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Waste Pisha sandstone (WPS) is the main damming material for the check dam in the Loss Plateau of northwest China. The dissolution characteristics of WPS in alkaline solutions were investigated as a basis for studying WPS modification materials and revealing the modification mechanism to further study the pozzolanic activity of WPS and the development of cementitious materials for concrete utilizing WPS. In this paper, WPS was milled and calcined at 600 °C, 700 °C, and 800 °C, respectively. After that, the activated WPS was immersed in 0.05, 0.1, 0.5, 1.0, 2.0, and 5.0 M NaOH solutions for leaching tests. The two curing temperatures of 20 °C and 80 °C were set, respectively. The ion concentration of Si, Al, and Ca in the alkaline solutions was determined using chemical titration, silicon–molybdenum blue colorimetric method, and graphite furnace atomic absorption spectrometry, respectively. After the leaching tests, the residues of WPS were characterized using XRD and SEM-EDS. The results show that the concentration of each ion in the leachate did not increase with leaching time but showed fluctuating variations with leaching time. Mechanochemical activation and thermal activation will promote the dissolution of minerals in alkaline solutions and increase the leaching efficiency of Si. However, the soluble Si in the leachate is not able to generate further gelling-like substances, limited by the total amount of available Ca in the mineral. WPS can dissolve more ions in higher concentrations of a NaOH solution, but the mineral crystallinity of its residue will be reduced. Higher curing temperatures can greatly increase the leaching efficiency of Si in a short time, which is better than thermal activation, and it can also promote the generation of newborn minerals and increase the crystallinity of minerals in WPS after leaching. [ABSTRACT FROM AUTHOR]

Airport ferry vehicles are used to transport passengers between the far apron and terminals. During the peak hours of flight arrival or departure, the demand for ferry vehicles will increase, and improper scheduling will result in significant delays. In this study, we construct a 0–1 integer programming scheduling model for ferry vehicles with multiple objectives: minimize flight delays and vehicle travel distances and balance vehicle workloads when there is an insufficient number of ferry vehicles. To solve the multiobjective model, this study selects the second version of the nondominated sorting genetic algorithm-II as the main framework and designs a modified coding and decoding scheme to solve the constraint problem in the model. The proposed model and algorithm are verified using actual data from Kunming Changshui International Airport, China. Compared with the scheduling method of manual first come first serve, the total delay time of the proposed model is reduced by 24.52%, the transit distance by 6.63%, and the balance index by 24.05%, which helps the airport solve the problem of insufficient ferry vehicles during peak hours. Comparison results show that the proposed model has a shorter calculation time and better distribution of solution sets than three state-of-the-art multiobjective optimization algorithms: MOPSO, MOACO, and SPEA-II. This research can help airports reduce flight delays, vehicle purchases, and operation costs. [ABSTRACT FROM AUTHOR]

• The frequency distribution of a missense mutation (NC_037347.1: c.1543A > G, p.ser515gly) in the SLC45A2 gene is consistent with the distribution of climatic conditions in China. • Association analysis showed this site is closely related environmental indicators. SLC45A2 is involved in the synthesis of melanin transporters. We investigated the association between single nucleotide polymorphisms (SNPs) of the SLC45A2 gene and humidity and hot conditions in indigenous cattle habitat. According to the Bovine Genome Variation Database and Selective Signatures (BGVD), we explored the frequency distribution of a missense mutation (NC_037347.1: c.1543A > G, p.ser515gly) in the SLC45A2 gene in Chinese indigenous cattle. This variation from serine to glycine caused a significant change in the protein modeling structure. PCR and partial DNA sequencing were used to genotype 541 individuals, including 28 Chinese indigenous cattle breeds as well as Angus and zebu. From our results, the mutant allele frequency of this SNP in Chinese native cattle increases gradually from north to south, which is consistent with the distribution of climatic conditions in China. In addition, according to association analysis of a missense mutation (NC_037347.1: c.1543A > G) (rs525805167) in Chinese cattle, it is closely related to the annual average temperature (T), relative humidity (RH), temperature and humidity index (THI) and solar radiation time (P < 0.01). Based on the statistical analysis of the data, we assumed that rs525805167 was associated with heat tolerance traits. Simple Summary: The characteristics of Chinese indigenous cattle are closely related to their climatic environment. In China, Bos taurus is mainly distributed in the northern regions; Bos indicus is mainly distributed in southern China. In addition, the average temperature is higher in the south than in the north, and there are many mixed ancestry breeds of B. taurus and B. indicus in the middle area. The SLC45A2 gene is related to melanin synthesis, which may be closely related to heat tolerance in cattle. The purpose of our study was to investigate whether the SLC45A2 gene is related to heat tolerance in Chinese indigenous cattle. [ABSTRACT FROM AUTHOR]

