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Climate warming may induce growth decline in warm-temperate areas subjected to seasonal soil moisture deficit, whereas increasing atmospheric CO2 concentration (Ca) is expected to enhance tree growth. An accurate understanding of tree growth and physiological processes responding to climate warming and increasing Ca is critical. Here, we analyzed tree-ring stable carbon isotope and wood anatomical traits of Pinus tabuliformis from Qinling Mountains in China to understand how lumen diameter (LD) determining potential hydraulic conductivity and cell-wall thickness (CWT) determining carbon storage responded to climate and Ca. The effects of climate and Ca on intrinsic water-use efficiency (iWUE) were isolated, and iWUE values due to only-climate (iWUEClim) and only-CO2 effects (iWUECO2) were obtained. During a low-iWUE period, the influences of climate on earlywood (EW) LD and latewood (LW) CWT prevailed. During a high-iWUE period, CO2 fertilization promoted cell enlargement and carbon storage but this was counteracted by a negative influence of climate warming. The limiting direct effects of iWUEClim and indirect effects of climate on EW LD were greater than on LW CWT. P. tabuliformis in temperate forests will face a decline of growth and carbon fixation, but will produce embolism-resistant tracheids with narrow lumen responding to future hotter droughts. [ABSTRACT FROM AUTHOR]

Purpose: Dynamic modeling of large-scale periodic trusses is critical for the structure optimization and vibration control of the truss. Due to the large size and complex modeling, the equivalent model of periodic trusses has been of concern to researchers. Methods: This article suggested an equivalent model of a periodic truss with concentrated mass and rigid joints using finite element and energy equivalent techniques. The kinetic energy and strain energy of the truss were first calculated using the finite element method, and then the energy equivalent model of the periodic truss was developed. This section also included a detailed description of the solution method. Second, the effectiveness of the model and the influence of the concentrated mass and the bending deformation of the truss members on the accuracy of the equivalent model have been carried out successively. Results: The results demonstrate that the vibration and static characteristics of the equivalent model are in good agreement with the full-scale periodic truss. Meanwhile, this study also indicates that the bending deformation of the truss member has little effect on the low-order mode. By contrast, the concentrated mass, such as truss joints, has a greater impact on dynamic characteristics. Conclusions: As a result, the equivalent model reveals the relationship between the physical parameters of the periodic truss and its dynamic characteristics, which has guiding significance for the dynamic analysis and control law design of large-scale flexible space trusses. [ABSTRACT FROM AUTHOR]

These authors contributed equally: LY Zhao, CC Yao, XY Xing, T Jing. The original version of this Article contained an error in figure legend 2f, which incorrectly read '(f) Immunofluorescence co-staining of GATA4 (green) with JUN (red, upper panel), ENO1 (red, middle panel), and DEFB119 (red, lower panel) in human testicular paraffin sections at three ages.'. The correct version states '(f) Immunofluorescence co-staining of GATA4 (red) with JUN (green, upper panel), ENO1 (green, middle panel), and DEFB119 (green, lower panel) in human testicular paraffin sections at three ages.'. This has been corrected in both the PDF and HTML versions of the Article. [Extracted from the article]

Clinical efficacy of treatments against non-obstructive azoospermia (NOA), which affects 1% of men, are currently limited by the incomplete understanding of NOA pathogenesis and normal spermatogenic microenvironment. Here, we profile >80,000 human testicular single-cell transcriptomes from 10 healthy donors spanning the range from infant to adult and 7 NOA patients. We show that Sertoli cells, which form the scaffold in the testicular microenvironment, are severely damaged in NOA patients and identify the roadmap of Sertoli cell maturation. Notably, Sertoli cells of patients with congenital causes (Klinefelter syndrome and Y chromosome microdeletions) are mature, but exhibit abnormal immune responses, while the cells in idiopathic NOA (iNOA) are physiologically immature. Furthermore, we find that inhibition of Wnt signaling promotes the maturation of Sertoli cells from iNOA patients, allowing these cells to regain their ability to support germ cell survival. We provide a novel perspective on the development of diagnostic methods and therapeutic targets for NOA. Non-obstructive azoospermia affects 1% of men. Here, authors perform single-cell transcriptomic analysis of human testicular cells from healthy donors and non-obstructive azoospermia patients and find that inhibition of Wnt signaling promotes the maturation of Sertoli cells from patients. [ABSTRACT FROM AUTHOR]