Assessing nitrate leaching during the three‐first years of Miscanthus × giganteus from on‐farm measurements and modeling

Miscanthus × giganteus is often regarded as one of the most promising crops to produce sustainable bioenergy. This perennial crop, renowned for its high productivity associated with low input requirements, in particular regarding fertilizers, is thought to have low environmental impacts, but few data are available to confirm this. Our study aimed at assessing nitrate leaching from Miscanthus × giganteus crops in farmers' fields, thus including a wide range of soil and cropping system conditions. We focused on the first years of growth after planting as experimental studies have suggested that Miscanthus × giganteus, once established, results in low nitrate leaching. We combined on‐farm measurements and modeling to estimate drainage, leached nitrogen, and nitrate concentration in drainage water in 38 fields located in Center‐East France during two winters (November 2010 to March 2011, November 2011 to March 2012). Nitrate leaching and nitrate concentration in drainage water were on average very low. Nitrate leaching averaged 6 kg N ha^?1 whereas nitrate concentration averaged 12 mg l^?1. These low values are attributable to the low estimates of drainage water (mean = 166 mm) but also to the low soil mineral nitrogen contents measured at the beginning of winter (mean = 37 kg N ha^?1). Our results were, however, very variable, mainly due to the crop age: nitrate leaching and nitrate concentration were critically higher during the winter following the first growth year of Miscanthus × giganteus, reflecting the low development of the crop. This variability was also explained by the range of soil and cropping conditions explored in the on‐farm design: shallow and/or sandy soils as well as fields where establishment failed had a higher risk of nitrate leaching.     

大头茶属植物研究进展

大头茶属(Polyspora Sweet)为山茶科常绿树木,共50种,主要分布于南亚和东南亚地区。大头茶属植物均具有较高观赏价值,可作为热带和亚热带地区的园林绿化树种,部分种类兼具食用和药用价值。该文在对大头茶属种质资源和应用情况简要介绍的基础上,对其系统演化及分类、繁殖特征、生理特性、生态习性、育苗技术、化学成分及药理活性等方面的研究进展进行了较为详细的综述,提出了目前研究中存在的问题,并对今后的研究方向进行了展望,指出未来应扩大大头茶属的研究范围和种类,加强种质资源搜集、系统发育、遗传多样性等研究,重点关注大头茶属的引种栽培与种质创新,充分发掘其药用价值,开展临床转化和药物研制工作,可为合理开发利用野生大头茶属种质资源提供理论依据和研究思路。     

Studying the effects of virtual biodiversity research infrastructures

The research environment of scholars is increasingly web-based. This makes it urgent to study the effects of moving to the Web on research practices, scholarly output and innovation. We propose a theoretical framework and a methodology to study these effects. In a pilot study, we apply theory and method on an online community in biodiversity research, to demonstrate the feasibility of the approach. We also indicate the practical relevance of this kind of analysis for improving the quality of virtual research environments. In the last section, directions for further research are suggested.     

中医经络的光子学研究

在中医经络现代研究的基础上,探讨光子学在经脉循行路线的客观检测,循经感传现象的发生及其实质意义,经络腧穴诊断的客观化以及腧穴双向良性调节作用等研究领域的具体应用.指出中医经络的光子学研究有望借助光子学的学科优势,从科学的角度对我国经络学说进行诠释和量化,为经脉腧穴的光学特性提供重要的实验依据,并有望找到一种非侵人性、无...     

Shortening tobacco life cycle accelerates functional gene identification in genomic research

Definitive allocation of function requires the introduction of genetic mutations and analysis of their phenotypic consequences. Novel, rapid and convenient techniques or materials are very important and useful to accelerate gene identification in functional genomics research. Here, over‐expression of PmFT (Prunus mume), a novel FT orthologue, and PtFT (Populus tremula) lead to shortening of the tobacco life cycle. A series of novel short life cycle stable tobacco lines (30–50 days) were developed through repeated self‐crossing selection breeding. Based on the second transformation via a gusA reporter gene, the promoter from BpFULL1 in silver birch (Betula pendula) and the gene (CPC) from Arabidopsis thaliana were effectively tested using short life cycle tobacco lines. Comparative analysis among wild type, short life cycle tobacco and Arabidopsis transformation system verified that it is optional to accelerate functional gene studies by shortening host plant material life cycle, at least in these short life cycle tobacco lines. The results verified that the novel short life cycle transgenic tobacco lines not only combine the advantages of economic nursery requirements and a simple transformation system, but also provide a robust, effective and stable host system to accelerate gene analysis. Thus, shortening tobacco life cycle strategy is feasible to accelerate heterologous or homologous functional gene identification in genomic research.     

Health care professionals' perspectives on oral care for long-term care residents: nursing staff, speech-language pathologists and dental hygienists

doi: 10.1111/j.1741‐2358.2011.00513.x Health care professionals’ perspectives on oral care for long‐term care residents: Nursing staff, speech–language pathologists and dental hygienists Background: Oral health has been identified as a key factor in general health and systemic disease in long‐term care populations. To optimise oral health of this population, it is important to understand the oral care perspectives held by health care professionals involved in oral care provision. Objectives: To explore perspectives regarding oral care held by nursing staff, speech–language pathologists (SLPs) and dental hygienists (DHs) in long‐term care institutions and to understand how their perspectives impact activities and processes involved in the delivery of oral care. Methods: A focus group methodology was utilised. Separate focus groups for each targeted profession were held. Transcribed data were analysed using constant comparative analysis. Results: Daily oral health maintenance and monitoring was considered a role of nursing staff. SLPs and DHs have roles focusing on advocacy, education and supplemental care. Social factors motivate nursing staff to provide oral care, whereas factors related to the general health consequences of poor oral health underlined the motivations of SLPs and DHs. Conclusions: Education and training initiatives incorporating social aspects of oral health may be more effective for motivating nursing staff than approaches emphasising physical risk factors. Organisations can foster environments that support collaboration and communication amongst the members of multidisciplinary teams in order to promote oral health as a priority.     

邂逅幻化碧波的斑斓遐思——剪影夏威夷第17届世界生物毒素大会

第17届世界生物毒素大会不久前在美国夏威夷如期召开。本文针对这次大会上热议的“生物恐怖”、充分张扬的从医学→毒素→医学的学科发展态势以及生物毒素与靶通道受体“矛与盾”的分子解构等学术关注热点和推进亮点做一简介。     

科研与旅游

科研与旅游在一些方面是相似,乃至相通的。科研是在浩瀚知识海洋中的旅游。具体地说,均有准备、过程和总结三个阶段。最精彩的是其过程。科研与旅游的精髓是发现和享受。享受旅游,享受科研,享受生活,享受人生。