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As an important part of ecological hydrology, transpiration is the basis for analyzing forest water cycle and healthy growth, and important for forest protection and scientific management. We used thermal diffusion probes (TDP) to continuously monitor sap flow of Picea crassifolia in the Qilian Mountains from 2017 to 2018 to explore water consumption of P. crassifolia, and analyze the main controlling factors for the growth and transpiration of spruce. The results showed that the instantaneous change of P. crassifolia sap flow showed a single-peak curve in sunny days, a multi-peak or double-peak curve in cloudy days, and basically no obvious regularity in rainy days. The sap flow density of Qinghai spruce was consistent with the dynamics of solar radiation. The sap flow started earlier and ended later on sunny days, and lasted for 12 to 14 hours. Due to the high altitude (2700 m), low air temperature, and low vapor pressure difference (VPD) in this area, the overall sap flow density was low, with an average of (0.86±0.49) kg · d-1. On the hourly scale, the instantaneous rate of sap flow was significantly affected by solar radiation and VPD. On the daily scale, soil temperature and soil moisture content of the 0-40 cm layer were significantly related to sap flow density. The spruce sap flow density decreased with the decreases of solar radi-ation, air temperature, and VPD. In the high-altitude forest area of Qilian Mountains, lower soil and air temperature as well as lower VPD and solar radiation were the causes of low sap flow in Picea crassifolia in this area. [ABSTRACT FROM AUTHOR]

Grasslands in Qilian Mountains plays an important role in maintaining the ecological security of western China. To understand soil physical and chemical properties and the distribution characteristics of vegetation, as well as their correlation in different types of grasslands in Qilian Mountains, we measured soil moisture, nutrient content, bulk density, particle composition, and vegetation characteristics in seven types of grassland in Qilian Mountains. The fractal dimension of soil particles, soil organic carbon, total nitrogen and total phosphorus storages in 0-40 cm soil layer, and plant diversity index were calculated. The results showed that there were significant differences in soil physical and chemical properties and vegetation characteristics among different grassland types. Compared with other types of grassland, alpine meadow had higher soil water, nutrient and clay content, but lower bulk density and sand content. Soil organic carbon, total nitrogen and total phosphorus storages in 0-40 cm layer ranged from 3084 to 45247, 164 to 2358 and 100 to 319 g· m-2, respectively, with high contents of organic carbon and total nitrogen and low content of total phosphorus. There was a significant positive correlation between soil total phosphorus storage and plant diversity index, indicating that soil total phosphorus content was the key factor affecting grassland plant diversity in Qilian Mountains. Compared with other grassland types, alpine meadow in Qilian Mountains had better vegetation status, soil moisture, and nutrient conditions. [ABSTRACT FROM AUTHOR]

As an important part of ecological hydrology, transpiration is the basis for analyzing forest water cycle and healthy growth, and important for forest protection and scientific management. We used thermal diffusion probes (TDP) to continuously monitor sap flow of Picea crassifolia in the Qilian Mountains from 2017 to 2018 to explore water consumption of P. crassifolia , and analyze the main controlling factors for the growth and transpiration of spruce. The results showed that the instantaneous change of P. crassifolia sap flow showed a single-peak curve in sunny days, a multi-peak or double-peak curve in cloudy days, and basically no obvious regularity in rainy days. The sap flow density of Qinghai spruce was consistent with the dynamics of solar radiation. The sap flow started earlier and ended later on sunny days, and lasted for 12 to 14 hours. Due to the high altitude (2700 m), low air temperature, and low vapor pressure difference (VPD) in this area, the overall sap flow density was low, with an average of (0.86±0.49) kg·d -1 . On the hourly scale, the instantaneous rate of sap flow was significantly affected by solar radiation and VPD. On the daily scale, soil temperature and soil moisture content of the 0-40 cm layer were significantly related to sap flow density. The spruce sap flow density decreased with the decreases of solar radiation, air temperature, and VPD. In the high-altitude forest area of Qilian Mountains, lower soil and air temperature as well as lower VPD and solar radiation were the causes of low sap flow in Picea crassifolia in this area.

Grasslands in Qilian Mountains plays an important role in maintaining the ecological security of western China. To understand soil physical and chemical properties and the distribution characteristics of vegetation, as well as their correlation in different types of grasslands in Qilian Mountains, we measured soil moisture, nutrient content, bulk density, particle composition, and vegetation characteristics in seven types of grassland in Qilian Mountains. The fractal dimension of soil particles, soil organic carbon, total nitrogen and total phosphorus storages in 0-40 cm soil layer, and plant diversity index were calculated. The results showed that there were significant differences in soil physical and chemical properties and vegetation characteristics among different grassland types. Compared with other types of grassland, alpine meadow had higher soil water, nutrient and clay content, but lower bulk density and sand content. Soil organic carbon, total nitrogen and total phosphorus storages in 0-40 cm layer ranged from 3084 to 45247, 164 to 2358 and 100 to 319 g·m -2 , respectively, with high contents of organic carbon and total nitrogen and low content of total phosphorus. There was a significant positive correlation between soil total phosphorus storage and plant diversity index, indicating that soil total phosphorus content was the key factor affec-ting grassland plant diversity in Qilian Mountains. Compared with other grassland types, alpine meadow in Qilian Mountains had better vegetation status, soil moisture, and nutrient conditions.

Background: Numerous studies have indicated that the neddylation pathway is closely associated with tumor development. MLN4924 (Pevonedistat), an inhibitor of the NEDD8-activating E1 enzyme, is considered a promising chemotherapeutic agent. Recently, we demonstrated that neddylation of the tumor suppressor PTEN occurs under high glucose conditions and promotes breast cancer development. It has been shown, however, that PTEN protein levels are reduced by 30-40% in breast cancer. Whether this PTEN deficiency affects the anti-tumor function of MLN4924 is unknown. Methods: In the present study, cell counting kit-8 and colony formation assays were used to detect cell proliferation, and a transwell system was used to quantify cell migration. A tumor growth assay was performed in BALB/c nude mice. The subcellular location of PTEN was detected by fluorescence microscopy. The CpG island of the UBA3 gene was predicted by the Database of CpG Islands and UCSC database. Western blotting and qRT-PCR were used to measure the expression of indicated proteins. The Human Protein Atlas database, the Cancer Genome Atlas and Gene Expression Omnibus datasets were used to validate the expression levels of UBA3 in breast cancer. Results: Our data show that the anti-tumor efficacy of MLN4924 in breast cancer cells was markedly reduced with the deletion of PTEN. PI3K/Akt signaling pathway activity correlated positively with UBA3 expression. Pathway activity correlated negatively with NEDP1 expression in PTEN-positive breast cancer patients, but not in PTEN-negative patients. We also demonstrate that high glucose conditions upregulate UBA3 mRNA by inhibiting UBA3 promoter methylation, and this upregulation results in the overactivation of PTEN neddylation in breast cancer cells. Conclusion: These data suggest a mechanism by which high glucose activates neddylation. PTEN is critical, if not indispensable, for MLN4924 suppression of tumor growth; PTEN status thus may help to identify MLN4924-responsive breast cancer patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Du, Peng, Gai, Liu, Liu, Chen, Li, Zhang, Liu, Zhang, Jiang and Xie.)