Can niche plasticity promote biodiversity-productivity relationships through increased complementarity?

PubMed

Niklaus, Pascal A; Baruffol, Martin; He, Jin-Sheng; Ma, Keping; Schmid, Bernhard

2017-04-01

Most experimental biodiversity-ecosystem functioning research to date has addressed herbaceous plant communities. Comparably little is known about how forest communities will respond to species losses, despite their importance for global biogeochemical cycling. We studied tree species interactions in experimental subtropical tree communities with 33 distinct tree species mixtures and one, two, or four species. Plots were either exposed to natural light levels or shaded. Trees grew rapidly and were intensely competing above ground after 1.5 growing seasons when plots were thinned and the vertical distribution of leaves and wood determined by separating the biomass of harvested trees into 50 cm height increments. Our aim was to analyze effects of species richness in relation to the vertical allocation of leaf biomass and wood, with an emphasis on bipartite competitive interactions among species. Aboveground productivity increased with species richness. The community-level vertical leaf and wood distribution depended on the species composition of communities. Mean height and breadth of species-level vertical leaf and wood distributions did not change with species richness. However, the extra biomass produced by mixtures compared to monocultures of the component species increased when vertical leaf distributions of monocultures were more different. Decomposition of biodiversity effects with the additive partitioning scheme indicated positive complementarity effects that were higher in light than in shade. Selection effects did not deviate from zero, irrespective of light levels. Vertical leaf distributions shifted apart in mixed stands as consequence of competition-driven phenotypic plasticity, promoting realized complementarity. Structural equation models showed that this effect was larger for species that differed more in growth strategies that were characterized by functional traits. In 13 of the 18 investigated two-species mixtures, both species benefitted relative to intraspecific competition in monoculture. In the remaining five pairwise mixtures, the relative yield gain of one species exceeded the relative yield loss of the other species, resulting in a relative yield total (RYT) exceeding 1. Overall, our analysis indicates that richness-productivity relationships are promoted by interspecific niche complementarity at early stages of stand development, and that this effect is enhanced by architectural plasticity. © 2017 by the Ecological Society of America.

Complementarity between the Transfer Goals of Community Colleges and Historically Black Colleges and Universities: Learning from History

ERIC Educational Resources Information Center

Hughes, Bob

2012-01-01

Community colleges and historically Black colleges and universities (HBCUs) often serve the same populations; however, the historical purposes, policies, and practices of HBCUs often better prepare them to serve first-generation students. Although both HBCUs and community colleges have their origins within the same historical period, the forces…

Arbuscular mycorrhizal fungi and associated microbial communities from dry grassland do not improve plant growth on abandoned field soil.

PubMed

Pánková, Hana; Lepinay, Clémentine; Rydlová, Jana; Voříšková, Alena; Janoušková, Martina; Dostálek, Tomáš; Münzbergová, Zuzana

2018-03-01

After abandonment of agricultural fields, some grassland plant species colonize these sites with a frequency equivalent to dry grasslands (generalists) while others are missing or underrepresented in abandoned fields (specialists). We aimed to understand the inability of specialists to spread on abandoned fields by exploring whether performance of generalists and specialists depended on soil abiotic and/or biotic legacy. We performed a greenhouse experiment with 12 species, six specialists and six generalists. The plants were grown in sterile soil from dry grassland or abandoned field inoculated with microbial communities from one or the other site. Plant growth, abundance of mycorrhizal structures and plant response to inoculation were evaluated. We focused on arbuscular mycorrhizal fungi (AMF), one of the most important parts of soil communities affecting plant performance. The abandoned field soil negatively affected plant growth, but positively affected plant response to inoculation. The AMF community from both sites differed in infectivity and taxa frequencies. The lower AMF taxa frequency in the dry grassland soil suggested a lack of functional complementarity. Despite the fact that dry grassland AMF produced more arbuscules, the dry grassland inoculum did not improve phosphorus nutrition of specialists contrary to the abandoned field inoculum. Inoculum origin did not affect phosphorus nutrition of generalists. The lower effectiveness of the dry grassland microbial community toward plant performance excludes its inoculation in the abandoned field soil as a solution to allow settlement of specialists. Still, the distinct response of specialists and generalists to inoculation suggested that they differ in AMF responsiveness.

Investigating functional redundancy versus complementarity in Hawaiian herbivorous coral reef fishes.

PubMed

Kelly, Emily L A; Eynaud, Yoan; Clements, Samantha M; Gleason, Molly; Sparks, Russell T; Williams, Ivor D; Smith, Jennifer E

2016-12-01

Patterns of species resource use provide insight into the functional roles of species and thus their ecological significance within a community. The functional role of herbivorous fishes on coral reefs has been defined through a variety of methods, but from a grazing perspective, less is known about the species-specific preferences of herbivores on different groups of reef algae and the extent of dietary overlap across an herbivore community. Here, we quantified patterns of redundancy and complementarity in a highly diverse community of herbivores at a reef on Maui, Hawaii, USA. First, we tracked fish foraging behavior in situ to record bite rate and type of substrate bitten. Second, we examined gut contents of select herbivorous fishes to determine consumption at a finer scale. Finally, we placed foraging behavior in the context of resource availability to determine how fish selected substrate type. All species predominantly (73-100 %) foraged on turf algae, though there were differences among the types of macroalgae and other substrates bitten. Increased resolution via gut content analysis showed the composition of turf algae consumed by fishes differed across herbivore species. Consideration of foraging behavior by substrate availability revealed 50 % of herbivores selected for turf as opposed to other substrate types, but overall, there were variable foraging portfolios across all species. Through these three methods of investigation, we found higher complementarity among herbivorous fishes than would be revealed using a single metric. These results suggest differences across species in the herbivore "rain of bites" that graze and shape benthic community composition.

Evaluating the Economic and Social Benefits of Nutrient ...

EPA Pesticide Factsheets

New England’s coastal social-ecological systems are subject to chronic environmental problems, including water quality degradation. Researchers at EPA’s Office of Research and Development (ORD) Atlantic Ecology Division (AED) are piloting an effort to further understand how reduced water quality due to nutrient enrichment is affecting and may affect the economic prosperity, social capacity, and ecological integrity of coastal New England communities. This research is part of task 4.61 of ORD’s Sustainable and Healthy Communities Research Program (Integrated Solutions for Sustainable Communities: Social-Ecological Systems for Resilience and Adaptive Management in Communities - A Cape Cod Case Study). Concurrent with this effort, AED researchers are participating in EPA’s three-office effort (Office of Research and Development, Office of Policy, and Office of Water) to quantify and monetize the benefits of water quality improvements across the Nation. AED’s effort is a case study of changes in recreation demand and values due to changes in nutrients in Northeastern estuaries and freshwater ponds. This work is part of task 3.04A of the Safe and Sustainable Waters Research Program (National Water Quality Benefits: Economic Case Studies of Water Quality Benefits). Because of the complementarity between the two projects, this Supporting Statement describes and requests hours for focus groups and interviews for both of these research efforts. Our initial

Is the firewall consistent? Gedanken experiments on black hole complementarity and firewall proposal

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

Hwang, Dong-il; Lee, Bum-Hoon; Yeom, Dong-han, E-mail: dongil.j.hwang@gmail.com, E-mail: bhl@sogang.ac.kr, E-mail: innocent.yeom@gmail.com

2013-01-01

In this paper, we discuss the black hole complementarity and the firewall proposal at length. Black hole complementarity is inevitable if we assume the following five things: unitarity, entropy-area formula, existence of an information observer, semi-classical quantum field theory for an asymptotic observer, and the general relativity for an in-falling observer. However, large N rescaling and the AMPS argument show that black hole complementarity is inconsistent. To salvage the basic philosophy of the black hole complementarity, AMPS introduced a firewall around the horizon. According to large N rescaling, the firewall should be located close to the apparent horizon. We investigatemore » the consistency of the firewall with the two critical conditions: the firewall should be near the time-like apparent horizon and it should not affect the future infinity. Concerning this, we have introduced a gravitational collapse with a false vacuum lump which can generate a spacetime structure with disconnected apparent horizons. This reveals a situation that there is a firewall outside of the event horizon, while the apparent horizon is absent. Therefore, the firewall, if it exists, not only does modify the general relativity for an in-falling observer, but also modify the semi-classical quantum field theory for an asymptotic observer.« less

Is the firewall consistent? Gedanken experiments on black hole complementarity and firewall proposal

NASA Astrophysics Data System (ADS)

Hwang, Dong-il; Lee, Bum-Hoon; Yeom, Dong-han

2013-01-01

In this paper, we discuss the black hole complementarity and the firewall proposal at length. Black hole complementarity is inevitable if we assume the following five things: unitarity, entropy-area formula, existence of an information observer, semi-classical quantum field theory for an asymptotic observer, and the general relativity for an in-falling observer. However, large N rescaling and the AMPS argument show that black hole complementarity is inconsistent. To salvage the basic philosophy of the black hole complementarity, AMPS introduced a firewall around the horizon. According to large N rescaling, the firewall should be located close to the apparent horizon. We investigate the consistency of the firewall with the two critical conditions: the firewall should be near the time-like apparent horizon and it should not affect the future infinity. Concerning this, we have introduced a gravitational collapse with a false vacuum lump which can generate a spacetime structure with disconnected apparent horizons. This reveals a situation that there is a firewall outside of the event horizon, while the apparent horizon is absent. Therefore, the firewall, if it exists, not only does modify the general relativity for an in-falling observer, but also modify the semi-classical quantum field theory for an asymptotic observer.

Character displacement and the evolution of niche complementarity in a model biofilm community.

PubMed

Ellis, Crystal N; Traverse, Charles C; Mayo-Smith, Leslie; Buskirk, Sean W; Cooper, Vaughn S

2015-02-01

Colonization of vacant environments may catalyze adaptive diversification and be followed by competition within the nascent community. How these interactions ultimately stabilize and affect productivity are central problems in evolutionary ecology. Diversity can emerge by character displacement, in which selection favors phenotypes that exploit an alternative resource and reduce competition, or by facilitation, in which organisms change the environment and enable different genotypes or species to become established. We previously developed a model of long-term experimental evolution in which bacteria attach to a plastic bead, form a biofilm, and disperse to a new bead. Here, we focus on the evolution of coexisting mutants within a population of Burkholderia cenocepacia and how their interactions affected productivity. Adaptive mutants initially competed for space, but later competition declined, consistent with character displacement and the predicted effects of the evolved mutations. The community reached a stable equilibrium as each ecotype evolved to inhabit distinct, complementary regions of the biofilm. Interactions among ecotypes ultimately became facilitative and enhanced mixed productivity. Observing the succession of genotypes within niches illuminated changing selective forces within the community, including a fundamental role for genotypes producing small colony variants that underpin chronic infections caused by B. cenocepacia. © 2014 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Complementarity among four highly productive grassland species depends on resource availability.

PubMed

Roscher, Christiane; Schmid, Bernhard; Kolle, Olaf; Schulze, Ernst-Detlef

2016-06-01

Positive species richness-productivity relationships are common in biodiversity experiments, but how resource availability modifies biodiversity effects in grass-legume mixtures composed of highly productive species is yet to be explicitly tested. We addressed this question by choosing two grasses (Arrhenatherum elatius and Dactylis glomerata) and two legumes (Medicago × varia and Onobrychis viciifolia) which are highly productive in monocultures and dominant in mixtures (the Jena Experiment). We established monocultures, all possible two- and three-species mixtures, and the four-species mixture under three different resource supply conditions (control, fertilization, and shading). Compared to the control, community biomass production decreased under shading (-56 %) and increased under fertilization (+12 %). Net diversity effects (i.e., mixture minus mean monoculture biomass) were positive in the control and under shading (on average +15 and +72 %, respectively) and negative under fertilization (-10 %). Positive complementarity effects in the control suggested resource partitioning and facilitation of growth through symbiotic N2 fixation by legumes. Positive complementarity effects under shading indicated that resource partitioning is also possible when growth is carbon-limited. Negative complementarity effects under fertilization suggested that external nutrient supply depressed facilitative grass-legume interactions due to increased competition for light. Selection effects, which quantify the dominance of species with particularly high monoculture biomasses in the mixture, were generally small compared to complementarity effects, and indicated that these species had comparable competitive strengths in the mixture. Our study shows that resource availability has a strong impact on the occurrence of positive diversity effects among tall and highly productive grass and legume species.

Phytoplankton Assemblage Characteristics in Recurrently Fluctuating Environments

PubMed Central

Roelke, Daniel L.; Spatharis, Sofie

2015-01-01

Annual variations in biogeochemical and physical processes can lead to nutrient variability and seasonal patterns in phytoplankton productivity and assemblage structure. In many coastal systems river inflow and water exchange with the ocean varies seasonally, and alternating periods can arise where the nutrient most limiting to phytoplankton growth switches. Transitions between these alternating periods can be sudden or gradual and this depends on human activities, such as reservoir construction and interbasin water transfers. How such activities might influence phytoplankton assemblages is largely unknown. Here, we employed a multispecies, multi-nutrient model to explore how nutrient loading switching mode might affect characteristics of phytoplankton assemblages. The model is based on the Monod-relationship, predicting an instantaneous growth rate from ambient inorganic nutrient concentrations whereas the limiting nutrient at any given time was determined by Liebig’s Law of the Minimum. Our simulated phytoplankton assemblages self-organized from species rich pools over a 15-year period, and only the surviving species were considered as assemblage members. Using the model, we explored the interactive effects of complementarity level in trait trade-offs within phytoplankton assemblages and the amount of noise in the resource supply concentrations. We found that the effect of shift from a sudden resource supply transition to a gradual one, as observed in systems impacted by watershed development, was dependent on the level of complementarity. In the extremes, phytoplankton species richness and relative overyielding increased when complementarity was lowest, and phytoplankton biomass increased greatly when complementarity was highest. For low-complementarity simulations, the persistence of poorer-performing phytoplankton species of intermediate R*s led to higher richness and relative overyielding. For high-complementarity simulations, the formation of phytoplankton species clusters and niche compression enabled higher biomass accumulation. Our findings suggest that an understanding of factors influencing the emergence of life history traits important to complementarity is necessary to predict the impact of watershed development on phytoplankton productivity and assemblage structure. PMID:25799563

Evaluating complementary networks of restoration plantings for landscape-scale occurrence of temporally dynamic species.

