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Early stages of post-fire regeneration are sensitive to various factors, and can provide critical information for understanding forest responses to fire disturbance and projecting subsequent forest dynamics. Yunnan pine forests are the most widespread conifer forest type in Southwest China, and are frequently threatened by fire disturbance. Post-fire regeneration of this forest type, however, has not been previously studied. In this study, we investigated the early post-fire regeneration in mixed Yunnan pine forests five months after a severe burn in 2013 on Mt. Qinglongling, Yunnan Province, China. We found very active post-fire regeneration in the burned area likely facilitated by ample summer rainfall, with an average regeneration density of ∼10 5 stems ha −1 . Species composition of the post-fire regeneration was highly similar to the pre-fire community–the similarity between the pre- and post-fire communities was 0.530 ± 0.222. Elevation, pre-fire community type, and slope position were the three primary factors in the variations in regeneration density and species composition, while the impact of fire severity was low. The regeneration density of Pinus species and evergreen broadleaf species showed contrasting patterns across the environmental gradients, and the results implied that Yunnan forests are generally resilient to fire disturbance. The controlling impacts of the pre-fire community on post-fire regeneration are driven by the efficient regenerating strategies of dominant species, and are a comprehensive reflection of habitat conditions, which are primarily mediated by topographic features. Species regeneration strategies and the high resilience of the community to fire disturbance should be taken into account in fire prevention and management approaches for this forest type. [ABSTRACT FROM AUTHOR]

• We compared vegetation phenology from a SIF product (CSIF) and from MODIS NDVI. • We found similar spatial patterns in CSIF and NDVI derived phenology. • NDVI data indicated an earlier start and later end of the growing season than CSIF. • Models based on leaf greenness may overestimate photosynthesis active period. Vegetation phenology is highly sensitive to climate change, although the data and methods used to estimate key phenological states can influence this sensitivity. Because of its direct relation to leaf photosynthetic carbon uptake, remotely sensed solar-induced chlorophyll fluorescence (SIF) can provide new insight assessing changes in vegetation phenology. Here, we investigated the potential of using a SIF time series product named contiguous SIF (CSIF) to estimate spring, summer, and autumn phenology in the extratropical Northern Hemisphere (>30°N) and compared the results with those based on Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) for the period 2001–2018. Overall, we found similar spatial patterns in phenological states. However, specific dates of key phenological events differed when using CSIF vs. MODIS NDVI data. NDVI data indicated that the growing season started earlier (by 10.1 days on average) and ended later (11.5 days on average) relative to CSIF data. This implies that actual periods for photosynthetic activity are shorter (by 21.6 days on average) than those estimated from vegetation indices more directly related to changes in canopy structure. These large differences between results from NDVI and that from CSIF suggest that vegetation indices such as NDVI seem to overestimate the period for active photosynthesis over the extratropical Northern Hemisphere. Furthermore, while phenology of the early growing season is dominated by temperature for both NDVI and CSIF data, phenology of the late growing season is mainly controlled by temperature for NDVI but by precipitation for CSIF. Our findings were further confirmed by other SIF (GOME-2 SIF) and vegetation index (MODIS EVI) datasets. Phenology modes in Earth system modelling are often parameterized using leaf unfolding and senescence from either station or satellite observations. Our results imply that canopy structure-based parameterization schemes may have overestimated photosynthesis active period, and thus productivity responses. We conclude that SIF data offers a novel and unique approach for assessing phenological change - one that is more directly tied to the carbon cycle and how it is being influenced by climate change. [ABSTRACT FROM AUTHOR]

