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Luteolin is a natural flavonoid, which exists in many plants, including onions, broccoli, carrots, peppers, celery, olive oil, and mint. Luteolin is a dietary flavonoid with potent uric acid‐lowering and antioxidant bioactivities. To date, the mechanism by which luteolin alleviates hyperuricemia nephropathy (HN) still needs to be better defined. This study aims to evaluate the therapeutic efficacy of luteolin in a preclinical mouse model and in vitro. Luteolin was administered in the HN mice induced by the combination of potassium oxonate and hypoxanthine to evaluate the potential renoprotective effects in vivo. The NRK‐52E cells were stimulated with adenosine for in vitro evaluation. Hematoxylin and eosin staining, biochemical analysis, immunoblotting, immunofluorescence, and immunohistochemistry were performed for the histopathologic and mechanistic investigations. The results suggest that luteolin attenuated tubular dilation and epithelial atrophy in the renal tissue of HN mice. Further, luteolin improved biochemical indicators concerning renal functions and oxidative stress in vivo. Mechanistically, luteolin reduced the renal expressions of KIM‐1 and caspase‐3. Luteolin activated renal SIRT1/6 cascade and its downstream Nrf2‐mediated antioxidant pathway. Furthermore, luteolin elevated the renal expressions of ATP‐binding cassette subfamily G isoform 2 protein (ABCG2) and organic anion/cation transporters. In addition, livers of luteolin‐treated HN mice exhibited robust inhibition of xanthine oxidase. Together, our study shows that luteolin alleviates renal injury in the HN mice by activating urate excretion and Nrf2/HO‐1/NQO1 antioxidant pathways and inhibiting liver xanthine oxidase activity. Thus, luteolin may be a potential agent for the treatment of HN. [ABSTRACT FROM AUTHOR]

Deep‐level defects in semiconductor materials usually induce carrier trapping and non‐radiative recombination. However, defects caused by unintentional contaminants in antimony selenide (Sb2Se3) solar cells have rarely been reported. Herein, the correlation between defect properties and unintentional impurities in the Sb2Se3 absorber is investigated, which is prepared by injection vapor deposition with Sb2Se3 source purities ranging from 99.9% to 99.9999%. The analysis of deep‐level transient spectra reveals that an increase in impurity concentration does not result in new defect types. Nevertheless, the higher impurity level causes an increase in both the defect density and the capture cross section of the original defect. To address this challenge, defect engineering is developed to regulate the growth of the Sb2Se3 absorber. This strategy completely suppresses deepest defect states E3, a mixture of intrinsic defect (SbSe) and impurity Si related defect. As a result, the carrier lifetime increases significantly from 0.37 to 3.4 ps. This enables to fabricate Sb2Se3 solar cells with a power conversion efficiency of 10.41%. This work uncovers the characteristics of unintentional contaminant‐related defects, and provides a strategy for fabricating highly efficient Sb2Se3 solar cells with low‐purity source materials. [ABSTRACT FROM AUTHOR]

Ethoxylation is one of the common industrial process in which ethylene oxide (EO) is added to compounds containing active hydrogen atom (OH, COOH, SH, NH, etc.) to form surfactants. Alcohol ethoxylates are a major class of non‐ionic surfactants composed of an alkyl chain combined with few EO units. They are widely used in homecare products, personal care products, textiles, oilfield, construction, lubricants, food, paper, leather. The analysis of these ethoxylates possess several challenges since they contain 'n' number of EO units (n > 1). With increase in "n," the product becomes more and more viscous and the boiling point increases making it difficult to analyze by normal gas chromatography (GC) technique. This paper describes a method of derivatizing these ethoxylates so that they can be eluted on a high temperature GC. BSTFA (N, O‐bis (trimethylsilyl) trifluoroacetamide) is used as the derivatizing agent (silylating agent). The ethoxylate combines with BSTFA to form the corresponding trimethylsilylated (TMS) product, which have comparatively lower boiling point. Thus, we detect trimethyl silyl product, which is the resemblance for the ethoxylated product. In this paper, we present a quantitative GC method for the ethoxylates of a few simple alcohols (2‐ethyl hexanol, glycerin), and complex vegetable oils (castor oil). The products formed during the reaction have also been identified on a gas chromatograph coupled with mass spectrometer (GCMS). GCMS shows the mass corresponding to the TMS derivatized product. The derivatization technique not only helps in increasing the volatility of these compounds but also improves the chromatographic efficiency, selectivity, and enhances the detectability. [ABSTRACT FROM AUTHOR]

