5 resultados para HIGH TRANSPARENCY
em CentAUR: Central Archive University of Reading - UK
Resumo:
The levels of health-related phytochemicals were determined in lettuce leaf and in strawberry, raspberry and blueberry fruits grown in near-commercial conditions under plastic films of three different UV transparencies. In the red lettuce Lollo Rosso, total phenolics, anthocyanin, luteolin and quercetin levels were all raised by changing from a UV blocking film to a film of low UV transparency, and to a film of high UV transparency. The related green lettuce, Lollo Biondo, cultivated under the same conditions, showed virtually no phytochemical responses to the same variation in UV levels. Overall, the phenolic levels of strawberries, raspberries, and blueberries were unresponsive to the UV transparency of the plastic film under which the crops were grown. The significance of these findings is discussed in relation to the nutritional quality of soft fruit and salad crops which are increasingly being grown commercially under plastic tunnels.
Resumo:
Red leaf lettuce (Lollo Rosso) was grown under three types of plastic films that varied in transparency to UV radiation (designated as UV block, UV low, and UV window). Flavonoid composition was determined by high-performance liquid chromatography (HPLC), total phenolics by the Folin-Ciocalteu assay, and antioxiclant capacity by the oxygen radical absorbance capacity (ORAC) assay. Exposure to increased levels of UV radiation during cultivation caused the leaves to redden and increased concentrations of total phenols and the main flavonoids, quercetin and cyanidin glycosides, as well as luteolin conjugates and phenolic acids. The total phenol content increased from 1.6 mg of gallic acid equivalents (GAE)/g of fresh weight (FW) for lettuce grown under UV block film to 2.9 and 3.5 mg of GAE/g of FW for lettuce grown under the UV low and UV window films. The antioxiclant activity was also higher in lettuce exposed to higher levels of UV radiation with ORAC values of 25.4 and 55.1 mu mol of Trolox equivalents/g of FW for lettuce grown under the UV block and UV window films, respectively. The content of phenolic acids, quantified as caffeic acid, was also different, ranging from 6.2 to 11.1 mu mol/g of FW for lettuce cultivated under the lowest and highest UV exposure plastic films, respectively. Higher concentrations of the flavonoid glycosides were observed with increased exposure to UV radiation, as demonstrated by the concentrations of aglycones after hydrolysis, which were cyanidin (ranging from 165 to 793 mu g/g), quercetin (ranging from 196 to 880,mu g/g), and luteolin (ranging from 19 to 152 mu g/g). The results demonstrate the potential of the use of UV-transparent plastic as a means of increasing beneficial flavonoid content of red leaf lettuce when the crop is grown in polytunnels.
Resumo:
Red leaf lettuce (Lollo Rosso) was grown under three types of plastic films that varied in transparency to UV radiation (designated as UV block, UV low, and UV window). Flavonoid composition was determined by high-performance liquid chromatography (HPLC), total phenolics by the Folin-Ciocalteu assay, and antioxiclant capacity by the oxygen radical absorbance capacity (ORAC) assay. Exposure to increased levels of UV radiation during cultivation caused the leaves to redden and increased concentrations of total phenols and the main flavonoids, quercetin and cyanidin glycosides, as well as luteolin conjugates and phenolic acids. The total phenol content increased from 1.6 mg of gallic acid equivalents (GAE)/g of fresh weight (FW) for lettuce grown under UV block film to 2.9 and 3.5 mg of GAE/g of FW for lettuce grown under the UV low and UV window films. The antioxiclant activity was also higher in lettuce exposed to higher levels of UV radiation with ORAC values of 25.4 and 55.1 mu mol of Trolox equivalents/g of FW for lettuce grown under the UV block and UV window films, respectively. The content of phenolic acids, quantified as caffeic acid, was also different, ranging from 6.2 to 11.1 mu mol/g of FW for lettuce cultivated under the lowest and highest UV exposure plastic films, respectively. Higher concentrations of the flavonoid glycosides were observed with increased exposure to UV radiation, as demonstrated by the concentrations of aglycones after hydrolysis, which were cyanidin (ranging from 165 to 793 mu g/g), quercetin (ranging from 196 to 880,mu g/g), and luteolin (ranging from 19 to 152 mu g/g). The results demonstrate the potential of the use of UV-transparent plastic as a means of increasing beneficial flavonoid content of red leaf lettuce when the crop is grown in polytunnels.
Resumo:
This article critically examines the nature and quality of governance in community representation and civil society engagement in the context of trans-national large-scale mining, drawing on experiences in the Anosy Region of south-east Madagascar. An exploration of functional relationships between government, mining business and civil society stakeholders reveals an equivocal legitimacy of certain civil society representatives, created by state manipulation, which contributes to community disempowerment. The appointment of local government officials, rather than election, creates a hierarchy of upward dependencies and a culture where the majority of officials express similar views and political alliances. As a consequence, community resistance is suppressed. Voluntary mechanisms such as Corporate Social Responsibility (CSR) and the Extractive Industries Transparency Initiative (EITI) advocate community stakeholder engagement in decision making processes as a measure to achieve public accountability. In many developing countries, where there is a lack of transparency and high levels of corruption, the value of this engagement, however, is debatable. Findings from this study indicate that the power relationships which exist between stakeholders in the highly lucrative mining industry override efforts to achieve "good governance" through voluntary community engagement. The continuing challenge lies in identifying where the responsibility sits in order to address this power struggle to achieve fair representation.
Resumo:
In Britain, substantial cuts in police budgets alongside controversial handling of incidents such as politically sensitive enquiries, public disorder and relations with the media have recently triggered much debate about public knowledge and trust in the police. To date, however, little academic research has investigated how knowledge of police performance impacts citizens’ trust. We address this long-standing lacuna by exploring citizens’ trust before and after exposure to real performance data in the context of a British police force. The results reveal that being informed of performance data affects citizens’ trust significantly. Furthermore, direction and degree of change in trust are related to variations across the different elements of the reported performance criteria. Interestingly, the volatility of citizens’ trust is related to initial performance perceptions (such that citizens with low initial perceptions of police performance react more significantly to evidence of both good and bad performance than citizens with high initial perceptions), and citizens’ intentions to support the police do not always correlate with their cognitive and affective trust towards the police. In discussing our findings, we explore the implications of how being transparent with performance data can both hinder and be helpful in developing citizens’ trust towards a public organisation such as the police. From our study, we pose a number of ethical challenges that practitioners face when deciding what data to highlight, to whom, and for what purpose.