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With vitamin A acetate as raw material, ethylenediamine retinyl Schiff base salts coordinated with rare earth ion La3+, Ce3+ were synthesized, and the structure of the products was characterized by FT-IR and Raman spectra. The electromagnetic parameters in the frequency range of 2-18 GHz were measured by microwave vector network analyzer, its reflectivity was calculated, and the main factors and mechanism that affect the wave-absorbing performance of rare retinyl Schiff base salts were discussed. The results show that the coordination bond is formed by the rare earth ions and Schiff base. The reflectivity of Schiff base coordinated with La3+ ion is –16 dB at 12.9 GHz (bandwidth with reflectivity better than –10 dB is 3.1 GHz), the reflectivity of Schiff base coordinated with Ce3+ ion is –18.8 dB at 12.7 GHz (bandwidth with reflectivity better than –10 dB is 3.4 GHz). Microwave absorption performances of the both are superior to the wave-absorbing performance of Schiff base coordinated with non-rare earth ions.

In view of problem that existing hydraulic support life estimation method rarely consider continuous performance decline of hydraulic support in use process and leads to great error, a residual life estimation method of components of hydraulic support in service was proposed. Components S -N curve was obtained by correcting material S -N curve through introduction of surface coefficient, structural size coefficient and welding impact coefficient. Then the components S -N curve was used for life estimation according to cumulative damage theory, residual damage capacity and stress spectrum. Multi-level fuzzy evaluation method was used to evaluate the state of hydraulic support roof beam, and overall life coefficient was multiplied by the estimated life to get the residual life of the components of hydraulic support in service. The experimental results show that the estimation error of the proposed method is 3.52% and the precision is high.

Linear cultural heritage—a heritage system spanning time and space—is a large-scale cultural settlement that accommodates various heritage types. Here, we comprehensively explored the Straight Road (Zhidao) of the Qin Dynasty in Shaanxi Province, China, as a gene of traditional cultural connotations and geographical features, and provided holistic conservation strategies and effective utilization paths. From an ecological security pattern perspective, 4399.89 km2 of ecological sources and 19 ecological nodes were identified based on the importance of four ecosystem services—carbon sequestration and oxygen release, water conservation, habitat maintenance, and soil retention. Then, 45 ecological corridors with a total length of 2938.49 km were determined using the minimum cumulative resistance model. The intersections of ecological corridors were distinguished and the key areas of cultural landscape construction were extracted by taking into account the spatial distribution of existing relics as well as the spatial network relationship of prohibited-development areas and existing gray corridors (roads), blue corridors (rivers), and green ecological corridors (shade zones, green belts, recreational greenways). A plan was proposed to construct 98.45 km2 of new parks (country parks: 28.38 km2, forest parks: 70.07 km2) and 101.26 km of new landscape corridors (urban type: 32.08 km, countryside type: 26.49 km, ecological type: 42.69 km). Multilevel landscape complexes should be built to form a functional and networked ecological–cultural spatial structure system. Findings of this study could provide ecological ideas for promoting the reservation and active utilization of linear cultural-heritage corridors on a regional scale. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) and osteoporosis are two distinct diseases but often occur in the same patient. Their relationship remains poorly understood. Studies using Tg2576 AD animal model demonstrate bone deficits, which precede the brain phenotypes by several months, arguing for the independence of bone deficits on brain degeneration and raising a question if the bone deficits contribute to the AD development. To address this question, we investigated the effects of PTH1-34, a peptide of parathyroid hormone analog and a well-recognized effective anabolic therapy drug for patients with osteoporosis, on 5XFAD animal model. Methods: 5XFAD mice, an early onset β-amyloid (Aβ)-based AD mouse model, were treated with PTH1-34 intermittently [once daily injection of hPTH1–34 (50 μg/Kg), 5 days/week, starting at 2-month old (MO) for 2–3 month]. Wild type mice (C57BL/6) were used as control. The bone phenotypes were examined by microCT and evaluated by measuring serum bone formation and resorption markers. The AD relevant brain pathology (e.g., Aβ and glial activation) and behaviors were assessed by a combination of immunohistochemical staining analysis, western blots, and behavior tests. Additionally, systemic and brain inflammation were evaluated by serum cytokine array, real-time PCR (qPCR), and RNAscope. Results: A reduced trabecular, but not cortical, bone mass, accompanied with a decrease in bone formation and an increase in bone resorption, was detected in 5XFAD mice at age of 5/6-month old (MO). Upon PTH1-34 treatments, not only these bone deficits but also Aβ-associated brain pathologies, including Aβ and Aβ deposition levels, dystrophic neurites, glial cell activation, and brain inflammatory cytokines, were all diminished; and the cognitive function was improved. Further studies suggest that PTH1-34 acts on not only osteoblasts in the bone but also astrocytes in the brain, suppressing astrocyte senescence and expression of inflammatory cytokines in 5XFAD mice. Conclusions: These results suggest that PTH1-34 may act as a senolytic-like drug, reducing systemic and brain inflammation and improving cognitive function, and implicate PTH1-34's therapeutic potential for patients with not only osteoporosis but also AD. [ABSTRACT FROM AUTHOR]

Professor Wang Ning is a visionary Chinese literary theorist and comparatist who has played a prominent role in both Chinese and international academic debates about the construction of world literature and global humanities. This article revisits his evolving theories on world literature, discusses his emphasis on the necessity of a tripartite translation strategy in the formation of a more democratic world literary system from a Chinese perspective, scrutinises his historical approach to understanding Chinese literature in relation to the Nobel Prize in Literature, and the importance of literary film adaptation after the world's turn to the visual. As a world-class literary theorist, Prof. Wang Ning has had a profound influence on Chinese humanities scholars who write in both Chinese and English, compelling us to ponder over how to practice his cosmopolitan spirit and join him in advancing China's scholarship in the age of globalisation. [ABSTRACT FROM AUTHOR]

To investigate how different core and end-capping moieties affect the thin-film morphology and memory performance of star-shaped molecules, five molecules BPPT, TPPT, TPPA, t Bu-TPPT and t Bu-TPPA were synthesized, which consist of the same branched groups, but have different core units with different electronic effects, namely, 1,3,5-triphenylbenzene, 2,4,6-triphenyl-1,3,5-triazine and triphenylamine. Among them, the devices based on TPPT, TPPA, t Bu-TPPT and t Bu-TPPA containing nitrogen heteroatoms show nonvolatile binary write-once-read-many-times (WORM) memory behaviours. Notably, the t Bu-TPPA based devices display the highest ION/IOFF ratio (105) and the lowest threshold voltage (1.45 V). We propose that the resistive switching characteristic of these materials is due to the Al filament conduction mechanism induced by N atoms. These results suggest that introducing the N heteroatoms into molecules can not only adjust the intermolecular interactions and thin film morphology, but also help to the formation of metal filament, which thus changes the resistive memory behaviour. Due to its dependable and stable storing properties, the as-fabricated WORM device based on t Bu-TPPA was also applied to the operation of logic gates and information displays, showing significant potential for national security and patient confidentiality in hospitals. [ABSTRACT FROM AUTHOR]