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Sample records for network shows conservation

  1. A human protein interaction network shows conservation of aging processes between human and invertebrate species.

    Directory of Open Access Journals (Sweden)

    Russell Bell

    2009-03-01

    Full Text Available We have mapped a protein interaction network of human homologs of proteins that modify longevity in invertebrate species. This network is derived from a proteome-scale human protein interaction Core Network generated through unbiased high-throughput yeast two-hybrid searches. The longevity network is composed of 175 human homologs of proteins known to confer increased longevity through loss of function in yeast, nematode, or fly, and 2,163 additional human proteins that interact with these homologs. Overall, the network consists of 3,271 binary interactions among 2,338 unique proteins. A comparison of the average node degree of the human longevity homologs with random sets of proteins in the Core Network indicates that human homologs of longevity proteins are highly connected hubs with a mean node degree of 18.8 partners. Shortest path length analysis shows that proteins in this network are significantly more connected than would be expected by chance. To examine the relationship of this network to human aging phenotypes, we compared the genes encoding longevity network proteins to genes known to be changed transcriptionally during aging in human muscle. In the case of both the longevity protein homologs and their interactors, we observed enrichments for differentially expressed genes in the network. To determine whether homologs of human longevity interacting proteins can modulate life span in invertebrates, homologs of 18 human FRAP1 interacting proteins showing significant changes in human aging muscle were tested for effects on nematode life span using RNAi. Of 18 genes tested, 33% extended life span when knocked-down in Caenorhabditis elegans. These observations indicate that a broad class of longevity genes identified in invertebrate models of aging have relevance to human aging. They also indicate that the longevity protein interaction network presented here is enriched for novel conserved longevity proteins.

  2. Identification of Conserved Moieties in Metabolic Networks by Graph Theoretical Analysis of Atom Transition Networks

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    Haraldsdóttir, Hulda S.; Fleming, Ronan M. T.

    2016-01-01

    Conserved moieties are groups of atoms that remain intact in all reactions of a metabolic network. Identification of conserved moieties gives insight into the structure and function of metabolic networks and facilitates metabolic modelling. All moiety conservation relations can be represented as nonnegative integer vectors in the left null space of the stoichiometric matrix corresponding to a biochemical network. Algorithms exist to compute such vectors based only on reaction stoichiometry but their computational complexity has limited their application to relatively small metabolic networks. Moreover, the vectors returned by existing algorithms do not, in general, represent conservation of a specific moiety with a defined atomic structure. Here, we show that identification of conserved moieties requires data on reaction atom mappings in addition to stoichiometry. We present a novel method to identify conserved moieties in metabolic networks by graph theoretical analysis of their underlying atom transition networks. Our method returns the exact group of atoms belonging to each conserved moiety as well as the corresponding vector in the left null space of the stoichiometric matrix. It can be implemented as a pipeline of polynomial time algorithms. Our implementation completes in under five minutes on a metabolic network with more than 4,000 mass balanced reactions. The scalability of the method enables extension of existing applications for moiety conservation relations to genome-scale metabolic networks. We also give examples of new applications made possible by elucidating the atomic structure of conserved moieties. PMID:27870845

  3. Conservation Laws in Biochemical Reaction Networks

    DEFF Research Database (Denmark)

    Mahdi, Adam; Ferragut, Antoni; Valls, Claudia

    2017-01-01

    We study the existence of linear and nonlinear conservation laws in biochemical reaction networks with mass-action kinetics. It is straightforward to compute the linear conservation laws as they are related to the left null-space of the stoichiometry matrix. The nonlinear conservation laws...... are difficult to identify and have rarely been considered in the context of mass-action reaction networks. Here, using the Darboux theory of integrability, we provide necessary structural (i.e., parameterindependent) conditions on a reaction network to guarantee the existence of nonlinear conservation laws...

  4. Network evolution: rewiring and signatures of conservation in signaling.

    Directory of Open Access Journals (Sweden)

    Mark G F Sun

    Full Text Available The analysis of network evolution has been hampered by limited availability of protein interaction data for different organisms. In this study, we investigate evolutionary mechanisms in Src Homology 3 (SH3 domain and kinase interaction networks using high-resolution specificity profiles. We constructed and examined networks for 23 fungal species ranging from Saccharomyces cerevisiae to Schizosaccharomyces pombe. We quantify rates of different rewiring mechanisms and show that interaction change through binding site evolution is faster than through gene gain or loss. We found that SH3 interactions evolve swiftly, at rates similar to those found in phosphoregulation evolution. Importantly, we show that interaction changes are sufficiently rapid to exhibit saturation phenomena at the observed timescales. Finally, focusing on the SH3 interaction network, we observe extensive clustering of binding sites on target proteins by SH3 domains and a strong correlation between the number of domains that bind a target protein (target in-degree and interaction conservation. The relationship between in-degree and interaction conservation is driven by two different effects, namely the number of clusters that correspond to interaction interfaces and the number of domains that bind to each cluster leads to sequence specific conservation, which in turn results in interaction conservation. In summary, we uncover several network evolution mechanisms likely to generalize across peptide recognition modules.

  5. Robust network design for multispecies conservation

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    Ronan Le Bras; Bistra Dilkina; Yexiang Xue; Carla P. Gomes; Kevin S. McKelvey; Michael K. Schwartz; Claire A. Montgomery

    2013-01-01

    Our work is motivated by an important network design application in computational sustainability concerning wildlife conservation. In the face of human development and climate change, it is important that conservation plans for protecting landscape connectivity exhibit certain level of robustness. While previous work has focused on conservation strategies that result...

  6. Collaboration Networks in Applied Conservation Projects across Europe.

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    Nita, Andreea; Rozylowicz, Laurentiu; Manolache, Steluta; Ciocănea, Cristiana Maria; Miu, Iulia Viorica; Popescu, Viorel Dan

    2016-01-01

    The main funding instrument for implementing EU policies on nature conservation and supporting environmental and climate action is the LIFE Nature programme, established by the European Commission in 1992. LIFE Nature projects (>1400 awarded) are applied conservation projects in which partnerships between institutions are critical for successful conservation outcomes, yet little is known about the structure of collaborative networks within and between EU countries. The aim of our study is to understand the nature of collaboration in LIFE Nature projects using a novel application of social network theory at two levels: (1) collaboration between countries, and (2) collaboration within countries using six case studies: Western Europe (United Kingdom and Netherlands), Eastern Europe (Romania and Latvia) and Southern Europe (Greece and Portugal). Using data on 1261 projects financed between 1996 and 2013, we found that Italy was the most successful country not only in terms of awarded number of projects, but also in terms of overall influence being by far the most influent country in the European LIFE Nature network, having the highest eigenvector (0.989) and degree centrality (0.177). Another key player in the network is Netherlands, which ensures a fast communication flow with other network members (closeness-0.318) by staying connected with the most active countries. Although Western European countries have higher centrality scores than most of the Eastern European countries, our results showed that overall there is a lower tendency to create partnerships between different organization categories. Also, the comparisons of the six case studies indicates significant differences in regards to the pattern of creating partnerships, providing valuable information on collaboration on EU nature conservation. This study represents a starting point in predicting the formation of future partnerships within LIFE Nature programme, suggesting ways to improve transnational

  7. The drug target genes show higher evolutionary conservation than non-target genes.

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    Lv, Wenhua; Xu, Yongdeng; Guo, Yiying; Yu, Ziqi; Feng, Guanglong; Liu, Panpan; Luan, Meiwei; Zhu, Hongjie; Liu, Guiyou; Zhang, Mingming; Lv, Hongchao; Duan, Lian; Shang, Zhenwei; Li, Jin; Jiang, Yongshuai; Zhang, Ruijie

    2016-01-26

    Although evidence indicates that drug target genes share some common evolutionary features, there have been few studies analyzing evolutionary features of drug targets from an overall level. Therefore, we conducted an analysis which aimed to investigate the evolutionary characteristics of drug target genes. We compared the evolutionary conservation between human drug target genes and non-target genes by combining both the evolutionary features and network topological properties in human protein-protein interaction network. The evolution rate, conservation score and the percentage of orthologous genes of 21 species were included in our study. Meanwhile, four topological features including the average shortest path length, betweenness centrality, clustering coefficient and degree were considered for comparison analysis. Then we got four results as following: compared with non-drug target genes, 1) drug target genes had lower evolutionary rates; 2) drug target genes had higher conservation scores; 3) drug target genes had higher percentages of orthologous genes and 4) drug target genes had a tighter network structure including higher degrees, betweenness centrality, clustering coefficients and lower average shortest path lengths. These results demonstrate that drug target genes are more evolutionarily conserved than non-drug target genes. We hope that our study will provide valuable information for other researchers who are interested in evolutionary conservation of drug targets.

  8. Gap analysis and conservation network for freshwater wetlands in Central Yangtze Ecoregion.

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    Xiaowen, Li; Haijin, Zhuge; Li, Mengdi

    2013-01-01

    The Central Yangtze Ecoregion contains a large area of internationally important freshwater wetlands and supports a huge number of endangered waterbirds; however, these unique wetlands and the biodiversity they support are under the constant threats of human development pressures, and the prevailing conservation strategies generated based on the local scale cannot adequately be used as guidelines for ecoregion-based conservation initiatives for Central Yangtze at the broad scale. This paper aims at establishing and optimizing an ecological network for freshwater wetland conservation in the Central Yangtze Ecoregion based on large-scale gap analysis. A group of focal species and GIS-based extrapolation technique were employed to identify the potential habitats and conservation gaps, and the optimized conservation network was then established by combining existing protective system and identified conservation gaps. Our results show that only 23.49% of the potential habitats of the focal species have been included in the existing nature reserves in the Central Yangtze Ecoregion. To effectively conserve over 80% of the potential habitats for the focal species by optimizing the existing conservation network for the freshwater wetlands in Central Yangtze Ecoregion, it is necessary to establish new wetland nature reserves in 22 county units across Hubei, Anhui, and Jiangxi provinces.

  9. Dolphin shows and interaction programs: benefits for conservation education?

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    Miller, L J; Zeigler-Hill, V; Mellen, J; Koeppel, J; Greer, T; Kuczaj, S

    2013-01-01

    Dolphin shows and dolphin interaction programs are two types of education programs within zoological institutions used to educate visitors about dolphins and the marine environment. The current study examined the short- and long-term effects of these programs on visitors' conservation-related knowledge, attitude, and behavior. Participants of both dolphin shows and interaction programs demonstrated a significant short-term increase in knowledge, attitudes, and behavioral intentions. Three months following the experience, participants of both dolphin shows and interaction programs retained the knowledge learned during their experience and reported engaging in more conservation-related behaviors. Additionally, the number of dolphin shows attended in the past was a significant predictor of recent conservation-related behavior suggesting that repetition of these types of experiences may be important in inspiring people to conservation action. These results suggest that both dolphin shows and dolphin interaction programs can be an important part of a conservation education program for visitors of zoological facilities. © 2012 Wiley Periodicals, Inc.

  10. Integrating network ecology with applied conservation: a synthesis and guide to implementation.

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    Kaiser-Bunbury, Christopher N; Blüthgen, Nico

    2015-07-10

    Ecological networks are a useful tool to study the complexity of biotic interactions at a community level. Advances in the understanding of network patterns encourage the application of a network approach in other disciplines than theoretical ecology, such as biodiversity conservation. So far, however, practical applications have been meagre. Here we present a framework for network analysis to be harnessed to advance conservation management by using plant-pollinator networks and islands as model systems. Conservation practitioners require indicators to monitor and assess management effectiveness and validate overall conservation goals. By distinguishing between two network attributes, the 'diversity' and 'distribution' of interactions, on three hierarchical levels (species, guild/group and network) we identify seven quantitative metrics to describe changes in network patterns that have implications for conservation. Diversity metrics are partner diversity, vulnerability/generality, interaction diversity and interaction evenness, and distribution metrics are the specialization indices d' and [Formula: see text] and modularity. Distribution metrics account for sampling bias and may therefore be suitable indicators to detect human-induced changes to plant-pollinator communities, thus indirectly assessing the structural and functional robustness and integrity of ecosystems. We propose an implementation pathway that outlines the stages that are required to successfully embed a network approach in biodiversity conservation. Most importantly, only if conservation action and study design are aligned by practitioners and ecologists through joint experiments, are the findings of a conservation network approach equally beneficial for advancing adaptive management and ecological network theory. We list potential obstacles to the framework, highlight the shortfall in empirical, mostly experimental, network data and discuss possible solutions. Published by Oxford University

  11. A conservation planning approach to mitigate the impacts of leakage from protected area networks.

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    Bode, Michael; Tulloch, Ayesha I T; Mills, Morena; Venter, Oscar; Ando, Amy W

    2015-06-01

    Protected area networks are designed to restrict anthropogenic pressures in areas of high biodiversity. Resource users respond by seeking to replace some or all of the lost resources from locations elsewhere in the landscape. Protected area networks thereby perturb the pattern of human pressures by displacing extractive effort from within protected areas into the broader landscape, a process known as leakage. The negative effects of leakage on conservation outcomes have been empirically documented and modeled using homogeneous descriptions of conservation landscapes. Human resource use and biodiversity vary greatly in space, however, and a theory of leakage must describe how this heterogeneity affects the magnitude, pattern, and biodiversity impacts of leakage. We combined models of household utility, adaptive human foraging, and biodiversity conservation to provide a bioeconomic model of leakage that accounts for spatial heterogeneity. Leakage had strong and divergent impacts on the performance of protected area networks, undermining biodiversity benefits but mitigating the negative impacts on local resource users. When leakage was present, our model showed that poorly designed protected area networks resulted in a substantial net loss of biodiversity. However, the effects of leakage can be mitigated if they are incorporated ex-ante into the conservation planning process. If protected areas are coupled with nonreserve policy instruments such as market subsidies, our model shows that the trade-offs between biodiversity and human well-being can be further and more directly reduced. © 2014 Society for Conservation Biology.

  12. Social Network Analysis Identifies Key Participants in Conservation Development.

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    Farr, Cooper M; Reed, Sarah E; Pejchar, Liba

    2018-05-01

    Understanding patterns of participation in private lands conservation, which is often implemented voluntarily by individual citizens and private organizations, could improve its effectiveness at combating biodiversity loss. We used social network analysis (SNA) to examine participation in conservation development (CD), a private land conservation strategy that clusters houses in a small portion of a property while preserving the remaining land as protected open space. Using data from public records for six counties in Colorado, USA, we compared CD participation patterns among counties and identified actors that most often work with others to implement CDs. We found that social network characteristics differed among counties. The network density, or proportion of connections in the network, varied from fewer than 2 to nearly 15%, and was higher in counties with smaller populations and fewer CDs. Centralization, or the degree to which connections are held disproportionately by a few key actors, was not correlated strongly with any county characteristics. Network characteristics were not correlated with the prevalence of wildlife-friendly design features in CDs. The most highly connected actors were biological and geological consultants, surveyors, and engineers. Our work demonstrates a new application of SNA to land-use planning, in which CD network patterns are examined and key actors are identified. For better conservation outcomes of CD, we recommend using network patterns to guide strategies for outreach and information dissemination, and engaging with highly connected actor types to encourage widespread adoption of best practices for CD design and stewardship.

  13. Evolutionary conservation and network structure characterize genes of phenotypic relevance for mitosis in human.

    Directory of Open Access Journals (Sweden)

    Marek Ostaszewski

    Full Text Available The impact of gene silencing on cellular phenotypes is difficult to establish due to the complexity of interactions in the associated biological processes and pathways. A recent genome-wide RNA knock-down study both identified and phenotypically characterized a set of important genes for the cell cycle in HeLa cells. Here, we combine a molecular interaction network analysis, based on physical and functional protein interactions, in conjunction with evolutionary information, to elucidate the common biological and topological properties of these key genes. Our results show that these genes tend to be conserved with their corresponding protein interactions across several species and are key constituents of the evolutionary conserved molecular interaction network. Moreover, a group of bistable network motifs is found to be conserved within this network, which are likely to influence the network stability and therefore the robustness of cellular functioning. They form a cluster, which displays functional homogeneity and is significantly enriched in genes phenotypically relevant for mitosis. Additional results reveal a relationship between specific cellular processes and the phenotypic outcomes induced by gene silencing. This study introduces new ideas regarding the relationship between genotype and phenotype in the context of the cell cycle. We show that the analysis of molecular interaction networks can result in the identification of genes relevant to cellular processes, which is a promising avenue for future research.

  14. Animal Social Network Theory Can Help Wildlife Conservation.

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    Snijders, Lysanne; Blumstein, Daniel T; Stanley, Christina R; Franks, Daniel W

    2017-08-01

    Many animals preferentially associate with certain other individuals. This social structuring can influence how populations respond to changes to their environment, thus making network analysis a promising technique for understanding, predicting, and potentially manipulating population dynamics. Various network statistics can correlate with individual fitness components and key population-level processes, yet the logical role and formal application of animal social network theory for conservation and management have not been well articulated. We outline how understanding of direct and indirect relationships between animals can be profitably applied by wildlife managers and conservationists. By doing so, we aim to stimulate the development and implementation of practical tools for wildlife conservation and management and to inspire novel behavioral research in this field. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effects of budget constraints on conservation network design for biodiversity and ecosystem services

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    Remme, Roy P.; Schröter, Matthias

    2016-01-01

    Limited budgets and budget cuts hamper the development of effective biodiversity conservation networks. Optimizing the spatial configuration of conservation networks given such budget constraints remains challenging. Systematic conservation planning addresses this challenge. Systematic

  16. Self-organized criticality occurs in non-conservative neuronal networks during `up' states

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    Millman, Daniel; Mihalas, Stefan; Kirkwood, Alfredo; Niebur, Ernst

    2010-10-01

    During sleep, under anaesthesia and in vitro, cortical neurons in sensory, motor, association and executive areas fluctuate between so-called up and down states, which are characterized by distinct membrane potentials and spike rates. Another phenomenon observed in preparations similar to those that exhibit up and down states-such as anaesthetized rats, brain slices and cultures devoid of sensory input, as well as awake monkey cortex-is self-organized criticality (SOC). SOC is characterized by activity `avalanches' with a branching parameter near unity and size distribution that obeys a power law with a critical exponent of about -3/2. Recent work has demonstrated SOC in conservative neuronal network models, but critical behaviour breaks down when biologically realistic `leaky' neurons are introduced. Here, we report robust SOC behaviour in networks of non-conservative leaky integrate-and-fire neurons with short-term synaptic depression. We show analytically and numerically that these networks typically have two stable activity levels, corresponding to up and down states, that the networks switch spontaneously between these states and that up states are critical and down states are subcritical.

  17. The Influence of Water Conservancy Projects on River Network Connectivity, A Case of Luanhe River Basin

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    Li, Z.; Li, C.

    2017-12-01

    Connectivity is one of the most important characteristics of a river, which is derived from the natural water cycle and determine the renewability of river water. The water conservancy project can change the connectivity of natural river networks, and directly threaten the health and stability of the river ecosystem. Based on the method of Dendritic Connectivity Index (DCI), the impacts from sluices and dams on the connectivity of river network are deeply discussed herein. DCI quantitatively evaluate the connectivity of river networks based on the number of water conservancy facilities, the connectivity of fish and geographical location. The results show that the number of water conservancy facilities and their location in the river basin have a great influence on the connectivity of the river network. With the increase of the number of sluices and dams, DCI is decreasing gradually, but its decreasing range is becoming smaller and smaller. The dam located in the middle of the river network cuts the upper and lower parts of the whole river network, and destroys the connectivity of the river network more seriously. Therefore, this method can be widely applied to the comparison of different alternatives during planning of river basins and then provide a reference for the site selection and design of the water conservancy project and facility concerned.

  18. Balancing act: Government roles in an energy conservation network

    NARCIS (Netherlands)

    Peterman, A.; Kourula, A.; Levitt, R.

    2014-01-01

    Government-led interorganizational alliance networks present a sensible opportunity to overcome many societal challenges through collaborative governance. In particular, few researchers have studied alliance networks in the field of energy conservation in commercial buildings—a sector with unique

  19. Transcriptional dynamics of a conserved gene expression network associated with craniofacial divergence in Arctic charr.

    Science.gov (United States)

    Ahi, Ehsan Pashay; Kapralova, Kalina Hristova; Pálsson, Arnar; Maier, Valerie Helene; Gudbrandsson, Jóhannes; Snorrason, Sigurdur S; Jónsson, Zophonías O; Franzdóttir, Sigrídur Rut

    2014-01-01

    targets and upstream regulators showed differential expression between the contrasting morphotypes. Interestingly, although selected network genes showed overlapping expression patterns in situ and no morph differences, Timp2 expression patterns differed between morphs. Our comparative study of transcriptional dynamics in divergent craniofacial morphologies of Arctic charr revealed a conserved network of coexpressed genes sharing functional roles in structural morphogenesis. We also implicate transcriptional regulators of the network as targets for future functional studies.

  20. Representation of global and national conservation priorities by Colombia's Protected Area Network.

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    Forero-Medina, German; Joppa, Lucas

    2010-10-12

    How do national-level actions overlap with global priorities for conservation? Answering this question is especially important in countries with high and unique biological diversity like Colombia. Global biodiversity schemes provide conservation guidance at a large scale, while national governments gazette land for protection based on a combination of criteria at regional or local scales. Information on how a protected area network represents global and national conservation priorities is crucial for finding gaps in coverage and for future expansion of the system. We evaluated the agreement of Colombia's protected area network with global conservation priorities, and the extent to which the network reflects the country's biomes, species richness, and common environmental and physical conditions. We used this information to identify priority biomes for conservation. We find the dominant strategy in Colombia has been a proactive one, allocating the highest proportion of protected land on intact, difficult to access and species rich areas like the Amazon. Threatened and unique areas are disproportionately absent from Colombia's protected lands. We highlight six biomes in Colombia as conservation priorities that should be considered in any future expansion of Colombia's protected area network. Two of these biomes have less than 3% of their area protected and more than 70% of their area transformed for human use. One has less than 3% protected and high numbers of threatened vertebrates. Three biomes fall in both categories. Expansion of Colombia's Protected Area Network should consider the current representativeness of the network. We indicate six priority biomes that can contribute to improving the representation of threatened species and biomes in Colombia.

  1. Conservation priorities for mammals in megadiverse Mexico: the efficiency of reserve networks.

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    Ceballos, Gerardo

    2007-03-01

    A major goal of conservation biologists is to identify critical areas for the conservation of biological diversity and then strategically include them in an efficient system of reserves. In general, however, reserve networks have been selected for different objectives, and most countries lack an evaluation of their reserves' ability to represent a percentage of the national diversity. This paper evaluates the effectiveness of a network of reserves to represent the species of mammals in Mexico. The focus of the analyses is on species and site level, evaluating the representation of all terrestrial mammals in the 30 most important reserves. The representation of all species, endemic species, endangered species, and species with restricted distributions in the reserves was assessed and compared. Endemic or endangered species with restricted distributions were expected to be less represented in reserves than were widespread species. The most important reserves for the conservation of mammals were determined with the use of complementarity analyses. Priority sites for the representation of all the species currently absent from the reserve network were then selected. The results have broad applications for conservation. First, 82% of the mammal species from Mexico were represented in the reserve network, which covers a small portion (3.8%) of the country. Second, this percentage is certainly larger as several reserves were not evaluated due to a lack of data. A priority for a national conservation strategy could be to conduct biological surveys in those reserves lacking inventories to evaluate their contribution to conservation. Third, in spite of its demonstrated value, Mexico's reserve network can be improved by designating complementary areas. Additional priority sites, where reserves are required to represent most gap species in the network, were identified. Finally, it is clear that this reserve network has limitations for maintaining biodiversity and ecosystem

  2. Inequity in ecosystem service delivery: Socioeconomic gaps in the public-private conservation network

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    Villamagna, Amy M.; Mogollón, Beatriz; Angermeier, Paul L.

    2017-01-01

    Conservation areas, both public and private, are critical tools to protect biodiversity and deliver important ecosystem services (ES) to society. Although societal benefits from such ES are increasingly used to promote public support of conservation, the number of beneficiaries, their identity, and the magnitude of benefits are largely unknown for the vast majority of conservation areas in the United States public-private conservation network. The location of conservation areas in relation to people strongly influences the direction and magnitude of ES flows as well as the identity of beneficiaries. We analyzed benefit zones, the areas to which selected ES could be conveyed to beneficiaries, to assess who benefits from a typical conservation network. Better knowledge of ES flows and beneficiaries will help land conservationists make a stronger case for the broad collateral benefits of conservation and help to address issues of social-environmental justice. To evaluate who benefits the most from the current public-private conservation network, we delineated the benefit zones for local ES (within 16 km) that are conveyed along hydrological paths from public (federal and state) and private (easements) conservation lands in the states of North Carolina and Virginia, USA. We also discuss the challenges and demonstrate an approach for delineating nonhydrological benefits that are passively conveyed to beneficiaries. We mapped and compared the geographic distribution of benefit zones within and among conservation area types. We further compared beneficiary demographics across benefit zones of the conservation area types and found that hydrological benefit zones of federal protected areas encompass disproportionately fewer minority beneficiaries compared to statewide demographic patterns. In contrast, benefit zones of state protected areas and private easements encompassed a much greater proportion of minority beneficiaries (~22–25%). Benefit zones associated with

  3. Conservation laws for voter-like models on random directed networks

    International Nuclear Information System (INIS)

    Ángeles Serrano, M; Klemm, Konstantin; Vazquez, Federico; Eguíluz, Víctor M; San Miguel, Maxi

    2009-01-01

    We study the voter model, under node and link update, and the related invasion process on a single strongly connected component of a directed network. We implement an analytical treatment in the thermodynamic limit using the heterogeneous mean-field assumption. From the dynamical rules at the microscopic level, we find the equations for the evolution of the relative densities of nodes in a given state on heterogeneous networks with arbitrary degree distribution and degree–degree correlations. We prove that conserved quantities as weighted linear superpositions of spin states exist for all three processes and, for uncorrelated directed networks, we derive their specific expressions. We also discuss the time evolution of the relative densities that decay exponentially to a homogeneous stationary value given by the conserved quantity. The conservation laws obtained in the thermodynamic limit for a system that does not order in that limit determine the probabilities of reaching the absorbing state for a finite system. The contribution of each degree class to the conserved quantity is determined by a local property. Depending on the dynamics, the highest contribution is associated with influential nodes reaching a large number of outgoing neighbors, not too influenceable ones with a low number of incoming connections, or both at the same time

  4. Coexistence and Survival in Conservative Lotka-Volterra Networks

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    Knebel, Johannes; Krüger, Torben; Weber, Markus F.; Frey, Erwin

    2013-04-01

    Analyzing coexistence and survival scenarios of Lotka-Volterra (LV) networks in which the total biomass is conserved is of vital importance for the characterization of long-term dynamics of ecological communities. Here, we introduce a classification scheme for coexistence scenarios in these conservative LV models and quantify the extinction process by employing the Pfaffian of the network’s interaction matrix. We illustrate our findings on global stability properties for general systems of four and five species and find a generalized scaling law for the extinction time.

  5. Identifying all moiety conservation laws in genome-scale metabolic networks.

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    De Martino, Andrea; De Martino, Daniele; Mulet, Roberto; Pagnani, Andrea

    2014-01-01

    The stoichiometry of a metabolic network gives rise to a set of conservation laws for the aggregate level of specific pools of metabolites, which, on one hand, pose dynamical constraints that cross-link the variations of metabolite concentrations and, on the other, provide key insight into a cell's metabolic production capabilities. When the conserved quantity identifies with a chemical moiety, extracting all such conservation laws from the stoichiometry amounts to finding all non-negative integer solutions of a linear system, a programming problem known to be NP-hard. We present an efficient strategy to compute the complete set of integer conservation laws of a genome-scale stoichiometric matrix, also providing a certificate for correctness and maximality of the solution. Our method is deployed for the analysis of moiety conservation relationships in two large-scale reconstructions of the metabolism of the bacterium E. coli, in six tissue-specific human metabolic networks, and, finally, in the human reactome as a whole, revealing that bacterial metabolism could be evolutionarily designed to cover broader production spectra than human metabolism. Convergence to the full set of moiety conservation laws in each case is achieved in extremely reduced computing times. In addition, we uncover a scaling relation that links the size of the independent pool basis to the number of metabolites, for which we present an analytical explanation.

  6. Identifying all moiety conservation laws in genome-scale metabolic networks.

    Directory of Open Access Journals (Sweden)

    Andrea De Martino

    Full Text Available The stoichiometry of a metabolic network gives rise to a set of conservation laws for the aggregate level of specific pools of metabolites, which, on one hand, pose dynamical constraints that cross-link the variations of metabolite concentrations and, on the other, provide key insight into a cell's metabolic production capabilities. When the conserved quantity identifies with a chemical moiety, extracting all such conservation laws from the stoichiometry amounts to finding all non-negative integer solutions of a linear system, a programming problem known to be NP-hard. We present an efficient strategy to compute the complete set of integer conservation laws of a genome-scale stoichiometric matrix, also providing a certificate for correctness and maximality of the solution. Our method is deployed for the analysis of moiety conservation relationships in two large-scale reconstructions of the metabolism of the bacterium E. coli, in six tissue-specific human metabolic networks, and, finally, in the human reactome as a whole, revealing that bacterial metabolism could be evolutionarily designed to cover broader production spectra than human metabolism. Convergence to the full set of moiety conservation laws in each case is achieved in extremely reduced computing times. In addition, we uncover a scaling relation that links the size of the independent pool basis to the number of metabolites, for which we present an analytical explanation.

  7. Diversity and Inclusion in Conservation: A Proposal for a Marine Diversity Network

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    Nicola S. Smith

    2017-08-01

    Full Text Available Low diversity among scientists and practitioners is rampant in conservation. Currently, conservation professionals do not reflect the same diversity of perspectives and experiences of the world as the communities who bear the largest burden for implementing—or adverse consequences for failing to implement—conservation action. Acknowledging and describing the problem is important. But policies and programmes must also be put in place to correct it. Here, we highlight some measurable benefits of workforce diversity, and give an overview of some of the barriers to inclusion in marine conservation that help perpetuate low workforce diversity. Importantly, we underscore actions that both individuals and groups can take to alleviate such barriers. In particular, we describe the establishment of an online Marine Diversity Network, which conference participants proposed during a focus group meeting at the 4th International Marine Conservation Congress. The network will serve to bring together people from across the globe, from a variety of backgrounds, and from all career stages, to share knowledge, experiences and ideas, to provide and receive mentorship in marine conservation, and to forge new collaborations. Removing barriers to diverse participation requires coordinated, mindful actions by individuals and organizations. We hope that the proposed network and other actions presented in this paper find widespread support, and that they might serve both as inspiration and guide to other groups concerned with increasing diversity and inclusivity.

  8. Method and system for conserving power in a telecommunications network during emergency situations

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, Stephen H [Algodones, NM; O' Reilly, Gerard P [Manalapan, NJ

    2011-10-11

    Disclosed is a method and apparatus for conserving power in a telecommunications network during emergency situations. A permissible number list of emergency and/or priority numbers is stored in the telecommunications network. In the event of an emergency or power failure, input digits of a call to the telecommunications network are compared to the permissible number list. The call is processed in the telecommunications network and routed to its destination if the input digits match an entry in the permissible number list. The call is dropped without any further processing if the input digits do not match an entry in the permissible number list. Thus, power can be conserved in emergency situations by only allowing emergency and/or priority calls.

  9. A ChIP-Seq benchmark shows that sequence conservation mainly improves detection of strong transcription factor binding sites.

    Directory of Open Access Journals (Sweden)

    Tony Håndstad

    Full Text Available BACKGROUND: Transcription factors are important controllers of gene expression and mapping transcription factor binding sites (TFBS is key to inferring transcription factor regulatory networks. Several methods for predicting TFBS exist, but there are no standard genome-wide datasets on which to assess the performance of these prediction methods. Also, it is believed that information about sequence conservation across different genomes can generally improve accuracy of motif-based predictors, but it is not clear under what circumstances use of conservation is most beneficial. RESULTS: Here we use published ChIP-seq data and an improved peak detection method to create comprehensive benchmark datasets for prediction methods which use known descriptors or binding motifs to detect TFBS in genomic sequences. We use this benchmark to assess the performance of five different prediction methods and find that the methods that use information about sequence conservation generally perform better than simpler motif-scanning methods. The difference is greater on high-affinity peaks and when using short and information-poor motifs. However, if the motifs are specific and information-rich, we find that simple motif-scanning methods can perform better than conservation-based methods. CONCLUSIONS: Our benchmark provides a comprehensive test that can be used to rank the relative performance of transcription factor binding site prediction methods. Moreover, our results show that, contrary to previous reports, sequence conservation is better suited for predicting strong than weak transcription factor binding sites.

  10. Internet-Based Approaches to Building Stakeholder Networks for Conservation and Natural Resource Management

    Science.gov (United States)

    Kreakie, B. J.; Hychka, K. C.; Belaire, J. A.; Minor, E.; Walker, H. A.

    2016-02-01

    Social network analysis (SNA) is based on a conceptual network representation of social interactions and is an invaluable tool for conservation professionals to increase collaboration, improve information flow, and increase efficiency. We present two approaches to constructing internet-based social networks, and use an existing traditional (survey-based) case study to illustrate in a familiar context the deviations in methods and results. Internet-based approaches to SNA offer a means to overcome institutional hurdles to conducting survey-based SNA, provide unique insight into an institution's web presences, allow for easy snowballing (iterative process that incorporates new nodes in the network), and afford monitoring of social networks through time. The internet-based approaches differ in link definition: hyperlink is based on links on a website that redirect to a different website and relatedness links are based on a Google's "relatedness" operator that identifies pages "similar" to a URL. All networks were initiated with the same start nodes [members of a conservation alliance for the Calumet region around Chicago ( n = 130)], but the resulting networks vary drastically from one another. Interpretation of the resulting networks is highly contingent upon how the links were defined.

  11. Internet-Based Approaches to Building Stakeholder Networks for Conservation and Natural Resource Management.

    Science.gov (United States)

    Social network analysis (SNA) is based on a conceptual network representation of social interactions and is an invaluable tool for conservation professionals to increase collaboration, improve information flow, and increase efficiency. We present two approaches to constructing in...

  12. Business Associations, Conservative Networks, and the Ongoing Republican War over Medicaid Expansion.

    Science.gov (United States)

    Hertel-Fernandez, Alexander; Skocpol, Theda; Lynch, Daniel

    2016-04-01

    A major component of the Affordable Care Act involves the expansion of state Medicaid programs to cover the uninsured poor. In the wake of the 2012 Supreme Court decision upholding and modifying reform legislation, states can decide whether to expand Medicaid-and twenty states are still not proceeding as of August 2015. What explains state choices about participation in expansion, including governors' decisions to endorse expansion or not as well as final state decisions? We tackle this puzzle, focusing closely on outcomes and battles in predominantly Republican-led states. Like earlier scholars, we find that partisan differences between Democrats and Republicans are central, but we go beyond earlier analyses to measure added effects from two dueling factions within the Republican coalition: statewide business associations and cross-state networks of ideologically conservative organizations. Using both statistical modeling and case studies, we show that GOP-leaning or GOP-dominated states have been most likely to embrace the expansion when organized business support outweighs pressures from conservative networks. Our findings help make sense of ongoing state-level debates over a core part of health reform and shed new light on mounting policy tensions within the Republican Party. Copyright © 2016 by Duke University Press.

  13. Can recurrence networks show small-world property?

    International Nuclear Information System (INIS)

    Jacob, Rinku; Harikrishnan, K.P.; Misra, R.; Ambika, G.

    2016-01-01

    Recurrence networks are complex networks, constructed from time series data, having several practical applications. Though their properties when constructed with the threshold value ϵ chosen at or just above the percolation threshold of the network are quite well understood, what happens as the threshold increases beyond the usual operational window is still not clear from a complex network perspective. The present Letter is focused mainly on the network properties at intermediate-to-large values of the recurrence threshold, for which no systematic study has been performed so far. We argue, with numerical support, that recurrence networks constructed from chaotic attractors with ϵ equal to the usual recurrence threshold or slightly above cannot, in general, show small-world property. However, if the threshold is further increased, the recurrence network topology initially changes to a small-world structure and finally to that of a classical random graph as the threshold approaches the size of the strange attractor. - Highlights: • Properties of recurrence networks at intermediate-to-large values of recurrence threshold are analyzed from a complex network perspective. • Using a combined plot of characteristic path length and clustering coefficient, it is shown that the recurrence network constructed with recurrence threshold equal to or just above the percolation threshold cannot, in general, display small-world property. • As the recurrence threshold is increased from its usual operational window, the resulting network makes a smooth transition initially to a small-world network for an intermediate range of thresholds and finally to the classical random graph as the threshold becomes comparable to the size of the attractor.

  14. Can recurrence networks show small-world property?

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Rinku, E-mail: rinku.jacob.vallanat@gmail.com [Department of Physics, The Cochin College, Cochin, 682002 (India); Harikrishnan, K.P., E-mail: kp_hk2002@yahoo.co.in [Department of Physics, The Cochin College, Cochin, 682002 (India); Misra, R., E-mail: rmisra@iucaa.in [Inter University Centre for Astronomy and Astrophysics, Pune, 411007 (India); Ambika, G., E-mail: g.ambika@iiserpune.ac.in [Indian Institute of Science Education and Research, Pune, 411008 (India)

    2016-08-12

    Recurrence networks are complex networks, constructed from time series data, having several practical applications. Though their properties when constructed with the threshold value ϵ chosen at or just above the percolation threshold of the network are quite well understood, what happens as the threshold increases beyond the usual operational window is still not clear from a complex network perspective. The present Letter is focused mainly on the network properties at intermediate-to-large values of the recurrence threshold, for which no systematic study has been performed so far. We argue, with numerical support, that recurrence networks constructed from chaotic attractors with ϵ equal to the usual recurrence threshold or slightly above cannot, in general, show small-world property. However, if the threshold is further increased, the recurrence network topology initially changes to a small-world structure and finally to that of a classical random graph as the threshold approaches the size of the strange attractor. - Highlights: • Properties of recurrence networks at intermediate-to-large values of recurrence threshold are analyzed from a complex network perspective. • Using a combined plot of characteristic path length and clustering coefficient, it is shown that the recurrence network constructed with recurrence threshold equal to or just above the percolation threshold cannot, in general, display small-world property. • As the recurrence threshold is increased from its usual operational window, the resulting network makes a smooth transition initially to a small-world network for an intermediate range of thresholds and finally to the classical random graph as the threshold becomes comparable to the size of the attractor.

  15. Optimal Control of Scalar Conservation Laws Using Linear/Quadratic Programming: Application to Transportation Networks

    KAUST Repository

    Li, Yanning

    2014-03-01

    This article presents a new optimal control framework for transportation networks in which the state is modeled by a first order scalar conservation law. Using an equivalent formulation based on a Hamilton-Jacobi (H-J) equation and the commonly used triangular fundamental diagram, we pose the problem of controlling the state of the system on a network link, in a finite horizon, as a Linear Program (LP). We then show that this framework can be extended to an arbitrary transportation network, resulting in an LP or a Quadratic Program. Unlike many previously investigated transportation network control schemes, this method yields a globally optimal solution and is capable of handling shocks (i.e., discontinuities in the state of the system). As it leverages the intrinsic properties of the H-J equation used to model the state of the system, it does not require any approximation, unlike classical methods that are based on discretizations of the model. The computational efficiency of the method is illustrated on a transportation network. © 2014 IEEE.

  16. Optimal Control of Scalar Conservation Laws Using Linear/Quadratic Programming: Application to Transportation Networks

    KAUST Repository

    Li, Yanning; Canepa, Edward S.; Claudel, Christian

    2014-01-01

    This article presents a new optimal control framework for transportation networks in which the state is modeled by a first order scalar conservation law. Using an equivalent formulation based on a Hamilton-Jacobi (H-J) equation and the commonly used triangular fundamental diagram, we pose the problem of controlling the state of the system on a network link, in a finite horizon, as a Linear Program (LP). We then show that this framework can be extended to an arbitrary transportation network, resulting in an LP or a Quadratic Program. Unlike many previously investigated transportation network control schemes, this method yields a globally optimal solution and is capable of handling shocks (i.e., discontinuities in the state of the system). As it leverages the intrinsic properties of the H-J equation used to model the state of the system, it does not require any approximation, unlike classical methods that are based on discretizations of the model. The computational efficiency of the method is illustrated on a transportation network. © 2014 IEEE.

  17. Spatiotemporal dynamics of surface water networks across a global biodiversity hotspot—implications for conservation

    Science.gov (United States)

    Tulbure, Mirela G.; Kininmonth, Stuart; Broich, Mark

    2014-11-01

    The concept of habitat networks represents an important tool for landscape conservation and management at regional scales. Previous studies simulated degradation of temporally fixed networks but few quantified the change in network connectivity from disintegration of key features that undergo naturally occurring spatiotemporal dynamics. This is particularly of concern for aquatic systems, which typically show high natural spatiotemporal variability. Here we focused on the Swan Coastal Plain, a bioregion that encompasses a global biodiversity hotspot in Australia with over 1500 water bodies of high biodiversity. Using graph theory, we conducted a temporal analysis of water body connectivity over 13 years of variable climate. We derived large networks of surface water bodies using Landsat data (1999-2011). We generated an ensemble of 278 potential networks at three dispersal distances approximating the maximum dispersal distance of different water dependent organisms. We assessed network connectivity through several network topology metrics and quantified the resilience of the network topology during wet and dry phases. We identified ‘stepping stone’ water bodies across time and compared our networks with theoretical network models with known properties. Results showed a highly dynamic seasonal pattern of variability in network topology metrics. A decline in connectivity over the 13 years was noted with potential negative consequences for species with limited dispersal capacity. The networks described here resemble theoretical scale-free models, also known as ‘rich get richer’ algorithm. The ‘stepping stone’ water bodies are located in the area around the Peel-Harvey Estuary, a Ramsar listed site, and some are located in a national park. Our results describe a powerful approach that can be implemented when assessing the connectivity for a particular organism with known dispersal distance. The approach of identifying the surface water bodies that act as

  18. Filling gaps in a large reserve network to address freshwater conservation needs.

    Science.gov (United States)

    Hermoso, Virgilio; Filipe, Ana Filipa; Segurado, Pedro; Beja, Pedro

    2015-09-15

    Freshwater ecosystems and biodiversity are among the most threatened at global scale, but efforts for their conservation have been mostly peripheral to terrestrial conservation. For example, Natura 2000, the world's largest network of protected areas, fails to cover adequately the distribution of rare and endangered aquatic species, and lacks of appropriate spatial design to make conservation for freshwater biodiversity effective. Here, we develop a framework to identify a complementary set of priority areas and enhance the conservation opportunities of Natura 2000 for freshwater biodiversity, using the Iberian Peninsula as a case study. We use a systematic planning approach to identify a minimum set of additional areas that would help i) adequately represent all freshwater fish, amphibians and aquatic reptiles at three different target levels, ii) account for key ecological processes derived from riverscape connectivity, and iii) minimize the impact of threats, both within protected areas and propagated from upstream unprotected areas. Addressing all these goals would need an increase in area between 7 and 46%, depending on the conservation target used and strength of connectivity required. These new priority areas correspond to subcatchments inhabited by endangered and range restricted species, as well as additional subcatchments required to improve connectivity among existing protected areas and to increase protection against upstream threats. Our study should help guide future revisions of the design of Natura 2000, while providing a framework to address deficiencies in reserve networks for adequately protecting freshwater biodiversity elsewhere. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Internet-Based Approaches to Building Stakeholder Networks for Conservation and Natural Resource Management

    OpenAIRE

    Kreakie, B. J.; Hychka, K. C.; Belaire, J. A.; Minor, E.; Walker, H. A.

    2015-01-01

    Social network analysis (SNA) is based on a conceptual network representation of social interactions and is an invaluable tool for conservation professionals to increase collaboration, improve information flow, and increase efficiency. We present two approaches to constructing internet-based social networks, and use an existing traditional (survey-based) case study to illustrate in a familiar context the deviations in methods and results. Internet-based approaches to SNA offer a means to over...

  20. Dynamics of Symmetric Conserved Mass Aggregation Model on Complex Networks

    Institute of Scientific and Technical Information of China (English)

    HUA Da-Yin

    2009-01-01

    We investigate the dynamical behaviour of the aggregation process in the symmetric conserved mass aggregation model under three different topological structures. The dispersion σ(t, L) = (∑i(mi - ρ0)2/L)1/2 is defined to describe the dynamical behaviour where ρ0 is the density of particle and mi is the particle number on a site. It is found numerically that for a regular lattice and a scale-free network, σ(t, L) follows a power-law scaling σ(t, L) ~ tδ1 and σ(t, L) ~ tδ4 from a random initial condition to the stationary states, respectively. However, for a small-world network, there are two power-law scaling regimes, σ(t, L) ~ tδ2 when t<T and a(t, L) ~ tδ3 when tT. Moreover, it is found numerically that δ2 is near to δ1 for small rewiring probability q, and δ3 hardly changes with varying q and it is almost the same as δ4. We speculate that the aggregation of the connection degree accelerates the mass aggregation in the initial relaxation stage and the existence of the long-distance interactions in the complex networks results in the acceleration of the mass aggregation when tT for the small-world networks. We also show that the relaxation time T follows a power-law scaling τ Lz and σ(t, L) in the stationary state follows a power-law σs(L) ~ Lσ for three different structures.

  1. Joint optimization scheduling for water conservancy projects in complex river networks

    Directory of Open Access Journals (Sweden)

    Qin Liu

    2017-01-01

    Full Text Available In this study, we simulated water flow in a water conservancy project consisting of various hydraulic structures, such as sluices, pumping stations, hydropower stations, ship locks, and culverts, and developed a multi-period and multi-variable joint optimization scheduling model for flood control, drainage, and irrigation. In this model, the number of sluice holes, pump units, and hydropower station units to be opened were used as decision variables, and different optimization objectives and constraints were considered. This model was solved with improved genetic algorithms and verified using the Huaian Water Conservancy Project as an example. The results show that the use of the joint optimization scheduling led to a 10% increase in the power generation capacity and a 15% reduction in the total energy consumption. The change in the water level was reduced by 0.25 m upstream of the Yundong Sluice, and by 50% downstream of pumping stations No. 1, No. 2, and No. 4. It is clear that the joint optimization scheduling proposed in this study can effectively improve power generation capacity of the project, minimize operating costs and energy consumption, and enable more stable operation of various hydraulic structures. The results may provide references for the management of water conservancy projects in complex river networks.

  2. Irreversible thermodynamics of open chemical networks. I. Emergent cycles and broken conservation laws

    International Nuclear Information System (INIS)

    Polettini, Matteo; Esposito, Massimiliano

    2014-01-01

    In this paper and Paper II, we outline a general framework for the thermodynamic description of open chemical reaction networks, with special regard to metabolic networks regulating cellular physiology and biochemical functions. We first introduce closed networks “in a box”, whose thermodynamics is subjected to strict physical constraints: the mass-action law, elementarity of processes, and detailed balance. We further digress on the role of solvents and on the seemingly unacknowledged property of network independence of free energy landscapes. We then open the system by assuming that the concentrations of certain substrate species (the chemostats) are fixed, whether because promptly regulated by the environment via contact with reservoirs, or because nearly constant in a time window. As a result, the system is driven out of equilibrium. A rich algebraic and topological structure ensues in the network of internal species: Emergent irreversible cycles are associated with nonvanishing affinities, whose symmetries are dictated by the breakage of conservation laws. These central results are resumed in the relation a + b = s Y between the number of fundamental affinities a, that of broken conservation laws b and the number of chemostats s Y . We decompose the steady state entropy production rate in terms of fundamental fluxes and affinities in the spirit of Schnakenberg's theory of network thermodynamics, paving the way for the forthcoming treatment of the linear regime, of efficiency and tight coupling, of free energy transduction, and of thermodynamic constraints for network reconstruction

  3. Irreversible thermodynamics of open chemical networks. I. Emergent cycles and broken conservation laws.

    Science.gov (United States)

    Polettini, Matteo; Esposito, Massimiliano

    2014-07-14

    In this paper and Paper II, we outline a general framework for the thermodynamic description of open chemical reaction networks, with special regard to metabolic networks regulating cellular physiology and biochemical functions. We first introduce closed networks "in a box", whose thermodynamics is subjected to strict physical constraints: the mass-action law, elementarity of processes, and detailed balance. We further digress on the role of solvents and on the seemingly unacknowledged property of network independence of free energy landscapes. We then open the system by assuming that the concentrations of certain substrate species (the chemostats) are fixed, whether because promptly regulated by the environment via contact with reservoirs, or because nearly constant in a time window. As a result, the system is driven out of equilibrium. A rich algebraic and topological structure ensues in the network of internal species: Emergent irreversible cycles are associated with nonvanishing affinities, whose symmetries are dictated by the breakage of conservation laws. These central results are resumed in the relation a + b = s(Y) between the number of fundamental affinities a, that of broken conservation laws b and the number of chemostats s(Y). We decompose the steady state entropy production rate in terms of fundamental fluxes and affinities in the spirit of Schnakenberg's theory of network thermodynamics, paving the way for the forthcoming treatment of the linear regime, of efficiency and tight coupling, of free energy transduction, and of thermodynamic constraints for network reconstruction.

  4. Climate Change, Northern Birds of Conservation Concern and Matching the Hotspots of Habitat Suitability with the Reserve Network

    Science.gov (United States)

    Virkkala, Raimo; Heikkinen, Risto K.; Fronzek, Stefan; Leikola, Niko

    2013-01-01

    National reserve networks are one of the most important means of species conservation, but their efficiency may be diminished due to the projected climatic changes. Using bioclimatic envelope models and spatial data on habitats and conservation areas, we studied how efficient the reserve network will be in preserving 100 forest, mire, marshland, and alpine bird species of conservation concern in Finland in 2051–2080 under three different climate scenarios. The occurrences of the studied bird species were related to the amount of habitat preferred by each species in the different boreal zones. We employed a novel integrated habitat suitability index that takes into account both the species’ probability of occurrence from the bioclimatic models and the availability of suitable habitat. Using this suitability index, the distribution of the topmost 5% suitability squares (“hotspots”) in the four bird species groups in the period 1971–2000 and under the three scenarios were compared with the location of reserves with the highest amounts of the four habitats to study the efficiency of the network. In species of mires, marshlands, and Arctic mountains, a high proportion of protected habitat was included in the 5% hotspots in the scenarios in 2051–2080, showing that protected areas cover a high proportion of occurrences of bird species. In contrast, in forests in the southern and middle boreal zones, only a small proportion of the protected habitat was included in the 5% hotspots, indicating that the efficiency of the protected area network will be insufficient for forest birds in the future. In the northern boreal zone, the efficiency of the reserve network in forests was highly dependent on the strength of climate change varying between the scenarios. Overall, there is no single solution to preserving biodiversity in a changing climate, but several future pathways should be considered. PMID:23700420

  5. Spatiotemporal dynamics of surface water networks across a global biodiversity hotspot—implications for conservation

    International Nuclear Information System (INIS)

    Tulbure, Mirela G; Broich, Mark; Kininmonth, Stuart

    2014-01-01

    The concept of habitat networks represents an important tool for landscape conservation and management at regional scales. Previous studies simulated degradation of temporally fixed networks but few quantified the change in network connectivity from disintegration of key features that undergo naturally occurring spatiotemporal dynamics. This is particularly of concern for aquatic systems, which typically show high natural spatiotemporal variability. Here we focused on the Swan Coastal Plain, a bioregion that encompasses a global biodiversity hotspot in Australia with over 1500 water bodies of high biodiversity. Using graph theory, we conducted a temporal analysis of water body connectivity over 13 years of variable climate. We derived large networks of surface water bodies using Landsat data (1999–2011). We generated an ensemble of 278 potential networks at three dispersal distances approximating the maximum dispersal distance of different water dependent organisms. We assessed network connectivity through several network topology metrics and quantified the resilience of the network topology during wet and dry phases. We identified ‘stepping stone’ water bodies across time and compared our networks with theoretical network models with known properties. Results showed a highly dynamic seasonal pattern of variability in network topology metrics. A decline in connectivity over the 13 years was noted with potential negative consequences for species with limited dispersal capacity. The networks described here resemble theoretical scale-free models, also known as ‘rich get richer’ algorithm. The ‘stepping stone’ water bodies are located in the area around the Peel-Harvey Estuary, a Ramsar listed site, and some are located in a national park. Our results describe a powerful approach that can be implemented when assessing the connectivity for a particular organism with known dispersal distance. The approach of identifying the surface water bodies that act as

  6. Models of Coupled Settlement and Habitat Networks for Biodiversity Conservation: Conceptual Framework, Implementation and Potential Applications

    Directory of Open Access Journals (Sweden)

    Maarten J. van Strien

    2018-04-01

    Full Text Available Worldwide, the expansion of settlement and transport infrastructure is one of the most important proximate as well as ultimate causes of biodiversity loss. As much as every modern human society depends on a network of settlements that is well-connected by transport infrastructure (i.e., settlement network, animal and plant species depend on networks of habitats between which they can move (i.e., habitat networks. However, changes to a settlement network in a region often threaten the integrity of the region's habitat networks. Determining plans and policy to prevent these threats is made difficult by the numerous interactions and feedbacks that exist between and within the settlement and habitat networks. Mathematical models of coupled settlement and habitat networks can help us understand the dynamics of this social-ecological system. Yet, few attempts have been made to develop such mathematical models. In this paper, we promote the development of models of coupled settlement and habitat networks for biodiversity conservation. First, we present a conceptual framework of key variables that are ideally considered when operationalizing the coupling of settlement and habitat networks. In this framework, we first describe important network-internal interactions by differentiating between the structural (i.e., relating to purely physical conditions determining the suitability of a location for living or movement and functional (i.e., relating to the actual presence, abundance or movement of people or other organisms properties of either network. We then describe the main one-way influences that a settlement network can exert on the habitat networks and vice versa. Second, we give several recommendations for the mathematical modeling of coupled settlement and habitat networks and present several existing modeling approaches (e.g., habitat network models and land-use transport interaction models that could be used for this purpose. Lastly, we elaborate

  7. Study of Multi-Armed Bandits for Energy Conservation in Cognitive Radio Sensor Networks

    Directory of Open Access Journals (Sweden)

    Juan Zhang

    2015-04-01

    Full Text Available Technological advances have led to the emergence of wireless sensor nodes in wireless networks. Sensor nodes are usually battery powered and hence have strict energy constraints. As a result, energy conservation is very important in the wireless sensor network protocol design and the limited power resources are the biggest challenge in wireless network channels. Link adaptation techniques improve the link quality by adjusting medium access control (MAC parameters such as frame size, data rate, and sleep time, thereby improving energy efficiency. In this paper we present an adaptive packet size strategy for energy efficient wireless sensor networks. The main goal is to reduce power consumption and extend the whole network life. In order to achieve this goal, the paper introduces the concept of a bounded MAB to find the optimal packet size to transfer by formulating different packet sizes for different arms under the channel condition. At the same time, in achieve fast convergence, we consider the bandwidth evaluation according to ACK. The experiment shows that the packet size is adaptive when the channel quality changes and our algorithm can obtain the optimal packet size. We observe that the MAB packet size adaptation scheme achieves the best energy efficiency across the whole simulation duration in comparison with the fixed frame size scheme, the random packet size and the extended Kalman filter (EKF.

  8. Topology-function conservation in protein-protein interaction networks.

    Science.gov (United States)

    Davis, Darren; Yaveroğlu, Ömer Nebil; Malod-Dognin, Noël; Stojmirovic, Aleksandar; Pržulj, Nataša

    2015-05-15

    Proteins underlay the functioning of a cell and the wiring of proteins in protein-protein interaction network (PIN) relates to their biological functions. Proteins with similar wiring in the PIN (topology around them) have been shown to have similar functions. This property has been successfully exploited for predicting protein functions. Topological similarity is also used to guide network alignment algorithms that find similarly wired proteins between PINs of different species; these similarities are used to transfer annotation across PINs, e.g. from model organisms to human. To refine these functional predictions and annotation transfers, we need to gain insight into the variability of the topology-function relationships. For example, a function may be significantly associated with specific topologies, while another function may be weakly associated with several different topologies. Also, the topology-function relationships may differ between different species. To improve our understanding of topology-function relationships and of their conservation among species, we develop a statistical framework that is built upon canonical correlation analysis. Using the graphlet degrees to represent the wiring around proteins in PINs and gene ontology (GO) annotations to describe their functions, our framework: (i) characterizes statistically significant topology-function relationships in a given species, and (ii) uncovers the functions that have conserved topology in PINs of different species, which we term topologically orthologous functions. We apply our framework to PINs of yeast and human, identifying seven biological process and two cellular component GO terms to be topologically orthologous for the two organisms. © The Author 2015. Published by Oxford University Press.

  9. Conserved water-mediated hydrogen bond network between TM-I, -II, -VI, and -VII in 7TM receptor activation

    DEFF Research Database (Denmark)

    Nygaard, Rie; Hansen, Louise Valentin; Mokrosinski, Jacek

    2010-01-01

    Five highly conserved polar residues connected by a number of structural water molecules together with two rotamer micro-switches, TrpVI:13 and TyrVII:20, constitute an extended hydrogen bond network between the intracellular segments of TM-I, -II, -VI, and -VII of 7TM receptors. Molecular dynamics...... to apparently function as a catching trap for water molecules. Mutational analysis of the beta2-adrenergic receptor demonstrated that the highly conserved polar residues of the hydrogen bond network were all important for receptor signaling but served different functions, some dampening constitutive activity...... (AsnI:18, AspII:10, and AsnVII:13), whereas others (AsnVII:12 and AsnVII:16) located one helical turn apart and sharing a water molecule were shown to be essential for agonist-induced signaling. It is concluded that the conserved water hydrogen bond network of 7TM receptors constitutes an extended...

  10. Systems level analysis of systemic sclerosis shows a network of immune and profibrotic pathways connected with genetic polymorphisms.

    Directory of Open Access Journals (Sweden)

    J Matthew Mahoney

    2015-01-01

    Full Text Available Systemic sclerosis (SSc is a rare systemic autoimmune disease characterized by skin and organ fibrosis. The pathogenesis of SSc and its progression are poorly understood. The SSc intrinsic gene expression subsets (inflammatory, fibroproliferative, normal-like, and limited are observed in multiple clinical cohorts of patients with SSc. Analysis of longitudinal skin biopsies suggests that a patient's subset assignment is stable over 6-12 months. Genetically, SSc is multi-factorial with many genetic risk loci for SSc generally and for specific clinical manifestations. Here we identify the genes consistently associated with the intrinsic subsets across three independent cohorts, show the relationship between these genes using a gene-gene interaction network, and place the genetic risk loci in the context of the intrinsic subsets. To identify gene expression modules common to three independent datasets from three different clinical centers, we developed a consensus clustering procedure based on mutual information of partitions, an information theory concept, and performed a meta-analysis of these genome-wide gene expression datasets. We created a gene-gene interaction network of the conserved molecular features across the intrinsic subsets and analyzed their connections with SSc-associated genetic polymorphisms. The network is composed of distinct, but interconnected, components related to interferon activation, M2 macrophages, adaptive immunity, extracellular matrix remodeling, and cell proliferation. The network shows extensive connections between the inflammatory- and fibroproliferative-specific genes. The network also shows connections between these subset-specific genes and 30 SSc-associated polymorphic genes including STAT4, BLK, IRF7, NOTCH4, PLAUR, CSK, IRAK1, and several human leukocyte antigen (HLA genes. Our analyses suggest that the gene expression changes underlying the SSc subsets may be long-lived, but mechanistically interconnected

  11. Construction and comparison of gene co-expression networks shows complex plant immune responses

    Directory of Open Access Journals (Sweden)

    Luis Guillermo Leal

    2014-10-01

    Full Text Available Gene co-expression networks (GCNs are graphic representations that depict the coordinated transcription of genes in response to certain stimuli. GCNs provide functional annotations of genes whose function is unknown and are further used in studies of translational functional genomics among species. In this work, a methodology for the reconstruction and comparison of GCNs is presented. This approach was applied using gene expression data that were obtained from immunity experiments in Arabidopsis thaliana, rice, soybean, tomato and cassava. After the evaluation of diverse similarity metrics for the GCN reconstruction, we recommended the mutual information coefficient measurement and a clustering coefficient-based method for similarity threshold selection. To compare GCNs, we proposed a multivariate approach based on the Principal Component Analysis (PCA. Branches of plant immunity that were exemplified by each experiment were analyzed in conjunction with the PCA results, suggesting both the robustness and the dynamic nature of the cellular responses. The dynamic of molecular plant responses produced networks with different characteristics that are differentiable using our methodology. The comparison of GCNs from plant pathosystems, showed that in response to similar pathogens plants could activate conserved signaling pathways. The results confirmed that the closeness of GCNs projected on the principal component space is an indicative of similarity among GCNs. This also can be used to understand global patterns of events triggered during plant immune responses.

  12. Landscape Conservation Cooperatives: Creating a Collaborative Conservation Vision in the Face of Climate Change Uncertainty

    Science.gov (United States)

    Athearn, N.; Schlafmann, D.

    2015-12-01

    The 22 Landscape Conservation Cooperatives (LCCs) form a "network of networks," each defined by the characteristics of its ecoregion and its unique community of conservation managers, practitioners, and scientists. As self-directed partnerships, LCCs are strongly influenced not only by the landscape but by the evolving cultures and values that define the multi-faceted relationships between people and place. LCCs maintain an ecologically connected network across these diverse landscapes by transcending borders and leveraging resources. Natural resource managers are challenged to make decisions in the face of multiple uncertainties, and several partners across the network have recognized that climate change is one important uncertainty that spans boundaries - both across the conservation community and beyond. The impacts of climate change across the LCC Network are likely to be as diverse as the network itself - manifesting as, for example, sea level rise, ocean acidification, loss of sea ice, and shifts in climate patterns and timing - but synergies are being leveraged within and between LCCs and national climate-focused programs to systematically address the needs of the network to support a collaborative conservation vision that addresses multiple landscape-scale stressors in the face of climate uncertainties. This vision is being achieved by leveraging the convening power of the LCCs and collaborating with DOI Climate Science Centers and others. Selected case studies will demonstrate how the network finds strength in its differences, but also reveals powerful collaborative opportunities through integrated science, shared conservation strategies, and strategic approaches for translating targeted science to conservation action. These examples exemplify past successes as well as ongoing efforts as the network continues to bring about effective application of climate science to achieve conservation outcomes across the LCC Network in an uncertain future climate.

  13. Modeling and Analysis of Energy Conservation Scheme Based on Duty Cycling in Wireless Ad Hoc Sensor Network

    Science.gov (United States)

    Chung, Yun Won; Hwang, Ho Young

    2010-01-01

    In sensor network, energy conservation is one of the most critical issues since sensor nodes should perform a sensing task for a long time (e.g., lasting a few years) but the battery of them cannot be replaced in most practical situations. For this purpose, numerous energy conservation schemes have been proposed and duty cycling scheme is considered the most suitable power conservation technique, where sensor nodes alternate between states having different levels of power consumption. In order to analyze the energy consumption of energy conservation scheme based on duty cycling, it is essential to obtain the probability of each state. In this paper, we analytically derive steady state probability of sensor node states, i.e., sleep, listen, and active states, based on traffic characteristics and timer values, i.e., sleep timer, listen timer, and active timer. The effect of traffic characteristics and timer values on the steady state probability and energy consumption is analyzed in detail. Our work can provide sensor network operators guideline for selecting appropriate timer values for efficient energy conservation. The analytical methodology developed in this paper can be extended to other energy conservation schemes based on duty cycling with different sensor node states, without much difficulty. PMID:22219676

  14. Modeling and Analysis of Energy Conservation Scheme Based on Duty Cycling in Wireless Ad Hoc Sensor Network

    Directory of Open Access Journals (Sweden)

    Yun Won Chung

    2010-06-01

    Full Text Available In sensor network, energy conservation is one of the most critical issues since sensor nodes should perform a sensing task for a long time (e.g., lasting a few years but the battery of them cannot be replaced in most practical situations. For this purpose, numerous energy conservation schemes have been proposed and duty cycling scheme is considered the most suitable power conservation technique, where sensor nodes alternate between states having different levels of power consumption. In order to analyze the energy consumption of energy conservation scheme based on duty cycling, it is essential to obtain the probability of each state. In this paper, we analytically derive steady state probability of sensor node states, i.e., sleep, listen, and active states, based on traffic characteristics and timer values, i.e., sleep timer, listen timer, and active timer. The effect of traffic characteristics and timer values on the steady state probability and energy consumption is analyzed in detail. Our work can provide sensor network operators guideline for selecting appropriate timer values for efficient energy conservation. The analytical methodology developed in this paper can be extended to other energy conservation schemes based on duty cycling with different sensor node states, without much difficulty.

  15. Relative Stabilities of Conserved and Non-Conserved Structures in the OB-Fold Superfamily

    Directory of Open Access Journals (Sweden)

    Andrei T. Alexandrescu

    2009-05-01

    Full Text Available The OB-fold is a diverse structure superfamily based on a β-barrel motif that is often supplemented with additional non-conserved secondary structures. Previous deletion mutagenesis and NMR hydrogen exchange studies of three OB-fold proteins showed that the structural stabilities of sites within the conserved β-barrels were larger than sites in non-conserved segments. In this work we examined a database of 80 representative domain structures currently classified as OB-folds, to establish the basis of this effect. Residue-specific values were obtained for the number of Cα-Cα distance contacts, sequence hydrophobicities, crystallographic B-factors, and theoretical B-factors calculated from a Gaussian Network Model. All four parameters point to a larger average flexibility for the non-conserved structures compared to the conserved β-barrels. The theoretical B-factors and contact densities show the highest sensitivity.Our results suggest a model of protein structure evolution in which novel structural features develop at the periphery of conserved motifs. Core residues are more resistant to structural changes during evolution since their substitution would disrupt a larger number of interactions. Similar factors are likely to account for the differences in stability to unfolding between conserved and non-conserved structures.

  16. Targeting climate diversity in conservation planning to build resilience to climate change

    Science.gov (United States)

    Heller, Nicole E.; Kreitler, Jason R.; Ackerly, David; Weiss, Stuart; Recinos, Amanda; Branciforte, Ryan; Flint, Lorraine E.; Flint, Alan L.; Micheli, Elisabeth

    2015-01-01

    Climate change is raising challenging concerns for systematic conservation planning. Are methods based on the current spatial patterns of biodiversity effective given long-term climate change? Some conservation scientists argue that planning should focus on protecting the abiotic diversity in the landscape, which drives patterns of biological diversity, rather than focusing on the distribution of focal species, which shift in response to climate change. Climate is one important abiotic driver of biodiversity patterns, as different climates host different biological communities and genetic pools. We propose conservation networks that capture the full range of climatic diversity in a region will improve the resilience of biotic communities to climate change compared to networks that do not. In this study we used historical and future hydro-climate projections from the high resolution Basin Characterization Model to explore the utility of directly targeting climatic diversity in planning. Using the spatial planning tool, Marxan, we designed conservation networks to capture the diversity of climate types, at the regional and sub-regional scale, and compared them to networks we designed to capture the diversity of vegetation types. By focusing on the Conservation Lands Network (CLN) of the San Francisco Bay Area as a real-world case study, we compared the potential resilience of networks by examining two factors: the range of climate space captured, and climatic stability to 18 future climates, reflecting different emission scenarios and global climate models. We found that the climate-based network planned at the sub-regional scale captured a greater range of climate space and showed higher climatic stability than the vegetation and regional based-networks. At the same time, differences among network scenarios are small relative to the variance in climate stability across global climate models. Across different projected futures, topographically heterogeneous areas

  17. A Conserved Circular Network of Coregulated Lipids Modulates Innate Immune Responses.

    Science.gov (United States)

    Köberlin, Marielle S; Snijder, Berend; Heinz, Leonhard X; Baumann, Christoph L; Fauster, Astrid; Vladimer, Gregory I; Gavin, Anne-Claude; Superti-Furga, Giulio

    2015-07-02

    Lipid composition affects the biophysical properties of membranes that provide a platform for receptor-mediated cellular signaling. To study the regulatory role of membrane lipid composition, we combined genetic perturbations of sphingolipid metabolism with the quantification of diverse steps in Toll-like receptor (TLR) signaling and mass spectrometry-based lipidomics. Membrane lipid composition was broadly affected by these perturbations, revealing a circular network of coregulated sphingolipids and glycerophospholipids. This evolutionarily conserved network architecture simultaneously reflected membrane lipid metabolism, subcellular localization, and adaptation mechanisms. Integration of the diverse TLR-induced inflammatory phenotypes with changes in lipid abundance assigned distinct functional roles to individual lipid species organized across the network. This functional annotation accurately predicted the inflammatory response of cells derived from patients suffering from lipid storage disorders, based solely on their altered membrane lipid composition. The analytical strategy described here empowers the understanding of higher-level organization of membrane lipid function in diverse biological systems. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. A Survey on Energy Conserving Mechanisms for the Internet of Things: Wireless Networking Aspects.

    Science.gov (United States)

    Abbas, Zeeshan; Yoon, Wonyong

    2015-09-25

    The Internet of Things (IoT) is an emerging key technology for future industries and everyday lives of people, where a myriad of battery operated sensors, actuators, and smart objects are connected to the Internet to provide services such as mobile healthcare, intelligent transport system, environmental monitoring, etc. Since energy efficiency is of utmost importance to these battery constrained IoT devices, IoT-related standards and research works have focused on the device energy conserving issues. This paper presents a comprehensive survey on energy conserving issues and solutions in using diverse wireless radio access technologies for IoT connectivity, e.g., the 3rd Generation Partnership Project (3GPP) machine type communications, IEEE 802.11ah, Bluetooth Low Energy (BLE), and Z-Wave. We look into the literature in broad areas of standardization, academic research, and industry development, and structurally summarize the energy conserving solutions based on several technical criteria. We also propose future research directions regarding energy conserving issues in wireless networking-based IoT.

  19. The Moves of a Bajau Middlewomen: Understanding the Disparity between Trade Networks and Marine Conservation.

    NARCIS (Netherlands)

    Pauwelussen, A.P.

