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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]

For a multi-agent system (MAS) with a directed weighted chain graph, this article studies the effect of adding reverse edges on its convergence rate. The introduction of weights leads to our research being more complex and challenging. Firstly, for the case of one reverse edge, there are two completely opposite conclusions about the effect of adding one reverse edge on the convergence rate under certain conditions, which is dependent on whether the end node of the reverse edge is the root node of the chain graph or not. Subsequently, we discuss the relative positions of two reverse edges in three cases and obtain the convergence rate of the whole network is determined by the ranges, the relative positions of these two reverse edges, and the sizes and distribution of weights in the directed weighted graph. Moreover, as the number of reverse edges increases, we overcome the complex relationships among multiple reverse edges and establish similar theories. Finally, some numerical examples are given to illustrate our main theorems. Our results generalise the results from unweighted directed graph to a weighted directed graph. [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]

The optimal allocation of educational resources has been a hot issue, and exploring the accessibility of educational facilities in poor mountainous areas helps to reasonably plan the layout of educational facilities and promote the balanced development of education. Taking the rocky desertification area in Yunnan, Guangxi, and Guizhou (YGGRD) as the study area, based on the POI data of educational facilities in the YGGRD in 2000, 2010 and 2019, this study explored the evolution of the accessibility of educational facilities in the YGGRD through raster accessibility. And the influencing factors were analyzed by the ordinary least square method (OLS) and geographically weighted regression model (GWR), and evaluated the model through cross validation. The results show that the overall accessibility of educational facilities improved significantly from 2000 to 2019. Educational facilities mainly have good accessibility and average accessibility. Poor accessibility areas are concentrated in the interprovincial border regions, and the boundary effect is significant. County accessibility, population density and rural per capita disposable income have a great impact on the accessibility of educational facilities in the YGGRD. It is suggested to strengthen the construction of educational facilities in the interprovincial border regions, relocate and integrate villages, and improve the education quality of township schools to improve the supply of rural educational resources. [ABSTRACT FROM AUTHOR]

Background: The efficacy of virtual reality (VR)-based intervention for improving cognition in patients with the chronic stage of stroke is controversial. The aims of this meta-analysis were to evaluate the effect of VR-based training combined with traditional rehabilitation on cognition, motor function, mood, and activities of daily living (ADL) after chronic stroke. Methods: The search was performed in the Cochrane Library (CENTRAL), EBSCO, EMBASE, Medline (OVID), Web of Science databases, PubMed, CINAHL Ovid, and Scopus from inception to May 31, 2021. All included studies were randomized controlled trials (RCTs) examining VR-based intervention combined with traditional rehabilitation for chronic stroke. The main outcomes of this study were cognition, including overall cognition (combined with all cognitive measurement results), global cognition (measured by the Montreal Cognitive Assessment, MoCA, and/or Mini-Mental State Examination, MMSE), and attention/execution. The additional outcomes were motor function, mood, and ADL. Subgroup analyses were conducted to verify the potential factors for heterogeneity. Results: Six RCTs including 209 participants were included for systematic review, and five studies of 177 participants were included in meta-analyses. Main outcome analyses showed large and significant effect size (ES) of VR-based training on overall cognition (g = 0.642; 95% CI = 0.134–1.149; and P = 0.013) and attention/execution (g = 0.695; 95% CI = 0.052–1.339; and P = 0.034). Non-significant result was found for VR-based intervention on global cognition (g = 0.553; 95% CI = −0.273–1.379; and P = 0.189). Additional outcome analyses showed no superiority of VR-based intervention over traditional rehabilitation on motor function and ADL. The ES of VR-based intervention on mood (g = 1.421; 95% CI = 0.448–2.393; and P = 0.004) was large and significant. In the subgroup analysis, large effects for higher daily intensity, higher weekly frequency, or greater dose of VR intervention were found. Conclusion: Our findings indicate that VR-based intervention combined with traditional rehabilitation showed better outcomes for overall cognition, attention/execution, and depressive mood in individuals with chronic stroke. However, VR-based training combined with traditional rehabilitation showed a non-significant effect for global cognition, motor function, and ADL in individuals with chronic stroke. [ABSTRACT FROM AUTHOR]