Ecological stoichiometry facilitates the understanding of biogeochemical cycles by studying the balance among multiple elements in ecosystems. However, the spatial patterns of soil stoichiometry and their responses to land use in desertified land are unclear. In this study, we selected 525 sample points to collect topsoil (0–20 cm) samples throughout China's Horqin Sandy Land and measured soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP). We then calculated stoichiometric ratios (C:N:P). SOC (8.7 g kg−1), TN (0.9 g kg−1), and TP (0.3 g kg−1) were lower in this region than in Chinese and global terrestrial ecosystems due to aeolian desertification. SOC, TN, C:P, and N:P were significantly (p < 0.05) higher in grassland, followed by woodland, cropland, and sandy land. This sequence may result from the large number of dead roots that participate in the SOC turnover in grassland. TP was significantly higher in cropland due to fertilization. C:N did not differ significantly (p > 0.05) among grassland, woodland, and cropland because of the strong coupling relationship between SOC and TN. The values of SOC, TN, TP, C:P, and N:P in the Horqin Sandy Land were high in the north (dominated by mountain woodland and grassland) and were low in the south (dominated by desertified land). SOC, TN, and TP contents and C:N:P ratios were mainly affected by mean annual temperature (29.6%), land use (11.5%), and bulk density (11.4%) through their influence on soil microbial metabolism, litter and nutrient input, and soil structure, respectively. The results provide information on the overall changes in soil stoichiometry in the Horqin Sandy Land and its responses to land‐use changes, and can therefore guide ecological restoration in semiarid regions affected by desertification in the modern context of climate change. [ABSTRACT FROM AUTHOR]

With the outbreak and pandemic of coronavirus disease‐2019 (COVID‐19), a huge number of people died of it. Apart from lung injuries, multiple organs have been confirmed to be impaired. In COVID‐19 time, primary wound healing processes always prolong, however, its possible underlying mechanisms are still unclear. Therefore, to overcome this clinical problem, clarifying its underlying mechanisms clearly is necessary and urgently needed. In this review, we summarized that COVID‐19 can prolong primary wound healing by inducing excessive inflammation and oxidative stress, disturbing immune system and haematological system, as well as influencing the functions and viability of epidermal stem cells (ESCs). Otherwise, we summarized that the strict control measures of blocking up COVID‐19 pandemic can also have side effects on primary wound healing process. [ABSTRACT FROM AUTHOR]

In this study, the vegetation and soils of different desertification landscapes (sandy grassland, and fixed, semi‐fixed, semi‐mobile, and mobile dunes) in the Hulun Buir Sandy Land were examined to quantify the impacts of desertification on plants, soils, and microbes, and the key limiting factors of restoration. Desertification caused soil quality to decline and led to an imbalance of nitrogen (N) and phosphorus (P) supplies (N:P ratios decreased significantly from 3.55–1.8, p < 0.05). Desertification did not change the stoichiometric relationships among plant carbon (C), N, and P at a community level, but promoted redistribution of nutrients from roots to aboveground tissues. The aboveground biomass N and P increased by 9.8% and 39.3%, respectively from grassland to mobile dunes, but these of the underground biomass decreased by 26.1% and 37.7%, respectively. N limitation (plant N:P < 10) occurred at the community level. Desertification led to the change of dominant species from perennial herbs to annual psammophytes, and plant diversity (from 1.15–0.79) and productivity (from 880.6 to 128.6 g m−2) first increased slightly (p > 0.05) and then decreased sharply (p < 0.05) with increasing desertification, but with no significant (p > 0.05) change of the microbial community. Redundancy analysis showed that the main environmental drivers were the soil N:P (with an explanation of 29.6%), followed by pH, electrical conductivity, and the soil's fine particles (with a total explanation of 24.3%). Based on these results, three reference frames were proposed for the restoration of the near‐original vegetation community. [ABSTRACT FROM AUTHOR]

