Sample records for habitat life cycle

  1. Habitat-based constraints on food web structure and parasite life cycles.

    PubMed

    Rossiter, Wayne; Sukhdeo, Michael V K

    2014-04-01

    Habitat is frequently implicated as a powerful determinant of community structure and species distributions, but few studies explicitly evaluate the relationship between habitat-based patterns of species' distributions and the presence or absence of trophic interactions. The complex (multi-host) life cycles of parasites are directly affected by these factors, but almost no data exist on the role of habitat in constraining parasite-host interactions at the community level. In this study the relationship(s) between species abundances, distributions and trophic interactions (including parasitism) were evaluated in the context of habitat structure (classic geomorphic designations of pools, riffles and runs) in a riverine community (Raritan River, Hunterdon County, NJ, USA). We report 121 taxa collected over a 2-year period, and compare the observed food web patterns to null model expectations. The results show that top predators are constrained to particular habitat types, and that species' distributions are biased towards pool habitats. However, our null model (which incorporates cascade model assumptions) accurately predicts the observed patterns of trophic interactions. Thus, habitat strongly dictates species distributions, and patterns of trophic interactions arise as a consequence of these distributions. Additionally, we find that hosts utilized in parasite life cycles are more overlapping in their distributions, and this pattern is more pronounced among those involved in trophic transmission. We conclude that habitat structure may be a strong predictor of parasite transmission routes, particularly within communities that occupy heterogeneous habitats.

  2. Potential Habitats for Exotic Life Within the Life Supporting Zone

    NASA Astrophysics Data System (ADS)

    Leitner, Johannes J.; Firneis, Maria G.; Hitzenberger, Regina

    2010-05-01

    System and beyond have been compiled. Dynamical investigations (related to the interior of superearths), but also heat transport regimes and potential cycles with exotic solvents as well as tidal heating processes and their influence on the thermal regime of the planets will help to define the regions of potential exotic life more precisely. Atmospheric and subsurface cycles which can take place in such habitats as well as cloud and droplet formation with and without cloud nuclei cores will further extend our knowledge on mechanisms relevant for the stability of these systems. Finally the question of suitable biomarkers, which can enable the observation of exotic habitats and their potential life forms will be considered in the research platform. In this context a special topic is also the bandwidth of photosynthesis: how is the influence of different atmospheric gases and what are the environment conditions for the chemical reactions of photosynthesis? First preliminary results for the life supporting zones of selected planetary systems will be presented. References: [1] NRC (National Research Council)(2007) The Limits of Organic Life in Planetary Systems, National Academies Press, Washington, DC 20001, ISBN 978-0-309-10484-5. [2] Kasting, J.F., Whitmore D.P. and Reynolds R.T. (1993) Icarus, 101, 109-128.

  3. Developing closed life support systems for large space habitats

    NASA Technical Reports Server (NTRS)

    Phillips, J. M.; Harlan, A. D.; Krumhar, K. C.

    1978-01-01

    In anticipation of possible large-scale, long-duration space missions which may be conducted in the future, NASA has begun to investigate the research and technology development requirements to create life support systems for large space habitats. An analysis suggests the feasibility of a regeneration of food in missions which exceed four years duration. Regeneration of food in space may be justified for missions of shorter duration when large crews must be supported at remote sites such as lunar bases and space manufacturing facilities. It is thought that biological components consisting principally of traditional crop and livestock species will prove to be the most acceptable means of closing the food cycle. A description is presented of the preliminary results of a study of potential biological components for large space habitats. Attention is given to controlled ecosystems, Russian life support system research, controlled-environment agriculture, and the social aspects of the life-support system.

  4. The phylogeny and life cycle of two species of Profilicollis (Acanthocephala: Polymorphidae) in marine hosts off the Pacific coast of Chile.

    PubMed

    Rodríguez, S M; D'Elía, G; Valdivia, N

    2017-09-01

    Resolving complex life cycles of parasites is a major goal of parasitological research. The aim of this study was to analyse the life cycle of two species of the genus Profilicollis, the taxonomy of which is still unstable and life cycles unclear. We extracted individuals of Profilicollis from two species of crustaceans (intermediate hosts) and four species of seagulls (definitive hosts) from sandy-shore and estuarine habitats along the south-east Pacific coast of Chile. Mitochondrial DNA analyses showed that two species of Profilicollis infected intermediate hosts from segregated habitats: while P. altmani larvae infected exclusively molecrabs of the genus Emerita from fully marine habitats, P. antarcticus larvae infected the crab Hemigrapsus crenulatus from estuarine habitats. Moreover, P. altmani completed its life cycle in four seagulls, Chroicocephalus maculipennis, Leucopheus pipixcan, Larus modestus and L. dominicanus, while P. antarcticus, on the other hand, completed its life cycle in the kelp gull L. dominicanus. Accordingly, our results show that two congeneric parasites use different and spatially segregated species as intermediate hosts, and both are capable of infecting one species of definitive hosts. As such, our analyses allow us to shed light on a complex interaction network.

  5. Physical habitat predictors of Manayunkia speciosa distribution in the Klamath River and implications for management of Ceratomyxa shasta, a parasite with a complex life cycle

    NASA Astrophysics Data System (ADS)

    Jordan, M. S.; Alexander, J. D.; Grant, G. E.; Bartholomew, J. L.

    2011-12-01

    Management strategies for parasites with complex life cycles may target not the parasite itself, but one of the alternate hosts. One approach is to decrease habitat for the alternate host, and in river systems flow manipulations may be employed. Two-dimensional hydraulic models can be powerful tools for predicting the relationship between flow alterations and changes in physical habit, however they require a rigorous definition of physical habitat for the organism of interest. We present habitat characterization data for the case of the alternate host of a salmonid parasite and introduce how it will be used in conjunction with a 2-dimensional hydraulic model. Ceratomyxa shasta is a myxozoan parasite of salmonids that requires a freshwater polychaete Manayunkia speciosa to complete its life cycle. Manayunkia speciosa is a small (3mm) benthic filter-feeding worm that attaches itself perpendicularly to substrate through construction of a flexible tube. In the Klamath River, CA/OR, C. shasta causes significant juvenile salmon mortality, imposing social and economic losses on commercial, sport and tribal fisheries. An interest in manipulating habitat for the polychaete host to decrease the abundance of C. shasta has therefore developed. Unfortunately, there are limited data on the habitat requirements of M. speciosa or the influence of streamflow regime and hydraulics on population dynamics and infection prevalence. This work aims to address these data needs by identifying physical habitat variables that influence the distribution of M. speciosa and determining the relationship between those variables, M. speciosa population density, and C. shasta infection prevalence. Biological samples were collected from nine sites representing three river features (runs, pools, and eddies) within the Klamath River during the summer and fall of 2010 and 2011. Environmental data including depth, velocity, and substrate, were collected at each polychaete sampling location. We tested

  6. From Rivers to Oceans and Back: Linking Models to Encompass the Full Salmon Life Cycle

    NASA Astrophysics Data System (ADS)

    Danner, E.; Hendrix, N.; Martin, B.; Lindley, S. T.

    2016-02-01

    Pacific salmon are a promising study subject for investigating the linkages between freshwater and coastal ocean ecosystems. Salmon use a wide range of habitats throughout their life cycle as they move with water from mountain streams, mainstem rivers, estuaries, bays, and coastal oceans, with adult fish swimming back through the same migration route they took as juveniles. Conditions in one habitat can have growth and survival consequences that manifest in the following habitat, so is key that full life cycle models are used to further our understanding salmon population dynamics. Given the wide range of habitats and potential stressors, this approach requires the coordination of a multidisciplinary suite of physical and biological models, including climate, hydrologic, hydraulic, food web, circulation, bioenergetic, and ecosystem models. Here we present current approaches to linking physical and biological models that capture the foundational drivers for salmon in complex and dynamic systems.

  7. Spatial variation in density and size structure indicate habitat selection throughout life stages of two Southwestern Atlantic snappers.

    PubMed

    Aschenbrenner, Alexandre; Hackradt, Carlos Werner; Ferreira, Beatrice Padovani

    2016-02-01

    The early life history of Lutjanus alexandrei and Lutjanus jocu in Southwestern Atlantic is still largely unknown. Habitat use of different life stages (i.e. size categories and densities) of the Brazilian snapper (L. alexandrei) and dog snapper (L. jocu) was examined in a tropical portion of NE coast of Brazil. Visual surveys were conducted in different shallow habitats (mangroves and reefs). Both snapper species showed higher densities in early life stages in mangrove habitat, with a clear increase in fish size from mangrove to adjacent reefs. Post-settler individuals were exclusively found in mangroves for both species. Juveniles of L. alexandrei were also registered only in mangroves, while sub-adult individuals were associated with both mangrove and reef habitats. Mature individuals of L. alexandrei were only observed in reef habitats. Juvenile and sub-adult individuals of the dog snapper were both associated with mangrove and reef habitats, with high densities registered in mangroves. Mature individuals of L. jocu were not registered in the study area. This pattern suggests preference for mangrove habitat in early life stages for both species. Ontogenetic movement between habitats was also recorded. This pattern denotes habitat selection across different life cycle of both species. Such information highlights the importance of directing management and conservation efforts to these habitats to secure the continuity of contribution to adult populations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. How Metamorphosis Is Different in Plethodontids: Larval Life History Perspectives on Life-Cycle Evolution

    PubMed Central

    Beachy, Christopher K.; Ryan, Travis J.; Bonett, Ronald M.

    2017-01-01

    Plethodontid salamanders exhibit biphasic, larval form paedomorphic, and direct developing life cycles. This diversity of developmental strategies exceeds that of any other family of terrestrial vertebrate. Here we compare patterns of larval development among the three divergent lineages of biphasic plethodontids and other salamanders. We discuss how patterns of life-cycle evolution and larval ecology might have produced a wide array of larval life histories. Compared with many other salamanders, most larval plethodontids have relatively slow growth rates and sometimes exceptionally long larval periods (up to 60 mo). Recent phylogenetic analyses of life-cycle evolution indicate that ancestral plethodontids were likely direct developers. If true, then biphasic and paedomorphic lineages might have been independently derived through different developmental mechanisms. Furthermore, biphasic plethodontids largely colonized stream habitats, which tend to have lower productivity than seasonally ephemeral ponds. Consistent with this, plethodontid larvae grow very slowly, and metamorphic timing does not appear to be strongly affected by growth history. On the basis of this, we speculate that feeding schedules and stress hormones might play a comparatively reduced role in governing the timing of metamorphosis of stream-dwelling salamanders, particularly plethodontids. PMID:29269959

  9. Life Cycle of Chetoneura shennonggongensis (Diptera: Keroplatidae, Keroplatinae) From Jiangxi Province, China

    USDA-ARS?s Scientific Manuscript database

    The biology and life cycle of the predatory fly, Chetoneura shennonggongensis, is documented from field and laboratory studies in China. This species is a member of the family Keroplatidae, all members of which prey on small invertebrates. Keroplatids prefer damp, low-light habitats, including cav...

  10. Habitat and distribution of post-recruit life stages of the squid Loligo forbesii

    NASA Astrophysics Data System (ADS)

    Smith, Jennifer M.; Macleod, Colin D.; Valavanis, Vasilis; Hastie, Lee; Valinassab, Tooraj; Bailey, Nick; Santos, M. Begoña; Pierce, Graham J.

    2013-10-01

    This study models habitat preferences of the squid Loligo forbesii through its post-recruitment life cycle in waters around Scotland (UK). Trawl survey and market sample data from 1985 to 2004 are used to model seasonal habitats of immature, maturing and mature squid (maturity being inferred from size and season). Squid presence-absence and catch rate in areas of presence were analysed using generalised additive models, relating spatiotemporal patterns of distribution and abundance to ecogeographic variables. For all maturity classes, higher abundance in winter and spring (i.e., quarters 1 and 2) was associated with deeper water while higher abundance in summer and autumn (quarters 3 and 4) was associated with shallower water, consistent with seasonal onshore-offshore migrations but suggesting that most spawning may take place in deeper waters. The preferred SST range was generally 8-8.75 °C while preferred salinity values were below 35‰ in winter and summer and above 35‰ in spring and autumn. Squid were positively associated with gravel substrate and negatively associated with mud. Seasonal changes in habitat use were more clearly evident than changes related to inferred maturity, although the two effects cannot be fully separated due to the annual life cycle. Habitat selection for this species can be satisfactorily modelled on a seasonal basis; predictions based on such models could be useful for fishers to target the species more effectively, and could assist managers wishing to protect spawning grounds. The extent to which this approach may be useful for other cephalopods is discussed.

  11. Mangrove habitat partitioning by Ucides cordatus (Ucididae): effects of the degree of tidal flooding and tree-species composition during its life cycle

    NASA Astrophysics Data System (ADS)

    Wunderlich, A. C.; Pinheiro, M. A. A.

    2013-06-01

    Environmental factors strongly affect mangrove crabs, and some factors modulate population structure and habitat partitioning during the crabs' life cycle. However, the effect of these environmental factors on habitat selection by mangrove crabs is still unknown. We evaluated habitat selection by the mangrove crab Ucides cordatus in mangrove forests with different degrees of predominance of Rhizophora mangle, Laguncularia racemosa or Avicennia schaueriana, two tidal flooding levels (less- and more-flooded), and two biological periods (breeding and non-breeding seasons). Sampling was conducted in four mangrove forests with different influences of these biotic and abiotic parameters. We used the data for sex ratio to explain environmental partitioning by this species. Females predominated in R. mangle mangroves, independently of the biological period (breeding or non-breeding seasons), and males predominated only in the less-flooded L. racemosa mangroves. The flooding level affected the sex ratio of U. cordatus, with a predominance of males in less-flooded mangroves, independently of the biological period; and a gender balance in the more-flooded mangroves only during the breeding season. Outside the breeding season, the largest specimens were recorded in the R. mangle mangroves, but in the breeding season, the largest crabs were recorded in the L. racemosa mangroves with a higher level of flooding. These results suggest that tree-species composition and tidal flooding level can have a significant effect on the habitat partitioning of sexes and sizes of the mangrove crab U. cordatus both during and outside the breeding season.

  12. Effects of tide cycles on habitat selection and habitat partitioning by migrating shorebirds

    USGS Publications Warehouse

    Burger, J.; Howe, M.A.; Hahn, D.C.; Chase, J.

    1977-01-01

    We studied assemblages of feeding shorebirds in three intertidal habitats on the coast of New Jersey during August to document how species segregate spatially both among and within habitats and to determine the effects of tidal cycles on these patterns. The habitats were a sandy beach facing the ocean proper (outer beach), a sandy beach on the mainland side of a barrier island (inner beach), and a small mudflat adjacent to a Spartina alterniflora salt marsh. We were able to identify several microhabitats on the outer beach and mudflat. Most species fed in more than one habitat, but only two, Charadrius semipalmatus and Calidris canutus, used all three habitats regularly. Within habitats, most species exhibited strong preferences for the wettest areas, but we found differences among species in degrees of preference. The least amount of partitioning occurred on the inner beach, where birds crowded into a small zone near the water's edge and had frequent agonistic encounters suggesting intense competition. Shorebird feeding activity was partly a function of tide time: each habitat had a characteristic temporal pattern of use by shorebirds related to tide time rather than diel time; within habitats, we found species-characteristic feeding activity rhythms that were also a function of tide time. Feeding by most species peaked during the first 2 hours after low tide on the outer beach and mudflat. The results are discussed in terms of feeding strategies and interspecific competition.

  13. High-resolution assessment of land use impacts on biodiversity in life cycle assessment using species habitat suitability models.

    PubMed

    de Baan, Laura; Curran, Michael; Rondinini, Carlo; Visconti, Piero; Hellweg, Stefanie; Koellner, Thomas

    2015-02-17

    Agricultural land use is a main driver of global biodiversity loss. The assessment of land use impacts in decision-support tools such as life cycle assessment (LCA) requires spatially explicit models, but existing approaches are either not spatially differentiated or modeled at very coarse scales (e.g., biomes or ecoregions). In this paper, we develop a high-resolution (900 m) assessment method for land use impacts on biodiversity based on habitat suitability models (HSM) of mammal species. This method considers potential land use effects on individual species, and impacts are weighted by the species' conservation status and global rarity. We illustrate the method using a case study of crop production in East Africa, but the underlying HSMs developed by the Global Mammals Assessment are available globally. We calculate impacts of three major export crops and compare the results to two previously developed methods (focusing on local and regional impacts, respectively) to assess the relevance of the methodological innovations proposed in this paper. The results highlight hotspots of product-related biodiversity impacts that help characterize the links among agricultural production, consumption, and biodiversity loss.

  14. Analysing how plants in coastal wetlands respond to varying tidal regimes throughout their life cycles.

    PubMed

    Xie, Tian; Cui, Baoshan; Li, Shanze

    2017-10-15

    Important to conserve plant species in coastal wetlands throughout their life cycle. All life stages in these habitats are exposed to varying tidal cycles. It is necessary to investigate all life stages as to how they respond to varying tidal regimes. We examine three wetlands containing populations of an endangered halophyte species, each subjected to different tidal regimes: (1). wetlands completely closed to tidal cycles; (2). wetlands directly exposed to tidal cycles (3). wetlands exposed to a partially closed tidal regime. Our results showed that the most threatened stage varied between wetlands subjected to these varying tidal regimes. We hypothesis that populations of this species have adapted to these different tidal regimes. Such information is useful in developing management options for coastal wetlands and modifying future barriers restricting tidal flushing. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Variations in the Life Cycle of Anemone patens L. (Ranunculaceae) in Wild Populations of Canada

    PubMed Central

    Kricsfalusy, Vladimir

    2016-01-01

    Based on a study of a perennial herb Anemone patens L. (Ranunculaceae) in a variety of natural habitats in Saskatchewan, Canada, eight life stages (seed, seedling, juvenile, immature, vegetative, generative, subsenile, and senile) are distinguished and characterized in detail. The species ontogenetic growth patterns are investigated. A. patens has a long life cycle that may last for several decades which leads to the formation of compact clumps. The distribution and age of clumps vary substantially in different environments with different levels of disturbance. The plant ontogeny includes the regular cycle with reproduction occurring through seeds. There is an optional subsenile vegetative disintegration at the end of the life span. The following variations in the life cycle of A. patens are identified: with slower development in young age, with an accelerated development, with omission of the generative stage, with retrogression to previous life stages in mature age, and with vegetative dormancy. The range of variations in the life cycle of A. patens may play an important role in maintaining population stability in different environmental conditions and management regimes. PMID:27376340

  16. Multi level ecological fitting: indirect life cycles are not a barrier to host switching and invasion.

    PubMed

    Malcicka, Miriama; Agosta, Salvatore J; Harvey, Jeffrey A

    2015-09-01

    Many invasive species are able to escape from coevolved enemies and thus enjoy a competitive advantage over native species. However, during the invasion phase, non-native species must overcome many ecological and/or physiological hurdles before they become established and spread in their new habitats. This may explain why most introduced species either fail to establish or remain as rare interstitials in their new ranges. Studies focusing on invasive species have been based on plants or animals where establishment requires the possession of preadapted traits from their native ranges that enables them to establish and spread in their new habitats. The possession of preadapted traits that facilitate the exploitation of novel resources or to colonize novel habitats is known as 'ecological fitting'. Some species have evolved traits and life histories that reflect highly intimate associations with very specific types of habitats or niches. For these species, their phenological windows are narrow, and thus the ability to colonize non-native habitats requires that a number of conditions need to be met in accordance with their more specialized life histories. Some of the strongest examples of more complex ecological fitting involve invasive parasites that require different animal hosts to complete their life cycles. For instance, the giant liver fluke, Fascioloides magna, is a major parasite of several species of ungulates in North America. The species exhibits a life cycle whereby newly hatched larvae must find suitable intermediate hosts (freshwater snails) and mature larvae, definitive hosts (ungulates). Intermediate and definitive host ranges of F. magna in its native range are low in number, yet this parasite has been successfully introduced into Europe where it has become a parasite of native European snails and deer. We discuss how the ability of these parasites to overcome multiple ecophysiological barriers represents an excellent example of 'multiple

  17. Transportation life cycle assessment (LCA) synthesis : life cycle assessment learning module series.

    DOT National Transportation Integrated Search

    2015-03-12

    The Life Cycle Assessment Learning Module Series is a set of narrated, self-advancing slideshows on : various topics related to environmental life cycle assessment (LCA). This research project produced the first 27 of such modules, which : are freely...

  18. Architecture and life support systems for a rotating space habitat

    NASA Astrophysics Data System (ADS)

    Misra, Gaurav

    Life Support Systems are critical to sustain human habitation of space over long time periods. As orbiting space habitats become operational in the future, support systems such as atmo-sphere, food, water etc. will play a very pivotal role in sustaining life. To design a long-duration space habitat, it's important to consider the full gamut of human experience of the environment. Long-term viability depends on much more than just the structural or life support efficiency. A space habitat isn't just a machine; it's a life experience. To be viable, it needs to keep the inhabitants satisfied with their condition. This paper provides conceptual research on several key factors that influence the growth and sustainability of humans in a space habitat. Apart from the main life support system parameters, the architecture (both interior and exterior) of the habitat will play a crucial role in influencing the liveability in the space habitat. In order to ensure the best possible liveability for the inhabitants, a truncated (half cut) torus is proposed as the shape of the habitat. This structure rotating at an optimum rpm will en-sure 1g pseudo gravity to the inhabitants. The truncated torus design has several advantages over other proposed shapes such as a cylinder or a sphere. The design provides minimal grav-ity variation (delta g) in the living area, since its flat outer pole ensures a constant gravity. The design is superior in economy of structural and atmospheric mass. Interior architecture of the habitat addresses the total built environment, drawing from diverse disciplines includ-ing physiology, psychology, and sociology. Furthermore, factors such as line of sight, natural sunlight and overhead clearance have been discussed in the interior architecture. Substantial radiation shielding is also required in order to prevent harmful cosmic radiations and solar flares from causing damage to inhabitants. Regolith shielding of 10 tons per meter square is proposed for the

  19. Habitat use and life history of the vernal crayfish, Procambarus viaeviridis (Faxon, 1914), a secondary burrowing crayfish in Mississippi, USA

    Treesearch

    Zanethia C. Barnett; Susan B. Adams; Rebecca L.   Rosamond

    2017-01-01

    The Lower Mississippi Alluvial Valley (LMAV) is a species-rich region in North America, but its crayfish community has not been extensively sampled. We investigated the annual life cycle, habitat use, and some morphological characteristics of the vernal crayfish, Procambarus viaeviridis (Faxon, 1914), in the Dahomey National Wildlife Refuge,...

  20. Reducing Life-Cycle Costs.

    ERIC Educational Resources Information Center

    Roodvoets, David L.

    2003-01-01

    Presents factors to consider when determining roofing life-cycle costs, explaining that costs do not tell the whole story; discussing components that should go into the decision (cost, maintenance, energy use, and environmental costs); and concluding that important elements in reducing life-cycle costs include energy savings through increased…

  1. Altair Lander Life Support: Design Analysis Cycles 1, 2, and 3

    NASA Technical Reports Server (NTRS)

    Anderson, Molly; Rotter, Hank; Stambaugh, Imelda; Curley, Su

    2009-01-01

    NASA is working to develop a new lunar lander to support lunar exploration. The development process that the Altair project is using for this vehicle is unlike most others. In Lander Design Analysis Cycle 1 (LDAC-1), a single-string, minimum functionality design concept was developed, including life support systems for different vehicle configuration concepts, first for a combination of an ascent vehicle and a habitat with integral airlocks, and then for a combined ascent vehicle-habitat with a detachable airlock. In LDAC-2, the Altair team took the ascent vehicle-habitat with detachable airlock and analyzed the design for the components that were the largest contributors to the risk of loss of crew (LOC). For life support, the largest drivers were related to oxygen supply and carbon dioxide control. Integrated abort options were developed at the vehicle level. Many life support failures were not considered to result in LOC because they had a long enough time to effect that abort was considered a feasible option to safely end the mission before the situation became life threatening. These failures were then classified as loss of mission (LOM) failures. Many options to reduce LOC risk were considered, and mass efficient solutions to the LOC problems were added to the vehicle design at the end of LDAC-2. In LDAC-3, the new design was analyzed for large contributors to the risk of LOM. To avoid ending the mission early or being unable to accomplish goals like performing all planned extravehicular activities (EVAs), various options were assessed for their combination of risk reduction and mass cost. This paper outlines the major assumptions, design features, and decisions related to the development of the life support system for the Altair project through LDAC-3.

  2. Insect seasonality: circle map analysis of temperature-driven life cycles.

    PubMed

    Powell, James A; Logan, Jesse A

    2005-05-01

    Maintaining an adaptive seasonality, with life cycle events occurring at appropriate times of year and in synchrony with cohorts and ephemeral resources, is a basic ecological requisite for many cold-blooded organisms. There are many mechanisms for synchronizing developmental milestones, such as egg laying (oviposition), egg hatching, cocoon opening, and the emergence of adults. These are often irreversible, specific to particular life stages, and include diapause, an altered physiological state which can be reversed by some synchronizing environmental cue (e.g. photoperiod). However, many successful organisms display none of these mechanisms for maintaining adaptive seasonality. In this paper, we briefly review the mathematical relationship between environmental temperatures and developmental timing and discuss the consequences of viewing these models as circle maps from the cycle of yearly oviposition dates and temperatures to oviposition dates for subsequent generations. Of particular interest biologically are life cycles which are timed to complete in exactly 1 year, or univoltine cycles. Univoltinism, associated with reproductive success for many temperate species, is related to stable fixed points of the developmental circle map. Univoltine fixed points are stable and robust in broad temperature bands, but lose stability suddenly to maladaptive cycles at the edges of these bands. Adaptive seasonality may therefore break down with little warning with constantly increasing or decreasing temperature change, as in scenarios for global warming. These ideas are illustrated and explored in the context of Mountain Pine Beetle (Dendroctonus ponderosae Hopkins) occurring in the marginal thermal habitat of central Idaho's Rocky Mountains. Applications of these techniques have not been widely explored by the applied math community, but are likely to provide great insight into the response of biological systems to climate change.

  3. Does It Have a Life Cycle?

    ERIC Educational Resources Information Center

    Keeley, Page

    2010-01-01

    If life continues from generation to generation, then all plants and animals must go through a life cycle, even though it may be different from organism to organism. Is this what students have "learned," or do they have their own private conceptions about life cycles? The formative assessment probe "Does It Have a Life Cycle?" reveals some…

  4. Linking habitat structure to life history strategy: Insights from a Mediterranean killifish

    NASA Astrophysics Data System (ADS)

    Cavraro, Francesco; Daouti, Irini; Leonardos, Ioannis; Torricelli, Patrizia; Malavasi, Stefano

    2014-01-01

    Modern theories of life history evolution deal with finding links between environmental factors, demographic structure of animal populations and the optimal life history strategy. Small-sized teleost fish, occurring in fragmented populations under contrasting environments, have been widely used as study models to investigate these issues. In the present study, the Mediterranean killifish Aphanius fasciatus was used to investigate the relationships between some habitat features and life history strategy. We selected four sites in the Venice lagoon inhabited by this species, exhibiting different combinations of two factors: overall adult mortality, related to intertidal water coverage and a consequent higher level of predator exposure, and the level of sediment organic matter, as indicator of habitat trophic richness. Results showed that these were the two most important factors influencing demography and life history traits in the four sites. Fish from salt marshes with high predator pressure were smaller and produced a higher number of eggs, whereas bigger fish and a lower reproductive investment were found in the two closed, not tidally influenced habitats. Habitat richness was positively related with population density, but negatively related with growth rate. In particular the synergy between high resources and low predation level was found to be important in shaping peculiar life history traits. Results were discussed in the light of the interactions between selective demographic forces acting differentially on age/size classes, such as predation, and habitat trophic richness that may represent an important energetic constraint on life history traits. The importance to link habitat productivity and morphology to demographic factors for a better understanding of the evolution of life history strategy under contrasting environments was finally suggested.

  5. Geographic body size variation in the periodical cicadas Magicicada: implications for life cycle divergence and local adaptation.

    PubMed

    Koyama, T; Ito, H; Kakishima, S; Yoshimura, J; Cooley, J R; Simon, C; Sota, T

    2015-06-01

    Seven species in three species groups (Decim, Cassini and Decula) of periodical cicadas (Magicicada) occupy a wide latitudinal range in the eastern United States. To clarify how adult body size, a key trait affecting fitness, varies geographically with climate conditions and life cycle, we analysed the relationships of population mean head width to geographic variables (latitude, longitude, altitude), habitat annual mean temperature (AMT), life cycle and species differences. Within species, body size was larger in females than males and decreased with increasing latitude (and decreasing habitat AMT), following the converse Bergmann's rule. For the pair of recently diverged 13- and 17-year species in each group, 13-year cicadas were equal in size or slightly smaller on average than their 17-year counterparts despite their shorter developmental time. This fact suggests that, under the same climatic conditions, 17-year cicadas have lowered growth rates compared to their 13-years counterparts, allowing 13-year cicadas with faster growth rates to achieve body sizes equivalent to those of their 17-year counterparts at the same locations. However, in the Decim group, which includes two 13-year species, the more southerly, anciently diverged 13-year species (Magicicada tredecim) was characterized by a larger body size than the other, more northerly 13- and 17-year species, suggesting that local adaptation in warmer habitats may ultimately lead to evolution of larger body sizes. Our results demonstrate how geographic clines in body size may be maintained in sister species possessing different life cycles. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  6. 10 CFR 436.19 - Life cycle costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Life cycle costs. 436.19 Section 436.19 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.19 Life cycle costs. Life cycle costs are the sum of the...

  7. 10 CFR 436.19 - Life cycle costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life cycle costs. 436.19 Section 436.19 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.19 Life cycle costs. Life cycle costs are the sum of the...

  8. Life Cycle Costing.

    ERIC Educational Resources Information Center

    McCraley, Thomas L.

    1985-01-01

    Life cycle costing establishes a realistic comparison of the cost of owning and operating products. The formula of initial cost plus maintenance plus operation divided by useful life identifies the best price over the lifetime of the product purchased. (MLF)

  9. Amphibian terrestrial habitat selection and movement patterns vary with annual life-history period

    USGS Publications Warehouse

    Groff, Luke A.; Calhoun, Aram J.K.; Loftin, Cynthia S.

    2017-01-01

    Identification of essential habitat is a fundamental component of amphibian conservation; however, species with complex life histories frequently move among habitats. To better understand dynamic habitat use, we evaluated Wood Frog (Lithobates sylvaticus (LeConte, 1825)) habitat selection and movement patterns during the spring migration and foraging periods and described the spatiotemporal variability of habitats used during all annual life-history periods. We radio-tracked 71 frogs in Maine during 2011–2013 and evaluated spring migration, foraging activity center (FAC), and within-FAC habitat selection. Telemetered frogs spent the greatest percentage of each field season in hibernacula (≥54.4%), followed by FACs (≥25.5%), migration habitat (≥16.9%), and breeding sites (≥4.5%). FACs ranged 49 – 1 335 m2 (568.0 ± 493.4 m2) and annual home ranges spanned 1 413 – 32 165 m2 (11 780.6 ± 12 506.1 m2). During spring migration, Wood Frogs exhibited different movement patterns (e.g., turn angles), selected different habitat features, and selected habitat features less consistently than while occupying FACs, indicating that the migration and foraging periods are ecologically distinct. Habitat-use studies that do not discriminate among annual life-history periods may obscure true ecological relationships and fail to identify essential habitat necessary for sustaining amphibian populations.

  10. Habitat split and the global decline of amphibians.

    PubMed

    Becker, Carlos Guilherme; Fonseca, Carlos Roberto; Haddad, Célio Fernando Baptista; Batista, Rômulo Fernandes; Prado, Paulo Inácio

    2007-12-14

    The worldwide decline in amphibians has been attributed to several causes, especially habitat loss and disease. We identified a further factor, namely "habitat split"-defined as human-induced disconnection between habitats used by different life history stages of a species-which forces forest-associated amphibians with aquatic larvae to make risky breeding migrations between suitable aquatic and terrestrial habitats. In the Brazilian Atlantic Forest, we found that habitat split negatively affects the richness of species with aquatic larvae but not the richness of species with terrestrial development (the latter can complete their life cycle inside forest remnants). This mechanism helps to explain why species with aquatic larvae have the highest incidence of population decline. These findings reinforce the need for the conservation and restoration of riparian vegetation.

  11. The Model Life-cycle: Training Module

    EPA Pesticide Factsheets

    Model Life-Cycle includes identification of problems & the subsequent development, evaluation, & application of the model. Objectives: define ‘model life-cycle’, explore stages of model life-cycle, & strategies for development, evaluation, & applications.

  12. 10 CFR 436.19 - Life cycle costs.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Life cycle costs. 436.19 Section 436.19 Energy DEPARTMENT... Procedures for Life Cycle Cost Analyses § 436.19 Life cycle costs. Life cycle costs are the sum of the... (d) Energy and/or water costs. [55 FR 48220, Nov. 20, 1990, as amended at 61 FR 32651, June 25, 1996] ...

  13. 10 CFR 436.19 - Life cycle costs.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Life cycle costs. 436.19 Section 436.19 Energy DEPARTMENT... Procedures for Life Cycle Cost Analyses § 436.19 Life cycle costs. Life cycle costs are the sum of the... (d) Energy and/or water costs. [55 FR 48220, Nov. 20, 1990, as amended at 61 FR 32651, June 25, 1996] ...

  14. 10 CFR 436.19 - Life cycle costs.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Life cycle costs. 436.19 Section 436.19 Energy DEPARTMENT... Procedures for Life Cycle Cost Analyses § 436.19 Life cycle costs. Life cycle costs are the sum of the... (d) Energy and/or water costs. [55 FR 48220, Nov. 20, 1990, as amended at 61 FR 32651, June 25, 1996] ...

  15. Life-cycle economics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lunde, P.J.

    1982-09-01

    In a continuation of previous economic analyses, life-cycle economics of solar projects are discussed using the concept of net present value (NPV) or net worth. The discount rate is defined and illustrated and a life-cycle analysis is worked out based on no down payment and a 25-year loan. The advantages of rising NPV are discussed and illustrated using an energy conserving $100 storm window as an example. Real payback period is discussed and it is concluded that NPV is the only valid method for the evaluation of an investment. Return on investment is cited as a satisfactory alternative method. (MJJ)

  16. Habitat suitability index models: Black crappie

    USGS Publications Warehouse

    Edwards, Elizabeth A.; Krieger, Douglas A.; Bacteller, Mary; Maughan, O. Eugene

    1982-01-01

    Characteristics and habitat requirements of the black crappie (Pomoxis nigromaculatus) are described in a review of Habitat Suitability Index models. This is one in a series of publications to provide information on the habitat requirements of selected fish and wildlife species. Numerous literature sources have been consulted in an effort to consolidate scientific data on species-habitat relationships. These data have subsequently been synthesized into explicit Habitat Suitability Index (HSI) models. The models are based on suitability indices indicating habitat preferences. Indices have been formulated for variables found to affect the life cycle and survival of each species. Habitat Suitability Index (HSI) models are designed to provide information for use in impact assessment and habitat management activities. The HSI technique is a corollary to the U.S. Fish and Wildlife Service's Habitat Evaluation Procedures.

  17. Life Cycle Assessment for Biofuels

    EPA Science Inventory

    A presentation based on life cycle assessment (LCA) for biofuels is given. The presentation focuses on energy and biofuels, interesting environmental aspects of biofuels, and how to do a life cycle assessment with some examples related to biofuel systems. The stages of a (biofuel...

  18. 10 CFR 435.8 - Life-cycle costing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Life-cycle costing. 435.8 Section 435.8 Energy DEPARTMENT...-cycle costing. Each Federal agency shall determine life-cycle cost-effectiveness by using the procedures..., including lower life-cycle costs, positive net savings, savings-to-investment ratio that is estimated to be...

  19. 10 CFR 435.8 - Life-cycle costing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Life-cycle costing. 435.8 Section 435.8 Energy DEPARTMENT...-cycle costing. Each Federal agency shall determine life-cycle cost-effectiveness by using the procedures..., including lower life-cycle costs, positive net savings, savings-to-investment ratio that is estimated to be...

  20. 10 CFR 435.8 - Life-cycle costing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Life-cycle costing. 435.8 Section 435.8 Energy DEPARTMENT...-cycle costing. Each Federal agency shall determine life-cycle cost-effectiveness by using the procedures..., including lower life-cycle costs, positive net savings, savings-to-investment ratio that is estimated to be...

  1. 10 CFR 433.8 - Life-cycle costing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Life-cycle costing. 433.8 Section 433.8 Energy DEPARTMENT... HIGH-RISE RESIDENTIAL BUILDINGS § 433.8 Life-cycle costing. Each Federal agency shall determine life... choose to use any of four methods, including lower life-cycle costs, positive net savings, savings-to...

  2. 10 CFR 433.8 - Life-cycle costing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Life-cycle costing. 433.8 Section 433.8 Energy DEPARTMENT... HIGH-RISE RESIDENTIAL BUILDINGS § 433.8 Life-cycle costing. Each Federal agency shall determine life... choose to use any of four methods, including lower life-cycle costs, positive net savings, savings-to...

  3. 10 CFR 433.8 - Life-cycle costing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Life-cycle costing. 433.8 Section 433.8 Energy DEPARTMENT... HIGH-RISE RESIDENTIAL BUILDINGS § 433.8 Life-cycle costing. Each Federal agency shall determine life... choose to use any of four methods, including lower life-cycle costs, positive net savings, savings-to...

  4. Invasion of novel habitats uncouples haplo-diplontic life cycles.

    PubMed

    Krueger-Hadfield, Stacy A; Kollars, Nicole M; Byers, James E; Greig, Thomas W; Hammann, Mareike; Murray, David C; Murren, Courtney J; Strand, Allan E; Terada, Ryuta; Weinberger, Florian; Sotka, Erik E

    2016-08-01

    Baker's Law predicts uniparental reproduction will facilitate colonization success in novel habitats. While evidence supports this prediction among colonizing plants and animals, few studies have investigated shifts in reproductive mode in haplo-diplontic species in which both prolonged haploid and diploid stages separate meiosis and fertilization in time and space. Due to this separation, asexual reproduction can yield the dominance of one of the ploidy stages in colonizing populations. We tested for shifts in ploidy and reproductive mode across native and introduced populations of the red seaweed Gracilaria vermiculophylla. Native populations in the northwest Pacific Ocean were nearly always attached by holdfasts to hard substrata and, as is characteristic of the genus, haploid-diploid ratios were slightly diploid-biased. In contrast, along North American and European coastlines, introduced populations nearly always floated atop soft-sediment mudflats and were overwhelmingly dominated by diploid thalli without holdfasts. Introduced populations exhibited population genetic signals consistent with extensive vegetative fragmentation, while native populations did not. Thus, the ecological shift from attached to unattached thalli, ostensibly necessitated by the invasion of soft-sediment habitats, correlated with shifts from sexual to asexual reproduction and slight to strong diploid bias. We extend Baker's Law by predicting other colonizing haplo-diplontic species will show similar increases in asexuality that correlate with the dominance of one ploidy stage. Labile mating systems likely facilitate colonization success and subsequent range expansion, but for haplo-diplontic species, the long-term eco-evolutionary impacts will depend on which ploidy stage is lost and the degree to which asexual reproduction is canalized. © 2016 John Wiley & Sons Ltd.

  5. Concepts associated with a unified life cycle analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whelan, Gene; Peffers, Melissa S.; Tolle, Duane A.

    There is a risk associated with most things in the world, and all things have a life cycle unto themselves, even brownfields. Many components can be described by a''cycle of life.'' For example, five such components are life-form, chemical, process, activity, and idea, although many more may exist. Brownfields may touch upon several of these life cycles. Each life cycle can be represented as independent software; therefore, a software technology structure is being formulated to allow for the seamless linkage of software products, representing various life-cycle aspects. Because classes of these life cycles tend to be independent of each other,more » the current research programs and efforts do not have to be revamped; therefore, this unified life-cycle paradigm builds upon current technology and is backward compatible while embracing future technology. Only when two of these life cycles coincide and one impacts the other is there connectivity and a transfer of information at the interface. The current framework approaches (e.g., FRAMES, 3MRA, etc.) have a design that is amenable to capturing (1) many of these underlying philosophical concepts to assure backward compatibility of diverse independent assessment frameworks and (2) linkage communication to help transfer the needed information at the points of intersection. The key effort will be to identify (1) linkage points (i.e., portals) between life cycles, (2) the type and form of data passing between life cycles, and (3) conditions when life cycles interact and communicate. This paper discusses design aspects associated with a unified life-cycle analysis, which can support not only brownfields but also other types of assessments.« less

  6. Using a spatially structured life cycle model to assess the influence of multiple stressors on an exploited coastal-nursery-dependent population

    NASA Astrophysics Data System (ADS)

    Archambault, B.; Rivot, E.; Savina, M.; Le Pape, O.

    2018-02-01

    Exploited coastal-nursery-dependent fish species are subject to various stressors occurring at specific stages of the life cycle: climate-driven variability in hydrography determines the success of the first eggs/larvae stages; coastal nursery habitat suitability controls juvenile growth and survival; and fisheries target mostly adults. A life cycle approach was used to quantify the relative influence of these stressors on the Eastern English Channel (EEC) population of the common sole (Solea solea), a coastal-nursery-dependent flatfish population which sustains important fisheries. The common sole has a complex life cycle: after eggs hatch, larvae spend several weeks drifting in open water. Survivors go on to metamorphose into benthic fish. Juveniles spend the first two years of their life in coastal and estuarine nurseries. Close to maturation, they migrate to deeper areas, where different subpopulations supplied by different nurseries reproduce and are exploited by fisheries. A spatially structured age-and stage-based hierarchical Bayesian model integrating various aspects of ecological knowledge, data sources and expert knowledge was built to quantitatively describe this complex life cycle. The model included the low connectivity among three subpopulations in the EEC, the influence of hydrographic variability, the availability of suitable juvenile habitat and fisheries. Scenarios were designed to quantify the effects of interacting stressors on population renewal. Results emphasized the importance of coastal nursery habitat availability and quality for the population renewal. Realistic restoration scenarios of the highly degraded Seine estuary produced a two-third increase in catch potential for the adjacent subpopulation. Fisheries, however, remained the main source of population depletion. Setting fishing mortality to the maximum sustainable yield led to substantial increases in biomass (+100%) and catch (+33%) at the EEC scale. The approach also showed how

  7. Life Cycle of a Pencil.

    ERIC Educational Resources Information Center

    Reeske, Mike

    2000-01-01

    Explains a project called "Life Cycle of a Pencil" which was developed by the National Science Teachers Association (NSTA) and the U.S. Environmental Protection Agency (USEPA). Describes the life cycle of a pencil in stages starting from the first stage of design to the sixth stage of product disposal. (YDS)

  8. A case study by life cycle assessment

    NASA Astrophysics Data System (ADS)

    Li, Shuyun

    2017-05-01

    This article aims to assess the potential environmental impact of an electrical grinder during its life cycle. The Life Cycle Inventory Analysis was conducted based on the Simplified Life Cycle Assessment (SLCA) Drivers that calculated from the Valuation of Social Cost and Simplified Life Cycle Assessment Model (VSSM). The detailed results for LCI can be found under Appendix II. The Life Cycle Impact Assessment was performed based on Eco-indicator 99 method. The analysis results indicated that the major contributor to the environmental impact as it accounts for over 60% overall SLCA output. In which, 60% of the emission resulted from the logistic required for the maintenance activities. This was measured by conducting the hotspot analysis. After performing sensitivity analysis, it is evidenced that changing fuel type results in significant decrease environmental footprint. The environmental benefit can also be seen from the negative output values of the recycling activities. By conducting Life Cycle Assessment analysis, the potential environmental impact of the electrical grinder was investigated.

  9. The life history of the plant pathogen Pseudomonas syringae is linked to the water cycle.

    PubMed

    Morris, Cindy E; Sands, David C; Vinatzer, Boris A; Glaux, Catherine; Guilbaud, Caroline; Buffière, Alain; Yan, Shuangchun; Dominguez, Hélène; Thompson, Brian M

    2008-03-01

    Pseudomonas syringae is a plant pathogen well known for its capacity to grow epiphytically on diverse plants and for its ice-nucleation activity. The ensemble of its known biology and ecology led us to postulate that this bacterium is also present in non-agricultural habitats, particularly those associated with water. Here, we report the abundance of P. syringae in rain, snow, alpine streams and lakes and in wild plants, in addition to the previously reported abundance in epilithic biofilms. Each of these substrates harbored strains that corresponded to P. syringae in terms of biochemical traits, pathogenicity and pathogenicity-related factors and that were ice-nucleation active. Phylogenetic comparisons of sequences of four housekeeping genes of the non-agricultural strains with strains of P. syringae from disease epidemics confirmed their identity as P. syringae. Moreover, strains belonging to the same clonal lineage were isolated from snow, irrigation water and a diseased crop plant. Our data suggest that the different substrates harboring P. syringae modify the structure of the associated populations. Here, we propose a comprehensive life cycle for P. syringae--in agricultural and non-agricultural habitats--driven by the environmental cycle of water. This cycle opens the opportunity to evaluate the importance of non-agricultural habitats in the evolution of a plant pathogen and the emergence of virulence. The ice-nucleation activity of all strains from snow, unlike from other substrates, strongly suggests that P. syringae plays an active role in the water cycle as an ice nucleus in clouds.

  10. 10 CFR 436.12 - Life cycle cost methodology.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Life cycle cost methodology. 436.12 Section 436.12 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.12 Life cycle cost methodology. The life cycle cost methodology...

  11. 10 CFR 436.12 - Life cycle cost methodology.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Life cycle cost methodology. 436.12 Section 436.12 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.12 Life cycle cost methodology. The life cycle cost methodology...

  12. 10 CFR 436.12 - Life cycle cost methodology.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Life cycle cost methodology. 436.12 Section 436.12 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.12 Life cycle cost methodology. The life cycle cost methodology...

  13. 10 CFR 436.12 - Life cycle cost methodology.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life cycle cost methodology. 436.12 Section 436.12 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.12 Life cycle cost methodology. The life cycle cost methodology...

  14. 10 CFR 436.12 - Life cycle cost methodology.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Life cycle cost methodology. 436.12 Section 436.12 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.12 Life cycle cost methodology. The life cycle cost methodology...

  15. Life-cycle Economic and Environmental Effects of Green, Gray and Hybrid Stormwater Infrastructure

    NASA Astrophysics Data System (ADS)

    Stokes-Draut, J. R.; Taptich, M. N.; Horvath, A.

    2016-12-01

    Cities throughout the U.S. are seeking efficient ways to manage stormwater for many reasons, including flood control, pollution management, water supply augmentation and to prepare for a changing climate. Traditionally, cities have relied primarily on gray infrastructure, namely sewers, storage and treatment facilities. In these systems, urban runoff, its volume increasing as impervious surfaces expand, is channeled to a wastewater plant where it is mixed with raw sewage prior to treatment or it is discharged, generally untreated, to local water bodies. These facilities are inflexible and expensive to build and maintain. Many systems are deteriorating and/or approaching, if not exceeding, their design capacity. Increasingly, more innovative approaches that integrate stormwater management into the natural environment and that make sense at both local and regional scales are sought. Identifying the best stormwater solution will require evaluating the life-cycle economic costs associated with these alternatives, including costs associated with construction, operation, and maintenance including regulatory and permitting costs, financing, as well as other indirect costs (e.g., avoided wastewater processing or system capacity expansion, increased property value) and non-economic co-benefits (i.e, aesthetics, habitat provision). Beyond conventional life-cycle costing, applying life-cycle assessment (LCA) will contribute to more holistic and sustainable decision-making. LCA can be used to quantitatively track energy use, greenhouse gas emissions, and other environmental effects associated with constructing, operating, and maintaining green and gray infrastructure, including supply chain contributions. We will present the current state of knowledge for implementing life-cycle costing and LCA into stormwater management decisions for green, gray and hybrid infrastructure.

  16. Life cycle and reproduction of house-dust mites: environmental factors influencing mite populations.

    PubMed

    Hart, B J

    1998-01-01

    An understanding of the life cycle of house-dust mites, as well as environmental factors influencing mite populations, can be exploited in mite control. The most important limiting factor for house-dust-mite populations is air humidity. House-dust mites osmoregulate through the cuticle and therefore require a high ambient air humidity to prevent excessive water loss. In addition, the supracoxal glands actively take up ambient water vapour, and the protonynph stage of the life cycle is resistant to desiccation. Larger house-dust-mite populations are found when the absolute indoor air humidity is above 7 g/kg (45% relative humidity at 20 degrees C). Consequently, ventilation by air-conditioning systems is being developed as a means of control. A number of other aspects of the domestic environment are also being manipulated in an integrated approach to render the habitat less suitable for mites. The potential exists for developing models for house-dust mite populations, environmental characteristics, and the effects of various approaches to control.

  17. Life cycle management of analytical methods.

    PubMed

    Parr, Maria Kristina; Schmidt, Alexander H

    2018-01-05

    In modern process management, the life cycle concept gains more and more importance. It focusses on the total costs of the process from invest to operation and finally retirement. Also for analytical procedures an increasing interest for this concept exists in the recent years. The life cycle of an analytical method consists of design, development, validation (including instrumental qualification, continuous method performance verification and method transfer) and finally retirement of the method. It appears, that also regulatory bodies have increased their awareness on life cycle management for analytical methods. Thus, the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), as well as the United States Pharmacopeial Forum discuss the enrollment of new guidelines that include life cycle management of analytical methods. The US Pharmacopeia (USP) Validation and Verification expert panel already proposed a new General Chapter 〈1220〉 "The Analytical Procedure Lifecycle" for integration into USP. Furthermore, also in the non-regulated environment a growing interest on life cycle management is seen. Quality-by-design based method development results in increased method robustness. Thereby a decreased effort is needed for method performance verification, and post-approval changes as well as minimized risk of method related out-of-specification results. This strongly contributes to reduced costs of the method during its life cycle. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. 10 CFR 435.8 - Life-cycle costing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Life-cycle costing. 435.8 Section 435.8 Energy DEPARTMENT... BUILDINGS Mandatory Energy Efficiency Standards for Federal Low-Rise Residential Buildings. § 435.8 Life-cycle costing. Each Federal agency shall determine life-cycle cost-effectiveness by using the procedures...

  19. 10 CFR 435.8 - Life-cycle costing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life-cycle costing. 435.8 Section 435.8 Energy DEPARTMENT... BUILDINGS Mandatory Energy Efficiency Standards for Federal Low-Rise Residential Buildings. § 435.8 Life-cycle costing. Each Federal agency shall determine life-cycle cost-effectiveness by using the procedures...

  20. Multidisciplinary life cycle metrics and tools for green buildings.

    PubMed

    Helgeson, Jennifer F; Lippiatt, Barbara C

    2009-07-01

    Building sector stakeholders need compelling metrics, tools, data, and case studies to support major investments in sustainable technologies. Proponents of green building widely claim that buildings integrating sustainable technologies are cost effective, but often these claims are based on incomplete, anecdotal evidence that is difficult to reproduce and defend. The claims suffer from 2 main weaknesses: 1) buildings on which claims are based are not necessarily "green" in a science-based, life cycle assessment (LCA) sense and 2) measures of cost effectiveness often are not based on standard methods for measuring economic worth. Yet, the building industry demands compelling metrics to justify sustainable building designs. The problem is hard to solve because, until now, neither methods nor robust data supporting defensible business cases were available. The US National Institute of Standards and Technology (NIST) Building and Fire Research Laboratory is beginning to address these needs by developing metrics and tools for assessing the life cycle economic and environmental performance of buildings. Economic performance is measured with the use of standard life cycle costing methods. Environmental performance is measured by LCA methods that assess the "carbon footprint" of buildings, as well as 11 other sustainability metrics, including fossil fuel depletion, smog formation, water use, habitat alteration, indoor air quality, and effects on human health. Carbon efficiency ratios and other eco-efficiency metrics are established to yield science-based measures of the relative worth, or "business cases," for green buildings. Here, the approach is illustrated through a realistic building case study focused on different heating, ventilation, air conditioning technology energy efficiency. Additionally, the evolution of the Building for Environmental and Economic Sustainability multidisciplinary team and future plans in this area are described.

  1. 10 CFR 433.8 - Life-cycle costing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Life-cycle costing. 433.8 Section 433.8 Energy DEPARTMENT... FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH-RISE RESIDENTIAL BUILDINGS § 433.8 Life-cycle costing. Each Federal agency shall determine life-cycle cost-effectiveness by using the procedures set out in subpart A...

  2. 10 CFR 433.8 - Life-cycle costing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life-cycle costing. 433.8 Section 433.8 Energy DEPARTMENT... FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH-RISE RESIDENTIAL BUILDINGS § 433.8 Life-cycle costing. Each Federal agency shall determine life-cycle cost-effectiveness by using the procedures set out in subpart A...

  3. The Sphinx's Riddle: Life and Career Cycles.

    ERIC Educational Resources Information Center

    Burack, Elmer H.

    1984-01-01

    Career cycles should be considered apart from life cycles, even though the two are interrelated. This essay examines five theories about life and career cycles, and offers insights into their limitations and potential uses. (JB)

  4. A comparison of production system life cycle models

    NASA Astrophysics Data System (ADS)

    Attri, Rajesh; Grover, Sandeep

    2012-09-01

    Companies today need to keep up with the rapidly changing market conditions to stay competitive. The main issues in this paper are related to a company's market and its competitors. The prediction of market behavior is helpful for a manufacturing enterprise to build efficient production systems. However, these predictions are usually not reliable. A production system is required to adapt to changing markets, but such requirement entails higher cost. Hence, analyzing different life cycle models of the production system is necessary. In this paper, different life cycle models of the production system are compared to evaluate the distinctive features and the limitations of each model. Furthermore, the difference between product life cycle and production life cycle is summarized, and the effect of product life cycle on production life cycle is explained. Finally, a production system life cycle model, along with key activities to be performed in each stage, is proposed specifically for the manufacturing sector.