    2015-01-01

    At the interface of Indonesia and Malaysia, border-crossing maritime trade appears to elude attempts to conserve marine resources. In Berau district (East Kalimantan) attempts to protect coastal waters from illegal fishing and trade fail to correspond with mobile trade networks. In this article, I

  20. Exploring Conservation Options in the Broad-Leaved Korean Pine Mixed Forest of the Changbai Mountain Region

    Directory of Open Access Journals (Sweden)

    Lin Ma

    2015-05-01

    Full Text Available The broad-leaved Korean pine (Pinus koraiensis mixed forest (BKPF is one of the most biodiverse zonal communities in the northern temperate zone. Changbai Mountain in northeastern China contains one of the largest BKPFs in the region. The government of China has established a network of 23 nature reserves to protect the BKPF and the species that depend on it for habitat, including the endangered Siberian tiger (Panthera tigris altaica. This study used the conservation planning software C-Plan to calculate the irreplaceability value of each unit to assess how efficiently and comprehensively the existing conservation network supports biodiversity and to identify gap areas that, if integrated into the network, would expand its protection capability. Results show a number of high-conservation-value planning units concentrated along certain ridges. The existing conservation network is structured such that the habitats of only 24 species (out of a total of 75 achieve established conservation targets. Of the other 51 species, 20 achieve less than 50% of their conservation targets. However, expanding the network to include high-conservation-value gap areas could achieve conservation targets for 64 species and could provide different degrees of protection to the other 11 species. Using C-Plan software can guide decision-making to expand the conservation network in this most precious of mountainous ecological zones.

  1. The Middle Eastern Biodiversity Network: Generating and sharing knowledge for ecosystem management and conservation

    Directory of Open Access Journals (Sweden)

    Friedhelm Krupp

    2009-12-01

    Full Text Available Despite prevailing arid conditions, the diversity of terrestrial and freshwater biota in the Middle East is amazingly high and marine biodiversity is the second highest on Earth. Throughout the region, threats to the environment are moderate to severe. Despite the outstanding economic and ecological importance of biological diversity, the capacity in biodiversity-related research and education is inadequate in most parts of the Middle East. The ";;Middle Eastern Biodiversity Network";; (MEBN, founded in 2006 by six universities and research institutes in Iran, Jordan, Germany, Lebanon and Yemen was designed to fill this gap. An integrated approach is taken to upgrade biodiversity research and education to improve regional ecosystem conservation and management capacities. A wide range of activities are carried out in the framework of the Network, including capacity building in biological collection management and professional natural history curatorship, developing university curricula in biodiversity, conducting scientific research, organising workshops and conferences on Middle Eastern biodiversity, and translating the results of biodiversity research into conservation and sustainable development.

  2. A Survey on Energy Conserving Mechanisms for the Internet of Things: Wireless Networking Aspects

    Directory of Open Access Journals (Sweden)

    Zeeshan Abbas

    2015-09-01

    Full Text Available The Internet of Things (IoT is an emerging key technology for future industries and everyday lives of people, where a myriad of battery operated sensors, actuators, and smart objects are connected to the Internet to provide services such as mobile healthcare, intelligent transport system, environmental monitoring, etc. Since energy efficiency is of utmost importance to these battery constrained IoT devices, IoT-related standards and research works have focused on the device energy conserving issues. This paper presents a comprehensive survey on energy conserving issues and solutions in using diverse wireless radio access technologies for IoT connectivity, e.g., the 3rd Generation Partnership Project (3GPP machine type communications, IEEE 802.11ah, Bluetooth Low Energy (BLE, and Z-Wave. We look into the literature in broad areas of standardization, academic research, and industry development, and structurally summarize the energy conserving solutions based on several technical criteria. We also propose future research directions regarding energy conserving issues in wireless networking-based IoT.

  3. A Survey on Energy Conserving Mechanisms for the Internet of Things: Wireless Networking Aspects

    Science.gov (United States)

    Abbas, Zeeshan; Yoon, Wonyong

    2015-01-01

    The Internet of Things (IoT) is an emerging key technology for future industries and everyday lives of people, where a myriad of battery operated sensors, actuators, and smart objects are connected to the Internet to provide services such as mobile healthcare, intelligent transport system, environmental monitoring, etc. Since energy efficiency is of utmost importance to these battery constrained IoT devices, IoT-related standards and research works have focused on the device energy conserving issues. This paper presents a comprehensive survey on energy conserving issues and solutions in using diverse wireless radio access technologies for IoT connectivity, e.g., the 3rd Generation Partnership Project (3GPP) machine type communications, IEEE 802.11ah, Bluetooth Low Energy (BLE), and Z-Wave. We look into the literature in broad areas of standardization, academic research, and industry development, and structurally summarize the energy conserving solutions based on several technical criteria. We also propose future research directions regarding energy conserving issues in wireless networking-based IoT. PMID:26404275

  4. Development of Non-Conservative Joints in Beam Networks for Vibration Energy Flow Analysis

    Directory of Open Access Journals (Sweden)

    Jee-Hun Song

    2007-01-01

    Full Text Available Our work aims to find a general solution for the vibrational energy flow through a plane network of beams on the basis of an energy flow analysis. A joint between two semi-infinite beams are modeled by three sets of springs and dashpots. Thus, the results can incorporate the case of complaint and non-conservative in all the three degrees of freedom. In the cases of finite coupled structures connected at a certain angle, the derived non-conservative joints and developed wave energy equation were applied. The joint properties, the frequency, the coupling angle, and the internal loss factor were changed to evaluate the proposed methods for predicting medium-to-high frequency vibrational energy and intensity distributions.

  5. Bridging Organizations Drive Effective Governance Outcomes for Conservation of Indonesia's Marine Systems.

    Science.gov (United States)

    Berdej, Samantha M; Armitage, Derek R

    2016-01-01

    This study empirically investigates the influence of bridging organizations on governance outcomes for marine conservation in Indonesia. Conservation challenges require ways of governing that are collaborative and adaptive across boundaries, and where conservation actions are better coordinated, information flows improved, and knowledge better integrated and mobilized. We combine quantitative social network analysis and qualitative data to analyze bridging organizations and their networks, and to understand their contributions and constraints in two case studies in Bali, Indonesia. The analysis shows 1) bridging organizations help to navigate the 'messiness' inherent in conservation settings by compensating for sparse linkages, 2) the particular structure and function of bridging organizations influence governing processes (i.e., collaboration, knowledge sharing) and subsequent conservation outcomes, 3) 'bridging' is accomplished using different strategies and platforms for collaboration and social learning, and 4) bridging organizations enhance flexibility to adjust to changing marine conservation contexts and needs. Understanding the organizations that occupy bridging positions, and how they utilize their positionality in a governance network is emerging as an important determinant of successful conservation outcomes. Our findings contribute to a relatively new body of literature on bridging organizations in marine conservation contexts, and add needed empirical investigation into their value to governance and conservation in Coral Triangle nations and beyond.

  6. Genome-Scale Co-Expression Network Comparison across Escherichia coli and Salmonella enterica Serovar Typhimurium Reveals Significant Conservation at the Regulon Level of Local Regulators Despite Their Dissimilar Lifestyles

    Science.gov (United States)

    Zarrineh, Peyman; Sánchez-Rodríguez, Aminael; Hosseinkhan, Nazanin; Narimani, Zahra; Marchal, Kathleen; Masoudi-Nejad, Ali

    2014-01-01

    Availability of genome-wide gene expression datasets provides the opportunity to study gene expression across different organisms under a plethora of experimental conditions. In our previous work, we developed an algorithm called COMODO (COnserved MODules across Organisms) that identifies conserved expression modules between two species. In the present study, we expanded COMODO to detect the co-expression conservation across three organisms by adapting the statistics behind it. We applied COMODO to study expression conservation/divergence between Escherichia coli, Salmonella enterica, and Bacillus subtilis. We observed that some parts of the regulatory interaction networks were conserved between E. coli and S. enterica especially in the regulon of local regulators. However, such conservation was not observed between the regulatory interaction networks of B. subtilis and the two other species. We found co-expression conservation on a number of genes involved in quorum sensing, but almost no conservation for genes involved in pathogenicity across E. coli and S. enterica which could partially explain their different lifestyles. We concluded that despite their different lifestyles, no significant rewiring have occurred at the level of local regulons involved for instance, and notable conservation can be detected in signaling pathways and stress sensing in the phylogenetically close species S. enterica and E. coli. Moreover, conservation of local regulons seems to depend on the evolutionary time of divergence across species disappearing at larger distances as shown by the comparison with B. subtilis. Global regulons follow a different trend and show major rewiring even at the limited evolutionary distance that separates E. coli and S. enterica. PMID:25101984

  7. Evolutionary Conservation and Emerging Functional Diversity of the Cytosolic Hsp70:J Protein Chaperone Network of Arabidopsis thaliana.

    Science.gov (United States)

    Verma, Amit K; Diwan, Danish; Raut, Sandeep; Dobriyal, Neha; Brown, Rebecca E; Gowda, Vinita; Hines, Justin K; Sahi, Chandan

    2017-06-07

    Heat shock proteins of 70 kDa (Hsp70s) partner with structurally diverse Hsp40s (J proteins), generating distinct chaperone networks in various cellular compartments that perform myriad housekeeping and stress-associated functions in all organisms. Plants, being sessile, need to constantly maintain their cellular proteostasis in response to external environmental cues. In these situations, the Hsp70:J protein machines may play an important role in fine-tuning cellular protein quality control. Although ubiquitous, the functional specificity and complexity of the plant Hsp70:J protein network has not been studied. Here, we analyzed the J protein network in the cytosol of Arabidopsis thaliana and, using yeast genetics, show that the functional specificities of most plant J proteins in fundamental chaperone functions are conserved across long evolutionary timescales. Detailed phylogenetic and functional analysis revealed that increased number, regulatory differences, and neofunctionalization in J proteins together contribute to the emerging functional diversity and complexity in the Hsp70:J protein network in higher plants. Based on the data presented, we propose that higher plants have orchestrated their "chaperome," especially their J protein complement, according to their specialized cellular and physiological stipulations. Copyright © 2017 Verma et al.

  8. Comprehensive analysis of coding-lncRNA gene co-expression network uncovers conserved functional lncRNAs in zebrafish.

    Science.gov (United States)

    Chen, Wen; Zhang, Xuan; Li, Jing; Huang, Shulan; Xiang, Shuanglin; Hu, Xiang; Liu, Changning

    2018-05-09

    Zebrafish is a full-developed model system for studying development processes and human disease. Recent studies of deep sequencing had discovered a large number of long non-coding RNAs (lncRNAs) in zebrafish. However, only few of them had been functionally characterized. Therefore, how to take advantage of the mature zebrafish system to deeply investigate the lncRNAs' function and conservation is really intriguing. We systematically collected and analyzed a series of zebrafish RNA-seq data, then combined them with resources from known database and literatures. As a result, we obtained by far the most complete dataset of zebrafish lncRNAs, containing 13,604 lncRNA genes (21,128 transcripts) in total. Based on that, a co-expression network upon zebrafish coding and lncRNA genes was constructed and analyzed, and used to predict the Gene Ontology (GO) and the KEGG annotation of lncRNA. Meanwhile, we made a conservation analysis on zebrafish lncRNA, identifying 1828 conserved zebrafish lncRNA genes (1890 transcripts) that have their putative mammalian orthologs. We also found that zebrafish lncRNAs play important roles in regulation of the development and function of nervous system; these conserved lncRNAs present a significant sequential and functional conservation, with their mammalian counterparts. By integrative data analysis and construction of coding-lncRNA gene co-expression network, we gained the most comprehensive dataset of zebrafish lncRNAs up to present, as well as their systematic annotations and comprehensive analyses on function and conservation. Our study provides a reliable zebrafish-based platform to deeply explore lncRNA function and mechanism, as well as the lncRNA commonality between zebrafish and human.

  9. Maximizing species conservation in continental Ecuador: a case of systematic conservation planning for biodiverse regions

    Science.gov (United States)

    Lessmann, Janeth; Muñoz, Jesús; Bonaccorso, Elisa

    2014-01-01

    Ecuador has the largest number of species by area worldwide, but also a low representation of species within its protected areas. Here, we applied systematic conservation planning to identify potential areas for conservation in continental Ecuador, with the aim of increasing the representation of terrestrial species diversity in the protected area network. We selected 809 terrestrial species (amphibians, birds, mammals, and plants), for which distributions were estimated via species distribution models (SDMs), using Maxent. For each species we established conservation goals based on conservation priorities, and estimated new potential protected areas using Marxan conservation planning software. For each selected area, we determined their conservation priority and feasibility of establishment, two important aspects in the decision-making processes. We found that according to our conservation goals, the current protected area network contains large conservation gaps. Potential areas for conservation almost double the surface area of currently protected areas. Most of the newly proposed areas are located in the Coast, a region with large conservation gaps and irreversible changes in land use. The most feasible areas for conservation were found in the Amazon and Andes regions, which encompass more undisturbed habitats, and already harbor most of the current reserves. Our study allows defining a viable strategy for preserving Ecuador's biodiversity, by combining SDMs, GIS-based decision-support software, and priority and feasibility assessments of the selected areas. This approach is useful for complementing protected area networks in countries with great biodiversity, insufficient biological information, and limited resources for conservation. PMID:25360277

  10. Range-wide network of priority areas for greater sage-grouse - a design for conserving connected distributions or isolating individual zoos?

    Science.gov (United States)

    Crist, Michele R.; Knick, Steven T.; Hanser, Steven E.

    2015-09-08

    The network of areas delineated in 11 Western States for prioritizing management of greater sage-grouse (Centrocercus urophasianus) represents a grand experiment in conservation biology and reserve design. We used centrality metrics from social network theory to gain insights into how this priority area network might function. The network was highly centralized. Twenty of 188 priority areas accounted for 80 percent of the total centrality scores. These priority areas, characterized by large size and a central location in the range-wide distribution, are strongholds for greater sage-grouse populations and also might function as sources. Mid-ranking priority areas may serve as stepping stones because of their location between large central and smaller peripheral priority areas. The current network design and conservation strategy has risks. The contribution of almost one-half (n = 93) of the priority areas combined for less than 1 percent of the cumulative centrality scores for the network. These priority areas individually are likely too small to support viable sage-grouse populations within their boundary. Without habitat corridors to connect small priority areas either to larger priority areas or as a clustered group within the network, their isolation could lead to loss of sage-grouse within these regions of the network

  11. Ecological-niche modeling and prioritization of conservation-area networks for Mexican herpetofauna.

    Science.gov (United States)

    Urbina-Cardona, J Nicolás; Flores-Villela, Oscar

    2010-08-01

    One of the most important tools in conservation biology is information on the geographic distribution of species and the variables determining those patterns. We used maximum-entropy niche modeling to run distribution models for 222 amphibian and 371 reptile species (49% endemics and 27% threatened) for which we had 34,619 single geographic records. The planning region is in southeastern Mexico, is 20% of the country's area, includes 80% of the country's herpetofauna, and lacks an adequate protected-area system. We used probabilistic data to build distribution models of herpetofauna for use in prioritizing conservation areas for three target groups (all species and threatened and endemic species). The accuracy of species-distribution models was better for endemic and threatened species than it was for all species. Forty-seven percent of the region has been deforested and additional conservation areas with 13.7% to 88.6% more native vegetation (76% to 96% of the areas are outside the current protected-area system) are needed. There was overlap in 26 of the main selected areas in the conservation-area network prioritized to preserve the target groups, and for all three target groups the proportion of vegetation types needed for their conservation was constant: 30% pine and oak forests, 22% tropical evergreen forest, 17% low deciduous forest, and 8% montane cloud forests. The fact that different groups of species require the same proportion of habitat types suggests that the pine and oak forests support the highest proportion of endemic and threatened species and should therefore be given priority over other types of vegetation for inclusion in the protected areas of southeastern Mexico.

  12. L-GRAAL: Lagrangian graphlet-based network aligner.

    Science.gov (United States)

    Malod-Dognin, Noël; Pržulj, Nataša

    2015-07-01

    Discovering and understanding patterns in networks of protein-protein interactions (PPIs) is a central problem in systems biology. Alignments between these networks aid functional understanding as they uncover important information, such as evolutionary conserved pathways, protein complexes and functional orthologs. A few methods have been proposed for global PPI network alignments, but because of NP-completeness of underlying sub-graph isomorphism problem, producing topologically and biologically accurate alignments remains a challenge. We introduce a novel global network alignment tool, Lagrangian GRAphlet-based ALigner (L-GRAAL), which directly optimizes both the protein and the interaction functional conservations, using a novel alignment search heuristic based on integer programming and Lagrangian relaxation. We compare L-GRAAL with the state-of-the-art network aligners on the largest available PPI networks from BioGRID and observe that L-GRAAL uncovers the largest common sub-graphs between the networks, as measured by edge-correctness and symmetric sub-structures scores, which allow transferring more functional information across networks. We assess the biological quality of the protein mappings using the semantic similarity of their Gene Ontology annotations and observe that L-GRAAL best uncovers functionally conserved proteins. Furthermore, we introduce for the first time a measure of the semantic similarity of the mapped interactions and show that L-GRAAL also uncovers best functionally conserved interactions. In addition, we illustrate on the PPI networks of baker's yeast and human the ability of L-GRAAL to predict new PPIs. Finally, L-GRAAL's results are the first to show that topological information is more important than sequence information for uncovering functionally conserved interactions. L-GRAAL is coded in C++. Software is available at: http://bio-nets.doc.ic.ac.uk/L-GRAAL/. n.malod-dognin@imperial.ac.uk Supplementary data are available at

  13. Bridging Organizations Drive Effective Governance Outcomes for Conservation of Indonesia’s Marine Systems

    Science.gov (United States)

    Berdej, Samantha M.; Armitage, Derek R.

    2016-01-01

    This study empirically investigates the influence of bridging organizations on governance outcomes for marine conservation in Indonesia. Conservation challenges require ways of governing that are collaborative and adaptive across boundaries, and where conservation actions are better coordinated, information flows improved, and knowledge better integrated and mobilized. We combine quantitative social network analysis and qualitative data to analyze bridging organizations and their networks, and to understand their contributions and constraints in two case studies in Bali, Indonesia. The analysis shows 1) bridging organizations help to navigate the ‘messiness’ inherent in conservation settings by compensating for sparse linkages, 2) the particular structure and function of bridging organizations influence governing processes (i.e., collaboration, knowledge sharing) and subsequent conservation outcomes, 3) ‘bridging’ is accomplished using different strategies and platforms for collaboration and social learning, and 4) bridging organizations enhance flexibility to adjust to changing marine conservation contexts and needs. Understanding the organizations that occupy bridging positions, and how they utilize their positionality in a governance network is emerging as an important determinant of successful conservation outcomes. Our findings contribute to a relatively new body of literature on bridging organizations in marine conservation contexts, and add needed empirical investigation into their value to governance and conservation in Coral Triangle nations and beyond. PMID:26794003

  14. A conserved mammalian protein interaction network.

    Directory of Open Access Journals (Sweden)

    Åsa Pérez-Bercoff

    Full Text Available Physical interactions between proteins mediate a variety of biological functions, including signal transduction, physical structuring of the cell and regulation. While extensive catalogs of such interactions are known from model organisms, their evolutionary histories are difficult to study given the lack of interaction data from phylogenetic outgroups. Using phylogenomic approaches, we infer a upper bound on the time of origin for a large set of human protein-protein interactions, showing that most such interactions appear relatively ancient, dating no later than the radiation of placental mammals. By analyzing paired alignments of orthologous and putatively interacting protein-coding genes from eight mammals, we find evidence for weak but significant co-evolution, as measured by relative selective constraint, between pairs of genes with interacting proteins. However, we find no strong evidence for shared instances of directional selection within an interacting pair. Finally, we use a network approach to show that the distribution of selective constraint across the protein interaction network is non-random, with a clear tendency for interacting proteins to share similar selective constraints. Collectively, the results suggest that, on the whole, protein interactions in mammals are under selective constraint, presumably due to their functional roles.

  15. Climate change threatens European conservation areas

    DEFF Research Database (Denmark)

    Bastos Araujo, Miguel; Alagador, Diogo; Cabeza, Mar

    2011-01-01

    Europe has the world's most extensive network of conservation areas. Conservation areas are selected without taking into account the effects of climate change. How effectively would such areas conserve biodiversity under climate change? We assess the effectiveness of protected areas and the Natura...... 2000 network in conserving a large proportion of European plant and terrestrial vertebrate species under climate change. We found that by 2080, 58 ± 2.6% of the species would lose suitable climate in protected areas, whereas losses affected 63 ± 2.1% of the species of European concern occurring...

  16. Exploring effective conservation networks based on multi-scale planning unit analysis. A case study of the Balsas sub-basin, Maranhao State, Brazil

    NARCIS (Netherlands)

    Barreto, L.; Ribeiro, M.C.; Veldkamp, A.; Eupen, van M.; Kok, K.; Pontes, E.

    2010-01-01

    Nature conservation and restoration activities require delineation of effective conservation networks. This paper presents a methodology which allows a quick evaluation of different planning options for extensive areas. We analyzed the spatial structure of remaining patches of the natural Cerrado

  17. Ageing research on vertebrates shows knowledge gaps and opportunities for species conservation and management

    DEFF Research Database (Denmark)

    Conde, Dalia Amor

    is constant when species reach maturity. The implications of these assumptions have strong consequences not only in the development of evolutionary theories of ageing and population ecology but also in species conservation. By modeling mortality of different species of vertebrates we show that different...... models are needed to explore the diversity of mortality trajectories in animals. However, our state of demographic knowledge even for vertebrates is by far deficient to incorporate the effects on age. Exploring 13 available datasets on vertebrate life histories traits, our results show surprising figures...

  18. The Important Bird Areas Program in the United States: building a network of sites for conservation, state by state

    Science.gov (United States)

    Jeffrey V. Wells; Daniel K. Niven; John Cecil

    2005-01-01

    The Important Bird Area (IBA) program is an international effort to identify, conserve, and monitor a network of sites that provide essential habitat for bird populations. BirdLife International began the IBA program in Europe in 1985. Since that time, BirdLife partners in more than 100 countries have joined together to build the global IBA network. Audubon (BirdLife...

  19. Evolution of a protein domain interaction network

    International Nuclear Information System (INIS)

    Li-Feng, Gao; Jian-Jun, Shi; Shan, Guan

    2010-01-01

    In this paper, we attempt to understand complex network evolution from the underlying evolutionary relationship between biological organisms. Firstly, we construct a Pfam domain interaction network for each of the 470 completely sequenced organisms, and therefore each organism is correlated with a specific Pfam domain interaction network; secondly, we infer the evolutionary relationship of these organisms with the nearest neighbour joining method; thirdly, we use the evolutionary relationship between organisms constructed in the second step as the evolutionary course of the Pfam domain interaction network constructed in the first step. This analysis of the evolutionary course shows: (i) there is a conserved sub-network structure in network evolution; in this sub-network, nodes with lower degree prefer to maintain their connectivity invariant, and hubs tend to maintain their role as a hub is attached preferentially to new added nodes; (ii) few nodes are conserved as hubs; most of the other nodes are conserved as one with very low degree; (iii) in the course of network evolution, new nodes are added to the network either individually in most cases or as clusters with relative high clustering coefficients in a very few cases. (general)

  20. Minimizing species extinctions through strategic planning for conservation fencing.

    Science.gov (United States)

    Ringma, Jeremy L; Wintle, Brendan; Fuller, Richard A; Fisher, Diana; Bode, Michael

    2017-10-01

    Conservation fences are an increasingly common management action, particularly for species threatened by invasive predators. However, unlike many conservation actions, fence networks are expanding in an unsystematic manner, generally as a reaction to local funding opportunities or threats. We conducted a gap analysis of Australia's large predator-exclusion fence network by examining translocation of Australian mammals relative to their extinction risk. To address gaps identified in species representation, we devised a systematic prioritization method for expanding the conservation fence network that explicitly incorporated population viability analysis and minimized expected species' extinctions. The approach was applied to New South Wales, Australia, where the state government intends to expand the existing conservation fence network. Existing protection of species in fenced areas was highly uneven; 67% of predator-sensitive species were unrepresented in the fence network. Our systematic prioritization yielded substantial efficiencies in that it reduced expected number of species extinctions up to 17 times more effectively than ad hoc approaches. The outcome illustrates the importance of governance in coordinating management action when multiple projects have similar objectives and rely on systematic methods rather than expanding networks opportunistically. © 2017 Society for Conservation Biology.

  1. Setting conservation priorities for migratory networks under uncertainty.

    Science.gov (United States)

    Dhanjal-Adams, Kiran L; Klaassen, Marcel; Nicol, Sam; Possingham, Hugh P; Chadès, Iadine; Fuller, Richard A

    2017-06-01

    Conserving migratory species requires protecting connected habitat along the pathways they travel. Despite recent improvements in tracking animal movements, migratory connectivity remains poorly resolved at a population level for the vast majority of species, thus conservation prioritization is hampered. To address this data limitation, we developed a novel approach to spatial prioritization based on a model of potential connectivity derived from empirical data on species abundance and distance traveled between sites during migration. We applied the approach to migratory shorebirds of the East Asian-Australasian Flyway. Conservation strategies that prioritized sites based on connectivity and abundance metrics together maintained larger populations of birds than strategies that prioritized sites based only on abundance metrics. The conservation value of a site therefore depended on both its capacity to support migratory animals and its position within the migratory pathway; the loss of crucial sites led to partial or total population collapse. We suggest that conservation approaches that prioritize sites supporting large populations of migrants should, where possible, also include data on the spatial arrangement of sites. © 2016 Society for Conservation Biology.

  2. CUFID-query: accurate network querying through random walk based network flow estimation.

    Science.gov (United States)

    Jeong, Hyundoo; Qian, Xiaoning; Yoon, Byung-Jun

    2017-12-28

    Functional modules in biological networks consist of numerous biomolecules and their complicated interactions. Recent studies have shown that biomolecules in a functional module tend to have similar interaction patterns and that such modules are often conserved across biological networks of different species. As a result, such conserved functional modules can be identified through comparative analysis of biological networks. In this work, we propose a novel network querying algorithm based on the CUFID (Comparative network analysis Using the steady-state network Flow to IDentify orthologous proteins) framework combined with an efficient seed-and-extension approach. The proposed algorithm, CUFID-query, can accurately detect conserved functional modules as small subnetworks in the target network that are expected to perform similar functions to the given query functional module. The CUFID framework was recently developed for probabilistic pairwise global comparison of biological networks, and it has been applied to pairwise global network alignment, where the framework was shown to yield accurate network alignment results. In the proposed CUFID-query algorithm, we adopt the CUFID framework and extend it for local network alignment, specifically to solve network querying problems. First, in the seed selection phase, the proposed method utilizes the CUFID framework to compare the query and the target networks and to predict the probabilistic node-to-node correspondence between the networks. Next, the algorithm selects and greedily extends the seed in the target network by iteratively adding nodes that have frequent interactions with other nodes in the seed network, in a way that the conductance of the extended network is maximally reduced. Finally, CUFID-query removes irrelevant nodes from the querying results based on the personalized PageRank vector for the induced network that includes the fully extended network and its neighboring nodes. Through extensive

  3. Networking for conservation: social capital and perceptions of organizational success among land trust boards

    Directory of Open Access Journals (Sweden)

    Tatyana B. Ruseva

    2016-06-01

    Full Text Available As an important component in collaborative natural resource management and nonprofit governance, social capital is expected to be related to variations in the performance of land trusts. Land trusts are charitable organizations that work to conserve private land locally, regionally, or nationally. The purpose of this paper is to identify the level of structural and cognitive social capital among local land trusts, and how these two types of social capital relate to the perceived success of land trusts. The analysis integrates data for land trusts operating in the U.S. south-central Appalachian region, which includes western North Carolina, southwest Virginia, and east Tennessee. We use factor analysis to elicit different dimensions of cognitive social capital, including cooperation among board members, shared values, common norms, and communication effectiveness. Measures of structural social capital include the size and diversity of organizational networks of both land trusts and their board members. Finally, a hierarchical linear regression model is employed to estimate how cognitive and structural social capital measures, along with other organizational and individual-level attributes, relate to perceptions of land trust success, defined here as achievement of the land trusts' mission, conservation, and financial goals. Results show that the diversity of organizational partnerships, cooperation, and shared values among land trust board members are associated with higher levels of perceived success. Organizational capacity, land trust accreditation, volunteerism, and financial support are also important factors influencing perceptions of success among local, nonprofit land trusts.

  4. Mobility-Aware and Load Balancing Based Clustering Algorithm for Energy Conservation in MANET

    Institute of Scientific and Technical Information of China (English)

    XU Li; ZHENG Bao-yu; GUO Gong-de

    2005-01-01

    Mobile ad hoc network (MANET) is one of wireless communication network architecture that has received a lot of attention. MANET is characterized by dynamic network topology and limited energy. With mobility-aware and load balancing based clustering algorithm (MLCA), this paper proposes a new topology management strategy to conserve energy. Performance simulation results show that the proposed MLCA strategy can balances the traffic load inside the whole network, so as to prolong the network lifetime, meanly, at the same time, achieve higher throughput ratio and network stability.

  5. Transaction costs economics of irreplaceability: ex ante and ex post evaluation of conservation networks' vulnerability to environmental shocks.

    Science.gov (United States)

    Huusom, Henrik; Strange, Niels

    2008-04-01

    The theoretical concept, "asset specificity," is applied to real data in the context of Danish nature conservation network planning in order to produce illustrative examples of an economic measure of the network's vulnerability to exogenous shocks to the species composition. Three different measures of asset specificity are quantified from the shadow value of eliminating a key species from the individual grid cells. This represents a novel approach and a different interpretation of the term, as it is conventionally used as a qualitative indicator in the transaction cost economics literature. Apart from supplementing existing cost measures with an indicator of risk associated with investments in protected areas, this study demonstrates how the estimation and interpretation of various asset specificity measures for geographical areas may qualify policy makers' choice of policy instrument in conservation planning. This differs from the more intuitive approach of basing policy instrument choice solely on the rarity of the species in a given area.

  6. Conservation in Saudi Arabia; moving from strategy to practice.

    Science.gov (United States)

    Barichievy, Chris; Sheldon, Rob; Wacher, Tim; Llewellyn, Othman; Al-Mutairy, Mohammed; Alagaili, Abdulaziz

    2018-02-01

    Conservation in the Kingdom of Saudi Arabia is relatively young, yet have made considerable gains in conservation through strategic proclamation and reintroductions. Changes in land use, illegal hunting and competition with domestic stock has decimated the native ungulates, meaning that the survival of the native ungulate species is now completely dependent on protected area network. The challenge is to sustain this network to make meaningful conservation impact into the future. We review the status of ungulate conservation in Saudi Arabia and highlight that the conservation strategy is well developed. The major challenge faced in conservation in Saudi Arabia now is to implement what has been sanctioned.

  7. Pyrenean meadows in Natura 2000 network: grass production and plant biodiversity conservation

    Energy Technology Data Exchange (ETDEWEB)

    Reine, R.; Barrantes, O.; Chocarro, C.; Juarez, A.; Broca, A.; Maestro, M.; Ferrer, C.

    2014-06-01

    In semi-natural mountain meadows, yield and forage quality must be reconciled with plant biodiversity conservation. This study was performed to analyze the relationships between these three parameters. To quantify plant biodiversity and pastoral value (PV), phyto sociological inventories were performed in 104 semi-natural meadows in the Central Spanish Pyrenees included in the Natura 2000 network. Forage yields were calculated and forage samples were analyzed for relative feed value (RFV). We identified two main types of meadows: (i) those that had more intensive management, relatively close to farm buildings, with little or no slope, dominated by grasses, with low plant biodiversity, high PV and yield, but low forage quality and (ii) those that had less intensive management, distant from farm buildings, on slopes, richer in other forbs, with high plant biodiversity and forage quality, but low PV and yield. Conservation policies should emphasize less intensive management practices to maintain plant diversity in the semi-natural meadows in the Pyrenees. The widespread view that other forbs have low nutritional value should be revised in future research. These species often are undervalued by the PV method, because their nutritional quality, digestibility and intake are poorly understood. (Author)

  8. A state-based national network for effective wildlife conservation

    Science.gov (United States)

    Meretsky, Vicky J.; Maguire, Lynn A.; Davis, Frank W.; Stoms, David M.; Scott, J. Michael; Figg, Dennis; Goble, Dale D.; Griffith, Brad; Henke, Scott E.; Vaughn, Jacqueline; Yaffee, Steven L.

    2012-01-01

    State wildlife conservation programs provide a strong foundation for biodiversity conservation in the United States, building on state wildlife action plans. However, states may miss the species that are at the most risk at rangewide scales, and threats such as novel diseases and climate change increasingly act at regional and national levels. Regional collaborations among states and their partners have had impressive successes, and several federal programs now incorporate state priorities. However, regional collaborations are uneven across the country, and no national counterpart exists to support efforts at that scale. A national conservation-support program could fill this gap and could work across the conservation community to identify large-scale conservation needs and support efforts to meet them. By providing important information-sharing and capacity-building services, such a program would advance collaborative conservation among the states and their partners, thus increasing both the effectiveness and the efficiency of conservation in the United States.

  9. KCNQ channels show conserved ethanol block and function in ethanol behaviour.

    Directory of Open Access Journals (Sweden)

    Sonia Cavaliere

    Full Text Available In humans, KCNQ2/3 channels form an M-current that regulates neuronal excitability, with mutations in these channels causing benign neonatal familial convulsions. The M-current is important in mechanisms of neural plasticity underlying associative memory and in the response to ethanol, with KCNQ controlling the release of dopamine after ethanol exposure. We show that dKCNQ is broadly expressed in the nervous system, with targeted reduction in neuronal KCNQ increasing neural excitability and KCNQ overexpression decreasing excitability and calcium signalling, consistent with KCNQ regulating the resting membrane potential and neural release as in mammalian neurons. We show that the single KCNQ channel in Drosophila (dKCNQ has similar electrophysiological properties to neuronal KCNQ2/3, including conserved acute sensitivity to ethanol block, with the fly channel (IC(50 = 19.8 mM being more sensitive than its mammalian ortholog (IC(50 = 42.1 mM. This suggests that the role of KCNQ in alcohol behaviour can be determined for the first time by using Drosophila. We present evidence that loss of KCNQ function in Drosophila increased sensitivity and tolerance to the sedative effects of ethanol. Acute activation of dopaminergic neurons by heat-activated TRP channel or KCNQ-RNAi expression produced ethanol hypersensitivity, suggesting that both act via a common mechanism involving membrane depolarisation and increased dopamine signalling leading to ethanol sedation.

  10. Vulnerability of dynamic genetic conservation units of forest trees in Europe to climate change.

    Science.gov (United States)

    Schueler, Silvio; Falk, Wolfgang; Koskela, Jarkko; Lefèvre, François; Bozzano, Michele; Hubert, Jason; Kraigher, Hojka; Longauer, Roman; Olrik, Ditte C

    2014-05-01

    A transnational network of genetic conservation units for forest trees was recently documented in Europe aiming at the conservation of evolutionary processes and the adaptive potential of natural or man-made tree populations. In this study, we quantified the vulnerability of individual conservation units and the whole network to climate change using climate favourability models and the estimated velocity of climate change. Compared to the overall climate niche of the analysed target species populations at the warm and dry end of the species niche are underrepresented in the network. However, by 2100, target species in 33-65 % of conservation units, mostly located in southern Europe, will be at the limit or outside the species' current climatic niche as demonstrated by favourabilities below required model sensitivities of 95%. The highest average decrease in favourabilities throughout the network can be expected for coniferous trees although they are mainly occurring within units in mountainous landscapes for which we estimated lower velocities of change. Generally, the species-specific estimates of favourabilities showed only low correlations to the velocity of climate change in individual units, indicating that both vulnerability measures should be considered for climate risk analysis. The variation in favourabilities among target species within the same conservation units is expected to increase with climate change and will likely require a prioritization among co-occurring species. The present results suggest that there is a strong need to intensify monitoring efforts and to develop additional conservation measures for populations in the most vulnerable units. Also, our results call for continued transnational actions for genetic conservation of European forest trees, including the establishment of dynamic conservation populations outside the current species distribution ranges within European assisted migration schemes. © 2013 John Wiley & Sons Ltd.

  11. Pyrenean meadows in Natura 2000 network: grass production and plant biodiversity conservation

    Directory of Open Access Journals (Sweden)

    Ramón Reiné

    2014-02-01

    Full Text Available In semi-natural mountain meadows, yield and forage quality must be reconciled with plant biodiversity conservation. This study was performed to analyze the relationships between these three parameters. To quantify plant biodiversity and pastoral value (PV, phytosociological inventories were performed in 104 semi-natural meadows in the Central Spanish Pyrenees included in the Natura 2000 network. Forage yields were calculated and forage samples were analyzed for relative feed value (RFV. We identified two main types of meadows: (i those that had “more intensive management,” relatively close to farm buildings, with little or no slope, dominated by grasses, with low plant biodiversity, high PV and yield, but low forage quality and (ii those that had “less intensive management,” distant from farm buildings, on slopes, richer in “other forbs”, with high plant biodiversity and forage quality, but low PV and yield. Conservation policies should emphasize less intensive management practices to maintain plant diversity in the semi-natural meadows in the Pyrenees. The widespread view that “other forbs” have low nutritional value should be revised in future research. These species often are undervalued by the PV method, because their nutritional quality, digestibility and intake are poorly understood.

  12. Aggrecan-based extracellular matrix shows unique cortical features and conserved subcortical principles of mammalian brain organization in the Madagascan lesser hedgehog tenrec (Echinops telfairi Martin, 1838).

    Science.gov (United States)

    Morawski, M; Brückner, G; Jäger, C; Seeger, G; Künzle, H; Arendt, T

    2010-02-03

    The Madagascan tenrecs (Afrotheria), an ancient mammalian clade, are characterized by unique brain anatomy. Striking features are an expanded paleocortex but a small and poorly differentiated neocortex devoid of a distinct granular layer IV. To investigate the organization of cortical areas we analyzed extracellular matrix components in perineuronal nets (PNs) using antibodies to aggrecan, lectin staining and hyaluronan-binding protein. Selected subcortical regions were studied to correlate the cortical patterns with features in evolutionary conserved systems. In the neocortex, paleocortex and hippocampus PNs were associated with nonpyramidal neurons. Quantitative analysis in the cerebral cortex revealed area-specific proportions and laminar distribution patterns of neurons ensheathed by PNs. Cortical PNs showed divergent structural phenotypes. Diffuse PNs forming a cotton wool-like perisomatic rim were characteristic of the paleocortex. These PNs were associated with a dense pericellular plexus of calretinin-immunoreactive fibres. Clearly contoured PNs were devoid of a calretinin-positive plexus and predominated in the neocortex and hippocampus. The organization of the extracellular matrix in subcortical nuclei followed the widely distributed mammalian type. We conclude that molecular properties of the aggrecan-based extracellular matrix are conserved during evolution of mammals; however, the matrix scaffold is adapted to specific wiring patterns of cortical and subcortical neuronal networks. Copyright 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. Social network analysis shows direct evidence for social transmission of tool use in wild chimpanzees.

    Directory of Open Access Journals (Sweden)

    Catherine Hobaiter

    2014-09-01

    Full Text Available Social network analysis methods have made it possible to test whether novel behaviors in animals spread through individual or social learning. To date, however, social network analysis of wild populations has been limited to static models that cannot precisely reflect the dynamics of learning, for instance, the impact of multiple observations across time. Here, we present a novel dynamic version of network analysis that is capable of capturing temporal aspects of acquisition--that is, how successive observations by an individual influence its acquisition of the novel behavior. We apply this model to studying the spread of two novel tool-use variants, "moss-sponging" and "leaf-sponge re-use," in the Sonso chimpanzee community of Budongo Forest, Uganda. Chimpanzees are widely considered the most "cultural" of all animal species, with 39 behaviors suspected as socially acquired, most of them in the domain of tool-use. The cultural hypothesis is supported by experimental data from captive chimpanzees and a range of observational data. However, for wild groups, there is still no direct experimental evidence for social learning, nor has there been any direct observation of social diffusion of behavioral innovations. Here, we tested both a static and a dynamic network model and found strong evidence that diffusion patterns of moss-sponging, but not leaf-sponge re-use, were significantly better explained by social than individual learning. The most conservative estimate of social transmission accounted for 85% of observed events, with an estimated 15-fold increase in learning rate for each time a novice observed an informed individual moss-sponging. We conclude that group-specific behavioral variants in wild chimpanzees can be socially learned, adding to the evidence that this prerequisite for culture originated in a common ancestor of great apes and humans, long before the advent of modern humans.

  14. Social network analysis shows direct evidence for social transmission of tool use in wild chimpanzees.

    Science.gov (United States)

    Hobaiter, Catherine; Poisot, Timothée; Zuberbühler, Klaus; Hoppitt, William; Gruber, Thibaud

    2014-09-01

    Social network analysis methods have made it possible to test whether novel behaviors in animals spread through individual or social learning. To date, however, social network analysis of wild populations has been limited to static models that cannot precisely reflect the dynamics of learning, for instance, the impact of multiple observations across time. Here, we present a novel dynamic version of network analysis that is capable of capturing temporal aspects of acquisition--that is, how successive observations by an individual influence its acquisition of the novel behavior. We apply this model to studying the spread of two novel tool-use variants, "moss-sponging" and "leaf-sponge re-use," in the Sonso chimpanzee community of Budongo Forest, Uganda. Chimpanzees are widely considered the most "cultural" of all animal species, with 39 behaviors suspected as socially acquired, most of them in the domain of tool-use. The cultural hypothesis is supported by experimental data from captive chimpanzees and a range of observational data. However, for wild groups, there is still no direct experimental evidence for social learning, nor has there been any direct observation of social diffusion of behavioral innovations. Here, we tested both a static and a dynamic network model and found strong evidence that diffusion patterns of moss-sponging, but not leaf-sponge re-use, were significantly better explained by social than individual learning. The most conservative estimate of social transmission accounted for 85% of observed events, with an estimated 15-fold increase in learning rate for each time a novice observed an informed individual moss-sponging. We conclude that group-specific behavioral variants in wild chimpanzees can be socially learned, adding to the evidence that this prerequisite for culture originated in a common ancestor of great apes and humans, long before the advent of modern humans.

  15. Modeling the impact of future development and public conservation orientation on landscape connectivity for conservation planning

    DEFF Research Database (Denmark)

    Lechner, Alex Mark; Brown, Greg; Raymond, Christopher Mark

    2015-01-01

    aspects of conservation planning. Objectives We present an approach for characterizing the potential effects of public conservation orientation and projected future development land use scenarios on landscape connectivity. Methods Using public participation GIS techniques (mail-based surveys linked...... to a mapping component), we classified spatially explicit conservation values and preferences into a conservation orientation index consisting of positive, negative, or neutral scores. Connectivity was then modeled using a least-cost path and graph-network approach for a range of conservation orientation...... and development scenarios in the Lower Hunter region, Australia. Scenarios were modelled through either adding vegetation (positive orientation) or removing vegetation (negative orientation, development). Results Scenarios that included positive conservation orientation link the isolated eastern and western...

  16. The Gauteng Conservation Plan: Planning for biodiversity in a rapidly urbanising province

    Directory of Open Access Journals (Sweden)

    Michèle F. Pfab

    2017-11-01

    Conclusion: The existing protected area network is inadequate for the conservation of biodiversity in Gauteng. The Gauteng Conservation Plan identifies a set of areas that are required to achieve conservation targets. It is important that identified areas currently not in the protected area network are protected either formally or through legislated land use management processes.

  17. Prioritizing conservation areas for coastal plant diversity under increasing urbanization.

    Science.gov (United States)

    Doxa, Aggeliki; Albert, Cécile Hélène; Leriche, Agathe; Saatkamp, Arne

    2017-10-01

    Coastal urban expansion will continue to drive further biodiversity losses, if conservation targets for coastal ecosystems are not defined and met. Prioritizing areas for future protected area networks is thus an urgent task in such urbanization-threatened ecosystems. Our aim is to quantify past and future losses of coastal vegetation priority areas due to urbanization and assess the effectiveness of the existing protected area network for conservation. We conduct a prioritization analysis, based on 82 coastal plants, including common and IUCN red list species, in a highly-urbanized but biotically diverse region, in South-Eastern France. We evaluate the role of protected areas, by taking into account both strict and multi-use areas. We assess the impact of past and future urbanization on high priority areas, by combining prioritization analyses and urbanization models. We show that half of the highly diverse areas have already been lost due to urbanization. Remaining top priority areas are also among the most exposed to future urban expansion. The effectiveness of the existing protected area (PA) network is only partial. While strict PAs coincide well with top priority areas, they only represent less than one third of priority areas. The effectiveness of multi-use PAs, such as the Natura 2000 network, also remains limited. Our approach highlights the impact of urbanization on plant conservation targets. By modelling urbanization, we manage to identify those areas where protection could be more efficient to limit further losses. We suggest to use our approach in the future to expand the PA network in order to achieve the 2020 Aichi biodiversity targets. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Promoting Effective Monitoring and Conservation through Online ...

    African Journals Online (AJOL)

    ... communicates major findings of submitted records to relevant authorities concerned with conservation and advocacy thus contributing to a much wider sharing and dissemination of important aspects while contributing to avifaunal conservation. Through networking the system provides a highly attractive and authoritative, ...

  19. Indicator taxa revisited: useful for conservation planning?

    DEFF Research Database (Denmark)

    Larsen, Frank Wugt; Bladt, Jesper; Rahbek, Carsten

    2009-01-01

    Aim:  Indicators for biodiversity are needed to facilitate the identification of complementary reserve networks for biodiversity conservation. One widely adopted approach is to use indicator taxa, i.e. a single taxon such as birds or butterflies, despite the ongoing debate regarding their usefuln......Aim:  Indicators for biodiversity are needed to facilitate the identification of complementary reserve networks for biodiversity conservation. One widely adopted approach is to use indicator taxa, i.e. a single taxon such as birds or butterflies, despite the ongoing debate regarding...

  20. Droplet networks with incorporated protein diodes show collective properties

    Science.gov (United States)

    Maglia, Giovanni; Heron, Andrew J.; Hwang, William L.; Holden, Matthew A.; Mikhailova, Ellina; Li, Qiuhong; Cheley, Stephen; Bayley, Hagan

    2009-07-01

    Recently, we demonstrated that submicrolitre aqueous droplets submerged in an apolar liquid containing lipid can be tightly connected by means of lipid bilayers to form networks. Droplet interface bilayers have been used for rapid screening of membrane proteins and to form asymmetric bilayers with which to examine the fundamental properties of channels and pores. Networks, meanwhile, have been used to form microscale batteries and to detect light. Here, we develop an engineered protein pore with diode-like properties that can be incorporated into droplet interface bilayers in droplet networks to form devices with electrical properties including those of a current limiter, a half-wave rectifier and a full-wave rectifier. The droplet approach, which uses unsophisticated components (oil, lipid, salt water and a simple pore), can therefore be used to create multidroplet networks with collective properties that cannot be produced by droplet pairs.

  1. Anatomical Network Analysis Shows Decoupling of Modular Lability and Complexity in the Evolution of the Primate Skull

    Science.gov (United States)

    Esteve-Altava, Borja; Boughner, Julia C.; Diogo, Rui; Villmoare, Brian A.; Rasskin-Gutman, Diego

    2015-01-01

    Modularity and complexity go hand in hand in the evolution of the skull of primates. Because analyses of these two parameters often use different approaches, we do not know yet how modularity evolves within, or as a consequence of, an also-evolving complex organization. Here we use a novel network theory-based approach (Anatomical Network Analysis) to assess how the organization of skull bones constrains the co-evolution of modularity and complexity among primates. We used the pattern of bone contacts modeled as networks to identify connectivity modules and quantify morphological complexity. We analyzed whether modularity and complexity evolved coordinately in the skull of primates. Specifically, we tested Herbert Simon’s general theory of near-decomposability, which states that modularity promotes the evolution of complexity. We found that the skulls of extant primates divide into one conserved cranial module and up to three labile facial modules, whose composition varies among primates. Despite changes in modularity, statistical analyses reject a positive feedback between modularity and complexity. Our results suggest a decoupling of complexity and modularity that translates to varying levels of constraint on the morphological evolvability of the primate skull. This study has methodological and conceptual implications for grasping the constraints that underlie the developmental and functional integration of the skull of humans and other primates. PMID:25992690

  2. Efficiency of protected areas in Amazon and Atlantic Forest conservation: A spatio-temporal view

    Science.gov (United States)

    Sobral-Souza, Thadeu; Vancine, Maurício Humberto; Ribeiro, Milton Cezar; Lima-Ribeiro, Matheus S.

    2018-02-01

    The Amazon and Atlantic Forest are considered the world's most biodiverse biomes. Human and climate change impacts are the principal drivers of species loss in both biomes, more severely in the Atlantic Forest. In response to species loss, the main conservation action is the creation of protected areas (PAs). Current knowledge and research on the PA network's conservation efficiency is scarce, and existing studies have mainly considered a past temporal view. In this study, we tested the efficiency of the current PA network to maintain climatically stable areas (CSAs) across the Amazon and Atlantic Forest. To this, we used an ecological niche modeling approach to biome and paleoclimatic simulations. We propose three categories of conservation priority areas for both biomes, considering CSAs, PAs and intact forest remnants. The biomes vary in their respective PA networks' protection efficiency. Regarding protect CSAs, the Amazon PA network is four times more efficient than the Atlantic Forest PA network. New conservation efforts in these two forest biomes require different approaches. We discussed the conservation actions that should be taken in each biome to increase the efficiency of the PA network, considering both the creation and expansion of PAs as well as restoration programs.

  3. Dynamic conservation of forest genetic resources in 33 European countries

    NARCIS (Netherlands)

    Lefevre, F.; Koskela, J.; Hubert, J.; Kraigher, H.; Longauer, R.; Olrik, D.C.; Vries, de S.M.G.

    2013-01-01

    Dynamic conservation of forest genetic resources (FGR) means maintaining the genetic diversity of trees within an evolutionary process and allowing generation turnover in the forest. We assessed the network of forests areas managed for the dynamic conservation of FGR (conservation units) across

  4. USDA Forest Service Roadless Areas: Potential Biodiversity Conservation Reserves

    Directory of Open Access Journals (Sweden)

    Colby Loucks

    2003-12-01

    Full Text Available In January 2001, approximately 23 x 106 ha of land in the U.S. National Forest System were slated to remain roadless and protected from timber extraction under the Final Roadless Conservation Rule. We examined the potential contributions of these areas to the conservation of biodiversity. Using GIS, we analyzed the concordance of inventoried roadless areas (IRAs with ecoregion-scale biological importance and endangered and imperiled species distributions on a scale of 1:24,000. We found that more than 25% of IRAs are located in globally or regionally outstanding ecoregions and that 77% of inventoried roadless areas have the potential to conserve threatened, endangered, or imperiled species. IRAs would increase the conservation reserve network containing these species by 156%. We further illustrate the conservation potential of IRAs by highlighting their contribution to the conservation of the grizzly bear (Ursos arctos, a wide-ranging carnivore. The area created by the addition of IRAs to the existing system of conservation reserves shows a strong concordance with grizzly bear recovery zones and habitat range. Based on these findings, we conclude that IRAs belonging to the U.S. Forest Service are one of the most important biotic areas in the nation, and that their status as roadless areas could have lasting and far-reaching effects for biodiversity conservation.

  5. What is a conservation actor?

    Directory of Open Access Journals (Sweden)

    Paul Jepson

    2011-01-01

    Full Text Available As a crisis-oriented discipline, conservation biology needs actions to understand the state of nature and thwart declines in biodiversity. Actors-traditionally individuals, institutions, and collectives-have been central to delivering such goals in practice. However, the definition of actors within the discipline has been narrow and their role in influencing conservation outcomes inadequately conceptualised. In this paper, we examine the question ′What is a conservation actor?′ Who or what creates the capacity to influence conservation values and actions? Drawing from theoretical developments in Actor-Network Theory and collective governance, we argue that the concept of an actor in conservation biology should be broadened to include non-humans, such as species and devices, because they have the agency and ability to influence project goals and outcomes. We illustrate this through four examples: the Asian elephant, International Union for Conservation of Nature red lists, the High Conservation Value approach, and an Integrated Conservation and Development Project. We argue that a broader conceptualisation of actors in conservation biology will produce new forms of understanding that could open up new areas of conservation research, enhance practice and draw attention to spheres of conservation activity that might require stronger oversight and governance.

  6. Integrating population genetics and conservation biology in the era of genomics.

    Science.gov (United States)

    Ouborg, N Joop

    2010-02-23

    As one of the final activities of the ESF-CONGEN Networking programme, a conference entitled 'Integrating Population Genetics and Conservation Biology' was held at Trondheim, Norway, from 23 to 26 May 2009. Conference speakers and poster presenters gave a display of the state-of-the-art developments in the field of conservation genetics. Over the five-year running period of the successful ESF-CONGEN Networking programme, much progress has been made in theoretical approaches, basic research on inbreeding depression and other genetic processes associated with habitat fragmentation and conservation issues, and with applying principles of conservation genetics in the conservation of many species. Future perspectives were also discussed in the conference, and it was concluded that conservation genetics is evolving into conservation genomics, while at the same time basic and applied research on threatened species and populations from a population genetic point of view continues to be emphasized.

  7. Core concepts of spatial prioritisation in systematic conservation planning.

    Science.gov (United States)

    Kukkala, Aija S; Moilanen, Atte

    2013-05-01

    Systematic conservation planning (SCP) is a field of conservation biology concerned with delivering on-the-ground actions that achieve conservation goals. It describes a set of operational models that cover both design and implementation of conservation, with a strong focus on mobilising the collective action typically required to implement conservation. SCP, as it was originally described, was composed of six different stages: collection of data, identification of conservation goals, evaluation of the existing protected area network, design of expansions, implementation of conservation action, and long-term maintenance of biodiversity in the network. Since then, the operational model has been expanded into several different variants. Conservation actions applied inside SCP include establishment and expansion of reserve networks and allocation of habitat restoration and management. Within the broader context of SCP, there is a fundamental biogeographic-economic analysis frequently called spatial conservation prioritisation or conservation assessment, which is used for identifying where important areas for biodiversity are and how conservation goals might be achieved efficiently. Here, we review the usage and meaning of the 12 biogeographic-economic core concepts of SCP: adequacy, complementarity, comprehensiveness, effectiveness, efficiency, flexibility, irreplaceability, replacement cost, representation, representativeness, threat, and vulnerability. Some of the concepts have clear definitions whereas others may have alternative and possibly conflicting definitions. With a comprehensive literature review literature, we elucidate the historical backgrounds of these concepts, the first definitions and usages, alternative later definitions, key applications, and prior reviews. This review reduces linguistic uncertainty in the application of SCP. Since SCP is a global activity with a multitude of different stakeholders involved, it is vital that those involved can

  8. Criticality is an emergent property of genetic networks that exhibit evolvability.

    Directory of Open Access Journals (Sweden)

    Christian Torres-Sosa

    Full Text Available Accumulating experimental evidence suggests that the gene regulatory networks of living organisms operate in the critical phase, namely, at the transition between ordered and chaotic dynamics. Such critical dynamics of the network permits the coexistence of robustness and flexibility which are necessary to ensure homeostatic stability (of a given phenotype while allowing for switching between multiple phenotypes (network states as occurs in development and in response to environmental change. However, the mechanisms through which genetic networks evolve such critical behavior have remained elusive. Here we present an evolutionary model in which criticality naturally emerges from the need to balance between the two essential components of evolvability: phenotype conservation and phenotype innovation under mutations. We simulated the Darwinian evolution of random Boolean networks that mutate gene regulatory interactions and grow by gene duplication. The mutating networks were subjected to selection for networks that both (i preserve all the already acquired phenotypes (dynamical attractor states and (ii generate new ones. Our results show that this interplay between extending the phenotypic landscape (innovation while conserving the existing phenotypes (conservation suffices to cause the evolution of all the networks in a population towards criticality. Furthermore, the networks produced by this evolutionary process exhibit structures with hubs (global regulators similar to the observed topology of real gene regulatory networks. Thus, dynamical criticality and certain elementary topological properties of gene regulatory networks can emerge as a byproduct of the evolvability of the phenotypic landscape.

  9. Cardiogenic induction of pluripotent stem cells streamlined through a conserved SDF-1/VEGF/BMP2 integrated network.

    Directory of Open Access Journals (Sweden)

    Anca Chiriac

    Full Text Available BACKGROUND: Pluripotent stem cells produce tissue-specific lineages through programmed acquisition of sequential gene expression patterns that function as a blueprint for organ formation. As embryonic stem cells respond concomitantly to diverse signaling pathways during differentiation, extraction of a pro-cardiogenic network would offer a roadmap to streamline cardiac progenitor output. METHODS AND RESULTS: To resolve gene ontology priorities within precursor transcriptomes, cardiogenic subpopulations were here generated according to either growth factor guidance or stage-specific biomarker sorting. Innate expression profiles were independently delineated through unbiased systems biology mapping, and cross-referenced to filter transcriptional noise unmasking a conserved progenitor motif (55 up- and 233 down-regulated genes. The streamlined pool of 288 genes organized into a core biological network that prioritized the "Cardiovascular Development" function. Recursive in silico deconvolution of the cardiogenic neighborhood and associated canonical signaling pathways identified a combination of integrated axes, CXCR4/SDF-1, Flk-1/VEGF and BMP2r/BMP2, predicted to synchronize cardiac specification. In vitro targeting of the resolved triad in embryoid bodies accelerated expression of Nkx2.5, Mef2C and cardiac-MHC, enhanced beating activity, and augmented cardiogenic yield. CONCLUSIONS: Transcriptome-wide dissection of a conserved progenitor profile thus revealed functional highways that coordinate cardiogenic maturation from a pluripotent ground state. Validating the bioinformatics algorithm established a strategy to rationally modulate cell fate, and optimize stem cell-derived cardiogenesis.

  10. A conserved hydrogen-bond network in the catalytic centre of animal glutaminyl cyclases is critical for catalysis.

    Science.gov (United States)

    Huang, Kai-Fa; Wang, Yu-Ruei; Chang, En-Cheng; Chou, Tsung-Lin; Wang, Andrew H-J

    2008-04-01

    QCs (glutaminyl cyclases; glutaminyl-peptide cyclotransferases, EC 2.3.2.5) catalyse N-terminal pyroglutamate formation in numerous bioactive peptides and proteins. The enzymes were reported to be involved in several pathological conditions such as amyloidotic disease, osteoporosis, rheumatoid arthritis and melanoma. The crystal structure of human QC revealed an unusual H-bond (hydrogen-bond) network in the active site, formed by several highly conserved residues (Ser(160), Glu(201), Asp(248), Asp(305) and His(319)), within which Glu(201) and Asp(248) were found to bind to substrate. In the present study we combined steady-state enzyme kinetic and X-ray structural analyses of 11 single-mutation human QCs to investigate the roles of the H-bond network in catalysis. Our results showed that disrupting one or both of the central H-bonds, i.e., Glu(201)...Asp(305) and Asp(248)...Asp(305), reduced the steady-state catalysis dramatically. The roles of these two COOH...COOH bonds on catalysis could be partly replaced by COOH...water bonds, but not by COOH...CONH(2) bonds, reminiscent of the low-barrier Asp...Asp H-bond in the active site of pepsin-like aspartic peptidases. Mutations on Asp(305), a residue located at the centre of the H-bond network, raised the K(m) value of the enzyme by 4.4-19-fold, but decreased the k(cat) value by 79-2842-fold, indicating that Asp(305) primarily plays a catalytic role. In addition, results from mutational studies on Ser(160) and His(319) suggest that these two residues might help to stabilize the conformations of Asp(248) and Asp(305) respectively. These data allow us to propose an essential proton transfer between Glu(201), Asp(305) and Asp(248) during the catalysis by animal QCs.

  11. Spatial relationship between climatic diversity and biodiversity conservation value.

    Science.gov (United States)

    Wang, Junjun; Wu, Ruidong; He, Daming; Yang, Feiling; Hu, Peijun; Lin, Shiwei; Wu, Wei; Diao, Yixin; Guo, Yang

    2018-06-04

    Capturing the full range of climatic diversity in a reserve network is expected to improve the resilience of biodiversity to climate change. Therefore, a study on systematic conservation planning for climatic diversity that explicitly or implicitly hypothesizes that regions with higher climatic diversity will support greater biodiversity is needed. However, little is known about the extent and generality of this hypothesis. This study utilized the case of Yunnan, southwest China, to quantitatively classify climatic units and modeled 4 climatic diversity indicators, including the variety of climatic units (VCU), rarity of climatic units (RCU), endemism of climatic units (ECU) and a composite index of climatic units (CICD). We used 5 reliable priority conservation area (PCA) schemes to represent the areas with high biodiversity conservation value. We then investigated the spatial relationships between the 4 climatic diversity indicators and the 5 PCA schemes and assessed the representation of climatic diversity within the existing nature reserves. The CICD exhibited the best performance for indicating high conservation value areas, followed by the ECU and RCU. However, contrary to conventional knowledge, VCU did not show a positive association with biodiversity conservation value. The rarer or more endemic climatic units tended to have higher reserve coverage than the more common units. However, only 28 units covering 10.5% of the land in Yunnan had more than 17% of their areas protected. In addition to climatic factors, topography and human disturbances also significantly affected the relationship between climatic diversity and biodiversity conservation value. This analysis suggests that climatic diversity can be an effective surrogate for establishing a more robust reserve network under climate change in Yunnan. Our study improves the understanding of the relationship between climatic diversity and biodiversity and helps build an evidence-based foundation for

  12. Optimising Transport in a Homogeneous Network

    OpenAIRE

    WEAIRE, DENIS LAWRENCE

    2004-01-01

    PUBLISHED Many situations in physics, biology, and engineering consist of the transport of some physical quantity through a network of narrow channels. The ability of a network to transport such a quantity in every direction can be described by the average conductivity associated with it. When the flow through each channel is conserved and derives from a potential function, we show that there exists an upper bound of the average conductivity and explicitly give the expression f...

  13. Optimizing transport in a homogeneous network

    OpenAIRE

    WEAIRE, DENIS LAWRENCE

    2004-01-01

    PUBLISHED Many situations in physics, biology, and engineering consist of the transport of some physical quantity through a network of narrow channels. The ability of a network to transport such a quantity in every direction can be described by the average conductivity associated with it. When the flow through each channel is conserved and derives from a potential function, we show that there exists an upper bound of the average conductivity and explicitly give the expression f...

  14. Compensatory Measures in European Nature Conservation Law

    Directory of Open Access Journals (Sweden)

    Geert Van Hoorick

    2014-05-01

    Full Text Available The Birds and Habitats Directives are the cornerstones of EU nature conservation law, aiming at the conservation of the Natura 2000 network, a network of protected sites under these directives, and the protection of species. The protection regime for these sites and species is not absolute: Member States may, under certain conditions, allow plans or projects that can have an adverse impact on nature. In this case compensatory measures can play an important role in safeguarding the Natura 2000 network and ensuring the survival of the protected species.This contribution analyses whether taking compensatory measures is always obligatory, and discusses the aim and the characteristics of compensatory measures, in relation to other kinds of measures such as mitigation measures, usual nature conservation measures, and former nature development measures, and to the assessment of the adverse impact caused by the plan or project and of the alternative solutions. The questions will be discussed in light of the contents of the legislation, the guidance and practice by the European Commission, (legal doctrine and case law, mainly of the Court of Justice of the European Union.

  15. Plant conservation progress in the United States

    Science.gov (United States)

    Kayri Havens; Andrea Kramer; Ed. Guerrant

    2017-01-01

    Effective national plant conservation has several basic needs, including: 1) accessible, up-to-date information on species distribution and rarity; 2) research and management capacity to mitigate the impact of threats that make plants rare; 3) effective networks for conserving species in situ and ex situ; 4) education and training to make sure the right people are...

  16. Evaluating the Effectiveness of Natura 2000 Network for Wolf Conservation: A Case-Study in Greece

    Science.gov (United States)

    Votsi, Nefta-Eleftheria P.; Zomeni, Maria S.; Pantis, J. D.

    2016-02-01

    The wolf ( Canis lupus) is used as a case study to rate Natura 2000 sites in Greece based on preferred wolf habitat characteristics and test whether the network is suitable for their conservation. Road density, agricultural area, site area, connectivity, food availability (i.e., presence of natural prey), and elevation in 237 sites are combined in a logistic regression model. The occurrence of the wolf's natural prey was the most prevalent factor determining wolf presence, followed by agricultural cover. Considering the current status of these features at N2K site level, most sites currently hosting wolves (85.7 %) have good or excellent prospects for the long-term presence of the wolf. On the contrary, 11 sites which now have wolves are predicted to be ineffective in keeping them in the future due to the absence of wild ungulates and their high agricultural coverage. Four sites with no wolf presence currently have excellent prospects to host wolves in the future. Roadless sites are a priority for protection and retaining their current condition is strongly suggested. The proposed approach aims to detect gaps in protection for the wolf and identify priority sites in need of mitigation actions. It can also assist the assessment of conservation policies in Greece and elsewhere toward accomplishing set goals in protected areas. By focusing on wolf protection, we hope to increase agencies' attention to deal with conservation effectiveness, especially in cases like Greece, where a number of sites are insufficiently known and protected and management measures are not properly implemented.

  17. Letting the managers manage: analyzing capacity to conserve biodiversity in a cross-border protected area network

    Directory of Open Access Journals (Sweden)

    Sarah Clement

    2016-09-01

    Full Text Available Biodiversity loss is one of the most significant drivers of ecosystem change and is projected to continue at a rapid rate. While protected areas, such as national parks, are seen as important refuges for biodiversity, their effectiveness in stemming biodiversity decline has been questioned. Public agencies have a critical role in the governance of many such areas, but there are tensions between the need for these agencies to be more "adaptive" and their current operating environment. Our aim is to analyze how institutions enable or constrain capacity to conserve biodiversity in a globally significant cross-border network of protected areas, the Australian Alps. Using a novel conceptual framework for diagnosing biodiversity institutions, our research examined institutional adaptive capacity and more general capacity for conserving biodiversity. Several intertwined issues limit public agencies' capacity to fulfill their conservation responsibilities. Narrowly defined accountability measures constrain adaptive capacity and divert attention away from addressing key biodiversity outcomes. Implications for learning were also evident, with protected area agencies demonstrating successful learning for on-ground issues but less success in applying this learning to deeper policy change. Poor capacity to buffer political and community influences in managing significant cross-border drivers of biodiversity decline signals poor fit with the institutional context and has implications for functional fit. While cooperative federalism provides potential benefits for buffering through diversity, it also means protected area agencies have restricted authority to address cross-border threats. Restrictions on staff authority and discretion, as public servants, have further implications for deploying capacity. This analysis, particularly the possibility of fostering "ambidexterity" - creatively responding to political pressures in a way that also achieves a desirable

  18. Not more, but strategic collaboration needed to conserve Borneo's orangutan

    Directory of Open Access Journals (Sweden)

    Courtney L. Morgans

    2017-07-01

    Full Text Available In conservation, Collaboration is thought to improve returns from investment and is frequently encouraged, however not all collaborations are equal and may therefore lack characteristics important for addressing collective action problems. Furthermore, partnerships that are advantageous for a collective may not necessarily be advantageous for an individual. This study investigated collaboration within the Bornean orangutan (Pongo pygmaeus conservation sector – a system with reported inefficiencies and for which there has been a renewed call for collaborative partnerships. Collaborative partnerships were conceptualised as a social network and analysed using exponential random graph modelling. The prevalence of structural attributes associated with social processes considered to be important for solving collective action problems such as trust and innovation were investigated. Qualitative surveying techniques were used to measure the perceptions of collaboration held by individual actors within the network and the impact of organizational attributes on network formation and perceptions was assessed. Collaboration was found to be occurring within the conservation network and was positively perceived at the individual organisational level. At the collective level, the current collaborative network contains some structural characteristics important for addressing the collective-action problem of orangutan conservation, particularly through innovation and knowledge sharing. However efforts to develop trust between organisations may be needed. To improve returns on investment, future collaborative partnerships must be strategically implemented with individual roles and desired overall outcomes explicitly articulated. Increased operational transparency and improved performance evaluation will be critical for achieving improved collaborative efficiency.

  19. Studies on a network of complex neurons

    Science.gov (United States)

    Chakravarthy, Srinivasa V.; Ghosh, Joydeep

    1993-09-01

    In the last decade, much effort has been directed towards understanding the role of chaos in the brain. Work with rabbits reveals that in the resting state the electrical activity on the surface of the olfactory bulb is chaotic. But, when the animal is involved in a recognition task, the activity shifts to a specific pattern corresponding to the odor that is being recognized. Unstable, quasiperiodic behavior can be found in a class of conservative, deterministic physical systems called the Hamiltonian systems. In this paper, we formulate a complex version of Hopfield's network of real parameters and show that a variation on this model is a conservative system. Conditions under which the complex network can be used as a Content Addressable memory are studied. We also examine the effect of singularities of the complex sigmoid function on the network dynamics. The network exhibits unpredictable behavior at the singularities due to the failure of a uniqueness condition for the solution of the dynamic equations. On incorporating a weight adaptation rule, the structure of the resulting complex network equations is shown to have an interesting similarity with Kosko's Adaptive Bidirectional Associative Memory.

  20. Combined Use of Systematic Conservation Planning, Species Distribution Modelling, and Connectivity Analysis Reveals Severe Conservation Gaps in a Megadiverse Country (Peru)

    Science.gov (United States)

    Fajardo, Javier; Lessmann, Janeth; Bonaccorso, Elisa; Devenish, Christian; Muñoz, Jesús

    2014-01-01

    Conservation planning is crucial for megadiverse countries where biodiversity is coupled with incomplete reserve systems and limited resources to invest in conservation. Using Peru as an example of a megadiverse country, we asked whether the national system of protected areas satisfies biodiversity conservation needs. Further, to complement the existing reserve system, we identified and prioritized potential conservation areas using a combination of species distribution modeling, conservation planning and connectivity analysis. Based on a set of 2,869 species, including mammals, birds, amphibians, reptiles, butterflies, and plants, we used species distribution models to represent species' geographic ranges to reduce the effect of biased sampling and partial knowledge about species' distributions. A site-selection algorithm then searched for efficient and complementary proposals, based on the above distributions, for a more representative system of protection. Finally, we incorporated connectivity among areas in an innovative post-hoc analysis to prioritize those areas maximizing connectivity within the system. Our results highlight severe conservation gaps in the Coastal and Andean regions, and we propose several areas, which are not currently covered by the existing network of protected areas. Our approach helps to find areas that contribute to creating a more representative, connected and efficient network. PMID:25479411

  1. Effective comparative analysis of protein-protein interaction networks by measuring the steady-state network flow using a Markov model.

