CDOM absorption properties of natural water bodies along extreme environmental gradients

We present absorption properties of colored dissolved organic matter (CDOM) sampled in six different water bodies along extreme altitudinal, latitudinal, and trophic state gradients. Three sites are in Norway: the mesotrophic Lysefjord (LF), Samnangerfjord (SF), and Røst Coastal Water (RCW); two sites are in China: the oligotrophic Lake Namtso (LN) and the eutrophic Bohai Sea (BS); and one site is in Uganda: the eutrophic Lake Victoria (LV). The site locations ranged from equatorial to subarctic regions, and they included water types from oligotrophic to eutrophic and altitudes from 0 m to 4700 m. The mean CDOM absorption coefficients at 440 nm [ a CDOM (440) aCDOM(440) ] and 320 nm [ a CDOM (320) aCDOM(320) ] varied in the ranges 0.063–0.35 m −1 −1 and 0.34–2.28 m −1 −1 , respectively, with highest values in LV, Uganda and the lowest in the high-altitude LN, Tibet. The mean spectral slopes S 280−500 S280−500 and S 350−500 S350−500 were found to vary in the ranges of 0.017–0.032 nm −1 −1 and 0.013–0.015 nm −1 −1 , respectively. The highest mean value for S 280−500 S280−500 as well as the lowest mean value for S 350−500 S350−500 were found in LN. Scatter plots of S 280−500 S280−500 versus a CDOM (440) aCDOM(440) and a CDOM (320) aCDOM(320) values ranges revealed a close connection between RCW, LF, and SF on one side, and BS and LV on the other side. CDOM seems to originate from terrestrial sources in LF, SF, BS, and LV, while RCW is characterized by autochthonous-oceanic CDOM, and LN by autochthonous CDOM. Photobleaching of CDOM is prominent in LN, demonstrated by absorption towards lower wavelengths in the UV spectrum. We conclude that high altitudes, implying high levels of UV radiation and oligotrophic water conditions are most important for making a significant change in CDOM absorption properties.publishedVersio

CDOM Absorption Properties of Natural Water Bodies along Extreme Environmental Gradients

We present absorption properties of colored dissolved organic matter (CDOM) sampled in six different water bodies along extreme altitudinal, latitudinal, and trophic state gradients. Three sites are in Norway: the mesotrophic Lysefjord (LF), Samnangerfjord (SF), and Røst Coastal Water (RCW); two sites are in China: the oligotrophic Lake Namtso (LN) and the eutrophic Bohai Sea (BS); and one site is in Uganda: the eutrophic Lake Victoria (LV). The site locations ranged from equatorial to subarctic regions, and they included water types from oligotrophic to eutrophic and altitudes from 0 m to 4700 m. The mean CDOM absorption coefficients at 440 nm [ a CDOM ( 440 ) ] and 320 nm [ a CDOM ( 320 ) ] varied in the ranges 0.063–0.35 m − 1 and 0.34–2.28 m − 1 , respectively, with highest values in LV, Uganda and the lowest in the high-altitude LN, Tibet. The mean spectral slopes S 280 − 500 and S 350 − 500 were found to vary in the ranges of 0.017–0.032 nm − 1 and 0.013–0.015 nm − 1 , respectively. The highest mean value for S 280 − 500 as well as the lowest mean value for S 350 − 500 were found in LN. Scatter plots of S 280 − 500 versus a CDOM ( 440 ) and a CDOM ( 320 ) values ranges revealed a close connection between RCW, LF, and SF on one side, and BS and LV on the other side. CDOM seems to originate from terrestrial sources in LF, SF, BS, and LV, while RCW is characterized by autochthonous-oceanic CDOM, and LN by autochthonous CDOM. Photobleaching of CDOM is prominent in LN, demonstrated by absorption towards lower wavelengths in the UV spectrum. We conclude that high altitudes, implying high levels of UV radiation and oligotrophic water conditions are most important for making a significant change in CDOM absorption properties

Characterization of the complete plastid genome of of Veronica eriogyne H. Winkl., a Tibetan medicinal herb

Veronica eriogyne H. Winkl.(Plantaginaceae) is a perennial herb with high medicinal value. To better understand the molecular genetics and evolutionary of V. eriogyne, its complete plastid genome was sequenced and annotated. The assembled chloroplast genome is a circular 151,083 bp sequence, consisting of a 82,302 bp large single copy region (LSC) and a 17,449 bp small single copy region (SSC), which were flanked by a pair of 25,666 bp inverted repeats (IRs). The GC content of the chloroplast genome is 38.03%. Moreover, a total of 134 functional genes were annotated, including 88 protein-coding, 38 tRNA, and 8 rRNA genes. Phylogenetic analysis showed that V. eriogyne has close relationship with V. persica Poi. The current study provides important information for further genetic studies on Plantaginacea

Complete mitochondrial genomes reveal the phylogenetic relationships of Duoma with eight representative sheep breeds and two ovis species

The Ovis aries Duoma breed is one of the most important alpine grassland-type sheep breeds in China. In this current study, we first reported the complete mitochondrial genome of Duoma sheep. Mitochondrial genome is 16,618 bp in length and exhibits the same typical structure as the other published sheep breeds. The genome contains 37 genes (22 tRNA, two rRNA, and 13 protein-coding genes (PCGs)) and a control region (D-loop region). Phylogenetic analysis shows that the Duoma sheep breed is closer to Ganjia sheep. Our findings will help the further evolution and conservation studies of Duoma sheep

Social capital and sleep disorders in Tibet, China

202109 bcvcVersion of RecordPublishe

Expression of H3K27me3 in Tibetan Patients with Gastric Cancer and Its Significance

