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Aeolian processes in temperate grasslands (TGs) are unique because the plant growth–decay cycle, soil water, and land-use interactions affect the seasonal and inter-annual changes in dust events. Land-use types in Inner Mongolian TGs are unique (settled grazing and grass mowing) compared with those in Mongolian TGs. Since 2003, land use has been controlled by grassland protection legislation, which is intended to prevent desertification and dust storms. In this study, we used process-based ecosystem (DAYCENT) and statistical modeling, along with dust event observations from March to June of 1981–2015, to (1) identify critical land surface factors controlling dust emissions (vegetation components, live grass, standing dead grass, litter, and soil moisture) at typical and desert steppe sites in Inner Mongolia and (2) estimate the impact of controlled land-use legislation on dust events. The DAYCENT model realistically simulated the dynamics of the observed vegetation components and soil moisture in 2005–2015. At both sites, similar significant correlations were obtained between spring dust events and wind speed or a combination of all surface factors that retained anomalies (memory) from the preceding year. Among the surface factors, vegetation was a critical factor that suppressed dust in Inner Mongolian TGs, similar to that in Mongolian TGs. In the desert steppe, standing dead grass had the strongest memory and was significantly correlated with dust events, whereas no significant correlations were observed in the typical steppe. This suggests that, in a typical steppe region, heavy grazing and mowing result in few dead grasses, thereby inhibiting the prevention of dust events. Moreover, the simulations of dust events under controlled (light grazing) and uncontrolled (heavy grazing) land-use conditions demonstrated that the grassland protection legislation reduced the occurrence of dust events in typical and desert steppe sites by 25 and 40%, respectively, since 2003.

BackgroundChronic myeloid leukemia (CML) is an acquired hematopoietic stem malignant disease originating from the myeloid system. Long non-coding RNAs (lncRNAs) have been widely explored in cancer tumorigenesis. However, their roles in CML remain largely unclear.MethodsThe peripheral blood mononuclear cells (PBMCs) and CML cell lines (K562, KCL22, MEG01, BV173) were collected for in vitro research. Real-time quantitative polymerase chain reaction was used to determine the mRNA expression levels. Cell viability and apoptosis were analyzed by cell counting kit 8 and flow cytometry assays. The targeting relationships were predicted using Starbase and TargetScan and ulteriorly verified by RNA pull-down and luciferase reporter assays. Western blotting assay was performed to assess the protein expressions. N6-methyladenosine (m6A) modification sites were predicted by SRAMP and confirmed by Methylated RNA immunoprecipitation (MeRIP) assay.ResultsLncRNA nuclear-enriched abundant transcript 1 (NEAT1) expression levels were decreased in the CML cell lines and PBMCs of CML patients. Moreover, METTL3-mediated m6A modification induced the aberrant expression of NEAT1 in CML. Overexpression of NEAT1 inhibited cell viability and promoted the apoptosis of CML cells. Additionally, miR-766-5p was upregulated in CML PBMCs and abrogated the effects of NEAT1 on cell viability and apoptosis of the CML cells. Further, CDKN1A was proved to be the target gene of miR-766-5p and was downregulated in the CML PBMCs. Knockdown of CDKN1A reversed the effects of NEAT1.ConclusionThe current research elucidates a novel METTL3/NEAT1/miR-766-5p/CDKN1A axis which plays a critical role in the progression of CML.

Abstract In their Commentary Saber et al. (Part Fibre Toxicol 16: 44, 2019) argue that chronic inhalation studies in rats can be used for assessing the lung cancer risk of insoluble nanomaterials. The authors make several significant errors in their interpretation and representation of the underlying science. In this Letter to the Editor we discuss these inaccuracies to correct the scientific record. When the science is recounted accurately it does not support Saber et al’s statements and conclusions.

