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
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
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
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
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