic acids into cells, which is particularly important for the current mRNA regimens. Therefore, the cutting-edge LNP@mRNA regimens hold great promise for cancer vaccines, infectious disease prevention, protein replacement therapy, gene editing, and rare disease treatment. To shed more lights on LNP@mRNA, this paper mainly discusses the rational of choosing LNPs as the non-viral vectors to deliver mRNA, the general rules for mRNA optimization and LNP preparation, and the various parameters affecting the delivery efficiency of LNP@mRNA, and finally summarizes the current research status as well as the current challenges. The latest research progress of LNPs in the treatment of other diseases such as oncological, cardiovascular, and infectious diseases is also given. Finally, the future applications and perspectives for LNP@mRNA are generally introduced. [ABSTRACT FROM AUTHOR]

Ballistic target recognition is of great significance for space attack and defense. The micro-motion features, which contain spatial and motion information, can be regarded as the foundation of the recognition of ballistic targets. To take full advantage of the micro-motion information of ballistic targets, this paper proposes a method based on feature fusion to recognize ballistic targets. The proposed method takes two types of data as input: the time–range (TR) map and the time–frequency (TF) spectrum. An improved feature extraction module based on 1D convolution and time self-attention is applied first to extract the multi-level features at each time instant and the global temporal information. Then, to efficiently fuse the features extracted from the TR map and TF spectrum, deep generalized canonical correlation analysis with center loss (DGCCA-CL) is proposed to transform the extracted features into a hidden space. The proposed DGCCA-CL possesses better performance in two aspects: small intra-class distance and compact representation, which is crucial to the fusion of multi-modality data. At last, the attention mechanism-based classifier which can adaptively focus on the important features is employed to give the target types. Experiment results show that the proposed method outperforms other network-based recognition methods. [ABSTRACT FROM AUTHOR]

Hypoxia is a common biological condition in many malignant solid tumors that plays an imperative role in regulating tumor growth and impacting the treatment's therapeutic effect. Therefore, the hypoxia assessment is of great significance in predicting tumor development and evaluating its prognosis. Among the plenty of existing tumor diagnosis techniques, magnetic resonance imaging (MRI) offers certain distinctive features, such as being free of ionizing radiation and providing images with a high spatial resolution. In this study, we develop a fluorescent traceable and hypoxia-sensitive T1-weighted MRI probe (Fe3O4-Met-Cy5.5) via conjugating notable hypoxia-sensitive metronidazole moiety and Cy5.5 dye with ultrasmall iron oxide (Fe3O4) nanoparticles. The results of in vitro and in vivo experiments show that Fe3O4-Met-Cy5.5 has excellent performance in relaxivity, biocompatibility, and hypoxia specificity. More importantly, the obvious signal enhancement in hypoxic areas indicates that the probe has great feasibility for sensing tumor hypoxia via T1-weighted MRI. These promising results may unlock the potential of Fe3O4 nanoparticles as T1-weighted contrast agents for the development of clinical hypoxia probes. [ABSTRACT FROM AUTHOR]

Background Understanding the transmission source, pattern, and mechanism of infectious diseases is essential for targeted prevention and control. Though it has been studied for many years, the detailed transmission patterns and drivers for the seasonal influenza epidemics in China remain elusive. Methods In this study, utilizing a suite of epidemiological and genetic approaches, we analyzed the updated province-level weekly influenza surveillance, sequence, climate, and demographic data between 1 April 2010 and 31 March 2018 from continental China, to characterize detailed transmission patterns and explore the potential initiating region and drivers of the seasonal influenza epidemics in China. Results An annual cycle for influenza A(H1N1)pdm09 and B and a semi-annual cycle for influenza A(H3N2) were confirmed. Overall, the seasonal influenza A(H3N2) virus caused more infection in China and dominated the summer season in the south. The summer season epidemics in southern China were likely initiated in the "Lingnan" region, which includes the three most southern provinces of Hainan, Guangxi, and Guangdong. Additionally, the regions in the south play more important seeding roles in maintaining the circulation of seasonal influenza in China. Though intense human mobility plays a role in the province-level transmission of influenza epidemics on a temporal scale, climate factors drive the spread of influenza epidemics on both the spatial and temporal scales. Conclusion The surveillance of seasonal influenza in the south, especially the "Lingnan" region in the summer, should be strengthened. More broadly, both the socioeconomic and climate factors contribute to the transmission of seasonal influenza in China. The patterns and mechanisms revealed in this study shed light on the precise forecasting, prevention, and control of seasonal influenza in China and worldwide. [ABSTRACT FROM AUTHOR]

Scientometric reviews, facilitated by computational and visual analytical approaches, allow researchers to gain a thorough understanding of research trends and areas of concentration from a large number of publications. With the fast development of satellite altimetry, which has been effectively applied to a wide range of research topics, it is timely to summarize the scientific achievements of the previous 50 years and identify future trends in this field. A comprehensive overview of satellite altimetry was presented using a total of 8541 publications from the Web of Science Core Collection covering the years from 1970 to 2021. We begin by presenting the fundamental statistical results of the publications, such as the annual number of papers, study categories, countries/regions, afflictions, journals, authors, and keywords, in order to provide a comprehensive picture of satellite altimetry research. We discuss the co-occurrence of the authors in order to reveal the global collaboration network of satellite altimetry research. Finally, we utilised co-citation networks to detect the development trend and associated crucial publications for various specific topics. The findings show that satellite altimetry research has been changed immensely during the last half-century. The United States, France, China, England, and Germany made the most significant contributions in the field of satellite altimetry. The analysis reveals a clear link between technology advancements and the trend in satellite altimetry research. As a result, wide swath altimetry, GNSS-reflectometry, laser altimetry, terrestrial hydrology, and deep learning are among the most frontier study subjects. The findings of this work could guide a thorough understanding of satellite altimetry's overall development and research front. [ABSTRACT FROM AUTHOR]