PubMed

Ikin, Karen; Tulloch, Ayesha; Gibbons, Philip; Ansell, Dean; Seddon, Julian; Lindenmayer, David

2016-10-01

Multibillion dollar investments in land restoration make it critical that conservation goals are achieved cost-effectively. Approaches developed for systematic conservation planning offer opportunities to evaluate landscape-scale, temporally dynamic biodiversity outcomes from restoration and improve on traditional approaches that focus on the most species-rich plantings. We investigated whether it is possible to apply a complementarity-based approach to evaluate the extent to which an existing network of restoration plantings meets representation targets. Using a case study of woodland birds of conservation concern in southeastern Australia, we compared complementarity-based selections of plantings based on temporally dynamic species occurrences with selections based on static species occurrences and selections based on ranking plantings by species richness. The dynamic complementarity approach, which incorporated species occurrences over 5 years, resulted in higher species occurrences and proportion of targets met compared with the static complementarity approach, in which species occurrences were taken at a single point in time. For equivalent cost, the dynamic complementarity approach also always resulted in higher average minimum percent occurrence of species maintained through time and a higher proportion of the bird community meeting representation targets compared with the species-richness approach. Plantings selected under the complementarity approaches represented the full range of planting attributes, whereas those selected under the species-richness approach were larger in size. Our results suggest that future restoration policy should not attempt to achieve all conservation goals within individual plantings, but should instead capitalize on restoration opportunities as they arise to achieve collective value of multiple plantings across the landscape. Networks of restoration plantings with complementary attributes of age, size, vegetation structure, and landscape context lead to considerably better outcomes than conventional restoration objectives of site-scale species richness and are crucial for allocating restoration investment wisely to reach desired conservation goals. © 2016 Society for Conservation Biology.

Does species diversity limit productivity in natural grassland communities?

USGS Publications Warehouse

Grace, J.B.; Anderson, T.M.; Smith, M.D.; Seabloom, E.; Andelman, S.J.; Meche, G.; Weiher, E.; Allain, L.K.; Jutila, H.; Sankaran, M.; Knops, J.; Ritchie, M.; Willig, M.R.

2007-01-01

Theoretical analyses and experimental studies of synthesized assemblages indicate that under particular circumstances species diversity can enhance community productivity through niche complementarity. It remains unclear whether this process has important effects in mature natural ecosystems where competitive feedbacks and complex environmental influences affect diversity-productivity relationships. In this study, we evaluated diversity-productivity relationships while statistically controlling for environmental influences in 12 natural grassland ecosystems. Because diversity-productivity relationships are conspicuously nonlinear, we developed a nonlinear structural equation modeling (SEM) methodology to separate the effects of diversity on productivity from the effects of productivity on diversity. Meta-analysis was used to summarize the SEM findings across studies. While competitive effects were readily detected, enhancement of production by diversity was not. These results suggest that the influence of small-scale diversity on productivity in mature natural systems is a weak force, both in absolute terms and relative to the effects of other controls on productivity. ?? 2007 Blackwell Publishing Ltd/CNRS.

Understanding and planning ecological restoration of plant-pollinator networks.

PubMed

Devoto, Mariano; Bailey, Sallie; Craze, Paul; Memmott, Jane

2012-04-01

Theory developed from studying changes in the structure and function of communities during natural or managed succession can guide the restoration of particular communities. We constructed 30 quantitative plant-flower visitor networks along a managed successional gradient to identify the main drivers of change in network structure. We then applied two alternative restoration strategies in silico (restoring for functional complementarity or redundancy) to data from our early successional plots to examine whether different strategies affected the restoration trajectories. Changes in network structure were explained by a combination of age, tree density and variation in tree diameter, even when variance explained by undergrowth structure was accounted for first. A combination of field data, a network approach and numerical simulations helped to identify which species should be given restoration priority in the context of different restoration targets. This combined approach provides a powerful tool for directing management decisions, particularly when management seeks to restore or conserve ecosystem function. © 2012 Blackwell Publishing Ltd/CNRS.

Intraspecific genetic diversity and composition modify species-level diversity-productivity relationships.

PubMed

Schöb, Christian; Kerle, Sarah; Karley, Alison J; Morcillo, Luna; Pakeman, Robin J; Newton, Adrian C; Brooker, Rob W

2015-01-01

Biodiversity regulates ecosystem functions such as productivity, and experimental studies of species mixtures have revealed selection and complementarity effects driving these responses. However, the impacts of intraspecific genotypic diversity in these studies are unknown, despite it forming a substantial part of the biodiversity. In a glasshouse experiment we constructed plant communities with different levels of barley (Hordeum vulgare) genotype and weed species diversity and assessed their relative biodiversity effects through additive partitioning into selection and complementarity effects. Barley genotype diversity had weak positive effects on aboveground biomass through complementarity effects, whereas weed species diversity increased biomass predominantly through selection effects. When combined, increasing genotype diversity of barley tended to dilute the selection effect of weeds. We interpret these different effects of barley genotype and weed species diversity as the consequence of small vs large trait variation associated with intraspecific barley diversity and interspecific weed diversity, respectively. The different effects of intra- vs interspecific diversity highlight the underestimated and overlooked role of genetic diversity for ecosystem functioning. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

Selection for niche differentiation in plant communities increases biodiversity effects.

PubMed

Zuppinger-Dingley, Debra; Schmid, Bernhard; Petermann, Jana S; Yadav, Varuna; De Deyn, Gerlinde B; Flynn, Dan F B

2014-11-06

In experimental plant communities, relationships between biodiversity and ecosystem functioning have been found to strengthen over time, a fact often attributed to increased resource complementarity between species in mixtures and negative plant-soil feedbacks in monocultures. Here we show that selection for niche differentiation between species can drive this increasing biodiversity effect. Growing 12 grassland species in test monocultures and mixtures, we found character displacement between species and increased biodiversity effects when plants had been selected over 8 years in species mixtures rather than in monocultures. When grown in mixtures, relative differences in height and specific leaf area between plant species selected in mixtures (mixture types) were greater than between species selected in monocultures (monoculture types). Furthermore, net biodiversity and complementarity effects were greater in mixtures of mixture types than in mixtures of monoculture types. Our study demonstrates a novel mechanism for the increase in biodiversity effects: selection for increased niche differentiation through character displacement. Selection in diverse mixtures may therefore increase species coexistence and ecosystem functioning in natural communities and may also allow increased mixture yields in agriculture or forestry. However, loss of biodiversity and prolonged selection of crops in monoculture may compromise this potential for selection in the longer term.

Spider Communities and Biological Control in Native Habitats Surrounding Greenhouses.

PubMed

Cotes, Belén; González, Mónica; Benítez, Emilio; De Mas, Eva; Clemente-Orta, Gemma; Campos, Mercedes; Rodríguez, Estefanía

2018-03-14

The promotion of native vegetation as a habitat for natural enemies, which could increase their abundance and fitness, is especially useful in highly simplified settings such as Mediterranean greenhouse landscapes. Spiders as generalist predators may also be involved in intra-guild predation. However, the niche complementarity provided by spiders as a group means that increased spider diversity may facilitate complementary control actions. In this study, the interactions between spiders, the two major horticultural pests, Bemisia tabaci and Frankliniella occidentalis , and their naturally occurring predators and parasitoids were evaluated in a mix of 21 newly planted shrubs selected for habitat management in a highly disturbed horticultural system. The effects of all factors were evaluated using redundancy analysis (RDA) and the generalized additive model (GAM) to assess the statistical significance of abundance of spiders and pests. The GAM showed that the abundance of both pests had a significant effect on hunter spider's abundance, whereas the abundance of B. tabaci , but not F. occidentalis , affected web-weavers' abundance. Ordination analysis showed that spider abundance closely correlated with that of B. tabaci but not with that of F. occidentalis , suggesting that complementarity occurs, and thereby probability of biocontrol, with respect to the targeted pest B. tabaci , although the temporal patterns of the spiders differed from those of F. occidentalis . Conservation strategies involving the establishment of these native plants around greenhouses could be an effective way to reduce pest populations outdoors.

Across species-pool aggregation alters grassland productivity and diversity.

PubMed

McKenna, Thomas P; Yurkonis, Kathryn A

2016-08-01

Plant performance is determined by the balance of intra- and interspecific neighbors within an individual's zone of influence. If individuals interact over smaller scales than the scales at which communities are measured, then altering neighborhood interactions may fundamentally affect community responses. These interactions can be altered by changing the number (species richness), abundances (species evenness), and positions (species pattern) of the resident plant species, and we aimed to test whether aggregating species at planting would alter effects of species richness and evenness on biomass production at a common scale of observation in grasslands. We varied plant species richness (2, 4, or 8 species and monocultures), evenness (0.64, 0.8, or 1.0), and pattern (planted randomly or aggregated in groups of four individuals) within 1 × 1 m plots established with transplants from a pool of 16 tallgrass prairie species and assessed plot-scale biomass production and diversity over the first three growing seasons. As expected, more species-rich plots produced more biomass by the end of the third growing season, an effect associated with a shift from selection to complementarity effects over time. Aggregating conspecifics at a 0.25-m scale marginally reduced biomass production across all treatments and increased diversity in the most even plots, but did not alter biodiversity effects or richness-productivity relationships. Results support the hypothesis that fine-scale species aggregation affects diversity by promoting species coexistence in this system. However, results indicate that inherent changes in species neighborhood relationships along grassland diversity gradients may only minimally affect community (meter) - scale responses among similarly designed biodiversity-ecosystem function studies. Given that species varied in their responses to local aggregation, it may be possible to use such species-specific results to spatially design larger-scale grassland communities to achieve desired diversity and productivity responses.

Tree species diversity promotes aboveground carbon storage through functional diversity and functional dominance.

PubMed

Mensah, Sylvanus; Veldtman, Ruan; Assogbadjo, Achille E; Glèlè Kakaï, Romain; Seifert, Thomas

2016-10-01

The relationship between biodiversity and ecosystem function has increasingly been debated as the cornerstone of the processes behind ecosystem services delivery. Experimental and natural field-based studies have come up with nonconsistent patterns of biodiversity-ecosystem function, supporting either niche complementarity or selection effects hypothesis. Here, we used aboveground carbon (AGC) storage as proxy for ecosystem function in a South African mistbelt forest, and analyzed its relationship with species diversity, through functional diversity and functional dominance. We hypothesized that (1) diversity influences AGC through functional diversity and functional dominance effects; and (2) effects of diversity on AGC would be greater for functional dominance than for functional diversity. Community weight mean (CWM) of functional traits (wood density, specific leaf area, and maximum plant height) were calculated to assess functional dominance (selection effects). As for functional diversity (complementarity effects), multitrait functional diversity indices were computed. The first hypothesis was tested using structural equation modeling. For the second hypothesis, effects of environmental variables such as slope and altitude were tested first, and separate linear mixed-effects models were fitted afterward for functional diversity, functional dominance, and both. Results showed that AGC varied significantly along the slope gradient, with lower values at steeper sites. Species diversity (richness) had positive relationship with AGC, even when slope effects were considered. As predicted, diversity effects on AGC were mediated through functional diversity and functional dominance, suggesting that both the niche complementarity and the selection effects are not exclusively affecting carbon storage. However, the effects were greater for functional diversity than for functional dominance. Furthermore, functional dominance effects were strongly transmitted by CWM of maximum plant height, reflecting the importance of forest vertical stratification for diversity-carbon relationship. We therefore argue for stronger complementary effects that would be induced also by complementary light-use efficiency of tree and species growing in the understory layer.

Biomass is the main driver of changes in ecosystem process rates during tropical forest succession.

PubMed

Lohbeck, Madelon; Poorter, Lourens; Martínez-Ramos, Miguel; Bongers, Frans

2015-05-01

Over half of the world's forests are disturbed, and the rate at which ecosystem processes recover after disturbance is important for the services these forests can provide. We analyze the drivers' underlying changes in rates of key ecosystem processes (biomass productivity, litter productivity, actual litter decomposition, and potential litter decomposition) during secondary succession after shifting cultivation in wet tropical forest of Mexico. We test the importance of three alternative drivers of ecosystem processes: vegetation biomass (vegetation quantity hypothesis), community-weighted trait mean (mass ratio hypothesis), and functional diversity (niche complementarity hypothesis) using structural equation modeling. This allows us to infer the relative importance of different mechanisms underlying ecosystem process recovery. Ecosystem process rates changed during succession, and the strongest driver was aboveground biomass for each of the processes. Productivity of aboveground stem biomass and leaf litter as well as actual litter decomposition increased with initial standing vegetation biomass, whereas potential litter decomposition decreased with standing biomass. Additionally, biomass productivity was positively affected by community-weighted mean of specific leaf area, and potential decomposition was positively affected by functional divergence, and negatively by community-weighted mean of leaf dry matter content. Our empirical results show that functional diversity and community-weighted means are of secondary importance for explaining changes in ecosystem process rates during tropical forest succession. Instead, simply, the amount of vegetation in a site is the major driver of changes, perhaps because there is a steep biomass buildup during succession that overrides more subtle effects of community functional properties on ecosystem processes. We recommend future studies in the field of biodiversity and ecosystem functioning to separate the effects of vegetation quality (community-weighted mean trait values and functional diversity) from those of vegetation quantity (biomass) on ecosystem processes and services.

