94 research outputs found

    Effects of human demand on conservation planning for biodiversity and ecosystem services

    Get PDF
    Safeguarding ecosystem services and biodiversity is critical to achieving sustainable development. To date, ecosystem services quantification has focused on the biophysical supply of services with less emphasis on human beneficiaries (i.e., demand). Only when both occur do ecosystems benefit people, but demand may shift ecosystem service priorities toward human-dominated landscapes that support less biodiversity. We quantified how accounting for demand affects the efficiency of conservation in capturing both human benefits and biodiversity by comparing conservation priorities identified with and without accounting for demand. We mapped supply and benefit for 3 ecosystem services (flood mitigation, crop pollination, and nature-based recreation) by adapting existing ecosystem service models to include and exclude factors representing human demand. We then identified conservation priorities for each with the conservation planning program Marxan. Particularly for flood mitigation and crop pollination, supply served as a poor proxy for benefit because demand changed the spatial distribution of ecosystem service provision. Including demand when jointly targeting biodiversity and ecosystem service increased the efficiency of conservation efforts targeting ecosystem services without reducing biodiversity outcomes. Our results highlight the importance of incorporating demand when quantifying ecosystem services for conservation planning

    LPP3 mediates self-generation of chemotactic LPA gradients by melanoma cells

    Get PDF
    Melanoma cells steer out of tumours using self-generated lysophosphatidic acid (LPA) gradients. The cells break down LPA, which is present at high levels around the tumours, creating a dynamic gradient that is low in the tumour and high outside. They then also migrate up this gradient, creating a complex and evolving outward chemotactic stimulus. Here we introduce a new assay for self-generated chemotaxis, and show that raising LPA levels causes a delay in migration rather than loss of chemotactic efficiency. Knockdown of the lipid phosphatase LPP3 - but not its homologues LPP1 or LPP2 - diminishes the cell's ability to break down LPA. This is specific for chemotactically active LPAs, such as the 18:1 and 20:4 species. Inhibition of autotaxin-mediated LPA production does not diminish outward chemotaxis, but loss of LPP3-mediated LPA breakdown blocks it. Similarly, in both 2D and 3D invasion assays, knockdown of LPP3 diminishes melanoma cells' ability to invade. Our results demonstrate that LPP3 is the key enzyme in melanoma cells' breakdown of LPA, and confirm the importance of attractant breakdown in LPA-mediated cell steering

    N-WASP control of LPAR1 trafficking establishes response to self-generated LPA gradients to promote pancreatic cancer cell metastasis

    Get PDF
    Pancreatic ductal adenocarcinoma is one of the most invasive and metastatic cancers and has a dismal 5-year survival rate. We show that N-WASP drives pancreatic cancer metastasis, with roles in both chemotaxis and matrix remodeling. lysophosphatidic acid, a signaling lipid abundant in blood and ascites fluid, is both a mitogen and chemoattractant for cancer cells. Pancreatic cancer cells break lysophosphatidic acid down as they respond to it, setting up a self-generated gradient driving tumor egress. N-WASP-depleted cells do not recognize lysophosphatidic acid gradients, leading to altered RhoA activation, decreased contractility and traction forces, and reduced metastasis. We describe a signaling loop whereby N-WASP and the endocytic adapter SNX18 promote lysophosphatidic acid-induced RhoA-mediated contractility and force generation by controlling lysophosphatidic acid receptor recycling and preventing degradation. This chemotactic loop drives collagen remodeling, tumor invasion, and metastasis and could be an important target against pancreatic cancer spread

