University of Stirling

About: University of Stirling is a education organization based out in Stirling, Stirling, United Kingdom. It is known for research contribution in the topics: Population & Context (language use). The organization has 7722 authors who have published 20549 publications receiving 732940 citations. The organization is also known as: Stirling University.

HyFlex: a benchmark framework for cross-domain heuristic search

Abstract: This paper presents HyFlex, a software framework for the development of cross-domain search methodologies. The framework features a common software interface for dealing with different combinatorial optimisation problems and provides the algorithm components that are problem specific. In this way, the algorithm designer does not require a detailed knowledge of the problem domains and thus can concentrate his/her efforts on designing adaptive general-purpose optimisation algorithms. Six hard combinatorial problems are fully implemented: maximum satisfiability, one dimensional bin packing, permutation flow shop, personnel scheduling, traveling salesman and vehicle routing. Each domain contains a varied set of instances, including real-world industrial data and an extensive set of state-of-the-art problem specific heuristics and search operators. HyFlex represents a valuable new benchmark of heuristic search generality, with which adaptive cross-domain algorithms are being easily developed and reliably compared.This article serves both as a tutorial and a as survey of the research achievements and publications so far using HyFlex.

Zebrafish cDNA Encoding Multifunctional Fatty Acid Elongase Involved in Production of Eicosapentaenoic (20:5n-3) and Docosahexaenoic (22:6n-3) Acids

Abstract: Enzymes that increase the chain length of fatty acids are essential for biosynthesis of highly unsaturated fatty acids The gLELO gene encodes a protein involved in the elongation of polyunsaturated fatty acids in the fungus Mortierella alpina A search of the GenBank database identified several expressed sequence tag sequences, including one obtained from zebrafish (Danio rerio), with high similarity to gLELO The full-length transcript ZfELO, encoding a polypeptide of 291 amino acid residues, was isolated from zebrafish liver cDNA The predicted amino acid sequence of the open reading frame shared high similarity with the elongases of Caenorhabditis elegans and human When expressed in Saccharomyces cerevisiae, the zebrafish open reading frame conferred the ability to lengthen the chain of a range of C18, C20, and C22 polyunsaturated fatty acids, indicating not only that biosynthesis of 22:6n-3 from 18:3n-3 via a 24-carbon intermediate is feasible, but also that one elongase enzyme can perform all three elongation steps required The zebrafish enzyme was also able to elongate monounsaturated and saturated fatty acids, and thus demonstrates a greater level of promiscuity in terms of substrate use than any elongase enzyme described previously

The Norse landnám on the North Atlantic islands : an environmental impact assessment.

Abstract: The Norse colonisation or landnam of the North Atlantic islands of the Faroes, Iceland, and Greenland from the ninth century AD onwards provides opportunities to examine human environmental impacts on ‘pristine’ landscapes on an environmental gradient from warmer, more maritime conditions in the east to colder, more continental conditions in the west. This paper considers key environmental contrasts across the Atlantic and initial settlement impacts on the biota and landscape. Before landnam, the modes of origin of the biota (which resulted in boreo-temperate affinities), a lack of endemic species, limited diversity, and no grazing mammals on the Faroes or Iceland, were crucial in determining environmental sensitivity to human impact and, in particular, the impact of introduced domestic animals. Gathering new data and understanding their geographical patterns and changes through time are seen as crucial when tackling fundamental questions about human interactions with the environment, which are relevant to both understanding the past and planning for the future.

Compromised Survivorship in Zoo Elephants

Abstract: We analyzed data from over 4500 elephants to show that animals in European zoos have about half the median life span of conspecifics in protected populations in range countries. This discrepancy is clearest in Asian elephants; unlike African elephants in zoos, this species' infant mortality is very high (for example, twice that seen in Burmese timber camps), and its adult survivorship in zoos has not improved significantly in recent years. One risk factor for Asian zoo elephants is being moved between institutions, with early removal from the mother tending to have additional adverse effects. Another risk factor is being born into a zoo rather than being imported from the wild, with poor adult survivorship in zoo-born Asians apparently being conferred prenatally or in early infancy. We suggest stress and/or obesity as likely causes of zoo elephants' compromised survivorship.