Shining Light on Benthic Macroalgae: Mechanisms of Complementarity in Layered Macroalgal Assemblages

PubMed Central

Tait, Leigh W.; Hawes, Ian; Schiel, David R.

2014-01-01

Phototrophs underpin most ecosystem processes, but to do this they need sufficient light. This critical resource, however, is compromised along many marine shores by increased loads of sediments and nutrients from degraded inland habitats. Increased attenuation of total irradiance within coastal water columns due to turbidity is known to reduce species' depth limits and affect the taxonomic structure and architecture of algal-dominated assemblages, but virtually no attention has been paid to the potential for changes in spectral quality of light energy to impact production dynamics. Pioneering studies over 70 years ago showed how different pigmentation of red, green and brown algae affected absorption spectra, action spectra, and photosynthetic efficiency across the PAR (photosynthetically active radiation) spectrum. Little of this, however, has found its way into ecological syntheses of the impacts of optically active contaminants on coastal macroalgal communities. Here we test the ability of macroalgal assemblages composed of multiple functional groups (including representatives from the chlorophyta, rhodophyta and phaeophyta) to use the total light resource, including different light wavelengths and examine the effects of suspended sediments on the penetration and spectral quality of light in coastal waters. We show that assemblages composed of multiple functional groups are better able to use light throughout the PAR spectrum. Macroalgal assemblages with four sub-canopy species were between 50–75% more productive than assemblages with only one or two sub-canopy species. Furthermore, attenuation of the PAR spectrum showed both a loss of quanta and a shift in spectral distribution with depth across coastal waters of different clarity, with consequences to productivity dynamics of diverse layered assemblages. The processes of light complementarity may help provide a mechanistic understanding of how altered turbidity affects macroalgal assemblages in coastal waters, which are increasingly threatened by diminishing light quantity and altered spectral distributions through sedimentation and eutrophication. PMID:25438045

Mobilization of interactions between functional diversity of plant and soil organisms on nitrogen availability and use

NASA Astrophysics Data System (ADS)

Drut, Baptiste; Cassagne, Nathalie; Cannavacciuolo, Mario; Brauman, Alain; Le Floch, Gaëtan; Cobo, Jose; Fustec, Joëlle

2017-04-01

Keywords: legumes, earthworms, microorganisms, nitrogen, interactions Both aboveground and belowground biodiversity and their interactions can play an important role in crop productivity. Plant functional diversity, such as legume based intercrops have been shown to improve yields through plant complementarity for nitrogen use (Corre-Hellou et al., 2006). Moreover, plant species or plant genotype may influence the structure of soil microorganism communities through the composition of rhizodeposits in the rhizosphere (Dennis et al., 2010). Belowground diversity can also positively influence plant performance especially related to functional dissimilarity between soil organisms (Eisenhauer, 2012). Earthworms through their burrowing activity influence soil microbial decomposers and nutrient availability and have thus been reported to increase plant growth (Brown, 1995; Brown et al., 2004). We hypothesize that i) plant functional (genetic and/or specific) diversity associated to functional earthworms diversity are key drivers of interactions balance to improve crop performances and ii) the improvement of plant performances can be related to change in the structure of soil microorganism communities due to the diversity of rhizodeposits and the burrowing activity of earthworms. In a first mesocosm experiment, we investigated the effect of a gradient of plant diversity - one cultivar of wheat (Triticum aestivum L.), 3 different wheat cultivars, and 3 different cultivars intercropped with clover (Trifolium hybridum L.) - and the presence of one (endogeic) or two (endogeic and anecic) categories of earthworms on biomass and nitrogen accumulation of wheat. In a second mesocosm experiment, we investigated the influence of three species with different rhizodeposition - wheat, rapeseed (Brassica napus L. ) and faba bean (Vicia faba L.) in pure stand or intercropped - and the presence of endogeic earthworms on microbial activity and nitrogen availability. In the first experiment, biomass and nitrogen accumulation of wheat were improved in the presence of earthworms and clover. No effect of a plant genetic diversity was shown on crop performances. Furthermore, the influence of earthworms on bacterial diversity depended on plant diversity. In the second experiment, the specific composition of plant and earthworm presence modified the physiological profiles of rhizospheric microorganism communities (Microresp®) and nitrification potential. In the presence of faba-bean, microorganism activity was consistently increased and earthworms tended to decrease C:N ratio in the rhizospheric soil. These results confirm the interest of legume based intercrops for the complementarity in nitrogen use thanks to biological fixation. This study showed the influence of earthworms on plant nitrogen acquisition by stimulating microorganism activity and nutrient availability around the roots. We also highlighted a synergistic effect between the presence of legume and endogeic earthworms for higher plant performances. We finally hypothesized that the combined effect of rhizodeposit diversity related to plant specific composition and soil chemical properties modified by earthworm activity drives the structure and activity of microorganism communities. Brown, G.G., 1995. How do earthworms affect microfloral and faunal community diversity? Plant and Soil 170, 209-231. Brown, G.G., Edwards, C.A., Brussaard, L., 2004. How earthworms affect plant growth: burrowing into the mechanisms. Earthworm ecology 2, 13-49. Corre-Hellou, G., Fustec, J., Crozat, Y., 2006. Interspecific competition for soil N and its interaction with N2 fixation, leaf expansion and crop growth in pea-barley intercrops. Plant and Soil 282, 195-208. Dennis, P.G., Miller, A.J., Hirsch, P.R., 2010. Are root exudates more important than other sources of rhizodeposits in structuring rhizosphere bacterial communities? FEMS Microbiology Ecology 72, 313-327. Eisenhauer, N., 2012. Aboveground-belowground interactions as a source of complementarity effects in biodiversity experiments. Plant and Soil 351, 1-22.

Multitrophic functional diversity predicts ecosystem functioning in experimental assemblages of estuarine consumers.

PubMed

Lefcheck, Jonathan S; Duffy, J Emmett

2015-11-01

The use of functional traits to explain how biodiversity affects ecosystem functioning has attracted intense interest, yet few studies have a priori altered functional diversity, especially in multitrophic communities. Here, we manipulated multivariate functional diversity of estuarine grazers and predators within multiple levels of species richness to test how species richness and functional diversity predicted ecosystem functioning in a multitrophic food web. Community functional diversity was a better predictor than species richness for the majority of ecosystem properties, based on generalized linear mixed-effects models. Combining inferences from eight traits into a single multivariate index increased prediction accuracy of these models relative to any individual trait. Structural equation modeling revealed that functional diversity of both grazers and predators was important in driving final biomass within trophic levels, with stronger effects observed for predators. We also show that different species drove different ecosystem responses, with evidence for both sampling effects and complementarity. Our study extends experimental investigations of functional trait diversity to a multilevel food web, and demonstrates that functional diversity can be more accurate and effective than species richness in predicting community biomass in a food web context.

Resilience and stability of a pelagic marine ecosystem

PubMed Central

Lindegren, Martin; Checkley, David M.; Ohman, Mark D.; Koslow, J. Anthony; Goericke, Ralf

2016-01-01

The accelerating loss of biodiversity and ecosystem services worldwide has accentuated a long-standing debate on the role of diversity in stabilizing ecological communities and has given rise to a field of research on biodiversity and ecosystem functioning (BEF). Although broad consensus has been reached regarding the positive BEF relationship, a number of important challenges remain unanswered. These primarily concern the underlying mechanisms by which diversity increases resilience and community stability, particularly the relative importance of statistical averaging and functional complementarity. Our understanding of these mechanisms relies heavily on theoretical and experimental studies, yet the degree to which theory adequately explains the dynamics and stability of natural ecosystems is largely unknown, especially in marine ecosystems. Using modelling and a unique 60-year dataset covering multiple trophic levels, we show that the pronounced multi-decadal variability of the Southern California Current System (SCCS) does not represent fundamental changes in ecosystem functioning, but a linear response to key environmental drivers channelled through bottom-up and physical control. Furthermore, we show strong temporal asynchrony between key species or functional groups within multiple trophic levels caused by opposite responses to these drivers. We argue that functional complementarity is the primary mechanism reducing community variability and promoting resilience and stability in the SCCS. PMID:26763697

New Existence Conditions for Order Complementarity Problems

NASA Astrophysics Data System (ADS)

Németh, S. Z.

2009-09-01

Complementarity problems are mathematical models of problems in economics, engineering and physics. A special class of complementarity problems are the order complementarity problems [2]. Order complementarity problems can be applied in lubrication theory [6] and economics [1]. The notion of exceptional family of elements for general order complementarity problems in Banach spaces will be introduced. It will be shown that for general order complementarity problems defined by completely continuous fields the problem has either a solution or an exceptional family of elements (for other notions of exceptional family of elements see [1, 2, 3, 4] and the related references therein). This solves a conjecture of [2] about the existence of exceptional family of elements for order complementarity problems. The proof can be done by using the Leray-Schauder alternative [5]. An application to integral operators will be given.

Oxidation in the complementarity-determining regions differentially influences the properties of therapeutic antibodies

PubMed Central

Dashivets, Tetyana; Stracke, Jan; Dengl, Stefan; Knaupp, Alexander; Pollmann, Jan; Buchner, Johannes; Schlothauer, Tilman

2016-01-01

ABSTRACT Therapeutic antibodies can undergo a variety of chemical modification reactions in vitro. Depending on the site of modification, either antigen binding or Fc-mediated functions can be affected. Oxidation of tryptophan residues is one of the post-translational modifications leading to altered antibody functionality. In this study, we examined the structural and functional properties of a therapeutic antibody construct and 2 affinity matured variants thereof. Two of the 3 antibodies carry an oxidation-prone tryptophan residue in the complementarity-determining region of the VL domain. We demonstrate the differences in the stability and bioactivity of the 3 antibodies, and reveal differential degradation pathways for the antibodies susceptible to oxidation. PMID:27612038

Testing Associations of Plant Functional Diversity with Carbon and Nitrogen Storage along a Restoration Gradient of Sandy Grassland

PubMed Central

Zuo, Xiaoan; Zhou, Xin; Lv, Peng; Zhao, Xueyong; Zhang, Jing; Wang, Shaokun; Yue, Xiyuan

2016-01-01

The trait-based approach shows that ecosystem function is strongly affected by plant functional diversity as reflected by the traits of the most abundant species (community-weighted mean, CWM) and functional dispersion (FDis). Effects of CWM and FDis individually support the biomass ratio hypothesis and the niche complementarity hypothesis. However, there is little empirical evidence on the relative roles of CWM traits and FDis in explaining the carbon (C) and nitrogen (N) storage in grassland ecosystems. We measured plant functional traits in the 34 most abundant species across 24 sites along a restoration gradient of sandy grassland (mobile dune, semi-fixed dune, fixed dune, and grassland) in Horqin Sand Land, northern China. Thereafter, we calculated the CWM traits, the functional divergence of each single trait (FDvar) and the trait dispersion of multiple traits (FDis). We also measured the C and N storage in plant, litter, root, and soil. Using a stepwise multiple regression analysis, we further assessed which of the functional diversity components best explained C and N storage in the sandy grassland restoration. We found consistent links between C or N storage and leaf traits related to plant resource use strategy. However, the CWM of plant height was retained as an important predictor of C and N storage in plant, litter, soil, and total ecosystem in the final multiple models. CWMs of specific leaf area and plant height best predicted soil C and N storage and total ecosystem N storage. FDis was one of good predictors of litter C and N storage as well as total ecosystem C storage. These results suggest that ecosystem C and N pools in the sandy grassland restoration are primarily associated with the traits of the most abundant species in communities, thereby supporting the biomass ratio hypothesis. The positive associations of FDis with C storage in litter and total ecosystem provide evidence to support the niche complementarity hypothesis. Both functional traits of dominant species and traits’ dispersion in plant communities could contribute to explaining total ecosystem C storage. Thus, single- and multi-trait indices of functional composition play a crucial role in predicting C storage in sandy grasslands. PMID:26925089

Biomass production in experimental grasslands of different species richness during three years of climate warming

NASA Astrophysics Data System (ADS)

de Boeck, H. J.; Lemmens, C. M. H. M.; Zavalloni, C.; Gielen, B.; Malchair, S.; Carnol, M.; Merckx, R.; van den Berge, J.; Ceulemans, R.; Nijs, I.

2008-04-01

Here we report on the single and combined impacts of climate warming and species richness on the biomass production in experimental grassland communities. Projections of a future warmer climate have stimulated studies on the response of terrestrial ecosystems to this global change. Experiments have likewise addressed the importance of species numbers for ecosystem functioning. There is, however, little knowledge on the interplay between warming and species richness. During three years, we grew experimental plant communities containing one, three or nine grassland species in 12 sunlit, climate-controlled chambers in Wilrijk, Belgium. Half of these chambers were exposed to ambient air temperatures (unheated), while the other half were warmed by 3°C (heated). Equal amounts of water were added to heated and unheated communities, so that warming would imply drier soils if evapotranspiration was higher. Biomass production was decreased due to warming, both aboveground (-29%) and belowground (-25%), as negative impacts of increased heat and drought stress in summer prevailed. Complementarity effects, likely mostly through both increased aboveground spatial complementarity and facilitative effects of legumes, led to higher shoot and root biomass in multi-species communities, regardless of the induced warming. Surprisingly, warming suppressed productivity the most in 9-species communities, which may be attributed to negative impacts of intense interspecific competition for resources under conditions of high abiotic stress. Our results suggest that warming and the associated soil drying could reduce primary production in many temperate grasslands, and that this will not necessarily be mitigated by efforts to maintain or increase species richness.

