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Children all over the world suffer from atopic dermatitis (AD), a prevalent condition that impairs their health. Corticosteroids, which have long-term negative effects, are frequently used to treat AD. There has been a growing body of research on the gut microbiota's function in AD. Nevertheless, the function and underlying mechanisms of fecal microbiota transplantation (FMT) in AD children remain to be established. Therefore, in order to assess the preventive effects of FMT treatment on AD and investigate the mechanisms, we constructed an ovalbumin (OVA)-induced juvenile mouse AD model in this investigation. This study explored the role and mechanism of FMT treatment in AD through 16S RNA sequencing, pathological histological staining, molecular biology, and Flow cytometry. Results demonstrated that the FMT treatment improved the gut microbiota's diversity and composition, bringing it back to a level similar to that of a close donor. Following FMT treatment, OVA-specific antibodies were inhibited, immunoglobulin (Ig) E production was decreased, the quantity of mast cells and eosinophils was decreased, and specific inflammatory markers in the skin and serum were decreased. Further mechanistic studies revealed that FMT treatment induced CD103+ DCs and programmed cell death ligand 1 (PD-L1)/programmed cell death 1 (PD-1) expression in skin-draining lymph nodes and promoted Treg production to induce immune tolerance and suppress skin inflammation. Meanwhile, changes in the gut microbiota were substantially correlated with Th2 cytokines, OVA-specific antibodies, and PD-L1/PD-1. In conclusion, FMT regulates the Th1/Th2 immunological balance and the gut microbiota. It may also inhibit AD-induced allergy responses through the PD-L1/PD-1 pathway, and providing a unique idea and possibly a fresh approach to the treatment of AD.

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In the present work, 111 soil samples from 11 different Chinese apple plant areas were used to take the diffuse reflection spectra from 12 500 to 4 000 cm(-1) by FT-NIR. The models of organic substance and pH value of soil samples were built by using partial least square regression (PLSR). The calibration model gave the correlation coefficients of 0.818 and 0.836 for the two values respectively, with the root mean square error of prediction (RMSEP) of 0.377 (%) and 0.251, respectively. In order to improve the robustness and performance of calibration, several spectra preprocessing methods were employed, including standard normalized variate (SNV), multiplicative scatter correction (MSC) and direct orthogonal signal correction (DOSC). Finally, the performance of DOSC was found to be the best for organic substance and pH value with RMSEP of 0.258 (%) an 0.248, respectively. The results showed that the technology of NIR spectroscopy was useful to nondestructive determination of the organic substance and pH value of soil. These research findings provide theoretic base for fertilization and pomiculture by means of NIR diffuse reflection.

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Application of two statistical models to reconstruct occupational exposure to manganese (Mn) is discussed. Air monitoring of 635 samples were analyzed by a back-propagation artificial neural network (back-propagation ANN) in comparison with a multiple linear regression (MLR). The stepwise MLR yielded significant results with five selected variables for predicting airborne manganese dioxide (MnO(2)). However, a 6-12-1 back-propagation ANN was superior to the data from MLR. Statistical parameters and non-parametric paired tests indicated that back-propagation ANN represents the more useful and accurate tool. ANN was used to predict missing MnO(2) concentrations in the present study. The median of MnO(2) was 0.445 mg/m(3) (IQR 0.131-1.342). The MnO(2) characteristics of time, distance, and exposure site were defined. Airborne MnO(2) for three previous periods (1978-1988, 1989-1998, and 1998-2007) were 1.228 mg/m(3), 0.664 mg/m(3), and 0.501 mg/m(3), respectively. The medians were 0.350 mg/m(3), 0.281 mg/m(3), and 0.190 mg/m(3) at distances of 5, 10, and 25 m away from the site of exposure. Compared with levels encountered in other studies, mine concentrator sites were more seriously polluted, due to the practices of direct ore processing.

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In the present study, 22 certified milk samples without melamine were collected, then 50 adulterated milk samples with added different content of melamine (0.1-1 500 mg x kg(-1)) were prepared. The near-infrared (NIR) spectra of these milk samples were measured. The possibility of using NIR spectra to detect melamine in milk was studied. Partial least square regression (PLSR) was applied to construct the calibration model between NIR spectra and the content of melamine. The results showed that NIR spectroscopy can not accurately predict the content of melamine because of its poor detection limit. However, the combination of NIR spectra and partial least square-discriminate analysis (PLS-DA) was applied to differentiate the certified milk samples and the adulterated milk sample. The classification accuracy was 100%. Therefore, NIR spectra could be used to preliminarily detect whether the milk was adulterated with melamine. As a complementary detecting method to the high performance liquid chromatography (HPLC), NIR spectra could improve the detecting efficiency of milk

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In the present experiment, we mainly discussed the function mechanism between the humic acid and a new kind of fungicide Pyrimorph, aiming to play a positive role in the reduction of contamination caused by pesticides on environment. After the disposition step by step, the humic acid was separated into three parts. Then IR and fluorescence analytical methods were employed to explain the functional mechanism between the pesticide and each part of humic acid. As a result, there are extensive interactions between the three parts of the humic acid and the fungicide Pyrimorph. The interactions between fulvic acid and Pyrimorph are mainly the H-bond and the transfer of the electric charge caused by the C=O of the Pyrimorph and the -OH of the fulvic acid, and the interaction between matomeilon and Pyrimorph is mainly the transfer of the electric charge, and the interaction between humin and Pyrimorph is the weakest. It was showed that the fulvic acid is the most active part in the humic acid. That's to say the intensity of the interaction between the three parts of the humic acid and the fungicide Pyrimorph is smaller and smaller with the order of molecular weight from small to big, namely fulvic acid, matomeilon acid and humin.

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