Biomass burning (BB) is a driving force for heavy haze in northeastern China (NEC) and shows distinct seasonal features. However, little is known about its climatological aspects, which are important for regional BB management and understanding BB effects on climate and environment. Here, the climatological characteristics of active fires and their dependence on land cover in NEC were studied using Moderate Resolution Imaging Spectroradiometer (MODIS) products. Moreover, the influence of meteorological factors on fire activities was explored. The number of fires was found to have increased significantly from 2003 to 2018; and the annual total FRP (FRPtot) showed a generally consistent variation with fire counts. However, the mean fire radiative power for each spot (FRPmean) decreased. Fire activity showed distinctive seasonal variations. Most fires and intense burning events occurred in spring and autumn. Spatially, fires were mainly concentrated in cropland areas in plains, where the frequency of fires increased significantly, especially in spring and autumn. The annual percentage of agricultural fires increased from 34% in 2003 to over 60% after 2008 and the FRPtot of croplands increased from 12% to over 55%. Fires in forests, savannas, and grasslands tended to be associated with higher FRPmean than those in croplands. Analysis indicated that the increasing fire count in NEC is mainly caused by agricultural fires. Although the decreasing FRPmean represents an effective management of BB in recent years, high fire counts and FRPtot in croplands indicate that the crop residue burning cannot be simply banned and a need instead for effective applications. More efforts should be made on clean utilization of straw. The accumulation of dry biomass, high temperature, and low humidity, and weak precipitation are conducive to the fire activities. This study provides a comprehensive analysis of BB in NEC and provides a reference for regional BB management and control. [ABSTRACT FROM AUTHOR]

Simple Summary: Parasitoids are one of the most important biological control agents, and there are increasing requirements for long-term breeding. It is critical to figure out the parasitoid biological properties and disclose the effects of cold storage on them to extend their longevity. In this study, we investigated the field parasitism rate and clarified the biological parameters of Microplitis manilae, a dominant larval parasitoid of Spodoptera frugiperda. Further analysis revealed that the pupal cold storage, including different storage temperatures, storage period and storage time, significantly affected the emergence rate, parasitism rate and longevity of wasp adults, and the optimal storage condition was middle-aged pupae stored at 10 °C for 5–10 d. These results provide a novel insight into the mass-rearing of M. manilae and contribute to the biological control using M. manilae against S. frugiperda. As a major invasive pest in China, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) has caused great damage to crops. Hymenopteran parasitoids, especially the braconid wasps, play crucial roles in depressing pest populations. However, there was little information about the ideal storage of parasitoids to achieve their mass-rearing. Here, we identified a dominant parasitoid of S. frugiperda, Microplitis manilae (Ashmead) (Hymenoptera: Braconidae), in the Hainan province of China with a field parasitism rate of 5.66–19.10%. The investigation of biological parameters revealed that the parasitism rate of M. manilae significantly decreased with an increase in both wasp adult longevity and host age, and the wasp of 1–3 d post eclosion performed best on the first instar of host larvae, showing the highest parasitism rate. We also discovered that the decreased temperature from 30 to 20 °C greatly extended the longevity of wasp adults, and a similar result was observed after feeding on 10% sucrose water compared with sterile water. Then, the effects of different pupal cold storage temperatures (4 and 10 °C), storage period (prepupa, middle-aged pupa, late-aged pupa) and storage time (5, 10 or 20 d) on the emergence rate, parasitism rate, female proportion and longevity of M. manilae were investigated. The results demonstrated that the middle-aged wasp pupae stored at 10 °C for 5–10 d possessed a stronger parasitic ability and longer longevity. These findings may promote the flexibility and efficacy of large-scale production of M. manilae, thus contributing to its biological field control against S. frugiperda. [ABSTRACT FROM AUTHOR]

Chinese Yellow Cattle, an ancient and domesticated breed for draft service, provide unique animal genetic resources with excellent genetic features, including crude feed tolerance, good stress resistance, strong adaptability, and tender meat quality; however, their production performance and meat yield are significantly inferior. Herein, the myostatin gene (MSTN), a negative regulator of skeletal muscle development, was knocked out by CRISPR/Cas9 technology. Eight MSTN gene-edited bull calves (MT) were born, and six of them are well-developed. Compared with the control cattle (WT), the growth trait indexes of MT cattle were generally increased, and the hindquarters especially were significantly improved. The biochemical indexes and the semen characteristics demonstrated that MT bulls were healthy and fertile. Consistent with our conjecture, the wobble and beating of MT bull spermatozoa were significantly higher than that of WT. Nine sperm motility-related proteins and nineteen mitochondrial-related proteins were identified by up-regulation in MT bull spermatozoa using FLQ proteomic technique and act to govern sperm flagellum assembly, organization, and beating and provide sufficient energy for sperm motility. The current study confirmed that the MSTN gene-edited Chinese Yellow cattle have improved growth traits and normal fertility, which can be used for beef cattle production and breeding. [ABSTRACT FROM AUTHOR]