Realistic diversity loss and variation in soil depth independently affect community-level plant nitrogen use.

PubMed

Selmants, Paul C; Zavaleta, Erika S; Wolf, Amelia A

2014-01-01

Numerous experiments have demonstrated that diverse plant communities use nitrogen (N) more completely and efficiently, with implications for how species conservation efforts might influence N cycling and retention in terrestrial ecosystems. However, most such experiments have randomly manipulated species richness and minimized environmental heterogeneity, two design aspects that may reduce applicability to real ecosystems. Here we present results from an experiment directly comparing how realistic and randomized plant species losses affect plant N use across a gradient of soil depth in a native-dominated serpentine grassland in California. We found that the strength of the species richness effect on plant N use did not increase with soil depth in either the realistic or randomized species loss scenarios, indicating that the increased vertical heterogeneity conferred by deeper soils did not lead to greater complementarity among species in this ecosystem. Realistic species losses significantly reduced plant N uptake and altered N-use efficiency, while randomized species losses had no effect on plant N use. Increasing soil depth positively affected plant N uptake in both loss order scenarios but had a weaker effect on plant N use than did realistic species losses. Our results illustrate that realistic species losses can have functional consequences that differ distinctly from randomized losses, and that species diversity effects can be independent of and outweigh those of environmental heterogeneity on ecosystem functioning. Our findings also support the value of conservation efforts aimed at maintaining biodiversity to help buffer ecosystems against increasing anthropogenic N loading.

NetCooperate: a network-based tool for inferring host-microbe and microbe-microbe cooperation.

PubMed

Levy, Roie; Carr, Rogan; Kreimer, Anat; Freilich, Shiri; Borenstein, Elhanan

2015-05-17

Host-microbe and microbe-microbe interactions are often governed by the complex exchange of metabolites. Such interactions play a key role in determining the way pathogenic and commensal species impact their host and in the assembly of complex microbial communities. Recently, several studies have demonstrated how such interactions are reflected in the organization of the metabolic networks of the interacting species, and introduced various graph theory-based methods to predict host-microbe and microbe-microbe interactions directly from network topology. Using these methods, such studies have revealed evolutionary and ecological processes that shape species interactions and community assembly, highlighting the potential of this reverse-ecology research paradigm. NetCooperate is a web-based tool and a software package for determining host-microbe and microbe-microbe cooperative potential. It specifically calculates two previously developed and validated metrics for species interaction: the Biosynthetic Support Score which quantifies the ability of a host species to supply the nutritional requirements of a parasitic or a commensal species, and the Metabolic Complementarity Index which quantifies the complementarity of a pair of microbial organisms' niches. NetCooperate takes as input a pair of metabolic networks, and returns the pairwise metrics as well as a list of potential syntrophic metabolic compounds. The Biosynthetic Support Score and Metabolic Complementarity Index provide insight into host-microbe and microbe-microbe metabolic interactions. NetCooperate determines these interaction indices from metabolic network topology, and can be used for small- or large-scale analyses. NetCooperate is provided as both a web-based tool and an open-source Python module; both are freely available online at http://elbo.gs.washington.edu/software_netcooperate.html.

Bioethical pluralism and complementarity.

PubMed

Grinnell, Frederick; Bishop, Jeffrey P; McCullough, Laurence B

2002-01-01

This essay presents complementarity as a novel feature of bioethical pluralism. First introduced by Neils Bohr in conjunction with quantum physics, complementarity in bioethics occurs when different perspectives account for equally important features of a situation but are mutually exclusive. Unlike conventional approaches to bioethical pluralism, which attempt in one fashion or another to isolate and choose between different perspectives, complementarity accepts all perspectives. As a result, complementarity results in a state of holistic, dynamic tension, rather than one that yields singular or final moral judgments.

CV-Muzar - The Virtual Community Environment that Uses Multiagent Systems for Formation of Groups

NASA Astrophysics Data System (ADS)

de Marchi, Ana Carolina Bertoletti; Moraes, Márcia Cristina

The purpose of this chapter is to present two agents' societies responsible for group formation (sub-communities) in CV-Muzar (Augusto Ruschi Zoobotanical Museum Virtual Community of the University of Passo Fundo). These societies are integrated to execute a data mining classification process. The first society is a static society that intends preprocessing data, investigating the information about groups in the CV-Muzar. The second society is a dynamical society that will make a classification process by analyzing the existing groups and look for participants that have common subjects in order to constitute a sub-community. The formation of sub-communities is a new functionality within the CV-Muzar that intends to bring the participants together according to two scopes: interest similarity and knowledge complementarities.

Open-quantum-systems approach to complementarity in neutral-kaon interferometry

NASA Astrophysics Data System (ADS)

de Souza, Gustavo; de Oliveira, J. G. G.; Varizi, Adalberto D.; Nogueira, Edson C.; Sampaio, Marcos D.

2016-12-01

In bipartite quantum systems, entanglement correlations between the parties exerts direct influence in the phenomenon of wave-particle duality. This effect has been quantitatively analyzed in the context of two qubits by Jakob and Bergou [Opt. Commun. 283, 827 (2010), 10.1016/j.optcom.2009.10.044]. Employing a description of the K -meson propagation in free space where its weak decay states are included as a second party, we study here this effect in the kaon-antikaon oscillations. We show that a new quantitative "triality" relation holds, similar to the one considered by Jakob and Bergou. In our case, it relates the distinguishability between the decay-product states corresponding to the distinct kaon propagation modes KS, KL, the amount of wave-like path interference between these states, and the amount of entanglement given by the reduced von Neumann entropy. The inequality can account for the complementarity between strangeness oscillations and lifetime information previously considered in the literature, therefore allowing one to see how it is affected by entanglement correlations. As we will discuss, it allows one to visualize clearly through the K0-K ¯0 oscillations the fundamental role of entanglement in quantum complementarity.

Birth-Order Complementarity and Marital Adjustment.

ERIC Educational Resources Information Center

Vos, Cornelia J. Vanderkooy; Hayden, Delbert J.

1985-01-01

Tested the influence of birth-order complementarity on marital adjustment among 327 married women using the Spanier Dyadic Adjustment Scale (1976). Birth-order complementarity was found to be unassociated with marital adjustment. (Author/BL)

Interactive effects of climate change and biodiversity loss on ecosystem functioning.

PubMed

Pires, Aliny P F; Srivastava, Diane S; Marino, Nicholas A C; MacDonald, A Andrew M; Figueiredo-Barros, Marcos Paulo; Farjalla, Vinicius F

2018-05-01

Climate change and biodiversity loss are expected to simultaneously affect ecosystems, however research on how each driver mediates the effect of the other has been limited in scope. The multiple stressor framework emphasizes non-additive effects, but biodiversity may also buffer the effects of climate change, and climate change may alter which mechanisms underlie biodiversity-function relationships. Here, we performed an experiment using tank bromeliad ecosystems to test the various ways that rainfall changes and litter diversity may jointly determine ecological processes. Litter diversity and rainfall changes interactively affected multiple functions, but how depends on the process measured. High litter diversity buffered the effects of altered rainfall on detritivore communities, evidence of insurance against impacts of climate change. Altered rainfall affected the mechanisms by which litter diversity influenced decomposition, reducing the importance of complementary attributes of species (complementarity effects), and resulting in an increasing dependence on the maintenance of specific species (dominance effects). Finally, altered rainfall conditions prevented litter diversity from fueling methanogenesis, because such changes in rainfall reduced microbial activity by 58%. Together, these results demonstrate that the effects of climate change and biodiversity loss on ecosystems cannot be understood in isolation and interactions between these stressors can be multifaceted. © 2018 by the Ecological Society of America.

Sampling and Complementarity Effects of Plant Diversity on Resource Use Increases the Invasion Resistance of Communities.

PubMed

Zhu, Dan H; Wang, Ping; Zhang, Wei Z; Yuan, Yue; Li, Bin; Wang, Jiang

2015-01-01

Although plant diversity is postulated to resist invasion, studies have not provided consistent results, most of which were ascribed to the influences of other covariate environmental factors. To explore the mechanisms by which plant diversity influences community invasibility, an experiment was conducted involving grassland sites varying in their species richness (one, two, four, eight, and sixteen species). Light interception efficiency and soil resources (total N, total P, and water content) were measured. The number of species, biomass, and the number of seedlings of the invading species decreased significantly with species richness. The presence of Patrinia scabiosaefolia Fisch. ex Trev. and Mosla dianthera (Buch.-Ham. ex Roxburgh) Maxim. significantly increased the resistance of the communities to invasion. A structural equation model showed that the richness of planted species had no direct and significant effect on invasion. Light interception efficiency had a negative effect on the invasion whereas soil water content had a positive effect. In monocultures, Antenoron filiforme (Thunb.) Rob. et Vaut. showed the highest light interception efficiency and P. scabiosaefolia recorded the lowest soil water content. With increased planted-species richness, a greater percentage of pots showed light use efficiency higher than that of A. filiforme and a lower soil water content than that in P. scabiosaefolia. The results of this study suggest that plant diversity confers resistance to invasion, which is mainly ascribed to the sampling effect of particular species and the complementarity effect among species on resources use.

Mood as Embodied Action: A Phenomenological Study of Interaction between Self and the Environment

ERIC Educational Resources Information Center

Manley, Dolores R.

2009-01-01

This phenomenological study explored the interaction between the affective phenomenon of mood (Davidson, et al., 2003) and embodied action (Varela, et al., 1993) experienced during interaction between self and the environment. Exploring the complementarity of mood and embodied action for organizations, teams, or individuals provided insightful…

The Psychometric Properties of the Short and Long Versions of the Coach-Athlete Relationship Questionnaire

ERIC Educational Resources Information Center

Yang, Sophie Xin; Jowett, Sophia

2013-01-01

The Coach-Athlete Relationship Questionnaire was developed to effectively measure affective, cognitive, and behavioral aspects, represented by the interpersonal constructs of closeness, commitment, and complementarity, of the quality of the relationship within the context of sport coaching. The current study sought to determine the internal…

Microbially Mediated Plant Salt Tolerance and Microbiome-based Solutions for Saline Agriculture.

PubMed

Qin, Yuan; Druzhinina, Irina S; Pan, Xueyu; Yuan, Zhilin

2016-11-15

Soil salinization adversely affects plant growth and has become one of the major limiting factors for crop productivity worldwide. The conventional approach, breeding salt-tolerant plant cultivars, has often failed to efficiently alleviate the situation. In contrast, the use of a diverse array of microorganisms harbored by plants has attracted increasing attention because of the remarkable beneficial effects of microorganisms on plants. Multiple advanced '-omics' technologies have enabled us to gain insights into the structure and function of plant-associated microbes. In this review, we first focus on microbe-mediated plant salt tolerance, in particular on the physiological and molecular mechanisms underlying root-microbe symbiosis. Unfortunately, when introducing such microbes as single strains to soils, they are often ineffective in improving plant growth and stress tolerance, largely due to competition with native soil microbial communities and limited colonization efficiency. Rapid progress in rhizosphere microbiome research has revived the belief that plants may benefit more from association with interacting, diverse microbial communities (microbiome) than from individual members in a community. Understanding how a microbiome assembles in the continuous compartments (endosphere, rhizoplane, and rhizosphere) will assist in predicting a subset of core or minimal microbiome and thus facilitate synthetic re-construction of microbial communities and their functional complementarity and synergistic effects. These developments will open a new avenue for capitalizing on the cultivable microbiome to strengthen plant salt tolerance and thus to refine agricultural practices and production under saline conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

Animal diversity and ecosystem functioning in dynamic food webs

NASA Astrophysics Data System (ADS)

Schneider, Florian D.; Brose, Ulrich; Rall, Björn C.; Guill, Christian

2016-10-01

Species diversity is changing globally and locally, but the complexity of ecological communities hampers a general understanding of the consequences of animal species loss on ecosystem functioning. High animal diversity increases complementarity of herbivores but also increases feeding rates within the consumer guild. Depending on the balance of these counteracting mechanisms, species-rich animal communities may put plants under top-down control or may release them from grazing pressure. Using a dynamic food-web model with body-mass constraints, we simulate ecosystem functions of 20,000 communities of varying animal diversity. We show that diverse animal communities accumulate more biomass and are more exploitative on plants, despite their higher rates of intra-guild predation. However, they do not reduce plant biomass because the communities are composed of larger, and thus energetically more efficient, plant and animal species. This plasticity of community body-size structure reconciles the debate on the consequences of animal species loss for primary productivity.

Functional identity and functional structure change through succession in a rocky intertidal marine herbivore assemblage.