Objective  To investigate the expression and its significance of H3K27me3 in Tibetan patients with gastric cancer.  Methods  Clinical and pathological data were retrospectively collected from Tibetan patients with gastric cancer in the Tibet Autonomous Region People's Hospital from August 2019 to August 2021 and Tibetan non-gastric cancer patients during the same period. The expression of H3K27me3 in gastric cancer tissues, corresponding adjacent normal gastric mucosa and normal gastric mucosa of Tibetan patients with non-gastric cancer tissues was detected by immunohistochemical method, and the differences of H3K27me3 expression between gastric cancer patients with different clinical and pathological characteristics was compared.  Results  A total of 54 Tibetan gastric cancer patients and 55 Tibetan non-gastric cancer patients who met the inclusion and exclusion criteria were enrolled. H3K27me3 was localized in the nucleus, and the nucleus showed brownish-yellow granular staining when positively expressed. The high expression rate of H3K27me3 in gastric cancer tissues was significantly higher than that in adjacent normal gastric mucosa tissue[64.8%(35/54) vs. 29.6%(16/54), P < 0.001]and normal gastric mucosal tissue of Tibetan patients with non-gastric cancer[64.8%(35/54) vs. 34.5%(19/55), P=0.002], and the high expression rate of H3K27me3 in the adjacent normal gastric mucosa tissue was not significantly different from that in normal gastric mucosal tissue of Tibetan patients with non-gastric cancer(P=0.683). H3K27me3 expression in gastric cancer tissues was not related to gender, age, degree of differentiation, depth of invasion, maximum tumor size, Lauren's classification, lymph node metastasis, vascular and nerve invasion and TNM stage.  Conclusions  H3K27me3 is highly expressed in gastric cancer tissues of Tibetan people in Tibet. There is no significant difference in H3K27me3 positive expression cells in adjacent tissues and normal gastric mucosa. The significance of H3K27me3 in Tibetan patients with gastric cancer is uncertain and requires further investigations

Complete mitochondrial genomes reveal the phylogenetic relationships of Duoma with eight representative sheep breeds and two ovis species

The Ovis aries Duoma breed is one of the most important alpine grassland-type sheep breeds in China. In this current study, we first reported the complete mitochondrial genome of Duoma sheep. Mitochondrial genome is 16,618 bp in length and exhibits the same typical structure as the other published sheep breeds. The genome contains 37 genes (22 tRNA, two rRNA, and 13 protein-coding genes (PCGs)) and a control region (D-loop region). Phylogenetic analysis shows that the Duoma sheep breed is closer to Ganjia sheep. Our findings will help the further evolution and conservation studies of Duoma sheep.</p

The Joint Contributions of Environmental Filtering and Spatial Processes to Macroinvertebrate Metacommunity Dynamics in the Alpine Stream Environment of Baima Snow Mountain, Southwest China

While macroinvertebrates are extensively investigated in many river ecosystems, meta-community ecology perspectives in alpine streams are very limited. We assessed the role of ecological factors and temporal dynamics in the macroinvertebrate meta-community assembly of an alpine stream situated in a dry-hot valley of Baima Snow Mountain, China. We found that spatial structuring and environmental filtering jointly drive the structure of macroinvertebrate meta-community, with relative contributions to the variance in community composition changing over time. RDA ordination and variation partitioning indicate that environmental variables are the most important predictors of community organization in most scenarios, whereas spatial determinants also play a significant role. Moreover, the explanatory power, identity, and the relative significance of ecological factors change over time. Particularly, in the years 2018 and 2019, stronger environmental filtering was found shaping community assembly, suggesting that deterministic mechanisms predominated in driving community dynamics. However, spatial factors had a stronger predictive power on meta-community structures in 2017, implying conspicuous dispersal mechanisms which may be owing to increased connectivity amongst sites. Thereby, we inferred that the alpine stream macroinvertebrate metacommunity composition can be regulated by the interaction of both spatial processes and environmental filtering, with relative contributions varying over time. Based on these findings, we suggest that community ecology studies in aquatic systems should be designed beyond single snapshot investigations

Development of a Machine Learning Forecast Model for Global Horizontal Irradiation Adapted to Tibet Based on Visible All-Sky Imaging

The Qinghai-Tibet Plateau is rich in renewable solar energy resources. Under the background of China’s “dual-carbon” strategy, it is of great significance to develop a global horizontal irradiation (GHI) prediction model suitable for Tibet. In the radiation balance budget process of the Earth-atmosphere system, clouds, aerosols, air molecules, water vapor, ozone, CO2 and other components have a direct influence on the solar radiation flux received at the surface. For the descending solar shortwave radiation flux in Tibet, the attenuation effect of clouds is the key variable of the first order. Previous studies have shown that using Artificial intelligence (AI) models to build GHI prediction models is an advanced and effective research method. However, regional localization optimization of model parameters is required according to radiation characteristics in different regions. This study established a set of AI prediction models suitable for Tibet based on ground-based solar shortwave radiation flux observation and cloud cover observation data of whole sky imaging in the Yangbajing area, with the key parameters sensitively tested and optimized. The results show that using the cloud cover as a model input variable can significantly improve the prediction accuracy, and the RMSE of the prediction accuracy is reduced by more than 20% when the forecast horizon is 1 h compared with a model without the cloud cover input. This conclusion is applicable to a scenario with a forecast horizon of less than 4 h. In addition, when the forecast horizon is 1 h, the RMSE of the random forest and long short-term memory models with a 10-min step decreases by 46.1% and 55.8%, respectively, compared with a 1-h step. These conclusions provide a reference for studying GHI prediction models based on ground-based cloud images and machine learning