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Extreme droughts strongly impact grassland ecology, both functionally and structurally. However, a comprehensive understanding of the drought impacts on the ecosystem stability is critical for its sustainable development under changing climate. We experimentally report the impact of extreme drought on the temporal stability of aboveground net primary productivity (ANPP) and belowground net primary productivity (BNPP) in a desert steppe of northern China. The relative importance evaluation of extreme drought, soil properties, species asynchrony, taxonomic, functional, and phylogenetic diversity was performed using structural equation modeling (SEM) to measure the temporal ANPP and BNPP stabilities. Our findings suggested that extreme drought decreased BNPP stability but did not affect ANPP stability. Extreme drought reduced taxonomic and phylogenetic diversity, ANPP, and soil water content but did not affect species asynchrony, functional diversity, or BNPP. Species richness, Shannon-Wiener index, and soil water content were positively correlated with BNPP stability. The SEM results showed a drought-mediated indirect weakening of BNPP stability via modification of species richness. Asynchrony of species unrelated to drought, however, directly affected ANPP stability. The mechanisms underlying the response determination of ANPP and BNPP stability to extreme drought in desert steppe varied notably. Depending on the species asynchrony, ANPP reduced by extreme drought could maintain higher stability. However, extreme drought lowered BNPP stability by altering species richness.

Deubiquitinates (DUBs) alter the stabilities, localizations or activities of substrates by removing their ubiquitin conjugates, which are closely related to the development of inflammatory response. Here, we show that ubiquitin-specific protease 47 (USP47) prevents inflammation development in inflammatory bowel disease (IBD). Compared with wild-type mice, Usp47 knockout mice are more susceptible to dextran sodium sulfate (DSS)-induced acute and chronic colitis with higher inflammatory cytokines expression and severe intestinal tissue damage. Chimeric mouse experiments suggest that non-hematopoietic cells mainly contribute to the phenotype. And, DSS-induced colitis of the Usp47 knockout mice depends on commensal bacteria. Mechanistically, down-regulation of USP47 aggravates the activation of NF-κB signaling pathway by increasing the K63-linked poly-ubiquitination of tumor necrosis factor receptor-associated factor 6 (TRAF6) in intestinal epithelial cells. Furthermore, the expression of USP47, negatively correlated with the degree of inflammation, is lower at colonic inflammatory lesions than that non-inflammatory sites from the intestine from ulcerative colitis (UC) and Crohn's disease (CD) patients. These data, taken together, indicate that USP47 regulates intestinal inflammation through de-ubiquitination of K63-linked poly-ubiquitination TRAF6 in intestinal epithelial cells.

Drought significantly impacts ecosystem structure and function, especially the transformation rates of soil carbon and nitrogen. This study explores how drought affects ecosystem respiration (R-e), methane (CH4) uptake and nitrous oxide (N2O) emissions in temperate desert steppes and the underlying mechanisms. Methods An in-situ experiment was conducted in the Inner Mongolia desert steppe in northern China to study the effect of drought on R-e, CH4 and N2O fluxes. Structural equation modeling (SEM) was used to establish the relationship between R-e, CH4 uptake and N2O emissions and plant functional traits and environmental factors. Results Ecosystem respiration and CH4 uptake were both significantly reduced by chronic drought (66 % precipitation reduction from 1 May to 31 August) but not by pulse drought (100 % precipitation reduction in June and July). In contrast, no significant impact on N2O emissions was observed under chronic or pulse drought. There were no significant direct effects of soil moisture on R-e, CH4 uptake or N2O emissions. However, soil moisture had an important indirect effect on R-e, CH4 uptake and N2O emissions, mainly through its influence on plant functional traits, plant above-ground biomass and soil nutrients. Plant biomass and soil temperature were the key indicators of R-e, and plant leaf nitrogen content was the key plant trait associated with N2O emissions. In contrast, plant specific leaf area and biomass were the key traits associated with CH4 uptake. Conclusions Overall, R-e and CH4 uptake were reduced by chronic drought in this desert steppe, but there was no significant effect on N2O emissions. Ecosystem respiration, CH4 uptake and N2O emissions were associated with plant functional traits. This provides new insight for the understanding of soil carbon and nitrogen dynamics in desert steppe systems under drought conditions and an important theoretical basis for the revision of model parameters.

In this paper, a self-healing composite coating on its surface by in situ hydrothermal-ion exchange hot pressing with silane method was synthesized on 3D-printed stainless steel, and self-healing performance and mechanism of the coating were studied during static corrosion. Based on the excellent physical and chemical properties of molecular sieve and the characteristics of environmental protection and high mechanical strength, ZSM-5 molecular sieve was selected as nano-container to load corrosion inhibitor cerium ion, and silane coupling agent was selected as binder to enhance the bonding force with the coating and the surface of 3D-printed stainless steel. The surface morphology, element distribution and composition of the coating were studied by scanning electron microscope (SEM), energy-dispersive spectrometer (EDS) and x-ray diffraction (XRD), respectively. The self-healing process and mechanism of the coating were studied by SEM, EDS, localized electrochemical impedance spectroscopy (LEIS), three-dimensional microscope and atomic force microscope. Research shows that the coating has obvious self-healing ability during static corrosion.