Abstract: Diabetes is featured by elevated levels of blood glucose, i.e. hyperglycemia, which might be a risk factor for hepatic fibrogenesis in patients with non-alcoholic steatohepatitis. Hepatic stellate cells (HSCs) are the major effectors during hepatic fibrogenesis. This study was designed to evaluate impacts of high levels of glucose on HSC activation, assess roles of the phytochemical curcumin in attenuating the glucose impacts, and elucidate underlying mechanisms. In this report, levels of intracellular glucose were measured. Contents and gene expression of glucose transporter-2 (GLUT2) in cell fractions were examined. Levels of cellular glutathione and oxidative stress were analyzed. We observed that high levels of glucose induced cell proliferation, type I collagen production and expression of genes relevant to HSC activation, and elevated intracellular glucose levels in cultured HSCs. Curcumin eliminated the stimulatory impacts. Curcumin abrogated the membrane translocation of GLUT2 by interrupting the p38 MAPK signaling pathway. In addition, curcumin suppressed glut2 expression by stimulating the activity of peroxisome proliferator-activated receptor-gamma (PPARγ) and de novo synthesis of glutathione. In conclusion, hyperglycemia stimulated HSC activation in vitro by increasing intracellular glucose, which was eliminated by curcumin by blocking the membrane translocation of GLUT2 and suppressing glut2 expression. The latter was mediated by activating PPARγ and attenuating oxidative stress. Our results presented evidence to impacts of hyperglycemia on stimulating HSC activation and hepatic fibrogenesis, and provided novel insights into the mechanisms by which curcumin eliminated the hyperglycemia-caused HSC activation and potential therapeutic strategies for treatment of diabetes-associated hepatic fibrogenesis. [Copyright &y& Elsevier]

Abstract: This paper investigates almost automorphic mild solutions of the fractional semilinear equation , considered in a Banach space , where is a linear operator of sectorial type . Some sufficient conditions are given for the existence, uniqueness and uniform stability of almost automorphic mild solutions to this semilinear equation. [Copyright &y& Elsevier]

Abstract: Some sufficient conditions are obtained for the global exponential stability of periodic solutions to periodic bi-directional Cohen–Grossberg neural networks involving distributed delays, by using the Lyapunov functional method and some analytical techniques. These results improve and generalize some previous works, and are helpful for designing a global exponential stable periodic bi-directional Cohen–Grossberg neural networks. [Copyright &y& Elsevier]

Abstract: Hepatic stellate cells (HSC) are the major effectors in hepatic fibrogenesis. During liver injury, HSC become activated and proliferative. Platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) are the potent mitogens for many cell types. We previously demonstrated that (−)-epigallocatechin gallate (EGCG), the major and active component in green tea extracts, inhibited HSC growth, including reducing cell proliferation, and inducing apoptosis. We have reported that EGCG interrupts PDGF signaling by reducing receptor tyrosine phosphorylation and gene expression of PDGF-β receptor. Additional experiments are necessary to elucidate the effect of EGCG on EGF signaling in activated HSC. The aims of this study are to evaluate the effect of EGCG on the expression of EGFR and to elucidate the underlying molecular mechanisms in activated HSC. We hypothesize that EGCG might interrupt EGF signaling by suppressing gene expression of EGF receptor (EGFR) in activated HSC, which, together with the interruption of PDGF signaling, might collectively result in the inhibition of HSC growth. The present report demonstrates that the phyto-chemical dose-dependently suppresses gene expression of EGFR in activated HSC in vitro. The Egr-1 binding site located in the egfr promoter is found to be cis-activating element in regulating the promoter activity of the gene. EGCG inhibits the trans-activation activity of Egr-1 in activated HSC by suppressing gene expression of the transcription factor. The interruption of the ERK signaling pathway by EGCG reduces the trans-activation activity of Egr-1 and the promoter activity of EGFR gene in HSC. Taken together, our results demonstrate that EGCG suppresses gene expression of EGFR in rat activated HSC in vitro mediated by reducing the trans-activation activity of Egr-1. [Copyright &y& Elsevier]

Abstract: By using the continuation theorem of coincidence degree theory and Liapunov function, we obtain some sufficient criteria to ensure the existence and global exponential stability of periodic solution to the bidirectional associative memory (BAM) neural networks with periodic coefficients and continuously distributed delays. These results improve and generalize the works of papers [J. Cao, L. Wang, Phys. Rev. E 61 (2000) 1825] and [Z. Liu, A. Chen, J. Cao, L. Huang, IEEE Trans. Circuits Systems I 50 (2003) 1162]. An example is given to illustrate that the criteria are feasible. [Copyright &y& Elsevier]