Ginsenosides Rb1, Rb2, Rb3 and Rc, four major protopanaxadiol (PPD)‐type ginsenosides, can be metabolized by gut microbiota. The composition of gut microbiota varies in different species. Existing publications have reported the metabolite fates of ginsenosides by gut microbiota from single species. However, their microbiota‐related metabolic species differences have not been evaluated yet. In current study, in vitro anaerobic incubations of PPD‐type ginsenosides with gut microbiota from humans, rabbits and rats were conducted. The metabolites of each ginsenoside were then identified by LC–MS. A total of 15 metabolites from the four ginsenosides were identified. The major metabolic pathways were stepwise removals of the C‐20 and C‐3 sugar moieties to obtain aglycone PPD. The results showed that the hydrolysis rate of C‐20 terminal β‐D‐glucopyranosyl was significantly higher than those of α‐L‐arabinopyranosyl, β‐D‐xylopyranosyl and α‐L‐arabinofuranosyl in different species. The activity of β‐glucosidase, the metabolic rates of parent compounds and the formation rates of their metabolites were significantly higher in gut microbiota from rabbits than from humans and rats. Our research draws researchers' attention to the species differences of microbiota‐related drug metabolism. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the potential diagnostic value of miR‐214, B‐type natriuretic peptide (BNP), N terminal‐pro BNP (NT‐proBNP) and soluble ST2 (sST2) in acute heart failure (AHF). Method: This study included 176 patients as the AHF group and 60 healthy subjects as the control group from February 2018 to February 2020. Patients in the AHF group were classified according to the New York Heart Association (NYHA) functional classification, including 60 level II patients, 59 level III patients and 57 level IV patients. The expression level of miR‐214, BNP, NT‐proBNP and sST2 of both groups were recorded and analysed. Results: The morbidity of cardiovascular diseases was significantly higher in the AHF group than in the control group (P <.05). The expression level of miR‐214, BNP, NT‐proBNP and sST2 in the AHF group were all significantly higher than in the control group (P <.05). Besides, the expression level of all the molecules in level IV was significantly higher than that of level III and level II, respectively (P <.001, P <.001). In addition, the expression level of all the molecules in level III was significantly higher than that of level II (P <.001). The area under the ROC curve of miR‐214, BNP, NT‐proBNP and sST2 were 0.913, 0.836, 0.849 and 0.855, respectively, indicating good diagnostic value. Conclusion: MiR‐214, BNP, NT‐proBNP and sST2 can be used as effective biomarkers for AHF, providing a new strategy for diagnosis and for judging the severity of AHF. [ABSTRACT FROM AUTHOR]

An efficient and chemoselective synthesis of sulfoxides through the electrooxidation of sulfides has been well developed. This protocol takes advantage of electricity as the terminal oxidant and of molecular oxygen and water as the oxygen atom sources. A variety of structurally diverse sulfoxide compounds are assembled in moderate to excellent yields. The scaled‐up reactions at 6–20 mmol show the good practicability and application potential of this methodology. A possible free radical mechanism has been proposed to rationalize the reaction procedure. [ABSTRACT FROM AUTHOR]

Braiding carriers, which are the important parts of a braiding machine, have the functions such as carrying braiding materials, controlling tension of carbon fiber, and driving carbon fiber movement. During the braiding process, two groups of carbon fibers braided in clockwise and counter clockwise direction contact each other and form relative motion, which causes friction and fuzzing. In order to improve this situation, the structural parameters of the carriers need to be optimized. In this paper, the kinematics and dynamics models were established based on the structure of braiding carriers. The micro-element method was used to analyze the relationship between the fiber length released from the yarn barrel, the rotation angle of the lever, and the tension of the carbon fiber. To limit the fluctuant range of carbon fiber tension, and to alleviate the fluffing phenomenon caused by the two groups of carbon fiber in contact with each other, antlion algorithm was used to optimize the structural parameters of braiding carriers. The simulation results showed that the tension of the carbon fiber can meet the processing requirements by adjusting the starting angle of each stage of carrier, the length of lever, the elastic coefficient of springs, and pre-compression of springs. It can be known that the structural parameters of braiding carriers optimized by antlion algorithm could meet the requirement of carbon fiber tension. [ABSTRACT FROM AUTHOR]

In this study, we attempt to analyze the influence of different excitation factors on the dynamic behavior of a gear transmission system in a braiding machine. In order to observe nonlinear characteristics, a mathematical model is established with a six-degrees-of-freedom gear system for consideration of multiple excitation factors. Iterative results are used to study the nonlinear characteristics of the gear system with respect to contact temperature, varying levels of friction, and disturbance of yarn tension using bifurcation diagrams, maximum Lyapunov exponents, phase diagrams, Poincare maps, and the power spectrum. The numerical results show that excitation factors such as temperature and surface friction, among others, have considerable influence on the nonlinear characteristics of the gear system in a braiding machine, and the model is evaluated to show the key regions of sensitivity. The analysis of associated parameters can be helpful in the design and control of braiding machines. [ABSTRACT FROM AUTHOR]

Multiferroic properties of La-modified four-layered perovskite BiLaFeCoTiO (0 ≤ x ≤ 1) ceramics were investigated, by analyzing the magnetodielectric effect, magneto-polarization response and magnetoelectric conversion. X-ray diffraction indicated the formation of pure Aurivillius ceramics, and Raman spectroscopy revealed the Bi ions displacement and the crystal structure variation. The enhancement of ferromagnetic and ferroelectric properties was observed in BiLaFeCoTiO after La modification. The evidence for enhanced ME coupling was determined by magnetic field-induced marked variations in the dielectric constant and polarization. A maximum ME coefficient of 1.15 mV/cm·Oe was achieved in BiLaFeCoTiO ceramic, which provides the possible promise for novel magnetoelectric device application. [ABSTRACT FROM AUTHOR]

