975 resultados para Cucumis melo reticulatus
Resumo:
Synopsis
Objectives
To exploit the microbial ecology of bacterial metabolite production and, specifically, to: (i) evaluate the potential use of the pigments prodigiosin and violacein as additives to commercial sunscreens for protection of human skin, and (ii) determine antioxidant and antimicrobial activities (against pathogenic bacteria) for these two pigments.
Methods
Prodigiosin and violacein were used to supplement extracts of Aloe vera leaf and Cucumis sativus (cucumber) fruit which are known to have photoprotective activity, as well as some commercial sunscreen preparations. For each, sunscreen protection factors (SPFs) were determined spectrophotometrically. Assays for antimicrobial activity were carried out using 96-well plates to quantify growth inhibition of Staphylococcus aureus and Escherichia coli.
Results
For the plant extracts, SPFs were increased by an order of magnitude (i.e. up to ~3.5) and those for the commercial sunscreens increased by 10–22% (for 4% w/w violacein) and 20–65% (for 4% w/w prodigiosin). The antioxidant activities of prodigiosin and violacein were approximately 30% and 20% those of ascorbic acid (a well-characterized, potent antioxidant). Violacein inhibited S. aureus (IC506.99 ± 0.146 μM) but not E. coli, whereas prodigiosin was effective against both of these bacteria (IC50 values were 0.68 ± 0.06 μM and 0.53 ± 0.03 μM, respectively).
Conclusion
The bacterial pigments prodigiosin and violacein exhibited antioxidant and antimicrobial activities and were able to increase the SPF of commercial sunscreens as well as the extracts of the two plant species tested. These pigments have potential as ingredients for a new product range of and, indeed, represent a new paradigm for sunscreens that utilize substances of biological origin. We discussed the biotechnological potential of these bacterial metabolites for use in commercial sunscreens, and the need for studies of mammalian cells to determine safety.
Resumo:
Learning has an important position in the development of employees and their expertise. This article focuses on the role and utilization of intra and interorganizational formal and informal learning within different types of learning networks. Specifically, we investigate different types of networks (inter- or intraorganizational) and different types of learning (formal or informal) that can occur within such networks. Our qualitative case study is based on 46 expert interviews involving 49 interviewees, through which we explore how formal and informal learning was used in the development and implementation of quality improvement initiatives at a large public teaching hospital in Portugal. Our analysis suggests that formal and informal learning can take place within different types of learning networks that draw on internal resources as well as on the collaboration with external entities. The article argues that it is important for HRD managers, seeking to support organizational learning, to understand how different types of learning take place, and which features of learning networks support these processes.
Resumo:
The EU has historically been portrayed as a distinctive international actor both in terms of the norms and values it exports in context of its international relations and the manner in which it seeks to influence others. However, such claims to the EU’s distinctiveness are increasingly being questioned. This article joins this chorus of voices arguing the non-distinctiveness of the EU’s foreign policy power by focusing on a specific feature of the EU’s external trade policy, the role of World Trade Organization (WTO) dispute settlement in the EU’s attempts to promote its interests, values and norms.
Resumo:
High spectral resolution (~80 000) and signal-to-noise observations from the Ultraviolet and Visual Echelle Spectrograph Paranal Observatory Project (UVES-POP) are used to study the interstellarmolecular lines CN (3874 Å), CH+ (3957, 4232 Å) and CH (3886, 4300 Å) towards 74 O- and B-type stellar sightlines. Additionally, archive data are presented for 140 ELODIE early-type stellar sightlines at R = 42 000, plus 25 FEROS at R = 48 000 and 3 UVES at R > 50 000, mainly in the CH+ (4232 Å) and CH (3886, 4300 Å) transitions. Detection rates are ~45 per cent for CN and ~67 per cent for the other lines in the POP sample, and ~10-15 per cent for CH+ and CH lines in the additional sample. CH and CH+ are well correlated between log[N(CH) cm-2]~12-14, implying that these clouds are CH+-like CH and not CN-like CH. CH is also very well correlated with Na I D in the range log[N(Na I cm-2]) ~12.2-14.2. A few sightlines show tentative velocity shifts of ~2 km s-1 between CH and CH+, which appear to be caused by differences in component strength in blends, and hence do not provide firm evidence for shocks. Finally, we describe a search for 13CH+ in a sightline towards HD 76341. No 13CH+ is detected, placing a limit on the 13CH+ to 12CH+ ratio of ~0.01. If a formal fit is attempted, the equivalent width ratio in the two isotopes is a factor ~90 but with large errors.
Resumo:
Providing the first comprehensive examination of the key regulatory disciplines included in the new generation of EU free trade agreements (FTAs), this book investigates the EU's supposed deep trade agenda through a legal analysis of these FTAs. In doing so, Billy A. Melo Araujo determines whether there is any substance behind the EU's foreign policy rhetoric regarding the need to introduce regulatory issues within the remit of international trade law.
At a time when the EU is busily negotiating so-called 'mega-FTAs', such as the Transatlantic Trade and Investment Partnership (TTIP) and the plurilateral Trade in Services Agreement (TISA), Melo Araujo offers a timely insight into the important questions raised by such FTAs, in particular concerning the future of the multilateral trade system, the loss of policy autonomy, and the democratic legitimacy of regulating through treaty-making. The book provides a detailed analysis of the regulatory disciplines included in the more recent EU FTAs and explores the possible implications of such disciplines. Offering a significant contribution to a wider debate, this is a must read for those interested in the legal dimension of the EU's deep trade agenda.