    Science.gov (United States)

    Jeong, Hyundoo; Qian, Xiaoning; Yoon, Byung-Jun

    2016-10-06

    Comparative analysis of protein-protein interaction (PPI) networks provides an effective means of detecting conserved functional network modules across different species. Such modules typically consist of orthologous proteins with conserved interactions, which can be exploited to computationally predict the modules through network comparison. In this work, we propose a novel probabilistic framework for comparing PPI networks and effectively predicting the correspondence between proteins, represented as network nodes, that belong to conserved functional modules across the given PPI networks. The basic idea is to estimate the steady-state network flow between nodes that belong to different PPI networks based on a Markov random walk model. The random walker is designed to make random moves to adjacent nodes within a PPI network as well as cross-network moves between potential orthologous nodes with high sequence similarity. Based on this Markov random walk model, we estimate the steady-state network flow - or the long-term relative frequency of the transitions that the random walker makes - between nodes in different PPI networks, which can be used as a probabilistic score measuring their potential correspondence. Subsequently, the estimated scores can be used for detecting orthologous proteins in conserved functional modules through network alignment. Through evaluations based on multiple real PPI networks, we demonstrate that the proposed scheme leads to improved alignment results that are biologically more meaningful at reduced computational cost, outperforming the current state-of-the-art algorithms. The source code and datasets can be downloaded from http://www.ece.tamu.edu/~bjyoon/CUFID .

  2. European ecological networks and greenways

    DEFF Research Database (Denmark)

    Kristiansen, Ib; Jongman, Rob H.G.; Kulvik, Mart

    2004-01-01

    renewed. Within the framework of nature conservation, the notion of an ecological network has become increasingly important. Throughout Europe, regional and national approaches are in different phases of development, which are all based on recent landscape ecological principles. Ecological networks......In the context of European integration, networks are becoming increasingly important in both social and ecological sense. Since the beginning of the 1990s, societal and scientific exchanges are being restructured as the conceptual approaches towards new nature conservation strategies have been....... This complex interaction between cultural and natural features results in quite different ways for the elaboration of ecological networks and greenways....

  3. Fused Regression for Multi-source Gene Regulatory Network Inference.

    Directory of Open Access Journals (Sweden)

    Kari Y Lam

    2016-12-01

    Full Text Available Understanding gene regulatory networks is critical to understanding cellular differentiation and response to external stimuli. Methods for global network inference have been developed and applied to a variety of species. Most approaches consider the problem of network inference independently in each species, despite evidence that gene regulation can be conserved even in distantly related species. Further, network inference is often confined to single data-types (single platforms and single cell types. We introduce a method for multi-source network inference that allows simultaneous estimation of gene regulatory networks in multiple species or biological processes through the introduction of priors based on known gene relationships such as orthology incorporated using fused regression. This approach improves network inference performance even when orthology mapping and conservation are incomplete. We refine this method by presenting an algorithm that extracts the true conserved subnetwork from a larger set of potentially conserved interactions and demonstrate the utility of our method in cross species network inference. Last, we demonstrate our method's utility in learning from data collected on different experimental platforms.

  4. Resting-state networks associated with cognitive processing show more age-related decline than those associated with emotional processing.

    Science.gov (United States)

    Nashiro, Kaoru; Sakaki, Michiko; Braskie, Meredith N; Mather, Mara

    2017-06-01

    Correlations in activity across disparate brain regions during rest reveal functional networks in the brain. Although previous studies largely agree that there is an age-related decline in the "default mode network," how age affects other resting-state networks, such as emotion-related networks, is still controversial. Here we used a dual-regression approach to investigate age-related alterations in resting-state networks. The results revealed age-related disruptions in functional connectivity in all 5 identified cognitive networks, namely the default mode network, cognitive-auditory, cognitive-speech (or speech-related somatosensory), and right and left frontoparietal networks, whereas such age effects were not observed in the 3 identified emotion networks. In addition, we observed age-related decline in functional connectivity in 3 visual and 3 motor/visuospatial networks. Older adults showed greater functional connectivity in regions outside 4 out of the 5 identified cognitive networks, consistent with the dedifferentiation effect previously observed in task-based functional magnetic resonance imaging studies. Both reduced within-network connectivity and increased out-of-network connectivity were correlated with poor cognitive performance, providing potential biomarkers for cognitive aging. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Vulnerability of dynamic genetic conservation units of forest trees in Europe to climate change

    OpenAIRE

    Schueler, Silvio; Falk, Wolfgang; Koskela, Jarkko; Lefèvre, François; Bozzano, Michele; Hubert, Jason; Kraigher, Hojka; Longauer, Roman; Olrik, Ditte C.

    2014-01-01

    A transnational network of genetic conservation units for forest trees was recently documented in Europe aiming at the conservation of evolutionary processes and the adaptive potential of natural or man-made tree populations. In this study, we quantified the vulnerability of individual conservation units and the whole network to climate change using climate favourability models and the estimated velocity of climate change. Compared to the overall climate niche of the analysed target species p...

  6. Building Virtual Watersheds: A Global Opportunity to Strengthen Resource Management and Conservation

    Science.gov (United States)

    Benda, Lee; Miller, Daniel; Barquin, Jose; McCleary, Richard; Cai, TiJiu; Ji, Y.

    2016-03-01

    Modern land-use planning and conservation strategies at landscape to country scales worldwide require complete and accurate digital representations of river networks, encompassing all channels including the smallest headwaters. The digital river networks, integrated with widely available digital elevation models, also need to have analytical capabilities to support resource management and conservation, including attributing river segments with key stream and watershed data, characterizing topography to identify landforms, discretizing land uses at scales necessary to identify human-environment interactions, and connecting channels downstream and upstream, and to terrestrial environments. We investigate the completeness and analytical capabilities of national to regional scale digital river networks that are available in five countries: Canada, China, Russia, Spain, and United States using actual resource management and conservation projects involving 12 university, agency, and NGO organizations. In addition, we review one pan-European and one global digital river network. Based on our analysis, we conclude that the majority of the regional, national, and global scale digital river networks in our sample lack in network completeness, analytical capabilities or both. To address this limitation, we outline a general framework to build as complete as possible digital river networks and to integrate them with available digital elevation models to create robust analytical capabilities (e.g., virtual watersheds). We believe this presents a global opportunity for in-country agencies, or international players, to support creation of virtual watersheds to increase environmental problem solving, broaden access to the watershed sciences, and strengthen resource management and conservation in countries worldwide.

  7. Characterizing Species at Risk II: Using Bayesian Belief Networks as Decision Support Tools to Determine Species Conservation Categories Under the Northwest Forest Plan

    Directory of Open Access Journals (Sweden)

    Bruce G. Marcot

    2006-12-01

    Full Text Available We developed a set of decision-aiding models as Bayesian belief networks (BBNs that represented a complex set of evaluation guidelines used to determine the appropriate conservation of hundreds of potentially rare species on federally-administered lands in the Pacific Northwest United States. The models were used in a structured assessment and paneling procedure as part of an adaptive management process that evaluated new scientific information under the Northwest Forest Plan. The models were not prescriptive but helped resource managers and specialists to evaluate complicated and at times conflicting conservation guidelines and to reduce bias and uncertainty in evaluating the scientific data. We concluded that applying the BBN modeling framework to complex and equivocal evaluation guidelines provided a set of clear, intuitive decision-aiding tools that greatly aided the species evaluation and conservation process.

  8. Algebraic connectivity of brain networks shows patterns of segregation leading to reduced network robustness in Alzheimer's disease

    Science.gov (United States)

    Daianu, Madelaine; Jahanshad, Neda; Nir, Talia M.; Leonardo, Cassandra D.; Jack, Clifford R.; Weiner, Michael W.; Bernstein, Matthew A.; Thompson, Paul M.

    2015-01-01

    Measures of network topology and connectivity aid the understanding of network breakdown as the brain degenerates in Alzheimer's disease (AD). We analyzed 3-Tesla diffusion-weighted images from 202 patients scanned by the Alzheimer's Disease Neuroimaging Initiative – 50 healthy controls, 72 with early- and 38 with late-stage mild cognitive impairment (eMCI/lMCI) and 42 with AD. Using whole-brain tractography, we reconstructed structural connectivity networks representing connections between pairs of cortical regions. We examined, for the first time in this context, the network's Laplacian matrix and its Fiedler value, describing the network's algebraic connectivity, and the Fiedler vector, used to partition a graph. We assessed algebraic connectivity and four additional supporting metrics, revealing a decrease in network robustness and increasing disarray among nodes as dementia progressed. Network components became more disconnected and segregated, and their modularity increased. These measures are sensitive to diagnostic group differences, and may help understand the complex changes in AD. PMID:26640830

  9. Genomic dissection of conserved transcriptional regulation in intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Colin R Lickwar

    2017-08-01

    Full Text Available The intestinal epithelium serves critical physiologic functions that are shared among all vertebrates. However, it is unknown how the transcriptional regulatory mechanisms underlying these functions have changed over the course of vertebrate evolution. We generated genome-wide mRNA and accessible chromatin data from adult intestinal epithelial cells (IECs in zebrafish, stickleback, mouse, and human species to determine if conserved IEC functions are achieved through common transcriptional regulation. We found evidence for substantial common regulation and conservation of gene expression regionally along the length of the intestine from fish to mammals and identified a core set of genes comprising a vertebrate IEC signature. We also identified transcriptional start sites and other putative regulatory regions that are differentially accessible in IECs in all 4 species. Although these sites rarely showed sequence conservation from fish to mammals, surprisingly, they drove highly conserved IEC expression in a zebrafish reporter assay. Common putative transcription factor binding sites (TFBS found at these sites in multiple species indicate that sequence conservation alone is insufficient to identify much of the functionally conserved IEC regulatory information. Among the rare, highly sequence-conserved, IEC-specific regulatory regions, we discovered an ancient enhancer upstream from her6/HES1 that is active in a distinct population of Notch-positive cells in the intestinal epithelium. Together, these results show how combining accessible chromatin and mRNA datasets with TFBS prediction and in vivo reporter assays can reveal tissue-specific regulatory information conserved across 420 million years of vertebrate evolution. We define an IEC transcriptional regulatory network that is shared between fish and mammals and establish an experimental platform for studying how evolutionarily distilled regulatory information commonly controls IEC development

  10. Applying network theory to prioritize multispecies habitat networks that are robust to climate and land-use change.

    Science.gov (United States)

    Albert, Cécile H; Rayfield, Bronwyn; Dumitru, Maria; Gonzalez, Andrew

    2017-12-01

    Designing connected landscapes is among the most widespread strategies for achieving biodiversity conservation targets. The challenge lies in simultaneously satisfying the connectivity needs of multiple species at multiple spatial scales under uncertain climate and land-use change. To evaluate the contribution of remnant habitat fragments to the connectivity of regional habitat networks, we developed a method to integrate uncertainty in climate and land-use change projections with the latest developments in network-connectivity research and spatial, multipurpose conservation prioritization. We used land-use change simulations to explore robustness of species' habitat networks to alternative development scenarios. We applied our method to 14 vertebrate focal species of periurban Montreal, Canada. Accounting for connectivity in spatial prioritization strongly modified conservation priorities and the modified priorities were robust to uncertain climate change. Setting conservation priorities based on habitat quality and connectivity maintained a large proportion of the region's connectivity, despite anticipated habitat loss due to climate and land-use change. The application of connectivity criteria alongside habitat-quality criteria for protected-area design was efficient with respect to the amount of area that needs protection and did not necessarily amplify trade-offs among conservation criteria. Our approach and results are being applied in and around Montreal and are well suited to the design of ecological networks and green infrastructure for the conservation of biodiversity and ecosystem services in other regions, in particular regions around large cities, where connectivity is critically low. © 2017 Society for Conservation Biology.

  11. Frequency Assignment, Sharing and Conservation in Systems (Aerospace). (l’Attribution, le partage et la conservation des frequences pour les systemes aeronautiques et spatiales)

    Science.gov (United States)

    1999-01-01

    NETWORKS C. Bousofto-Calzön A.R. Figueiras-Vidal Dpto. Tecnologias de las Comunicaciones Univ. Carlos III de Madrid C/Butarque, 15; 28911 Leganes...Attribution, le partage et la conservation des frequences pour les systemes aeronautiques et spatiales) Papers presented at the Information Systems...PROCEEDINGS 13 Frequency Assignment, Sharing and Conservation in Systems (Aerospace) (V Attribution, le partage et la conservation des frequences pour

  12. Network switching strategy for energy conservation in heterogeneous networks.

    Directory of Open Access Journals (Sweden)

    Yujae Song

    Full Text Available In heterogeneous networks (HetNets, the large-scale deployment of small base stations (BSs together with traditional macro BSs is an economical and efficient solution that is employed to address the exponential growth in mobile data traffic. In dense HetNets, network switching, i.e., handovers, plays a critical role in connecting a mobile terminal (MT to the best of all accessible networks. In the existing literature, a handover decision is made using various handover metrics such as the signal-to-noise ratio, data rate, and movement speed. However, there are few studies on handovers that focus on energy efficiency in HetNets. In this paper, we propose a handover strategy that helps to minimize energy consumption at BSs in HetNets without compromising the quality of service (QoS of each MT. The proposed handover strategy aims to capture the effect of the stochastic behavior of handover parameters and the expected energy consumption due to handover execution when making a handover decision. To identify the validity of the proposed handover strategy, we formulate a handover problem as a constrained Markov decision process (CMDP, by which the effects of the stochastic behaviors of handover parameters and consequential handover energy consumption can be accurately reflected when making a handover decision. In the CMDP, the aim is to minimize the energy consumption to service an MT over the lifetime of its connection, and the constraint is to guarantee the QoS requirements of the MT given in terms of the transmission delay and call-dropping probability. We find an optimal policy for the CMDP using a combination of the Lagrangian method and value iteration. Simulation results verify the validity of the proposed handover strategy.

  13. Conserved host-pathogen PPIs. Globally conserved inter-species bacterial PPIs based conserved host-pathogen interactome derived novel target in C. pseudotuberculosis, C. diphtheriae, M. tuberculosis, C. ulcerans, Y. pestis, and E. coli targeted by Piper betel compounds

    DEFF Research Database (Denmark)

    Barh, Debmalya; Gupta, Krishnakant; Jain, Neha

    2013-01-01

    of Caseous Lymphadenitis (CLA). In this study, we used computational approaches to develop common conserved intra-species protein-protein interaction (PPI) networks first time for four Cp strains (Cp FRC41, Cp 316, Cp 3/99-5, and Cp P54B96) followed by development of a common conserved inter...

  14. Conservation, spillover and gene flow within a network of Northern European marine protected areas.

    Directory of Open Access Journals (Sweden)

    Mats Brockstedt Olsen Huserbråten

    Full Text Available To ensure that marine protected areas (MPAs benefit conservation and fisheries, the effectiveness of MPA designs has to be evaluated in field studies. Using an interdisciplinary approach, we empirically assessed the design of a network of northern MPAs where fishing for European lobster (Homarusgammarus is prohibited. First, we demonstrate a high level of residency and survival (50% for almost a year (363 days within MPAs, despite small MPA sizes (0.5-1 km(2. Second, we demonstrate limited export (4.7% of lobsters tagged within MPAs (N = 1810 to neighbouring fished areas, over a median distance of 1.6 km out to maximum 21 km away from MPA centres. In comparison, median movement distance of lobsters recaptured within MPAs was 164 m, and recapture rate was high (40%. Third, we demonstrate a high level of gene flow within the study region, with an estimated F ST of less than 0.0001 over a ≈ 400 km coastline. Thus, the restricted movement of older life stages, combined with a high level of gene flow suggests that connectivity is primarily driven by larval drift. Larval export from the MPAs can most likely affect areas far beyond their borders. Our findings are of high importance for the design of MPA networks for sedentary species with pelagic early life stages.

  15. Conservation of gene co-regulation in prokaryotes and eukaryotes.

    NARCIS (Netherlands)

    Snel, B.; Bork, P.; Huynen, M.A.

    2002-01-01

    We raise some issues in detecting the conservation (or absence thereof) of co-regulation using gene order; how we think the variations in the cellular network in various species can be studied; and how to determine and interpret the higher order structure in networks of functional relations.

  16. Leadership: a new frontier in conservation science.

    Science.gov (United States)

    Manolis, Jim C; Chan, Kai M; Finkelstein, Myra E; Stephens, Scott; Nelson, Cara R; Grant, Jacqualine B; Dombeck, Michael P

    2009-08-01

    Leadership is a critical tool for expanding the influence of conservation science, but recent advances in leadership concepts and practice remain underutilized by conservation scientists. Furthermore, an explicit conceptual foundation and definition of leadership in conservation science are not available in the literature. Here we drew on our diverse leadership experiences, our reading of leadership literature, and discussions with selected conservation science leaders to define conservation-science leadership, summarize an exploratory set of leadership principles that are applicable to conservation science, and recommend actions to expand leadership capacity among conservation scientists and practitioners. We define 2 types of conservation-science leadership: shaping conservation science through path-breaking research, and advancing the integration of conservation science into policy, management, and society at large. We focused on the second, integrative type of leadership because we believe it presents the greatest opportunity for improving conservation effectiveness. We identified 8 leadership principles derived mainly from the "adaptive leadership" literature: recognize the social dimension of the problem; cycle frequently through action and reflection; get and maintain attention; combine strengths of multiple leaders; extend your reach through networks of relationships; strategically time your effort; nurture productive conflict; and cultivate diversity. Conservation scientists and practitioners should strive to develop themselves as leaders, and the Society for Conservation Biology, conservation organizations, and academia should support this effort through professional development, mentoring, teaching, and research.

  17. The CRC orthologue from Pisum sativum shows conserved functions in carpel morphogenesis and vascular development.

    Science.gov (United States)

    Fourquin, Chloé; Primo, Amparo; Martínez-Fernández, Irene; Huet-Trujillo, Estefanía; Ferrándiz, Cristina

    2014-11-01

    CRABS CLAW (CRC) is a member of the YABBY family of transcription factors involved in carpel morphogenesis, floral determinacy and nectary specification in arabidopsis. CRC orthologues have been functionally characterized across angiosperms, revealing additional roles in leaf vascular development and carpel identity specification in Poaceae. These studies support an ancestral role of CRC orthologues in carpel development, while roles in vascular development and nectary specification appear to be derived. This study aimed to expand research on CRC functional conservation to the legume family in order to better understand the evolutionary history of CRC orthologues in angiosperms. CRC orthologues from Pisum sativum and Medicago truncatula were identified. RNA in situ hybridization experiments determined the corresponding expression patterns throughout flower development. The phenotypic effects of reduced CRC activity were investigated in P. sativum using virus-induced gene silencing. CRC orthologues from P. sativum and M. truncatula showed similar expression patterns, mainly restricted to carpels and nectaries. However, these expression patterns differed from those of other core eudicots, most importantly in a lack of abaxial expression in the carpel and in atypical expression associated with the medial vein of the ovary. CRC downregulation in pea caused defects in carpel fusion and style/stigma development, both typically associated with CRC function in eudicots, but also affected vascular development in the carpel. The data support the conserved roles of CRC orthologues in carpel fusion, style/stigma development and nectary development. In addition, an intriguing new aspect of CRC function in legumes was the unexpected role in vascular development, which could be shared by other species from widely diverged clades within the angiosperms, suggesting that this role could be ancestral rather than derived, as so far generally accepted. © The Author 2014. Published by

  18. Flux networks in metabolic graphs

    International Nuclear Information System (INIS)

    Warren, P B; Queiros, S M Duarte; Jones, J L

    2009-01-01

    A metabolic model can be represented as a bipartite graph comprising linked reaction and metabolite nodes. Here it is shown how a network of conserved fluxes can be assigned to the edges of such a graph by combining the reaction fluxes with a conserved metabolite property such as molecular weight. A similar flux network can be constructed by combining the primal and dual solutions to the linear programming problem that typically arises in constraint-based modelling. Such constructions may help with the visualization of flux distributions in complex metabolic networks. The analysis also explains the strong correlation observed between metabolite shadow prices (the dual linear programming variables) and conserved metabolite properties. The methods were applied to recent metabolic models for Escherichia coli, Saccharomyces cerevisiae and Methanosarcina barkeri. Detailed results are reported for E. coli; similar results were found for other organisms

  19. Energy efficiency networks; Energieeffizienz-Netzwerke

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, Anna [Forschungsgesellschaft fuer Energiewirtschaft mbH (FfE GmbH), Muenchen (Germany)

    2011-07-01

    Energy efficiency networks are an attractive method to increase the energy efficiency and to reduce the costs and CO{sub 2} emissions of the companies operating in this network. A special feature of the energy efficiency networks is the exchange of experiences and training of the energy managers. Energy efficiency networks consist of about ten to fifteen locally domiciled companies. During the project period of three to four years, there are two main phases. In the first phase, the initial consultation phase, the actual state of a company is captured, and measures to increase the efficiency and energy conservation are identified. Parallel to this, in the second phase every three months a meeting with the participating companies takes place. Experience exchange and implementation of energy efficiency measures are the focus of these meetings. Initial studies show that the increase of the energy efficiency during participating in the energy efficiency network almost can be doubled in comparison to the average of the industry.

  20. Delay-independent stability of genetic regulatory networks.

    Science.gov (United States)

    Wu, Fang-Xiang

    2011-11-01

    Genetic regulatory networks can be described by nonlinear differential equations with time delays. In this paper, we study both locally and globally delay-independent stability of genetic regulatory networks, taking messenger ribonucleic acid alternative splicing into consideration. Based on nonnegative matrix theory, we first develop necessary and sufficient conditions for locally delay-independent stability of genetic regulatory networks with multiple time delays. Compared to the previous results, these conditions are easy to verify. Then we develop sufficient conditions for global delay-independent stability for genetic regulatory networks. Compared to the previous results, this sufficient condition is less conservative. To illustrate theorems developed in this paper, we analyze delay-independent stability of two genetic regulatory networks: a real-life repressilatory network with three genes and three proteins, and a synthetic gene regulatory network with five genes and seven proteins. The simulation results show that the theorems developed in this paper can effectively determine the delay-independent stability of genetic regulatory networks.

  1. A survey of energy conservation mechanisms for dynamic cluster based wireless sensor networks

    International Nuclear Information System (INIS)

    Enam, R.N.; Tahir, M.; Ahmed, S.; Qureshi, R.

    2018-01-01

    WSN (Wireless Sensor Network) is an emerging technology that has unlimited potential for numerous application areas including military, crisis management, environmental, transportation, medical, home/ city automations and smart spaces. But energy constrained nature of WSNs necessitates that their architecture and communicating protocols to be designed in an energy aware manner. Sensor data collection through clustering mechanisms has become a common strategy in WSN. This paper presents a survey report on the major perspectives with which energy conservation mechanisms has been proposed in dynamic cluster based WSNs so far. All the solutions discussed in this paper focus on the cluster based protocols only.We have covered a vast scale of existing energy efficient protocols and have categorized them in six categories. In the beginning of this paper the fundamentals of the energy constraint issues of WSNs have been discussed and an overview of the causes of energy consumptions at all layers of WSN has been given. Later in this paper several previously proposed energy efficient protocols of WSNs are presented. (author)

  2. A Survey of Energy Conservation Mechanisms for Dynamic Cluster Based Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Rabia Noor Enam

    2018-04-01

    Full Text Available WSN (Wireless Sensor Network is an emerging technology that has unlimited potential for numerous application areas including military, crisis management, environmental, transportation, medical, home/ city automations and smart spaces. But energy constrained nature of WSNs necessitates that their architecture and communicating protocols to be designed in an energy aware manner. Sensor data collection through clustering mechanisms has become a common strategy in WSN. This paper presents a survey report on the major perspectives with which energy conservation mechanisms has been proposed in dynamic cluster based WSNs so far. All the solutions discussed in this paper focus on the cluster based protocols only.We have covered a vast scale of existing energy efficient protocols and have categorized them in six categories. In the beginning of this paper the fundamentals of the energy constraint issues of WSNs have been discussed and an overview of the causes of energy consumptions at all layers of WSN has been given. Later in this paper several previously proposed energy efficient protocols of WSNs are presented.

  3. Multispecies genetic objectives in spatial conservation planning.

    Science.gov (United States)

    Nielsen, Erica S; Beger, Maria; Henriques, Romina; Selkoe, Kimberly A; von der Heyden, Sophie

    2017-08-01

    Growing threats to biodiversity and global alteration of habitats and species distributions make it increasingly necessary to consider evolutionary patterns in conservation decision making. Yet, there is no clear-cut guidance on how genetic features can be incorporated into conservation-planning processes, despite multiple molecular markers and several genetic metrics for each marker type to choose from. Genetic patterns differ between species, but the potential tradeoffs among genetic objectives for multiple species in conservation planning are currently understudied. We compared spatial conservation prioritizations derived from 2 metrics of genetic diversity (nucleotide and haplotype diversity) and 2 metrics of genetic isolation (private haplotypes and local genetic differentiation) in mitochondrial DNA of 5 marine species. We compared outcomes of conservation plans based only on habitat representation with plans based on genetic data and habitat representation. Fewer priority areas were selected for conservation plans based solely on habitat representation than on plans that included habitat and genetic data. All 4 genetic metrics selected approximately similar conservation-priority areas, which is likely a result of prioritizing genetic patterns across a genetically diverse array of species. Largely, our results suggest that multispecies genetic conservation objectives are vital to creating protected-area networks that appropriately preserve community-level evolutionary patterns. © 2016 Society for Conservation Biology.

  4. A history of conservation politics in Madagascar

    African Journals Online (AJOL)

    1984-04-03

    Apr 3, 1984 ... MADAGASCAR CONSERVATION & DEVELOPMENT ... across multiple geographic and institutional sites. .... lected cases, I provide only general organizational associations for ... began studying ring-tailed lemurs in 1962, followed by Robert ...... Coordination issues in policy implementation networks: an.

  5. Clustering and Flow Conservation Monitoring Tool for Software Defined Networks

    Directory of Open Access Journals (Sweden)

    Jesús Antonio Puente Fernández

    2018-04-01

    Full Text Available Prediction systems present some challenges on two fronts: the relation between video quality and observed session features and on the other hand, dynamics changes on the video quality. Software Defined Networks (SDN is a new concept of network architecture that provides the separation of control plane (controller and data plane (switches in network devices. Due to the existence of the southbound interface, it is possible to deploy monitoring tools to obtain the network status and retrieve a statistics collection. Therefore, achieving the most accurate statistics depends on a strategy of monitoring and information requests of network devices. In this paper, we propose an enhanced algorithm for requesting statistics to measure the traffic flow in SDN networks. Such an algorithm is based on grouping network switches in clusters focusing on their number of ports to apply different monitoring techniques. Such grouping occurs by avoiding monitoring queries in network switches with common characteristics and then, by omitting redundant information. In this way, the present proposal decreases the number of monitoring queries to switches, improving the network traffic and preventing the switching overload. We have tested our optimization in a video streaming simulation using different types of videos. The experiments and comparison with traditional monitoring techniques demonstrate the feasibility of our proposal maintaining similar values decreasing the number of queries to the switches.

  6. Clustering and Flow Conservation Monitoring Tool for Software Defined Networks.

    Science.gov (United States)

    Puente Fernández, Jesús Antonio; García Villalba, Luis Javier; Kim, Tai-Hoon

    2018-04-03

    Prediction systems present some challenges on two fronts: the relation between video quality and observed session features and on the other hand, dynamics changes on the video quality. Software Defined Networks (SDN) is a new concept of network architecture that provides the separation of control plane (controller) and data plane (switches) in network devices. Due to the existence of the southbound interface, it is possible to deploy monitoring tools to obtain the network status and retrieve a statistics collection. Therefore, achieving the most accurate statistics depends on a strategy of monitoring and information requests of network devices. In this paper, we propose an enhanced algorithm for requesting statistics to measure the traffic flow in SDN networks. Such an algorithm is based on grouping network switches in clusters focusing on their number of ports to apply different monitoring techniques. Such grouping occurs by avoiding monitoring queries in network switches with common characteristics and then, by omitting redundant information. In this way, the present proposal decreases the number of monitoring queries to switches, improving the network traffic and preventing the switching overload. We have tested our optimization in a video streaming simulation using different types of videos. The experiments and comparison with traditional monitoring techniques demonstrate the feasibility of our proposal maintaining similar values decreasing the number of queries to the switches.

  7. Caribbean dry forest networking: an opportunity for conservation

    Science.gov (United States)

    K. Banda-Rodriguez; J. Weintritt; R.T. Pennington

    2016-01-01

    Seasonally dry tropical forest is the most threatened tropical forest in the world. Though its overall plant species diversity is lower than in neighboring biomes such as rain forest, species endemism can be high, and its conservation has often been neglected. Caribbean dry forests face diverse threats including tourism, agriculture, and climate change. The Latin...

  8. Climate change adaptation benefits of potential conservation partnerships.

    Science.gov (United States)

    Monahan, William B; Theobald, David M

    2018-01-01

    We evaluate the world terrestrial network of protected areas (PAs) for its partnership potential in responding to climate change. That is, if a PA engaged in collaborative, trans-boundary management of species, by investing in conservation partnerships with neighboring areas, what climate change adaptation benefits might accrue? We consider core tenets of conservation biology related to protecting large areas with high environmental heterogeneity and low climate change velocity and ask how a series of biodiversity adaptation indicators change across spatial scales encompassing potential PA and non-PA partners. Less than 1% of current world terrestrial PAs equal or exceed the size of established and successful conservation partnerships. Partnering at this scale would increase the biodiversity adaptation indicators by factors up to two orders of magnitude, compared to a null model in which each PA is isolated. Most partnership area surrounding PAs is comprised of non-PAs (70%), indicating the importance of looking beyond the current network of PAs when promoting climate change adaptation. Given monumental challenges with PA-based species conservation in the face of climate change, partnerships provide a logical and achievable strategy for helping areas adapt. Our findings identify where strategic partnering efforts in highly vulnerable areas of the world may prove critical in safeguarding biodiversity.

  9. Vegetation response to climate change : implications for Canada's conservation lands

    International Nuclear Information System (INIS)

    Scott, D.; Lemieux, C.

    2003-01-01

    Studies have shown that Canada's national parks are vulnerable to the impacts of climate change. A wide range of biophysical climate change impacts could affect the integrity of conservation lands in each region of Canada. This report examines the potential impact of climate change on landscape alterations and vegetation distribution in Canada's wide network of conservation lands. It also presents several ways to integrate climate change into existing conservation policy and adaptation strategies. Canada's conservation lands include provincial parks, migratory bird sanctuaries, national wildlife areas and wildlife protected areas. This is the first study to examine biome changes by applying an equilibrium Global Vegetation Model (GVM) to Canada's network of national park systems. Some of the policy and planning challenges posed by changes in landscape level vegetation were also addressed. The report indicates that in terms of potential changes to the biome classification of Canada's national forests, more northern biomes are projected to decrease. These northern biomes include the tundra, taiga and boreal conifer forests. 56 refs., 8 tabs., 6 figs

  10. Balancing conservation needs with uses of river ecosystems

    International Nuclear Information System (INIS)

    Sabater, Sergi; Elosegui, Arturo

    2014-01-01

    Rivers are among the most diverse and threatened ecosystems on the earth, but their conservation are a requisite for sustainable development. Conservation must consider both the structure and the functioning of the elements (usually species), as well as of their ecosystem. Therefore, successful river conservation must go beyond protecting species to protecting entire ecosystems and the processes that give each ecosystem its special characteristics. River conservation has to meet the legitimate aspirations of human populations for clean, readily available supply of water, without compromising the water needs of ecosystems and nature. Therefore, it is essential to take a landscape perspective that incorporates processes occurring in the riverine riparian areas as well as on connectivity with the land and across the river network.

  11. Conditions for the adoption of conservation agriculture in Central Morocco: an approach based on Bayesian network modelling

    Directory of Open Access Journals (Sweden)

    Laura Bonzanigo

    2016-03-01

    Full Text Available Research in Central Morocco, proves that conservation agriculture increases yields, reduces labour requirements, and erosion, and improves soil fertility. However, after nearly two decades of demonstration and advocacy, adoption is still limited. This paper investigates the critical constraints and potential opportunities for the adoption of conservation agriculture for different typologies of farms. We measured the possible pathways of adoption via a Bayesian decision network (BDN. BDNs allow the inclusion of stakeholders’ knowledge where data is scant, whilst at the same time they are supported by a robust mathematical background. We first developed a conceptual map of the elements affecting the decision about tillage, which we refined in a workshop with farmers and researchers from the Settat area. We then involved experts in the elicitation of conditional probabilities tables, to quantify the cascade of causal links that determine (or not the adoption. Via BDNs, we could categorise under which specific technical and socio-economic conditions no tillage agriculture is best suited to which farmers. We, by identifying the main constraints and running sensitivity analyses, were able to convey clear messages on how policy- makers may facilitate the conversion. As new evidence is collected, the BDN can be updated to obtain evidence more targeted and fine tuned to the adoption contexts.

  12. Zoos through the Lens of the IUCN Red List: A Global Metapopulation Approach to Support Conservation Breeding Programs

    Science.gov (United States)

    Conde, Dalia A.; Colchero, Fernando; Gusset, Markus; Pearce-Kelly, Paul; Byers, Onnie; Flesness, Nate; Browne, Robert K.; Jones, Owen R.

    2013-01-01

    Given current extinction trends, the number of species requiring conservation breeding programs (CBPs) is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23%) terrestrial vertebrate species in ISIS zoos are threatened. Only two of the 59 taxonomic orders show a higher proportion of threatened species in ISIS zoos than would be expected if species were selected at random. In addition, for most taxa, the management of a zoo metapopulation of more than 250 individuals will require the coordination of a cluster of 11 to 24 ISIS zoos within a radius of 2,000 km. Thus, in the zoo network, the representation of species that may require CBPs is currently low and the spatial distribution of these zoo populations makes management difficult. Although the zoo community may have the will and the logistical potential to contribute to conservation actions, including CBPs, to do so will require greater collaboration between zoos and other institutions, alongside the development of international agreements that facilitate cross-border movement of zoo animals. To maximize the effectiveness of integrated conservation actions that include CBPs, it is fundamental that the non-zoo conservation community acknowledges and integrates the expertise and facilities of zoos where it can be helpful. PMID:24348999

  13. Zoos through the lens of the IUCN Red List: a global metapopulation approach to support conservation breeding programs.

    Science.gov (United States)

    Conde, Dalia A; Colchero, Fernando; Gusset, Markus; Pearce-Kelly, Paul; Byers, Onnie; Flesness, Nate; Browne, Robert K; Jones, Owen R

    2013-01-01

    Given current extinction trends, the number of species requiring conservation breeding programs (CBPs) is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23%) terrestrial vertebrate species in ISIS zoos are threatened. Only two of the 59 taxonomic orders show a higher proportion of threatened species in ISIS zoos than would be expected if species were selected at random. In addition, for most taxa, the management of a zoo metapopulation of more than 250 individuals will require the coordination of a cluster of 11 to 24 ISIS zoos within a radius of 2,000 km. Thus, in the zoo network, the representation of species that may require CBPs is currently low and the spatial distribution of these zoo populations makes management difficult. Although the zoo community may have the will and the logistical potential to contribute to conservation actions, including CBPs, to do so will require greater collaboration between zoos and other institutions, alongside the development of international agreements that facilitate cross-border movement of zoo animals. To maximize the effectiveness of integrated conservation actions that include CBPs, it is fundamental that the non-zoo conservation community acknowledges and integrates the expertise and facilities of zoos where it can be helpful.

  14. Zoos through the lens of the IUCN Red List: a global metapopulation approach to support conservation breeding programs.

    Directory of Open Access Journals (Sweden)

    Dalia A Conde

    Full Text Available Given current extinction trends, the number of species requiring conservation breeding programs (CBPs is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23% terrestrial vertebrate species in ISIS zoos are threatened. Only two of the 59 taxonomic orders show a higher proportion of threatened species in ISIS zoos than would be expected if species were selected at random. In addition, for most taxa, the management of a zoo metapopulation of more than 250 individuals will require the coordination of a cluster of 11 to 24 ISIS zoos within a radius of 2,000 km. Thus, in the zoo network, the representation of species that may require CBPs is currently low and the spatial distribution of these zoo populations makes management difficult. Although the zoo community may have the will and the logistical potential to contribute to conservation actions, including CBPs, to do so will require greater collaboration between zoos and other institutions, alongside the development of international agreements that facilitate cross-border movement of zoo animals. To maximize the effectiveness of integrated conservation actions that include CBPs, it is fundamental that the non-zoo conservation community acknowledges and integrates the expertise and facilities of zoos where it can be helpful.

  15. Why be red listed? Threatened Myriapoda species in Brazil with implications for their conservation.

    Science.gov (United States)

    Karam-Gemael, Manoela; Izzo, Thiago Junqueira; Chagas, Amazonas

    2018-01-01

    The biodiversity crisis we live in, marked by high extinction rates, requires well-planned conservation efforts. To overcome this issue, red lists of threatened species are recognized as the main objective approach for evaluating the conservation status of species and therefore guiding conservation priorities. This work focuses on the Myriapoda (Chilopoda and Diplopoda) species listed in the Brazilian red list of fauna to enable discussion of the practical implications of red lists for conservation. Almost all myriapods assessed are endemic to Brazil (99 %) and 73 % are known from subterranean habitats only. Despite of 33 % being recorded from protected areas (PAs), downgrading, degazettement or downsizing of PAs and intense and unregulated ecotourism represent great threats. The PAs network in Brazil tends to fail in conserving myriapod species. The number of data deficient species (42 %) states the need of investing in ecological and taxonomic studies about the group, in order to fill in important knowledge gaps in species assessments nationally and globally. In this work we show that there is a lack of communication between national and global agencies concerning red lists, which results in a significant loss for science and for conservation. Despite investing in national and state red lists, individual countries must take the final step of submitting its data to IUCN global database, as significant international funding is available for IUCN red listed species conservation. Being one of the most diverse countries in the world, and facing the biggest cuts ever on national science funding, losing these important funding opportunities is a huge loss for Brazilian biodiversity conservation and for science. This study raises awareness on subterranean habitats conservation, due to its high endemism and fragility. Since the first edition of the Brazilian Red List in 1968, centipedes are now included for the first time, and millipedes for the second time. The presence

  16. Downstream-based Scheduling for Energy Conservation in Green EPONs

    KAUST Repository

    Chen, Shen

    2012-05-01

    Maximizing the optical network unit’s (ONU) sleep time is an effective approach for achieving maximum energy conservation in green Ethernet passive optical networks (EPONs). While overlapping downstream and upstream ONU transmissions can maximize the ONU sleep time, it jeopardizes the quality of service (QoS) performance of the network, especially for downstream traffic in case the overlapping is based on the upstream time slot. In this paper, we study the downstream traffic performance in green EPONs under the limited service discipline and the upstream-based overlapped time window. Specifically, we first derive the expected mean packet delay, and then present a closed-form expression of the ONU sleep time, setting identical upstream/downstream transmission cycle times based on a maximum downstream traffic delay re-quirement. With the proposed system model, we present a novel downstream bandwidth allocation scheme for energy conservation in green EPONs. Simulation results verify the proposed model and highlight the advantages of our scheme over conventional approaches.

  17. A novel delay-dependent criterion for delayed neural networks of neutral type

    International Nuclear Information System (INIS)

    Lee, S.M.; Kwon, O.M.; Park, Ju H.

    2010-01-01

    This Letter considers a robust stability analysis method for delayed neural networks of neutral type. By constructing a new Lyapunov functional, a novel delay-dependent criterion for the stability is derived in terms of LMIs (linear matrix inequalities). A less conservative stability criterion is derived by using nonlinear properties of the activation function of the neural networks. Two numerical examples are illustrated to show the effectiveness of the proposed method.

  18. NATURE CONSERVATION MOVEMENT IN THE WORLD: ITS HISTORICAL DEVELOPMENT AND PRESENT SITUATION

    Directory of Open Access Journals (Sweden)

    Oğuz Kurdoğlu

    2007-04-01

    Full Text Available Although nature conservation is a well recognized topic at present, it is not a new phenomenon. Throughout history, there are numerous examples of efforts made by governments, rulers, or individual land owners to protect certain land areas that possessed unique natural values. While many of these areas were actually isolated as game preserves for hunting, they were also designed to conserve wildlife. The establishment of Yellowstone National Park in 1972 marks the modern concept of a national park as it was designed on a very large protected natural area. Presently, one of the most efficient ways for nature protection is “area conservation approach” that many organizations have been developing various systems and categories about. Unfortunately, in spite of such improvements and the extension of the protected area network, many of these areas are not properly protected and/or managed in some countries. This study summarizes the historical evolution of nature conservation systems and strategies in the world with the related international legislative aspects as well. As it stated in this paper, USA and Europa have a well known history on nature conservation and show great concern in respect to participating to the international convention and arrangements.

  19. Mutational robustness of gene regulatory networks.

    Directory of Open Access Journals (Sweden)

    Aalt D J van Dijk

    Full Text Available Mutational robustness of gene regulatory networks refers to their ability to generate constant biological output upon mutations that change network structure. Such networks contain regulatory interactions (transcription factor-target gene interactions but often also protein-protein interactions between transcription factors. Using computational modeling, we study factors that influence robustness and we infer several network properties governing it. These include the type of mutation, i.e. whether a regulatory interaction or a protein-protein interaction is mutated, and in the case of mutation of a regulatory interaction, the sign of the interaction (activating vs. repressive. In addition, we analyze the effect of combinations of mutations and we compare networks containing monomeric with those containing dimeric transcription factors. Our results are consistent with available data on biological networks, for example based on evolutionary conservation of network features. As a novel and remarkable property, we predict that networks are more robust against mutations in monomer than in dimer transcription factors, a prediction for which analysis of conservation of DNA binding residues in monomeric vs. dimeric transcription factors provides indirect evidence.

  20. Reconciling Mining with the Conservation of Cave Biodiversity: A Quantitative Baseline to Help Establish Conservation Priorities.

    Science.gov (United States)

    Jaffé, Rodolfo; Prous, Xavier; Zampaulo, Robson; Giannini, Tereza C; Imperatriz-Fonseca, Vera L; Maurity, Clóvis; Oliveira, Guilherme; Brandi, Iuri V; Siqueira, José O

    2016-01-01

    Caves pose significant challenges for mining projects, since they harbor many endemic and threatened species, and must therefore be protected. Recent discussions between academia, environmental protection agencies, and industry partners, have highlighted problems with the current Brazilian legislation for the protection of caves. While the licensing process is long, complex and cumbersome, the criteria used to assign caves into conservation relevance categories are often subjective, with relevance being mainly determined by the presence of obligate cave dwellers (troglobites) and their presumed rarity. However, the rarity of these troglobitic species is questionable, as most remain unidentified to the species level and their habitats and distribution ranges are poorly known. Using data from 844 iron caves retrieved from different speleology reports for the Carajás region (South-Eastern Amazon, Brazil), one of the world's largest deposits of high-grade iron ore, we assess the influence of different cave characteristics on four biodiversity proxies (species richness, presence of troglobites, presence of rare troglobites, and presence of resident bat populations). We then examine how the current relevance classification scheme ranks caves with different biodiversity indicators. Large caves were found to be important reservoirs of biodiversity, so they should be prioritized in conservation programs. Our results also reveal spatial autocorrelation in all the biodiversity proxies assessed, indicating that iron caves should be treated as components of a cave network immersed in the karst landscape. Finally, we show that by prioritizing the conservation of rare troglobites, the current relevance classification scheme is undermining overall cave biodiversity and leaving ecologically important caves unprotected. We argue that conservation efforts should target subterranean habitats as a whole and propose an alternative relevance ranking scheme, which could help simplify the

  1. Conservation Action Planning: Lessons learned from the St. Marys River watershed biodiversity conservation planning process

    Science.gov (United States)

    Patterson, Tamatha A.; Grundel, Ralph

    2014-01-01

    Conservation Action Planning (CAP) is an adaptive management planning process refined by The Nature Conservancy (TNC) and embraced worldwide as the Open Standards for the Practice of Conservation. The CAP process facilitates open, multi-institutional collaboration on a common conservation agenda through organized actions and quantified results. While specifically designed for conservation efforts, the framework is adaptable and flexible to multiple scales and can be used for any collaborative planning effort. The CAP framework addresses inception; design and development of goals, measures, and strategies; and plan implementation and evaluation. The specific components of the CAP include defining the project scope and conservation targets; assessing the ecological viability; ascertaining threats and surrounding situation; identifying opportunities and designing strategies for action; and implementing actions and monitoring results. In 2007, TNC and a multidisciplinary graduate student team from the University of Michigan's School of Natural Resources and Environment initiated a CAP for the St. Marys River, the connecting channel between Lake Superior and Lake Huron, and its local watershed. The students not only gained experience in conservation planning, but also learned lessons that notably benefited the CAP process and were valuable for any successful collaborative effort—a dedicated core team improved product quality, accelerated the timeline, and provided necessary support for ongoing efforts; an academic approach in preparation for engagement in the planning process brought applicable scientific research to the forefront, enhanced workshop facilitation, and improved stakeholder participation; and early and continuous interactions with regional stakeholders improved cooperation and built a supportive network for collaboration.

  2. Observability and Controllability of Networks: Symmetry in Representations of Brains and Controllers for Epidemics

    Science.gov (United States)

    Schiff, Steven

    Observability and controllability are essential concepts to the design of predictive observer models and feedback controllers of networked systems. We present a numerical and group representational framework, to quantify the observability and controllability of nonlinear networks with explicit symmetries that shows the connection between symmetries and nonlinear measures of observability and controllability. In addition to the topology of brain networks, we have advanced our ability to represent network nodes within the brain using conservation principles and more accurate biophysics that unifies the dynamics of spikes, seizures, and spreading depression. Lastly, we show how symmetries in controller design can be applied to infectious disease epidemics. NIH Grants 1R01EB014641, 1DP1HD086071.

  3. Mean square stabilization and mean square exponential stabilization of stochastic BAM neural networks with Markovian jumping parameters

    International Nuclear Information System (INIS)

    Ye, Zhiyong; Zhang, He; Zhang, Hongyu; Zhang, Hua; Lu, Guichen

    2015-01-01

    Highlights: •This paper introduces a non-conservative Lyapunov functional. •The achieved results impose non-conservative and can be widely used. •The conditions are easily checked by the Matlab LMI Tool Box. The desired state feedback controller can be well represented by the conditions. -- Abstract: This paper addresses the mean square exponential stabilization problem of stochastic bidirectional associative memory (BAM) neural networks with Markovian jumping parameters and time-varying delays. By establishing a proper Lyapunov–Krasovskii functional and combining with LMIs technique, several sufficient conditions are derived for ensuring exponential stabilization in the mean square sense of such stochastic BAM neural networks. In addition, the achieved results are not difficult to verify for determining the mean square exponential stabilization of delayed BAM neural networks with Markovian jumping parameters and impose less restrictive and less conservative than the ones in previous papers. Finally, numerical results are given to show the effectiveness and applicability of the achieved results

  4. A UV-Induced Genetic Network Links the RSC Complex to Nucleotide Excision Repair and Shows Dose-Dependent Rewiring

    Directory of Open Access Journals (Sweden)

    Rohith Srivas

    2013-12-01

    Full Text Available Efficient repair of UV-induced DNA damage requires the precise coordination of nucleotide excision repair (NER with numerous other biological processes. To map this crosstalk, we generated a differential genetic interaction map centered on quantitative growth measurements of >45,000 double mutants before and after different doses of UV radiation. Integration of genetic data with physical interaction networks identified a global map of 89 UV-induced functional interactions among 62 protein complexes, including a number of links between the RSC complex and several NER factors. We show that RSC is recruited to both silenced and transcribed loci following UV damage where it facilitates efficient repair by promoting nucleosome remodeling. Finally, a comparison of the response to high versus low levels of UV shows that the degree of genetic rewiring correlates with dose of UV and reveals a network of dose-specific interactions. This study makes available a large resource of UV-induced interactions, and it illustrates a methodology for identifying dose-dependent interactions based on quantitative shifts in genetic networks.

  5. Effective Data Acquisition Protocol for Multi-Hop Heterogeneous Wireless Sensor Networks Using Compressive Sensing

    Directory of Open Access Journals (Sweden)

    Ahmed M. Khedr

    2015-10-01

    Full Text Available In designing wireless sensor networks (WSNs, it is important to reduce energy dissipation and prolong network lifetime. Clustering of nodes is one of the most effective approaches for conserving energy in WSNs. Cluster formation protocols generally consider the heterogeneity of sensor nodes in terms of energy difference of nodes but ignore the different transmission ranges of them. In this paper, we propose an effective data acquisition clustered protocol using compressive sensing (EDACP-CS for heterogeneous WSNs that aims to conserve the energy of sensor nodes in the presence of energy and transmission range heterogeneity. In EDACP-CS, cluster heads are selected based on the distance from the base station and sensor residual energy. Simulation results show that our protocol offers a much better performance than the existing protocols in terms of energy consumption, stability, network lifetime, and throughput.

  6. Functional Conservation of the Glide/Gcm Regulatory Network Controlling Glia, Hemocyte, and Tendon Cell Differentiation in Drosophila

    Science.gov (United States)

    Cattenoz, Pierre B.; Popkova, Anna; Southall, Tony D.; Aiello, Giuseppe; Brand, Andrea H.; Giangrande, Angela

    2016-01-01

    High-throughput screens allow us to understand how transcription factors trigger developmental processes, including cell specification. A major challenge is identification of their binding sites because feedback loops and homeostatic interactions may mask the direct impact of those factors in transcriptome analyses. Moreover, this approach dissects the downstream signaling cascades and facilitates identification of conserved transcriptional programs. Here we show the results and the validation of a DNA adenine methyltransferase identification (DamID) genome-wide screen that identifies the direct targets of Glide/Gcm, a potent transcription factor that controls glia, hemocyte, and tendon cell differentiation in Drosophila. The screen identifies many genes that had not been previously associated with Glide/Gcm and highlights three major signaling pathways interacting with Glide/Gcm: Notch, Hedgehog, and JAK/STAT, which all involve feedback loops. Furthermore, the screen identifies effector molecules that are necessary for cell-cell interactions during late developmental processes and/or in ontogeny. Typically, immunoglobulin (Ig) domain–containing proteins control cell adhesion and axonal navigation. This shows that early and transiently expressed fate determinants not only control other transcription factors that, in turn, implement a specific developmental program but also directly affect late developmental events and cell function. Finally, while the mammalian genome contains two orthologous Gcm genes, their function has been demonstrated in vertebrate-specific tissues, placenta, and parathyroid glands, begging questions on the evolutionary conservation of the Gcm cascade in higher organisms. Here we provide the first evidence for the conservation of Gcm direct targets in humans. In sum, this work uncovers novel aspects of cell specification and sets the basis for further understanding of the role of conserved Gcm gene regulatory cascades. PMID:26567182

  7. A Network Integration Approach to Predict Conserved Regulators Related to Pathogenicity of Influenza and SARS-CoV Respiratory Viruses

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Hugh D.; Eisfeld, Amie J.; Sims, Amy; McDermott, Jason E.; Matzke, Melissa M.; Webb-Robertson, Bobbie-Jo M.; Tilton, Susan C.; Tchitchek, Nicholas; Josset, Laurence; Li, Chengjun; Ellis, Amy L.; Chang, Jean H.; Heegel, Robert A.; Luna, Maria L.; Schepmoes, Athena A.; Shukla, Anil K.; Metz, Thomas O.; Neumann, Gabriele; Benecke, Arndt; Smith, Richard D.; Baric, Ralph; Kawaoka, Yoshihiro; Katze, Michael G.; Waters, Katrina M.

    2013-07-25

    Respiratory infections stemming from influenza viruses and the Severe Acute Respiratory Syndrome corona virus (SARS-CoV) represent a serious public health threat as emerging pandemics. Despite efforts to identify the critical interactions of these viruses with host machinery, the key regulatory events that lead to disease pathology remain poorly targeted with therapeutics. Here we implement an integrated network interrogation approach, in which proteome and transcriptome datasets from infection of both viruses in human lung epithelial cells are utilized to predict regulatory genes involved in the host response. We take advantage of a novel “crowd-based” approach to identify and combine ranking metrics that isolate genes/proteins likely related to the pathogenicity of SARS-CoV and influenza virus. Subsequently, a multivariate regression model is used to compare predicted lung epithelial regulatory influences with data derived from other respiratory virus infection models. We predicted a small set of regulatory factors with conserved behavior for consideration as important components of viral pathogenesis that might also serve as therapeutic targets for intervention. Our results demonstrate the utility of integrating diverse ‘omic datasets to predict and prioritize regulatory features conserved across multiple pathogen infection models.

  8. Conservation of the Critically Endangered Eastern Australian Population of the Grey Nurse Shark ( Carcharias taurus) Through Cross-Jurisdictional Management of a Network of Marine-Protected Areas

    Science.gov (United States)

    Lynch, Tim P.; Harcourt, Robert; Edgar, Graham; Barrett, Neville

    2013-12-01

    Between 2001 and 2009, 26 marine-protected areas (MPA) were established on the east Australian seaboard, at least in part, to manage human interactions with a critically endangered population of grey nurse shark, Carcharias taurus. This network is spread across six MPA systems and includes all 19 sites outlined in the National Recovery Plan for C. taurus, though five sites remain open to some forms of fishing. The reserve network has complex cross-jurisdictional management, as the sharks occur in waters controlled by the Australian states of New South Wales (NSW) and Queensland, as well as by the Commonwealth (Federal) government. Jurisdiction is further complicated by fisheries and conservation departments both engaging in management activities within each state. This has resulted in protected area types that include IUCN category II equivalent zones in NSW, Queensland, and Commonwealth marine parks that either overlay or complement another large scaled network of protected sites called critical habitats. Across the network, seven and eight rule permutations for diving and fishing, respectively, are applied to this population of sharks. Besides sites identified by the recovery plan, additional sites have been protected as part of the general development of MPA networks. A case study at one of these sites, which historically was known to be occupied by C. taurus but had been abandoned, appears to shows re-establishment of an aggregation of juvenile and sub-adult sharks. Concurrent with the re-establishment of the aggregation, a local dive operator increased seasonal dive visitation rates at the site fourfold. As a precautionary measure, protection of abandoned sites, which includes nursery and gestating female habitats are options that may assist recovery of the east coast population of C. taurus.

  9. MOUNTAIN NATURAL BIODIVERSITY CONSERVATION IN RUSSIA

    Directory of Open Access Journals (Sweden)

    Arkady Tishkov

    2012-01-01

    Full Text Available High biodiversity and degree of endemism of mountain biota strengthen the mountain regions’ status for the territorial nature conservation. Analysis of the protected areas’ representativeness in various mountain regions of Russia shows some discrepancy between their quantity, square and regional biodiversity originality. The biggest divergences are marked for the Northern Caucasus. The main problems: small area of the protected territories and also cluster character of their spatial distribution, mostly in the high mountains are not supposed to conform with the highest values of the regional flora’s and fauna’s uniqueness, to compensate representativeness of the protected biota and, in anyway, to correspond with the purpose of nature protection frame—the protected territories ecologic network’s forming. The situation in the Urals, Siberia and the Far East seems to be better. The large areas of the protected territories are in general agreement with the high originality of the nature ecosystems. Nevertheless each concrete case needs analysis of the regional biota’s and ecosystems’ biodiversity distribution within the protected areas, including character and (or unique elements of the regional biodiversity to be held. The development of the effectual territorial conservation of mountain regions needs differential approach. The creation of the large representative parcels of nature landscapes in the key-areas has the considerable meaning in the low-developed regions, difficult to access. And well-developed regions have the necessity of nature protected territories’ network development and the planning of the ecological frame’s forming. The territorial biodiversity conservation, including the system of federal, regional and local levels with protective conservation of the rare species has to be combined with ecosystem’s restoration, especially in the zones disturbed by erosion, recreation and military actions. Also it is

  10. How Should Beta-Diversity Inform Biodiversity Conservation?

    Science.gov (United States)

    Socolar, Jacob B; Gilroy, James J; Kunin, William E; Edwards, David P

    2016-01-01

    To design robust protected area networks, accurately measure species losses, or understand the processes that maintain species diversity, conservation science must consider the organization of biodiversity in space. Central is beta-diversity--the component of regional diversity that accumulates from compositional differences between local species assemblages. We review how beta-diversity is impacted by human activities, including farming, selective logging, urbanization, species invasions, overhunting, and climate change. Beta-diversity increases, decreases, or remains unchanged by these impacts, depending on the balance of processes that cause species composition to become more different (biotic heterogenization) or more similar (biotic homogenization) between sites. While maintaining high beta-diversity is not always a desirable conservation outcome, understanding beta-diversity is essential for protecting regional diversity and can directly assist conservation planning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Delay-Dependent Exponential Stability for Discrete-Time BAM Neural Networks with Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Yonggang Chen

    2008-01-01

    Full Text Available This paper considers the delay-dependent exponential stability for discrete-time BAM neural networks with time-varying delays. By constructing the new Lyapunov functional, the improved delay-dependent exponential stability criterion is derived in terms of linear matrix inequality (LMI. Moreover, in order to reduce the conservativeness, some slack matrices are introduced in this paper. Two numerical examples are presented to show the effectiveness and less conservativeness of the proposed method.

  12. ZERO: Probabilistic Routing for Deploy and Forget Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jose Carlos Pacho

    2010-09-01

    Full Text Available As Wireless Sensor Networks are being adopted by industry and agriculture for large-scale and unattended deployments, the need for reliable and energy-conservative protocols become critical. Physical and Link layer efforts for energy conservation are not mostly considered by routing protocols that put their efforts on maintaining reliability and throughput. Gradient-based routing protocols route data through most reliable links aiming to ensure 99% packet delivery. However, they suffer from the so-called ”hot spot” problem. Most reliable routes waste their energy fast, thus partitioning the network and reducing the area monitored. To cope with this ”hot spot” problem we propose ZERO a combined approach at Network and Link layers to increase network lifespan while conserving reliability levels by means of probabilistic load balancing techniques.

  13. Opuntia in Mexico: identifying priority areas for conserving biodiversity in a multi-use landscape.

    Directory of Open Access Journals (Sweden)

    Patricia Illoldi-Rangel

    Full Text Available BACKGROUND: México is one of the world's centers of species diversity (richness for Opuntia cacti. Yet, in spite of their economic and ecological importance, Opuntia species remain poorly studied and protected in México. Many of the species are sparsely but widely distributed across the landscape and are subject to a variety of human uses, so devising implementable conservation plans for them presents formidable difficulties. Multi-criteria analysis can be used to design a spatially coherent conservation area network while permitting sustainable human usage. METHODS AND FINDINGS: Species distribution models were created for 60 Opuntia species using MaxEnt. Targets of representation within conservation area networks were assigned at 100% for the geographically rarest species and 10% for the most common ones. Three different conservation plans were developed to represent the species within these networks using total area, shape, and connectivity as relevant criteria. Multi-criteria analysis and a metaheuristic adaptive tabu search algorithm were used to search for optimal solutions. The plans were built on the existing protected areas of México and prioritized additional areas for management for the persistence of Opuntia species. All plans required around one-third of México's total area to be prioritized for attention for Opuntia conservation, underscoring the implausibility of Opuntia conservation through traditional land reservation. Tabu search turned out to be both computationally tractable and easily implementable for search problems of this kind. CONCLUSIONS: Opuntia conservation in México require the management of large areas of land for multiple uses. The multi-criteria analyses identified priority areas and organized them in large contiguous blocks that can be effectively managed. A high level of connectivity was established among the prioritized areas resulting in the enhancement of possible modes of plant dispersal as well as

  14. Genes with stable DNA methylation levels show higher evolutionary conservation than genes with fluctuant DNA methylation levels.

    Science.gov (United States)

    Zhang, Ruijie; Lv, Wenhua; Luan, Meiwei; Zheng, Jiajia; Shi, Miao; Zhu, Hongjie; Li, Jin; Lv, Hongchao; Zhang, Mingming; Shang, Zhenwei; Duan, Lian; Jiang, Yongshuai

    2015-11-24

    Different human genes often exhibit different degrees of stability in their DNA methylation levels between tissues, samples or cell types. This may be related to the evolution of human genome. Thus, we compared the evolutionary conservation between two types of genes: genes with stable DNA methylation levels (SM genes) and genes with fluctuant DNA methylation levels (FM genes). For long-term evolutionary characteristics between species, we compared the percentage of the orthologous genes, evolutionary rate dn/ds and protein sequence identity. We found that the SM genes had greater percentages of the orthologous genes, lower dn/ds, and higher protein sequence identities in all the 21 species. These results indicated that the SM genes were more evolutionarily conserved than the FM genes. For short-term evolutionary characteristics among human populations, we compared the single nucleotide polymorphism (SNP) density, and the linkage disequilibrium (LD) degree in HapMap populations and 1000 genomes project populations. We observed that the SM genes had lower SNP densities, and higher degrees of LD in all the 11 HapMap populations and 13 1000 genomes project populations. These results mean that the SM genes had more stable chromosome genetic structures, and were more conserved than the FM genes.

  15. Vegetation response to climate change : implications for Canada's conservation lands

    Energy Technology Data Exchange (ETDEWEB)

    Scott, D. [Environment Canada, Ottawa, ON (Canada). Adaptation and Impact Research Group; Lemieux, C. [Waterloo Univ., ON (Canada). Dept. of Geography

    2003-05-01

    Studies have shown that Canada's national parks are vulnerable to the impacts of climate change. A wide range of biophysical climate change impacts could affect the integrity of conservation lands in each region of Canada. This report examines the potential impact of climate change on landscape alterations and vegetation distribution in Canada's wide network of conservation lands. It also presents several ways to integrate climate change into existing conservation policy and adaptation strategies. Canada's conservation lands include provincial parks, migratory bird sanctuaries, national wildlife areas and wildlife protected areas. This is the first study to examine biome changes by applying an equilibrium Global Vegetation Model (GVM) to Canada's network of national park systems. Some of the policy and planning challenges posed by changes in landscape level vegetation were also addressed. The report indicates that in terms of potential changes to the biome classification of Canada's national forests, more northern biomes are projected to decrease. These northern biomes include the tundra, taiga and boreal conifer forests. 56 refs., 8 tabs., 6 figs.

  16. [Strategies for Conservation of Endangered Amphibian and Reptile Species].

    Science.gov (United States)

    Anan'eva, N B; Uteshev, V K; Orlova, N L; Gakhova, E N

    2015-01-01

    Strategies for conservation of endangered amphibian and reptile species are discussed. One-fifth of all vertebrates belongs to the category of "endangered species," and amphibians are first on the list (41%). Every fifth reptile species is in danger of extinction, and insufficient information is characteristic of every other fifth. As has been demonstrated, efficient development of a network of nature conservation areas, cryopreservation, and methods for laboratory breeding and reintroduction play.the key roles in adequate strategies for preservation of amphibians and reptiles.

  17. The Evolution of Gene Regulatory Networks that Define Arthropod Body Plans.

    Science.gov (United States)

    Auman, Tzach; Chipman, Ariel D

    2017-09-01

    Our understanding of the genetics of arthropod body plan development originally stems from work on Drosophila melanogaster from the late 1970s and onward. In Drosophila, there is a relatively detailed model for the network of gene interactions that proceeds in a sequential-hierarchical fashion to define the main features of the body plan. Over the years, we have a growing understanding of the networks involved in defining the body plan in an increasing number of arthropod species. It is now becoming possible to tease out the conserved aspects of these networks and to try to reconstruct their evolution. In this contribution, we focus on several key nodes of these networks, starting from early patterning in which the main axes are determined and the broad morphological domains of the embryo are defined, and on to later stage wherein the growth zone network is active in sequential addition of posterior segments. The pattern of conservation of networks is very patchy, with some key aspects being highly conserved in all arthropods and others being very labile. Many aspects of early axis patterning are highly conserved, as are some aspects of sequential segment generation. In contrast, regional patterning varies among different taxa, and some networks, such as the terminal patterning network, are only found in a limited range of taxa. The growth zone segmentation network is ancient and is probably plesiomorphic to all arthropods. In some insects, it has undergone significant modification to give rise to a more hardwired network that generates individual segments separately. In other insects and in most arthropods, the sequential segmentation network has undergone a significant amount of systems drift, wherein many of the genes have changed. However, it maintains a conserved underlying logic and function. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please

  18. Conservation and reclamation at Alberta's mineable oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Purdy, B.; Richens, T. [Alberta Environment, Edmonton, AB (Canada)

    2010-07-01

    The regulatory foundation for oil sands in this region is established by the Energy Resources Conservation Board, Environmental Protection and Enhancement Act (EPEA), as well as the Water Act. This presentation discussed the regulatory foundation for conservation and reclamation in the mineable oil sands region. EPEA requirements and conservation objectives were identified. EPEA conservation and reclamation requirements stipulate that an operator must conserve and reclaim and obtain a reclamation certificate. EPEA approvals that were presented compared prescriptive standards versus meeting outcomes at certification. Operational and management challenges as well as the role of research networks and multi-stakeholder organizations were also addressed. Challenge facing the industry include progressive reclamation; tailings management and process-affected water; reclamation certification; integrated landscapes; soil handling and revegetation and monitoring and research. The presentation demonstrated that reclamation begins with mine planning and ends with certification. figs.

  19. ADM pseudotensors, conserved quantities and covariant conservation laws in general relativity

    International Nuclear Information System (INIS)

    Fatibene, L.; Ferraris, M.; Francaviglia, M.; Lusanna, L.

    2012-01-01

    The ADM formalism is reviewed and techniques for decomposing generic components of metric, connection and curvature are obtained. These techniques will turn out to be enough to decompose not only Einstein equations but also covariant conservation laws. Then a number of independent sets of hypotheses that are sufficient (though not necessary) to obtain standard ADM quantities (and Hamiltonian) from covariant conservation laws are considered. This determines explicitly the range in which standard techniques are equivalent to covariant conserved quantities. The Schwarzschild metric in different coordinates is then considered, showing how the standard ADM quantities fail dramatically in non-Cartesian coordinates or even worse when asymptotically flatness is not manifest; while, in view of their covariance, covariant conservation laws give the correct result in all cases. - Highlights: ► In the paper ADM conserved quantities for GR are obtained from augmented conservation laws. ► Boundary conditions for this to be possible are considered and compared with the literature. ► Some different forms of Schwarzschild solutions are considered as simple examples of different boundary conditions.

  20. Recurrent and multiple bladder tumors show conserved expression profiles

    International Nuclear Information System (INIS)

    Lindgren, David; Fioretos, Thoas; Månsson, Wiking; Höglund, Mattias; Gudjonsson, Sigurdur; Jee, Kowan Ja; Liedberg, Fredrik; Aits, Sonja; Andersson, Anna; Chebil, Gunilla; Borg, Åke; Knuutila, Sakari

    2008-01-01

    Urothelial carcinomas originate from the epithelial cells of the inner lining of the bladder and may appear as single or as multiple synchronous tumors. Patients with urothelial carcinomas frequently show recurrences after treatment making follow-up necessary. The leading hypothesis explaining the origin of meta- and synchronous tumors assumes a monoclonal origin. However, the genetic relationship among consecutive tumors has been shown to be complex in as much as the genetic evolution does not adhere to the chronological appearance of the metachronous tumors. Consequently, genetically less evolved tumors may appear chronologically later than genetically related but more evolved tumors. Forty-nine meta- or synchronous urothelial tumors from 22 patients were analyzed using expression profiling, conventional CGH, LOH, and mutation analyses. We show by CGH that partial chromosomal losses in the initial tumors may not be present in the recurring tumors, by LOH that different haplotypes may be lost and that detected regions of LOH may be smaller in recurring tumors, and that mutations present in the initial tumor may not be present in the recurring ones. In contrast we show that despite apparent genomic differences, the recurrent and multiple bladder tumors from the same patients display remarkably similar expression profiles. Our findings show that even though the vast majority of the analyzed meta- and synchronous tumors from the same patients are not likely to have originated directly from the preceding tumor they still show remarkably similar expressions profiles. The presented data suggests that an expression profile is established early in tumor development and that this profile is stable and maintained in recurring tumors

  1. Ex situ conservation of plant diversity in the world's botanic gardens.

    Science.gov (United States)

    Mounce, Ross; Smith, Paul; Brockington, Samuel

    2017-10-01

    Botanic gardens conserve plant diversity ex situ and can prevent extinction through integrated conservation action. Here we quantify how that diversity is conserved in ex situ collections across the world's botanic gardens. We reveal that botanic gardens manage at least 105,634 species, equating to 30% of all plant species diversity, and conserve over 41% of known threatened species. However, we also reveal that botanic gardens are disproportionately temperate, with 93% of species held in the Northern Hemisphere. Consequently, an estimated 76% of species absent from living collections are tropical in origin. Furthermore, phylogenetic bias ensures that over 50% of vascular genera, but barely 5% of non-vascular genera, are conserved ex situ. While botanic gardens are discernibly responding to the threat of species extinction, just 10% of network capacity is devoted to threatened species. We conclude that botanic gardens play a fundamental role in plant conservation, but identify actions to enhance future conservation of biodiversity.

