Search

Study region: The study area is located in Guizhou province, the centre of the karst region in southwest China. Study focus: As a typical karst region, Guizhou has long faced challenges with water scarcity. Quantifying water use efficiency (WUE) is crucial for the efficient use of water resources and sustainable management. This study examined the spatio-temporal evolution patterns and its driving factors on WUE in Guizhou using Theil-Sen's slope, partial correlation methods, and the geographic detector model. New hydrological insights for the region: (1) The multi-annual mean WUE of non-karst region (NKR, 2.75 gC kg−1 H2O yr−1) is higher than that of karst region (KR, 2.10 gC kg−1 H2O yr−1) during 2001–2020. (2) The rate of increase of WUE was three times higher in KR than in NKR. (3) Precipitation and temperature were identified as the key factors influencing WUE. Interactions between each environmental factors were observed to have both bi-variate and non-linear enhancement effects. Notably, in the NKR, soil moisture, vegetation type and leaf area index were the dominant factors influencing WUE, with interactions between environmental factors had both enhanced and weakened effect on WUE. (4) The synergistic effects of these interactions exceeded the individual or cumulative effects of the two environmental factors. These findings contribute to our understanding of the environmental factors driving changes in WUE in the KR.

Background: For translational research on lung diseases it is desirable to have human organoids which resemble features of human tissue. Adult stem cells obtained from human bronchial epithelium can be differentiated to little tissue follicles, so-called bronchospheres. Aim of the study was to characterize structural details of bronchospheres treated with control media, lipopolysaccharide, and flagellin during the differentiation phase. Basic procedures: Human bronchial epithelial stem cells were prepared from surgical specimens and differentiated in Matrigel to bronchospheres. Histology and transmission electron microscopy revealed the cellular structure of the bronchospheres. Main findings: Follicles with a diameter of about 120 µm were confined by a bilayered epithelium with surface differentiation towards the inner lumen of the follicle and junctional complexes. Microvilli, kinocilia as well as secretory cells were found. Treatment with the bacterial flagellin resulted in the formation of secretory granules and inhibited the occurrence of kinocilia. Principal conclusions: Despite clear limitations such as lacking of smooth muscles and columnar epithelium human bronchospheres are an interesting tool for translational research. They can be useful for studies addressing developmental processes, infections, drug testing and toxicology.