Community-based Adaptation: Lessons from the Development Marketplace 2009 on Adaptation to Climate Change

The Development Marketplace 2009 focused on adaptation to climate change. This paper identifies lessons from the Marketplace and assesses their implications for adaptation support. Our findings are based on: statistical tabulation of all proposals; in-depth qualitative and quantitative analysis of the 346 semi-finalists; and interviews with finalists and assessors. Proposals were fuelled by deep concerns that ongoing climate change and its impacts undermine development and exacerbate poverty, migration and food insecurity. Proposals addressed both local poverty and climate change challenges, and offered a wide range of approaches to render local development more resilient to current climate variability. Therefore, support to community-based adaptation should: exploit its strong local grounding and synergies with development; help connect local initiatives to higher levels; and use complementary approaches to address policy issues.Community-based Adaptation, Development Marketplace, Adaptation, Climate Change

Three cocluded insect viruses : a biophysical and biological study of the nuclear-polyhedrosis virus of Colias electo, the granulosis virus of Heliothis armigera and the nuclear-polyhedrosis virus of Heliothis zea

An investigation was undertaken in some detail of three virus strains of insect pests of agricultural importance, viz. a nuclear-polyhedrosis virus of the lucerne caterpillar, Colias electo, and a granulosis virus of the bollworm, Heliothis armigera, both found in South Africa, and a nuclear-polyhedrosis virus of the bollworm, Heliothis zea, isolated in America, with a view to ascertaining a knowledge of some of the fundamental properties and basic biology of these infective agents. On the basis of the information gained the viruses could be differentiated and their broad classification was established. The morphology of the polyhedra, capsules and virus particles observed by light and electron microscopy has been completed and measurements of the viral elements have been made. Some biophysical properties of the virus particles and their inclusion bodies were recorded, i.e. their resistance to chemical and physical treatments and their relative mobility in an electric field under standard conditions. Observations were made on procedures which brought about varying degrees of purification and concentration of the virus particles from putrefying larvae and the most successful of these were found to be reproducible. They involved the purification of the inclusion bodies and their digestion by weak alkali to release the virus particles. Both preparations of the viral elements were further purified by zone electrophoresis in sucrose density gradients. Some information was gathered on the mode of transmission of the infection from insect to insect by contact or cannibalism, from one generation to the next through the eggs, and particularly from one area to another by virus survival in avian faeces. The incidence and rate of the infection in the larvae was increased by environmental changes such as raising the temperature and also to some extent by spraying with a suspension of endospores of Bacillus thuringiensis. Exposure to other stress conditions was not successful in initiating a fatal infection in the insects. Of particular interest, however, was the observation that by injecting a 'foreign' virus a fatal infection was induced by activation of a native occult virus in the larvae of the silkworm, Bornbyx mori. In the context of the possible application of these infective agents to future methods of biological control of economically disastrous pests, these preliminary experiments were not unrewarding

Molecular pharmacology of VEGF-A isoforms: binding and signalling at VEGFR2

Vascular endothelial growth factor-A (VEGF-A) is a key mediator of angiogenesis, signalling via the class IV tyrosine kinase receptor family of VEGF Receptors (VEGFRs). Although VEGF-A ligands bind to both VEGFR1 and VEGFR2, they primarily signal via VEGFR2 leading to endothelial cell proliferation, survival, migration and vascular permeability. Distinct VEGF-A isoforms result from alternative splicing of the Vegfa gene at exon 8, resulting in VEGFxxxa or VEGFxxxb isoforms. Alternative splicing events at exons 5–7, in addition to recently identified posttranslational read-through events, produce VEGF-A isoforms that differ in their bioavailability and interaction with the co-receptor Neuropilin-1. This review explores the molecular pharmacology of VEGF-A isoforms at VEGFR2 in respect to ligand binding and downstream signalling. To understand how VEGF-A isoforms have distinct signalling despite similar affinities for VEGFR2, this review re-evaluates the typical classification of these isoforms relative to the prototypical, “pro-angiogenic” VEGF165a. We also examine the molecular mechanisms underpinning the regulation of VEGF-A isoform signalling and the importance of interactions with other membrane and extracellular matrix proteins. As approved therapeutics targeting the VEGF-A/VEGFR signalling axis largely lack long-term efficacy, understanding these isoform-specific mechanisms could aid future drug discovery efforts targeting VEGF receptor pharmacology. View Full-Tex

