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Conventional multi-scroll chaotic systems are often constrained by the number of attractors and the complexity of generation, making it challenging to meet the increasing demands of communication and computation. This paper revolves around the modified Chua’s system. By modifying its differential equation and introducing traditional nonlinear functions, such as the step function sequence and sawtooth function sequence. A nested grid multi-scroll chaotic system (NGMSCS) can be established, capable of generating nested grid multi-scroll attractors. In contrast to conventional grid multi-scroll chaotic attractors, scroll-like phenomena can be initiated outside the grid structure, thereby revealing more complex dynamic behavior and topological features. Through the theoretical design and analysis of the equilibrium point of the system and its stability, the number of saddle-focused equilibrium points of index 2 is further expanded, which can generate (2 N+2) × M attractors, and the formation mechanism is elaborated and verified in detail. In addition, the generation of an arbitrary number of equilibrium points in the y-direction is achieved by transforming the x and y variables, which can generate M×(2 N+2) attractors, increasing the complexity of the system. The system’s dynamical properties are discussed in depth via time series plots, Lyapunov exponents, Poincaré cross sections, 0–1 tests, bifurcation diagrams, and attraction basins. The existence of attractors is confirmed through numerical simulations and FPGA-based hardware experiments.

The assessment of ecosystem health at the scale of a large river basin is currently an important direction in environmental science and landscape ecology research. This study focuses on the ecological health assessment of the Qinghe River Basin. Following the Guidelines for Eco-health Assessment of Basin (Trial), a framework was designed to construct an assessment system. The aquatic and terrestrial systems of the Basin were selected, and the ecological pattern, ecological function, and ecological pressure were evaluated. The comprehensive assessment index, i.e., whole health index (WHI), was used to evaluate the overall situation of the basin, providing a comprehensive reflection of its state. The results indicate that the comprehensive index of ecological health assessment for the Qinghe River Basin is 58.66, indicating an average evaluation grade. By evaluating the health of the ecological system in the Qinghe River Basin, this study has gained an understanding of the current situation and identified major issues in the area. The study also proposes suggestions for future sustainable development and effective management of the Qinghe River Basin. These findings hold significant practical importance for the comprehensive protection and development of the area. HIGHLIGHTS Adopting a comprehensive assessment framework, including aquatic and terrestrial ecosystems, using the whole health index for comprehensive assessment.; The evaluation covers the entire Qinghe River Basin, providing a comprehensive understanding and evaluation.; Provided theoretical and practical guidance for sustainable development.; The evaluation results provide decision-making basis for policymakers.;

The electrochemical reduction of CO2 (CO2RR) into valuable chemicals and fuels is a promising approach for sustainable energy storage and compromising greenhouse gas emissions, among which the formation of higher-valued multi-carbon products (C2+) is desired. However, selective CO2RR to C2+ usually suffers from a low reaction rate and low selectivity for the complex and long pathways. More seriously, the catalytic system involving catalyst, interface and microenvironment changes dynamically at realistic working conditions, which regrettably causes misleading results regarding the promoted factor and reaction mechanism of CO2RR. To this regard, it is necessary to develop the advanced in situ techniques to track the dynamic evolution of the catalytic system under operating conditions. Here, we discuss the necessary factors and key challenges in producing C2+ products, including current state-of-the-art copper-based catalyst, as well as the dynamic evolution of the catalyst structure, oxidation state and composition. Then, we present the strategies using advanced in situ and operando characterizations to monitor the deep triggers of dynamic evolution and deeply understand the reaction mechanism. Finally, we highlight how the cross-coupled model and data-driven flow enable the new paradigm of in situ characterization with higher accuracy and efficiency.

The density and surface tension for the aqueous solution of amino acids ionic liquid (AAIL) 1-pentyl-3-methylimidazolium glycinate salt [C5mim] [Gly] with various molalities were measured at T = (288.15 to 318.15) K with an interval of T = 5 K, and based on the experimental values, the molar surface Gibbs energy of the ionic liquid solution was obtained, in addition, the relationship between the molar surface Gibbs energy and molalities was explored.

