Herein, we designed and constructed a dual functional surface with antimicrobial and antifouling abilities to prevent protein and bacterial attachment that are significant challenges in biomedical devices. Primary amino-group-capped sulfobetaine of DMMSA was synthesized and then grafted onto polydopamine pretreated PET sheets via click chemistry. The sheets were subsequently immersed into silver ion solution, in which the absorbed silver ions were reduced to silver nanoparticles (AgNPs) in situ by a polydopamine layer. The antifouling assays demonstrated that the resultant PET/DMMSA/AgNPs sheets exhibited great antifouling performances against bovine serum albumin (BSA), bovine fibrinogen (BFG), platelets, and bacteria, the critical proteins/microorganisms leading to implant failure. The antibacterial data suggested that the sheets had dual functions as inhibitors of bacterial growth and bactericide and could efficiently delay the biofilm formation. This repelling and killing approach is green and simple, with potential biomedical applications.

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Improving the carbon efficiency of crop production is one of the important ways to realize the low-carbon agriculture. In order to get a clear understanding of carbon efficiency in agricultural production, this paper, based on the investigation data of the farmer's production, applying input and output calculation method, evaluated the carbon input, carbon output and carbon efficiency in production of the three major crops, winter wheat, summer maize and cotton, in Wuqiao County of Hebei Province in North China Plain. The results were as follows: the carbon input of winter wheat, summer maize and cotton was 943.47±225.14, 525.74±134.73, and 513.60±138.94 kg CE ha −1 , of which fertilizers and electricity accounted for a majority, about 60% and 25% respectively. The carbon output of the three major crops was 8 430.70±774.45, 7 194.50±754.58, and 5 486.00±547.69 kg CE ha −1 respectively, of which straw accounted for 50%, economic yield accounted for 34%, and root accounted for 17%. The carbon production efficiency of winter wheat, summer maize and cotton was 7.95±2.55, 15.90±4.34, and 7.60±2.92 kg kg −1 CE, respectively. The carbon economic efficiency of the three crops was 13.28±4.56, 21.47±5.86, and 76.70±29.45 CHY kg −1 CE, respectively. The carbon ecological efficiency of the three crops was 9.59±3.07, 14.57±3.98, and 11.69±4.49 kg C kg −1 CE, respectively. There were significant differences in the carbon efficiency of the three major crops. Preliminary results showed that the carbon integrated efficiency of summer maize was the highest, followed by cotton, which in turn had higher the efficiency than winter wheat in North China Plain.

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Jujube (Ziziphus jujube Mill.) is a traditional economic forest crop and is widely cultivated in hilly areas of the Loess Plateau, China. However, soil desiccation was discovered in jujube plantations. Pruning is recognized as a water-saving method that can reduces soil water consumption. In this study, we monitored the jujube plots with control (CK), light (C 1), medium (C 2) and high (C 3) pruning intensities during the jujube growing period of 2012-2015 to explore the effect of pruning intensity on soil moisture and water use efficiency (WUE) of jujube plantations in the hilly Loess Plateau Region. The results showed that pruning is an effective method for soil water conservation in jujube plantations. Soil moisture increased with increasing pruning intensity during the jujube growing period of 2012-2015. C 1 , C 2 and C 3 pruning intensities increased soil water storage by 6.1-18.3, 14.4-40.0 and 24.3-63.3 mm, respectively, compared to CK pruning intensity. Pruning promoted soil moisture infiltration to deeper soil layer. Soil moisture infiltrated to soil depths of 240, 280 and >300 cm under C 3 pruning intensity, 220, 260 and 260 cm under C 2 pruning intensity, 200, 240 and 220 cm under C 1 pruning intensity, and 180, 200 and 160 cm under CK pruning intensity in 2013, 2014 and 2015, respectively. Soil water deficit was alleviated by higher pruning intensity. In 2013-2015, soil water change was positive under C 2 (6.4 mm) and C 3 (26.8 mm) pruning intensities but negative under C 1 (-20.5 mm) and CK (-40.6 mm) pruning intensities. Moreover, pruning significantly improved fresh fruit yield and WUE of jujube plants. Fresh fruit yields were highest under C 1 pruning intensity with the values of 6897.1-13,059.3 kg/hm 2 , which were 2758.4-4712.8, 385.7-1432.1 and 802.8-2331.5 kg/hm 2 higher than those under CK, C 2, and C 3 pruning intensities during the jujube growing period of 2012-2015, respectively. However, C 3 pruning intensity had the highest WUE values of 2.92-3.13 kg/m 3 , which were 1.6-2.0, 1.1-1.2 and 1.0-1.1 times greater than those under CK, C 1 and C 2 pruning intensities, respectively. Therefore, C 3 pruning intensity is recommended to jujube plantations for its economic and ecological benefits. These results provide an alternative strategy to mitigate soil desiccation in jujube plantations in the hilly Loess Plateau Region, which is critical for sustainable cultivation of economic forest trees in this region.