Fire management strategies to maintain species population processes in a fragmented landscape of fire-interval extremes

Changed fire regimes have led to declines of fire-regime- adapted species and loss of biodiversity globally. Fire affects population processes of growth, reproduction, and dispersal in different ways, but there is little guidance about the best fire regime(s) to maintain species population processes in fire-prone ecosystems. We use a process-based approach to determine the best range of fire intervals for keystone plant species in a highly modified Mediterranean ecosystem in southwestern Australia where current fire regimes vary. In highly fragmented areas, fires are few due to limited ignitions and active suppression of wildfire on private land, while in highly connected protected areas fires are frequent and extensive. Using matrix population models, we predict population growth of seven Banksia species under different environmental conditions and patch connectivity, and evaluate the sensitivity of species survival to different fire management strategies and burning intervals. We discover that contrasting, complementary patterns of species life-histories with time since fire result in no single best fire regime. All strategies result in the local patch extinction of at least one species. A small number of burning strategies secure complementary species sets depending on connectivity and post-fire growing conditions. A strategy of no fire always leads to fewer species persisting than prescribed fire or random wildfire, while too-frequent or too-rare burning regimes lead to the possible local extinction of all species. In low landscape connectivity, we find a smaller range of suitable fire intervals, and strategies of prescribed or random burning result in a lower number of species with positive growth rates after 100 years on average compared with burning high connectivity patches. Prescribed fire may reduce or increase extinction risk when applied in combination with wildfire depending on patch connectivity. Poor growing conditions result in a significantly reduced number of species exhibiting positive growth rates after 100 years of management. By exploring the consequences of managing fire, we are able to identify which species are likely to disappear under a given fire regime. Identifying the appropriate complementarity of fire intervals, and their species-specific as well as community-level consequences, is crucial to reduce local extinctions of species in fragmented fire-prone landscapes

Population dynamics of species-rich ecosystems: the mixture of matrix population models approach

Matrix population models are widely used to predict population dynamics, but when applied to species-rich ecosystems with many rare species, the small population sample sizes hinder a good fit of species-specific models. This issue can be overcome by assigning species to groups to increase the size of the calibration data sets. However, the species classification is often disconnected from the matrix modelling and from the estimation of matrix parameters, thus bringing species groups that may not be optimal with respect to the predicted community dynamics. We proposed here a method that jointly classified species into groups and fit the matrix models in an integrated way. The model was a special case of mixture with unknown number of components and was cast in a Bayesian framework. An MCMC algorithm was developed to infer the unknown parameters: the number of groups, the group of each species and the dynamics parameters. We applied the method to simulated data and showed that the algorithm efficiently recovered the model parameters. We applied the method to a data set from a tropical rain forest in French Guiana. The mixture matrix model classified tree species into well-differentiated groups with clear ecological interpretations. It also accurately predicted the forest dynamics over the 16-year observation period. Our model and algorithm can straightforwardly be adapted to any type of matrix model, using the life cycle diagram. It can be used as an unsupervised classification technique to group species with similar population dynamics. (Résumé d'auteur

A peptide derived from TIMP-3 inhibits multiple angiogenic growth factor receptors and tumour growth and inflammatory arthritis in mice

The binding of vascular endothelial growth factor (VEGF) to VEGF receptor-2 (VEGFR-2) on the surface of vascular endothelial cells stimulates many steps in the angiogenic pathway. Inhibition of this interaction is proving of value in moderating the neovascularization accompanying age-related macular degeneration and in the treatment of cancer. Tissue inhibitor of metalloproteinases-3 (TIMP-3) has been shown to be a natural VEGFR-2 specific antagonist—an activity that is independent of its ability to inhibit metalloproteinases. In this investigation we localize this activity to the C-terminal domain of the TIMP-3 molecule and characterize a short peptide, corresponding to part of this domain, that not only inhibits all three VEGF-family receptors, but also fibroblast growth factor and platelet-derived growth factor receptors. This multiple-receptor inhibition may explain why the peptide was also seen to be a powerful inhibitor of tumour growth and also a partial inhibitor of arthritic joint inflammation in vivo