PubMed

Aguilera, Moisés A; Navarrete, Sergio A

2012-01-01

Despite the great interest in characterizing the functional structure and resilience of functional groups in natural communities, few studies have examined in which way the roles and relationships of coexisting species change during community succession, a fundamental and natural process that follows the release of new resources in terrestrial and aquatic ecosystems. Variation in algal traits that characterize different phases and stages of community succession on rocky shores are likely to influence the magnitude, direction of effects, and the level of redundancy and complementarity in the diverse assemblage of herbivores. Two separate field experiments were conducted to quantify per capita and population effects and the functional relationship (i.e., redundancy or complementarity) of four herbivore species found in central Chile during early and late algal succession. The first experiment examined grazer effects on the colonization and establishment of early-succession algal species. The second experiment examined effects on the late-successional, dominant corticated alga Mazzaella laminarioides. Complementary laboratory experiments with all species and under natural environmental conditions allowed us to further characterize the collective effects of these species. We found that, during early community succession, all herbivore species had similar effects on the ephemeral algae, ulvoids, but only during the phase of colonization. Once these algae were established, only a subset of the species was able to control their abundance. During late succession, only the keyhole limpet Fissurella crassa could control corticated Mazzaella. The functional relationships among these species changed dramatically from redundant effects on ephemeral algae during early colonization, to a more complementary role on established early-successional algae, to a dominant (i.e., keystone) effect on late succession. This study highlights that functional relationship within consumer assemblages can vary at different phases and times of community succession. Differentiation in herbivore roles emphasizes the need to evaluate consumer's impacts through different times of community succession, and through experimental manipulations to make even broad predictions about the resilience or vulnerability of diverse intertidal assemblages to human disturbances.

Household adoption of energy and water-efficient appliances: An analysis of attitudes, labelling and complementary green behaviours in selected OECD countries.

PubMed

Dieu-Hang, To; Grafton, R Quentin; Martínez-Espiñeira, Roberto; Garcia-Valiñas, Maria

2017-07-15

Using a household-based data set of more than 12,000 households from 11 OECD countries, we analyse the factors underlying the decision by households to adopt energy-efficient and water-efficient equipment. We evaluate the roles of both attitudes and labelling schemes on the adoption of energy and water-efficient equipment, and also the interaction and complementarity between energy and water conservation behaviours. Our findings show: one, 'green' social norms and favourable attitudes towards the environment are associated with an increased likelihood of households' adoption of energy and water-efficient appliances; two, households' purchase decisions are positively affected by their awareness, understanding, and trust of labelling schemes; and three, there is evidence of complementarity between energy conservation and water conservation behaviours. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interpersonal complementarity in the mental health intake: a mixed-methods study.

PubMed

Rosen, Daniel C; Miller, Alisa B; Nakash, Ora; Halpern, Lucila; Halperin, Lucila; Alegría, Margarita

2012-04-01

The study examined which socio-demographic differences between clients and providers influenced interpersonal complementarity during an initial intake session; that is, behaviors that facilitate harmonious interactions between client and provider. Complementarity was assessed using blinded ratings of 114 videotaped intake sessions by trained observers. Hierarchical linear models were used to examine how match between client and provider in race/ethnicity, sex, and age were associated with levels of complementarity. A qualitative analysis investigated potential mechanisms that accounted for overall complementarity beyond match by examining client-provider dyads in the top and bottom quartiles of the complementarity measure. Results indicated significant interactions between client's race/ethnicity (Black) and provider's race/ethnicity (Latino) (p = .036) and client's age and provider's age (p = .044) on the Affiliation axis. The qualitative investigation revealed that client-provider interactions in the upper quartile of complementarity were characterized by consistent descriptions between the client and provider of concerns and expectations as well as depictions of what was important during the meeting. Results suggest that differences in social identities, although important, may be overcome by interpersonal variables early in the therapeutic relationship. Implications for both clinical practice and future research are discussed, as are factors relevant to working across cultures.

Complementarity and Area-Efficiency in the Prioritization of the Global Protected Area Network.

PubMed

Kullberg, Peter; Toivonen, Tuuli; Montesino Pouzols, Federico; Lehtomäki, Joona; Di Minin, Enrico; Moilanen, Atte

2015-01-01

Complementarity and cost-efficiency are widely used principles for protected area network design. Despite the wide use and robust theoretical underpinnings, their effects on the performance and patterns of priority areas are rarely studied in detail. Here we compare two approaches for identifying the management priority areas inside the global protected area network: 1) a scoring-based approach, used in recently published analysis and 2) a spatial prioritization method, which accounts for complementarity and area-efficiency. Using the same IUCN species distribution data the complementarity method found an equal-area set of priority areas with double the mean species ranges covered compared to the scoring-based approach. The complementarity set also had 72% more species with full ranges covered, and lacked any coverage only for half of the species compared to the scoring approach. Protected areas in our complementarity-based solution were on average smaller and geographically more scattered. The large difference between the two solutions highlights the need for critical thinking about the selected prioritization method. According to our analysis, accounting for complementarity and area-efficiency can lead to considerable improvements when setting management priorities for the global protected area network.

Bacterial biodiversity-ecosystem functioning relations are modified by environmental complexity.

PubMed

Langenheder, Silke; Bulling, Mark T; Solan, Martin; Prosser, James I

2010-05-26

With the recognition that environmental change resulting from anthropogenic activities is causing a global decline in biodiversity, much attention has been devoted to understanding how changes in biodiversity may alter levels of ecosystem functioning. Although environmental complexity has long been recognised as a major driving force in evolutionary processes, it has only recently been incorporated into biodiversity-ecosystem functioning investigations. Environmental complexity is expected to strengthen the positive effect of species richness on ecosystem functioning, mainly because it leads to stronger complementarity effects, such as resource partitioning and facilitative interactions among species when the number of available resource increases. Here we implemented an experiment to test the combined effect of species richness and environmental complexity, more specifically, resource richness on ecosystem functioning over time. We show, using all possible combinations of species within a bacterial community consisting of six species, and all possible combinations of three substrates, that diversity-functioning (metabolic activity) relationships change over time from linear to saturated. This was probably caused by a combination of limited complementarity effects and negative interactions among competing species as the experiment progressed. Even though species richness and resource richness both enhanced ecosystem functioning, they did so independently from each other. Instead there were complex interactions between particular species and substrate combinations. Our study shows clearly that both species richness and environmental complexity increase ecosystem functioning. The finding that there was no direct interaction between these two factors, but that instead rather complex interactions between combinations of certain species and resources underlie positive biodiversity ecosystem functioning relationships, suggests that detailed knowledge of how individual species interact with complex natural environments will be required in order to make reliable predictions about how altered levels of biodiversity will most likely affect ecosystem functioning.

Bacterial Biodiversity-Ecosystem Functioning Relations Are Modified by Environmental Complexity

PubMed Central

Langenheder, Silke; Bulling, Mark T.; Solan, Martin; Prosser, James I.

2010-01-01

Background With the recognition that environmental change resulting from anthropogenic activities is causing a global decline in biodiversity, much attention has been devoted to understanding how changes in biodiversity may alter levels of ecosystem functioning. Although environmental complexity has long been recognised as a major driving force in evolutionary processes, it has only recently been incorporated into biodiversity-ecosystem functioning investigations. Environmental complexity is expected to strengthen the positive effect of species richness on ecosystem functioning, mainly because it leads to stronger complementarity effects, such as resource partitioning and facilitative interactions among species when the number of available resource increases. Methodology/Principal Findings Here we implemented an experiment to test the combined effect of species richness and environmental complexity, more specifically, resource richness on ecosystem functioning over time. We show, using all possible combinations of species within a bacterial community consisting of six species, and all possible combinations of three substrates, that diversity-functioning (metabolic activity) relationships change over time from linear to saturated. This was probably caused by a combination of limited complementarity effects and negative interactions among competing species as the experiment progressed. Even though species richness and resource richness both enhanced ecosystem functioning, they did so independently from each other. Instead there were complex interactions between particular species and substrate combinations. Conclusions/Significance Our study shows clearly that both species richness and environmental complexity increase ecosystem functioning. The finding that there was no direct interaction between these two factors, but that instead rather complex interactions between combinations of certain species and resources underlie positive biodiversity ecosystem functioning relationships, suggests that detailed knowledge of how individual species interact with complex natural environments will be required in order to make reliable predictions about how altered levels of biodiversity will most likely affect ecosystem functioning. PMID:20520808

Reducing Insecurity in Africa: Roles and Responsibilities of the U.S. Military, U.S. Government and Non-Governmental Communities

DTIC Science & Technology

2012-04-01

government, how to create programs that build on the complementarities between various actors (within and outside the government), and what...the participants aired their opinions and listened to each others’ perspectives. Even when they disagreed, learning why disagreements surfaced helped...many African countries the security sector itself—those actors and institutions with the central charge of providing defense and security—have too

Interpersonal Complementarity in the Mental Health Intake: A Mixed-Methods Study

ERIC Educational Resources Information Center

Rosen, Daniel C.; Miller, Alisa B.; Nakash, Ora; Halperin, Lucila; Alegria, Margarita

2012-01-01

The study examined which socio-demographic differences between clients and providers influenced interpersonal complementarity during an initial intake session; that is, behaviors that facilitate harmonious interactions between client and provider. Complementarity was assessed using blinded ratings of 114 videotaped intake sessions by trained…

Electrostatic complementarity at protein/protein interfaces.

PubMed

McCoy, A J; Chandana Epa, V; Colman, P M

1997-05-02

Calculation of the electrostatic potential of protein-protein complexes has led to the general assertion that protein-protein interfaces display "charge complementarity" and "electrostatic complementarity". In this study, quantitative measures for these two terms are developed and used to investigate protein-protein interfaces in a rigorous manner. Charge complementarity (CC) was defined using the correlation of charges on nearest neighbour atoms at the interface. All 12 protein-protein interfaces studied had insignificantly small CC values. Therefore, the term charge complementarity is not appropriate for the description of protein-protein interfaces when used in the sense measured by CC. Electrostatic complementarity (EC) was defined using the correlation of surface electrostatic potential at protein-protein interfaces. All twelve protein-protein interfaces studied had significant EC values, and thus the assertion that protein-protein association involves surfaces with complementary electrostatic potential was substantially confirmed. The term electrostatic complementarity can therefore be used to describe protein-protein interfaces when used in the sense measured by EC. Taken together, the results for CC and EC demonstrate the relevance of the long-range effects of charges, as described by the electrostatic potential at the binding interface. The EC value did not partition the complexes by type such as antigen-antibody and proteinase-inhibitor, as measures of the geometrical complementarity at protein-protein interfaces have done. The EC value was also not directly related to the number of salt bridges in the interface, and neutralisation of these salt bridges showed that other charges also contributed significantly to electrostatic complementarity and electrostatic interactions between the proteins. Electrostatic complementarity as defined by EC was extended to investigate the electrostatic similarity at the surface of influenza virus neuraminidase where the epitopes of two monoclonal antibodies, NC10 and NC41, overlap. Although NC10 and NC41 both have quite high values of EC for their interaction with neuraminidase, the similarity in electrostatic potential generated by the two on the overlapping region of the epitopes is insignificant. Thus, it is possible for two antibodies to recognise the electrostatic surface of a protein in dissimilar ways.

Comment on measuring the tt forward-backward asymmetry at ATLAS and CMS

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

Arguin, Jean-Francois; Ligeti, Zoltan; Freytsis, Marat

2011-10-01

We suggest a new possibility for ATLAS and CMS to explore the tt forward-backward asymmetry measured at the Tevatron, by attempting to reconstruct tt events, with one of the tops decaying semileptonically in the central region (|{eta}|<2.5) and the other decaying hadronically in the forward region (|{eta}|>2.5). For several models which give comparable Tevatron signals, we study the charge asymmetry at the LHC as a function of cuts on |{eta}| and on the tt invariant mass, m{sub tt}. We show that there is an interesting complementarity between cuts on |{eta}| and m{sub tt} to suppress the dominant and symmetric gg{yields}ttmore » rate, and different combinations of cuts enhance the distinguishing power between models. This complementarity is likely to hold in other new physics scenarios as well, which affect the tt cross section, so it motivates extending tt reconstruction to higher |{eta}|.« less

Computational sequence analysis of predicted long dsRNA transcriptomes of major crops reveals sequence complementarity with human genes.

PubMed

Jensen, Peter D; Zhang, Yuanji; Wiggins, B Elizabeth; Petrick, Jay S; Zhu, Jin; Kerstetter, Randall A; Heck, Gregory R; Ivashuta, Sergey I

2013-01-01

Long double-stranded RNAs (long dsRNAs) are precursors for the effector molecules of sequence-specific RNA-based gene silencing in eukaryotes. Plant cells can contain numerous endogenous long dsRNAs. This study demonstrates that such endogenous long dsRNAs in plants have sequence complementarity to human genes. Many of these complementary long dsRNAs have perfect sequence complementarity of at least 21 nucleotides to human genes; enough complementarity to potentially trigger gene silencing in targeted human cells if delivered in functional form. However, the number and diversity of long dsRNA molecules in plant tissue from crops such as lettuce, tomato, corn, soy and rice with complementarity to human genes that have a long history of safe consumption supports a conclusion that long dsRNAs do not present a significant dietary risk.

Risk, rationality, and community: Psychology, ethnography, and transactions in the risk management process

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

Cantor, R.; Schoepfle, M.

