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Deep space exploration has risen in interest among scientists in recent years, with soft landings being one of the most straightforward ways to acquire knowledge about the Moon. In general, landing mission success depends on the selection of landing zones, and there are currently few effective quantitative models that can be used to select suitable landing zones. When automatic landing zones are selected, the grid method used for data partitioning tends to miss potentially suitable landing sites between grids. Therefore, this study proposes a new engineering-constrained approach for landing zone selection using LRO LOLA-based slope data as original data based on the sliding window method, which solves the spatial omission problem of the grid method. Using the threshold ratio, mean, coefficient of variation, Moran's I, and overall rating, this method quantifies the suitability of each sliding window. The k-means clustering algorithm is adopted to determine the suitability threshold for the overall rating. The results show that 20 of 22 lunar soft landing sites are suitable for landing. Additionally, 43 of 50 landing sites preselected by the experts (suitable landing sites considering a combination of conditions) are suitable for landing, accounting for 90.9% and 86% of the total number, respectively, for a window size of 0.5° × 0.5°. Among them, there are four soft landing sites: Surveyor 3, 6, 7, and Apollo 15, which are not suitable for landing in the evaluation results of the grid method. However, they are suitable for landing in the overall evaluation results of the sliding window method, which significantly reduces the spatial omission problem of the grid method. In addition, four candidate landing regions, including Aristarchus Crater, Marius Hills, Moscoviense Basin, and Orientale Basin, were evaluated for landing suitability using the sliding window method. The suitability of the landing area within the candidate range of small window sizes was 0.90, 0.97, 0.49, and 0.55. This indicates the capacity of the method to analyze an arbitrary range during blind landing zone selection. The results can quantify the slope suitability of the landing zones from an engineering perspective and provide different landing window options. The proposed method for selecting lunar landing zones is clearly superior to the gridding method. It enhances data processing for automatic lunar landing zone selection and progresses the selection process from qualitative to quantitative. [ABSTRACT FROM AUTHOR]

Identifying saline soils is of great importance for protecting land resources and for the sustainable development of agriculture. Total soil salinity (TSS) is the most commonly used indicator for determining soil salinization, but the application of soil geochemical data is rarely reported. In general, there is a significant relationship between TSS and the content of soil-soluble Na, which can be estimated by the difference between the bulk-soil Na2O content and its background value. In this study, the partial least squares regression (PLSR) method was employed to calculate the Na2O background value via a regression model between Na2O and SiO2, Al2O3, TFe2O3, Cr, Nb, and P in a 1:250,000 scale regional geochemical data set of soils in Jilin Province, NE China. We defined δNa as the difference between the bulk-soil Na2O value and the regression background value, which can be used as a geochemical indicator to identify saline soils. One hundred and five samples with known TSS contents in the study area were selected to test the capability of the indicator δNa. The result shows that the identification accuracy can be up to 75%, indicating that the indicator can provide a new means for saline soil identification. [ABSTRACT FROM AUTHOR]

Structural and interfacial instabilities hinder the large-scale application of Ni-rich layered LiNi1-xCoxMnyO2 (x + y ≤ 0.4) cathode materials to electric vehicle (EV). Therefore, this manuscript introduces synergistic modification of Ce doping and CeO2 coating to enhance electrochemical performance of LiNi0.9Co0.05Mn0.05O2 cathode material. Ce doping improves the inner structure stability, reduces the cation mixing, and extends the lithium ion diffusion pathway due to high bond dissociation energy of Ce–O and large rad radius of cerium ion. CeO2 coating layer protects the cathode/electrolyte interface from side reactions. The testing results of SEM, XPS, etc. prove that Ce doping and coating are introduced into LiNi0.9Co0.05Mn0.05O2 cathode material successfully. Ce doping and coating modification enhance cycling performance. The capacity retention of modified sample is 93.3% at 1 C rate between 2.8 and 4.3 V after 100 cycles. The synergistic effects of cerium doping and ceria coating modification on the electrochemical performance and structural stability could be extended to develop high capacity cathode. [ABSTRACT FROM AUTHOR]