  2. Social participation and oak forest conservation: Paipa and Duitama study case

    International Nuclear Information System (INIS)

    Escobar Torres, Vivian Constanza; Palacio Tamayo, Dolly Cristina

    2010-01-01

    Social dynamics within social participation is a crucial issue for the accomplishment of forest conservation. In order to contribute to this field, a study of 31 institutional and community organized actors' cooperative practices, within forest conservation processes in Paipa and Duitama, located at the oak forests conservation corridor Guantiva, La Rusia, Iguaque in Colombia, was made, applying Social Network Analysis (SNA). Particularly, this article inquiry is about models of participation of these actors within the period of 2004-2008, looking at their projects and actions as management practices of forest conservation. The research questions were how social participation is included and understood in the conservation of these oak forests, observing cooperative practices amongst this set of actors, at local level. The results are related with the structural patterns of co-participation established amongst these actors within each other's projects and actions and the impact of those in the aim of forest conservation at local level, regarding power relations and its impact on forest conservation.

  3. Conserved molecular interactions in centriole-to-centrosome conversion.

    Science.gov (United States)

    Fu, Jingyan; Lipinszki, Zoltan; Rangone, Hélène; Min, Mingwei; Mykura, Charlotte; Chao-Chu, Jennifer; Schneider, Sandra; Dzhindzhev, Nikola S; Gottardo, Marco; Riparbelli, Maria Giovanna; Callaini, Giuliano; Glover, David M

    2016-01-01

    Centrioles are required to assemble centrosomes for cell division and cilia for motility and signalling. New centrioles assemble perpendicularly to pre-existing ones in G1-S and elongate throughout S and G2. Fully elongated daughter centrioles are converted into centrosomes during mitosis to be able to duplicate and organize pericentriolar material in the next cell cycle. Here we show that centriole-to-centrosome conversion requires sequential loading of Cep135, Ana1 (Cep295) and Asterless (Cep152) onto daughter centrioles during mitotic progression in both Drosophila melanogaster and human. This generates a molecular network spanning from the inner- to outermost parts of the centriole. Ana1 forms a molecular strut within the network, and its essential role can be substituted by an engineered fragment providing an alternative linkage between Asterless and Cep135. This conserved architectural framework is essential for loading Asterless or Cep152, the partner of the master regulator of centriole duplication, Plk4. Our study thus uncovers the molecular basis for centriole-to-centrosome conversion that renders daughter centrioles competent for motherhood.

  4. Inferring the conservative causal core of gene regulatory networks

    Directory of Open Access Journals (Sweden)

    Emmert-Streib Frank

    2010-09-01

    Full Text Available Abstract Background Inferring gene regulatory networks from large-scale expression data is an important problem that received much attention in recent years. These networks have the potential to gain insights into causal molecular interactions of biological processes. Hence, from a methodological point of view, reliable estimation methods based on observational data are needed to approach this problem practically. Results In this paper, we introduce a novel gene regulatory network inference (GRNI algorithm, called C3NET. We compare C3NET with four well known methods, ARACNE, CLR, MRNET and RN, conducting in-depth numerical ensemble simulations and demonstrate also for biological expression data from E. coli that C3NET performs consistently better than the best known GRNI methods in the literature. In addition, it has also a low computational complexity. Since C3NET is based on estimates of mutual information values in conjunction with a maximization step, our numerical investigations demonstrate that our inference algorithm exploits causal structural information in the data efficiently. Conclusions For systems biology to succeed in the long run, it is of crucial importance to establish methods that extract large-scale gene networks from high-throughput data that reflect the underlying causal interactions among genes or gene products. Our method can contribute to this endeavor by demonstrating that an inference algorithm with a neat design permits not only a more intuitive and possibly biological interpretation of its working mechanism but can also result in superior results.

  5. Inferring the conservative causal core of gene regulatory networks.

    Science.gov (United States)

    Altay, Gökmen; Emmert-Streib, Frank

    2010-09-28

    Inferring gene regulatory networks from large-scale expression data is an important problem that received much attention in recent years. These networks have the potential to gain insights into causal molecular interactions of biological processes. Hence, from a methodological point of view, reliable estimation methods based on observational data are needed to approach this problem practically. In this paper, we introduce a novel gene regulatory network inference (GRNI) algorithm, called C3NET. We compare C3NET with four well known methods, ARACNE, CLR, MRNET and RN, conducting in-depth numerical ensemble simulations and demonstrate also for biological expression data from E. coli that C3NET performs consistently better than the best known GRNI methods in the literature. In addition, it has also a low computational complexity. Since C3NET is based on estimates of mutual information values in conjunction with a maximization step, our numerical investigations demonstrate that our inference algorithm exploits causal structural information in the data efficiently. For systems biology to succeed in the long run, it is of crucial importance to establish methods that extract large-scale gene networks from high-throughput data that reflect the underlying causal interactions among genes or gene products. Our method can contribute to this endeavor by demonstrating that an inference algorithm with a neat design permits not only a more intuitive and possibly biological interpretation of its working mechanism but can also result in superior results.

  6. Animal Social Network Theory Can Help Wildlife Conservation

    NARCIS (Netherlands)

    Snijders, Lysanne; Blumstein, Daniel T.; Stanley, Christina R.; Franks, Daniel W.

    2017-01-01

    Many animals preferentially associate with certain other individuals. This social structuring can influence how populations respond to changes to their environment, thus making network analysis a promising technique for understanding, predicting, and potentially manipulating population dynamics.

  7. Coevolution within a transcriptional network by compensatory trans and cis mutations

    KAUST Repository

    Kuo, D.

    2010-10-26

    Transcriptional networks have been shown to evolve very rapidly, prompting questions as to how such changes arise and are tolerated. Recent comparisons of transcriptional networks across species have implicated variations in the cis-acting DNA sequences near genes as the main cause of divergence. What is less clear is how these changes interact with trans-acting changes occurring elsewhere in the genetic circuit. Here, we report the discovery of a system of compensatory trans and cis mutations in the yeast AP-1 transcriptional network that allows for conserved transcriptional regulation despite continued genetic change. We pinpoint a single species, the fungal pathogen Candida glabrata, in which a trans mutation has occurred very recently in a single AP-1 family member, distinguishing it from its Saccharomyces ortholog. Comparison of chromatin immunoprecipitation profiles between Candida and Saccharomyces shows that, despite their different DNA-binding domains, the AP-1 orthologs regulate a conserved block of genes. This conservation is enabled by concomitant changes in the cis-regulatory motifs upstream of each gene. Thus, both trans and cis mutations have perturbed the yeast AP-1 regulatory system in such a way as to compensate for one another. This demonstrates an example of “coevolution” between a DNA-binding transcription factor and its cis-regulatory site, reminiscent of the coevolution of protein binding partners.

  8. Conservation science in developing countries: an inside perspective on the struggles in sea turtle research and conservation in Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Buitrago, Joaquin [Estacion de Investigaciones Marinas de Margarita, Fundacion La Salle de Ciencias Naturales, Apartado 144, Porlamar, Isla Margarita (Venezuela)], E-mail: jbuitrago@edimar.org; Guada, Hedelvy J. [Centro de Investigacion y Conservacion de Tortugas Marinas CICTMAR, Red de Conservacion de Tortugas Marinas en el Gran Caribe, WIDECAST, Apdo. 50.789, Caracas 1050-A (Venezuela); Doyle, Emma [5 Woodvale Close, St. Ives, N.S.W. 2075 (Australia)

    2008-10-15

    Human exploitation of sea turtles in Venezuela dates back at least 800 years and continues to the present day. The first concerns about the status of sea turtle populations arose in the 1970s, and the projects from this early era were a tagging program, beach evaluation and in situ nest protection. Since then, efforts to develop a sea turtle research and conservation sector in Venezuela have resulted in a number of successes and rather more failures. Among the achievements is a course 'Sea Turtle Biology and Conservation Techniques', which has now been run for 15 years and has educated several hundred participants and enabled the establishment of a valuable professional network, and the publication of the Venezuelan 'Sea Turtle Recovery Action Plan' in 2000. But Venezuela shares with other developing countries some crucial shortcomings which have restricted the success of conservation and research efforts. Whilst regulations relating to protected areas and natural resource use have proliferated, enforcement is weak. Community-based projects and environmental education programs exist, but levels of participation are low. A large number of conservation approaches have been applied, including head-starting and nest translocation to hatcheries, but their value as conservation tools remains unproven. Research has increased, but its impact on decision-making is not significant. Taking an insider's perspective on the challenges to date in sea turtle research and conservation in Venezuela reveals much about the reality facing conservation scientists in developing countries and the forces that shape and can potentially derail research and conservation efforts.

  9. Conservation science in developing countries: an inside perspective on the struggles in sea turtle research and conservation in Venezuela

    International Nuclear Information System (INIS)

    Buitrago, Joaquin; Guada, Hedelvy J.; Doyle, Emma

    2008-01-01

    Human exploitation of sea turtles in Venezuela dates back at least 800 years and continues to the present day. The first concerns about the status of sea turtle populations arose in the 1970s, and the projects from this early era were a tagging program, beach evaluation and in situ nest protection. Since then, efforts to develop a sea turtle research and conservation sector in Venezuela have resulted in a number of successes and rather more failures. Among the achievements is a course 'Sea Turtle Biology and Conservation Techniques', which has now been run for 15 years and has educated several hundred participants and enabled the establishment of a valuable professional network, and the publication of the Venezuelan 'Sea Turtle Recovery Action Plan' in 2000. But Venezuela shares with other developing countries some crucial shortcomings which have restricted the success of conservation and research efforts. Whilst regulations relating to protected areas and natural resource use have proliferated, enforcement is weak. Community-based projects and environmental education programs exist, but levels of participation are low. A large number of conservation approaches have been applied, including head-starting and nest translocation to hatcheries, but their value as conservation tools remains unproven. Research has increased, but its impact on decision-making is not significant. Taking an insider's perspective on the challenges to date in sea turtle research and conservation in Venezuela reveals much about the reality facing conservation scientists in developing countries and the forces that shape and can potentially derail research and conservation efforts

  10. Modelling and predicting biogeographical patterns in river networks

    Directory of Open Access Journals (Sweden)

    Sabela Lois

    2016-04-01

    Full Text Available Statistical analysis and interpretation of biogeographical phenomena in rivers is now possible using a spatially explicit modelling framework, which has seen significant developments in the past decade. I used this approach to identify a spatial extent (geostatistical range in which the abundance of the parasitic freshwater pearl mussel (Margaritifera margaritifera L. is spatially autocorrelated in river networks. I show that biomass and abundance of host fish are a likely explanation for the autocorrelation in mussel abundance within a 15-km spatial extent. The application of universal kriging with the empirical model enabled precise prediction of mussel abundance within segments of river networks, something that has the potential to inform conservation biogeography. Although I used a variety of modelling approaches in my thesis, I focus here on the details of this relatively new spatial stream network model, thus advancing the study of biogeographical patterns in river networks.

  11. An energy-efficient leader election mechanism for wireless body area networks

    OpenAIRE

    Zhang , Rongrong; Moungla , Hassine; Mehaoua , Ahmed

    2014-01-01

    International audience; In Wireless Body Area Networks (WBANs), the energy consumption determines the lifetime of the entire network. As a result, how to conserve the energy to prolong the network lifetime becomes a key problem in WBANs. In this paper, to address the energy conservation problem in WBANs, we develop an Energy-Efficient Leader Election mechanism, called EELE. In EELE, each node competes for the leader following the distributed leader election algorithm in which a utility functi...

  12. Multiple network alignment on quantum computers

    Science.gov (United States)

    Daskin, Anmer; Grama, Ananth; Kais, Sabre

    2014-12-01

    Comparative analyses of graph-structured datasets underly diverse problems. Examples of these problems include identification of conserved functional components (biochemical interactions) across species, structural similarity of large biomolecules, and recurring patterns of interactions in social networks. A large class of such analyses methods quantify the topological similarity of nodes across networks. The resulting correspondence of nodes across networks, also called node alignment, can be used to identify invariant subgraphs across the input graphs. Given graphs as input, alignment algorithms use topological information to assign a similarity score to each -tuple of nodes, with elements (nodes) drawn from each of the input graphs. Nodes are considered similar if their neighbors are also similar. An alternate, equivalent view of these network alignment algorithms is to consider the Kronecker product of the input graphs and to identify high-ranked nodes in the Kronecker product graph. Conventional methods such as PageRank and HITS (Hypertext-Induced Topic Selection) can be used for this purpose. These methods typically require computation of the principal eigenvector of a suitably modified Kronecker product matrix of the input graphs. We adopt this alternate view of the problem to address the problem of multiple network alignment. Using the phase estimation algorithm, we show that the multiple network alignment problem can be efficiently solved on quantum computers. We characterize the accuracy and performance of our method and show that it can deliver exponential speedups over conventional (non-quantum) methods.

  13. Quality of governance and effectiveness of protected areas: crucial concepts for conservation planning.

    Science.gov (United States)

    Eklund, Johanna; Cabeza, Mar

    2017-07-01

    Protected areas (PAs) are a key tool for biodiversity conservation and play a central role in the Convention on Biological Diversity. Recently, the effectiveness of PAs has been questioned, and assessing how effective they are in enabling the future persistence of biodiversity is not trivial. Here, we focus on terrestrial PAs and clarify the terminology related to PA effectiveness, distinguishing between management and ecological aspects. We suggest that the quality of governance affects both aspects of effectiveness but recognize a lack of synthetic understanding of the topic. We present a conceptual framework linking the underlying mechanisms by which the quality of governance affects conservation outcomes in PAs and how this relates to conservation planning. We show that it is crucial to separate pressure and response and how these together will lead to the observed conservation outcomes. We urge for more focused attention on governance factors and in particular more empirical research on how to address causality and how to account for the quality of governance when prioritizing actions. Our framework is linked to the classic concepts of systematic conservation planning and clarifies the strategies available to achieve a comprehensive and effective network of PAs. © 2016 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals, Inc. on behalf of New York Academy of Sciences.

  14. Can rice field channels contribute to biodiversity conservation in Southern Brazilian wetlands?

    Science.gov (United States)

    Maltchik, Leonardo; Rolon, Ana Silvia; Stenert, Cristina; Machado, Iberê Farina; Rocha, Odete

    2011-12-01

    Conservation of species in agroecosystems has attracted attention. Irrigation channels can improve habitats and offer conditions for freshwater species conservation. Two questions from biodiversity conservation point of view are: 1) Can the irrigated channels maintain a rich diversity of macrophytes, macroinvertebrates and amphibians over the cultivation cycle? 2) Do richness, abundance and composition of aquatic species change over the rice cultivation cycle? For this, a set of four rice field channels was randomly selected in Southern Brazilian wetlands. In each channel, six sample collection events were carried out over the rice cultivation cycle (June 2005 to June 2006). A total of 160 taxa were identified in irrigated channels, including 59 macrophyte species, 91 taxa of macroinvertebrate and 10 amphibian species. The richness and abundance of macrophytes, macroinvertebrates and amphibians did not change significantly over the rice cultivation cycle. However, the species composition of these groups in the irrigation channels varied between uncultivated and cultivated periods. Our results showed that the species diversity found in the irrigation channels, together with the permanence of water enables these man-made aquatic networks to function as important systems that can contribute to the conservation of biodiversity in regions where the wetlands were converted into rice fields. The conservation of the species in agriculture, such as rice field channels, may be an important alternative for biodiversity conservation in Southern Brazil, where more than 90% of wetland systems have already been lost and the remaining ones are still at high risk due to the expansion of rice production.

  15. Handbook on energy conservation

    International Nuclear Information System (INIS)

    1989-12-01

    This book shows energy situation in recent years, which includes reserves of energy resource in the world, crude oil production records in OPEC and non OPEC, supply and demand of energy in important developed countries, prospect of supply and demand of energy and current situation of energy conservation in developed countries. It also deals with energy situation in Korea reporting natural resources status, energy conservation policy, measurement for alternative energy, energy management of Korea, investment in equipment and public education for energy conservation.

  16. A Study on an Energy Conservation and Interconnection Scheme between WSN and Internet Based on the 6LoWPAN

    Directory of Open Access Journals (Sweden)

    Runtong Zhang

    2015-01-01

    Full Text Available Wireless sensor network (WSN, which has broad application prospects, consists of small nodes with sensing, computation, and communications capabilities. IPv6 is used over low power WPAN (wireless personal area network which is run by 6LoWPAN technology on the LoWPAN devices. In order to establish seamless connection of two heterogeneous networks, that is, WSN and IPv6 network, this paper proposes an improved energy conservation and interconnection scheme (ECIS based on the analysis of the current schemes. Detailed design of each functional component in the new scheme is proposed, and an expansion of the SSCS module in NS2 802.15.4 simulator is examined. Comprehensive experiments on the simulation platform show that the newly proposed scheme is advantageous over existing results.

  17. Exploring the miRNA regulatory network using evolutionary correlations.

    Directory of Open Access Journals (Sweden)

    Benedikt Obermayer

    2014-10-01

    Full Text Available Post-transcriptional regulation by miRNAs is a widespread and highly conserved phenomenon in metazoans, with several hundreds to thousands of conserved binding sites for each miRNA, and up to two thirds of all genes under miRNA regulation. At the same time, the effect of miRNA regulation on mRNA and protein levels is usually quite modest and associated phenotypes are often weak or subtle. This has given rise to the notion that the highly interconnected miRNA regulatory network exerts its function less through any individual link and more via collective effects that lead to a functional interdependence of network links. We present a Bayesian framework to quantify conservation of miRNA target sites using vertebrate whole-genome alignments. The increased statistical power of our phylogenetic model allows detection of evolutionary correlation in the conservation patterns of site pairs. Such correlations could result from collective functions in the regulatory network. For instance, co-conservation of target site pairs supports a selective benefit of combinatorial regulation by multiple miRNAs. We find that some miRNA families are under pronounced co-targeting constraints, indicating a high connectivity in the regulatory network, while others appear to function in a more isolated way. By analyzing coordinated targeting of different curated gene sets, we observe distinct evolutionary signatures for protein complexes and signaling pathways that could reflect differences in control strategies. Our method is easily scalable to analyze upcoming larger data sets, and readily adaptable to detect high-level selective constraints between other genomic loci. We thus provide a proof-of-principle method to understand regulatory networks from an evolutionary perspective.

  18. Almost conserved operators in nearly many-body localized systems

    Science.gov (United States)

    Pancotti, Nicola; Knap, Michael; Huse, David A.; Cirac, J. Ignacio; Bañuls, Mari Carmen

    2018-03-01

    We construct almost conserved local operators, that possess a minimal commutator with the Hamiltonian of the system, near the many-body localization transition of a one-dimensional disordered spin chain. We collect statistics of these slow operators for different support sizes and disorder strengths, both using exact diagonalization and tensor networks. Our results show that the scaling of the average of the smallest commutators with the support size is sensitive to Griffiths effects in the thermal phase and the onset of many-body localization. Furthermore, we demonstrate that the probability distributions of the commutators can be analyzed using extreme value theory and that their tails reveal the difference between diffusive and subdiffusive dynamics in the thermal phase.

  19. 77 FR 29637 - Game Show Network, LLC v. Cablevision Systems Corp.

    Science.gov (United States)

    2012-05-18

    ... Affairs Bureau at (202) 418-0530 (voice), (202) 418-0432 (TTY). Synopsis of the Order I. Introduction 1... its affiliated cable networks (American Movie Classics (AMC), Fuse, Independent Film Channel, WE tv...

  20. Principles of the Energy Conservation Bill

    International Nuclear Information System (INIS)

    Zeman, J.

    1995-01-01

    The paper describes 21 principles of the draft Energy Conservation Bill. The principles lay down fundamental responsibilities of the government, the municipalities, business entities, citizens and power plants in the field of economical energy management. Included are principles to minimize energy consumption and to stimulate a reasonable energy management, the role of the energy distribution network, responsibilities of the central load dispatching center, and power plant output regulation schemes. (J.B.)

  1. Wildlife conservation and rail track monitoring using wireless sensor networks

    DEFF Research Database (Denmark)

    Mathur, Prateek; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2014-01-01

    n this paper we put forward an approach, first of its kind, to collectively address conservation of elephants by preventing their death being overrun by trains and monitoring the integrity of the rail track. It utilizes a unique method for deterring the elephants using infrasonic sound from cross...

  2. Marketing and design of residential energy conservation programs for the elderly

    Energy Technology Data Exchange (ETDEWEB)

    Berry, L.; Schweitzer, M.; Freeman, E.

    1988-02-01

    This report describes barriers to energy conservation by the elderly. Because of these barriers, they have a greater need for programs that assist with the installation of energy-efficiency improvements. In response to this need, a number of specialized programs are operated for the elderly. This report contains descriptions of 39 energy conservation programs for the elderly. Telephone interviews were conducted with the managers of these programs to identify marketing techniques and organizational structures. Interagency networking, presentations and referrals are the most common methods of recruiting clients. Other marketing techniques in order of the frequency of use are: direct mail, bill inserts, television, radio, printed materials, and telemarketing. Many managers consider word-of-mouth advertising from satisfied clients the most effective form of marketing. Interagency networking and support (financial, structural and in-kind) can offer real advantages in the operation of conservation programs for the elderly. The use of specific marketing techniques is probably less important to success in recruiting clients than the degree of trust potential clients have in the sponsoring organization(s). 4 figs., 10 tabs.

  3. Identification of important nodes in directed biological networks: a network motif approach.

    Directory of Open Access Journals (Sweden)

    Pei Wang

    Full Text Available Identification of important nodes in complex networks has attracted an increasing attention over the last decade. Various measures have been proposed to characterize the importance of nodes in complex networks, such as the degree, betweenness and PageRank. Different measures consider different aspects of complex networks. Although there are numerous results reported on undirected complex networks, few results have been reported on directed biological networks. Based on network motifs and principal component analysis (PCA, this paper aims at introducing a new measure to characterize node importance in directed biological networks. Investigations on five real-world biological networks indicate that the proposed method can robustly identify actually important nodes in different networks, such as finding command interneurons, global regulators and non-hub but evolutionary conserved actually important nodes in biological networks. Receiver Operating Characteristic (ROC curves for the five networks indicate remarkable prediction accuracy of the proposed measure. The proposed index provides an alternative complex network metric. Potential implications of the related investigations include identifying network control and regulation targets, biological networks modeling and analysis, as well as networked medicine.

  4. Marine Spatial Planning in a Transboundary Context: Linking Baja California with California's Network of Marine Protected Areas

    Directory of Open Access Journals (Sweden)

    Nur Arafeh-Dalmau

    2017-05-01

    Full Text Available It is acknowledged that an effective path to globally protect marine ecosystems is through the establishment of eco-regional scale networks of MPAs spanning across national frontiers. In this work we aimed to plan for regionally feasible networks of MPAs that can be ecologically linked with an existing one in a transboundary context. We illustrate our exercise in the Ensenadian eco-region, a shared marine ecosystem between the south of California, United States of America (USA, and the north of Baja California, Mexico; where conservation actions differ across the border. In the USA, California recently established a network of MPAs through the Marine Life Protection Act (MLPA, while in Mexico: Baja California lacks a network of MPAs or a marine spatial planning effort to establish it. We generated four different scenarios with Marxan by integrating different ecological, social, and management considerations (habitat representation, opportunity costs, habitat condition, and enforcement costs. To do so, we characterized and collected biophysical and socio-economic information for Baja California and developed novel approaches to quantify and incorporate some of these considerations. We were able to design feasible networks of MPAs in Baja California that are ecologically linked with California's network (met between 78.5 and 84.4% of the MLPA guidelines and that would represent a low cost for fishers and aquaculture investors. We found that when multiple considerations are integrated more priority areas for conservation emerge. For our region, human distribution presents a strong gradient from north to south and resulted to be an important factor for the spatial arrangement of the priority areas. This work shows how, despite the constraints of a data-poor area, the available conservation principles, mapping, and planning tools can still be used to generate spatial conservation plans in a transboundary context.

  5. Optimal traffic control in highway transportation networks using linear programming

    KAUST Repository

    Li, Yanning

    2014-06-01

    This article presents a framework for the optimal control of boundary flows on transportation networks. The state of the system is modeled by a first order scalar conservation law (Lighthill-Whitham-Richards PDE). Based on an equivalent formulation of the Hamilton-Jacobi PDE, the problem of controlling the state of the system on a network link in a finite horizon can be posed as a Linear Program. Assuming all intersections in the network are controllable, we show that the optimization approach can be extended to an arbitrary transportation network, preserving linear constraints. Unlike previously investigated transportation network control schemes, this framework leverages the intrinsic properties of the Halmilton-Jacobi equation, and does not require any discretization or boolean variables on the link. Hence this framework is very computational efficient and provides the globally optimal solution. The feasibility of this framework is illustrated by an on-ramp metering control example.

  6. Conservation policies and planning under climate change

    DEFF Research Database (Denmark)

    Strange, Niels; Thorsen, Bo Jellesmark; Bladt, Jesper Stentoft

    2011-01-01

    Biodiversity conservation policies focus on securing the survival of species and habitats according to their current distribution. This basic premise may be inappropriate for halting biodiversity decline under the dynamic changes caused by climate change. This study explores a dynamic spatial...... conservation prioritization problem where climate change gradually changes the future habitat suitability of a site’ current species. This has implications for survival probability, as well as for species that potentially immigrate to the site. The problem is explored using a set of heuristics for both of two...... networks. Climate change induced shifts in the suitability of habitats for species may increase the value of such adaptive strategies, the benefit decreasing with increasing migration probabilities and species distribution dynamics....

  7. Network Design with Node Degree Balance Constraints

    DEFF Research Database (Denmark)

    Pedersen, Michael Berliner; Crainic, Teodor Gabriel

    This presentation discusses an extension to the network design model where there in addition to the flow conservation constraints also are constraints that require design conservation. This means that the number of arcs entering and leaving a node must be the same. As will be shown the model has ...

  8. Networking Nature, or Serengeti Behind the Dikes

    NARCIS (Netherlands)

    Belt, van den H.

    2004-01-01

    Nowadays, wildlife has no chance to be conserved and maintained without the helping hand of man. Ambitious plans to adopt an offensive rather than defensive approach to conservation by creating ‘new nature’ led to initiatives to build ecological networks, from the local, through the regional and the

  9. Conserved regulators of nucleolar size revealed by global phenotypic analyses.

    Science.gov (United States)

    Neumüller, Ralph A; Gross, Thomas; Samsonova, Anastasia A; Vinayagam, Arunachalam; Buckner, Michael; Founk, Karen; Hu, Yanhui; Sharifpoor, Sara; Rosebrock, Adam P; Andrews, Brenda; Winston, Fred; Perrimon, Norbert

    2013-08-20

    Regulation of cell growth is a fundamental process in development and disease that integrates a vast array of extra- and intracellular information. A central player in this process is RNA polymerase I (Pol I), which transcribes ribosomal RNA (rRNA) genes in the nucleolus. Rapidly growing cancer cells are characterized by increased Pol I-mediated transcription and, consequently, nucleolar hypertrophy. To map the genetic network underlying the regulation of nucleolar size and of Pol I-mediated transcription, we performed comparative, genome-wide loss-of-function analyses of nucleolar size in Saccharomyces cerevisiae and Drosophila melanogaster coupled with mass spectrometry-based analyses of the ribosomal DNA (rDNA) promoter. With this approach, we identified a set of conserved and nonconserved molecular complexes that control nucleolar size. Furthermore, we characterized a direct role of the histone information regulator (HIR) complex in repressing rRNA transcription in yeast. Our study provides a full-genome, cross-species analysis of a nuclear subcompartment and shows that this approach can identify conserved molecular modules.

  10. Conserved Regulators of Nucleolar Size Revealed by Global Phenotypic Analyses

    Science.gov (United States)

    Neumüller, Ralph A.; Gross, Thomas; Samsonova, Anastasia A.; Vinayagam, Arunachalam; Buckner, Michael; Founk, Karen; Hu, Yanhui; Sharifpoor, Sara; Rosebrock, Adam P.; Andrews, Brenda; Winston, Fred; Perrimon, Norbert

    2014-01-01

    Regulation of cell growth is a fundamental process in development and disease that integrates a vast array of extra- and intracellular information. A central player in this process is RNA polymerase I (Pol I), which transcribes ribosomal RNA (rRNA) genes in the nucleolus. Rapidly growing cancer cells are characterized by increased Pol I–mediated transcription and, consequently, nucleolar hypertrophy. To map the genetic network underlying the regulation of nucleolar size and of Pol I–mediated transcription, we performed comparative, genome-wide loss-of-function analyses of nucleolar size in Saccharomyces cerevisiae and Drosophila melanogaster coupled with mass spectrometry–based analyses of the ribosomal DNA (rDNA) promoter. With this approach, we identified a set of conserved and nonconserved molecular complexes that control nucleolar size. Furthermore, we characterized a direct role of the histone information regulator (HIR) complex in repressing rRNA transcription in yeast. Our study provides a full-genome, cross-species analysis of a nuclear subcompartment and shows that this approach can identify conserved molecular modules. PMID:23962978

  11. Conservation of Charge and Conservation of Current

    OpenAIRE

    Eisenberg, Bob

    2016-01-01

    Conservation of current and conservation of charge are nearly the same thing: when enough is known about charge movement, conservation of current can be derived from conservation of charge, in ideal dielectrics, for example. Conservation of current is enforced implicitly in ideal dielectrics by theories that conserve charge. But charge movement in real materials like semiconductors or ionic solutions is never ideal. We present an apparently universal derivation of conservation of current and ...

  12. Conservation of living resources in a changing world

    Science.gov (United States)

    Teer, James G.

    1996-11-01

    Conservation of living resources is no longer parochial in scope; it is a global challenge. Ecological, social, political, and business interests operate in a network that reaches across seas, continents, and nations. Industries, including the electric utility industry, are diversifying in products and expanding into international markets. They soon discover that, while all nations have common goals for their peoples, conservation and environmental issues in less-developed nations have different dimensions and norms than are encountered in Western, affluent societies. In developing countries, survival is more of an issue than quality of life, and burgeoning human numbers have put tremendous pressures on resources including wildlife and its habitats. Human population, urbanization of society, changes in single-species to ecosystem and landscape levels of management, and protectionists and animal rights philosophies are influences with which conservation of resources and the environment must contend. The human condition and conservation efforts are inextricably linked. Examples to demonstrate this fact are given for Project Tiger in India, the jaguar in Latin America, and the Serengeti ecosystem in Kenya and Tanzania.

  13. Two-level Robust Measurement Fusion Kalman Filter for Clustering Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Peng; QI Wen-Juan; DENG Zi-Li

    2014-01-01

    This paper investigates the distributed fusion Kalman filtering over clustering sensor networks. The sensor network is partitioned as clusters by the nearest neighbor rule and each cluster consists of sensing nodes and cluster-head. Using the minimax robust estimation principle, based on the worst-case conservative system with the conservative upper bounds of noise variances, two-level robust measurement fusion Kalman filter is presented for the clustering sensor network systems with uncertain noise variances. It can significantly reduce the communication load and save energy when the number of sensors is very large. A Lyapunov equation approach for the robustness analysis is presented, by which the robustness of the local and fused Kalman filters is proved. The concept of the robust accuracy is presented, and the robust accuracy relations among the local and fused robust Kalman filters are proved. It is proved that the robust accuracy of the two-level weighted measurement fuser is equal to that of the global centralized robust fuser and is higher than those of each local robust filter and each local weighted measurement fuser. A simulation example shows the correctness and effectiveness of the proposed results.

  14. A Global Network Alignment Method Using Discrete Particle Swarm Optimization.

    Science.gov (United States)

    Huang, Jiaxiang; Gong, Maoguo; Ma, Lijia

    2016-10-19

    Molecular interactions data increase exponentially with the advance of biotechnology. This makes it possible and necessary to comparatively analyse the different data at a network level. Global network alignment is an important network comparison approach to identify conserved subnetworks and get insight into evolutionary relationship across species. Network alignment which is analogous to subgraph isomorphism is known to be an NP-hard problem. In this paper, we introduce a novel heuristic Particle-Swarm-Optimization based Network Aligner (PSONA), which optimizes a weighted global alignment model considering both protein sequence similarity and interaction conservations. The particle statuses and status updating rules are redefined in a discrete form by using permutation. A seed-and-extend strategy is employed to guide the searching for the superior alignment. The proposed initialization method "seeds" matches with high sequence similarity into the alignment, which guarantees the functional coherence of the mapping nodes. A greedy local search method is designed as the "extension" procedure to iteratively optimize the edge conservations. PSONA is compared with several state-of-art methods on ten network pairs combined by five species. The experimental results demonstrate that the proposed aligner can map the proteins with high functional coherence and can be used as a booster to effectively refine the well-studied aligners.

  15. Role of New Nature Reserve in Assisting Endangered Species Conservation - Case Study of Giant Pandas in the Northern Qionglai Mountains, China.

    Directory of Open Access Journals (Sweden)

    Tian-Pei Guan

    Full Text Available The creation of nature reserves is the most direct way to save endangered species populations and their habitat. Development of the giant panda (Ailuropoda melanoleuca nature reserve network in China was initiated in the 1960s, though the effort to create new reserves boomed considerably after the year 2000. Given this rapid development of protected areas in panda habitats, and the potential conflicting interests between conservation administrations and local economic development, it is essential to assess the role of new nature reserves in the overall giant panda conservation effort and reserve network. We utilized data from national giant panda surveys conducted in 2000 and 2012 to compare the size, spatial use, and distribution of panda populations, as well as the habitat suitability and connectivity in the Northern Qionglai Mountains between the two survey years. Our results show that although the total giant panda population in the study area did not change remarkably, local changes did occur. Most notably, the population in Wolong Nature Reserve declined by 27.3% (N = 39 and the population in Caopo Nature Reserve increased by 71.4% (N = 29 over the 12-year study period. We also found habitat suitability and availability decreased in both Wolong (12.4% and Caopo (7.4%, but that the relative density of giant pandas declined (19.2% and increased (84.6% at each site, respectively. The distance between centers of high IUA were more distant in 2012 (14.1±1.9km than that in 2000 (6.1±0.9km; t = -7.4, df = 5, p = 0.001, showing a scattered spatial pattern. Habitat availability decreased by 42% within the corridor between the two reserves, however panda occurrences in the corridor increased 24.6%. Compared to the total number of encounters, the proportion of the corridor increased 45.76%. Our results show the importance and success of the newly established Caopo to the conservation of giant pandas, and how crucial it is to identify and repair

  16. Constructing Conservation Impact: Understanding Monitoring and Evaluation in Conservation NGOs

    Directory of Open Access Journals (Sweden)

    Catherine Benson Wahlén

    2014-01-01

    Full Text Available A growing number of scholars critically examine large conservation organisations to explore organisational intentions, practices, and outcomes. In parallel, other scholars have problematised audit cultures, suggesting that these seemingly good practices of evaluation and measurement are not neutral and instead have consequences for governance and power. This article combines literature on conservation NGOs, organisational theory, and audit culture to study the inner workings of conservation and to understand the construction of effectiveness and impact. I draw on semi-structured interviews to examine how a large, international conservation organisation, which I term the World Conservation Organisation (WCO; a pseudonym, coordinates monitoring and evaluation (M&E processes among its international, national, and local offices. I find individual staff within WCO make varying assumptions about the M&E policies and place different values on M&E, which results in different institutional logics towards M&E and a broader organisational failure to measure progress and reflect upon outcomes. The findings also show difficulties in translating broad organisational goals into specific project activities, underscoring tensions in implementation and limitations in M&E practice. I also find that organisational and managerial pressure to report success is greater than donor pressure, a finding that expands understandings of NGO-donor dynamics.

  17. Representing connectivity: quantifying effective habitat availability based on area and connectivity for conservation status assessment and recovery.

    Science.gov (United States)

    Neel, Maile; Tumas, Hayley R; Marsden, Brittany W

    2014-01-01

    We apply a comprehensive suite of graph theoretic metrics to illustrate how landscape connectivity can be effectively incorporated into conservation status assessments and in setting conservation objectives. These metrics allow conservation practitioners to evaluate and quantify connectivity in terms of representation, resiliency, and redundancy and the approach can be applied in spite of incomplete knowledge of species-specific biology and dispersal processes. We demonstrate utility of the graph metrics by evaluating changes in distribution and connectivity that would result from implementing two conservation plans for three endangered plant species (Erigeron parishii, Acanthoscyphus parishii var. goodmaniana, and Eriogonum ovalifolium var. vineum) relative to connectivity under current conditions. Although distributions of the species differ from one another in terms of extent and specific location of occupied patches within the study landscape, the spatial scale of potential connectivity in existing networks were strikingly similar for Erigeron and Eriogonum, but differed for Acanthoscyphus. Specifically, patches of the first two species were more regularly distributed whereas subsets of patches of Acanthoscyphus were clustered into more isolated components. Reserves based on US Fish and Wildlife Service critical habitat designation would not greatly contribute to maintain connectivity; they include 83-91% of the extant occurrences and >92% of the aerial extent of each species. Effective connectivity remains within 10% of that in the whole network for all species. A Forest Service habitat management strategy excluded up to 40% of the occupied habitat of each species resulting in both range reductions and loss of occurrences from the central portions of each species' distribution. Overall effective network connectivity was reduced to 62-74% of the full networks. The distance at which each CHMS network first became fully connected was reduced relative to the full

  18. Tourism and Conservation

    DEFF Research Database (Denmark)

    Budeanu, Adriana

    2017-01-01

    Tourism is promoted by policy makers and international organizations as a tool for advancing conservation agendas, while contributing to poverty alleviation and human development, under the banner of ecotourism or sustainable tourism. However, the indiscriminating use of complex and ambiguous...... concepts such as “poverty” and “sustainability” hide important nuances with regards to the variety of processes and subsequent effects that are triggered when tourism and conservation are being adjoined. Experiences with tourism developments show that destinations that are weak economically find it harder...... to draw benefits from tourism developments or to decline participation in tourism with only little or no losses of sources of income and wealth. If tourism should fulfil sustainability goals related to conservation, poverty, and human development, it needs consistent governmental intervention...

  19. Tests of peak flow scaling in simulated self-similar river networks

    Science.gov (United States)

    Menabde, M.; Veitzer, S.; Gupta, V.; Sivapalan, M.

    2001-01-01

    The effect of linear flow routing incorporating attenuation and network topology on peak flow scaling exponent is investigated for an instantaneously applied uniform runoff on simulated deterministic and random self-similar channel networks. The flow routing is modelled by a linear mass conservation equation for a discrete set of channel links connected in parallel and series, and having the same topology as the channel network. A quasi-analytical solution for the unit hydrograph is obtained in terms of recursion relations. The analysis of this solution shows that the peak flow has an asymptotically scaling dependence on the drainage area for deterministic Mandelbrot-Vicsek (MV) and Peano networks, as well as for a subclass of random self-similar channel networks. However, the scaling exponent is shown to be different from that predicted by the scaling properties of the maxima of the width functions. ?? 2001 Elsevier Science Ltd. All rights reserved.

  20. A Quantification of the Energy Savings by Conservation Voltage Reduction

    NARCIS (Netherlands)

    Ellens, W.; Berry, A.; West, S.

    2013-01-01

    The introduction of `Smart grid' technologies in the electricity supply industry has attracted new attention to Conservation Voltage Reduction (CVR). CVR is a method that aims to save energy by reducing the voltage level of the electrical distribution network. However, not all devices consume less

  1. Advances in Energy Conservation of China Steel Industry

    Directory of Open Access Journals (Sweden)

    Wenqiang Sun

    2013-01-01

    Full Text Available The course, technical progresses, and achievements of energy conservation of China steel industry (CSI during 1980–2010 were summarized. Then, the paper adopted e-p method to analyze the variation law and influencing factors of energy consumptions of large- and medium-scale steel plants within different stages. It is pointed out that energy consumption per ton of crude steel has been almost one half lower in these thirty years, with 60% as direct energy conservation owing to the change of process energy consumption and 40% as indirect energy conservation attributed to the adjustment of production structure. Next, the latest research progress of some key common technologies in CSI was introduced. Also, the downtrend of energy consumption per ton of crude steel and the potential energy conservation for CSI during 2011–2025 were forecasted. Finally, it is indicated that the key topic of the next 15 years’ research on the energy conservation of CSI is the synergistic operation of material flow and energy flow. It could be achieved by the comprehensive study on energy flow network optimization, such as production, allocation, utilization, recovery, reuse, and resource, according to the energy quantity, quality, and user demand following the first and second laws of thermodynamics.

  2. Advances in energy conservation of China steel industry.

    Science.gov (United States)

    Sun, Wenqiang; Cai, Jiuju; Ye, Zhu

    2013-01-01

    The course, technical progresses, and achievements of energy conservation of China steel industry (CSI) during 1980-2010 were summarized. Then, the paper adopted e-p method to analyze the variation law and influencing factors of energy consumptions of large- and medium-scale steel plants within different stages. It is pointed out that energy consumption per ton of crude steel has been almost one half lower in these thirty years, with 60% as direct energy conservation owing to the change of process energy consumption and 40% as indirect energy conservation attributed to the adjustment of production structure. Next, the latest research progress of some key common technologies in CSI was introduced. Also, the downtrend of energy consumption per ton of crude steel and the potential energy conservation for CSI during 2011-2025 were forecasted. Finally, it is indicated that the key topic of the next 15 years' research on the energy conservation of CSI is the synergistic operation of material flow and energy flow. It could be achieved by the comprehensive study on energy flow network optimization, such as production, allocation, utilization, recovery, reuse, and resource, according to the energy quantity, quality, and user demand following the first and second laws of thermodynamics.

  3. The UNESCO Global Network of National Geoparks

    Science.gov (United States)

    Mc Keever1, P.; Zouros, N.; Patzak, M.; Missotten, R.

    2009-12-01

    The UNESCO Global Network of National Geoparks was founded in 2004, following the model successfully established by the European Geoparks Network in 2000. It now comprises 63 members in 19 nations across the world. A Global Geopark is an area with geological heritage of international value but where that heritage is being used for the sustainable economic benefit if the local inhabitants, primarily through education and tourism. Supported by IUGS and IUCN, the aim of the Global Geoparks Network is to facilitate exchange and sharing between members to assist in the protection and conservation of the geological heritage of our planet but to do so in way where local communities can take ownership of these special places and where they can get some sustainable economic benefit from them. While allowing for the sustainable economic development of geoparks, the network explicitly forbids the destruction or sale of the geological value of a geopark. This paper outlines the ethos of the Global Geoparks Network and describes the typical activities of geoparks and how the network functions. Using two examples it also illustrates how members of the Global Geoparks Network provide good examples as tools not only for holistic nature conservation but also for economic development.

  4. Graphical reduction of reaction networks by linear elimination of species

    DEFF Research Database (Denmark)

    Saez Cornellana, Meritxell; Wiuf, Carsten; Feliu, Elisenda

    2017-01-01

    We give a graphically based procedure to reduce a reaction network to a smaller reaction network with fewer species after linear elimination of a set of noninteracting species. We give a description of the reduced reaction network, its kinetics and conservations laws, and explore properties...

  5. Zoos through the Lens of the IUCN Red List: A Global Metapopulation Approach to Support Conservation Breeding Programs

    OpenAIRE

    Conde, Dalia A.; Colchero, Fernando; Gusset, Markus; Pearce-Kelly, Paul; Byers, Onnie; Flesness, Nate; Browne, Robert K.; Jones, Owen R.

    2013-01-01

    Given current extinction trends, the number of species requiring conservation breeding programs (CBPs) is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23%) terrestrial vertebrate species in ISIS zoos are threate...

  6. Conservation of mayflies (Insecta, Ephemeroptera in Espírito Santo, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Fabiana Criste Massariol

    2014-12-01

    Full Text Available Conservation of mayflies (Insecta, Ephemeroptera in Espírito Santo, southeastern Brazil. Ephemeroptera exhibits great diversity among bodies of freshwater in the Atlantic Forest, a biome that is suffering from massive human impact. Within this context, the creation of conservation units using biological information is more recommended than economic, cultural, or political criteria. The distribution pattern of 76 Ephemeroptera species was analyzed using the biogeographical methods Parsimony Analysis of Endemicity and Network Analysis Method in order to infer relevant areas for conservation of the mayfly community in Espírito Santo. The results obtained from both analyses were largely congruent, and pointed out four relevant areas for conservation: two in the south of the state, where conservation units or priority areas for conservation are well established; and two in the north, a region in the state where little conservation efforts have been historically done. Therefore, based on our analyses on mayflies, we recommend the expansion of the existing APCs or the creation of new APCs on the north of Espírito Santo.

  7. Water Conservation Education with a Rainfall Simulator.

    Science.gov (United States)

    Kok, Hans; Kessen, Shelly

    1997-01-01

    Describes a program in which a rainfall simulator was used to promote water conservation by showing water infiltration, water runoff, and soil erosion. The demonstrations provided a good background for the discussion of issues such as water conservation, crop rotation, and conservation tillage practices. The program raised awareness of…

  8. Communication and control for networked complex systems

    CERN Document Server

    Peng, Chen; Han, Qing-Long

    2015-01-01

    This book reports on the latest advances in the study of Networked Control Systems (NCSs). It highlights novel research concepts on NCSs; the analysis and synthesis of NCSs with special attention to their networked character; self- and event-triggered communication schemes for conserving limited network resources; and communication and control co-design for improving the efficiency of NCSs. The book will be of interest to university researchers, control and network engineers, and graduate students in the control engineering, communication and network sciences interested in learning the core principles, methods, algorithms and applications of NCSs.

  9. Optimization of controllability and robustness of complex networks by edge directionality

    Science.gov (United States)

    Liang, Man; Jin, Suoqin; Wang, Dingjie; Zou, Xiufen

    2016-09-01

    Recently, controllability of complex networks has attracted enormous attention in various fields of science and engineering. How to optimize structural controllability has also become a significant issue. Previous studies have shown that an appropriate directional assignment can improve structural controllability; however, the evolution of the structural controllability of complex networks under attacks and cascading has always been ignored. To address this problem, this study proposes a new edge orientation method (NEOM) based on residual degree that changes the link direction while conserving topology and directionality. By comparing the results with those of previous methods in two random graph models and several realistic networks, our proposed approach is demonstrated to be an effective and competitive method for improving the structural controllability of complex networks. Moreover, numerical simulations show that our method is near-optimal in optimizing structural controllability. Strikingly, compared to the original network, our method maintains the structural controllability of the network under attacks and cascading, indicating that the NEOM can also enhance the robustness of controllability of networks. These results alter the view of the nature of controllability in complex networks, change the understanding of structural controllability and affect the design of network models to control such networks.

  10. Tourism revenue as a conservation tool for threatened birds in protected areas.

    Science.gov (United States)

    Steven, Rochelle; Castley, J Guy; Buckley, Ralf

    2013-01-01

    Many bird populations worldwide are at risk of extinction, and rely heavily on protected area networks for their continued conservation. Tourism to these areas contributes to conservation by generating revenue for management. Here we quantify the contribution of tourism revenue for bird species in the IUCN Red List, using a simple accounting method. Relevant data are available for 90 (16%) of the 562 critically endangered and endangered species. Contributions of tourism to bird conservation are highest, 10-64%, in South America, Africa, and their neighbouring islands. Critically endangered bird species rely on tourism more heavily than endangered species (pmanagement budgets by promoting birdwatching tourism specifically.

  11. Network evolution of body plans.

    Directory of Open Access Journals (Sweden)

    Koichi Fujimoto

    Full Text Available One of the major goals in evolutionary developmental biology is to understand the relationship between gene regulatory networks and the diverse morphologies and their functionalities. Are the diversities solely triggered by random events, or are they inevitable outcomes of an interplay between evolving gene networks and natural selection? Segmentation in arthropod embryogenesis represents a well-known example of body plan diversity. Striped patterns of gene expression that lead to the future body segments appear simultaneously or sequentially in long and short germ-band development, respectively. Moreover, a combination of both is found in intermediate germ-band development. Regulatory genes relevant for stripe formation are evolutionarily conserved among arthropods, therefore the differences in the observed traits are thought to have originated from how the genes are wired. To reveal the basic differences in the network structure, we have numerically evolved hundreds of gene regulatory networks that produce striped patterns of gene expression. By analyzing the topologies of the generated networks, we show that the characteristics of stripe formation in long and short germ-band development are determined by Feed-Forward Loops (FFLs and negative Feed-Back Loops (FBLs respectively, and those of intermediate germ-band development are determined by the interconnections between FFL and negative FBL. Network architectures, gene expression patterns and knockout responses exhibited by the artificially evolved networks agree with those reported in the fly Drosophila melanogaster and the beetle Tribolium castaneum. For other arthropod species, principal network architectures that remain largely unknown are predicted. Our results suggest that the emergence of the three modes of body segmentation in arthropods is an inherent property of the evolving networks.

  12. An evaluation of the multi-state node networks reliability using the traditional binary-state networks reliability algorithm

    International Nuclear Information System (INIS)

    Yeh, W.-C.

    2003-01-01

    A system where the components and system itself are allowed to have a number of performance levels is called the Multi-state system (MSS). A multi-state node network (MNN) is a generalization of the MSS without satisfying the flow conservation law. Evaluating the MNN reliability arises at the design and exploitation stage of many types of technical systems. Up to now, the known existing methods can only evaluate a special MNN reliability called the multi-state node acyclic network (MNAN) in which no cyclic is allowed. However, no method exists for evaluating the general MNN reliability. The main purpose of this article is to show first that each MNN reliability can be solved using any the traditional binary-state networks (TBSN) reliability algorithm with a special code for the state probability. A simple heuristic SDP algorithm based on minimal cuts (MC) for estimating the MNN reliability is presented as an example to show how the TBSN reliability algorithm is revised to solve the MNN reliability problem. To the author's knowledge, this study is the first to discuss the relationships between MNN and TBSN and also the first to present methods to solve the exact and approximated MNN reliability. One example is illustrated to show how the exact MNN reliability is obtained using the proposed algorithm

  13. Immunization of networks with community structure

    International Nuclear Information System (INIS)

    Masuda, Naoki

    2009-01-01

    In this study, an efficient method to immunize modular networks (i.e. networks with community structure) is proposed. The immunization of networks aims at fragmenting networks into small parts with a small number of removed nodes. Its applications include prevention of epidemic spreading, protection against intentional attacks on networks, and conservation of ecosystems. Although preferential immunization of hubs is efficient, good immunization strategies for modular networks have not been established. On the basis of an immunization strategy based on eigenvector centrality, we develop an analytical framework for immunizing modular networks. To this end, we quantify the contribution of each node to the connectivity in a coarse-grained network among modules. We verify the effectiveness of the proposed method by applying it to model and real networks with modular structure.

  14. An Energy Efficient Cooperative Hierarchical MIMO Clustering Scheme for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sungyoung Lee

    2011-12-01

    Full Text Available In this work, we present an energy efficient hierarchical cooperative clustering scheme for wireless sensor networks. Communication cost is a crucial factor in depleting the energy of sensor nodes. In the proposed scheme, nodes cooperate to form clusters at each level of network hierarchy ensuring maximal coverage and minimal energy expenditure with relatively uniform distribution of load within the network. Performance is enhanced by cooperative multiple-input multiple-output (MIMO communication ensuring energy efficiency for WSN deployments over large geographical areas. We test our scheme using TOSSIM and compare the proposed scheme with cooperative multiple-input multiple-output (CMIMO clustering scheme and traditional multihop Single-Input-Single-Output (SISO routing approach. Performance is evaluated on the basis of number of clusters, number of hops, energy consumption and network lifetime. Experimental results show significant energy conservation and increase in network lifetime as compared to existing schemes.

  15. Conserving tropical biodiversity via market forces and spatial targeting.

    Science.gov (United States)

    Bateman, Ian J; Coombes, Emma; Fitzherbert, Emily; Binner, Amy; Bad'ura, Tomáš; Carbone, Chris; Fisher, Brendan; Naidoo, Robin; Watkinson, Andrew R

    2015-06-16

    The recent report from the Secretariat of the Convention on Biological Diversity [(2010) Global Biodiversity Outlook 3] acknowledges that ongoing biodiversity loss necessitates swift, radical action. Protecting undisturbed lands, although vital, is clearly insufficient, and the key role of unprotected, private land owned is being increasingly recognized. Seeking to avoid common assumptions of a social planner backed by government interventions, the present work focuses on the incentives of the individual landowner. We use detailed data to show that successful conservation on private land depends on three factors: conservation effectiveness (impact on target species), private costs (especially reductions in production), and private benefits (the extent to which conservation activities provide compensation, for example, by enhancing the value of remaining production). By examining the high-profile issue of palm-oil production in a major tropical biodiversity hotspot, we show that the levels of both conservation effectiveness and private costs are inherently spatial; varying the location of conservation activities can radically change both their effectiveness and private cost implications. We also use an economic choice experiment to show that consumers' willingness to pay for conservation-grade palm-oil products has the potential to incentivize private producers sufficiently to engage in conservation activities, supporting vulnerable International Union for Conservation of Nature Red Listed species. However, these incentives vary according to the scale and efficiency of production and the extent to which conservation is targeted to optimize its cost-effectiveness. Our integrated, interdisciplinary approach shows how strategies to harness the power of the market can usefully complement existing--and to-date insufficient--approaches to conservation.

  16. Conserving tropical biodiversity via market forces and spatial targeting

    Science.gov (United States)

    Bateman, Ian J.; Coombes, Emma; Fitzherbert, Emily; Binner, Amy; Bad’ura, Tomáš; Carbone, Chris; Fisher, Brendan; Naidoo, Robin; Watkinson, Andrew R.

    2015-01-01

    The recent report from the Secretariat of the Convention on Biological Diversity [(2010) Global Biodiversity Outlook 3] acknowledges that ongoing biodiversity loss necessitates swift, radical action. Protecting undisturbed lands, although vital, is clearly insufficient, and the key role of unprotected, private land owned is being increasingly recognized. Seeking to avoid common assumptions of a social planner backed by government interventions, the present work focuses on the incentives of the individual landowner. We use detailed data to show that successful conservation on private land depends on three factors: conservation effectiveness (impact on target species), private costs (especially reductions in production), and private benefits (the extent to which conservation activities provide compensation, for example, by enhancing the value of remaining production). By examining the high-profile issue of palm-oil production in a major tropical biodiversity hotspot, we show that the levels of both conservation effectiveness and private costs are inherently spatial; varying the location of conservation activities can radically change both their effectiveness and private cost implications. We also use an economic choice experiment to show that consumers' willingness to pay for conservation-grade palm-oil products has the potential to incentivize private producers sufficiently to engage in conservation activities, supporting vulnerable International Union for Conservation of Nature Red Listed species. However, these incentives vary according to the scale and efficiency of production and the extent to which conservation is targeted to optimize its cost-effectiveness. Our integrated, interdisciplinary approach shows how strategies to harness the power of the market can usefully complement existing—and to-date insufficient—approaches to conservation. PMID:26077906

  17. A conserved signaling network monitors delivery of sphingolipids to the plasma membrane in budding yeast.

    Science.gov (United States)

    Clarke, Jesse; Dephoure, Noah; Horecka, Ira; Gygi, Steven; Kellogg, Douglas

    2017-10-01

    In budding yeast, cell cycle progression and ribosome biogenesis are dependent on plasma membrane growth, which ensures that events of cell growth are coordinated with each other and with the cell cycle. However, the signals that link the cell cycle and ribosome biogenesis to membrane growth are poorly understood. Here we used proteome-wide mass spectrometry to systematically discover signals associated with membrane growth. The results suggest that membrane trafficking events required for membrane growth generate sphingolipid-dependent signals. A conserved signaling network appears to play an essential role in signaling by responding to delivery of sphingolipids to the plasma membrane. In addition, sphingolipid-dependent signals control phosphorylation of protein kinase C (Pkc1), which plays an essential role in the pathways that link the cell cycle and ribosome biogenesis to membrane growth. Together these discoveries provide new clues as to how growth--dependent signals control cell growth and the cell cycle. © 2017 Clarke et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  18. Assessing the efficiency of Mediterranean ditch networks in preventing vineyards soil erosion within landscape

    Science.gov (United States)

    Levavasseur, Florent; Bailly, Jean-Stéphane; Lagacherie, Philippe

    2013-04-01

    Water erosion of cultivated soils is a threat to the sustainability of agriculture, especially in Mediterranean areas. For a long time, Mediterranean farmers have thus adopted some soil conservation practices. Actual ditch networks, which are generally associated with terraces, result from historical successive farmer settlements and are one of these soil conservation practices. By intercepting surface run-off, ditches decrease slope length and prevent soil erosion on downstream plots. However, since water erosion hazard and ditch network geometries are highly variable in vineyards landscape and since ditch building and maintaining are costly, the objective of this study was to identify and map the resulting efficiency of ditch networks in preventing soil erosion. For a given area, a ditch network efficiency is defined here as the balance between the network density, i.e. network cumulated length for a given area unit, and the erosion sensitivity over an area which measures the performance of the ditch network in limiting soil erosion. The erosion efficiency of ditch networks was thus identified using both i) computer generated ditch networks with various spatial configurations and ii) the stream power index as an erosion sensitivity indicator, computed from a DTM in which each ditch network was burned. The stream power index of the actual networks were compared with a set of generated networks whose density and topology were selected to maximize the performance in preventing soil erosion thanks to the use of a self-developed optimized stochastic network generator. For four 1 km² hillslopes, we showed that the performances of actual networks to prevent soil erosion was among the best that were obtained by simulated networks with even greater densities. Furthermore, we showed that the stream power index values that accounted for the actual ditch networks to prevent soil erosion hazard was both minimal and weakly variable in the whole study area (30 km²) at

  19. An unconditionally stable fully conservative semi-Lagrangian method

    KAUST Repository

    Lentine, Michael; Gré tarsson, Jó n Tó mas; Fedkiw, Ronald

    2011-01-01

    of the conserved quantity that was not accounted for in the typical semi-Lagrangian advection. We show that this new scheme can be used to conserve both mass and momentum for incompressible flows. For incompressible flows, we further explore properly conserving

  20. An extra power saving scheme for prolonging lifetime of mobile handset in the 4G mobile networks.

    Science.gov (United States)

    Chen, Jenhui; Tarn, Woei-Hwa; Lee, Jiann-Der

    2014-01-01

    In the fourth generation or next generation networks, services of non-real-time variable bit rate (NRT-VBR) and best effort (BE) will dominate over 85% of the total traffic in the networks. In this paper, we study the power saving mechanism of NRT-VBR and BE services for mobile handsets (MHs) to prolong their battery lifetime (i.e., the sustained operation duration) in the fourth generation networks. Because the priority of NRT-VBR and BE is lower than that of real-time VBR (RT-VBR) or guaranteed bit rate (GBR) services, we investigate an extended sleep mode for lower priority services (e.g., NRT-VBR and BE) in an MH to conserve the energy. The extended sleep mode is used when the MH wakes up from the sleep mode but it cannot obtain the bandwidth from base station (BS). The proposed mechanism, named extra power saving scheme (EPSS), uses the M/M/k/k Markovian queuing model to estimate the extended sleep duration to let MHs conserve their battery energy when the networks traffic is congested. To study the performance of EPSS, an accurate analysis model of energy is presented and validated by taking a series of simulations. Numerical experiments show that EPSS can achieve 43% extra energy conservation at most when downlink resource is saturated. We conclude that the energy of MHs can be conserved further by applying EPSS when the traffic load is saturated. The effect of energy saving becomes more obvious when the portion of NRT-VBR and BE services is greater than that of RT-VBR and GBR services.

  1. Enhancing the conservation of crop wild relatives in England.

    Science.gov (United States)

    Fielder, Hannah; Brotherton, Peter; Hosking, Julian; Hopkins, John J; Ford-Lloyd, Brian; Maxted, Nigel

    2015-01-01

    Humans require resilient, rapidly renewable and sustainable supplies of food and many other plant-derived supplies. However, the combined effects of climate change and population growth compromise the provision of these supplies particularly in respect to global food security. Crop wild relatives (CWR) contain higher genetic diversity than crops and harbour traits that can improve crop resilience and yield through plant breeding. However, in common with most countries, CWR are poorly conserved in England. There is currently no provision for long-term CWR conservation in situ, and comprehensive ex situ collection and storage of CWR is also lacking. However, there is a commitment to achieve their conservation in England's Biodiversity Strategy and the UK has international commitments to do so as part of the Global Plant Conservation Strategy. Here, we identify a series of measures that could enhance the conservation of English CWR, thereby supporting the achievement of these national and international objectives. We provide an inventory of 148 priority English CWR, highlight hotspots of CWR diversity in sites including The Lizard Peninsula, the Dorset coast and Cambridgeshire and suggest appropriate sites for the establishment of a complementary network of genetic reserves. We also identify individual in situ and ex situ priorities for each English CWR. Based on these analyses, we make recommendations whose implementation could provide effective, long-term conservation of English CWR whilst facilitating their use in crop improvement.

  2. Relative efforts of countries to conserve world’s megafauna

    Directory of Open Access Journals (Sweden)

    Peter A. Lindsey

    2017-04-01

    Full Text Available Surprisingly little attention has been paid to variation among countries in contributions to conservation. As a first step, we developed a Megafauna Conservation Index (MCI that assesses the spatial, ecological and financial contributions of 152 nations towards conservation of the world’s terrestrial megafauna. We chose megafauna because they are particularly valuable in economic, ecological and societal terms, and are challenging and expensive to conserve. We categorised these 152 countries as being above- or below-average performers based on whether their contribution to megafauna conservation was higher or lower than the global mean; ‘major’ performers or underperformers were those whose contribution exceeded 1 SD over or under the mean, respectively. Ninety percent of countries in North/Central America and 70% of countries in Africa were classified as major or above-average performers, while approximately one-quarter of countries in Asia (25% and Europe (21% were identified as major underperformers. We present our index to emphasise the need for measuring conservation performance, to help nations identify how best they could improve their efforts, and to present a starting point for the development of more robust and inclusive measures (noting how the IUCN Red List evolved over time. Our analysis points to three approaches that countries could adopt to improve their contribution to global megafauna conservation, depending on their circumstances: (1 upgrading or expanding their domestic protected area networks, with a particular emphasis on conserving large carnivore and herbivore habitat, (2 increase funding for conservation at home or abroad, or (3 ‘rewilding’ their landscapes. Once revised and perfected, we recommend publishing regular conservation rankings in the popular media to recognise major-performers, foster healthy pride and competition among nations, and identify ways for governments to improve their performance.

  3. Human developmental enhancers conserved between deuterostomes and protostomes.

    Directory of Open Access Journals (Sweden)

    Shoa L Clarke

    Full Text Available The identification of homologies, whether morphological, molecular, or genetic, is fundamental to our understanding of common biological principles. Homologies bridging the great divide between deuterostomes and protostomes have served as the basis for current models of animal evolution and development. It is now appreciated that these two clades share a common developmental toolkit consisting of conserved transcription factors and signaling pathways. These patterning genes sometimes show common expression patterns and genetic interactions, suggesting the existence of similar or even conserved regulatory apparatus. However, previous studies have found no regulatory sequence conserved between deuterostomes and protostomes. Here we describe the first such enhancers, which we call bilaterian conserved regulatory elements (Bicores. Bicores show conservation of sequence and gene synteny. Sequence conservation of Bicores reflects conserved patterns of transcription factor binding sites. We predict that Bicores act as response elements to signaling pathways, and we show that Bicores are developmental enhancers that drive expression of transcriptional repressors in the vertebrate central nervous system. Although the small number of identified Bicores suggests extensive rewiring of cis-regulation between the protostome and deuterostome clades, additional Bicores may be revealed as our understanding of cis-regulatory logic and sample of bilaterian genomes continue to grow.

  4. Relativistic dynamics without conservation laws

    OpenAIRE

    Rothenstein, Bernhard; Popescu, Stefan

    2006-01-01

    We show that relativistic dynamics can be approached without using conservation laws (conservation of momentum, of energy and of the centre of mass). Our approach avoids collisions that are not easy to teach without mnemonic aids. The derivations are based on the principle of relativity and on its direct consequence, the addition law of relativistic velocities.

  5. Designing Conservation Corridors in Production Landscapes: Assessment Methods, Implementation Issues, and Lessons Learned

    Directory of Open Access Journals (Sweden)

    Amanda T. Lombard

    2010-09-01

    Full Text Available Designing broad-scale conservation corridors has become increasingly common as a way of conducting an assessment for achieving targets for the representation and persistence of nature. However, since many of these corridors must traverse agricultural and other production landscapes, planning and implementation are not trivial tasks. Most approaches to conservation assessments in the dynamic world of production landscapes are data-intensive and analytically complex. However, in the real world, donor and other external requirements impose time and budget constraints, and dictate strong stakeholder involvement in the entire planning process. In order to accommodate this, assessments must be rapid, cheap, and the approach and products must be comprehensible and acceptable to stakeholders. Here we describe such an assessment aimed at identifying and implementing a network of conservation corridors in the Gouritz Initiative project domain of South Africa's Cape Floristic Region hotspot. We used empirical data and expert knowledge to identify a corridor network hypothesized to sustain key ecological and evolutionary processes. We also consulted experts to provide a spatially explicit assessment of the opportunity costs of conservation associated with agriculture, the predominant land use in the region. We used these products to identify categories of land requiring different actions and instruments to achieve conservation goals, thereby moving from the "where" to the "how" of conservation. This information was then fed into the collaborative strategy development process for the Gouritz Initiative. Our discussion emphasizes the lessons that we learnt from undertaking this assessment, particularly lessons regarding the implementation of the planning products. We conclude that at the outset of any planning project, a consensus on the vision must be achieved, a detailed social assessment of appropriate institutions must be undertaken, and a learning

  6. A COMPARISON OF TAXONOMIC DISTINCTNESS VERSUS RICHNESS AS CRITERIA FOR SETTING CONSERVATION PRIORITIES FOR NORTH AMERICAN BIRDS. (R825311)

    Science.gov (United States)

    AbstractIn choosing sites for a conservation reserve network, representation of the greatest number of species in the sites selected is a common objective. This approach implicitly assumes that all species have equal conservation value. An alternative objective is to ...

  7. Mapping the temporary and perennial character of whole river networks

    Science.gov (United States)

    González-Ferreras, A. M.; Barquín, J.

    2017-08-01

    Knowledge of the spatial distribution of temporary and perennial river channels in a whole catchment is important for effective integrated basin management and river biodiversity conservation. However, this information is usually not available or is incomplete. In this study, we present a statistically based methodology to classify river segments from a whole river network (Deva-Cares catchment, Northern Spain) as temporary or perennial. This method is based on an a priori classification of a subset of river segments as temporary or perennial, using field surveys and aerial images, and then running Random Forest models to predict classification membership for the rest of the river network. The independent variables and the river network were derived following a computer-based geospatial simulation of riverine landscapes. The model results show high values of overall accuracy, sensitivity, and specificity for the evaluation of the fitted model to the training and testing data set (≥0.9). The most important independent variables were catchment area, area occupied by broadleaf forest, minimum monthly precipitation in August, and average catchment elevation. The final map shows 7525 temporary river segments (1012.5 km) and 3731 perennial river segments (662.5 km). A subsequent validation of the mapping results using River Habitat Survey data and expert knowledge supported the validity of the proposed maps. We conclude that the proposed methodology is a valid method for mapping the limits of flow permanence that could substantially increase our understanding of the spatial links between terrestrial and aquatic interfaces, improving the research, management, and conservation of river biodiversity and functioning.

  8. Extinction risks and the conservation of Madagascar's reptiles.

    Directory of Open Access Journals (Sweden)

    Richard K B Jenkins

    Full Text Available BACKGROUND: An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. METHODOLOGY/PRINCIPAL FINDINGS: Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. CONCLUSIONS/SIGNIFICANCE: With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in

  9. Extinction risks and the conservation of Madagascar's reptiles.

    Science.gov (United States)

    Jenkins, Richard K B; Tognelli, Marcelo F; Bowles, Philip; Cox, Neil; Brown, Jason L; Chan, Lauren; Andreone, Franco; Andriamazava, Alain; Andriantsimanarilafy, Raphali R; Anjeriniaina, Mirana; Bora, Parfait; Brady, Lee D; Hantalalaina, Elisoa F; Glaw, Frank; Griffiths, Richard A; Hilton-Taylor, Craig; Hoffmann, Michael; Katariya, Vineet; Rabibisoa, Nirhy H; Rafanomezantsoa, Jeannot; Rakotomalala, Domoina; Rakotondravony, Hery; Rakotondrazafy, Ny A; Ralambonirainy, Johans; Ramanamanjato, Jean-Baptiste; Randriamahazo, Herilala; Randrianantoandro, J Christian; Randrianasolo, Harison H; Randrianirina, Jasmin E; Randrianizahana, Hiarinirina; Raselimanana, Achille P; Rasolohery, Andriambolantsoa; Ratsoavina, Fanomezana M; Raxworthy, Christopher J; Robsomanitrandrasana, Eric; Rollande, Finoana; van Dijk, Peter P; Yoder, Anne D; Vences, Miguel

    2014-01-01

    An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of

  10. Extinction Risks and the Conservation of Madagascar's Reptiles

    Science.gov (United States)

    Jenkins, Richard K. B.; Tognelli, Marcelo F.; Bowles, Philip; Cox, Neil; Brown, Jason L.; Chan, Lauren; Andreone, Franco; Andriamazava, Alain; Andriantsimanarilafy, Raphali R.; Anjeriniaina, Mirana; Bora, Parfait; Brady, Lee D.; Hantalalaina, Elisoa F.; Glaw, Frank; Griffiths, Richard A.; Hilton-Taylor, Craig; Hoffmann, Michael; Katariya, Vineet; Rabibisoa, Nirhy H.; Rafanomezantsoa, Jeannot; Rakotomalala, Domoina; Rakotondravony, Hery; Rakotondrazafy, Ny A.; Ralambonirainy, Johans; Ramanamanjato, Jean-Baptiste; Randriamahazo, Herilala; Randrianantoandro, J. Christian; Randrianasolo, Harison H.; Randrianirina, Jasmin E.; Randrianizahana, Hiarinirina; Raselimanana, Achille P.; Rasolohery, Andriambolantsoa; Ratsoavina, Fanomezana M.; Raxworthy, Christopher J.; Robsomanitrandrasana, Eric; Rollande, Finoana; van Dijk, Peter P.; Yoder, Anne D.; Vences, Miguel

    2014-01-01

    Background An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Methodology/Principal Findings Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. Conclusions/Significance With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and

  11. Emotion shapes the diffusion of moralized content in social networks.

    Science.gov (United States)

    Brady, William J; Wills, Julian A; Jost, John T; Tucker, Joshua A; Van Bavel, Jay J

    2017-07-11

    Political debate concerning moralized issues is increasingly common in online social networks. However, moral psychology has yet to incorporate the study of social networks to investigate processes by which some moral ideas spread more rapidly or broadly than others. Here, we show that the expression of moral emotion is key for the spread of moral and political ideas in online social networks, a process we call "moral contagion." Using a large sample of social media communications about three polarizing moral/political issues ( n = 563,312), we observed that the presence of moral-emotional words in messages increased their diffusion by a factor of 20% for each additional word. Furthermore, we found that moral contagion was bounded by group membership; moral-emotional language increased diffusion more strongly within liberal and conservative networks, and less between them. Our results highlight the importance of emotion in the social transmission of moral ideas and also demonstrate the utility of social network methods for studying morality. These findings offer insights into how people are exposed to moral and political ideas through social networks, thus expanding models of social influence and group polarization as people become increasingly immersed in social media networks.

