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An empirical equation has been proposed to describe geochemical backgrounds of trace elements during rock weathering on weathering and lithological indices. However, with respect to lithium, the equation was derived on only 9 regolith profiles in China and was not applicable to carbonate-bearing materials with WIG (weathering index of granite) larger than 120. To derive a robust and widely used equation on geochemical backgrounds of lithium, 851 elemental abundance data including 379, 280, and 192 records of rocks, soils, and stream sediments, respectively, were used to fit the new equation. lg c = −0.02630 xy 2 z + 0.03000 xyz 2 + 0.03540 xy + 0.6425 y + 3.288 for WIG<20 （1） lg c = 0.00001579 x 2 yz + 0.001141 y 2 xz - 0.9445 y + 0.3650 z for 20≤WIG<120 （2） lg c = 0.1849 xy 2 z + 0.03382 xyz 2 + 0.6839 xyz - 09414 x - 1.471 y + 1.070 z for WIG≥120 （3） where c is the calculated geochemical background of Li in μg/g. WIG is the weathering index of granite. The x in Eq. (1) and Eq. (2) is WIG and is lg(WIG) in Eq. (3). The y is lg(Al 2 O 3 /Ti) where Al 2 O 3 and Ti represent their contents with units of wt% and μg/g respectively. The z is lg(K 2 O/SiO 2) where K 2 O and SiO 2 represent their contents in wt%. The fitting data of Li, WIG, Al 2 O 3 /Ti, and K 2 O/SiO 2 are 3.5–70 μg/g, 6.9–9400, 0.0003–0.0356, and 0.0006–0.1410, respectively. By comparison with the previous equation in a linear fitting, the newly presented equation in a nonlinear fitting is applicable to geological materials without WIG limitations. However, to the materials with WIG ranging from 0 to 120, the fitted results between the previous and the newly presented equations are generally similar. In summary, the new equation works well to describe lithium geochemical backgrounds of geological materials and could play an important role in environmental and exploration geochemistry. In mineral exploration, the method of seven levels' classification of geochemical anomaly can be improved on this newly presented equation and has been validated in the Tieshanlong tungsten deposit area in Southeastern China. • A new equation on 851 elemental abundances was proposed using the partial derivative quadratic function theory to describe Li geochemical backgrounds. • The new equation is applicable to samples in the rock-soil-sediment systems. • The new equation is potential in environmental and exploration geochemistry. [ABSTRACT FROM AUTHOR]

Abstract: Genetic variation and structure of four natural populations of Paramichelia baillonii (Pierre) Hu (family Magnoliaceae) from China were assessed using random amplified polymorphic DNA (RAPD) markers and morphological characters. For RAPD analysis, 17 primers generated a total of 152 discernible and reproducible bands across the four populations analyzed, out of which 63 (41.4%) were polymorphic. The Shannon''s index (H o) varied with population, ranging from 0.555 to 1.121, with an average value of 0.955. The mean diversity at species level was H sp =1.217. Most of the genetic variation was found within population although pair-wise Φ ST values and Bartlett''s test indicated significant differentiation among populations. The between-population component comprised 21.1% and 15.7% of the total genetic variation, respectively, as assessed by the Shannon''s index and AMOVA analysis. The gene flow (N m) ranged from a moderate value of 0.464 (between populations YL and YE) to a high value of 4.128 (between populations YP and YE), with an average value of 1.570. The results for P. baillonii are generally in accordance with those already recorded for other outcrossing tropical tree species. For morphological characters, principal component analysis showed that the first two components explained a total of 77.6% of the whole phenotypic variability, but a dispersion plot of all the families defined by the first two principal components did not show any significant grouping. The overall population differentiation index in quantitative traits (Q ST) is 0.07 and less than that at RAPD markers (Φ ST, 0.157). The pair-wise Q ST estimates are significantly correlated with pair-wise Φ ST (r =0.8643, P =0.0264) while the correlation between the Euclidean distance matrices based on morphological and RAPD data was low and non-significant (r =−0.0189, P =0.3103). The information obtained here could be valuable for devising strategies for conservation and domestication of P. baillonii. [Copyright &y& Elsevier]

To sustain an ecological and economical textile industry, the development of a simple coloring process, featuring characteristics of both minimum pollutant discharge and versatile for natural and synthetic fibers, remains a challenging task. Herein, a simple (only containing coloring and curing process) and recycled pigment foam coloring approach for cotton, silk and polyester is designed, which is based on photoresponsive foams formed by a nonionic azobenzene surfactant (NAS) doping into a pigment foam coloring system containing sodium dodecyl sulfate (SDS), pigment dispersion and binder. Detailed investigations of photoisomerization of NAS , foam properties and color parameters of the obtained fabrics in the recycled pigment foam coloring system are presented. In the pigment foam coloring system, NAS maintains highly selective and reversible photoisomerization properties, allowing to generate colored photoresponsive foams with high photochemical fatigue resistance. With a tunable stability controlled by light, the stable colored foams can be applied in the coloring process for cotton, silk and polyester, while the rapid breakage of residual foams triggered by UV-light enables the recycling of residual foams for further re-utilization at the end of the coloring process, providing a simple alternative coloring process for natural and synthetic fibers with nearly-zero pollutant discharge. This could open up a promising strategy to improve the ecological and economic efficiency of textile coloring industry. Image 1 • A nonionic azobenzene surfactant has been designed to prepare photoresponsive foams. • The stability of colored foams can be remotely controlled solely by light. • The process is feasible in coloring cotton, silk and polyester fabrics. • Residual foams are recyclable, enabling the process to be nearly-zero pollutant discharge. [ABSTRACT FROM AUTHOR]