  5. A Few Meters Matter: Local Habitats Drive Reproductive Cycles in a Tropical Lizard.

    PubMed

    Otero, Luisa M; Huey, Raymond B; Gorman, George C

    2015-09-01

    Reproductive phenology often varies geographically within species, driven by environmental gradients that alter growth and reproduction. However, environments can differ between adjacent habitats at single localities. In lowland Puerto Rico, both open (sunny, warm) and forested (shady, cool) habitats may be only meters apart. The lizard Anolis cristatellus lives in both habitats: it thermoregulates carefully in the open but is a thermoconformer in the forest. To determine whether reproduction differs between habitats, we compared reproductive cycles of females in open versus forest habitats at two localities for over 2 years. Open females were more likely than forest females to be reproductive throughout the year, probably because open females were able to bask and thereby achieve warmer body temperatures. These between-habitat differences in reproduction were especially marked in cool months and are equivalent in magnitude to those between populations separated by elevation. Thus, environmental differences (even on a microlandscape scale) matter to reproduction and probably to demography.

  6. Life Cycle, Feeding and Production of Isoptena serricornis(Pictet, 1841)

    NASA Astrophysics Data System (ADS)

    Derka, Tomá; Tierno de Figueroa, José Manuel; Krno, Il'ja

    2004-05-01

    Some aspects of the biology and ecology (life cycle, feeding and production) of a population of Isoptena serricornis in the Rudava River (Slovakia) are studied, reported and discussed. The life cycle is annual, with slow growth in autumn-winter and fast growth in late summer and spring. The growth decreased two weeks before the Fall Equinox and increased two weeks after the Spring Equinox. The flight period spans from the end of May to the beginning of July. The presence of large sand particles in the gut of all studied nymphs is of note, and indicates that I. serricornis acts as a deposit-collector species. Nymphal food is principally composed of detritus, unicellular organisms and, in nymphs of intermediate or large size, Chironomidae larvae. Adult food is composed fundamentally of different types of pollen grains. Males usually have lower food content than females. Annual production of this species (694-750 mg · m-2) is very high in relation to other previously studied Chloroperlidae. This is probably largely responsible for I. serricornis being one of the most abundant components of the macroinvertebrate community in its habitat in the Rudava River. A negative correlation between production and temperature was observed.

  7. LIFE CYCLE ASSESSMENT: PRINCIPLES AND PRACTICE

    EPA Science Inventory

    The following document provides an introductory overview of Life Cycle Assessment (LCA) and describes the general uses and major components of LCA. This document is an update and merger of two previous EPA documents on LCA ("Life Cycle Assessment: Inventory Guidelines and Princip...

  8. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 3 2013-04-01 2013-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative dumping...

  9. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 3 2014-04-01 2014-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative dumping...

  10. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 3 2012-04-01 2012-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative dumping...

  11. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative dumping...

  12. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 3 2011-04-01 2011-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative dumping...

  13. Optimizing product life cycle processes in design phase

    NASA Astrophysics Data System (ADS)

    Faneye, Ola. B.; Anderl, Reiner

    2002-02-01

    Life cycle concepts do not only serve as basis in assisting product developers understand the dependencies between products and their life cycles, they also help in identifying potential opportunities for improvement in products. Common traditional concepts focus mainly on energy and material flow across life phases, necessitating the availability of metrics derived from a reference product. Knowledge of life cycle processes won from an existing product is directly reused in its redesign. Depending on sales volume nevertheless, the environmental impact before product optimization can be substantial. With modern information technologies today, computer-aided life cycle methodologies can be applied well before product use. On the basis of a virtual prototype, life cycle processes are analyzed and optimized, using simulation techniques. This preventive approach does not only help in minimizing (or even eliminating) environmental burdens caused by product, costs incurred due to changes in real product can also be avoided. The paper highlights the relationship between product and life cycle and presents a computer-based methodology for optimizing the product life cycle during design, as presented by SFB 392: Design for Environment - Methods and Tools at Technical University, Darmstadt.

  14. Modeling and simulation of an aquatic habitat for bioregenerative life support research

    NASA Astrophysics Data System (ADS)

    Drayer, Gregorio E.; Howard, Ayanna M.

    2014-01-01

    Long duration human spaceflight poses challenges for spacecraft autonomy and the regeneration of life support consumables, such as oxygen and water. Bioregenerative life support systems (BLSS), which make use of biological processes to transform biological byproducts back into consumables, have the ability to recycle organic byproducts and are the preferred option for food production. A limitation in BLSS research is in the non-availability of small-scale experimental capacities that may help to better understand the challenges in system closure, integration, and control. Ground-based aquatic habitats are an option for small-scale research relevant to bioregenerative life support systems (BLSS), given that they can operate as self-contained systems enclosing a habitat composed of various species in a single volume of water. The purpose of this paper is to present the modeling and simulation of a reconfigurable aquatic habitat for experiments in regenerative life support automation; it supports the use of aquatic habitats as a small-scale approach to experiments relevant to larger-scale regenerative life support systems. It presents ground-based aquatic habitats as an option for small-scale BLSS research focusing on the process of respiration, and elaborates on the description of biological processes by introducing models of ecophysiological phenomena for consumers and producers: higher plants of the species Bacopa monnieri produce O2 for snails of the genus Pomacea; the snails consume O2 and generate CO2, which is used by the plants in combination with radiant energy to generate O2 through the process of photosynthesis. Feedback controllers are designed to regulate the concentration of dissolved oxygen in the water. This paper expands the description of biological processes by introducing models of ecophysiological phenomena of the organisms involved. The model of the plants includes a description of the rate of CO2 assimilation as a function of irradiance

  15. Educational Focuses in Organisational Life Cycles.

    ERIC Educational Resources Information Center

    Miller, Harry G.

    1985-01-01

    Presents four stages frequently associated with the stages of an organization's life cycle: experimentation, growth, maturity, and decline or stability. The author also demonstrates that the impact of employment and thus training related to organizational life cycles suggests a need for understanding the technical preparation required for…

  16. Autonomy and integration in complex parasite life cycles.

    PubMed

    Benesh, Daniel P

    2016-12-01

    Complex life cycles are common in free-living and parasitic organisms alike. The adaptive decoupling hypothesis postulates that separate life cycle stages have a degree of developmental and genetic autonomy, allowing them to be independently optimized for dissimilar, competing tasks. That is, complex life cycles evolved to facilitate functional specialization. Here, I review the connections between the different stages in parasite life cycles. I first examine evolutionary connections between life stages, such as the genetic coupling of parasite performance in consecutive hosts, the interspecific correlations between traits expressed in different hosts, and the developmental and functional obstacles to stage loss. Then, I evaluate how environmental factors link life stages through carryover effects, where stressful larval conditions impact parasites even after transmission to a new host. There is evidence for both autonomy and integration across stages, so the relevant question becomes how integrated are parasite life cycles and through what mechanisms? By highlighting how genetics, development, selection and the environment can lead to interdependencies among successive life stages, I wish to promote a holistic approach to studying complex life cycle parasites and emphasize that what happens in one stage is potentially highly relevant for later stages.

  17. Emissions from photovoltaic life cycles.

    PubMed

    Fthenakis, Vasilis M; Kim, Hyung Chul; Alsema, Erik

    2008-03-15

    Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 2004-2006, this study presents the life-cycle greenhouse gas emissions, criteria pollutant emissions, and heavy metal emissions from four types of major commercial PV systems: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride. Life-cycle emissions were determined by employing average electricity mixtures in Europe and the United States during the materials and module production for each PV system. Among the current vintage of PV technologies, thin-film cadmium telluride (CdTe) PV emits the least amount of harmful air emissions as it requires the least amount of energy during the module production. However, the differences in the emissions between different PV technologies are very small in comparison to the emissions from conventional energy technologies that PV could displace. As a part of prospective analysis, the effect of PV breeder was investigated. Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.

  18. Fitness and Individuality in Complex Life Cycles.

    PubMed

    Herron, Matthew D

    2016-12-01

    Complex life cycles are common in the eukaryotic world, and they complicate the question of how to define individuality. Using a bottom-up, gene-centric approach, I consider the concept of fitness in the context of complex life cycles. I analyze the fitness effects of an allele (or a trait) on different biological units within a complex life history and how these effects drive evolutionary change within populations. Based on these effects, I attempt to construct a concept of fitness that accurately predicts evolutionary change in the context of complex life cycles.

  19. The Life Cycle of Everyday Stuff.

    ERIC Educational Resources Information Center

    Reeske, Mike; Ireton, Shirley Watt

    Life cycle assessment is an important tool for technology planning as solid waste disposal options dwindle and energy prices continue to increase. This guide investigates the life cycles of products. The activities in this book are suitable for secondary earth science, environmental science, physical science, or integrated science lessons. The…

  20. Mars polar cap: a habitat for elementary life1

    NASA Astrophysics Data System (ADS)

    Wallis, M. K.; Wickramasinghe, N. C.

    2009-04-01

    Ices in the Martian polar caps are potential habitats for various species of microorganisms. Salts in the ice and biological anti-freeze polymers maintain liquid in cracks in the ices far below 0°C, possibly down to the mean 220-240 K. Sub-surface microbial life is shielded from ultraviolet (UV) radiation, but could potentially be activated on south-facing slopes under the midday, midsummer Sun. Such life would be limited by low levels of vapour, little transport of nutrients, low light levels below a protective dirt-crust, frost accumulation at night and in shadows, and little if any active translocation of organisms. As in the Antarctic and in permafrost, movement to new habitats depends on geo-climatic changes, which for Mars's north polar cap occur on a 50 000 year scale, except for rare meteorite impacts.

  1. LIFE-CYCLE ASSESSMENT

    EPA Science Inventory

    Life Cycle Assessment, or LCA, is an environmental accounting and mangement approach that consider all the aspects of resource use and environmental releases associated with an industrial system from cradle-to-grave. Specifically, it is a holistic view of environmental interacti...

  2. NREL: U.S. Life Cycle Inventory Database Home Page

    Science.gov Websites

    U.S. Life-Cycle Inventory Database Buildings Research Photo of a green field with an ocean in the background. U.S. Life Cycle Inventory Database NREL and its partners created the U.S. Life Cycle Inventory (LCI) Database to help life cycle assessment (LCA) practitioners answer questions about environmental

  3. NREL: U.S. Life Cycle Inventory Database - User Poll

    Science.gov Websites

    User Poll In preparation for the 2009 U.S. Life Cycle Inventory (LCI) Data Stakeholder meeting, the interested in life cycle analysis. The results from that poll and information gathered from the stakeholders polling data and feedback from life cycle analysis supporters helped develop the U.S. Life Cycle Inventory

  4. Mosquito Life Cycle

    EPA Pesticide Factsheets

    Knowing the stages of the mosquito's life will help you prevent mosquitoes around your home and help you choose the right pesticides for your needs, if you decide to use them. All mosquito species go through four distinct stages during their live cycle.

  5. Life cycles and biomass allocation in seed- and ramet-derived plants of Cryptotaenia canadensis (Apicea), a monocarpic species of eastern North America

    Treesearch

    Tracy S. Hawkins; Jerry M. Baskin; Carol C. Baskin

    2005-01-01

    Life cycles, survivorship, and biomass allocation for seed- and ramet-derived plants of Cryptotaenia canadensis (L.) DC. were studied to determine if variation existed between plant derivations, and how these attributes contribute to persistence of the species within a temperate forest habitat. Seed-derived plants behaved as biennials, reproducing...

  6. Long Life Nickel Electrodes for a Nickel-hydrogen Cell: Cycle Life Tests

    NASA Technical Reports Server (NTRS)

    Lim, H. S.; Verzwyvelt, S. A.

    1984-01-01

    In order to develop a long life nickel electrode for a Ni/H2 cell, cycle life tests of nickel electrodes were carried out in Hi/H2 boiler plate cells. A 19 test cell matrix was made of various nickel electrode designs including three levels each of plaque mechanical strength, median pore size of the plaque, and active material loading. Test cells were cycled to the end of their life (0.5v) in a 45-minute low earth orbit cycle regime at 80% depth-of-discharge. The results show that the active material loading level affects the cycle life the most with the optimum loading at 1.6 g/cc void. Mechanical strength did not affect the cycle life noticeably in the bend strength range of 400 to 700 psi. The best plaque type appears to be one which is made of INCO nickel powder type 287 and has a median pore size of 13 micron.

  7. Long life nickel electrodes for a nickel-hydrogen cell: Cycle life tests

    NASA Technical Reports Server (NTRS)

    Lim, H. S.; Verzwyvelt, S. A.

    1985-01-01

    In order to develop a long life nickel electrode for a Ni/H2 cell, the cycle life of nickel electrodes was tested in Ni/H2 boiler plate cells. A 19 test cell matrix was made of various nickel electrode designs including three levels each of plaque mechanical strength, median pore size of the plaque, and active material loading. Test cells were cycled to the end of their life (0.5v) in a 45 minute low Earth orbit cycle regime at 80% depth-of-discharge. It is shown that the active material loading level affects the cycle life the most with the optimum loading at 1.6 g/cc void. Mechanical strength does not affect the cycle life noticeably in the bend strength range of 400 to 700 psi. It is found that the best plaque is made of INCO nickel powder type 287 and has median pore size of 13 micron.

  8. Life history comparison of two terrestrial isopods in relation to habitat specialization

    NASA Astrophysics Data System (ADS)

    Quadros, Aline Ferreira; Caubet, Yves; Araujo, Paula Beatriz

    2009-03-01

    For many animal species, there is a relationship between life history strategies, as predicted by the r- K-selection theory, degree of habitat specialization and response to habitat alteration and loss. Here we compare two sympatric woodlice species with contrasting patterns of habitat use and geographical distribution. We predict that Atlantoscia floridana (Philosciidae), considered a habitat generalist, would exhibit the r-selected traits, whereas Balloniscus glaber (Balloniscidae), considered a habitat specialist, should have the K-selected traits. We analyzed several life history traits as well as life and fecundity tables using 715 and 842 females of A. floridana and B. glaber, respectively, from populations living in syntopy in southern Brazil. As predicted, most evaluated traits allow A. floridana to be considered an r-strategist and B. glaber a K-strategist: A. floridana showed a shorter lifetime, faster development, earlier reproduction, a smaller parental investment, higher net reproductive rate ( R0), a higher growth rate ( r) and a shorter generation time ( T) in comparison to B. glaber. A. floridana seems to be a successful colonizer with a high reproductive output. These characteristics explain its local abundance, commonness and wide geographical distribution. On the contrary, B. glaber has a restricted geographical distribution that is mainly associated with Atlantic forest fragments, a biome threatened by deforestation and replacement by monocultures. Its narrow distribution combined with the K-selected traits may confer to this species an increased extinction risk.

  9. Each life stage matters: the importance of assessing the response to climate change over the complete life cycle in butterflies.

    PubMed

    Radchuk, Viktoriia; Turlure, Camille; Schtickzelle, Nicolas

    2013-01-01

    As ectothermic organisms, butterflies have widely been used as models to explore the predicted impacts of climate change. However, most studies explore only one life stage; to our best knowledge, none have integrated the impact of temperature on the vital rates of all life stages for a species of conservation concern. Besides, most population viability analysis models for butterflies are based on yearly population growth rate, precluding the implementation and assessment of important climate change scenarios, where climate change occurs mainly, or differently, during some seasons. Here, we used a combination of laboratory and field experiments to quantify the impact of temperature on all life stages of a vulnerable glacial relict butterfly. Next, we integrated these impacts into an overall population response using a deterministic periodic matrix model and explored the impact of several climate change scenarios. Temperature positively affected egg, pre-diapause larva and pupal survival, and the number of eggs laid by a female; only the survival of overwintering larva was negatively affected by an increase in temperature. Despite the positive impact of warming on many life stages, population viability was reduced under all scenarios, with predictions of much shorter times to extinction than under the baseline (current temperature situation) scenario. Indeed, model predictions were the most sensitive to changes in survival of overwintering larva, the only stage negatively affected by warming. A proper consideration of every stage of the life cycle is important when designing conservation guidelines in the light of climate change. This is in line with the resource-based habitat view, which explicitly refers to the habitat as a collection of resources needed for all life stages of the species. We, therefore, encourage adopting a resource-based habitat view for population viability analysis and development of conservation guidelines for butterflies, and more generally

  10. 10 CFR 455.64 - Life-cycle cost methodology.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Life-cycle cost methodology. 455.64 Section 455.64 Energy..., Hospitals, Units of Local Government, and Public Care Institutions § 455.64 Life-cycle cost methodology. (a) The life-cycle cost methodology under § 455.63(b) of this part is a systematic comparison of the...

  11. 10 CFR 455.64 - Life-cycle cost methodology.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life-cycle cost methodology. 455.64 Section 455.64 Energy..., Hospitals, Units of Local Government, and Public Care Institutions § 455.64 Life-cycle cost methodology. (a) The life-cycle cost methodology under § 455.63(b) of this part is a systematic comparison of the...

  12. An Integrated Approach to Life Cycle Analysis

    NASA Technical Reports Server (NTRS)

    Chytka, T. M.; Brown, R. W.; Shih, A. T.; Reeves, J. D.; Dempsey, J. A.

    2006-01-01

    Life Cycle Analysis (LCA) is the evaluation of the impacts that design decisions have on a system and provides a framework for identifying and evaluating design benefits and burdens associated with the life cycles of space transportation systems from a "cradle-to-grave" approach. Sometimes called life cycle assessment, life cycle approach, or "cradle to grave analysis", it represents a rapidly emerging family of tools and techniques designed to be a decision support methodology and aid in the development of sustainable systems. The implementation of a Life Cycle Analysis can vary and may take many forms; from global system-level uncertainty-centered analysis to the assessment of individualized discriminatory metrics. This paper will focus on a proven LCA methodology developed by the Systems Analysis and Concepts Directorate (SACD) at NASA Langley Research Center to quantify and assess key LCA discriminatory metrics, in particular affordability, reliability, maintainability, and operability. This paper will address issues inherent in Life Cycle Analysis including direct impacts, such as system development cost and crew safety, as well as indirect impacts, which often take the form of coupled metrics (i.e., the cost of system unreliability). Since LCA deals with the analysis of space vehicle system conceptual designs, it is imperative to stress that the goal of LCA is not to arrive at the answer but, rather, to provide important inputs to a broader strategic planning process, allowing the managers to make risk-informed decisions, and increase the likelihood of meeting mission success criteria.

  13. NREL: U.S. Life Cycle Inventory Database - Publications

    Science.gov Websites

    Publications Planning Documents U.S. Life Cycle Inventory Database Roadmap, February 2009 U.S. Life Cycle Inventory User Survey, February 2009 U.S. LCI Database Factsheet, March 2005 User's Guide for Life

  14. From life cycle talking to taking action

    EPA Science Inventory

    The series of Life Cycle Management (LCM) conferences has aimed to create a platform for users and developers of life cycle assessment tools to share their experiences as they challenge traditional environmental management practices, which are narrowly confined (“gate-to-gate”) a...

  15. Identification of Wild Boar-Habitat Epidemiologic Cycle in African Swine Fever Epizootic.

    PubMed

    Chenais, Erika; Ståhl, Karl; Guberti, Vittorio; Depner, Klaus

    2018-04-01

    The African swine fever epizootic in central and eastern European Union member states has a newly identified component involving virus transmission by wild boar and virus survival in the environment. Insights led to an update of the 3 accepted African swine fever transmission models to include a fourth cycle: wild boar-habitat.

  16. Development and infectious disease in hosts with complex life cycles.

    PubMed

    Searle, Catherine L; Xie, Gisselle Yang; Blaustein, Andrew R

    2013-01-01

    Metamorphosis is often characterized by profound changes in morphology and physiology that can affect the dynamics of species interactions. For example, the interaction between a pathogen and its host may differ depending on the life stage of the host or pathogen. One pathogen that infects hosts with complex life cycles is the emerging fungal pathogen of amphibians, Batrachochytrium dendrobatidis (Bd). We sought to determine how conditions at the larval stage can affect variation in development and patterns of Bd infection across amphibian life stages. We used outdoor experimental mesocosms to simulate natural pond habitats and manipulated the presence of Bd, the larval density, and the number of host species in larvae of two co-occurring amphibian species (Rana cascadae and Pseudacris regilla). We found that infection differed between species throughout development; P. regilla consistently had higher infection severity compared to R. cascadae. Additionally, while up to 100% of larvae were infected, only 18.2% of R. cascadae and 81.5% of P. regilla were infected after metamorphosis. This indicates that amphibians have the ability to recover from Bd infection as they undergo metamorphosis. Higher larval densities in P. regilla led to a shorter larval period, and individuals with a shorter larval period had lower infection severity. This led to a trend where P. regilla larvae reared at high densities tended to have lower infection prevalence after metamorphosis. We also found that exposure to Bd increased larval mortality and prolonged the larval period in P. regilla, indicating that P. regilla are susceptible to the negative effects of Bd as larvae. This study demonstrates that host density, species composition, and pathogen exposure may all interact to influence development and infection in hosts with complex life cycles.

  17. Snow as a habitat for microorganisms

    NASA Technical Reports Server (NTRS)

    Hoham, Ronald W.

    1989-01-01

    There are three major habitats involving ice and snow, and the microorganisms studied from these habitats are most eukaryotic. Sea ice is inhabited by algae called diatoms, glacial ice has sparse populations of green algai cal desmids, and the temporary and permanent snows in mountainous regions and high latitudes are inhabited mostly by green algal flagellates. The life cycle of green algal flagellates is summarized by discussing the effects of light, temperature, nutrients, and snow melts. Specific examples of optimal conditions and environmental effects for various snow algae are given. It is not likely that the eukaryotic snow algae presented are candidated for life on the planet Mars. Evolutionally, eukaryotic cells as know on Earth may not have had the opportunity to develop on Mars (if life evolved at all on Mars) since eukaryotes did not appear on Earth until almost two billion years after the first prokaryotic organisms. However, the snow/ice ecosystems on Earth present themselves as extreme habitats were there is evidence of prokaryotic life (eubacteria and cyanbacteria) of which literally nothing is known. Any future surveillances of extant and/or extinct life on Mars should include probes (if not landing sites) to investigate sites of concentrations of ice water. The possibility of signs of life in Martian polar regions should not be overlooked.

  18. Unusual larval habitats and life history of chironomid (Diptera) genera

    USGS Publications Warehouse

    Hudson, Patrick L.

    1987-01-01

    Ninety-three genera, representing all subfamilies of Chironomidae, are organized into 9 categories of unusual habitats or life history including hygropetric, riparian (bank, floodplain, upland), hyporheic, symbiotic, and intertidal; others live in water held in plants or mine into unusual substrates. In riparian zones precise location of optimum habitat is difficult to determine as is definition of habitat within the continuum from shoreline to upland areas. The ecological importance of the riparian group appears to lie in its processing of coarse particulate matter along the floodplain of streams and rivers. All riparian genera are zoogeographically useful and can be used in reconstructing evolutionary dispersal pathways because they are adapted to unique habits that have remained largely undisturbed by human activities.

  19. Identification of Wild Boar–Habitat Epidemiologic Cycle in African Swine Fever Epizootic

    PubMed Central

    Ståhl, Karl; Guberti, Vittorio; Depner, Klaus

    2018-01-01

    The African swine fever epizootic in central and eastern European Union member states has a newly identified component involving virus transmission by wild boar and virus survival in the environment. Insights led to an update of the 3 accepted African swine fever transmission models to include a fourth cycle: wild boar–habitat. PMID:29553337

  20. Transitions during cephalopod life history: the role of habitat, environment, functional morphology and behaviour.

    PubMed

    Robin, Jean-Paul; Roberts, Michael; Zeidberg, Lou; Bloor, Isobel; Rodriguez, Almendra; Briceño, Felipe; Downey, Nicola; Mascaró, Maite; Navarro, Mike; Guerra, Angel; Hofmeister, Jennifer; Barcellos, Diogo D; Lourenço, Silvia A P; Roper, Clyde F E; Moltschaniwskyj, Natalie A; Green, Corey P; Mather, Jennifer

    2014-01-01

    Cephalopod life cycles generally share a set of stages that take place in different habitats and are adapted to specific, though variable, environmental conditions. Throughout the lifespan, individuals undertake a series of brief transitions from one stage to the next. Four transitions were identified: fertilisation of eggs to their release from the female (1), from eggs to paralarvae (2), from paralarvae to subadults (3) and from subadults to adults (4). An analysis of each transition identified that the changes can be radical (i.e. involving a range of morphological, physiological and behavioural phenomena and shifts in habitats) and critical (i.e. depending on environmental conditions essential for cohort survival). This analysis underlines that transitions from eggs to paralarvae (2) and from paralarvae to subadults (3) present major risk of mortality, while changes in the other transitions can have evolutionary significance. This synthesis suggests that more accurate evaluation of the sensitivity of cephalopod populations to environmental variation could be achieved by taking into account the ontogeny of the organisms. The comparison of most described species advocates for studies linking development and ecology in this particular group. © 2014 Elsevier Ltd All rights reserved.

  1. Evolution and regulation of complex life cycles: a brown algal perspective.

    PubMed

    Cock, J Mark; Godfroy, Olivier; Macaisne, Nicolas; Peters, Akira F; Coelho, Susana M

    2014-02-01

    The life cycle of an organism is one of its fundamental features, influencing many aspects of its biology. The brown algae exhibit a diverse range of life cycles indicating that transitions between life cycle types may have been key adaptive events in the evolution of this group. Life cycle mutants, identified in the model organism Ectocarpus, are providing information about how life cycle progression is regulated at the molecular level in brown algae. We explore some of the implications of the phenotypes of the life cycle mutants described to date and draw comparisons with recent insights into life cycle regulation in the green lineage. Given the importance of coordinating growth and development with life cycle progression, we suggest that the co-option of ancient life cycle regulators to control key developmental events may be a common feature in diverse groups of multicellular eukaryotes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Landscape-scale Habitat Templates and Life Histories of Endangered and Invasive Fish Species in Large Rivers of the Mid-Continent USA (Invited)

    NASA Astrophysics Data System (ADS)

    Jacobson, R. B.; Braaten, P. J.; Chapman, D.; DeLonay, A. J.

    2013-12-01

    Many fish species migrate through river systems to complete their life cycles, occupying specific habitats during specific life stages. Regional geomorphology sets a template for their habitat-use patterns and ontogenetic development. In large rivers of the Mid-continent USA, understanding of relations of fish life histories to landscape-scale habitat templates informs recovery of endangered species and prevention of spread of invasive species. The endangered pallid sturgeon has evolved in the Missouri-Mississippi river system over 150 Ma. Its present-day distribution probably results from extensive drainage re-arrangements during the Pleistocene, followed by contemporary fragmentation. The reproductive and early life-stage needs of pallid sturgeon encompass hundreds of km, as adults migrate upstream to spawn and free embryos and larvae disperse downstream. Spawning requires coarse, hard substrate for incubation of adhesive eggs but adult pallid sturgeon are found predominately over sand, indicating that coarse substrate is a critical but transient habitat need. Once hatched, free-embryos initiate 9-17 days of downstream dispersal that distributes them over several hundreds of km. Lotic conditions at the dispersal terminus are required for survival. Persistent recruitment failure has been attributed to dams and channelization, which have fragmented migration and dispersal corridors, altered flow regimes, and diminished rearing habitats. Key elements of the natural history of this species remain poorly understood because adults are rare and difficult to observe, while the earliest life stages are nearly undetectable. Recent understanding has been accelerated using telemetry and hydroacoustics, but such assessments occur in altered systems and may not be indicative of natural behaviors. Restoration activities attempt - within considerable uncertainty -- to restore elements of the habitat template where they are needed. In comparison, invasive Asian carps have been

  3. 10 CFR 434.607 - Life cycle cost analysis criteria.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Life cycle cost analysis criteria. 434.607 Section 434.607... HIGH RISE RESIDENTIAL BUILDINGS Building Energy Compliance Alternative § 434.607 Life cycle cost analysis criteria. 607.1 The following life cycle cost criteria applies to the fuel selection requirements...

  4. 10 CFR 434.607 - Life cycle cost analysis criteria.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life cycle cost analysis criteria. 434.607 Section 434.607... HIGH RISE RESIDENTIAL BUILDINGS Building Energy Compliance Alternative § 434.607 Life cycle cost analysis criteria. 607.1 The following life cycle cost criteria applies to the fuel selection requirements...

  5. Riverine habitat dynamics

    USGS Publications Warehouse

    Jacobson, R.B.

    2013-01-01

    The physical habitat template is a fundamental influence on riverine ecosystem structure and function. Habitat dynamics refers to the variation in habitat through space and time as the result of varying discharge and varying geomorphology. Habitat dynamics can be assessed at spatial scales ranging from the grain (the smallest resolution at which an organism relates to its environment) to the extent (the broadest resolution inclusive of all space occupied during its life cycle). In addition to a potentially broad range of spatial scales, assessments of habitat dynamics may include dynamics of both occupied and nonoccupied habitat patches because of process interactions among patches. Temporal aspects of riverine habitat dynamics can be categorized into hydrodynamics and morphodynamics. Hydrodynamics refers to habitat variation that results from changes in discharge in the absence of significant change of channel morphology and at generally low sediment-transport rates. Hydrodynamic assessments are useful in cases of relatively high flow exceedance (percent of time a flow is equaled or exceeded) or high critical shear stress, conditions that are applicable in many studies of instream flows. Morphodynamics refers to habitat variation resulting from changes to substrate conditions or channel/floodplain morphology. Morphodynamic assessments are necessary when channel and floodplain boundary conditions have been significantly changed, generally by relatively rare flood events or in rivers with low critical shear stress. Morphodynamic habitat variation can be particularly important as disturbance mechanisms that mediate population growth or for providing conditions needed for reproduction, such as channel-migration events that erode cutbanks and provide new pointbar surfaces for germination of riparian trees. Understanding of habitat dynamics is increasing in importance as societal goals shift toward restoration of riverine ecosystems. Effective investment in restoration

  6. Life Cycle Costing in Government Procurement.

    DTIC Science & Technology

    1985-05-01

    in many areas continue to do so today. However, as business decisions grow in complexity the "gut" reaction approach to minimizing the total costs of...predictors of future events) in 0 determining the most cost effectiv- approach to future - operations. Under "classic" life cycle costing the concepts of... in the FAR and occasional references appear to include life cycle costs within price.8 However in practice , use of the word

  7. A life cycle database for parasitic acanthocephalans, cestodes, and nematodes

    USGS Publications Warehouse

    Benesh, Daniel P.; Lafferty, Kevin D.; Kuris, Armand

    2017-01-01

    Parasitologists have worked out many complex life cycles over the last ~150 years, yet there have been few efforts to synthesize this information to facilitate comparisons among taxa. Most existing host-parasite databases focus on particular host taxa, do not distinguish final from intermediate hosts, and lack parasite life-history information. We summarized the known life cycles of trophically transmitted parasitic acanthocephalans, cestodes, and nematodes. For 973 parasite species, we gathered information from the literature on the hosts infected at each stage of the parasite life cycle (8510 host-parasite species associations), what parasite stage is in each host, and whether parasites need to infect certain hosts to complete the life cycle. We also collected life-history data for these parasites at each life cycle stage, including 2313 development time measurements and 7660 body size measurements. The result is the most comprehensive data summary available for these parasite taxa. In addition to identifying gaps in our knowledge of parasite life cycles, these data can be used to test hypotheses about life cycle evolution, host specificity, parasite life-history strategies, and the roles of parasites in food webs.

  8. The habitat and nature of early life.

    PubMed

    Nisbet, E G; Sleep, N H

    2001-02-22

    Earth is over 4,500 million years old. Massive bombardment of the planet took place for the first 500-700 million years, and the largest impacts would have been capable of sterilizing the planet. Probably until 4,000 million years ago or later, occasional impacts might have heated the ocean over 100 degrees C. Life on Earth dates from before about 3,800 million years ago, and is likely to have gone through one or more hot-ocean 'bottlenecks'. Only hyperthermophiles (organisms optimally living in water at 80-110 degrees C) would have survived. It is possible that early life diversified near hydrothermal vents, but hypotheses that life first occupied other pre-bottleneck habitats are tenable (including transfer from Mars on ejecta from impacts there). Early hyperthermophile life, probably near hydrothermal systems, may have been non-photosynthetic, and many housekeeping proteins and biochemical processes may have an original hydrothermal heritage. The development of anoxygenic and then oxygenic photosynthesis would have allowed life to escape the hydrothermal setting. By about 3,500 million years ago, most of the principal biochemical pathways that sustain the modern biosphere had evolved, and were global in scope.

  9. Habitat-specific differences alter traditional biogeographic patterns of life history in a climate-change induced range expansion.

    PubMed

    Riley, Megan E; Griffen, Blaine D

    2017-01-01

    Range shifts and expansions resulting from global climate change have the potential to create novel communities with unique plant-animal interactions. Organisms expanding their range into novel biotic and abiotic environments may encounter selection pressures that alter traditional biogeographic patterns of life history traits. Here, we used field surveys to examine latitudinal patterns of life history traits in a broadly distributed ectotherm (mangrove tree crab Aratus pisonii) that has recently experienced a climate change-induced range expansion into a novel habitat type. Additionally, we conducted laboratory and field experiments to investigate characteristics associated with these life history traits (e.g. fecundity, offspring quality, and potential selection pressures). We compared these characteristics in native mangrove habitats in which the species has historically dwelled and novel salt marsh habitats into which the species has recently expanded its range. Consistent with traditional biogeographic concepts (i.e. Bergmann's clines), size at maturity and mean body size of reproductive females increased with latitude within the native habitat. However, they decreased significantly in novel habitats at the highest latitudes of the species' range, which was consistent with habitat-specific differences in both biotic (predation) and abiotic (temperature) selection pressures. Although initial maternal investment (egg volume and weight) did not differ between habitats, fecundity was lower in novel habitats as a result of differences in size at reproduction. Offspring quality, as measured by larval starvation resistance, was likewise diminished in novel habitats relative to native habitats. These differences in offspring quality may have enduring consequences for species success and persistence in novel habitats. Life history characteristics such as those investigated here are fundamental organismal traits; consequently, understanding the potential impacts of

  10. Evolution and maintenance of haploid-diploid life cycles in natural populations: The case of the marine brown alga Ectocarpus.

    PubMed

    Couceiro, Lucía; Le Gac, Mickael; Hunsperger, Heather M; Mauger, Stéphane; Destombe, Christophe; Cock, J Mark; Ahmed, Sophia; Coelho, Susana M; Valero, Myriam; Peters, Akira F

    2015-07-01

    The evolutionary stability of haploid-diploid life cycles is still controversial. Mathematical models indicate that niche differences between ploidy phases may be a necessary condition for the evolution and maintenance of these life cycles. Nevertheless, experimental support for this prediction remains elusive. In the present work, we explored this hypothesis in natural populations of the brown alga Ectocarpus. Consistent with the life cycle described in culture, Ectocarpus crouaniorum in NW France and E. siliculosus in SW Italy exhibited an alternation between haploid gametophytes and diploid sporophytes. Our field data invalidated, however, the long-standing view of an isomorphic alternation of generations. Gametophytes and sporophytes displayed marked differences in size and, conforming to theoretical predictions, occupied different spatiotemporal niches. Gametophytes were found almost exclusively on the alga Scytosiphon lomentaria during spring whereas sporophytes were present year-round on abiotic substrata. Paradoxically, E. siliculosus in NW France exhibited similar habitat usage despite the absence of alternation of ploidy phases. Diploid sporophytes grew both epilithically and epiphytically, and this mainly asexual population gained the same ecological advantage postulated for haploid-diploid populations. Consequently, an ecological interpretation of the niche differences between haploid and diploid individuals does not seem to satisfactorily explain the evolution of the Ectocarpus life cycle. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  11. Life Cycle Assessment Harmonization | Energy Analysis | NREL

    Science.gov Websites

    change are excluded from this analysis. The data showed that life cycle greenhouse gas (GHG) emissions Sensitivity Analysis of Biopower Life-Cycle Assessments and Greenhouse Gas Emission, Electric Power Research hydropower, ocean, geothermal, biopower, solar, wind, nuclear, coal, and natural gas technologies. See the

  12. The life cycle of centrioles.

    PubMed

    Hatch, E; Stearns, T

    2010-01-01

    Centrioles organize the centrosome and nucleate the ciliary axoneme, and the centriole life cycle has many parallels to the chromosome cycle. The centriole cycle in animals begins at fertilization with the contribution of two centrioles by the male gamete. In the ensuing cell cycles, the duplication of centrioles is controlled temporally, spatially, and numerically. As a consequence of the duplication mechanism, the two centrioles in a typical interphase cell are of different ages and have different functions. Here, we discuss how new centrioles are assembled, what mechanisms limit centriole number, and the consequences of the inherent asymmetry of centriole duplication and segregation.

  13. Modeling Net Land Occupation of Hydropower Reservoirs in Norway for Use in Life Cycle Assessment.

    PubMed

    Dorber, Martin; May, Roel; Verones, Francesca

    2018-02-20

    Increasing hydropower electricity production constitutes a unique opportunity to mitigate climate change impacts. However, hydropower electricity production also impacts aquatic and terrestrial biodiversity through freshwater habitat alteration, water quality degradation, and land use and land use change (LULUC). Today, no operational model exists that covers any of these cause-effect pathways within life cycle assessment (LCA). This paper contributes to the assessment of LULUC impacts of hydropower electricity production in Norway in LCA. We quantified the inundated land area associated with 107 hydropower reservoirs with remote sensing data and related it to yearly electricity production. Therewith, we calculated an average net land occupation of 0.027 m 2 ·yr/kWh of Norwegian storage hydropower plants for the life cycle inventory. Further, we calculated an adjusted average land occupation of 0.007 m 2 ·yr/kWh, accounting for an underestimation of water area in the performed maximum likelihood classification. The calculated land occupation values are the basis to support the development of methods for assessing the land occupation impacts of hydropower on biodiversity in LCA at a damage level.

  14. Managing the Life Cycle Risks of Nanomaterials

    DTIC Science & Technology

    2009-07-01

    ISO International Organization for Standardization ISN Institute for Soldier Nanotechnologies LCA Life Cycle Assessment LCCA Life Cycle Cost Analysis...similar to their smaller Existing ISO /TS 27687:2008 Nanotechnologies -- Terminology and definitions for nano-objects -- Nanoparticle, nanofibre and...Nanotechnology Under Development ISO /CD TR 80004-1 Nanotechnologies - Terminology and definitions – Framework ISO /AWI TS 80004-2 Nanotechnologies

  15. Comparing the Life Cycle Energy Consumption, Global ...

    EPA Pesticide Factsheets

    Managing the water-energy-nutrient nexus for the built environment requires, in part, a full system analysis of energy consumption, global warming and eutrophication potentials of municipal water services. As an example, we evaluated the life cycle energy use, greenhouse gas (GHG) emissions and aqueous nutrient releases of the whole anthropogenic municipal water cycle starting from raw water extraction to wastewater treatment and reuse/discharge for five municipal water and wastewater systems. The assessed options included conventional centralized services and four alternative options following the principles of source-separation and water fit-for-purpose. The comparative life cycle assessment identified that centralized drinking water supply coupled with blackwater energy recovery and on-site greywater treatment and reuse was the most energyand carbon-efficient water service system evaluated, while the conventional (drinking water and sewerage) centralized system ranked as the most energy- and carbon-intensive system. The electricity generated from blackwater and food residuals co-digestion was estimated to offset at least 40% of life cycle energy consumption for water/waste services. The dry composting toilet option demonstrated the lowest life cycle eutrophication potential. The nutrients in wastewater effluent are the dominating contributors for the eutrophication potential for the assessed system configurations. Among the parameters for which variability

  16. A Life Cycle Cost Analysis of Rigid Pavements

    DOT National Transportation Integrated Search

    1999-09-01

    The Texas Department of Transportation (TxDOT)commissioned a research project in 1996, summarized here, to promote life cycle cost analysis of rigid pavements throughout the TxDOT districts by developing a uniform methodology for performing life cycl...

  17. Life Cycle Impact Assessment Research Developments and Needs

    EPA Science Inventory

    Life Cycle Impact Assessment (LCIA) developments are explained along with key publications which record discussions which comprised ISO 14042 and SETAC document development, UNEP SETAC Life Cycle Initiative research, and research from public and private research institutions. It ...

  18. Evolution in the Cycles of Life.

    PubMed

    Bowman, John L; Sakakibara, Keiko; Furumizu, Chihiro; Dierschke, Tom

    2016-11-23

    The life cycles of eukaryotes alternate between haploid and diploid phases, which are initiated by meiosis and gamete fusion, respectively. In both ascomycete and basidiomycete fungi and chlorophyte algae, the haploid-to-diploid transition is regulated by a pair of paralogous homeodomain protein encoding genes. That a common genetic program controls the haploid-to-diploid transition in phylogenetically disparate eukaryotic lineages suggests this may be the ancestral function for homeodomain proteins. Multicellularity has evolved independently in many eukaryotic lineages in either one or both phases of the life cycle. Organisms, such as land plants, exhibiting a life cycle whereby multicellular bodies develop in both the haploid and diploid phases are often referred to as possessing an alternation of generations. We review recent progress on understanding the genetic basis for the land plant alternation of generations and highlight the roles that homeodomain-encoding genes may have played in the evolution of complex multicellularity in this lineage.

  19. KOH concentration effect on cycle life of nickel-hydrogen cells

    NASA Technical Reports Server (NTRS)

    Lim, Hong S.; Verzwyvelt, S. A.

    1987-01-01

    A cycle life test of Ni/H2 cells containing electrolytes of various KOH concentrations and a sintered type nickel electrode was carried out at 23 C using a 45 min accelerated low Earth orbit (LEO) cycle regime at 80 percent depth of discharge. One of three cells containing 26 percent KOH has achieved over 28,000 cycles, and the other two 19,000 cycles, without a sign of failure. Two other cells containing 31 percent KOH electrolyte, which is the concentration presently used in aerospace cells, failed after 2,979 and 3,620 cycles. This result indicates that the cycle life of the present type of Ni/H2 cells may be extended by a factor of 5 to 10 simply by lowering the KOH concentration. Long cycle life of a Ni/H2 battery at high depth-of-discharge operation is desired, particularly for an LEO spacecraft application. Typically, battery life of about 30,000 cycles is required for a five year mission in an LEO. Such a cycle life with presently available cells can be assured only at a very low depth-of-discharge operation. Results of testing already show that the cycle life of an Ni/H2 cell is tremendously improved by simply using an electrolyte of low KOH concentration.

  20. Life Cycle. K-6 Science Curriculum.

    ERIC Educational Resources Information Center

    Blueford, J. R.; And Others

    Life Cycle is one of the units of a K-6 unified science curriculum program. The unit consists of four organizing sub-themes: (1) past life (focusing on dinosaurs and fossil formation, types, and importance); (2) animal life (examining groups of invertebrates and vertebrates, cells, reproduction, and classification systems); (3) plant life…

  1. All about Animal Life Cycles. Animal Life for Children. [Videotape].

    ERIC Educational Resources Information Center

    2000

    While watching the development from tadpole to frog, caterpillar to butterfly, and pup to wolf, children learn about the life cycles of animals, the different stages of development, and the average life spans of a variety of creatures. This videotape correlates to the following National Science Education Standards for Life Science: characteristics…

  2. Computer Software for Life Cycle Cost.

    DTIC Science & Technology

    1987-04-01

    34 111. 1111I .25 IL4 jj 16 MICROCOPY RESOLUTION TEST CHART hut FILE C AIR CoMMNAMN STFF COLLG STUJDET PORTO i COMpUTER SOFTWARE FOR LIFE CYCLE CO879...obsolete), physical life (utility before physically wearing out), or application life (utility in a given function)." (7:5) The costs are usually

  3. US Federal LCA Commons Life Cycle Inventory Unit Process Template

    EPA Science Inventory

    The US Federal LCA Commons Life Cycle Inventory Unit Process Template is a multi-sheet Excel template for life cycle inventory data, metadata and other documentation. The template comes as a package that consistent of three parts: (1) the main template itself for life cycle inven...

  4. Software security checklist for the software life cycle

    NASA Technical Reports Server (NTRS)

    Gilliam, D. P.; Wolfe, T. L.; Sherif, J. S.

    2002-01-01

    A formal approach to security in the software life cycle is essential to protect corporate resources. However, little thought has been given to this aspect of software development. Due to its criticality, security should be integrated as a formal approach in the software life cycle.

  5. LIFE CYCLE DESIGN OF AMORPHOUS SILICON PHOTOVOLTAIC MODULES

    EPA Science Inventory

    The life cycle design framework was applied to photovoltaic module design. The primary objective of this project was to develop and evaluate design metrics for assessing and guiding the Improvement of PV product systems. Two metrics were used to assess life cycle energy perform...

  6. PRODUCT LIFE-CYCLE ASSESSMENT: INVENTORY GUIDELINES AND PRINCIPLES

    EPA Science Inventory

    The Life Cycle Assessment (LCA) can be used as an objective technical tool to evaluate the environmental consequences of a product, process, or activity holistically, across its entire life cycle. omplete LCA can be viewed as consisting of three complementary components (1) the i...

  7. EDITORIAL: THE INTERNATIONAL CONFERENCE ON LIFE CYCLE ASSESSMENT

    EPA Science Inventory

    This is a special issue of Journal of Life Cycle Assessment that includes selected papers from the Internatonal Conference and Exhibition on Life Cycle Assessment (InLCA). In April 2000, the EPA, with co-organizer IERE, held the InLCA conferencethat attracted over 265 attendees (...

  8. Maritime vessel obsolescence, life cycle cost and design service life

    NASA Astrophysics Data System (ADS)

    Dinu, O.; Ilie, A. M.

    2015-11-01

    Maritime vessels have long service life and great costs of building, manning, operating, maintaining and repairing throughout their life. Major actions are needed to repair, renovate, sometime built or even replace those scrapped when technology or demand changes determine obsolescence. It is regarded as a concern throughout vessel's entire life cycle and reflects changes in expectation regarding performances in functioning, safety and environmental effects. While service live may differ from physical lives, expectations about physical lives is the main factors that determines design service life. Performance and failure are illustrated conceptually and represented in a simplified form considering the evolution of vessels parameters during its service life. In the proposed methodology an accumulated vessel lifecycle cost is analyzed and obsolescence is characterized from ship's design, performances, maintenance and management parameters point of view. Romanian ports feeding Black Sea are investigated in order to provide comprehensive information on: number and types of vessels, transport capacity and life cycle length. Recommendations are to be made in order to insure a best practice in lifecycle management in order to reduce costs.

  9. The circle of life: A cross-cultural comparison of children's attribution of life-cycle traits.

    PubMed

    Burdett, Emily R R; Barrett, Justin L

    2016-06-01

    Do children attribute mortality and other life-cycle traits to all minded beings? The present study examined whether culture influences young children's ability to conceptualize and differentiate human beings from supernatural beings (such as God) in terms of life-cycle traits. Three-to-5-year-old Israeli and British children were questioned whether their mother, a friend, and God would be subject to various life-cycle processes: Birth, death, ageing, existence/longevity, and parentage. Children did not anthropomorphize but differentiated among human and supernatural beings, attributing life-cycle traits to humans, but not to God. Although 3-year-olds differentiated significantly among agents, 5-year-olds attributed correct life-cycle traits more consistently than younger children. The results also indicated some cross-cultural variation in these attributions. Implications for biological conceptual development are discussed. © 2015 The British Psychological Society.

  10. Kinesthetic Life Cycle of Stars

    NASA Astrophysics Data System (ADS)

    Reinfeld, Erika L.; Hartman, Mark A.

    We present a kinesthetic approach to learning about the life cycle of stars. Using a simplified two-layer model for stellar structure, learners recreate kinesthetically the birth, life, and death of low- and high-mass stars. Examples of how this activity has been used in several settings outside school time provide additional resources for extending student learning about this topic.

  11. THE EPA'S EMERGING FOCUS ON LIFE CYCLE ASSESSMENT

    EPA Science Inventory

    EPA has been actively engaged in LCA research since 1990 to help advance the methodology and application of life cycle thinking in decision making. Across the Agency consideration of the life cycle concept is increasing in the development of policies and programs. A major force i...

  12. 10 CFR 436.42 - Evaluation of Life-Cycle Cost Effectiveness.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Evaluation of Life-Cycle Cost Effectiveness. 436.42... PROGRAMS Agency Procurement of Energy Efficient Products § 436.42 Evaluation of Life-Cycle Cost...) ENERGY STAR qualified and FEMP designated products may be assumed to be life-cycle cost-effective. (b) In...

  13. 10 CFR 436.42 - Evaluation of Life-Cycle Cost Effectiveness.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Evaluation of Life-Cycle Cost Effectiveness. 436.42... PROGRAMS Agency Procurement of Energy Efficient Products § 436.42 Evaluation of Life-Cycle Cost...) ENERGY STAR qualified and FEMP designated products may be assumed to be life-cycle cost-effective. (b) In...

  14. 10 CFR 436.42 - Evaluation of Life-Cycle Cost Effectiveness.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Evaluation of Life-Cycle Cost Effectiveness. 436.42... PROGRAMS Agency Procurement of Energy Efficient Products § 436.42 Evaluation of Life-Cycle Cost...) ENERGY STAR qualified and FEMP designated products may be assumed to be life-cycle cost-effective. (b) In...

  15. 10 CFR 436.42 - Evaluation of Life-Cycle Cost Effectiveness.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Evaluation of Life-Cycle Cost Effectiveness. 436.42... PROGRAMS Agency Procurement of Energy Efficient Products § 436.42 Evaluation of Life-Cycle Cost...) ENERGY STAR qualified and FEMP designated products may be assumed to be life-cycle cost-effective. (b) In...

  16. The search for life on Europa: limiting environmental factors, potential habitats, and Earth analogues.

    PubMed

    Marion, Giles M; Fritsen, Christian H; Eicken, Hajo; Payne, Meredith C

    2003-01-01

    The putative ocean of Europa has focused considerable attention on the potential habitats for life on Europa. By generally clement Earth standards, these Europan habitats are likely to be extreme environments. The objectives of this paper were to examine: (1) the limits for biological activity on Earth with respect to temperature, salinity, acidity, desiccation, radiation, pressure, and time; (2) potential habitats for life on Europa; and (3) Earth analogues and their limitations for Europa. Based on empirical evidence, the limits for biological activity on Earth are: (1) the temperature range is from 253 to 394 K; (2) the salinity range is a(H2O) = 0.6-1.0; (3) the desiccation range is from 60% to 100% relative humidity; (4) the acidity range is from pH 0 to 13; (5) microbes such as Deinococcus are roughly 4,000 times more resistant to ionizing radiation than humans; (6) the range for hydrostatic pressure is from 0 to 1,100 bars; and (7) the maximum time for organisms to survive in the dormant state may be as long as 250 million years. The potential habitats for life on Europa are the ice layer, the brine ocean, and the seafloor environment. The dual stresses of lethal radiation and low temperatures on or near the icy surface of Europa preclude the possibility of biological activity anywhere near the surface. Only at the base of the ice layer could one expect to find the suitable temperatures and liquid water that are necessary for life. An ice layer turnover time of 10 million years is probably rapid enough for preserving in the surface ice layers dormant life forms originating from the ocean. Model simulations demonstrate that hypothetical oceans could exist on Europa that are too cold for biological activity (T < 253 K). These simulations also demonstrate that salinities are high, which would restrict life to extreme halophiles. An acidic ocean (if present) could also potentially limit life. Pressure, per se, is unlikely to directly limit life on Europa. But

  17. NREL: U.S. Life Cycle Inventory Database - Related Links

    Science.gov Websites

    ) information, LCA tools, research institutes utilizing LCA, labeling initiatives and organizations , international LCA initiatives, LCA online forums. Life Cycle Inventory Data Ecoinvent: Swiss Centre for Life Institute for Environmental Research and Education): The American Center for Life Cycle Assessment SETAC

  18. Residential Preferences and Moving Behavior: A Family Life Cycle Analysis.

    ERIC Educational Resources Information Center

    McAuley, William J.; Nutty, Cheri L.

    The relationship of family life cycle changes to housing preferences and residential mobility is examined. Two residential decision-making issues are explored in detail--how family life cycle stages influence what people view as important to their choice of residential setting and what individuals at different family life cycle stages view as the…

  19. 10 CFR 436.42 - Evaluation of Life-Cycle Cost Effectiveness.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the life-cycle cost analysis method in part 436, subpart A, of title 10 of the Code of Federal... 10 Energy 3 2011-01-01 2011-01-01 false Evaluation of Life-Cycle Cost Effectiveness. 436.42... PROGRAMS Agency Procurement of Energy Efficient Products § 436.42 Evaluation of Life-Cycle Cost...

  20. Information system life-cycle and documentation standards, volume 1

    NASA Technical Reports Server (NTRS)

    Callender, E. David; Steinbacher, Jody

    1989-01-01

    The Software Management and Assurance Program (SMAP) Information System Life-Cycle and Documentation Standards Document describes the Version 4 standard information system life-cycle in terms of processes, products, and reviews. The description of the products includes detailed documentation standards. The standards in this document set can be applied to the life-cycle, i.e., to each phase in the system's development, and to the documentation of all NASA information systems. This provides consistency across the agency as well as visibility into the completeness of the information recorded. An information system is software-intensive, but consists of any combination of software, hardware, and operational procedures required to process, store, or transmit data. This document defines a standard life-cycle model and content for associated documentation.

  1. Application of Life Cycle Assessment on Electronic Waste Management: A Review

    NASA Astrophysics Data System (ADS)

    Xue, Mianqiang; Xu, Zhenming

    2017-04-01

    Electronic waste is a rich source of both valuable materials and toxic substances. Management of electronic waste is one of the biggest challenges of current worldwide concern. As an effective and prevailing environmental management tool, life cycle assessment can evaluate the environmental performance of electronic waste management activities. Quite a few scientific literatures reporting life cycle assessment of electronic waste management with significant outcomes have been recently published. This paper reviewed the trends, characteristics, research gaps, and challenges of these studies providing detailed information for practitioners involved in electronic waste management. The results showed that life cycle assessment studies were most carried out in Europe, followed by Asia and North America. The research subject of the studies mainly includes monitors, waste printed circuit boards, mobile phones, computers, printers, batteries, toys, dishwashers, and light-emitting diodes. CML was the most widely used life cycle impact assessment method in life cycle assessment studies on electronic waste management, followed by EI99. Furthermore, 40% of the reviewed studies combined with other environmental tools, including life cycle cost, material flow analysis, multi-criteria decision analysis, emergy analysis, and hazard assessment which came to more comprehensive conclusions from different aspects. The research gaps and challenges including uneven distribution of life cycle assessment studies, life cycle impact assessment methods selection, comparison of the results, and uncertainty of the life cycle assessment studies were examined. Although life cycle assessment of electronic waste management facing challenges, their results will play more and more important role in electronic waste management practices.