The dc-link voltage ripple plays an important role in dc capacitor design for three-phase voltage source converters (VSCs). However, the analytical models of the dc-link voltage ripple have rarely been reported for VSCs with nonlinear output current. This paper first derived the LOH voltages expressions in the dc-link. It reveals that each LOH component in ac current would induce two dc-link LOH voltages. Then the switching frequency harmonic voltages (SHVs) and their envelope expressions are formulated. Moreover, the proposed analytical models could be very much simplified when applied to special cases in the previous literature. Finally, an easy to design dc capacitor equation under nonlinear output current is also derived. Both simulation and experimental results validate the proposed method. [ABSTRACT FROM AUTHOR]

Tailings from gold mines gradually approach ultra-fine, making mine backfill costs higher and strength lower, which poses a serious threat to the safety of underground personnel and equipment. It is well known that suitable chemical admixtures can enhance the working properties of mortar materials. Therefore, in order to achieve the purpose of reducing the cost of ultra-fine tailings backfill and improving the working performance of ultra-fine tailings filling slurry, this paper provides a study on the effect of sodium silicate and calcium chloride on the properties of ultra-fine tailings cemented backfill materials. The results of experimental studies through rheology, strength, and microstructural tests, etc., showed that the optimal proportioning parameters of cementitious materials are 76.92% blast furnace slag, 19.24% carbide slag, and admixtures of 2.88% sodium silicate and 0.96% calcium chloride. The 3, 7, and 28-day uniaxial compressive strength of the ultra-fine tailings cemented paste backfill with the newly formulated blast furnace slag-based cementitious material increased by 124%, 142%, and 14%, respectively, compared to that of the ultra-fine tailings cemented paste backfill with the P. O42.5 cement. The setting time for ultra-fine tailings cemented backfill slurry is shortened by the addition of admixtures, and the shear stress of the slurry is correlated with the amount of hydration product generation and its formation of flocculating structure. Moreover, the cost of the newly prepared cementitious material is much lower than that of traditional cement, which lays a good foundation for the cemented filling of ultra-fine tailings. [ABSTRACT FROM AUTHOR]

Automatic fall detection plays a significant role in monitoring the health of senior citizens. In particular, millimeter-wave radar sensors are relevant for human pose recognition in an indoor environment due to their advantages of privacy protection, low hardware cost, and wide range of working conditions. However, low-quality point clouds from 4D radar diminish the reliability of fall detection. To improve the detection accuracy, conventional methods utilize more costly hardware. In this study, we propose a model that can provide high-quality three-dimensional point cloud images of the human body at a low cost. To improve the accuracy and effectiveness of fall detection, a system that extracts distribution features through small radar antenna arrays is developed. The proposed system achieved 99.1% and 98.9% accuracy on test datasets pertaining to new subjects and new environments, respectively. [ABSTRACT FROM AUTHOR]

Over the past four decades, Arctic sea ice coverage has steadily declined. This loss of sea ice has amplified solar radiation and heat absorption from the ocean, exacerbating both polar ice loss and global warming. It has also accelerated changes in sea ice movement, posing safety risks for ship navigation. In recent years, numerical prediction models have dominated the field of sea ice movement prediction. However, these models often rely on extensive data sources, which can be limited in specific time periods or regions, reducing their applicability. This study introduces a novel approach for predicting Arctic sea ice motion within a 10-day window. We employ a Self-Attention ConvLSTM deep learning network based on single-source data, specifically optical flow derived from the Advanced Microwave Scanning Radiometer Earth Observing System 36.5 GHz data, covering the entire Arctic region. Upon verification, our method shows a reduction of 0.80 to 1.18 km in average mean absolute error over a 10-day period when compared to ConvLSTM, demonstrating its improved ability to capture the spatiotemporal correlation of sea ice motion vector fields and provide accurate predictions. [ABSTRACT FROM AUTHOR]

Simple Summary: The study described the effects of Myostatin gene editing on cattle to improve the growth and muscle development of hybrid cattle offspring. We focused on the Myostatin gene, which plays a crucial role in regulating muscle development. Gene editing could be able to enhance the size and performance of the crossbred cattle. The results showed that the Myostatin gene-edited cattle offspring displayed improved body size parameters, particularly body weight, cross height, and hip height, indicating the significant development of the hindquarters. The edited cattle have "double-muscled" forequarters and hindquarters with clear muscle masses, and their coat color reverted back to the original yellow. The study also found differences in blood glucose, calcium, and low-density lipoprotein levels, as well as a decrease in serum insulin levels in the edited cattle. Overall, the findings suggest that breeding with these Myostatin gene-edited bulls improve growth and performance in crossbred cattle, benefiting both farmers and consumers. (1) Background: Myostatin (MSTN) is a protein that regulates skeletal muscle development and plays a crucial role in maintaining animal body composition and muscle structure. The loss-of-function mutation of MSTN gene can induce the muscle hypertrophic phenotype. (2) Methods: Growth indexes and blood parameters of the cattle of different months were analyzed via multiple linear regression. (3) Results: Compared with the control group, the body shape parameters of F2 cattle were improved, especially the body weight, cross height, and hip height, representing significant development of hindquarters, and the coat color of the F2 generation returned to the yellow of Luxi cattle. As adults, MSTN gene-edited bulls have a tall, wide acromion and a deep, wide chest. Both the forequarters and hindquarters are double-muscled with clear muscle masses. The multiple linear regression demonstrates that MSTN gene-edited hybrid beef cattle gained weight due to the higher height of the hindquarters. Significant differences in blood glucose, calcium, and low-density lipoprotein. Serum insulin levels decreased significantly at 24 months of age. MSTN gene editing improves the adaptability of cattle. (4) Conclusions: Our findings suggest that breeding with MSTN gene-edited Luxi bulls can improve the growth and performance of hybrid cattle, with potential benefits for both farmers and consumers. [ABSTRACT FROM AUTHOR]

