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•Ecological sources were identified by the importance of ES.•The comprehensive resistance was identified by the ecological sensitivity.•The MCR model was used to obtain the Ecological ...corridors.•An urgent need exists to construct the ESP at urban agglomeration scale.
Ecological security patterns are employed to characterize the health and integrity of an ecosystem. It is essential to achieve sustainable and high-quality development of cities and urban agglomerations and to enhance human well-being. Considering the Guanzhong Plain urban agglomeration as an example, this paper proposes a technical framework for the delineation of ecological security patterns at the urban agglomeration scale with the objective of protecting and restoring mountains-rivers-forests-farmlands-lakes-grasslands. The ecological sources were indicated by the importance-sensitivity ecological assessment method. Ecological corridors were identified by a minimum resistance model, and the ecological security pattern was derived. Twenty-three important ecological source sites were identified within the urban agglomeration, mainly located in the southern part of the Guanzhong Plain urban agglomeration, with an area of 9122.36 km2, accounting for 8.52% of the study area. The ecological sensitivity of the mountainous areas was relatively high, with ecological corridors showing a denser distribution in the south. The results of the study suggest that green infrastructure in the northern region should be strengthened, that the ecological functions of ecologically sensitive areas should be protected and enhanced, and that the connectivity of ecological corridors should be strengthened. The results provide guidance for the optimization of regional ecological security patterns for and the joint prevention and control of environmental pollution in the Guanzhong Plain.
The impact of climate change on thermal climate zones and building energy standards in China were investigated based on the latest weather data. The moving t-test method was applied to determine the ...jump phenomena of climate. Building simulation technique was used to quantitatively analyze the potential impact of re-assignment of cities to new thermal climate zones based on public building energy consumption. Cities were reassigned based on the meteorological data recorded after 1997 investigated to be more rational representing current climate conditions. Among 354 cities investigated, 30 cities were reassigned to warmer climate zones; however, 8 cities cannot be assigned to any zone. Moreover, simulation results indicated that better building energy conservation would be achieved if office buildings located in those cities were designed according to building allowances regulated in the standard corresponding to the reassigned climate zone. The defects of current climate zones were identified and new updated zones were defined. Compared with current climate zones, the total area of severe-cold-zone (SCZ) in the new updated one has decreased significantly, while the area of cold-zone (CZ) has increased. Boundary between SCZ and CZ has moved slightly towards north, while boundary between CZ and hot-summer-and-cold-winter zone has moved farther north.
•Moving t-test method detected the variation in the climate condition in China.•Defects of current thermal climate zones in China were observed.•Updated zones were defined by revised criteria and rational period of climate data.
Mitochondria undergo dynamic fusion/fission, biogenesis and mitophagy in response to stimuli or stresses. Disruption of mitochondrial homeostasis could lead to cell senescence, although the ...underlying mechanism remains unclear. We show that deletion of mitochondrial phosphatase PGAM5 leads to accelerated retinal pigment epithelial (RPE) senescence in vitro and in vivo. Mechanistically, PGAM5 is required for mitochondrial fission through dephosphorylating DRP1. PGAM5 deletion leads to increased mitochondrial fusion and decreased mitochondrial turnover. As results, cellular ATP and reactive oxygen species (ROS) levels are elevated, mTOR and IRF/IFN-β signaling pathways are enhanced, leading to cellular senescence. Overexpression of Drp1 K38A or S637A mutant phenocopies or rescues mTOR activation and senescence in PGAM5
cells, respectively. Young but not aging Pgam5
mice are resistant to sodium iodate-induced RPE cell death. Our studies establish a link between defective mitochondrial fission, cellular senescence and age-dependent oxidative stress response, which have implications in age-related diseases.
Spindle assembly required during mitosis depends on microtubule polymerization. We demonstrate that the evolutionarily conserved low-complexity protein, BuGZ, undergoes phase transition or ...coacervation to promote assembly of both spindles and their associated components. BuGZ forms temperature-dependent liquid droplets alone or on microtubules in physiological buffers. Coacervation in vitro or in spindle and spindle matrix depends on hydrophobic residues in BuGZ. BuGZ coacervation and its binding to microtubules and tubulin are required to promote assembly of spindle and spindle matrix in Xenopus egg extract and in mammalian cells. Since several previously identified spindle-associated components also contain low-complexity regions, we propose that coacervating proteins may be a hallmark of proteins that comprise a spindle matrix that functions to promote assembly of spindles by concentrating its building blocks.
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•The spindle regulator BuGZ undergoes temperature-dependent phase transition•Phase transition of BuGZ relies on the aromatic and hydrophobic Phe and Tyr•BuGZ droplets promote microtubule polymerization•Phase transition of BuGZ promotes assembly of spindle and its matrix
A protein associated with the mitotic spindle must undergo a phase transition to promote microtubule polymerization and spindle assembly, suggesting that the biophysical properties associated with liquid demixing may shape the characteristics of a hypothesized but elusive spindle matrix.