  2. Application of Life Cycle Assessment on Electronic Waste Management: A Review.

    PubMed

    Xue, Mianqiang; Xu, Zhenming

    2017-04-01

    Electronic waste is a rich source of both valuable materials and toxic substances. Management of electronic waste is one of the biggest challenges of current worldwide concern. As an effective and prevailing environmental management tool, life cycle assessment can evaluate the environmental performance of electronic waste management activities. Quite a few scientific literatures reporting life cycle assessment of electronic waste management with significant outcomes have been recently published. This paper reviewed the trends, characteristics, research gaps, and challenges of these studies providing detailed information for practitioners involved in electronic waste management. The results showed that life cycle assessment studies were most carried out in Europe, followed by Asia and North America. The research subject of the studies mainly includes monitors, waste printed circuit boards, mobile phones, computers, printers, batteries, toys, dishwashers, and light-emitting diodes. CML was the most widely used life cycle impact assessment method in life cycle assessment studies on electronic waste management, followed by EI99. Furthermore, 40% of the reviewed studies combined with other environmental tools, including life cycle cost, material flow analysis, multi-criteria decision analysis, emergy analysis, and hazard assessment which came to more comprehensive conclusions from different aspects. The research gaps and challenges including uneven distribution of life cycle assessment studies, life cycle impact assessment methods selection, comparison of the results, and uncertainty of the life cycle assessment studies were examined. Although life cycle assessment of electronic waste management facing challenges, their results will play more and more important role in electronic waste management practices.

  3. The observed life cycle of a baroclinic instability

    NASA Technical Reports Server (NTRS)

    Randel, W. J.; Stanford, J. L.

    1985-01-01

    Medium-scale waves (zonal wavenumbers 4-7) frequently dominate Southern Hemisphere summer circulation patterns. Randel and Stanford have studied the dynamics of these features, demonstrating that the medium-scale waves result from baroclinic excitation and exhibit well-defined life cycles. This study details the evolution of the medium-scale waves during a particular life cycle. The specific case chosen exhibits a high degree of zonal symmetry, prompting study based upon zonally averaged diagnostics. An analysis of the medium-scale wave energetics reveals a well-defined life cycle of baroclinic growth, maturity, and barotropic decay. Eliassen-Palm flux diagrams detail the daily wave structure and its interaction with the zonally-averaged flow.

  4. Evaluation of life-cycle air emission factors of freight transportation.

    PubMed

    Facanha, Cristiano; Horvath, Arpad

    2007-10-15

    Life-cycle air emission factors associated with road, rail, and air transportation of freight in the United States are analyzed. All life-cycle phases of vehicles, infrastructure, and fuels are accounted for in a hybrid life-cycle assessment (LCA). It includes not only fuel combustion, but also emissions from vehicle manufacturing, maintenance, and end of life, infrastructure construction, operation, maintenance, and end of life, and petroleum exploration, refining, and fuel distribution. Results indicate that total life-cycle emissions of freight transportation modes are underestimated if only tailpipe emissions are accounted for. In the case of CO2 and NOx, tailpipe emissions underestimate total emissions by up to 38%, depending on the mode. Total life-cycle emissions of CO and SO2 are up to seven times higher than tailpipe emissions. Sensitivity analysis considers the effects of vehicle type, geography, and mode efficiency on the final results. Policy implications of this analysis are also discussed. For example, while it is widely assumed that currently proposed regulations will result in substantial reductions in emissions, we find that this is true for NOx, emissions, because fuel combustion is the main cause, and to a lesser extent for SO2, but not for PM10 emissions, which are significantly affected by the other life-cycle phases.

  5. REPORT ON ACTIVITY OF TASK FORCE 1 IN THE LIFE CYCLE INVENTORY PROGRAMME: DATA REGISTRY - GLOBAL LIFE CYCLE INVENTORY DATA RESOURCES

    EPA Science Inventory

    This paper presents a summary of the findings of a report prepared by Task Force 1 of the UNEP/SETAC Life Cycle Initiative on the available Life Cycle Inventory (LCI) databases around the world. An update of a previous summary prepared in May 2002 by Norris and Notten, the repor...

  6. Future of lignite resources: a life cycle analysis.

    PubMed

    Wang, Qingsong; Liu, Wei; Yuan, Xueliang; Zheng, Xiaoning; Zuo, Jian

    2016-12-01

    Lignite is a low-quality energy source which accounts for 13 % of China's coal reserves. It is imperative to improve the quality of lignite for large-scale utilization. To further explore and analyze the influence of various key processes on the environment and economic costs, a lignite drying and compression technology is evaluated using an integrated approach of life cycle assessment and life cycle costs. Results showed that lignite mining, direct air emissions, and electricity consumption have most significant impacts on the environment. An integrated evaluation of life cycle assessment and life cycle costs showed that the most significant contributor to the environmental impacts and economic costs was the lignite mining process. The impact of transportation and wastewater treatment process on the environment and economic costs was small enough to be ignored. Critical factors were identified for reducing the environmental and economic impacts of lignite drying and compression technology. These findings provide useful inputs for both industrial practice and policy making for exploitation, processing, and utilization of lignite resources.

  7. Progress in Multi-Disciplinary Data Life Cycle Management

    NASA Astrophysics Data System (ADS)

    Jung, C.; Gasthuber, M.; Giesler, A.; Hardt, M.; Meyer, J.; Prabhune, A.; Rigoll, F.; Schwarz, K.; Streit, A.

    2015-12-01

    Modern science is most often driven by data. Improvements in state-of-the-art technologies and methods in many scientific disciplines lead not only to increasing data rates, but also to the need to improve or even completely overhaul their data life cycle management. Communities usually face two kinds of challenges: generic ones like federated authorization and authentication infrastructures and data preservation, and ones that are specific to their community and their respective data life cycle. In practice, the specific requirements often hinder the use of generic tools and methods. The German Helmholtz Association project ’’Large-Scale Data Management and Analysis” (LSDMA) addresses both challenges: its five Data Life Cycle Labs (DLCLs) closely collaborate with communities in joint research and development to optimize the communities data life cycle management, while its Data Services Integration Team (DSIT) provides generic data tools and services. We present most recent developments and results from the DLCLs covering communities ranging from heavy ion physics and photon science to high-throughput microscopy, and from DSIT.

  8. Life-cycle costing: Practical considerations

    NASA Technical Reports Server (NTRS)

    Eisenberger, I.; Lorden, G.

    1977-01-01

    The history and methodology of life-cycle costing are presented and analyzed, contrasting the potential benefits of the technique with the difficulties of its application. Examples and a short survey of the literature are given.

  9. Simplified Life-Cycle Cost Estimation

    NASA Technical Reports Server (NTRS)

    Remer, D. S.; Lorden, G.; Eisenberger, I.

    1983-01-01

    Simple method for life-cycle cost (LCC) estimation avoids pitfalls inherent in formulations requiring separate estimates of inflation and interest rates. Method depends for validity observation that interest and inflation rates closely track each other.

  10. An ideal sealed source life-cycle

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tompkins, Joseph Andrew

    2009-01-01

    system they we have today. This regulation created a new regulatory framework seen as promising at the time. However, now they recognize that, despite the good intentions, the NIJWP/85 has not solved any source disposition problems. The answer to these sealed source disposition problems is to adopt a philosophy to correct these regulatory issues, determine an interim solution, execute that solution until there is a minimal backlog of sources to deal with, and then let the mechanisms they have created solve this problem into the foreseeable future. The primary philosophical tenet of the ideal sealed source life cycle follows. You do not allow the creation (or importation) of any source whose use cannot be justified, which cannot be affordably shipped, or that does not have a well-delinated and affordable disposition pathway. The path forward dictates that we fix the problem by embracing the Ideal Source Life cycle. In figure 1, we can see some of the elements of the ideal source life cycle. The life cycle is broken down into four portions, manufacture, use, consolidation, and disposition. These four arbitrary elements allow them to focus on the ideal life cycle phases that every source should go through between manufacture and final disposition. As we examine the various phases of the sealed source life cycle, they pick specific examples and explore the adoption of the ideal life cycle model.« less

  11. Ecology and Life Cycle Patterns of Echinococcus Species.

    PubMed

    Romig, T; Deplazes, P; Jenkins, D; Giraudoux, P; Massolo, A; Craig, P S; Wassermann, M; Takahashi, K; de la Rue, M

    2017-01-01

    The genus Echinococcus is composed of eight generally recognized species and one genotypic cluster (Echinococcus canadensis cluster) that may in future be resolved into one to three species. For each species, we review existing information on transmission routes and life cycles in different geographical contexts and - where available - include basic biological information of parasites and hosts (e.g., susceptibility of host species). While some Echinococcus spp. are transmitted in life cycles that involve predominantly domestic animals (e.g., dog - livestock cycles), others are wildlife parasites that do or do not interact with domestic transmission. In many cases, life cycle patterns of the same parasite species differ according to geography. Simple life cycles contrast with transmission patterns that are highly complex, involving multihost systems that may include both domestic and wild mammals. Wildlife transmission may be primary or secondary, i.e., resulting from spillovers from domestic animals. For most of the species and regions, existing information does not yet permit a conclusive description of transmission systems. Such data, however, would be highly relevant, e.g., for anticipation of geographical changes of the presence and frequency of these parasites in a warming world, or for initiating evidence-based control strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Life cycle assessment part 2: current impact assessment practice.

    PubMed

    Pennington, D W; Potting, J; Finnveden, G; Lindeijer, E; Jolliet, O; Rydberg, T; Rebitzer, G

    2004-07-01

    Providing our society with goods and services contributes to a wide range of environmental impacts. Waste generation, emissions and the consumption of resources occur at many stages in a product's life cycle-from raw material extraction, energy acquisition, production and manufacturing, use, reuse, recycling, through to ultimate disposal. These all contribute to impacts such as climate change, stratospheric ozone depletion, photooxidant formation (smog), eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources and noise-among others. The need exists to address these product-related contributions more holistically and in an integrated manner, providing complimentary insights to those of regulatory/process-oriented methodologies. A previous article (Part 1, Rebitzer et al., 2004) outlined how to define and model a product's life cycle in current practice, as well as the methods and tools that are available for compiling the associated waste, emissions and resource consumption data into a life cycle inventory. This article highlights how practitioners and researchers from many domains have come together to provide indicators for the different impacts attributable to products in the life cycle impact assessment (LCIA) phase of life cycle assessment (LCA).

  13. Life Cycle Energy Analysis of Reclaimed Water Reuse Projects in Beijing.

    PubMed

    Fan, Yupeng; Guo, Erhui; Zhai, Yuanzheng; Chang, Andrew C; Qiao, Qi; Kang, Peng

    2018-01-01

      To illustrate the benefits of water reuse project, the process-based life cycle analysis (LCA) could be combined with input-output LCA to evaluate the water reuse project. Energy is the only evaluation parameter used in this study. Life cycle assessment of all energy inputs (LCEA) is completed mainly by the life cycle inventory (LCI), taking into account the full life cycle including the construction, the operation, and the demolition phase of the project. Assessment of benefit from water reuse during the life cycle should focus on wastewater discharge reduction and water-saving benefits. The results of LCEA of Beijing water reuse project built in 2014 in a comprehensive way shows that the benefits obtained from the reclaimed water reuse far exceed the life cycle energy consumption. In this paper, the authors apply the LCEA model to estimate the benefits of reclaimed water reuse projects quantitatively.

  14. Life cycle and nano-products: end-of-life assessment

    NASA Astrophysics Data System (ADS)

    Asmatulu, Eylem; Twomey, Janet; Overcash, Michael

    2012-03-01

    Understanding environmental impacts of nanomaterials necessitates analyzing the life cycle profile. The initial emphasis of nanomaterial life cycle studies has been on the environmental and health effects of nanoproducts during the production and usage stages. Analyzing the end-of-life (eol) stage of nanomaterials is also critical because significant impacts or benefits for the environment may arise at that particular stage. In this article, the Woodrow Wilson Center's Project on Emerging Nanotechnologies (PEN) Consumer Products Inventory (CPI) model was used, which contains a relatively large and complete nanoproduct list (1,014) as of 2010. The consumer products have wide range of applications, such as clothing, sports goods, personal care products, medicine, as well as contributing to faster cars and planes, more powerful computers and satellites, better micro and nanochips, and long-lasting batteries. In order to understand the eol cycle concept, we allocated 1,014 nanoproducts into the nine end-of-life categories (e.g., recyclability, ingestion, absorption by skin/public sewer, public sewer, burning/landfill, landfill, air release, air release/public sewer, and other) based on probable final destinations of the nanoproducts. This article highlights the results of this preliminary assessment of end-of-life stage of nanoproducts. The largest potential eol fate was found to be recyclability, however little literature appears to have evolved around nanoproduct recycling. At lower frequency is dermal and ingestion human uptake and then landfill. Release to water and air are much lower potential eol fates for current nanoproducts. In addition, an analysis of nano-product categories with the largest number of products listed indicated that clothes, followed by dermal-related products and then sports equipment were the most represented in the PEN CPI (http://www.nanotechproject.org/inventories/consumer/browse/categories/, 2010).

  15. Shortening tobacco life cycle accelerates functional gene identification in genomic research.

    PubMed

    Ning, G; Xiao, X; Lv, H; Li, X; Zuo, Y; Bao, M

    2012-11-01

    Definitive allocation of function requires the introduction of genetic mutations and analysis of their phenotypic consequences. Novel, rapid and convenient techniques or materials are very important and useful to accelerate gene identification in functional genomics research. Here, over-expression of PmFT (Prunus mume), a novel FT orthologue, and PtFT (Populus tremula) lead to shortening of the tobacco life cycle. A series of novel short life cycle stable tobacco lines (30-50 days) were developed through repeated self-crossing selection breeding. Based on the second transformation via a gusA reporter gene, the promoter from BpFULL1 in silver birch (Betula pendula) and the gene (CPC) from Arabidopsis thaliana were effectively tested using short life cycle tobacco lines. Comparative analysis among wild type, short life cycle tobacco and Arabidopsis transformation system verified that it is optional to accelerate functional gene studies by shortening host plant material life cycle, at least in these short life cycle tobacco lines. The results verified that the novel short life cycle transgenic tobacco lines not only combine the advantages of economic nursery requirements and a simple transformation system, but also provide a robust, effective and stable host system to accelerate gene analysis. Thus, shortening tobacco life cycle strategy is feasible to accelerate heterologous or homologous functional gene identification in genomic research. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  16. Ecology of bonytail and razorback sucker and the role of off-channel habitats in their recovery

    USGS Publications Warehouse

    Mueller, Gordon A.

    2006-01-01

    This report presents new findings, updates existing information, and describes what may well represent the only practical approach to these species’ conservation and recovery. Chapter 1 provides an overview of the Colorado River system from its origin to the Gulf of California and includes a description of propagation and stocking programs which have not been described elsewhere. The report also updates what is known or suspected on the life history and ecology of these two endangered fishes. Chapter 2 describes the successful recruitment of both species at an oxbow pond on the Cibola National Wildlife Refuge in Arizona, discusses factors that contribute to completion of the life cycle of both fishes, and provides recommendations for future management of the impoundment. Chapter 3 provides historical evidence that oxbow habitats were formed historically in years of high runoff and the importance of these habitats for survival and evolution of native fishes. It also summarizes key features of habitats that can serve as sanctuaries that enhance early survival of the endangered fishes and allow the fish to complete their entire life cycles.

  17. USING LIFE CYCLE ASSESSMENT TOOLS FOR INTEGRATED PRODUCT POLICY

    EPA Science Inventory

    The European Union's new Integrated Product Policy directs governments and companies to consider the entire product life cycle, from cradle to grave, in their environmental decision-making process. A life-cycle based approach is intended to lead toward true environmental improvem...

  18. Crash Attenuator Data Collection and Life Cycle Tool Development

    DOT National Transportation Integrated Search

    2014-06-14

    This research study was aimed at data collection and development of a decision support tool for life cycle cost assessment of crash attenuators. Assessing arrenuator life cycle costs based on in-place expected costs and not just the initial cost enha...

  19. Robotic Technologies for Surveying Habitats and Seeking Evidence of Life: Results from the 2004 Field Experiments of the "Life in the Atacama" Project

    NASA Technical Reports Server (NTRS)

    Wettergreen, D.; Cabrol, N.; Whittaker, W.; Diaz, G. Chong; Calderon, F.; Heys, S.; Jonak, D.; Lueders, A.; Moersch, J.; Pane, D.

    2005-01-01

    The Chilean Atacama Desert is the most arid region on Earth and in several ways analogous to Mars. Evidence suggests that the interior of the Atacama is lifeless, yet where the desert meets the Pacific coastal range dessication-tolerant microorganisms are known to exist. The gradient of biodiversity and habitats in the Atacama's subregions remain unexplored and are the focus of the Life in the Atacama project. Our field investigation attempts to bring further scientific understanding of the Atacama as a habitat for life through the creation of robotic astrobiology. This involves capabilities for autonomously traversing hundreds of kilometers while deploying sensors to survey the varying geologic and biologic properties of the environment, Fig. 1. Our goal is to make genuine discoveries about the limits of life on Earth and to generate knowledge about life in extreme environments that can be applied to future planetary missions. Through these experiments we also hope to develop and practice the methods by which a rover might best be employed to survey desert terrain in search of the habitats in which life can survive, or may have in the past.

  20. An optimised multi-host trematode life cycle: fishery discards enhance trophic parasite transmission to scavenging birds.

    PubMed

    Born-Torrijos, Ana; Poulin, Robert; Pérez-Del-Olmo, Ana; Culurgioni, Jacopo; Raga, Juan Antonio; Holzer, Astrid Sibylle

    2016-10-01

    Overlapping distributions of hosts and parasites are critical for successful completion of multi-host parasite life cycles and even small environmental changes can impact on the parasite's presence in a host or habitat. The generalist Cardiocephaloides longicollis was used as a model for multi-host trematode life cycles in marine habitats. This parasite was studied to quantify parasite dispersion and transmission dynamics, effects of biological changes and anthropogenic impacts on life cycle completion. We compiled the largest host dataset to date, by analysing 3351 molluscs (24 species), 2108 fish (25 species) and 154 birds (17 species) and analysed the resultant data based on a number of statistical models. We uncovered extremely low host specificity at the second intermediate host level and a preference of the free-swimming larvae for predominantly demersal but also benthic fish. The accumulation of encysted larvae in the brain with increasing fish size demonstrates that parasite numbers level off in fish larger than 140mm, consistent with parasite-induced mortality at these levels. The highest infection rates were detected in host species and sizes representing the largest fraction of Mediterranean fishery discards (up to 67% of the total catch), which are frequently consumed by seabirds. Significantly higher parasite densities were found in areas with extensive fishing activity than in those with medium and low activity, and in fish from shallow lagoons than in fish from other coastal areas. For the first time, C. longicollis was also detected in farmed fish in netpens. Fishing generally drives declines in parasite abundance, however, our study suggests an enhanced transmission of generalist parasites such as C. longicollis, an effect that is further amplified by the parasite's efficient host-finding mechanisms and its alteration of fish host behaviour by larvae encysted in the brain. The anthropogenic impact on the distribution of trophically

  1. LIFE CYCLE ASSESSMENT FOR PC BLEND 2 AIRCRAFT RADOME DEPAINTER

    EPA Science Inventory

    This report describes the life cycle assessment on a potential replacement solvent blend for aircraft radome depainting at the Oklahoma City Air Logistics Center at Tinker Air Force Base. The life cycle assessment is composed of three separate but interrelated components: life cy...

  2. Habitats and Surface Construction Technology and Development Roadmap

    NASA Technical Reports Server (NTRS)

    Cohen, Marc; Kennedy, Kriss J.

    1997-01-01

    The vision of the technology and development teams at NASA Ames and Johnson Research Centers is to provide the capability for automated delivery and emplacement of habitats and surface facilities. The benefits of the program are as follows: Composites and Inflatables: 30-50% (goal) lighter than Al Hard Structures; Capability for Increased Habitable Volume, Launch Efficiency; Long Term Growth Potential; and Supports initiation of commercial and industrial expansion. Key Habitats and Surface Construction (H&SC) technology issues are: Habitat Shell Structural Materials; Seals and Mechanisms; Construction and Assembly: Automated Pro-Deploy Construction Systems; ISRU Soil/Construction Equipment: Lightweight and Lower Power Needs; Radiation Protection (Health and Human Performance Tech.); Life Support System (Regenerative Life Support System Tech.); Human Physiology of Long Duration Space Flight (Health and Human Performance Tech.); and Human Psychology of Long Duration Space Flight (Health and Human Performance Tech.) What is being done regarding these issues?: Use of composite materials for X-38 CRV, RLV, etc.; TransHAB inflatable habitat design/development; Japanese corporations working on ISRU-derived construction processes. What needs to be done for the 2004 Go Decision?: Characterize Mars Environmental Conditions: Civil Engineering, Material Durability, etc.; Determine Credibility of Inflatable Structures for Human Habitation; and Determine Seal Technology for Mechanisms and Hatches, Life Cycle, and Durability. An overview encompassing all of the issues above is presented.

  3. LIFE CYCLE IMPACT ASSESSMENT AN INTRODUCTION AND INTERNATIONAL UPDATE

    EPA Science Inventory

    Research within the field of Life Cycle Impact Assessment (LCIA) has greatly improved since the work of Heijungs and Guinee in 1992. Within the UNEP / SETAC Life Cycle Initiative an effort is underway to provide recommendations about the direction of research and selection of LC...

  4. Test of US Federal Life Cycle Inventory Data Interoperability

    EPA Science Inventory

    Life cycle assessment practitioners must gather data from a variety of sources. For modeling activities in the US, practitioners may wish to use life cycle inventory data from public databases and libraries provided by US government entities. An exercise was conducted to test if ...

  5. Life cycle strategies of copepods in coastal upwelling zones

    NASA Astrophysics Data System (ADS)

    Peterson, W.

    1998-06-01

    Life cycles of copepods of coastal upwelling zones are of the multigenerational type—as many as 10 or more generations may be produced each year, depending upon water temperature, food concentration and length of the upwelling season. Abundant food resources and moderate temperature convey advantages to those copepods living in coastal upwelling zones, however, there is a clear disadvantage in that coastal upwelling zones are highly advective environments. Typically, water circulation patterns are such that surface waters are carried offshore, deeper waters carried onshore and most of the water column over the continental shelf is moving equatorward. The challenge to copepod species that inhabit upwelling systems is life cycle closure—how do eggs, nauplii, juveniles and adults avoid being swept out of these ecosystems in the face of persistent transport out of the system? In this review, I first list the species which dominate coastal upwelling ecosystems then discuss three variations on the multigenerational life cycle scheme that are observed in upwelling systems. The latter part of the review is devoted to discussion of how individuals are retained in the productive continental shelf waters within coastal upwelling ecosystems. The suggestion is made that the only copepod species that successfully achieve life cycle closure in such systems are those that are preadapted to upwelling circulation patterns. Our quantitative understanding of the relative importance of physical factors (such as advection) and biological factors (birth, growth, and mortality) on life cycle strategies and population dynamics is quite rudimentary. It would help our understanding if there were more field studies and more computer modeling studies that focused on seasonal cycles of abundance, development times and vertical distribution of life cycle stages, and measurements of water circulation patterns.

  6. LIFE-CYCLE IMPACT ASSESSMENT DEMONSTRATION FOR THE BGU-24

    EPA Science Inventory

    The primary goal of this project was to develop and demonstrate a life-cycle impact assessment (LCIA) approach using existing life-cycle inventory (LCI) data on one of the propellants, energetics, and pyrotechnic (PEP) materials of interest to the U.S. Department of Defense (DoD)...

  7. LIFE-CYCLE IMPACT ASSESSMENT DEMONSTRATION FOR THE GBU-24

    EPA Science Inventory

    The primary goal of this project was to develop and demonstrate a life-cycle impact assessment (LCIA) approach using existing life-cycle inventory (LCI) data on one of the propellants, energetics, and pyro-technic (PEP) materials of interest to the U.S. Department of Defense (DoD...

  8. A Game to Teach the Life Cycles of Fungi

    ERIC Educational Resources Information Center

    Blum, Abraham

    1976-01-01

    Presented is a biological game utilized to teach fungi life cycles to secondary biology students. The game is designed to overcome difficulties of correlating schematic drawings with images seen through the microscope, correlating life cycles of fungi and host, and understanding cyclic development of fungi. (SL)

  9. LCACCESS: A GLOBAL DIRECTORY OF LIFE CYCLE ASSESSMENT RESOURCES

    EPA Science Inventory

    LCAccess is an EPA-sponsored website intended to promote the use of Life Cycle Assessment (LCA) in business decision-making by faciliatating access to data sources that are useful in developing a life cycle inventory (LCI). While LCAccess does not itself contain data, it is a sea...

  10. Waste-to-energy: A review of life cycle assessment and its extension methods.

    PubMed

    Zhou, Zhaozhi; Tang, Yuanjun; Chi, Yong; Ni, Mingjiang; Buekens, Alfons

    2018-01-01

    This article proposes a comprehensive review of evaluation tools based on life cycle thinking, as applied to waste-to-energy. Habitually, life cycle assessment is adopted to assess environmental burdens associated with waste-to-energy initiatives. Based on this framework, several extension methods have been developed to focus on specific aspects: Exergetic life cycle assessment for reducing resource depletion, life cycle costing for evaluating its economic burden, and social life cycle assessment for recording its social impacts. Additionally, the environment-energy-economy model integrates both life cycle assessment and life cycle costing methods and judges simultaneously these three features for sustainable waste-to-energy conversion. Life cycle assessment is sufficiently developed on waste-to-energy with concrete data inventory and sensitivity analysis, although the data and model uncertainty are unavoidable. Compared with life cycle assessment, only a few evaluations are conducted to waste-to-energy techniques by using extension methods and its methodology and application need to be further developed. Finally, this article succinctly summarises some recommendations for further research.

  11. Vacant habitats in the Universe.

    PubMed

    Cockell, Charles S

    2011-02-01

    The search for life on other planets usually makes the assumption that where there is a habitat, it will contain life. On the present-day Earth, uninhabited habitats (or vacant habitats) are rare, but might occur, for example, in subsurface oils or impact craters that have been thermally sterilized in the past. Beyond Earth, vacant habitats might similarly exist on inhabited planets or on uninhabited planets, for example on a habitable planet where life never originated. The hypothesis that vacant habitats are abundant in the Universe is testable by studying other planets. In this review, I discuss how the study of vacant habitats might ultimately inform an understanding of how life has influenced geochemical conditions on Earth. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. The evolution of life cycle complexity in aphids: Ecological optimization or historical constraint?

    PubMed

    Hardy, Nate B; Peterson, Daniel A; von Dohlen, Carol D

    2015-06-01

    For decades, biologists have debated why many parasites have obligate multihost life cycles. Here, we use comparative phylogenetic analyses of aphids to evaluate the roles of ecological optimization and historical constraint in the evolution of life cycle complexity. If life cycle complexity is adaptive, it should be evolutionarily labile, that is, change in response to selection. We provide evidence that this is true in some aphids (aphidines), but not others (nonaphidines)-groups that differ in the intensity of their relationships with primary hosts. Next, we test specific mechanisms by which life cycle complexity could be adaptive or a constraint. We find that among aphidines there is a strong association between complex life cycles and polyphagy but only a weak correlation between life cycle complexity and reproductive mode. In contrast, among nonaphidines the relationship between life cycle complexity and host breadth is weak but the association between complex life cycles and sexual reproduction is strong. Thus, although the adaptiveness of life cycle complexity appears to be lineage specific, across aphids, life cycle evolution appears to be tightly linked with the evolution of other important natural history traits. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  13. 10 CFR 434.607 - Life cycle cost analysis criteria.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Life cycle cost analysis criteria. 434.607 Section 434.607 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Compliance Alternative § 434.607 Life cycle cost...

  14. 10 CFR 434.607 - Life cycle cost analysis criteria.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Life cycle cost analysis criteria. 434.607 Section 434.607 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Compliance Alternative § 434.607 Life cycle cost...

  15. 10 CFR 434.607 - Life cycle cost analysis criteria.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Life cycle cost analysis criteria. 434.607 Section 434.607 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Compliance Alternative § 434.607 Life cycle cost...

  16. Early-Life Origins of Life-Cycle Well-Being: Research and Policy Implications

    ERIC Educational Resources Information Center

    Currie, Janet; Rossin-Slater, Maya

    2015-01-01

    Mounting evidence across different disciplines suggests that early-life conditions can have consequences on individual outcomes throughout the life cycle. Relative to other developed countries, the United States fares poorly on standard indicators of early-life health, and this disadvantage may have profound consequences not only for population…

  17. Sourcing Life Cycle Inventory Data

    EPA Science Inventory

    The collection and validation of quality lifecycle inventory (LCI) data can be the most difficult and time-consuming aspect of developing a life cycle assessment (LCA). Large amounts of process and production data are needed to complete the LCI. For many studies, the LCA analyst ...

  18. Improving Life-Cycle Cost Management of Spacecraft Missions

    NASA Technical Reports Server (NTRS)

    Clardy, Dennon

    2010-01-01

    This presentation will explore the results of a recent NASA Life-Cycle Cost study and how project managers can use the findings and recommendations to improve planning and coordination early in the formulation cycle and avoid common pitfalls resulting in cost overruns. The typical NASA space science mission will exceed both the initial estimated and the confirmed life-cycle costs by the end of the mission. In a fixed-budget environment, these overruns translate to delays in starting or launching future missions, or in the worst case can lead to cancelled missions. Some of these overruns are due to issues outside the control of the project; others are due to the unpredictable problems (unknown unknowns) that can affect any development project. However, a recent study of life-cycle cost growth by the Discovery and New Frontiers Program Office identified a number of areas that are within the scope of project management to address. The study also found that the majority of the underlying causes for cost overruns are embedded in the project approach during the formulation and early design phases, but the actual impacts typically are not experienced until late in the project life cycle. Thus, project management focus in key areas such as integrated schedule development, management structure and contractor communications processes, heritage and technology assumptions, and operations planning, can be used to validate initial cost assumptions and set in place management processes to avoid the common pitfalls resulting in cost overruns.

  19. Comparative Life Cycle Assessment between Warm SMA and Conventional SMA

    DOT National Transportation Integrated Search

    2011-09-01

    This report presents the comparative life cycle assessment (LCA) between warm stone mastic asphalt (SMA) and conventional : SMA. Specifically, the study evaluated and compared the life cycle environmental and economic performances of two mixtures: a ...

  20. Life Cycle Impact Assessment (videotape)

    EPA Science Inventory

    Originally developed for the US EPA Regions, this presentation is available to the general public via the internet. The presentation focuses on the basics of Life Cycle Impact Assessment (LCIA) including the ISO 14040 series framework and a quick overview of each of the steps wi...

  1. Spatially-explicit life cycle assessment of sun-to-wheels transportation pathways in the U.S.

    PubMed

    Geyer, Roland; Stoms, David; Kallaos, James

    2013-01-15

    Growth in biofuel production, which is meant to reduce greenhouse gas (GHG) emissions and fossil energy demand, is increasingly seen as a threat to food supply and natural habitats. Using photovoltaics (PV) to directly convert solar radiation into electricity for battery electric vehicles (BEVs) is an alternative to photosynthesis, which suffers from a very low energy conversion efficiency. Assessments need to be spatially explicit, since solar insolation and crop yields vary widely between locations. This paper therefore compares direct land use, life cycle GHG emissions and fossil fuel requirements of five different sun-to-wheels conversion pathways for every county in the contiguous U.S.: Ethanol from corn or switchgrass for internal combustion vehicles (ICVs), electricity from corn or switchgrass for BEVs, and PV electricity for BEVs. Even the most land-use efficient biomass-based pathway (i.e., switchgrass bioelectricity in U.S. counties with hypothetical crop yields of over 24 tonnes/ha) requires 29 times more land than the PV-based alternative in the same locations. PV BEV systems also have the lowest life cycle GHG emissions throughout the U.S. and the lowest fossil fuel inputs, except for locations with hypothetical switchgrass yields of 16 or more tonnes/ha. Including indirect land use effects further strengthens the case for PV.

  2. Transport of Passive Tracers in Baroclinic Wave Life Cycles

    NASA Technical Reports Server (NTRS)

    Stone, Elizabeth M.; Randel, William J.; Stanford, John L.

    1999-01-01

    The transport of passive tracers in idealized baroclinic wave life cycles is studied using output from the National Center for Atmospheric Research Community Climate Model (CCM2). Two life cycles, LCn and LCs, are simulated, starting with baroclinically unstable initial conditions similar to those used by Thorncroft et al. in their study of two life cycle paradigms. The two life cycles LCn and LCs have different initial horizontal wind shear structures that result in distinctive nonlinear development. In terms of potential vorticity-potential temperature (PV-theta) diagnostics, the LCn case is characterized by thinning troughs that are advected anti-cyclonically and equatorward, while the LCs case has broadening troughs that wrap up cyclonically and poleward. Four idealized passive tracers are included in the model to be advected by the semi-Lagrangian transport scheme of the CCM2, and their evolutions are investigated throughout the life cycles. Tracer budgets are analyzed in terms of the transformed Eulerian mean constituent transport formalism in pressure coordinates and also in isentropic coordinates. Results for both LCn and LCs show transport that is downgradient with respect to the background structure of the tracer field, but with a characteristic spatial structure that maximizes in the middle to high latitudes. For the idealized tropospheric tracers in this study, this represents a net upward and poleward transport that enhances concentrations at high latitudes. These results vary little with the initial distribution of the constituent field. The time tendency of the tracer is influenced most strongly by the eddy flux term. with the largest transport occurring during the nonlinear growth stage of the life cycle. The authors also study the transport of a lower-stratospheric tracer, to examine stratosphere-troposphere exchange for baroclinic waves.

  3. KOH concentration effect on the cycle life of nickel-hydrogen cells

    NASA Technical Reports Server (NTRS)

    Lim, H. S.; Verzwyvelt, S. A.

    1985-01-01

    Effects of KOH concentration on the cycle life of a sintered-type nickel electrode were studied in a boiler plate nickel-hydrogen cell at 23 C using an accelerated 45-min cycle regime at 80 percent depth of discharge. The cycle life improved greatly as the KOH concentration decreased, although the initial capacity of the cell decreased slightly. The cycle life improved by a factor of two or more when the KOH concentration was reduced from 36 to 31 percent and by a similar factor from reductions of 31 to 26 percent. For many applications, this life improvement may outweigh the initial capacity decrease.

  4. Life cycle assessment of electronic waste treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hong, Jinglan, E-mail: hongjing@sdu.edu.cn; Shandong University Climate Change and Health Center, Public Health School, Shandong University, Jinan 250012; Shi, Wenxiao

    Highlights: • Life cycle assessment of electronic waste recycling is quantified. • Key factors for reducing the overall environmental impact are indentified. • End-life disposal processes provide significant environmental benefits. • Efficiently reduce the improper disposal amount of e-waste is highly needed. • E-waste incineration can generate significant environmental burden. - Abstract: Life cycle assessment was conducted to estimate the environmental impact of electronic waste (e-waste) treatment. E-waste recycling with an end-life disposal scenario is environmentally beneficial because of the low environmental burden generated from human toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, and marine ecotoxicity categories. Landfill and incineration technologies havemore » a lower and higher environmental burden than the e-waste recycling with an end-life disposal scenario, respectively. The key factors in reducing the overall environmental impact of e-waste recycling are optimizing energy consumption efficiency, reducing wastewater and solid waste effluent, increasing proper e-waste treatment amount, avoiding e-waste disposal to landfill and incineration sites, and clearly defining the duties of all stakeholders (e.g., manufacturers, retailers, recycling companies, and consumers)« less

  5. Optimizing conceptual aircraft designs for minimum life cycle cost

    NASA Technical Reports Server (NTRS)

    Johnson, Vicki S.

    1989-01-01

    A life cycle cost (LCC) module has been added to the FLight Optimization System (FLOPS), allowing the additional optimization variables of life cycle cost, direct operating cost, and acquisition cost. Extensive use of the methodology on short-, medium-, and medium-to-long range aircraft has demonstrated that the system works well. Results from the study show that optimization parameter has a definite effect on the aircraft, and that optimizing an aircraft for minimum LCC results in a different airplane than when optimizing for minimum take-off gross weight (TOGW), fuel burned, direct operation cost (DOC), or acquisition cost. Additionally, the economic assumptions can have a strong impact on the configurations optimized for minimum LCC or DOC. Also, results show that advanced technology can be worthwhile, even if it results in higher manufacturing and operating costs. Examining the number of engines a configuration should have demonstrated a real payoff of including life cycle cost in the conceptual design process: the minimum TOGW of fuel aircraft did not always have the lowest life cycle cost when considering the number of engines.

  6. Extreme habitats as refuge from parasite infections? Evidence from an extremophile fish

    NASA Astrophysics Data System (ADS)

    Tobler, Michael; Schlupp, Ingo; García de León, Francisco J.; Glaubrecht, Matthias; Plath, Martin

    2007-05-01

    Living in extreme habitats typically requires costly adaptations of any organism tolerating these conditions, but very little is known about potential benefits that trade off these costs. We suggest that extreme habitats may function as refuge from parasite infections, since parasites can become locally extinct either directly, through selection by an extreme environmental parameter on free-living parasite stages, or indirectly, through selection on other host species involved in its life cycle. We tested this hypothesis in a small freshwater fish, the Atlantic molly ( Poecilia mexicana) that inhabits normal freshwaters as well as extreme habitats containing high concentrations of toxic hydrogen sulfide. Populations from such extreme habitats are significantly less parasitized by the trematode Uvulifer sp. than a population from a non-sulfidic habitat. We suggest that reduced parasite prevalence may be a benefit of living in sulfidic habitats.

  7. Life Cycle Reversal in Aurelia sp.1 (Cnidaria, Scyphozoa)

    PubMed Central

    He, Jinru; Zheng, Lianming; Zhang, Wenjing; Lin, Yuanshao

    2015-01-01

    The genus Aurelia is one of the major contributors to jellyfish blooms in coastal waters, possibly due in part to hydroclimatic and anthropogenic causes, as well as their highly adaptive reproductive traits. Despite the wide plasticity of cnidarian life cycles, especially those recognized in certain Hydroza species, the known modifications of Aurelia life history were mostly restricted to its polyp stage. In this study, we document the formation of polyps directly from the ectoderm of degenerating juvenile medusae, cell masses from medusa tissue fragments, and subumbrella of living medusae. This is the first evidence for back-transformation of sexually mature medusae into polyps in Aurelia sp.1. The resulting reconstruction of the schematic life cycle of Aurelia reveals the underestimated potential of life cycle reversal in scyphozoan medusae, with possible implications for biological and ecological studies. PMID:26690755

  8. Animal Life Cycles. Animal Life in Action[TM]. Schlessinger Science Library. [Videotape].

    ERIC Educational Resources Information Center

    2000

    This 23-minute videotape for grades 5-8, presents the myriad of animal life that exists on the planet. Students can view and perform experiments and investigations that help explain animal traits and habits. The stages of life that animals pass through--birth, growth, maturation, reproduction, and death--make up the life cycle. Students learn…

  9. The embedded software life cycle - An expanded view

    NASA Technical Reports Server (NTRS)

    Larman, Brian T.; Loesh, Robert E.

    1989-01-01

    Six common issues that are encountered in the development of software for embedded computer systems are discussed from the perspective of their interrelationships with the development process and/or the system itself. Particular attention is given to concurrent hardware/software development, prototyping, the inaccessibility of the operational system, fault tolerance, the long life cycle, and inheritance. It is noted that the life cycle for embedded software must include elements beyond simply the specification and implementation of the target software.

  10. Waste management through life cycle assessment of products

    NASA Astrophysics Data System (ADS)

    Borodin, Yu V.; Aliferova, T. E.; Ncube, A.

    2015-04-01

    The rapid growth of a population in a country can contribute to high production of waste. Municipal waste and industrial waste can bring unhealthy and unpleasant environment or even diseases to human beings if the wastes are not managed properly.With increasing concerns over waste and the need for ‘greener’ products, it is necessary to carry out Life Cycle Assessments of products and this will help manufacturers take the first steps towards greener designs by assessing their product's carbon output. Life Cycle Assessment (LCA) is a process to evaluate the environmental burdens associated with a product, process or activity by identifying and quantifying energy and materials used and wastes released to the environment, and to assess the impact of those energy and material used and released to the environment. The aim of the study was to use a life cycle assessment approach to determine which waste disposal options that will substantially reduce the environmental burdens posed by the Polyethylene Terephthalate (PET) bottle. Several important observations can be made. 1) Recycling of the PET bottle waste can significantly reduce the energy required across the life cycle because the high energy inputs needed to process the requisite virgin materials greatly exceeds the energy needs of the recycling process steps. 2) Greenhouse gases can be reduced by opting for recycling instead of landfilling and incineration. 3) Quantity of waste emissions released from different disposal options was identified. 4) Recycling is the environmentally preferable disposal method for the PET bottle. Industry can use the tools and data in this study to evaluate the health, environmental, and energy implications of the PET bottle. LCA intends to aid decision-makers in this respect, provided that the scientific underpinning is available. Strategic incentives for product development and life cycle management can then be developed.

  11. Development of computer software for pavement life cycle cost analysis.

    DOT National Transportation Integrated Search

    1988-01-01

    The life cycle cost analysis program (LCCA) is designed to automate and standardize life cycle costing in Virginia. It allows the user to input information necessary for the analysis, and it then completes the calculations and produces a printed copy...

  12. EVALUATING THE GREENNESS OF IONIC LIQUIDS VIA LIFE CYCLE ASSESSMENT

    EPA Science Inventory

    Ionic Liquids have been suggested as "greener" replacements to traditional solvents. However, the environmental impacts of the life cycle phases have not been studied. Such a "cradle to gate" Life Cycle Assessment (LCA) for comparing the environmental impact of various solvents...

  13. Life stage and species identity affect whether habitat subsidies enhance or simply redistribute consumer biomass.

    PubMed

    Keller, Danielle A; Gittman, Rachel K; Bouchillon, Rachel K; Fodrie, F Joel

    2017-10-01

    Quantifying the response of mobile consumers to changes in habitat availability is essential for determining the degree to which population-level productivity is habitat limited rather than regulated by other, potentially density-independent factors. Over landscape scales, this can be explored by monitoring changes in density and foraging as habitat availability varies. As habitat availability increases, densities may: (1) decrease (unit-area production decreases; weak habitat limitation); (2) remain stable (unit-area production remains stable; habitat limitation) or (3) increase (unit-area production increases; strong habitat limitation). We tested the response of mobile estuarine consumers over 5 months to changes in habitat availability in situ by comparing densities and feeding rates on artificial reefs that were or were not adjacent to neighbouring artificial reefs or nearby natural reefs. Using either constructed or natural reefs to manipulate habitat availability, we documented threefold density decreases among juvenile stone crabs as habitat increased (i.e. weak habitat imitation). However, for adult stone crabs, density remained stable across treatments, demonstrating that habitat limitation presents a bottleneck in this species' later life history. Oyster toadfish densities also did not change with increasing habitat availability (i.e. habitat limitation), but densities of other cryptic fishes decreased as habitat availability increased (i.e. weak limitation). Feeding and abundance data suggested that some mobile fishes experience habitat limitation, or, potentially in one case, strong limitation across our habitat manipulations. These findings of significant, community-level habitat limitation provide insight into how global declines in structurally complex estuarine habitats may have reduced the fishery production of coastal ecosystems. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  14. Menopause: A Life Cycle Transition.

    ERIC Educational Resources Information Center

    Evarts, Barbara Kess; Baldwin, Cynthia

    1998-01-01

    Family therapists need to address the issue of menopause proactively to be of benefit to couples and families during this transitional period in the family life cycle. Physical, psychological, and psychosocial factors affecting the menopausal woman and her family, and ways to address these issues in counseling are discussed. (Author/EMK)

  15. Life cycle cost based program decisions

    NASA Technical Reports Server (NTRS)

    Dick, James S.

    1991-01-01

    The following subject areas are covered: background (space propulsion facility assessment team final report); changes (Advanced Launch System, National Aerospace Plane, and space exploration initiative); life cycle cost analysis rationale; and recommendation to panel.

  16. 10 CFR 435.306 - Selecting a life cycle effective proposed building design.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Selecting a life cycle effective proposed building design... Residential Buildings § 435.306 Selecting a life cycle effective proposed building design. In selecting... prototype, has the highest Net Savings or lowest total life cycle costs calculated in compliance with...

  17. 10 CFR 435.306 - Selecting a life cycle effective proposed building design.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Selecting a life cycle effective proposed building design... Residential Buildings § 435.306 Selecting a life cycle effective proposed building design. In selecting... prototype, has the highest Net Savings or lowest total life cycle costs calculated in compliance with...

  18. 10 CFR 435.306 - Selecting a life cycle effective proposed building design.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Selecting a life cycle effective proposed building design... Residential Buildings § 435.306 Selecting a life cycle effective proposed building design. In selecting... prototype, has the highest Net Savings or lowest total life cycle costs calculated in compliance with...

  19. 10 CFR 435.306 - Selecting a life cycle effective proposed building design.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Selecting a life cycle effective proposed building design... Residential Buildings § 435.306 Selecting a life cycle effective proposed building design. In selecting... prototype, has the highest Net Savings or lowest total life cycle costs calculated in compliance with...

  20. Water cycle and its management for plant habitats at reduced pressures.

    PubMed

    Rygalov, Vadim Y; Fowler, Philip A; Wheeler, Raymond M; Bucklin, Ray A

    2004-01-01

    Experimental and mathematical models were developed for describing and testing temperature and humidity parameters for plant production in bioregenerative life support systems. A factor was included for analyzing systems operating at low (10-101.3 kPa) pressure to reduce gas leakage and structural mass (e.g., inflatable greenhouses for space application). The expected close relationship between temperature and relative humidity was observed, along with the importance of heat exchanger coil temperature and air circulation rate. The presence of plants in closed habitats results in increased water flux through the system. Changes in pressure affect gas diffusion rates and surface boundary layers, and change convective transfer capabilities and water evaporation rates. A consistent observation from studies with plants at reduced pressures is increased evapotranspiration rates, even at constant vapor pressure deficits. This suggests that plant water status is a critical factor for managing low-pressure production systems. The approach suggested should help space mission planners design artificial environments in closed habitats.

  1. Water cycle and its management for plant habitats at reduced pressures

    NASA Technical Reports Server (NTRS)

    Rygalov, Vadim Y.; Fowler, Philip A.; Wheeler, Raymond M.; Bucklin, Ray A.

    2004-01-01

    Experimental and mathematical models were developed for describing and testing temperature and humidity parameters for plant production in bioregenerative life support systems. A factor was included for analyzing systems operating at low (10-101.3 kPa) pressure to reduce gas leakage and structural mass (e.g., inflatable greenhouses for space application). The expected close relationship between temperature and relative humidity was observed, along with the importance of heat exchanger coil temperature and air circulation rate. The presence of plants in closed habitats results in increased water flux through the system. Changes in pressure affect gas diffusion rates and surface boundary layers, and change convective transfer capabilities and water evaporation rates. A consistent observation from studies with plants at reduced pressures is increased evapotranspiration rates, even at constant vapor pressure deficits. This suggests that plant water status is a critical factor for managing low-pressure production systems. The approach suggested should help space mission planners design artificial environments in closed habitats.

  2. Managing the life cycle of electronic clinical documents.

    PubMed

    Payne, Thomas H; Graham, Gail

    2006-01-01

    To develop a model of the life cycle of clinical documents from inception to use in a person's medical record, including workflow requirements from clinical practice, local policy, and regulation. We propose a model for the life cycle of clinical documents as a framework for research on documentation within electronic medical record (EMR) systems. Our proposed model includes three axes: the stages of the document, the roles of those involved with the document, and the actions those involved may take on the document at each stage. The model includes the rules to describe who (in what role) can perform what actions on the document, and at what stages they can perform them. Rules are derived from needs of clinicians, and requirements of hospital bylaws and regulators. Our model encompasses current practices for paper medical records and workflow in some EMR systems. Commercial EMR systems include methods for implementing document workflow rules. Workflow rules that are part of this model mirror functionality in the Department of Veterans Affairs (VA) EMR system where the Authorization/ Subscription Utility permits document life cycle rules to be written in English-like fashion. Creating a model of the life cycle of clinical documents serves as a framework for discussion of document workflow, how rules governing workflow can be implemented in EMR systems, and future research of electronic documentation.

  3. Life-cycle assessment of Nebraska bridges.

    DOT National Transportation Integrated Search

    2013-05-01

    Life-cycle cost analysis (LCCA) is a necessary component in bridge management systems (BMSs) for : assessing investment decisions and identifying the most cost-effective improvement alternatives. The : LCCA helps to identify the lowest cost alternati...

  4. Underground Habitats in the Río Tinto Basin: A Model for Subsurface Life Habitats on Mars

    NASA Astrophysics Data System (ADS)

    Fernández-Remolar, David C.; Prieto-Ballesteros, Olga; Rodríguez, Nuria; Gómez, Felipe; Amils, Ricardo; Gómez-Elvira, Javier; Stoker, Carol R.

    2008-10-01

    A search for evidence of cryptic life in the subsurface region of a fractured Paleozoic volcanosedimentary deposit near the source waters of the Río Tinto River (Iberian pyrite belt, southwest Spain) was carried out by Mars Astrobiology Research and Technology Experiment (MARTE) project investigators in 2003 and 2004. This conventional deep-drilling experiment is referred to as the MARTE ground truth drilling project. Boreholes were drilled at three sites, and samples from extracted cores were analyzed with light microscopy, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy. Core leachates were analyzed with ion chromatography, and borehole fluids were analyzed with ion and gas chromatography. Key variables of the groundwater system (e.g. , pO2, pH, and salinity) exhibit huge ranges probably due to surficial oxygenation of overall reducing waters, physical mixing of waters, and biologically mediated water-rock interactions. Mineral distribution is mainly driven by the pH of subsurface solutions, which range from highly acidic to neutral. Borehole fluids contain dissolved gases such as CO2, CH4, and H2. SEM-EDS analyses of core samples revealed evidence of microbes attacking pyrite. The Río Tinto alteration mechanisms may be similar to subsurface weathering of the martian crust and provide insights into the possible (bio)geochemical cycles that may have accompanied underground habitats in extensive early Mars volcanic regions and associated sulfide ores.

  5. Underground habitats in the Río Tinto basin: a model for subsurface life habitats on Mars.

    PubMed

    Fernández-Remolar, David C; Prieto-Ballesteros, Olga; Rodríguez, Nuria; Gómez, Felipe; Amils, Ricardo; Gómez-Elvira, Javier; Stoker, Carol R

    2008-10-01

    A search for evidence of cryptic life in the subsurface region of a fractured Paleozoic volcanosedimentary deposit near the source waters of the Río Tinto River (Iberian pyrite belt, southwest Spain) was carried out by Mars Astrobiology Research and Technology Experiment (MARTE) project investigators in 2003 and 2004. This conventional deep-drilling experiment is referred to as the MARTE ground truth drilling project. Boreholes were drilled at three sites, and samples from extracted cores were analyzed with light microscopy, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy. Core leachates were analyzed with ion chromatography, and borehole fluids were analyzed with ion and gas chromatography. Key variables of the groundwater system (e.g., pO(2), pH, and salinity) exhibit huge ranges probably due to surficial oxygenation of overall reducing waters, physical mixing of waters, and biologically mediated water-rock interactions. Mineral distribution is mainly driven by the pH of subsurface solutions, which range from highly acidic to neutral. Borehole fluids contain dissolved gases such as CO(2), CH(4), and H(2). SEM-EDS analyses of core samples revealed evidence of microbes attacking pyrite. The Río Tinto alteration mechanisms may be similar to subsurface weathering of the martian crust and provide insights into the possible (bio)geochemical cycles that may have accompanied underground habitats in extensive early Mars volcanic regions and associated sulfide ores.

  6. Shifting the life-history paradigm: discovery of novel habitat use by hawksbill turtles.

    PubMed

    Gaos, Alexander R; Lewison, Rebecca L; Yañez, Ingrid L; Wallace, Bryan P; Liles, Michael J; Nichols, Wallace J; Baquero, Andres; Hasbún, Carlos R; Vasquez, Mauricio; Urteaga, José; Seminoff, Jeffrey A

    2012-02-23

    Adult hawksbill turtles (Eretmochelys imbricata) are typically described as open-coast, coral reef and hard substrate dwellers. Here, we report new satellite tracking data on female hawksbills from several countries in the eastern Pacific that revealed previously undocumented behaviour for adults of the species. In contrast to patterns of habitat use exhibited by their Caribbean and Indo-Pacific counterparts, eastern Pacific hawksbills generally occupied inshore estuaries, wherein they had strong associations with mangrove saltwater forests. The use of inshore habitats and affinities with mangrove saltwater forests presents a previously unknown life-history paradigm for adult hawksbill turtles and suggests a potentially unique evolutionary trajectory for the species. Our findings highlight the variability in life-history strategies that marine turtles and other wide-ranging marine wildlife may exhibit among ocean regions, and the importance of understanding such disparities from an ecological and management perspective.

  7. The Adult Life Spiral: A Critique of the Life Cycle Model.

    ERIC Educational Resources Information Center

    Stein, Peter; Etzkowitz, Henry

    We can identify and describe alternate paths of adulthood utilizing data from interviews with single adults. Our review of major models used in adulthood studies suggests that a developmental model, such as Daniel Levinson's life cycle model, is too tied to the notion of the imminent unfolding of the life course. The age-stratification theory…

  8. Life Cycle Cost Analysis Handbook. First Edition.

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education and Early Development, Juneau.

