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Abstract Low temperature is one of the environmental factors that restrict the growth and geographical distribution of Brassica. To investigate the effects of exogenous calcium and calcium inhibitor on the ability of winter turnip rapeseed (Brassica rapa L.) to withstand low temperatures (4℃), we used a strong cold-resistant variety Longyou 7 (L7) and a weak cold-resistant variety Longyou 99 (L99) as the materials. The seedlings were treated with CaCl2 (20 mmol·L-1) and calcium inhibitor LaCl3 (10 mmol·L-1) at 0 h (CK), 6 h, 12 h, 24 h and 48 h after 4℃ treatments. Physiological characteristics, Ca2+ flux and Ca2+ concentration in roots after treatments were analyzed. Results illustrated that under 4℃ treatment, activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) increased by both CK and exogenous CaCl2 treatments. Contents of soluble protein (SP) and proline (Pro) increased, while contents of malondialdehyde (MDA) decreased, resulting in reduced membrane lipid peroxidation. But enzyme activity decreased and MDA content increased following treatment with exogenous LaCl3. The rate of Ca2+ flow showed a higher uptake in L7 roots compared with L99. L99 showed Ca2+ efflux with a rate of 30.21 pmol‧cm-2‧s-1, whereas L7 showed short efflux then returned to influx. Calcium ion content in roots decreased in both cultivars after CaCl2 treatment. Results of RNA-seq revealed that genes were differentially expressed in response to low temperatures, hormones, photosystem II, chloroplasts, DNA replication, ribosomal RNA processing, and translation. This study found significant expression genes related to cellular signal transduction (MAPK signaling pathway) and material metabolism (nitrogen metabolism, glycerol ester metabolism).It was also analyzed by WGCNA that two modules had the strongest correlation with physiological indicators. Eight candidate genes were identified among MAPK signaling pathway and the two modules.

Cervical spondylotic myelopathy (CSM) is the most serious subtype of cervical spondylosis, which is the main cause of spinal cord dysfunction in middle-aged and elderly people, and the pathogenesis of this CSM is complex, mainly including degenerative aging, dynamic instability, spinal cord ischemia, spinal cord injury, inflammation, apoptosis, and other possible mechanisms. The clinical treatment of the CSM mainly includes conservative treatment and surgical treatment, conservative treatment includes drugs, acupuncture, moxibustion, traction, physical therapy and manual treatment, surgical treatment can be divided into anterior surgery, posterior surgery, anterior and posterior combined surgery according to the surgical approach. The choice of treatment regimen should be based on the patient's symptoms, signs, and the results of auxiliary examinations, but how to choose the appropriate treatment plan is still the focus of clinicians. This article focuses on the research progress of the pathogenesis and treatment methods of this disease, in order to provide a reference for the diagnosis and treatment of cervical myelopathy.

[ Objective ] The NAC transcription factor family is a class of transcription factors that is widely studied in plants. It plays an important role in regulating plant growth and development and responding to abiotic stress. Maize is one of the three major food crops , which faces various adverse stresses in growth and development. Salt stress is one of the main environmental factors limiting crop growth and produc- tion. Therefore , it is of great significance to identify maize salt resistance genes and analyze their salt re- sistance mechanism for breeding stress-resistant maize varieties. [ Methods ] This study cloned the maize transcription factor ZmNAC59 and analyzed its conserved domain and phylogenetic relationship using bioinformatics methods. The expression pattern of the gene in leaves under NaCl and MeJA treatments was analyzed using the quantitative real-time PCR method. The stable transgenic system was used to het- erologously express the gene in Arabidopsis thaliana for phenotype observation. At the same time , virus- induced silencing technology was used to silence the gene in maize , followed by phenotype observation un- der salt stress and enzyme activity detection. [ Results ] The qRT-PCR results showed that ZmNAC59 was up-regulated by NaCl and MeJA treatments. After virus-induced silencing of ZmNAC59 , the silenced strains were more sensitive to salt stress and accumulated more ROS. After over expression of ZmNAC59 in A . thaliana , the over expression lines had higher survival rate , less accumulation of ROS , and lower Na + / K + ratios under salt stress , indicating that ZmNAC59 , as a positive regulator of salt stress , can im- prove plant salt resistance by regulating ion homeostasis. qRT-PCR results showed that Na + and K + transport related genes were significantly up-regulated in A . thaliana overexpression lines. After transient expression of ZmNAC59 in maize protoplasts , the expression of ZmSOS1 , ZmNHX1 , and ZmNHX7 were significantly up-regulated after salt treatment. The Dual-LUC experiment showed that ZmSOS1 was the target gene of ZmNAC59. [ Conclusion ] This study finds that ZmNAC59 activates ZmSOS1 promoter and regulates its expression to promote ion transport under salt stress , thereby improving plant salt resist- ance. This provides a basis for the screening of maize stress resistant genes and variety cultivation.