To study the inheritance of agricultural characteristics and lint yield traits in upland cotton parents and F1 crosses can provide the reference for breeding workers to select and improve certain traits. Four agronomic characters and four yield traits of 130 varieties (lines) and their 206 F1 crosses of upland cotton were analyzed on additive and effects by a genetic model with additive, dominance, and their interaction effects with the environment, genetic contribution analysis and decision coefficient analysis were conducted on the observation results. The results showed that these traits had rich genetic diversity with the coefficient of variation of the eight traits of the parents ranging from 5.54% to 50.83%, and the F1 crosses ranging from 3.96% to 55.87%. The additive contribution rate of agronomic traits (except for the first fruit branch node position to yield) to yield traits reached a very significant level (contribution rate was 4%--100%), and the additive contribution rate and dominant contribution rate of five petal boll rate and plant height to the boll number and boll weight and the contribution rate of dominant x environmental interaction reached a positive and significant level above 0.01. The genetic effects controlled by additive effects included the height of the first fruit branch, plant height, five petal boll rate, boll weight, and lint percentage, with lint percentage being the largest. Except for the small additive effect, plant height exhibits significant differences in dominant and additive effects x environmental interaction effects, dominance x environmental interaction effect and the generalized heritability of interaction were the maximum. The main decision-making and limiting traits for improving the lint yield in hybrid offspring of upland cotton had been identified. The coefficient of variation of upland cotton was relatively large. The five petal boll rate and plant height played a more important role in increasing the boll number and boll weight per plant. The boll number, boll weight, and lint percentage were the main decision-making traits for increasing the lint yield. [ABSTRACT FROM AUTHOR]

Dust storms are common in Mongolia and northern China, this is a serious threat to the ecological security and socioeconomic development of both countries and the surrounding areas. However, a complete quantitative study of the source area, affected area, and moving path of dust storm events (DSEs) in Mongolia and China is still lacking. In this study, we monitored and analyzed the spatiotemporal characteristics of the source area and affected areas of DSEs in Mongolia and China using the high-spatiotemporal-resolution images taken by the Himawari-8 satellite from March to June 2016–2020. In addition, we calculated the moving path of dusty weather using the HYSPLIT model. The results show that (1) temporality, a total of 605 DSEs occurred in the study area, with most of them occurring in April (232 DSEs), followed by May (173 DSEs). Spatially, the dust storm sources were concentrated in the arid inland areas such as the Taklimakan Desert (TK, 138 DSEs) and Badain Jaran Desert (BJ, 87 DSEs) in the western, and the Mongolian Gobi Desert (GD, 69 DSEs) in the central parts of the study area. (2) From the affected areas of the DSEs, about 60% of the DSEs in Mongolia started locally and then affected downwind China, as approximately 55% of the DSEs in the Inner Mongolia Desert Steppe and Hunshandake Sandy Land came from Mongolia. However, the DSEs in the TK located in the Tarim Basin of northwest China affected the entire study area, with only 31.3% belonging to the local dust. (3) From the moving path of the dusty weather, the dusty weather at the three meteorological stations (Dalanzadgad, Erlian, and Beijing), all located on the main transmission path of DSEs, was mainly transported from the windward area in the northwest, accounting for about 65.5% of the total path. This study provides a reliable scientific basis for disaster prevention and control, and has practical significance for protecting and improving human settlements.

Advancements in science enable researchers to constantly innovate and create novel biologics. However, the use of non-human animal models during the development of biologics impedes identification of precise in vivo interactions between the human immune system and treatments. Due to lack of this understanding, adverse effects are frequently observed in healthy volunteers and patients exposed to potential biologics during clinical trials. In this study, we evaluated and compared the effects of known immunotoxic biologics, Proleukin®/IL-2 and OKT3 in humanized mice (reconstituted with human fetal cells) to published clinical outcomes. We demonstrated that humanized mice were able to recapitulate in vivo pathological changes and human-specific immune responses, such as elevated cytokine levels and modulated lymphocytes and myeloid subsets. Given the high similarities of immunological side effects observed between humanized mice and clinical studies, this model could be used to assess immunotoxicity of biologics at a pre-clinical stage, without placing research participants and/or patients at risk.

Non-alcoholic fatty liver disease (NAFLD) has been on a global rise. While animal models have rendered valuable insights to the pathogenesis of NAFLD, discrepancy with patient data still exists. Since non-alcoholic steatohepatitis (NASH) involves chronic inflammation, and CD4+ T cell infiltration of the liver is characteristic of NASH patients, we established and characterized a humanized mouse model to identify human-specific immune response(s) associated with NAFLD progression. Immunodeficient mice engrafted with human immune cells (HIL mice) were fed with high fat and high calorie (HFHC) or chow diet for 20 weeks. Liver histology and immune profile of HIL mice were analyzed and compared with patient data. HIL mice on HFHC diet developed steatosis, inflammation and fibrosis of the liver. Human CD4+ central and effector memory T cells increased within the liver and in the peripheral blood of our HIL mice, accompanied by marked up-regulation of pro-inflammatory cytokines (IL-17A and IFNγ). In vivo depletion of human CD4+ T cells in HIL mice reduced liver inflammation and fibrosis, but not steatosis. Our results highlight CD4+ memory T cell subsets as important drivers of NAFLD progression from steatosis to fibrosis and provides a humanized mouse model for pre-clinical evaluation of potential therapeutics.