The closed‐loop wireless power transfer (WPT) system can realize constant voltage output in the presence of perturbation. However, the parameter design of the controller is a difficult problem. The traditional trial‐and‐error method is time‐consuming and difficult to find optimal parameters. A parameter optimization strategy of control systems for uncertain WPT systems using the modified genetic algorithm (MGA) is proposed. Firstly, because the system has different characteristics at different periods, the simulation process is divided into three stages. The first one is the start‐up stage, in which we mainly consider the overshoot and the rate of the voltage rise. The second one is the tracking stage, in which the tracking time and switching loss are mainly considered. The third one is the stabilisation stage, in which the steady‐state error and switching loss are mainly considered. Secondly, three cost functions are designed according to the characteristics of the three stages, and then the optimal controller parameters of each stage are obtained by using MGA. Finally, the effectiveness of the proposed method is verified by simulation. The optimization results show that compared with the previous parameter optimization method, the optimal controller parameters obtained by the proposed method make the WPT system achieve better performance. [ABSTRACT FROM AUTHOR]

Background: Dual antiplatelet therapy is considered beneficial in acute ischemic stroke (AIS) patients with intracranial artery stenosis (ICAS), with more bleeding events. Ginkgolide is shown to reduce platelet activation after infarction, which might be of benefit in AIS. We aimed to explore the effect of Ginkgolide in AIS patients with ICAS. Methods: This was a randomized, double‐blinded, placebo‐controlled trial conducted at 61 centers in China. Within 72 h after onset, consecutive patients diagnosed as AIS with ICAS were randomized to either Ginkgolide or placebo treatment. The primary outcome was the composite of mortality and recurrent stroke (ischemic or hemorrhagic) during first 4 weeks in an intention‐to‐treat analysis. Secondary functional outcome was assessed by modified Rankin Scale and improvement of stroke severity was assessed by National Institution of Health Stroke Scale at day 28. Safety outcome was measured by the rate of severe adverse event (SAE). Results: There were 936 patients randomized to either Ginkgolide or placebo treatment. Their average age was 64.2 ± 10.4 years old and 36.0% of the patients were female. The composite index event occurred in six patients in placebo group, and none occurred in Ginkgolide group (risk ratio 1.01; 95% CI 1.00–1.02). There were more patients who achieved favorable outcome in Ginkgolide group, compared with that of the placebo group (OR 2.16, 95%CI 1.37–3.41). SAE occurred in five (1.1%) patients in the Ginkgolide group and three (0.6%) in the placebo group (OR0.60, 95CI% 0.14–2.53). Intracranial hemorrhage occurred in 1/473 (0.2%) in the placebo group. Conclusions: Ginkgolide, working as PAF antagonist, may reduce recurrent stroke in AIS with ICAS patients within 72 hours after onset. It might be an optional treatment in moderate‐to‐severe AIS patients with ICAS. (http://www.chictr.org.cn Number as ChiCTR‐IPR‐17012310). [ABSTRACT FROM AUTHOR]