Due to climate change, extreme heat stress events have become more frequent, adversely affecting rice yield and grain quality. The accumulation and translocation of dry matter and nitrogen substances are essential for rice yield and grain quality. To assess the impact of high temperature stress (HTS) at the early panicle initiation (EPI) stage on the accumulation, transportation, and distribution of dry matter and nitrogen substances in various organs of rice, as well as the resulting effects on rice yield and grain quality, pot experiments were conducted using an indica rice cultivar Yangdao 6 (YD6) and a japonica rice cultivar Jinxiangyu 1 (JXY1) under both normal temperature (32 ºC / 26 ºC) and high temperature (38 ºC / 29 ºC) conditions. The results indicated that exposure to HTS at the EPI stage significantly decreased rice yield by reducing spikelet number per panicle, grain-filling rate, and grain weight. However, it improved the nutritional quality of rice grains by increasing protein and amylose contents. The reduction in nitrogen and dry matter accumulation accounted for the changes in spikelet number per panicle, grain-filling rate, and grain size. Under HTS, the decrease in nitrogen accumulation accompanied by the reduction in dry matter may be due to the down-regulation of leaf net photosynthesis and senescence, as evidenced by the decrease in nitrogen content. Furthermore, the decrease in sink size limited the translocation of dry matter and nitrogen substances to grains, which was closely related to the reduction in grain weight and the deterioration of grain quality. These findings significantly contribute to our understanding of the mechanisms of HTS on grain yield and quality formation from the perspective of dry matter and nitrogen accumulation and translocation. Further efforts are needed to improve the adaptability of rice varieties to climate change in the near future.

This paper explores the application of network security technology within intelligent information terminals of the Internet of Things (IoT). It examines existing security issues and proposes a technical framework to address them. The technical framework starts from two aspects of data encryption and intrusion detection technology, in the data encryption technology, the CCA-ANC encryption algorithm is proposed to change the attacker in ANC from pure ciphertext attack to using the method of selective ciphertext attack. In intrusion detection technology, the DAGMM algorithm has been improved and optimized. The WEFS-DAGMM improved intrusion detection algorithm has been proposed, and an intrusion detection firewall has been constructed. In the performance test, the CCA-ANC encryption algorithm completes the encryption after inputting 1024MB of data in 13.6s, and the average speed of encryption reaches 71.54MB/s. The optimized WEFS-DAGMM algorithm achieves an accuracy of 0.952, which is 0.03 higher than the original DAGMM algorithm. The recall and F1 values are 0.03 higher than the original DAGMM algorithm, respectively. The algorithms have been improved by 0.03 and 0.037, respectively. Simulation experiments are conducted on the technical framework constructed in this paper. The success rate of malicious attack detection is greater than 90%, and the security protection rate reaches more than 99% in all of them.

In this study, the effects of Mg addition on the organization refinement and mechanical properties of the alloys were investigated by designing Zn-Mg binary alloys with different compositions. Solution treatment and cold drawing successfully prepared fine wire materials with smooth surface and uniform organization. The material’s mechanical properties were further improved by treating the fine wires with an optimized annealing process. Electrochemical tests and in vitro degradation experiments showed that the degradation properties of the alloy in simulated body fluids were closely related to the alloy composition and microstructure. Cytotoxicity tests showed that the prepared Zn-Mg alloys were significantly cytotoxic to tumor cells. The corrosion weight loss analysis revealed the corrosion behavior of the alloy and its trend with time. Overall, this study provides critical experimental data and theoretical basis for preparing biodegradable biomedical metal-zinc alloys with excellent performance, and lays a solid foundation for future clinical applications.

As the growth of automated detection technology, traditional manual detection has gradually been replaced. To improve the effectiveness of defect detection, a HPLC/dual mode portable sorting device with deep learning and image processing is raised for apparent defect detection. The product image is segmented using flood filled mean shift method, and defect detection is achieved using Yolo v3 algorithm. An LME2918 chip is the main component of the communication module in the portable device. Based on experimental data, image segmentation accuracy can range from 80% to 100%, and image matching accuracy can range from 85% to 95%. Under the power line carrier mode, the average success rate of apparent defect detection in portable sorting devices can reach 85%, and the change in success rate is not significant, indicating that the detection is relatively stable; Under wireless communication mode, the average success rate can reach 83%, and the change in success rate is relatively obvious, because wireless communication is easily affected by the external environment. The experimental data shows that the defect detection effect of the HPLC/dual mode portable sorting device based on deep learning and image processing meets the design requirements.