Communities at risk are confronted by an increasingly complex array of opportunities and need for involvement in decisions affecting them. Policy analysis often demands from researchers insights into the complicated process of how best to account for community involvement in decision making. Often, this requires additional understanding of how decisions are made by community members. Researchers trying to capture the important features of decision making will necessarily make assumptions regarding the rationality underlying the decision process. Two implicit and often incompatible sets of research assumptions about decision processes have emerged: outcome rationality and process rationality. Using outcome rationality, the principalmore » goal of risk research often is to predict how people will react to risk regardless of what they say they would do. Using process rationality, the research goal is to determine how people perceive the risks to which they are exposed and how perceptions actually influence responses. The former approach is associated with research in risk communication, conducted by economists and cognitive psychologists; the latter approach is associated with the field of risk negotiation and acceptance, conducted by anthropologists, some sociologists, and planners. This article describes (1) the difference between the assumptions behind outcome and process rationality regarding decision making and the problems resulting from these differences; (2) the promise and limitations of both sets of assumptions; (3) the potential contributions from cognitive psychology, cognitive ethnography, and the theory of transaction costs in reconciling the differences in assumptions and making them more complementary; and (4) the implications of such complementarity.« less

The fully actuated traffic control problem solved by global optimization and complementarity

NASA Astrophysics Data System (ADS)

Ribeiro, Isabel M.; de Lurdes de Oliveira Simões, Maria

2016-02-01

Global optimization and complementarity are used to determine the signal timing for fully actuated traffic control, regarding effective green and red times on each cycle. The average values of these parameters can be used to estimate the control delay of vehicles. In this article, a two-phase queuing system for a signalized intersection is outlined, based on the principle of minimization of the total waiting time for the vehicles. The underlying model results in a linear program with linear complementarity constraints, solved by a sequential complementarity algorithm. Departure rates of vehicles during green and yellow periods were treated as deterministic, while arrival rates of vehicles were assumed to follow a Poisson distribution. Several traffic scenarios were created and solved. The numerical results reveal that it is possible to use global optimization and complementarity over a reasonable number of cycles and determine with efficiency effective green and red times for a signalized intersection.

[Non-EC workers in Italy: an overview of the literature and an attempt to test various hypotheses].

PubMed

Strozza, S

1995-09-01

"The essay presents an overview of the interpretations offered in scientific literature about causes and effects of non-EC [European Community] immigrants' integration into the Italian labor market....The essay uses the aggregate data of [the] Labor Ministry integrated by local surveys to answer some questions...[concerning] the link between sex, Italian region, place of origin and sector of activity...and the complementarity or competition with [the] Italian labor force." (SUMMARY IN ENG AND FRE) excerpt

Complementarity As Generative Principle: A Thought Pattern for Aesthetic Appreciations and Cognitive Appraisals in General

PubMed Central

Bao, Yan; von Stosch, Alexandra; Park, Mona; Pöppel, Ernst

2017-01-01

In experimental aesthetics the relationship between the arts and cognitive neuroscience has gained particular interest in recent years. But has cognitive neuroscience indeed something to offer when studying the arts? Here we present a theoretical frame within which the concept of complementarity as a generative or creative principle is proposed; neurocognitive processes are characterized by the duality of complementary activities like bottom-up and top-down control, or logistical functions like temporal control and content functions like perceptions in the neural machinery. On that basis a thought pattern is suggested for aesthetic appreciations and cognitive appraisals in general. This thought pattern is deeply rooted in the history of philosophy and art theory since antiquity; and complementarity also characterizes neural operations as basis for cognitive processes. We then discuss some challenges one is confronted with in experimental aesthetics; in our opinion, one serious problem is the lack of a taxonomy of functions in psychology and neuroscience which is generally accepted. This deficit makes it next to impossible to develop acceptable models which are similar to what has to be modeled. Another problem is the severe language bias in this field of research as knowledge gained in many languages over the ages remains inaccessible to most scientists. Thus, an inspection of research results or theoretical concepts is necessarily too narrow. In spite of these limitations we provide a selective summary of some results and viewpoints with a focus on visual art and its appreciation. It is described how questions of art and aesthetic appreciations using behavioral methods and in particular brain-imaging techniques are analyzed and evaluated focusing on such issues like the representation of artwork or affective experiences. Finally, we emphasize complementarity as a generative principle on a practical level when artists and scientists work directly together which can lead to new insights and broader perspectives on both sides. PMID:28536548

Complementarity As Generative Principle: A Thought Pattern for Aesthetic Appreciations and Cognitive Appraisals in General.

PubMed

Bao, Yan; von Stosch, Alexandra; Park, Mona; Pöppel, Ernst

2017-01-01

In experimental aesthetics the relationship between the arts and cognitive neuroscience has gained particular interest in recent years. But has cognitive neuroscience indeed something to offer when studying the arts? Here we present a theoretical frame within which the concept of complementarity as a generative or creative principle is proposed; neurocognitive processes are characterized by the duality of complementary activities like bottom-up and top-down control, or logistical functions like temporal control and content functions like perceptions in the neural machinery. On that basis a thought pattern is suggested for aesthetic appreciations and cognitive appraisals in general. This thought pattern is deeply rooted in the history of philosophy and art theory since antiquity; and complementarity also characterizes neural operations as basis for cognitive processes. We then discuss some challenges one is confronted with in experimental aesthetics; in our opinion, one serious problem is the lack of a taxonomy of functions in psychology and neuroscience which is generally accepted. This deficit makes it next to impossible to develop acceptable models which are similar to what has to be modeled. Another problem is the severe language bias in this field of research as knowledge gained in many languages over the ages remains inaccessible to most scientists. Thus, an inspection of research results or theoretical concepts is necessarily too narrow. In spite of these limitations we provide a selective summary of some results and viewpoints with a focus on visual art and its appreciation. It is described how questions of art and aesthetic appreciations using behavioral methods and in particular brain-imaging techniques are analyzed and evaluated focusing on such issues like the representation of artwork or affective experiences. Finally, we emphasize complementarity as a generative principle on a practical level when artists and scientists work directly together which can lead to new insights and broader perspectives on both sides.

Community-weighted mean of leaf traits and divergence of wood traits predict aboveground biomass in secondary subtropical forests.

PubMed

Ali, Arshad; Yan, En-Rong; Chang, Scott X; Cheng, Jun-Yang; Liu, Xiang-Yu

2017-01-01

Subtropical forests are globally important in providing ecological goods and services, but it is not clear whether functional diversity and composition can predict aboveground biomass in such forests. We hypothesized that high aboveground biomass is associated with high functional divergence (FDvar, i.e., niche complementarity) and community-weighted mean (CWM, i.e., mass ratio; communities dominated by a single plant strategy) of trait values. Structural equation modeling was employed to determine the direct and indirect effects of stand age and the residual effects of CWM and FDvar on aboveground biomass across 31 plots in secondary forests in subtropical China. The CWM model accounted for 78, 20, 6 and 2% of the variation in aboveground biomass, nitrogen concentration in young leaf, plant height and specific leaf area of young leaf, respectively. The FDvar model explained 74, 13, 7 and 0% of the variation in aboveground biomass, plant height, twig wood density and nitrogen concentration in young leaf, respectively. The variation in aboveground biomass, CWM of leaf nitrogen concentration and specific leaf area, and FDvar of plant height, twig wood density and nitrogen concentration in young leaf explained by the joint model was 86, 20, 13, 7, 2 and 0%, respectively. Stand age had a strong positive direct effect but low indirect positive effects on aboveground biomass. Aboveground biomass was negatively related to CWM of nitrogen concentration in young leaf, but positively related to CWM of specific leaf area of young leaf and plant height, and FDvar of plant height, twig wood density and nitrogen concentration in young leaf. Leaf and wood economics spectra are decoupled in regulating the functionality of forests, communities with diverse species but high nitrogen conservative and light acquisitive strategies result in high aboveground biomass, and hence, supporting both the mass ratio and niche complementarity hypotheses in secondary subtropical forests. Copyright © 2016 Elsevier B.V. All rights reserved.

Complementarity effects on tree growth are contingent on tree size and climatic conditions across Europe

PubMed Central

Madrigal-González, Jaime; Ruiz-Benito, Paloma; Ratcliffe, Sophia; Calatayud, Joaquín; Kändler, Gerald; Lehtonen, Aleksi; Dahlgren, Jonas; Wirth, Christian; Zavala, Miguel A.

2016-01-01

Neglecting tree size and stand structure dynamics might bias the interpretation of the diversity-productivity relationship in forests. Here we show evidence that complementarity is contingent on tree size across large-scale climatic gradients in Europe. We compiled growth data of the 14 most dominant tree species in 32,628 permanent plots covering boreal, temperate and Mediterranean forest biomes. Niche complementarity is expected to result in significant growth increments of trees surrounded by a larger proportion of functionally dissimilar neighbours. Functional dissimilarity at the tree level was assessed using four functional types: i.e. broad-leaved deciduous, broad-leaved evergreen, needle-leaved deciduous and needle-leaved evergreen. Using Linear Mixed Models we show that, complementarity effects depend on tree size along an energy availability gradient across Europe. Specifically: (i) complementarity effects at low and intermediate positions of the gradient (coldest-temperate areas) were stronger for small than for large trees; (ii) in contrast, at the upper end of the gradient (warmer regions), complementarity is more widespread in larger than smaller trees, which in turn showed negative growth responses to increased functional dissimilarity. Our findings suggest that the outcome of species mixing on stand productivity might critically depend on individual size distribution structure along gradients of environmental variation. PMID:27571971

Shape Complementarity of Protein-Protein Complexes at Multiple Resolutions

PubMed Central

Zhang, Qing; Sanner, Michel; Olson, Arthur J.

2010-01-01

Biological complexes typically exhibit intermolecular interfaces of high shape complementarity. Many computational docking approaches use this surface complementarity as a guide in the search for predicting the structures of protein-protein complexes. Proteins often undergo conformational changes in order to create a highly complementary interface when associating. These conformational changes are a major cause of failure for automated docking procedures when predicting binding modes between proteins using their unbound conformations. Low resolution surfaces in which high frequency geometric details are omitted have been used to address this problem. These smoothed, or blurred, surfaces are expected to minimize the differences between free and bound structures, especially those that are due to side chain conformations or small backbone deviations. In spite of the fact that this approach has been used in many docking protocols, there has yet to be a systematic study of the effects of such surface smoothing on the shape complementarity of the resulting interfaces. Here we investigate this question by computing shape complementarity of a set of 66 protein-protein complexes represented by multi-resolution blurred surfaces. Complexed and unbound structures are available for these protein-protein complexes. They are a subset of complexes from a non-redundant docking benchmark selected for rigidity (i.e. the proteins undergo limited conformational changes between their bound and unbound states). In this work we construct the surfaces by isocontouring a density map obtained by accumulating the densities of Gaussian functions placed at all atom centers of the molecule. The smoothness or resolution is specified by a Gaussian fall-off coefficient, termed “blobbyness”. Shape complementarity is quantified using a histogram of the shortest distances between two proteins' surface mesh vertices for both the crystallographic complexes and the complexes built using the protein structures in their unbound conformation. The histograms calculated for the bound complex structures demonstrate that medium resolution smoothing (blobbyness=−0.9) can reproduce about 88% of the shape complementarity of atomic resolution surfaces. Complexes formed from the free component structures show a partial loss of shape complementarity (more overlaps and gaps) with the atomic resolution surfaces. For surfaces smoothed to low resolution (blobbyness=−0.3), we find more consistency of shape complementarity between the complexed and free cases. To further reduce bad contacts without significantly impacting the good contacts we introduce another blurred surface, in which the Gaussian densities of flexible atoms are reduced. From these results we discuss the use of shape complementarity in protein-protein docking. PMID:18837463

Stability of neutrino parameters and self-complementarity relation with varying SUSY breaking scale

NASA Astrophysics Data System (ADS)

Singh, K. Sashikanta; Roy, Subhankar; Singh, N. Nimai

2018-03-01

The scale at which supersymmetry (SUSY) breaks (ms) is still unknown. The present article, following a top-down approach, endeavors to study the effect of varying ms on the radiative stability of the observational parameters associated with the neutrino mixing. These parameters get additional contributions in the minimal supersymmetric model (MSSM). A variation in ms will influence the bounds for which the Standard Model (SM) and MSSM work and hence, will account for the different radiative contributions received from both sectors, respectively, while running the renormalization group equations (RGE). The present work establishes the invariance of the self complementarity relation among the three mixing angles, θ13+θ12≈θ23 against the radiative evolution. A similar result concerning the mass ratio, m2:m1 is also found to be valid. In addition to varying ms, the work incorporates a range of different seesaw (SS) scales and tries to see how the latter affects the parameters.

Complementarity of genuine multipartite Bell nonlocality

NASA Astrophysics Data System (ADS)

Sami, Sasha; Chakrabarty, Indranil; Chaturvedi, Anubhav

2017-08-01

We introduce a feature of no-signaling (Bell) nonlocal theories: namely, when a system of multiple parties manifests genuine nonlocal correlation, then there cannot be arbitrarily high nonlocal correlation among any subset of the parties. We call this feature complementarity of genuine multipartite nonlocality. We use Svetlichny's criterion for genuine multipartite nonlocality and nonlocal games to derive the complementarity relations under no-signaling constraints. We find that the complementarity relations are tightened for the much stricter quantum constraints. We compare this notion with the well-known notion of monogamy of nonlocality. As a consequence, we obtain tighter nontrivial monogamy relations that take into account genuine multipartite nonlocality. Furthermore, we provide numerical evidence showcasing this feature using a bipartite measure and several other well-known tripartite measures of nonlocality.

