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In the southeast coast of China, typhoon rainstorms resulted in lots of landslides. Investigating rainfall thresholds and patterns of typhoons is of great importance for the early warning of landslides. In this study, the landslide information obtained from multiple sources and typhoon rainstorm data were used to analyze landslide and rainfall characteristics in Taishun 2007 to 2022; the rainfall threshold of typhoon rainstorm-induce landslides was defined for Taishun area based on the rainfall intensity–duration (I-D) model. It finds that a large number of typhoon rainstorm landslides occur at the windward slope close to the landing direction of the typhoon, where the main vegetation types of the landslide are arbors and herbs with tall trunks and shallow roots. The duration of rainfall events inducing landslides is usually 2～3 days, with concentrated rainfall and total rainfall more than 200 mm. The threshold of typhoon rainstorm-induced landslides is significantly higher than that of rainfall-induced landslides in other regions. With the backward position of rainfall peak in rainfall process, the thresholds become lower and steeper, indicating that more rainfall is needed to trigger landslides when the rainfall peak appears earlier than when it is late. Typhoon rainstorm-induced landslides are more sensitive to the heavy rainfall event after a long rainfall. The threshold model established in this study is consistent with the observation, indicating that it is effective for landslide monitoring during the typhoon season.

FLOWERING LOCUS T (FT) are well-known key genes for initiating flowering in plants. Delineating the evolutionary history and functional diversity of FT genes is important for understanding the diversification of flowering time and how plants adapt to the changing surroundings. We performed a comprehensive phylogenetic analysis of FT genes in 47 sequenced flowering plants and the 1,000 Plant Transcriptomes (1KP) database with a focus on monocots, especially cereals. We revealed the evolutionary history of FT genes. The FT genes in monocots can be divided into three clades (I, II, and III), whereas only one monophyletic group was detected in early angiosperms, magnoliids, and eudicots. Multiple rounds of whole-genome duplications (WGD) events followed by gene retention contributed to the expansion and variation of FT genes in monocots. Amino acid sites in the clade II and III genes were preferentially under high positive selection, and some sites located in vital domain regions are known to change functions when mutated. Clade II and clade III genes exhibited high variability in important regions and functional divergence compared with clade I genes; thus, clade I is more conserved than clade II and III. Genes in clade I displayed higher expression levels in studied organs and tissues than the clade II and III genes. The co-expression modules showed that some of the FT genes might have experienced neofunctionalization and subfunctionalization, such as the acquisition of environmental resistance. Overall, FT genes in monocots might form three clades by the ancient gene duplication, and each clade was subsequently subjected to different selection pressures and amino acid substitutions, which eventually led to different expression patterns and functional diversification. Our study provides a global picture of FT genes’ evolution in monocots, paving a road for investigating FT genes’ function in future.

Abstract Background Crassulacean acid metabolism (CAM) photosynthesis is an important carbon fixation pathway especially in arid environments because it leads to higher water-use efficiency compared to C3 and C4 plants. However, the role of DNA methylation in regulation CAM photosynthesis is not fully understood. Results Here, we performed temporal DNA methylome and transcriptome analysis of non-photosynthetic (white base) and photosynthetic (green tip) tissues of pineapple leaf. The DNA methylation patterns and levels in these two tissues were generally similar for the CG and CHG cytosine sequence contexts. However, CHH methylation was reduced in white base leaf tissue compared with green tip tissue across diel time course in both gene and transposon regions. We identified thousands of local differentially methylated regions (DMRs) between green tip and white base at different diel periods. We also showed that thousands of genes that overlapped with DMRs were differentially expressed between white base and green tip leaf tissue across diel time course, including several important CAM pathway-related genes, such as beta-CA, PEPC, PPCK, and MDH. Conclusions Together, these detailed DNA methylome and transcriptome maps provide insight into DNA methylation changes and enhance our understanding of the relationships between DNA methylation and CAM photosynthesis.

Abstract Unlike the flower of the model monocot rice, which has diverged greatly from the ancestral monocot flower, the pineapple (Ananas comosus) flower is more typical of monocot flowers. Here, we identified 43 pineapple genes containing MADS-box domains, including 11 type I and 32 type II genes. RNA-seq expression data generated from five pineapple floral organs (sepals, petals, stamens, pistils, and ovules) and quantitative real-time PCR revealed tissue-specific expression patterns for some genes. We found that AcAGL6 and AcFUL1 were mainly expressed in sepals and petals, suggesting their involvement in the regulation of these floral organs. A pineapple ‘ABCDE’ model was proposed based on the phylogenetic analysis and expression patterns of MADS-box genes. Unlike rice and orchid with frequent species-specific gene duplication and subsequent expression divergence, the composition and expression of the ABCDE genes were conserved in pineapple. We also found that AcSEP1/3, AcAG, AcAGL11a/b/c, and AcFUL1 were highly expressed at different stages of fruit development and have similar expression profiles, implicating these genes’ role in fruit development and ripening processes. We propose that the pineapple flower can be used as a model for studying the ancestral form of monocot flowers to investigate their development and evolutionary history.

