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• PAFG with activation of low concentration PA were successfully prepared. • The formation of geopolymer gels of Si-O-Al-O-P, Al-O-P, or Si-O-P were the primary reaction products and strength gain for PAFG samples. • The CO 2 emission and energy consumption of PAFG were much lower than that of AAFG and PC pastes. • The PAFG was more expansive due to the expansive PA solution. Phosphoric acid (PA)-activated geopolymer is a potential construction material with superior mechanical performance and high temperature resistance. However, the synthesis of phosphoric acid-activated fly ash (FA) geopolymer (PAFG) usually requires high concentrations of PA. In this study, the mechanical properties and microstructure of PAFG samples prepared with varying low PA concentrations (LPA, 1–4 M), liquid/FA ratios (0.3–0.45), and curing temperatures (25, 60, 90 °C), as well as their effects on the environment and economy, were investigated. The compressive strengths of PAFG with activation of LPA were generally low. The PAFG prepared with a L/F = 0.35 and 4 M PA solution curing at 60 °C for 6 days obtained the highest compressive strength of 13.23 MPa. The formation of geopolymer gels of Si-O-Al-O-P, Al-O-P, or Si-O-P were the primary reaction products and strength gain for PAFG samples. The increase in PA concentration and L/F ratio accelerated the FA dealumination reaction and the polymerization reaction by increasing the H+ and P-O concentrations of solution. In comparison to low concentration NaOH-activated fly ash geopolymer and cement pastes, the CO 2 emission intensity and energy consumption intensity of PAFG curing at 25 °C were reduced by 70.9% and 35.6%, and 90.6% and 90.6%, respectively. Albeit the cost increased by 87.4% and 30.7%, respectively. Therefore, it is essential to develop inexpensive chemical processes for the preparation of PA solutions. [ABSTRACT FROM AUTHOR]

Historical records, e.g., herbarium vouchers, contain information about species distribution since the early days of the scientific exploration of floras until today. These data provide crucial evidence to map the biodiversity of the area of interest and most importantly enable the evaluation of the conservation effectiveness for a given group of organisms. This study aimed to explore the ferns and lycophytes' diversity of Xishuangbanna Dai Autonomous Prefecture in tropical China with special emphasis on conservation efforts provided by the currently established protected areas (PAs). Instead of relying exclusively on current observation, the database was compiled from digitalized herbarium vouchers and publications being explored with special attention on the temporal and spatial dimensions of collecting efforts. Utilizing the indices including species richness, weighed endemism, corrected weighted endemism, and beta diversity, hotspots of ferns and lycophytes' diversity were identified. In turn, the proportion of hotspots located outside PAs was estimated as a measure of conservation gaps in Xishuangbanna. Our results revealed a long collecting history of ferns and lycophytes in Xishuangbanna and this prefecture accumulated a considerable number of historical records covering 20.2 % of Chinese and 3.6% of global fern diversity. The accumulation of historical records showed strong parallelism to the historical events shaping modern China. The spatial distribution of ferns and lycophytes in Xishuangbanna was characterized by a concentration of species richness in southern valleys and endemism in western and northern mountains. In terms of conservation, existing PAs showed higher effectiveness in the protection of species richness, whereas lower effectiveness was observed in the protection of endemism and beta diversity. Our research provided a key reference for understanding the diversity and conservation of ferns and lycophytes in Xishuangbanna, as well as highlighting the locality for future collecting and conservation efforts. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Acupuncture is a key part of traditional Chinese medicine, shown to induce favorable neuroplasticity for injuries in the central and peripheral nervous systems. Recent studies report elongated needle therapy (ENT) with BL54 and ST28 may restore acute spinal cord injury (ASCI). However, the precise mechanism for this has not been elucidated. Aim of the study In our current study, we investigated the effects of ENT on inflammation and neuronal apoptosis induced by ASCI, and whether PI3K/Akt and MAPK/ERK signaling pathways are involved in the ENT restoration effect. Materials and methods Rat models of moderate SCI were established in accordance with the modified Allen's method and were treated with ENT continuously for 7 days. Spontaneous activities were evaluated by the Basso Beattie and Bresnahan locomotor scale. Levels of inflammatory cytokines, such as tumor necrosis factor alpha, interleukin-6, IL-1β, and nuclear factor kappa-β, were determined by enzyme-linked immunosorbent assay. Cell apoptosis was examined by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The proportions of cells with positive Bcl-2 and Bax expression were determined by immunohistochemical assays, whilst the expression profiles of p-AKT and p-ERK in spinal cord tissues were evaluated by western blotting. Furthermore, the expression profiles of Cytochrome-C (Cyt-C) and caspase-3 in vivo were analyzed by reverse transcription polymerase chain reaction. The potential inhibitory effects downstream of the Akt and ERK signaling pathways were examined by administration of specific inhibitors LY294002 and PD98059 in vivo. Results As indicated by this study, inflammation as well as PI3K/Akt- and MAPK/ERK signaling pathway-mediated neuronal apoptosis were involved in the course of SCI in rats. The neuro-protective effect of ENT was associated with reduced Bax protein-positive neurons and increased Bcl-2 protein-positive neurons. ENT enhanced recovery of rat activities. Activation of p-Akt and p-ERK in the PI3K/Akt and MAPK/ERK signaling pathways, inhibited expression of the critical component Cyt-C. Cyt-C is required for the mitochondrial apoptosis pathway and cascade of caspase-3, which is involved in activation of neuronal apoptosis through down-regulation of Bax protein and up-regulation of Bcl-2, as determined by TUNEL. The administration of PI3K/Akt and MAPK/ERK signaling pathway specific inhibitors, LY294002 and PD98059, suppressed expression of both p-Akt and p-ERK. Conclusion ENT with BL54 and ST28 points can promote the recovery of ASCI. And the neuro-protective effect of ENT during the restoration of SCI may be associated with the suppression of both inflammation and activation of PI3K/Akt and MAPK/ERK signaling pathways, resulting from down-regulation of Bax protein, up-regulation of Bcl-2, and inhibition of the mitochondrial apoptosis pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • Driving factors and mechanisms underlying urbanization in DLB were clarified. • Three urbanization scenarios land uses maps of DLB in 2035 were simulated. • ESs in 2035 under three urbanization scenarios were evaluated and tradeoffed. • An optimized urbanization path and land use pattern were proposed. • Ecological Red Line, Ecological Isolation Strips, economic and intensive use of land should be targeted. Dianchi Lake Basin (DLB) is a typical and representative type of urbanization model based on the plateau lake ecosystem, with scarce land resources, deficient water resources, and a fragile ecological environment, in parallel with large-scale and rapid urbanization. To increase ecological security and maintain ecosystem services (ESs), it is essential to analyze the paths and processes for implementing sustainable urbanization. Using combined CLUE-S-Markov-InVEST modeling, the study simulated ESs changes and distribution in DLB under a natural increase scenario (NIS), an urban plan scenario (UPS), and an ecological protection scenario (EPS). EPS proved to be the best-optimized urbanization path and land use pattern that can meet land use demand for urbanization, but also maintain (or even improve) regional ESs levels. The major driving mechanisms underlying urbanization effects on ESs were found to be selection of urbanization path, scale control and layout of construction land, demarcation and implementation of ecological red line and ecological protection areas. The results indicate that DLB should follow the EPS urbanization path, an ecological red line should be reasonably delineated and observed, and ecological isolation strips should be established at appropriate locations. Additionally, the scale of construction land should be strictly controlled, constructed land should be used more intensively, and the utilization efficiency of construction land should be improved. [ABSTRACT FROM AUTHOR]