Continuing efforts to develop novel smart materials are anticipated to upgrade the quality of life of humans. Thermo-responsive poly(N-isopropylacrylamide) and glucose-responsive phenylboronic acid--typical representatives--are often integrated as multi-stimuli-sensitive materials, but few are available for side-by-side comparisons with their properties. In this study, both copolymers bearing N-isopropylacrylamide (NIPAAm), with or without 3-acrylamidophenylboronic acid (AAPBA), were synthesized by free radical polymerization, and characterized by Fourier transform infrared spectrometry, nuclear magnetic resonance hydrogen spectroscopy and gel permeation chromatography. Dynamic light scattering was used to analyze and compare the responsive behaviors of the copolymers in different aqueous solutions. Atomic force microscopy was also employed to investigate the apparent morphology changes with particle sizes. The results demonstrated that the introduction of NIPAAm endowed the composite materials with thermosensitivity, whereas the addition of AAPBA lowered the molecular weight of the copolymers, intensified the intermolecular aggregation of the nanoparticles, reduced the lower critical solution temperature (LCST) of the composites, and accordingly allowed the copolymers to respond to glucose. It was also concluded that the responding of smart copolymers to operating parameters can be activated only under special conditions, and copolymer dimension and conformation were affected by inter/intramolecular interactions. [ABSTRACT FROM AUTHOR]

Synthetic Aperture Radar (SAR) imaging with a non-zero (forward) squint angle is capable of providing a longer time for reaction than that of the broadside mode. However, due to the large squint angle, there will be severe coupling between range and azimuth samples in the echoed data, which is known as the problematic Range Cell Migration (RCM) in the SAR community. Especially when the SAR sensor mounted on an airborne platform encounters unexpected motion deviations/errors, the coupling becomes more complicated, and it is difficult to differentiate the systematic RCM for the SAR Image Formation Processing (IFP) and the non-systematic RCM error to be compensated. To this end, a novel and accurate SAR imaging algorithm is proposed in this paper to facilitate the processing of airborne SAR data collected at a high-squint angle. Firstly, the proposed algorithm is established under a Fast Time-Domain Back-Projection (FTDBP) framework for the SAR IFP. FTDBP paves the way to avoid the complicated processing for the systematic RCM as for the conventional SAR IFP in the Doppler processing manner. It is capable of generating a high-resolution SAR image efficiently under more general geometries and configurations. Secondly, regarding the non-systematic RCM errors, the proposed algorithm realizes the compensation by correcting both the Non-systematic Range Cell Migration (NsRCM), as well as Azimuthal Phase Error (APE) in a coherent manner. It is consequently capable of auto-calibrating the effects of the motion error completely without being dependent on the airborne navigation unit. Finally, both simulated and raw data collected by the airborne squinted SAR are applied to evaluate the proposed algorithm. Comparisons with conventional algorithms are carried out to reveal the superiority of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Various plant species contain terpene secondary metabolites, which disrupt insect growth and development by affecting the activity of juvenile hormone-degrading enzymes, and the juvenile hormone (JH) titers maintained in insects. Nerolidol, a natural sesquiterpenol belonging to the terpenoid group, exhibits structural similarities to insect JHs. However, the impact of nerolidol on insect growth and development, as well as its underlying molecular mechanism, remains unclear. Here, the effects of nerolidol on Spodoptera exigua were investigated under treatment at various sub-lethal doses (4.0 mg/mL, 1.0 mg/mL, 0.25 mg/mL). We found that a higher dose (4.0 mg/mL) of nerolidol significantly impaired the normal growth, development, and population reproduction of S. exigua, although a relatively lower dose (0.25 mg/mL) of nerolidol had no significant effect on this growth and development. Combined transcriptome sequencing and gene family analysis further revealed that four juvenile hormone esterase (JHE)-family genes that are involved in juvenile hormone degradation were significantly altered in S. exigua larvae after nerolidol treatment (4.0 mg/mL). Interestingly, the juvenile hormone esterase-like (JHEL) gene Sexi006721, a critical element responsive to nerolidol stress, was closely linked with the significant augmentation of JHE activity and JH titer in S. exigua (R2 = 0.94, p < 0.01). Taken together, we speculate that nerolidol can function as an analog of JH by modulating the expression of the enzyme genes responsible for degrading JH, resulting in JH disorders and ultimately disrupting the development of insect larvae. This study ultimately provides a theoretical basis for the sustainable control of S. exigua in the field whilst proposing a new perspective for the development of novel biological pesticides. [ABSTRACT FROM AUTHOR]