The application of domestic sewage sludge (SS) may affect plant growth and soil quality through altering nutrient availability. However, the effect of SS application on the plant–soil system in sandy soils is poorly understood. In this study, we established SS application treatment plots (SL, 25 t ha−1) and control treatment plots without sewage sludge application (CK, 0 t ha−1). SS was applied to the soil surface of a Mongolian pine (Pinus sylvestris var. mongolica) plantation in Horqin Sandy Land, Inner Mongolia, China, to assess its potential effects on plants and soil. We analyzed tree growth performances (tree height, basal diameter, and diameter at breast height), understory traits (species diversity, coverage, and aboveground biomass), soil physical and chemical parameters (nutrient content, dissolved organic carbon, soil water content, bulk density, pH), and proxies of ecosystem services (soil organic carbon and total nitrogen stocks). The results showed that SS addition not only significantly increased soil nutrient contents, but also markedly enhanced aboveground productivity and plant coverage. Specifically, SS addition decreased soil bulk density and increased concentrations of soil organic carbon, total nitrogen, and total phosphorus and mineral nitrogen, and it also increased soil carbon and nitrogen stocks. Furthermore, the addition of SS significantly increased soil dissolved organic carbon contents and enhanced the fluorescence intensities of dissolved organic carbon components (humic acid-like and UV fulvic acid-like) in the topsoil (0–5 cm). This study provides evidence that SS is an acceptable, and possibly preferred organic fertilizer for improving the soil quality and tree–grass growth of Mongolian pine plantations.

Humic acid (HA) is extremely important for understanding the geochemical cycle of pollutants in different environments. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) has performed molecular-level analysis of two standard HAs from the Suwannee River (SRHA) and leonardite (LEHA) and HA from Jiufeng forest in Beijing (JFHA), which is impossible for other conventional instruments. Regardless of the source of HA, compounds containing more heteroatoms (such as nitrogen and sulfur) have a higher degree of unsaturation and aromaticity. JFHA, SRHA, and LEHA from soil, river, and leonardite, respectively, are arranged in order from the lowest to highest degree of humification, according to molecular unsaturation and aromaticity of HAs. Soil HA is more labile and contains many large molecular weight compounds with low unsaturation. Regardless of unsaturation, molecules of River HA have a homogeneous molecular mass distribution and contain many plant-derived lignin- and tannin-like compounds, which are more stable than lipid and more labile than condensed aromatics. Leonardite HA with a high degree of humification contains a large number of compounds with high aromaticity and more heteroatoms and has low lability. Our results reveal the diversity of humic acid at molecular level because of different degree of humification and the lability. These conclusions are significant for understanding the role of humic acid from different sources in pollutant transformation and the geochemical cycle at the molecular level.

Few attempts have been made to study the alleviating effects of signal molecules on zoysiagrass (Zoysiajaponica) under drought stress. Calcium chloride has been shown to ameliorate the adverse effects of drought stress on many plants. It is necessary to investigate how to enhance drought tolerance of zoysiagrass using calcium chloride. The study elucidated the effects of calcium chloride on zoysiagrass under drought conditions by investigating the following parameters: biomass, chlorophyll (Chl) content, net photosynthetic rate (Pn), chlorophyll fluorescence, antioxidant enzymes, proline content, and malondialdehyde (MDA) content. Experimental conditions consisted of an aqueous CaCl2 solution at 5, 10, and 20 mM sprayed on zoysiagrass leaves for 3 d, following by an inducement of drought conditions by withholding water for 16 d. Under drought conditions, all CaCl2 pretreatments were found to increase the above-ground fresh biomass, as well as below-ground fresh and dry biomass. The resulting Chl (a, b, a+b) contents of the 5 and 10 mM CaCl2 pretreatment groups were higher than those of the control. In the later stages of drought conditions, the chlorophyll fluorescence parameter Fv/Fm was higher in leaves treated with 10 mM CaCl2 than in the leaves of the other two treatment groups. Zoysiagrass pretreated with 10 mM CaCl2 possessed both the maximum observed Pn and antioxidant enzyme activities. Meanwhile, lower MDA and proline contents were recorded in the plants pretreated with 5 and 10 mM CaCl2 under drought conditions. As a whole, the drought tolerance of zoysiagrass was improved to some extent by the application of a moderate calcium concentration.