    This handbook presents guidelines on the Life Cycle Cost Analysis (LCCA) of building operations over the life of a building to assist school districts and consultants with evaluating proposed educational facility construction projects. It defines the terminology found in an LCCA, such as initial and future expenses, residual value, real discount…

  9. Life Cycle Cost of C-130E Weapon System.

    DTIC Science & Technology

    1977-07-01

    AFHRL-TR-7746 A-,I K lR FORCE g•r ___ FORCELIFE CYCLE COST OF C-130E WEAPON SYSTEM H By U Frank D. Brown "Gary A. WalkerU David H. WilsonBooing Awsp...I REPORT DOCUMENTO ON PAGE BEFORE COMPLETING FORM I?~ AFHR R.77-46 ( ~ LIFE CYCLE COST OF:C413A~ WEAPON SYSTEMteim.e M- 29 June 116- 3 June...human resources cost data life cycle cost historical weapon system analysis (I-WSA) inateuial resources 20). ABSTRACT (Con tinue on reverse siLa Mf

  10. Evolutionary lability of a complex life cycle in the aphid genus Brachycaudus.

    PubMed

    Emmanuelle, Jousselin; Gwenaelle, Genson; Armelle, Coeur d'acier

    2010-09-28

    Most aphid species complete their life cycle on the same set of host-plant species, but some (heteroecious species) alternate between different hosts, migrating from primary (woody) to secondary (herbaceous) host plants. The evolutionary processes behind the evolution of this complex life cycle have often been debated. One widely accepted scenario is that heteroecy evolved from monoecy on woody host plants. Several shifts towards monoecy on herbaceous plants have subsequently occurred and resulted in the radiation of aphids. Host alternation would have persisted in some cases due to developmental constraints preventing aphids from shifting their entire life cycle to herbaceous hosts (which are thought to be more favourable). According to this scenario, if aphids lose their primary host during evolution they should not regain it. The genus Brachycaudus includes species with all the types of life cycle (monoecy on woody plants, heteroecy, monoecy on herbs). We used this genus to test hypotheses concerning the evolution of life cycles in aphids. Phylogenetic investigation and character reconstruction suggest that life cycle is evolutionary labile in the genus. Though ancestral character states can be ambiguous depending on optimization methods, all analyses suggest that transitions from monoecy on herbs towards heteroecy have occurred several times. Transitions from heteroecy towards monoecy, are also likely. There have been many shifts in feeding behaviour but we found no significant correlation between life cycle changes and changes in diet. The transitions from monoecy on herbs towards heteroecy observed in this study go against a widely accepted evolutionary scenario: aphids in the genus Brachycaudus seem to be able to recapture their supposedly ancestral woody host. This suggests that the determinants of host alternation are probably not as complicated as previously thought. Definitive proofs of the lability of life cycle in Brachycaudus will necessitate

  11. Dealing with Emergy Algebra in the Life Cycle Assessment Framework

    EPA Science Inventory

    The Life Cycle Inventory (LCI) represents one of the four steps of the Life Cycle Assessment (LCA) methodology, which is a standardized procedure (ISO 14040:2006) to estimate the environmental impacts generated by the production, use and disposal of goods and services. In this co...

  12. [Life-cycles, psychopathology and suicidal behaviour].

    PubMed

    Osváth, Péter

    2012-12-01

    According to modern psychological theories the human life implies continuous development, the efficient solution of age-specific problems is necessary to the successful transition of age-periods. The phases of transition are very vulnerable against the accidental stressors and negative life-events. Thus the problem-solving capacity may run out, which impairs chance of the successful coping with stressful events. It may result in some negative consequences, such as different psychopathological symptoms (depression, anxiety, psychosis) or even suicidal behaviour. For that reason we have to pay special attention to the symptoms of psychological crisis and the presuicidal syndrome. In certain life-cycle transitions (such as adolescent, middle or elderly age) the personality has special vulnerability to the development of psychological and psychopathological problems. In this article the most important features of life-cycles and psychopathological symptoms are reviewed. The developmental and age-specific characteristics have special importance in understanding the background of the actual psychological crisis and improving the efficacy of the treatment. Using the complex bio-psycho-socio-spiritual approach not only the actual psychopatological problems, but the individual psychological features can be recognised. Thus the effective treatment relieves not only the actual symptoms, but will increase the chance for solving further crises.

  13. Mars extant-life campaign using an approach based on Earth-analog habitats

    NASA Technical Reports Server (NTRS)

    Palkovic, Lawrence A.; Wilson, Thomas J.

    2005-01-01

    The Mars Robotic Outpost group at JPL has identified sixteen potential momentous discoveries that if found on Mars would alter planning for the future Mars exploration program. This paper details one possible approach to the discovery of and response to the 'momentous discovery'' of extant life on Mars. The approach detailed in this paper, the Mars Extant-Life (MEL) campaign, is a comprehensive and flexible program to find living organisms on Mars by studying Earth-analog habitats of extremophile communities.

  14. NREL: U.S. Life Cycle Inventory Database - About the LCI Database Project

    Science.gov Websites

    About the LCI Database Project The U.S. Life Cycle Inventory (LCI) Database is a publicly available data collection and analysis methods. Finding consistent and transparent LCI data for life cycle and maintain the database. The 2009 U.S. Life Cycle Inventory (LCI) Data Stakeholder meeting was an

  15. High Cycle-life Shape Memory Polymer at High Temperature

    PubMed Central

    Kong, Deyan; Xiao, Xinli

    2016-01-01

    High cycle-life is important for shape memory materials exposed to numerous cycles, and here we report shape memory polyimide that maintained both high shape fixity (Rf) and shape recovery (Rr) during the more than 1000 bending cycles tested. Its critical stress is 2.78 MPa at 250 °C, and the shape recovery process can produce stored energy of 0.218 J g−1 at the efficiency of 31.3%. Its high Rf is determined by the large difference in storage modulus at rubbery and glassy states, while the high Rr mainly originates from its permanent phase composed of strong π-π interactions and massive chain entanglements. Both difference in storage modulus and overall permanent phase were preserved during the bending deformation cycles, and thus high Rf and Rr were observed in every cycle and the high cycle-life will expand application areas of SMPs enormously. PMID:27641148

  16. Habitat specialization through germination cueing: a comparative study of herbs from forests and open habitats.

    PubMed

    Ten Brink, Dirk-Jan; Hendriksma, Harmen Pieter; Bruun, Hans Henrik

    2013-02-01

    phases in the plant life cycle other than the established phase should be considered important in adaptive specialization.

  17. Life cycle replacement by gene introduction under an allee effect in periodical cicadas.

    PubMed

    Nariai, Yukiko; Hayashi, Saki; Morita, Satoru; Umemura, Yoshitaka; Tainaka, Kei-ichi; Sota, Teiji; Cooley, John R; Yoshimura, Jin

    2011-04-06

    Periodical cicadas (Magicicada spp.) in the USA are divided into three species groups (-decim, -cassini, -decula) of similar but distinct morphology and behavior. Each group contains at least one species with a 17-year life cycle and one with a 13-year cycle; each species is most closely related to one with the other cycle. One explanation for the apparent polyphyly of 13- and 17-year life cycles is that populations switch between the two cycles. Using a numerical model, we test the general feasibility of life cycle switching by the introduction of alleles for one cycle into populations of the other cycle. Our results suggest that fitness reductions at low population densities of mating individuals (the Allee effect) could play a role in life cycle switching. In our model, if the 13-year cycle is genetically dominant, a 17-year cycle population will switch to a 13-year cycle given the introduction of a few 13-year cycle alleles under a moderate Allee effect. We also show that under a weak Allee effect, different year-classes ("broods") with 17-year life cycles can be generated. Remarkably, the outcomes of our models depend only on the dominance relationships of the cycle alleles, irrespective of any fitness advantages.

  18. THE INTERNATIONAL WORKSHOP ON ELECTRICITY DATA FOR LIFE CYCLE INVENTORIES

    EPA Science Inventory

    A three day workshop was held in October 2001 to discuss life cycle inventory data for electricity production. Electricity was selected as the topic for discussion since it features very prominently in the LCA results for most product life cycles, yet there is no consistency in h...

  19. Technology development life cycle processes.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beck, David Franklin

    2013-05-01

    This report and set of appendices are a collection of memoranda originally drafted in 2009 for the purpose of providing motivation and the necessary background material to support the definition and integration of engineering and management processes related to technology development. At the time there was interest and support to move from Capability Maturity Model Integration (CMMI) Level One (ad hoc processes) to Level Three. As presented herein, the material begins with a survey of open literature perspectives on technology development life cycles, including published data on %E2%80%9Cwhat went wrong.%E2%80%9D The main thrust of the material presents a rational expose%CC%81more » of a structured technology development life cycle that uses the scientific method as a framework, with further rigor added from adapting relevant portions of the systems engineering process. The material concludes with a discussion on the use of multiple measures to assess technology maturity, including consideration of the viewpoint of potential users.« less

  20. Dry creek long-term watershed study: buffer zone performance as viable amphibian habitat

    Treesearch

    Brooke L. Talley; Thomas L. Crisman

    2006-01-01

    As bioindicators, amphibians typically require both terrestrial and aquatic habitats to complete their life cycles. Pre- timber-harvest monitoring (December 2002 through September 2003) of salamander and frog (Hylidae) populations was conducted in four watersheds of Decatur County, GA. Post- timber-harvest monitoring (December 2003 through September...

  1. An attributional life cycle assessment for an Italian residential multifamily building.

    PubMed

    Vitale, Pierluca; Arena, Umberto

    2017-09-06

    The study describes an attributional life cycle assessment carried out according to the ISO standards and focused on an Italian multifamily residential building. The aim was developing an exhaustive and reliable inventory of high-quality primary data, comparing the environmental impacts along the three stages of the building life cycle. The pre-use phase takes into account the production of all the construction materials, transportation, and on-site assembling. The use phase quantifies the resource consumptions for 50 years of the building utilization and ordinary maintenance. The end-of-life phase includes the building demolition and the management of generated wastes. The results quantify how the design criteria affect the environmental performances of the residential building along its life cycle. The role of the pre-use phase appears remarkable for global warming potential (GWP), due to the huge impacts of steel and concrete production processes. The use phase gives the largest contributions, which reach 77% and 84% of the total, for the categories of global warming and non-renewable energy. The end-of-life phase provides limited avoided impacts. A comparative analysis quantifies the improvements achievable with an alternative type of partitions and external walls. Acronyms: AC: air conditioning; C&DW: construction and demolition waste; CFL: compact fluorescent lamp; DHW: domestic hot water; EC: European Commission; EU: European Union; GDP: gross domestic product; GHG: greenhouse gases; GWP: global warming potential; LCA: life cycle assessment; LCI: life cycle inventory; LCIA: life cycle impact assessment; MFA: material flow analysis; NREP: non-renewable energy potential; RINP: respiratory inorganics potential; WFD: Waste Framework Directive.

  2. Addressing software security risk mitigations in the life cycle

    NASA Technical Reports Server (NTRS)

    Gilliam, David; Powell, John; Haugh, Eric; Bishop, Matt

    2003-01-01

    The NASA Office of Safety and Mission Assurance (OSMA) has funded the Jet Propulsion Laboratory (JPL) with a Center Initiative, 'Reducing Software Security Risk through an Integrated Approach' (RSSR), to address this need. The Initiative is a formal approach to addressing software security in the life cycle through the instantiation of a Software Security Assessment Instrument (SSAI) for the development and maintenance life cycles.

  3. Life cycles, fitness decoupling and the evolution of multicellularity.

    PubMed

    Hammerschmidt, Katrin; Rose, Caroline J; Kerr, Benjamin; Rainey, Paul B

    2014-11-06

    Cooperation is central to the emergence of multicellular life; however, the means by which the earliest collectives (groups of cells) maintained integrity in the face of destructive cheating types is unclear. One idea posits cheats as a primitive germ line in a life cycle that facilitates collective reproduction. Here we describe an experiment in which simple cooperating lineages of bacteria were propagated under a selective regime that rewarded collective-level persistence. Collectives reproduced via life cycles that either embraced, or purged, cheating types. When embraced, the life cycle alternated between phenotypic states. Selection fostered inception of a developmental switch that underpinned the emergence of collectives whose fitness, during the course of evolution, became decoupled from the fitness of constituent cells. Such development and decoupling did not occur when groups reproduced via a cheat-purging regime. Our findings capture key events in the evolution of Darwinian individuality during the transition from single cells to multicellularity.

  4. Design for life-cycle profit with simultaneous consideration of initial manufacturing and end-of-life remanufacturing

    NASA Astrophysics Data System (ADS)

    Kwak, Minjung; Kim, Harrison

    2015-01-01

    Remanufacturing is emerging as a promising solution for achieving green, profitable businesses. This article considers a manufacturer that produces new products and also remanufactured versions of the new products that become available at the end of their life cycle. For such a manufacturer, design decisions at the initial design stage determine both the current profit from manufacturing and future profit from remanufacturing. To maximize the total profit, design decisions must carefully consider both ends of product life cycle, i.e. manufacturing and end-of-life stages. This article proposes a decision-support model for the life-cycle design using mixed-integer nonlinear programming. With an aim to maximize the total life-cycle profit, the proposed model searches for an (at least locally) optimal product design (i.e. design specifications and the selling price) for the new and remanufactured products. It optimizes both the initial design and design upgrades at the end-of-life stage and also provides corresponding production strategies, including production quantities and take-back rate. The model is extended to a multi-objective model that maximizes both economic profit and environmental-impact saving. To illustrate, the developed model is demonstrated with an example of a desktop computer.

  5. Life cycle costs for Alaska bridges.

    DOT National Transportation Integrated Search

    2014-08-01

    A study was implemented to assist the Alaska Department of Transportation and Public Facilities (ADOT&PF) with life cycle costs for : the Alaska Highway Bridge Inventory. The study consisted of two parts. Part 1 involved working with regional offices...

  6. Models of the Organizational Life Cycle: Applications to Higher Education.

    ERIC Educational Resources Information Center

    Cameron, Kim S.; Whetten, David A.

    1983-01-01

    A review of models of group and organization life cycle development is provided and the applicability of those models for institutions of higher education are discussed. An understanding of the problems and characteristics present in different life cycle stages can help institutions manage transitions more effectively. (Author/MLW)

  7. Nascent life cycles and the emergence of higher-level individuality.

    PubMed

    Ratcliff, William C; Herron, Matthew; Conlin, Peter L; Libby, Eric

    2017-12-05

    Evolutionary transitions in individuality (ETIs) occur when formerly autonomous organisms evolve to become parts of a new, 'higher-level' organism. One of the first major hurdles that must be overcome during an ETI is the emergence of Darwinian evolvability in the higher-level entity (e.g. a multicellular group), and the loss of Darwinian autonomy in the lower-level units (e.g. individual cells). Here, we examine how simple higher-level life cycles are a key innovation during an ETI, allowing this transfer of fitness to occur 'for free'. Specifically, we show how novel life cycles can arise and lead to the origin of higher-level individuals by (i) mitigating conflicts between levels of selection, (ii) engendering the expression of heritable higher-level traits and (iii) allowing selection to efficiently act on these emergent higher-level traits. Further, we compute how canonical early life cycles vary in their ability to fix beneficial mutations via mathematical modelling. Life cycles that lack a persistent lower-level stage and develop clonally are far more likely to fix 'ratcheting' mutations that limit evolutionary reversion to the pre-ETI state. By stabilizing the fragile first steps of an evolutionary transition in individuality, nascent higher-level life cycles may play a crucial role in the origin of complex life.This article is part of the themed issue 'Process and pattern in innovations from cells to societies'. © 2017 The Author(s).

  8. Habitats of North American sea ducks.

    USGS Publications Warehouse

    Derksen, Dirk V.; Petersen, Margaret R.; Savard, Jean-Pierre L.

    2015-01-01

    Breeding, molting, fall and spring staging, and wintering habitats of the sea duck tribe Mergini are described based on geographic locations and distribution in North America, geomorphology, vegetation and soil types, and fresh water and marine characteristics. The dynamics of habitats are discussed in light of natural and anthropogenic events that shape areas important to sea ducks. Strategies for sea duck habitat management are outlined and recommendations for international collaboration to preserve key terrestrial and aquatic habitats are advanced. We follow the definition of habitat advanced by Odum (1971), which is the place or space where an organism lives. Weller (1999) emphasized that habitats for waterbirds required presence of sufficient resources (i.e., food, water, cover, space) for maintenance during a portion of their annual cycle. Habitats exploited by North American sea ducks are diverse, widespread across the continent and adjacent marine waters and until recently, most were only superficially known. A 15-year-long effort funded research on sea duck habitats through the Sea Duck Joint Venture and the Endangered or Threatened Species programs of the United States and Canada. Nevertheless, important gaps remain in our understanding of key elements required by some species during various life stages. Many significant habitats, especially staging and wintering sites, have been and continue to be destroyed or altered by anthropogenic activities. The goal of this chapter is to develop a comprehensive summary of marine, freshwater, and terrestrial habitats and their characteristics by considering sea duck species with similar needs as groups within the tribe Mergini. Additionally, we examine threats and changes to sea duck habitats from human-caused and natural events. Last, we evaluate conservation and management programs underway or available for maintenance and enhancement of habitats critical for sea ducks.

  9. Life cycle assessment: Existing building retrofit versus replacement

    NASA Astrophysics Data System (ADS)

    Darabi, Nura

    The embodied energy in building materials constitutes a large part of the total energy required for any building (Thormark 2001, 429). In working to make buildings more energy efficient this needs to be considered. Integrating considerations about life cycle assessment for buildings and materials is one promising way to reduce the amount of energy consumption being used within the building sector and the environmental impacts associated with that energy. A life cycle assessment (LCA) model can be utilized to help evaluate the embodied energy in building materials in comparison to the buildings operational energy. This thesis takes into consideration the potential life cycle reductions in energy and CO2 emissions that can be made through an energy retrofit of an existing building verses demolition and replacement with a new energy efficient building. A 95,000 square foot institutional building built in the 1960`s was used as a case study for a building LCA, along with a calibrated energy model of the existing building created as part of a previous Masters of Building Science thesis. The chosen case study building was compared to 10 possible improvement options of either energy retrofit or replacement of the existing building with a higher energy performing building in order to see the life cycle relationship between embodied energy, operational energy, and C02 emissions. As a result of completing the LCA, it is shown under which scenarios building retrofit saves more energy over the lifespan of the building than replacement with new construction. It was calculated that energy retrofit of the chosen existing institutional building would reduce the amount of energy and C02 emissions associated with that building over its life span.

  10. LIFE CYCLE ASSESSMENT: AN INTERNATIONAL EXPERIENCE

    EPA Science Inventory

    Life Cycle Assessment (LCA) is used to evaluate environmental burdens associated with a product, process or activity by identifying and quantifying relevant inputs and outputs of the defined system and evaluating their potential impacts. This article outlines the four components ...

  11. Shifting the life-history paradigm: discovery of novel habitat use by hawksbill turtles

    PubMed Central

    Gaos, Alexander R.; Lewison, Rebecca L.; Yañez, Ingrid L.; Wallace, Bryan P.; Liles, Michael J.; Nichols, Wallace J.; Baquero, Andres; Hasbún, Carlos R.; Vasquez, Mauricio; Urteaga, José; Seminoff, Jeffrey A.

    2012-01-01

    Adult hawksbill turtles (Eretmochelys imbricata) are typically described as open-coast, coral reef and hard substrate dwellers. Here, we report new satellite tracking data on female hawksbills from several countries in the eastern Pacific that revealed previously undocumented behaviour for adults of the species. In contrast to patterns of habitat use exhibited by their Caribbean and Indo-Pacific counterparts, eastern Pacific hawksbills generally occupied inshore estuaries, wherein they had strong associations with mangrove saltwater forests. The use of inshore habitats and affinities with mangrove saltwater forests presents a previously unknown life-history paradigm for adult hawksbill turtles and suggests a potentially unique evolutionary trajectory for the species. Our findings highlight the variability in life-history strategies that marine turtles and other wide-ranging marine wildlife may exhibit among ocean regions, and the importance of understanding such disparities from an ecological and management perspective. PMID:21880620

  12. Intersection life cycle cost comparison tool user guide version 1.0.

    DOT National Transportation Integrated Search

    2016-05-01

    The Intersection Life Cycle Cost Comparison Tool User Guide was developed as part of North : Carolina Department of Transportation Research Project No. 201411: Evaluation of Life Cycle : Impacts of Intersection Control Type Selection. : This sprea...

  13. Early-life origins of life-cycle well-being: research and policy implications.

    PubMed

    Currie, Janet; Rossin-Slater, Maya

    2015-01-01

    Mounting evidence across different disciplines suggests that early-life conditions can have consequences on individual outcomes throughout the life cycle. Relative to other developed countries, the United States fares poorly on standard indicators of early-life health, and this disadvantage may have profound consequences not only for population well-being, but also for economic growth and competitiveness in a global economy. In this paper, we first discuss the research on the strength of the link between early-life health and adult outcomes, and then provide an evidence-based review of the effectiveness of existing U.S. policies targeting the early-life environment. We conclude that there is a robust and economically meaningful relationship between early-life conditions and well-being throughout the life cycle, as measured by adult health, educational attainment, labor market attachment, and other indicators of socioeconomic status. However, there is some variation in the degree to which current policies in the United States are effective in improving early-life conditions. Among existing programs, some of the most effective are the Special Supplemental Program for Women, Infants, and Children (WIC), home visiting with nurse practitioners, and high-quality, center-based early-childhood care and education. In contrast, the evidence on other policies such as prenatal care and family leave is more mixed and limited.

  14. Life-Cycle Evaluation of Domestic Energy Systems

    NASA Astrophysics Data System (ADS)

    Bando, Shigeru; Hihara, Eiji

    Among the growing number of environmental issues, the global warming due to the increasing emission of greenhouse gases, such as carbon dioxide CO2, is the most serious one. In order to reduce CO2 emissions in energy use, it is necessary to reduce primary energy consumption, and to replace energy sources with alternatives that emit less CO2.One option of such ideas is to replace fossil gas for water heating with electricity generated by nuclear power, hydraulic power, and other methods with low CO2 emission. It is also important to use energy efficiently and to reduce waste heat. Co-generation system is one of the applications to be able to use waste heat from a generator as much as possible. The CO2 heat pump water heaters, the polymer electrolyte fuel cells, and the micro gas turbines have high potential for domestic energy systems. In the present study, the life-cycle cost, the life-cycle consumption of primary energy and the life-cycle emission of CO2 of these domestic energy systems are compare. The result shows that the CO2 heat pump water heaters have an ability to reduce CO2 emission by 10%, and the co-generation systems also have another ability to reduce primary energy consumption by 20%.

  15. Life Cycle Assessment of Wall Systems

    NASA Astrophysics Data System (ADS)

    Ramachandran, Sriranjani

    Natural resource depletion and environmental degradation are the stark realities of the times we live in. As awareness about these issues increases globally, industries and businesses are becoming interested in understanding and minimizing the ecological footprints of their activities. Evaluating the environmental impacts of products and processes has become a key issue, and the first step towards addressing and eventually curbing climate change. Additionally, companies are finding it beneficial and are interested in going beyond compliance using pollution prevention strategies and environmental management systems to improve their environmental performance. Life-cycle Assessment (LCA) is an evaluative method to assess the environmental impacts associated with a products' life-cycle from cradle-to-grave (i.e. from raw material extraction through to material processing, manufacturing, distribution, use, repair and maintenance, and finally, disposal or recycling). This study focuses on evaluating building envelopes on the basis of their life-cycle analysis. In order to facilitate this analysis, a small-scale office building, the University Services Building (USB), with a built-up area of 148,101 ft2 situated on ASU campus in Tempe, Arizona was studied. The building's exterior envelope is the highlight of this study. The current exterior envelope is made of tilt-up concrete construction, a type of construction in which the concrete elements are constructed horizontally and tilted up, after they are cured, using cranes and are braced until other structural elements are secured. This building envelope is compared to five other building envelope systems (i.e. concrete block, insulated concrete form, cast-in-place concrete, steel studs and curtain wall constructions) evaluating them on the basis of least environmental impact. The research methodology involved developing energy models, simulating them and generating changes in energy consumption due to the above mentioned

  16. Signal relay during the life cycle of Dictyostelium.

    PubMed

    Mahadeo, Dana C; Parent, Carole A

    2006-01-01

    A fundamental property of multicellular organisms is signal relay, the process by which information is transmitted from one cell to another. The integration of external information, such as nutritional status or developmental cues, is critical to the function of organisms. In addition, the spatial organizations of multicellular organisms require intricate signal relay mechanisms. Signal relay is remarkably exhibited during the life cycle of the social amoebae Dictyostelium discoideum, a eukaryote that retains a simple way of life, yet it has greatly contributed to our knowledge of the mechanisms cells use to communicate and integrate information. This chapter focuses on the molecules and mechanisms that Dictyostelium employs during its life cycle to relay temporal and spatial cues that are required for survival.

  17. Bypass control valve seal and bearing life cycle test report

    NASA Technical Reports Server (NTRS)

    Lundback, A. V.

    1972-01-01

    The operating characteristics of a bypass control valve seal and bearing life cycle tests are reported. Data from the initial assembly, leak, torque, and deflection tests are included along with the cycle life test results and conclusions. The equipment involved was to be used in the nuclear engine for the rocket vehicles program.

  18. Rapid Estimation of Life Cycle Inventory

    EPA Science Inventory

    Many chemical manufacturers and regulators use life cycle assessment (LCA) to manage the sustainability of chemical manufacturing processes. A significant challenge to using LCA, however, is the sheer quantity of data related to energy and material flows that needs to be collecte...

  19. LIFE CYCLE DESIGN OF A FUEL TANK SYSTEM

    EPA Science Inventory

    This life cycle design (LCD) project was a collaborative effort between the National Pollution Prevention Center at the University of Michigan, General Motors (GM), and the U.S. Environmental Protection Agency (EPA). The primary objective of this project was to apply life cyc...

  20. Design and life-cycle considerations for unconventional-reservoir wells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miskimins, J.L.

    2009-05-15

    This paper provides an overview of design and life-cycle considerations for certain unconventional-reservoir wells. An overview of unconventional-reservoir definitions is provided. Well design and life-cycle considerations are addressed from three aspects: upfront reservoir development, initial well completion, and well-life and long-term considerations. Upfront-reservoir-development issues discussed include well spacing, well orientation, reservoir stress orientations, and tubular metallurgy. Initial-well-completion issues include maximum treatment pressures and rates, treatment diversion, treatment staging, flowback and cleanup, and dewatering needs. Well-life and long-term discussions include liquid loading, corrosion, refracturing and associated fracture reorientation, and the cost of abandonment. These design considerations are evaluated with case studiesmore » for five unconventional-reservoir types: shale gas (Barnett shale), tight gas (Jonah feld), tight oil (Bakken play), coalbed methane (CBM) (San Juan basin), and tight heavy oil (Lost Hills field). In evaluating the life cycle and design of unconventional-reservoir wells, 'one size' does not fit all and valuable knowledge and a shortening of the learning curve can be achieved for new developments by studying similar, more-mature fields.« less

  1. A NGS approach to the encrusting Mediterranean sponge Crella elegans (Porifera, Demospongiae, Poecilosclerida): transcriptome sequencing, characterization and overview of the gene expression along three life cycle stages.

    PubMed

    Pérez-Porro, A R; Navarro-Gómez, D; Uriz, M J; Giribet, G

    2013-05-01

    Sponges can be dominant organisms in many marine and freshwater habitats where they play essential ecological roles. They also represent a key group to address important questions in early metazoan evolution. Recent approaches for improving knowledge on sponge biological and ecological functions as well as on animal evolution have focused on the genetic toolkits involved in ecological responses to environmental changes (biotic and abiotic), development and reproduction. These approaches are possible thanks to newly available, massive sequencing technologies-such as the Illumina platform, which facilitate genome and transcriptome sequencing in a cost-effective manner. Here we present the first NGS (next-generation sequencing) approach to understanding the life cycle of an encrusting marine sponge. For this we sequenced libraries of three different life cycle stages of the Mediterranean sponge Crella elegans and generated de novo transcriptome assemblies. Three assemblies were based on sponge tissue of a particular life cycle stage, including non-reproductive tissue, tissue with sperm cysts and tissue with larvae. The fourth assembly pooled the data from all three stages. By aggregating data from all the different life cycle stages we obtained a higher total number of contigs, contigs with blast hit and annotated contigs than from one stage-based assemblies. In that multi-stage assembly we obtained a larger number of the developmental regulatory genes known for metazoans than in any other assembly. We also advance the differential expression of selected genes in the three life cycle stages to explore the potential of RNA-seq for improving knowledge on functional processes along the sponge life cycle. © 2013 Blackwell Publishing Ltd.

  2. Robotic ecological mapping: Habitats and the search for life in the Atacama Desert

    NASA Astrophysics Data System (ADS)

    Warren-Rhodes, K.; Weinstein, S.; Piatek, J. L.; Dohm, J.; Hock, A.; Minkley, E.; Pane, D.; Ernst, L. A.; Fisher, G.; Emani, S.; Waggoner, A. S.; Cabrol, N. A.; Wettergreen, D. S.; Grin, E.; Coppin, P.; Diaz, Chong; Moersch, J.; Oril, G. G.; Smith, T.; Stubbs, K.; Thomas, G.; Wagner, M.; Wyatt, M.; Boyle, L. Ng

    2007-12-01

    As part of the three-year `Life in the Atacama' (LITA) project, plant and microbial abundance were mapped within three sites in the Atacama Desert, Chile, using an automated robotic rover. On-board fluorescence imaging of six biological signatures (e.g., chlorophyll, DNA, proteins) was used to assess abundance, based on a percent positive sample rating system and standardized robotic ecological transects. The percent positive rating system scored each sample based on the measured signal strength (0 for no signal to 2 for strong signal) for each biological signature relative to the total rating possible. The 2005 field experiment results show that percent positive ratings varied significantly across Site D (coastal site with fog), with patchy zones of high abundance correlated with orbital and microscale habitat types (heaved surface crust and gravel bars); alluvial fan habitats generally had lower abundance. Non-random multi-scale biological patchiness also characterized interior desert Sites E and F, with relatively high abundance associated with (paleo)aqueous habitats such as playas. Localized variables, including topography, played an important, albeit complex, role in microbial spatial distribution. Site D biosignature trends correlated with culturable soil bacteria, with MPN ranging from 10-1000 CFU/g-soil, and chlorophyll ratings accurately mapped lichen/moss abundance (Site D) and higher plant (Site F) distributions. Climate also affected biological patchiness, with significant correlation shown between abundance and (rover) air relative humidity, while lichen patterns were linked to the presence of fog. Rover biological mapping results across sites parallel longitudinal W-E wet/dry/wet Atacama climate trends. Overall, the study highlights the success of targeting of aqueous-associated habitats identifiable from orbital geology and mineralogy. The LITA experience also suggests the terrestrial study of life and its distribution, particularly the fields of

  3. Life cycle impacts of manufacturing redwood decking in Northern California

    Treesearch

    Richard D. Bergman; Elaine Oneil; Ivan L. Eastin; Han-Sup Han

    2014-01-01

    Awareness of the environmental footprint of building construction and use has led to increasing interest in green building. Defining a green building is an evolving process with life cycle inventory and life cycle impact assessment (LCIA) emerging as key tools in that evolution and definition process. This study used LCIA to determine the environmental footprint...

  4. The evolution of coloniality in birds in relation to food, habitat, predation, and life-history traits: a comparative analysis.

    PubMed

    Rolland, C; Danchin, E; de Fraipont, M

    1998-06-01

    Coloniality in birds has been intensively studied under the cost and benefit approach, but no general conclusion can be given concerning its evolutionary function. Here, we report on a comparative analysis carried out on 320 species of birds using the general method of comparative analysis for discrete variables and the contrast method to analyze the evolution of coloniality. Showing a mean of 23 convergences and 10 reversals, coloniality appears to be a rather labile trait. Colonial breeding appears strongly correlated with the absence of feeding territory, the aquatic habitat, and nest exposure to predators but was not correlated with changes in life-history traits (body mass and clutch size). The correlation of coloniality with the aquatic habitat is in fact explained by a strong correlation with the marine habitat. Unexpectedly, we found that the evolution toward a marine habitat in birds was contingent on coloniality and that coloniality evolved before the passage to a marine life. These results-along with the lack of transitions from the nonmarine to marine habitat in solitary species and the precedence of the loss of feeding territoriality on the passage to a marine life-contradict most of the hypotheses classically accepted to explain coloniality and suggest that we use a different framework to study this evolutionary enigma.

  5. A Darwinian approach to the origin of life cycles with group properties.

    PubMed

    Rashidi, Armin; Shelton, Deborah E; Michod, Richard E

    2015-06-01

    A selective explanation for the evolution of multicellular organisms from unicellular ones requires knowledge of both selective pressures and factors affecting the response to selection. Understanding the response to selection is particularly challenging in the case of evolutionary transitions in individuality, because these transitions involve a shift in the very units of selection. We develop a conceptual framework in which three fundamental processes (growth, division, and splitting) are the scaffold for unicellular and multicellular life cycles alike. We (i) enumerate the possible ways in which these processes can be linked to create more complex life cycles, (ii) introduce three genes based on growth, division and splitting that, acting in concert, determine the architecture of the life cycles, and finally, (iii) study the evolution of the simplest five life cycles using a heuristic model of coupled ordinary differential equations in which mutations are allowed in the three genes. We demonstrate how changes in the regulation of three fundamental aspects of colonial form (cell size, colony size, and colony cell number) could lead unicellular life cycles to evolve into primitive multicellular life cycles with group properties. One interesting prediction of the model is that selection generally favors cycles with group level properties when intermediate body size is associated with lowest mortality. That is, a universal requirement for the evolution of group cycles in the model is that the size-mortality curve be U-shaped. Furthermore, growth must decelerate with size. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. [TRANSFORMATIONS OF LIFE CYCLES IN THE EVOLUTIONARY HISTORY OF TRYPANOSOMATIDAE. EXOTRANSFORMATIONS].

    PubMed

    Frolov, A O; Malysheva, M N; Kostygov, A Yu

    2015-01-01

    The present review is devoted to the analysis of exotransformations of life cycles in the evolutionary history of trypanosomatids (Kinetoplastea: Trypanosomatidae). Exotransformations are treated as processes associated with the transition of a trypanosomatid to a new host. The result of these transformations comprises both the inclusion of new hosts in life cycles of parasites and also epy formation of parasitic systems de novo. It is shown that exotransformations are one of the main modi in the evolution of trypanosomatids. Different examples of exotransformations of life cycle in all the taxonomic groups of Trypanosomatidae are given.

  7. [TRANSFORMATIONS OF LIFE CYCLES IN THE EVOLUTIONARY HISTORY OF TRYPANOSOMATIDS. MACROTRANSFORMATIONS].

    PubMed

    Frolov, A O; Malysheva, M N; Kostygov, A Yu

    2015-01-01

    The review concerns analysis of life cycle macrotransformations in the evolutionary history of trypanosomatids. The term "macrotransformations" stands for evolutionary processes leading to the establishment of heteroxenous and secondary homoxenous life cycles within Trypanosomatidae. There were three direct macrotransformations in the evolution of the group resulting in the rise of heteroxenous genera Leishmania, Trypanosoma and Phytomonas, and one case of reverse macrotransformation in trypanosomes of T. (b.) brucei group. The issues of the origin, diversity and phylogeny of taxa whose emergence resulted from macrotransformations of life cycles of homoxenous trypanosomatids.

  8. Security Risks: Management and Mitigation in the Software Life Cycle

    NASA Technical Reports Server (NTRS)

    Gilliam, David P.

    2004-01-01

    A formal approach to managing and mitigating security risks in the software life cycle is requisite to developing software that has a higher degree of assurance that it is free of security defects which pose risk to the computing environment and the organization. Due to its criticality, security should be integrated as a formal approach in the software life cycle. Both a software security checklist and assessment tools should be incorporated into this life cycle process and integrated with a security risk assessment and mitigation tool. The current research at JPL addresses these areas through the development of a Sotfware Security Assessment Instrument (SSAI) and integrating it with a Defect Detection and Prevention (DDP) risk management tool.

  9. A life cycle assessment of destruction of ammunition.

    PubMed

    Alverbro, K; Björklund, A; Finnveden, G; Hochschorner, E; Hägvall, J

    2009-10-30

    The Swedish Armed Forces have large stocks of ammunition that were produced at a time when decommissioning was not considered. This ammunition will eventually become obsolete and must be destroyed, preferably with minimal impact on the environment and in a safe way for personnel. The aim of this paper is to make a comparison of the environmental impacts in a life cycle perspective of three different methods of decommissioning/destruction of ammunition, and to identify the environmental advantages and disadvantages of each of these destruction methods: open detonation; static kiln incineration with air pollution control combined with metal recycling, and a combination of incineration with air pollution control, open burning, recovery of some energetic material and metal recycling. Data used are for the specific processes and from established LCA databases. Recycling the materials in the ammunition and minimising the spread of airborne pollutants during incineration were found to be the most important factors affecting the life cycle environmental performance of the compared destruction methods. Open detonation with or without metal recycling proved to be the overall worst alternative from a life cycle perspective. The results for the static kiln and combination treatment indicate that the kind of ammunition and location of the destruction plant might determine the choice of method, since the environmental impacts from these methods are of little difference in the case of this specific grenade. Different methods for destruction of ammunition have previously been discussed from a risk and safety perspective. This is however to our knowledge the first study looking specifically on environmentally aspect in a life cycle perspective.

  10. Life cycles of dominant mayflies (Ephemeroptera) on a torrent of the high Bolivian Andes

    PubMed

    Molina, Carlos I; Puliafico, Kenneth P

    2016-03-01

    The mayflies of the temperate and cold zones have well-synchronized life cycles, distinct cohorts, short emergence and flight periods. In contrast, aquatic insects from the tropical zones are characterized by multivoltine life cycles, “non-discernible cohorts” and extended flight periods throughout the year. This report is the first observation of life cycle patterns made of two species of mayflies on a torrent in the high elevation Bolivian Andes. The samples were taken from four sites and four periods during a hydrological season. The life cycle of each species was examined using size-class frequency analysis and a monthly modal progression model (von Bertalanffy’s model) to infer the life cycle synchrony type. These first observations showed a moderately synchronized univoltine life cycle for Andesiops peruvianus (Ulmer, 1920), whereas Meridialaris tintinnabula Pescador and Peters (1987), had an unsynchronized multivoltine life cycle. These results showed that the generalization of all aquatic insects as unsynchronized multivoltine species in the Andean region may not be entirely accurate since there is still a need to further clarify the life cycle patterns of the wide variety of aquatic insects living in this high elevation tropical environment.

  11. The Effects of the Wildlife Habitat Evaluation Program on Targeted Life Skills

    ERIC Educational Resources Information Center

    Allen, Kevin; Elmore, R. Dwayne

    2012-01-01

    Does participation in the Wildlife Habitat Evaluation Program (WHEP) help develop life skills? 4-H members and coaches who participated in the National WHEP Contest between the years 2003-2005 and 2007-2009 were asked to complete an evaluation at the end of each contest. A portion of the evaluation asked participants and coaches to determine if…

  12. Comparative muscle development of scyphozoan jellyfish with simple and complex life cycles.

    PubMed

    Helm, Rebecca R; Tiozzo, Stefano; Lilley, Martin K S; Lombard, Fabien; Dunn, Casey W

    2015-01-01

    Simple life cycles arise from complex life cycles when one or more developmental stages are lost. This raises a fundamental question - how can an intermediate stage, such as a larva, be removed, and development still produce a normal adult? To address this question, we examined the development in several species of pelagiid jellyfish. Most members of Pelagiidae have a complex life cycle with a sessile polyp that gives rise to ephyrae (juvenile medusae); but one species within Pelagiidae, Pelagia noctiluca, spends its whole life in the water column, developing from a larva directly into an ephyra. In many complex life cycles, adult features develop from cell populations that remain quiescent in larvae, and this is known as life cycle compartmentalization and may facilitate the evolution of direct life cycles. A second type of metamorphic processes, known as remodeling, occurs when adult features are formed through modification of already differentiated larval structures. We examined muscle morphology to determine which of these alternatives may be present in Pelagiidae. We first examined the structure and development of polyp and ephyra musculature in Chrysaora quinquecirrha, a close relative of P. noctiluca with a complex life cycle. Using phallotoxin staining and confocal microscopy, we verified that polyps have four to six cord muscles that persist in strobilae and discovered that cord muscles is physically separated from ephyra muscle. When cord muscle is removed from ephyra segments, normal ephyra muscle still develops. This suggests that polyp cord muscle is not necessary for ephyra muscle formation. We also found no evidence of polyp-like muscle in P. noctiluca. In both species, we discovered that ephyra muscle arises de novo in a similar manner, regardless of the life cycle. The separate origins of polyp and ephyra muscle in C. quinquecirrha and the absence of polyp-like muscle in P. noctiluca suggest that polyp muscle is not remodeled to form ephyra muscle

  13. Life Cycle Characterization of Sulfolobus Monocaudavirus 1, an Extremophilic Spindle-Shaped Virus with Extracellular Tail Development

    PubMed Central

    Uldahl, Kristine B.; Jensen, Signe B.; Bhoobalan-Chitty, Yuvaraj; Martínez-Álvarez, Laura; Papathanasiou, Pavlos

    2016-01-01

    ABSTRACT We provide here, for the first time, insights into the initial infection stages of a large spindle-shaped archaeal virus and explore the following life cycle events. Our observations suggest that Sulfolobus monocaudavirus 1 (SMV1) exhibits a high adsorption rate and that virions adsorb to the host cells via three distinct attachment modes: nosecone association, body association, and body/tail association. In the body/tail association mode, the entire virion, including the tail(s), aligns to the host cell surface and the main body is greatly flattened, suggesting a possible fusion entry mechanism. Upon infection, the intracellular replication cycle lasts about 8 h, at which point the virions are released as spindle-shaped tailless particles. Replication of the virus retarded host growth but did not cause lysis of the host cells. Once released from the host and at temperatures resembling that of its natural habitat, SMV1 starts developing one or two tails. This exceptional property of undergoing a major morphological development outside, and independently of, the host cell has been reported only once before for the related Acidianus two-tailed virus. Here, we show that SMV1 can develop tails of more than 900 nm in length, more than quadrupling the total virion length. IMPORTANCE Very little is known about the initial life cycle stages of viruses infecting hosts of the third domain of life, Archaea. This work describes the first example of an archaeal virus employing three distinct association modes. The virus under study, Sulfolobus monocaudavirus 1, is a representative of the large spindle-shaped viruses that are frequently found in acidic hot springs. The results described here will add valuable knowledge about Archaea, the least studied domain in the virology field. PMID:27053548

  14. Life Cycle Characterization of Sulfolobus Monocaudavirus 1, an Extremophilic Spindle-Shaped Virus with Extracellular Tail Development.

    PubMed

    Uldahl, Kristine B; Jensen, Signe B; Bhoobalan-Chitty, Yuvaraj; Martínez-Álvarez, Laura; Papathanasiou, Pavlos; Peng, Xu

    2016-06-15

    We provide here, for the first time, insights into the initial infection stages of a large spindle-shaped archaeal virus and explore the following life cycle events. Our observations suggest that Sulfolobus monocaudavirus 1 (SMV1) exhibits a high adsorption rate and that virions adsorb to the host cells via three distinct attachment modes: nosecone association, body association, and body/tail association. In the body/tail association mode, the entire virion, including the tail(s), aligns to the host cell surface and the main body is greatly flattened, suggesting a possible fusion entry mechanism. Upon infection, the intracellular replication cycle lasts about 8 h, at which point the virions are released as spindle-shaped tailless particles. Replication of the virus retarded host growth but did not cause lysis of the host cells. Once released from the host and at temperatures resembling that of its natural habitat, SMV1 starts developing one or two tails. This exceptional property of undergoing a major morphological development outside, and independently of, the host cell has been reported only once before for the related Acidianus two-tailed virus. Here, we show that SMV1 can develop tails of more than 900 nm in length, more than quadrupling the total virion length. Very little is known about the initial life cycle stages of viruses infecting hosts of the third domain of life, Archaea This work describes the first example of an archaeal virus employing three distinct association modes. The virus under study, Sulfolobus monocaudavirus 1, is a representative of the large spindle-shaped viruses that are frequently found in acidic hot springs. The results described here will add valuable knowledge about Archaea, the least studied domain in the virology field. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  15. Residential Mobility, Age, and the Life Cycle

    ERIC Educational Resources Information Center

    Yee, William; Arsdol, Maurice D. Van, Jr.

    1977-01-01

    A life cycle explanation of residential mobility is presented. It posits that age-related events in a normative context influence moving probabilities for homogeneous populations who have relatively uniform socialization. (Author)

  16. Development of high-rise buildings: digitalization of life cycle management

    NASA Astrophysics Data System (ADS)

    Gusakova, Elena

    2018-03-01

    The analysis of the accumulated long-term experience in the construction and operation of high-rise buildings reveals not only the engineering specificity of such projects, but also systemic problems in the field of project management. Most of the project decisions are made by the developer and the investor in the early stages of the life cycle - from the acquisition of the site to the start of operation, so most of the participants in the construction and operation of the high-rise building are far from the strategic life-cycle management of the project. The solution of these tasks due to the informatization of management has largely exhausted its efficiency resource. This is due to the fact that the applied IT-systems automated traditional "inherited" processes and management structures, and, in addition, they were focused on informatization of the activities of the construction company, rather than the construction project. Therefore, in the development of high-rise buildings, the tasks of researching approaches and methods for managing the full life cycle of projects that will improve their competitiveness become topical. For this purpose, the article substantiates the most promising approaches and methods of informational modeling of high-rise construction as a basis for managing the full life cycle of this project. Reengineering of information interaction schemes for project participants is considered; formation of a unified digital environment for the life cycle of the project; the development of systems for integrating data management and project management.

  17. Life cycle greenhouse gas emissions and freshwater consumption of Marcellus shale gas.

    PubMed

    Laurenzi, Ian J; Jersey, Gilbert R

    2013-05-07

    We present results of a life cycle assessment (LCA) of Marcellus shale gas used for power generation. The analysis employs the most extensive data set of any LCA of shale gas to date, encompassing data from actual gas production and power generation operations. Results indicate that a typical Marcellus gas life cycle yields 466 kg CO2eq/MWh (80% confidence interval: 450-567 kg CO2eq/MWh) of greenhouse gas (GHG) emissions and 224 gal/MWh (80% CI: 185-305 gal/MWh) of freshwater consumption. Operations associated with hydraulic fracturing constitute only 1.2% of the life cycle GHG emissions, and 6.2% of the life cycle freshwater consumption. These results are influenced most strongly by the estimated ultimate recovery (EUR) of the well and the power plant efficiency: increase in either quantity will reduce both life cycle freshwater consumption and GHG emissions relative to power generated at the plant. We conclude by comparing the life cycle impacts of Marcellus gas and U.S. coal: The carbon footprint of Marcellus gas is 53% (80% CI: 44-61%) lower than coal, and its freshwater consumption is about 50% of coal. We conclude that substantial GHG reductions and freshwater savings may result from the replacement of coal-fired power generation with gas-fired power generation.

  18. BROAD-BASED ENVIRONMENTAL LIFE CYCLE ASSESSMENT

    EPA Science Inventory

    Pollution prevention through Life Cycle Assessment (LCA) is a departure from evaluating waste management options that look mainly at single issues such as recyclability or reduced toxicity. An LCA is a snapshot in time of inputs and outputs. It can be used as an objective technic...

  19. Building Maintenance and Repair Data for Life-Cycle Cost Analyses: Electrical Systems.

    DTIC Science & Technology

    1991-05-01

    Repair Data for Life-Cycle Cost Analyses: Electrical Systems by Edgar S. Neely Robert D. Neathammer James R. Stirn Robert P. Winkler This research...systems have been developed to assist planners in preparing DD Form 1391 documentation, designers in life-cycle cost component selection, and maintainers...Maintenance and Repair Data for Life-Cycle Cost Analyses: RDTE dated 1980 Electrical Systems REIMB 1984 - 1989 6. AUTH4OR(S) Edgar S. Neely, Robert D

  20. Conceptual Framework To Extend Life Cycle Assessment ...

    EPA Pesticide Factsheets

    Life Cycle Assessment (LCA) is a decision-making tool that accounts for multiple impacts across the life cycle of a product or service. This paper presents a conceptual framework to integrate human health impact assessment with risk screening approaches to extend LCA to include near-field chemical sources (e.g., those originating from consumer products and building materials) that have traditionally been excluded from LCA. A new generation of rapid human exposure modeling and high-throughput toxicity testing is transforming chemical risk prioritization and provides an opportunity for integration of screening-level risk assessment (RA) with LCA. The combined LCA and RA approach considers environmental impacts of products alongside risks to human health, which is consistent with regulatory frameworks addressing RA within a sustainability mindset. A case study is presented to juxtapose LCA and risk screening approaches for a chemical used in a consumer product. The case study demonstrates how these new risk screening tools can be used to inform toxicity impact estimates in LCA and highlights needs for future research. The framework provides a basis for developing tools and methods to support decision making on the use of chemicals in products. This paper presents a conceptual framework for including near-field exposures into Life Cycle Assessment using advanced human exposure modeling and high-throughput tools

  1. NREL, Johns Hopkins SAIS Develop Method to Quantify Life Cycle Land Use of

    Science.gov Websites

    Life Cycle Land Use of Electricity from Natural Gas News Release: NREL, Johns Hopkins SAIS Develop Method to Quantify Life Cycle Land Use of Electricity from Natural Gas October 2, 2017 A case study of time provides quantifiable information on the life cycle land use of generating electricity from

  2. Loss and modification of habitat

    USGS Publications Warehouse

    Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.; Wilkinson, John W.; Heatwole, Harold

    2012-01-01

    water balance (Thorson and Svihla 1943; Brattstrom 1963; Tracy 1976). Hence, individuals require and seek specific microhabitats that maintain their preferred body temperature while at the same time reducing water loss or allowing individuals to re-hydrate. Amphibians also possess relatively few physical attributes that protect them from predators. Although they may avoid predators behaviourally or deter them by skin toxins, amphibians lack defensive shells or hardened cuticles, do not have protective teeth or claws, and most are insufficiently fast to escape predators. Hence, they are relatively dependent on sites that conceal or protect them from predation. Most amphibians also differ significantly from other vertebrates in possessing a complex two-phase life cycle: the pre-metamorphic larval (tadpole) stage and the post-metamorphic juvenile and adult stage (Wilbur 1980, 1984). Most amphibian species have two distinct econes (Heatwole 1989), each with different habitat requirements, the larvae being aquatic and the post-metamorphic animals more terrestrial. The habitats required by the two phases can differ greatly, but both are essential to the survival of a species. However, amphibian diversity is great and exceptions to this general pattern exist. For example, some species have direct development without going through a larval stage and are fully terrestrial, whereas the larvae of other species can reach sexual maturity without going through metamorphosis (i.e., neoteny) and are fully aquatic.

  3. A comparison of major petroleum life cycle models | Science ...

    EPA Pesticide Factsheets

    Many organizations have attempted to develop an accurate well-to-pump life cycle model of petroleum products in order to inform decision makers of the consequences of its use. Our paper studies five of these models, demonstrating the differences in their predictions and attempting to evaluate their data quality. Carbon dioxide well-to-pump emissions for gasoline showed a variation of 35 %, and other pollutants such as ammonia and particulate matter varied up to 100 %. Differences in allocation do not appear to explain differences in predictions. Effects of these deviations on well-to-wheels passenger vehicle and truck transportation life cycle models may be minimal for effects such as global warming potential (6 % spread), but for respiratory effects of criteria pollutants (41 % spread) and other impact categories, they can be significant. A data quality assessment of the models’ documentation revealed real differences between models in temporal and geographic representativeness, completeness, as well as transparency. Stakeholders may need to consider carefully the tradeoffs inherent when selecting a model to conduct life cycle assessments for systems that make heavy use of petroleum products. This is a qualitative and quantitative comparison of petroleum LCA models intended for an expert audience interested in better understanding the data quality of existing petroleum life cycle models and the quantitative differences between these models.

  4. Linking movement and reproductive history of brook trout to assess habitat connectivity in a heterogeneous stream network

    USGS Publications Warehouse

    Kanno, Yoichiro; Letcher, Benjamin H.; Coombs, Jason A.; Nislow, Keith H.; Whiteley, Andrew R.

    2013-01-01

    This study highlighted the importance of characterising animal movement over the life cycle for inferring habitat connectivity accurately. Such movements of individuals can contribute to substantial gene movements in a fecund species characterised by high variation in reproductive success.

  5. Chopper-controlled discharge life cycling studies on lead-acid batteries

    NASA Technical Reports Server (NTRS)

    Kraml, J. J.; Ames, E. P.

    1982-01-01

    State-of-the-art 6 volt lead-acid golf car batteries were tested. A daily charge/discharge cycling to failure points under various chopper controlled pulsed dc and continuous current load conditions was undertaken. The cycle life and failure modes were investigated for depth of discharge, average current chopper frequency, and chopper duty cycle. It is shown that battery life is primarily and inversely related to depth of discharge and discharge current. Failure mode is characterized by a gradual capacity loss with consistent evidence of cell element aging.

  6. MAKING LIFE CYCLE INVENTORY DATA AVAILABLE

    EPA Science Inventory

    Making Life Cycle Inventory Data Available

    Mary Ann Curran
    US EPA, National Risk Management Research Laboratory
    Address: 26 W. Martin Luther King Drive (MS-466)
    Cincinnati, OH 45268 USA
    Phone: 513-569-7782
    Fax: 513-569-7111
    E-Mail: curran.maryann@...

  7. Use of riverine through reef habitat systems by dog snapper ( Lutjanus jocu ) in eastern Brazil

    NASA Astrophysics Data System (ADS)

    Moura, Rodrigo L.; Francini-Filho, Ronaldo B.; Chaves, Eduardo M.; Minte-Vera, Carolina V.; Lindeman, Kenyon C.