  12. The value of flexibility in conservation financing.

    Science.gov (United States)

    Lennox, Gareth D; Fargione, Joseph; Spector, Sacha; Williams, Gwyn; Armsworth, Paul R

    2017-06-01

    Land-acquisition strategies employed by conservation organizations vary in their flexibility. Conservation-planning theory largely fails to reflect this by presenting models that are either extremely inflexible-parcel acquisitions are irreversible and budgets are fixed-or extremely flexible-previously acquired parcels can readily be sold. This latter approach, the selling of protected areas, is infeasible or problematic in many situations. We considered the value to conservation organizations of increasing the flexibility of their land-acquisition strategies through their approach to financing deals. Specifically, we modeled 2 acquisition-financing methods commonly used by conservation organizations: borrowing and budget carry-over. Using simulated data, we compared results from these models with those from an inflexible fixed-budget model and an extremely flexible selling model in which previous acquisitions could be sold to fund new acquisitions. We then examined 3 case studies of how conservation organizations use borrowing and budget carry-over in practice. Model comparisons showed that borrowing and budget carry-over always returned considerably higher rewards than the fixed-budget model. How they performed relative to the selling model depended on the relative conservation value of past acquisitions. Both the models and case studies showed that incorporating flexibility through borrowing or budget carry-over gives conservation organizations the ability to purchase parcels of higher conservation value than when budgets are fixed without the problems associated with the selling of protected areas. © 2016 Society for Conservation Biology.

  13. Pan-European strategy for genetic conservation of forest trees and establishment of a core network of dynamic conservation units

    NARCIS (Netherlands)

    Vries, de S.M.G.; Alan, Murat; Bozzano, Michele; Burianek, Vaclav

    2015-01-01

    The diversity of forests, at the level of species and at the level of genetic diversity within species, is an important resource for Europe. Over the past several decades European countries have made considerable efforts to conserve the genetic diversity of tree species. According to the EUFGIS

  14. The International Trade Network: weighted network analysis and modelling

    International Nuclear Information System (INIS)

    Bhattacharya, K; Mukherjee, G; Manna, S S; Saramäki, J; Kaski, K

    2008-01-01

    Tools of the theory of critical phenomena, namely the scaling analysis and universality, are argued to be applicable to large complex web-like network structures. Using a detailed analysis of the real data of the International Trade Network we argue that the scaled link weight distribution has an approximate log-normal distribution which remains robust over a period of 53 years. Another universal feature is observed in the power-law growth of the trade strength with gross domestic product, the exponent being similar for all countries. Using the 'rich-club' coefficient measure of the weighted networks it has been shown that the size of the rich-club controlling half of the world's trade is actually shrinking. While the gravity law is known to describe well the social interactions in the static networks of population migration, international trade, etc, here for the first time we studied a non-conservative dynamical model based on the gravity law which excellently reproduced many empirical features of the ITN

  15. Compromises Between Quality of Service Metrics and Energy Consumption of Hierarchical and Flat Routing Protocols for Wireless Sensors Network

    Directory of Open Access Journals (Sweden)

    Abdelbari BEN YAGOUTA

    2016-11-01

    Full Text Available Wireless Sensor Network (WSN is wireless network composed of spatially distributed and tiny autonomous nodes, which cooperatively monitor physical or environmental conditions. Among the concerns of these networks is prolonging the lifetime by saving nodes energy. There are several protocols specially designed for WSNs based on energy conservation. However, many WSNs applications require QoS (Quality of Service criteria, such as latency, reliability and throughput. In this paper, we will compare three routing protocols for wireless sensors network LEACH (Low Energy Adaptive Clustering Hierarchy, AODV (Ad hoc on demand Distance Vector and LABILE (Link Quality-Based Lexical Routing using Castalia simulator in terms of energy consumption, throughput, reliability and latency time of packets received by sink under different conditions to determinate the best configurations that offers the most suitable compromises between energy conservation and all QoS metrics for each routing protocols. The results show that, the best configurations that offer the suitable compromises between energy conservation and all QoS metrics is a large number of deployed nodes with low packet rate for LEACH (300 nodes and 1 packet/s, a medium number of deployed nodes with low packet rate For AODV (100 nodes and 1 packet/s and a very low nodes density with low packet rate for LABILE (50 nodes and 1 packet/s.

  16. Prioritizing Urban Habitats for Connectivity Conservation: Integrating Centrality and Ecological Metrics.

    Science.gov (United States)

    Poodat, Fatemeh; Arrowsmith, Colin; Fraser, David; Gordon, Ascelin

    2015-09-01

    Connectivity among fragmented areas of habitat has long been acknowledged as important for the viability of biological conservation, especially within highly modified landscapes. Identifying important habitat patches in ecological connectivity is a priority for many conservation strategies, and the application of 'graph theory' has been shown to provide useful information on connectivity. Despite the large number of metrics for connectivity derived from graph theory, only a small number have been compared in terms of the importance they assign to nodes in a network. This paper presents a study that aims to define a new set of metrics and compares these with traditional graph-based metrics, used in the prioritization of habitat patches for ecological connectivity. The metrics measured consist of "topological" metrics, "ecological metrics," and "integrated metrics," Integrated metrics are a combination of topological and ecological metrics. Eight metrics were applied to the habitat network for the fat-tailed dunnart within Greater Melbourne, Australia. A non-directional network was developed in which nodes were linked to adjacent nodes. These links were then weighted by the effective distance between patches. By applying each of the eight metrics for the study network, nodes were ranked according to their contribution to the overall network connectivity. The structured comparison revealed the similarity and differences in the way the habitat for the fat-tailed dunnart was ranked based on different classes of metrics. Due to the differences in the way the metrics operate, a suitable metric should be chosen that best meets the objectives established by the decision maker.

  17. Hydrogen bond networks determine emergent mechanical and thermodynamic properties across a protein family

    Directory of Open Access Journals (Sweden)

    Dallakyan Sargis

    2008-08-01

    Full Text Available Abstract Background Gram-negative bacteria use periplasmic-binding proteins (bPBP to transport nutrients through the periplasm. Despite immense diversity within the recognized substrates, all members of the family share a common fold that includes two domains that are separated by a conserved hinge. The hinge allows the protein to cycle between open (apo and closed (ligated conformations. Conformational changes within the proteins depend on a complex interplay of mechanical and thermodynamic response, which is manifested as an increase in thermal stability and decrease of flexibility upon ligand binding. Results We use a distance constraint model (DCM to quantify the give and take between thermodynamic stability and mechanical flexibility across the bPBP family. Quantitative stability/flexibility relationships (QSFR are readily evaluated because the DCM links mechanical and thermodynamic properties. We have previously demonstrated that QSFR is moderately conserved across a mesophilic/thermophilic RNase H pair, whereas the observed variance indicated that different enthalpy-entropy mechanisms allow similar mechanical response at their respective melting temperatures. Our predictions of heat capacity and free energy show marked diversity across the bPBP family. While backbone flexibility metrics are mostly conserved, cooperativity correlation (long-range couplings also demonstrate considerable amount of variation. Upon ligand removal, heat capacity, melting point, and mechanical rigidity are, as expected, lowered. Nevertheless, significant differences are found in molecular cooperativity correlations that can be explained by the detailed nature of the hydrogen bond network. Conclusion Non-trivial mechanical and thermodynamic variation across the family is explained by differences within the underlying H-bond networks. The mechanism is simple; variation within the H-bond networks result in altered mechanical linkage properties that directly affect

  18. Tourism revenue as a conservation tool for threatened birds in protected areas.

    Directory of Open Access Journals (Sweden)

    Rochelle Steven

    Full Text Available Many bird populations worldwide are at risk of extinction, and rely heavily on protected area networks for their continued conservation. Tourism to these areas contributes to conservation by generating revenue for management. Here we quantify the contribution of tourism revenue for bird species in the IUCN Red List, using a simple accounting method. Relevant data are available for 90 (16% of the 562 critically endangered and endangered species. Contributions of tourism to bird conservation are highest, 10-64%, in South America, Africa, and their neighbouring islands. Critically endangered bird species rely on tourism more heavily than endangered species (p<0.02. Many protected areas could also enhance their management budgets by promoting birdwatching tourism specifically.

  19. Tourism Revenue as a Conservation Tool for Threatened Birds in Protected Areas

    Science.gov (United States)

    Steven, Rochelle; Castley, J. Guy; Buckley, Ralf

    2013-01-01

    Many bird populations worldwide are at risk of extinction, and rely heavily on protected area networks for their continued conservation. Tourism to these areas contributes to conservation by generating revenue for management. Here we quantify the contribution of tourism revenue for bird species in the IUCN Red List, using a simple accounting method. Relevant data are available for 90 (16%) of the 562 critically endangered and endangered species. Contributions of tourism to bird conservation are highest, 10–64%, in South America, Africa, and their neighbouring islands. Critically endangered bird species rely on tourism more heavily than endangered species (p<0.02). Many protected areas could also enhance their management budgets by promoting birdwatching tourism specifically. PMID:23667498

  20. A Dense Small-Scale Seismic Network in the Ngorongoro Conservation Area (Northern Tanzania)

    Science.gov (United States)

    Parisi, L.; Lombardo, L.; Rodriguez-Mustafa, M.; Mai, P. M.

    2017-12-01

    A temporary deployment consisting of sixteen broadband seismic stations is conducted for the first time in the Ngorongoro Conservation Area (NCA, Northern Tanzania), located at the boundary between the Tanzanian Craton and East African Rift. A deep knowledge of the faulting systems and tectonics of the area is needed to better understand the contribution of the synsedimentary faults to the deposition of the Olduvai and surrounding basins affecting the landscapes of the Homo Habilis first settlements. Complex fault systems have been mapped in the field but their connection, especially at depth, is not well known. A first batch of ten instruments was installed in June 2016. In June 2017 two stations were dismissed and a second batch of six stations was installed in new locations. The current network of fourteen stations will record until May 2018. Stations are equipped with Nanometrics Trillium Compact Posthole 120 s sensor and Centaur digitiser recording continuously at 200 Hz. The whole network covers 1400 km2 and station interspace ranges from 8 to 15 km. We analyse probabilistic power spectra densities of the seismic noise to obtain insights of its origin and test the performances of the stations. Although factories do not exist in the area and most of the stations are far from roads, ambient noise in the range 0.01 - 1 s is relatively high (between -120 dB and -100dB at 0.1 s) probably because of the abundance of livestock living in the NCA. Ambient noise in the period range 1 - 10 s (secondary microseisms) decreases from east to west. Although the main source of the microseisms is located in the Indian Ocean (east of the study area), a contribution from the low period tremors coming from the nearby active volcano Ol Doinyo Lengai (north-east of the study area) is expected. Whereas the longer period noise (10 - 100 s) is very low in the vertical component seismograms, it is higher than the high noise model in the horizontal components for most of the stations

  1. Meta-analysis of inter-species liver co-expression networks elucidates traits associated with common human diseases.

    Directory of Open Access Journals (Sweden)

    Kai Wang

    2009-12-01

    Full Text Available Co-expression networks are routinely used to study human diseases like obesity and diabetes. Systematic comparison of these networks between species has the potential to elucidate common mechanisms that are conserved between human and rodent species, as well as those that are species-specific characterizing evolutionary plasticity. We developed a semi-parametric meta-analysis approach for combining gene-gene co-expression relationships across expression profile datasets from multiple species. The simulation results showed that the semi-parametric method is robust against noise. When applied to human, mouse, and rat liver co-expression networks, our method out-performed existing methods in identifying gene pairs with coherent biological functions. We identified a network conserved across species that highlighted cell-cell signaling, cell-adhesion and sterol biosynthesis as main biological processes represented in genome-wide association study candidate gene sets for blood lipid levels. We further developed a heterogeneity statistic to test for network differences among multiple datasets, and demonstrated that genes with species-specific interactions tend to be under positive selection throughout evolution. Finally, we identified a human-specific sub-network regulated by RXRG, which has been validated to play a different role in hyperlipidemia and Type 2 diabetes between human and mouse. Taken together, our approach represents a novel step forward in integrating gene co-expression networks from multiple large scale datasets to leverage not only common information but also differences that are dataset-specific.

  2. Effects of Conventional and Conservation Tillage on Soil Hydraulic Properties of a Silty-loamy Soil

    DEFF Research Database (Denmark)

    Wahl, Niels Arne; Bens, O.; Buczko, U.

    2004-01-01

    Infiltration into soils is strongly correlated with macroporosity. Under agricultural land use, the properties of the macropore network are governed by the applied management and tillage system. On an experimental site with a silt loam soil partly under conventional and conservation tillage, the ......, conservation tillage could possibly offer a means to reduce surface runoff and flood generation in agricultural landscapes dominated by silty-loamy soils. d 2...

  3. Where and how to manage: Optimal selection of conservation actions for multiple species.

    Directory of Open Access Journals (Sweden)

    Astrid van Teeffelen

    2008-01-01

    Full Text Available Multiple alternative options are frequently available for the protection, maintenance or restoration of conservation areas. The choice of a particular management action can have large effects on the species occurring in the area, because different actions have different effects on different species. Together with the fact that conservation funds are limited and particular management actions are costly, it would be desirable to be able to identify where, and what kind of management should be applied to maximize conservation benefits. Currently available site-selection algorithms can identify the optimal set of sites for a reserve network. However, these algorithms have not been designed to answer what kind of action would be most beneficial at these sites when multiple alternative actions are available. We describe an algorithm capable of solving multi-species planning problems with multiple management options per site. The algorithm is based on benefit functions, which translate the effect of a management action on species representation levels into a value, in order to identify the most beneficial option. We test the performance of this algorithm with simulated data for different types of benefit functions and show that the algorithm’s solutions are optimal, or very near globally optimal, partially depending on the type of benefit function used. The good performance of the proposed algorithm suggests that it could be profitably used for large multi-action multi-species conservation planning problems.

  4. Ten ways remote sensing can contribute to conservation.

    Science.gov (United States)

    Rose, Robert A; Byler, Dirck; Eastman, J Ron; Fleishman, Erica; Geller, Gary; Goetz, Scott; Guild, Liane; Hamilton, Healy; Hansen, Matt; Headley, Rachel; Hewson, Jennifer; Horning, Ned; Kaplin, Beth A; Laporte, Nadine; Leidner, Allison; Leimgruber, Peter; Morisette, Jeffrey; Musinsky, John; Pintea, Lilian; Prados, Ana; Radeloff, Volker C; Rowen, Mary; Saatchi, Sassan; Schill, Steve; Tabor, Karyn; Turner, Woody; Vodacek, Anthony; Vogelmann, James; Wegmann, Martin; Wilkie, David; Wilson, Cara

    2015-04-01

    In an effort to increase conservation effectiveness through the use of Earth observation technologies, a group of remote sensing scientists affiliated with government and academic institutions and conservation organizations identified 10 questions in conservation for which the potential to be answered would be greatly increased by use of remotely sensed data and analyses of those data. Our goals were to increase conservation practitioners' use of remote sensing to support their work, increase collaboration between the conservation science and remote sensing communities, identify and develop new and innovative uses of remote sensing for advancing conservation science, provide guidance to space agencies on how future satellite missions can support conservation science, and generate support from the public and private sector in the use of remote sensing data to address the 10 conservation questions. We identified a broad initial list of questions on the basis of an email chain-referral survey. We then used a workshop-based iterative and collaborative approach to whittle the list down to these final questions (which represent 10 major themes in conservation): How can global Earth observation data be used to model species distributions and abundances? How can remote sensing improve the understanding of animal movements? How can remotely sensed ecosystem variables be used to understand, monitor, and predict ecosystem response and resilience to multiple stressors? How can remote sensing be used to monitor the effects of climate on ecosystems? How can near real-time ecosystem monitoring catalyze threat reduction, governance and regulation compliance, and resource management decisions? How can remote sensing inform configuration of protected area networks at spatial extents relevant to populations of target species and ecosystem services? How can remote sensing-derived products be used to value and monitor changes in ecosystem services? How can remote sensing be used to

  5. PipY, a Member of the Conserved COG0325 Family of PLP-Binding Proteins, Expands the Cyanobacterial Nitrogen Regulatory Network

    Directory of Open Access Journals (Sweden)

    José I. Labella

    2017-07-01

    Full Text Available Synechococcus elongatus PCC 7942 is a paradigmatic model organism for nitrogen regulation in cyanobacteria. Expression of genes involved in nitrogen assimilation is positively regulated by the 2-oxoglutarate receptor and global transcriptional regulator NtcA. Maximal activation requires the subsequent binding of the co-activator PipX. PII, a protein found in all three domains of life as an integrator of signals of the nitrogen and carbon balance, binds to PipX to counteract NtcA activity at low 2-oxoglutarate levels. PII-PipX complexes can also bind to the transcriptional regulator PlmA, whose regulon remains unknown. Here we expand the nitrogen regulatory network to PipY, encoded by the bicistronic operon pipXY in S. elongatus. Work with PipY, the cyanobacterial member of the widespread family of COG0325 proteins, confirms the conserved roles in vitamin B6 and amino/keto acid homeostasis and reveals new PLP-related phenotypes, including sensitivity to antibiotics targeting essential PLP-holoenzymes or synthetic lethality with cysK. In addition, the related phenotypes of pipY and pipX mutants are consistent with genetic interactions in the contexts of survival to PLP-targeting antibiotics and transcriptional regulation. We also showed that PipY overexpression increased the length of S. elongatus cells. Taken together, our results support a universal regulatory role for COG0325 proteins, paving the way to a better understanding of these proteins and of their connections with other biological processes.

  6. Mass, matter, materialization, mattergenesis and conservation of charge

    International Nuclear Information System (INIS)

    Tsan, Ung Chan

    2013-01-01

    Conservation of mass in classical physics and in chemistry is considered to be equivalent to conservation of matter and is a necessary condition together with other universal conservation laws to account for observed experiments. Indeed matter conservation is associated to conservation of building blocks (molecules, atoms, nucleons, quarks and leptons). Matter is massive but mass and matter are two distinct concepts even if conservation of mass and conservation of matter represent the same reality in classical physics and chemistry. Conservation of mass is a consequence of conservation of atoms. Conservation of mass is valid because in these cases it is a very good approximation, the variation of mass being tiny and undetectable by weighing. However, nuclear physics and particle physics clearly show that conservation of mass is not valid to express conservation of matter. Mass is one form of energy, is a positive quantity and plays a fundamental role in dynamics allowing particles to be accelerated. Origin of mass may be linked to recently discovered Higgs bosons. Matter conservation means conservation of baryonic number A and leptonic number L, A and L being algebraic numbers. Positive A and L are associated to matter particles, negative A and L are associated to antimatter particles. All known interactions do conserve matter thus could not generate, from pure energy, a number of matter particles different from that of number of antimatter particles. But our universe is material and neutral, this double message has to be deciphered simultaneously. Asymmetry of our universe demands an interaction which violates matter conservation but obeys all universal conservation laws, in particular conservation of electric charge Q. Expression of Q shows that conservation of (A–L) and total flavor TF are necessary and sufficient to conserve Q. Conservation of A and L is indeed a trivial case of conservation of (A–L) and is valid for all known interactions of the standard

  7. Building on Two Decades of Ecosystem Management and Biodiversity Conservation under the Northwest Forest Plan, USA

    Directory of Open Access Journals (Sweden)

    Dominick A. DellaSala

    2015-09-01

    Full Text Available The 1994 Northwest Forest Plan (NWFP shifted federal lands management from a focus on timber production to ecosystem management and biodiversity conservation. The plan established a network of conservation reserves and an ecosystem management strategy on ~10 million hectares from northern California to Washington State, USA, within the range of the federally threatened northern spotted owl (Strix occidentalis caurina. Several subsequent assessments—and 20 years of data from monitoring programs established under the plan—have demonstrated the effectiveness of this reserve network and ecosystem management approach in making progress toward attaining many of the plan’s conservation and ecosystem management goals. This paper (1 showcases the fundamental conservation biology and ecosystem management principles underpinning the NWFP as a case study for managers interested in large-landscape conservation; and (2 recommends improvements to the plan’s strategy in response to unprecedented climate change and land-use threats. Twenty years into plan implementation, however, the U.S. Forest Service and Bureau of Land Management, under pressure for increased timber harvest, are retreating from conservation measures. We believe that federal agencies should instead build on the NWFP to ensure continuing success in the Pacific Northwest. We urge federal land managers to (1 protect all remaining late-successional/old-growth forests; (2 identify climate refugia for at-risk species; (3 maintain or increase stream buffers and landscape connectivity; (4 decommission and repair failing roads to improve water quality; (5 reduce fire risk in fire-prone tree plantations; and (6 prevent logging after fires in areas of high conservation value. In many respects, the NWFP is instructive for managers considering similar large-scale conservation efforts.

  8. Utilizing social media for informal ocean conservation and education: The BioOceanography Project

    Science.gov (United States)

    Payette, J.

    2016-02-01

    Science communication through the use of social media is a rapidly evolving and growing pursuit in academic and scientific circles. Online tools and social media are being used in not only scientific communication but also scientific publication, education, and outreach. Standards and usage of social media as well as other online tools for communication, networking, outreach, and publication are always in development. Caution and a conservative attitude towards these novel "Science 2.0" tools is understandable because of their rapidly changing nature and the lack of professional standards for using them. However there are some key benefits and unique ways social media, online systems, and other Open or Open Source technologies, software, and "Science 2.0" tools can be utilized for academic purposes such as education and outreach. Diverse efforts for ocean conservation and education will continue to utilize social media for a variety of purposes. The BioOceanography project is an informal communication, education, outreach, and conservation initiative created for enhancing knowledge related to Oceanography and Marine Science with an unbiased yet conservation-minded approach and in an Open Source format. The BioOceanography project is ongoing and still evolving, but has already contributed to ocean education and conservation communication in key ways through a concerted web presence since 2013, including a curated Twitter account @_Oceanography and BioOceanography blog style website. Social media tools like those used in this project, if used properly can be highly effective and valuable for encouraging students, networking with researchers, and educating the general public in Oceanography.

  9. Enhancing the conservation of crop wild relatives in England.

    Directory of Open Access Journals (Sweden)

    Hannah Fielder

    Full Text Available Humans require resilient, rapidly renewable and sustainable supplies of food and many other plant-derived supplies. However, the combined effects of climate change and population growth compromise the provision of these supplies particularly in respect to global food security. Crop wild relatives (CWR contain higher genetic diversity than crops and harbour traits that can improve crop resilience and yield through plant breeding. However, in common with most countries, CWR are poorly conserved in England. There is currently no provision for long-term CWR conservation in situ, and comprehensive ex situ collection and storage of CWR is also lacking. However, there is a commitment to achieve their conservation in England's Biodiversity Strategy and the UK has international commitments to do so as part of the Global Plant Conservation Strategy. Here, we identify a series of measures that could enhance the conservation of English CWR, thereby supporting the achievement of these national and international objectives. We provide an inventory of 148 priority English CWR, highlight hotspots of CWR diversity in sites including The Lizard Peninsula, the Dorset coast and Cambridgeshire and suggest appropriate sites for the establishment of a complementary network of genetic reserves. We also identify individual in situ and ex situ priorities for each English CWR. Based on these analyses, we make recommendations whose implementation could provide effective, long-term conservation of English CWR whilst facilitating their use in crop improvement.

  10. Regional effects of agricultural conservation practices on nutrient transport

    Science.gov (United States)

    Anna Maria Garcia; Richard B. Alexander; Jeffrey G. Arnold; Lee Norfleet; Mike White; Dale M. Robertson; Gregory Schwarz

    2016-01-01

    The Conservation Effects Assessment Program (CEAP), initiated by USDA Natural Resources Conservation Service (NRCS), has the goal of quantifying the environmental benefits of agricultural conservation practices. As part of this effort, detailed farmer surveyswere compiled to document the adoption of conservation practices. Survey data showed that up to 38...

  11. Bird community conservation and carbon offsets in western North America.

    Science.gov (United States)

    Schuster, Richard; Martin, Tara G; Arcese, Peter

    2014-01-01

    Conservation initiatives to protect and restore valued species and communities in human-dominated landscapes face huge challenges linked to the cost of acquiring habitat. We ask how the sale of forest carbon offsets could reduce land acquisition costs, and how the alternate goals of maximizing α or β-diversity in focal communities could affect the prioritization land parcels over a range of conservation targets. Maximizing total carbon storage and carbon sequestration potential reduced land acquisition costs by up to 48%. Maximizing β rather than α-diversity within forest and savannah bird communities reduced acquisition costs by up to 15%, and when these solutions included potential carbon credit revenues, acquisition cost reductions up to 32% were achieved. However, the total cost of conservation networks increased exponentially as area targets increased in all scenarios. Our results indicate that carbon credit sales have the potential to enhance conservation outcomes in human-dominated landscapes by reducing the net acquisition costs of land conservation in old and maturing forests essential for the persistence of old forest plant and animal communities. Maximizing β versus α-diversity may further reduce costs by reducing the total area required to meet conservation targets and enhancing landscape heterogeneity. Although the potential value of carbon credit sales declined as a fraction of total acquisition costs, even conservative scenarios using a carbon credit value of $12.5/T suggest reductions in acquisition cost of up to $235 M, indicating that carbon credit sales could substantially reduce the costs of conservation.

  12. Energy and round time estimation method for mobile wireless sensor networks

    International Nuclear Information System (INIS)

    Ismat, M.; Qureshi, R.; Imam, M.U.

    2018-01-01

    Clustered WSN (Wireless Sensor Networks) is a hierarchical network structure that conserves energy by distributing the task of sensing and data transfer to destination among the non-CH (Cluster-Head) and CH (Cluster Head) node in a cluster. In clustered MWSN (Mobile Wireless Sensor Network), cluster maintenance to increase at a reception at the destination during communication operation is difficult due to the movement of CHs and non-CH nodes in and out of the cluster. To conserve energy and increased data transfer to the destination, it is necessary to find the duration after which sensor node’s role should be changed from CH to non-CH and vice-versa. In this paper, we have proposed an energy independent round time scheme to identify the duration after which re-clustering procedure should be invoked for changing roles of sensor nodes as CHs and associated nodes to conserve energy and increased data delivery. This depends on the dissemination interval of the sensor nodes rather than sensor node’s energy. We have also provided a complete analytical estimate of network energy consumption with energy consumed in every phase of a around. (author)

  13. To what extent do potential conservation donors value community-aspects of conservation projects in low income countries?

    Science.gov (United States)

    Young, Richard P.; Gibbons, James M.; Jones, Julia P. G.

    2018-01-01

    There is a major gap in funding required for conservation, especially in low income countries. Given the significant contribution of taxpayers in industrialized countries to funding conservation overseas, and donations from membership organisation, understanding the preferences of ordinary people in a high income country for different attributes of conservation projects is valuable for future marketing of conservation. We conducted a discrete choice experiment with visitors to a UK zoo, while simultaneously conducting a revealed preference study through a real donation campaign on the same sample. Respondents showed the highest willingness to pay for projects that have local community involvement in management (95% confidence interval £9.82 to £15.83), and for improvement in threatened species populations (£2.97 - £13.87). Both of these were significantly larger than the willingness to pay for projects involving provision of alternative livelihoods, or improving the condition of conservation sites. Results of the simultaneous donation campaign showed that respondents were very willing to donate the suggested £1 or above donation (88% made a donation, n = 1798); there was no effect of which of the two campaigns they were exposed to (threatened species management or community involvement in management). The small number of people who did not make a donation had a higher stated willingness to pay within the choice experiment, which may suggest hypothetical bias. Conservationists increasingly argue that conservation should include local communities in management (for both pragmatic and moral reasons). It is heartening that potential conservation donors seem to agree. PMID:29451923

  14. Changes in fish assemblages following the establishment of a network of no-take marine reserves and partially-protected areas.

    Directory of Open Access Journals (Sweden)

    Brendan P Kelaher

    Full Text Available Networks of no-take marine reserves and partially-protected areas (with limited fishing are being increasingly promoted as a means of conserving biodiversity. We examined changes in fish assemblages across a network of marine reserves and two different types of partially-protected areas within a marine park over the first 5 years of its establishment. We used Baited Remote Underwater Video (BRUV to quantify fish communities on rocky reefs at 20-40 m depth between 2008-2011. Each year, we sampled 12 sites in 6 no-take marine reserves and 12 sites in two types of partially-protected areas with contrasting levels of protection (n = 4 BRUV stations per site. Fish abundances were 38% greater across the network of marine reserves compared to the partially-protected areas, although not all individual reserves performed equally. Compliance actions were positively associated with marine reserve responses, while reserve size had no apparent relationship with reserve performance after 5 years. The richness and abundance of fishes did not consistently differ between the two types of partially-protected areas. There was, therefore, no evidence that the more regulated partially-protected areas had additional conservation benefits for reef fish assemblages. Overall, our results demonstrate conservation benefits to fish assemblages from a newly established network of temperate marine reserves. They also show that ecological monitoring can contribute to adaptive management of newly established marine reserve networks, but the extent of this contribution is limited by the rate of change in marine communities in response to protection.

  15. European ecological networks and greenways

    NARCIS (Netherlands)

    Jongman, R.H.G.; Külvik, M.; Kristiansen, I.

    2004-01-01

    In the context of European integration, networks are becoming increasingly important in both social and ecological sense. Since the beginning of the 1990s, societal and scientific exchanges are being restructured as the conceptual approaches towards new nature conservation strategies have been

  16. Seed plant features, distribution patterns, diversity hotspots, and conservation gaps in Xinjiang, China

    Directory of Open Access Journals (Sweden)

    Jihong Huang

    2018-06-01

    Full Text Available The flora in Xinjiang is unique. Decisions about biodiversity conservation and management based on seed plant diversity hotspots and conservation gaps in Xinjiang are essential to maintain this unique flora. Based on a species distribution dataset of seed plants, we measured seed plant diversity using species richness and phylogenetic diversity indices. Five percent of Xinjiang’s total land area with the highest biodiversity was used to identify hotspots for each index. In total, eight hotspots were identified. Most hotspots were located in mountainous areas, mainly in the Tianshan Mountains and Altai Mountains. Furthermore, we detected conservation gaps for Xinjiang’s seed flora hotspots by overlaying nature reserve maps on to maps of identified hotspots and we designated priority conservation gaps for hotspots by overlaying global biodiversity hotspot maps on to hotspot conservation gaps maps. Most of Xinjiang’s seed plant hotspots are poorly protected; only 10.45% of these hotspots were covered by nature reserves. We suggest that it is essential to promote network function of nature reserves within these hotspots in Xinjiang to conserve this unique flora.

  17. 5th International Conference LACONA V (Lasers in the Conservation of Artworks)

    CERN Document Server

    Dickmann, Klaus; Asmus, John F; Lasers in the Conservation of Artworks

    2005-01-01

    Since 1995, when Costas Fotakis first brought together restorers and scientists to discuss the potential of lasers in art conservation, the field has grown enormously in importance, and today restorers and laser scientists work together to develop new applications. This book presents the more than six dozen research papers prepared for LACONA V (Lasers in Art Conservation), held in Osnabrueck/Germany in September 2003. The fifth congress once again gathers restorers, art historians, museum staff, laser scientists and laser manufacturers. The topics include, among others: laser cleaning of artworks (case studies and side effects), removal of former conservation layers, fundamentals of laser-artwork interaction, online monitoring and process control, laser diagnostics, spectroscopy for monitoring and identification, networks and co-operation projects.

  18. Seeing (and Doing) Conservation Through Cultural Lenses

    Science.gov (United States)

    Peterson, Richard B.; Russell, Diane; West, Paige; Brosius, J. Peter

    2010-01-01

    In this paper, we first discuss various vantage points gained through the authors’ experience of approaching conservation through a “cultural lens.” We then draw out more general concerns that many anthropologists hold with respect to conservation, summarizing and commenting on the work of the Conservation and Community Working Group within the Anthropology and Environment Section of the American Anthropological Association. Here we focus on both critiques and contributions the discipline of anthropology makes with regard to conservation, and show how anthropologists are moving beyond conservation critiques to engage actively with conservation practice and policy. We conclude with reflections on the possibilities for enhancing transdisciplinary dialogue and practice through reflexive questioning, the adoption of disciplinary humility, and the realization that “cross-border” collaboration among conservation scholars and practitioners can strengthen the political will necessary to stem the growing commoditization and ensuing degradation of the earth’s ecosystems.

  19. Ten ways remote sensing can contribute to conservation

    Science.gov (United States)

    Rose, Robert A.; Byler, Dirck; Eastman, J. Ron; Fleishman, Erica; Geller, Gary; Goetz, Scott; Guild, Liane; Hamilton, Healy; Hansen, Matt; Headley, Rachel; Hewson, Jennifer; Horning, Ned; Kaplin, Beth A.; Laporte, Nadine; Leidner, Allison K.; Leimgruber, Peter; Morisette, Jeffrey T.; Musinsky, John; Pintea, Lilian; Prados, Ana; Radeloff, Volker C.; Rowen, Mary; Saatchi, Sassan; Schill, Steve; Tabor, Karyn; Turner, Woody; Vodacek, Anthony; Vogelmann, James; Wegmann, Martin; Wilkie, David; Wilson, Cara

    2014-01-01

    In an effort to increase conservation effectiveness through the use of Earth observation technologies, a group of remote sensing scientists affiliated with government and academic institutions and conservation organizations identified 10 questions in conservation for which the potential to be answered would be greatly increased by use of remotely sensed data and analyses of those data. Our goals were to increase conservation practitioners’ use of remote sensing to support their work, increase collaboration between the conservation science and remote sensing communities, identify and develop new and innovative uses of remote sensing for advancing conservation science, provide guidance to space agencies on how future satellite missions can support conservation science, and generate support from the public and private sector in the use of remote sensing data to address the 10 conservation questions. We identified a broad initial list of questions on the basis of an email chain-referral survey. We then used a workshop-based iterative and collaborative approach to whittle the list down to these final questions (which represent 10 major themes in conservation): How can global Earth observation data be used to model species distributions and abundances? How can remote sensing improve the understanding of animal movements? How can remotely sensed ecosystem variables be used to understand, monitor, and predict ecosystem response and resilience to multiple stressors? How can remote sensing be used to monitor the effects of climate on ecosystems? How can near real-time ecosystem monitoring catalyze threat reduction, governance and regulation compliance, and resource management decisions? How can remote sensing inform configuration of protected area networks at spatial extents relevant to populations of target species and ecosystem services? How can remote sensing-derived products be used to value and monitor changes in ecosystem services? How can remote sensing be used to

  20. Hierarchically Coordinated Power Management for Target Tracking in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Feng Juan

    2013-10-01

    Full Text Available Energy efficiency is very important for wireless sensor networks (WSNs since sensor nodes have a limited energy supply from a battery. So far, a lot research has focused on this issue, while less emphasis has been placed on the adaptive sleep time for each node with a consideration for the application constraints. In this paper, we propose a hierarchically coordinated power management (HCPM approach, which both addresses the energy conservation problem and reduces the packet forwarding delay for target tracking WSNs based on a virtual-grid-based network structure. We extend the network lifetime by adopting an adaptive sleep scheduling scheme that combines the local power management (PM and the adaptive coordinate PM strategies to schedule the activities of the sensor nodes at the surveillance stage. Furthermore, we propose a hierarchical structure for the tracking stage. Experimental results show that the proposed approach has a greater capability of extending the network lifetime while maintaining a short transmission delay when compared with the protocol which does not consider the application constraints in target tracking sensor networks.

  1. The structure of additive conservation laws

    International Nuclear Information System (INIS)

    Helmut Reen

    1979-01-01

    All additive conserved quantities are listed for a system with short range central force interaction between the particles: a special case shows up in Boltzmann H-theorem and his derivation of the Maxwell velocity distribution. It is concluded that in classical mechanics of mass points there are no other additive conservation laws besides of energy, momentum, angular momentum and center of mass motion. A generator is considered of a symmetry transformation defined as integral over a conserved local current density where the latter, in general, needs not be covariant under translations

  2. Optimal conservation of migratory species.

    Directory of Open Access Journals (Sweden)

    Tara G Martin

    Full Text Available BACKGROUND: Migratory animals comprise a significant portion of biodiversity worldwide with annual investment for their conservation exceeding several billion dollars. Designing effective conservation plans presents enormous challenges. Migratory species are influenced by multiple events across land and sea-regions that are often separated by thousands of kilometres and span international borders. To date, conservation strategies for migratory species fail to take into account how migratory animals are spatially connected between different periods of the annual cycle (i.e. migratory connectivity bringing into question the utility and efficiency of current conservation efforts. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the first framework for determining an optimal conservation strategy for a migratory species. Employing a decision theoretic approach using dynamic optimization, we address the problem of how to allocate resources for habitat conservation for a Neotropical-Nearctic migratory bird, the American redstart Setophaga ruticilla, whose winter habitat is under threat. Our first conservation strategy used the acquisition of winter habitat based on land cost, relative bird density, and the rate of habitat loss to maximize the abundance of birds on the wintering grounds. Our second strategy maximized bird abundance across the entire range of the species by adding the constraint of maintaining a minimum percentage of birds within each breeding region in North America using information on migratory connectivity as estimated from stable-hydrogen isotopes in feathers. We show that failure to take into account migratory connectivity may doom some regional populations to extinction, whereas including information on migratory connectivity results in the protection of the species across its entire range. CONCLUSIONS/SIGNIFICANCE: We demonstrate that conservation strategies for migratory animals depend critically upon two factors: knowledge of

  3. Emotion shapes the diffusion of moralized content in social networks

    Science.gov (United States)

    Wills, Julian A.; Jost, John T.; Tucker, Joshua A.; Van Bavel, Jay J.

    2017-01-01

    Political debate concerning moralized issues is increasingly common in online social networks. However, moral psychology has yet to incorporate the study of social networks to investigate processes by which some moral ideas spread more rapidly or broadly than others. Here, we show that the expression of moral emotion is key for the spread of moral and political ideas in online social networks, a process we call “moral contagion.” Using a large sample of social media communications about three polarizing moral/political issues (n = 563,312), we observed that the presence of moral-emotional words in messages increased their diffusion by a factor of 20% for each additional word. Furthermore, we found that moral contagion was bounded by group membership; moral-emotional language increased diffusion more strongly within liberal and conservative networks, and less between them. Our results highlight the importance of emotion in the social transmission of moral ideas and also demonstrate the utility of social network methods for studying morality. These findings offer insights into how people are exposed to moral and political ideas through social networks, thus expanding models of social influence and group polarization as people become increasingly immersed in social media networks. PMID:28652356

  4. Spatial overlap between environmental policy instruments and areas of high conservation value in forest.

    Science.gov (United States)

    Sverdrup-Thygeson, Anne; Søgaard, Gunnhild; Rusch, Graciela M; Barton, David N

    2014-01-01

    In order to safeguard biodiversity in forest we need to know how forest policy instruments work. Here we use a nationwide network of 9400 plots in productive forest to analyze to what extent large-scale policy instruments, individually and together, target forest of high conservation value in Norway. We studied both instruments working through direct regulation; Strict Protection and Landscape Protection, and instruments working through management planning and voluntary schemes of forest certification; Wilderness Area and Mountain Forest. As forest of high conservation value (HCV-forest) we considered the extent of 12 Biodiversity Habitats and the extent of Old-Age Forest. We found that 22% of productive forest area contained Biodiversity Habitats. More than 70% of this area was not covered by any large-scale instruments. Mountain Forest covered 23%, while Strict Protection and Wilderness both covered 5% of the Biodiversity Habitat area. A total of 9% of productive forest area contained Old-Age Forest, and the relative coverage of the four instruments was similar as for Biodiversity Habitats. For all instruments, except Landscape Protection, the targeted areas contained significantly higher proportions of HCV-forest than areas not targeted by these instruments. Areas targeted by Strict Protection had higher proportions of HCV-forest than areas targeted by other instruments, except for areas targeted by Wilderness Area which showed similar proportions of Biodiversity Habitats. There was a substantial amount of spatial overlap between the policy tools, but no incremental conservation effect of overlapping instruments in terms of contributing to higher percentages of targeted HCV-forest. Our results reveal that although the current policy mix has an above average representation of forest of high conservation value, the targeting efficiency in terms of area overlap is limited. There is a need to improve forest conservation and a potential to cover this need by better

  5. Entanglement effects in model polymer networks

    Science.gov (United States)

    Everaers, R.; Kremer, K.

    The influence of topological constraints on the local dynamics in cross-linked polymer melts and their contribution to the elastic properties of rubber elastic systems are a long standing problem in statistical mechanics. Polymer networks with diamond lattice connectivity (Everaers and Kremer 1995, Everaers and Kremer 1996a) are idealized model systems which isolate the effect of topology conservation from other sources of quenched disorder. We study their behavior in molecular dynamics simulations under elongational strain. In our analysis we compare the measured, purely entropic shear moduli G to the predictions of statistical mechanical models of rubber elasticity, making extensive use of the microscopic structural and topological information available in computer simulations. We find (Everaers and Kremer 1995) that the classical models of rubber elasticity underestimate the true change in entropy in a deformed network significantly, because they neglect the tension along the contour of the strands which cannot relax due to entanglements (Everaers and Kremer (in preparation)). This contribution and the fluctuations in strained systems seem to be well described by the constrained mode model (Everaers 1998) which allows to treat the crossover from classical rubber elasticity to the tube model for polymer networks with increasing strand length within one transparant formalism. While this is important for the description of the effects we try to do a first quantitative step towards their explanation by topological considerations. We show (Everaers and Kremer 1996a) that for the comparatively short strand lengths of our diamond networks the topology contribution to the shear modulus is proportional to the density of entangled mesh pairs with non-zero Gauss linking number. Moreover, the prefactor can be estimated consistently within a rather simple model developed by Vologodskii et al. and by Graessley and Pearson, which is based on the definition of an entropic

  6. A general framework for performance guaranteed green data center networking

    OpenAIRE

    Wang, Ting; Xia, Yu; Muppala, Jogesh; Hamdi, Mounir; Foufou, Sebti

    2014-01-01

    From the perspective of resource allocation and routing, this paper aims to save as much energy as possible in data center networks. We present a general framework, based on the blocking island paradigm, to try to maximize the network power conservation and minimize sacrifices of network performance and reliability. The bandwidth allocation mechanism together with power-aware routing algorithm achieve a bandwidth guaranteed tighter network. Besides, our fast efficient heuristics for allocatin...

  7. A protein-binding domain, EH, identified in the receptor tyrosine kinase substrate Eps15 and conserved in evolution

    DEFF Research Database (Denmark)

    Wong, W T; Schumacher, C; Salcini, A E

    1995-01-01

    In this report we structurally and functionally define a binding domain that is involved in protein association and that we have designated EH (for Eps15 homology domain). This domain was identified in the tyrosine kinase substrate Eps15 on the basis of regional conservation with several heteroge......In this report we structurally and functionally define a binding domain that is involved in protein association and that we have designated EH (for Eps15 homology domain). This domain was identified in the tyrosine kinase substrate Eps15 on the basis of regional conservation with several...... heterogeneous proteins of yeast and nematode. The EH domain spans about 70 amino acids and shows approximately 60% overall amino acid conservation. We demonstrated the ability of the EH domain to specifically bind cytosolic proteins in normal and malignant cells of mesenchymal, epithelial, and hematopoietic...... (for Eps15-related). Structural comparison of Eps15 and Eps15r defines a family of signal transducers possessing extensive networking abilities including EH-mediated binding and association with Src homology 3-containing proteins....

  8. Comprehensive characterization of lncRNA-mRNA related ceRNA network across 12 major cancers

    Science.gov (United States)

    Feng, Li; Li, Feng; Sun, Zeguo; Wu, Tan; Shi, Xinrui; Li, Jing; Li, Xia

    2016-01-01

    Recent studies indicate that long noncoding RNAs (lncRNAs) can act as competing endogenous RNAs (ceRNAs) to indirectly regulate mRNAs through shared microRNAs, which represents a novel layer of RNA crosstalk and plays critical roles in the development of tumor. However, the global regulation landscape and characterization of these lncRNA related ceRNA crosstalk in cancers is still largely unknown. Here, we systematically characterized the lncRNA related ceRNA interactions across 12 major cancers and the normal physiological states by integrating multidimensional molecule profiles of more than 5000 samples. Our study suggest the large difference of ceRNA regulation between normal and tumor states and the higher similarity across similar tissue origin of tumors. The ceRNA related molecules have more conserved features in tumor networks and they play critical roles in both the normal and tumorigenesis processes. Besides, lncRNAs in the pan-cancer ceRNA network may be potential biomarkers of tumor. By exploring hub lncRNAs, we found that these conserved key lncRNAs dominate variable tumor hallmark processes across pan-cancers. Network dynamic analysis highlights the critical roles of ceRNA regulation in tumorigenesis. By analyzing conserved ceRNA interactions, we found that miRNA mediate ceRNA regulation showed different patterns across pan-cancer; while analyzing the cancer specific ceRNA interactions reveal that lncRNAs synergistically regulated tumor driver genes of cancer hallmarks. Finally, we found that ceRNA modules have the potential to predict patient survival. Overall, our study systematically dissected the lncRNA related ceRNA networks in pan-cancer that shed new light on understanding the molecular mechanism of tumorigenesis. PMID:27580177

  9. Numerical Feedback Stabilization with Applications to Networks

    Directory of Open Access Journals (Sweden)

    Simone Göttlich

    2017-01-01

    Full Text Available The focus is on the numerical consideration of feedback boundary control problems for linear systems of conservation laws including source terms. We explain under which conditions the numerical discretization can be used to design feedback boundary values for network applications such as electric transmission lines or traffic flow systems. Several numerical examples illustrate the properties of the results for different types of networks.

  10. Regulation of metabolic networks by small molecule metabolites

    Directory of Open Access Journals (Sweden)

    Kanehisa Minoru

    2007-03-01

    Full Text Available Abstract Background The ability to regulate metabolism is a fundamental process in living systems. We present an analysis of one of the mechanisms by which metabolic regulation occurs: enzyme inhibition and activation by small molecules. We look at the network properties of this regulatory system and the relationship between the chemical properties of regulatory molecules. Results We find that many features of the regulatory network, such as the degree and clustering coefficient, closely match those of the underlying metabolic network. While these global features are conserved across several organisms, we do find local differences between regulation in E. coli and H. sapiens which reflect their different lifestyles. Chemical structure appears to play an important role in determining a compounds suitability for use in regulation. Chemical structure also often determines how groups of similar compounds can regulate sets of enzymes. These groups of compounds and the enzymes they regulate form modules that mirror the modules and pathways of the underlying metabolic network. We also show how knowledge of chemical structure and regulation could be used to predict regulatory interactions for drugs. Conclusion The metabolic regulatory network shares many of the global properties of the metabolic network, but often varies at the level of individual compounds. Chemical structure is a key determinant in deciding how a compound is used in regulation and for defining modules within the regulatory system.

  11. Identification of conserved drought stress responsive gene-network across tissues and developmental stages in rice.

    Science.gov (United States)

    Smita, Shuchi; Katiyar, Amit; Pandey, Dev Mani; Chinnusamy, Viswanathan; Archak, Sunil; Bansal, Kailash Chander

    2013-01-01

    Identification of genes that are coexpressed across various tissues and environmental stresses is biologically interesting, since they may play coordinated role in similar biological processes. Genes with correlated expression patterns can be best identified by using coexpression network analysis of transcriptome data. In the present study, we analyzed the temporal-spatial coordination of gene expression in root, leaf and panicle of rice under drought stress and constructed network using WGCNA and Cytoscape. Total of 2199 differentially expressed genes (DEGs) were identified in at least three or more tissues, wherein 88 genes have coordinated expression profile among all the six tissues under drought stress. These 88 highly coordinated genes were further subjected to module identification in the coexpression network. Based on chief topological properties we identified 18 hub genes such as ABC transporter, ATP-binding protein, dehydrin, protein phosphatase 2C, LTPL153 - Protease inhibitor, phosphatidylethanolaminebinding protein, lactose permease-related, NADP-dependent malic enzyme, etc. Motif enrichment analysis showed the presence of ABRE cis-elements in the promoters of > 62% of the coordinately expressed genes. Our results suggest that drought stress mediated upregulated gene expression was coordinated through an ABA-dependent signaling pathway across tissues, at least for the subset of genes identified in this study, while down regulation appears to be regulated by tissue specific pathways in rice.

  12. Spatial “Artistic” Networks: From Deconstructing Integer-Functions to Visual Arts

    Directory of Open Access Journals (Sweden)

    Ernesto Estrada

    2018-01-01

    Full Text Available Deconstructivism is an aesthetically appealing architectonic style. Here, we identify some general characteristics of this style, such as decomposition of the whole into parts, superposition of layers, and conservation of the memory of the whole. Using these attributes, we propose a method to deconstruct functions based on integers. Using this integer-function deconstruction we generate spatial networks which display a few artistic attributes such as (i biomorphic shapes, (ii symmetry, and (iii beauty. In building these networks, the deconstructed integer-functions are used as the coordinates of the nodes in a unit square, which are then joined according to a given connection radius like in random geometric graphs (RGGs. Some graph-theoretic invariants of these networks are calculated and compared with the classical RGGs. We then show how these networks inspire an artist to create artistic compositions using mixed techniques on canvas and on paper. Finally, we call for avoiding that the applicability of (network sciences should not go in detriment of curiosity-driven, and aesthetic-driven, researches. We claim that the aesthetic of network research, and not only its applicability, would be an attractor for new minds to this field.

  13. Graph theoretical analysis of resting magnetoencephalographic functional connectivity networks

    Directory of Open Access Journals (Sweden)

    Lindsay eRutter

    2013-07-01

    Full Text Available Complex networks have been observed to comprise small-world properties, believed to represent an optimal organization of local specialization and global integration of information processing at reduced wiring cost. Here, we applied magnitude squared coherence to resting magnetoencephalographic time series in reconstructed source space, acquired from controls and patients with schizophrenia, and generated frequency-dependent adjacency matrices modeling functional connectivity between virtual channels. After configuring undirected binary and weighted graphs, we found that all human networks demonstrated highly localized clustering and short characteristic path lengths. The most conservatively thresholded networks showed efficient wiring, with topographical distance between connected vertices amounting to one-third as observed in surrogate randomized topologies. Nodal degrees of the human networks conformed to a heavy-tailed exponentially truncated power-law, compatible with the existence of hubs, which included theta and alpha bilateral cerebellar tonsil, beta and gamma bilateral posterior cingulate, and bilateral thalamus across all frequencies. We conclude that all networks showed small-worldness, minimal physical connection distance, and skewed degree distributions characteristic of physically-embedded networks, and that these calculations derived from graph theoretical mathematics did not quantifiably distinguish between subject populations, independent of bandwidth. However, post-hoc measurements of edge computations at the scale of the individual vertex revealed trends of reduced gamma connectivity across the posterior medial parietal cortex in patients, an observation consistent with our prior resting activation study that found significant reduction of synthetic aperture magnetometry gamma power across similar regions. The basis of these small differences remains unclear.

  14. A broader view of stewardship to achieve conservation and sustainability goals in South Africa

    Directory of Open Access Journals (Sweden)

    Jaco Barendse

    2016-05-01

    Full Text Available Stewardship is a popular term for the principles and actions aimed at improving sustainability and resilience of social-ecological systems at various scales and in different contexts. Participation in stewardship is voluntary, and is based on values of altruism and long-term benefits. At a global scale, "earth stewardship" is viewed as a successor to earlier natural resource management systems. However, in South Africa, stewardship is narrowly applied to biodiversity conservation agreements on private land. Using a broader definition of stewardship, we identify all potentially related schemes that may contribute to sustainability and conservation outcomes. Stewardship schemes and actors are represented as a social network and placed in a simple typology based on objectives, mechanisms of action and operational scales. The predominant type was biodiversity stewardship programmes. The main actors were environmental non-governmental organisations participating in prominent bioregional landscape partnerships, together acting as important "bridging organisations" within local stewardship networks. This bridging enables a high degree of collaboration between non-governmental and governmental bodies, especially provincial conservation agencies via mutual projects and conservation objectives. An unintended consequence may be that management accountability is relinquished or neglected by government because of inadequate implementation capacity. Other stewardship types, such as market-based and landscape initiatives, complemented primarily biodiversity ones, as part of national spatial conservation priorities. Not all schemes related to biodiversity, especially those involving common pool resources, markets and supply chains. Despite an apparent narrow biodiversity focus, there is evidence of diversification of scope to include more civic and community-level stewardship activities, in line with the earth stewardship metaphor.

  15. On momentum conservation

    International Nuclear Information System (INIS)

    Karastoyanov, A.

    1990-01-01

    The relativistic law of momentum transformation shows that the sum of momenta of even isolated particles is not invariable in all inertial reference systems. This is connected with the relativistic change of kinetic energy and mass of a system of particles in result of internal interactions. The paper proposes a short and simple proof on the necessity of potential momentum. The momentum conservation law (for all interactions in the Minkowski world) is expressed in a generalized form. The constancy of the sum of kinetic and potential momentum of closed system of particles is shown. The energy conservation is a necessary condition. The potential momentum is defined as usual (e.g. as in the Berkeley Physics Course). (author). 13 refs

  16. Interplay between chaperones and protein disorder promotes the evolution of protein networks.

    Directory of Open Access Journals (Sweden)

    Sebastian Pechmann

    2014-06-01

    Full Text Available Evolution is driven by mutations, which lead to new protein functions but come at a cost to protein stability. Non-conservative substitutions are of interest in this regard because they may most profoundly affect both function and stability. Accordingly, organisms must balance the benefit of accepting advantageous substitutions with the possible cost of deleterious effects on protein folding and stability. We here examine factors that systematically promote non-conservative mutations at the proteome level. Intrinsically disordered regions in proteins play pivotal roles in protein interactions, but many questions regarding their evolution remain unanswered. Similarly, whether and how molecular chaperones, which have been shown to buffer destabilizing mutations in individual proteins, generally provide robustness during proteome evolution remains unclear. To this end, we introduce an evolutionary parameter λ that directly estimates the rate of non-conservative substitutions. Our analysis of λ in Escherichia coli, Saccharomyces cerevisiae, and Homo sapiens sequences reveals how co- and post-translationally acting chaperones differentially promote non-conservative substitutions in their substrates, likely through buffering of their destabilizing effects. We further find that λ serves well to quantify the evolution of intrinsically disordered proteins even though the unstructured, thus generally variable regions in proteins are often flanked by very conserved sequences. Crucially, we show that both intrinsically disordered proteins and highly re-wired proteins in protein interaction networks, which have evolved new interactions and functions, exhibit a higher λ at the expense of enhanced chaperone assistance. Our findings thus highlight an intricate interplay of molecular chaperones and protein disorder in the evolvability of protein networks. Our results illuminate the role of chaperones in enabling protein evolution, and underline the

  17. Integrating Ecosystem Management, Protected Areas, and Mammal Conservation in the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Claudia Azevedo-Ramos

    2006-12-01

    Full Text Available The Amazon forest has been converted to a matrix of pristine and modified habitats. Landscape-scale biodiversity conservation requires an understanding of species' distributions over this matrix to guarantee both effective protection and use for present and future generations. In this study, we evaluated how much of the existing and future planned protected areas (PAs would be contributing to the conservation of Brazilian Amazon mammals (N = 399, including threatened species (N = 51. Currently, almost 37% of Brazilian Amazon is protected and that may increase to 46% if planned PAs are implemented. In the current PA system, 22% are indigenous land and 11% are sustainable use units, e.g., production forests. Only one-fifth of the whole range of mammal species occurring in Brazilian Amazon is actually protected by Brazilian PAs. However, considering only the part of the ranges within the Brazilian Amazon, and therefore under the scope of Brazilian actions, Brazilian PAs assume an important role in the protection of 39% of mammal distribution ranges, particularly the threatened species (39%. These results suggest that an integrated network of protected areas among Amazon countries would be necessary to increase their efficiency in mammal conservation. The need for strengthening of the forest sector and good management practices in Brazil appears critical for the maintenance of large extents of forest and species conservation. Under such a scenario, the contribution of developed nations and international agencies must assume an important role for the maintenance and enlargement of the protected area network in Amazon region.

  18. Infection dynamics on spatial small-world network models

    Science.gov (United States)

    Iotti, Bryan; Antonioni, Alberto; Bullock, Seth; Darabos, Christian; Tomassini, Marco; Giacobini, Mario

    2017-11-01

    The study of complex networks, and in particular of social networks, has mostly concentrated on relational networks, abstracting the distance between nodes. Spatial networks are, however, extremely relevant in our daily lives, and a large body of research exists to show that the distances between nodes greatly influence the cost and probability of establishing and maintaining a link. A random geometric graph (RGG) is the main type of synthetic network model used to mimic the statistical properties and behavior of many social networks. We propose a model, called REDS, that extends energy-constrained RGGs to account for the synergic effect of sharing the cost of a link with our neighbors, as is observed in real relational networks. We apply both the standard Watts-Strogatz rewiring procedure and another method that conserves the degree distribution of the network. The second technique was developed to eliminate unwanted forms of spatial correlation between the degree of nodes that are affected by rewiring, limiting the effect on other properties such as clustering and assortativity. We analyze both the statistical properties of these two network types and their epidemiological behavior when used as a substrate for a standard susceptible-infected-susceptible compartmental model. We consider and discuss the differences in properties and behavior between RGGs and REDS as rewiring increases and as infection parameters are changed. We report considerable differences both between the network types and, in the case of REDS, between the two rewiring schemes. We conclude that REDS represent, with the application of these rewiring mechanisms, extremely useful and interesting tools in the study of social and epidemiological phenomena in synthetic complex networks.

  19. Integrating conservation costs into sea level rise adaptive conservation prioritization

    Directory of Open Access Journals (Sweden)

    Mingjian Zhu

    2015-07-01

    Full Text Available Biodiversity conservation requires strategic investment as resources for conservation are often limited. As sea level rises, it is important and necessary to consider both sea level rise and costs in conservation decision making. In this study, we consider costs of conservation in an integrated modeling process that incorporates a geomorphological model (SLAMM, species habitat models, and conservation prioritization (Zonation to identify conservation priorities in the face of landscape dynamics due to sea level rise in the Matanzas River basin of northeast Florida. Compared to conservation priorities that do not consider land costs in the analysis process, conservation priorities that consider costs in the planning process change significantly. The comparison demonstrates that some areas with high conservation values might be identified as lower priorities when integrating economic costs in the planning process and some areas with low conservation values might be identified as high priorities when considering costs in the planning process. This research could help coastal resources managers make informed decisions about where and how to allocate conservation resources more wisely to facilitate biodiversity adaptation to sea level rise.

  20. Incorporating phylogenetic information for the definition of floristic districts in hyperdiverse Amazon forests: Implications for conservation

    OpenAIRE

    Guevara Andino, Juan Ernesto; Pitman, Nigel C. A.; ter Steege, Hans; Mogollón, Hugo; Ceron, Carlos; Palacios, Walter; Oleas, Nora; Fine, Paul V. A.

    2017-01-01

    Abstract Using complementary metrics to evaluate phylogenetic diversity can facilitate the delimitation of floristic units and conservation priority areas. In this study, we describe the spatial patterns of phylogenetic alpha and beta diversity, phylogenetic endemism, and evolutionary distinctiveness of the hyperdiverse Ecuador Amazon forests and define priority areas for conservation. We established a network of 62 one‐hectare plots in terra firme forests of Ecuadorian Amazon. In these plots...

  1. Conservation potential of agricultural water conservation subsidies

    Science.gov (United States)

    Huffaker, Ray

    2008-07-01

    A current policy subsidizes farmers to invest in improved on-farm irrigation efficiency, expecting water to be conserved off farm. Contrary to expectation, water has been increasingly depleted in some regions after such improvements. This paper investigates the policy's failure to conserve water consistently by (1) formulating an economic model of irrigated crop production to determine a profit-maximizing irrigator's range of responses to a subsidy and (2) embedding these responses into hypothetical streamflow diagrams to ascertain their potential to conserve water under various hydrologic regimes. Testable hypotheses are developed to predict the conservation potential of a subsidy in real-world application.

  2. Engaging recreational fishers in management and conservation: global case studies.

    Science.gov (United States)

    Granek, E F; Madin, E M P; Brown, M A; Figueira, W; Cameron, D S; Hogan, Z; Kristianson, G; de Villiers, P; Williams, J E; Post, J; Zahn, S; Arlinghaus, R

    2008-10-01

    Globally, the number of recreational fishers is sizeable and increasing in many countries. Associated with this trend is the potential for negative impacts on fish stocks through exploitation or management measures such as stocking and introduction of non-native fishes. Nevertheless, recreational fishers can be instrumental in successful fisheries conservation through active involvement in, or initiation of, conservation projects to reduce both direct and external stressors contributing to fishery declines. Understanding fishers' concerns for sustained access to the resource and developing methods for their meaningful participation can have positive impacts on conservation efforts. We examined a suite of case studies that demonstrate successful involvement of recreational fishers in conservation and management activities that span developed and developing countries, temperate and tropical regions, marine and freshwater systems, and open- and closed-access fisheries. To illustrate potential benefits and challenges of involving recreational fishers in fisheries management and conservation, we examined the socioeconomic and ecological contexts of each case study. We devised a conceptual framework for the engagement of recreational fishers that targets particular types of involvement (enforcement, advocacy, conservation, management design [type and location], research, and monitoring) on the basis of degree of stakeholder stewardship, scale of the fishery, and source of impacts (internal or external). These activities can be enhanced by incorporating local knowledge and traditions, taking advantage of leadership and regional networks, and creating collaborations among various stakeholder groups, scientists, and agencies to maximize the probability of recreational fisher involvement and project success.

  3. Conservation businesses and conservation planning in a biological diversity hotspot.

    Science.gov (United States)

    Di Minin, Enrico; Macmillan, Douglas Craig; Goodman, Peter Styan; Escott, Boyd; Slotow, Rob; Moilanen, Atte

    2013-08-01

    The allocation of land to biological diversity conservation competes with other land uses and the needs of society for development, food, and extraction of natural resources. Trade-offs between biological diversity conservation and alternative land uses are unavoidable, given the realities of limited conservation resources and the competing demands of society. We developed a conservation-planning assessment for the South African province of KwaZulu-Natal, which forms the central component of the Maputaland-Pondoland-Albany biological diversity hotspot. Our objective was to enhance biological diversity protection while promoting sustainable development and providing spatial guidance in the resolution of potential policy conflicts over priority areas for conservation at risk of transformation. The conservation-planning assessment combined spatial-distribution models for 646 conservation features, spatial economic-return models for 28 alternative land uses, and spatial maps for 4 threats. Nature-based tourism businesses were competitive with other land uses and could provide revenues of >US$60 million/year to local stakeholders and simultaneously help meeting conservation goals for almost half the conservation features in the planning region. Accounting for opportunity costs substantially decreased conflicts between biological diversity, agricultural use, commercial forestry, and mining. Accounting for economic benefits arising from conservation and reducing potential policy conflicts with alternative plans for development can provide opportunities for successful strategies that combine conservation and sustainable development and facilitate conservation action. © 2013 Society for Conservation Biology.

  4. Mass and momentum conservation for fluid simulation

    KAUST Repository

    Lentine, Michael; Aanjaneya, Mridul; Fedkiw, Ronald

    2011-01-01

    Momentum conservation has long been used as a design principle for solid simulation (e.g. collisions between rigid bodies, mass-spring elastic and damping forces, etc.), yet it has not been widely used for fluid simulation. In fact, semi-Lagrangian advection does not conserve momentum, but is still regularly used as a bread and butter method for fluid simulation. In this paper, we propose a modification to the semi-Lagrangian method in order to make it fully conserve momentum. While methods of this type have been proposed earlier in the computational physics literature, they are not necessarily appropriate for coarse grids, large time steps or inviscid flows, all of which are common in graphics applications. In addition, we show that the commonly used vorticity confinement turbulence model can be modified to exactly conserve momentum as well. We provide a number of examples that illustrate the benefits of this new approach, both in conserving fluid momentum and passively advected scalars such as smoke density. In particular, we show that our new method is amenable to efficient smoke simulation with one time step per frame, whereas the traditional non-conservative semi-Lagrangian method experiences serious artifacts when run with these large time steps, especially when object interaction is considered. Copyright © 2011 by the Association for Computing Machinery, Inc.

  5. Using social-network research to improve outcomes in natural resource management.

    Science.gov (United States)

    Groce, Julie E; Farrelly, Megan A; Jorgensen, Bradley S; Cook, Carly N

    2018-05-08

    The conservation and management of natural resources operates within social-ecological systems, in which resource users are embedded in social and environmental contexts that influence their management decisions. Characterizing social networks of resource users has received growing interest as an approach for understanding social influences on decision-making, and social network analysis (SNA) has emerged as a useful technique to explore these relationships. In this review, we synthesize how SNA has been used in studies of natural resource management. To present our findings, we developed a theory of change which outlines the influence between social networks and social processes (e.g., interactions between individuals), which in turn influence social outcomes (e.g., decisions or actions) that impact environmental outcomes (e.g., improved condition). Our review of 85 studies demonstrate frequent use of descriptive methods to characterize social processes, yet few studies considered social outcomes or examined network structure relative to environmental outcomes. Only 4 studies assessed network interventions intended to impact relevant processes or outcomes. The heterogeneity in case studies, methods, and analyses preclude general lessons. Thus, we offer a typology of appropriate measures for each stage of our theory of change, to structure and progress our learning about the role of social networks in achieving environmental outcomes. In addition, we suggest shifts in research foci towards intervention studies, to aid in understanding causality and inform the design of conservation initiatives. We also identify the need for developing clearer justification and guidance around the proliferation of network measures. The use of SNA in natural resource management is expanding rapidly, thus now is the ideal time for the conservation community to build a more rigorous evidence base to demonstrate the extent to which social networks can play a role in achieving desired

  6. BinAligner: a heuristic method to align biological networks.

    Science.gov (United States)

    Yang, Jialiang; Li, Jun; Grünewald, Stefan; Wan, Xiu-Feng

    2013-01-01

    The advances in high throughput omics technologies have made it possible to characterize molecular interactions within and across various species. Alignments and comparison of molecular networks across species will help detect orthologs and conserved functional modules and provide insights on the evolutionary relationships of the compared species. However, such analyses are not trivial due to the complexity of network and high computational cost. Here we develop a mixture of global and local algorithm, BinAligner, for network alignments. Based on the hypotheses that the similarity between two vertices across networks would be context dependent and that the information from the edges and the structures of subnetworks can be more informative than vertices alone, two scoring schema, 1-neighborhood subnetwork and graphlet, were introduced to derive the scoring matrices between networks, besides the commonly used scoring scheme from vertices. Then the alignment problem is formulated as an assignment problem, which is solved by the combinatorial optimization algorithm, such as the Hungarian method. The proposed algorithm was applied and validated in aligning the protein-protein interaction network of Kaposi's sarcoma associated herpesvirus (KSHV) and that of varicella zoster virus (VZV). Interestingly, we identified several putative functional orthologous proteins with similar functions but very low sequence similarity between the two viruses. For example, KSHV open reading frame 56 (ORF56) and VZV ORF55 are helicase-primase subunits with sequence identity 14.6%, and KSHV ORF75 and VZV ORF44 are tegument proteins with sequence identity 15.3%. These functional pairs can not be identified if one restricts the alignment into orthologous protein pairs. In addition, BinAligner identified a conserved pathway between two viruses, which consists of 7 orthologous protein pairs and these proteins are connected by conserved links. This pathway might be crucial for virus packing and

  7. Receiver-Assisted Congestion Control to Achieve High Throughput in Lossy Wireless Networks

    Science.gov (United States)

    Shi, Kai; Shu, Yantai; Yang, Oliver; Luo, Jiarong

    2010-04-01

    Many applications would require fast data transfer in high-speed wireless networks nowadays. However, due to its conservative congestion control algorithm, Transmission Control Protocol (TCP) cannot effectively utilize the network capacity in lossy wireless networks. In this paper, we propose a receiver-assisted congestion control mechanism (RACC) in which the sender performs loss-based control, while the receiver is performing delay-based control. The receiver measures the network bandwidth based on the packet interarrival interval and uses it to compute a congestion window size deemed appropriate for the sender. After receiving the advertised value feedback from the receiver, the sender then uses the additive increase and multiplicative decrease (AIMD) mechanism to compute the correct congestion window size to be used. By integrating the loss-based and the delay-based congestion controls, our mechanism can mitigate the effect of wireless losses, alleviate the timeout effect, and therefore make better use of network bandwidth. Simulation and experiment results in various scenarios show that our mechanism can outperform conventional TCP in high-speed and lossy wireless environments.

  8. A predicted protein interactome identifies conserved global networks and disease resistance subnetworks in maize.

    Directory of Open Access Journals (Sweden)

    Matt eGeisler

    2015-06-01

    Full Text Available Interactomes are genome-wide roadmaps of protein-protein interactions. They have been produced for humans, yeast, the fruit fly, and Arabidopsis thaliana and have become invaluable tools for generating and testing hypotheses. A predicted interactome for Zea mays (PiZeaM is presented here as an aid to the research community for this valuable crop species. PiZeaM was built using a proven method of interologs (interacting orthologs that were identified using both one-to-one and many-to-many orthology between genomes of maize and reference species. Where both maize orthologs occurred for an experimentally determined interaction in the reference species, we predicted a likely interaction in maize. A total of 49,026 unique interactions for 6,004 maize proteins were predicted. These interactions are enriched for processes that are evolutionarily conserved, but include many otherwise poorly annotated proteins in maize. The predicted maize interactions were further analyzed by comparing annotation of interacting proteins, including different layers of ontology. A map of pairwise gene co-expression was also generated and compared to predicted interactions. Two global subnetworks were constructed for highly conserved interactions. These subnetworks showed clear clustering of proteins by function. Another subnetwork was created for disease response using a bait and prey strategy to capture interacting partners for proteins that respond to other organisms. Closer examination of this subnetwork revealed the connectivity between biotic and abiotic hormone stress pathways. We believe PiZeaM will provide a useful tool for the prediction of protein function and analysis of pathways for Z. mays researchers and is presented in this paper as a reference tool for the exploration of protein interactions in maize.

