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Abstract [Objective] The Northern Hengduan Mountains are rich in biodiversity. Over the last 10 years, there have been many reports of the biodiversity of the region. The team conducted a survey of plant diversity and vegetation structure in Northern Hengduan Mountains from June to August 2023. [Methods] Through field investigation and collection and photograph of plants, as well as preparing, classifying, and identifying specimens. [Results] Eight newly recorded species were reported from Chaya of Changdu in the Northern Hengduan Mountains in Xizang. They were Ephedra minuta Florin (Ephedraceae), Caragana korshinskii Kom. (Fabaceae), Rhododendron luhuoense H. P. Yang (Ericaceae), R. orthocladum var. longistylum Philipson et M. N. Philipson (Ericaceae), R. thymifolium Maxim. (Ericaceae), R. nivale Hook. f. subsp. australe Philipson et M. N. Philipson (Ericaceae), Artemisia capillaris Thunb. (Asteraceae), and Chenopodiastrum gracilispicum (H.W.Kung) Uotila (Amaranthaceae) [Conclusion] The discovery of the newly distributed plants is an important supplement for the flora of the Hengduan Mountains in Xizang. The voucher specimens are stored in the herbarium of Yibin University

The application of bio-based solvents for living radical polymerization has been a hot topic in recent year. In this article, γ-valerolactone (GVL), a bio-based solvent as green media for ARGET atom transfer radical polymerization (ATRP) of styrene (St) were investigated. We first conducted polymerization of St in γ-valerolactone using copper(ii) bromide as the catalyst, tris(2-pyridylmethyl) amine as the ligand, and only sodium ascorbate as reducing agent. The polymerization achieved moderate conversion; however, the controllability of polymerization was not very good, providing a polymer with a broad molecular weight distribution (M w/M n > 1.30). When sodium carbonate is introduced, excellent results were obtained providing high yields and low M w/M n values under very low catalyst usage (∼5 ppm). 1H NMR spectroscopy, chain extension, and MALDI–MS experiments confirmed the final polymer chains with high fidelity. The use of GVL solvent opens a new route for the easy synthesis of PS through ARGET ATRP with low catalyst usage conditions.

With the development of clinical informatization technology, a large amount of data resources has been accumulated in the medical field, among which Athletes’ electronic medical records (EMRs) are one of the important data sources of clinical informatization and contain rich medical knowledge, how to obtain valuable biometric features from these data has become the basis of medical intelligence research. Therefore, this paper takes structured text as the entry point, and firstly, the research status of information extraction is elaborated. Moreover, in the work of e-medical biometrics recognition, medical text is added to the language model BERT for pre-training and fine-tuning, and a multi-head self-attention mechanism is introduced to incorporate a bidirectional LSTM model for feature extraction, and biometric features are extracted by using a stochastic conditional field as a classification constraint. This design bypasses the character-level image segmentation step for text line images, thus avoiding the overall accuracy degradation caused by the backward accumulation of errors in character segmentation. Finally, the experimental results show that the model can effectively accomplish the related biological feature extraction tasks. [ABSTRACT FROM AUTHOR]

[Objective] As a typical structure of carbonate rocks, the formation of stylolites is of great significance for the enrichment of organic matter and fluid migration within the carbonate rock itself. However, there is currently no in-depth research on the source of organic matter and the mechanism of fluid transport in stylolites. [Methods] This study collected carbonate core samples containing stylolites from the Dachigan structural belt in the eastern Sichuan Basin. The stylolites and matrix were respectively subjected to organic carbon and pyrolysis (Rock-Eval), common thin section observation, thin section observation under fluorescent light, whole rock X-ray diffraction, carbon and oxygen isotopes and scanning electron microscopy (SEM) and other testing items. [Results and Conclusions] The organic matter occurred in the stylolites is mainly in the form of three types including soluble organic matter, pyrobitumen, and bitumen, indicating that the organic matter in the stylolites is mainly the secondary migrated organic matter. Secondary dolomite and pyrite are well developed in the stylolites that the intercrystalline pore spaces and fractures are retained, thereby to provide good conditions for the accumulation and migration of oil and gas. The strong cementation on the contact between the stylolites and matrix and the formation of secondary minerals nearby may be the results of fractionation when the hydrocarbon fluid migrates from the matrix to stylolites. Through analysis, it is believed that the strong cementation at the contact interface between the suture and the matrix, as well as the formation of nearby secondary minerals, are the reasons for the fractionation effect of hydrocarbon fluids when migrating from the matrix to the suture. Through this study, it was found that during the development of sutures, the organic matter in the sutures will crack and form natural gas during the high evolution stage. When mixed with natural gas of other origins, it will affect the identification of natural gas sources ; When the suture line serves as a migration channel for crude oil, the fractionation effect on crude oil can also cause certain difficulties in identifying the source of crude oil. Therefore, appropriate biomarker comparison parameters should be selected to analyze the oil source relationship, and the spatial variation pattern of crude oil properties should also be considered. [ABSTRACT FROM AUTHOR]