    2011-11-01

    The early life history of Western Atlantic snappers from the Southern hemisphere is largely unknown. Habitat use of different life stages (i.e. size categories) of the dog snapper ( Lutjanus jocu) was examined across the largest South Atlantic reef-estuarine complex (Abrolhos Shelf, Brazil, 16-19° S). Visual surveys were conducted in different habitats across the shelf (estuary, inner-shelf reefs and mid-shelf reefs). Lutjanus jocu showed higher densities on inner-shelf habitats, with a clear increase in fish size across the shelf. Individuals <7 cm were associated with both the estuary (mangrove and rocky habitats) and inner-shelf reefs (particularly shallow fore-reefs and tide pools). Individuals ranging 10-30 cm were broadly distributed, but consistently more abundant on inner-shelf reefs. Individuals between 30 and 40 cm were more common on mid-shelf reefs, while individuals >40 cm were recorded only on mid-shelf reefs. Literature data indicate that individuals ranging 70-80 cm are common on deep offshore reefs. This pattern suggests that the dog snapper performs ontogenetic cross-shelf migrations. Protecting portions of the different habitats used by the dog snapper during its post-settlement life cycle is highlighted as an important conservation and management measure.

  8. LIFE CYCLE DESIGN FRAMEWORK AND DEMONSTRATION PROJECTS PROFILES OF AT&T AND ALLIED SIGNAL

    EPA Science Inventory

    Life cycle design seeks to minimize the environmental burden associated with a product life cycle from raw materials acquisition through manufacturing, use, and end-of-life management. ife cycle design emphasizes integrating environmental requirements into the earliest phases of ...

  9. LCIA framework and cross-cutting issues guidance within the UNEP/SETAC Life Cycle Initiative

    EPA Science Inventory

    Increasing needs for decision support and advances in scientific knowledge within life cycle assessment (LCA) led to substantial efforts to provide global guidance on environmental life cycle impact assessment (LCIA) indicators under the auspices of the UNEP-SETAC Life Cycle Init...

  10. Life cycle cost modeling of conceptual space vehicles

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles

    1993-01-01

    This paper documents progress to date by the University of Dayton on the development of a life cycle cost model for use during the conceptual design of new launch vehicles and spacecraft. This research is being conducted under NASA Research Grant NAG-1-1327. This research effort changes the focus from that of the first two years in which a reliability and maintainability model was developed to the initial development of a life cycle cost model. Cost categories are initially patterned after NASA's three axis work breakdown structure consisting of a configuration axis (vehicle), a function axis, and a cost axis. The focus will be on operations and maintenance costs and other recurring costs. Secondary tasks performed concurrent with the development of the life cycle costing model include continual support and upgrade of the R&M model. The primary result of the completed research will be a methodology and a computer implementation of the methodology to provide for timely cost analysis in support of the conceptual design activities. The major objectives of this research are: to obtain and to develop improved methods for estimating manpower, spares, software and hardware costs, facilities costs, and other cost categories as identified by NASA personnel; to construct a life cycle cost model of a space transportation system for budget exercises and performance-cost trade-off analysis during the conceptual and development stages; to continue to support modifications and enhancements to the R&M model; and to continue to assist in the development of a simulation model to provide an integrated view of the operations and support of the proposed system.

  11. FUNDAMENTALS OF LIFE CYCLE ASSESSMENT AND OFF-THE-SHELF SOFTWARE DEMONSTRATION

    EPA Science Inventory

    As the name implies, Life Cycle Assesssment (LCA) evaluates the entire life cycle of a product, process, activity, or service, not just simple economics at the time of delivery. This course on LCA covers the following issues:
    Basic principles of LCA for use in producing, des...

  12. Fragmentation modes and the evolution of life cycles.

    PubMed

    Pichugin, Yuriy; Peña, Jorge; Rainey, Paul B; Traulsen, Arne

    2017-11-01

    Reproduction is a defining feature of living systems. To reproduce, aggregates of biological units (e.g., multicellular organisms or colonial bacteria) must fragment into smaller parts. Fragmentation modes in nature range from binary fission in bacteria to collective-level fragmentation and the production of unicellular propagules in multicellular organisms. Despite this apparent ubiquity, the adaptive significance of fragmentation modes has received little attention. Here, we develop a model in which groups arise from the division of single cells that do not separate but stay together until the moment of group fragmentation. We allow for all possible fragmentation patterns and calculate the population growth rate of each associated life cycle. Fragmentation modes that maximise growth rate comprise a restrictive set of patterns that include production of unicellular propagules and division into two similar size groups. Life cycles marked by single-cell bottlenecks maximise population growth rate under a wide range of conditions. This surprising result offers a new evolutionary explanation for the widespread occurrence of this mode of reproduction. All in all, our model provides a framework for exploring the adaptive significance of fragmentation modes and their associated life cycles.

  13. Fragmentation modes and the evolution of life cycles

    PubMed Central

    Rainey, Paul B.

    2017-01-01

    Reproduction is a defining feature of living systems. To reproduce, aggregates of biological units (e.g., multicellular organisms or colonial bacteria) must fragment into smaller parts. Fragmentation modes in nature range from binary fission in bacteria to collective-level fragmentation and the production of unicellular propagules in multicellular organisms. Despite this apparent ubiquity, the adaptive significance of fragmentation modes has received little attention. Here, we develop a model in which groups arise from the division of single cells that do not separate but stay together until the moment of group fragmentation. We allow for all possible fragmentation patterns and calculate the population growth rate of each associated life cycle. Fragmentation modes that maximise growth rate comprise a restrictive set of patterns that include production of unicellular propagules and division into two similar size groups. Life cycles marked by single-cell bottlenecks maximise population growth rate under a wide range of conditions. This surprising result offers a new evolutionary explanation for the widespread occurrence of this mode of reproduction. All in all, our model provides a framework for exploring the adaptive significance of fragmentation modes and their associated life cycles. PMID:29166656

  14. The evolution of the land plant life cycle.

    PubMed

    Niklas, Karl J; Kutschera, Ulrich

    2010-01-01

    The extant land plants are unique among the monophyletic clade of photosynthetic eukaryotes, which consists of the green algae (chlorophytes), the charophycean algae (charophytes), numerous groups of unicellular algae (prasinophytes) and the embryophytes, by possessing, firstly, a sexual life cycle characterized by an alternation between a haploid, gametophytic and a diploid, sporophytic multicellular generation; secondly, the formation of egg cells within multicellular structures called archegonia; and, thirdly, the retention of the zygote and diploid sporophyte embryo within the archegonium. We review the developmental, paleobotanical and molecular evidence indicating that: the embryophytes descended from a charophyte-like ancestor; this common ancestor had a life cycle with only a haploid multicellular generation; and the most ancient (c. 410 Myr old) land plants (e.g. Cooksonia, Rhynia and Zosterophyllum) had a dimorphic life cycle (i.e. their haploid and diploid generations were morphologically different). On the basis of these findings, we suggest that the multicellular reproductive structures of extant charophytes and embryophytes are developmentally homologous, and that those of the embryophytes evolved by virtue of the co-option and re-deployment of ancient algal homeodomain gene networks.

  15. Design study of long-life PWR using thorium cycle

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Subkhi, Moh. Nurul; Su'ud, Zaki; Waris, Abdul

    2012-06-06

    Design study of long-life Pressurized Water Reactor (PWR) using thorium cycle has been performed. Thorium cycle in general has higher conversion ratio in the thermal spectrum domain than uranium cycle. Cell calculation, Burn-up and multigroup diffusion calculation was performed by PIJ-CITATION-SRAC code using libraries based on JENDL 3.2. The neutronic analysis result of infinite cell calculation shows that {sup 231}Pa better than {sup 237}Np as burnable poisons in thorium fuel system. Thorium oxide system with 8%{sup 233}U enrichment and 7.6{approx} 8%{sup 231}Pa is the most suitable fuel for small-long life PWR core because it gives reactivity swing less than 1%{Delta}k/kmore » and longer burn up period (more than 20 year). By using this result, small long-life PWR core can be designed for long time operation with reduced excess reactivity as low as 0.53%{Delta}k/k and reduced power peaking during its operation.« less

  16. Life cycle assessment of asphalt pavement maintenance.

    DOT National Transportation Integrated Search

    2014-01-01

    This study aims at developing a life cycle assessment (LCA) model to quantify the impact of pavement preservation on energy consumption and greenhouse gas (GHG) emissions. The construction stage contains material, manufacture, transportation and plac...

  17. Life-cycle management: a long-term challenge.

    PubMed

    Newman, Chris

    2003-04-01

    With some electronics components being withdrawn after only two years, life-cycle management is becoming a key strategic issue for users and manufacturers of electromedical equipment. This article describes some approaches to tackling the challenge.

  18. Designing for the ISD Life Cycle.

    ERIC Educational Resources Information Center

    Wallace, Guy W.; Hybert, Peter R.; Smith, Kelly R.; Blecke, Brian D.

    2002-01-01

    Outlines the recent criticisms of traditional ISD (Instructional Systems Design) and discusses the implications that impact the life cycle costs of T&D (Training and Development) projects and their ROI (Return On Investment) potential. Describes a modified approach to ISD which mimics the modular approach of systems engineering design.…

  19. The TMIS life-cycle process document, revision A

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Technical and Management Information System (TMIS) Life-Cycle Process Document describes the processes that shall be followed in the definition, design, development, test, deployment, and operation of all TMIS products and data base applications. This document is a roll out of TMIS Standards Document (SSP 30546). The purpose of this document is to define the life cycle methodology that the developers of all products and data base applications and any subsequent modifications shall follow. Included in this methodology are descriptions of the tasks, deliverables, reviews, and approvals that are required before a product or data base application is accepted in the TMIS environment.

  20. Life-history habitat matching in invading non-native plant species

    USGS Publications Warehouse

    Stohlgren, T.J.; Crosier, C.; Chong, G.W.; Guenther, D.; Evangelista, P.

    2005-01-01

    We briefly reviewed the literature on habitat matching in invading non-native plant species. Then we hypothesized that the richness and cover of native annual and perennial plant species integrate complex local information of vegetation and soils that would help to predict invasion success by similarly adapted non-native plant species. We tested these ‘life-history habitat matching’ relationships in 603 0.1-ha plots, including 294 plots in Colorado, which were relatively high for the cover of native perennial plant species, and for 309 0.1-ha plots in southern Utah, which were relatively high in the cover of native annual plant species. We found strong positive relationships between the richness and foliar cover for both native and non-native species, whether they were annual or perennial species (0.34 > r2 < 0.53; P < 0.0001). We also found significant positive relationships between the cover of native annual species at a site and the richness (r2 = 0.13; P < 0.0001) and the foliar cover (r2 = 0.06; P < 0.0001) of non-native annual species. The proportion of non-native annual species in the flora of a plot also increased significantly with the foliar cover of native annual species. Conversely, the richness and cover of non-native annual species were significantly negatively associated with the foliar cover of native perennial species (r2 = 0.05 and 0.06, respectively; P < 0.0001). The cover of non-native annual or perennial species was not significantly correlated with soil texture variables, %N, or %C. We conclude that there may be a high degree of life-history habitat matching by non-native annual species in these study sites. Information on native annual and perennial species richness and cover may help characterize the complex soils, climate, and disturbance environment in which similarly adapted non-native plant species establish and gain foliar cover.

  1. A life cycle greenhouse gas inventory of a tree production system

    Treesearch

    Alissa Kendall; E. Gregory McPherson

    2012-01-01

    PurposeThis study provides a detailed, process-based life cycle greenhouse gas (GHG) inventory of an ornamental tree production system for urban forestry. The success of large-scale tree planting initiatives for climate protection depends on projects being net sinks for CO2 over their entire life cycle....

  2. Addressing software security and mitigations in the life cycle

    NASA Technical Reports Server (NTRS)

    Gilliam, David; Powell, John; Haugh, Eric; Bishop, Matt

    2003-01-01

    Traditionally, security is viewed as an organizational and Information Technology (IIJ systems function comprising of Firewalls, intrusion detection systems (IDS), system security settings and patches to the operating system (OS) and applications running on it. Until recently, little thought has been given to the importance of security as a formal approach in the software life cycle. The Jet Propulsion Laboratory has approached the problem through the development of an integrated formal Software Security Assessment Instrument (SSAI) with six foci for the software life cycle.

  3. Addressing software security and mitigations in the life cycle

    NASA Technical Reports Server (NTRS)

    Gilliam, David; Powell, John; Haugh, Eric; Bishop, Matt

    2004-01-01

    Traditionally, security is viewed as an organizational and Information Technology (IT) systems function comprising of firewalls, intrusion detection systems (IDS), system security settings and patches to the operating system (OS) and applications running on it. Until recently, little thought has been given to the importance of security as a formal approach in the software life cycle. The Jet Propulsion Laboratory has approached the problem through the development of an integrated formal Software Security Assessment Instrument (SSAI) with six foci for the software life cycle.

  4. Research on conceptual/innovative design for the life cycle

    NASA Technical Reports Server (NTRS)

    Cagan, Jonathan; Agogino, Alice M.

    1990-01-01

    The goal of this research is developing and integrating qualitative and quantitative methods for life cycle design. The definition of the problem includes formal computer-based methods limited to final detailing stages of design; CAD data bases do not capture design intent or design history; and life cycle issues were ignored during early stages of design. Viewgraphs outline research in conceptual design; the SYMON (SYmbolic MONotonicity analyzer) algorithm; multistart vector quantization optimization algorithm; intelligent manufacturing: IDES - Influence Diagram Architecture; and 1st PRINCE (FIRST PRINciple Computational Evaluator).

  5. Temperature fine-tunes Mediterranean Arabidopsis thaliana life-cycle phenology geographically.

    PubMed

    Marcer, A; Vidigal, D S; James, P M A; Fortin, M-J; Méndez-Vigo, B; Hilhorst, H W M; Bentsink, L; Alonso-Blanco, C; Picó, F X

    2018-01-01

    To understand how adaptive evolution in life-cycle phenology operates in plants, we need to unravel the effects of geographic variation in putative agents of natural selection on life-cycle phenology by considering all key developmental transitions and their co-variation patterns. We address this goal by quantifying the temperature-driven and geographically varying relationship between seed dormancy and flowering time in the annual Arabidopsis thaliana across the Iberian Peninsula. We used data on genetic variation in two major life-cycle traits, seed dormancy (DSDS50) and flowering time (FT), in a collection of 300 A. thaliana accessions from the Iberian Peninsula. The geographically varying relationship between life-cycle traits and minimum temperature, a major driver of variation in DSDS50 and FT, was explored with geographically weighted regressions (GWR). The environmentally varying correlation between DSDS50 and FT was analysed by means of sliding window analysis across a minimum temperature gradient. Maximum local adjustments between minimum temperature and life-cycle traits were obtained in the southwest Iberian Peninsula, an area with the highest minimum temperatures. In contrast, in off-southwest locations, the effects of minimum temperature on DSDS50 were rather constant across the region, whereas those of minimum temperature on FT were more variable, with peaks of strong local adjustments of GWR models in central and northwest Spain. Sliding window analysis identified a minimum temperature turning point in the relationship between DSDS50 and FT around a minimum temperature of 7.2 °C. Above this minimum temperature turning point, the variation in the FT/DSDS50 ratio became rapidly constrained and the negative correlation between FT and DSDS50 did not increase any further with increasing minimum temperatures. The southwest Iberian Peninsula emerges as an area where variation in life-cycle phenology appears to be restricted by the duration and severity

  6. 77 FR 38766 - Proposed Information Collection; Comment Request; International Client Life-Cycle Multi-Purpose...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ... Request; International Client Life-Cycle Multi-Purpose Forms AGENCY: International Trade Administration... aspects of an international organization's life-cycle with CS. CS is mandated by Congress to help U.S... trade events to U.S. organizations. The International Client Life-cycle Multi-Purpose Forms, previously...

  7. 7 CFR 2902.8 - Determining life cycle costs, environmental and health benefits, and performance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Determining life cycle costs, environmental and... DESIGNATING BIOBASED PRODUCTS FOR FEDERAL PROCUREMENT General § 2902.8 Determining life cycle costs, environmental and health benefits, and performance. (a) Providing information on life cycle costs and...

  8. Do mature forest birds prefer early-successional habitat during the post-fledging period?

    Treesearch

    Carlin C. Chandler; David I. King; Richard B. Chandler

    2012-01-01

    Recent studies have highlighted the importance of the post-fledging period to bird populations, suggesting that the importance of this portion of the life cycle is equal to or greater than the nesting period. Nevertheless, few studies have compared abundance of forest nesting species between mature forest and early-successional habitats while controlling for...

  9. Predicting and Mapping Potential Whooping Crane Stopover Habitat to Guide Site Selection for Wind Energy Projects

    EPA Science Inventory

    Migration is one of the most poorly understood components of a bird’s life cycle. For that reason, migratory stopover habitats are often not part of conservation planning and may be overlooked when planning new development projects. This project highlights and addresses an overl...

  10. Educated Parents, Educated Children: Toward a Multiple Life Cycles Education Policy

    ERIC Educational Resources Information Center

    Sticht, Thomas G.

    2010-01-01

    Given the important intergenerational effects of parents' education level on the achievement of their children, education policies should shift from a focus on one life cycle to a focus on "multiple life cycles". Such a policy would explicitly recognize that adults transfer their educational achievements to the achievement of their…

  11. Competitive Strategies of States: A Life-Cycle Perspective. EQW Working Papers.

    ERIC Educational Resources Information Center

    Flynn, Patricia M.

    This paper demonstrates that production life-cycle models provide a conceptual framework to analyze systematically the interrelationships between industrial and technological change and human resources. Section II presents the life-cycle model, focusing on its implications for the types and level of employment and skill requirements in an area.…

  12. Guidance on Data Quality Assessment for Life Cycle Inventory ...

    EPA Pesticide Factsheets

    Data quality within Life Cycle Assessment (LCA) is a significant issue for the future support and development of LCA as a decision support tool and its wider adoption within industry. In response to current data quality standards such as the ISO 14000 series, various entities within the LCA community have developed different methodologies to address and communicate the data quality of Life Cycle Inventory (LCI) data. Despite advances in this field, the LCA community is still plagued by the lack of reproducible data quality results and documentation. To address these issues, US EPA has created this guidance in order to further support reproducible life cycle inventory data quality results and to inform users of the proper application of the US EPA supported data quality system. The work for this report was begun in December 2014 and completed as of April 2016.The updated data quality system includes a novel approach to the pedigree matrix by addressing data quality at the flow and the process level. Flow level indicators address source reliability, temporal correlation, geographic correlation, technological correlation and data sampling methods. The process level indicators address the level of review the unit process has undergone and its completeness. This guidance is designed to be updatable as part of the LCA Research Center’s continuing commitment to data quality advancements. Life cycle assessment is increasingly being used as a tool to identify areas of

  13. Research on large equipment maintenance system in life cycle

    NASA Astrophysics Data System (ADS)

    Xu, Xiaowei; Wang, Hongxia; Liu, Zhenxing; Zhang, Nan

    2017-06-01

    In order to change the current disadvantages of traditional large equipment maintenance concept, this article plans to apply the technical method of prognostics and health management to optimize equipment maintenance strategy and develop large equipment maintenance system. Combined with the maintenance procedures of various phases in life cycle, it concluded the formulation methods of maintenance program and implement plans of maintenance work. In the meantime, it takes account into the example of the dredger power system of the Waterway Bureau to establish the auxiliary platform of ship maintenance system in life cycle.

  14. Research requirements to reduce civil helicopter life cycle cost

    NASA Technical Reports Server (NTRS)

    Blewitt, S. J.

    1978-01-01

    The problem of the high cost of helicopter development, production, operation, and maintenance is defined and the cost drivers are identified. Helicopter life cycle costs would decrease by about 17 percent if currently available technology were applied. With advanced technology, a reduction of about 30 percent in helicopter life cycle costs is projected. Technological and managerial deficiencies which contribute to high costs are examined, basic research and development projects which can reduce costs include methods for reduced fuel consumption; improved turbine engines; airframe and engine production methods; safety; rotor systems; and advanced transmission systems.

  15. Life cycle assessment of metals: a scientific synthesis.

    PubMed

    Nuss, Philip; Eckelman, Matthew J

    2014-01-01

    We have assembled extensive information on the cradle-to-gate environmental burdens of 63 metals in their major use forms, and illustrated the interconnectedness of metal production systems. Related cumulative energy use, global warming potential, human health implications and ecosystem damage are estimated by metal life cycle stage (i.e., mining, purification, and refining). For some elements, these are the first life cycle estimates of environmental impacts reported in the literature. We show that, if compared on a per kilogram basis, the platinum group metals and gold display the highest environmental burdens, while many of the major industrial metals (e.g., iron, manganese, titanium) are found at the lower end of the environmental impacts scale. If compared on the basis of their global annual production in 2008, iron and aluminum display the largest impacts, and thallium and tellurium the lowest. With the exception of a few metals, environmental impacts of the majority of elements are dominated by the purification and refining stages in which metals are transformed from a concentrate into their metallic form. Out of the 63 metals investigated, 42 metals are obtained as co-products in multi output processes. We test the sensitivity of varying allocation rationales, in which the environmental burden are allocated to the various metal and mineral products, on the overall results. Monte-Carlo simulation is applied to further investigate the stability of our results. This analysis is the most comprehensive life cycle comparison of metals to date and allows for the first time a complete bottom-up estimate of life cycle impacts of the metals and mining sector globally. We estimate global direct and indirect greenhouse gas emissions in 2008 at 3.4 Gt CO2-eq per year and primary energy use at 49 EJ per year (9.5% of global use), and report the shares for all metals to both impact categories.

  16. Restoring and rehabilitating sagebrush habitats

    USGS Publications Warehouse

    Pyke, David A.; Knick, S.T.; Connelly, J.W.

    2011-01-01

    Less than half of the original habitat of the Greater Sage-Grouse (Centrocercus uropha-sianus) currently exists. Some has been perma-nently lost to farms and urban areas, but the remaining varies in condition from high quality to no longer adequate. Restoration of sagebrush (Artemisia spp.) grassland ecosystems may be pos-sible for resilient lands. However, Greater Sage-Grouse require a wide variety of habitats over large areas to complete their life cycle. Effective restoration will require a regional approach for prioritizing and identifying appropriate options across the landscape. A landscape triage method is recommended for prioritizing lands for restora-tion. Spatial models can indicate where to protect and connect intact quality habitat with other simi-lar habitat via restoration. The ecological site con-cept of land classification is recommended for characterizing potential habitat across the region along with their accompanying state and transi-tion models of plant community dynamics. These models assist in identifying if passive, manage-ment-based or active, vegetation manipulation?based restoration might accomplish the goals of improved Greater Sage-Grouse habitat. A series of guidelines help formulate questions that manag-ers might consider when developing restoration plans: (1) site prioritization through a landscape triage; (2) soil verification and the implications of soil features on plant establishment success; (3) a comparison of the existing plant community to the potential for the site using ecological site descriptions; (4) a determination of the current successional status of the site using state and transition models to aid in predicting if passive or active restoration is necessary; and (5) implemen-tation of post-treatment monitoring to evaluate restoration effectiveness and post-treatment man-agement implications to restoration success.

  17. Anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.

    PubMed

    Kweka, Eliningaya J; Zhou, Guofa; Munga, Stephen; Lee, Ming-Chieh; Atieli, Harrysone E; Nyindo, Mramba; Githeko, Andrew K; Yan, Guiyun

    2012-01-01

    Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya. A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60%) and An.arabiensis (18.34%), the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024) and An. arabiensis (P = 0.002) larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001), grass cover (P≤0.001), while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001). The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001) when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002). When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines. These findings suggest that implementation of effective larval control programme should be targeted with larval habitats

  18. Life Cycle Energy Assessment of a Multi-storey Residential Building

    NASA Astrophysics Data System (ADS)

    Mehta, Sourabh; Chandur, Arjun; Palaniappan, Sivakumar

    2017-06-01

    This study presents the findings of life cycle energy assessment of two multi-storey residential buildings. These buildings consist of a total of 60 homes. The usable floor area is 43.14 m2 (463.36 ft2) per home. A detailed estimation of embodied energy is carried out by considering the use of materials during building construction. Major contributors of embodied energy are found to be steel, cement and aluminum. Monthly building operation energy was assessed using a total of 2520 data samples corresponding to 3 years of building operation. Analysis of a base case scenario, with 50 years of service life and average monthly operation energy, indicates that the embodied energy and the operation energy account for 16 and 84% of the life cycle energy respectively. Sensitivity analysis is carried out to study the influence of service life and operation energy on the relative contribution of embodied energy and operation energy. It is found that the embodied energy represents as high as 31% of the life cycle energy depending upon the variation in the operation energy and the service life. Hence, strategies towards sustainable building construction should also focus on reducing the embodied energy in the design and construction phases in addition to operation energy.

  19. Geothermal Life Cycle Calculator

    DOE Data Explorer

    Sullivan, John

    2014-03-11

    This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.

  20. The genetic covariance between life cycle stages separated by metamorphosis.

    PubMed

    Aguirre, J David; Blows, Mark W; Marshall, Dustin J

    2014-08-07

    Metamorphosis is common in animals, yet the genetic associations between life cycle stages are poorly understood. Given the radical changes that occur at metamorphosis, selection may differ before and after metamorphosis, and the extent that genetic associations between pre- and post-metamorphic traits constrain evolutionary change is a subject of considerable interest. In some instances, metamorphosis may allow the genetic decoupling of life cycle stages, whereas in others, metamorphosis could allow complementary responses to selection across the life cycle. Using a diallel breeding design, we measured viability at four ontogenetic stages (embryo, larval, juvenile and adult viability), in the ascidian Ciona intestinalis and examined the orientation of additive genetic variation with respect to the metamorphic boundary. We found support for one eigenvector of G: (gobsmax ), which contrasted larval viability against embryo viability and juvenile viability. Target matrix rotation confirmed that while gobsmax shows genetic associations can extend beyond metamorphosis, there is still considerable scope for decoupled phenotypic evolution. Therefore, although genetic associations across metamorphosis could limit that range of phenotypes that are attainable, traits on either side of the metamorphic boundary are capable of some independent evolutionary change in response to the divergent conditions encountered during each life cycle stage. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  1. The genetic covariance between life cycle stages separated by metamorphosis

    PubMed Central

    Aguirre, J. David; Blows, Mark W.; Marshall, Dustin J.

    2014-01-01

    Metamorphosis is common in animals, yet the genetic associations between life cycle stages are poorly understood. Given the radical changes that occur at metamorphosis, selection may differ before and after metamorphosis, and the extent that genetic associations between pre- and post-metamorphic traits constrain evolutionary change is a subject of considerable interest. In some instances, metamorphosis may allow the genetic decoupling of life cycle stages, whereas in others, metamorphosis could allow complementary responses to selection across the life cycle. Using a diallel breeding design, we measured viability at four ontogenetic stages (embryo, larval, juvenile and adult viability), in the ascidian Ciona intestinalis and examined the orientation of additive genetic variation with respect to the metamorphic boundary. We found support for one eigenvector of G (gobsmax), which contrasted larval viability against embryo viability and juvenile viability. Target matrix rotation confirmed that while gobsmax shows genetic associations can extend beyond metamorphosis, there is still considerable scope for decoupled phenotypic evolution. Therefore, although genetic associations across metamorphosis could limit that range of phenotypes that are attainable, traits on either side of the metamorphic boundary are capable of some independent evolutionary change in response to the divergent conditions encountered during each life cycle stage. PMID:24966319

  2. Environmental control and life support system selection for the first Lunar outpost habitat

    NASA Technical Reports Server (NTRS)

    Adams, Alan

    1993-01-01

    The planning for and feasibility study of an early human return mission to the lunar surface has been undertaken. The First Lunar Outpost (FLO) Mission philosophy is to use existing or near-term technology to achieve a human landing on the lunar surface in the year 2000. To support the crew the lunar habitat for the FLO mission incorporates an environmental control/life support system (ECLSS) design which meets the mission requirements and balances fixed mass and consumable mass. This tradeoff becomes one of regenerable life support systems versus open-loop systems.

  3. Life cycle thinking in impact assessment—Current practice and LCA gains

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bidstrup, Morten, E-mail: Bidstrup@plan.aau.dk

    It has been advocated that life cycle thinking (LCT) should be applied in impact assessment (IA) to a greater extent, since some development proposals pose a risk of significant impacts throughout the interconnected activities of product systems. Multiple authors have proposed the usage of life cycle assessment (LCA) for such analytical advancement, but little to no research on this tool application has been founded in IA practice so far. The aim of this article is to elaborate further on the gains assigned to application of LCA. The research builds on a review of 85 Danish IA reports, which were analysedmore » for analytical appropriateness and application of LCT. Through a focus on the non-technical summary, the conclusion and the use of specific search words, passages containing LCT were searched for in each IA report. These passages were then analysed with a generic framework. The results reveal that LCT is appropriate for most of the IAs, but that LCA is rarely applied to provide such a perspective. Without LCA, the IAs show mixed performance in regard to LCT. Most IAs do consider the product provision of development proposals, but they rarely relate impacts to this function explicitly. Many IAs do consider downstream impacts, but assessments of upstream, distant impacts are generally absent. It is concluded that multiple analytical gains can be attributed to greater application of LCA in IA practice, though some level of LCT already exists. - Highlights: • Life cycle thinking is appropriate across the types and topics of impact assessment. • Yet, life cycle assessment is rarely used for adding such perspective. • Impact assessment practice does apply some degree of life cycle thinking. • However, application of life cycle assessment could bring analytical gains.« less

  4. Profiling crop pollinators: life history traits predict habitat use and crop visitation by Mediterranean wild bees.

    PubMed

    Pisanty, Gideon; Mandelik, Yael

    2015-04-01

    Wild pollinators, bees in particular, may greatly contribute to crop pollination and provide a safety net against declines in commercial pollinators. However, the identity, life history traits, and environmental sensitivities of main crop pollinator species.have received limited attention. These are crucial for predicting pollination services of different communities and for developing management practices that enhance crop pollinators. We sampled wild bees in three crop systems (almond, confection sunflower, and seed watermelon) in a mosaic Israeli Mediterranean landscape. Bees were sampled in field/orchard edges and interiors, and in seminatural scrub surrounding the fields/orchards. We also analyzed land cover at 50-2500 m radii around fields/orchards. We used this data to distinguish crop from non-crop pollinators based on a set of life history traits (nesting, lecty, sociality, body size) linked to habitat preference and crop visitation. Bee abundance and species richness decreased from the surrounding seminatural habitat to the field/orchard interior, especially across the seminatural habitat-field edge ecotone. Thus, although rich bee communities were found near fields, only small fractions crossed the ecotone and visited crop flowers in substantial numbers. The bee assemblage in agricultural fields/orchards and on crop flowers was dominated by ground-nesting bees of the tribe Halictini, which tend to nest within fields. Bees' habitat preferences were determined mainly by nesting guild, whereas crop visitation was determined mainly by sociality. Lecty and body size also affected both measures. The percentage of surrounding seminatural habitat at 250-2500 m radii had a positive effect on wild bee diversity in field edges, for all bee guilds, while at 50-100 m radii, only aboveground nesters were positively affected. In sum, we found that crop and non-crop pollinators are distinguished by behavioral and morphological traits. Hence, analysis of life

  5. A Robust Hybrid Zn-Battery with Ultralong Cycle Life.

    PubMed

    Li, Bing; Quan, Junye; Loh, Adeline; Chai, Jianwei; Chen, Ye; Tan, Chaoliang; Ge, Xiaoming; Hor, T S Andy; Liu, Zhaolin; Zhang, Hua; Zong, Yun

    2017-01-11

    Advanced batteries with long cycle life and capable of harnessing more energies from multiple electrochemical reactions are both fundamentally interesting and practically attractive. Herein, we report a robust hybrid zinc-battery that makes use of transition-metal-based redox reaction (M-O-OH → M-O, M = Ni and Co) and oxygen reduction reaction (ORR) to deliver more electrochemical energies of comparably higher voltage with much longer cycle life. The hybrid battery was constructed using an integrated electrode of NiCo 2 O 4 nanowire arrays grown on carbon-coated nickel foam, coupled with a zinc plate anode in alkaline electrolyte. Benefitted from the M-O/M-O-OH redox reactions and rich ORR active sites in NiCo 2 O 4 , the battery has concurrently exhibited high working voltage (by M-O-OH → M-O) and high energy density (by ORR). The good oxygen evolution reaction (OER) activity of the electrode and the reversible M-O ↔ M-O-OH reactions also enabled smooth recharging of the batteries, leading to excellent cycling stabilities. Impressively, the hybrid batteries maintained highly stable charge-discharge voltage profile under various testing conditions, for example, almost no change was observed over 5000 cycles at a current density of 5 mA cm -2 after some initial stabilization. With merits of higher working voltage, high energy density, and ultralong cycle life, such hybrid batteries promise high potential for practical applications.

  6. LIFE CYCLE IMPACT ASSESSMENT - A GLOBAL PERSPECTIVE

    EPA Science Inventory

    Research within the field of life cycle impact assessment has greatly improved since the work of Heijungs and Guinee in 1992. Methodologies are currently available to address specific locations within North America, Europe and Asia. Internationally researchers are working togethe...

  7. LIFE CYCLE ASSESSMENT OF GASOLINE BLENDING OPTIONS

    EPA Science Inventory

    A life cycle assessment has been done to compare the potential environmental impacts of various gasoline blends that meet octane and vapour pressure specifications. The main blending components of alkylate, cracked gasoline and reformate have different octane and vapour pressure...

  8. LIFE CYCLE ASSESSMENT: INVENTORY GUIDELINES AND PRINCIPLES

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) is describing the process, the underlying data, and the Inherent assumptions Involved in conducting the Inventory component of a life-cycle assessment (LCA) In order to facilitate understanding by potential users. This Inventory...

  9. Sampling and monitoring for the mine life cycle

    USGS Publications Warehouse

    McLemore, Virginia T.; Smith, Kathleen S.; Russell, Carol C.

    2014-01-01

    Sampling and Monitoring for the Mine Life Cycle provides an overview of sampling for environmental purposes and monitoring of environmentally relevant variables at mining sites. It focuses on environmental sampling and monitoring of surface water, and also considers groundwater, process water streams, rock, soil, and other media including air and biological organisms. The handbook includes an appendix of technical summaries written by subject-matter experts that describe field measurements, collection methods, and analytical techniques and procedures relevant to environmental sampling and monitoring.The sixth of a series of handbooks on technologies for management of metal mine and metallurgical process drainage, this handbook supplements and enhances current literature and provides an awareness of the critical components and complexities involved in environmental sampling and monitoring at the mine site. It differs from most information sources by providing an approach to address all types of mining influenced water and other sampling media throughout the mine life cycle.Sampling and Monitoring for the Mine Life Cycle is organized into a main text and six appendices that are an integral part of the handbook. Sidebars and illustrations are included to provide additional detail about important concepts, to present examples and brief case studies, and to suggest resources for further information. Extensive references are included.

  10. Cycle life performance of rechargeable lithium ion batteries and mathematical modeling

    NASA Astrophysics Data System (ADS)

    Ning, Gang

    Capacity fade of commercial Sony US 18650 Li-ion batteries cycled at high discharge rates was studied at ambient temperature. Battery cycled at the highest discharge rate (3 C) shows the largest internal resistance increase of 27.7% relative to the resistance of fresh battery. It's been observed anode carbon loses 10.6% of its capability to intercalate or deintercalate Li+ after it was subjected to 300 cycles at discharge rate of 3 C. This loss dominates capacity fade of full battery. A mechanism considering continuous parasitic reaction at anode/electrolyte interface and film thickening has been proposed. First principles based charge-discharge models to simulate cycle life behavior of rechargeable Li-ion batteries have been developed. In the generalized model, transport in both electrolyte phase and solid phase were simultaneously taken into account. Under mild charge-discharge condition, transport of lithium in the electrolyte phase has been neglected in the simplified model. Both models are based on loss of the active lithium ions due to the electrochemical parasitic reaction at anode/electrolyte interface and on rise of the anode film resistance. The effect of parameters such as depth of discharge (DOD), end of charge voltage (EOCV) and overvoltage of the parasitic reaction on the cycle life behavior of a battery has been analyzed. The experimental results obtained at a charge rate of 1 C, discharge rate of 0.5 C, EOCV of 4.0 V and DOD of 0.4 have been used to validate cycle life models. Good agreement between the simulations and the experiments has been achieved up to 1968 cycles with both models. Simulation of cycle life of battery under multiple cycling regimes has also been demonstrated.

  11. Life-cycle analysis of shale gas and natural gas.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clark, C.E.; Han, J.; Burnham, A.

    2012-01-27

    The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. Using the current state of knowledge of the recovery, processing, and distribution of shale gas and conventional natural gas, we have estimated up-to-date, life-cycle greenhouse gas emissions. In addition, we have developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps - such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings - that need to be addressed further. Our base case results showmore » that shale gas life-cycle emissions are 6% lower than those of conventional natural gas. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty regarding whether shale gas emissions are indeed lower than conventional gas emissions. This life-cycle analysis provides insight into the critical stages in the natural gas industry where emissions occur and where opportunities exist to reduce the greenhouse gas footprint of natural gas.« less

  12. Managing Environmental Flows for Impounded Rivers in Semi-Arid Regions- A Habitat Suitability Index (HSI) Approach for the Assessment of River Habitat for Salmonid Populations

    NASA Astrophysics Data System (ADS)

    Pai, H.; Sivakumaran, K.; Villamizar, S. R.; Flanagan, J.; Guo, Q.; Harmon, T. C.

    2013-12-01

    Balancing ecosystem health in water-scarce, agriculturally dominated river basins remains a challenge. In dry water years, maintaining conditions for restored and sustained indigenous fish populations (a frequently used indicator for ecosystem health) is particularly challenging. Competing human demands include urban and agricultural water supplies, hydropower, and flood control. In many semi-arid regions, increasing drought intensity and frequency under future climate scenarios will combine with population increases to water scarcity. The goal of this work is to better understand how reservoir releases affect fish habitat and overall river aquatic ecosystem quality. Models integrating a diverse array of physical and biological processes and system state are used to forecast the river ecosystem response to changing drivers. We propose a distributed parameter-based Habitat Suitability Index (HSI) approach for assessing fish habitat quality. Our river ecosystem HSI maps are based on a combination of the following: (1) In situ data describing stream flow and water quality conditions; (2) Spatial observations, including surveyed cross-sections, aerial imagery and digital elevation maps (DEM) of the river and its riparian corridor; and (3) Simulated spatially distributed water depths, flow velocities, and temperatures estimated from 1D and 2D river flow and temperature models (HEC-RAS and CE-QUAL-W2, respectively). With respect to (2), image processing schemes are used to classify and map key habitat features, namely riparian edge and shallow underwater vegetation. HSI maps can be modified temporally to address specific life cycle requirements of indicator fish species. Results are presented for several reaches associated with the San Joaquin River Restoration Project, focusing on several components of the Chinook salmon life cycle. HSI maps and interpretations are presented in the context of a range of prescribed reservoir release hydrographs linked to California water

  13. Systematic Review of Life Cycle Greenhouse Gas Emissions from Geothermal Electricity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eberle, Annika; Heath, Garvin A.; Carpenter Petri, Alberta C.

    The primary goal of this work was to assess the magnitude and variability of published life cycle greenhouse gas (GHG) emission estimates for three types of geothermal electricity generation technologies: enhanced geothermal systems (EGS) binary, hydrothermal (HT) flash, and HT binary. These technologies were chosen to align the results of this report with technologies modeled in National Renewable Energy Laboratory's (NREL's) Regional Energy Deployment Systems (ReEDs) model. Although we did gather and screen life cycle assessment (LCA) literature on hybrid systems, dry steam, and two geothermal heating technologies, we did not analyze published GHG emission estimates for these technologies. Inmore » our systematic literature review of the LCA literature, we screened studies in two stages based on a variety of criteria adapted from NREL's Life Cycle Assessment (LCA) Harmonization study (Heath and Mann 2012). Of the more than 180 geothermal studies identified, only 29 successfully passed both screening stages and only 26 of these included estimates of life cycle GHG emissions. We found that the median estimate of life cycle GHG emissions (in grams of carbon dioxide equivalent per kilowatt-hour generated [g CO2eq/kWh]) reported by these studies are 32.0, 47.0, and 11.3 for EGS binary, HT flash, and HT binary, respectively (Figure ES-1). We also found that the total life cycle GHG emissions are dominated by different stages of the life cycle for different technologies. For example, the GHG emissions from HT flash plants are dominated by the operations phase owing to the flash cycle being open loop whereby carbon dioxide entrained in the geothermal fluids is released to the atmosphere. This is in contrast to binary plants (using either EGS or HT resources), whose GHG emissions predominantly originate in the construction phase, owing to its closed-loop process design. Finally, by comparing this review's literature-derived range of HT flash GHG emissions to data from

  14. Earth Without Life: A Systems Model of a Global Abiotic Nitrogen Cycle

    NASA Astrophysics Data System (ADS)

    Laneuville, M.; Kameya, M.; Cleaves, H. J.

    2017-07-01

    N is the major component of the atmosphere and plays important roles in biochemistry. Presently, the surface N-cycle is dominated by biology. However, before the origin of life, abiotic N-cycling would have set the stage for the origin of life.

  15. Low-Earth-Orbit (LEO) Life Cycle Evaluation of Nickel-Zinc Batteries

    NASA Technical Reports Server (NTRS)

    Coates, D.; Ferreira, E.; Nyce, M.; Charkey, A.

    1997-01-01

    The conclusion of the Low-Earth-Orbit (LEO) life cycle evaluation of nickel-zinc batteries are: that composite nickel electrode provide excellent performance at a reduced weight and lower cost; calcium / zinc electrode minimizes shape change; unioptimized cell designs yield 60 Wh/kg; nickel-zinc delivers 600 cycles at 80% DOD; long cycle life obtainable at low DOD; high rate capability power density; long-term failure mechanism is stack dry; and anomalous overcharge (1120%) greatly affected cell performance but did not induce failure and was recoverable.

  16. Performance improvement: an active life cycle product management

    NASA Astrophysics Data System (ADS)

    Cucchiella, Federica; Gastaldi, Massimo; Lenny Koh, S. C.

    2010-03-01

    The management of the supply chain has gained importance in many manufacturing firms. Operational flexibility can be considered a crucial weapon to increase competitiveness in a turbulent marketplace. It reflects the ability of a firm to properly and rapidly respond to a variable and dynamic environment. For the firm operating in a fashion sector, the management of the supply chain is even more complex because the product life cycle is shorter than that of the firm operating in a non-fashion sector. The increase of firm flexibility level can be reached through the application of the real option theory inside the firm network. In fact, real option may increase the project value by allowing managers to more efficiently direct the production. The real option application usually analysed in literature does not take into account that the demands of products are well-defined by the product life cycle. Working on a fashion sector, the life cycle pattern is even more relevant because of an expected demand that grows according to a constant rate that does not capture the demand dynamics of the underlying fashion goods. Thus, the primary research objective of this article is to develop a model useful for the management of investments in a supply chain operating in a fashion sector where the system complexity is increased by the low level of unpredictability and stability that is proper of the mood phenomenon. Moreover, unlike the traditional model, a real option framework is presented here that considers fashion product characterised by uncertain stages of the production cycle.

  17. Life cycle assessment of mobile phone housing.

    PubMed

    Yang, Jian-xin; Wang, Ru-song; Fu, Hao; Liu, Jing-ru

    2004-01-01

    The life cycle assessment of the mobile phone housing in Motorola(China) Electronics Ltd. was carried out, in which materials flows and environmental emissions based on a basic production scheme were analyzed and assessed. In the manufacturing stage, such primary processes as polycarbonate molding and surface painting are included, whereas different surface finishing technologies like normal painting, electroplate, IMD and VDM etc. were assessed. The results showed that housing decoration plays a significant role within the housing life cycle. The most significant environmental impact from housing production is the photochemical ozone formation potential. Environmental impacts of different decoration techniques varied widely, for example, the electroplating technique is more environmentally friendly than VDM. VDM consumes much more energy and raw material. In addition, the results of two alternative scenarios of dematerialization showed that material flow analysis and assessment is very important and valuable in selecting an environmentally friendly process.

  18. Developing a dynamic life cycle greenhouse gas emission inventory for wood construction for two different end-of-life scenarios

    Treesearch

    Richard D. Bergman; James Salazar; Scott Bowe

    2012-01-01

    Static life cycle assessment does not fully describe the carbon footprint of construction wood because of carbon changes in the forest and product pools over time. This study developed a dynamic greenhouse gas (GHG) inventory approach using US Forest Service and life-cycle data to estimate GHG emissions on construction wood for two different end-of-life scenarios....

  19. Life cycle, individual thrift, and the wealth of nations.

    PubMed

    Modigliani, F

    1986-11-07

    One theory of the determinants of individual and national thrift has come to be known as the life cycle hypothesis of saving. The state of the art on the eve of the formulation of the hypothesis some 30 years ago is reviewed. Then the theoretical foundations of the model in its original formulation and later amendment are set forth, calling attention to various implications, some distinctive to it and some counterintuitive. A number of crucial empirical tests, both at the individual and the aggregate level, are presented as well as some applications of the life cycle hypothesis of saving to current policy issues.

  20. The data life cycle applied to our own data.

    PubMed

    Goben, Abigail; Raszewski, Rebecca

    2015-01-01

    Increased demand for data-driven decision making is driving the need for librarians to be facile with the data life cycle. This case study follows the migration of reference desk statistics from handwritten to digital format. This shift presented two opportunities: first, the availability of a nonsensitive data set to improve the librarians' understanding of data-management and statistical analysis skills, and second, the use of analytics to directly inform staffing decisions and departmental strategic goals. By working through each step of the data life cycle, library faculty explored data gathering, storage, sharing, and analysis questions.

  1. Product-related research: how research can contribute to successful life-cycle management.

    PubMed

    Sandner, Peter; Ziegelbauer, Karl

    2008-05-01

    Declining productivity with decreasing new molecular entity output combined with increased R&D spending is one of the key challenges for the entire pharmaceutical industry. In order to offset decreasing new molecular entity output, life-cycle management activities for established drugs become more and more important to maintain or even expand clinical indication and market opportunities. Life-cycle management covers a whole range of activities from strategic pricing to a next generation product launch. In this communication, we review how research organizations can contribute to successful life-cycle management strategies using phosphodiesterase 5 inhibitors as an example.

  2. Recurrent bottlenecks in the malaria life cycle obscure signals of positive selection.

    PubMed

    Chang, Hsiao-Han; Hartl, Daniel L

    2015-02-01

    Detecting signals of selection in the genome of malaria parasites is a key to identify targets for drug and vaccine development. Malaria parasites have a unique life cycle alternating between vector and host organism with a population bottleneck at each transition. These recurrent bottlenecks could influence the patterns of genetic diversity and the power of existing population genetic tools to identify sites under positive selection. We therefore simulated the site-frequency spectrum of a beneficial mutant allele through time under the malaria life cycle. We investigated the power of current population genetic methods to detect positive selection based on the site-frequency spectrum as well as temporal changes in allele frequency. We found that a within-host selective advantage is difficult to detect using these methods. Although a between-host transmission advantage could be detected, the power is decreased when compared with the classical Wright-Fisher (WF) population model. Using an adjusted null site-frequency spectrum that takes the malaria life cycle into account, the power of tests based on the site-frequency spectrum to detect positive selection is greatly improved. Our study demonstrates the importance of considering the life cycle in genetic analysis, especially in parasites with complex life cycles.

  3. Impact of Life-Cycle Stage and Gender on the Ability to Balance Work and Family Responsibilities.

    ERIC Educational Resources Information Center

    Higgins, Christopher; And Others

    1994-01-01

    Examined impact of gender and life-cycle stage on three components of work-family conflict using sample of 3,616 respondents. For men, levels of work-family conflict were moderately lower in each successive life-cycle stage. For women, levels were similar in two early life-cycle stages but were significantly lower in later life-cycle stage.…

  4. Incorporating exposure science into life-cycle assessment

    EPA Science Inventory

    Life-cycle assessment (LCA) is used to estimate the potential for environmental damage that may be caused by a product or process, ideally before the product or process begins. LCA includes all of the steps from extracting natural resources through manufacturing through product u...

  5. Life Cycle Assessment Perspectives on Delivering an Infant in the US

    PubMed Central

    Campion, Nicole; Thiel, Cassandra L.; DeBlois, Justin; Woods, Noe C.; Landis, Amy E.; Bilec, Melissa M.

    2012-01-01

    This study introduces life cycle assessment as a tool to analyze one aspect of sustainability in healthcare: the birth of a baby. The process life cycle assessment case study presented evaluates two common procedures in a hospital, a cesarean section and a vaginal birth. This case study was conducted at Magee-Womens Hospital of the University of Pittsburgh Medical Center, which delivers over 10,000 infants per year. The results show that heating, ventilation, and air conditioning (HVAC), waste disposal, and the production of the disposable custom packs comprise a large percentage of the environmental impacts. Applying the life cycle assessment tool to medical procedures allows hospital decision makers to target and guide efforts to reduce the environmental impacts of healthcare procedures. PMID:22482785

  6. [Update on the epidemiology of hydatidosis. Hydatid echinococci: species; life cycles; epidemiologic consequences].

    PubMed

    Euzéby, J

    1990-05-01

    Human hydatidosis results from infestation by two species of Echinococcus. (1) E. vogeli, the life-cycle of which occurs in amazonian forests and involves wild canidae and cuniculidae. (2) E. granulosus, which includes two geographical groups: (a) Northern group, with two sub-species E. g borelis and E. g. canadensis, the life-cycle of which is sylvatic and that are agents of a pulmonary hydatidosis which may affect Man. (b) "European" (actually cosmopolitan) form, with two sub-species: (1) E. q. equinus (equine strain) occurring between dogs and horses and unable to infect Man; (2) E. g. granulosus, with several strains and clones according to the species of their intermediate hosts and which are the agents of synanthropic or sylvatic life-cycles. Man may enter into some of these life cycles, but not into all of them: ovine strains, chiefly, but pig and camel strains also, have a zoonotic incidence. From these data, the author emphasizes the epidemiological features of human hydatidosis, which over-runs the classical rural one, resulting from the drog-sheep life-cycle.

  7. 77 FR 38582 - Proposed Information Collection; Comment Request; Domestic Client Life-Cycle Multi-Purpose Forms

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-28

    ... Request; Domestic Client Life-Cycle Multi-Purpose Forms AGENCY: International Trade Administration. ACTION... life-cycle with CS. CS is mandated by Congress to help U.S. organizations, particularly small and... Client Life-cycle Multi-Purpose Forms, previously titled Export Information Services Order Forms, are...

  8. Long cycle life rechargeable lithium batteries

    NASA Technical Reports Server (NTRS)

    Pasquariello, D. M.; Willstaedt, E. B.; Abraham, K. M.

    1992-01-01

    Cycle life and safety of delta-LiAl/TiS2 cells were evaluated using laboratory and AA-size cells. Analysis of the alloys (which contained 60, 70, 80, or 85 wt-pct. lithium and are designated 60 LiAl etc.) showed them to contain a mixture of elemental Li and Al4Li9. Cycling efficiencies correlated with the amount of free lithium in the anode. Using an electrolyte with the composition 48 v/o THF:48 v/o 2-MeTHF:4 v/o 2-MeF/LiAsF6(1.5M), a 70 LiAl/TiS2 laboratory cell yielded a cycling efficiency of 96.4 pct. when cycled at a 100 pct. discharge depth which compares well with Li anode cycling efficiencies of 96 to 97.5 pct. obtained previously in this electrolyte. The highest cycling efficiency of any delta-LiAl/TiS2 laboratory cell was 96.7 pct. when the 60 LiAl alloy was used with the 35 v/o PC:35 v/o EC:30 v/o triglyme/LiAsF6(1.0M) electrolyte. The 70 LiAl alloy was selected for further testing in AA cells since it was malleable for the fabrication of spirally wound electrodes, and its overall cycling performance was sufficiently good. AA-size 70 LiAl/TiS2 cells appear to have capacity/rate properties similar to those for identical Li/TiS2 cells. The use of the delta-LiAl alloy anodes does not appear to offer any safety advantage when cycled cells are shorted or heated.

  9. Life Cycle Assessment of Completely Recyclable Concrete.

    PubMed

    De Schepper, Mieke; Van den Heede, Philip; Van Driessche, Isabel; De Belie, Nele

    2014-08-21

    Since the construction sector uses 50% of the Earth's raw materials and produces 50% of its waste, the development of more durable and sustainable building materials is crucial. Today, Construction and Demolition Waste (CDW) is mainly used in low level applications, namely as unbound material for foundations, e.g., in road construction. Mineral demolition waste can be recycled as crushed aggregates for concrete, but these reduce the compressive strength and affect the workability due to higher values of water absorption. To advance the use of concrete rubble, Completely Recyclable Concrete (CRC) is designed for reincarnation within the cement production, following the Cradle-to-Cradle (C2C) principle. By the design, CRC becomes a resource for cement production because the chemical composition of CRC will be similar to that of cement raw materials. If CRC is used on a regular basis, a closed concrete-cement-concrete material cycle will arise, which is completely different from the current life cycle of traditional concrete. Within the research towards this CRC it is important to quantify the benefit for the environment and Life Cycle Assessment (LCA) needs to be performed, of which the results are presented in a this paper. It was observed that CRC could significantly reduce the global warming potential of concrete.