  9. A network model framework for prioritizing wetland conservation in the Great Plains

    Science.gov (United States)

    Albanese, Gene; Haukos, David A.

    2017-01-01

    ContextPlaya wetlands are the primary habitat for numerous wetland-dependent species in the Southern Great Plains of North America. Plant and wildlife populations that inhabit these wetlands are reciprocally linked through the dispersal of individuals, propagules and ultimately genes among local populations.ObjectiveTo develop and implement a framework using network models for conceptualizing, representing and analyzing potential biological flows among 48,981 spatially discrete playa wetlands in the Southern Great Plains.MethodsWe examined changes in connectivity patterns and assessed the relative importance of wetlands to maintaining these patterns by targeting wetlands for removal based on network centrality metrics weighted by estimates of habitat quality and probability of inundation.ResultsWe identified several distinct, broad-scale sub networks and phase transitions among playa wetlands in the Southern Plains. In particular, for organisms that can disperse >2 km a dense and expansive wetland sub network emerges in the Southern High Plains. This network was characterized by localized, densely connected wetland clusters at link distances (h) >2 km but <5 km and was most sensitive to changes in wetland availability (p) and configuration when h = 4 km, and p = 0.2–0.4. It transitioned to a single, large connected wetland system at broader spatial scales even when the proportion of inundated wetland was relatively low (p = 0.2).ConclusionsOur findings suggest that redundancy in the potential for broad and fine-scale movements insulates this system from damage and facilitates system-wide connectivity among populations with different dispersal capacities.

  10. The ribonucleoprotein Csr network.

    Science.gov (United States)

    Seyll, Ethel; Van Melderen, Laurence

    2013-11-08

    Ribonucleoprotein complexes are essential regulatory components in bacteria. In this review, we focus on the carbon storage regulator (Csr) network, which is well conserved in the bacterial world. This regulatory network is composed of the CsrA master regulator, its targets and regulators. CsrA binds to mRNA targets and regulates translation either negatively or positively. Binding to small non-coding RNAs controls activity of this protein. Expression of these regulators is tightly regulated at the level of transcription and stability by various global regulators (RNAses, two-component systems, alarmone). We discuss the implications of these complex regulations in bacterial adaptation.

  11. Why Conferences Matter—An Illustration from the International Marine Conservation Congress

    Directory of Open Access Journals (Sweden)

    Samantha Oester

    2017-08-01

    Full Text Available A major activity in the life of an academic is the professional conference. It is common knowledge that this is a place to present your research, but what about other benefits of attending a conference? Online surveys were distributed to delegates of the 3rd and 4th International Marine Conservation Congresses (IMCCs, with respondents' (n = 100 feedback including that the congresses provided useful new information that will aid: (1 their research (58%; (2 in-the-field conservation (29%; (3 conservation communication (46%; and (4 conservation and management policy making (45%. They also reported gaining new techniques (56%, skills (64%, and novel ideas (70% to further their research/careers. Nearly all (91% gained new contacts that improved their research, in-the-field conservation, science communication, and/or conservation policy making. Two thirds (64% gained ideas, contacts, and/or lessons could lead to publications. Over a third (39% gained new ideas, contacts and/or lessons that led to grant proposals, and 36% gained contacts that led to funding. A conference is not just an avenue for a scientist to present their research to the wider community, but it can be an important venue for brainstorming, networking and making vital connections that can lead to new initiatives, papers and funding, in a way that virtual, online meetings cannot. This is why conferences matter.

  12. Conservation and Development in Latin America and Southern Africa: Setting the Stage

    Directory of Open Access Journals (Sweden)

    Claudia Romero

    2012-06-01

    Full Text Available The articles in this Special Feature stem from a 2010 conference (Bridging Conservation and Development in Latin America and Africa organized by the University of Florida's Tropical Conservation Development Program, Center for African Studies, and Center for Latin American Studies. The conference involved researchers and practitioners from Africa and Latin America focused on the complex and evolving relationship between conservation and development. The conference provided bridges between academics and non-academics, conservation and development, and theory and practice. The resulting comparative analyses focus on: empowerment of local institutions; enhanced capacity of local and regional stakeholders through a recognition and validation of local knowledge systems and the creation of knowledge networks; understanding of social and natural landscapes, history, contexts, and their evolution; and the roles of economic and market forces in shaping opportunities for using market-based incentives to promote conservation and development. In this introductory article we propose a conceptual framework based on the six connected pillars of natural resource characteristics, interactions of social actors, governance and participation, politics, information exchange, and economic issues that support spaces for both conflicts and synergies between conservation and development goals. Our goal is to foster informed dialogue and social learning to promote sustainability.

  13. Global sea turtle conservation successes.

    Science.gov (United States)

    Mazaris, Antonios D; Schofield, Gail; Gkazinou, Chrysoula; Almpanidou, Vasiliki; Hays, Graeme C

    2017-09-01

    We document a tendency for published estimates of population size in sea turtles to be increasing rather than decreasing across the globe. To examine the population status of the seven species of sea turtle globally, we obtained 299 time series of annual nesting abundance with a total of 4417 annual estimates. The time series ranged in length from 6 to 47 years (mean, 16.2 years). When levels of abundance were summed within regional management units (RMUs) for each species, there were upward trends in 12 RMUs versus downward trends in 5 RMUs. This prevalence of more upward than downward trends was also evident in the individual time series, where we found 95 significant increases in abundance and 35 significant decreases. Adding to this encouraging news for sea turtle conservation, we show that even small sea turtle populations have the capacity to recover, that is, Allee effects appear unimportant. Positive trends in abundance are likely linked to the effective protection of eggs and nesting females, as well as reduced bycatch. However, conservation concerns remain, such as the decline in leatherback turtles in the Eastern and Western Pacific. Furthermore, we also show that, often, time series are too short to identify trends in abundance. Our findings highlight the importance of continued conservation and monitoring efforts that underpin this global conservation success story.

  14. Value Network of Amazon Non Timber Forest Products: A Mapping Tool to Support a Complex Network Strategic Planning

    OpenAIRE

    Straatmann , Jeferson; Gerolamo , Mateus ,; Carpinetti , Luiz

    2011-01-01

    Part 3: Value Chain for Enhancing Collaborative Networks; International audience; The Non Timber Forest Products (NTFP) value chains are viewed as an alternative for the forest conservation and for the improvement of life conditions of Traditional Communities. These products are part of different chemical, cosmetic, food and pharmaceutical industries, which are trying to improve the sustainability of their supply chains. For the improvement of inter-organizational NTFP network in the Amazon r...

  15. Systems Genetic Analyses Highlight a TGFβ-FOXO3 Dependent Striatal Astrocyte Network Conserved across Species and Associated with Stress, Sleep, and Huntington's Disease.

    Science.gov (United States)

    Scarpa, Joseph R; Jiang, Peng; Losic, Bojan; Readhead, Ben; Gao, Vance D; Dudley, Joel T; Vitaterna, Martha H; Turek, Fred W; Kasarskis, Andrew

    2016-07-01

    Recent systems-based analyses have demonstrated that sleep and stress traits emerge from shared genetic and transcriptional networks, and clinical work has elucidated the emergence of sleep dysfunction and stress susceptibility as early symptoms of Huntington's disease. Understanding the biological bases of these early non-motor symptoms may reveal therapeutic targets that prevent disease onset or slow disease progression, but the molecular mechanisms underlying this complex clinical presentation remain largely unknown. In the present work, we specifically examine the relationship between these psychiatric traits and Huntington's disease (HD) by identifying striatal transcriptional networks shared by HD, stress, and sleep phenotypes. First, we utilize a systems-based approach to examine a large publicly available human transcriptomic dataset for HD (GSE3790 from GEO) in a novel way. We use weighted gene coexpression network analysis and differential connectivity analyses to identify transcriptional networks dysregulated in HD, and we use an unbiased ranking scheme that leverages both gene- and network-level information to identify a novel astrocyte-specific network as most relevant to HD caudate. We validate this result in an independent HD cohort. Next, we computationally predict FOXO3 as a regulator of this network, and use multiple publicly available in vitro and in vivo experimental datasets to validate that this astrocyte HD network is downstream of a signaling pathway important in adult neurogenesis (TGFβ-FOXO3). We also map this HD-relevant caudate subnetwork to striatal transcriptional networks in a large (n = 100) chronically stressed (B6xA/J)F2 mouse population that has been extensively phenotyped (328 stress- and sleep-related measurements), and we show that this striatal astrocyte network is correlated to sleep and stress traits, many of which are known to be altered in HD cohorts. We identify causal regulators of this network through Bayesian network

  16. Land market feedbacks can undermine biodiversity conservation.

    Science.gov (United States)

    Armsworth, Paul R; Daily, Gretchen C; Kareiva, Peter; Sanchirico, James N

    2006-04-04

    The full or partial purchase of land has become a cornerstone of efforts to conserve biodiversity in countries with strong private property rights. Methods used to target areas for acquisition typically ignore land market dynamics. We show how conservation purchases affect land prices and generate feedbacks that can undermine conservation goals, either by displacing development toward biologically valuable areas or by accelerating its pace. The impact of these market feedbacks on the effectiveness of conservation depends on the ecological value of land outside nature reserves. Traditional, noneconomic approaches to site prioritization should perform adequately in places where land outside reserves supports little biodiversity. However, these approaches will perform poorly in locations where the countryside surrounding reserves is important for species' persistence. Conservation investments can sometimes even be counterproductive, condemning more species than they save. Conservation is most likely to be compromised in the absence of accurate information on species distributions, which provides a strong argument for improving inventories of biodiversity. Accounting for land market dynamics in conservation planning is crucial for making smart investment decisions.

  17. Functional coupling networks inferred from prefrontal cortex activity show experience-related effective plasticity

    Directory of Open Access Journals (Sweden)

    Gaia Tavoni

    2017-10-01

    Full Text Available Functional coupling networks are widely used to characterize collective patterns of activity in neural populations. Here, we ask whether functional couplings reflect the subtle changes, such as in physiological interactions, believed to take place during learning. We infer functional network models reproducing the spiking activity of simultaneously recorded neurons in prefrontal cortex (PFC of rats, during the performance of a cross-modal rule shift task (task epoch, and during preceding and following sleep epochs. A large-scale study of the 96 recorded sessions allows us to detect, in about 20% of sessions, effective plasticity between the sleep epochs. These coupling modifications are correlated with the coupling values in the task epoch, and are supported by a small subset of the recorded neurons, which we identify by means of an automatized procedure. These potentiated groups increase their coativation frequency in the spiking data between the two sleep epochs, and, hence, participate to putative experience-related cell assemblies. Study of the reactivation dynamics of the potentiated groups suggests a possible connection with behavioral learning. Reactivation is largely driven by hippocampal ripple events when the rule is not yet learned, and may be much more autonomous, and presumably sustained by the potentiated PFC network, when learning is consolidated. Cell assemblies coding for memories are widely believed to emerge through synaptic modification resulting from learning, yet their identification from activity is very arduous. We propose a functional-connectivity-based approach to identify experience-related cell assemblies from multielectrode recordings in vivo, and apply it to the prefrontal cortex activity of rats recorded during a task epoch and the preceding and following sleep epochs. We infer functional couplings between the recorded cells in each epoch. Comparisons of the functional coupling networks across the epochs allow us

  18. A multiscale network analysis of protected-area connectivity for mammals in the United States.

    Science.gov (United States)

    Minor, Emily S; Lookingbill, Todd R

    2010-12-01

    Protected areas must be close, or connected, enough to allow for the preservation of large-scale ecological and evolutionary processes, such as gene flow, migration, and range shifts in response to climate change. Nevertheless, it is unknown whether the network of protected areas in the United States is connected in a way that will preserve biodiversity over large temporal and spatial scales. It is also unclear whether protected-area networks that function for larger species will function for smaller species. We assessed the connectivity of protected areas in the three largest biomes in the United States. With methods from graph theory--a branch of mathematics that deals with connectivity and flow--we identified and measured networks of protected areas for three different groups of mammals. We also examined the value of using umbrella species (typically large-bodied, far-ranging mammals) in designing large-scale networks of protected areas. Although the total amount of protected land varied greatly among biomes in the United States, overall connectivity did not. In general, protected-area networks were well connected for large mammals but not for smaller mammals. Additionally, it was not possible to predict connectivity for small mammals on the basis of connectivity for large mammals, which suggests the umbrella species approach may not be an appropriate design strategy for conservation networks intended to protect many species. Our findings indicate different strategies should be used to increase the likelihood of persistence for different groups of species. Strategic linkages of existing lands should be a conservation priority for smaller mammals, whereas conservation of larger mammals would benefit most from the protection of more land. © 2010 Society for Conservation Biology.

  19. Gene co-regulation is highly conserved in the evolution of eukaryotes and prokaryotes.

    NARCIS (Netherlands)

    Snel, B.; Noort, V. van; Huynen, M.A.

    2004-01-01

    Differences between species have been suggested to largely reside in the network of connections among the genes. Nevertheless, the rate at which these connections evolve has not been properly quantified. Here, we measure the extent to which co-regulation between pairs of genes is conserved over

  20. The Importance of Rotational Crops for Biodiversity Conservation in Mediterranean Areas.

    Science.gov (United States)

    Chiatante, Gianpasquale; Meriggi, Alberto

    2016-01-01

    Nowadays we are seeing the largest biodiversity loss since the extinction of the dinosaurs. To conserve biodiversity it is essential to plan protected areas using a prioritization approach, which takes into account the current biodiversity value of the sites. Considering that in the Mediterranean Basin the agro-ecosystems are one of the most important parts of the landscape, the conservation of crops is essential to biodiversity conservation. In the framework of agro-ecosystem conservation, farmland birds play an important role because of their representativeness, and because of their steady decline in the last Century in Western Europe. The main aim of this research was to define if crop dominated landscapes could be useful for biodiversity conservation in a Mediterranean area in which the landscape was modified by humans in the last thousand years and was affected by the important biogeographical phenomenon of peninsula effect. To assess this, we identify the hotspots and the coldspots of bird diversity in southern Italy both during the winter and in the breeding season. In particular we used a scoring method, defining a biodiversity value for each cell of a 1-km grid superimposed on the study area, using data collected by fieldwork following a stratified random sampling design. This value was analysed by a multiple linear regression analysis and was predicted in the whole study area. Then we defined the hotspots and the coldspots of the study area as 15% of the cells with higher and lower value of biodiversity, respectively. Finally, we used GAP analysis to compare hotspot distribution with the current network of protected areas. This study showed that the winter hotspots of bird diversity were associated with marshes and water bodies, shrublands, and irrigated crops, whilst the breeding hotspots were associated with more natural areas (e.g. transitional wood/shrubs), such as open areas (natural grasslands, pastures and not irrigated crops). Moreover, the

  1. The Importance of Rotational Crops for Biodiversity Conservation in Mediterranean Areas.

    Directory of Open Access Journals (Sweden)

    Gianpasquale Chiatante

    Full Text Available Nowadays we are seeing the largest biodiversity loss since the extinction of the dinosaurs. To conserve biodiversity it is essential to plan protected areas using a prioritization approach, which takes into account the current biodiversity value of the sites. Considering that in the Mediterranean Basin the agro-ecosystems are one of the most important parts of the landscape, the conservation of crops is essential to biodiversity conservation. In the framework of agro-ecosystem conservation, farmland birds play an important role because of their representativeness, and because of their steady decline in the last Century in Western Europe. The main aim of this research was to define if crop dominated landscapes could be useful for biodiversity conservation in a Mediterranean area in which the landscape was modified by humans in the last thousand years and was affected by the important biogeographical phenomenon of peninsula effect. To assess this, we identify the hotspots and the coldspots of bird diversity in southern Italy both during the winter and in the breeding season. In particular we used a scoring method, defining a biodiversity value for each cell of a 1-km grid superimposed on the study area, using data collected by fieldwork following a stratified random sampling design. This value was analysed by a multiple linear regression analysis and was predicted in the whole study area. Then we defined the hotspots and the coldspots of the study area as 15% of the cells with higher and lower value of biodiversity, respectively. Finally, we used GAP analysis to compare hotspot distribution with the current network of protected areas. This study showed that the winter hotspots of bird diversity were associated with marshes and water bodies, shrublands, and irrigated crops, whilst the breeding hotspots were associated with more natural areas (e.g. transitional wood/shrubs, such as open areas (natural grasslands, pastures and not irrigated crops

  2. A Hybrid Energy Efficient Protocol for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Niranjan Kumar Ray

    2016-01-01

    Full Text Available We proposed an energy conservation technique called Location Based Topology Control with Sleep Scheduling for ad hoc networks. It uses the feature of both topology control approach and power management approach. Like the topology control approach, it attempts to reduce the transmission power of a node, which is determined from its neighborhood location information. A node goes to sleep state based on the traffic condition as that of power management approach. In the proposed scheme, a node goes to sleep state only when its absence does not create local partition in its neighborhood. We preformed extensive simulation to compare the proposed scheme with existing ones. Simulation results show that the energy consumption is lower with increase in the network lifetime and higher throughput in the proposed scheme.

  3. Neuron-Like Networks Between Ribosomal Proteins Within the Ribosome

    Science.gov (United States)

    Poirot, Olivier; Timsit, Youri

    2016-05-01

    From brain to the World Wide Web, information-processing networks share common scale invariant properties. Here, we reveal the existence of neural-like networks at a molecular scale within the ribosome. We show that with their extensions, ribosomal proteins form complex assortative interaction networks through which they communicate through tiny interfaces. The analysis of the crystal structures of 50S eubacterial particles reveals that most of these interfaces involve key phylogenetically conserved residues. The systematic observation of interactions between basic and aromatic amino acids at the interfaces and along the extension provides new structural insights that may contribute to decipher the molecular mechanisms of signal transmission within or between the ribosomal proteins. Similar to neurons interacting through “molecular synapses”, ribosomal proteins form a network that suggest an analogy with a simple molecular brain in which the “sensory-proteins” innervate the functional ribosomal sites, while the “inter-proteins” interconnect them into circuits suitable to process the information flow that circulates during protein synthesis. It is likely that these circuits have evolved to coordinate both the complex macromolecular motions and the binding of the multiple factors during translation. This opens new perspectives on nanoscale information transfer and processing.

  4. Conserved Responses in a War of Small Molecules between a Plant-Pathogenic Bacterium and Fungi.

    Science.gov (United States)

    Spraker, Joseph E; Wiemann, Philipp; Baccile, Joshua A; Venkatesh, Nandhitha; Schumacher, Julia; Schroeder, Frank C; Sanchez, Laura M; Keller, Nancy P

    2018-05-22

    Small-molecule signaling is one major mode of communication within the polymicrobial consortium of soil and rhizosphere. While microbial secondary metabolite (SM) production and responses of individual species have been studied extensively, little is known about potentially conserved roles of SM signals in multilayered symbiotic or antagonistic relationships. Here, we characterize the SM-mediated interaction between the plant-pathogenic bacterium Ralstonia solanacearum and the two plant-pathogenic fungi Fusarium fujikuroi and Botrytis cinerea We show that cellular differentiation and SM biosynthesis in F. fujikuroi are induced by the bacterially produced lipopeptide ralsolamycin (synonym ralstonin A). In particular, fungal bikaverin production is induced and preferentially accumulates in fungal survival spores (chlamydospores) only when exposed to supernatants of ralsolamycin-producing strains of R. solanacearum Although inactivation of bikaverin biosynthesis moderately increases chlamydospore invasion by R. solanacearum , we show that other metabolites such as beauvericin are also induced by ralsolamycin and contribute to suppression of R. solanacearum growth in vitro Based on our findings that bikaverin antagonizes R. solanacearum and that ralsolamycin induces bikaverin biosynthesis in F. fujikuroi , we asked whether other bikaverin-producing fungi show similar responses to ralsolamycin. Examining a strain of B. cinerea that horizontally acquired the bikaverin gene cluster from Fusarium , we found that ralsolamycin induced bikaverin biosynthesis in this fungus. Our results suggest that conservation of microbial SM responses across distantly related fungi may arise from horizontal transfer of protective gene clusters that are activated by conserved regulatory cues, e.g., a bacterial lipopeptide, providing consistent fitness advantages in dynamic polymicrobial networks. IMPORTANCE Bacteria and fungi are ubiquitous neighbors in many environments, including

  5. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    Energy Technology Data Exchange (ETDEWEB)

    Gangi Setty, Thanuja [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Cho, Christine [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Govindappa, Sowmya [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Apicella, Michael A. [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Ramaswamy, S., E-mail: ramas@instem.res.in [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India)

    2014-07-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states.

  6. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    International Nuclear Information System (INIS)

    Gangi Setty, Thanuja; Cho, Christine; Govindappa, Sowmya; Apicella, Michael A.; Ramaswamy, S.

    2014-01-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states

  7. Unravelling Darwin's entangled bank: architecture and robustness of mutualistic networks with multiple interaction types.

    Science.gov (United States)

    Dáttilo, Wesley; Lara-Rodríguez, Nubia; Jordano, Pedro; Guimarães, Paulo R; Thompson, John N; Marquis, Robert J; Medeiros, Lucas P; Ortiz-Pulido, Raul; Marcos-García, Maria A; Rico-Gray, Victor

    2016-11-30

    Trying to unravel Darwin's entangled bank further, we describe the architecture of a network involving multiple forms of mutualism (pollination by animals, seed dispersal by birds and plant protection by ants) and evaluate whether this multi-network shows evidence of a structure that promotes robustness. We found that species differed strongly in their contributions to the organization of the multi-interaction network, and that only a few species contributed to the structuring of these patterns. Moreover, we observed that the multi-interaction networks did not enhance community robustness compared with each of the three independent mutualistic networks when analysed across a range of simulated scenarios of species extinction. By simulating the removal of highly interacting species, we observed that, overall, these species enhance network nestedness and robustness, but decrease modularity. We discuss how the organization of interlinked mutualistic networks may be essential for the maintenance of ecological communities, and therefore the long-term ecological and evolutionary dynamics of interactive, species-rich communities. We suggest that conserving these keystone mutualists and their interactions is crucial to the persistence of species-rich mutualistic assemblages, mainly because they support other species and shape the network organization. © 2016 The Author(s).

  8. Widespread evolutionary conservation of alternatively spliced exons in caenorhabditis

    DEFF Research Database (Denmark)

    Irimia, Manuel; Rukov, Jakob L; Penny, David

    2007-01-01

    Alternative splicing (AS) contributes to increased transcriptome and proteome diversity in various eukaryotic lineages. Previous studies showed low levels of conservation of alternatively spliced (cassette) exons within mammals and within dipterans. We report a strikingly different pattern...... in Caenorhabditis nematodes-more than 92% of cassette exons from Caenorhabditis elegans are conserved in Caenorhabditis briggsae and/or Caenorhabditis remanei. High levels of conservation extend to minor-form exons (present in a minority of transcripts) and are particularly pronounced for exons showing complex...... patterns of splicing. The functionality of the vast majority of cassette exons is underscored by various other features. We suggest that differences in conservation between lineages reflect differences in levels of functionality and further suggest that these differences are due to differences in intron...

  9. Ecological and economic conditions and associated institutional challenges for conservation banking in dynamic landscapes

    NARCIS (Netherlands)

    Teeffelen, van A.J.A.; Opdam, P.F.M.; Wätzold, F.; Hartig, F.; Johst, K.; Drechsler, M.; Vos, C.C.; Wissel, S.; Quétier, F.

    2014-01-01

    Protected areas are a cornerstone of current biodiversity policy. The continued loss of biodiversity, however, as well as the limited scope to extend protected area networks necessitates a conservation perspective that encompasses both protected areas and the wider landscape. This calls for policy

  10. Residue Geometry Networks: A Rigidity-Based Approach to the Amino Acid Network and Evolutionary Rate Analysis

    Science.gov (United States)

    Fokas, Alexander S.; Cole, Daniel J.; Ahnert, Sebastian E.; Chin, Alex W.

    2016-01-01

    Amino acid networks (AANs) abstract the protein structure by recording the amino acid contacts and can provide insight into protein function. Herein, we describe a novel AAN construction technique that employs the rigidity analysis tool, FIRST, to build the AAN, which we refer to as the residue geometry network (RGN). We show that this new construction can be combined with network theory methods to include the effects of allowed conformal motions and local chemical environments. Importantly, this is done without costly molecular dynamics simulations required by other AAN-related methods, which allows us to analyse large proteins and/or data sets. We have calculated the centrality of the residues belonging to 795 proteins. The results display a strong, negative correlation between residue centrality and the evolutionary rate. Furthermore, among residues with high closeness, those with low degree were particularly strongly conserved. Random walk simulations using the RGN were also successful in identifying allosteric residues in proteins involved in GPCR signalling. The dynamic function of these residues largely remain hidden in the traditional distance-cutoff construction technique. Despite being constructed from only the crystal structure, the results in this paper suggests that the RGN can identify residues that fulfil a dynamical function. PMID:27623708

  11. Insights into the fold organization of TIM barrel from interaction energy based structure networks.

    Science.gov (United States)

    Vijayabaskar, M S; Vishveshwara, Saraswathi

    2012-01-01

    There are many well-known examples of proteins with low sequence similarity, adopting the same structural fold. This aspect of sequence-structure relationship has been extensively studied both experimentally and theoretically, however with limited success. Most of the studies consider remote homology or "sequence conservation" as the basis for their understanding. Recently "interaction energy" based network formalism (Protein Energy Networks (PENs)) was developed to understand the determinants of protein structures. In this paper we have used these PENs to investigate the common non-covalent interactions and their collective features which stabilize the TIM barrel fold. We have also developed a method of aligning PENs in order to understand the spatial conservation of interactions in the fold. We have identified key common interactions responsible for the conservation of the TIM fold, despite high sequence dissimilarity. For instance, the central beta barrel of the TIM fold is stabilized by long-range high energy electrostatic interactions and low-energy contiguous vdW interactions in certain families. The other interfaces like the helix-sheet or the helix-helix seem to be devoid of any high energy conserved interactions. Conserved interactions in the loop regions around the catalytic site of the TIM fold have also been identified, pointing out their significance in both structural and functional evolution. Based on these investigations, we have developed a novel network based phylogenetic analysis for remote homologues, which can perform better than sequence based phylogeny. Such an analysis is more meaningful from both structural and functional evolutionary perspective. We believe that the information obtained through the "interaction conservation" viewpoint and the subsequently developed method of structure network alignment, can shed new light in the fields of fold organization and de novo computational protein design.

  12. Conservative treatment of perforated upper gastrointestinal tract

    International Nuclear Information System (INIS)

    Naoi, Daishi; Sano, Wataru; Nakata, Yasuyuki; Yano, Kentaro; Suzuki, Takeshi; Chiku, Tsuyoshi; Tashiro, Tsuguhiko

    2009-01-01

    In order to clarify the validity of indication criteria of the conservative treatment for perforated upper gastrointestinal tract, a retrospective study was carried out. We enrolled 28 patients with perforation of the gastrointestinal tract who were determined to receive conservative treatment at the time of hospitalization from January 2000 to December 2007. When the following criteria were satisfied, we treated the patients by the conservative treatment after informed consent was gained from them and their families: stable condition of vital signs; peritoneal signs localized in the upper abdomen; and no or slight fluid collection at the Douglas' pouch determined by computed tomography. Patients who showed changes for the worse of peritonitis or increased fluid collection during follow-up were promptly converted to surgery. Six patients were converted to surgery, but all of them were discharged very much improved. We compared patient's data of the conservative treatment group and the converted surgery group at the time of consultation. All data were not statistically different between two groups. If all criteria are satisfied, it seemed that we can start conservative treatment for perforated gastrointestinal tract with careful observation and the system of prompt conversion to operation for patients who showed changes for the worse of peritonitis or increased fluid collection. (author)

  13. A Performance Analytical Strategy for Network-on-Chip Router with Input Buffer Architecture

    Directory of Open Access Journals (Sweden)

    WANG, J.

    2012-11-01

    Full Text Available In this paper, a performance analytical strategy is proposed for Network-on-Chip router with input buffer architecture. First, an analytical model is developed based on semi-Markov process. For the non-work-conserving router with small buffer size, the model can be used to analyze the schedule delay and the average service time for each buffer when given the related parameters. Then, the packet average delay in router is calculated by using the model. Finally, we validate the effectiveness of our strategy by simulation. By comparing our analytical results to simulation results, we show that our strategy successfully captures the Network-on-Chip router performance and it performs better than the state-of-art technology. Therefore, our strategy can be used as an efficiency performance analytical tool for Network-on-Chip design.

  14. Interacting Social and Environmental Predictors for the Spatial Distribution of Conservation Lands

    Science.gov (United States)

    Baldwin, Robert F.; Leonard, Paul B.

    2015-01-01

    Conservation decisions should be evaluated for how they meet conservation goals at multiple spatial extents. Conservation easements are land use decisions resulting from a combination of social and environmental conditions. An emerging area of research is the evaluation of spatial distribution of easements and their spatial correlates. We tested the relative influence of interacting social and environmental variables on the spatial distribution of conservation easements by ownership category and conservation status. For the Appalachian region of the United States, an area with a long history of human occupation and complex land uses including public-private conservation, we found that settlement, economic, topographic, and environmental data associated with spatial distribution of easements (N = 4813). Compared to random locations, easements were more likely to be found in lower elevations, in areas of greater agricultural productivity, farther from public protected areas, and nearer other human features. Analysis of ownership and conservation status revealed sources of variation, with important differences between local and state government ownerships relative to non-governmental organizations (NGOs), and among U.S. Geological Survey (USGS) GAP program status levels. NGOs were more likely to have easements nearer protected areas, and higher conservation status, while local governments held easements closer to settlement, and on lands of greater agricultural potential. Logistic interactions revealed environmental variables having effects modified by social correlates, and the strongest predictors overall were social (distance to urban area, median household income, housing density, distance to land trust office). Spatial distribution of conservation lands may be affected by geographic area of influence of conservation groups, suggesting that multi-scale conservation planning strategies may be necessary to satisfy local and regional needs for reserve networks. Our

  15. Interacting Social and Environmental Predictors for the Spatial Distribution of Conservation Lands.

    Science.gov (United States)

    Baldwin, Robert F; Leonard, Paul B

    2015-01-01

    Conservation decisions should be evaluated for how they meet conservation goals at multiple spatial extents. Conservation easements are land use decisions resulting from a combination of social and environmental conditions. An emerging area of research is the evaluation of spatial distribution of easements and their spatial correlates. We tested the relative influence of interacting social and environmental variables on the spatial distribution of conservation easements by ownership category and conservation status. For the Appalachian region of the United States, an area with a long history of human occupation and complex land uses including public-private conservation, we found that settlement, economic, topographic, and environmental data associated with spatial distribution of easements (N = 4813). Compared to random locations, easements were more likely to be found in lower elevations, in areas of greater agricultural productivity, farther from public protected areas, and nearer other human features. Analysis of ownership and conservation status revealed sources of variation, with important differences between local and state government ownerships relative to non-governmental organizations (NGOs), and among U.S. Geological Survey (USGS) GAP program status levels. NGOs were more likely to have easements nearer protected areas, and higher conservation status, while local governments held easements closer to settlement, and on lands of greater agricultural potential. Logistic interactions revealed environmental variables having effects modified by social correlates, and the strongest predictors overall were social (distance to urban area, median household income, housing density, distance to land trust office). Spatial distribution of conservation lands may be affected by geographic area of influence of conservation groups, suggesting that multi-scale conservation planning strategies may be necessary to satisfy local and regional needs for reserve networks. Our

  16. Being relevant: Practical guidance for early career researchers interested in solving conservation problems

    Directory of Open Access Journals (Sweden)

    J.M. Chapman

    2015-07-01

    Full Text Available In a human-altered world where biodiversity is in decline and conservation problems abound, there is a dire need to ensure that the next generation of conservation scientists have the knowledge, skills, and training to address these problems. So called “early career researchers” (ECRs in conservation science have many challenges before them and it is clear that the status quo must change to bridge the knowledge–action divide. Here we identify thirteen practical strategies that ECRs can employ to become more relevant. In this context, “relevance” refers to the ability to contribute to solving conservation problems through engagement with practitioners, policy makers, and stakeholders. Conservation and career strategies outlined in this article include the following: thinking ‘big picture’ during conservation projects; embracing various forms of knowledge; maintaining positive relationships with locals familiar with the conservation issue; accepting failure as a viable (and potentially valuable outcome; daring to be creative; embracing citizen science; incorporating interdisciplinarity; promoting and practicing pro-environmental behaviours; understanding financial aspects of conservation; forming collaboration from the onset of a project; accepting the limits of technology; ongoing and effective networking; and finally, maintaining a positive outlook by focusing on and sharing conservation success stories. These strategies move beyond the generic and highlight the importance of continuing to have an open mind throughout the entire conservation process, from establishing one’s self as an asset to embracing collaboration and interdisciplinary work, and striving to push for professional and personal connections that strengthen personal career objectives.

  17. Liberals think more analytically (more "WEIRD") than conservatives.

    Science.gov (United States)

    Talhelm, Thomas; Haidt, Jonathan; Oishi, Shigehiro; Zhang, Xuemin; Miao, Felicity F; Chen, Shimin

    2015-02-01

    Henrich, Heine, and Norenzayan summarized cultural differences in psychology and argued that people from one particular culture are outliers: people from societies that are Western, educated, industrialized, rich, and democratic (WEIRD). This study shows that liberals think WEIRDer than conservatives. In five studies with more than 5,000 participants, we found that liberals think more analytically (an element of WEIRD thought) than moderates and conservatives. Study 3 replicates this finding in the very different political culture of China, although it held only for people in more modernized urban centers. These results suggest that liberals and conservatives in the same country think as if they were from different cultures. Studies 4 to 5 show that briefly training people to think analytically causes them to form more liberal opinions, whereas training them to think holistically causes shifts to more conservative opinions. © 2014 by the Society for Personality and Social Psychology, Inc.

  18. Impacts of the Conservation Education Program in Serra Malagueta Natural Park, Cape Verde

    Science.gov (United States)

    Burnett, Edmund; Sills, Erin; Peterson, M. Nils; DePerno, Christopher

    2016-01-01

    Environmental and conservation education programs are commonly offered in the rapidly expanding network of protected areas in developing countries. There have been few evaluations of these programs and their impacts on participants. At Serra Malagueta Natural Park in Cape Verde, we assessed changes in environmental knowledge, opinions, and…

  19. Conservation laws in the quantum mechanics of closed systems

    International Nuclear Information System (INIS)

    Hartle, J.B.; Laflamme, R.; Marolf, D.

    1995-01-01

    We investigate conservation laws in the quantum mechanics of closed systems and begin by reviewing an argument that exact decoherence implies the exact conservation of quantities that commute with the Hamiltonian. However, we also show that decoherence limits the alternatives that can be included in sets of histories that assess the conservation of these quantities. In the case of charge and energy, these limitations would be severe were these quantities not coupled to a gauge field. However, for the realistic cases of electric charge coupled to the electromagnetic field and mass coupled to spacetime curvature, we show that when alternative values of charge and mass decohere they always decohere exactly and are exactly conserved. Further, while decohering histories that describe possible changes in time of the total charge and mass are also subject to the limitations mentioned above, we show that these do not, in fact, restrict physical alternatives and are therefore not really limitations at all

  20. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago Vanderlei; Giannitsarou, Chrysi; Johnson, CR

    2017-01-01

    We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and define a network aggregator that preserves network cohesion.

  1. Preferred conservation policies of shark researchers.

    Science.gov (United States)

    Shiffman, David S; Hammerschlag, Neil

    2016-08-01

    There is increasing concern about the conservation status of sharks. However, the presence of numerous different (and potentially mutually exclusive) policies complicates management implementation and public understanding of the process. We distributed an online survey to members of the largest professional shark and ray research societies to assess member knowledge of and attitudes toward different conservation policies. Questions covered society member opinions on conservation and management policies, personal histories of involvement in advocacy and management, and perceptions of the approach of conservation nongovernmental organizations (NGOs) to shark conservation. One hundred and two surveys were completed (overall response rate 21%). Respondents considered themselves knowledgeable about and actively involved in conservation and management policy; a majority believed scientists have a responsibility to advocate for conservation (75%), and majorities have sent formal public comments to policymakers (54%) and included policy suggestions in their papers (53%). They believe sustainable shark fisheries are possible, are currently happening today (in a few places), and should be the goal instead of banning fisheries. Respondents were generally less supportive of newer limit-based (i.e., policies that ban exploitation entirely without a species-specific focus) conservation policy tools, such as shark sanctuaries and bans on the sale of shark fins, than of target-based fisheries management tools (i.e., policies that allow for sustainable harvest of species whose populations can withstand it), such as fishing quotas. Respondents were generally supportive of environmental NGO efforts to conserve sharks but raised concerns about some NGOs that they perceived as using incorrect information and focusing on the wrong problems. Our results show there is an ongoing debate in shark conservation and management circles relative to environmental policy on target-based natural

  2. Which energy networks for tomorrow?

    International Nuclear Information System (INIS)

    Lenoir, D.; Couturier, Ch.; Batot, Ph.; Jedliczka, M.; Belon, D.; Goy, E.; Bureau, L.

    2010-01-01

    A set of brief articles outlines the importance of energy networks of all kinds for the future of energy conservation. Thus, all networks (communication, data, production command and control) will have a role to play to make all energy networks (electricity, gas, heat, cold, water, sewage, telecommunications) communicate with each other, and a new consumption/production model will have to be developed for each territory by taking into account its capacities to improve energy efficiency and valorize renewable energies. The authors also propose a historical perspective of network development and of their trend to become interconnected and complementary, comment the governance issue in terms of concession, evoke the supply of public networks with biogas (legal framework under development), discuss the value of the project of development of smart grids, suggest that a better electricity demand management could be an efficient alternative to grid development, comment the context and implications of the European directive Linky, outline that heat networks will contribute to the reduction of the environmental impact of buildings, evoke the issue of cold water networks and their impact on air conditioning, present the original heat network which is about to be built in Saint-Brieuc, etc.

  3. Standard representation and unified stability analysis for dynamic artificial neural network models.

    Science.gov (United States)

    Kim, Kwang-Ki K; Patrón, Ernesto Ríos; Braatz, Richard D

    2018-02-01

    An overview is provided of dynamic artificial neural network models (DANNs) for nonlinear dynamical system identification and control problems, and convex stability conditions are proposed that are less conservative than past results. The three most popular classes of dynamic artificial neural network models are described, with their mathematical representations and architectures followed by transformations based on their block diagrams that are convenient for stability and performance analyses. Classes of nonlinear dynamical systems that are universally approximated by such models are characterized, which include rigorous upper bounds on the approximation errors. A unified framework and linear matrix inequality-based stability conditions are described for different classes of dynamic artificial neural network models that take additional information into account such as local slope restrictions and whether the nonlinearities within the DANNs are odd. A theoretical example shows reduced conservatism obtained by the conditions. Copyright © 2017. Published by Elsevier Ltd.

  4. Looking for chemical reaction networks exhibiting a drift along a manifold of marginally stable states.

    Science.gov (United States)

    Brogioli, Doriano

    2013-02-07

    I recently reported some examples of mass-action equations that have a continuous manifold of marginally stable stationary states [Brogioli, D., 2010. Marginally stable chemical systems as precursors of life. Phys. Rev. Lett. 105, 058102; Brogioli, D., 2011. Marginal stability in chemical systems and its relevance in the origin of life. Phys. Rev. E 84, 031931]. The corresponding chemical reaction networks show nonclassical effects, i.e. a violation of the mass-action equations, under the effect of the concentration fluctuations: the chemical system drifts along the marginally stable states. I proposed that this effect is potentially involved in abiogenesis. In the present paper, I analyze the mathematical properties of mass-action equations of marginally stable chemical reaction networks. The marginal stability implies that the mass-action equations obey some conservation law; I show that the mathematical properties of the conserved quantity characterize the motion along the marginally stable stationary state manifold, i.e. they allow to predict if the fluctuations give rise to a random walk or a drift under the effect of concentration fluctuations. Moreover, I show that the presence of the drift along the manifold of marginally stable stationary-states is a critical property, i.e. at least one of the reaction constants must be fine tuned in order to obtain the drift. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Distributed topology control algorithm to conserve energy in heterogeneous wireless mesh networks

    CSIR Research Space (South Africa)

    Aron, FO

    2008-07-01

    Full Text Available in performance with the resulting topology being a sub-network of the one generated by [11]. Li and Halpern [13] further propose the small minimum energy communication network (SMECN). In this algorithm, each node u initially broadcasts a “hello” message... algorithm that runs in each node is presented as follows:- Phase1: Establishing the accessible neighbourhood topology. In this stage, node u broadcasts a “hello” message using its full power, max uP . The nodes that receive the “hello” message form...

  6. The Colorado Plateau V: research, environmental planning, and management for collaborative conservation

    Science.gov (United States)

    Villarreal, Miguel L.; van Riper, Carena J.; Johnson, Matthew J.; van Riper, Charles

    2012-01-01

    Roughly centered on the Four Corners region of the southwestern United States, the Colorado Plateau covers some 130,000 square miles of sparsely vegetated plateaus, mesas, canyons, arches, and cliffs in Arizona, Utah, Colorado, and New Mexico. With elevations ranging from 3,000 to 14,000 feet, the natural systems found within the plateau are dramatically varied, from desert to alpine conditions. This volume, the fifth from the University of Arizona Press and the tenth overall, focuses on adaptation of resource management and conservation to climate change and water scarcity, protecting biodiversity through restructured energy policies, ensuring wildlife habitat connectivity across barriers, building effective conservation networks, and exploring new opportunities for education and leadership in conservation science. An informative read for people interested in the conservation and natural history of the region, the book will also serve as a valuable reference for those people engaged in the management of cultural and biological resources of the Colorado Plateau, as well as scientists interested in methods and tools for land and resource management throughout the West.

  7. A mathematical model for generating bipartite graphs and its application to protein networks

    International Nuclear Information System (INIS)

    Nacher, J C; Ochiai, T; Hayashida, M; Akutsu, T

    2009-01-01

    Complex systems arise in many different contexts from large communication systems and transportation infrastructures to molecular biology. Most of these systems can be organized into networks composed of nodes and interacting edges. Here, we present a theoretical model that constructs bipartite networks with the particular feature that the degree distribution can be tuned depending on the probability rate of fundamental processes. We then use this model to investigate protein-domain networks. A protein can be composed of up to hundreds of domains. Each domain represents a conserved sequence segment with specific functional tasks. We analyze the distribution of domains in Homo sapiens and Arabidopsis thaliana organisms and the statistical analysis shows that while (a) the number of domain types shared by k proteins exhibits a power-law distribution, (b) the number of proteins composed of k types of domains decays as an exponential distribution. The proposed mathematical model generates bipartite graphs and predicts the emergence of this mixing of (a) power-law and (b) exponential distributions. Our theoretical and computational results show that this model requires (1) growth process and (2) copy mechanism.

  8. A mathematical model for generating bipartite graphs and its application to protein networks

    Science.gov (United States)

    Nacher, J. C.; Ochiai, T.; Hayashida, M.; Akutsu, T.

    2009-12-01

    Complex systems arise in many different contexts from large communication systems and transportation infrastructures to molecular biology. Most of these systems can be organized into networks composed of nodes and interacting edges. Here, we present a theoretical model that constructs bipartite networks with the particular feature that the degree distribution can be tuned depending on the probability rate of fundamental processes. We then use this model to investigate protein-domain networks. A protein can be composed of up to hundreds of domains. Each domain represents a conserved sequence segment with specific functional tasks. We analyze the distribution of domains in Homo sapiens and Arabidopsis thaliana organisms and the statistical analysis shows that while (a) the number of domain types shared by k proteins exhibits a power-law distribution, (b) the number of proteins composed of k types of domains decays as an exponential distribution. The proposed mathematical model generates bipartite graphs and predicts the emergence of this mixing of (a) power-law and (b) exponential distributions. Our theoretical and computational results show that this model requires (1) growth process and (2) copy mechanism.

  9. A mathematical model for generating bipartite graphs and its application to protein networks

    Energy Technology Data Exchange (ETDEWEB)

    Nacher, J C [Department of Complex Systems, Future University-Hakodate (Japan); Ochiai, T [Faculty of Engineering, Toyama Prefectural University (Japan); Hayashida, M; Akutsu, T [Bioinformatics Center, Institute for Chemical Research, Kyoto University (Japan)

    2009-12-04

    Complex systems arise in many different contexts from large communication systems and transportation infrastructures to molecular biology. Most of these systems can be organized into networks composed of nodes and interacting edges. Here, we present a theoretical model that constructs bipartite networks with the particular feature that the degree distribution can be tuned depending on the probability rate of fundamental processes. We then use this model to investigate protein-domain networks. A protein can be composed of up to hundreds of domains. Each domain represents a conserved sequence segment with specific functional tasks. We analyze the distribution of domains in Homo sapiens and Arabidopsis thaliana organisms and the statistical analysis shows that while (a) the number of domain types shared by k proteins exhibits a power-law distribution, (b) the number of proteins composed of k types of domains decays as an exponential distribution. The proposed mathematical model generates bipartite graphs and predicts the emergence of this mixing of (a) power-law and (b) exponential distributions. Our theoretical and computational results show that this model requires (1) growth process and (2) copy mechanism.

  10. Delta-Flux: An eddy covariance network for a climate-smart Lower Mississippi Basin

    Science.gov (United States)

    Runkle, Benjamin R. K.; Rigby, James R.; Reba, Michele L.; Anapalli, Saseendran S.; Bhattacharjee, Joydeep; Krauss, Ken W.; Liang, Lu; Locke, Martin A.; Novick, Kimberly A.; Sui, Ruixiu; Suvočarev, Kosana; White, Paul M.

    2017-01-01

    Networks of remotely monitored research sites are increasingly the tool used to study regional agricultural impacts on carbon and water fluxes. However, key national networks such as the National Ecological Observatory Network and AmeriFlux lack contributions from the Lower Mississippi River Basin (LMRB), a highly productive agricultural area with opportunities for soil carbon sequestration through conservation practices. The authors describe the rationale to create the new Delta-Flux network, which will coordinate efforts to quantify carbon and water budgets at seventeen eddy covariance flux tower sites in the LMRB. The network structure will facilitate climate-smart management strategies based on production-scale and continuous measurements of carbon and water fluxes from the landscape to the atmosphere under different soil and water management conditions. The seventeen instrumented field sites are expected to monitor fluxes within the most characteristic landscapes of the target area: row-crop fields, pasture, grasslands, forests, and marshes. The network participants are committed to open collaboration and efficient regionalization of site-level findings to support sustainable agricultural and forestry management and conservation of natural resources.

  11. The Push and Pull of Land Use Policy: Reconstructing 150 Years of Development and Conservation Land Acquisition

    Science.gov (United States)

    Santos, Maria João; Watt, Terry; Pincetl, Stephanie

    2014-01-01

    The growth of human populations and their resource needs have stressed the conservation of natural land resources. Many policies and programs have been implemented to address the pressures on land resources and notwithstanding this pressure, significant acquisition of land for conservation has occurred throughout history in the U.S., and internationally. Here we assess the on-the-ground result of the evolution of land use policies in California as a pioneer forerunner, in the form of acquisition of land for conservation (i.e. Open Space), and its impact on the rest of the U.S. and beyond. To this end we describe the timeline and spatial representation of the growth of California’s conservation network over the last 150 years, and link it to the history of land use policies. We then assess whether conservation land acquisition has consistently grown through time or occurred in specific decades. About ¼ of the state is now designated Open Space. Fewer and larger areas conserved and acquired at the beginning of the 20th century; the conservation network was complemented with a larger number of smaller sized properties. Despite acquisition of land in every decade, the process was uneven (E = 0.3 for California, E = 0.14±0.08 average for the state’s counties), mostly due to the large acquisitions and land set asides in the 1900s, followed by 1930s and 1940s. This process was a result of a comprehensive set of legislation that evolved through time, and resulted from the competing needs for development and conservation. Even with the impressive 174,000 km2 of public lands in California, the future of California’s natural infrastructure and natural heritage cannot rely solely on these public lands, nor public agencies and their resources. Critically a future course of land preservation relying on the purchase of new lands – in California and beyond – for conservation is tremendously expensive. PMID:25075611

  12. The Potential for Double-Loop Learning to Enable Landscape Conservation Efforts

    Science.gov (United States)

    Petersen, Brian; Montambault, Jensen; Koopman, Marni

    2014-10-01

    As conservation increases its emphasis on implementing change at landscape-level scales, multi-agency, cross-boundary, and multi-stakeholder networks become more important. These elements complicate traditional notions of learning. To investigate this further, we examined structures of learning in the Landscape Conservation Cooperatives (LCCs), which include the entire US and its territories, as well as parts of Canada, Mexico, and Caribbean and Pacific island states. We used semi-structured interviews, transcribed and analyzed using NVivo, as well as a charrette-style workshop to understand the difference between the original stated goals of individual LCCs and the values and purposes expressed as the collaboration matured. We suggest double-loop learning as a theoretical framework appropriate to landscape-scale conservation, recognizing that concerns about accountability are among the valid points of view that must be considered in multi-stakeholder collaborations. Methods from the social sciences and public health sectors provide insights on how such learning might be actualized.

  13. Loop 7 of E2 enzymes: an ancestral conserved functional motif involved in the E2-mediated steps of the ubiquitination cascade.

    Directory of Open Access Journals (Sweden)

    Elena Papaleo

    Full Text Available The ubiquitin (Ub system controls almost every aspect of eukaryotic cell biology. Protein ubiquitination depends on the sequential action of three classes of enzymes (E1, E2 and E3. E2 Ub-conjugating enzymes have a central role in the ubiquitination pathway, interacting with both E1 and E3, and influencing the ultimate fate of the substrates. Several E2s are characterized by an extended acidic insertion in loop 7 (L7, which if mutated is known to impair the proper E2-related functions. In the present contribution, we show that acidic loop is a conserved ancestral motif in E2s, relying on the presence of alternate hydrophobic and acidic residues. Moreover, the dynamic properties of a subset of family 3 E2s, as well as their binary and ternary complexes with Ub and the cognate E3, have been investigated. Here we provide a model of L7 role in the different steps of the ubiquitination cascade of family 3 E2s. The L7 hydrophobic residues turned out to be the main determinant for the stabilization of the E2 inactive conformations by a tight network of interactions in the catalytic cleft. Moreover, phosphorylation is known from previous studies to promote E2 competent conformations for Ub charging, inducing electrostatic repulsion and acting on the L7 acidic residues. Here we show that these active conformations are stabilized by a network of hydrophobic interactions between L7 and L4, the latter being a conserved interface for E3-recruitment in several E2s. In the successive steps, L7 conserved acidic residues also provide an interaction interface for both Ub and the Rbx1 RING subdomain of the cognate E3. Our data therefore suggest a crucial role for L7 of family 3 E2s in all the E2-mediated steps of the ubiquitination cascade. Its different functions are exploited thank to its conserved hydrophobic and acidic residues in a finely orchestrate mechanism.

  14. Heirloom biodynamic seeds network rescue, conservation and multiplication of local seeds in Brazil

    OpenAIRE

    Jovchelevich, Pedro

    2014-01-01

    Structuring a network organic and biodynamic seed involving farmers in the central- southern Brazil. Training, participatory breeding, edition of publications, fairs of exchange seeds, a processing unit and assessment of seed quality, commercial seed multiplication with emphasis on vegetables. This network has garanteed the autonomy of farmers in seed production and enriched agrobiodiversity through exchanges of seed.

  15. Large-scale Watershed Modeling: NHDPlus Resolution with Achievable Conservation Scenarios in the Western Lake Erie Basin

    Science.gov (United States)

    Yen, H.; White, M. J.; Arnold, J. G.; Keitzer, S. C.; Johnson, M. V. V.; Atwood, J. D.; Daggupati, P.; Herbert, M. E.; Sowa, S. P.; Ludsin, S.; Robertson, D. M.; Srinivasan, R.; Rewa, C. A.

    2016-12-01

    By the substantial improvement of computer technology, large-scale watershed modeling has become practically feasible in conducting detailed investigations of hydrologic, sediment, and nutrient processes. In the Western Lake Erie Basin (WLEB), water quality issues caused by anthropogenic activities are not just interesting research subjects but, have implications related to human health and welfare, as well as ecological integrity, resistance, and resilience. In this study, the Soil and Water Assessment Tool (SWAT) and the finest resolution stream network, NHDPlus, were implemented on the WLEB to examine the interactions between achievable conservation scenarios with corresponding additional projected costs. During the calibration/validation processes, both hard (temporal) and soft (non-temporal) data were used to ensure the modeling outputs are coherent with actual watershed behavior. The results showed that widespread adoption of conservation practices intended to provide erosion control could deliver average reductions of sediment and nutrients without additional nutrient management changes. On the other hand, responses of nitrate (NO3) and dissolved inorganic phosphorus (DIP) dynamics may be different than responses of total nitrogen and total phosphorus dynamics under the same conservation practice. Model results also implied that fewer financial resources are required to achieve conservation goals if the goal is to achieve reductions in targeted watershed outputs (ex. NO3 or DIP) rather than aggregated outputs (ex. total nitrogen or total phosphorus). In addition, it was found that the model's capacity to simulate seasonal effects and responses to changing conservation adoption on a seasonal basis could provide a useful index to help alleviate additional cost through temporal targeting of conservation practices. Scientists, engineers, and stakeholders can take advantage of the work performed in this study as essential information while conducting policy

  16. The Ribonucleoprotein Csr Network

    Directory of Open Access Journals (Sweden)

    Ethel Seyll

    2013-11-01

    Full Text Available Ribonucleoprotein complexes are essential regulatory components in bacteria. In this review, we focus on the carbon storage regulator (Csr network, which is well conserved in the bacterial world. This regulatory network is composed of the CsrA master regulator, its targets and regulators. CsrA binds to mRNA targets and regulates translation either negatively or positively. Binding to small non-coding RNAs controls activity of this protein. Expression of these regulators is tightly regulated at the level of transcription and stability by various global regulators (RNAses, two-component systems, alarmone. We discuss the implications of these complex regulations in bacterial adaptation.

  17. Temporal variation in bat-fruit interactions: Foraging strategies influence network structure over time

    Science.gov (United States)

    Zapata-Mesa, Natalya; Montoya-Bustamante, Sebastián; Murillo-García, Oscar E.

    2017-11-01

    Mutualistic interactions, such as seed dispersal, are important for the maintenance of structure and stability of tropical communities. However, there is a lack of information about spatial and temporal variation in plant-animal interaction networks. Thus, our goal was to assess the effect of bat's foraging strategies on temporal variation in the structure and robustness of bat-fruit networks in both a dry and a rain tropical forest. We evaluated monthly variation in bat-fruit networks by using seven structure metrics: network size, average path length, nestedness, modularity, complementary specialization, normalized degree and betweenness centrality. Seed dispersal networks showed variations in size, species composition and modularity; did not present nested structures and their complementary specialization was high compared to other studies. Both networks presented short path lengths, and a constantly high robustness, despite their monthly variations. Sedentary bat species were recorded during all the study periods and occupied more central positions than nomadic species. We conclude that foraging strategies are important structuring factors that affect the dynamic of networks by determining the functional roles of frugivorous bats over time; thus sedentary bats are more important than nomadic species for the maintenance of the network structure, and their conservation is a must.

  18. Community and conservation reserves in southern India: status, challenges and opportunities

    Directory of Open Access Journals (Sweden)

    A. Kanagavel

    2013-12-01

    Full Text Available Community Reserves and Conservation Reserves illustrate a community-based co-management model, a first of its kind within the protected area (PA network of India. Such reserves mark a shift towards an inclusive and decentralised approach within PAs in the country. Three such reserves in southern India: the Aghanashini Lion-tailed Macaque Conservation Reserve, Kadalundi-Vallikunnu Community Reserve and Thirupaddaimaradur Conservation Reserve, were selected to examine the reasons for their creation, management and stakeholder dynamics, with an aim to review their productivity and potential replicability. The study was carried out through semi-structured interviews with Forest Department officials, local community members and researchers working in the three reserves. Insufficient interaction between the stakeholders appeared to be a common issue in two reserves. The functioning of the reserves was also influenced, and in some cases negatively affected, by local politics. Financial stability was crucial in the functioning of reserves, as was consistency in interaction and appropriate monitoring of management plans. These elements are recommended for sustaining such reserves and creating community-based management systems for conservation, to support an inclusive approach to PA management.

  19. Is U.S. climatic diversity well represented within the existing federal protection network?

    Science.gov (United States)

    Enric Batllori; Carol Miller; Marc-Andre Parisien; Sean A. Parks; Max A. Moritz

    2014-01-01

    Establishing protection networks to ensure that biodiversity and associated ecosystem services persist under changing environments is a major challenge for conservation planning. The potential consequences of altered climates for the structure and function of ecosystems necessitates new and complementary approaches be incorporated into traditional conservation plans....

  20. Estimating energy conservation patterns of Greek households

    International Nuclear Information System (INIS)

    Sardianou, Eleni

    2007-01-01

    This paper develops an empirical model to investigate the main determinants of household energy conservation patterns in Greece employing cross-section data. In the empirical analysis, household energy-conserving choices models are employed, using a discrete and a latent trait variable respectively as a dependent variable. The results show that socio-economic variables such as consumers' income and family size are suitable to explain differences towards energy conservation preferences. In addition, the results suggest that electricity expenditures and age of the respondent are negatively associated with the number of energy-conserving actions that a consumer is willing to adopt. Finally, other variables such as environmental information feedback and consciousness of energy problems are characteristics of the energy-saver consumer. By evaluating consumer's decision-making process with regards to energy conservation measures, we are able to formulate and propose an effective energy conservation framework for Greece. An energy policy framework is among the main prerequisites not only to achieve sustainable development but also to maintain consumers' quality of life

  1. AlignNemo: a local network alignment method to integrate homology and topology.

    Directory of Open Access Journals (Sweden)

    Giovanni Ciriello

    Full Text Available Local network alignment is an important component of the analysis of protein-protein interaction networks that may lead to the identification of evolutionary related complexes. We present AlignNemo, a new algorithm that, given the networks of two organisms, uncovers subnetworks of proteins that relate in biological function and topology of interactions. The discovered conserved subnetworks have a general topology and need not to correspond to specific interaction patterns, so that they more closely fit the models of functional complexes proposed in the literature. The algorithm is able to handle sparse interaction data with an expansion process that at each step explores the local topology of the networks beyond the proteins directly interacting with the current solution. To assess the performance of AlignNemo, we ran a series of benchmarks using statistical measures as well as biological knowledge. Based on reference datasets of protein complexes, AlignNemo shows better performance than other methods in terms of both precision and recall. We show our solutions to be biologically sound using the concept of semantic similarity applied to Gene Ontology vocabularies. The binaries of AlignNemo and supplementary details about the algorithms and the experiments are available at: sourceforge.net/p/alignnemo.

  2. Comparative mtDNA analyses of three sympatric macropodids from a conservation area on the Huon Peninsula, Papua New Guinea.

    Science.gov (United States)

    McGreevy, Thomas J; Dabek, Lisa; Husband, Thomas P

    2016-07-01

    Matschie's tree kangaroo (Dendrolagus matschiei), New Guinea pademelon (Thylogale browni), and small dorcopsis (Dorcopsulus vanheurni) are sympatric macropodid taxa, of conservation concern, that inhabit the Yopno-Urawa-Som (YUS) Conservation Area on the Huon Peninsula, Papua New Guinea. We sequenced three partial mitochondrial DNA (mtDNA) genes from the three taxa to (i) investigate network structure; and (ii) identify conservation units within the YUS Conservation Area. All three taxa displayed a similar pattern in the spatial distribution of their mtDNA haplotypes and the Urawa and Som rivers on the Huon may have acted as a barrier to maternal gene flow. Matschie's tree kangaroo and New Guinea pademelon within the YUS Conservation Area should be managed as single conservation units because mtDNA nucleotides were not fixed for a given geographic area. However, two distinct conservation units were identified for small dorcopsis from the two different mountain ranges within the YUS Conservation Area.

  3. Conservation reaches new heights.

    Science.gov (United States)

    Pepall, J; Khanal, P

    1992-10-01

    The conservation program with the management assistance of the Woodlands Mountain Institute in 2 contiguous parks, the Mount Everest National Park in Nepal and the Qomolangma Nature Reserve in China, in 2 countries is described. The focus is on conservation of the complex ecosystem with sustainable development by showing local people how to benefit from the park without environmental damage. Cultural diversity is as important as biological diversity. The area has been designated by UNESCO as a World Heritage Site with the "last pure ecological seed" of the Himalayas. The regional geography and culture are presented. Population growth has impacted natural resources through overgrazing, cultivation of marginal land, and deforestation; future plans to build a dam and road bordering the nature reserve pose other threats. Proposed management plans for the Makalu-Barun Nature Park (established in November 1991) and Conservation Area include a division of the park into nature reserve areas free of human activity, protected areas which permit traditional land use, and special sites and trail for tourists and religious pilgrims. The conservation area will act as a buffer for the park and provide economic opportunities; further subdivisions include land use for biodiversity protection, community forest and pasture, agroforestry, and agriculture and settlement. Efforts will be made to increase the welfare of women and local people; proposed projects include the introduction of higher milk-producing animals for stall feeding. Also proposed is a cultural and natural history museum. 70% of the project's resources will be directed to local community participation in consultation and park maintenance. The project is a model of how conservation and protection of natural resources can coexist with local economic development and participation; an integration of preservation of biological diversity, mountain wisdom, and the value of local people as resources for conservation.

  4. Network evolution by nonlinear preferential rewiring of edges

    Science.gov (United States)

    Xu, Xin-Jian; Hu, Xiao-Ming; Zhang, Li-Jie

    2011-06-01

    The mathematical framework for small-world networks proposed in a seminal paper by Watts and Strogatz sparked a widespread interest in modeling complex networks in the past decade. However, most of research contributing to static models is in contrast to real-world dynamic networks, such as social and biological networks, which are characterized by rearrangements of connections among agents. In this paper, we study dynamic networks evolved by nonlinear preferential rewiring of edges. The total numbers of vertices and edges of the network are conserved, but edges are continuously rewired according to the nonlinear preference. Assuming power-law kernels with exponents α and β, the network structures in stationary states display a distinct behavior, depending only on β. For β>1, the network is highly heterogeneous with the emergence of starlike structures. For β<1, the network is widely homogeneous with a typical connectivity. At β=1, the network is scale free with an exponential cutoff.

  5. Using circuit theory to model connectivity in ecology, evolution, and conservation.

    Science.gov (United States)

    McRae, Brad H; Dickson, Brett G; Keitt, Timothy H; Shah, Viral B

    2008-10-01

    Connectivity among populations and habitats is important for a wide range of ecological processes. Understanding, preserving, and restoring connectivity in complex landscapes requires connectivity models and metrics that are reliable, efficient, and process based. We introduce a new class of ecological connectivity models based in electrical circuit theory. Although they have been applied in other disciplines, circuit-theoretic connectivity models are new to ecology. They offer distinct advantages over common analytic connectivity models, including a theoretical basis in random walk theory and an ability to evaluate contributions of multiple dispersal pathways. Resistance, current, and voltage calculated across graphs or raster grids can be related to ecological processes (such as individual movement and gene flow) that occur across large population networks or landscapes. Efficient algorithms can quickly solve networks with millions of nodes, or landscapes with millions of raster cells. Here we review basic circuit theory, discuss relationships between circuit and random walk theories, and describe applications in ecology, evolution, and conservation. We provide examples of how circuit models can be used to predict movement patterns and fates of random walkers in complex landscapes and to identify important habitat patches and movement corridors for conservation planning.

  6. Exploring the bZIP transcription factor regulatory network in Neurospora crassa.

    Science.gov (United States)

    Tian, Chaoguang; Li, Jingyi; Glass, N Louise

    2011-03-01

    Transcription factors (TFs) are key nodes of regulatory networks in eukaryotic organisms, including filamentous fungi such as Neurospora crassa. The 178 predicted DNA-binding TFs in N. crassa are distributed primarily among six gene families, which represent an ancient expansion in filamentous ascomycete genomes; 98 TF genes show detectable expression levels during vegetative growth of N. crassa, including 35 that show a significant difference in expression level between hyphae at the periphery versus hyphae in the interior of a colony. Regulatory networks within a species genome include paralogous TFs and their respective target genes (TF regulon). To investigate TF network evolution in N. crassa, we focused on the basic leucine zipper (bZIP) TF family, which contains nine members. We performed baseline transcriptional profiling during vegetative growth of the wild-type and seven isogenic, viable bZIP deletion mutants. We further characterized the regulatory network of one member of the bZIP family, NCU03905. NCU03905 encodes an Ap1-like protein (NcAp-1), which is involved in resistance to multiple stress responses, including oxidative and heavy metal stress. Relocalization of NcAp-1 from the cytoplasm to the nucleus was associated with exposure to stress. A comparison of the NcAp-1 regulon with Ap1-like regulons in Saccharomyces cerevisiae, Schizosaccharomyces pombe, Candida albicans and Aspergillus fumigatus showed both conservation and divergence. These data indicate how N. crassa responds to stress and provide information on pathway evolution.

  7. Truncated Wigner dynamics and conservation laws

    Science.gov (United States)

    Drummond, Peter D.; Opanchuk, Bogdan

    2017-10-01

    Ultracold Bose gases can be used to experimentally test many-body theory predictions. Here we point out that both exact conservation laws and dynamical invariants exist in the topical case of the one-dimensional Bose gas, and these provide an important validation of methods. We show that the first four quantum conservation laws are exactly conserved in the approximate truncated Wigner approach to many-body quantum dynamics. Center-of-mass position variance is also exactly calculable. This is nearly exact in the truncated Wigner approximation, apart from small terms that vanish as N-3 /2 as N →∞ with fixed momentum cutoff. Examples of this are calculated in experimentally relevant, mesoscopic cases.

  8. The building network energy statistics 2002[Norway]; Bygningsnettverkets energistatistikk 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The report surveys a Norwegian network within the construction business and the energy utilization particularly in various buildings. There are sections on the network structure, the energy use in 2002, the building aspects and various project types. The emphasis is on energy conservation aspects. Various technologies and energy systems as well as building types, are discussed. (tk)

  9. A graduate education framework for tropical conservation and development.

    Science.gov (United States)

    Kainer, Karen A; Schmink, Marianne; Covert, Hannah; Stepp, John Richard; Bruna, Emilio M; Dain, Jonathan L; Espinosa, Santiago; Humphries, Shoana

    2006-02-01

    emphasize learning and action networks of students, faculty, and field partners, provide the best hope for responding to the emerging challenges of tropical conservation and development.

  10. Fenced and Fragmented: Conservation Value of Managed Metapopulations

    Science.gov (United States)

    Miller, Susan M.; Harper, Cindy K.; Bloomer, Paulette; Hofmeyr, Jennifer; Funston, Paul J.

    2015-01-01

    Population fragmentation is threatening biodiversity worldwide. Species that once roamed vast areas are increasingly being conserved in small, isolated areas. Modern management approaches must adapt to ensure the continued survival and conservation value of these populations. In South Africa, a managed metapopulation approach has been adopted for several large carnivore species, all protected in isolated, relatively small, reserves that are fenced. As far as possible these approaches are based on natural metapopulation structures. In this network, over the past 25 years, African lions (Panthera leo) were reintroduced into 44 fenced reserves with little attention given to maintaining genetic diversity. To examine the situation, we investigated the current genetic provenance and diversity of these lions. We found that overall genetic diversity was similar to that in a large national park, and included a mixture of four different southern African evolutionarily significant units (ESUs). This mixing of ESUs, while not ideal, provides a unique opportunity to study the impact of mixing ESUs over the long term. We propose a strategic managed metapopulation plan to ensure the maintenance of genetic diversity and improve the long-term conservation value of these lions. This managed metapopulation approach could be applied to other species under similar ecological constraints around the globe. PMID:26699333

  11. Reviewing Biosphere Reserves globally: effective conservation action or bureaucratic label?

    Science.gov (United States)

    Coetzer, Kaera L; Witkowski, Edward T F; Erasmus, Barend F N

    2014-02-01

    The Biosphere Reserve (BR) model of UNESCO's Man and the Biosphere Programme reflects a shift towards more accountable conservation. Biosphere Reserves attempt to reconcile environmental protection with sustainable development; they explicitly acknowledge humans, and human interests in the conservation landscape while still maintaining the ecological values of existing protected areas. Conceptually, this model is attractive, with 610 sites currently designated globally. Yet the practical reality of implementing dual 'conservation' and 'development' goals is challenging, with few examples successfully conforming to the model's full criteria. Here, we review the history of Biosphere Reserves from first inception in 1974 to the current status quo, and examine the suitability of the designation as an effective conservation model. We track the spatial expansion of Biosphere Reserves globally, assessing the influence of the Statutory Framework of the World Network of Biosphere Reserves and Seville strategy in 1995, when the BR concept refocused its core objectives on sustainable development. We use a comprehensive range of case studies to discuss conformity to the Programme, the social and ecological consequences associated with implementation of the designation, and challenges in aligning conservation and development. Given that the 'Biosphere Reserve' label is a relatively unknown designation in the public arena, this review also provides details on popularising the Biosphere Reserve brand, as well as prospects for further research, currently unexploited, but implicit in the designation. © 2013 The Authors. Biological Reviews © 2013 Cambridge Philosophical Society.