Atherosclerosis (AS) is a significant global health concern due to its high morbidity and mortality rates. Extensive efforts have been made to replicate the cardiovascular system and explore the pathogenesis, diagnosis, and treatment of AS. Microfluidics has emerged as a valuable technology for modeling the cardiovascular system and studying AS. Here a brief review of the advances of microfluidic-based cardiovascular systems for AS research is presented. The critical pathogenetic mechanisms of AS investigated by microfluidic-based cardiovascular systems are categorized and reviewed, with a detailed summary of accurate diagnostic methods for detecting biomarkers using microfluidics represented. Furthermore, the review covers the evaluation and screening of AS drugs assisted by microfluidic systems, along with the fabrication of novel drug delivery carriers. Finally, the challenges and future prospects for advancing microfluidic-based cardiovascular systems in AS research are discussed and proposed, particularly regarding new opportunities in multi-disciplinary fundamental research and therapeutic applications for a broader range of disease treatments. [ABSTRACT FROM AUTHOR]

Peripheral nerve injury is a major challenge in clinical treatment due to the limited intrinsic capacity for nerve regeneration. Tissue engineering approaches offer promising solutions by providing biomimetic scaffolds and cell sources to promote nerve regeneration. In the present work, we investigated the potential role of skin-derived progenitors (SKPs), which are induced into neurons and Schwann cells (SCs), and their extracellular matrix in tissue-engineered nerve grafts (TENGs) to enhance peripheral neuroregeneration. SKPs were induced to differentiate into neurons and SCs in vitro and incorporated into nerve grafts composed of a biocompatible scaffold including chitosan neural conduit and silk fibroin filaments. In vivo experiments using a rat model of peripheral nerve injury showed that TENGs significantly enhanced nerve regeneration compared to the scaffold control group, catching up with the autograft group. Histological analysis showed improved axonal regrowth, myelination and functional recovery in animals treated with these TENGs. In addition, immunohistochemical staining confirmed the presence of induced neurons and SCs within the regenerated nerve tissue. Our results suggest that SKP-induced neurons and SCs in tissue-engineered nerve grafts have great potential for promoting peripheral nerve regeneration and represent a promising approach for clinical translation in the treatment of peripheral nerve injury. Further optimization and characterization of these engineered constructs is warranted to improve their clinical applicability and efficacy.

A central question in neural tissue engineering is how the tissue-engineered nerve (TEN) translates detailed transcriptional signals associated with peripheral nerve regeneration into meaningful biological processes. Here, we report a skin-derived precursor-induced Schwann cell (SKP-SC)-mediated chitosan/silk fibroin-fabricated tissue-engineered nerve graft (SKP–SCs-TEN) that can promote sciatic nerve regeneration and functional restoration nearly to the levels achieved by autologous nerve grafts according to behavioral, histological, and electrophysiological evidence. For achieving better effect of neuroregeneration, this is the first time to jointly apply a dynamic perfusion bioreactor and the ascorbic acid to stimulate the SKP-SCs secretion of extracellular matrix (ECM). To overcome the limitation of traditional tissue-engineered nerve grafts, jointly utilizing SKP-SCs and their ECM components were motivated by the thought of prolongating the effect of support cells and their bioactive cues that promote peripheral nerve regeneration. To further explore the regulatory model of gene expression and the related molecular mechanisms involved in tissue engineering-aided peripheral nerve regeneration, we performed a cDNA microarray analysis of gene expression profiling, a comprehensive bioinformatics analysis and a validation study on the grafted segments and dorsal root ganglia tissues. A wealth of transcriptomic and bioinformatics data has revealed complex molecular networks and orchestrated functional regulation that may be responsible for the effects of SKP-SCs-TEN on promoting peripheral nerve regeneration. Our work provides new insights into transcriptomic features and patterns of molecular regulation in nerve functional recovery aided by SKP-SCs-TEN that sheds light on the broader possibilities for novel repair strategies of peripheral nerve injury.

Environmental context: Novel insight into BEOMcc is provided by fractionation and FTICR MS. Sub-fractions of biochar were extracted due to the chemical properties of the organic solvents. BEOMcc has a carbon fixation effect, and so is likely beneficial to the growth of plants and microorganisms. Rationale: Since carbon disulfide (CS2) has a strong penetrating ability and acetone (CH3COCH3) can dissolve tiny biochar particles, a mixture of these compounds may efficiently extract organic matter from biochar. The extraction efficacy and structural features of a mixture of CH3COCH3 and CS2 (1:1) were tested in this study. Π-Π interactions between CS2 and CH3COCH3 increase the solubility of organic matter in the extraction process. Methodology: We used a mixture of CH3COCH3 and CS2 (1:1) to extract organic matter from soybean straw biochar (BEOMcc) and applied Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) for analysis. Results: We found that CS2/CH3COCH3 tended to extract refractory substances, and the resulting extract contained a higher number of heteroatoms than the CS2-extractable fraction (1.34 times). Discussion: The H/C ratio of BEOMcc is lower than that of CS2- and CH3COCH3-extractable components. The aromatic component of BEOMcc accounts for 52.47%, which is higher than the contribution to CS2-extractable organic matter of approximately 49.9%. The polycyclic aromatic hydrocarbon component of BEOMcc is beneficial to improving soil stability. The organic matter fraction of BEOMcc has a lower H/C ratio. The C/N ratio of BEOMcc is lower than that of the CS2- and CH3COCH3-extractable components. This result reveals that BEOMcc may provide a significant environmental benefit. The polarity of BEOMcc is between that of CS2- and CH3COCH3-extractable components. Implications for future research: In this study, the composition of BEOMcc was assessed at the molecular level, and the extraction method was continuously improved to provide more extraction options for the study of biochar-pollutant interactions. This method can be used to extract organic matter that is difficult to extract by conventional methods, which is more closely bound to the biochar framework. It can provide a technical basis for the in‐depth characterisation and utilisation of biochar organic matter. [ABSTRACT FROM AUTHOR]

