ALBERT

Description: In this study (S)-3-hydroxyacyl-CoA dehydrogenase/enoyl-CoA hydratase (H16_A0461/FadB’, gene ID: 4247876) from one of two active fatty acid degradation operons of Ralstonia eutropha H16 has been heterologously expressed in Escherichia coli, purified as protein possessing a His-Tag and initially characterized. FadB’ is an enzyme with two catalytic domains exhibiting a single monomeric structure and possessing a molecular weight of 86 kDa. The C-terminal part of the enzyme harbors enoyl-CoA hydratase activity and is able to convert trans-crotonyl-CoA to 3-hydroxybutyryl-CoA. The N-terminal part of FadB’ comprises an NAD+ binding site and is responsible for 3-hydroxyacyl-CoA dehydrogenase activity converting (S)-3-hydroxybutyryl-CoA to acetoacetyl-CoA. Enoyl-CoA hydratase activity was detected spectrophotometrically with trans-crotonyl-CoA. (S)-3-Hydroxyacyl-CoA dehydrogenase activity was measured in both directions with acetoacetyl-CoA and 3-hydroxybutyryl-CoA. FadB’ was found to be strictly stereospecific to (S)-3-hydroxybutyryl-CoA and to prefer NAD+. The K m value for acetoacetyl-CoA was 48 μM and V max 149 μmol mg−1 min−1. NADP(H) was utilized at a rate of less than 10% in comparison to activity with NAD(H). FadB’ exhibited optimal activity at pH 6–7 and the activity decreased at alkaline and acidic pH values. Acetyl-CoA, propionyl-CoA and CoA were found to have an inhibitory effect on FadB’. This study is a first report on biochemical properties of purified (S)-stereospecific 3-hydroxyacyl-CoA dehydrogenase/enoyl-CoA hydratase with the inverted domain order from R. eutropha H16. In addition to fundamental information about FadB’ and fatty acid metabolism, FadB’ might be also interesting for biotechnological applications.

Description: Species introduction, combined with changing access rules, increasing demand, and new road and dam infrastructure, are contributing to remarkable changes in Bolivian Amazon fisheries. This paper examines community responses to the appearance of a commercially valuable introduced fish species, Arapaima cf. gigas (“paiche”) in the Bolivian Amazon. Until the end of the 20th century, fisheries in this region were relatively low intensity, focused in rivers on a small number of native large-sized species by an urban-based commercial fishing fleet, and in floodplain lakes on a high diversity of native medium-sized species for subsistence by rural indigenous communities. In the seventies, Arapaima cf. gigas was introduced from Peru and has since invaded a significant portion of the Madre de Dios and Beni basins in northern Bolivia. This species now represents up to 80 % of commercial catches for the region. Occupying primarily floodplain lakes, many of which are located within indigenous territories, it has created economic opportunities and stimulated conflicts. The evolution of fisheries in one indigenous Tacana community is described, and the perspectives of local fishers are explored. Results suggest that while the new resource has strengthened incipient community-level organization, the current capture strategies and management mechanisms may not be conducive to sustainability or equitable distribution of returns. Commercial fisheries targeting a set of native species have been replaced by a single-species fishery in this community, raising questions about how the changes both in the resource-base and associated livelihood strategies are impacting system resilience. Ecosystem impacts of the introduction remain unclear. Paiche is viewed both as a potential threat and an opportunity by indigenous fishers. The management of this introduced species for a maximum social benefit and minimal environmental damage are topical concerns for communities and government actors and should be treated carefully considering local and broader, regional-scale implications.

Description: Background: For the development of a sustainable energy system, the public’s contribution to the sustainment of the system’s current operations will become vital. The public’s role is expected to change from that of passive service abiders to active service providers, as anticipated by visions of prosumers, smart grids, demand side management, virtual power plants, and electric vehicle management. Smart technology and new business models will increase system complexity and the experience of uncertainty and risk for all parties. Actionability of the public’s participation in the opportunities arising from the transformation of energy systems will become a problem. Methods: With a qualitative functionalist method, we analyze the prerequisites of the public’s participation: the capacity of social mechanisms, such as trust, for the solution of social problems. Functional problems affect the continuation of communication, i.e., the possibility of the sustainment of social reality. We isolate three case studies that illustrate concrete effects of trust, distrust, and confidence on three parties, respectively: consumers, investors, and those affected by grid extensions.Results and conclusionsWe argue that the social mechanisms of trust and confidence are more vital for consumers, investors, and those affected than previous research has noticed. These mechanisms determine the achievement of sustainability in energy systems by sustaining actionability as a favorable expectation (trust, confidence), or an unfavorable expectation (lack of trust, distrust). Even lack of trust and distrust can be valuable contributors on the road to sustainability, since they uncover flaws and setbacks of a fledgling smart grid.

Description: In this paper, we consider α- ( ψ , ϕ ) contractive mappings in the setting of quasi-partial metric spaces and verify the existence of a fixed point on such spaces. Moreover, we present some examples and applications in integral equations of our obtained results.MSC: 46T99, 46N40, 47H10, 54H25.

Description: We use the gauge function introduced by Fang to gain a fixed point result in probabilistic G-metric spaces. Our work extends some existing results. Moreover, our result is supported with an example.MSC: 47H10, 54H25.

Description: #betterconnected—a perspective on social media Content Type Journal Article Category Building a Professional Career Pages 1-3 DOI 10.1007/s00216-011-5633-8 Authors Sara Shinton, Shinton Consulting Ltd., Galashiels, Selkirkshire, UK Journal Analytical and Bioanalytical Chemistry Online ISSN 1618-2650 Print ISSN 1618-2642