Age-related macular degeneration (AMD) is a major cause of irreversible blindness among the elderly population. Dysfunction and degeneration of the retinal pigment epithelial (RPE) layer in the ...retina underscore the pathogenesis of both dry and wet AMD. Advanced age, cigarette smoke and genetic factors have been found to be the prominent risk factors for AMD, which point to an important role for oxidative stress and aging in AMD pathogenesis. However, the mechanisms whereby oxidative stress and aging lead to RPE cell degeneration are still unclear. As cell senescence and cell death are the major outcomes from oxidative stress and aging, here we review the mechanisms of RPE cell senescence and different kinds of cell death, including apoptosis, necroptosis, pyroptosis, ferroptosis, with an aim to clarify how RPE cell degeneration could occur in response to AMD-related stresses, including H
O
, 4-Hydroxynonenal (4-HNE), N-retinylidene-N-retinyl-ethanolamine (A2E), Alu RNA and amyloid β (Aβ). Besides those, sodium iodate (NaIO
) induced RPE cell degeneration is also discussed in this review. Although NaIO
itself is not related to AMD, this line of study would help understand the mechanism of RPE degeneration.
Coprinus comatus is a kind of fungus, which reveal the degradation of lignocellulose. In the present study, the strain was optimum cultivated and lignin degradation in corn stalk was investigated. ...The changes of corn stalk were characterized by scanning electron microscopy (SEM), specific surface area measurement (BET), X-ray diffraction (XRD), Fourier infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS). The results showed that the strain got its degradation of lignin up to 38.66 %. The strain eroded structure of corn stalk and formed pores, which accelerated the degradation of lignin. Treated by Coprinus comatus increased the specific surface area and reduced the crystallinity of corn stalk. Meanwhile, small molecular substances found in the treated corn stalk matrix. These demonstrated the effectives of Coprinus comatus for corn stalk degradation. The potentials of Coprinus comatus in this field need further investigation.
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•Coprinus comatus was identified.•Culture conditions for Coprinus comatus to degrade corn stalk were optimized by orthogonal experiments.•Enzyme activities of Coprinus comatus for lignocellulosic were assessed.•Degradation activities of Coprinus comatus for lignin, cellulose and hemicellulose of were determined.
Atherosclerosis, a hyperlipidemia-induced chronic inflammatory process of the arterial wall, develops preferentially at sites where disturbed laminar flow compromises endothelial cell (EC) function. ...Here we show that endothelial miR-126-5p maintains a proliferative reserve in ECs through suppression of the Notch1 inhibitor delta-like 1 homolog (Dlk1) and thereby prevents atherosclerotic lesion formation. Endothelial recovery after denudation was impaired in Mir126(-/-) mice because lack of miR-126-5p, but not miR-126-3p, reduced EC proliferation by derepressing Dlk1. At nonpredilection sites, high miR-126-5p levels in endothelial cells confer a proliferative reserve that compensates for the antiproliferative effects of hyperlipidemia, such that atherosclerosis was exacerbated in Mir126(-/-) mice. In contrast, downregulation of miR-126-5p by disturbed flow abrogated EC proliferation at predilection sites in response to hyperlipidemic stress through upregulation of Dlk1 expression. Administration of miR-126-5p rescued EC proliferation at predilection sites and limited atherosclerosis, introducing a potential therapeutic approach.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
MicroRNAs (miRNAs) modulate complex physiological and pathological processes by repressing expression of multiple components of cellular regulatory networks. Here we demonstrate that miRNAs encoded ...by the miR-23∼27∼24 gene clusters are enriched in endothelial cells and highly vascularized tissues. Inhibition of miR-23 and miR-27 function by locked nucleic acid-modified anti-miRNAs represses angiogenesis in vitro and postnatal retinal vascular development in vivo. Moreover, miR-23 and miR-27 are required for pathological angiogenesis in a laser-induced choroidal neovascularization mouse model. MiR-23 and miR-27 enhance angiogenesis by promoting angiogenic signaling through targeting Sprouty2 and Sema6A proteins, which exert antiangiogenic activity. Manipulating miR-23/27 levels may have important therapeutic implications in neovascular age-related macular degeneration and other vascular disorders.
This study used a structural equation modeling approach to investigate the relationships among L2 writing anxiety, L2 writing self-efficacy, L2 writing self-regulated strategies and L2 writing ...engagement, and possible mediators that regulate the effect of individual factors. A questionnaire was administered to 340 Chinese high school students from different parts of the country. The results of the study suggested a negative relationship between L2 writing anxiety and L2 writing self-efficacy, and a direct effect of both on L2 writing engagement. While a higher level of L2 writing self-efficacy indicated a lower level of L2 writing anxiety and more students' L2 writing engagement, L2 writing efficacy had a much stronger direct effect on L2 writing engagement than L2 writing anxiety. In addition, L2 writing self-regulated strategies were found to play a mediating role between L2 writing self-efficacy and L2 writing engagement, but not between L2 writing anxiety and L2 writing engagement. This study helps to understand the interplay of individual factors related to L2 writing and sheds light on promoting English writing abilities of Chinese high school students.
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