[Responses of soil moisture and photosynthetic characteristics to mulching materials and ridge-to-furrow ratios in rapeseed fields in southwest dryland of China]. / è¥¿å—æ—±åœ°æ²¹èœç”°åœŸå£¤æ°´åˆ†å’Œä½œç‰©å ‰åˆç‰¹å¾å¯¹è¦†ç›–ææ–™å’Œåž„æ²Ÿæ¯”çš„å“åº”.

In order to deal with the frequent seasonal drought and improve water use efficiency and crop photosynthetic efficiency in drylands of southwest China, a field experiment was conducted to investigate the effects of different mulching materials (common white film, common black film, biodegradable film and no film) and ridge-to-furrow ratios (40 cm:40 cm and 40 cm:80 cm) on soil water storage, as well as photosynthetic characteristics, fluorescence parameters and chlorophyll relative content (SPAD) of rapeseed, with the flat planting as the control. The results showed that the average soil water storage under different mulching materials followed the order: ridge with common black film (BR) ≈ ridge with common white film (WR) ≈ ridge with biodegradable film (BDR) ＞ ridge with no film (NR) ＞ flat planting (FP). Meanwhile, ridge-to-furrow ratios did not affect soil water storage. The net photosynthetic rate, stomatal conductance and fluorescence para-meters (Fm, Fv, Fv/Fm, Fv/Fo, qP and qN) of rapeseed under ridge-furrow with film mulching was higher than those under flat planting. Compared with control, SPAD value was improved by 6.1%, 8.6%, 8.5% and 3.6% under WR, BR, BDR and NR, while instantaneous water use efficiency (IWUE) was increased by 18.3%, 11.4%, 16.3% and 10.4% under those treatments, respectively. Rapeseed yield under BR, WR and BDR was significantly higher than that in control, while NR did not increase yield. The treatment of ridge with common black film + 40 cm:40 cm as ridge-to-furrow ratio could gain the highest economic benefit. Ridge-furrow planting of rainfall harvesting could improve soil moisture, increase crop photosynthetic capacity, and raise yield and economic income in rapeseed fields in drylands of southwest China.

Isolation and characterisation of N-benzyl tadalafil as a novel adulterant in a coffee-based dietary supplement.

A new tadalafil analogue was detected via high-performance liquid chromatography (HPLC)-diode array detection (DAD) during routine screening of health foods suspected of adulteration with erectile dysfunction drugs. The UV absorption spectrum of the unknown was almost identical to that of tadalafil. The analogue was purified by preparative HPLC and structural elucidation carried out by mass spectrometric and NMR spectroscopic experiments. The spectral data revealed that this tadalafil analogue bears a benzyl group instead of the methyl group. The isolated compound was identified as N-benzyl tadalafil. Considering the risk it poses to public health, this new PDE-5 analogues for ED should be included on the inspection list for illegal products.

[Discussion on evaluation mode of proficiency testing for heavy metal and harmful element detection in medicines].

This study aims to explore the evaluation model for the proficiency testing of heavy metal and harmful element residues in pharmaceuticals,and to provide reference for the proficiency testing program and proficiency testing result in the field of residue analysis. The proficiency test result of cadmium determination in honeysuckle as an example. The algorithm A,NIQR,and Horwitz function are used to calculate the assigned value and the standard deviation. Z was obtained at the same time. If | Z | ≤2,the result is satisfactory. If 2< | Z | <3,the result is questionable. If | Z | ≥3,the result is unsatisfactory. In addition,the median value is the assigned value,and deviation(D%) is used. If D% is not more than 16%,the result is satisfactory; if D% is more than 16%,the result is unsatisfactory. After analysis,in the results of questionable or dissatisfied laboratories calculated by algorithm A and NIQR,the deviation error of some data is within the scope of the standard. In the results of the satisfactory laboratory evaluated by the Horwitz function,some data deviation errors far exceed the standard range. The evaluation result of the D% meets the requirements. According to heavy metal and harmful element trace analysis methods,this study is the first to apply D% to the evaluation of the detection ability of heavy metals and harmful elements in pharmaceuticals. This method makes the evaluation result more reasonable,and has important reference significance for the evaluation of other proficiency test results.