  10. Life Cycle Assessment of Completely Recyclable Concrete

    PubMed Central

    De Schepper, Mieke; Van den Heede, Philip; Van Driessche, Isabel; De Belie, Nele

    2014-01-01

    Since the construction sector uses 50% of the Earth’s raw materials and produces 50% of its waste, the development of more durable and sustainable building materials is crucial. Today, Construction and Demolition Waste (CDW) is mainly used in low level applications, namely as unbound material for foundations, e.g., in road construction. Mineral demolition waste can be recycled as crushed aggregates for concrete, but these reduce the compressive strength and affect the workability due to higher values of water absorption. To advance the use of concrete rubble, Completely Recyclable Concrete (CRC) is designed for reincarnation within the cement production, following the Cradle-to-Cradle (C2C) principle. By the design, CRC becomes a resource for cement production because the chemical composition of CRC will be similar to that of cement raw materials. If CRC is used on a regular basis, a closed concrete-cement-concrete material cycle will arise, which is completely different from the current life cycle of traditional concrete. Within the research towards this CRC it is important to quantify the benefit for the environment and Life Cycle Assessment (LCA) needs to be performed, of which the results are presented in a this paper. It was observed that CRC could significantly reduce the global warming potential of concrete. PMID:28788174

  11. SCREENING LIFE CYCLE ASSESSMENT OF GASOLINE ADDITIVES

    EPA Science Inventory

    The EPA's ORD is conducting a screening of Life Cycle Assessment (LCA) of selected automotive fuel (i.e., gasoline) systems. Although no specific guidelines exist on how to conduct such a streamlined approach, the basic idea is to use a mix of qualitative and quantitative generi...

  12. Failure of engineering artifacts: a life cycle approach.

    PubMed

    Del Frate, Luca

    2013-09-01

    Failure is a central notion both in ethics of engineering and in engineering practice. Engineers devote considerable resources to assure their products will not fail and considerable progress has been made in the development of tools and methods for understanding and avoiding failure. Engineering ethics, on the other hand, is concerned with the moral and social aspects related to the causes and consequences of technological failures. But what is meant by failure, and what does it mean that a failure has occurred? The subject of this paper is how engineers use and define this notion. Although a traditional definition of failure can be identified that is shared by a large part of the engineering community, the literature shows that engineers are willing to consider as failures also events and circumstance that are at odds with this traditional definition. These cases violate one or more of three assumptions made by the traditional approach to failure. An alternative approach, inspired by the notion of product life cycle, is proposed which dispenses with these assumptions. Besides being able to address the traditional cases of failure, it can deal successfully with the problematic cases. The adoption of a life cycle perspective allows the introduction of a clearer notion of failure and allows a classification of failure phenomena that takes into account the roles of stakeholders involved in the various stages of a product life cycle.

  13. A Methodology for Integrated, Multiregional Life Cycle Assessment Scenarios under Large-Scale Technological Change.

    PubMed

    Gibon, Thomas; Wood, Richard; Arvesen, Anders; Bergesen, Joseph D; Suh, Sangwon; Hertwich, Edgar G

    2015-09-15

    Climate change mitigation demands large-scale technological change on a global level and, if successfully implemented, will significantly affect how products and services are produced and consumed. In order to anticipate the life cycle environmental impacts of products under climate mitigation scenarios, we present the modeling framework of an integrated hybrid life cycle assessment model covering nine world regions. Life cycle assessment databases and multiregional input-output tables are adapted using forecasted changes in technology and resources up to 2050 under a 2 °C scenario. We call the result of this modeling "technology hybridized environmental-economic model with integrated scenarios" (THEMIS). As a case study, we apply THEMIS in an integrated environmental assessment of concentrating solar power. Life-cycle greenhouse gas emissions for this plant range from 33 to 95 g CO2 eq./kWh across different world regions in 2010, falling to 30-87 g CO2 eq./kWh in 2050. Using regional life cycle data yields insightful results. More generally, these results also highlight the need for systematic life cycle frameworks that capture the actual consequences and feedback effects of large-scale policies in the long term.

  14. Developing Students' Understanding of Industrially Relevant Economic and Life Cycle Assessments

    ERIC Educational Resources Information Center

    Bode, Claudia J.; Chapman, Clint; Pennybaker, Atherly; Subramaniam, Bala

    2017-01-01

    Training future leaders to understand life cycle assessment data is critical for effective research, business, and sociopolitical decision-making. However, the technical nature of these life cycle reports often makes them challenging for students and other nonexperts to comprehend. Therefore, we outline here the key takeaways from recent economic…

  15. Geothermal Water Use: Life Cycle Water Consumption, Water Resource Assessment, and Water Policy Framework

    DOE Data Explorer

    Schroeder, Jenna N.

    2014-06-10

    This report examines life cycle water consumption for various geothermal technologies to better understand factors that affect water consumption across the life cycle (e.g., power plant cooling, belowground fluid losses) and to assess the potential water challenges that future geothermal power generation projects may face. Previous reports in this series quantified the life cycle freshwater requirements of geothermal power-generating systems, explored operational and environmental concerns related to the geochemical composition of geothermal fluids, and assessed future water demand by geothermal power plants according to growth projections for the industry. This report seeks to extend those analyses by including EGS flash, both as part of the life cycle analysis and water resource assessment. A regional water resource assessment based upon the life cycle results is also presented. Finally, the legal framework of water with respect to geothermal resources in the states with active geothermal development is also analyzed.

  16. "ATLAS" Advanced Technology Life-cycle Analysis System

    NASA Technical Reports Server (NTRS)

    Lollar, Louis F.; Mankins, John C.; ONeil, Daniel A.

    2004-01-01

    Making good decisions concerning research and development portfolios-and concerning the best systems concepts to pursue - as early as possible in the life cycle of advanced technologies is a key goal of R&D management This goal depends upon the effective integration of information from a wide variety of sources as well as focused, high-level analyses intended to inform such decisions Life-cycle Analysis System (ATLAS) methodology and tool kit. ATLAS encompasses a wide range of methods and tools. A key foundation for ATLAS is the NASA-created Technology Readiness. The toolkit is largely spreadsheet based (as of August 2003). This product is being funded by the Human and Robotics The presentation provides a summary of the Advanced Technology Level (TRL) systems Technology Program Office, Office of Exploration Systems, NASA Headquarters, Washington D.C. and is being integrated by Dan O Neil of the Advanced Projects Office, NASA/MSFC, Huntsville, AL

  17. NASA Habitat Demonstration Unit (HDU) Deep Space Habitat Analog

    NASA Technical Reports Server (NTRS)

    Howe, A. Scott; Kennedy, Kriss J.; Gill, Tracy

    2013-01-01

    The NASA Habitat Demonstration Unit (HDU) vertical cylinder habitat was established as a exploration habitat testbed platform for integration and testing of a variety of technologies and subsystems that will be required in a human-occupied planetary surface outpost or Deep Space Habitat (DSH). The HDU functioned as a medium-fidelity habitat prototype from 2010-2012 and allowed teams from all over NASA to collaborate on field analog missions, mission operations tests, and system integration tests to help shake out equipment and provide feedback for technology development cycles and crew training. This paper documents the final 2012 configuration of the HDU, and discusses some of the testing that took place. Though much of the higher-fidelity functionality has 'graduated' into other NASA programs, as of this writing the HDU, renamed Human Exploration Research Analog (HERA), will continue to be available as a volumetric and operational mockup for NASA Human Research Program (HRP) research from 2013 onward.

  18. Endolithic microbial habitats as refuges for life in polyextreme environment of the Atacama Desert.

    PubMed

    Wierzchos, Jacek; Casero, M Cristina; Artieda, Octavio; Ascaso, Carmen

    2018-01-22

    The extremely harsh conditions of hyperarid deserts are a true challenge for microbial life. Microorganisms thriving in such polyextreme environments are fascinating as they can tell us more about life, its strategies and its boundaries than other groups of organisms. The Atacama Desert (North Chile) holds two world records of extreme environmental characteristics: the lowest rainfall and greatest surface ultraviolet radiation and total solar irradiance ever measured on Earth. Despite these limiting conditions for life, we recently identified several remarkable examples of endolithic habitats colonized by phototrophic and heterotrophic microorganisms in the hyperarid core of the Atacama Desert. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Taking Another Look at the Data Management Life Cycle: Deconstruction, Agile, and Community

    NASA Astrophysics Data System (ADS)

    Young, J. W.; Lenhardt, W. C.; Parsons, M. A.; Benedict, K. K.

    2014-12-01

    The data life cycle has figured prominently in describing the context of digital scientific data stewardship and cyberinfractructure in support of science. There are many different versions of the data life cycle, but they all follow a similar basic pattern: plan, collect, ingest, asses, preserve, discover, and reuse. The process is often interpreted in a fairly linear fashion despite it being a cycle conceptually. More recently at GeoData 2014 and elsewhere, questions have been raised about the utility of the data life cycle as it is currently represented. We are proposing to the community a re-examination of the data life cycle using an agile lens. Our goal is not to deploy agile methods, but to use agile principles as a heuristic to think about how to incorporate data stewardship across the scientific process from proposal stage to research and beyond. We will present alternative conceptualizations of the data life cycle with a goal to solicit feedback and to develop a new model for conceiving and describing the overall data stewardship process. We seek to re-examine past assumptions and shed new light on the challenges and necessity of data stewardship. The ultimate goal is to support new science through enhanced data interoperability, usability, and preservation.

  20. Life cycle approaches to sustainable consumption: a critical review.

    PubMed

    Hertwich, Edgar G

    2005-07-01

    The 2002 World Summit for Sustainable Development in Johannesburg called for a comprehensive set of programs focusing on sustainable consumption and production. According to world leaders, these programs should rely on life cycle assessment (LCA) to promote sustainable patterns of production and consumption. Cleaner production is a well-established activity, and it uses LCA. UNEP, the European Union, and a number of national organizations have now begun to work on sustainable consumption. In developing sustainable consumption policies and activities, the use of LCA presents interesting opportunities that are not yet well understood by policy makers. This paper reviews how life cycle approaches, primarily based on input-output analysis, have been used in the area of sustainable consumption: to inform policy making, select areas of action, identify which lifestyles are more sustainable, advise consumers, and evaluate the effectiveness of sustainable consumption measures. Information on consumption patterns usually comes from consumer expenditure surveys. Different study designs and a better integration with consumer research can provide further interesting insights. Life-cycle approaches still need to be developed and tested. Current research is mostly descriptive; policy makers, however, require more strategic analysis addressing their decision options, including scenario analysis and backcasting.

  1. Life cycle assessment-driven selection of industrial ecology strategies.

    PubMed

    Ardente, Fulvio; Cellura, Maurizio; Lo Brano, Valerio; Mistretta, Marina

    2010-01-01

    The paper presents an application of the Life-Cycle Assessment (LCA) to the planning and environmental management of an “eco-industrial cluster.” A feasibility study of industrial symbiosis in southern Italy is carried out, where interlinked companies share subproducts and scraps, services, structures, and plants to reduce the related environmental impact. In particular, the research focuses on new recycling solutions to create open recycling loops in which plastic subproducts and scraps are transferred to external production systems. The main environmental benefits are the reduction of resource depletion, air emissions, and landfilled wastes. The proposed strategies are also economically viable and they suggest cost abatement for the involved companies. This research shows the need for a multidisciplinary approach to data processing and to complexity managing of the investigated systems. In this context, life-cycle thinking is required to be promoted throughout the economy, as well to be as a part of all decisions on products and other criteria such as functionality, health, and safety. The Life-Cycle Assessment approach can be assumed as a methodology for influencing decision makers to make sustainable choices.

  2. Life Cycle Assessment of Metals: A Scientific Synthesis

    PubMed Central

    Nuss, Philip; Eckelman, Matthew J.

    2014-01-01

    We have assembled extensive information on the cradle-to-gate environmental burdens of 63 metals in their major use forms, and illustrated the interconnectedness of metal production systems. Related cumulative energy use, global warming potential, human health implications and ecosystem damage are estimated by metal life cycle stage (i.e., mining, purification, and refining). For some elements, these are the first life cycle estimates of environmental impacts reported in the literature. We show that, if compared on a per kilogram basis, the platinum group metals and gold display the highest environmental burdens, while many of the major industrial metals (e.g., iron, manganese, titanium) are found at the lower end of the environmental impacts scale. If compared on the basis of their global annual production in 2008, iron and aluminum display the largest impacts, and thallium and tellurium the lowest. With the exception of a few metals, environmental impacts of the majority of elements are dominated by the purification and refining stages in which metals are transformed from a concentrate into their metallic form. Out of the 63 metals investigated, 42 metals are obtained as co-products in multi output processes. We test the sensitivity of varying allocation rationales, in which the environmental burden are allocated to the various metal and mineral products, on the overall results. Monte-Carlo simulation is applied to further investigate the stability of our results. This analysis is the most comprehensive life cycle comparison of metals to date and allows for the first time a complete bottom-up estimate of life cycle impacts of the metals and mining sector globally. We estimate global direct and indirect greenhouse gas emissions in 2008 at 3.4 Gt CO2-eq per year and primary energy use at 49 EJ per year (9.5% of global use), and report the shares for all metals to both impact categories. PMID:24999810

  3. Life-cycle environmental inventory of passenger transportation modes in the United States

    NASA Astrophysics Data System (ADS)

    Chester, Mikhail Vin

    To appropriately mitigate environmental impacts from transportation, it is necessary for decision makers to consider the life-cycle energy consumption and emissions associated with each mode. A life-cycle energy, greenhouse gas, and criteria air pollutant emissions inventory is created for the passenger transportation modes of automobiles, urban buses, heavy rail transit, light rail transit, and aircraft in the U.S. Each mode's inventory includes an assessment of vehicles, infrastructure, and fuel components. For each component, analysis is performed for material extraction through use and maintenance in both direct and indirect (supply chain) processes. For each mode's life-cycle components, energy inputs and emission outputs are determined. Energy inputs include electricity and petroleum-based fuels. Emission outputs include greenhouse gases (CO2, CH4, and N2O) and criteria pollutants (CO, SO2, NOx , VOCs, and PM). The inputs and outputs are normalized by vehicle lifetime, vehicle mile traveled, and passenger mile traveled. A consistent system boundary is applied to all modal inventories which captures the entire life-cycle, except for end-of-life. For each modal life-cycle component, both direct and indirect processes are included if possible. A hybrid life-cycle assessment approach is used to estimate the components in the inventories. We find that life-cycle energy inputs and emission outputs increase significantly compared to the vehicle operational phase. Life-cycle energy consumption is 39-56% larger than vehicle operation for autos, 38% for buses, 93-160% for rail, and 19-24% for air systems per passenger mile traveled. Life-cycle greenhouse gas emissions are 47-65% larger than vehicle operation for autos, 43% for buses, 39-150% for rail, and 24-31% for air systems per passenger mile traveled. The energy and greenhouse gas increases are primarily due to vehicle manufacturing and maintenance, infrastructure construction, and fuel production. For criteria

  4. Application of Life Cycle Assessment (LCA) in Sugar Industries

    NASA Astrophysics Data System (ADS)

    Astuti, Arieyanti Dwi; Astuti, Rahayu Siwi Dwi; Hadiyanto, Hadiyanto

    2018-02-01

    Sugar is one of the main commodities that are needed for human life. The demand of sugar is very high with the trend increase from year to year. This condition makes the sugar industry become a leading industry that must be maintained sustainability. The sustainability of the sugar industry is influenced by the use of energy and natural resources and the resulting environmental impacts. Therefore, an effort is needed to analyze the environmental aspects and potential environmental impacts resulting from a product (sugar), by using Life Cycle Assessment (LCA). LCA is a very important tool for the analysis of a process/system from its cradle to grave. This technique is very useful in the estimation of energy usage and environmental load of a product/system. This paper aims to describe the main elements of sugar industries using Life Cycle Assessment.

  5. Externalities in a life cycle model with endogenous survival☆

    PubMed Central

    Kuhn, Michael; Wrzaczek, Stefan; Prskawetz, Alexia; Feichtinger, Gustav

    2011-01-01

    We study socially vs individually optimal life cycle allocations of consumption and health, when individual health care curbs own mortality but also has a spillover effect on other persons’ survival. Such spillovers arise, for instance, when health care activity at aggregate level triggers improvements in treatment through learning-by-doing (positive externality) or a deterioration in the quality of care through congestion (negative externality). We combine an age-structured optimal control model at population level with a conventional life cycle model to derive the social and private value of life. We then examine how individual incentives deviate from social incentives and how they can be aligned by way of a transfer scheme. The age-patterns of socially and individually optimal health expenditures and the transfer rate are derived. Numerical analysis illustrates the working of our model. PMID:28298810

  6. A Comparative Analysis of Life-Cycle Assessment Tools for End-of-Life Materials Management Systems

    EPA Science Inventory

    We identified and evaluated five life-cycle assessment tools that community decision makers can use to assess the environmental and economic impacts of end-of-life (EOL) materials management options. The tools evaluated in this report are waste reduction mode (WARM), municipal s...

  7. Emerald ash borer life cycle: a reassessment

    Treesearch

    David Cappaert; Deborah McCullough; Therese Poland

    2005-01-01

    To establish the life cycle of EAB was one of the first objectives of EAB research. Our expectation was that Agrilus planipennis phenology would coincide roughly with that of well-characterized Agrilus species such as A. anxius and A. bilineatus: 1) mid-summer adult flight and oviposition; 2)...

  8. Life cycle assessment of switchgrass- and corn stover-derived ethanol-fueled automobiles.

    PubMed

    Spatari, Sabrina; Zhang, Yimin; MacLean, Heather L

    2005-12-15

    Utilizing domestically produced cellulose-derived ethanol for the light-duty vehicle fleet can potentially improve the environmental performance and sustainability of the transport and energy sectors of the economy. A life cycle assessment model was developed to examine environmental implications of the production and use of ethanol in automobiles in Ontario, Canada. The results were compared to those of low-sulfur reformulated gasoline (RFG) in a functionally equivalent automobile. Two time frames were evaluated, one near-term (2010), which examines converting a dedicated energy crop (switchgrass) and an agricultural residue (corn stover) to ethanol; and one midterm (2020), which assumes technological improvements in the switchgrass-derived ethanol life cycle. Near-term results show that, compared to a RFG automobile, life cycle greenhouse gas (GHG) emissions are 57% lower for an E85-fueled automobile derived from switchgrass and 65% lower for ethanol from corn stover, on a grams of CO2 equivalent per kilometer basis. Corn stover ethanol exhibits slightly lower life cycle GHG emissions, primarily due to sharing emissions with grain production. Through projected improvements in crop and ethanol yields, results for the mid-term scenario show that GHG emissions could be 25-35% lower than those in 2010 and that, even with anticipated improvements in RFG automobiles, E85 automobiles could still achieve up to 70% lower GHG emissions across the life cycle.

  9. The Adaptability of Life on Earth and the Diversity of Planetary Habitats.

    PubMed

    Schulze-Makuch, Dirk; Airo, Alessandro; Schirmack, Janosch

    2017-01-01

    The evolutionary adaptability of life to extreme environments is astounding given that all life on Earth is based on the same fundamental biochemistry. The range of some physicochemical parameters on Earth exceeds the ability of life to adapt, but stays within the limits of life for other parameters. Certain environmental conditions such as low water availability in hyperarid deserts on Earth seem to be close to the limit of biological activity. A much wider range of environmental parameters is observed on planetary bodies within our Solar System such as Mars or Titan, and presumably even larger outside of our Solar System. Here we review the adaptability of life as we know it, especially regarding temperature, pressure, and water activity. We use then this knowledge to outline the range of possible habitable environments for alien planets and moons and distinguish between a variety of planetary environment types. Some of these types are present in our Solar System, others are hypothetical. Our schematic categorization of alien habitats is limited to life as we know it, particularly regarding to the use of solvent (water) and energy source (light and chemical compounds).

  10. The Adaptability of Life on Earth and the Diversity of Planetary Habitats

    PubMed Central

    Schulze-Makuch, Dirk; Airo, Alessandro; Schirmack, Janosch

    2017-01-01

    The evolutionary adaptability of life to extreme environments is astounding given that all life on Earth is based on the same fundamental biochemistry. The range of some physicochemical parameters on Earth exceeds the ability of life to adapt, but stays within the limits of life for other parameters. Certain environmental conditions such as low water availability in hyperarid deserts on Earth seem to be close to the limit of biological activity. A much wider range of environmental parameters is observed on planetary bodies within our Solar System such as Mars or Titan, and presumably even larger outside of our Solar System. Here we review the adaptability of life as we know it, especially regarding temperature, pressure, and water activity. We use then this knowledge to outline the range of possible habitable environments for alien planets and moons and distinguish between a variety of planetary environment types. Some of these types are present in our Solar System, others are hypothetical. Our schematic categorization of alien habitats is limited to life as we know it, particularly regarding to the use of solvent (water) and energy source (light and chemical compounds). PMID:29085352

  11. Optimal seasonal schedules and the relative dominance of heteromorphic and isomorphic life cycles in macroalgae.

    PubMed

    Bessho, Kazuhiro; Iwasa, Yoh

    2010-11-21

    Marine macroalgae (seaweed) show diverse life cycles. Species with a heteromorphic life cycle have a large multicellular algal body in one generation but have a very small body in the second generation of the same year. In contrast, the diploid and haploid life forms of isomorphic species have similar morphology, and these species often have more than two generations in a year. Here, we first study the optimal life cycle schedule of marine macroalgae when daily mortality changes seasonally, and then we discuss the conditions for coexistence and relative dominance of different life cycles. According to the optimal life cycle schedule, heteromorphic species tend to have a generation with a large algal body when mortality is low, and a microscopic-sized generation when mortality is high. In contrast, isomorphic species tend to mature when body size reaches a threshold value that is the same for different generations. We then examine the coexistence of the two life cycles when growth rate decreases with biomass. The model predicts that (1) at high latitudes (i.e., in strongly seasonal environments), heteromorphic species are likely to dominate over isomorphic species, and (2) species with a heteromorphic life cycle should dominate in the supratidal and upper intertidal zones where macroalgae tend to suffer high mortality, and also in the subtidal zone, where mortality is low, whereas isomorphic species are likely to be more successful when mortality is intermediate. These predictions are consistent with the observed distribution patterns of the two life cycles in macroalgae. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. The life cycle of pear thrips, Taeniothrips inconsequens (Uzel) in Vermont

    Treesearch

    Margaret Skinner; Bruce L. Parker; Sandra H. Wilmot

    1991-01-01

    Life history information has been collected for pear thrips in orchard habitats in California and British Columbia (Cameron & Treherne 1918, Bailey 1944). However such information is not available for this insect in a northern hardwood forest ecosystem in the eastern United States. Research is currently underway at the University of Vermont to determine the pear...

  13. Extensive epigenetic reprogramming during the life cycle of Marchantia polymorpha.

    PubMed

    Schmid, Marc W; Giraldo-Fonseca, Alejandro; Rövekamp, Moritz; Smetanin, Dmitry; Bowman, John L; Grossniklaus, Ueli

    2018-01-25

    In plants, the existence and possible role of epigenetic reprogramming has been questioned because of the occurrence of stably inherited epialleles. Evidence suggests that epigenetic reprogramming does occur during land plant reproduction, but there is little consensus on the generality and extent of epigenetic reprogramming in plants. We studied DNA methylation dynamics during the life cycle of the liverwort Marchantia polymorpha. We isolated thalli and meristems from male and female gametophytes, archegonia, antherozoids, as well as sporophytes at early and late developmental stages, and compared their DNA methylation profiles. Of all cytosines tested for differential DNA methylation, 42% vary significantly in their methylation pattern throughout the life cycle. However, the differences are limited to few comparisons between specific stages of the life cycle and suggest four major epigenetic states specific to sporophytes, vegetative gametophytes, antherozoids, and archegonia. Further analyses indicated clear differences in the mechanisms underlying reprogramming in the gametophytic and sporophytic generations, which are paralleled by differences in the expression of genes involved in DNA methylation. Differentially methylated cytosines with a gain in methylation in antherozoids and archegonia are enriched in the CG and CHG contexts, as well as in gene bodies and gene flanking regions. In contrast, gain of DNA methylation during sporophyte development is mostly limited to the CHH context, LTR retrotransposons, DNA transposons, and repeats. We conclude that epigenetic reprogramming occurs at least twice during the life cycle of M. polymorpha and that the underlying mechanisms are likely different between the two events.

  14. Invaded invaders: Infection of invasive Brown Treesnakes on Guam by an exotic larval cestode with a life cycle comprised of non-native hosts

    USGS Publications Warehouse

    Holldorf, Elden T; Siers, Shane R.; Richmond, Jonathan Q.; Klug, Page E.; Reed, Robert

    2015-01-01

    We discovered that B. irregularis inhabiting a small area of forested habitat in a freshwater watershed on Guam are often infected by a novel parasite of Asian origin. While further work is needed, this species of Spirometra, itself a non-native species, likely depends on a suite of recently introduced hosts from different parts of the world to complete the life cycle. This baseline study provides little evidence of any effects on host fitness, but additional data are needed to more thoroughly explore the consequences of infection in this invasive snake population.

  15. Fatigue life estimation on coke drum due to cycle optimization

    NASA Astrophysics Data System (ADS)

    Siahaan, Andrey Stephan; Ambarita, Himsar; Kawai, Hideki; Daimaruya, Masashi

    2018-04-01

    In the last decade, due to the increasing demand of petroleum product, the necessity for converting the heavy oil are increasing. Thus, demand for installing coke drum in whole world will be increase. The coke drum undergoes the cyclic high temperature and suddenly cooling but in fact is not designed to withstand that kind of cycle, thus the operational life of coke drum is much shorter in comparison to other equipment in oil refinery. Various factors determine in order to improve reliability and minimize the down time, and it is found that the cycle optimization due to cycle, temperature, and pressure have an important role. From this research it is found that the fatigue life of the short cycle is decrease by a half compare to the normal cycle. It also found that in the preheating stage, the stress peak is far exceed the yield strength of coke drum material and fall into plastic deformation. This is happened because of the temperature leap in the preheating stage that cause thermal shock in the upper part of the skirt of the coke drum.

  16. Evolution of dispersal in spatially and temporally variable environments: The importance of life cycles.

    PubMed

    Massol, François; Débarre, Florence

    2015-07-01

    Spatiotemporal variability of the environment is bound to affect the evolution of dispersal, and yet model predictions strongly differ on this particular effect. Recent studies on the evolution of local adaptation have shown that the life cycle chosen to model the selective effects of spatiotemporal variability of the environment is a critical factor determining evolutionary outcomes. Here, we investigate the effect of the order of events in the life cycle on the evolution of unconditional dispersal in a spatially heterogeneous, temporally varying landscape. Our results show that the occurrence of intermediate singular strategies and disruptive selection are conditioned by the temporal autocorrelation of the environment and by the life cycle. Life cycles with dispersal of adults versus dispersal of juveniles, local versus global density regulation, give radically different evolutionary outcomes that include selection for total philopatry, evolutionary bistability, selection for intermediate stable states, and evolutionary branching points. Our results highlight the importance of accounting for life-cycle specifics when predicting the effects of the environment on evolutionarily selected trait values, such as dispersal, as well as the need to check the robustness of model conclusions against modifications of the life cycle. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  17. Gate-to-gate Life-Cycle Inventory of Hardboard Production in North America

    Treesearch

    Richard Bergman

    2014-01-01

    Whole-building life-cycle assessments (LCAs) populated by life-cycle inventory (LCI) data are incorporated into environmental footprint software tools for establishing green building certification by building professionals and code. However, LCI data on some wood building products are still needed to help fill gaps in the data and thus provide a more complete picture...

  18. Growing up in the Ocean: Complex Life Cycles of Common Marine Invertebrates

    ERIC Educational Resources Information Center

    Bennett, Katie; Hiebert, Laurel

    2010-01-01

    Most people are familiar with the concept that animals come in all shapes and sizes and that the body plan of some animals can completely transform during their lifetime. Well-known examples of such complex life cycles of terrestrial animals include butterflies and frogs. Many people are unaware, however, that complex life cycles are exceedingly…

  19. Integrated Metrics for Improving the Life Cycle Approach to Assessing Product System Sustainability

    EPA Science Inventory

    Life cycle approaches are critical for identifying and managing to reduce burdens in the sustainability of product systems. While these methods can indicate potential environmental impacts of a product, current Life Cycle Assessment (LCA) methods fail to integrate the multiple im...

  20. The cycle life chemistry of ambient-temperature secondary lithium cells

    NASA Technical Reports Server (NTRS)

    Somoano, R.; Carter, B. J.; Subba Rao, S.; Shen, D.; Yen, S. P. S.

    1985-01-01

    The Jet Propulsion Laboratory is involved in a NASA-sponsored research program to demonstrate the feasibility of ambient-temperature secondary lithium batteries for geosynchronous space applications. Encouraging cycle life has been demonstrated in sealed, cathode-limited laboratory cells. However, the cell capacity declines with cycle life. The results of recent studies of the lithium electrode passivation chemistry, and of conductive diluents for TiS2 cathodes and their possible contribution to capacity decline, are here presented. Technical issues associated with the unique operational requirements of a geosynchronous mission are also described.

  1. [Specific manifestations of polyvariant life cycles in ground beetles (Coleoptera, Carabidae) along latitudinal gradient].

    PubMed

    Matalin, A V

    2014-01-01

    The life cycles of Carabidae are highly diverse, and 25 variants of these cycles are realized In the European part of Russia, from semideserts to continental tundras. The diversity of the life cycle spectrum sharply decreases (by more than half) upon transition from nemoral to boreal forest communities, and its phenological unification takes place at high latitudes. The greatest proportion of species with polyvariant development (25%) is characteristic of temporal latitudes, which may be explained by relatively long growing season and considerable cenotic diversity. In both southern (semidesert and steppe) and northern regions (middle and northern boreal forests), this proportion does not exceed 5%. At low latitudes, the polyvariant pattern of development is often manifested in the form of facultative bivoltine life cycles or as facultative biennial life cycles in species with the initial "spring" breeding type.

  2. Long-term shifts in life-cycle energy efficiency and carbon intensity.

    PubMed

    Yeh, Sonia; Mishra, Gouri Shankar; Morrison, Geoff; Teter, Jacob; Quiceno, Raul; Gillingham, Kenneth; Riera-Palou, Xavier

    2013-03-19

    The quantity of primary energy needed to support global human activity is in large part determined by how efficiently that energy is converted to a useful form. We estimate the system-level life-cycle energy efficiency (EF) and carbon intensity (CI) across primary resources for 2005-2100. Our results underscore that although technological improvements at each energy conversion process will improve technology efficiency and lead to important reductions in primary energy use, market mediated effects and structural shifts toward less efficient pathways and pathways with multiple stages of conversion will dampen these efficiency gains. System-level life-cycle efficiency may decrease as mitigation efforts intensify, since low-efficiency renewable systems with high output have much lower GHG emissions than some high-efficiency fossil fuel systems. Climate policies accelerate both improvements in EF and the adoption of renewable technologies, resulting in considerably lower primary energy demand and GHG emissions. Life-cycle EF and CI of useful energy provide a useful metric for understanding dynamics of implementing climate policies. The approaches developed here reiterate the necessity of a combination of policies that target efficiency and decarbonized energy technologies. We also examine life-cycle exergy efficiency (ExF) and find that nearly all of the qualitative results hold regardless of whether we use ExF or EF.

  3. Effect of KOH concentration on LEO cycle life of IPV nickel-hydrogen flight cells. An update

    NASA Technical Reports Server (NTRS)

    Smithrick, John J.; Hall, Stephen W.

    1991-01-01

    An update of validation test results confirming the breakthrough in LEO cycle life of nickel-hydrogen cells containing 26 percent potassium hydroxide (KOH) electrolyte is presented. A breakthrough in the LEO cycle life of individual pressure vessel nickel-hydrogen cells is reported. The cycle life of boiler plate cells containing 26 percent KOH electrolyte was about 40,000 LEO cycles compared to 3500 cycles for cells containing 31 percent KOH.

  4. Effect of KOH concentration on LEO cycle life of IPV nickel-hydrogen flight cells - An update

    NASA Technical Reports Server (NTRS)

    Smithrick, John J.; Hall, Stephen W.

    1991-01-01

    An update of validation test results confirming the breakthrough in LEO cycle life of nickel-hydrogen cells containing 26 percent potassium hydroxide (KOH) electrolyte is presented. A breakthrough in the LEO cycle life of individual pressure vessel nickel-hydrogen cells is reported. The cycle life of boiler plate cells containing 26 percent KOH electrolyte was about 40,000 LEO cycles compared to 3500 cycles for cells containing 31 percent KOH.

  5. 76 FR 41525 - Hewlett Packard Global Parts Supply Chain, Global Product Life Cycles Management Unit Including...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-14

    ... Parts Supply Chain, Global Product Life Cycles Management Unit Including Teleworkers Reporting to... workers of Hewlett Packard, Global Parts Supply Chain, Global Product Life Cycles Management Unit...). Since eligible workers of Hewlett Packard, Global Parts Supply Chain, Global Product Life Cycles...

  6. The Cosmic Habitat for Earth-Life and the Issue of Sustainable Development

    NASA Astrophysics Data System (ADS)

    Piątek, Zdzisława

    2017-12-01

    The subjects under consideration here are the philosophical consequences arising as the cosmic dimension to ecology is taken into account. If the habitat for Earthlife is a part of the cosmic environment, then cosmology and astrophysics become a part of ecology. The human species is furthermore a participant in a vast process of cosmic evolution, with sustainable-development strategy thus defi ning the conditions for - and time needed to achieve - a technological civilisation allowing Earth-life to be evacuated to another part of the galaxy as and when the further existence of life on this planet becomes (or threatens to become) an impossibility. In the context of such a cosmic perspective, the value ascribable to our scientifi c and technological civilisation (and future versions thereof) changes, given that only this kind of civilisation offers a chance for Earth-life to persist in an extra-terrestrial environment.

  7. Linking movement and reproductive history of brook trout to assess habitat connectivity in a heterogeneous stream network

    Treesearch

    Yoichiro Kanno; Benjamin H. Letcher; Jason A. Coombs; Keith H. Nislow; Andrew R. Whiteley

    2014-01-01

    Defining functional connectivity between habitats in spatially heterogeneous landscapes is a particular challenge for small-bodied aquatic species. Traditional approaches (e.g. mark-recapture studies) preclude an assessment of animal movement over the life cycle (birth to reproduction), and movement of individuals may not represent the degree of gene movement for...

  8. Planning Evaluation through the Program Life Cycle

    ERIC Educational Resources Information Center

    Scheirer, Mary Ann; Mark, Melvin M.; Brooks, Ariana; Grob, George F.; Chapel, Thomas J.; Geisz, Mary; McKaughan, Molly; Leviton, Laura

    2012-01-01

    Linking evaluation methods to the several phases of a program's life cycle can provide evaluation planners and funders with guidance about what types of evaluation are most appropriate over the trajectory of social and educational programs and other interventions. If methods are matched to the needs of program phases, evaluation can and should…

  9. Transpiration during life cycle in controlled wheat growth

    NASA Technical Reports Server (NTRS)

    Volk, Tyler; Rummel, John D.

    1990-01-01

    A previously developed model of wheat growth, designed for convenient incorporation into system level models of advanced space life support systems is described. The model is applied to data from an experiment that grew wheat under controlled conditions and measured fresh biomass and cumulated transpiration as a function of time. The adequacy of modeling the transpiration as proportional to the inedible biomass and an age factor that varies during the life cycle are discussed.

  10. The universe: a cryogenic habitat for microbial life.

    PubMed

    Wickramasinghe, Chandra

    2004-04-01

    Panspermia, an ancient idea, posits that microbial life is ubiquitous in the Universe. After several decades of almost irrational rejection, panspermia is at last coming to be regarded as a serious contender for the beginnings of life on our planet. Astronomical data is shown to be consistent with the widespread distribution of complex organic molecules and dust particles that may have a biological provenance. A minuscule (10(-21)) survival rate of freeze-dried bacteria in space is all that is needed to ensure the continual re-cycling of cosmic microbial life in the galaxy. Evidence that terrestrial life may have come from elsewhere in the solar system has accumulated over the past decade. Mars is seen by some as a possible source of terrestrial life, but some hundreds of billions of comets that enveloped the entire solar system, are a far more likely primordial reservoir of life. Comets would then have seeded Earth, Mars, and indeed all other habitable planetary bodies in the inner regions of the solar system. The implications of this point of view, which was developed in conjunction with the late Sir Fred Hoyle since the 1970s, are now becoming amenable to direct empirical test by studies of pristine organic material in the stratosphere. The ancient theory of panspermia may be on the verge of vindication, in which case the entire universe would be a grand crucible of cryomicrobiology.

  11. Loss and modification of habitat: Chapter 1

    USGS Publications Warehouse

    Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.

    2012-01-01

    water balance (Thorson and Svihla 1943; Brattstrom 1963; Tracy 1976). Hence, individuals require and seek specific microhabitats that maintain their preferred body temperature while at the same time reducing water loss or allowing individuals to re-hydrate. Amphibians also possess relatively few physical attributes that protect them from predators. Although they may avoid predators behaviourally or deter them by skin toxins, amphibians lack defensive shells or hardened cuticles, do not have protective teeth or claws, and most are insufficiently fast to escape predators. Hence, they are relatively dependent on sites that conceal or protect them from predation. Most amphibians also differ significantly from other vertebrates in possessing a complex two-phase life cycle: the pre-metamorphic larval (tadpole) stage and the post-metamorphic juvenile and adult stage (Wilbur 1980, 1984). Most amphibian species have two distinct econes (Heatwole 1989), each with different habitat requirements, the larvae being aquatic and the post-metamorphic animals more terrestrial. The habitats required by the two phases can differ greatly, but both are essential to the survival of a species. However, amphibian diversity is great and exceptions to this general pattern exist. For example, some species have direct development without going through a larval stage and are fully terrestrial, whereas the larvae of other species can reach sexual maturity without going through metamorphosis (i.e., neoteny) and are fully aquatic.

  12. Indicators: Physical Habitat Complexity

    EPA Pesticide Factsheets

    Physical habitat complexity measures the amount and variety of all types of cove at the water’s edge in lakes. In general, dense and varied shoreline habitat is able to support more diverse communities of aquatic life.

  13. Comparison of energy-based indicators used in life cycle assessment tools for buildings

    EPA Science Inventory

    Traditionally, building rating systems focused on, among others, energy used during operational stage. Recently, there is a strong push by these rating systems to include the life cycle energy use of buildings, particularly using Life Cycle Assessment (LCA), by offering credits t...

  14. The Process of Life Cycle Cost Analysis: Projecting Economic Consequences of Design Decisions

    ERIC Educational Resources Information Center

    AIA Journal, 1976

    1976-01-01

    Life-cycle cost analysis deals with both present and future costs and attempts to relate the two as a basis for making decisions. This article lays the groundwork for a better understanding of the techniques of life-cycle cost analysis. (Author/MLF)

  15. Habitat Suitability Index Models: Pronghorn

    USGS Publications Warehouse

    Allen, Arthur W.; Cook, John G.; Armbruster, Michael J.

    1984-01-01

    This is one of a series of publications that provide information on the habitat requirements of selected fish and wildlife species. Literature describing the relationship between habitat variables related to life requisites and habitat suitability for the pronghorn (Antilocapra americana) are synthesized. These data are subsequently used to develop Habitat Suitability Index (HSI) models. The HSI models are designed to provide information that can be used in impact assessment and habitat management.

  16. Geographic variation and evolution in the life cycle of the witch-hazel leaf gall aphid, Hormaphis hamamelidis.

    PubMed

    von Dohlen, C D; Gill, D E

    1989-02-01

    Two divergent life cycles associated with different elevations and latitudes have been documented for the witch-hazel leaf gall aphid, Hormaphis hamamelidis. At low elevation in northern Virginia, the aphid had seven distinct generations alternating between the primary host, witchhazel (Hamamelis virginiana), and a secondary host, river birch (Betula nigra). These findings confirm the original published life cycle description for the same locality. A second, abbreviated life cycle consisting of only three generations restricted to witch-hazel was discovered at high elevation (1000 m) in north central and northwestern Virginia. Aphids of both life cycles were sympatric at a middle elevation site. The life cycles and morphology suggest that the two forms are separate species. Although monoecious life cycles on primary hosts in aphids generally are thought to be ancestral to complex host-alternating ones, it is certainly possible that monoecious cycles are sometimes secondarily derived from complex cycles. By constructing a preliminary phylogeny of the described species in the tribe Hormaphidini, we propose that the abbreviated life cycle is derived from the complex one in the case of these witchhazel gall aphids. Our findings are discussed in the context of current theory regarding the evolutionary stability of complex life cycles.

  17. Evaluation program for secondary spacecraft cells: Cycle life test

    NASA Technical Reports Server (NTRS)

    Harkness, J. D.

    1979-01-01

    The service life and storage stability for several storage batteries were determined. The batteries included silver-zinc batteries, nickel-cadmium batteries, and silver-cadmium batteries. The cell performance characteristics and limitations are to be used by spacecraft power systems planners and designers. A statistical analysis of the life cycle prediction and cause of failure versus test conditions is presented.

  18. LIFE CYCLE DESIGN OF MILK AND JUICE PACKAGING

    EPA Science Inventory

    A life cycle design demonstration project was initiated between the U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Dow Chemical Company, and the University of Michigan to investigate milk and juice packagie design. The primary objective of ...

  19. A Growth Model for Academic Program Life Cycle (APLC): A Theoretical and Empirical Analysis

    ERIC Educational Resources Information Center

    Acquah, Edward H. K.

    2010-01-01

    Academic program life cycle concept states each program's life flows through several stages: introduction, growth, maturity, and decline. A mixed-influence diffusion growth model is fitted to enrolment data on academic programs to analyze the factors determining progress of academic programs through their life cycles. The regression analysis yield…

  20. Research planning criteria for regenerative life-support systems applicable to space habitats

    NASA Technical Reports Server (NTRS)

    Spurlock, J.; Cooper, W.; Deal, P.; Harlan, A.; Karel, M.; Modell, M.; Moe, P.; Phillips, J.; Putnam, D.; Quattrone, P.

    1979-01-01

    The second phase of analyses that were conducted by the Life Support Systems Group of the 1977 NASA Ames Summer Study is described. This phase of analyses included a preliminary review of relevant areas of technology that can contribute to the development of closed life-support systems for space habitats, the identification of research options in these areas of technology, and the development of guidelines for an effective research program. The areas of technology that were studied included: (1) nutrition, diet, and food processing; (2) higher plant agriculture; (3) animal agriculture; (4) waste conversion and resource recovery; and (5) system stability and safety. Results of these analyses, including recommended research options and criteria for establishing research priorities among these many options, are discussed.

  1. Life-Cycle Assessment of Cookstove Fuels in India and China ...

    EPA Pesticide Factsheets

    A life cycle assessment (LCA) was conducted to compare the environmental footprint of current and possible fuels used for cooking within China and India. Current fuel mix profiles are compared to scenarios of projected differences in and/or cleaner cooking fuels. Results are reported for a suite of relevant life cycle impact assessment indicators: global climate change, energy demand, fossil depletion, water consumption, particulate matter formation, acidification, eutrophication and photochemical smog formation. Traditional fuels demonstrate notably poor relative performance in particulate matter formation, photochemical oxidant formation, freshwater eutrophication, and black carbon emissions. Most fuels demonstrate trade-offs between impact categories. Stove efficiency is found to be a crucial variable determining environmental performance across all impact categories. The study shows that electricity and many of the processed fuels, while yielding emission reductions in homes at the point of use, transfer many of those emissions upstream into the processing and distribution life cycle stage. To conduct LCA study of the cookstove fuels being used in India and China to determine how fuels and stoves compare based on a holistic assessment considering the LCA environmental tradeoffs

  2. Environmental impacts of lighting technologies - Life cycle assessment and sensitivity analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Welz, Tobias; Hischier, Roland, E-mail: Roland.Hischier@empa.ch; Hilty, Lorenz M.

    2011-04-15

    With two regulations, 244/2009 and 245/2009, the European Commission recently put into practice the EuP Directive in the area of lighting devices, aiming to improve energy efficiency in the domestic lighting sector. This article presents a comprehensive life cycle assessment comparison of four different lighting technologies: the tungsten lamp, the halogen lamp, the conventional fluorescent lamp and the compact fluorescent lamp. Taking advantage of the most up-to-date life cycle inventory database available (ecoinvent data version 2.01), all life cycle phases were assessed and the sensitivity of the results for varying assumptions analysed: different qualities of compact fluorescent lamps (production phase),more » different electricity mixes (use phase), and end-of-life scenarios for WEEE recycling versus municipal solid waste incineration (disposal phase). A functional unit of 'one hour of lighting' was defined and the environmental burdens for the whole life cycle for all four lamp types were calculated, showing a clearly lower impact for the two gas-discharge lamps, i.e. the fluorescent and the compact fluorescent lamp. Differences in the product quality of the compact fluorescent lamps reveal to have only a very small effect on the overall environmental performance of this lamp type; a decline of the actual life time of this lamp type doesn't result in a change of the rank order of the results of the here examined four lamp types. It was also shown that the environmental break-even point of the gas-discharge lamps is reached long before the end of their expected life-span. All in all, it can be concluded that a change from today's tungsten lamp technology to a low-energy-consuming technology such as the compact fluorescent lamp results in a substantial environmental benefit.« less

  3. The Tropopause Inversion Layer in Baroclinic Life Cycle Experiments

    NASA Astrophysics Data System (ADS)

    Wirth, Volkmar; Erler, Andre

    2010-05-01

    The Tropopause Inversion Layer (TIL) is a region of enhanced static stability just above the thermal tropopause. It is a ubiquitous feature in midlatitudes and is well characterized by observations; however, it still lacks a full theoretical explanation. The current study uses adiabatic baroclinic life-cycle experiments in order to investigate dynamical mechanisms that lead to the formation of a TIL. Consistent with earlier results, no TIL is found above cyclonic anomalies, while a pronounced TIL is found above anticyclonic anomalies early during the life cycle. Interestingly, regarding tropopause based global mean profiles, a TIL can be seen only much later during the life cycle, at a time when wave breaking starts to occur. There is a significant rise of the thermal tropopause, which is spatially and temporally correlated with TIL formation. In contrast, the dynamical tropopause does not rise significantly and does not exhibit a TIL in the global mean. The results of these experiments are interpreted using earlier results about the nonlinear dependence of the TIL amplitude on the scale of the tropopause anomaly. The analysis suggests that the TIL (as a global mean feature) is linked to a strongly asymmetric distribution of cyclonic and anticyclonic anomalies, which occurs after the wave breaking event.

  4. Modeling the influence of genetic and environmental variation on the expression of plant life cycles across landscapes.

    PubMed

    Burghardt, Liana T; Metcalf, C Jessica E; Wilczek, Amity M; Schmitt, Johanna; Donohue, Kathleen

    2015-02-01

    Organisms develop through multiple life stages that differ in environmental tolerances. The seasonal timing, or phenology, of life-stage transitions determines the environmental conditions to which each life stage is exposed and the length of time required to complete a generation. Both environmental and genetic factors contribute to phenological variation, yet predicting their combined effect on life cycles across a geographic range remains a challenge. We linked submodels of the plasticity of individual life stages to create an integrated model that predicts life-cycle phenology in complex environments. We parameterized the model for Arabidopsis thaliana and simulated life cycles in four locations. We compared multiple "genotypes" by varying two parameters associated with natural genetic variation in phenology: seed dormancy and floral repression. The model predicted variation in life cycles across locations that qualitatively matches observed natural phenology. Seed dormancy had larger effects on life-cycle length than floral repression, and results suggest that a genetic cline in dormancy maintains a life-cycle length of 1 year across the geographic range of this species. By integrating across life stages, this approach demonstrates how genetic variation in one transition can influence subsequent transitions and the geographic distribution of life cycles more generally.

  5. LIFE CYCLE BASED STUDIES ON BIOETHANOL FUEL FOR SUSTAINABLE TRANSPORTATION: A LITERATURE REVIEW

    EPA Science Inventory

    A literature search was conducted and revealed 45 publications (1996-2005) that compare bio-ethanol systems to conventional fuel on a life-cycle basis, or using life cycle assessment. Feedstocks, such as sugar beets, wheat, potato, sugar cane, and corn, have been investigated in...

  6. Gimme shelter--the relative sensitivity of parasitic nematodes with direct and indirect life cycles to climate change.

    PubMed

    Molnár, Péter K; Dobson, Andrew P; Kutz, Susan J

    2013-11-01

    Climate change is expected to alter the dynamics of host-parasite systems globally. One key element in developing predictive models for these impacts is the life cycle of the parasite. It is, for example, commonly assumed that parasites with an indirect life cycle would be more sensitive to changing environmental conditions than parasites with a direct life cycle due to the greater chance that at least one of their obligate host species will go extinct. Here, we challenge this notion by contrasting parasitic nematodes with a direct life cycle against those with an indirect life cycle. Specifically, we suggest that behavioral thermoregulation by the intermediate host may buffer the larvae of indirectly transmitted parasites against temperature extremes, and hence climate warming. We term this the 'shelter effect'. Formalizing each life cycle in a comprehensive model reveals a fitness advantage for the direct life cycle over the indirect life cycle at low temperatures, but the shelter effect reverses this advantage at high temperatures. When examined for seasonal environments, the models suggest that climate warming may in some regions create a temporal niche in mid-summer that excludes parasites with a direct life cycle, but allows parasites with an indirect life cycle to persist. These patterns are amplified if parasite larvae are able to manipulate their intermediate host to increase ingestion probability by definite hosts. Furthermore, our results suggest that exploiting the benefits of host sheltering may have aided the evolution of indirect life cycles. Our modeling framework utilizes the Metabolic Theory of Ecology to synthesize the complexities of host behavioral thermoregulation and its impacts on various temperature-dependent parasite life history components in a single measure of fitness, R0 . It allows quantitative predictions of climate change impacts, and is easily generalized to many host-parasite systems. © 2013 John Wiley & Sons Ltd.

  7. 78 FR 47012 - Developing Software Life Cycle Processes Used in Safety Systems of Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-02

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Developing Software Life Cycle Processes Used in... revised regulatory guide (RG), revision 1 of RG 1.173, ``Developing Software Life Cycle Processes for... Developing a Software Project Life Cycle Process,'' issued 2006, with the clarifications and exceptions as...

  8. Policy implications of uncertainty in modeled life-cycle greenhouse gas emissions of biofuels.

    PubMed

    Mullins, Kimberley A; Griffin, W Michael; Matthews, H Scott

    2011-01-01

    Biofuels have received legislative support recently in California's Low-Carbon Fuel Standard and the Federal Energy Independence and Security Act. Both present new fuel types, but neither provides methodological guidelines for dealing with the inherent uncertainty in evaluating their potential life-cycle greenhouse gas emissions. Emissions reductions are based on point estimates only. This work demonstrates the use of Monte Carlo simulation to estimate life-cycle emissions distributions from ethanol and butanol from corn or switchgrass. Life-cycle emissions distributions for each feedstock and fuel pairing modeled span an order of magnitude or more. Using a streamlined life-cycle assessment, corn ethanol emissions range from 50 to 250 g CO(2)e/MJ, for example, and each feedstock-fuel pathway studied shows some probability of greater emissions than a distribution for gasoline. Potential GHG emissions reductions from displacing fossil fuels with biofuels are difficult to forecast given this high degree of uncertainty in life-cycle emissions. This uncertainty is driven by the importance and uncertainty of indirect land use change emissions. Incorporating uncertainty in the decision making process can illuminate the risks of policy failure (e.g., increased emissions), and a calculated risk of failure due to uncertainty can be used to inform more appropriate reduction targets in future biofuel policies.

  9. Life-cycle energy impacts for adapting an urban water supply system to droughts.

    PubMed

    Lam, Ka Leung; Stokes-Draut, Jennifer R; Horvath, Arpad; Lane, Joe L; Kenway, Steven J; Lant, Paul A

    2017-12-15

    In recent years, cities in some water stressed regions have explored alternative water sources such as seawater desalination and potable water recycling in spite of concerns over increasing energy consumption. In this study, we evaluate the current and future life-cycle energy impacts of four alternative water supply strategies introduced during a decade-long drought in South East Queensland (SEQ), Australia. These strategies were: seawater desalination, indirect potable water recycling, network integration, and rainwater tanks. Our work highlights the energy burden of alternative water supply strategies which added approximately 24% life-cycle energy use to the existing supply system (with surface water sources) in SEQ even for a current post-drought low utilisation status. Over half of this additional life-cycle energy use was from the centralised alternative supply strategies. Rainwater tanks contributed an estimated 3% to regional water supply, but added over 10% life-cycle energy use to the existing system. In the future scenario analysis, we compare the life-cycle energy use between "Normal", "Dry", "High water demand" and "Design capacity" scenarios. In the "Normal" scenario, a long-term low utilisation of the desalination system and the water recycling system has greatly reduced the energy burden of these centralised strategies to only 13%. In contrast, higher utilisation in the unlikely "Dry" and "Design capacity" scenarios add 86% and 140% to life-cycle energy use of the existing system respectively. In the "High water demand" scenario, a 20% increase in per capita water use over 20 years "consumes" more energy than is used by the four alternative strategies in the "Normal" scenario. This research provides insight for developing more realistic long-term scenarios to evaluate and compare life-cycle energy impacts of drought-adaptation infrastructure and regional decentralised water sources. Scenario building for life-cycle assessments of water supply

  10. Life cycle evolution: was the eumetazoan ancestor a holopelagic, planktotrophic gastraea?

    PubMed

    Nielsen, Claus

    2013-08-16

    Two theories for the origin of animal life cycles with planktotrophic larvae are now discussed seriously: The terminal addition theory proposes a holopelagic, planktotrophic gastraea as the ancestor of the eumetazoans with addition of benthic adult stages and retention of the planktotrophic stages as larvae, i.e. the ancestral life cycles were indirect. The intercalation theory now proposes a benthic, deposit-feeding gastraea as the bilaterian ancestor with a direct development, and with planktotrophic larvae evolving independently in numerous lineages through specializations of juveniles. Information from the fossil record, from mapping of developmental types onto known phylogenies, from occurrence of apical organs, and from genetics gives no direct information about the ancestral eumetazoan life cycle; however, there are plenty of examples of evolution from an indirect development to direct development, and no unequivocal example of evolution in the opposite direction. Analyses of scenarios for the two types of evolution are highly informative. The evolution of the indirect spiralian life cycle with a trochophora larva from a planktotrophic gastraea is explained by the trochophora theory as a continuous series of ancestors, where each evolutionary step had an adaptational advantage. The loss of ciliated larvae in the ecdysozoans is associated with the loss of outer ciliated epithelia. A scenario for the intercalation theory shows the origin of the planktotrophic larvae of the spiralians through a series of specializations of the general ciliation of the juvenile. The early steps associated with the enhancement of swimming seem probable, but the following steps which should lead to the complicated downstream-collecting ciliary system are without any advantage, or even seem disadvantageous, until the whole structure is functional. None of the theories account for the origin of the ancestral deuterostome (ambulacrarian) life cycle. All the available information is

  11. Low Life Cycle Cost Paratransit Vehicle Design Study

    DOT National Transportation Integrated Search

    1978-08-01

    A preliminary design and cost study was performed for a low life cycle cost paratransit vehicle. The manufacturing technique and cost analysis were based on limited production of 5000 units per year for a ten year period. The vehicle configuration re...

