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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]

Purpose: The clinical outcomes of patients who received a cervical collar after anterior cervical decompression and fusion were evaluated by comparison with those of patients who did not receive a cervical collar. Methods: All of the comparative studies published in the PubMed, Cochrane Library, Medline, Web of Science, and EMBASE databases as of 1 October 2023 were included. All outcomes were analysed using Review Manager 5.4. Results: Four studies with a total of 406 patients were included, and three of the studies were randomized controlled trials. Meta-analysis of the short-form 36 results revealed that wearing a cervical collar after anterior cervical decompression and fusion was more beneficial (P < 0.05). However, it is important to note that when considering the Neck Disability Index at the final follow-up visit, not wearing a cervical collar was found to be more advantageous. There were no statistically significant differences in postoperative cervical range of motion, fusion rate, or neck disability index at 6 weeks postoperatively (all P > 0.05) between the cervical collar group and the no cervical collar group. Conclusions: This systematic review and meta-analysis revealed no significant differences in the 6-week postoperative cervical range of motion, fusion rate, or neck disability index between the cervical collar group and the no cervical collar group. However, compared to patients who did not wear a cervical collar, patients who did wear a cervical collar had better scores on the short form 36. Interestingly, at the final follow-up visit, the neck disability index scores were better in the no cervical collar group than in the cervical collar group. PROSPERO registration number: CRD42023466583. [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]

Wakes produced by underwater vehicles, particularly submarines, in density-stratified fluids play a pivotal role across military, academic, and engineering domains. In comparison to homogeneous fluid environments, wakes in stratified flows exhibit distinctive phenomena, including upstream blocking, pancake eddies, internal waves, and variations in hydrodynamic performance. These phenomena are crucial for optimizing the operation of underwater vehicles. This review critically assesses the hydrodynamic and thermodynamic aspects of these wakes through an integration of theoretical, experimental, and numerical approaches. The hydrodynamic wake evolution, comprising near-wake, non-equilibrium, and quasi-two-dimensional regimes, is scrutinized. The underlying physics, encompassing energy transformation, vertical motion suppression, and momentum dissipation, are analyzed in detail. Special emphasis is placed on numerical methods, encompassing diverse approaches and turbulence models and highlighting their differences in fidelity and computational cost. Numerical simulations not only provide insights into the intricate interplay among various factors but also emerge as a crucial focal point for future research directions. In the realm of thermodynamic wakes, we delve into the thermal wake induced by the discharge of high-temperature cooling water and the cold wake resulting from the stirring of seawater. The generation, evolution, and ascent to the free surface of these wakes are explored. Additionally, this review identifies and analyzes current research shortcomings in each aspect. By systematically addressing existing knowledge gaps, our study contributes novel insights that propel academic progress and bear significant implications for submarine engineering. This work not only enhances our understanding of the intricate dynamics involved but also provides a foundation for future research endeavors in this critical field. [ABSTRACT FROM AUTHOR]

In April 2023, a critically endangered plant species called Plantago fengdouensis was rediscovered on an island in the Yangtze River in Sichuan, China. This species is endemic to the Yangtze River Basin and was previously thought to be extinct in the wild due to the construction of the Three Gorges Dam. However, two previously unknown populations of the plant were found in January 2024 on two islands in the Yangtze River. Efforts are being made to protect these populations and conduct further surveys to locate any other wild populations. Seeds have been collected for ex situ conservation and genetic investigation, with the aim of potentially reintroducing the species. [Extracted from the article]

Luobuma tea is made from the leaves of Apocynum hendersonii (Bt) and A. venetum (Ht) and has been used for a very long time in China and Japan as herbal tea. This study isolated water-soluble polysaccharides from the two species` teas. Physicochemical properties, structural properties, in vitro and in vivo antioxidant and immunomodulatory activities were determined for the first time. The results showed that the Bt and Ht polysaccharides with molecular weights of 31.21 and 49.11 kDa, respectively, composed of arabinose, galactose, rhamnose, glucose, xylose, fucose, and mannose. A dose-dependent nitric oxide production and interleukin-6 inhibitory effects were obtained. Also, they suppressed the expression of cyclooxygenase-2, tumor necrosis factor-α and interleukin-6 mRNA in LPS-induced RAW 264.7 macrophages. Likewise, Bt and Ht have significantly reduced edema in the paws of mice after carrageenan injection. These results suggested that the Luobuma teas polysaccharides can be explored as potential antioxidants and anti-inflammatory agents., Competing Interests: Declaration of competing interest The authors declare no known competing financial interests or relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. 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.)

Lumbar disc herniation (LDH) is a clinically common degenerative disease of the spine, and spinal-pelvic sagittal balance and paravertebral muscle degeneration have been a research focus in recent years. To explore the relationship between the degeneration of paravertebral muscle and the changes in the spinal-pelvic sagittal parameters in LDH patients, 105 LDH patients (experimental group) and 63 healthy volunteers (control group) hospitalized in Ordos Central Hospital from January 2020 and January 2023 were included as study subjects. All the patients underwent lumbar magnetic resonance imaging and spinal X-ray using uniform criteria. The correlation between the paravertebral muscle and sagittal-pelvic sagittal parameters of the patients with LDH was obtained from two imaging examinations, and the data were organized and grouped to explore the correlation between these parameters. No significant difference in general data existed between the groups (P > 0.05). In the L4/5 LDH patients group, the ratio of fat infiltration (FIR) in the healthy side [multifidus (MF) and erector spinae (ES)] was negatively correlated with the lumbar lordosis (LL) (r = -0.461, r = -0.486, P < 0.05). The relative cross-sectional area (RCSA) of the bilateral MF was positively correlated with the pelvic tilt (r = 0.549, r = 0.515, P < 0.05). The bilateral ES RCSA was negatively correlated with the sagittal vertical axis (r = -0.579, r = -0.621, P < 0.05). A positive correlation existed between the RCSA and thoracic kyphosis in the healthy side ES (r = 0.614, P < 0.05). In the L5/S1 LDH patients group, a negative correlation existed between the FIR and LL in the healthy side ES (r = -0.579, P < 0.05). Thus, the paravertebral muscle parameters were correlated with the spinal-pelvic sagittal parameters in the patients with LDH., (© 2024. The Author(s).)