The photocatalytic property of Fe oxide minerals has long been considered to play an important role in shaping modern terrestrial environments. However, due to the complexity of natural settings, a precise determination of the band structure of natural goethite has not been achieved. In this work, the mineralogical characteristics of natural goethite samples obtained from Zhushan, China, were systematically studied through X-ray diffraction, transmission electron microscopy, X-ray energy dispersive spectroscopy, and X-ray fluorescence spectroscopy. Afterward, the band structure for both natural and synthetic goethite samples was determined by synchrotron-based X-ray absorption and emission spectra and photoelectron spectroscopy. The band gap of natural goethite (2.25 eV) was narrower than that of its synthetic counterpart (2.55 eV), and the valence band position of natural goethite was slightly lifted (−5.06 eV) compared to that of synthetic goethite (−5.38 eV). Al doping in natural goethite crystal, as revealed by the mineralogical tests, was the main reason that contributed to this difference. The theoretical calculation showed the narrowed band gap was caused by the contribution of Al-2p orbits at the top of the valence band. Therefore, free electrons can be created under light irradiation with a shorter wavelength. The experiments showed that natural goethite can photo-catalytically degrade methyl orange, and the degradation efficiency was better (47.5%) than that of the synthetic goethite group (31.5%). This study, for the first time, revealed the band structure and confirmed the photocatalytic properties of natural goethite, which should play an important role in surface substance evolution and elemental cycling. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To analyze the safety of combined leflunomide (LEF), methotrexate (MTX), and glucocorticoid (GC) therapy, we investigated the adverse effects of such combination therapy in patients with early active rheumatoid arthritis (RA). Methods: Two hundred sixty-six patients with RA who were receiving LEF and MTX therapy were randomly assigned to 3 groups, as follows: group 1 received no GC, group 2 received 7.5 mg prednisone, and group 3 received 15 mg prednisone. Adverse effects were analyzed using the χ2 test at week 4 or the Fisher exact test at week 12. Results: Patients in group 1 had a higher incidence of skin rash, oral ulcers, leukopenia, and liver damage than did those in groups 2 and 3 (all, P ≤ 0.05). However, the rates of osteoporosis, diabetes, hyperlipidemia, and hypertension in group 3 were statistically higher than in groups 1 and 2 (P ≤ 0.05). Conclusion: In the treatment of RA, the incidence of skin rash, liver dysfunction, and oral ulcers may be decreased with combination therapy using LEF, MTX, and 7.5 mg prednisone, and blood pressure, blood glucose concentration, and bone density are not increased. Most important, 7.5 mg prednisone was synergistic with LEF and MTX, and such combination therapy could be a useful option as initial treatment of early active RA. [Copyright &y& Elsevier]

To reveal the effects of nitrogen (N) inputs and mowing on the abundance and richness of insect community in meadow steppe, we investigated the abundance and diversity of herbivorous insects under four treatments in Inner Mongolia meadow steppe in August 2022, including control, N addition, mowing, and combined N addition and mowing. At a long-term control experimental platform, we collected insects using the vacuum sampling method. The results showed that N addition significantly increased the abundance of herbivorous insects, and mowing significantly decreased the abundance of herbivorous insects. Nitrogen addition significantly increased insect abundance in unmown condition but not in the mown condition. The responses of insect abundance at the community level to N addition were mainly driven by the dominant groups, Cicadellidae and Lygaeidae, which was affected by the abundance of Gramineae species. In contrast, their responses to mowing were the opposite. Both N addition and mowing did not affect the diversity of herbivorous insects. Our results indicated that the responses of herbivorous insect abundance to N inputs and mowing were directly regulated by food resources. With increasing food resource availability, the abundance but not the diversity of herbivorous insects increased, with stronger responses of dominant groups than subordinate ones.

Potassium (K) is the second most abundant nutrient in plant leaves after nitrogen (N) and the most abundant cation in plant cells. It plays an important role in plant growth regulation, homeostasis maintenance, and stress response. Previous studies on the effects of N input on plant nutrient status mainly focus on N and phosphorus (P), but less on K and its stoichiometry. We examined the effects of N input and mowing on K content and N:K at both plant functional group and community levels. We analyzed the relative contribution of changes in functional groups and community composition to changes of community level nutrition status. The results showed that N input increased N content of each plant functional group and increased K content of rhizomatous grasses and legumes. Mowing reduced N content of rhizomatous grasses and bunchgrass, but did not affect K content and N:K of all functional groups. Nitrogen input significantly increased plant N and K contents at the community level, while mowing significantly increased plant N content. Both N input and mowing did not affect plant N:K at functional group and community levels. The contribution of nutritional changes in plant functional groups to the variation at the community level was greater than that of changes in community composition. For all the three examined nutritional traits, the contribution of nutrients at functional group level and that of community composition showed negative covariation. Our results indicated that plant N:K had high homeostasis in meadow steppe and that plants could regulate N and K balance, which was of great significance for maintaining N:K stoichiometry under the background of increasing N deposition.

Natural colloids (NCs) are ubiquities in aquatic environments, which play an important role in the fate and transport of metal elements. Combined with a multi-method analytical approach, this study investigates the spectral characteristics and the contamination of metals of NCs from the five tributaries of Poyang Lake and the lakes in Nanchang City. Results showed that NCs in river samples were characteristic by the smaller molecular weight, lower chromophoric dissolved organic matter (CDOM) concentration, higher aromaticity, and higher CDOM contribution to the organic carbon than those in lake samples. Based on the parallel factor analysis model, three fluorophores were identified, including two humic-like components (C1 and C2) and a protein-like component (C3). NCs in river and lake waters were dominant by the humic-like substance (C1) and the protein-like substance (C3), respectively, with the relatively high fluorescence intensity for all the fluorophores in lake samples. Furthermore, NCs from the river samples were primarily terrestrial NCs with a high degree of humification. The average detection frequency of metal elements was nearly 50% for both river and lake samples, whereas the concentrations of the metal elements were higher in lake samples. Principal component analysis (PCA) results showed that the contamination of the detected metals could divide into three categories, with relatively high concentrations of Ba, Pb, Zn, Al, Sr, and Fe in lake samples. Moreover, PCA results showed that NCs in lakes with higher values of the absorbance and fluorescence parameters were associated with the higher concentration of metal elements, revealing that the spectral characteristic could be the proxy indicator of the contamination of metal elements of NCs.