Lead-free magnetoelectric (ME) laminated (80Bi0.5Na0.5TiO3-20Bi0.5K0.5TiO3)/(Ni0.8Zn0.2)Fe2O4 (BNKT/NZFO) composites are prepared via a modified cofiring processing, combining grain refinement and liquid phase sintering with low sintering aid content. The microstructure, dielectric, ferroelectric, magnetic, and magnetoelectric properties are investigated by varying the thickness of NZFO layer. The results show that the coexistence of independent BNKT and NZFO phase and the presence of the morphotopic phase boundary in BNKT phase with high piezoelectric coefficient d33 of 131 pC/N are confirmed. Laminated composites have clear and well-bonded interfaces across the two layers, as well as improved ME properties. The maximum ME voltage coefficient ( αE31) of the laminated composite reach 115.1 mV cm−1 Oe−1 with an optimized BNKT/NZFO layer thickness ratio of 1/2. In addition, a zero-biased ME response was observed in BNKT/NZFO laminated composites. [ABSTRACT FROM AUTHOR]

The use of botulinum toxin A (BTX-A) for various clinical therapeutic applications is increasing. It is widely believed that peripheral therapeutic or toxic effects of BTX-A are exclusively mediated by SNAP-25 cleavage. There is growing evidence of long-distance retrograde axonal transport of BTX-A on entering the central nervous system, subsequent to a local injection of the toxin. However, the prevalence of central antinociceptive effects after BTX-A peripheral application and its underlying mechanisms are unclear. Our results show that (1) BTX-A can undergo retrograde axonal transport to the dorsal horn after peripheral application; (2) Peripheral pretreatment with BTX-A decreases the expression and function of AMPA receptors in the spinal cord dorsal horn neurons; (3) Peripheral pretreatment with BTX-A does not change basal glutamate release, but decreases the effect of formalin-evoked release of glutamate in spinal cord dorsal horn neurons. These results suggest that peripheral application of BTX-A can change AMPA receptor expression in, and glutamate release from, spinal dorsal horn neurons, which may have significance in its central antinociceptive effects. [ABSTRACT FROM AUTHOR]

[Display omitted] FK506 is a local drug that is commonly used in the treatment of psoriasis. Its clinical application, however, is limited by its transdermal drug delivery rate, the time-consuming, and the greasy therapy. In this study, which was inspired by local block injection used in the clinical treatment for keloid, a hyaluronic acid (HA) based system to transport FK506 into the skin to treat psoriasis, named blocking patch (BP) was developed. BP has a complete appearance, sufficient puncture strength, and is virtually non-irritating in vivo. By confocal fluorescence microscopy, BP loaded with FK506 (FK506-BP) showed satisfactory transdermal release ability in vivo. Further animal studies revealed that FK506-BP showed a good anti-inflammatory ability in the imiquimod (IMQ)-induced mouse psoriasis-like dermatitis and inhibited the activation of associated immune cells. This study indicates that BP as a novel delivery system, realizes an efficient local delivery of FK506 in psoriasis and holds great potential in transdermal delivery. [ABSTRACT FROM AUTHOR]

Abstract: The transcription factor E2F1 is upregulated when cerebellar granular neurons (CGNs) undergo apoptosis under potassium deprivation. In this study, we examined the effects of E2F1 upregulation on the survival and death of CGNs isolated from C57 mice and Sprague-Dawley (SD) rats. Plasmid- and adenovirus-mediated expression of E2F1 dose-dependently induced apoptosis in mouse CGNs but unexpectedly failed to induce apoptosis in rat CGNs. Caspase 3, a marker for neuronal apoptosis, was significantly activated by ectopic E2F1 expression in mouse CGNs but not in rat CGNs. Furthermore, overexpression of E2F1 significantly promoted apoptotic progression in mouse CGNs following potassium deprivation but attenuated apoptosis in rat CGNs, whereas E2F1 lacking DNA binding ability (E2F1-M132) lost its pro-apoptotic role in mouse CGNs and anti-apoptotic role in rat CGNs. Together, our results demonstrated that upregulation of E2F1 by potassium deprivation promotes apoptosis in C57 mouse CGNs but antagonizes apoptosis in SD rat CGNs, suggesting opposing roles for E2F1 in regulating CGN fate. [Copyright &y& Elsevier]

J. Wei recently proposed a concept of *-modules which is another generalization of *-modules besides *-modules [J. Algebra, 2005, 291: 312-324]. In this paper, we consider the co-*-modules and give some characterizations and properties. It is found that the class of co-*-modules contains co-selfsmall injective cogenerators. The relations between co-*-modules and co-*-modules are also considered. [ABSTRACT FROM AUTHOR]

Let R be a ring. A right R-module U is called Tor-tilting if [image omitted], where U+ = Hom(U, /), Cogen(U+) is the class of left R-modules cogenerated by U+ and [image omitted] consists of modules RM such that [image omitted]. Some examples and characterizations of Tor-tilting modules are given. Among others, it is shown that UR is Tor-tilting if and only if U+ is cotilting. Moreover, both tilting modules and completely faithful flat modules are proved to be Tor-tilting. The torsion theory induced by a Tor-tilting module is also investigated. [ABSTRACT FROM AUTHOR]