Microporous polyethylene (PE) membrane is a representative lithium‐ion battery (LIB) separators but regularly shrinks especially in high‐temperature conditions, and is facilely pierced while growing Li dendrites, leading to severe consequences such as short circuits, thermal runaway, and even explosion. Herein, this article reports a quasi‐continuous strategy that utilizes in situ enamel mineralization engineering followed by thermal treatment to easily develop a large‐area, 3D interlaced hydroxyapatite nanosheets array‐reinforced PE nanocomposite separator with robust mechanical properties and excellent resistance to thermal shrinkage. Specifically, the 120 °C‐heated nanocomposite possesses excellent breaking stress, an ultrahigh toughness of ≈434.4 MJ m−3, and an enhanced friction coefficient of ≈0.69, which are distinctly higher than those of commercial PE separators, respectively, and far exceeding those of reported ceramic modified‐PE separators. The elongation of the resultant nanocomposite can achieve an extraordinary ≈2456.4% without any fracture under a 180 °C‐heating temperature. In situ observation and finite element simulation indicate that the impressive mechanical and thermostable integration profits from the co‐effect of efficient energy dissipation at organic–inorganic interfaces and mechanically interlocked, mutually‐supported hybrid microstructure. The enamel‐inspired separator can be potentially applied in safer high‐temperature LIBs and this strategy provides a valuable guide to develop other high‐performance polymer‐based nanocomposites. [ABSTRACT FROM AUTHOR]

Aims: Veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) is an important technique for the treatment of refractory cardiogenic shock and cardiac arrest; however, the early management of ventricular fibrillation/ventricular tachycardia (VF/VT), within 72 h of VA‐ECMO, and its effects on patient prognosis remain unclear. Methods and results: We retrospectively analysed patients at the First Affiliated Hospital of Nanjing Medical University who underwent VA‐ECMO between January 2017 and March 2022. The patients were divided into two groups, VF/VT and nVF/VT, based on whether or not VF/VT occurred within 72 h after the initiation of VA‐ECMO. We utilized logistic regression analysis to evaluate the independent risk factors for VF/VT in patients undergoing VA‐ECMO and to ascertain whether the onset of VF/VT affected 28 day survival rate, length of intensive care unit stay, and/or other clinical prognostic factors. Subgroup analysis was performed for the VF/VT group to determine whether defibrillation affected prognosis. In the present study, 126 patients were included, 65.87% of whom were males (83/126), with a mean age of 46.89 ± 16.23, a 28 day survival rate of 57.14% (72/126), an incidence rate of VF/VT within 72 h of VA‐ECMO initiation of 27.78% (35/126), and 80% of whom (28/35) received extracorporeal cardiopulmonary resuscitation. The incidence of VF/VT resulting from cardiac arrest at an early stage was significantly higher than that of refractory cardiogenic shock (80% vs. 20%; P = 0.022). The restricted cubic spline model revealed a U‐shaped relationship between VF/VT incidence and initial heart rate (iHR), and multivariate logistic regression analysis showed that an iHR > 120 b.p.m. [odds ratio (OR) 6.117; 95% confidence interval (CI) 1.672–22.376; P = 0.006] and hyperlactataemia (OR 1.125; 95% CI 1.016–1.246; P = 0.023) within 1 h of VA‐ECMO initiation were independent risk factors for the occurrence of VF/VT. VF/VT was not found to be associated with the 28 day survival of patients undergoing VA‐ECMO support, nor did it affect other secondary endpoints. Defibrillation did not alter the overall prognosis in patients with VF/VT during VA‐ECMO. Conclusions: An iHR > 120 b.p.m. and hyperlactataemia were independent risk factors for the occurrence of VF/VT within 72 h of VA‐ECMO initiation. The occurrence of VF/VT does not affect, nor does defibrillation in these patients improve the overall patient prognosis. Trial registration: ChiCTR1900026105. [ABSTRACT FROM AUTHOR]