A novel hybrid perfusion manipulator (HPM) with five degrees of freedom (DOFs) is introduced by combining the 5PUS-PRPU (P, R, U, and S represent prismatic, revolute, universal, and spherical joint, respectively) parallel mechanism with the 5PRR reconfigurable base to enhance the perfusion efficiency of the large-scale spherical honeycomb thermal protection layer. This study mainly presents the dimensional synthesis of the proposed HPM. First, the inverse kinematics, including the analytic expression of the rotation angles of the U joint in the PUS limb, is obtained, and mobility analysis is conducted based on screw theory. The Jacobian matrix of 5PUS-PRPU is also determined with screw theory and used for the establishment of the objective function. Second, a global and comprehensive objective function (GCOF) is proposed to represent the Jacobian matrix’s condition number. With the genetic algorithm, dimensional synthesis is conducted by minimizing GCOF subject to the given variable constraints. The values of the designed variables corresponding to different configurations of the reconfigurable base are then obtained. Lastly, the optimal structure parameters of the proposed 5-DOF HPM are determined. Results show that the HPM with the optimized parameters has an enlarged orientation workspace, and the maximum angle of the reconfigurable base is decreased, which is conducive to improving the overall stiffness of HPM.

The zeolite membrane as a corrosion-resistant membrane has green environmental protection, high-temperature resistance, high-mechanical strength, and other characteristics, which has attracted much attention. However, due to the very different surface properties between metals and inorganics, the embodiment of high-binding force membrane is a major difficulty in the current zeolite membrane synthesis technology. Research has been conducted on the silane (YDH-151)/zeolite (TS-1) composite anticorrosive membrane in Ti-6Al-4V alloy surface, and on the modification effect by using graphene oxide (GO), as well as the membrane formation mechanism after being modified. Scanning electron microscope and 3D laser confocal microscope (3D LCSM) were used to study the effect of GO on the modified silane/zeolite composite anticorrosion membrane, and electrochemical methods, contact angle, bonding force, Fourier transform infrared ray were used to study the modification effect and the membrane formation mechanism and process after being modified. Microscopic observations show that GO causes the zeolite particles to accelerate to accumulate, hinders the lateral membrane formation of TS-1 zeolite which forms thus non-negligible pores or defects. It also reduces the density of the zeolite membrane, and the hydrophobicity and binding force of the composite membrane. However, GO can effectively decrease the corrosion current density and greatly enhance the corrosion resistance of the membrane. YDH-151 undergoes dehydration condensation reaction with metal surface and zeolite, and graft reaction with GO, forming a dense YDH-151/GO/TS-1 composite membrane on the surface of Ti-6Al-4V alloy, with a corrosion resistance rate of 99.8%.

This paper reports on a method of synthesizing silicalite-1 molecular sieve-based anti-corrosive film on stainless steel surface. The corrosion resistance and mechanisms of four preparation methods were studied. The results show that the silicalite-1 anti-corrosive film prepared by silane hot pressing shows the best surface, crystallinity, and anti-corrosion performance. On this basis, the film formation and anti-corrosive mechanisms of silicalite-1 anti-corrosion film on stainless steel surfaces were analyzed.

T-cell acute lymphoblastic leukemia (T-ALL) is a highly aggressive leukemia that is primarily caused by aberrant activation of the NOTCH1 signaling pathway. Recent studies have revealed that posttranslational modifications, such as ubiquitination, regulate NOTCH1 stability, activity, and localization. However, the specific deubiquitinase that affects NOTCH1 protein stability remains unestablished. Here, we report that ubiquitin-specific protease 7 (USP7) can stabilize NOTCH1. USP7 deubiquitinated NOTCH1 in vivo and in vitro, whereas knockdown of USP7 increased the ubiquitination of NOTCH1. USP7 interacted with NOTCH1 protein in T-ALL cells, and the MATH and UBL domains of USP7 were responsible for this interaction. Depletion of USP7 significantly suppressed the proliferation of T-ALL cells in vitro and in vivo, accompanied by downregulation of the NOTCH1 protein level. Similarly, pharmacologic inhibition of USP7 led to apoptosis of T-ALL cells. More importantly, we found that USP7 was significantly upregulated in human T-ALL cell lines and patient samples, and a USP7 inhibitor exhibited cell cytotoxicity toward primary T-ALL cells, indicating the clinical relevance of these findings. Overall, our results demonstrate that USP7 is a novel deubiquitinase that stabilizes NOTCH1. Therefore, USP7 may be a promising therapeutic target in the currently incurable T-ALL., Cancer pathology: Cutting a lifeline of lymphoblastic leukemia Inhibiting the protein ubiquitin-specific protease 7 (USP-7) may offer a treatment option for patients with T-cell acute lymphoblastic leukemia (T-ALL), an incurable and aggressive cancer. T-ALL is primarily caused by aberrant activation of the protein NOTCH1, which regulates gene expression relating to cell survival, proliferation, and metastasis. Ying-Li Wu, from China’s Shanghai Jiao Tong University School of Medicine, and a team of researchers report that, in their experiments, USP-7 prevented the breakdown of NOTCH1 by removing the protein tag that would normally signal it for degradation. In addition, USP-7 expression was upregulated in all human T-ALL cells and samples tested. Inhibition of USP-7 suppressed the proliferation of T-ALL cells in vitro and in vivo. These results reveal the role of USP-7 in the pathophysiology of T-ALL and offer USP-7 as a promising potential therapeutic target.

The aim of this study was to determine whether the number of passages affected the developmental pluripotency of embryonic stem (ES) cells as measured by the attainment of adult fertile mice derived from embryonic stem (ES) cell/tetraploid embryo complementation. Thirty-six newborns were produced by the aggregation of tetraploid embryos and hybrid ES cells after various numbers of passages. These newborns were entirely derived from ES cells as judged by microsatellite DNA, coat-color phenotype, and germline transmission. Although 15 survived to adulthood, 17 died of respiratory failure, and four were eaten by their foster mother. From the 15 mice that reached adulthood and that could reproduce, none arose from ES cells at passage level 15 or more. All 15 arose from cells at passages 3-11. Our results demonstrate that the number of passages affects the developmental pluripotency of ES cells.