Abstract: In this Letter, several sufficient conditions are obtained for the almost periodic attractor of delayed neural networks with variable coefficients based on the theory of exponential dichotomy, Lyapunov method and Halanay inequality technique. Many previous results reported in the literature are extended or improved for neural networks with or without delays. The obtained results are helpful to design globally stable almost periodic oscillatory neural networks. A numerical example is also given in the end to show the feasibility of our results. [Copyright &y& Elsevier]

By using the Banach fixed point theorem and constructing suitable Lyapunov function, some sufficient conditions are obtained ensuring existence, uniqueness and global stability of almost periodic solution of the BAM neural networks with variable coefficients and delays. These results are helpful to design global exponential stable BAM networks and almost periodic oscillatory BAM networks. [Copyright &y& Elsevier]

By combining the theory of the exponential dichotomy and Liapunov function, we study the existence and attractivity of almost periodic solutions for cellular neural networks (CNNs) with distributed delays and variable coefficientsdxi/dt=−bi(t)xi(t)+∑j=1naij(t)fj(xj(t))+∑j=1nbij(t)fjμj∫0∞kij(u)xj(t−u) du+Ii(t).We obtain some sufficient conditions to ensure that for the networks there exists a unique almost periodic solution, and all its solutions converge to such an almost periodic solution. An example is given to illustrate that the conditions of our results are feasible. [Copyright &y& Elsevier]

Using the Banach fixed point theorem, we obtain a sufficient condition for the existence of almost periodic solution of shunting inhibitory cellular neural networks dxij/dt=−aijxij−∑lower limit Ckl∈Nr(i,j) Cijklfxkl(t−τ)xij+Lij(t), the global attractivity of SICNNs is also obtained. An example is given to illustrate that the condition of our results are feasible. [Copyright &y& Elsevier]

Adipogenesis is one of the triggers of obesity, which is a risk factor for various metabolic diseases. Long noncoding RNA steroid receptor RNA activator (lncRNA-SRA) is closely related to adipogenesis and p38/JNK mitogen-activated protein kinase mediates lipid production by regulating peroxisome proliferator-activated receptor gamma (PPARγ). Aerobic exercise can be efficient in improving adiposity and losing weight. Hence, we hypothesize that aerobic exercise ameliorates obesity by affecting the SRA/p38/JNK/PPARγ pathway and downstream target genes. The broad approaches used to test hypotheses are as follows. Spectrophotometer detected C57BL/6J mice blood lipid level; hematoxylin and eosin-stained fat tissue to check the grade of epididymis fat; quantitative polymerase chain reaction and Western blot detected messenger RNA expression and protein levels. Injected lncRNA-SRA virus vector to overexpress SRA. After 8 weeks of aerobic exercise intervention, obese mice showed significant improvements in body weight, white fat weight, lipid levels, and the Lee index. Aerobic exercise significantly inhibited the expression of SRA, activated the p38/JNK signaling pathway, further inhibited the expression of PPARγ and downstream target genes, and improved obesity. Aerobic exercise intervention improved lipid metabolism in obese mice, and the mechanism may be related to the regulation of the LncSRA/p38/JNK/PPARγ signaling pathway. Aerobic exercise is a globally recognized method for weight loss, and aerobic exercise successfully attenuates obesity by suppressing long noncoding steroid receptor RNA activator (lncSRA) expression caused by a high-fat diet. When lncSRA is suppressed, it activates the p38/JNK signaling pathway and further suppresses peroxisome proliferator-activated receptor gamma (PPARγ) and its downstream target genes, such as adipocyte fatty acid-binding protein-2, fatty acid synthase, phosphoenolpyruvate carboxykinase, and glucokinase. Hence, aerobic exercise inhibits lncSRA expression and further activates p38/JNK signaling pathway to suppress PPARγ and its targets expression to improve adipogenesis. [Display omitted] [ABSTRACT FROM AUTHOR]