  12. Conservation Compromises: The MAB and the Legacy of the International Biological Program, 1964-1974.

    Science.gov (United States)

    Schleper, Simone

    2017-02-01

    This article looks at the International Biological Program (IBP) as the predecessor of UNESCO's well-known and highly successful Man and the Biosphere Programme (MAB). It argues that international conservation efforts of the 1970s, such as the MAB, must in fact be understood as a compound of two opposing attempts to reform international conservation in the 1960s. The scientific framework of the MAB has its origins in disputes between high-level conservationists affiliated with the International Union for the Conservation of Nature and Natural Resources (IUCN) about what the IBP meant for the future of conservation. Their respective visions entailed different ecological philosophies as much as diverging sets of political ideologies regarding the global implementation of conservation. Within the IBP's Conservation Section, one group propagated a universal systems approach to conservation with a centralized, technocratic management of nature and society by an elite group of independent scientific experts. Within IUCN, a second group based their notion of environmental expert roles on a more descriptive and local ecology of resource mapping as practiced by UNESCO. When the IBP came to an end in 1974, both groups' ecological philosophies played into the scientific framework underlying the MAB's World Network or Biosphere Reserves. The article argues that it is impossible to understand the course of conservation within the MAB without studying the dynamics and discourses between the two underlying expert groups and their respective visions for reforming conservation.

  13. A graph-theory framework for evaluating landscape connectivity and conservation planning.

    Science.gov (United States)

    Minor, Emily S; Urban, Dean L

    2008-04-01

    Connectivity of habitat patches is thought to be important for movement of genes, individuals, populations, and species over multiple temporal and spatial scales. We used graph theory to characterize multiple aspects of landscape connectivity in a habitat network in the North Carolina Piedmont (U.S.A). We compared this landscape with simulated networks with known topology, resistance to disturbance, and rate of movement. We introduced graph measures such as compartmentalization and clustering, which can be used to identify locations on the landscape that may be especially resilient to human development or areas that may be most suitable for conservation. Our analyses indicated that for songbirds the Piedmont habitat network was well connected. Furthermore, the habitat network had commonalities with planar networks, which exhibit slow movement, and scale-free networks, which are resistant to random disturbances. These results suggest that connectivity in the habitat network was high enough to prevent the negative consequences of isolation but not so high as to allow rapid spread of disease. Our graph-theory framework provided insight into regional and emergent global network properties in an intuitive and visual way and allowed us to make inferences about rates and paths of species movements and vulnerability to disturbance. This approach can be applied easily to assessing habitat connectivity in any fragmented or patchy landscape.

  14. 2nd East Africa Regional Workshop Report: Conservation Agriculture in AFRICA - Analysing and Foreseeing its Impact - Comprehending its Adoption

    OpenAIRE

    Apina, T.; Mkomwa, S.; Mutai, W.; Njeri, A.

    2011-01-01

    This resource provides a summary of the 2nd East Africa Sub-regional workshop held in Nanyuki, Kenya, on 28-30 March 2011. Attendees included the African Conservation Tillage Network (ACT), Tropical Soil Biology and Fertility Institute (TSBF/AFNET), Agricultural Research for Development (CIRAD), LEIBNIZ-Centre for Agricultural Landscape Research (ZALF), Agricultural Research Institute (ARI) UYOLE, SELIAN Agricultural Research Institute (SARI-MAFC), Conservation Agriculture for Sustainable Agr...

  15. Protecting Important Sites for Biodiversity Contributes to Meeting Global Conservation Targets

    Science.gov (United States)

    Butchart, Stuart H. M.; Scharlemann, Jörn P. W.; Evans, Mike I.; Quader, Suhel; Aricò, Salvatore; Arinaitwe, Julius; Balman, Mark; Bennun, Leon A.; Bertzky, Bastian; Besançon, Charles; Boucher, Timothy M.; Brooks, Thomas M.; Burfield, Ian J.; Burgess, Neil D.; Chan, Simba; Clay, Rob P.; Crosby, Mike J.; Davidson, Nicholas C.; De Silva, Naamal; Devenish, Christian; Dutson, Guy C. L.; Fernández, David F. Día z; Fishpool, Lincoln D. C.; Fitzgerald, Claire; Foster, Matt; Heath, Melanie F.; Hockings, Marc; Hoffmann, Michael; Knox, David; Larsen, Frank W.; Lamoreux, John F.; Loucks, Colby; May, Ian; Millett, James; Molloy, Dominic; Morling, Paul; Parr, Mike; Ricketts, Taylor H.; Seddon, Nathalie; Skolnik, Benjamin; Stuart, Simon N.; Upgren, Amy; Woodley, Stephen

    2012-01-01

    Protected areas (PAs) are a cornerstone of conservation efforts and now cover nearly 13% of the world's land surface, with the world's governments committed to expand this to 17%. However, as biodiversity continues to decline, the effectiveness of PAs in reducing the extinction risk of species remains largely untested. We analyzed PA coverage and trends in species' extinction risk at globally significant sites for conserving birds (10,993 Important Bird Areas, IBAs) and highly threatened vertebrates and conifers (588 Alliance for Zero Extinction sites, AZEs) (referred to collectively hereafter as ‘important sites’). Species occurring in important sites with greater PA coverage experienced smaller increases in extinction risk over recent decades: the increase was half as large for bird species with>50% of the IBAs at which they occur completely covered by PAs, and a third lower for birds, mammals and amphibians restricted to protected AZEs (compared with unprotected or partially protected sites). Globally, half of the important sites for biodiversity conservation remain unprotected (49% of IBAs, 51% of AZEs). While PA coverage of important sites has increased over time, the proportion of PA area covering important sites, as opposed to less important land, has declined (by 0.45–1.14% annually since 1950 for IBAs and 0.79–1.49% annually for AZEs). Thus, while appropriately located PAs may slow the rate at which species are driven towards extinction, recent PA network expansion has under-represented important sites. We conclude that better targeted expansion of PA networks would help to improve biodiversity trends. PMID:22457717

  16. Protecting important sites for biodiversity contributes to meeting global conservation targets.

    Directory of Open Access Journals (Sweden)

    Stuart H M Butchart

    Full Text Available Protected areas (PAs are a cornerstone of conservation efforts and now cover nearly 13% of the world's land surface, with the world's governments committed to expand this to 17%. However, as biodiversity continues to decline, the effectiveness of PAs in reducing the extinction risk of species remains largely untested. We analyzed PA coverage and trends in species' extinction risk at globally significant sites for conserving birds (10,993 Important Bird Areas, IBAs and highly threatened vertebrates and conifers (588 Alliance for Zero Extinction sites, AZEs (referred to collectively hereafter as 'important sites'. Species occurring in important sites with greater PA coverage experienced smaller increases in extinction risk over recent decades: the increase was half as large for bird species with>50% of the IBAs at which they occur completely covered by PAs, and a third lower for birds, mammals and amphibians restricted to protected AZEs (compared with unprotected or partially protected sites. Globally, half of the important sites for biodiversity conservation remain unprotected (49% of IBAs, 51% of AZEs. While PA coverage of important sites has increased over time, the proportion of PA area covering important sites, as opposed to less important land, has declined (by 0.45-1.14% annually since 1950 for IBAs and 0.79-1.49% annually for AZEs. Thus, while appropriately located PAs may slow the rate at which species are driven towards extinction, recent PA network expansion has under-represented important sites. We conclude that better targeted expansion of PA networks would help to improve biodiversity trends.

  17. Conservation of Endangered Species: What Do Children Think?

    Science.gov (United States)

    Ashworth, Sarah; And Others

    1995-01-01

    Describes results of questionnaire studies of children's ideas on which species most warrant conservation and why. When six animals meriting conservation were presented, children listed them in the following order: whale, panda, elephant, monkey, shark, and crocodile. The study showed that children tend to be most influenced toward the worthiness…

  18. Conserving agrobiodiversity amid global change, migration, and nontraditional livelihood networks: the dynamic uses of cultural landscape knowledge

    Directory of Open Access Journals (Sweden)

    Karl S. Zimmerer

    2014-06-01

    agrobiodiversity between 2006 and 2012 is shown to have occurred amid a transition toward the integral roles of multiple migration-related groups, namely women farmers, consumers, and local business owners; migrants; field caretakers; and local in-migrant laborers. The nontraditional social networks among these livelihood groups must be incorporated into analysis and planning of the design, participation, and monitoring of management and policy options for cultural landscapes ensuring the use, in situ conservation, and sustainability, including ecosystem services, of food plant landraces in global agrobiodiversity hot spots.

  19. The assembly and disassembly of ecological networks.

    Science.gov (United States)

    Bascompte, Jordi; Stouffer, Daniel B

    2009-06-27

    Global change has created a severe biodiversity crisis. Species are driven extinct at an increasing rate, and this has the potential to cause further coextinction cascades. The rate and shape of these coextinction cascades depend very much on the structure of the networks of interactions across species. Understanding network structure and how it relates to network disassembly, therefore, is a priority for system-level conservation biology. This process of network collapse may indeed be related to the process of network build-up, although very little is known about both processes and even less about their relationship. Here we review recent work that provides some preliminary answers to these questions. First, we focus on network assembly by emphasizing temporal processes at the species level, as well as the structural building blocks of complex ecological networks. Second, we focus on network disassembly as a consequence of species extinctions or habitat loss. We conclude by emphasizing some general rules of thumb that can help in building a comprehensive framework to understand the responses of ecological networks to global change.

  20. 77 FR 59712 - Energy Conservation Program: Energy Conservation Standards for Dishwashers

    Science.gov (United States)

    2012-10-01

    ... amended energy conservation standards, DOE conducted a market survey using all available public... Energy Conservation Program: Energy Conservation Standards for Dishwashers AGENCY: Office of Energy... establish amended energy conservation standards for dishwashers in the Federal Register on May 30, 2012. DOE...

  1. Improving the Conservation of Mediterranean Chondrichthyans: The ELASMOMED DNA Barcode Reference Library.

    Directory of Open Access Journals (Sweden)

    Alessia Cariani

    Full Text Available Cartilaginous fish are particularly vulnerable to anthropogenic stressors and environmental change because of their K-selected reproductive strategy. Accurate data from scientific surveys and landings are essential to assess conservation status and to develop robust protection and management plans. Currently available data are often incomplete or incorrect as a result of inaccurate species identifications, due to a high level of morphological stasis, especially among closely related taxa. Moreover, several diagnostic characters clearly visible in adult specimens are less evident in juveniles. Here we present results generated by the ELASMOMED Consortium, a regional network aiming to sample and DNA-barcode the Mediterranean Chondrichthyans with the ultimate goal to provide a comprehensive DNA barcode reference library. This library will support and improve the molecular taxonomy of this group and the effectiveness of management and conservation measures. We successfully barcoded 882 individuals belonging to 42 species (17 sharks, 24 batoids and one chimaera, including four endemic and several threatened ones. Morphological misidentifications were found across most orders, further confirming the need for a comprehensive DNA barcoding library as a valuable tool for the reliable identification of specimens in support of taxonomist who are reviewing current identification keys. Despite low intraspecific variation among their barcode sequences and reduced samples size, five species showed preliminary evidence of phylogeographic structure. Overall, the ELASMOMED initiative further emphasizes the key role accurate DNA barcoding libraries play in establishing reliable diagnostic species specific features in otherwise taxonomically problematic groups for biodiversity management and conservation actions.

  2. Domain architecture conservation in orthologs

    Science.gov (United States)

    2011-01-01

    Background As orthologous proteins are expected to retain function more often than other homologs, they are often used for functional annotation transfer between species. However, ortholog identification methods do not take into account changes in domain architecture, which are likely to modify a protein's function. By domain architecture we refer to the sequential arrangement of domains along a protein sequence. To assess the level of domain architecture conservation among orthologs, we carried out a large-scale study of such events between human and 40 other species spanning the entire evolutionary range. We designed a score to measure domain architecture similarity and used it to analyze differences in domain architecture conservation between orthologs and paralogs relative to the conservation of primary sequence. We also statistically characterized the extents of different types of domain swapping events across pairs of orthologs and paralogs. Results The analysis shows that orthologs exhibit greater domain architecture conservation than paralogous homologs, even when differences in average sequence divergence are compensated for, for homologs that have diverged beyond a certain threshold. We interpret this as an indication of a stronger selective pressure on orthologs than paralogs to retain the domain architecture required for the proteins to perform a specific function. In general, orthologs as well as the closest paralogous homologs have very similar domain architectures, even at large evolutionary separation. The most common domain architecture changes observed in both ortholog and paralog pairs involved insertion/deletion of new domains, while domain shuffling and segment duplication/deletion were very infrequent. Conclusions On the whole, our results support the hypothesis that function conservation between orthologs demands higher domain architecture conservation than other types of homologs, relative to primary sequence conservation. This supports the

  3. Discovery of intramolecular signal transduction network based on a new protein dynamics model of energy dissipation.

    Directory of Open Access Journals (Sweden)

    Cheng-Wei Ma

    Full Text Available A novel approach to reveal intramolecular signal transduction network is proposed in this work. To this end, a new algorithm of network construction is developed, which is based on a new protein dynamics model of energy dissipation. A key feature of this approach is that direction information is specified after inferring protein residue-residue interaction network involved in the process of signal transduction. This enables fundamental analysis of the regulation hierarchy and identification of regulation hubs of the signaling network. A well-studied allosteric enzyme, E. coli aspartokinase III, is used as a model system to demonstrate the new method. Comparison with experimental results shows that the new approach is able to predict all the sites that have been experimentally proved to desensitize allosteric regulation of the enzyme. In addition, the signal transduction network shows a clear preference for specific structural regions, secondary structural types and residue conservation. Occurrence of super-hubs in the network indicates that allosteric regulation tends to gather residues with high connection ability to collectively facilitate the signaling process. Furthermore, a new parameter of propagation coefficient is defined to determine the propagation capability of residues within a signal transduction network. In conclusion, the new approach is useful for fundamental understanding of the process of intramolecular signal transduction and thus has significant impact on rational design of novel allosteric proteins.

  4. A network of paralogous stress response transcription factors in the human pathogen Candida glabrata.

    Directory of Open Access Journals (Sweden)

    Jawad eMerhej

    2016-05-01

    Full Text Available The yeast Candida glabrata has become the second cause of systemic candidemia in humans. However, relatively few genome-wide studies have been conducted in this organism and our knowledge of its transcriptional regulatory network is quite limited. In the present work, we combined genome-wide chromatin immunoprecipitation (ChIP-seq, transcriptome analyses and DNA binding motif predictions to describe the regulatory interactions of the seven Yap (Yeast AP1 transcription factors of C. glabrata. We described a transcriptional network containing 255 regulatory interactions and 309 potential target genes. We predicted with high confidence the preferred DNA binding sites for 5 of the 7 CgYaps and showed a strong conservation of the Yap DNA binding properties between S. cerevisiae and C. glabrata. We provided reliable functional annotation for 3 of the 7 Yaps and identified for Yap1 and Yap5 a core regulon which is conserved in S. cerevisiae, C. glabrata and C. albicans. We uncovered new roles for CgYap7 in the regulation of iron-sulfur cluster biogenesis, for CgYap1 in the regulation of heme biosynthesis and for CgYap5 in the repression of GRX4 in response to iron starvation. These transcription factors define an interconnected transcriptional network at the cross-roads between redox homeostasis, oxygen consumption and iron metabolism.

  5. Phylogenetic diversity and biodiversity indices on phylogenetic networks.

    Science.gov (United States)

    Wicke, Kristina; Fischer, Mareike

    2018-04-01

    In biodiversity conservation it is often necessary to prioritize the species to conserve. Existing approaches to prioritization, e.g. the Fair Proportion Index and the Shapley Value, are based on phylogenetic trees and rank species according to their contribution to overall phylogenetic diversity. However, in many cases evolution is not treelike and thus, phylogenetic networks have been developed as a generalization of phylogenetic trees, allowing for the representation of non-treelike evolutionary events, such as hybridization. Here, we extend the concepts of phylogenetic diversity and phylogenetic diversity indices from phylogenetic trees to phylogenetic networks. On the one hand, we consider the treelike content of a phylogenetic network, e.g. the (multi)set of phylogenetic trees displayed by a network and the so-called lowest stable ancestor tree associated with it. On the other hand, we derive the phylogenetic diversity of subsets of taxa and biodiversity indices directly from the internal structure of the network. We consider both approaches that are independent of so-called inheritance probabilities as well as approaches that explicitly incorporate these probabilities. Furthermore, we introduce our software package NetDiversity, which is implemented in Perl and allows for the calculation of all generalized measures of phylogenetic diversity and generalized phylogenetic diversity indices established in this note that are independent of inheritance probabilities. We apply our methods to a phylogenetic network representing the evolutionary relationships among swordtails and platyfishes (Xiphophorus: Poeciliidae), a group of species characterized by widespread hybridization. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Systems genetics identifies a convergent gene network for cognition and neurodevelopmental disease.

    Science.gov (United States)

    Johnson, Michael R; Shkura, Kirill; Langley, Sarah R; Delahaye-Duriez, Andree; Srivastava, Prashant; Hill, W David; Rackham, Owen J L; Davies, Gail; Harris, Sarah E; Moreno-Moral, Aida; Rotival, Maxime; Speed, Doug; Petrovski, Slavé; Katz, Anaïs; Hayward, Caroline; Porteous, David J; Smith, Blair H; Padmanabhan, Sandosh; Hocking, Lynne J; Starr, John M; Liewald, David C; Visconti, Alessia; Falchi, Mario; Bottolo, Leonardo; Rossetti, Tiziana; Danis, Bénédicte; Mazzuferi, Manuela; Foerch, Patrik; Grote, Alexander; Helmstaedter, Christoph; Becker, Albert J; Kaminski, Rafal M; Deary, Ian J; Petretto, Enrico

    2016-02-01

    Genetic determinants of cognition are poorly characterized, and their relationship to genes that confer risk for neurodevelopmental disease is unclear. Here we performed a systems-level analysis of genome-wide gene expression data to infer gene-regulatory networks conserved across species and brain regions. Two of these networks, M1 and M3, showed replicable enrichment for common genetic variants underlying healthy human cognitive abilities, including memory. Using exome sequence data from 6,871 trios, we found that M3 genes were also enriched for mutations ascertained from patients with neurodevelopmental disease generally, and intellectual disability and epileptic encephalopathy in particular. M3 consists of 150 genes whose expression is tightly developmentally regulated, but which are collectively poorly annotated for known functional pathways. These results illustrate how systems-level analyses can reveal previously unappreciated relationships between neurodevelopmental disease-associated genes in the developed human brain, and provide empirical support for a convergent gene-regulatory network influencing cognition and neurodevelopmental disease.

  7. Treating network junctions in finite volume solution of transient gas flow models

    Science.gov (United States)

    Bermúdez, Alfredo; López, Xián; Vázquez-Cendón, M. Elena

    2017-09-01

    A finite volume scheme for the numerical solution of a non-isothermal non-adiabatic compressible flow model for gas transportation networks on non-flat topography is introduced. Unlike standard Euler equations, the model takes into account wall friction, variable height and heat transfer between the pipe and the environment which are source terms. The case of one single pipe was considered in a previous reference by the authors, [8], where a finite volume method with upwind discretization of the flux and source terms has been proposed in order to get a well-balanced scheme. The main goal of the present paper is to go a step further by considering a network of pipes. The main issue is the treatment of junctions for which container-like 2D finite volumes are introduced. The couplings between pipes (1D) and containers (2D) are carefully described and the conservation properties are analyzed. Numerical tests including real gas networks are solved showing the performance of the proposed methodology.

  8. Overview of energy demand and opportunities for conservation

    Energy Technology Data Exchange (ETDEWEB)

    Graham, P. J.

    1977-10-15

    The widespread practice of conservation could make a substantial reduction in the rate of growth of demand and hence in the rate at which resources need to be developed and consumed. An attempt is not made to show that conservation is an alternative to increasing energy supply. After reviewing the consumption of energy before the 1973 energy crisis, the main features of conservation which have brought it to the forefront of energy policy are examined. Some information on present consumption patterns in New Zealand is presented.

  9. Evolutionary analysis of apolipoprotein E by Maximum Likelihood and complex network methods

    Directory of Open Access Journals (Sweden)

    Leandro de Jesus Benevides

    Full Text Available Abstract Apolipoprotein E (apo E is a human glycoprotein with 299 amino acids, and it is a major component of very low density lipoproteins (VLDL and a group of high-density lipoproteins (HDL. Phylogenetic studies are important to clarify how various apo E proteins are related in groups of organisms and whether they evolved from a common ancestor. Here, we aimed at performing a phylogenetic study on apo E carrying organisms. We employed a classical and robust method, such as Maximum Likelihood (ML, and compared the results using a more recent approach based on complex networks. Thirty-two apo E amino acid sequences were downloaded from NCBI. A clear separation could be observed among three major groups: mammals, fish and amphibians. The results obtained from ML method, as well as from the constructed networks showed two different groups: one with mammals only (C1 and another with fish (C2, and a single node with the single sequence available for an amphibian. The accordance in results from the different methods shows that the complex networks approach is effective in phylogenetic studies. Furthermore, our results revealed the conservation of apo E among animal groups.

  10. An Energy-Efficient Sleep Strategy for Target Tracking Sensor Networks

    Directory of Open Access Journals (Sweden)

    Juan FENG

    2014-02-01

    Full Text Available Energy efficiency is very important for sensor networks since sensor nodes have limited energy supply from battery. So far, many researches have been focused on this issue, while less emphasis was placed on the optimal sleep time of each node. This paper proposed an adaptive energy conservation strategy for target tracking based on a grid network structure, where each node autonomously determines when and if to sleep. It allows sensor nodes far away from targets to sleep to save energy and guarantee the tracking accuracy. The proposed approach extend network lifetime by adopting an adaptive sleep scheduling scheme that combines the local power management (PM and the adaptive coordinate PM strategies to schedule the activities of sensor nodes. And each node can choose an optimal sleep time so as to make system adaptive and energy-efficient. We show the performance of our approach in terms of energy drop, comparing it to a naive approach, dynamic PM with fixed sleep time and the coordinate PM strategies. From the experimental results, it is readily seen that the efficiency of the proposed approach.

  11. Modularity of gene-regulatory networks revealed in sea-star development

    Directory of Open Access Journals (Sweden)

    Degnan Bernard M

    2011-01-01

    Full Text Available Abstract Evidence that conserved developmental gene-regulatory networks can change as a unit during deutersostome evolution emerges from a study published in BMC Biology. This shows that genes consistently expressed in anterior brain patterning in hemichordates and chordates are expressed in a similar spatial pattern in another deuterostome, an asteroid echinoderm (sea star, but in a completely different developmental context (the animal-vegetal axis. This observation has implications for hypotheses on the type of development present in the deuterostome common ancestor. See research article: http://www.biomedcentral.com/1741-7007/8/143/abstract

  12. Evolution of SH2 domains and phosphotyrosine signalling networks

    Science.gov (United States)

    Liu, Bernard A.; Nash, Piers D.

    2012-01-01

    Src homology 2 (SH2) domains mediate selective protein–protein interactions with tyrosine phosphorylated proteins, and in doing so define specificity of phosphotyrosine (pTyr) signalling networks. SH2 domains and protein-tyrosine phosphatases expand alongside protein-tyrosine kinases (PTKs) to coordinate cellular and organismal complexity in the evolution of the unikont branch of the eukaryotes. Examination of conserved families of PTKs and SH2 domain proteins provides fiduciary marks that trace the evolutionary landscape for the development of complex cellular systems in the proto-metazoan and metazoan lineages. The evolutionary provenance of conserved SH2 and PTK families reveals the mechanisms by which diversity is achieved through adaptations in tissue-specific gene transcription, altered ligand binding, insertions of linear motifs and the gain or loss of domains following gene duplication. We discuss mechanisms by which pTyr-mediated signalling networks evolve through the development of novel and expanded families of SH2 domain proteins and the elaboration of connections between pTyr-signalling proteins. These changes underlie the variety of general and specific signalling networks that give rise to tissue-specific functions and increasingly complex developmental programmes. Examination of SH2 domains from an evolutionary perspective provides insight into the process by which evolutionary expansion and modification of molecular protein interaction domain proteins permits the development of novel protein-interaction networks and accommodates adaptation of signalling networks. PMID:22889907

  13. How conserved are the conserved 16S-rRNA regions?

    Directory of Open Access Journals (Sweden)

    Marcel Martinez-Porchas

    2017-02-01

    Full Text Available The 16S rRNA gene has been used as master key for studying prokaryotic diversity in almost every environment. Despite the claim of several researchers to have the best universal primers, the reality is that no primer has been demonstrated to be truly universal. This suggests that conserved regions of the gene may not be as conserved as expected. The aim of this study was to evaluate the conservation degree of the so-called conserved regions flanking the hypervariable regions of the 16S rRNA gene. Data contained in SILVA database (release 123 were used for the study. Primers reported as matches of each conserved region were assembled to form contigs; sequences sizing 12 nucleotides (12-mers were extracted from these contigs and searched into the entire set of SILVA sequences. Frequency analysis shown that extreme regions, 1 and 10, registered the lowest frequencies. 12-mer frequencies revealed segments of contigs that were not as conserved as expected (≤90%. Fragments corresponding to the primer contigs 3, 4, 5b and 6a were recovered from all sequences in SILVA database. Nucleotide frequency analysis in each consensus demonstrated that only a small fraction of these so-called conserved regions is truly conserved in non-redundant sequences. It could be concluded that conserved regions of the 16S rRNA gene exhibit considerable variation that has to be considered when using this gene as biomarker.

  14. Increasing participation in incentive programs for biodiversity conservation.

    Science.gov (United States)

    Sorice, Michael G; Oh, Chi-Ok; Gartner, Todd; Snieckus, Mary; Johnson, Rhett; Donlan, C Josh

    2013-07-01

    Engaging private landowners in conservation activities for imperiled species is critical to maintaining and enhancing biodiversity. Market-based approaches can incentivize conservation behaviors on private lands by shifting the benefit-cost ratio of engaging in activities that result in net conservation benefits for target species. In the United States and elsewhere, voluntary conservation agreements with financial incentives are becoming an increasingly common strategy. While the influence of program design and delivery of voluntary conservation programs is often overlooked, these aspects are critical to achieving the necessary participation to attain landscape-scale outcomes. Using a sample of family-forest landowners in the southeast United States, we show how preferences for participation in a conservation program to protect an at-risk species, the gopher tortoise (Gopherus polyphemus), are related to program structure, delivery, and perceived efficacy. Landowners were most sensitive to programs that are highly controlling, require permanent conservation easements, and put landowners at risk for future regulation. Programs designed with greater levels of compensation and that support landowners' autonomy to make land management decisions can increase participation and increase landowner acceptance of program components that are generally unfavorable, like long-term contracts and permanent easements. There is an inherent trade-off between maximizing participation and maximizing the conservation benefits when designing a conservation incentive program. For conservation programs targeting private lands to achieve landscape-level benefits, they must attract a critical level of participation that creates a connected mosaic of conservation benefits. Yet, programs with attributes that strive to maximize conservation benefits within a single agreement (and reduce risks of failure) are likely to have lower participation, and thus lower landscape benefits. Achieving

  15. Conservation

    NARCIS (Netherlands)

    Noteboom, H.P.

    1985-01-01

    The IUCN/WWF Plants Conservation Programme 1984 — 1985. World Wildlife Fund chose plants to be the subject of their fund-raising campaign in the period 1984 — 1985. The objectives were to: 1. Use information techniques to achieve the conservation objectives of the Plants Programme – to save plants;

  16. Elucidating gene function and function evolution through comparison of co-expression networks in plants

    Directory of Open Access Journals (Sweden)

    Marek eMutwil

    2014-08-01

    Full Text Available The analysis of gene expression data has shown that transcriptionally coordinated (co-expressed genes are often functionally related, enabling scientists to use expression data in gene function prediction. This Focused Review discusses our original paper (Large-scale co-expression approach to dissect secondary cell wall formation across plant species, Frontiers in Plant Science 2:23. In this paper we applied cross-species analysis to co-expression networks of genes involved in cellulose biosynthesis. We show that the co-expression networks from different species are highly similar, indicating that whole biological pathways are conserved across species. This finding has two important implications. First, the analysis can transfer gene function annotation from well-studied plants, such as Arabidopsis, to other, uncharacterized plant species. As the analysis finds genes that have similar sequence and similar expression pattern across different organisms, functionally equivalent genes can be identified. Second, since co-expression analyses are often noisy, a comparative analysis should have higher performance, as parts of co-expression networks that are conserved are more likely to be functionally relevant. In this Focused Review, we outline the comparative analysis done in the original paper and comment on the recent advances and approaches that allow comparative analyses of co-function networks. We hypothesize that, in comparison to simple co-expression analysis, comparative analysis would yield more accurate gene function predictions. Finally, by combining comparative analysis with genomic information of green plants, we propose a possible composition of cellulose biosynthesis machinery during earlier stages of plant evolution.

  17. Farmers' Willingness to Adopt Conservation Agriculture: New Evidence from Lebanon.

    Science.gov (United States)

    Chalak, Ali; Irani, Alexandra; Chaaban, Jad; Bashour, Issam; Seyfert, Karin; Smoot, Kaitlyn; Abebe, Gumataw Kifle

    2017-10-01

    With increasing food insecurity and climate change, conservation agriculture has emerged as a sustainable alternative to intensive conventional agriculture as a source of food supply. Yet the adoption rate of conservation agriculture is still low. Our paper analyses the factors affecting farmers' willingness to adopt conservation agriculture in Lebanon. The findings show that household characteristics-years of farming and farm size affect conservation agriculture adoption. However, household characteristics alone were insufficient to explain conservation agriculture adoption. We found that farming experience, information sources, frequency of irrigation, and severity of weed infestation in the past, participation in specific trainings, and farmers' perception about the long-term impact of conservation agriculture, were key determinants of conservation agriculture adoption. Our paper encourages policymakers to invest in conservation agriculture to overcome food insecurity and environmental changes affecting food systems in the Middle East. The paper also informs agribusiness firms to view conservation agriculture as a viable alternative to strengthen their business relationship with farmers in arid and semi-arid regions.

  18. Farmers' Willingness to Adopt Conservation Agriculture: New Evidence from Lebanon

    Science.gov (United States)

    Chalak, Ali; Irani, Alexandra; Chaaban, Jad; Bashour, Issam; Seyfert, Karin; Smoot, Kaitlyn; Abebe, Gumataw Kifle

    2017-10-01

    With increasing food insecurity and climate change, conservation agriculture has emerged as a sustainable alternative to intensive conventional agriculture as a source of food supply. Yet the adoption rate of conservation agriculture is still low. Our paper analyses the factors affecting farmers' willingness to adopt conservation agriculture in Lebanon. The findings show that household characteristics—years of farming and farm size affect conservation agriculture adoption. However, household characteristics alone were insufficient to explain conservation agriculture adoption. We found that farming experience, information sources, frequency of irrigation, and severity of weed infestation in the past, participation in specific trainings, and farmers' perception about the long-term impact of conservation agriculture, were key determinants of conservation agriculture adoption. Our paper encourages policymakers to invest in conservation agriculture to overcome food insecurity and environmental changes affecting food systems in the Middle East. The paper also informs agribusiness firms to view conservation agriculture as a viable alternative to strengthen their business relationship with farmers in arid and semi-arid regions.

  19. Conservation performance of different conservation governance regimes in the Peruvian Amazon.

    Science.gov (United States)

    Schleicher, Judith; Peres, Carlos A; Amano, Tatsuya; Llactayo, William; Leader-Williams, Nigel

    2017-09-12

    State-controlled protected areas (PAs) have dominated conservation strategies globally, yet their performance relative to other governance regimes is rarely assessed comprehensively. Furthermore, performance indicators of forest PAs are typically restricted to deforestation, although the extent of forest degradation is greater. We address these shortfalls through an empirical impact evaluation of state PAs, Indigenous Territories (ITs), and civil society and private Conservation Concessions (CCs) on deforestation and degradation throughout the Peruvian Amazon. We integrated remote-sensing data with environmental and socio-economic datasets, and used propensity-score matching to assess: (i) how deforestation and degradation varied across governance regimes between 2006-2011; (ii) their proximate drivers; and (iii) whether state PAs, CCs and ITs avoided deforestation and degradation compared with logging and mining concessions, and the unprotected landscape. CCs, state PAs, and ITs all avoided deforestation and degradation compared to analogous areas in the unprotected landscape. CCs and ITs were on average more effective in this respect than state PAs, showing that local governance can be equally or more effective than centralized state regimes. However, there were no consistent differences between conservation governance regimes when matched to logging and mining concessions. Future impact assessments would therefore benefit from further disentangling governance regimes across unprotected land.

  20. Application research on big data in energy conservation and emission reduction of transportation industry

    Science.gov (United States)

    Bai, Bingdong; Chen, Jing; Wang, Mei; Yao, Jingjing

    2017-06-01

    In the context of big data age, the energy conservation and emission reduction of transportation is a natural big data industry. The planning, management, decision-making of energy conservation and emission reduction of transportation and other aspects should be supported by the analysis and forecasting of large amounts of data. Now, with the development of information technology, such as intelligent city, sensor road and so on, information collection technology in the direction of the Internet of things gradually become popular. The 3G/4G network transmission technology develop rapidly, and a large number of energy conservation and emission reduction of transportation data is growing into a series with different ways. The government not only should be able to make good use of big data to solve the problem of energy conservation and emission reduction of transportation, but also to explore and use a large amount of data behind the hidden value. Based on the analysis of the basic characteristics and application technology of energy conservation and emission reduction of transportation data, this paper carries out its application research in energy conservation and emission reduction of transportation industry, so as to provide theoretical basis and reference value for low carbon management.

  1. Accounting for results: how conservation organizations report performance information.

    Science.gov (United States)

    Rissman, Adena R; Smail, Robert

    2015-04-01

    Environmental program performance information is in high demand, but little research suggests why conservation organizations differ in reporting performance information. We compared performance measurement and reporting by four private-land conservation organizations: Partners for Fish and Wildlife in the US Fish and Wildlife Service (national government), Forest Stewardship Council-US (national nonprofit organization), Land and Water Conservation Departments (local government), and land trusts (local nonprofit organization). We asked: (1) How did the pattern of performance reporting relationships vary across organizations? (2) Was political conflict among organizations' principals associated with greater performance information? and (3) Did performance information provide evidence of program effectiveness? Based on our typology of performance information, we found that most organizations reported output measures such as land area or number of contracts, some reported outcome indicators such as adherence to performance standards, but few modeled or measured environmental effects. Local government Land and Water Conservation Departments reported the most types of performance information, while local land trusts reported the fewest. The case studies suggest that governance networks influence the pattern and type of performance reporting, that goal conflict among principles is associated with greater performance information, and that performance information provides unreliable causal evidence of program effectiveness. Challenging simple prescriptions to generate more data as evidence, this analysis suggests (1) complex institutional and political contexts for environmental program performance and (2) the need to supplement performance measures with in-depth evaluations that can provide causal inferences about program effectiveness.

  2. Designing Local-Scale Marine Protected Area Networks in the Central Saudi Arabian Red Sea

    KAUST Repository

    Khalil, Maha T.

    2015-12-01

    Coral reefs around the world are at risk from overexploitation and climate change, and coral reefs of the Red Sea are no exception. Science-based designation of marine protected areas (MPAs), within which human activities are restricted, has become a popular method for conserving biodiversity, restoring degraded habitats, and replenishing depleted populations. The aim of this project was to explore adaptable methods for designing locally-manageable MPAs for various conservation goals near Thuwal in the central Saudi Arabian Red Sea while allowing human activities to continue. First, the potential for using simple spatial habitat distribution metrics to aid in designing MPAs that are well-connected with larval supply was explored. Results showed that the degree of habitat patchiness may be positively correlated with realized dispersal distances, making it possible to space MPAs further apart in patchier habitats while still maintaining larval connectivity. However, this relationship requires further study and may be informative to MPA design only in the absence of spatially-explicit empirical dispersal data. Next, biological data was collected, and the spatial variation in biomass, trophic structure, biodiversity, and community assemblages on Thuwal reefs was analyzed in order to inform the process of prioritizing reefs for inclusion in MPA networks. Inshore and offshore reef community assemblages were found to be different and indicated relatively degraded inshore habitats. These trends were used to select species and benthic categories that would be important to conserve in a local MPA. The abundances of these “conservation features” were then modeled throughout the study area, and the decision support software “Marxan” was used to design MPA networks in Thuwal that included these features to achieve quantitative objectives. While achieving objectives relevant to fisheries concerns was relatively more challenging, results showed that it is possible to

  3. Conservation.

    Science.gov (United States)

    National Audubon Society, New York, NY.

    This set of teaching aids consists of seven Audubon Nature Bulletins, providing the teacher and student with informational reading on various topics in conservation. The bulletins have these titles: Plants as Makers of Soil, Water Pollution Control, The Ground Water Table, Conservation--To Keep This Earth Habitable, Our Threatened Air Supply,…

  4. Conservation Triage Falls Short Because Conservation Is Not Like Emergency Medicine

    Directory of Open Access Journals (Sweden)

    John A. Vucetich

    2017-05-01

    Full Text Available Conservation triage, as a concept, seems to have been born from analogizing circumstances that characterize conservation with triage, as the concept applies to emergency medicine. Careful consideration—facilitated through the aid of formal argumentation—demonstrates the critical limitations of the analogy. Those limitations reveal how the concept of conservation triage falls short. For example, medical triage presupposes that resources available for an emergency are limited and fixed. By contrast, the resources available for conservation are not fixed. Moreover, the ethics of prioritization in medical triage is characterized by there being universal agreement on the moral value of the patients. However, in conservation there is not universal agreement on the value of various objects of conservation concern. The looming importance of those features of conservation—disputed values and unfixed resources—make conservation triage a largely un-useful concept.

  5. The Conservative Challenge to Liberalism

    NARCIS (Netherlands)

    Claassen, R.J.G.

    2011-01-01

    This paper reconstructs the political–theoretical triangle between liberalism, communitarianism and conservatism. It shows how these three positions are related to each other and to what extent they are actually incompatible. The substantive outcome is the following thesis: the conservative position

  6. No Reef Is an Island: Integrating Coral Reef Connectivity Data into the Design of Regional-Scale Marine Protected Area Networks.

    Science.gov (United States)

    Schill, Steven R; Raber, George T; Roberts, Jason J; Treml, Eric A; Brenner, Jorge; Halpin, Patrick N

    2015-01-01

    We integrated coral reef connectivity data for the Caribbean and Gulf of Mexico into a conservation decision-making framework for designing a regional scale marine protected area (MPA) network that provides insight into ecological and political contexts. We used an ocean circulation model and regional coral reef data to simulate eight spawning events from 2008-2011, applying a maximum 30-day pelagic larval duration and 20% mortality rate. Coral larval dispersal patterns were analyzed between coral reefs across jurisdictional marine zones to identify spatial relationships between larval sources and destinations within countries and territories across the region. We applied our results in Marxan, a conservation planning software tool, to identify a regional coral reef MPA network design that meets conservation goals, minimizes underlying threats, and maintains coral reef connectivity. Our results suggest that approximately 77% of coral reefs identified as having a high regional connectivity value are not included in the existing MPA network. This research is unique because we quantify and report coral larval connectivity data by marine ecoregions and Exclusive Economic Zones (EZZ) and use this information to identify gaps in the current Caribbean-wide MPA network by integrating asymmetric connectivity information in Marxan to design a regional MPA network that includes important reef network connections. The identification of important reef connectivity metrics guides the selection of priority conservation areas and supports resilience at the whole system level into the future.

  7. No Reef Is an Island: Integrating Coral Reef Connectivity Data into the Design of Regional-Scale Marine Protected Area Networks.

    Directory of Open Access Journals (Sweden)

    Steven R Schill

    Full Text Available We integrated coral reef connectivity data for the Caribbean and Gulf of Mexico into a conservation decision-making framework for designing a regional scale marine protected area (MPA network that provides insight into ecological and political contexts. We used an ocean circulation model and regional coral reef data to simulate eight spawning events from 2008-2011, applying a maximum 30-day pelagic larval duration and 20% mortality rate. Coral larval dispersal patterns were analyzed between coral reefs across jurisdictional marine zones to identify spatial relationships between larval sources and destinations within countries and territories across the region. We applied our results in Marxan, a conservation planning software tool, to identify a regional coral reef MPA network design that meets conservation goals, minimizes underlying threats, and maintains coral reef connectivity. Our results suggest that approximately 77% of coral reefs identified as having a high regional connectivity value are not included in the existing MPA network. This research is unique because we quantify and report coral larval connectivity data by marine ecoregions and Exclusive Economic Zones (EZZ and use this information to identify gaps in the current Caribbean-wide MPA network by integrating asymmetric connectivity information in Marxan to design a regional MPA network that includes important reef network connections. The identification of important reef connectivity metrics guides the selection of priority conservation areas and supports resilience at the whole system level into the future.

  8. Ecosystem services-based SWOT analysis of protected areas for conservation strategies.

    Science.gov (United States)

    Scolozzi, Rocco; Schirpke, Uta; Morri, Elisa; D'Amato, Dalia; Santolini, Riccardo

    2014-12-15

    An ecosystem services-based SWOT analysis is proposed in order to identify and quantify internal and external factors supporting or threatening the conservation effectiveness of protected areas. The proposed approach concerns both the ecological and the social perspective. Strengths and weaknesses, opportunities and threats were evaluated based on 12 selected environmental and socio-economic indicators for all terrestrial Italian protected areas, belonging to the Natura 2000 network, and for their 5-km buffer area. The indicators, used as criteria within a multi-criteria assessment, include: core area, cost-distance between protected areas, changes in ecosystem services values, intensification of land use, and urbanization. The results were aggregated for three biogeographical regions, Alpine, Continental, and Mediterranean, indicating that Alpine sites have more opportunities and strengths than Continental and Mediterranean sites. The results call attention to where connectivity and land-use changes may have stronger influence on protected areas, in particular, whereas urbanization or intensification of agriculture may hamper conservation goals of protected areas. The proposed SWOT analysis provides helpful information for a multiple scale perspective and for identifying conservation priorities and for defining management strategies to assure biodiversity conservation and ecosystem services provision. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Limitations of outsourcing on-the-ground biodiversity conservation.

    Science.gov (United States)

    Iacona, Gwenllian D; Bode, Michael; Armsworth, Paul R

    2016-12-01

    To counteract global species decline, modern biodiversity conservation engages in large projects, spends billions of dollars, and includes many organizations working simultaneously within regions. To add to this complexity, the conservation sector has hierarchical structure, where conservation actions are often outsourced by funders (foundations, government, etc.) to local organizations that work on-the-ground. In contrast, conservation science usually assumes that a single organization makes resource allocation decisions. This discrepancy calls for theory to understand how the expected biodiversity outcomes change when interactions between organizations are accounted for. Here, we used a game theoretic model to explore how biodiversity outcomes are affected by vertical and horizontal interactions between 3 conservation organizations: a funder that outsourced its actions and 2 local conservation organizations that work on-the-ground. Interactions between the organizations changed the spending decisions made by individual organizations, and thereby the magnitude and direction of the conservation benefits. We showed that funders would struggle to incentivize recipient organizations with set priorities to perform desired actions, even when they control substantial amounts of the funding and employ common contracting approaches to enhance outcomes. Instead, biodiversity outcomes depended on priority alignment across the organizations. Conservation outcomes for the funder were improved by strategic interactions when organizational priorities were well aligned, but decreased when priorities were misaligned. Meanwhile, local organizations had improved outcomes regardless of alignment due to additional funding in the system. Given that conservation often involves the aggregate actions of multiple organizations with different objectives, strategic interactions between organizations need to be considered if we are to predict possible outcomes of conservation programs or

  10. Adaptive comanagement of a marine protected area network in Fiji.

    Science.gov (United States)

    Weeks, Rebecca; Jupiter, Stacy D

    2013-12-01

    Adaptive management of natural resources is an iterative process of decision making whereby management strategies are progressively changed or adjusted in response to new information. Despite an increasing focus on the need for adaptive conservation strategies, there remain few applied examples. We describe the 9-year process of adaptive comanagement of a marine protected area network in Kubulau District, Fiji. In 2011, a review of protected area boundaries and management rules was motivated by the need to enhance management effectiveness and the desire to improve resilience to climate change. Through a series of consultations, with the Wildlife Conservation Society providing scientific input to community decision making, the network of marine protected areas was reconfigured so as to maximize resilience and compliance. Factors identified as contributing to this outcome include well-defined resource-access rights; community respect for a flexible system of customary governance; long-term commitment and presence of comanagement partners; supportive policy environment for comanagement; synthesis of traditional management approaches with systematic monitoring; and district-wide coordination, which provided a broader spatial context for adaptive-management decision making. Co-Manejo Adaptativo de una Red de Áreas Marinas Protegidas en Fiyi. © 2013 The Authors. Conservation Biology published by Wiley Periodicals, Inc., on behalf of the Society for Conservation Biology.

  11. Restricted-range fishes and the conservation of Brazilian freshwaters.

    Science.gov (United States)

    Nogueira, Cristiano; Buckup, Paulo A; Menezes, Naercio A; Oyakawa, Osvaldo T; Kasecker, Thais P; Ramos Neto, Mario B; da Silva, José Maria C

    2010-06-30

    Freshwaters are the most threatened ecosystems on earth. Although recent assessments provide data on global priority regions for freshwater conservation, local scale priorities remain unknown. Refining the scale of global biodiversity assessments (both at terrestrial and freshwater realms) and translating these into conservation priorities on the ground remains a major challenge to biodiversity science, and depends directly on species occurrence data of high taxonomic and geographic resolution. Brazil harbors the richest freshwater ichthyofauna in the world, but knowledge on endemic areas and conservation in Brazilian rivers is still scarce. Using data on environmental threats and revised species distribution data we detect and delineate 540 small watershed areas harboring 819 restricted-range fishes in Brazil. Many of these areas are already highly threatened, as 159 (29%) watersheds have lost more than 70% of their original vegetation cover, and only 141 (26%) show significant overlap with formally protected areas or indigenous lands. We detected 220 (40%) critical watersheds overlapping hydroelectric dams or showing both poor formal protection and widespread habitat loss; these sites harbor 344 endemic fish species that may face extinction if no conservation action is in place in the near future. We provide the first analysis of site-scale conservation priorities in the richest freshwater ecosystems of the globe. Our results corroborate the hypothesis that freshwater biodiversity has been neglected in former conservation assessments. The study provides a simple and straightforward method for detecting freshwater priority areas based on endemism and threat, and represents a starting point for integrating freshwater and terrestrial conservation in representative and biogeographically consistent site-scale conservation strategies, that may be scaled-up following naturally linked drainage systems. Proper management (e. g. forestry code enforcement, landscape

  12. Frogs, fish and forestry: An integrated watershed network paradigm conserves biodiversity and ecological services

    Science.gov (United States)

    Hartwell H. Welsh Jr.

    2011-01-01

    Successfully addressing the multitude of stresses influencing forest catchments, their native biota, and the vital ecological services they provide humanity will require adapting an integrated view that incorporates the full range of natural and anthropogenic disturbances acting on these landscapes and their embedded fluvial networks. The concepts of dendritic networks...

  13. Finding Solvable Units of Variables in Nonlinear ODEs of ECM Degradation Pathway Network

    Directory of Open Access Journals (Sweden)

    Shuji Kawasaki

    2017-01-01

    Full Text Available We consider ordinary differential equation (ODE model for a pathway network that arises in extracellular matrix (ECM degradation. For solving the ODEs, we propose applying the mass conservation law (MCL, together with a stoichiometry called doubling rule, to them. Then it leads to extracting new units of variables in the ODEs that can be solved explicitly, at least in principle. The simulation results for the ODE solutions show that the numerical solutions are indeed in good accord with theoretical solutions and satisfy the MALs.

  14. Finding Solvable Units of Variables in Nonlinear ODEs of ECM Degradation Pathway Network.

    Science.gov (United States)

    Kawasaki, Shuji; Minerva, Dhisa; Itano, Keiko; Suzuki, Takashi

    2017-01-01

    We consider ordinary differential equation (ODE) model for a pathway network that arises in extracellular matrix (ECM) degradation. For solving the ODEs, we propose applying the mass conservation law (MCL), together with a stoichiometry called doubling rule , to them. Then it leads to extracting new units of variables in the ODEs that can be solved explicitly, at least in principle. The simulation results for the ODE solutions show that the numerical solutions are indeed in good accord with theoretical solutions and satisfy the MALs.

  15. Setting conservation priorities.

    Science.gov (United States)

    Wilson, Kerrie A; Carwardine, Josie; Possingham, Hugh P

    2009-04-01

    A generic framework for setting conservation priorities based on the principles of classic decision theory is provided. This framework encapsulates the key elements of any problem, including the objective, the constraints, and knowledge of the system. Within the context of this framework the broad array of approaches for setting conservation priorities are reviewed. While some approaches prioritize assets or locations for conservation investment, it is concluded here that prioritization is incomplete without consideration of the conservation actions required to conserve the assets at particular locations. The challenges associated with prioritizing investments through time in the face of threats (and also spatially and temporally heterogeneous costs) can be aided by proper problem definition. Using the authors' general framework for setting conservation priorities, multiple criteria can be rationally integrated and where, how, and when to invest conservation resources can be scheduled. Trade-offs are unavoidable in priority setting when there are multiple considerations, and budgets are almost always finite. The authors discuss how trade-offs, risks, uncertainty, feedbacks, and learning can be explicitly evaluated within their generic framework for setting conservation priorities. Finally, they suggest ways that current priority-setting approaches may be improved.

  16. Cosmological constant is a conserved charge

    Science.gov (United States)

    Chernyavsky, Dmitry; Hajian, Kamal

    2018-06-01

    Cosmological constant can always be considered as the on-shell value of a top form in gravitational theories. The top form is the field strength of a gauge field, and the theory enjoys a gauge symmetry. We show that cosmological constant is the charge of the global part of the gauge symmetry, and is conserved irrespective of the dynamics of the metric and other fields. In addition, we introduce its conjugate chemical potential, and prove the generalized first law of thermodynamics which includes variation of cosmological constant as a conserved charge. We discuss how our new term in the first law is related to the volume–pressure term. In parallel with the seminal Wald entropy, this analysis suggests that pressure can also be considered as a conserved charge.

  17. The US Fire Learning Network: Springing a Rigidity Trap through Multiscalar Collaborative Networks

    Directory of Open Access Journals (Sweden)

    William Hale. Butler

    2010-09-01

    Full Text Available Wildland fire management in the United States is caught in a rigidity trap, an inability to apply novelty and innovation in the midst of crisis. Despite wide recognition that public agencies should engage in ecological fire restoration, fire suppression still dominates planning and management, and restoration has failed to gain traction. The U.S. Fire Learning Network (FLN, a multiscalar collaborative endeavor established in 2002 by federal land management agencies and The Nature Conservancy, offers the potential to overcome barriers that inhibit restoration planning and management. By circulating people, planning products, and information among landscape- and regional-scale collaboratives, this network has facilitated the development and dissemination of innovative approaches to ecological fire restoration. Through experimentation and innovation generated in the network, the FLN has fostered change by influencing fire and land management plans as well as federal policy. We suggest that multiscalar collaborative planning networks such as the FLN can facilitate overcoming the rigidity traps that prevent resource management agencies from responding to complex cross-scalar problems.

  18. Measuring the difference made by conservation initiatives: protected areas and their environmental and social impacts.

    Science.gov (United States)

    Ferraro, Paul J; Pressey, Robert L

    2015-11-05

    Success in conservation depends on our ability to reduce human pressures in areas that harbour biological diversity and ecosystem services. Legally protecting some of these areas through the creation of protected areas is a key component of conservation efforts globally. To develop effective protected area networks, practitioners need credible, scientific evidence about the degree to which protected areas affect environmental and social outcomes, and how these effects vary with context. Such evidence has been lacking, but the situation is changing as conservation scientists adopt more sophisticated research designs for evaluating protected areas' past impacts and for predicting their future impacts. Complementing these scientific advances, conservation funders and practitioners are paying increasing attention to evaluating their investments with more scientifically rigorous evaluation designs. This theme issue highlights recent advances in the science of protected area evaluations and explores the challenges to developing a more credible evidence base that can help societies achieve their goals of protecting nature while enhancing human welfare. © 2015 The Author(s).

  19. Abstracts of the TICCIH Canada conference on industrial strength : conserving Canada's industrial heritage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    The conservation and rehabilitation of Canada's industrial sites represents some of the most innovative examples of heritage site development. This conference provided a forum for various stakeholder, conservation specialists, and community planners to discuss issues and strategies for preserving Canada's industrial heritage. Challenges related to preserving industrial heritage as historic sites and museums were discussed. Methods of strengthening community identity and engagement with industrial heritage preservation were also presented. The future of an industrial heritage network was considered. The conference was divided into the following 7 sessions: (1) new site development, brownfield to heritage sites, (2) inventories, evaluation and awareness, (3) industrial heritage of Hamilton, (4) conservation, adaptive reuse and economic viability, a case study of the Toronto distillery project, (5) industrial landscapes, (6) preserving the intangibles, and (7) industrial heritage museums, issues in conservation, interpretation, and sustainability. The conference featured 19 papers, of which 2 have been catalogued separately for inclusion in this database. refs., tabs., figs.

  20. Emerging Network-Based Tools in Movement Ecology.

    Science.gov (United States)

    Jacoby, David M P; Freeman, Robin

    2016-04-01

    New technologies have vastly increased the available data on animal movement and behaviour. Consequently, new methods deciphering the spatial and temporal interactions between individuals and their environments are vital. Network analyses offer a powerful suite of tools to disentangle the complexity within these dynamic systems, and we review these tools, their application, and how they have generated new ecological and behavioural insights. We suggest that network theory can be used to model and predict the influence of ecological and environmental parameters on animal movement, focusing on spatial and social connectivity, with fundamental implications for conservation. Refining how we construct and randomise spatial networks at different temporal scales will help to establish network theory as a prominent, hypothesis-generating tool in movement ecology. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Self organization of wireless sensor networks using ultra-wideband radios

    Science.gov (United States)

    Dowla, Farid U [Castro Valley, CA; Nekoogar, Franak [San Ramon, CA; Spiridon, Alex [Palo Alto, CA

    2009-06-16

    A novel UWB communications method and system that provides self-organization for wireless sensor networks is introduced. The self-organization is in terms of scalability, power conservation, channel estimation, and node synchronization in wireless sensor networks. The UWB receiver in the present invention adds two new tasks to conventional TR receivers. The two additional units are SNR enhancing unit and timing acquisition and tracking unit.

  2. The Conservation Ideological State Apparatus

    Directory of Open Access Journals (Sweden)

    Jared D Margulies

    2018-01-01

    Full Text Available This article considers Louis Althusser's theory of the ideological state apparatuses (ISAs for advancing political ecology scholarship on the functioning of the state in violent environments. I reflect on a series of events in which a state forest department in South India attempted to recast violent conflicts between themselves and local communities over access to natural resources and a protected area as a debate over human-wildlife conflicts. Through the example of conservation as ideology in Wayanad, Kerala, I show how the ISAs articulate the functioning of ideology within the state apparatuses in order for us to understand the larger mechanics of the state apparatus and the reproduction of the relations of production necessary for the reproduction of capitalism. Revisiting the ISAs as a theoretical framework for studies in political ecology and conservation is timely given the resurgence of militarised conservation tactics, the emancipatory aims of Althusser's theory, and political ecology's turn towards praxis.

  3. Group decisions in biodiversity conservation: implications from game theory.

    Science.gov (United States)

    Frank, David M; Sarkar, Sahotra

    2010-05-27

    Decision analysis and game theory have proved useful tools in various biodiversity conservation planning and modeling contexts. This paper shows how game theory may be used to inform group decisions in biodiversity conservation scenarios by modeling conflicts between stakeholders to identify Pareto-inefficient Nash equilibria. These are cases in which each agent pursuing individual self-interest leads to a worse outcome for all, relative to other feasible outcomes. Three case studies from biodiversity conservation contexts showing this feature are modeled to demonstrate how game-theoretical representation can inform group decision-making. The mathematical theory of games is used to model three biodiversity conservation scenarios with Pareto-inefficient Nash equilibria: (i) a two-agent case involving wild dogs in South Africa; (ii) a three-agent raptor and grouse conservation scenario from the United Kingdom; and (iii) an n-agent fish and coral conservation scenario from the Philippines. In each case there is reason to believe that traditional mechanism-design solutions that appeal to material incentives may be inadequate, and the game-theoretical analysis recommends a resumption of further deliberation between agents and the initiation of trust--and confidence--building measures. Game theory can and should be used as a normative tool in biodiversity conservation contexts: identifying scenarios with Pareto-inefficient Nash equilibria enables constructive action in order to achieve (closer to) optimal conservation outcomes, whether by policy solutions based on mechanism design or otherwise. However, there is mounting evidence that formal mechanism-design solutions may backfire in certain cases. Such scenarios demand a return to group deliberation and the creation of reciprocal relationships of trust.

  4. Group decisions in biodiversity conservation: implications from game theory.

    Directory of Open Access Journals (Sweden)

    David M Frank

    Full Text Available BACKGROUND: Decision analysis and game theory have proved useful tools in various biodiversity conservation planning and modeling contexts. This paper shows how game theory may be used to inform group decisions in biodiversity conservation scenarios by modeling conflicts between stakeholders to identify Pareto-inefficient Nash equilibria. These are cases in which each agent pursuing individual self-interest leads to a worse outcome for all, relative to other feasible outcomes. Three case studies from biodiversity conservation contexts showing this feature are modeled to demonstrate how game-theoretical representation can inform group decision-making. METHODOLOGY AND PRINCIPAL FINDINGS: The mathematical theory of games is used to model three biodiversity conservation scenarios with Pareto-inefficient Nash equilibria: (i a two-agent case involving wild dogs in South Africa; (ii a three-agent raptor and grouse conservation scenario from the United Kingdom; and (iii an n-agent fish and coral conservation scenario from the Philippines. In each case there is reason to believe that traditional mechanism-design solutions that appeal to material incentives may be inadequate, and the game-theoretical analysis recommends a resumption of further deliberation between agents and the initiation of trust--and confidence--building measures. CONCLUSIONS AND SIGNIFICANCE: Game theory can and should be used as a normative tool in biodiversity conservation contexts: identifying scenarios with Pareto-inefficient Nash equilibria enables constructive action in order to achieve (closer to optimal conservation outcomes, whether by policy solutions based on mechanism design or otherwise. However, there is mounting evidence that formal mechanism-design solutions may backfire in certain cases. Such scenarios demand a return to group deliberation and the creation of reciprocal relationships of trust.

  5. Simulation of two-phase flow in horizontal fracture networks with numerical manifold method

    Science.gov (United States)

    Ma, G. W.; Wang, H. D.; Fan, L. F.; Wang, B.

    2017-10-01

    The paper presents simulation of two-phase flow in discrete fracture networks with numerical manifold method (NMM). Each phase of fluids is considered to be confined within the assumed discrete interfaces in the present method. The homogeneous model is modified to approach the mixed fluids. A new mathematical cover formation for fracture intersection is proposed to satisfy the mass conservation. NMM simulations of two-phase flow in a single fracture, intersection, and fracture network are illustrated graphically and validated by the analytical method or the finite element method. Results show that the motion status of discrete interface significantly depends on the ratio of mobility of two fluids rather than the value of the mobility. The variation of fluid velocity in each fracture segment and the driven fluid content are also influenced by the ratio of mobility. The advantages of NMM in the simulation of two-phase flow in a fracture network are demonstrated in the present study, which can be further developed for practical engineering applications.

  6. Connectivity, cycles, and persistence thresholds in metapopulation networks.

    Directory of Open Access Journals (Sweden)

    Yael Artzy-Randrup

    2010-08-01

    Full Text Available Synthesising the relationships between complexity, connectivity, and the stability of large biological systems has been a longstanding fundamental quest in theoretical biology and ecology. With the many exciting developments in modern network theory, interest in these issues has recently come to the forefront in a range of multidisciplinary areas. Here we outline a new theoretical analysis specifically relevant for the study of ecological metapopulations focusing primarily on marine systems, where subpopulations are generally connected via larval dispersal. Our work determines the qualitative and quantitative conditions by which dispersal and network structure control the persistence of a set of age-structured patch populations. Mathematical modelling combined with a graph theoretic analysis demonstrates that persistence depends crucially on the topology of cycles in the dispersal network which tend to enhance the effect of larvae "returning home." Our method clarifies the impact directly due to network structure, but this almost by definition can only be achieved by examining the simplified case in which patches are identical; an assumption that we later relax. The methodology identifies critical migration routes, whose presence are vital to overall stability, and therefore should have high conservation priority. In contrast, "lonely links," or links in the network that do not participate in a cyclical component, have no impact on persistence and thus have low conservation priority. A number of other intriguing criteria for persistence are derived. Our modelling framework reveals new insights regarding the determinants of persistence, stability, and thresholds in complex metapopulations. In particular, while theoretical arguments have, in the past, suggested that increasing connectivity is a destabilizing feature in complex systems, this is not evident in metapopulation networks where connectivity, cycles, coherency, and heterogeneity all tend

  7. Conserving tigers in working landscapes.

    Science.gov (United States)

    Chanchani, Pranav; Noon, Barry R; Bailey, Larissa L; Warrier, Rekha A

    2016-06-01

    Tiger (Panthera tigris) conservation efforts in Asia are focused on protected areas embedded in human-dominated landscapes. A system of protected areas is an effective conservation strategy for many endangered species if the network is large enough to support stable metapopulations. The long-term conservation of tigers requires that the species be able to meet some of its life-history needs beyond the boundaries of small protected areas and within the working landscape, including multiple-use forests with logging and high human use. However, understanding of factors that promote or limit the occurrence of tigers in working landscapes is incomplete. We assessed the relative influence of protection status, prey occurrence, extent of grasslands, intensity of human use, and patch connectivity on tiger occurrence in the 5400 km(2) Central Terai Landscape of India, adjacent to Nepal. Two observer teams independently surveyed 1009 km of forest trails and water courses distributed across 60 166-km(2) cells. In each cell, the teams recorded detection of tiger signs along evenly spaced trail segments. We used occupancy models that permitted multiscale analysis of spatially correlated data to estimate cell-scale occupancy and segment-scale habitat use by tigers as a function of management and environmental covariates. Prey availability and habitat quality, rather than protected-area designation, influenced tiger occupancy. Tiger occupancy was low in some protected areas in India that were connected to extensive areas of tiger habitat in Nepal, which brings into question the efficacy of current protection and management strategies in both India and Nepal. At a finer spatial scale, tiger habitat use was high in trail segments associated with abundant prey and large grasslands, but it declined as human and livestock use increased. We speculate that riparian grasslands may provide tigers with critical refugia from human activity in the daytime and thereby promote tiger occurrence

  8. Conservation Value

    OpenAIRE

    Tisdell, Clement A.

    2010-01-01

    This paper outlines the significance of the concept of conservation value and discusses ways in which it is determined paying attention to views stemming from utilitarian ethics and from deontological ethics. The importance of user costs in relation to economic decisions about the conservation and use of natural resources is emphasised. Particular attention is given to competing views about the importance of conserving natural resources in order to achieve economic sustainability. This then l...

  9. Further results on universal properties in conservative dynamical systems

    Energy Technology Data Exchange (ETDEWEB)

    Benettin, G [Padua Univ. (Italy). Ist. di Fisica; Galgani, L; Giorgilli, A [Milan Univ. (Italy). Ist. di Fisica; Milan Univ. (Italy). Ist. di Matematica)

    1980-10-11

    In conservative dynamical systems depending on a parameter, sequences of period-doubling bifurcations can be observed by varying the parameter, starting from a stable fixed point. These sequences are analogous to those already known for dissipative systems. The paper shows some new results obtained for two-dimensional conservative mappings.

  10. Conservatives report, but liberals display, greater happiness.

    Science.gov (United States)

    Wojcik, Sean P; Hovasapian, Arpine; Graham, Jesse; Motyl, Matt; Ditto, Peter H

    2015-03-13

    Research suggesting that political conservatives are happier than political liberals has relied exclusively on self-report measures of subjective well-being. We show that this finding is fully mediated by conservatives' self-enhancing style of self-report (study 1; N = 1433) and then describe three studies drawing from "big data" sources to assess liberal-conservative differences in happiness-related behavior (studies 2 to 4; N = 4936). Relative to conservatives, liberals more frequently used positive emotional language in their speech and smiled more intensely and genuinely in photographs. Our results were consistent across large samples of online survey takers, U.S. politicians, Twitter users, and LinkedIn users. Our findings illustrate the nuanced relationship between political ideology, self-enhancement, and happiness and illuminate the contradictory ways that happiness differences can manifest across behavior and self-reports. Copyright © 2015, American Association for the Advancement of Science.

  11. Energy- Efficient Routing Protocols For Wireless Sensor Network A Review

    Directory of Open Access Journals (Sweden)

    Pardeep Kaur

    2017-12-01

    Full Text Available There has been plenty of interest in building and deploying sensor networks. Wireless sensor network is a collection of a large number of small nodes which acts as routers also. These nodes carry very limited power source which is non-rechargeable and non-replaceable which makes energy consumption an significant issue. Energy conservation is a very important issue for prolonging the lifetime of the network. As the sensor nodes act like routers as well the determination of routing technique plays a key role in controlling the consumption of energy. This paper describes the framework of wireless sensor network and the analysis and study of various research work related to Energy Efficient Routing in Wireless Sensor Networks.

  12. MIR@NT@N: a framework integrating transcription factors, microRNAs and their targets to identify sub-network motifs in a meta-regulation network model

    Directory of Open Access Journals (Sweden)

    Wasserman Wyeth W

    2011-03-01

    Full Text Available Abstract Background To understand biological processes and diseases, it is crucial to unravel the concerted interplay of transcription factors (TFs, microRNAs (miRNAs and their targets within regulatory networks and fundamental sub-networks. An integrative computational resource generating a comprehensive view of these regulatory molecular interactions at a genome-wide scale would be of great interest to biologists, but is not available to date. Results To identify and analyze molecular interaction networks, we developed MIR@NT@N, an integrative approach based on a meta-regulation network model and a large-scale database. MIR@NT@N uses a graph-based approach to predict novel molecular actors across multiple regulatory processes (i.e. TFs acting on protein-coding or miRNA genes, or miRNAs acting on messenger RNAs. Exploiting these predictions, the user can generate networks and further analyze them to identify sub-networks, including motifs such as feedback and feedforward loops (FBL and FFL. In addition, networks can be built from lists of molecular actors with an a priori role in a given biological process to predict novel and unanticipated interactions. Analyses can be contextualized and filtered by integrating additional information such as microarray expression data. All results, including generated graphs, can be visualized, saved and exported into various formats. MIR@NT@N performances have been evaluated using published data and then applied to the regulatory program underlying epithelium to mesenchyme transition (EMT, an evolutionary-conserved process which is implicated in embryonic development and disease. Conclusions MIR@NT@N is an effective computational approach to identify novel molecular regulations and to predict gene regulatory networks and sub-networks including conserved motifs within a given biological context. Taking advantage of the M@IA environment, MIR@NT@N is a user-friendly web resource freely available at http

  13. Method and Apparatus for Predicting Unsteady Pressure and Flow Rate Distribution in a Fluid Network

    Science.gov (United States)

    Majumdar, Alok K. (Inventor)

    2009-01-01

    A method and apparatus for analyzing steady state and transient flow in a complex fluid network, modeling phase changes, compressibility, mixture thermodynamics, external body forces such as gravity and centrifugal force and conjugate heat transfer. In some embodiments, a graphical user interface provides for the interactive development of a fluid network simulation having nodes and branches. In some embodiments, mass, energy, and specific conservation equations are solved at the nodes, and momentum conservation equations are solved in the branches. In some embodiments, contained herein are data objects for computing thermodynamic and thermophysical properties for fluids. In some embodiments, the systems of equations describing the fluid network are solved by a hybrid numerical method that is a combination of the Newton-Raphson and successive substitution methods.

  14. An unconditionally stable fully conservative semi-Lagrangian method

    KAUST Repository

    Lentine, Michael

    2011-04-01

    Semi-Lagrangian methods have been around for some time, dating back at least to [3]. Researchers have worked to increase their accuracy, and these schemes have gained newfound interest with the recent widespread use of adaptive grids where the CFL-based time step restriction of the smallest cell can be overwhelming. Since these schemes are based on characteristic tracing and interpolation, they do not readily lend themselves to a fully conservative implementation. However, we propose a novel technique that applies a conservative limiter to the typical semi-Lagrangian interpolation step in order to guarantee that the amount of the conservative quantity does not increase during this advection. In addition, we propose a new second step that forward advects any of the conserved quantity that was not accounted for in the typical semi-Lagrangian advection. We show that this new scheme can be used to conserve both mass and momentum for incompressible flows. For incompressible flows, we further explore properly conserving kinetic energy during the advection step, but note that the divergence free projection results in a velocity field which is inconsistent with conservation of kinetic energy (even for inviscid flows where it should be conserved). For compressible flows, we rely on a recently proposed splitting technique that eliminates the acoustic CFL time step restriction via an incompressible-style pressure solve. Then our new method can be applied to conservatively advect mass, momentum and total energy in order to exactly conserve these quantities, and remove the remaining time step restriction based on fluid velocity that the original scheme still had. © 2011 Elsevier Inc.

  15. New gene evolution in the bonus-TIF1-γ/TRIM33 family impacted the architecture of the vertebrate dorsal-ventral patterning network.