In order to evaluate the dependability and validity of the scale, this paper first examines the features of farming direct seeding. It then builds a scale that includes charm, expertise, interactivity, spatial presence, perceived value, platform notoriety, and buy intention. The project’s internal coherence and logic are confirmed by extracting the common factors using the principal component analysis method, followed by factor rotation using the maximum variance method. In order to confirm the relationship between anchor characteristics, spatial presence, perceived value, platform reputation, and purchase intention, we conduct an empirical study on the impact of live-streaming media characteristics on consumers’ purchase intentions. We also conduct correlation analysis, regression analysis, adjustment effect test, and hypothesis test. Interactivity has a considerable positive impact on perceived value, as evidenced by the magnitude of the standardized regression coefficient of 0.138 and Sig=0.019005. Professionalism has a strong positive impact on perceived value, as shown by the standardized regression coefficient of professionalism on perceived value, which is 0.292, Sig=0.0000.05. Living agricultural products must combine their own qualities and concentrate on the marketing and selling their wares.

The northern South China Sea continental margin is the key or critical segment of the Ocean-Continent Connection Zone (OCCZ) of the Great South China Block, the junction between the Tethyan and the (Paleo-) Pacific dynamic systems, and the interaction area between the Indian Ocean and the Pacific Ocean. However, due to the low-degree geophysical exploration in the past, the regional tectonic background, processes and mechanism of the transition between the Tethyan and the Pacific tectonic domains are unclear. Based on the latest large number of seismic profiles, we focus on the Cenozoic basin structure in the continental margin of the northern South China Sea and try to reveal the Mesozoic basement structures of the northern South China Sea continental margin, with the aim of exploring the pre-Cenozoic tectonic evolution and the Cenozoic opening, spreading, ridge fossil and closure of the South China Sea oceanic basin, so as to serve the accurate oil and gas exploration in this area at the same time. The seismic interpretation of the Pearl River Mouth Basin and the field structural investigation of the South China continental margin show that the OCCZ of the South China Block has experienced three processes: Mesozoic Indosinian collisional orogeny, Early Yanshanian accretionary orogeny and Late Yanshanian transpressive orogeny. During the Cenozoic era, it experienced the dispersive extension into basins under the control of NW-SE-directed normal extension in the early stage, the dextral pull-apart into basins under the control of NE-NNE-trending strike-slip faults in the middle stage, and the sinistral pull-apart into basins under the control of NW-WNW strike-slip faults in the late stage. In general, the transition process from the Tethyan to the Pacific tectonic systems can be subdivided into four stages: the transition from the Paleo-Tethyan to the Neo-Tethyan tectonic systems, the transition from the Neo-Tethyan to the Paleo-Pacific tectonic systems, the transition from the Neo-Tethyan to the Pacific tectonic systems, and the transition from the Paleo-Pacific to the Pacific tectonic systems. The tectonic transition of the East Asian OCCZ reflects the long-term mechanism of the Earth plate dynamic system driving the plate superconvergence in East Asia, in particular of the importance of the deep or submarine “Triple Poles”, the Southeast Asian U-shape subduction system, the Pacific LLSVP and the African LLSVP. More importantly, the Southeast Asian U-shape subduction system is also one of the important dynamic engines of the Earth plate motion.

Objective To study the role of DNA methylation in oral leukoplakia carcinogenesis. Methods DNA methylation was detected in forty cases of oral squamous cell carcinoma (OSCC), twenty-eight cases of oral leukoplakia (OLK) and forty cases of healthy oral mucosa. Download the expression profile data of OSCC, OLK and healthy oral mucosa from Gene Expression Omnibus (GEO) database. DNA methylation data and expression profile data were compared for repeatability, DNA methylation data for difference analysis and corresponding expression profile data for IPA pathway analysis. Results The data analysis showed that DNA methylation had greater flexibility and instability. Ingenuity Pathway Analysis (IPA) analysis showed that genes related to OLK differential methylation sites were mainly concentrated in the process of cell movement and differentiation. Genes related to differential methylation sites of OSCC are mainly enriched in cell proliferation, migration, oxidation regulation, and anti-apoptosis processes. The genes associated with OLK and OSCC differential methylation sites are co-enriched in phosphoinositol metabolism and phospholipase C signaling pathway. Conclusion DNA methylation is involved in the formation of oral squamous cell carcinoma, and the activation of phosphoinositol metabolism may promote oral leukinoma.

