Search

Improving the precision of aboveground biomass (AGB) estimation in lowland tropical forests is crucial to enhancing our understanding of carbon dynamics and formulating climate change mitigation strategies. This study proposes an AGB estimation method for lowland tropical forests in Xishuangbanna, which include various vegetation types, such as Pinus kesiya var. langbianensis, oak, Hevea brasiliensis, and other broadleaf trees. In this study, 2016 forest management inventory data are integrated with remote sensing variables from Landsat 8 OLI (L8) and Sentinel 2A (S2) imagery to estimate forest AGB. The forest age and aspect were utilized as stratified variables to construct the random forest (RF) models, which may improve the AGB estimation accuracy. The key findings are as follows: (1) through variable screening, elevation was identified as the main factor correlated with the AGB, with texture measures derived from a pixel window size of 7 × 7 perform best for AGB sensitivity, followed by 5 × 5, with 3 × 3 being the least effective. (2) A comparative analysis of imagery groups for the AGB estimation revealed that combining L8 and S2 imagery achieved superior performance over S2 imagery alone, which, in turn, surpassed the accuracy of L8 imagery. (3) Stratified models, which integrated aspect and age variables, consistently outperformed the unstratified models, offering a more refined fit for lowland tropical forest AGB estimation. (4) Among the analyzed forest types, the AGB of P. kesiya var. langbianensis forests was estimated with the highest accuracy, followed by H. brasiliensis, oak, and other broadleaf forests within the RF models. These findings highlight the importance of selecting appropriate variables and sensor combinations in addition to the potential of stratified modeling approaches to improve the precision of forest biomass estimation. Overall, incorporating stratification theory and multi-source data can enhance the AGB estimation accuracy in lowland tropical forests, thus offering crucial insights for refining forest management strategies. [ABSTRACT FROM AUTHOR]

In the past 10 years, adipose-derived stem cells (ADSCs) have been applied due to their pluripotency. Experimental tissues have been frequently obtained from mammals, including rabbits, mice and humans, but rarely from broilers, Gallus gallus domesticus. In the present study, ADSCs were obtained from 20-day-old broiler embryos. Primary ADSCs were sub-cultured to passage 37 in vitro. The surface markers of ADSCs, namely CD29, CD31, CD44, CD71 and CD73, were detected by reverse transcription polymerase chain reaction and immunofluorescence assays. The result indicated that CD29, CD44, CD71 and CD73 were expressed on the surface of cells at various passages, but not CD31. The growth curve of cells at the different passages had a typical sigmoidal shape. Furthermore, ADSCs were successfully induced to differentiate into osteoblasts, adipocytes and hepatocyte-like cells. The results denote that the ADSCs isolated from broilers have similar biological properties to those of ADSCs obtained from other animals. The present study provided a theoretical and experimental foundation for the use of poultry as a source of stem cells, and laid a foundation for adipose tissue engineering and strategies in regenerative medicine. [ABSTRACT FROM AUTHOR]

Overweight or obese women seeking pregnancy is becoming increasingly common. Human maternal obesity gives rise to detrimental effects during reproduction. Emerging evidence has shown that these abnormities are likely attributed to oocyte quality. Oxidative stress induces poor oocyte conditions, but whether mitochondrial calcium homeostasis plays a key role in oocyte status remains unresolved. Here, we established a mitochondrial Ca 2+ overload model in mouse oocytes. Knockdown gatekeepers of the mitochondrial Ca 2+ uniporters Micu1 and Micu2 as well as the mitochondrial sodium calcium exchanger NCLX in oocytes both increased oocytes mitochondrial Ca 2+ concentration. The overload of mitochondria Ca 2+ in oocytes impaired mitochondrial function, leaded to oxidative stress, and changed protein kinase A (PKA) signaling associated gene expression as well as delayed meiotic resumption. Using this model, we aimed to determine the mechanism of delayed meiosis caused by mitochondrial Ca 2+ overload, and whether oocyte-specific inhibition of mitochondrial Ca 2+ influx could improve the reproductive abnormalities seen within obesity. Germinal vesicle breakdown stage (GVBD) and extrusion of first polar body (PB1) are two indicators of meiosis maturation. As expected, the percentage of oocytes that successfully progress to the germinal vesicle breakdown stage and extrude the first polar body during in vitro culture was increased significantly, and the expression of PKA signaling genes and mitochondrial function recovered after appropriate mitochondrial Ca 2+ regulation. Additionally, some indicators of mitochondrial performance-such as adenosine triphosphate (ATP) and reactive oxygen species (ROS) levels and mitochondrial membrane potential-recovered to normal. These results suggest that the regulation of mitochondrial Ca 2+ uptake in mouse oocytes has a significant role during oocyte maturation as well as PKA signaling and that proper mitochondrial Ca 2+ reductions in obese oocytes can recover mitochondrial performance and improve obesity-associated oocyte quality., 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 © 2020 Zhang, Wang, Lu, Meng, Luo, Fu and Hou.)