    The Law of Society: Governance Through Contract

    Get PDF
    This paper focuses on contract law as a central field in contemporary regulatory practice. In recent years, governance by contract has emerged as the central concept in the context of domestic privatization, domestic and transnational commercial relations and law-and-development projects. Meanwhile, as a result of the neo-formalist attack on contract law, governance of contract through contract adjudication, consumer protection law and judicial intervention into private law relations has come under severe pressure. Building on early historical critique of the formalist foundations of an allegedly private law of the market, the paper assesses the current justifications for contractual governance and posits that only an expanded legal realist perspective can adequately explain the complex nature of contractual agreements in contemporary practice. The paper argues for an understanding of contracts as complex societal arrangements that visibilize and negotiate conflicting rationalities and interests. Institutionally, contractual governance has been unfolding in a complex, historically grown and ideologically continually contested regulatory field. Governance through contract, then, denotes a wide field of conflicting concepts, ideas and symbols, that are themselves deeply entrenched in theories of society, market and the state. From this perspective, we are well advised to study contracts in their socio-economic, historical and cultural context. A careful reading of scholars such as Henry Sumner Maine, Morris Cohen, Robert Hale, Karl Llewellyn, Stewart Macaulay and Ian Macneil offers a deeper understanding of the institutional and normative dimensions of contractual governance. Their analysis is particularly helpful in assessing currently ongoing shifts away from a welfare state based regulation (governance) of contractual relations. Such shifts are occurring on two levels. First, they take place against the backdrop of a neo-liberal critique of government interference into allegedly private relations. Secondly, the increasingly influential return to formalism in contract law, which privileges a functionalist, purportedly technical and autonomous design and execution of contractual agreements over the view of regulated contracts, is linked to a particular concept of sovereignty. The ensuing revival of freedom of contract occurs in remarkable neglect of the experiences of welfare state adjudication of private law adjudication and a continuing contestation of the political in private relationships. The paper takes up the Legal Realists\u27 search for the \u27basis of contract\u27, but seeks to redirect the focus from the traditional perspective on state vs. market to a disembedded understanding of contractual governance as delineating multipolar and multirational regulatory regimes. Where Globalization has led to a fragmentation, disembeddedness and transnationalization of contexts and, thus, has been challenging traditional understanding of embeddedness, the task should no longer be to try applying a largely nation-state oriented Legal Realist perspective and critique to the sphere of contemporary contractual governance, but - rather - to translate its aims into a more reflexive set of instruments of legal critique. Even if Globalization has led to a dramatic denationalization of many regulatory fields and functions, it is still not clear, whether and how Globalization replaces, complements or aggravates transformations of societal governance, with and through contract

    Molecular Evolution of Broadly Neutralizing Llama Antibodies to the CD4-Binding Site of HIV-1

    Get PDF
    To date, no immunization of humans or animals has elicited broadly neutralizing sera able to prevent HIV-1 transmission; however, elicitation of broad and potent heavy chain only antibodies (HCAb) has previously been reported in llamas. In this study, the anti-HIV immune responses in immunized llamas were studied via deep sequencing analysis using broadly neutralizing monoclonal HCAbs as a guides. Distinct neutralizing antibody lineages were identified in each animal, including two defined by novel antibodies (as variable regions called VHH) identified by robotic screening of over 6000 clones. The combined application of five VHH against viruses from clades A, B, C and CRF_AG resulted in neutralization as potent as any of the VHH individually and a predicted 100% coverage with a median IC50 of 0.17 µg/ml for the panel of 60 viruses tested. Molecular analysis of the VHH repertoires of two sets of immunized animals showed that each neutralizing lineage was only observed following immunization, demonstrating that they were elicited de novo. Our results show that immunization can induce potent and broadly neutralizing antibodies in llamas with features similar to human antibodies and provide a framework to analyze the effectiveness of immunization protocols

    Genomic insights into rapid speciation within the world’s largest tree genus Syzygium

    Get PDF
    Species radiations, despite immense phenotypic variation, can be difficult to resolve phylogenetically when genetic change poorly matches the rapidity of diversification. Genomic potential furnished by palaeopolyploidy, and relative roles for adaptation, random drift and hybridisation in the apportionment of genetic variation, remain poorly understood factors. Here, we study these aspects in a model radiation, Syzygium, the most species-rich tree genus worldwide. Genomes of 182 distinct species and 58 unidentified taxa are compared against a chromosome-level reference genome of the sea apple, Syzygium grande. We show that while Syzygium shares an ancient genome doubling event with other Myrtales, little evidence exists for recent polyploidy events. Phylogenomics confirms that Syzygium originated in Australia-New Guinea and diversified in multiple migrations, eastward to the Pacific and westward to India and Africa, in bursts of speciation visible as poorly resolved branches on phylogenies. Furthermore, some sublineages demonstrate genomic clines that recapitulate cladogenetic events, suggesting that stepwise geographic speciation, a neutral process, has been important in Syzygium diversification
    corecore