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101.
The effects of CO2 enrichment on the growth and glucosinolate (GS) concentrations in the bolting stem of Chinese kale (Brassica alboglabra L.) treated with three nitrogen (N) concentrations (5, 10, and 20 mmol/L) were investigated. Height, stem thickness, and dry weights of the total aerial parts, bolting stems, and roots, as well as the root to shoot ratio, significantly increased as CO2 concentration was elevated from 350 to 800 μl/L at each N concentration. In the edible part of the bolting stem, 11 individual GSs were identified, including 7 aliphatic and 4 indolyl GSs. GS concentration was affected by the elevated CO2 concentration, N concentration, and CO2×N interaction. At 5 and 10 mmol N/L, the concentrations of aliphatic GSs and total GSs significantly increased, whereas those of indolyl GSs were not affected, by elevated atmospheric CO2. However, at 20 mmol N/L, elevated CO2 had no significant effects on the concentrations of total GSs and total indolyl GSs, but the concentrations of total aliphatic GSs significantly increased. Moreover, the bolting stem carbon (C) content increased, whereas the N and sulfur (S) contents decreased under elevated CO2 concentration in the three N treatments, resulting in changes in the C/N and N/S ratios. Also the C/N ratio is not a reliable predictor of change of GS concentration, while the changes in N and S contents and the N/S ratio at the elevated CO2 concentration may influence the GS concentration in Chinese kale bolting stems. The results demonstrate that high nitrogen supply is beneficial for the growth of Chinese kale, but not for the GS concentration in bolting stems, under elevated CO2 condition. Project (No. 2007CB109305) supported by the National Basic Research Program (973) of China  相似文献   
102.
We estimate the effectiveness of policy incentives for adoption of electric vehicles (EVs) in the 50 U.S. states. We employ a rich dataset of semi-annual state-level new EV vehicle registrations by make and model from 2010 to 2015 and state-level policy instruments that could affect new EV model registrations. We construct two measures of policy, one which aggregates policy instruments that can be assigned a value and a second that aggregates those without explicit values. Using a within model difference-in-difference estimator with high-dimensional fixed effects, we find that a $1000 increase in the value of a state’s model-specific EV policies increases registrations of that model within the state by 5–11%.  相似文献   
103.
This study is aimed at an assessment of the properties of two polymeric products applied to Norway spruce (Picea abies) and White poplar (Populus alba) wood species. It contributes to ongoing research experiments on the consolidating properties of two synthetic resins and their potential synergic action on wood, resulting from their different interaction with the substrate: Paraloid B72 and Regalrez 1126. Experiments were carried out on a series of samples of the two wood varieties. The consolidants were applied alone and one after the other, with one coat of Regalrez and then one of Paraloid. Porosity and variations in pore size distribution were ascertained by mercury intrusion porosimetry (MIP). Colorimetric and IR spectroscopic measurements were also taken before and after aging by solar radiation and freeze/thaw cycles, to verify the possible slowing of photodegradation of the treated wood and the consolidating resistance. Results confirm that both products penetrate the wood with a different behaviour. After double treatment with Regalrez + Paraloid, a significant advantage was observed in terms of mechanical resistance and pore size distribution, although no advantages as regards resistance to photo-oxidizing processes or colour changes were observed.  相似文献   
104.
Telenovelas have been considered the predominant popular genre on television, the most widely available and popular national medium, in Brazil, for more than 30 years (Straubhaar, 1982). However, we argue in this article that although telenovelas do indeed have this remarkable penetration and popularity in Brazil, their reception is mediated by audience class, geographical location, race, and issues with media content. Many in the audience feel disenfranchised from the dominant telenovela representations, particularly on the primary network, TV Globo, because of their rural, Northeastern status and identity, or their Afro-Brazilian identity. They question their sense of belonging, not because they do not feel Brazilian, but because the “Brazil” they see on TV does not include them.  相似文献   
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本文认为意识形态是一个具有现实关怀立场的批判性理论范畴,伊格尔顿也正是继承了意识形态的这种特点。他在文学和美学领域进行理论研究的同时坚持关怀现实,力图揭示意识形态生产的文学背后的社会权力关系以及审美作为一种意识形态现象的各种复杂机制。这为文学批评和研究带来两点重要的启示。  相似文献   
108.
文章对早期卫拉特人①的萨满教信仰,以及藏传佛教在卫拉特民间传播的时间、过程、内外因素进行了分析,认为卫拉特蒙古人宗教信仰的转换经历了一段艰难而复杂的过程,最终形成了卫拉特蒙古化的藏传佛教这一宗教信仰.  相似文献   
109.
汉语并列复句根据关联词语分为平列、对比、解证三种情况,大多用互相呼应 的关联词语(也有单用的),还有不用关联词语的,是通过语义和逻辑关系来体现的;而藏语表示并列关系的复句大多单用关联词语,互相呼应的关联词极少,藏语表示并列关系的关联语有表示纯语法意义的属格助词、连词、少数副词以及具格助词或副词与一些虚化的实词组合而成的连词等。翻译时根据汉藏并列复句的特点,在译文中要使用恰当的关联词语,汉语中无关联词语的,在译文中要增译相应的关联词语。  相似文献   
110.
Purpose: Considering current debates on ecosystem services’ effectiveness and the AIS/AKIS functioning, in this study we suggest a new, systemic way to evaluate extension systems (ESs). Using this model, we compared the effectiveness of ESs in three countries with essential differences but also characteristic similarities in their agricultural sectors: Greece, Italy and Slovenia.

Design/methodology/approach: Initially, we defined ‘extension system’ as a wide range of actors integrating resources with the aim of co-producing value (not for but with) farmers. To capture the value flow within this constellation of actors we distinguished between the notion of ‘value in production’ – i.e. the value embodied in service offerings – and the value emanating when service content is used in real settings or ‘value in use.’

Findings: Our approach revealed that, despite their structural and organizational differences, the ES in the three countries share common problems arising from a limited focus on the issue of value in use.

Practical implications: The application of a systemic approach – seeing farmers as co-creators and not as end-users of extension services – in the evaluation of ESs contributes to better understand the complexity of value flow within the system and can strengthen extension systems’ effectiveness.

Theoretical implications: The present study, by reconsidering traditional evaluation approaches and by focusing on value co-production, offers an alternative value-centric framework for the conceptualization of extension services and points out to the need for refining the evaluation criteria of ESs.

Originality/value: Our work, by emphasizing the reciprocal creation of value within ESs, and by adding the concept of value in use, offers a new systems approach worth considering when evaluating ESs within different organizational and sociocultural contexts.  相似文献   

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