Self-Complementarity within Proteins: Bridging the Gap between Binding and Folding

PubMed Central

Basu, Sankar; Bhattacharyya, Dhananjay; Banerjee, Rahul

2012-01-01

Complementarity, in terms of both shape and electrostatic potential, has been quantitatively estimated at protein-protein interfaces and used extensively to predict the specific geometry of association between interacting proteins. In this work, we attempted to place both binding and folding on a common conceptual platform based on complementarity. To that end, we estimated (for the first time to our knowledge) electrostatic complementarity (Em) for residues buried within proteins. Em measures the correlation of surface electrostatic potential at protein interiors. The results show fairly uniform and significant values for all amino acids. Interestingly, hydrophobic side chains also attain appreciable complementarity primarily due to the trajectory of the main chain. Previous work from our laboratory characterized the surface (or shape) complementarity (Sm) of interior residues, and both of these measures have now been combined to derive two scoring functions to identify the native fold amid a set of decoys. These scoring functions are somewhat similar to functions that discriminate among multiple solutions in a protein-protein docking exercise. The performances of both of these functions on state-of-the-art databases were comparable if not better than most currently available scoring functions. Thus, analogously to interfacial residues of protein chains associated (docked) with specific geometry, amino acids found in the native interior have to satisfy fairly stringent constraints in terms of both Sm and Em. The functions were also found to be useful for correctly identifying the same fold for two sequences with low sequence identity. Finally, inspired by the Ramachandran plot, we developed a plot of Sm versus Em (referred to as the complementarity plot) that identifies residues with suboptimal packing and electrostatics which appear to be correlated to coordinate errors. PMID:22713576

Self-complementarity within proteins: bridging the gap between binding and folding.

PubMed

Basu, Sankar; Bhattacharyya, Dhananjay; Banerjee, Rahul

2012-06-06

Complementarity, in terms of both shape and electrostatic potential, has been quantitatively estimated at protein-protein interfaces and used extensively to predict the specific geometry of association between interacting proteins. In this work, we attempted to place both binding and folding on a common conceptual platform based on complementarity. To that end, we estimated (for the first time to our knowledge) electrostatic complementarity (Em) for residues buried within proteins. Em measures the correlation of surface electrostatic potential at protein interiors. The results show fairly uniform and significant values for all amino acids. Interestingly, hydrophobic side chains also attain appreciable complementarity primarily due to the trajectory of the main chain. Previous work from our laboratory characterized the surface (or shape) complementarity (Sm) of interior residues, and both of these measures have now been combined to derive two scoring functions to identify the native fold amid a set of decoys. These scoring functions are somewhat similar to functions that discriminate among multiple solutions in a protein-protein docking exercise. The performances of both of these functions on state-of-the-art databases were comparable if not better than most currently available scoring functions. Thus, analogously to interfacial residues of protein chains associated (docked) with specific geometry, amino acids found in the native interior have to satisfy fairly stringent constraints in terms of both Sm and Em. The functions were also found to be useful for correctly identifying the same fold for two sequences with low sequence identity. Finally, inspired by the Ramachandran plot, we developed a plot of Sm versus Em (referred to as the complementarity plot) that identifies residues with suboptimal packing and electrostatics which appear to be correlated to coordinate errors. Copyright © 2012 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Private algebras in quantum information and infinite-dimensional complementarity

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

Crann, Jason, E-mail: jason-crann@carleton.ca; Laboratoire de Mathématiques Paul Painlevé–UMR CNRS 8524, UFR de Mathématiques, Université Lille 1–Sciences et Technologies, 59655 Villeneuve d’Ascq Cédex; Kribs, David W., E-mail: dkribs@uoguelph.ca

We introduce a generalized framework for private quantum codes using von Neumann algebras and the structure of commutants. This leads naturally to a more general notion of complementary channel, which we use to establish a generalized complementarity theorem between private and correctable subalgebras that applies to both the finite and infinite-dimensional settings. Linear bosonic channels are considered and specific examples of Gaussian quantum channels are given to illustrate the new framework together with the complementarity theorem.

Generalized uncertainty principle: implications for black hole complementarity

NASA Astrophysics Data System (ADS)

Chen, Pisin; Ong, Yen Chin; Yeom, Dong-han

2014-12-01

At the heart of the black hole information loss paradox and the firewall controversy lies the conflict between quantum mechanics and general relativity. Much has been said about quantum corrections to general relativity, but much less in the opposite direction. It is therefore crucial to examine possible corrections to quantum mechanics due to gravity. Indeed, the Heisenberg Uncertainty Principle is one profound feature of quantum mechanics, which nevertheless may receive correction when gravitational effects become important. Such generalized uncertainty principle [GUP] has been motivated from not only quite general considerations of quantum mechanics and gravity, but also string theoretic arguments. We examine the role of GUP in the context of black hole complementarity. We find that while complementarity can be violated by large N rescaling if one assumes only the Heisenberg's Uncertainty Principle, the application of GUP may save complementarity, but only if certain N -dependence is also assumed. This raises two important questions beyond the scope of this work, i.e., whether GUP really has the proposed form of N -dependence, and whether black hole complementarity is indeed correct.

Getting the full picture: Assessing the complementarity of citizen science and agency monitoring data.

PubMed

Hadj-Hammou, Jeneen; Loiselle, Steven; Ophof, Daniel; Thornhill, Ian

2017-01-01

While the role of citizen science in engaging the public and providing large-scale datasets has been demonstrated, the nature of and potential for this science to supplement environmental monitoring efforts by government agencies has not yet been fully explored. To this end, the present study investigates the complementarity of a citizen science programme to agency monitoring of water quality. The Environment Agency (EA) is the governmental public body responsible for, among other duties, managing and monitoring water quality and water resources in England. FreshWater Watch (FWW) is a global citizen science project that supports community monitoring of freshwater quality. FWW and EA data were assessed for their spatio-temporal complementarity by comparing the geographical and seasonal coverage of nitrate (N-NO3) sampling across the River Thames catchment by the respective campaigns between spring 2013 and winter 2015. The analysis reveals that FWW citizen science-collected data complements EA data by filling in both gaps in the spatial and temporal coverage as well as gaps in waterbody type and size. In addition, partial spatio-temporal overlap in sampling efforts by the two actors is discovered, but EA sampling is found to be more consistent than FWW sampling. Statistical analyses indicate that regardless of broader geographical overlap in sampling effort, FWW sampling sites are associated with a lower stream order and water bodies of smaller surface areas than EA sampling sites. FWW also samples more still-water body sites than the EA. As a possible result of such differences in sampling tendencies, nitrate concentrations, a measure of water quality, are lower for FWW sites than EA sites. These findings strongly indicate that citizen science has clear potential to complement agency monitoring efforts by generating information on freshwater ecosystems that would otherwise be under reported.

Getting the full picture: Assessing the complementarity of citizen science and agency monitoring data

PubMed Central

Loiselle, Steven; Ophof, Daniel; Thornhill, Ian

2017-01-01

While the role of citizen science in engaging the public and providing large-scale datasets has been demonstrated, the nature of and potential for this science to supplement environmental monitoring efforts by government agencies has not yet been fully explored. To this end, the present study investigates the complementarity of a citizen science programme to agency monitoring of water quality. The Environment Agency (EA) is the governmental public body responsible for, among other duties, managing and monitoring water quality and water resources in England. FreshWater Watch (FWW) is a global citizen science project that supports community monitoring of freshwater quality. FWW and EA data were assessed for their spatio-temporal complementarity by comparing the geographical and seasonal coverage of nitrate (N-NO3) sampling across the River Thames catchment by the respective campaigns between spring 2013 and winter 2015. The analysis reveals that FWW citizen science-collected data complements EA data by filling in both gaps in the spatial and temporal coverage as well as gaps in waterbody type and size. In addition, partial spatio-temporal overlap in sampling efforts by the two actors is discovered, but EA sampling is found to be more consistent than FWW sampling. Statistical analyses indicate that regardless of broader geographical overlap in sampling effort, FWW sampling sites are associated with a lower stream order and water bodies of smaller surface areas than EA sampling sites. FWW also samples more still-water body sites than the EA. As a possible result of such differences in sampling tendencies, nitrate concentrations, a measure of water quality, are lower for FWW sites than EA sites. These findings strongly indicate that citizen science has clear potential to complement agency monitoring efforts by generating information on freshwater ecosystems that would otherwise be under reported. PMID:29211752

Functional diversity of fish communities in two tropical estuaries subjected to anthropogenic disturbance.

PubMed

Dolbeth, M; Vendel, A L; Pessanha, A; Patrício, J

2016-11-15

The functional diversity of fish communities was studied along the salinity gradient of two estuaries in Northeast Brazil subjected to different anthropogenic pressures, to gain a better understanding of the response of fish communities to disturbance. We evaluated functional complementarity indices, redundancy and analysed functional composition through functional groups based on combinations of different traits. The fish communities in both estuaries share similar functions performed by few functional groups. The upstream areas had generally lower taxonomic, functional diversity and lower redundancy, suggesting greater vulnerability to impacts caused by human activities. Biomass was slightly more evenly distributed among functional groups in the less disturbed estuary, but total biomass and redundancy were lower in comparison to the urbanized estuary. The present findings lend strength to the notion that the less disturbed estuary may be more susceptible to anthropogenic impacts, underscoring the need for more effective conservation measures directed at this estuary. Copyright © 2016 Elsevier Ltd. All rights reserved.

Complementarity in false memory illusions.

PubMed

Brainerd, C J; Reyna, V F

2018-03-01

For some years, the DRM illusion has been the most widely studied form of false memory. The consensus theoretical interpretation is that the illusion is a reality reversal, in which certain new words (critical distractors) are remembered as though they are old list words rather than as what they are-new words that are similar to old ones. This reality-reversal interpretation is supported by compelling lines of evidence, but prior experiments are limited by the fact that their memory tests only asked whether test items were old. We removed that limitation by also asking whether test items were new-similar. This more comprehensive methodology revealed that list words and critical distractors are remembered quite differently. Memory for list words is compensatory: They are remembered as old at high rates and remembered as new-similar at very low rates. In contrast, memory for critical distractors is complementary: They are remembered as both old and new-similar at high rates, which means that the DRM procedure induces a complementarity illusion rather than a reality reversal. The conjoint recognition model explains complementarity as a function of three retrieval processes (semantic familiarity, target recollection, and context recollection), and it predicts that complementarity can be driven up or down by varying the mix of those processes. Our experiments generated data on that prediction and introduced a convenient statistic, the complementarity ratio, which measures (a) the level of complementarity in memory performance and (b) whether its direction is reality-consistent or reality-reversed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Model of early self-replication based on covalent complementarity for a copolymer of glycerate-3-phosphate and glycerol-3-phosphate

NASA Technical Reports Server (NTRS)

Weber, Arthur L.

1989-01-01

Glyceraldehyde-3-phosphate acts as the substrate in a model of early self-replication of a phosphodiester copolymer of glycerate-3-phosphate and glycerol-3-phosphate. This model of self-replication is based on covalent complementarity in which information transfer is mediated by a single covalent bond, in contrast to multiple weak interactions that establish complementarity in nucleic acid replication. This replication model is connected to contemporary biochemistry through its use of glyceraldehyde-3-phosphate, a central metabolite of glycolysis and photosynthesis.

Black hole complementarity with the generalized uncertainty principle in Gravity's Rainbow

NASA Astrophysics Data System (ADS)

Gim, Yongwan; Um, Hwajin; Kim, Wontae

2018-02-01

When gravitation is combined with quantum theory, the Heisenberg uncertainty principle could be extended to the generalized uncertainty principle accompanying a minimal length. To see how the generalized uncertainty principle works in the context of black hole complementarity, we calculate the required energy to duplicate information for the Schwarzschild black hole. It shows that the duplication of information is not allowed and black hole complementarity is still valid even assuming the generalized uncertainty principle. On the other hand, the generalized uncertainty principle with the minimal length could lead to a modification of the conventional dispersion relation in light of Gravity's Rainbow, where the minimal length is also invariant as well as the speed of light. Revisiting the gedanken experiment, we show that the no-cloning theorem for black hole complementarity can be made valid in the regime of Gravity's Rainbow on a certain combination of parameters.

Predicting Species-Resolved Macronutrient Acquisition during Succession in a Model Phototrophic Biofilm Using an Integrated ‘Omics Approach

PubMed Central

Lindemann, Stephen R.; Mobberley, Jennifer M.; Cole, Jessica K.; Markillie, L. M.; Taylor, Ronald C.; Huang, Eric; Chrisler, William B.; Wiley, H. S.; Lipton, Mary S.; Nelson, William C.; Fredrickson, James K.; Romine, Margaret F.

2017-01-01

The principles governing acquisition and interspecies exchange of nutrients in microbial communities and how those exchanges impact community productivity are poorly understood. Here, we examine energy and macronutrient acquisition in unicyanobacterial consortia for which species-resolved genome information exists for all members, allowing us to use multi-omic approaches to predict species’ abilities to acquire resources and examine expression of resource-acquisition genes during succession. Metabolic reconstruction indicated that a majority of heterotrophic community members lacked the genes required to directly acquire the inorganic nutrients provided in culture medium, suggesting high metabolic interdependency. The sole primary producer in consortium UCC-O, cyanobacterium Phormidium sp. OSCR, displayed declining expression of energy harvest, carbon fixation, and nitrate and sulfate reduction proteins but sharply increasing phosphate transporter expression over 28 days. Most heterotrophic members likewise exhibited signs of phosphorus starvation during succession. Though similar in their responses to phosphorus limitation, heterotrophs displayed species-specific expression of nitrogen acquisition genes. These results suggest niche partitioning around nitrogen sources may structure the community when organisms directly compete for limited phosphate. Such niche complementarity around nitrogen sources may increase community diversity and productivity in phosphate-limited phototrophic communities. PMID:28659875

The role of species traits in mediating functional recovery during matrix restoration.

