XPS and FTIR studies of fungus-stained Daemonorops margaritae

We explored the discoloration of rattan cane using X-ray photoelectron spectroscopy(XPS) and Fourier transform infrared spectroscopy(FTIR). XPS analysis showed that after the cane was stained by Lasiodiplodia theobromae, carbon and oxygen elements and the ratio of oxygen to carbon decreased. Considering atomic binding,C_1 and C_4 contents increased, while C_2 and C_3 contents decreased, and the ratio of O_2 to O_1 decreased sharply. The relative contents of lignin, cellulose and polysaccharides increased and new substances with low O_2/O_1 ratio occurred. FTIR analysis showed that the absorption peaks of O–H at 3346 cm^(-1), aliphatic C–H at 2921, 2853 and1464 cm^(-1), and C=O at 1723 cm^(-1), were characteristic peaks of fungal melanin intensified, indicating that cane discoloration was primarily caused by fungal melanin. The absorption peaks characterizing cellulose and lignin like polysaccharides at 800 cm^(-1), C–H at 1374 cm^(-1), C–O at1058 and 1038 cm^(-1), phenolic hydroxyl at 1245 cm^(-1),aromatic ether bonds at 1270 cm^(-1), carbon skeleton at1608 cm^(-1) and benzene ring at 1500 cm^(-1) were enhanced since the fungus mainly consumed the extractives in cane cell lumens and the main composition content increased relatively. Regardless of the discoloration caused by natural fungi or inoculated fungi, the discoloring feature and composition changes were identical except that the fungusinoculated cane had more melanin.

Disease-specific protein corona formed in pathological intestine enhances the oral absorption of nanoparticles

Protein corona(PC)has been identified to impede the transportation of intravenously injected nanoparticles(NPs)from blood circulation to their targeted sites.However,how intestinal PC(IPC)affects the delivery of orally administered NPs are still needed to be elucidated.Here,we found that IPC exerted“positive effect”or“negative effect”depending on different pathological conditions in the gastrointestinal tract.We prepared polystyrene nanoparticles(PS)adsorbed with different IPC derived from the intestinal tract of healthy,diabetic,and colitis rats(H-IPC@PS,D-IPC@PS,C-IPC@PS).Proteomics analysis revealed that,compared with healthy IPC,the two disease-specific IPC consisted of a higher proportion of proteins that were closely correlated with transepithelial transport across the intestine.Consequently,both D-IPC@PS and C-IPC@PS mainly exploited the recycling endosome and ER-Golgi mediated secretory routes for intracellular trafficking,which increased the transcytosis from the epithelium.Together,disease-specific IPC endowed NPs with higher intestinal absorption.D-IPC@PS posed“positive effect”on intestinal absorption into blood circulation for diabetic therapy.Conversely,CIPC@PS had“negative effect”on colitis treatment because of unfavorable absorption in the intestine before arriving colon.These results imply that different or even opposite strategies to modulate the disease-specific IPC need to be adopted for oral nanomedicine in the treatment of variable diseases.

Irregular distribution of wind power prediction

Wind power is volatile and uncertain, which makes it difficult to establish an accurate prediction model.How to quantitatively describe the distribution of wind power output is the focus of this paper. First, it is assumed that wind speed is a random variable that satisfies the normal distribution. Secondly, based on the nonlinear relationship between wind speed and wind power, the distribution model of wind power prediction is established from the viewpoint of the physical mechanism. The proposed model successfully shows the complex characteristics of the wind power prediction distribution. The results show that the distribution of wind power prediction varies significantly with the point forecast of the wind speed.