Understanding the impact of meteorological and topographical factors on snow cover fraction(SCF)is crucial for water resource management in the Qilian Mountains(QLM),China.However,there is still a lack of adequate qua...Understanding the impact of meteorological and topographical factors on snow cover fraction(SCF)is crucial for water resource management in the Qilian Mountains(QLM),China.However,there is still a lack of adequate quantitative analysis of the impact of these factors.This study investigated the spatiotemporal characteristics and trends of SCF in the QLM based on the cloud-removed Moderate Resolution Imaging Spectroradiometer(MODIS)SCF dataset during 2000-2021 and conducted a quantitative analysis of the drivers using a histogram-based gradient boosting regression tree(HGBRT)model.The results indicated that the monthly distribution of SCF exhibited a bimodal pattern.The SCF showed a pattern of higher values in the western regions and lower values in the eastern regions.Overall,the SCF showed a decreasing trend during 2000-2021.The decrease in SCF occurred at higher elevations,while an increase was observed at lower elevations.At the annual scale,the SCF showed a downward trend in the western regions affected by westerly(52.84%of the QLM).However,the opposite trend was observed in the eastern regions affected by monsoon(45.73%of the QLM).The SCF displayed broadly similar spatial patterns in autumn and winter,with a significant decrease in the western regions and a slight increase in the central and eastern regions.The effect of spring SCF on spring surface runoff was more pronounced than that of winter SCF.Furthermore,compared with meteorological factors,a variation of 46.53%in spring surface runoff can be attributed to changes in spring SCF.At the annual scale,temperature and relative humidity were the most important drivers of SCF change.An increase in temperature exceeding 0.04°C/a was observed to result in a decline in SCF,with a maximum decrease of 0.22%/a.An increase in relative humidity of more than 0.02%/a stabilized the rise in SCF(about 0.06%/a).The impacts of slope and aspect were found to be minimal.At the seasonal scale,the primary factors impacting SCF change varied.In spring,precipitation and wind speed emerged as the primary drivers.In autumn,precipitation and temperature were identified as the primary drivers.In winter,relative humidity and precipitation were the most important drivers.In contrast to the other seasons,slope exerted the strongest influence on SCF change in summer.This study facilitates a detailed quantitative description of SCF change in the QLM,enhancing the effectiveness of watershed water resource management and ecological conservation efforts in this region.展开更多
In order to explore the application of saussurea involucrata extract in skin care products,the skin care efficacy and safety of saussurea involucrata extract were verified through hyaluronidase inhibition test,zebrafi...In order to explore the application of saussurea involucrata extract in skin care products,the skin care efficacy and safety of saussurea involucrata extract were verified through hyaluronidase inhibition test,zebrafish repair efficacy evaluation,human immortalized epidermal cell anti-photodamage test,in vitro anti-glycation test,fibroblast proliferation test,zebrafish whitening test,human clinical trial and closed patch test.The results showed that 10%of the extract passed the closed patch test,indicating that it was mild and non-irritating.Saussurea involucrata extract can inhibit hyaluronidase activity and promote the production of blocking protein,indicating that it has soothing and repairing effect at the same time.The extract can significantly inhibit the glycosylation reaction,and can effectively resist the damage of blue light and ultraviolet,and has certain anti-glycosylation and antiphotodamage effects.The extract can promote the proliferation of 3T3 cells,and has certain firming and anti-wrinkle effect.The extract can effectively inhibit the melanin production of zebrafish and has certain whitening effect.The human clinical trial comparative test confirmed that the whitening effect of 10%saussurea involucrata extract is equivalent to 7%ascorbic acid.展开更多
Shear-sliding mode(mode Ⅱ)fracture of rocks is a vital failure form in deep underground engineering.To gain deep insight into the anisotropic shear fracture behaviors of a typical shale under high normal stress condi...Shear-sliding mode(mode Ⅱ)fracture of rocks is a vital failure form in deep underground engineering.To gain deep insight into the anisotropic shear fracture behaviors of a typical shale under high normal stress conditions,a series of direct shear tests were conducted on double-notched specimens in three typical bedding orientations(i.e.,the arrester,divider,short-transverse orientations)and under five normal stresses.The modeⅡfracture toughness(K_(Ⅱc))is found to exhibit a significant 3D anisotropy.The maximum K_(Ⅱc)is obtained in the divider orientation,followed by those in the arrester and short-transverse orientations.In contrast,the 3D anisotropy in the critical modeⅡenergy release rate(G_(Ⅱc))is not as significant as that in K_(Ⅱc),and G_(Ⅱc)in the arrester orientation is quite close to that in the divider orientation.The anisotropy in the prepeak input energy accumulated during shearing is found to be exactly consistent with that in G_(Ⅱc),which has not been noted before.Furthermore,the anisotropies in the modeⅡfracture resistances will,unexpectedly,not be weakened by the high normal stress.Owing to the layered structures,tensile cracks are involved during the modeⅡfracture process,resulting in the formation of rough fracture surfaces.展开更多