  12. Transportation Life Cycle Assessment (LCA) Synthesis, Phase II

    DOT National Transportation Integrated Search

    2018-04-24

    The Transportation Life Cycle Assessment (LCA) Synthesis includes an LCA Learning Module Series, case studies, and analytics on the use of the modules. The module series is a set of narrated slideshows on topics related to environmental LCA. Phase I ...

  13. LIFE CYCLE IMPACT ASSESSMENT: A GLOBAL PERSPECTIVE, II

    EPA Science Inventory

    Research within the field of Life Cycle Impact Assessment (LCIA) has greatly improved since the work of Heijungs and Guinee in 1992. Methodologies are currently available to address specific locations within North America, Europe, and Asia. Internationally, researchers are work...

  14. LCACCESS: PROMOTING THE USE OF LIFE CYCLE ASSESSMENT

    EPA Science Inventory

    Evaluating environmental impacts holistically from raw material acquisition, through manufacture, to use and disposal using a life cycle perspective is gradually being viewed by environmental managers and decision-makers as an important element in the tools that are used to achie...

  15. U.S. EPA'S RESEARCH ON LIFE-CYCLE ANALYSIS

    EPA Science Inventory

    Life-cycle analysis (LCA) consists of looking at a product, process or activity from its inception through its completion. or consumer products, this includes the stages of raw material acquisition, manufacturing and fabrication, distribution, consumer use/reuse and final disposa...

  16. Life Cycle Costs in Education: Operations & Maintenance Considered.

    ERIC Educational Resources Information Center

    Moussatche, Helena; Languell-Urquhart, Jennifer; Woodson, Carol

    2000-01-01

    Discusses life cycle cost analysis when deciding on flooring finishes and examines operations and maintenance cost effectiveness relative to hard, resilient, and soft flooring. A chart of evaluated flooring materials' characteristics, appropriate maintenance procedures, and recommended frequency is included. (GR)

  17. Monoclonal Antibodies to Intracellular Stages of Cryptosporidium parvum Define Life Cycle Progression In Vitro.

    PubMed

    Wilke, Georgia; Ravindran, Soumya; Funkhouser-Jones, Lisa; Barks, Jennifer; Wang, Qiuling; VanDussen, Kelli L; Stappenbeck, Thaddeus S; Kuhlenschmidt, Theresa B; Kuhlenschmidt, Mark S; Sibley, L David

    2018-06-27

    Among the obstacles hindering Cryptosporidium research is the lack of an in vitro culture system that supports complete life development and propagation. This major barrier has led to a shortage of widely available anti- Cryptosporidium antibodies and a lack of markers for staging developmental progression. Previously developed antibodies against Cryptosporidium were raised against extracellular stages or recombinant proteins, leading to antibodies with limited reactivity across the parasite life cycle. Here we sought to create antibodies that recognize novel epitopes that could be used to define intracellular development. We identified a mouse epithelial cell line that supported C. parvum growth, enabling immunization of mice with infected cells to create a bank of monoclonal antibodies (MAbs) against intracellular parasite stages while avoiding the development of host-specific antibodies. From this bank, we identified 12 antibodies with a range of reactivities across the parasite life cycle. Importantly, we identified specific MAbs that can distinguish different life cycle stages, such as trophozoites, merozoites, type I versus II meronts, and macrogamonts. These MAbs provide valuable tools for the Cryptosporidium research community and will facilitate future investigation into parasite biology. IMPORTANCE Cryptosporidium is a protozoan parasite that causes gastrointestinal disease in humans and animals. Currently, there is a limited array of antibodies available against the parasite, which hinders imaging studies and makes it difficult to visualize the parasite life cycle in different culture systems. In order to alleviate this reagent gap, we created a library of novel antibodies against the intracellular life cycle stages of Cryptosporidium We identified antibodies that recognize specific life cycle stages in distinctive ways, enabling unambiguous description of the parasite life cycle. These MAbs will aid future investigation into Cryptosporidium biology and

  18. Charting the Course: Life Cycle Management of Mars Mission Digital Information

    NASA Technical Reports Server (NTRS)

    Reiz, Julie M.

    2003-01-01

    This viewgraph presentation reviews the life cycle management of MER Project information. This process was an essential key to the successful launch of the MER Project rovers. Incorporating digital information archive requirements early in the project life cycle resulted in: Design of an information system that included archive metadata, Reduced the risk of information loss through in-process appraisal, Easier transfer of project information to institutional online archive and Project appreciation for preserving information for reuse by future projects

  19. From Centralized Disassembly to Life Cycle Management: Status and Progress of E-waste Treatment System in China

    NASA Astrophysics Data System (ADS)

    Song, Xiaolong; Yang, Jianxin; Lu, Bin; Yang, Dong

    2017-01-01

    China is now facing e-waste problems from both growing domestic generation and illegal imports. Many stakeholders are involved in the e-waste treatment system due to the complexity of e-waste life cycle. Beginning with the state of the e-waste treatment industry in China, this paper summarizes the latest progress in e-waste management from such aspects as the new edition of the China RoHS Directive, new Treatment List, new funding subsidy standard, and eco-design pilots. Thus, a conceptual model for life cycle management of e-waste is generalized. The operating procedure is to first identify the life cycle stages of the e-waste and extract the important life cycle information. Then, life cycle tools can be used to conduct a systematic analysis to help decide how to maximize the benefits from a series of life cycle engineering processes. Meanwhile, life cycle thinking is applied to improve the legislation relating to e-waste so as to continuously improve the sustainability of the e-waste treatment system. By providing an integrative framework, the life cycle management of e-waste should help to realize sustainable management of e-waste in developing countries.

  20. Advanced Launch Technology Life Cycle Analysis Using the Architectural Comparison Tool (ACT)

    NASA Technical Reports Server (NTRS)

    McCleskey, Carey M.

    2015-01-01

    Life cycle technology impact comparisons for nanolauncher technology concepts were performed using an Affordability Comparison Tool (ACT) prototype. Examined are cost drivers and whether technology investments can dramatically affect the life cycle characteristics. Primary among the selected applications was the prospect of improving nanolauncher systems. As a result, findings and conclusions are documented for ways of creating more productive and affordable nanolauncher systems; e.g., an Express Lane-Flex Lane concept is forwarded, and the beneficial effect of incorporating advanced integrated avionics is explored. Also, a Functional Systems Breakdown Structure (F-SBS) was developed to derive consistent definitions of the flight and ground systems for both system performance and life cycle analysis. Further, a comprehensive catalog of ground segment functions was created.

  1. The life cycle of a tornadic cloud as seen from a geosynchronous satellite

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Dodge, J. C.; Smith, R. E.

    1983-01-01

    The life span of a severe storm is on the order of a few hours. Rapid-scan infrared and visible observations from geosynchronous satellites can be useful for studying the life cycle of a severe convective storm. By using artificial colors for pixels representing blackbody temperatures of the cloud top, convective storms can be observed throughout their life cycles. In this paper clouds associated with a tornadic storm, the Ringwood, OK tornado on May 29, 1977, are compared with those without a tornadic storm to illustrate how the infrared and visible observations from a geosynchronous satellite can be used to study the differences in their life cycles. The instability of the air mass and the meteorological background are discussed based on balloon observations.

  2. Comparison of Battery Life Across Real-World Automotive Drive-Cycles (Presentation)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, K.; Earleywine, M.; Wood, E.

    2011-11-01

    Laboratories run around-the-clock aging tests to try to understand as quickly as possible how long new Li-ion battery designs will last under certain duty cycles. These tests may include factors such as duty cycles, climate, battery power profiles, and battery stress statistics. Such tests are generally accelerated and do not consider possible dwell time at high temperatures and states-of-charge. Battery life-predictive models provide guidance as to how long Li-ion batteries may last under real-world electric-drive vehicle applications. Worst-case aging scenarios are extracted from hundreds of real-world duty cycles developed from vehicle travel surveys. Vehicles examined included PHEV10 and PHEV40 EDVsmore » under fixed (28 degrees C), limited cooling (forced ambient temperature), and aggressive cooling (20 degrees C chilled liquid) scenarios using either nightly charging or opportunity charging. The results show that battery life expectancy is 7.8 - 13.2 years for the PHEV10 using a nightly charge in Phoenix, AZ (hot climate), and that the 'aggressive' cooling scenario can extend battery life by 1-3 years, while the 'limited' cooling scenario shortens battery life by 1-2 years. Frequent (opportunity) charging can reduce battery life by 1 year for the PHEV10, while frequent charging can extend battery life by one-half year.« less

  3. Terrrestrialization of isolated habitats

    NASA Astrophysics Data System (ADS)

    Kolodziejczyk, Agata; Harasymczuk, Matt; Foing, Bernard

    2017-04-01

    One of the most prominent issue for habitability of the solar system and beyond is to adjust a habitat for human life. Since the human life adapted to terrestrial environment during millions of years of evolution, terrestrialization of the base should be a natural trend strictly applied in habitat design. We discuss basic concerns about introducing biomimetic backup safety solutions such modularity, circularity, autonomy and plasticity into life support systems. Particularly we describe critical life processes such briefing, drinking, eating, homeostatic regulation, activity and sleep, in relation to symbiosis and competition with other species living together. Finally, we analyze ecological tolerance and transformation factors, which seem to be crucial in future habitability projects.

  4. Applying Movement Ecology to Marine Animals with Complex Life Cycles.

    PubMed

    Allen, Richard M; Metaxas, Anna; Snelgrove, Paul V R

    2018-01-03

    Marine animals with complex life cycles may move passively or actively for fertilization, dispersal, predator avoidance, resource acquisition, and migration, and over scales from micrometers to thousands of kilometers. This diversity has catalyzed idiosyncratic and unfocused research, creating unsound paradigms regarding the role of movement in ecology and evolution. The emerging movement ecology paradigm offers a framework to consolidate movement research independent of taxon, life-history stage, scale, or discipline. This review applies the framework to movement among life-history stages in marine animals with complex life cycles to consolidate marine movement research and offer insights for scientists working in aquatic and terrestrial realms. Irrespective of data collection or simulation strategy, breaking each life-history stage down into the fundamental units of movement allows each unit to be studied independently or interactively with other units. Understanding these underlying mechanisms of movement within each life-history stage can then be used to construct lifetime movement paths. These paths can allow further investigation of the relative contributions and interdependencies of steps and phases across a lifetime and how these paths influence larger research topics, such as population-level movements.

  5. Applying Movement Ecology to Marine Animals with Complex Life Cycles

    NASA Astrophysics Data System (ADS)

    Allen, Richard M.; Metaxas, Anna; Snelgrove, Paul V. R.

    2018-01-01

    Marine animals with complex life cycles may move passively or actively for fertilization, dispersal, predator avoidance, resource acquisition, and migration, and over scales from micrometers to thousands of kilometers. This diversity has catalyzed idiosyncratic and unfocused research, creating unsound paradigms regarding the role of movement in ecology and evolution. The emerging movement ecology paradigm offers a framework to consolidate movement research independent of taxon, life-history stage, scale, or discipline. This review applies the framework to movement among life-history stages in marine animals with complex life cycles to consolidate marine movement research and offer insights for scientists working in aquatic and terrestrial realms. Irrespective of data collection or simulation strategy, breaking each life-history stage down into the fundamental units of movement allows each unit to be studied independently or interactively with other units. Understanding these underlying mechanisms of movement within each life-history stage can then be used to construct lifetime movement paths. These paths can allow further investigation of the relative contributions and interdependencies of steps and phases across a lifetime and how these paths influence larger research topics, such as population-level movements.

  6. LIFE CYCLE IMPACT ASSESSMENT FOR INCREASING INDUSTRIAL SUSTAINABILITY

    EPA Science Inventory

    Life Cycle Impact Assessment (LCIA) can be a very useful decision support tool for assisting in environmental decision making to allow the pursuit of increasing sustainability. Increasing sustainability will be defined and presented as a more concrete and quantifiable goal when c...

  7. Life cycle greenhouse gas emissions of sugar cane renewable jet fuel.

    PubMed

    Moreira, Marcelo; Gurgel, Angelo C; Seabra, Joaquim E A

    2014-12-16

    This study evaluated the life cycle GHG emissions of a renewable jet fuel produced from sugar cane in Brazil under a consequential approach. The analysis included the direct and indirect emissions associated with sugar cane production and fuel processing, distribution, and use for a projected 2020 scenario. The CA-GREET model was used as the basic analytical tool, while Land Use Change (LUC) emissions were estimated employing the GTAP-BIO-ADV and AEZ-EF models. Feedstock production and LUC impacts were evaluated as the main sources of emissions, respectively estimated as 14.6 and 12 g CO2eq/MJ of biofuel in the base case. However, the renewable jet fuel would strongly benefit from bagasse and trash-based cogeneration, which would enable a net life cycle emission of 8.5 g CO2eq/MJ of biofuel in the base case, whereas Monte Carlo results indicate 21 ± 11 g CO2eq/MJ. Besides the major influence of the electricity surplus, the sensitivity analysis showed that the cropland-pasture yield elasticity and the choice of the land use factor employed to sugar cane are relevant parameters for the biofuel life cycle performance. Uncertainties about these estimations exist, especially because the study relies on projected performances, and further studies about LUC are also needed to improve the knowledge about their contribution to the renewable jet fuel life cycle.

  8. Survival of freezing by hydrated tardigrades inhabiting terrestrial and freshwater habitats.

    PubMed

    Guidetti, Roberto; Altiero, Tiziana; Bertolani, Roberto; Grazioso, Pasqualina; Rebecchi, Lorena

    2011-04-01

    The seasonality and unpredictability of environmental conditions at high altitudes and latitudes govern the life cycle patterns of organisms, giving rise to stresses that cause death or development of specific adaptations. Ice formation is a major variable affecting the survival of both freshwater fauna and fauna inhabiting lichens, mosses and leaf litter. Tardigrades occupy a wide range of niches in marine, freshwater and terrestrial environments. The highest number of species is found in terrestrial habitats thanks to their ability to enter anhydrobiosis and cryobiosis. The cryobiotic ability of tardigrade species from polar regions is well known. Consequently, we focused our research on the ability to survive freezing in the active hydrated state using seven tardigrade species differing in phylogenetic position and collected at various altitudes and from different habitats in a temperate area. Specimens were cooled at different cooling rates (from 0.31° C min(-1) to 3.26° C min(-1)). Even though the final survival and the time required by animals to recover to active life were both inversely related to the cooling rate, highly significant interspecific differences were found. Species survival ability ranged from excellent to none. Species living in xeric habitats withstood freezing better than those living in hygrophilous habitats, while true limnic species did not exhibit any cryobiotic ability. The ability to withstand freezing seems linked to the anhydrobiotic ability. The differences in cryptobiotic performance among tardigrade species seem more influenced by selective pressures linked to local adaptation to habitat characteristics than by phylogenetic relationships. Copyright © 2011 Elsevier GmbH. All rights reserved.

  9. Hybrid life-cycle assessment of natural gas based fuel chains for transportation.

    PubMed

    Strømman, Anders Hammer; Solli, Christian; Hertwich, Edgar G

    2006-04-15

    This research compares the use of natural gas, methanol, and hydrogen as transportation fuels. These three fuel chains start with the extraction and processing of natural gas in the Norwegian North Sea and end with final use in Central Europe. The end use is passenger transportation with a sub-compact car that has an internal combustion engine for the natural gas case and a fuel cell for the methanol and hydrogen cases. The life cycle assessment is performed by combining a process based life-cycle inventory with economic input-output data. The analysis shows that the potential climate impacts are lowest for the hydrogen fuel scenario with CO2 deposition. The hydrogen fuel chain scenario has no significant environmental disadvantage compared to the other fuel chains. Detailed analysis shows that the construction of the car contributes significantly to most impact categories. Finally, it is shown how the application of a hybrid inventory model ensures a more complete inventory description compared to standard process-based life-cycle assessment. This is particularly significant for car construction which would have been significantly underestimated in this study using standard process life-cycle assessment alone.

  10. Learning, Unlearning and Relearning--Knowledge Life Cycles in Library and Information Science Education

    ERIC Educational Resources Information Center

    Bedford, Denise A. D.

    2015-01-01

    The knowledge life cycle is applied to two core capabilities of library and information science (LIS) education--teaching, and research and development. The knowledge claim validation, invalidation and integration steps of the knowledge life cycle are translated to learning, unlearning and relearning processes. Mixed methods are used to determine…

  11. A deterministic model of nettle caterpillar life cycle

    NASA Astrophysics Data System (ADS)

    Syukriyah, Y.; Nuraini, N.; Handayani, D.

    2018-03-01

    Palm oil is an excellent product in the plantation sector in Indonesia. The level of palm oil productivity is very potential to increase every year. However, the level of palm oil productivity is lower than its potential. Pests and diseases are the main factors that can reduce production levels by up to 40%. The existence of pests in plants can be caused by various factors, so the anticipation in controlling pest attacks should be prepared as early as possible. Caterpillars are the main pests in oil palm. The nettle caterpillars are leaf eaters that can significantly decrease palm productivity. We construct a deterministic model that describes the life cycle of the caterpillar and its mitigation by using a caterpillar predator. The equilibrium points of the model are analyzed. The numerical simulations are constructed to give a representation how the predator as the natural enemies affects the nettle caterpillar life cycle.

  12. Transcriptome analyses of the Giardia lamblia life cycle

    PubMed Central

    Birkeland, Shanda R.; Preheim, Sarah P.; Davids, Barbara J.; Cipriano, Michael J.; Palm, Daniel; Reiner, David S.; Svärd, Staffan G.; Gillin, Frances D.; McArthur, Andrew G.

    2010-01-01

    We quantified mRNA abundance from 10 stages in the Giardia lamblia life cycle in vitro using Serial Analysis of Gene Expression (SAGE). 163 abundant transcripts were expressed constitutively. 71 transcripts were upregulated specifically during excystation and 42 during encystation. Nonetheless, the transcriptomes of cysts and trophozoites showed major differences. SAGE detected co-expressed clusters of 284 transcripts differentially expressed in cysts and excyzoites and 287 transcripts in vegetative trophozoites and encysting cells. All clusters included known genes and pathways as well as proteins unique to Giardia or diplomonads. SAGE analysis of the Giardia life cycle identified a number of kinases, phosphatases, and DNA replication proteins involved in excystation and encystation, which could be important for examining the roles of cell signaling in giardial differentiation. Overall, these data pave the way for directed gene discovery and a better understanding of the biology of Giardia lamblia. PMID:20570699

  13. Method and apparatus for bio-regenerative life support system

    NASA Technical Reports Server (NTRS)

    Cullingford, Hatice S. (Inventor)

    1991-01-01

    A life support system is disclosed for human habitation (cabin) which has a bioregenerative capability through the use of a plant habitat (greenhouse) whereby oxygen-rich air from the greenhouse is processed and used in the cabin and carbon dioxide-rich air from the cabin is used in the greenhouse. Moisture from the air of both cabin and greenhouse is processed and reused in both. Wash water from the cabin is processed and reused in the cabin as hygiene water, and urine from the cabin is processed and used in the greenhouse. Spent water from the greenhouse is processed and reused in the greenhouse. Portions of the processing cycles are separated between cabin and greenhouse in order to reduce to a minimum cross contamination of the two habitat systems. Other portions of the processing cycles are common to both cabin and greenhouse. The use of bioregenerative techniques permits a substantial reduction of the total consumables used by the life support system.

  14. History of the discovery of the life cycle of Toxoplasma gondii.

    PubMed

    Dubey, J P

    2009-07-01

    It has been 100 years since the discovery of Toxoplasma gondii in 1908. Its full life cycle was not discovered until 1970 when it was found that it is a coccidian parasite of cats with all non-feline warm blooded animals (including humans) as intermediate hosts. The discovery of the environmentally resistant stage of the parasite, the oocyst, made it possible to explain its worldwide prevalence. In the present paper, events associated with the discovery of its life cycle are recalled.

  15. LIFE CYCLE DESIGN FRAMEWORK AND DEMONSTRATION PROJECTS - PROFILES OF AT&T AND ALLIED SIGNAL

    EPA Science Inventory

    This document offers guidance and practical experience for integrating environmental considerations into product system development. Life cycle design seeks to minimize the environmental burden associated with a product's life cycle from raw materials acquisition through manufact...

  16. Integrated design strategy for product life-cycle management

    NASA Astrophysics Data System (ADS)

    Johnson, G. Patrick

    2001-02-01

    Two major trends suggest new considerations for environmentally conscious manufacturing (ECM) -- the continuation of dematerialization and the growing trend toward goods becoming services. A diversity of existing research could be integrated around those trends in ways that can enhance ECM. Major research-based achievements in information, computation, and communications systems, sophisticated and inexpensive sensing capabilities, highly automated and precise manufacturing technologies, and new materials continue to drive the phenomenon of dematerialization - the reduction of the material and energy content of per capita GDP. Knowledge is also growing about the sociology, economics, mathematics, management and organization of complex socio-economic systems. And that has driven a trend towards goods evolving into services. But even with these significant trends, the value of material, energy, information and human resources incorporated into the manufacture, use and disposal of modern products and services often far exceeds the benefits realized. Multi-disciplinary research integrating these drivers with advances in ECM concepts could be the basis for a new strategy of production. It is argued that a strategy of integrating information resources with physical and human resources over product life cycles, together with considering products as streams of service over time, could lead to significant economic payoff. That strategy leads to an overall design concept to minimize costs of all resources over the product life cycle to more fully capture benefits of all resources incorporated into modern products. It is possible by including life cycle monitoring, periodic component replacement, re-manufacture, salvage and human factor skill enhancement into initial design.

  17. Life cycle assessment of electronic waste treatment.

    PubMed

    Hong, Jinglan; Shi, Wenxiao; Wang, Yutao; Chen, Wei; Li, Xiangzhi

    2015-04-01

    Life cycle assessment was conducted to estimate the environmental impact of electronic waste (e-waste) treatment. E-waste recycling with an end-life disposal scenario is environmentally beneficial because of the low environmental burden generated from human toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, and marine ecotoxicity categories. Landfill and incineration technologies have a lower and higher environmental burden than the e-waste recycling with an end-life disposal scenario, respectively. The key factors in reducing the overall environmental impact of e-waste recycling are optimizing energy consumption efficiency, reducing wastewater and solid waste effluent, increasing proper e-waste treatment amount, avoiding e-waste disposal to landfill and incineration sites, and clearly defining the duties of all stakeholders (e.g., manufacturers, retailers, recycling companies, and consumers). Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Ontology for Life-Cycle Modeling of Water Distribution Systems: Model View Definition

    DTIC Science & Technology

    2013-06-01

    Research and Development Center, Construction Engineering Research Laboratory (ERDC-CERL) to develop a life-cycle building model have resulted in the...Laboratory (ERDC-CERL) to develop a life-cycle building model have resulted in the definition of a “core” building information model that contains...developed experimental BIM models us- ing commercial off-the-shelf (COTS) software. Those models represent three types of typical low-rise Army

  19. Alternative Approaches to the Family Life Cycle in the Analysis of Housing Consumption.

    ERIC Educational Resources Information Center

    McLeod, P. B.; Ellis, J. R.

    1983-01-01

    Used loan-approval data to analyze the effects of life-cycle stage on housing consumption. The detailed typologies were not generally superior to the more simplified approaches, except for per capita consumption. For per capita consumption, price, and quality, clear evidence is found for structural nonhomogeneity across life-cycle stages. (JAC)

  20. [Life cycle assessment of energy consumption and greenhouse gas emissions of cellulosic ethanol from corn stover].

    PubMed

    Tian, Wang; Liao, Cuiping; Li, Li; Zhao, Daiqing

    2011-03-01

    Life Cycle Assessment (LCA) is the only standardized tool currently used to assess environmental loads of products and processes. The life cycle analysis, as a part of LCA, is a useful and powerful methodology for studying life cycle energy efficiency and life cycle GHG emission. To quantitatively explain the potential of energy saving and greenhouse gas (GHG) emissions reduction of corn stover-based ethanol, we analyzed life cycle energy consumption and GHG emissions of corn stover-based ethanol by the method of life cycle analysis. The processes are dilute acid prehydrolysis and enzymatic hydrolysis. The functional unit was defined as 1 km distance driven by the vehicle. Results indicated: compared with gasoline, the corn stover-based E100 (100% ethanol) and E10 (a blend of 10% ethanol and 90% gasoline by volume) could reduce life cycle fossil energy consumption by 79.63% and 6.25% respectively, as well as GHG emissions by 53.98% and 6.69%; the fossil energy consumed by biomass stage was 68.3% of total fossil energy input, N-fertilizer and diesel were the main factors which contributed 45.78% and 33.26% to biomass stage; electricity production process contributed 42.06% to the net GHG emissions, the improvement of technology might reduce emissions markedly.

  1. LIFE CYCLE DESIGN OF IN-MOLD SURFACING FILM

    EPA Science Inventory

    Since 1990, the NRMRL has been at the forefront in the development of Life Cycle Assessment as a methodology for environmental assessment. In 1994, NRMRL established an LCA Team to organize individual efforts into a comprehensive research program. The LCA Team coordinates work in...

  2. A comparison of major petroleum life cycle models

    EPA Science Inventory

    Many organizations have attempted to develop an accurate well-to-pump life cycle model of petroleum products in order to inform decision makers of the consequences of its use. Our paper studies five of these models, demonstrating the differences in their predictions and attemptin...

  3. Gamma Radiation Sterilization Reduces the High-cycle Fatigue Life of Allograft Bone.

    PubMed

    Islam, Anowarul; Chapin, Katherine; Moore, Emily; Ford, Joel; Rimnac, Clare; Akkus, Ozan

    2016-03-01

    Sterilization by gamma radiation impairs the mechanical properties of bone allografts. Previous work related to radiation-induced embrittlement of bone tissue has been limited mostly to monotonic testing which does not necessarily predict the high-cycle fatigue life of allografts in vivo. We designed a custom rotating-bending fatigue device to answer the following questions: (1) Does gamma radiation sterilization affect the high-cycle fatigue behavior of cortical bone; and (2) how does the fatigue life change with cyclic stress level? The high-cycle fatigue behavior of human cortical bone specimens was examined at stress levels related to physiologic levels using a custom-designed rotating-bending fatigue device. Test specimens were distributed among two treatment groups (n = 6/group); control and irradiated. Samples were tested until failure at stress levels of 25, 35, and 45 MPa. At 25 MPa, 83% of control samples survived 30 million cycles (run-out) whereas 83% of irradiated samples survived only 0.5 million cycles. At 35 MPa, irradiated samples showed an approximately 19-fold reduction in fatigue life compared with control samples (12.2 × 10(6) ± 12.3 × 10(6) versus 6.38 × 10(5) ± 6.81 × 10(5); p = 0.046), and in the case of 45 MPa, this reduction was approximately 17.5-fold (7.31 × 10(5) ± 6.39 × 10(5) versus 4.17 × 10(4) ± 1.91 × 10(4); p = 0.025). Equations to estimate high-cycle fatigue life of irradiated and control cortical bone allograft at a certain stress level were derived. Gamma radiation sterilization severely impairs the high cycle fatigue life of structural allograft bone tissues, more so than the decline that has been reported for monotonic mechanical properties. Therefore, clinicians need to be conservative in the expectation of the fatigue life of structural allograft bone tissues. Methods to preserve the fatigue strength of nonirradiated allograft bone tissue are needed. As opposed to what monotonic tests might suggest, the cyclic

  4. The Life Cycle of Images: Revisiting the Ethical Treatment of the Art Therapy Image

    ERIC Educational Resources Information Center

    Hinz, Lisa D.

    2013-01-01

    Using the metaphor of the human life cycle, the author of this viewpoint suggests that consideration of the birth, life, and death of images made in art therapy may promote a new perspective on their ethical treatment. A developmental view of images encourages art therapists to see art images as living entities that undergo a natural life cycle.…

  5. Life cycle greenhouse gas emissions and freshwater consumption associated with Bakken tight oil

    PubMed Central

    Laurenzi, Ian J.; Bergerson, Joule A.; Motazedi, Kavan

    2016-01-01

    In recent years, hydraulic fracturing and horizontal drilling have been applied to extract crude oil from tight reservoirs, including the Bakken formation. There is growing interest in understanding the greenhouse gas (GHG) emissions associated with the development of tight oil. We conducted a life cycle assessment of Bakken crude using data from operations throughout the supply chain, including drilling and completion, refining, and use of refined products. If associated gas is gathered throughout the Bakken well life cycle, then the well to wheel GHG emissions are estimated to be 89 g CO2eq/MJ (80% CI, 87–94) of Bakken-derived gasoline and 90 g CO2eq/MJ (80% CI, 88–94) of diesel. If associated gas is flared for the first 12 mo of production, then life cycle GHG emissions increase by 5% on average. Regardless of the level of flaring, the Bakken life cycle GHG emissions are comparable to those of other crudes refined in the United States because flaring GHG emissions are largely offset at the refinery due to the physical properties of this tight oil. We also assessed the life cycle freshwater consumptions of Bakken-derived gasoline and diesel to be 1.14 (80% CI, 0.67–2.15) and 1.22 barrel/barrel (80% CI, 0.71–2.29), respectively, 13% of which is associated with hydraulic fracturing. PMID:27849573

  6. An examination of silver nanoparticles in socks using screening-level life cycle assessment

    NASA Astrophysics Data System (ADS)

    Meyer, David E.; Curran, Mary Ann; Gonzalez, Michael A.

    2011-01-01

    Screening-level life cycle assessment (LCA) can provide a quick tool to identify the life cycle hot spots and focus research efforts to help to minimize the burdens of a technology while maximizing its benefits. The use of nanoscale silver in consumer products has exploded in popularity. Although its use is considered beneficial because of antimicrobial effects, some attention must be given to the potential environmental impacts it could impart on the life cycle of these nanoproducts as production demands escalate. This work examines the environmental impact of including silver nanoparticles in commercially available socks using screening-level LCA. Initial results suggest washing during the use phase contributes substantially more than the manufacturing phase to the product life cycle impacts. Comparison of nanoparticles prepared by either chemical reduction, liquid flame spray (LFS), or plasma arc demonstrate how the type of manufacturing process used for the nanoscale silver can change the resulting life cycle impact of the sock product. The magnitude of this impact will depend on the type of process used to manufacture the nanoscale silver, with LFS having the most impact because of the need for large quantities of hydrogen and oxygen. Although the increased impacts for a single nanoproduct may be relatively small, the added environmental load can actually be a significant quantity when considered at the regional or global production level.

  7. Time-dependent Variation in Life Cycle Assessment of Microalgal Biorefinery Co-products

    NASA Astrophysics Data System (ADS)

    Montazeri, Mahdokht

    Microalgae can serve as a highly productive biological feedstock for fuels and chemicals. The lipid fraction of algal seeds has been the primary target of research for biofuel production. However, numerous assessments have found that valorization of co-products is essential to achieve economic and environmental goals. The relative proportion of co-products depends on the biomolecular composition of algae at the time of harvesting. In the present study the productivity of lipid, starch, and protein fractions were shown through growth experiments to vary widely with species, feeding regime, and harvesting time. Four algae species were cultivated under nitrogen-replete and -deplete conditions and analyzed at regular harvesting intervals. Dynamic growth results were then used for life cycle assessment using the U.S. Department of Energy's GREET model to determine optimal growth scenarios that minimize life cycle greenhouse gas (GHG) emissions, eutrophication, and cumulative energy demand (CED), while aiming for an energy return on investment (EROI) greater than unity. Per kg of biodiesel produced, C. sorokiniana in N-replete conditions harvested at 12 days was most favorable for GHG emissions and CED, despite having a lipid content of <20%. N. oculata under the same conditions had the lowest life cycle eutrophication impacts, driven by efficient nutrient cycling and valorization of microalgal protein and anaerobic digester residue co-products. The results indicate that growth cycle times that maximize a single fraction do not necessarily result in the most favorable environmental performance on a life cycle basis, underscoring the importance of designing biorefinery systems that simultaneously optimize for lipid and non-lipid fractions.

  8. The influence of catalysts on biofuel life cycle analysis (LCA)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Benavides, Pahola Thathiana; Cronauer, Donald C.; Adom, Felix K.

    Catalysts play an important role in biofuel production but are rarely included in biofuel life cycle analysis (LCA). In this work, we estimate the cradle-to-gate energy consumption and greenhouse gas (GHG) emissions of Pt/γ-Al 2O 3, CoMo/γ-Al 2O 3, and ZSM-5, catalysts that could be used in processes to convert biomass to biofuels. We also consider the potential impacts of catalyst recovery and recycling. Integrating the energy and environmental impacts of CoMo/γ-Al 2O 3 and ZSM-5 into an LCA of renewable gasoline produced via in-situ and ex-situ fast pyrolysis of a blended woody feedstock revealed that the ZSM-5, with cradle-to-gatemore » GHG emissions of 7.7 kg CO 2e/kg, could influence net life-cycle GHG emissions of the renewable gasoline (1.7 gCO 2e/MJ for the in-situ process, 1.2 gCO 2e/MJ for the ex-situ process) by up to 14% depending on the loading rate. CoMo/γ-Al 2O 3 had a greater GHG intensity (9.6 kg CO 2e/kg) than ZSM-5, however, it contributed approximately only 1% to the life-cycle GHG emissions of the renewable gasoline because of the small amount of this catalyst needed per kg of biofuel produced. As a result, given that catalysts can contribute significantly to biofuel life-cycle GHG emissions depending on the GHG intensity of their production and their consumption rates, biofuel LCAs should consider the potential influence of catalysts on LCA results.« less

  9. The influence of catalysts on biofuel life cycle analysis (LCA)

    DOE PAGES

    Benavides, Pahola Thathiana; Cronauer, Donald C.; Adom, Felix K.; ...

    2017-01-21

    Catalysts play an important role in biofuel production but are rarely included in biofuel life cycle analysis (LCA). In this work, we estimate the cradle-to-gate energy consumption and greenhouse gas (GHG) emissions of Pt/γ-Al 2O 3, CoMo/γ-Al 2O 3, and ZSM-5, catalysts that could be used in processes to convert biomass to biofuels. We also consider the potential impacts of catalyst recovery and recycling. Integrating the energy and environmental impacts of CoMo/γ-Al 2O 3 and ZSM-5 into an LCA of renewable gasoline produced via in-situ and ex-situ fast pyrolysis of a blended woody feedstock revealed that the ZSM-5, with cradle-to-gatemore » GHG emissions of 7.7 kg CO 2e/kg, could influence net life-cycle GHG emissions of the renewable gasoline (1.7 gCO 2e/MJ for the in-situ process, 1.2 gCO 2e/MJ for the ex-situ process) by up to 14% depending on the loading rate. CoMo/γ-Al 2O 3 had a greater GHG intensity (9.6 kg CO 2e/kg) than ZSM-5, however, it contributed approximately only 1% to the life-cycle GHG emissions of the renewable gasoline because of the small amount of this catalyst needed per kg of biofuel produced. As a result, given that catalysts can contribute significantly to biofuel life-cycle GHG emissions depending on the GHG intensity of their production and their consumption rates, biofuel LCAs should consider the potential influence of catalysts on LCA results.« less

  10. 1977 Nationwide Personal Transportation Study : a life cycle of travel by the American family

    DOT National Transportation Integrated Search

    1981-07-01

    This report provides information about family trips and travel from the point of view of the family life cycle, using data from the 1977 Nationwide Personal Transportation Study. Daily travel characteristics of families in stages of four life cycles ...

  11. Life-Cycle Cost/Benefit Assessment of Expedite Departure Path (EDP)

    NASA Technical Reports Server (NTRS)

    Wang, Jianzhong Jay; Chang, Paul; Datta, Koushik

    2005-01-01

    This report presents a life-cycle cost/benefit assessment (LCCBA) of Expedite Departure Path (EDP), an air traffic control Decision Support Tool (DST) currently under development at NASA. This assessment is an update of a previous study performed by bd Systems, Inc. (bd) during FY01, with the following revisions: The life-cycle cost assessment methodology developed by bd for the previous study was refined and calibrated using Free Flight Phase 1 (FFP1) cost information for Traffic Management Advisor (TMA, or TMA-SC in the FAA's terminology). Adjustments were also made to the site selection and deployment scheduling methodology to include airspace complexity as a factor. This technique was also applied to the benefit extrapolation methodology to better estimate potential benefits for other years, and at other sites. This study employed a new benefit estimating methodology because bd s previous single year potential benefit assessment of EDP used unrealistic assumptions that resulted in optimistic estimates. This methodology uses an air traffic simulation approach to reasonably predict the impacts from the implementation of EDP. The results of the costs and benefits analyses were then integrated into a life-cycle cost/benefit assessment.

  12. Life Cycle Assessment of III-V Precursors for Photovoltaic and Semiconductor Applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Horowitz, Kelsey A; Smith, Brittany L.; Babbitt, Callie W.

    This study provides detailed information on the manufacture of III-V metal organic vapor phase epitaxy precursors through extensive literature and patent research. This data informed a cradle-to-gate life cycle assessment of these chemicals. Reported impacts include cumulative energy demand and greenhouse gas emissions. The results were interpreted to identify sources of environmental burden within the life cycle and were compared to energy demand reported in previous studies.

  13. Achieving Our Environmental Sustainability Goals: The Opportunities and Pitfalls of Applying Life Cycle Thinking

    EPA Science Inventory

    An increasing number of people around the world are beginning to realize that a systems approach, such as life cycle thinking, is necessary to truly achieve environmental sustainability. Without the holistic perspective that life cycle thinking provides, our actions risk leading ...

  14. Use of Life Cycle Assessment in Environmental Management

    NASA Astrophysics Data System (ADS)

    Ross, Stuart; Evans, David

    2002-01-01

    The aim of this paper is to demonstrate how life cycle assessment (LCA) can be used to develop strategic policies that can lead to a minimization of the environmental burden resulting from the provision of services or the manufacture, use, and disposal of products within the economy. We accomplish this aim by presenting a case study that evaluates the greenhouse gas contributions of each stage in the life cycle of containerboard packaging and the potential impact on emissions of various policy options available to decision-makers. Our analysis showed that, in general, the most useful strategy was to recycle the used packaging. However, our analysis also indicated that when measures are taken to eliminate sources of methane emissions, then recycling is no longer beneficial from a greenhouse perspective. This is because the process energy required in the form of gas and electricity is substantially greater for containerboard manufactured from recycled material than it is for virgin fiber.

  15. 77 FR 50724 - Developing Software Life Cycle Processes for Digital Computer Software Used in Safety Systems of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-22

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Developing Software Life Cycle Processes for Digital... Software Life Cycle Processes for Digital Computer Software used in Safety Systems of Nuclear Power Plants... clarifications, the enhanced consensus practices for developing software life-cycle processes for digital...

  16. Increase Return on Investment of Software Development Life Cycle by Managing the Risk - A Case Study

    DTIC Science & Technology

    2015-04-01

    for increasing the return on investment during the Software Development Life Cycle ( SDLC ) through selected quantitative analyses employing both the...defect rate, return on investment (ROI), software development life cycle ( SDLC ) DE FE N SE A C Q U IS IT IO N UN IVERSITY ALU M N I A SSO C IATIO N R...becomes comfortable due to its intricacies and learning cycle. The same may be said with respect to software development life cycle ( SDLC ) management

  17. A life cycle cost economics model for projects with uniformly varying operating costs. [management planning

    NASA Technical Reports Server (NTRS)

    Remer, D. S.

    1977-01-01

    A mathematical model is developed for calculating the life cycle costs for a project where the operating costs increase or decrease in a linear manner with time. The life cycle cost is shown to be a function of the investment costs, initial operating costs, operating cost gradient, project life time, interest rate for capital and salvage value. The results show that the life cycle cost for a project can be grossly underestimated (or overestimated) if the operating costs increase (or decrease) uniformly over time rather than being constant as is often assumed in project economic evaluations. The following range of variables is examined: (1) project life from 2 to 30 years; (2) interest rate from 0 to 15 percent per year; and (3) operating cost gradient from 5 to 90 percent of the initial operating costs. A numerical example plus tables and graphs is given to help calculate project life cycle costs over a wide range of variables.

  18. Modeling the Ebolavirus Life Cycle with Transcription and Replication-Competent Viruslike Particle Assays.

    PubMed

    Biedenkopf, Nadine; Hoenen, Thomas

    2017-01-01

    Ebolaviruses are the causative agent of a severe hemorrhagic fever with high case fatality rates, for which no approved specific therapy is available. As biosafety level 4 (BSL4) agents, work with live ebolaviruses is restricted to maximum containment laboratories. Transcription and replication-competent viruslike particle (trVLP) systems are reverse genetics-based life cycle modeling systems that allow researchers to model virtually the entire ebolavirus life cycle outside of a maximum containment laboratory. These systems can be used to dissect the virus life cycle, and thus increase our understanding of virus biology, as well as for more applied uses such as the screening and development of novel antivirals, and thus represent powerful tools for work on ebolaviruses.

  19. Development and application of basis database for materials life cycle assessment in china

    NASA Astrophysics Data System (ADS)

    Li, Xiaoqing; Gong, Xianzheng; Liu, Yu

    2017-03-01

    As the data intensive method, high quality environmental burden data is an important premise of carrying out materials life cycle assessment (MLCA), and the reliability of data directly influences the reliability of the assessment results and its application performance. Therefore, building Chinese MLCA database is the basic data needs and technical supports for carrying out and improving LCA practice. Firstly, some new progress on database which related to materials life cycle assessment research and development are introduced. Secondly, according to requirement of ISO 14040 series standards, the database framework and main datasets of the materials life cycle assessment are studied. Thirdly, MLCA data platform based on big data is developed. Finally, the future research works were proposed and discussed.

  20. Insulation Cork Boards-Environmental Life Cycle Assessment of an Organic Construction Material.

    PubMed

    Silvestre, José D; Pargana, Nuno; de Brito, Jorge; Pinheiro, Manuel D; Durão, Vera

    2016-05-20

    Envelope insulation is a relevant technical solution to cut energy consumption and reduce environmental impacts in buildings. Insulation Cork Boards (ICB) are a natural thermal insulation material whose production promotes the recycling of agricultural waste. The aim of this paper is to determine and evaluate the environmental impacts of the production, use, and end-of-life processing of ICB. A "cradle-to-cradle" environmental Life Cycle Assessment (LCA) was performed according to International LCA standards and the European standards on the environmental evaluation of buildings. These results were based on site-specific data and resulted from a consistent methodology, fully described in the paper for each life cycle stage: Cork oak tree growth, ICB production, and end-of-life processing-modeling of the carbon flows ( i.e. , uptakes and emissions), including sensitivity analysis of this procedure; at the production stage-the modeling of energy processes and a sensitivity analysis of the allocation procedures; during building operation-the expected service life of ICB; an analysis concerning the need to consider the thermal diffusivity of ICB in the comparison of the performance of insulation materials. This paper presents the up-to-date "cradle-to-cradle" environmental performance of ICB for the environmental categories and life-cycle stages defined in European standards.

  1. Insulation Cork Boards—Environmental Life Cycle Assessment of an Organic Construction Material

    PubMed Central

    Silvestre, José D.; Pargana, Nuno; de Brito, Jorge; Pinheiro, Manuel D.; Durão, Vera

    2016-01-01

    Envelope insulation is a relevant technical solution to cut energy consumption and reduce environmental impacts in buildings. Insulation Cork Boards (ICB) are a natural thermal insulation material whose production promotes the recycling of agricultural waste. The aim of this paper is to determine and evaluate the environmental impacts of the production, use, and end-of-life processing of ICB. A “cradle-to-cradle” environmental Life Cycle Assessment (LCA) was performed according to International LCA standards and the European standards on the environmental evaluation of buildings. These results were based on site-specific data and resulted from a consistent methodology, fully described in the paper for each life cycle stage: Cork oak tree growth, ICB production, and end-of-life processing-modeling of the carbon flows (i.e., uptakes and emissions), including sensitivity analysis of this procedure; at the production stage—the modeling of energy processes and a sensitivity analysis of the allocation procedures; during building operation—the expected service life of ICB; an analysis concerning the need to consider the thermal diffusivity of ICB in the comparison of the performance of insulation materials. This paper presents the up-to-date “cradle-to-cradle” environmental performance of ICB for the environmental categories and life-cycle stages defined in European standards. PMID:28773516

  2. Life cycle of cytosolic prions.

    PubMed

    Hofmann, Julia; Vorberg, Ina

    2013-01-01

    Prions are self-templating protein aggregates that were originally identified as the causative agent of prion diseases in mammals, but have since been discovered in other kingdoms. Mammalian prions represent a unique class of infectious agents that are composed of misfolded prion protein. Prion proteins usually exist as soluble proteins but can refold and assemble into highly ordered, self-propagating prion polymers. The prion concept is also applicable to a growing number of non-Mendelian elements of inheritance in lower eukaryotes. While prions identified in mammals are clearly pathogens, prions in lower eukaryotes can be either detrimental or beneficial to the host. Prion phenotypes in fungi are transmitted vertically from mother to daughter cells during cell division and horizontally during mating or abortive mating, but extracellular phases have not been reported. Recent findings now demonstrate that in a mammalian cell environment, protein aggregates derived from yeast prion domains exhibit a prion life cycle similar to mammalian prions propagated ex vivo. This life cycle includes a soluble state of the protein, an induction phase by exogenous prion fibrils, stable replication of prion entities, vertical transmission to progeny and natural horizontal transmission to neighboring cells. Our data reveal that mammalian cells contain all co-factors required for cytosolic prion propagation and dissemination. This has important implications for understanding prion-like properties of disease-related protein aggregates. In light of the growing number of identified functional amyloids, cell-to-cell propagation of cytosolic protein conformers might not only be relevant for the spreading of disease-associated proteins, but might also be of more general relevance under non-disease conditions.

  3. Characterizing model uncertainties in the life cycle of lignocellulose-based ethanol fuels.

    PubMed

    Spatari, Sabrina; MacLean, Heather L

    2010-11-15

    Renewable and low carbon fuel standards being developed at federal and state levels require an estimation of the life cycle carbon intensity (LCCI) of candidate fuels that can substitute for gasoline, such as second generation bioethanol. Estimating the LCCI of such fuels with a high degree of confidence requires the use of probabilistic methods to account for known sources of uncertainty. We construct life cycle models for the bioconversion of agricultural residue (corn stover) and energy crops (switchgrass) and explicitly examine uncertainty using Monte Carlo simulation. Using statistical methods to identify significant model variables from public data sets and Aspen Plus chemical process models,we estimate stochastic life cycle greenhouse gas (GHG) emissions for the two feedstocks combined with two promising fuel conversion technologies. The approach can be generalized to other biofuel systems. Our results show potentially high and uncertain GHG emissions for switchgrass-ethanol due to uncertain CO₂ flux from land use change and N₂O flux from N fertilizer. However, corn stover-ethanol,with its low-in-magnitude, tight-in-spread LCCI distribution, shows considerable promise for reducing life cycle GHG emissions relative to gasoline and corn-ethanol. Coproducts are important for reducing the LCCI of all ethanol fuels we examine.

  4. Comparative life cycle assessment of disposable and reusable laryngeal mask airways.

    PubMed

    Eckelman, Matthew; Mosher, Margo; Gonzalez, Andres; Sherman, Jodi

    2012-05-01

    Growing awareness of the negative impacts from the practice of health care on the environment and public health calls for the routine inclusion of life cycle criteria into the decision-making process of device selection. Here we present a life cycle assessment of 2 laryngeal mask airways (LMAs), a one-time-use disposable Unique™ LMA and a 40-time-use reusable Classic™ LMA. In life cycle assessment, the basis of comparison is called the "functional unit." For this report, the functional unit of the disposable and reusable LMAs was taken to be maintenance of airway patency by 40 disposable LMAs or 40 uses of 1 reusable LMA. This was a cradle-to-grave study that included inputs and outputs for the manufacture, transport, use, and waste phases of the LMAs. The environmental impacts of the 2 LMAs were estimated using SimaPro life cycle assessment software and the Building for Environmental and Economic Sustainability impact assessment method. Sensitivity and simple life cycle cost analyses were conducted to aid in interpretation of the results. The reusable LMA was found to have a more favorable environmental profile than the disposable LMA as used at Yale New Haven Hospital. The most important sources of impacts for the disposable LMA were the production of polymers, packaging, and waste management, whereas for the reusable LMA, washing and sterilization dominated for most impact categories. The differences in environmental impacts between these devices strongly favor reusable devices. These benefits must be weighed against concerns regarding transmission of infection. Health care facilities can decrease their environmental impacts by using reusable LMAs, to a lesser extent by selecting disposable LMA models that are not made of certain plastics, and by ordering in bulk from local distributors. Certain practices would further reduce the environmental impacts of reusable LMAs, such as increasing the number of devices autoclaved in a single cycle to 10 (-25% GHG

  5. DEVELOPMENT OF THE METHOD AND U.S. NORMALIZATION DATABASE FOR LIFE CYCLE IMPACT ASSESSMENT AND SUSTAINABILITY METRICS

    EPA Science Inventory

    Normalization is an optional step within Life Cycle Impact Assessment (LCIA) that may be used to assist in the interpretation of life cycle inventory data as well as, life cycle impact assessment results. Normalization transforms the magnitude of LCI and LCIA results into relati...

  6. Making the Mark: The Role of Adenosine Modifications in the Life Cycle of RNA Viruses.

    PubMed

    Gonzales-van Horn, Sarah R; Sarnow, Peter

    2017-06-14

    Viral epitranscriptomics is a newly emerging field that has identified unique roles for RNA modifications in modulating life cycles of RNA viruses. Despite the observation of a handful of modified viral RNAs five decades ago, very little was known about how these modifications regulate viral life cycles, until recently. Here we review the pro- and anti-viral effects of methyl-6-adenosine in distinct viral life cycles, the role of 2' O-methyl modifications in RNA stability and innate immune sensing, and functions of adenosine to inosine modifications in retroviral life cycles. With roles for over 100 modifications in RNA still unknown, this is a rapidly emerging field that is destined to suggest novel antiviral therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Life Cycle Cost Analysis of Portland Cement Concrete Pavements

    DOT National Transportation Integrated Search

    1999-09-01

    This report describes the development of a new life cycle cost analysis methodology for Portland cement concrete pavements - one that considers all aspects of pavement design, construction, maintenance, and user impacts throughout the analysis period...

  8. Life Cycle Assessment as an Environmental Management Tool

    EPA Science Inventory

    Listed by Time Magazine as the method behind calculating “Ecological Intelligence,” one of “10 Ideas Changing the World Right Now” (March 23, 2009), Life Cycle Assessment (LCA) is the tool that is used to understand the environmental impacts of the products we make and sell. Jo...

  9. Microbial ecology of extreme environments: Antarctic dry valley yeasts and growth in substrate limited habitats

    NASA Technical Reports Server (NTRS)

    Vishniac, H. S.

    1981-01-01

    The multiple stresses temperature, moisture, and for chemoheterotrophs, sources of carbon and energy of the Dry Valley Antarctica soils allow at best depauperate communities, low in species diversity and population density. The nature of community structure, the operation of biogeochemical cycles, the evolution and mechanisms of adaptation to this habitat are of interest in informing speculations upon life on other planets as well as in modeling the limits of gene life. Yeasts of the Cryptococcus vishniacil complex (Basidiobiastomycetes) are investigated, as the only known indigenes of the most hostile, lichen free, parts of the Dry Valleys. Methods were developed for isolating these yeasts (methods which do not exclude the recovery of other microbiota). The definition of the complex was refined and the importance of nitrogen sources was established as well as substrate competition in fitness to the Dry Valley habitats.

  10. From concept(ion) to life after death/the grave: The 'natural' history and life cycle(s) of novel psychoactive substances (NPS).

    PubMed

    Corkery, John Martin; Orsolini, Laura; Papanti, Duccio; Schifano, Fabrizio

    2017-05-01

    A range of information needs should be met in order to better understand and predict the longevity/existence of novel psychoactive substances (NPS). This conceptual paper argues that one way of assessing how long a molecule may be around is to document how the life cycles or natural histories of 'traditional' drugs and NPS evolve. The earliest indication of the possible appearance of a new substance might be evidenced on the DeepWeb. However, this means they are less visible, in line with the clandestine nature of drug use and supply. Therefore, monitoring discussion groups/fora needs the development of new methods compared to those used in the Surface Net. Issues needing consideration in establishing NPS life cycles are outlined here, together with the probable outcomes that could result. The approach advocated means that it should be easier to identify which NPS are likely to come up or are emerging in real time, and, therefore, pre-empt/prevent their supply. Copyright © 2017 John Wiley & Sons, Ltd.

  11. The influence of habitat fragmentation on helminth communities in rodent populations from a Brazilian Mountain Atlantic Forest.

    PubMed

    Cardoso, T S; Simões, R O; Luque, J L F; Maldonado, A; Gentile, R

    2016-07-01

    The influence of habitat structure on helminth communities of three sigomdontinae rodent species (Akodon cursor, A. montensis and Oligoryzomys nigripes) was investigated in forest fragments within an agricultural landscape in south-eastern Brazil. This is a pionner study correlating the occurrence of helminth species of rodent hosts with microhabitat characteristics. Rodents were collected from 12 fragments and in a continuous conserved area. Up to 13 nematode, three cestode and two trematode species were identified, and habitat fragmentation was found to have more influence on the helminth composition of O. nigripes compared to the other two rodent species. Fragmentation appeared to limit the development of some helminths' life cycles, e.g. with some species such as Trichofreitasia lenti, Protospirura numidica, Cysticercus fasciolaris and Avellaria sp., occurring mostly in areas with less anthropic impact. However, fragmentation did not seem to affect the life cycles of other dominant helminths, such as the trematode Canaania obesa, the nematodes Stilestrongylus lanfrediae, S. eta and S. aculeata, and the cestode Rodentolepis akodontis. The helminth community structure followed a nested pattern of distribution in A. montensis and O. nigripes. Stilestrongylus lanfrediae seemed to be more associated with dense understorey, C. obesa with open canopy and dense understorey, and Guerrerostrongylus zetta with organic matter on the ground. Their presence in each area may be explained by aspects of their life cycles that take place in the external environment outside the host.