Kinase-targeted cancer therapy (KTCT) with ATP-competitive inhibitors has been widely applied in clinics. However, a number of kinase missense mutations were observed to confer acquired drug resistance during therapy, largely limiting the clinical application of kinase inhibitors in KTCT. Instead of directly influencing inhibitor binding, kinase mutations can also cause generic resistance to ATP-competitive inhibitors by increasing ATP affinity. Herein, the intermolecular interaction of the ATP molecule with clinically observed drug-resistant EGFR family kinase mutations involved in human cancer are systematically characterize. Rigorous quantum mechanics/molecular mechanics (QM/MM) calculation and empirical Poisson–Boltzmann/surface area (PB/SA) analysis as well as in vitro kinase assay and surface plasmon resonance analysis were integrated to explore the binding capability of ATP to mutant residues in the structural context of the kinase domain, which resulted in a comprehensive profile of ATP response to acquired drug-resistant mutations of four EGFR family kinases (EGFR/ErbB1, ErbB2, ErbB3 and ErbB4). From the profile, it was possible to identify those potent mutations that may influence ATP binding significantly; such mutations are potential candidates to cause generic resistance for ATP-competitive inhibitors. Consequently, the well documented generic drug-resistant mutation EGFR T790M and its counterpart ErbB2 T798M are found to increase ATP affinity by establishing an additional S–π interaction between the side-chain thioether group of the mutant Met residue and the aromatic adenine moiety of the ATP molecule, while EGFR D761Y is identified as a new generic drug-resistant mutation that can increase ATP affinity by eliminating unfavorable electrostatic repulsion. In contrast, ErbB2 K753E and T768I are considered to be two generic drug-sensitive mutations that can decrease ATP affinity by unfavorable charge reversal and by impairing favorable polar interaction, respectively. In addition, the EGFR L858R mutation is located at the kinase activation loop and nearby the kinase active site, thus largely complicating the multiply dependent relationship of kinase, ATP and inhibitor, which therefore exhibits divergent effects on different tested inhibitors.

The high temperature requirement A (HtrA) protease plays a crucial role in protein quality control and cell fate. The enzyme contains a catalytic protease domain and a regulatory PDZ domain; the latter determines the substrate specificity of the former by specifically binding to the C-terminal hydrophobic stretch of its partner proteins. Previously, a pentapeptide ligand H3C1 was identified as the potential binder of HtrA PDZ domain using phage display technique. Here, an orthogonal π–cation–π stacking system at the crystal domain–peptide complex interface was analysed by integrating theoretical calculations and experimental assays. It was demonstrated that there is a strong (positive) synergistic effect between the two wings of the stacking system; breaking of cation–π interaction in one wing can largely impair the interaction strength of another wing. The π-electron contributes primarily to the synergistic effect, although geometric property is also (marginally) responsible for it. Next, the systematic combinations between the four aromatic amino acids (Phe, Tyr, Trp and His) plus one non-aromatic amino acid (Ala) at the two wings of π–cation–π stacking were investigated. It was found that two aromatic substitutions (Phe-4Tyr and Phe-4Trp) at a wing can considerably and moderately improve peptide affinity by 3.2- and 1.5-fold, respectively, whereas the non-aromatic mutations at each wing and at both of them can significantly reduce the affinity with Kd increase from 1.8 (wild type) to 34 μM and 160 μM (single-point mutations), as well as 210 μM (double-point mutation), suggesting that just breaking of one wing can substantially undermine the synergism of orthogonal π–cation–π stacking.

For sluices built on soil foundations, seepage safety of the foundation is one of the most concerns during operation of sluices. Monitoring data could reflect the real seepage behavior in the foundation, but of which the shortcoming is that generally only the local seepage states can be measured. The seepage field in the whole foundation can be analyzed by numerical simulation. The permeability coefficients of the foundation materials significantly affect the numerical simulation results; however, it is difficult to accurately determine the values of permeability coefficients. In this paper, an approach based on response surface method (RSM) for calibration of permeability coefficients was proposed, and the efficiency of parameter calibration is improved by constructing the response surface equation instead of time-consuming finite element calculation of foundation seepage. The seepage in a sluice foundation was analyzed using monitoring data and numerical simulation. The monitoring data showed that the seepage pressure in the foundation periodically varies with high value in flood season and low value in dry season. After calibration of the permeability coefficients of the foundation materials using the measured seepage pressure, the seepage fields in the foundation for different water levels were numerically simulated to investigate the cause for the periodical variation of the seepage pressure and the seepage safety of the foundation was assessed with the calculated seepage gradients. The methods adopted in this study could be applied to seepage analysis for sluice foundations with similar geologic conditions and antiseepage measures.