The blue light hazard (BLH) and luminous efficacy of a source ( η V ) are associated with the photobiological safety and energy saving of light-emitting diodes (LEDs), respectively. In this study, we used genetic algorithm (GA) to optimize the BLH, η V , and color rendering parameters of five-chip hybrid white LEDs. Based on the optimal results, we used five-chip LEDs to obtain the hybrid white light. Their peak wavelengths were 461.5 (blue), 523.9 (green), 588.2 (orange), 643.3 (red), and 694.2 nm (far-red), respectively. In practice, the blue light hazard efficiency of radiation (BLHER) of the hybrid white light was less than 0.10, which was lower than half of the most common light sources. The η V ranged from 51.6 to 115.6 lm/W at correlated color temperature (CCT) from 2700 to 6500 K. On average, the CIE general color rendering index (Ra), CIE special color rendering index for the ninth deep red test sample (R9), ANSI/IES TM-30 color fidelity index (Rf), and color gamut index (Rg) of hybrid white light were 91.3, 87.8, 83.3, and 96.7, respectively. The melanopic efficacy of luminous radiation ( K m e l , V ) was tunable in the range of 0.60 to 1.35 mW/lm. These results demonstrated that we used far-red LEDs to fabricate white light with low BLH and relatively high efficiency. [ABSTRACT FROM AUTHOR]

Plants adopt a series of strategies to tolerate solar UV-B radiation (with the side effects of growth reduction), but the positive effects of solar UV-B radiation have not been yet clarified. In this study, two cultivars with different leaf thickness for Chestnut rose (Rosa roxburghii Tratt), a pioneering species for ecological restoration in Karst region of Southwest China, were employed to investigate its responses to ultraviolet-B (UV-B) exclusion, moderate drought, and their combination in an outdoor experiment. Thin-leaf cultivars (Gui 2) adopt an opportunistic growth strategy, growing better than Gui 7 under UV-B exclusion combined with well-watered conditions. To avoid the penetration of solar UV-B wavelengths into the underlying leaf tissues, Gui 2 exhibited higher enhancements in leaf thickness, palisade/spongy tissue ratio, antioxidant responses such as the leaf concentration of flavonols compounds catalyse activity under solar UV-B exposure. Moreover, ambient solar UV-B radiation alleviated the adverse impact caused by drought in both cultivars, improving total biomass and reducing membrane penetration. This alleviation may be related with two potential explanations. First, solar UV-B radiation primes chestnut rose plants with increased antioxidative capacity against drought stress, shown in both antioxidative enzyme activity and non-enzyme antioxidants (in particular, with total flavonols and flavonol ratio [(quercetin+myricetin)/kaempferol]). Second, to avoid nutrition insufficiency, solar UV-B radiation and drought endows chestnut rose plants with complementary effects on nutrition balance. Overall, solar UV-B radiation helps the chestnut tolerate drought stress that occurs frequently in the Karst region by modulating its antioxidative capacity and nutrition balance. [ABSTRACT FROM AUTHOR]

Septic lung damage is associated with endothelial cell and neutrophil activation. This study examines the role of the E3 ubiquitin ligase midline 1 (Mid1) in abdominal sepsis. Mid1 expression was increased in endothelial cells derived from post-capillary venules in septic mice and TNF-α challenge increased Mid1 levels in endothelial cells in vitro. The siRNA-mediated knockdown of Mid1 decreased TNF-α-induced upregulation of ICAM-1 and neutrophil adhesion to endothelial cells. Moreover, Mid1 silencing reduced leukocyte adhesion in post-capillary venules in septic lungs in vivo. The silencing of Mid1 not only decreased Mid1 expression but also attenuated expression of ICAM-1 in lungs from septic mice. Lastly, TNF-α stimulation decreased PP2Ac levels in endothelial cells in vitro, which was reversed in endothelial cells pretreated with siRNA directed against Mid1. Thus, our novel data show that Mid1 is an important regulator of ICAM-1 expression and neutrophil adhesion in vitro and septic lung injury in vivo. A possible target of Mid1 is PP2Ac in endothelial cells. Targeting the Mid1-PP2Ac axis may be a useful way to reduce pathological lung inflammation in abdominal sepsis. [ABSTRACT FROM AUTHOR]