Skin interstitial fluid (ISF) has emerged as a fungible biofluid sample for blood serum and plasma for disease diagnosis and therapy. The sampling of skin ISF is highly desirable considering its easy accessibility, no damage to blood vessels, and reduced risk of infection. Particularly, skin ISF can be sampled using microneedle (MN)-based platforms in the skin tissues, which exhibit multiple advantages including minimal invasion of the skin tissues, less pain, ease of carrying, capacity for continuous monitoring, etc. In this review, we focus on the current development of microneedle-integrated transdermal sensors for collecting ISF and detecting specific disease biomarkers. Firstly, we discussed and classified microneedles according to their structural design, including solid MNs, hollow MNs, porous MNs, and coated MNs. Subsequently, we elaborate on the construction of MN-integrated sensors for metabolic analysis with highlights on the electrochemical, fluorescent, chemical chromogenic, immunodiagnostic, and molecular diagnostic MN-integrated sensors. Finally, we discuss the current challenges and future direction for developing MN-based platforms for ISF extraction and sensing applications. [ABSTRACT FROM AUTHOR]

The rational design of interfacial contacts plays a decisive role in improving interfacial carrier transfer and separation in heterojunction photocatalysts. In Z-scheme photocatalysts, the recombination of photogenerated electron–hole pairs is prevented so that the redox capacity is maintained. Here, one-dimensional graphitic carbon nitride (g-C3N4)/CoFe2O4 fibres were synthesised as a new type of magnetic Z-scheme visible-light photocatalyst. Compared with pure g-C3N4 and CoFe2O4, the prepared composite photocatalysts showed considerably improved performance for the photooxidative degradation of tetracycline and methylene blue. In particular, the photodegradation efficiency of the g-C3N4/CoFe2O4 fibres for methylene blue was approximately two and seven times those of g-C3N4 and CoFe2O4, respectively. The formation mechanism of the Z-scheme heterojunctions in the g-C3N4/CoFe2O4 fibres was investigated using photocurrent spectroscopy and electrochemical impedance spectroscopy. We proposed that one of the reasons for the improved photodegradation performance is that the charge transport path in one-dimensional materials enables efficient photoelectron and hole transfer. Furthermore, the internal electric field of the prepared Z-scheme photocatalyst enhanced visible-light absorption, which provided a barrier for photoelectron–hole pair recombination. [ABSTRACT FROM AUTHOR]

The integration of global navigation satellite system (GNSS) precise point positioning (PPP) and inertial navigation system (INS) is widely used in navigation for its robustness and resilience, especially in case of GNSS signal blockage. With GNSS modernization, a variety of PPP models have been developed and studied, which has also led to various PPP/INS integration methods. In this study, we investigated the performance of a real-time GPS/Galileo zero-difference ionosphere-free (IF) PPP/INS integration with the application of uncombined bias products. This uncombined bias correction was independent of PPP modeling on the user side and also enabled carrier phase ambiguity resolution (AR). CNES (Centre National d'Etudes Spatiales) real-time orbit, clock, and uncombined bias products were used. Six positioning modes were evaluated, including PPP, PPP/INS loosely coupled integration (LCI), PPP/INS tightly coupled integration (TCI), and three of these with uncombined bias correction through a train positioning test in an open sky environment and two van positioning tests at a complex road and city center. All of the tests used a tactical-grade inertial measurement unit (IMU). In the train test, we found that ambiguity-float PPP had almost identical performance with LCI and TCI, which reached an accuracy of 8.5, 5.7, and 4.9 cm in the north (N), east (E) and up (U) direction, respectively. After AR, significant improvements on the east error component were achieved, which were 47%, 40%, and 38% for PPP-AR, PPP-AR/INS LCI, and PPP-AR/INS TCI, respectively. In the van tests, frequent signal interruptions due to bridges, vegetation, and city canyons make the IF AR difficult. TCI achieved the highest accuracies, which were 32, 29, and 41 cm for the N/E/U component, respectively, and also effectively eliminated the solution re-convergence in PPP. [ABSTRACT FROM AUTHOR]

To better understand the phenotypic plasticity of the highly invasive native weed, Pedicularis kansuensis, we investigated and compared phenotypes (morphology, biomass, and nutrient composition) at different levels of invasion (low: 0 < cover ≤ 30%; medium: 30% < cover ≤ 70%; and high: cover > 70%). With the increase in invasion level, the plasticity of inflorescence length, single-leaf thickness, and specific leaf area increased, while the plasticity of single-leaf area and crown width decreased. During the invasion process, we observed significant density-dependent effects, including changed morphological characteristics, increased total aboveground biomass, and decreased plant height, inflorescence length, root length, crown width, single-leaf area, structure biomass of structures (root, stem, inflorescence), and individual biomass (p < 0.05). During the reproductive period of P. kansuensis, the resource allocation (C, N, and P content, total biomass, biomass allocation) to inflorescence was significantly higher than to root and stem, while the elemental ratios (C:N, C:P, N:P) of inflorescences were significantly lower than those of roots and stems (p < 0.05). When the invasion level increased, the ratio of inflorescence C:N and biomass allocation to roots increased significantly; conversely, inflorescence N and biomass allocation to inflorescences and stems decreased significantly (p < 0.05). This led to a decrease in resource allocation to aboveground parts and more resources allocated to the roots, significantly increasing the root-to-shoot ratio (p < 0.05). Based on the phenotypic differences among different invasion levels, we suggest that P. kansuensis adapted to a competitive environment by regulating morphology, biomass, and nutrient allocation, thereby enhancing the potential of invasion and spread. [ABSTRACT FROM AUTHOR]

