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This work catalogued oligonucleotide sequences and sequence compositions based on the overall yield of full-length product obtained by the phosphoramidite chemistry-based solid phase synthesis. In total, 76 sequences with different dinucleotide and trinucleotide repeats were synthesized, and the fully-deprotected products were analyzed by denaturing anion exchange HPLC. Overall, sequences containing more 2'-deoxyadenosine residues were obtained in relatively lower yields, likely due to the relative ease of 2'-deoxyadenosine to undergo depurination during the detritylation reaction. Furthermore, dinucleotide steps, such as d(CG)/d(GC) and d(AG)/d(GA), likely contribute the overall lower yields of full-length products as well. [ABSTRACT FROM AUTHOR]

Salt weathering is considered as one of the most damaging processes acting on cultural heritage sites and salt crystallization significantly contributes to the deterioration of natural sandstone in grotto relics. A laboratory partial immersion experiment was carried out to elucidate how humidity influences the salt‐induced weathering in grotto relics. Field environmental observations at the Yungang Grottoes were conducted to evaluate the differences between experimental endeavours and field observations. Superficial salt accumulation was characterized by hydro‐chemical and quantitative atomistic analysis. It revealed the co‐existence of calcium sulphate and magnesium sulphate, with a Ca/Mg molar ratio of 0.27 at RHam and 4.13–18.15 at a constant RH. An average increase of 165 mg/L in Na+ concentration and 120.7 mg/L in Mg2+ concentration in the groundwater was detected after immersion, which was attributed to the dissolution of the sandstone rock. The reduction of 322.5 mg/L in the SO42− concentration in the groundwater after partial immersion shows that capillary forces influence the migration of SO42− from the immersion solution. Calcium sulphate and magnesium sulphate accumulation with a Ca/Mg molar ratio of 0.03–0.17 in the field environment is strongly correlated with the occurrence of salt efflorescence. The upward transport of soluble salt was driven by capillary forces after partial immersion in the groundwater collected from the Yungang Grottoes. It then migrated from the interior to the exterior of the sandstone specimen due to evaporation. Salt efflorescence formed on the upper exposed stone close to the capillary fringe owing to the combined effects of condensation, hygroscopicity and evaporation. These processes were driven by wetting–drying and dissolution–crystallization cycles in response to fluctuating environmental conditions. These results contribute to a better understanding the mechanism of salt‐induced weathering and provide a basis for future conservation to mitigate the harmful impact of salts in heritage sites. [ABSTRACT FROM AUTHOR]

Abstract Background Trichinellosis, caused by Trichinella spiralis, is a serious foodborne parasitic zoonosis. Tibetan pig is an infrequent, endemic plateau pig species, mainly distributed in Tibet Plateau, China. Because of the free-range system, Tibetan pigs are at risk of infection with Trichinella. The present study aimed to primarily profile the characteristics of T. spiralis infection in Tibetan pigs, including IgG levels, larvae burdens, and cytokines. Results The immune responses to Chinese Tibet T. spiralis isolate infection in Tibetan pigs with different doses were investigated in a tracking duration of 49 days. The muscle larvae per gram (lpg) were evaluated at 105 days post-infection (dpi). The results showed that the mean larval number of T. spiralis in Tibetan pigs increased with infective dose, with average lpg values of 3.5, 50.4 and 115.6 for Tibetan pigs infected with 200, 2,000, and 20,000 muscle larvae (ML) of T. spiralis. The anti-Trichinella IgG increased with inoculum dose and dpi, and peaked at 49 dpi. The kinetics of cytokines in the sera was detected by microarray, including interferon-γ (IFN-γ), interleukin (IL)-1β, IL-8, IL-12, IL-4, IL-6, IL-10, Granulocyte-macrophage Colony Stimulating Factor (GM-CSF), tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-β1. The Th1/Th2 mixed cytokines were detectable in all samples. Interleukin-12 demonstrated the highest concentration compared to other cytokines and peaked at 42 dpi. Almost all cytokines were maintained at a high level at 42 dpi. Additionally, we also report a Trichinella seropositive rate of 43.9 % (18 out of 41) from field samples of Tibetan pigs. Conclusions The present study showed an increased Th1/Th2 mixed cytokines in Tibetan pigs elicited by T. spiralis. The high seroprevalence of Trichinella infection in field samples of Tibetan pigs further raises serious concern for the prevention and control of trichinellosis in this host for public health safety.

This article explores the selection of solvents for the detritylation reaction in the solid-phase synthesis of oligonucleotides. The authors evaluate various solvents based on their ability to remove the DMTr group, their stability under detritylation conditions, and their potential binding to acid. The findings suggest that dichloromethane, acetonitrile, and THF are suitable solvents, while toluene and ethyl acetate may not be ideal. The article also discusses the chemical shifts observed in NMR analysis when solvents are mixed with trichloroacetic acid. The study emphasizes the importance of choosing the right solvent for successful oligonucleotide synthesis. [Extracted from the article]