Heparan sulfate proteoglycans: structure, protein interactions and cell signaling

Heparan sulfate proteoglycans are ubiquitously found at the cell surface and extracellular matrix in all the animal species. This review will focus on the structural characteristics of the heparan sulfate proteoglycans related to protein interactions leading to cell signaling. The heparan sulfate chains due to their vast structural diversity are able to bind and interact with a wide variety of proteins, such as growth factors, chemokines, morphogens, extracellular matrix components, enzymes, among others. There is a specificity directing the interactions of heparan sulfates and target proteins, regarding both the fine structure of the polysaccharide chain as well precise protein motifs. Heparan sulfates play a role in cellular signaling either as receptor or co-receptor for different ligands, and the activation of downstream pathways is related to phosphorylation of different cytosolic proteins either directly or involving cytoskeleton interactions leading to gene regulation. The role of the heparan sulfate proteoglycans in cellular signaling and endocytic uptake pathways is also discussed.Proteoglicanos de heparam sulfato são encontrados tanto superfície celular quanto na matriz extracelular em todas as espécies animais. Esta revisão tem enfoque nas características estruturais dos proteoglicanos de heparam sulfato e nas interações destes proteoglicanos com proteínas que levam à sinalização celular. As cadeias de heparam sulfato, devido a sua variedade estrutural, são capazes de se ligar e interagir com ampla gama de proteínas, como fatores de crescimento, quimiocinas, morfógenos, componentes da matriz extracelular, enzimas, entreoutros. Existe uma especificidade estrutural que direciona as interações dos heparam sulfatos e proteínas alvo. Esta especificidade está relacionada com a estrutura da cadeia do polissacarídeo e os motivos conservados da cadeia polipeptídica das proteínas envolvidas nesta interação. Os heparam sulfatos possuem papel na sinalização celular como receptores ou coreceptores para diferentes ligantes. Esta ligação dispara vias de sinalização celular levam à fosforilação de diversas proteínas citosólicas ou com ou sem interações diretas com o citoesqueleto, culminando na regulação gênica. O papel dos proteoglicanos de heparam sulfato na sinalização celular e vias de captação endocítica também são discutidas nesta revisão.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo (UNIFESP) Departamento de BioquímicaUniversidade Federal de São Paulo (UNIFESP) Departamento de OftalmologiaUNIFESP, Depto. de BioquímicaUNIFESP, Depto. de OftalmologiaSciEL

Towards the design of 3D multiscale instructive tissue engineering constructs: Current approaches and trends

The design of 3D constructs with adequate properties to instruct and guide cells both in vitro and in vivo is one of the major focuses of tissue engineering. Successful tissue regeneration depends on the favorable crosstalk between the supporting structure, the cells and the host tissue so that a balanced matrix production and degradation is achieved. Herein, the major occurring events and players in normal and regenerative tissue are overviewed. These have been inspiring the selection or synthesis of instructive cues to include into the 3D constructs. We further highlight the importance of a multiscale perception of the range of features that can be included on the biomimetic structures. Lastly, we focus on the current and developing tissue-engineering approaches for the preparation of such 3D constructs: top-down, bottom-up and integrative. Bottom-up and integrative approaches present a higher potential for the design of tissue engineering devices with multiscale features and higher biochemichal control than top-down strategies, and are the main focus of this review.The research leading to these results has received funding from the European Research Council grant agreement ERC-2012-ADG-20120216-321266 for the project ComplexiTE. Portuguese Foundation for Science and Technology is gratefully acknowledged for the fellowship of Sara M. Oliveira (SFRH/BD/70107/2010)