    Science.gov (United States)

    Wisotzkey, Robert G; Quijano, Janine C; Stinchfield, Michael J; Newfeld, Stuart J

    2014-09-01

    Uncovering how a new gene acquires its function and understanding how the function of a new gene influences existing genetic networks are important topics in evolutionary biology. Here, we demonstrate nonconservation for the embryonic functions of Drosophila Bonus and its newest vertebrate relative TIF1-γ/TRIM33. We showed previously that TIF1-γ/TRIM33 functions as an ubiquitin ligase for the Smad4 signal transducer and antagonizes the Bone Morphogenetic Protein (BMP) signaling network underlying vertebrate dorsal-ventral axis formation. Here, we show that Bonus functions as an agonist of the Decapentaplegic (Dpp) signaling network underlying dorsal-ventral axis formation in flies. The absence of conservation for the roles of Bonus and TIF1-γ/TRIM33 reveals a shift in the dorsal-ventral patterning networks of flies and mice, systems that were previously considered wholly conserved. The shift occurred when the new gene TIF1-γ/TRIM33 replaced the function of the ubiquitin ligase Nedd4L in the lineage leading to vertebrates. Evidence of this replacement is our demonstration that Nedd4 performs the function of TIF1-γ/TRIM33 in flies during dorsal-ventral axis formation. The replacement allowed vertebrate Nedd4L to acquire novel functions as a ubiquitin ligase of vertebrate-specific Smad proteins. Overall our data reveal that the architecture of the Dpp/BMP dorsal-ventral patterning network continued to evolve in the vertebrate lineage, after separation from flies, via the incorporation of new genes. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. The indicative map of the pan-European ecological network in Western Europe : technical background report

    OpenAIRE

    Jongman, R.H.G.; Bouwma, I.M.; Doorn, van, A.M.

    2006-01-01

    The Pan European Ecological Network for Western Europe is the third project in developing the Pan European Ecological Network The objective of the Pan-European Ecological Network is to develop a vision for a coherent network of high value areas for biodiversity, as internationally and nationally protected areas in combination with other suitable habitat areas for long term favourable conservation of Europe’s key ecosystems, habitats and species

  17. A Very Fast and Angular Momentum Conserving Tree Code

    International Nuclear Information System (INIS)

    Marcello, Dominic C.

    2017-01-01

    There are many methods used to compute the classical gravitational field in astrophysical simulation codes. With the exception of the typically impractical method of direct computation, none ensure conservation of angular momentum to machine precision. Under uniform time-stepping, the Cartesian fast multipole method of Dehnen (also known as the very fast tree code) conserves linear momentum to machine precision. We show that it is possible to modify this method in a way that conserves both angular and linear momenta.

  18. A Very Fast and Angular Momentum Conserving Tree Code

    Energy Technology Data Exchange (ETDEWEB)

    Marcello, Dominic C., E-mail: dmarce504@gmail.com [Department of Physics and Astronomy, and Center for Computation and Technology Louisiana State University, Baton Rouge, LA 70803 (United States)

    2017-09-01

    There are many methods used to compute the classical gravitational field in astrophysical simulation codes. With the exception of the typically impractical method of direct computation, none ensure conservation of angular momentum to machine precision. Under uniform time-stepping, the Cartesian fast multipole method of Dehnen (also known as the very fast tree code) conserves linear momentum to machine precision. We show that it is possible to modify this method in a way that conserves both angular and linear momenta.

  19. Conserving critical sites for biodiversity provides disproportionate benefits to people

    DEFF Research Database (Denmark)

    Larsen, Frank Wugt; Turner, Will R.; Brooks, Thomas M.

    2012-01-01

    Protecting natural habitats in priority areas is essential to halt the loss of biodiversity. Yet whether these benefits for biodiversity also yield benefits for human well-being remains controversial. Here we assess the potential human well-being benefits of safeguarding a global network of sites......) benefits to maintenance of human cultural diversity - significantly exceeding those anticipated from randomly selected sites within the same countries and ecoregions. Results suggest that safeguarding sites important for biodiversity conservation provides substantial benefits to human well-being....

  20. Optimal conservation outcomes require both restoration and protection.

    Science.gov (United States)

    Possingham, Hugh P; Bode, Michael; Klein, Carissa J

    2015-01-01

    Conservation outcomes are principally achieved through the protection of intact habitat or the restoration of degraded habitat. Restoration is generally considered a lower priority action than protection because protection is thought to provide superior outcomes, at lower costs, without the time delay required for restoration. Yet while it is broadly accepted that protected intact habitat safeguards more biodiversity and generates greater ecosystem services per unit area than restored habitat, conservation lacks a theory that can coherently compare the relative outcomes of the two actions. We use a dynamic landscape model to integrate these two actions into a unified conservation theory of protection and restoration. Using nonlinear benefit functions, we show that both actions are crucial components of a conservation strategy that seeks to optimise either biodiversity conservation or ecosystem services provision. In contrast to conservation orthodoxy, in some circumstances, restoration should be strongly preferred to protection. The relative priority of protection and restoration depends on their costs and also on the different time lags that are inherent to both protection and restoration. We derive a simple and easy-to-interpret heuristic that integrates these factors into a single equation that applies equally to biodiversity conservation and ecosystem service objectives. We use two examples to illustrate the theory: bird conservation in tropical rainforests and coastal defence provided by mangrove forests.

  1. Optimal conservation outcomes require both restoration and protection.

    Directory of Open Access Journals (Sweden)

    Hugh P Possingham

    2015-01-01

    Full Text Available Conservation outcomes are principally achieved through the protection of intact habitat or the restoration of degraded habitat. Restoration is generally considered a lower priority action than protection because protection is thought to provide superior outcomes, at lower costs, without the time delay required for restoration. Yet while it is broadly accepted that protected intact habitat safeguards more biodiversity and generates greater ecosystem services per unit area than restored habitat, conservation lacks a theory that can coherently compare the relative outcomes of the two actions. We use a dynamic landscape model to integrate these two actions into a unified conservation theory of protection and restoration. Using nonlinear benefit functions, we show that both actions are crucial components of a conservation strategy that seeks to optimise either biodiversity conservation or ecosystem services provision. In contrast to conservation orthodoxy, in some circumstances, restoration should be strongly preferred to protection. The relative priority of protection and restoration depends on their costs and also on the different time lags that are inherent to both protection and restoration. We derive a simple and easy-to-interpret heuristic that integrates these factors into a single equation that applies equally to biodiversity conservation and ecosystem service objectives. We use two examples to illustrate the theory: bird conservation in tropical rainforests and coastal defence provided by mangrove forests.

  2. Energy conservation and efficiency in manufacturing: Employee decisions and actions

    Science.gov (United States)

    Corson, Marla D.

    Energy conservation and intensity reduction efforts are becoming increasingly more prevalent and ultimately necessary, especially for energy-intensive manufacturing companies in particular to stay in business. Typical actions are to change technology, and thus, realize an energy cost savings in overall utilities. However, in today's competitive market, with climate change and other environmental impacts as well, it is necessary for the cost of energy to be valued as a cost of making a product, and thus, managed at the same level as the cost of labor or materials. This research assessed human behavior at the individual and organizational levels both at work and at home that either prompted or prohibited employees from taking daily action to conserve energy or develop greater energy efficient practices. Ultimately, the questions began with questions regarding employee views and knowledge of energy at work and at home and what drives both behaviors toward conservation or efficiency. And, the contribution identifies the key drivers, barriers, and/or incentives that affect those behaviors. The results of this study show that the key driver and motivator for energy conservation both at home and work is cost savings. The study showed that to further motivate individuals to conserve energy at home and work, more knowledge of the impact their actions have or could have as well as tools would be needed. The most poinient aspect of the research was the level of importance placed on energy conservation and the desire to conserve. The feedback given to the open ended questions was quite impressive regarding what employees have done and continue to do particularly within their homes to conserve energy. These findings brought about final recommendations that were in fact not expected but could significantly influence an increase in energy conservation at work by leveraging the existing desire to conserve which is a key component to decision making.

  3. Integrated assessment of exergy, energy and carbon dioxide emissions in an iron and steel industrial network

    International Nuclear Information System (INIS)

    Wu, Junnian; Wang, Ruiqi; Pu, Guangying; Qi, Hang

    2016-01-01

    Highlights: • Exergy, energy and CO_2 emissions assessment of iron and steel industrial network. • Effects of industry symbiosis measures on exergy, energy and CO_2 emissions. • Exploring the environmental impact from exergy losses. • The overall performance indexes are proposed for iron and steel industrial network. • Sinter strand and the wet quenching process have the lowest exergy efficiency. - Abstract: Intensive energy consumption and high pollution emissions in the iron and steel industry have caused problems to the energy system, in the economy, and in the environment. Iron and steel industrial network as an example of energy conservation and emissions reduction, require better analysis and assessment. The present study comprehensively assesses an iron and steel industrial network and its environmental performance with respect to exergy, energy and CO_2 emissions. The results show that the sinter strand needs to be greatly improved and the wet quenching process needs to be completely redesigned. The overall exergy efficiency and energy efficiency can be improved by adopting industrial symbiosis (IS) measures. We found that adjusting the energy structure to use renewable energy and recycling solid waste can greatly reduce CO_2 emissions. Moreover, the maximum exergy losses occurred in the blast furnace with the maximum CO_2 emissions. The iron making plant exerted a strong effect on the environment based on the equivalent CO_2 emission potentials. Many performance indicators of the entire industrial network were also examined in this work. It can be seen that integrated evaluation of energy and CO_2 emissions with exergy is necessary to help to mitigate adverse environmental impacts and more effectively fulfill the goals for energy conservation and emissions reduction.

  4. Gene network analysis shows immune-signaling and ERK1/2 as novel genetic markers for multiple addiction phenotypes: alcohol, smoking and opioid addiction.

    Science.gov (United States)

    Reyes-Gibby, Cielito C; Yuan, Christine; Wang, Jian; Yeung, Sai-Ching J; Shete, Sanjay

    2015-06-05

    Addictions to alcohol and tobacco, known risk factors for cancer, are complex heritable disorders. Addictive behaviors have a bidirectional relationship with pain. We hypothesize that the associations between alcohol, smoking, and opioid addiction observed in cancer patients have a genetic basis. Therefore, using bioinformatics tools, we explored the underlying genetic basis and identified new candidate genes and common biological pathways for smoking, alcohol, and opioid addiction. Literature search showed 56 genes associated with alcohol, smoking and opioid addiction. Using Core Analysis function in Ingenuity Pathway Analysis software, we found that ERK1/2 was strongly interconnected across all three addiction networks. Genes involved in immune signaling pathways were shown across all three networks. Connect function from IPA My Pathway toolbox showed that DRD2 is the gene common to both the list of genetic variations associated with all three addiction phenotypes and the components of the brain neuronal signaling network involved in substance addiction. The top canonical pathways associated with the 56 genes were: 1) calcium signaling, 2) GPCR signaling, 3) cAMP-mediated signaling, 4) GABA receptor signaling, and 5) G-alpha i signaling. Cancer patients are often prescribed opioids for cancer pain thus increasing their risk for opioid abuse and addiction. Our findings provide candidate genes and biological pathways underlying addiction phenotypes, which may be future targets for treatment of addiction. Further study of the variations of the candidate genes could allow physicians to make more informed decisions when treating cancer pain with opioid analgesics.

  5. Cascading Failures and Recovery in Networks of Networks

    Science.gov (United States)

    Havlin, Shlomo

    Network science have been focused on the properties of a single isolated network that does not interact or depends on other networks. In reality, many real-networks, such as power grids, transportation and communication infrastructures interact and depend on other networks. I will present a framework for studying the vulnerability and the recovery of networks of interdependent networks. In interdependent networks, when nodes in one network fail, they cause dependent nodes in other networks to also fail. This is also the case when some nodes like certain locations play a role in two networks -multiplex. This may happen recursively and can lead to a cascade of failures and to a sudden fragmentation of the system. I will present analytical solutions for the critical threshold and the giant component of a network of n interdependent networks. I will show, that the general theory has many novel features that are not present in the classical network theory. When recovery of components is possible global spontaneous recovery of the networks and hysteresis phenomena occur and the theory suggests an optimal repairing strategy of system of systems. I will also show that interdependent networks embedded in space are significantly more vulnerable compared to non embedded networks. In particular, small localized attacks may lead to cascading failures and catastrophic consequences.Thus, analyzing data of real network of networks is highly required to understand the system vulnerability. DTRA, ONR, Israel Science Foundation.

  6. Do Policy Networks lead to Network Governing?

    DEFF Research Database (Denmark)

    Damgaard, Bodil

    This paper challenges the notion that creation of local policy networks necessarily leads to network governing. Through actor-centred case studies in the area of municipally implemented employment policy in Denmark it was found that the local governing mode is determined mainly by the municipality......’s approach to local co-governing as well as by the capacity and interest of key private actors. It is argued that national legislation requesting the creation of local policy networks was not enough to assure network governing and the case studies show that local policy networks may subsist also under...... hierarchical governing modes. Reasons why hierarchical governing modes prevail over network governing in some settings are identified pointing to both actor borne and structural factors. Output indicators of the four cases do not show that a particular governing mode is more efficient in its employment policy...

  7. Conservative interacting particles system with anomalous rate of ergodicity

    OpenAIRE

    Brzeźniak, Zdzislaw; Flandoli, Franco; Neklyudov, Misha; Zegarliński, Boguslaw

    2010-01-01

    We analyze certain conservative interacting particle system and establish ergodicity of the system for a family of invariant measures. Furthermore, we show that convergence rate to equilibrium is exponential. This result is of interest because it presents counterexample to the standard assumption of physicists that conservative system implies polynomial rate of convergence.

  8. Research priorities for conservation and natural resource management in Oceania's small-island developing states.

    Science.gov (United States)

    Weeks, R; Adams, V M

    2018-02-01

    For conservation science to effectively inform management, research must focus on creating the scientific knowledge required to solve conservation problems. We identified research questions that, if answered, would increase the effectiveness of conservation and natural resource management practice and policy in Oceania's small-island developing states. We asked conservation professionals from academia, governmental, and nongovernmental organizations across the region to propose such questions and then identify which were of high priority in an online survey. We compared the high-priority questions with research questions identified globally and for other regions. Of 270 questions proposed by respondents, 38 were considered high priority, including: What are the highest priority areas for conservation in the face of increasing resource demand and climate change? How should marine protected areas be networked to account for connectivity and climate change? What are the most effective fisheries management policies that contribute to sustainable coral reef fisheries? High-priority questions related to the particular challenges of undertaking conservation on small-island developing states and the need for a research agenda that is responsive to the sociocultural context of Oceania. Research priorities for Oceania relative to elsewhere were broadly similar but differed in specific issues relevant to particular conservation contexts. These differences emphasize the importance of involving local practitioners in the identification of research priorities. Priorities were reasonably well aligned among sectoral groups. Only a few questions were widely considered answered, which may indicate a smaller-than-expected knowledge-action gap. We believe these questions can be used to strengthen research collaborations between scientists and practitioners working to further conservation and natural resource management in this region. © 2017 The Authors. Conservation Biology

  9. Googling trends in conservation biology.

    Science.gov (United States)

    Proulx, Raphaël; Massicotte, Philippe; Pépino, Marc

    2014-02-01

    Web-crawling approaches, that is, automated programs data mining the internet to obtain information about a particular process, have recently been proposed for monitoring early signs of ecosystem degradation or for establishing crop calendars. However, lack of a clear conceptual and methodological framework has prevented the development of such approaches within the field of conservation biology. Our objective was to illustrate how Google Trends, a freely accessible web-crawling engine, can be used to track changes in timing of biological processes, spatial distribution of invasive species, and level of public awareness about key conservation issues. Google Trends returns the number of internet searches that were made for a keyword in a given region of the world over a defined period. Using data retrieved online for 13 countries, we exemplify how Google Trends can be used to study the timing of biological processes, such as the seasonal recurrence of pollen release or mosquito outbreaks across a latitudinal gradient. We mapped the spatial extent of results from Google Trends for 5 invasive species in the United States and found geographic patterns in invasions that are consistent with their coarse-grained distribution at state levels. From 2004 through 2012, Google Trends showed that the level of public interest and awareness about conservation issues related to ecosystem services, biodiversity, and climate change increased, decreased, and followed both trends, respectively. Finally, to further the development of research approaches at the interface of conservation biology, collective knowledge, and environmental management, we developed an algorithm that allows the rapid retrieval of Google Trends data. © 2013 Society for Conservation Biology.

  10. A homologous mapping method for three-dimensional reconstruction of protein networks reveals disease-associated mutations.

    Science.gov (United States)

    Huang, Sing-Han; Lo, Yu-Shu; Luo, Yong-Chun; Tseng, Yu-Yao; Yang, Jinn-Moon

    2018-03-19

    One of the crucial steps toward understanding the associations among molecular interactions, pathways, and diseases in a cell is to investigate detailed atomic protein-protein interactions (PPIs) in the structural interactome. Despite the availability of large-scale methods for analyzing PPI networks, these methods often focused on PPI networks using genome-scale data and/or known experimental PPIs. However, these methods are unable to provide structurally resolved interaction residues and their conservations in PPI networks. Here, we reconstructed a human three-dimensional (3D) structural PPI network (hDiSNet) with the detailed atomic binding models and disease-associated mutations by enhancing our PPI families and 3D-domain interologs from 60,618 structural complexes and complete genome database with 6,352,363 protein sequences across 2274 species. hDiSNet is a scale-free network (γ = 2.05), which consists of 5177 proteins and 19,239 PPIs with 5843 mutations. These 19,239 structurally resolved PPIs not only expanded the number of PPIs compared to present structural PPI network, but also achieved higher agreement with gene ontology similarities and higher co-expression correlation than the ones of 181,868 experimental PPIs recorded in public databases. Among 5843 mutations, 1653 and 790 mutations involved in interacting domains and contacting residues, respectively, are highly related to diseases. Our hDiSNet can provide detailed atomic interactions of human disease and their associated proteins with mutations. Our results show that the disease-related mutations are often located at the contacting residues forming the hydrogen bonds or conserved in the PPI family. In addition, hDiSNet provides the insights of the FGFR (EGFR)-MAPK pathway for interpreting the mechanisms of breast cancer and ErbB signaling pathway in brain cancer. Our results demonstrate that hDiSNet can explore structural-based interactions insights for understanding the mechanisms of disease

  11. Effects of cost metric on cost-effectiveness of protected-area network design in urban landscapes.

    Science.gov (United States)

    Burkhalter, J C; Lockwood, J L; Maslo, B; Fenn, K H; Leu, K

    2016-04-01

    A common goal in conservation planning is to acquire areas that are critical to realizing biodiversity goals in the most cost-effective manner. The way monetary acquisition costs are represented in such planning is an understudied but vital component to realizing cost efficiencies. We sought to design a protected-area network within a forested urban region that would protect 17 birds of conservation concern. We compared the total costs and spatial structure of the optimal protected-area networks produced using three acquisition-cost surrogates (area, agricultural land value, and tax-assessed land value). Using the tax-assessed land values there was a 73% and 78% cost savings relative to networks derived using area or agricultural land value, respectively. This cost reduction was due to the considerable heterogeneity in acquisition costs revealed in tax-assessed land values, especially for small land parcels, and the corresponding ability of the optimization algorithm to identify lower-cost parcels for inclusion that had equal value to our target species. Tax-assessed land values also reflected the strong spatial differences in acquisition costs (US$0.33/m(2)-$55/m(2)) and thus allowed the algorithm to avoid inclusion of high-cost parcels when possible. Our results add to a nascent but growing literature that suggests conservation planners must consider the cost surrogate they use when designing protected-area networks. We suggest that choosing cost surrogates that capture spatial- and size-dependent heterogeneity in acquisition costs may be relevant to establishing protected areas in urbanizing ecosystems. © 2015 Society for Conservation Biology.

  12. Discontinuous Galerkin Method for Hyperbolic Conservation Laws

    KAUST Repository

    Mousikou, Ioanna

    2016-11-11

    Hyperbolic conservation laws form a special class of partial differential equations. They describe phenomena that involve conserved quantities and their solutions show discontinuities which reflect the formation of shock waves. We consider one-dimensional systems of hyperbolic conservation laws and produce approximations using finite difference, finite volume and finite element methods. Due to stability issues of classical finite element methods for hyperbolic conservation laws, we study the discontinuous Galerkin method, which was recently introduced. The method involves completely discontinuous basis functions across each element and it can be considered as a combination of finite volume and finite element methods. We illustrate the implementation of discontinuous Galerkin method using Legendre polynomials, in case of scalar equations and in case of quasi-linear systems, and we review important theoretical results about stability and convergence of the method. The applications of finite volume and discontinuous Galerkin methods to linear and non-linear scalar equations, as well as to the system of elastodynamics, are exhibited.

  13. Discontinuous Galerkin Method for Hyperbolic Conservation Laws

    KAUST Repository

    Mousikou, Ioanna

    2016-01-01

    Hyperbolic conservation laws form a special class of partial differential equations. They describe phenomena that involve conserved quantities and their solutions show discontinuities which reflect the formation of shock waves. We consider one-dimensional systems of hyperbolic conservation laws and produce approximations using finite difference, finite volume and finite element methods. Due to stability issues of classical finite element methods for hyperbolic conservation laws, we study the discontinuous Galerkin method, which was recently introduced. The method involves completely discontinuous basis functions across each element and it can be considered as a combination of finite volume and finite element methods. We illustrate the implementation of discontinuous Galerkin method using Legendre polynomials, in case of scalar equations and in case of quasi-linear systems, and we review important theoretical results about stability and convergence of the method. The applications of finite volume and discontinuous Galerkin methods to linear and non-linear scalar equations, as well as to the system of elastodynamics, are exhibited.

  14. A conserved Oct4/POUV-dependent network links adhesion and migration to progenitor maintenance

    DEFF Research Database (Denmark)

    Livigni, Alessandra; Peradziryi, Hanna; Sharov, Alexei A

    2013-01-01

    BACKGROUND: The class V POU domain transcription factor Oct4 (Pou5f1) is a pivotal regulator of embryonic stem cell (ESC) self-renewal and reprogramming of somatic cells to induced pluripotent stem (iPS) cells. Oct4 is also an important evolutionarily conserved regulator of progenitor cell differ...

  15. Conservation of transcription factor binding events predicts gene expression across species

    Science.gov (United States)

    Hemberg, Martin; Kreiman, Gabriel

    2011-01-01

    Recent technological advances have made it possible to determine the genome-wide binding sites of transcription factors (TFs). Comparisons across species have suggested a relatively low degree of evolutionary conservation of experimentally defined TF binding events (TFBEs). Using binding data for six different TFs in hepatocytes and embryonic stem cells from human and mouse, we demonstrate that evolutionary conservation of TFBEs within orthologous proximal promoters is closely linked to function, defined as expression of the target genes. We show that (i) there is a significantly higher degree of conservation of TFBEs when the target gene is expressed in both species; (ii) there is increased conservation of binding events for groups of TFs compared to individual TFs; and (iii) conserved TFBEs have a greater impact on the expression of their target genes than non-conserved ones. These results link conservation of structural elements (TFBEs) to conservation of function (gene expression) and suggest a higher degree of functional conservation than implied by previous studies. PMID:21622661

  16. Diffusion Processes Satisfying a Conservation Law Constraint

    Directory of Open Access Journals (Sweden)

    J. Bakosi

    2014-01-01

    Full Text Available We investigate coupled stochastic differential equations governing N nonnegative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires a set of fluctuating variables to be nonnegative and (if appropriately normalized sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the nonnegativity and the unit-sum conservation law constraints are satisfied as the variables evolve in time. We investigate the consequences of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have diffusion terms that are coupled and nonlinear. The set of constraints developed enables the development of statistical representations of fluctuating variables satisfying a conservation law. We exemplify the results with the bivariate beta process and the multivariate Wright-Fisher, Dirichlet, and Lochner’s generalized Dirichlet processes.

  17. Profiling of proteolytic enzymes in the gut of the tick Ixodes ricinus reveals an evolutionarily conserved network of aspartic and cysteine peptidases

    Directory of Open Access Journals (Sweden)

    Mareš Michael

    2008-03-01

    Full Text Available Abstract Background Ticks are vectors for a variety of viral, bacterial and parasitic diseases in human and domestic animals. To survive and reproduce ticks feed on host blood, yet our understanding of the intestinal proteolytic machinery used to derive absorbable nutrients from the blood meal is poor. Intestinal digestive processes are limiting factors for pathogen transmission since the tick gut presents the primary site of infection. Moreover, digestive enzymes may find practical application as anti-tick vaccine targets. Results Using the hard tick, Ixodes ricinus, we performed a functional activity scan of the peptidase complement in gut tissue extracts that demonstrated the presence of five types of peptidases of the cysteine and aspartic classes. We followed up with genetic screens of gut-derived cDNA to identify and clone genes encoding the cysteine peptidases cathepsins B, L and C, an asparaginyl endopeptidase (legumain, and the aspartic peptidase, cathepsin D. By RT-PCR, expression of asparaginyl endopeptidase and cathepsins B and D was restricted to gut tissue and to those developmental stages feeding on blood. Conclusion Overall, our results demonstrate the presence of a network of cysteine and aspartic peptidases that conceivably operates to digest host blood proteins in a concerted manner. Significantly, the peptidase components of this digestive network are orthologous to those described in other parasites, including nematodes and flatworms. Accordingly, the present data and those available for other tick species support the notion of an evolutionary conservation of a cysteine/aspartic peptidase system for digestion that includes ticks, but differs from that of insects relying on serine peptidases.

  18. Weighted Scale-Free Network Properties of Ecological Network

    International Nuclear Information System (INIS)

    Lee, Jae Woo; Maeng, Seong Eun

    2013-01-01

    We investigate the scale-free network properties of the bipartite ecological network, in particular, the plant-pollinator network. In plant-pollinator network, the pollinators visit the plant to get the nectars. In contrast to the other complex network, the plant-pollinator network has not only the trophic relationships among the interacting partners but also the complexities of the coevolutionary effects. The interactions between the plant and pollinators are beneficial relations. The plant-pollinator network is a bipartite and weighted network. The networks have two types of the nodes: plant and pollinator. We consider the visiting frequency of a pollinator to a plant as the weighting value of the link. We defined the strength of a node as the sum of the weighting value of the links. We reported the cumulative distribution function (CDF) of the degree and the strength of the plant-pollinator network. The CDF of the plants followed stretched exponential functions for both degree and strength, but the CDF of the pollinators showed the power law for both degree and strength. The average strength of the links showed the nonlinear dependence on the degree of the networks.

  19. The Evolution of Wikipedia’s Norm Network

    Directory of Open Access Journals (Sweden)

    Bradi Heaberlin

    2016-04-01

    Full Text Available Social norms have traditionally been difficult to quantify. In any particular society, their sheer number and complex interdependencies often limit a system-level analysis. One exception is that of the network of norms that sustain the online Wikipedia community. We study the fifteen-year evolution of this network using the interconnected set of pages that establish, describe, and interpret the community’s norms. Despite Wikipedia’s reputation for ad hoc governance, we find that its normative evolution is highly conservative. The earliest users create norms that both dominate the network and persist over time. These core norms govern both content and interpersonal interactions using abstract principles such as neutrality, verifiability, and assume good faith. As the network grows, norm neighborhoods decouple topologically from each other, while increasing in semantic coherence. Taken together, these results suggest that the evolution of Wikipedia’s norm network is akin to bureaucratic systems that predate the information age.

  20. Balanced Cluster Head Selection Based on Modified k-Means in a Distributed Wireless Sensor Network

    OpenAIRE

    Periyasamy, Sasikumar; Khara, Sibaram; Thangavelu, Shankar

    2016-01-01

    A major problem with Wireless Sensor Networks (WSNs) is the maximization of effective network lifetime through minimization of energy usage in the network nodes. A modified k-means (Mk-means) algorithm for clustering was proposed which includes three cluster heads (simultaneously chosen) for each cluster. These cluster heads (CHs) use a load sharing mechanism to rotate as the active cluster head, which conserves residual energy of the nodes, thereby extending network lifetime. Moreover, it re...

  1. Optimal fire histories for biodiversity conservation.

    Science.gov (United States)

    Kelly, Luke T; Bennett, Andrew F; Clarke, Michael F; McCarthy, Michael A

    2015-04-01

    Fire is used as a management tool for biodiversity conservation worldwide. A common objective is to avoid population extinctions due to inappropriate fire regimes. However, in many ecosystems, it is unclear what mix of fire histories will achieve this goal. We determined the optimal fire history of a given area for biological conservation with a method that links tools from 3 fields of research: species distribution modeling, composite indices of biodiversity, and decision science. We based our case study on extensive field surveys of birds, reptiles, and mammals in fire-prone semi-arid Australia. First, we developed statistical models of species' responses to fire history. Second, we determined the optimal allocation of successional states in a given area, based on the geometric mean of species relative abundance. Finally, we showed how conservation targets based on this index can be incorporated into a decision-making framework for fire management. Pyrodiversity per se did not necessarily promote vertebrate biodiversity. Maximizing pyrodiversity by having an even allocation of successional states did not maximize the geometric mean abundance of bird species. Older vegetation was disproportionately important for the conservation of birds, reptiles, and small mammals. Because our method defines fire management objectives based on the habitat requirements of multiple species in the community, it could be used widely to maximize biodiversity in fire-prone ecosystems. © 2014 Society for Conservation Biology.

  2. Synchronization propensity in networks of dynamical systems: A purely topological indicator

    OpenAIRE

    Fasani, S.; Rinaldi, S.

    2012-01-01

    Synchronization in networks of identical dynamical systems is enhanced by the number of manifolds in which synchrony of groups of systems is conserved or reinforced. Since the number of these invariant manifolds depends only on the coupling architecture of the network, it can be proposed as a purely topological indicator of synchronization propensity. The proposal is empirically validated through the detailed study of an ecological application.

  3. Bainbridge Energy Challenge. Energy efficiency and conservation block grant (EECBG) - Better buildings neighborhood program. Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, Yvonne X.

    2014-02-14

    RePower Bainbridge and Bremerton (RePower) is a residential energy-efficiency and conservation program designed to foster a sustainable, clean, and renewable energy economy. The program was a 3.5 year effort in the cities of Bainbridge Island and Bremerton, Washington, to conserve and reduce energy use, establish a trained home performance trade ally network, and create local jobs. RePower was funded through a $4.8 million grant from the US Department of Energy, Better Buildings Program. The grant’s performance period was August 1, 2010 through March 30, 2014.

  4. Restricted-range fishes and the conservation of Brazilian freshwaters.

    Directory of Open Access Journals (Sweden)

    Cristiano Nogueira

    Full Text Available BACKGROUND: Freshwaters are the most threatened ecosystems on earth. Although recent assessments provide data on global priority regions for freshwater conservation, local scale priorities remain unknown. Refining the scale of global biodiversity assessments (both at terrestrial and freshwater realms and translating these into conservation priorities on the ground remains a major challenge to biodiversity science, and depends directly on species occurrence data of high taxonomic and geographic resolution. Brazil harbors the richest freshwater ichthyofauna in the world, but knowledge on endemic areas and conservation in Brazilian rivers is still scarce. METHODOLOGY/PRINCIPAL FINDINGS: Using data on environmental threats and revised species distribution data we detect and delineate 540 small watershed areas harboring 819 restricted-range fishes in Brazil. Many of these areas are already highly threatened, as 159 (29% watersheds have lost more than 70% of their original vegetation cover, and only 141 (26% show significant overlap with formally protected areas or indigenous lands. We detected 220 (40% critical watersheds overlapping hydroelectric dams or showing both poor formal protection and widespread habitat loss; these sites harbor 344 endemic fish species that may face extinction if no conservation action is in place in the near future. CONCLUSIONS/SIGNIFICANCE: We provide the first analysis of site-scale conservation priorities in the richest freshwater ecosystems of the globe. Our results corroborate the hypothesis that freshwater biodiversity has been neglected in former conservation assessments. The study provides a simple and straightforward method for detecting freshwater priority areas based on endemism and threat, and represents a starting point for integrating freshwater and terrestrial conservation in representative and biogeographically consistent site-scale conservation strategies, that may be scaled-up following naturally linked

  5. Nonlinear adaptive PID control for greenhouse environment based on RBF network.

    Science.gov (United States)

    Zeng, Songwei; Hu, Haigen; Xu, Lihong; Li, Guanghui

    2012-01-01

    This paper presents a hybrid control strategy, combining Radial Basis Function (RBF) network with conventional proportional, integral, and derivative (PID) controllers, for the greenhouse climate control. A model of nonlinear conservation laws of enthalpy and matter between numerous system variables affecting the greenhouse climate is formulated. RBF network is used to tune and identify all PID gain parameters online and adaptively. The presented Neuro-PID control scheme is validated through simulations of set-point tracking and disturbance rejection. We compare the proposed adaptive online tuning method with the offline tuning scheme that employs Genetic Algorithm (GA) to search the optimal gain parameters. The results show that the proposed strategy has good adaptability, strong robustness and real-time performance while achieving satisfactory control performance for the complex and nonlinear greenhouse climate control system, and it may provide a valuable reference to formulate environmental control strategies for actual application in greenhouse production.

  6. Reducing agrochemical use for nature conservation by Italian olive farmers : an evaluation of public and private governance strategies

    NARCIS (Netherlands)

    Giomi, Tatiyana; Runhaar, Piety; Runhaar, Hens

    2018-01-01

    A variety of public policies and private strategies have been implemented to stimulate farmers to implement nature conservation measures. Examples include publicly funded agri-environment schemes (AES) but also eco-labels and Alternative Food Networks; strategies that have been implemented in

  7. Reducing agrochemical use for nature conservation by Italian olive farmers: an evaluation of public and private governance strategies

    NARCIS (Netherlands)

    Giomi, Tatiyana; Runhaar, Piety; Runhaar, Hens

    2018-01-01

    A variety of public policies and private strategies have been implemented to stimulate farmers to implement nature conservation measures. Examples include publicly funded agri-environment schemes (AES) but also eco-labels and Alternative Food Networks; strategies that have been implemented in

  8. Conservation without borders: building communication and action across disciplinary boundaries for effective conservation.

    Science.gov (United States)

    Margles, Shawn W; Peterson, Richard B; Ervin, Jamison; Kaplin, Beth A

    2010-01-01

    Interdisciplinary approaches to conservation research and environmental management continue to garner interest among practitioners, academics, and students. Yet, cases of practitioners and researchers from different disciplines successfully working in concert towards an integrated conservation approach are rare. What is preventing practitioners of multiple disciplines from harmoniously working together? Why are practitioners and academics struggling to apply their graduate training to real world conservation? What is preventing the benefits of cooperation and partnerships between different disciplines addressing conservation from being realized? This special issue "Conservation without Borders: Building Communication and Action across Disciplinary Boundaries for Effective Conservation" asks readers to consider the numerous interpretations and implications of the phrase "Conservation without Borders" and to reflect on how different academic and disciplinary lenses can contribute to a more integrated approach to tackling conservation challenges. The articles that comprise this special issue offer readers insights into the ways in which different disciplines view conservation work and interdisciplinary approaches to environmental problems. Bringing these perspectives and approaches together in one place is a step towards improving communication across disciplines for the purpose of achieving more successful biodiversity conservation.

  9. Reaching people with energy conservation information: four statewide residential case studies

    Energy Technology Data Exchange (ETDEWEB)

    Peelle, E.; Braid, R.B.; Jones, D.W.; Reed, J.H.

    1983-09-01

    Four state residential energy conservation programs are reviewed in terms of their origins, evolutions, purposes and goals, administration, organization, and outcomes. The four programs chosen were selected from among 30 nominated by state energy offices and regional Department of Energy personnel as being illustrative in terms of organization and/or outcomes. While intended primarily for state-level program managers and staff, the profiles of programs, conclusions, and recommendations should be useful to anyone interested in developing viable, action-oriented conservation programs. The four case studies included Oregon's Master Conserver program, Oklahoma's energy education project for low-income and elderly families, Virginia's workshops for heating dealers service and contractors, and Maine's three energy education projects - the Energy Bus, Energy Conservation Month, and the Home Energy Check-up. All four programs utilized Energy Extension Service (EES) funds from the federal government, and three were directly managed through the state EES organization. The findings of the study indicate that these programs (1) had flexibility to experiment, iterate, and reorganize as a result of their initial experiences, (2) made extensive use of networking to involve local groups in program delivery, (3) employed a large variety of delivery methods, and (4) made substantial efforts to tailor literature and handouts to the target audiences.

  10. Survey of local and global biological network alignment: the need to reconcile the two sides of the same coin.

    Science.gov (United States)

    Guzzi, Pietro Hiram; Milenković, Tijana

    2017-01-05

    Analogous to genomic sequence alignment that allows for across-species transfer of biological knowledge between conserved sequence regions, biological network alignment can be used to guide the knowledge transfer between conserved regions of molecular networks of different species. Hence, biological network alignment can be used to redefine the traditional notion of a sequence-based homology to a new notion of network-based homology. Analogous to genomic sequence alignment, there exist local and global biological network alignments. Here, we survey prominent and recent computational approaches of each network alignment type and discuss their (dis)advantages. Then, as it was recently shown that the two approach types are complementary, in the sense that they capture different slices of cellular functioning, we discuss the need to reconcile the two network alignment types and present a recent first step in this direction. We conclude with some open research problems on this topic and comment on the usefulness of network alignment in other domains besides computational biology. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. 78 FR 73589 - Energy Conservation Program: Energy Conservation Standards for Commercial and Industrial Electric...

    Science.gov (United States)

    2013-12-06

    ... Conservation Program: Energy Conservation Standards for Commercial and Industrial Electric Motors; Proposed... Conservation Program: Energy Conservation Standards for Commercial and Industrial Electric Motors AGENCY... proposes energy conservation standards for a number of different groups of electric motors that DOE has not...

  12. Habitat evaluation of wild Amur tiger (Panthera tigris altaica) and conservation priority setting in north-eastern China.

    Science.gov (United States)

    Xiaofeng, Luan; Yi, Qu; Diqiang, Li; Shirong, Liu; Xiulei, Wang; Bo, Wu; Chunquan, Zhu

    2011-01-01

    The Amur Tiger (Panthera tigris altaica) is one of the world's most endangered species. Recently, habitat fragmentation, food scarcity and human hunting have drastically reduced the population size and distribution areas of Amur tigers in the wild, leaving them on the verge of extinction. Presently, they are only found in the north-eastern part of China. In this study, we developed a reference framework using methods and technologies of analytic hierarchy process (AHP), remote sensing (RS), geographic information system (GIS), GAP analysis and Natural Break (Jenks) classification to evaluate the habitat and to set the conservation priorities for Amur tigers in eastern areas of Heilongjiang and Jilin Provinces of northeast China. We proposed a Habitat Suitability Index (HSI) incorporating 7 factors covering natural conditions and human disturbance. Based on the HSI values, the suitability was classified into five levels from the most to not suitable. Finally, according to results of GAP analysis, we identified six conservation priorities and designed a conservation landscape incorporating four new nature reserves, enlarging two existing ones, and creating four linkages for Amur tigers in northeast China. The case study showed that the core habitats (the most suitable and highly suitable habitats) identified for Amur tigers covered 35,547 km(2), accounting for approximately 26.71% of the total study area (1,33,093 km(2)). However, existing nature reserves protected only (7124 km(2) or) 20.04% of the identified core habitats. Thus, enlargement of current reserves is necessary and urgent for the tiger's conservation and restoration. Moreover, the establishment of wildlife corridors linking core habitats will provide an efficient reserve network for tiger conservation to maintain the evolutionary potential of Amur tigers facing environmental changes. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Building ties: social capital network analysis of a forest community in a biosphere reserve in Chiapas, Mexico

    Directory of Open Access Journals (Sweden)

    Luis Rico García-Amado

    2012-09-01

    Full Text Available Governance of the commons depends on the capacity to generate collective action. Networks and rules that foster that collective action have been defined as social capital. However, their causal link is still not fully understood. We use social network analysis to assess social capital, decision-making, and collective action in a forest-based common pool resource management in La Sepultura Biosphere Reserve (Chiapas, Mexico. Our research analyzes the productive networks and the evolution of coffee groups in one community. The network shows some centrality, with richer landholders tending to occupy core positions and poorer landless peasants occupying peripheral ones. This has fostered the community's environmentally oriented development but has also caused internal conflicts. Market requirements have shaped different but complementary productive networks, where organic coffee commercialization is the main source of bridging ties, which has resulted in more connectivity and resilience. Conservation attitudes, along with the institutional setting of the community, have promoted collective action. The unresolved conflicts, however, still leave some concerns about governance in the future.

  14. Identifying temporal bottlenecks for the conservation of large-bodied fishes: Lake Sturgeon (Acipenser fulvescens show highly restricted movement and habitat use over-winter

    Directory of Open Access Journals (Sweden)

    Donnette Thayer

    2017-04-01

    Full Text Available The relationship between species’ size and home range size has been well studied. In practice, home range may provide a good surrogate of broad spatial coverage needed for species conservation, however, many species can show restricted movement during critical life stages, such as breeding and over-wintering. This suggests the existence of either a behavioral or habitat mediated ‘temporal bottleneck,’ where restricted or sedentary movement can make populations more susceptible to harm during specific life stages. Here, we study over-winter movement and habitat use of Lake Sturgeon (Acipenser fulvescens, the largest freshwater fish in North America. We monitored over-winter movement of 86 fish using a hydro-acoustic receiver array in the South Saskatchewan River, Canada. Overall, 20 fish remained within our study system throughout the winter. Lake Sturgeon showed strong aggregation and sedentary movement over-winter, demonstrating a temporal bottleneck. Movement was highly restricted during ice-on periods (ranging from 0.9 km/day in November and April to 0.2 km/day in mid-November to mid-March, with Lake Sturgeon seeking deeper, slower pools. We also show that Lake Sturgeon have strong aggregation behavior, where distance to conspecifics decreased (from 575 to 313 m in preparation for and during ice-on periods. Although the Lake Sturgeon we studied had access to 1100 kilometers of unfragmented riverine habitat, we show that during the over-winter period Lake Sturgeon utilized a single, deep pool (<0.1% of available habitat. The temporal discrepancy between mobile and sedentary behaviors in Lake Sturgeon suggest adaptive management is needed with more localized focus during periods of temporal bottlenecks, even for large-bodied species.

  15. Research as an integral part of conservation-restoration education

    DEFF Research Database (Denmark)

    Andersen, Cecil Krarup; Larsen, René

    2017-01-01

    In the present paper we focus on the necessity of conservators-restorers to be equipped with scientific research tools such as observation skills from the beginning and throughout their education. We exemplify the necessity of this with two cases from the applied conservation-restoration practice...... in parchment and wax-resin lining of paintings, respectively, and show that research tools constitute an essential precondition not only for practicing scientific research but also for the performance of a number of other activities in the professional life of a conservator-restorer....

  16. Unified Alignment of Protein-Protein Interaction Networks.

    Science.gov (United States)

    Malod-Dognin, Noël; Ban, Kristina; Pržulj, Nataša

    2017-04-19

    Paralleling the increasing availability of protein-protein interaction (PPI) network data, several network alignment methods have been proposed. Network alignments have been used to uncover functionally conserved network parts and to transfer annotations. However, due to the computational intractability of the network alignment problem, aligners are heuristics providing divergent solutions and no consensus exists on a gold standard, or which scoring scheme should be used to evaluate them. We comprehensively evaluate the alignment scoring schemes and global network aligners on large scale PPI data and observe that three methods, HUBALIGN, L-GRAAL and NATALIE, regularly produce the most topologically and biologically coherent alignments. We study the collective behaviour of network aligners and observe that PPI networks are almost entirely aligned with a handful of aligners that we unify into a new tool, Ulign. Ulign enables complete alignment of two networks, which traditional global and local aligners fail to do. Also, multiple mappings of Ulign define biologically relevant soft clusterings of proteins in PPI networks, which may be used for refining the transfer of annotations across networks. Hence, PPI networks are already well investigated by current aligners, so to gain additional biological insights, a paradigm shift is needed. We propose such a shift come from aligning all available data types collectively rather than any particular data type in isolation from others.

  17. Conservation of myeloid surface antigens on primate granulocytes.

    Science.gov (United States)

    Letvin, N L; Todd, R F; Palley, L S; Schlossman, S F; Griffin, J D

    1983-02-01

    Monoclonal antibodies reactive with myeloid cell surface antigens were used to study evolutionary changes in granulocyte surface antigens from primate species. Certain of these granulocyte membrane antigens are conserved in phylogenetically distant species, indicating the potential functional importance of these structures. The degree of conservation of these antigens reflects the phylogenetic relationship between primate species. Furthermore, species of the same genus show similar patterns of binding to this panel of anti-human myeloid antibodies. This finding of conserved granulocyte surface antigens suggests that non-human primates may provide a model system for exploring uses of monoclonal antibodies in the treatment of human myeloid disorders.

  18. Deterministic bound for avionics switched networks according to networking features using network calculus

    Directory of Open Access Journals (Sweden)

    Feng HE

    2017-12-01

    Full Text Available The state of the art avionics system adopts switched networks for airborne communications. A major concern in the design of the networks is the end-to-end guarantee ability. Analytic methods have been developed to compute the worst-case delays according to the detailed configurations of flows and networks within avionics context, such as network calculus and trajectory approach. It still lacks a relevant method to make a rapid performance estimation according to some typically switched networking features, such as networking scale, bandwidth utilization and average flow rate. The goal of this paper is to establish a deterministic upper bound analysis method by using these networking features instead of the complete network configurations. Two deterministic upper bounds are proposed from network calculus perspective: one is for a basic estimation, and another just shows the benefits from grouping strategy. Besides, a mathematic expression for grouping ability is established based on the concept of network connecting degree, which illustrates the possibly minimal grouping benefit. For a fully connected network with 4 switches and 12 end systems, the grouping ability coming from grouping strategy is 15–20%, which just coincides with the statistical data (18–22% from the actual grouping advantage. Compared with the complete network calculus analysis method for individual flows, the effectiveness of the two deterministic upper bounds is no less than 38% even with remarkably varied packet lengths. Finally, the paper illustrates the design process for an industrial Avionics Full DupleX switched Ethernet (AFDX networking case according to the two deterministic upper bounds and shows that a better control for network connecting, when designing a switched network, can improve the worst-case delays dramatically. Keywords: Deterministic bound, Grouping ability, Network calculus, Networking features, Switched networks

  19. Big biology meets microclimatology: defining thermal niches of ectotherms at landscape scales for conservation planning.

    Science.gov (United States)

    Isaak, Daniel J; Wenger, Seth J; Young, Michael K

    2017-04-01

    Temperature profoundly affects ecology, a fact ever more evident as the ability to measure thermal environments increases and global changes alter these environments. The spatial structure of thermalscapes is especially relevant to the distribution and abundance of ectothermic organisms, but the ability to describe biothermal relationships at extents and grains relevant to conservation planning has been limited by small or sparse data sets. Here, we combine a large occurrence database of >23 000 aquatic species surveys with stream microclimate scenarios supported by an equally large temperature database for a 149 000-km mountain stream network to describe thermal relationships for 14 fish and amphibian species. Species occurrence probabilities peaked across a wide range of temperatures (7.0-18.8°C) but distinct warm- or cold-edge distribution boundaries were apparent for all species and represented environments where populations may be most sensitive to thermal changes. Warm-edge boundary temperatures for a native species of conservation concern were used with geospatial data sets and a habitat occupancy model to highlight subsets of the network where conservation measures could benefit local populations by maintaining cool temperatures. Linking that strategic approach to local estimates of habitat impairment remains a key challenge but is also an opportunity to build relationships and develop synergies between the research, management, and regulatory communities. As with any data mining or species distribution modeling exercise, care is required in analysis and interpretation of results, but the use of large biological data sets with accurate microclimate scenarios can provide valuable information about the thermal ecology of many ectotherms and a spatially explicit way of guiding conservation investments. © 2017 by the Ecological Society of America.

  20. Fixism and conservation science.

    Science.gov (United States)

    Robert, Alexandre; Fontaine, Colin; Veron, Simon; Monnet, Anne-Christine; Legrand, Marine; Clavel, Joanne; Chantepie, Stéphane; Couvet, Denis; Ducarme, Frédéric; Fontaine, Benoît; Jiguet, Frédéric; le Viol, Isabelle; Rolland, Jonathan; Sarrazin, François; Teplitsky, Céline; Mouchet, Maud

    2017-08-01

    The field of biodiversity conservation has recently been criticized as relying on a fixist view of the living world in which existing species constitute at the same time targets of conservation efforts and static states of reference, which is in apparent disagreement with evolutionary dynamics. We reviewed the prominent role of species as conservation units and the common benchmark approach to conservation that aims to use past biodiversity as a reference to conserve current biodiversity. We found that the species approach is justified by the discrepancy between the time scales of macroevolution and human influence and that biodiversity benchmarks are based on reference processes rather than fixed reference states. Overall, we argue that the ethical and theoretical frameworks underlying conservation research are based on macroevolutionary processes, such as extinction dynamics. Current species, phylogenetic, community, and functional conservation approaches constitute short-term responses to short-term human effects on these reference processes, and these approaches are consistent with evolutionary principles. © 2016 Society for Conservation Biology.

  1. Effectiveness of amphibians as biodiversity surrogates in pond conservation.

    Science.gov (United States)

    Ilg, Christiane; Oertli, Beat

    2017-04-01

    Amphibian decline has led to worldwide conservation efforts, including the identification and designation of sites for their protection. These sites could also play an important role in the conservation of other freshwater taxa. In 89 ponds in Switzerland, we assessed the effectiveness of amphibians as a surrogate for 4 taxonomic groups that occur in the same freshwater ecosystems as amphibians: dragonflies, aquatic beetles, aquatic gastropods, and aquatic plants. The ponds were all of high value for amphibian conservation. Cross-taxon correlations were tested for species richness and conservation value, and Mantel tests were used to investigate community congruence. Species richness, conservation value, and community composition of amphibians were weakly congruent with these measures for the other taxonomic groups. Paired comparisons for the 5 groups considered showed that for each metric, amphibians had the lowest degree of congruence. Our results imply that site designation for amphibian conservation will not necessarily provide protection for freshwater biodiversity as a whole. To provide adequate protection for freshwater species, we recommend other taxonomic groups be considered in addition to amphibians in the prioritization and site designation process. © 2016 Society for Conservation Biology.

  2. Oxytocin and vasopressin neural networks: Implications for social behavioral diversity and translational neuroscience.

    Science.gov (United States)

    Johnson, Zachary V; Young, Larry J

    2017-05-01

    Oxytocin- and vasopressin-related systems are present in invertebrate and vertebrate bilaterian animals, including humans, and exhibit conserved neuroanatomical and functional properties. In vertebrates, these systems innervate conserved neural networks that regulate social learning and behavior, including conspecific recognition, social attachment, and parental behavior. Individual and species-level variation in central organization of oxytocin and vasopressin systems has been linked to individual and species variation in social learning and behavior. In humans, genetic polymorphisms in the genes encoding oxytocin and vasopressin peptides and/or their respective target receptors have been associated with individual variation in social recognition, social attachment phenotypes, parental behavior, and psychiatric phenotypes such as autism. Here we describe both conserved and variable features of central oxytocin and vasopressin systems in the context of social behavioral diversity, with a particular focus on neural networks that modulate social learning, behavior, and salience of sociosensory stimuli during species-typical social contexts. Published by Elsevier Ltd.

  3. Applying tradable permits to biodiversity conservation: A conceptual analysis of trading rules

    OpenAIRE

    Wissel, Silvia; Wätzold, Frank

    2008-01-01

    Tradable permits have already been applied in many areas of environmental policy and may be a possible response to increasing calls for flexible conservation instruments which are able to successfully conserve biodiversity while allowing for economic development. The idea behind applying tradable permits to conservation is that developers wishing to turn land to economic purposes, thereby destroying valuable habitat, may only do so if they submit a permit to the conservation agency showing th...

  4. Fostering biocultural diversity in landscapes through place-based food networks

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Kohsaka, Ryo; Bieling, Claudia

    2018-01-01

    to identify place-based food networks in Europe and Japan that reinforce linkages between biological and cultural diversity in landscapes. In our analysis of 26 European and 13 Japanese cases, we find that place-based food networks are typically located in heterogeneous landscapes, are driven by civil society...... (and less by markets), and act at a local scale. Regional identity is the most frequently addressed societal issue. Scenery, rural tourism, and nature conservation are more important motivations in Europe, and physical well-being and revitalization of local economies are more relevant in Japan...... societies), and from Europe to Japan (e.g., models that build explicit connections between food production and biodiversity conservation). We conclude with a list of recommended policy measures, e.g., the creation of a flexible legal framework that protects the interests of and reduces political constraints...

  5. ADAPTIVE GOSSIP BASED PROTOCOL FOR ENERGY EFFICIENT MOBILE ADHOC NETWORK

    Directory of Open Access Journals (Sweden)

    S. Rajeswari

    2012-03-01

    Full Text Available In Gossip Sleep Protocol, network performance is enhanced based on energy resource. But energy conservation is achieved with the reduced throughput. In this paper, it has been proposed a new Protocol for Mobile Ad hoc Network to achieve reliability with energy conservation. Based on the probability (p values, the value of sleep nodes is fixed initially. The probability value can be adaptively adjusted by Remote Activated Switch during the transmission process. The adaptiveness of gossiping probability is determined by the Packet Delivery Ratio. For performance comparison, we have taken Routing overhead, Packet Delivery Ratio, Number of dropped packets and Energy consumption with the increasing number of forwarding nodes. We used UDP based traffic models to analyze the performance of this protocol. We analyzed TCP based traffic models for average end to end delay. We have used the NS-2 simulator.

  6. Abatement costs of soil conservation in China's Loess Plateau: balancing income with conservation in an agricultural system.

    Science.gov (United States)

    Hou, Lingling; Hoag, Dana L K; Keske, Catherine M H

    2015-02-01

    This study proposes the use of marginal abatement cost curves to calculate environmental damages of agricultural systems in China's Loess Plateau. Total system costs and revenues, management characteristics and pollution attributes are imputed into a directional output distance function, which is then used to determine shadow prices and abatement cost curves for soil and nitrogen loss. Marginal abatement costs curves are an effective way to compare economic and conservation tradeoffs when field-specific data are scarce. The results show that sustainable agricultural practices can balance soil conservation and agricultural production; land need not be retired, as is current policy. Published by Elsevier Ltd.

  7. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago V. V.; Giannitsarou, Chryssi; Johnson, Charles R.

    2016-01-01

    This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00199-016-0992-1 We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and d...

  8. Creating a stakeholder-driven unified conservation blueprint for 15 southeastern states.

    Science.gov (United States)

    Hopkins, T. E.

    2017-12-01

    The dramatic changes sweeping the Southeastern United States — such as urbanization, competition for water resources, extreme weather events, sea-level rise, and climate change — pose unprecedented challenges for sustaining our natural and cultural resources. Defining the conservation landscape of the future requires a new model of working together across entities, factions, and political boundaries through a collaborative process. We will illustrate how ecosystem service valuation can be built using a stakeholder-drive process which has united the conservation community through a shared, long-term vision for the future through the Southeast Conservation Adaptation Strategy (SECAS). Through SECAS, diverse public and private partners have worked together to design and achieve a connected network of landscapes and seascapes that supports thriving fish and wildlife populations and improved quality of life for people across the southeastern U.S. and the Caribbean. The scope of SECAS is the fifteen southeastern states that comprise the Southeast Association of Fish and Wildlife Agencies (SEAFWA) plus Puerto Rico and the United States Virgin Islands. SECAS was initiated by SEAFWA and the federal Southeast Natural Resource Leaders Group with support from six Landscape Conservation Cooperatives (LCCs), the Southeast Climate Science Center, and the Southeast Aquatic Resources Partnership. In October of 2016, SECAS achieved a major milestone with the release of a first draft of a conservation blueprint for the Southeast and Caribbean. This blueprint stitches together the conservation and restoration priorities of multiple LCCs in the region into one unifying map — a living spatial plan to make the SECAS vision a reality. Whether you are an urban planner, a private landowner, a non-profit advocate, a public lands manager, or anyone else committed to sustaining our natural and cultural heritage for future generations, join the SECAS conversation at www.secassoutheast.org

  9. Predictive regulatory models in Drosophila melanogaster by integrative inference of transcriptional networks

    Science.gov (United States)

    Marbach, Daniel; Roy, Sushmita; Ay, Ferhat; Meyer, Patrick E.; Candeias, Rogerio; Kahveci, Tamer; Bristow, Christopher A.; Kellis, Manolis

    2012-01-01

    Gaining insights on gene regulation from large-scale functional data sets is a grand challenge in systems biology. In this article, we develop and apply methods for transcriptional regulatory network inference from diverse functional genomics data sets and demonstrate their value for gene function and gene expression prediction. We formulate the network inference problem in a machine-learning framework and use both supervised and unsupervised methods to predict regulatory edges by integrating transcription factor (TF) binding, evolutionarily conserved sequence motifs, gene expression, and chromatin modification data sets as input features. Applying these methods to Drosophila melanogaster, we predict ∼300,000 regulatory edges in a network of ∼600 TFs and 12,000 target genes. We validate our predictions using known regulatory interactions, gene functional annotations, tissue-specific expression, protein–protein interactions, and three-dimensional maps of chromosome conformation. We use the inferred network to identify putative functions for hundreds of previously uncharacterized genes, including many in nervous system development, which are independently confirmed based on their tissue-specific expression patterns. Last, we use the regulatory network to predict target gene expression levels as a function of TF expression, and find significantly higher predictive power for integrative networks than for motif or ChIP-based networks. Our work reveals the complementarity between physical evidence of regulatory interactions (TF binding, motif conservation) and functional evidence (coordinated expression or chromatin patterns) and demonstrates the power of data integration for network inference and studies of gene regulation at the systems level. PMID:22456606

  10. Predictive regulatory models in Drosophila melanogaster by integrative inference of transcriptional networks.

    Science.gov (United States)

    Marbach, Daniel; Roy, Sushmita; Ay, Ferhat; Meyer, Patrick E; Candeias, Rogerio; Kahveci, Tamer; Bristow, Christopher A; Kellis, Manolis

    2012-07-01

    Gaining insights on gene regulation from large-scale functional data sets is a grand challenge in systems biology. In this article, we develop and apply methods for transcriptional regulatory network inference from diverse functional genomics data sets and demonstrate their value for gene function and gene expression prediction. We formulate the network inference problem in a machine-learning framework and use both supervised and unsupervised methods to predict regulatory edges by integrating transcription factor (TF) binding, evolutionarily conserved sequence motifs, gene expression, and chromatin modification data sets as input features. Applying these methods to Drosophila melanogaster, we predict ∼300,000 regulatory edges in a network of ∼600 TFs and 12,000 target genes. We validate our predictions using known regulatory interactions, gene functional annotations, tissue-specific expression, protein-protein interactions, and three-dimensional maps of chromosome conformation. We use the inferred network to identify putative functions for hundreds of previously uncharacterized genes, including many in nervous system development, which are independently confirmed based on their tissue-specific expression patterns. Last, we use the regulatory network to predict target gene expression levels as a function of TF expression, and find significantly higher predictive power for integrative networks than for motif or ChIP-based networks. Our work reveals the complementarity between physical evidence of regulatory interactions (TF binding, motif conservation) and functional evidence (coordinated expression or chromatin patterns) and demonstrates the power of data integration for network inference and studies of gene regulation at the systems level.

  11. A combinatorial approach to detect coevolved amino acid networks in protein families of variable divergence.

    Directory of Open Access Journals (Sweden)

    Julie Baussand

    2009-09-01

    Full Text Available Communication between distant sites often defines the biological role of a protein: amino acid long-range interactions are as important in binding specificity, allosteric regulation and conformational change as residues directly contacting the substrate. The maintaining of functional and structural coupling of long-range interacting residues requires coevolution of these residues. Networks of interaction between coevolved residues can be reconstructed, and from the networks, one can possibly derive insights into functional mechanisms for the protein family. We propose a combinatorial method for mapping conserved networks of amino acid interactions in a protein which is based on the analysis of a set of aligned sequences, the associated distance tree and the combinatorics of its subtrees. The degree of coevolution of all pairs of coevolved residues is identified numerically, and networks are reconstructed with a dedicated clustering algorithm. The method drops the constraints on high sequence divergence limiting the range of applicability of the statistical approaches previously proposed. We apply the method to four protein families where we show an accurate detection of functional networks and the possibility to treat sets of protein sequences of variable divergence.

  12. Threats from urban expansion, agricultural transformation and forest loss on global conservation priority areas

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    Moilanen, Atte; Di Minin, Enrico

    2017-01-01

    Including threats in spatial conservation prioritization helps identify areas for conservation actions where biodiversity is at imminent risk of extinction. At the global level, an important limitation when identifying spatial priorities for conservation actions is the lack of information on the spatial distribution of threats. Here, we identify spatial conservation priorities under three prominent threats to biodiversity (residential and commercial development, agricultural expansion, and forest loss), which are primary drivers of habitat loss and threaten the persistence of the highest number of species in the International Union for the Conservation of Nature (IUCN) Red List, and for which spatial data is available. We first explore how global priority areas for the conservation of vertebrate (mammals, birds, and amphibians) species coded in the Red List as vulnerable to each threat differ spatially. We then identify spatial conservation priorities for all species vulnerable to all threats. Finally, we identify the potentially most threatened areas by overlapping the identified priority areas for conservation with maps for each threat. We repeat the same with four other well-known global conservation priority area schemes, namely Key Biodiversity Areas, Biodiversity Hotspots, the global Protected Area Network, and Wilderness Areas. We find that residential and commercial development directly threatens only about 4% of the global top 17% priority areas for species vulnerable under this threat. However, 50% of the high priority areas for species vulnerable to forest loss overlap with areas that have already experienced some forest loss. Agricultural expansion overlapped with ~20% of high priority areas. Biodiversity Hotspots had the greatest proportion of their total area under direct threat from all threats, while expansion of low intensity agriculture was found to pose an imminent threat to Wilderness Areas under future agricultural expansion. Our results

  13. Use of inverse spatial conservation prioritization to avoid biological diversity loss outside protected areas.

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    Kareksela, Santtu; Moilanen, Atte; Tuominen, Seppo; Kotiaho, Janne S

    2013-12-01

    Globally expanding human land use sets constantly increasing pressure for maintenance of biological diversity and functioning ecosystems. To fight the decline of biological diversity, conservation science has broken ground with methods such as the operational model of systematic conservation planning (SCP), which focuses on design and on-the-ground implementation of conservation areas. The most commonly used method in SCP is reserve selection that focuses on the spatial design of reserve networks and their expansion. We expanded these methods by introducing another form of spatial allocation of conservation effort relevant for land-use zoning at the landscape scale that avoids negative ecological effects of human land use outside protected areas. We call our method inverse spatial conservation prioritization. It can be used to identify areas suitable for economic development while simultaneously limiting total ecological and environmental effects of that development at the landscape level by identifying areas with highest economic but lowest ecological value. Our method is not based on a priori targets, and as such it is applicable to cases where the effects of land use on, for example, individual species or ecosystem types are relatively small and would not lead to violation of regional or national conservation targets. We applied our method to land-use allocation to peat mining. Our method identified a combination of profitable production areas that provides the needed area for peat production while retaining most of the landscape-level ecological value of the ecosystem. The results of this inverse spatial conservation prioritization are being used in land-use zoning in the province of Central Finland. © 2013 Society for Conservation Biology.

  14. Ethics of conservation triage

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    Kerrie A Wilson

    2016-09-01

    Full Text Available Conservation triage seems to be at a stalemate between those who accept triage based on utilitarian rationalization, and those that reject it based on a number of ethical principles. We argue that without considered attention to the ethics of conservation triage we risk further polarization in the field of conservation. We draw lessons from the medical sector, where triage is more intuitive and acceptable, and also from disaster planning, to help navigate the challenges that triage entails for conservation science, practice, and policy. We clarify the consequentialist, deontological, and virtue ethical stances that influence the level of acceptance of triage. We emphasize the ethical dimensions of conservation triage in principle and in practice, particularly in the context of stakeholder diversity, a wide range of possible objectives and actions, broader institutions, and significant uncertainties. A focus on a more diverse set of ethics, more considered choice of triage as a conservation tool, open communication of triage objectives and protocols, greater consideration of risk preferences, and regular review and adaptation of triage protocols is required for conservation triage to become more acceptable among diverse conservation practitioners, institutions, and the general public. Accepting conservation triage as fundamentally an ethical problem would foster more open dialogue and constructive debate about the role of conservation triage in a wider system of care.

  15. Synaptic potentiation facilitates memory-like attractor dynamics in cultured in vitro hippocampal networks.

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    Mark Niedringhaus

    Full Text Available Collective rhythmic dynamics from neurons is vital for cognitive functions such as memory formation but how neurons self-organize to produce such activity is not well understood. Attractor-based computational models have been successfully implemented as a theoretical framework for memory storage in networks of neurons. Additionally, activity-dependent modification of synaptic transmission is thought to be the physiological basis of learning and memory. The goal of this study is to demonstrate that using a pharmacological treatment that has been shown to increase synaptic strength within in vitro networks of hippocampal neurons follows the dynamical postulates theorized by attractor models. We use a grid of extracellular electrodes to study changes in network activity after this perturbation and show that there is a persistent increase in overall spiking and bursting activity after treatment. This increase in activity appears to recruit more "errant" spikes into bursts. Phase plots indicate a conserved activity pattern suggesting that a synaptic potentiation perturbation to the attractor leaves it unchanged. Lastly, we construct a computational model to demonstrate that these synaptic perturbations can account for the dynamical changes seen within the network.

  16. Conservation of lipid metabolic gene transcriptional regulatory networks in fish and mammals.

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    Carmona-Antoñanzas, Greta; Tocher, Douglas R; Martinez-Rubio, Laura; Leaver, Michael J

    2014-01-15

    Lipid content and composition in aquafeeds have changed rapidly as a result of the recent drive to replace ecologically limited marine ingredients, fishmeal and fish oil (FO). Terrestrial plant products are the most economic and sustainable alternative; however, plant meals and oils are devoid of physiologically important cholesterol and long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic (EPA), docosahexaenoic (DHA) and arachidonic (ARA) acids. Although replacement of dietary FO with vegetable oil (VO) has little effect on growth in Atlantic salmon (Salmo salar), several studies have shown major effects on the activity and expression of genes involved in lipid homeostasis. In vertebrates, sterols and LC-PUFA play crucial roles in lipid metabolism by direct interaction with lipid-sensing transcription factors (TFs) and consequent regulation of target genes. The primary aim of the present study was to elucidate the role of key TFs in the transcriptional regulation of lipid metabolism in fish by transfection and overexpression of TFs. The results show that the expression of genes of LC-PUFA biosynthesis (elovl and fads2) and cholesterol metabolism (abca1) are regulated by Lxr and Srebp TFs in salmon, indicating highly conserved regulatory mechanism across vertebrates. In addition, srebp1 and srebp2 mRNA respond to replacement of dietary FO with VO. Thus, Atlantic salmon adjust lipid metabolism in response to dietary lipid composition through the transcriptional regulation of gene expression. It may be possible to further increase efficient and effective use of sustainable alternatives to marine products in aquaculture by considering these important molecular interactions when formulating diets. © 2013.

  17. Water Pollution Detection Based on Hypothesis Testing in Sensor Networks

    Directory of Open Access Journals (Sweden)

    Xu Luo

    2017-01-01

    Full Text Available Water pollution detection is of great importance in water conservation. In this paper, the water pollution detection problems of the network and of the node in sensor networks are discussed. The detection problems in both cases of the distribution of the monitoring noise being normal and nonnormal are considered. The pollution detection problems are analyzed based on hypothesis testing theory firstly; then, the specific detection algorithms are given. Finally, two implementation examples are given to illustrate how the proposed detection methods are used in the water pollution detection in sensor networks and prove the effectiveness of the proposed detection methods.

  18. Priority setting for bird conservation in Mexico: the role of the Important Bird Areas program

    Science.gov (United States)

    Ma. del Coro Arizmendi; Laura Marquez Valdelamar; Humberto Berlanga

    2005-01-01

    Many species in Mexico are threatened and in need of protection. At least seventy species are considered to be globally threatened, yet conservation actions have been scarce and not coordinated. In 1996 BirdLife International’s Important Bird Areas Program was initiated in Mexico to identify a network of the most important places in Mexico for birds, with the...

  19. Fixed-time stability of dynamical systems and fixed-time synchronization of coupled discontinuous neural networks.

    Science.gov (United States)

    Hu, Cheng; Yu, Juan; Chen, Zhanheng; Jiang, Haijun; Huang, Tingwen

    2017-05-01

    In this paper, the fixed-time stability of dynamical systems and the fixed-time synchronization of coupled discontinuous neural networks are investigated under the framework of Filippov solution. Firstly, by means of reduction to absurdity, a theorem of fixed-time stability is established and a high-precision estimation of the settling-time is given. It is shown by theoretic proof that the estimation bound of the settling time given in this paper is less conservative and more accurate compared with the classical results. Besides, as an important application, the fixed-time synchronization of coupled neural networks with discontinuous activation functions is proposed. By designing a discontinuous control law and using the theory of differential inclusions, some new criteria are derived to ensure the fixed-time synchronization of the addressed coupled networks. Finally, two numerical examples are provided to show the effectiveness and validity of the theoretical results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Efficiency of a protected-area network in a Mediterranean region: a multispecies assessment with raptors.

    Science.gov (United States)

    Abellán, María D; Martínez, José E; Palazón, José A; Esteve, Miguel A; Calvo, José F

    2011-05-01

    Three different systems of designating protected areas in a Mediterranean region in southeastern Spain were studied, referring to their effectiveness and efficiency for protecting both the breeding territories and the suitable habitat of a set of ten raptor species. Taking into consideration the varying degrees of endangerment of these species, a map of multispecies conservation values was also drawn up and superimposed on the three protected-area systems studied. In order to compare the levels of protection afforded by the three systems, we considered two indices that measured their relative effectiveness and efficiency. The effectiveness estimated the proportion of territories or optimal habitat protected by the networks while efficiency implicitly considered the area of each system (percentage of breeding territories or optimal habitat protected per 1% of land protected). Overall, our results showed that the most efficient system was that formed by the set of regional parks and reserves (17 protected breeding territories per 100 km²), although, given its small total area, it was by far the least effective (only protecting the 21% of the breeding territories of all species and 17% of the area of high conservation value). The systems formed by the Special Protection Areas (designated under the EU "Birds Directive") and by the Special Conservation Areas (designated under the EU "Habitats Directive") notably increased the percentages of protected territories of all species (61%) and area of high conservation value (57%), but their efficiency was not as high as expected in most cases. The overall level of protection was high for all species except for the Lesser Kestrel (Falco naumanni), an endangered falcon that inhabits pseudo-steppe and traditional agricultural habitats, which are clearly underrepresented in the protected-area network of the study region.