Extreme climatic events have become a global concern. Understanding changes in these events is essential to support efforts to reduce their impacts. We investigated the spatial and temporal variation of 15 temperature and 11 precipitation extremal indices based on daily observations from 1960 to 2016 at 794 meteorological stations in mainland China. The regionally averaged temperature index trends were consistent with global warming. An abrupt change in the trends for warmth‐related indices mainly occurred from 1990 to 2000, and the year with an abrupt change for cold‐related indices appeared earlier (mainly around 1990). The numbers of warm days, warm nights, summer days, and tropical nights increased significantly. In contrast, the numbers of cool days, cool nights, ice days, and frost days decreased significantly. The coldest night temperature had a strong and significant warming trend (0.4°C·decade−1), whereas the number of frost days showed the fastest decrease (2.6 days·decade−1). The warmth and extremal indices decreased significantly with increasing latitude, whereas warming trends increased significantly with increasing longitude, and the warmth indices and extremal daily indices decreased with increasing elevation. The number of consecutive wet days decreased fastest, at 0.09 days·decade−1, and the daily intensity index increased fastest, at 0.09 mm·day−1 per decade. The extreme precipitation events decreased significantly with increasing latitude, but increased with increasing longitude. Large‐scale atmospheric circulation indices (the Arctic Oscillation and the Western Pacific Subtropical High Intensity and Area indices) and the Western Ridge Point strongly influenced the warm and cold extremes and contributed significantly to climate change in mainland China. The Western Ridge Point and Subtropical High Area were the dominant drivers of extreme temperature and precipitation events, respectively, in mainland China. [ABSTRACT FROM AUTHOR]

Summary: Multiple myeloma stem‐like cells (MMSCs) are responsible for initiation and relapse, though novel treatment paradigms that effectively eradicate MMSCs are yet to be developed. Selective inhibition of the cell cycle regulatory kinase Wee1 by MK1775 is being explored as a potential anti‐cancer therapeutic. We report that higher expression of Wee1 is correlated with poor survival in multiple myeloma (MM). The MM models and patient‐derived CD138+ plasma cells are particularly sensitive to the growth‐inhibitory effects of the Wee1 inhibitor MK1775. MK1775 induces Mus81‐Eme1 endonuclease‐mediated DNA damage in S‐phase cell cycle that results in a blockade of replication and then apoptosis. Furthermore, MK1775 strongly suppresses the features of stemness in vitro, in vivo and in primary CD138+ cells by decreasing ALDH1+ cell fraction and the expression of ALDH1. In addition, co‐treatment of MK1775 with bortezomib is synergistic in vitro and in vivo. Bortezomib, although it enhances ALDH1+ cells, when combined with MK1775 abrogates this stimulatory effect on stemness. Considering MM as an invariably incurable malignancy due to the presence of heterogenic myeloma stem‐like cells, our study presents inhibition of Wee1 as a promising targeted therapy for MM and provides a compelling rationale to further investigate the activity of MK1775 against myeloma in clinical settings. [ABSTRACT FROM AUTHOR]

Coatings incorporated with Sb2O3 were obtained on AZ31B magnesium alloy during micro‐arc oxidation (MAO) by adding Sb2O3 (0, 2, 4, 6, 8 g/L) into the electrolyte. The voltage of MAO process, microstructure, element distribution, thickness, phase analysis, microhardness, adhesion, and corrosion behavior of the coatings were, respectively, investigated. The results showed that the addition of different concentrations of Sb2O3 caused the voltage variation, which resulted in the changes in microstructure, element distribution, and phase composition of coatings, and further led to the improvement of coatings properties. It was found that the addition of Sb2O3 could effectively decrease the breakdown voltage, and made the voltage of micro‐arc oxidation stage change. Moreover, the presence of Sb2O3 influenced surface morphologies of the coatings. Additionally, with the increase in Sb2O3, the microhardness of coatings was 155.2, 199.78, 277.34, 267.53, and 127.93 HV, respectively; these were higher than substrate (68.5 HV). Moreover, the addition of Sb2O3 effectively improved adhesion. As the Sb2O3 increased, the corrosion rate was 2.19 × 10−4, 9.09 × 10−5, 4.10 × 10−5, 2.52 × 10−4, and 2.96 × 10−4 mm/a, respectively, and the corrosion resistance increased first and then decreased with the increase in Sb2O3. In sum, the optimal Sb2O3 concentration was 4 g/L. [ABSTRACT FROM AUTHOR]