Simple Summary: The interactions between parasitoids and their host have always attracted much attention, and parasitoids manipulate the host physiology to benefit the survival and development of their offspring. It is critical to analyze these physiological regulatory mechanisms. In this study, using RNA-sequencing analysis, we clarified the effects of parasitization on host gene expression of Microplitis manilae, a dominant larval parasitoid of Spodoptera frugiperda. Several differentially expressed genes were identified in S. frugiperda larvae at 2 h, 24 h, and 48 h post-parasitization. Among these, many genes were implicated in host metabolism and immunity. Further qPCR results involving 20 differentially expressed metabolism, and immune-related genes were consistent with the expression profiles of the RNA-seq data, which confirmed the physiological manipulation of M. manilae on host S. frugiperda. These results contribute to defining the molecular basis of wasps' successful parasitization and facilitate their application. It has been extensively found that parasitoids manipulate host physiology to benefit the survival and development of their offspring. However, the underlying regulatory mechanisms have not received much attention. To reveal the effects of parasitization of the larval solitary endoparasitoid Microplitis manilae (Hymenoptera: Braconidae) on host Spodoptera frugiperda (Lepidoptera: Noctuidae), one of the most destructive agricultural pests in China, deep-sequencing-based transcriptome analysis was conducted to compare the host gene expression levels after 2 h, 24 h, and 48 h parasitization. A total of 1861, 962, and 108 differentially expressed genes (DEGs) were obtained from the S. frugiperda larvae at 2 h, 24 h, and 48 h post-parasitization, respectively, compared with unparasitized controls. The changes in host gene expressions were most likely caused by the injection of wasp parasitic factors, including PDVs, that were injected along with the eggs during oviposition. Based on the functional annotations in GO and KEGG databases, we revealed that most DEGs were implicated in host metabolism and immunity. Further analysis of the common DEGs in three comparisons between the unparasitized and parasitized groups identified four genes, including one unknown and three prophenoloxidase (PPO) genes. Moreover, 46 and 7 common DEGs involved in host metabolism and immunity were identified at two or three time points after parasitization, respectively. Among these, most DEGs showed increased expressions at 2 h post-wasp parasitization while exhibiting significantly decreased expression levels at 24 h post-parasitization, demonstrating the expression regulations of M. manilae parasitization on host metabolism and immune-related genes. Further qPCR verification in 20 randomly selected DEGs confirmed the accuracy and reproducibility of the gene expression profiles generated from RNA-seq. This study reveals the molecular regulatory network about how host insects respond to wasp parasitism, laying a solid foundation for revealing the physiological manipulation of wasp parasitization on host insects, which facilitates the development of biological control practices for parasitoids. [ABSTRACT FROM AUTHOR]

WRKY, named for its special heptapeptide conserved sequence WRKYGOK, is one of the largest transcription factor families in plants and is widely involved in plant responses to biotic, abiotic, and hormonal stresses, especially the important regulatory function in response to drought stress. However, there is no complete comprehensive analysis of this family in H. perforatum, which is one of the most extensively studied plants and is probably the best-known herbal medicine on the market today, serving as an antidepressant, neuroprotective, an antineuralgic, and an antiviral. Here, we identified 86 HpWRKY genes according to the whole genome database of H. perforatum, and classified them into three groups through phylogenetic analysis. Gene structure, conserved domain, motif, cis-elements, gene ontology, and expression profiling were performed. Furthermore, it was found that HpWRKY85, a homologous gene of AtWRKY75, showed obvious responses to drought treatment. Subcellular localization analysis indicated that this protein was localized in the nucleus by the Arabidopsis protoplasts transient transfection. Meanwhile, HpWRKY85-overexpressing Arabidopsis plants showed a stronger ability of root growth and scavenging endogenous reactive oxygen species. The results provide a reference for further understanding the role of HpWRKY85 in the molecular mechanism of drought resistance of H. perforatum. [ABSTRACT FROM AUTHOR]

The future of mobile communication systems is evolving rapidly toward being more intelligent, while also having the ability to interconnect with everything and be aware of the current wireless environment. For complex scenarios, the asymmetry features of channel state information (CSI) will seriously restrict the performance of the communication system. With its accurate positioning technology and high-speed communication rate, ultra-wideband (UWB) has a promising future as a solution to integrate communication and positioning functions. The traditional CSI channel estimation usually requires channel training, which will greatly increase the overhead of the system. This paper proposes a location information-assisted beamforming to replace the traditional channel training process. First, we use the user location parameter information to reconstruct the channel model and derive the CSI error distribution based on the location distribution. Second, considering the uncertainty of the user positioning error, we model the robust beamforming optimization problem that minimizes the total transmit power. To solve this non-convex problem effectively, we design a new beamforming algorithm by using semidefinite relaxation (SDR) and Bernstein-type inequalities. Finally, simulation results verify the robustness of the proposed robust beamforming compared to the worst-case robust beamforming. [ABSTRACT FROM AUTHOR]