Phosphate transporters play an important role in promoting the uptake and transport of phosphate in plants. In this study, the McPht gene from the Mesembryanthemum crystallinum, a mitochondrial phosphate transporter, ...Phosphate transporters play an important role in promoting the uptake and transport of phosphate in plants. In this study, the McPht gene from the Mesembryanthemum crystallinum, a mitochondrial phosphate transporter, was isolated and constructed onto a constitutive expression vector carrying 35S：：GFP, and the recombinant constructs were transferred into Oryza sativajaponica L. cv. Kitaake to investigate the regulatory role of the McPhtgene under phosphorus deficiency. The McPhtgene encodes a protein of 357 amino acids with six transmembrane domains and is located to the mitochondria, and the mRNAtranscripts of the McPht gene are highly accumulated in the shoots of M. crystallinum in response to phosphorus deficiency. However, more mRNA transcripts of the McPht gene were accumulated in the roots of the transgenic rice under phosphorus deficiency. Measurements showed that the transgenic rice demonstrated an enhanced promotion in the root development, the root activities, and phosphate uptake under phosphorus deficiency. Transcriptome sequencing showed that the transgenic rice exhibited total of 198 differentially expressed genes. Of these, total of 154 differentially expressed genes were up-regulated and total 44 genes were down-regulated comparing to the wild type in response to phosphorus deficiency. The selective six genes of the up-regulated differentially expressed genes showed an enhanced increase in mRNA transcripts in response to phosphorus deficiency, however, the transcripts of the mitochondrial carrier protein transporter in rice, a homologous gene of the McPht, in both the transgenic line and the wild type had no obvious differences. Functional enrichment analyses revealed that the most of the up-regulated genes are involved in the cytoplasmic membrane-bounded vesicle, and most of the down-regulated genes are involved in the mitochondrion and cytoplasmic membrane-bounded vesicle. The differentially expressed genes were highly enriched in plant secondary metabolisms and plant-pathogen interaction. These results indicated that the overexpression of the McPht gene might participate in the physiological adaptive modulation of the transgenic rice to phosphorus deficiency by up- or down-regulating the differentially expressed genes.展开更多
Leaf color and photosynthesis are important factors for rice growth and development.Hence,improving the photosynthetic rate is an effective approach for increasing rice yield.We isolated a gene,chlorophyllide-a oxygen...Leaf color and photosynthesis are important factors for rice growth and development.Hence,improving the photosynthetic rate is an effective approach for increasing rice yield.We isolated a gene,chlorophyllide-a oxygenase 1(OsCAO1),which characterized a rice near-isogenic line named fgl(faded green leaf).展开更多
基金funded by the Key Research and Development Project for Ecological Civilization Construction in Gansu Province(24YFFA010)the Gansu Province Major Science and Technology Project(22ZD6FA005)+2 种基金the Natural Science Foundation of Gansu Province(24JRRA091)the Shanxi Province Basic Research Program(Free Exploration Category)Youth Project(202403021212316)the Science and Technology Innovation Program for Universities in Shanxi Province(2024L327)。
文摘Understanding the impact of meteorological and topographical factors on snow cover fraction(SCF)is crucial for water resource management in the Qilian Mountains(QLM),China.However,there is still a lack of adequate quantitative analysis of the impact of these factors.This study investigated the spatiotemporal characteristics and trends of SCF in the QLM based on the cloud-removed Moderate Resolution Imaging Spectroradiometer(MODIS)SCF dataset during 2000-2021 and conducted a quantitative analysis of the drivers using a histogram-based gradient boosting regression tree(HGBRT)model.The results indicated that the monthly distribution of SCF exhibited a bimodal pattern.The SCF showed a pattern of higher values in the western regions and lower values in the eastern regions.Overall,the SCF showed a decreasing trend during 2000-2021.The decrease in SCF occurred at higher elevations,while an increase was observed at lower elevations.At the annual scale,the SCF showed a downward trend in the western regions affected by westerly(52.84%of the QLM).However,the opposite trend was observed in the eastern regions affected by monsoon(45.73%of the QLM).The SCF displayed broadly similar spatial patterns in autumn and winter,with a significant decrease in the western regions and a slight increase in the central and eastern regions.The effect of spring SCF on spring surface runoff was more pronounced than that of winter SCF.Furthermore,compared with meteorological factors,a variation of 46.53%in spring surface runoff can be attributed to changes in spring SCF.At the annual scale,temperature and relative humidity were the most important drivers of SCF change.An increase in temperature exceeding 0.04°C/a was observed to result in a decline in SCF,with a maximum decrease of 0.22%/a.An increase in relative humidity of more than 0.02%/a stabilized the rise in SCF(about 0.06%/a).The impacts of slope and aspect were found to be minimal.At the seasonal scale,the primary factors impacting SCF change varied.In spring,precipitation and wind speed emerged as the primary drivers.In autumn,precipitation and temperature were identified as the primary drivers.In winter,relative humidity and precipitation were the most important drivers.In contrast to the other seasons,slope exerted the strongest influence on SCF change in summer.This study facilitates a detailed quantitative description of SCF change in the QLM,enhancing the effectiveness of watershed water resource management and ecological conservation efforts in this region.