We are now witnessing a dramatic growth of heterogeneous data, consisting of a complex set of cross-media content, such as texts, images, videos, audio, graphics, spatio-temporal data, and multivariate time series. The inception of modern techniques from computer science have offered very robust and hi-tech solutions for data and information analysis, collection, storage, and organization, as well as product and service delivery to customers. Recently, technological advancements, particularly in the form of big data, have resulted in the storage of enormous amounts of potentially valuable data in a wide variety of formats. This situation is creating new challenges for the development of effective algorithms and frameworks to meet the strong requirements of big data representation and analysis, knowledge understanding, and discovery.

The R2R3-MYB transcription factors play critical roles in various processes in embryophytes (land plants). Here, we identified genes encoding R2R3-MYB proteins from rhodophytes, glaucophytes, Chromista, chlorophytes, charophytes, and embryophytes. We classified the R2R3-MYB genes into three subgroups (I, II, and III) based on their evolutionary history and gene structure. The subgroup I is the most ancient group that includes members from all plant lineages. The subgroup II was formed before the divergence of charophytes and embryophytes. The subgroup III genes form a monophyletic group and only comprise members from land plants with conserved exon–intron structure. Each subgroup was further divided into multiple clades. The subgroup I can be divided into I-A, I-B, I-C, and I-D. The I-A, I-B, and I-C are the most basal clades that have originated before the divergence of Archaeplastida. The I-D with the II and III subgroups form a monophyletic group, containing only green plants. The II and III subgroups form another monophyletic group with Streptophyta only. Once on land, the subgroup III genes have experienced two rounds of major expansions. The first round occurred before the origin of land plants, and the second round occurred after the divergence of land plants. Due to significant gene expansion, the subgroup III genes have become the predominant group of R2R3-MYBs in land plants. The highly unbalanced pattern of birth and death evolution of R2R3-MYB genes indicates their important roles in the successful adaptation and massive radiation of land plants to occupy a multitude of terrestrial environments.

Abstract In this paper, by a constructive proof based on the homotopy continuation method, we prove that the second order system x″=g(t,x) $x''=g(t,x)$ admits rotating periodic solutions with form u(t+T)=Qu(t) $u(t+T)=Qu(t)$ for any orthogonal matrix Q when the nonlinearity g admits the Hartman-type condition.

Implementing telemedicine solutions has recently become a trend among various research teams at an international level. Telemedicine refers to the use of modern information and communication technologies to meet the needs of citizens, patients, healthcare professionals, and healthcare providers, as well as policy makers. Telemedicine applications are very promising and have great potential; they can play a very important role in service provision by improving access, equity and quality through connecting healthcare facilities and healthcare professionals, and diminishing geographical and physical barriers. However, the transmission and access technologies of medical information raise critical issues that urgently need to be addressed, especially those related to security. Further, medical identity theft is a growing and dangerous crime. Stolen personal information can have a negative financial impact, but stolen medical information cuts to the very core of personal privacy. Medical identity theft already costs billions of dollars each year, and altered medical information can put a person’s health at risk through misdiagnosis, delayed treatment or incorrect prescriptions. Yet, the use of hand devices to store, access, and transmit medical information is outpacing the privacy and security protection on those devices. Therefore, the authenticity of the information and related medical images is of prime concern as they form the basis of inference for diagnostic purposes. In such applications, tamper proofing and guaranteed originality of medical data/information is achieved by embedding some kind of watermark(s) which must be secure and robust against malicious attacks. Robustness and security of medical data/information against attacks is an interesting, challenging area for researchers. Potential researchers are using watermarking and cryptography to disseminate security to the medical data. Further, noted researchers are using watermarking techniques in the field of healthcare to address health data management issues, including source and data authentication, efficient image archiving and retrieval, optimizing bandwidth required to transmit the data, and highlighting diagnostically significant regions.

Abstract Background Drought stress is one of the major natural challenges in the main tea-producing regions of China. The tea plant (Camellia sinensis) is a traditional beverage plant whose growth status directly affects tea quality. Recent studies have revealed that microRNAs (miRNAs) play key functions in plant growth and development. Although some miRNAs have been identified in C. sinensis, little is known about their roles in the drought stress response of tea plants. Results Physiological characterization of Camellia sinensis ‘Tieguanyin’ under drought stress showed that the malondialdehyde concentration and electrical conductivity of leaves of drought-stressed plants increased when the chlorophyll concentration decreased under severe drought stress. We sequenced four small-RNA (sRNA) libraries constructed from leaves of plants subjected to four different treatments, normal water supply (CK); mild drought stress (T1); moderate drought stress (T2) and severe drought stress (T3). A total of 299 known mature miRNA sequences and 46 novel miRNAs were identified. Gene Ontology enrichment analysis revealed that most of the differentially expressed-miRNA target genes were related to regulation of transcription. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the most highly enriched pathways under drought stress were D-alanine metabolism, sulfur metabolism, and mineral absorption pathways. Real-time quantitative PCR (qPCR) was used to validate the expression patterns of 21 miRNAs (2 up-regulated and 19 down-regulated under drought stress). The observed co-regulation of the miR166 family and their targets ATHB-14-like and ATHB-15-like indicate the presence of negative feedback regulation in miRNA pathways. Conclusions Analyses of drought-responsive miRNAs in tea plants showed that most of differentially expressed-miRNA target genes were related to regulation of transcription. The results of study revealed that the expressions of phase-specific miRNAs vary with morphological, physiological, and biochemical changes. These findings will be useful for research on drought resistance and provide insights into the mechanisms of drought adaptation and resistance in C. sinensis.