Fires formed by the high gas protrusion in coal mines are difficult and risky to extinguish during the mine closure process due to the mine's large closed range and underground gas stock. To achieve efficient and safe unsealing, reduce the risk of re-ignition and gas explosion, and accurately determine the fire extinguishing effect, a dual-drive rapid fire extinguishing technology is proposed. This technology involves ground precise positioning of drilling holes, rapid and large flow of liquid nitrogen injection, and curtain grouting to block fires in ultra-large high-gas mines. The practical results demonstrate that the implementation of surface injection of liquid nitrogen for fire extinguishing and cooling, and plugging effectively reduces the concentration of CO in the underground space from 230 PPm to 0 PPm, and decreases the CH4 concentration content from 90% to less than 0.75%. The fire extinguishing and cooling effect is fast and significant. A technical scheme for unsealing the fire area of the whole mine is formulated on a large scale based on the state of pumping and releasing pressure in the closed space of the mine. This scheme has important guiding significance for safety rescue and rescue operations after serious fire accidents occur in similar high-gas prominent mines. [ABSTRACT FROM AUTHOR]

Bridged benzazepine scaffolds, possessing unique structural and physicochemical activities, are widespread in various natural products and drugs. The construction of these skeletons often requires elaborate synthetic effort with low efficiency. Herein, we develop a simple and divergent approach for constructing various bridged benzazepines by a photocatalytic intermolecular dearomatization of naphthalene derivatives with readily available α‐amino acids. The bridged motif is created via a cascade sequence involving photocatalytic 1,4‐hydroaminoalkylation, alkene isomerization and cyclization. Interestingly, the diastereoselectivity can be regulated through different reaction modes in the cyclization step. Moreover, aminohydroxylation and its further bromination have also been demonstrated to access highly functionalized bridged benzazepines. Preliminary mechanistic studies have been performed to get insights into the mechanism. This method provides a divergent synthetic approach for construction of highly functionalized bridged benzazepines, which have been otherwise difficult to access. [ABSTRACT FROM AUTHOR]

A substantial body of evidence suggests that indoor mold exposure is a cause of allergic and respiratory diseases in humans. While models exist for assessing the risk of mold growth on building materials, few study the characteristics of mold growth after germination. This study conducted mold growth experiments in a constant temperature chamber, using four temperature settings of 15, 20, 25 and 30 °C, and three relative humidities of 56 to 61%, 75 to 76% and 83 to 86%. A mold growth prediction model was established using temperature and relative humidity. The accuracy of the model was verified by comparing the sampling and the predicted values in a laboratory environment. The results indicated that reducing the environmental temperature and relative humidity could significantly inhibit the growth of mold, although the inhibitory effects varied. Temperature might play a more critical role. At higher temperatures (25 °C and 30 °C), the growth rate and lag time of mold tended to be consistent and there were differences in the maximum diameter. In the predictive model, the polynomial secondary model for the maximum growth rate and lag time and the Arrhenius–Davey secondary model for the maximum diameter (A) had good predictive effects (Adj.R2 > 0.850). It is speculated that temperature is the key factor affecting the maximum growth diameter of mold. The mold growth prediction model could better predict the growth of mold in actual environments without wind Adj.R2 > 0.800), but the accuracy of the model decreased under windy conditions (wind velocity < 1 m/s). The mold growth predictive model we established could be used to predict the growth characteristics of mold in windless environments. It also provides control suggestions for the regulation of temperature and relative humidity in indoor environments, supporting indoor thermal environment management and pollutant control, and ensuring indoor human health. [ABSTRACT FROM AUTHOR]

Abstract Background Xenotransplantation of patient-derived AML (acute myeloid leukemia) cells in NOD-scid Il2rγ null (NSG) mice is the method of choice for evaluating this human hematologic malignancy. However, existing models constructed using intravenous injection in adult or newborn NSG mice have inferior engraftment efficiency, poor peripheral blood engraftment, or are difficult to construct. Methods Here, we describe an improved AML xenograft model where primary human AML cells were injected into NSG newborn pups intrahepatically. Results Introduction of primary cells from AML patients resulted in high levels of engraftment in peripheral blood, spleen, and bone marrow (BM) of recipient mice. The phenotype of engrafted AML cells remained unaltered during serial transplantation. The mice developed features that are consistent with human AML including spleen enlargement and infiltration of AML cells into multiple organs. Importantly, we demonstrated that although leukemic stem cell activity is enriched and mediated by CD34+CD117+ subpopulation, CD34+CD117− subpopulation can acquire CD34+CD117+ phenotype through de-differentiation. Lastly, we evaluated the therapeutic potential of Sorafenib and Regorafenib in this AML model and found that periphery and spleen AML cells are sensitive to these treatments, whereas BM provides a protective environment to AML. Conclusions Collectively, our improved model is robust, easy-to-construct, and reliable for pre-clinical AML studies.