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Thermal history modeling based on low-temperature thermochronological data is widely used in the study of geology. Despite its common applications, several problems remain easy to ignore yet should not be overlooked in the execution of such models. This paper describes four key problems of thermal history modeling, namely, (1) is the best-fit thermal history the best? (2) Is the date constraint box a suitable constraint? (3) Does the bimodal distribution of the apatite fission track confined track length absolutely correspond to the cooling reheating model? (4) Is the whole thermal history path credible? Counterexamples are then provided to stress the importance of accounting for these problems in the application of thermal history modeling. Acknowledging the uncertainty and considering the geological constraints are recommended to improve the accuracy of thermal history models. Moreover, thermal historical intervals with high credibility and strong constraint ability are recommended to interpret the selected geological phenomenon. [ABSTRACT FROM AUTHOR]

Migmatites record crucial information about the rheology and tectonothermal evolutionof the deep crust during orogenesis. In the Wuyi–Yunkai orogen in South China, migmatites at Fuhuling record Early Paleozoic high temperatures and associated partial melting. However, the absolute timing and implications for the rheology of the deep crust during orogenesis are poorly constrained. In this contribution, we used spatial analysis of migmatitic leucosomes, structural analysis, and U-Pb geochronology of zircon to elucidate the absolute timing of crustal partial melting, the degree of partial melting, and the role of partial melting on the rheology of the crust during the Wuyi–Yunkai orogeny. Partial melting of the Fuhuling migmatites occurred at c. 440 Ma during Early Paleozoic Wuyi–Yunkai orogenesis. Subsequent lower temperature metamorphism associated with Indosinian movement that caused minor zircon recrystallization was temporally associated with the crystallization of nearby biotite monzogranites, but it did not influence the morphology of the Fuhuling migmatites. The migmatites preserve a morphological transition from metatexite to diatexite with an increasing proportion of leucosome. This transition preserves different structural characteristics that represent the response of the solid framework and melt network to variable melt fractions during partial melting. The large proportion of in situ or in source leucosome in the Fuhuling migmatites suggests that it was a melt-rich crustal horizon during orogenesis, and that a substantial proportion of anatectic melt was retained in the deep crust. The rheological transition documented in the Fuhuling migmatites was caused by changes in the melt fraction, and it is an analogue for the rheological transition characteristics of melt-rich crustal horizons in the Yunkai region during Early Paleozoic Wuyi–Yunkai orogenesis and subsequent orogenic collapse. [ABSTRACT FROM AUTHOR]

Objective To investigate the changes of N 6 -methyladenosine (m 6 A) modification in the inflammatory status of HIEC-6 human intestinal epithelial cells and MODE-K mouse intestinal epithelial cells. Methods HIEC-6 cells and MODE-K cells were induced by different concentrations of lipopolysaccharide (LPS), interleukin-1β (IL-1β), IL-6 and tumor necrosis factor alpha (TNF-α) for 10 hours or the same concentration of LPS, IL-1β, IL-6 and TNF-α for 0, 3, 6, 12, 24 hours, respectively. The mRNA expression levels of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were detected by real-time quantitative PCR. The mRNA and protein expression levels of m 6 A modification-related molecules methyltransferase-like 3 (METTL3), METTL14, METTL16, Wilm's tumor 1-associated protein (WTAP), alkylation repair homolog protein 5 (ALKBH5), fat-mass and obesity-associated protein (FTO), YTH domain-containing 1 (YTHDC1), YTHDC2 were detected through real-time quantitative PCR and Western blot, respectively. Results The mRNA expression levels of IL-1β, IL-6 and TNF-α were increased and the mRNA and protein expression levels of METTL3 and METTL14 were simultaneously up-regulated in time-dependent and concentration-dependent LPS-induced model in HIEC-6 cells and MODE-K cells. Conclusion LPS can induce inflammation and up-regulate the expression of METTL3 and METTL14 in intestinal epithelial cells.