  12. Independent divergence of 13- and 17-y life cycles among three periodical cicada lineages.

    PubMed

    Sota, Teiji; Yamamoto, Satoshi; Cooley, John R; Hill, Kathy B R; Simon, Chris; Yoshimura, Jin

    2013-04-23

    The evolution of 13- and 17-y periodical cicadas (Magicicada) is enigmatic because at any given location, up to three distinct species groups (Decim, Cassini, Decula) with synchronized life cycles are involved. Each species group is divided into one 13- and one 17-y species with the exception of the Decim group, which contains two 13-y species-13-y species are Magicicada tredecim, Magicicada neotredecim, Magicicada tredecassini, and Magicicada tredecula; and 17-y species are Magicicada septendecim, Magicicada cassini, and Magicicada septendecula. Here we show that the divergence leading to the present 13- and 17-y populations differs considerably among the species groups despite the fact that each group exhibits strikingly similar phylogeographic patterning. The earliest divergence of extant lineages occurred ∼4 Mya with one branch forming the Decim species group and the other subsequently splitting 2.5 Mya to form the Cassini and Decula species groups. The earliest split of extant lineages into 13- and 17-y life cycles occurred in the Decim lineage 0.5 Mya. All three species groups experienced at least one episode of life cycle divergence since the last glacial maximum. We hypothesize that despite independent origins, the three species groups achieved their current overlapping distributions because life-cycle synchronization of invading congeners to a dominant resident population enabled escape from predation and population persistence. The repeated life-cycle divergences supported by our data suggest the presence of a common genetic basis for the two life cycles in the three species groups.

  13. A new data architecture for advancing life cycle assessment

    EPA Science Inventory

    IntroductionLife cycle assessment (LCA) has a technical architecture that limits data interoperability, transparency, and automated integration of external data. More advanced information technologies offer promise for increasing the ease with which information can be synthesized...

  14. Host Life History Strategy, Species Diversity, and Habitat Influence Trypanosoma cruzi Vector Infection in Changing Landscapes

    PubMed Central

    Gottdenker, Nicole L.; Chaves, Luis Fernando; Calzada, José E.; Saldaña, Azael; Carroll, C. Ronald

    2012-01-01

    Background Anthropogenic land use may influence transmission of multi-host vector-borne pathogens by changing diversity, relative abundance, and community composition of reservoir hosts. These reservoir hosts may have varying competence for vector-borne pathogens depending on species-specific characteristics, such as life history strategy. The objective of this study is to evaluate how anthropogenic land use change influences blood meal species composition and the effects of changing blood meal species composition on the parasite infection rate of the Chagas disease vector Rhodnius pallescens in Panama. Methodology/Principal Findings R. pallescens vectors (N = 643) were collected in different habitat types across a gradient of anthropogenic disturbance. Blood meal species in DNA extracted from these vectors was identified in 243 (40.3%) vectors by amplification and sequencing of a vertebrate-specific fragment of the 12SrRNA gene, and T. cruzi vector infection was determined by pcr. Vector infection rate was significantly greater in deforested habitats as compared to contiguous forests. Forty-two different species of blood meal were identified in R. pallescens, and species composition of blood meals varied across habitat types. Mammals (88.3%) dominated R. pallescens blood meals. Xenarthrans (sloths and tamanduas) were the most frequently identified species in blood meals across all habitat types. A regression tree analysis indicated that blood meal species diversity, host life history strategy (measured as rmax, the maximum intrinsic rate of population increase), and habitat type (forest fragments and peridomiciliary sites) were important determinants of vector infection with T. cruzi. The mean intrinsic rate of increase and the skewness and variability of rmax were positively associated with higher vector infection rate at a site. Conclusions/Significance In this study, anthropogenic landscape disturbance increased vector infection with T. cruzi, potentially

  15. Comparison of algae cultivation methods for bioenergy production using a combined life cycle assessment and life cycle costing approach.

    PubMed

    Resurreccion, Eleazer P; Colosi, Lisa M; White, Mark A; Clarens, Andres F

    2012-12-01

    Algae are an attractive energy source, but important questions still exist about the sustainability of this technology on a large scale. Two particularly important questions concern the method of cultivation and the type of algae to be used. This present study combines elements of life cycle analysis (LCA) and life cycle costing (LCC) to evaluate open pond (OP) systems and horizontal tubular photobioreactors (PBRs) for the cultivation of freshwater (FW) or brackish-to-saline water (BSW) algae. Based on the LCA, OPs have lower energy consumption and greenhouse gas emissions than PBRs; e.g., 32% less energy use for construction and operation. According to the LCC, all four systems are currently financially unattractive investments, though OPs are less so than PBRs. BSW species deliver better energy and GHG performance and higher profitability than FW species in both OPs and PBRs. Sensitivity analyses suggest that improvements in critical cultivation parameters (e.g., CO(2) utilization efficiency or algae lipid content), conversion parameters (e.g., anaerobic digestion efficiency), and market factors (e.g., costs of CO(2) and electricity, or sale prices for algae biodiesel) could alter these results. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Terrestrial habitat selection and strong density-dependent mortality in recently metamorphosed amphibians.

    PubMed

    Patrick, David A; Harper, Elizabeth B; Hunter, Malcolm L; Calhoun, Aram J K

    2008-09-01

    To predict the effects of terrestrial habitat change on amphibian populations, we need to know how amphibians respond to habitat heterogeneity, and whether habitat choice remains consistent throughout the life-history cycle. We conducted four experiments to evaluate how the spatial distribution of juvenile wood frogs, Rana sylvatica (including both overall abundance and localized density), was influenced by habitat choice and habitat structure, and how this relationship changed with spatial scale and behavioral phase. The four experiments included (1) habitat manipulation on replicated 10-ha landscapes surrounding breeding pools; (2) short-term experiments with individual frogs emigrating through a manipulated landscape of 1 m wide hexagonal patches; and habitat manipulations in (3) small (4-m2); and (4) large (100-m2) enclosures with multiple individuals to compare behavior both during and following emigration. The spatial distribution of juvenile wood frogs following emigration resulted from differences in the scale at which juvenile amphibians responded to habitat heterogeneity during active vs. settled behavioral phases. During emigration, juvenile wood frogs responded to coarse-scale variation in habitat (selection between 2.2-ha forest treatments) but not to fine-scale variation. After settling, however, animals showed habitat selection at much smaller scales (2-4 m2). This resulted in high densities of animals in small patches of suitable habitat where they experienced rapid mortality. No evidence of density-dependent habitat selection was seen, with juveniles typically choosing to remain at extremely high densities in high-quality habitat, rather than occupying low-quality habitat. These experiments demonstrate how prediction of the terrestrial distribution of juvenile amphibians requires understanding of the complex behavioral responses to habitat heterogeneity. Understanding these patterns is important, given that human alterations to amphibian habitats

  17. Carbon footprint of forest and tree utilization technologies in life cycle approach

    NASA Astrophysics Data System (ADS)

    Polgár, András; Pécsinger, Judit

    2017-04-01

    In our research project a suitable method has been developed related the technological aspect of the environmental assessment of land use changes caused by climate change. We have prepared an eco-balance (environmental inventory) to the environmental effects classification in life-cycle approach in connection with the typical agricultural / forest and tree utilization technologies. The use of balances and environmental classification makes possible to compare land-use technologies and their environmental effects per common functional unit. In order to test our environmental analysis model, we carried out surveys in sample of forest stands. We set up an eco-balance of the working systems of intermediate cutting and final harvest in the stands of beech, oak, spruce, acacia, poplar and short rotation energy plantations (willow, poplar). We set up the life-cycle plan of the surveyed working systems by using the GaBi 6.0 Professional software and carried out midpoint and endpoint impact assessment. Out of the results, we applied the values of CML 2001 - Global Warming Potential (GWP 100 years) [kg CO2-Equiv.] and Eco-Indicator 99 - Human health, Climate Change [DALY]. On the basis of the values we set up a ranking of technology. By this, we received the environmental impact classification of the technologies based on carbon footprint. The working systems had the greatest impact on global warming (GWP 100 years) throughout their whole life cycle. This is explained by the amount of carbon dioxide releasing to the atmosphere resulting from the fuel of the technologies. Abiotic depletion (ADP foss) and marine aquatic ecotoxicity (MAETP) emerged also as significant impact categories. These impact categories can be explained by the share of input of fuel and lube. On the basis of the most significant environmental impact category (carbon footprint), we perform the relative life cycle contribution and ranking of each technologies. The technological life cycle stages examined

  18. Nomadic-colonial life strategies enable paradoxical survival and growth despite habitat destruction

    PubMed Central

    Tan, Zong Xuan; Cheong, Kang Hao

    2017-01-01

    Organisms often exhibit behavioral or phenotypic diversity to improve population fitness in the face of environmental variability. When each behavior or phenotype is individually maladaptive, alternating between these losing strategies can counter-intuitively result in population persistence–an outcome similar to the Parrondo’s paradox. Instead of the capital or history dependence that characterize traditional Parrondo games, most ecological models which exhibit such paradoxical behavior depend on the presence of exogenous environmental variation. Here we present a population model that exhibits Parrondo’s paradox through capital and history-dependent dynamics. Two sub-populations comprise our model: nomads, who live independently without competition or cooperation, and colonists, who engage in competition, cooperation, and long-term habitat destruction. Nomads and colonists may alternate behaviors in response to changes in the colonial habitat. Even when nomadism and colonialism individually lead to extinction, switching between these strategies at the appropriate moments can paradoxically enable both population persistence and long-term growth. DOI: http://dx.doi.org/10.7554/eLife.21673.001 PMID:28084993

  19. Parking infrastructure: energy, emissions, and automobile life-cycle environmental accounting

    NASA Astrophysics Data System (ADS)

    Chester, Mikhail; Horvath, Arpad; Madanat, Samer

    2010-07-01

    The US parking infrastructure is vast and little is known about its scale and environmental impacts. The few parking space inventories that exist are typically regionalized and no known environmental assessment has been performed to determine the energy and emissions from providing this infrastructure. A better understanding of the scale of US parking is necessary to properly value the total costs of automobile travel. Energy and emissions from constructing and maintaining the parking infrastructure should be considered when assessing the total human health and environmental impacts of vehicle travel. We develop five parking space inventory scenarios and from these estimate the range of infrastructure provided in the US to be between 105 million and 2 billion spaces. Using these estimates, a life-cycle environmental inventory is performed to capture the energy consumption and emissions of greenhouse gases, CO, SO2, NOX, VOC (volatile organic compounds), and PM10 (PM: particulate matter) from raw material extraction, transport, asphalt and concrete production, and placement (including direct, indirect, and supply chain processes) of space construction and maintenance. The environmental assessment is then evaluated within the life-cycle performance of sedans, SUVs (sports utility vehicles), and pickups. Depending on the scenario and vehicle type, the inclusion of parking within the overall life-cycle inventory increases energy consumption from 3.1 to 4.8 MJ by 0.1-0.3 MJ and greenhouse gas emissions from 230 to 380 g CO2e by 6-23 g CO2e per passenger kilometer traveled. Life-cycle automobile SO2 and PM10 emissions show some of the largest increases, by as much as 24% and 89% from the baseline inventory. The environmental consequences of providing the parking spaces are discussed as well as the uncertainty in allocating paved area between parking and roadways.

  20. Life cycle and economic efficiency analysis: durable pavement markings.

    DOT National Transportation Integrated Search

    2009-07-01

    This project examined the life cycle and economic efficiency of two pavement marking : materials inlaid tape and thermoplastic to find the most economical product for specific : traffic and weather conditions. Six locations in the state of Ma...

  1. Life cycle inventory energy consumption and emissions for biodiesel versus petroleum diesel fueled construction vehicles.

    PubMed

    Pang, Shih-Hao; Frey, H Christopher; Rasdorf, William J

    2009-08-15

    Substitution of soy-based biodiesel fuels for petroleum diesel will alter life cycle emissions for construction vehicles. A life cycle inventory was used to estimate fuel cycle energy consumption and emissions of selected pollutants and greenhouse gases. Real-world measurements using a portable emission measurement system (PEMS) were made forfive backhoes, four front-end loaders, and six motor graders on both fuels from which fuel consumption and tailpipe emission factors of CO, HC, NO(x), and PM were estimated. Life cycle fossil energy reductions are estimated it 9% for B20 and 42% for B100 versus petroleum diesel based on the current national energy mix. Fuel cycle emissions will contribute a larger share of total life cycle emissions as new engines enter the in-use fleet. The average differences in life cycle emissions for B20 versus diesel are: 3.5% higher for NO(x); 11.8% lower for PM, 1.6% higher for HC, and 4.1% lower for CO. Local urban tailpipe emissions are estimated to be 24% lower for HC, 20% lower for CO, 17% lower for PM, and 0.9% lower for NO(x). Thus, there are environmental trade-offs such as for rural vs urban areas. The key sources of uncertainty in the B20 LCI are vehicle emission factors.

  2. User’s Guide for Naval Material Command’s Life Cycle Cost (FLEX) Model.

    DTIC Science & Technology

    1982-04-01

    MATERIAL COMMANDl’S 3 LIFE CYCLE COST (FLEX) MODEL Icc FoIuhrInomto -- -- P ea eCo tc Pleale Cona, ______ _____-Thims document rc~ ofl 5C72 -lot REPORT...Material Command’s Life Cycle Cost (FLEX) Prep. 4/82 ___ Model ______________ ______________ 7. Author(s) S. Performing Organization Rapt. No. R. Dress (ESA...WANG 1I. Abstract (Limit: 200 words) The FLEX-9E life cycle cost comp~uter model is a user-oriented methodology accommodating most cost structures and

  3. The new reports on life cycle of Heterosigma akashiwo (Raphidophyceae)

    NASA Astrophysics Data System (ADS)

    Kim, J. H.

    2016-02-01

    Heterosigma akashiwo (Hada) Hada (Raphidophyceae) is a noxious bloom-forming algal species that has damaged many fish farms in coastal waters during recent decades. Consequently, many studies focused on the population dynamics of H. akashiwo, while its life cycle was not well studied. In this study, we investigated veiled life cycle of H. akashiwo through culture based method. We cultured eight H. akashiwostrains originated from Korea, Japan, USA under various conditions (water temp., light intensity, salinity, pH). Morphological diversity of cells were observed via light microscopy and scanning electron microscopy. To observe nucleus of living cell, cells were stained with Hoechst and changes of cells in culture were observed through time-lapse. For observation of cysts and their germination process, cysts were isolated from sediment. Different from the previous knowledge, H. akashiwo has only vegetative cell stage and cyst stage, we discovered that H. akashiwo has extra small cell stage and large cell stage. Large cells are much bigger (20-45 µm) than vegetative cells. Large cell formation was resulted from fusion of vegetative cells. Small cells were very small (6.88 ± 0.85 µm), these cell divided from large cell or formed in germination process of cysts rarely. Small cells have lower motility than vegetative cells. These results improved the study of life stages of H. akashiwo and this fundamental investigation provide important new information and improve our understanding of the life cycle of H. akashiwo.

  4. THE EMERGING FOCUS ON LIFE-CYCLE ASSESSMENT IN THE U. S. ENVIRONMENTAL PROTECTION AGENCY

    EPA Science Inventory

    EPA has been actively engaged in LCA research since 1990 to help advance the methodology and application of life cycle thinking in decision-making. Across the Agency consideration of the life cycle concept is increasing in the development of policies and programs. A major force i...

  5. Cycle life status of SAFT VOS nickel-cadmium cells

    NASA Technical Reports Server (NTRS)

    Goualard, Jacques

    1993-01-01

    The SAFT prismatic VOS Ni-Cd cells have been flown in geosynchronous orbit since 1977 and in low earth orbit since 1983. Parallel cycling tests are performed by several space agencies in order to determine the cycle life for a wide range of temperature and depth of discharge (DOD). In low Earth orbit (LEO), the ELAN program is conducted on 24 Ah cells by CNES and ESA at the European Battery Test Center at temperatures ranging from 0 to 27 C and DOD from 10 to 40 percent. Data are presented up to 37,000 cycles. One pack (X-80) has achieved 49,000 cycles at 10 C and 23 percent DOD. The geosynchronous orbit simulation of a high DOD test is conducted by ESA on 3 batteries at 10 C and 70, 90, and 100 percent DOD. Thirty-one eclipse seasons are completed, and no signs of degradation have been found. The Air Force test at CRANE on 24 Ah and 40 Ah cells at 20 C and 80 percent DOD has achieved 19 shadow periods. Life expectancy is discussed. The VOS cell technology could be used for the following: (1) in geosynchronous conditions--15 yrs at 10-15 C and 80 percent DOD; and (2) in low earth orbit--10 yrs at 5-15 C and 25-30 percent DOD.

  6. Educational inequalities in smoking over the life cycle: an analysis by cohort and gender.

    PubMed

    Bricard, Damien; Jusot, Florence; Beck, François; Khlat, Myriam; Legleye, Stéphane

    2016-01-01

    The study investigates the life cycle patterns of educational inequalities in smoking according to gender over three successive generations. Based on retrospective smoking histories collected by the nationwide French Health Barometer survey 2010, we explored educational inequalities in smoking at each age, using the relative index of inequality. Educational inequalities in smoking increase across cohorts for men and women, corresponding to a decline in smoking among the highly educated alongside progression among the lower educated. The analysis also shows a life cycle evolution: for all cohorts and for men and women, inequalities are considerable during adolescence, then start declining from 18 years until the age of peak prevalence (around 25), after which they remain stable throughout the life cycle, even tending to rise for the most recent cohort. This analysis contributes to the description of the "smoking epidemic" and highlights adolescence and late adulthood as life cycle stages with greater inequalities.

  7. The Life Cycle of Stratospheric Aerosol Particles

    NASA Technical Reports Server (NTRS)

    Hamill, Patrick; Jensen, Eric J.; Russell, P. B.; Bauman, Jill J.

    1997-01-01

    This paper describes the life cycle of the background (nonvolcanic) stratospheric sulfate aerosol. The authors assume the particles are formed by homogeneous nucleation near the tropical tropopause and are carried aloft into the stratosphere. The particles remain in the Tropics for most of their life, and during this period of time a size distribution is developed by a combination of coagulation, growth by heteromolecular condensation, and mixing with air parcels containing preexisting sulfate particles. The aerosol eventually migrates to higher latitudes and descends across isentropic surfaces to the lower stratosphere. The aerosol is removed from the stratosphere primarily at mid- and high latitudes through various processes, mainly by isentropic transport across the tropopause from the stratosphere into the troposphere.

  8. A comparative study of commercial lithium ion battery cycle life in electric vehicle: Capacity loss estimation

    NASA Astrophysics Data System (ADS)

    Han, Xuebing; Ouyang, Minggao; Lu, Languang; Li, Jianqiu

    2014-12-01

    Now the lithium ion batteries are widely used in electric vehicles (EV). The cycle life is among the most important characteristics of the power battery in EV. In this report, the battery cycle life experiment is designed according to the actual working condition in EV. Five different commercial lithium ion cells are cycled alternatively under 45 °C and 5 °C and the test results are compared. Based on the cycle life experiment results and the identified battery aging mechanism, the battery cycle life models are built and fitted by the genetic algorithm. The capacity loss follows a power law relation with the cycle times and an Arrhenius law relation with the temperature. For automotive application, to save the cost and the testing time, a battery SOH (state of health) estimation method combined the on-line model based capacity estimation and regular calibration is proposed.

  9. Habitats for life in the Venusian Environment? Can the VENUS EXPRESS payload answer?

    NASA Astrophysics Data System (ADS)

    Muller, C.

    2003-04-01

    The Venusian conditions are unique in the solar system. Venus abounds in molecules which could feed a life form except that the usual missing factor, energy, is present in excessive amounts from both active geothermic phenomena and from the nearby solar radiation trapped in a dense carbon dioxide atmosphere. Its surface conditions are hotter than the best practiced in hospital sterilisation; volcanism injects highly toxic gases which in the absence of water can accumulate in the atmosphere. Its upper atmosphere lays bare to solar radiation with only carbon dioxide to act as a confirmed EUV filter, so any consideration of life might seem excessive compared to what was known from life on earth before extremophile bacterias were discovered in dark undersea high temperature sulphur rich volcanic vents. However, some regions of the atmosphere might show conditions similar to the earth surface and could be a habitat of earth like microbial life. A synergy between the different atmospheric instruments of the VENUS-Express payload: SPICAM, VIRTIS and PFS can provide the way to probe the actual environmental conditions of this region and to check its capabilities of preserving an extant life or providing nutrients to a new one.

  10. Meta-analysis and Harmonization of Life Cycle Assessment Studies for Algae Biofuels.

    PubMed

    Tu, Qingshi; Eckelman, Matthew; Zimmerman, Julie

    2017-09-05

    Algae biodiesel (BioD) and renewable diesel (RD) have been recognized as potential solutions to mitigating fossil-fuel consumption and the associated environmental issues. Life cycle assessment (LCA) has been used by many researchers to evaluate the potential environmental impacts of these algae-derived fuels, yielding a wide range of results and, in some cases, even differing on indicating whether these fuels are preferred to petroleum-derived fuels or not. This meta-analysis reviews the methodological preferences and results for energy consumption, greenhouse gas emissions, and water consumption for 54 LCA studies that considered algae BioD and RD. The significant variation in reported results can be primarily attributed to the difference in scope, assumptions, and data sources. To minimize the variation in life cycle inventory calculations, a harmonized inventory data set including both nominal and uncertainty data is calculated for each stage of the algae-derived fuel life cycle.

  11. The caligid life cycle: new evidence from Lepeophtheirus elegans reconciles the cycles of Caligus and Lepeophtheirus (Copepoda: Caligidae)

    PubMed Central

    Venmathi Maran, Balu Alagar; Moon, Seong Yong; Ohtsuka, Susumu; Oh, Sung-Yong; Soh, Ho Young; Myoung, Jung-Goo; Iglikowska, Anna; Boxshall, Geoffrey Allan

    2013-01-01

    The developmental stages of the sea louse Lepeophtheirus elegans (Copepoda: Caligidae) are described from material collected from marine ranched Korean rockfish, Sebastes schlegelii. In L. elegans, setal number on the proximal segment of the antennule increases from 3 in the copepodid to 27 in the adult. Using the number of setae as a stage marker supports the inference that the post-naupliar phase of the life cycle comprises six stages: copepodid, chalimus I, chalimus II, pre-adult I, pre-adult II, and the adult. We observed variation in body length in both of the chalimus stages which we consider represents an early expression of sexual size dimorphism. We interpret the larger specimens of chalimus I as putative females, and the smaller as putative males; similarly with chalimus II, larger specimens are putative females and the smaller are males. Two patterns of life cycle are currently recognized within the Caligidae but the evidence presented here reconciles the two. We conclude that the typical caligid life cycle comprises only eight stages: two naupliar, one copepodid, and four chalimus stages preceding the adult in Caligus, but with the four chalimus stages represented by two chalimus and two pre-adult stages in Lepeophtheirus. This is a profound change with significant implications for the aquaculture industry, given that lice monitoring protocols include counts of chalimus stages and use temperature to predict when they will moult into the more pathogenic, mobile pre-adults. Lice management strategies must be tailored to the precise life cycle of the parasite. PMID:23647664

  12. A Watershed Scale Life Cycle Assessment Framework for Hydrologic Design

    NASA Astrophysics Data System (ADS)

    Tavakol-Davani, H.; Tavakol-Davani, PhD, H.; Burian, S. J.

    2017-12-01

    Sustainable hydrologic design has received attention from researchers with different backgrounds, including hydrologists and sustainability experts, recently. On one hand, hydrologists have been analyzing ways to achieve hydrologic goals through implementation of recent environmentally-friendly approaches, e.g. Green Infrastructure (GI) - without quantifying the life cycle environmental impacts of the infrastructure through the ISO Life Cycle Assessment (LCA) method. On the other hand, sustainability experts have been applying the LCA to study the life cycle impacts of water infrastructure - without considering the important hydrologic aspects through hydrologic and hydraulic (H&H) analysis. In fact, defining proper system elements for a watershed scale urban water sustainability study requires both H&H and LCA specialties, which reveals the necessity of performing an integrated, interdisciplinary study. Therefore, the present study developed a watershed scale coupled H&H-LCA framework to bring the hydrology and sustainability expertise together to contribute moving the current wage definition of sustainable hydrologic design towards onto a globally standard concept. The proposed framework was employed to study GIs for an urban watershed in Toledo, OH. Lastly, uncertainties associated with the proposed method and parameters were analyzed through a robust Monte Carlo simulation using parallel processing. Results indicated the necessity of both hydrologic and LCA components in the design procedure in order to achieve sustainability.

  13. Life cycle assessment of the application of nanoclays in wire coating

    NASA Astrophysics Data System (ADS)

    Tellaetxe, A.; Blázquez, M.; Arteche, A.; Egizabal, A.; Ermini, V.; Rose, J.; Chaurand, P.; Unzueta, I.

    2012-09-01

    A life cycle assessment (LCA) is carried out to compare nanoclay-reinforced polymer wire coatings with conventional ones. While the conventional wire coatings contain standard halogen free retardants, in reinforced coatings, montmorillonite (nanoclay) is incorporated into electric cable linings as a rheological agent for an increased resistance to fire. In addition, a reduced load of standard halogen free retardants is obtained. The synergistic effect of the montmorillonite on traditional flame retardant additives (by the formation of a three-dimensional char network) can lead to a revolution in wire production. The application of nanoclays contributes also to anti-dripping effect and flexibility increase [1]. Some producers have already started commercializing wire with nanotechnology-based coating; in the short term the use of nanoclay in wire coating production will probably reach a significant market share replacing traditional formulations. The main aim of this study is to compare the environmental impacts along the life cycle of a traditional wire coating (mineral flame retardants like ATH or MDH in a polymer matrix) with the nanoclay-reinforced wire coating, where the montmorillonite replaces a low percentage of the mineral flame retardant. The system boundaries of the study include the following unit processes: nanoclay production, thermoplastic material and mineral flame retardants production, cable coating manufacturing by extrusion and different end of life scenarios (recycling, incineration and landfill disposal). Whereas nanoreinforced composites have shown and increased fire retardance, the addition of nanomaterials seems to have no significant relevance in the environmental assessment. However, the lack of nano-specific characterization factors for nanomaterials and emission rates associated to the different life cycle stages -mainly in the extrusion and use phase, where accidental combustions can take place- still remains a challenge for realistic

  14. 10 CFR 455.64 - Life-cycle cost methodology.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-investment ratio is the ratio of the present value of net cost savings attributable to an energy conservation measure to the present value of the net increase in investment, maintenance and operating, and replacement... present value. The format for displaying life-cycle costs shall be a savings-to-investment ratio. (b) An...

  15. 10 CFR 455.64 - Life-cycle cost methodology.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...-investment ratio is the ratio of the present value of net cost savings attributable to an energy conservation measure to the present value of the net increase in investment, maintenance and operating, and replacement... present value. The format for displaying life-cycle costs shall be a savings-to-investment ratio. (b) An...

  16. 10 CFR 455.64 - Life-cycle cost methodology.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-investment ratio is the ratio of the present value of net cost savings attributable to an energy conservation measure to the present value of the net increase in investment, maintenance and operating, and replacement... present value. The format for displaying life-cycle costs shall be a savings-to-investment ratio. (b) An...

  17. Effect of KOH concentration on LEO cycle life of IPV nickel-hydrogen flight cell - Update II

    NASA Technical Reports Server (NTRS)

    Smithrick, John J.; Hall, Stephen W.

    1992-01-01

    An update of validation test results confirming the breakthrough in LEO cycle life of nickel-hydrogen cells containing 26 percent KOH electrolyte is presented. A breakthrough in the LEO cycle life of individual pressure vessel (IPV) nickel-hydrogen cells has been previously reported. The cycle life of boiler plate cells containing 26 percent potassium hydroxide (KOH) electrolyte was about 40,000 LEO cycles, compared to 3500 cycles for cells containing 31 percent KOH. The cycle regime was a stressful accelerated LEO, which consisted of a 27.5 min charge followed by a 17.5 min discharge (2X normal rate). The depth-of-discharge was 80 percent. Six 48-Ah Hughes recirculation design IPV nickel-hydrogen flight battery cells are being evaluated. Three of the cells contain 26 percent KOH (test cells), and three contain 31 percent KOH (control cells). They are undergoing real time LEO cycle life testing. The cycle regime is a 90-min LEO orbit consisting of a 54-min charge followed by a 36-min discharge. The depth-of-discharge is 80 percent. The cell temperature is maintained at 10 C. The three 31 percent KOH cells failed (cycles 3729, 4165, and 11355). One of the 26 percent KOH cells failed at cycle 15314. The other two 26 percent KOH cells were cycled for over 16,000 cycles during the continuing test.

  18. Life cycle models of conventional and alternative-fueled automobiles

    NASA Astrophysics Data System (ADS)

    Maclean, Heather Louise

    This thesis reports life cycle inventories of internal combustion engine automobiles with feasible near term fuel/engine combinations. These combinations include unleaded gasoline, California Phase 2 Reformulated Gasoline, alcohol and gasoline blends (85 percent methanol or ethanol combined with 15 percent gasoline), and compressed natural gas in spark ignition direct and indirect injection engines. Additionally, I consider neat methanol and neat ethanol in spark ignition direct injection engines and diesel fuel in compression ignition direct and indirect injection engines. I investigate the potential of the above options to have a lower environmental impact than conventional gasoline-fueled automobiles, while still retaining comparable pricing and consumer benefits. More broadly, the objective is to assess whether the use of any of the alternative systems will help to lead to the goal of a more sustainable personal transportation system. The principal tool is the Economic Input-Output Life Cycle Analysis model which includes inventories of economic data, environmental discharges, and resource use. I develop a life cycle assessment framework to assemble the array of data generated by the model into three aggregate assessment parameters; economics, externalities, and vehicle attributes. The first step is to develop a set of 'comparable cars' with the alternative fuel/engine combinations, based on characteristics of a conventional 1998 gasoline-fueled Ford Taurus sedan, the baseline vehicle for the analyses. I calculate the assessment parameters assuming that these comparable cars can attain the potential thermal efficiencies estimated by experts for each fuel/engine combination. To a first approximation, there are no significant differences in the assessment parameters for the vehicle manufacture, service, fixed costs, and the end-of-life for any of the options. However, there are differences in the vehicle operation life cycle components and the state of technology

  19. Life Cycle Costing: A Working Level Approach

    DTIC Science & Technology

    1981-06-01

    Effects Analysis ( FMEA ) ...... ................ .. 59 Logistics Performance Factors (LPFs) 60 Planning the Use of Life Cycle Cost in the Demonstration...form. Failure Mode and Effects Analysis ( FMEA ). Description. FMEA is a technique that attempts to improve the design of any particular unit. The FMEA ...failure modes and also eliminate extra parts or ones that are used to achieve more performance than is necessary (16:5-14]. Advantages. FMEA forces

  20. Guidance on How to Move from Current Practice to Recommended Practice in Life Cycle Impact Assessment (UNEP/SETAC Life Cycle Initiative Publication)

    EPA Science Inventory

    The report provides guidance on how to move from current practice to recommended practice in Life Cycle Impact Assessment. It is composed of three complementary parts elaborated in the first task force (TFI) of the LCIA programme, with contribution of the other three task forces:

  1. Analysis of the Seismic Performance of Isolated Buildings according to Life-Cycle Cost

    PubMed Central

    Dang, Yu; Han, Jian-ping; Li, Yong-tao

    2015-01-01

    This paper proposes an indicator of seismic performance based on life-cycle cost of a building. It is expressed as a ratio of lifetime damage loss to life-cycle cost and determines the seismic performance of isolated buildings. Major factors are considered, including uncertainty in hazard demand and structural capacity, initial costs, and expected loss during earthquakes. Thus, a high indicator value indicates poor building seismic performance. Moreover, random vibration analysis is conducted to measure structural reliability and evaluate the expected loss and life-cycle cost of isolated buildings. The expected loss of an actual, seven-story isolated hospital building is only 37% of that of a fixed-base building. Furthermore, the indicator of the structural seismic performance of the isolated building is much lower in value than that of the structural seismic performance of the fixed-base building. Therefore, isolated buildings are safer and less risky than fixed-base buildings. The indicator based on life-cycle cost assists owners and engineers in making investment decisions in consideration of structural design, construction, and expected loss. It also helps optimize the balance between building reliability and building investment. PMID:25653677

  2. Analysis of the seismic performance of isolated buildings according to life-cycle cost.

    PubMed

    Dang, Yu; Han, Jian-Ping; Li, Yong-Tao

    2015-01-01

    This paper proposes an indicator of seismic performance based on life-cycle cost of a building. It is expressed as a ratio of lifetime damage loss to life-cycle cost and determines the seismic performance of isolated buildings. Major factors are considered, including uncertainty in hazard demand and structural capacity, initial costs, and expected loss during earthquakes. Thus, a high indicator value indicates poor building seismic performance. Moreover, random vibration analysis is conducted to measure structural reliability and evaluate the expected loss and life-cycle cost of isolated buildings. The expected loss of an actual, seven-story isolated hospital building is only 37% of that of a fixed-base building. Furthermore, the indicator of the structural seismic performance of the isolated building is much lower in value than that of the structural seismic performance of the fixed-base building. Therefore, isolated buildings are safer and less risky than fixed-base buildings. The indicator based on life-cycle cost assists owners and engineers in making investment decisions in consideration of structural design, construction, and expected loss. It also helps optimize the balance between building reliability and building investment.

  3. Life Cycle Water Consumption and Wastewater Generation Impacts of a Marcellus Shale Gas Well

    PubMed Central

    2013-01-01

    This study estimates the life cycle water consumption and wastewater generation impacts of a Marcellus shale gas well from its construction to end of life. Direct water consumption at the well site was assessed by analysis of data from approximately 500 individual well completion reports collected in 2010 by the Pennsylvania Department of Conservation and Natural Resources. Indirect water consumption for supply chain production at each life cycle stage of the well was estimated using the economic input–output life cycle assessment (EIO-LCA) method. Life cycle direct and indirect water quality pollution impacts were assessed and compared using the tool for the reduction and assessment of chemical and other environmental impacts (TRACI). Wastewater treatment cost was proposed as an additional indicator for water quality pollution impacts from shale gas well wastewater. Four water management scenarios for Marcellus shale well wastewater were assessed: current conditions in Pennsylvania; complete discharge; direct reuse and desalination; and complete desalination. The results show that under the current conditions, an average Marcellus shale gas well consumes 20 000 m3 (with a range from 6700 to 33 000 m3) of freshwater per well over its life cycle excluding final gas utilization, with 65% direct water consumption at the well site and 35% indirect water consumption across the supply chain production. If all flowback and produced water is released into the environment without treatment, direct wastewater from a Marcellus shale gas well is estimated to have 300–3000 kg N-eq eutrophication potential, 900–23 000 kg 2,4D-eq freshwater ecotoxicity potential, 0–370 kg benzene-eq carcinogenic potential, and 2800–71 000 MT toluene-eq noncarcinogenic potential. The potential toxicity of the chemicals in the wastewater from the well site exceeds those associated with supply chain production, except for carcinogenic effects. If all the Marcellus shale well

  4. Life cycle water consumption and wastewater generation impacts of a Marcellus shale gas well.

    PubMed

    Jiang, Mohan; Hendrickson, Chris T; VanBriesen, Jeanne M

    2014-01-01

    This study estimates the life cycle water consumption and wastewater generation impacts of a Marcellus shale gas well from its construction to end of life. Direct water consumption at the well site was assessed by analysis of data from approximately 500 individual well completion reports collected in 2010 by the Pennsylvania Department of Conservation and Natural Resources. Indirect water consumption for supply chain production at each life cycle stage of the well was estimated using the economic input-output life cycle assessment (EIO-LCA) method. Life cycle direct and indirect water quality pollution impacts were assessed and compared using the tool for the reduction and assessment of chemical and other environmental impacts (TRACI). Wastewater treatment cost was proposed as an additional indicator for water quality pollution impacts from shale gas well wastewater. Four water management scenarios for Marcellus shale well wastewater were assessed: current conditions in Pennsylvania; complete discharge; direct reuse and desalination; and complete desalination. The results show that under the current conditions, an average Marcellus shale gas well consumes 20,000 m(3) (with a range from 6700 to 33,000 m(3)) of freshwater per well over its life cycle excluding final gas utilization, with 65% direct water consumption at the well site and 35% indirect water consumption across the supply chain production. If all flowback and produced water is released into the environment without treatment, direct wastewater from a Marcellus shale gas well is estimated to have 300-3000 kg N-eq eutrophication potential, 900-23,000 kg 2,4D-eq freshwater ecotoxicity potential, 0-370 kg benzene-eq carcinogenic potential, and 2800-71,000 MT toluene-eq noncarcinogenic potential. The potential toxicity of the chemicals in the wastewater from the well site exceeds those associated with supply chain production, except for carcinogenic effects. If all the Marcellus shale well wastewater is

  5. Effect of positive pulse charge waveforms on cycle life of nickel-zinc cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.

    1980-01-01

    Five amp-hour nickel-zinc cells were life cycled to evaluate four different charge methods. Three of the four waveforms investigated were 120 Hz full wave rectified sinusoidal (FWRS), 120 Hz silicon controlled rectified (SCR), and 1 kHz square wave (SW). The fourth, a constant current method, was used as a baseline of comparison. Three sealed Ni-Zn cells connected in series were cycled. Each series string was charged at an average c/20 rate, and discharged at a c/2.5 rate to a 75% rated depth. Results indicate that the relatively inexpensive 120 Hz FWRS charger appears feasible for charging 5 amp-hour nickel-zinc cells with no significant loss in average cycle life when compared to constant current charging. The 1-kHz SW charger could also be used with no significant loss in average cycle life, and suggests the possibility of utilizing the existing electric vehicle chopper controller circuitry for an on-board charger. There was an apparent difference using the 120 Hz SCR charger compared to the others, however, this difference could be due to an inadvertent severe overcharge, which occurred prior to cell failure. The remaining two positive pulse charging waveforms, FWRS and 1 kHz, did not improve the cycle life of 5 amp-hour nickel-zinc cells over that of constant current charging.

  6. AN INTERNATIONAL WORKSHOP ON LIFE CYCLE IMPACT ASSESSMENT SOPHISTICATION

    EPA Science Inventory

    On November 29-30,1998 in Brussels, an international workshop was held to discuss Life Cycle Impact Assessment (LCIA) Sophistication. Approximately 50 LCA experts attended the workshop from North America, Europe, and Asia. Prominant practicioners and researchers were invited to ...

  7. ANALYZING SHORT CUT METHODS FOR LIFE CYCLE ASSESSMENT INVENTORIES

    EPA Science Inventory

    Work in progress at the U.S. EPA's National Risk Management Research Laboratory is developing methods for quickly, easily, and inexpensively developing Life Cycle Assessment (LCA) inventories. An LCA inventory represents the inputs and outputs from processes, including fuel and ...

  8. Temporal segmentation of animal trajectories informed by habitat use

    USGS Publications Warehouse

    van Toor, Marielle L.; Newman, Scott H.; Takekawa, John Y.; Wegmann, Martin; Safi, Kamran

    2016-01-01

    Most animals live in seasonal environments and experience very different conditions throughout the year. Behavioral strategies like migration, hibernation, and a life cycle adapted to the local seasonality help to cope with fluctuations in environmental conditions. Thus, how an individual utilizes the environment depends both on the current availability of habitat and the behavioral prerequisites of the individual at that time. While the increasing availability and richness of animal movement data has facilitated the development of algorithms that classify behavior by movement geometry, changes in the environmental correlates of animal movement have so far not been exploited for a behavioral annotation. Here, we suggest a method that uses these changes in individual–environment associations to divide animal location data into segments of higher ecological coherence, which we term niche segmentation. We use time series of random forest models to evaluate the transferability of habitat use over time to cluster observational data accordingly. We show that our method is able to identify relevant changes in habitat use corresponding to both changes in the availability of habitat and how it was used using simulated data, and apply our method to a tracking data set of common teal (Anas crecca). The niche segmentation proved to be robust, and segmented habitat suitability outperformed models neglecting the temporal dynamics of habitat use. Overall, we show that it is possible to classify animal trajectories based on changes of habitat use similar to geometric segmentation algorithms. We conclude that such an environmentally informed classification of animal trajectories can provide new insights into an individuals' behavior and enables us to make sensible predictions of how suitable areas might be connected by movement in space and time.

  9. Induction of Phase Variation Events in the Life Cycle of the Marine Coccolithophorid Emiliania huxleyi

    PubMed Central

    Laguna, Richard; Romo, Jesus; Read, Betsy A.; Wahlund, Thomas M.

    2001-01-01

    Emiliania huxleyi is a unicellular marine alga that is considered to be the world's major producer of calcite. The life cycle of this alga is complex and is distinguished by its ability to synthesize exquisitely sculptured calcium carbonate cell coverings known as coccoliths. These structures have been targeted by materials scientists for applications relating to the chemistry of biomedical materials, robust membranes for high-temperature separation technology, lightweight ceramics, and semiconductor design. To date, however, the molecular and biochemical events controlling coccolith production have not been determined. In addition, little is known about the life cycle of E. huxleyi and the environmental and physiological signals triggering phase switching between the diploid and haploid life cycle stages. We have developed laboratory methods for inducing phase variation between the haploid (S-cell) and diploid (C-cell) life cycle stages of E. huxleyi. Plating E. huxleyi C cells on solid media was shown to induce phase switching from the C-cell to the S-cell life cycle stage, the latter of which has been maintained for over 2 years under these conditions. Pure cultures of S cells were obtained for the first time. Laboratory conditions for inducing phase switching from the haploid stage to the diploid stage were also established. Regeneration of the C-cell stage from pure cultures of S cells followed a predictable pattern involving formation of large aggregations of S cells and the subsequent production of cultures consisting predominantly of diploid C cells. These results demonstrate the ability to manipulate the life cycle of E. huxleyi under controlled laboratory conditions, providing us with powerful tools for the development of genetic techniques for analysis of coccolithogenesis and for investigating the complex life cycle of this important marine alga. PMID:11525973

  10. Delayed-onset PTSD among war veterans: the role of life events throughout the life cycle.

    PubMed

    Horesh, Danny; Solomon, Z; Zerach, G; Ein-Dor, T

    2011-09-01

    The underlying mechanisms of delayed-onset PTSD are yet to be understood. This study examines the role of stressful life events throughout the life cycle in delayed-onset PTSD following combat. 675 Israeli veterans from the 1982 Lebanon War, 369 with antecedent combat stress reaction (CSR) and 306 without CSR were assessed prospectively, 1, 2 and 20 years after the war. Veterans were divided into four groups, according to the time of first PTSD onset (first onset at 1983, 1984, and 2002 and no PTSD onset). They were assessed for post-, peri- and pre-traumatic life events, as well as military and socio-demographic characteristics. Our findings indicate that shorter delays in PTSD onset were associated with a higher risk for CSR, a higher number of pre- and post-war life events, more severe subjective battle exposure, greater perceived danger during combat and a more stressful military position. CSR was found to be the most powerful predictor of PTSD onset. A recency effect was also found, with more recent life events proving to be stronger predictors of PTSD onset. First, our findings validate the existence of delayed-onset PTSD, as it was found among a substantial number of participants (16.5%). Second, post-, peri- and pre-traumatic life events are associated with the time of PTSD onset. Thus, practitioners and researchers are encouraged to examine not only the original trauma, but also the stressful experiences throughout the survivors' life cycle. In particular, identification of antecedent CSR may help mental help professionals in targeting high-risk populations.

  11. An accelerated calendar and cycle life study of Li-ion cells.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bloom, I.; Cole, B. W.; Sohn, J. J.

    2001-10-15

    The accelerated calendar and cycle life of lithium-ion cells was studied. Useful cell life was strongly affected by temperature, time, state-of-charge (SOC) and change in state-of-charge ({Delta}SOC). In calendar life experiments, useful cell life was strongly affected by temperature and time. Temperature accelerated cell performance degradation. The rates of area specific impedance (ASI) increase and power fade followed simple laws based on a power of time and Arrhenius kinetics. The data have been modeled using these two concepts and the calculated data agree well with the experimental values. The calendar life ASI increase and power fade data follow (time){sup 1/2}more » kinetics. This behavior may be due to solid electrolyte interface layer growth. From the cycle life experiments, the ASI increase data follow (time){sup 1/2} kinetics also, but there is an apparent change in overall power fade mechanism when going from 3 to 6% {Delta}SOC. Here, the power of time drops to below 1/2, which indicates that the power fade mechanism is more complex than layer growth.« less

  12. Using project life-cycles as guide for timing the archival of scientific data and supporting documentation

    NASA Astrophysics Data System (ADS)

    Martinez, E.; Glassy, J. M.; Fowler, D. K.; Khayat, M.; Olding, S. W.

    2014-12-01

    The NASA Earth Science Data Systems Working Groups (ESDSWG) focuses on improving technologies and processes related to science discovery and preservation. One particular group, the Data Preservation Practices, is defining a set of guidelines to aid data providers in planning both what to submit for archival, and when to submit artifacts, so that the archival process can begin early in the project's life cycle. This has the benefit of leveraging knowledge within the project before staff roll off to other work. In this poster we describe various project archival use cases and identify possible archival life cycles that map closely to the pace and flow of work. To understand "archival life cycles", i.e., distinct project phases that produce archival artifacts such as instrument capabilities, calibration reports, and science data products, the workig group initially mapped the archival requirements defined in the Preservation Content Specification to the typical NASA project life cycle. As described in the poster, this work resulted in a well-defined archival life cycle, but only for some types of projects; it did not fit well for condensed project life cycles experienced within airborne and balloon campaigns. To understand the archival process for projects with compressed cycles, the working group gathered use cases from various communities. This poster will describe selected uses cases that provided insight into the unique flow of these projects, as well as proposing archival life cycles that map artifacts to projects with compressed timelines. Finally, the poster will conclude with some early recommendations for data providers, which will be captured in a formal Guidelines document - to be published in 2015.

  13. Life-Cycle Inventory Analysis of Manufacturing Redwood Decking

    Treesearch

    Richard D. Bergman; Han-Sup Han; Elaine Oneil; Ivan L. Eastin

    2012-01-01

    Green building has become increasingly important. Therefore, consumers and builders often take into account the environmental attributes of a building material. This study determined the environmental attributes associated with manufacturing 38-mm × 138-mm (nominal 2 × 6) redwood decking in northern California using the life-cycle inventory method. Primary data...

  14. The role of interest and inflation rates in life-cycle cost analysis

    NASA Technical Reports Server (NTRS)

    Eisenberger, I.; Remer, D. S.; Lorden, G.

    1978-01-01

    The effect of projected interest and inflation rates on life cycle cost calculations is discussed and a method is proposed for making such calculations which replaces these rates by a single parameter. Besides simplifying the analysis, the method clarifies the roles of these rates. An analysis of historical interest and inflation rates from 1950 to 1976 shows that the proposed method can be expected to yield very good projections of life cycle cost even if the rates themselves fluctuate considerably.

  15. Evolution of haploid-diploid life cycles when haploid and diploid fitnesses are not equal.

    PubMed

    Scott, Michael F; Rescan, Marie

    2017-02-01

    Many organisms spend a significant portion of their life cycle as haploids and as diploids (a haploid-diploid life cycle). However, the evolutionary processes that could maintain this sort of life cycle are unclear. Most previous models of ploidy evolution have assumed that the fitness effects of new mutations are equal in haploids and homozygous diploids, however, this equivalency is not supported by empirical data. With different mutational effects, the overall (intrinsic) fitness of a haploid would not be equal to that of a diploid after a series of substitution events. Intrinsic fitness differences between haploids and diploids can also arise directly, for example because diploids tend to have larger cell sizes than haploids. Here, we incorporate intrinsic fitness differences into genetic models for the evolution of time spent in the haploid versus diploid phases, in which ploidy affects whether new mutations are masked. Life-cycle evolution can be affected by intrinsic fitness differences between phases, the masking of mutations, or a combination of both. We find parameter ranges where these two selective forces act and show that the balance between them can favor convergence on a haploid-diploid life cycle, which is not observed in the absence of intrinsic fitness differences. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  16. Understanding Existing Salmonid Habitat Availability and Connectivity to Improve River Management

    NASA Astrophysics Data System (ADS)

    Duffin, J.; Yager, E.; Tonina, D.; Benjankar, R. M.

    2017-12-01

    In the Pacific Northwest river restoration is common for salmon conservation. Mangers need methods to help target restoration to problem areas in rivers to create habitat that meets a species' needs. Hydraulic models and habitat suitability curves provide basic information on habitat availability and overall quality, but these analyses need to be expanded to address habitat quality based on the accessibility of habitats required for multiple life stages. Scientists are starting to use connectivity measurements to understand the longitudinal proximity of habitat patches, which can be used to address the habitat variability of a reach. By evaluating the availability and quality of habitat and calculating the connectivity between complementary habitats, such as spawning and rearing habitats, we aim to identify areas that should be targeted for restoration. To meet these goals, we assessed Chinook salmon habitat on the Lemhi River in Idaho. The depth and velocity outputs from a 2D hydraulic model are used in conjunction with locally created habitat suitability curves to evaluate the availability and quality of habitat for multiple Chinook salmon life stages. To assess the variability of the habitat, connectivity between habitat patches necessary for different life stages is calculated with a proximity index. A spatial representation of existing habitat quality and connectivity between complimentary habitats can be linked to river morphology by the evaluation of local geomorphic characteristics, including sinuosity and channel units. The understanding of the current habitat availability for multiple life stage needs, the connectivity between these habitat patches, and their relationship with channel morphology can help managers better identify restoration needs and direct their limited resources.

  17. Time is money: Rational life cycle inertia and the delegation of investment management.

    PubMed

    Kim, Hugh Hoikwang; Maurer, Raimond; Mitchell, Olivia S

    2016-08-01

    Many households display inertia in investment management over their life cycles. Our calibrated dynamic life cycle portfolio choice model can account for such an apparently 'irrational' outcome, by incorporating the fact that investors must forgo acquiring job-specific skills when they spend time managing their money, and their efficiency in financial decision making varies with age. Resulting inertia patterns mesh well with findings from prior studies and our own empirical results from Panel Study of Income Dynamics (PSID) data. We also analyze how people optimally choose between actively managing their assets versus delegating the task to financial advisors. Delegation proves valuable to both the young and the old. Our calibrated model quantifies welfare gains from including investment time and money costs as well as delegation in a life cycle setting.

  18. Time is money: Rational life cycle inertia and the delegation of investment management

    PubMed Central

    Kim, Hugh Hoikwang; Maurer, Raimond; Mitchell, Olivia S.

    2016-01-01

    Many households display inertia in investment management over their life cycles. Our calibrated dynamic life cycle portfolio choice model can account for such an apparently ‘irrational’ outcome, by incorporating the fact that investors must forgo acquiring job-specific skills when they spend time managing their money, and their efficiency in financial decision making varies with age. Resulting inertia patterns mesh well with findings from prior studies and our own empirical results from Panel Study of Income Dynamics (PSID) data. We also analyze how people optimally choose between actively managing their assets versus delegating the task to financial advisors. Delegation proves valuable to both the young and the old. Our calibrated model quantifies welfare gains from including investment time and money costs as well as delegation in a life cycle setting. PMID:28344380

  19. Effect of KOH concentration on LEO cycle life of IPV nickel-hydrogen flight cells-update 2

    NASA Technical Reports Server (NTRS)

    Smithrick, John J.; Hall, Stephen W.

    1991-01-01

    An update of validation test results confirming the breakthrough in low earth orbit (LEO) cycle life of nickel-hydrogen cells containing 26 percent KOH electrolyte is presented. A breakthrough in the LEO cycle life of individual pressure vessel (IPV nickel-hydrogen cells has been previously reported. The cycle life of boiler plate cells containing 26 percent potassium hydroxide (KOH) electrolyte was about 40 000 LEO cycles compared to 3500 cycles for cells containing 31 percent KOH. This test was conducted at Hughes Aircraft Company under a NASA Lewis contract. The purpose was to investigate the effect of KOH concentration on cycle life. The cycle regime was a stressful accelerated LEO, which consisted of a 27.5 min charge followed by a 17.5 min discharge (2x normal rate). The depth of discharge (DOD) was 80 percent. The cell temperature was maintained at 23 C. The boiler plate test results are in the process of being validated using flight hardware and real time LEO test at the Naval Weapons Support Center (NWSC), Crane, Indiana under a NASA Lewis Contract. Six 48 Ah Hughes recirculation design IPV nickel-hydrogen flight battery cells are being evaluated. Three of the cells contain 26 percent KOH (test cells), and three contain 31 percent KOH (control cells). They are undergoing real time LEO cycle life testing. The cycle regime is a 90-min LEO orbit consisting of a 54-min charge followed by a 36-min discharge. The depth-of-discharge is 80 percent. The cell temperature is maintained at 10 C. The three 31 percent KOH cells failed (cycles 3729, 4165, and 11355). One of the 26 percent KOH cells failed at cycle 15314. The other two 26 percent KOH cells were cycled for over 16600 cycles during the continuing test.

  20. Advanced Plant Habitat (APH)

    NASA Technical Reports Server (NTRS)

    Richards, Stephanie E. (Compiler); Levine, Howard G.; Reed, David W.

    2016-01-01

    The Advanced Plant Habitat (APH) hardware will be a large growth volume plant habitat, capable of hosting multigenerational studies, in which environmental variables (e.g., temperature, relative humidity, carbon dioxide level light intensity and spectral quality) can be tracked and controlled in support of whole plant physiological testing and Bio-regenerative Life Support System investigations.