With increasing demand for scratch-resistant flexible electronics, the development of transparent coatings with good scratch resistance and self-healing properties has emerged as a key research topic. In this study, a high-strength self-healing poly(urethane – urea) (PUU)-based nanocomposite coating was prepared by introducing functionalized nanodiamond (ND) into a PUU matrix via solution blending. The PUU matrix had hard-segment repeating units and was constructed using isophorone diamine and isophorone isocyanate. The ND particles were modified using a silane coupling agent, 3-aminopropyltriethoxysilane, to obtain well-dispersed KH-ND nanoparticles. KH-ND promoted microphase separation in the PU matrix, inducing the formation of dense and homogeneous hard domains that dissipated stress, prevented further crack development, and improved the mechanical properties and scratch resistance of the coating. In addition, the coating exhibited excellent self-healing properties. Fourier-transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy were used to characterize the self-healing and hardening mechanisms of the coating. The environmentally friendly PUU/KH-ND coating is easy to prepare and has broad application prospects in transparent and anti-scratch coatings for flexible electronics, automobiles, and home appliances. [ABSTRACT FROM AUTHOR]

Waterlogging stress is a severe abiotic challenge that impedes plant growth and development. Ramie (Boehmeria nivea L.) is a Chinese traditional characteristic economic crop, valued for its fibers and by-products. To investigate the waterlogging tolerance of ramie and provide the scientific basis for selecting waterlogging-tolerant ramie varieties, this study examined the morphological, physiological, biochemical, and molecular responses of 15 ramie germplasms (varieties) under waterlogging stress. The results revealed varied impacts of waterlogging stress across the 15 ramie varieties, characterized by a decrease in SPAD values, net photosynthesis rates, and relative water content of ramie leaves, along with a significant increase in relative conductivity and the activities of antioxidant enzymes such as SOD, POD, CAT, and APX. Additionally, the levels of soluble sugars, soluble proteins, and free proline exhibited varying degrees of increase. Through Principal Component Analysis (PCA), ZZ_2 and ZSZ_1 were identified as relatively tolerant and susceptible varieties. Transcriptome analysis showed that the differential expressed genes between ZZ_2 and ZSZ_1 were significantly enriched in metabolic pathways, ascorbate and aldarate metabolism, and inositol phosphate metabolism, under waterlogging stress. In addition, the expression of hypoxia-responsive genes was higher in ZZ_2 than in ZSZ_1 under waterlogging stress. These differences might account for the varied waterlogging responses between the two varieties. Therefore, this study explored the morpho-physiological responses of ramie under waterlogging stress and identified the molecular mechanisms involved, providing valuable insights for improving ramie varieties and breeding new ones., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Background: Protein phosphatase class 2 C (PP2C) is the largest protein phosphatase family in plants. Members of the PP2C gene family are involved in a variety of physiological pathways in plants, including the abscisic acid signalling pathway, the regulation of plant growth and development, etc., and are capable of responding to a wide range of biotic and abiotic stresses, and play an important role in plant growth, development, and response to stress. Apocynum is a perennial persistent herb, divided into Apocynum venetum and Apocynum hendersonii. It mainly grows in saline soil, deserts and other harsh environments, and is widely used in saline soil improvement, ecological restoration, textiles and medicine. A. hendersonii was found to be more tolerant to adverse conditions. The main purpose of this study was to investigate the PP2C gene family and its expression pattern under salt stress and to identify important candidate genes related to salt tolerance., Results: In this study, 68 AvPP2C genes and 68 AhPP2C genes were identified from the genomes of A. venetum and A. hendersonii, respectively. They were classified into 13 subgroups based on their phylogenetic relationships and were further analyzed for their subcellular locations, gene structures, conserved structural domains, and cis-acting elements. The results of qRT-PCR analyses of seven AvPP2C genes and seven AhPP2C genes proved that they differed significantly in gene expression under salt stress. It has been observed that the PP2C genes in A. venetum and A. hendersonii exhibit different expression patterns. Specifically, AvPP2C2, 6, 24, 27, 41 and AhPP2C2, 6, 24, 27, 42 have shown significant differences in expression under salt stress. This indicates that these genes may play a crucial role in the salt tolerance mechanism of A. venetum and A. hendersonii., Conclusions: In this study, we conducted a genome-wide analysis of the AvPP2C and AhPP2C gene families in Apocynum, which provided a reference for further understanding the functional characteristics of these genes., (© 2024. The Author(s).)

CuI films present promising optoelectronic properties for transparent conductors. However, the high hole concentration in CuI films hinders the controllable modulation of hole mobility, limiting their application in low-dimensional thin-film transistors. In this study, CuI films were prepared through a Cu film iodination method at room temperature, and a systematic investigation was conducted on the modulation of hole concentration and mobility with varying film thickness. The films exhibited a zinc blende structure (γ-phase) with increasing grain size as the thickness increased. The transmittance and optical bandgap of the films decreased with increasing thickness. The correlation of vacancy concentration with changing film thickness was analyzed through photoluminescence spectroscopy, revealing the influence of grain boundary migration on vacancy formation. The reduction in film thickness diminishes the migration of CuI grain boundaries, consequently reducing the probability of Cu vacancy and I vacancy formation, resulting in diminished hole concentration and enhanced hole mobility and film conductivity. The film with a thickness of 20 nm demonstrated optimal performance, with a transmittance of 90%, hole concentration of 4.09 × 10 17 cm -3 , hole mobility of 506.50 cm 2 V -1 s -1 , and conductivity of 33.19 S cm -1 . This work deepens the understanding of hole transport such as hole concentration and mobility modulation in CuI films, highlighting the importance of controlling grain boundary migration during the film growth process., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)