This paper describes an automatic mosaicking algorithm for creating large-scale mosaic maps of forest height. In contrast to existing mosaicking approaches through using SAR backscatter power and/or InSAR phase, this paper utilizes the forest height estimates that are inverted from spaceborne repeat-pass cross-pol InSAR correlation magnitude. By using repeat-pass InSAR correlation measurements that are dominated by temporal decorrelation, it has been shown that a simplified inversion approach can be utilized to create a height-sensitive measure over the whole interferometric scene, where two scene-wide fitting parameters are able to characterize the mean behavior of the random motion and dielectric changes of the volume scatterers within the scene. In order to combine these single-scene results into a mosaic, a matrix formulation is used with nonlinear least squares and observations in adjacent-scene overlap areas to create a self-consistent estimate of forest height over the larger region. This automated mosaicking method has the benefit of suppressing the global fitting error and, thus, mitigating the "wallpapering" problem in the manual mosaicking process. The algorithm is validated over the U.S. state of Maine by using InSAR correlation magnitude data from ALOS/PALSAR and comparing the inverted forest height with Laser Vegetation Imaging Sensor (LVIS) height and National Biomass and Carbon Dataset (NBCD) basal area weighted (BAW) height. This paper serves as a companion work to previously demonstrated results, the combination of which is meant to be an observational prototype for NASA's DESDynI-R (now called NISAR) and JAXA's ALOS-2 satellite missions. [ABSTRACT FROM AUTHOR]

This paper describes a novel, simple and efficient approach to estimate forest height over a wide region utilizing spaceborne repeat-pass InSAR correlation magnitude data at L-band. We start from a semi-empirical modification of the RVoG model that characterizes repeat-pass InSAR correlation with large temporal baselines (e.g., 46 days for ALOS) by taking account of the temporal change effect of dielectric fluctuation and random motion of scatterers. By assuming (1) the temporal change parameters and forest backscatter profile/extinction coefficient follow some mean behavior across each inteferogram; (2) there is minimal ground scattering contribution for HV-polarization; and (3) the vertical wavenumber is small, a simplified inversion approach is developed to link the observed HV-polarized InSAR correlation magnitude to forest height and validated using ALOS/PALSAR repeat-pass observations against LVIS lidar heights over the Howland Research Forest in central Maine, US (with RMSE < 4 m at a resolution of 32 hectares). The model parameters derived from this supervised regression are used as the basis for propagating the estimates of forest height to available interferometric pairs for the entire state of Maine, thus creating a state-mosaic map of forest height. The present approach described here serves as an alternative and complementary tool for other PolInSAR inversion techniques when full-polarization data may not be available. This work is also meant to be an observational prototype for NASA's DESDynI-R (now called NISAR) and JAXA's ALOS-2 satellite missions. [ABSTRACT FROM AUTHOR]

Pulse-width modulation (PWM) inverter drive systems are widely applied in industry for their great speed-control characteristics and performance. However, the common-mode voltage of the inverter induces motor bearing voltage and bearing current, which result in premature bearing failure. In this paper, the influence of stator and rotor grounding impedances on the bearing voltage of the motor is investigated. A comprehensive bearing-current equivalent model circuit is proposed. Based on circuit analysis, the relationship between bearing voltage ratio (BVR) and grounding impedances is derived, showing that bearing voltage varies with the stator grounding impedance on a V-shaped surface. The minimum BVR appears at some specific combinations of the stator and rotor grounding impedance. Based on this, a method of suppression of rotor-grounding bearing currents based on matching the stator and rotor grounding impedances is proposed. The analytical results are verified by experimental results and show that the bearing voltage can be mitigated by matching the grounding impedances in a proper range. [ABSTRACT FROM AUTHOR]

As computational fluid dynamics (CFD) advances, entropy generation minimization based on CFD becomes attractive for optimizing complex heat-transfer systems. This optimization depends on the accuracy of CFD results, such that accurate turbulence models, such as elliptic relaxation or elliptic blending turbulence models, become important. The performance of a previously developed elliptic blending turbulence model (the SST   k – ω – φ – α model) to predict the rate of entropy generation in the fully developed turbulent circular tube flow with constant heat flux was studied to provide some guidelines for using this class of turbulence model to calculate entropy generation in complex systems. The flow and temperature fields were simulated by using a CFD package, and then the rate of entropy generation was calculated in post-processing. The analytical correlations and results of two popular turbulence models (the realizable k–ε and the shear stress transport (SST) k–ω models) were used as references to demonstrate the accuracy of the SST   k – ω – φ – α model. The findings indicate that the turbulent Prandtl number (Prt) influences the entropy generation rate due to heat-transfer irreversibility. Prt = 0.85 produces the best results for the SST   k – ω – φ – α model. For the realizable k–ε and SST k–ω models, Prt = 0.85 and Prt = 0.92 produce the best results, respectively. For the realizable k–ε and the SST k–ω models, the two methods used to predict the rate of entropy generation due to friction irreversibility produce the same results. However, for the SST   k – ω – φ – α model, the rates of entropy generation due to friction irreversibility predicted by the two methods are different. The difference at a Reynolds number of 100,000 is about 14%. The method that incorporates the effective turbulent viscosity should be used to predict the rate of entropy generation due to friction irreversibility for the SST   k – ω – φ – α model. Furthermore, when the temperature in the flow field changes dramatically, the temperature-dependent fluid properties must be considered. [ABSTRACT FROM AUTHOR]