文摘In order to explore the application of saussurea involucrata extract in skin care products,the skin care efficacy and safety of saussurea involucrata extract were verified through hyaluronidase inhibition test,zebrafish repair efficacy evaluation,human immortalized epidermal cell anti-photodamage test,in vitro anti-glycation test,fibroblast proliferation test,zebrafish whitening test,human clinical trial and closed patch test.The results showed that 10%of the extract passed the closed patch test,indicating that it was mild and non-irritating.Saussurea involucrata extract can inhibit hyaluronidase activity and promote the production of blocking protein,indicating that it has soothing and repairing effect at the same time.The extract can significantly inhibit the glycosylation reaction,and can effectively resist the damage of blue light and ultraviolet,and has certain anti-glycosylation and antiphotodamage effects.The extract can promote the proliferation of 3T3 cells,and has certain firming and anti-wrinkle effect.The extract can effectively inhibit the melanin production of zebrafish and has certain whitening effect.The human clinical trial comparative test confirmed that the whitening effect of 10%saussurea involucrata extract is equivalent to 7%ascorbic acid.
基金Project(12172240)supported by the National Natural Science Foundation of ChinaProject(2021YFH0030)supported by the Science&Technology Department of Sichuan Province,China。
文摘Shear-sliding mode(mode Ⅱ)fracture of rocks is a vital failure form in deep underground engineering.To gain deep insight into the anisotropic shear fracture behaviors of a typical shale under high normal stress conditions,a series of direct shear tests were conducted on double-notched specimens in three typical bedding orientations(i.e.,the arrester,divider,short-transverse orientations)and under five normal stresses.The modeⅡfracture toughness(K_(Ⅱc))is found to exhibit a significant 3D anisotropy.The maximum K_(Ⅱc)is obtained in the divider orientation,followed by those in the arrester and short-transverse orientations.In contrast,the 3D anisotropy in the critical modeⅡenergy release rate(G_(Ⅱc))is not as significant as that in K_(Ⅱc),and G_(Ⅱc)in the arrester orientation is quite close to that in the divider orientation.The anisotropy in the prepeak input energy accumulated during shearing is found to be exactly consistent with that in G_(Ⅱc),which has not been noted before.Furthermore,the anisotropies in the modeⅡfracture resistances will,unexpectedly,not be weakened by the high normal stress.Owing to the layered structures,tensile cracks are involved during the modeⅡfracture process,resulting in the formation of rough fracture surfaces.
基金supported by the National Key Project for Cultivation of New Varieties of Genetically Modified Organisms,Ministry of Agriculture,China (2016ZX08002005)the National Basic Research Program of China(2015CB150800)
文摘Phosphate transporters play an important role in promoting the uptake and transport of phosphate in plants. In this study, the McPht gene from the Mesembryanthemum crystallinum, a mitochondrial phosphate transporter, was isolated and constructed onto a constitutive expression vector carrying 35S：：GFP, and the recombinant constructs were transferred into Oryza sativajaponica L. cv. Kitaake to investigate the regulatory role of the McPhtgene under phosphorus deficiency. The McPhtgene encodes a protein of 357 amino acids with six transmembrane domains and is located to the mitochondria, and the mRNAtranscripts of the McPht gene are highly accumulated in the shoots of M. crystallinum in response to phosphorus deficiency. However, more mRNA transcripts of the McPht gene were accumulated in the roots of the transgenic rice under phosphorus deficiency. Measurements showed that the transgenic rice demonstrated an enhanced promotion in the root development, the root activities, and phosphate uptake under phosphorus deficiency. Transcriptome sequencing showed that the transgenic rice exhibited total of 198 differentially expressed genes. Of these, total of 154 differentially expressed genes were up-regulated and total 44 genes were down-regulated comparing to the wild type in response to phosphorus deficiency. The selective six genes of the up-regulated differentially expressed genes showed an enhanced increase in mRNA transcripts in response to phosphorus deficiency, however, the transcripts of the mitochondrial carrier protein transporter in rice, a homologous gene of the McPht, in both the transgenic line and the wild type had no obvious differences. Functional enrichment analyses revealed that the most of the up-regulated genes are involved in the cytoplasmic membrane-bounded vesicle, and most of the down-regulated genes are involved in the mitochondrion and cytoplasmic membrane-bounded vesicle. The differentially expressed genes were highly enriched in plant secondary metabolisms and plant-pathogen interaction. These results indicated that the overexpression of the McPht gene might participate in the physiological adaptive modulation of the transgenic rice to phosphorus deficiency by up- or down-regulating the differentially expressed genes.
基金supported by the Shenzhen Science and Technology Program,China(Grant No.KQTD2016113010482651)Natural Science Foundation of Zhejiang Province in China(Grant No.LR20C130001)Hainan Yazhou Bay Seed Laboratory,China(Grant No.B21HJ0219)。
文摘Leaf color and photosynthesis are important factors for rice growth and development.Hence,improving the photosynthetic rate is an effective approach for increasing rice yield.We isolated a gene,chlorophyllide-a oxygenase 1(OsCAO1),which characterized a rice near-isogenic line named fgl(faded green leaf).