Neural tissue engineering techniques typically face a significant challenge, simulating complex natural vascular systems that hinder the clinical application of tissue-engineered nerve grafts (TENGs). Here, we report a subcutaneously pre-vascularized TENG consisting of a vascular endothelial growth factor-induced host vascular network, chitosan nerve conduit, and inserted silk fibroin fibers. Contrast agent perfusion, tissue clearing, microCT scan, and blood vessel 3D reconstruction were carried out continuously to prove whether the regenerated blood vessels were functional. Moreover, histological and electrophysiological evaluations were also applied to investigate the efficacy of repairing peripheral nerve defects with pre-vascularized TENG. Rapid vascular inosculation of TENG pre-vascularized blood vessels with the host vascular system was observed at 4 ​d bridging the 10 ​mm sciatic nerve defect in rats. Transplantation of pre-vascularized TENG in vivo suppressed proliferation of vascular endothelial cells (VECs) while promoting their migration within 14 ​d post bridging surgery. More importantly, the early vascularization of TENG drives axonal regrowth by facilitating bidirectional migration of Schwann cells (SCs) and the bands of Büngner formation. This pre-vascularized TENG increased remyelination, promoted recovery of electrophysiological function, and prevented atrophy of the target muscles when observed 12 weeks post neural transplantation. The neural tissue-engineered pre-vascularization technique provides a potential approach to discover an individualized TENG and explore the innovative neural regenerative process.

The strategic exploration of urban sports tourism resources and the pursuit of novel trajectories for urban growth are pivotal for resource integration and competitive enhancement within cities. This investigation concentrates on Chinese city marathons and compiles daily search index data from Baidu for 38 city marathons across the nation, spanning from January 1st, 2012 to May 3rd, 2022. Employing time series clustering to evaluate the data, and in conjunction with indices related to urban tourism resources and city development, we delve into the characteristics of how Chinese city marathons propel urban growth. The findings illustrate that the search index data for the 38 city marathons can be clustered into three categories, with Xi'an, Fuzhou, and Dalian emerging as the epicenters of clustering. The representative search index data for these three clusters reveal diverse characteristics of change. The search index shifts for three landmark races align generally with the changes observed in their respective cluster center races, however, variations exist among the search index changes for these iconic marathons. The degree of search index and its trending direction in city marathons emanate from the synergistic influence of the city's political, economic, and tourism attributes, in addition to the event's prominence. City marathons also catalyze urban development through economic stimulation, image enhancement, and infrastructure improvement. Future exploration of novel trajectories for urban development could be facilitated through harnessing the economic and tourism attributes of these events, and by orchestrating a unified series of marathons.

The molecular network features of spinal cord development that are integral to tissue engineering remain poorly understood in placental mammals, especially in terms of their relationships with vital biological processes such as regeneration. Here, using a large-scale temporal transcriptomic analysis of rat spinal cord from the embryonic stage to adulthood, we show that fluctuating RNA expression levels reflect highly active transcriptional regulation, which may initiate spinal cord patterning. We also demonstrate that microRNAs (miRNAs) and transcriptional factors exhibit a mosaic profile based on their expression patterns, while differential alternative splicing events reveal that alternative splicing may be a driving force for the development of the node of Ranvier. Our study also supports the existence of a negative correlation between innate immunity and intrinsic growth capacity. Epigenetic modifications appear to perform their respective regulatory functions at different stages of development, while guanine nucleotide-binding protein (G protein)-coupled receptors (including olfactory receptors (ORs)) may perform pleiotropic roles in axonal growth. This study provides a valuable resource for investigating spinal cord development and complements the increasing number of single-cell datasets. These findings also provide a genetic basis for the development of novel tissue engineering strategies.