Vehicle exhaust emissions have seriously affected air quality and human health, and understanding the emission characteristics of vehicle pollutants can promote emission reductions. In this study, a chassis dynamometer was used to study the emission characteristics of the pollutants of two gasoline vehicles (Euro 5 and Euro 6) when using six kinds of fuels. The results show that the two tested vehicles had different engine performance under the same test conditions, which led to a significant difference in their emission characteristics. The fuel consumption and pollutant emission factors of the WLTC cycle were higher than those of the NEDC. The research octane number (RON) and ethanol content of fuels have significant effects on pollutant emissions. For the Euro 5 vehicle, CO and particle number (PN) emissions decreased under the WLTC cycle, and NOx emissions decreased with increasing RONs. For the Euro 6 vehicle, CO and NOx emissions decreased and PN emissions increased with increasing RONs. Compared with traditional gasoline, ethanol gasoline (E10) led to decreases in NOx and PN emissions, and increased CO emissions for the Euro 5 vehicle, while it led to higher PN and NOx emissions and lower CO emissions for the Euro 6 vehicle. In addition, the particulate matter emitted was mainly nucleation-mode particulate matter, accounting for more than 70%. There were two peaks in the particle size distribution, which were about 18 nm and 40 nm, respectively. Finally, compared with ethanol–gasoline, gasoline vehicles with high emission standards (Euro 6) are more suitable for the use of traditional gasoline with a high RON. [ABSTRACT FROM AUTHOR]

With the continuous development of earth observation technology, space-based synthetic aperture radar (SAR) has become an important source of information for maritime surveillance, and ship classification in SAR images has also become a hot research direction in the field of maritime ship monitoring. In recent years, the remote sensing community has proposed several solutions to the problem of ship object classification in SAR images. However, it is difficult to obtain an adequate amount of labeled SAR samples for training classifiers, which limits the application of machine learning, particularly deep learning methods, in SAR image ship object classification. In contrast, as a real-time automatic tracking system for monitoring ships at sea, a ship automatic identification system (AIS) can provide a large amount of relatively easy-to-obtain labeled ship samples. Therefore, to solve the problem of SAR image ship classification and improve the classification performance of learning models with limited samples, we proposed a SAR image ship classification method based on multiple classifiers ensemble learning (MCEL) and AIS data transfer learning. The core idea of our method is to transfer the MCEL model trained on AIS data to SAR image ship classification, which mainly includes three steps: first, we use the acquired global space-based AIS data to build a dataset for ship object classification models training; then, the ensemble learning model is constructed by combining multiple base classifiers; and finally, the trained classification model is transferred to SAR images for ship type prediction. Experiments show that the proposed method achieves a classification accuracy of 85.00% for the SAR ship classification, which is better than the performance of each base classifier. This proves that AIS data transfer learning can effectively solve the problem of SAR ship classification with limited samples, and has important application value in maritime surveillance. [ABSTRACT FROM AUTHOR]

Quinone imines are important derivatives of quinones with a wide range of applications in organic synthesis and the pharmaceutical industry. The attack of nucleophilic reagents on quinone imines tends to lead to aromatization of the quinone skeleton, resulting in both the high reactivity and the unique reactivity of quinone imines. The extreme value of quinone imines in the construction of nitrogen- or oxygen-containing heterocycles has attracted widespread attention, and remarkable advances have been reported recently. This review provides an overview of the application of quinone imines in the synthesis of cyclic compounds via the domino annulation reaction. [ABSTRACT FROM AUTHOR]

E-commerce platforms incorporate reputation systems that allow buyers to rate sellers after transactions. However, existing reputation systems face challenges such as privacy leakage, linkability, and multiple rating attacks. The feedback data can inadvertently expose user information privacy because they reveal the buyers' identities and preferences, which deters a significant number of users from providing their ratings. Moreover, malicious actors can exploit data analysis and machine learning techniques to mine user privacy from the rating data, posing serious threats to user security and trust. This study introduces ARS-Chain, a pioneering and secure blockchain-driven anonymous reputation-sharing framework tailored for e-commerce platforms. The core of ARS-Chain is a dynamic ring addition mechanism with linkable ring signatures (LRS), where the number of LRS rings is dynamically added in alignment with the evolving purchase list, and LRS link tags are constructed with the LRS rings and item identifiers. Further, a consortium blockchain is introduced to store these anonymous ratings on e-commerce platforms. As a result, ARS-Chain ensures full anonymity while achieving cross-platform reputation sharing, making rating records unlinkable, and effectively countering multiple rating attacks. The experimental results confirm that ARS-Chain significantly enhances user information privacy protection while maintaining system performance, having an important impact on the construction of trust mechanisms for e-commerce platforms. [ABSTRACT FROM AUTHOR]

The myostatin (MSTN) gene also regulates the developmental balance of skeletal muscle after birth, and has long been linked to age-related muscle wasting. Many rodent studies have shown a correlation between MSTN and age-related diseases. It is unclear how MSTN and age-associated muscle loss in other animals are related. In this study, we utilized MSTN gene-edited bovine skeletal muscle cells to investigate the mechanisms relating to MSTN and muscle cell senescence. The expression of MSTN was higher in older individuals than in younger individuals. We obtained consecutively passaged senescent cells and performed senescence index assays and transcriptome sequencing. We found that senescence hallmarks and the senescence-associated secretory phenotype (SASP) were decreased in long-term-cultured myostatin inactivated (MT-KO) bovine skeletal muscle cells (bSMCs). Using cell signaling profiling, MSTN was shown to regulate the SASP, predominantly through the cycle GMP-AMP synthase-stimulator of antiviral genes (cGAS-STING) pathway. An in-depth investigation by chromatin immunoprecipitation (ChIP) analysis revealed that MSTN influenced three prime repair exonuclease 1 (TREX1) expression through the SMAD2/3 complex. The downregulation of MSTN contributed to the activation of the MSTN-SMAD2/3-TREX1 signaling axis, influencing the secretion of SASP, and consequently delaying the senescence of bSMCs. This study provided valuable new insight into the role of MSTN in cell senescence in large animals. [ABSTRACT FROM AUTHOR]