Abstract Oxygenated polycyclic aromatic hydrocarbons (OPAHs) are a class of anthropogenic, persistent and very toxic PAH contaminant associated with developmental toxicity. Abnormal glucose metabolism disturbs energy balances that impair the early development of vertebrates, but the mechanisms by which maternal OPAH exposure alters glucose homeostasis in offspring are not well understood. Studies have suggested that epigenetic changes, particularly in DNA methylation, provide a memory of plastic developmental responses to the environment, leading to the generation of novel offspring phenotypes. The objective of this study is to test the hypothesis that embryonic exposure to low-dose OPAH can impair early β-cell differentiation in zebrafish (Danio rerio) by altering DNA methylation and gene expression. The zebrafish embryos were exposed to 0, 0.03, 0.1, 0.3, 1 and 3 μM 9‑fluorenone (9-FLO) at 3 h postfertilization (hpf) until 120 hpf to assess pancreatic organogenesis. 9-FLO exposure reduced total body length, eye length and heart rate, decreased insulin generation, interfered with glucose metabolism, and altered the expression of pancreatic organogenesis-related genes pdx-1, foxa2, isl1 and ptf1a. In particular, low-dose embryonic 9-FLO exposure significantly decreased β-cell differentiation marker gene pdx-1 mRNA levels, indicating that pancreatic endocrine is a more sensitive target response to embryonic low-dose OPAH exposure. Additionally, we found that DNA methyltransferases dnmt1 and dnmt3 were elevated and the DNA methylation at promoter regions of pdx-1 was increased at an early stage of development. These data demonstrated that the low-dose OPAH embryonic exposure can impair pancreatic endocrine development by increasing DNA methylation at the promoter regions of pdx-1 that are essential for β-cell differentiation. Graphical abstract Unlabelled Image Highlights • The endocrine pancreas is a sensitive target tissue of developmental exposure to low-dose OPAH. • OPAH embryonic exposure alters expression of pancreas-specific-related genes. • Low-dose OPAH exposure results in inhibition of β-cell differentiation. • Low-dose OPAH exposure increased promoter DNA methylation of pdx-1. [ABSTRACT FROM AUTHOR]

• The average secretion level of MT in Tibetan sheep blood was highest occurred during diestrus and the lowest during proestrus. In addition, the secretion level of MT at night was significantly higher than that at day. • This study found that MTNR1A was distributed in all tissues of HPGA during the estrous cycle in Tibetan sheep, and there were significant differences in the expression of MTNR1A in various tissues. • This study found that there were also significant differences in the expression of MTNR1A mRNA in HPGA during oestrus cycle in Tibetan sheep. • The differences in MT secretion pattern and the expression of MTNR1A in HPGA suggest that they may be affected by steroid hormone secretion during the estrous cycle of Tibetan sheep. The melatonin 1A receptor (MTNR1A) is a membrane receptor distributed across the mammalian gonadal axis-associated membrane. Melatonin (MT) can specifically bind with MTNR1A on the cell membrane and regulates mammalian reproductive activities. However, the role of MTNR1A in regulating the reproductive physiological activities of sheep in the Tibetan Plateau remains unclear. In this study, the MT content in Tibetan sheep blood during the estrous cycle was detected by ELISA. The distribution of MTNR1A in the hypothalamus-pituitary–gonadal axis (HPGA) was analyzed by immunohistochemistry and immunofluorescence. Western blot and qRT-PCR were used to detect dynamic changes of MTNR1A mRNA and protein expression, and the protein distributions in the HPGA. The results showed that the average secretion level of MT in Tibetan sheep blood was highest occurred during diestrus and the lowest during proestrus. Additionally, the secretion of MT at night was significantly higher than during the day. The immunopositive products of MTNR1A were primarily distributed around the glial cells in the dorsal hypothalamic nucleus region, chromophobe cells, and eosinophilic cytoplasm in the pituitary gland, follicular granular layer, follicular adventitia, tubal mucosa, cilia, endometrium, interstices, and glands in the uterus. The expression trends of MTNR1A mRNA and proteins in the HPGA during the estrous cycle were the same. The relative expression levels of MTNR1A mRNA and proteins in the hypothalamus and ovaries were the highest during proestrus and the lowest during metestrus; the highest during diestrus in the pituitary and oviducts; the highest during metestrus in the uterus. Collectively, the differences in the secretion of MT in Tibetan sheep blood and the expression of MTNR1A in HPGA suggest that they may be affected by steroid hormone secretion during the estrous cycle of Tibetan sheep, which has a potential impact on the regulation of animal estrous cycle. [ABSTRACT FROM AUTHOR]