PubMed

Barnes, Andrew D; Emberson, Rowan M; Krell, Frank-Thorsten; Didham, Raphael K

2014-01-01

Reversing anthropogenic impacts on habitat structure is frequently successful through restoration, but the mechanisms linking habitat change, community reassembly and recovery of ecosystem functioning remain unknown. We test for the influence of edge effects and matrix habitat restoration on the reassembly of dung beetle communities and consequent recovery of dung removal rates across tropical forest edges. Using path modelling, we disentangle the relative importance of community-weighted trait means and functional trait dispersion from total biomass effects on rates of dung removal. Community trait composition and biomass of dung beetle communities responded divergently to edge effects and matrix habitat restoration, yielding opposing effects on dung removal. However, functional dispersion--used in this study as a measure of niche complementarity--did not explain a significant amount of variation in dung removal rates across habitat edges. Instead, we demonstrate that the path to functional recovery of these altered ecosystems depends on the trait-mean composition of reassembling communities, over and above purely biomass-dependent processes that would be expected under neutral theory. These results suggest that any ability to manage functional recovery of ecosystems during habitat restoration will demand knowledge of species' roles in ecosystem processes.

Complementarity and Compensation: Bridging the Gap between Writing and Design.

ERIC Educational Resources Information Center

Killingsworth, M. Jimmie; Sanders, Scott P.

1990-01-01

Outlines two rhetorical principles for producing iconic-mosaic texts--the principle of complementarity and the principle of compensation. Shows how these principles can be applied to practical problems in coordinating the writing and design processes in student projects. (RS)

Educational Finance Policy: A Search for Complementarities.

ERIC Educational Resources Information Center

Geske, Terry G.

1983-01-01

An overview of recent state level policy developments and policy analysis research as related to equity and efficiency objectives in public school finance is presented. Emphasis is placed on identifying complementarities, rather than the tradeoffs, between equity and efficiency criteria. (Author/LC)

Intron self-complementarity enforces exon inclusion in a yeast pre-mRNA

PubMed Central

Howe, Kenneth James; Ares, Manuel

1997-01-01

Skipping of internal exons during removal of introns from pre-mRNA must be avoided for proper expression of most eukaryotic genes. Despite significant understanding of the mechanics of intron removal, mechanisms that ensure inclusion of internal exons in multi-intron pre-mRNAs remain mysterious. Using a natural two-intron yeast gene, we have identified distinct RNA–RNA complementarities within each intron that prevent exon skipping and ensure inclusion of internal exons. We show that these complementarities are positioned to act as intron identity elements, bringing together only the appropriate 5′ splice sites and branchpoints. Destroying either intron self-complementarity allows exon skipping to occur, and restoring the complementarity using compensatory mutations rescues exon inclusion, indicating that the elements act through formation of RNA secondary structure. Introducing new pairing potential between regions near the 5′ splice site of intron 1 and the branchpoint of intron 2 dramatically enhances exon skipping. Similar elements identified in single intron yeast genes contribute to splicing efficiency. Our results illustrate how intron secondary structure serves to coordinate splice site pairing and enforce exon inclusion. We suggest that similar elements in vertebrate genes could assist in the splicing of very large introns and in the evolution of alternative splicing. PMID:9356473

Beyond Contagion: Reality Mining Reveals Complex Patterns of Social Influence.

PubMed

Alshamsi, Aamena; Pianesi, Fabio; Lepri, Bruno; Pentland, Alex; Rahwan, Iyad

2015-01-01

Contagion, a concept from epidemiology, has long been used to characterize social influence on people's behavior and affective (emotional) states. While it has revealed many useful insights, it is not clear whether the contagion metaphor is sufficient to fully characterize the complex dynamics of psychological states in a social context. Using wearable sensors that capture daily face-to-face interaction, combined with three daily experience sampling surveys, we collected the most comprehensive data set of personality and emotion dynamics of an entire community of work. From this high-resolution data about actual (rather than self-reported) face-to-face interaction, a complex picture emerges where contagion (that can be seen as adaptation of behavioral responses to the behavior of other people) cannot fully capture the dynamics of transitory states. We found that social influence has two opposing effects on states: adaptation effects that go beyond mere contagion, and complementarity effects whereby individuals' behaviors tend to complement the behaviors of others. Surprisingly, these effects can exhibit completely different directions depending on the stable personality or emotional dispositions (stable traits) of target individuals. Our findings provide a foundation for richer models of social dynamics, and have implications on organizational engineering and workplace well-being.

Furthering the quality agenda in Aboriginal community controlled health services: understanding the relationship between accreditation, continuous quality improvement and national key performance indicator reporting.

PubMed

Sibthorpe, Beverly; Gardner, Karen; McAullay, Daniel

2016-01-01

A rapidly expanding interest in quality in the Aboriginal-community-controlled health sector has led to widespread uptake of accreditation using more than one set of standards, a proliferation of continuous quality improvement programs and the introduction of key performance indicators. As yet, there has been no overarching logic that shows how they relate to each other, with consequent confusion within and outside the sector. We map the three approaches to the Framework for Performance Assessment in Primary Health Care, demonstrating their key differences and complementarity. There needs to be greater attention in both policy and practice to the purposes and alignment of the three approaches if they are to embed a system-wide focus that supports quality improvement at the service level.

Functional traits explain ecosystem function through opposing mechanisms.

PubMed

Cadotte, Marc W

2017-08-01

The ability to explain why multispecies assemblages produce greater biomass compared to monocultures, has been a central goal in the quest to understand biodiversity effects on ecosystem function. Species contributions to ecosystem function can be driven by two processes: niche complementarity and a selection effect that is influenced by fitness (competitive) differences, and both can be approximated with measures of species' traits. It has been hypothesised that fitness differences are associated with few, singular traits while complementarity requires multidimensional trait measures. Here, using experimental data from plant assemblages, I show that the selection effect was strongest when trait dissimilarity was low, while complementarity was greatest with high trait dissimilarity. Selection effects were best explained by a single trait, plant height. Complementarity was correlated with dissimilarity across multiple traits, representing above and below ground processes. By identifying the relevant traits linked to ecosystem function, we obtain the ability to predict combinations of species that will maximise ecosystem function. © 2017 John Wiley & Sons Ltd/CNRS.

Experimental investigation of halogen-bond hard-soft acid-base complementarity.

PubMed

Riel, Asia Marie S; Jessop, Morly J; Decato, Daniel A; Massena, Casey J; Nascimento, Vinicius R; Berryman, Orion B

2017-04-01

The halogen bond (XB) is a topical noncovalent interaction of rapidly increasing importance. The XB employs a `soft' donor atom in comparison to the `hard' proton of the hydrogen bond (HB). This difference has led to the hypothesis that XBs can form more favorable interactions with `soft' bases than HBs. While computational studies have supported this suggestion, solution and solid-state data are lacking. Here, XB soft-soft complementarity is investigated with a bidentate receptor that shows similar associations with neutral carbonyls and heavy chalcogen analogs. The solution speciation and XB soft-soft complementarity is supported by four crystal structures containing neutral and anionic soft Lewis bases.

Climate change mitigation and adaptation in the land use sector: from complementarity to synergy.

PubMed

Duguma, Lalisa A; Minang, Peter A; van Noordwijk, Meine

2014-09-01

Currently, mitigation and adaptation measures are handled separately, due to differences in priorities for the measures and segregated planning and implementation policies at international and national levels. There is a growing argument that synergistic approaches to adaptation and mitigation could bring substantial benefits at multiple scales in the land use sector. Nonetheless, efforts to implement synergies between adaptation and mitigation measures are rare due to the weak conceptual framing of the approach and constraining policy issues. In this paper, we explore the attributes of synergy and the necessary enabling conditions and discuss, as an example, experience with the Ngitili system in Tanzania that serves both adaptation and mitigation functions. An in-depth look into the current practices suggests that more emphasis is laid on complementarity-i.e., mitigation projects providing adaptation co-benefits and vice versa rather than on synergy. Unlike complementarity, synergy should emphasize functionally sustainable landscape systems in which adaptation and mitigation are optimized as part of multiple functions. We argue that the current practice of seeking co-benefits (complementarity) is a necessary but insufficient step toward addressing synergy. Moving forward from complementarity will require a paradigm shift from current compartmentalization between mitigation and adaptation to systems thinking at landscape scale. However, enabling policy, institutional, and investment conditions need to be developed at global, national, and local levels to achieve synergistic goals.

The role of robotics in computer controlled polishing of large and small optics

NASA Astrophysics Data System (ADS)

Walker, David; Dunn, Christina; Yu, Guoyu; Bibby, Matt; Zheng, Xiao; Wu, Hsing Yu; Li, Hongyu; Lu, Chunlian

2015-08-01

Following formal acceptance by ESO of three 1.4m hexagonal off-axis prototype mirror segments, one circular segment, and certification of our optical test facility, we turn our attention to the challenge of segment mass-production. In this paper, we focus on the role of industrial robots, highlighting complementarity with Zeeko CNC polishing machines, and presenting results using robots to provide intermediate processing between CNC grinding and polishing. We also describe the marriage of robots and Zeeko machines to automate currently manual operations; steps towards our ultimate vision of fully autonomous manufacturing cells, with impact throughout the optical manufacturing community and beyond.

Computational studies of new potential antimalarial compounds Stereoelectronic complementarity with the receptor

NASA Astrophysics Data System (ADS)

Portela, César; Afonso, Carlos M. M.; Pinto, Madalena M. M.; João Ramos, Maria

2003-09-01

One of the most important pharmacological mechanisms of antimalarial action is the inhibition of the aggregation of hematin into hemozoin. We present a group of new potential antimalarial molecules for which we have performed a DFT study of their stereoelectronic properties. Additionally, the same calculations were carried out for the two putative drug receptors involved in the referred activity, i.e., hematin μ-oxo dimer and hemozoin. A complementarity between the structural and electronic profiles of the planned molecules and the receptors can be observed. A docking study of the new compounds in relation to the two putative receptors is also presented, providing a correlation with the defined electrostatic complementarity.

Balancing charge in the complementarity-determining regions of humanized mAbs without affecting pI reduces non-specific binding and improves the pharmacokinetics.

PubMed

Datta-Mannan, Amita; Thangaraju, Arunkumar; Leung, Donmienne; Tang, Ying; Witcher, Derrick R; Lu, Jirong; Wroblewski, Victor J

2015-01-01

Lowering the isoelectric point (pI) through engineering the variable region or framework of an IgG can improve its exposure and half-life via a reduction in clearance mediated through non-specific interactions. As such, net charge is a potentially important property to consider in developing therapeutic IgG molecules having favorable pharmaceutical characteristics. Frequently, it may not be possible to shift the pI of monoclonal antibodies (mAbs) dramatically without the introduction of other liabilities such as increased off-target interactions or reduced on-target binding properties. In this report, we explored the influence of more subtle modifications of molecular charge on the in vivo properties of an IgG1 and IgG4 monoclonal antibody. Molecular surface modeling was used to direct residue substitutions in the complementarity-determining regions (CDRs) to disrupt positive charge patch regions, resulting in a reduction in net positive charge without affecting the overall pI of the mAbs. The effect of balancing the net positive charge on non-specific binding was more significant for the IgG4 versus the IgG1 molecule that we examined. This differential effect was connected to the degree of influence on cellular degradation in vitro and in vivo clearance, distribution and metabolism in mice. In the more extreme case of the IgG4, balancing the charge yielded an ∼7-fold improvement in peripheral exposure, as well as significantly reduced tissue catabolism and subsequent excretion of proteolyzed products in urine. Balancing charge on the IgG1 molecule had a more subtle influence on non-specific binding and yielded only a modest alteration in clearance, distribution and elimination. These results suggest that balancing CDR charge without affecting the pI can lead to improved mAb pharmacokinetics, the magnitude of which is likely dependent on the relative influence of charge imbalance and other factors affecting the molecule's disposition.

Balancing charge in the complementarity-determining regions of humanized mAbs without affecting pI reduces non-specific binding and improves the pharmacokinetics

PubMed Central

Datta-Mannan, Amita; Thangaraju, Arunkumar; Leung, Donmienne; Tang, Ying; Witcher, Derrick R; Lu, Jirong; Wroblewski, Victor J

2015-01-01

Lowering the isoelectric point (pI) through engineering the variable region or framework of an IgG can improve its exposure and half-life via a reduction in clearance mediated through non-specific interactions. As such, net charge is a potentially important property to consider in developing therapeutic IgG molecules having favorable pharmaceutical characteristics. Frequently, it may not be possible to shift the pI of monoclonal antibodies (mAbs) dramatically without the introduction of other liabilities such as increased off-target interactions or reduced on-target binding properties. In this report, we explored the influence of more subtle modifications of molecular charge on the in vivo properties of an IgG1 and IgG4 monoclonal antibody. Molecular surface modeling was used to direct residue substitutions in the complementarity-determining regions (CDRs) to disrupt positive charge patch regions, resulting in a reduction in net positive charge without affecting the overall pI of the mAbs. The effect of balancing the net positive charge on non-specific binding was more significant for the IgG4 versus the IgG1 molecule that we examined. This differential effect was connected to the degree of influence on cellular degradation in vitro and in vivo clearance, distribution and metabolism in mice. In the more extreme case of the IgG4, balancing the charge yielded an ∼7-fold improvement in peripheral exposure, as well as significantly reduced tissue catabolism and subsequent excretion of proteolyzed products in urine. Balancing charge on the IgG1 molecule had a more subtle influence on non-specific binding and yielded only a modest alteration in clearance, distribution and elimination. These results suggest that balancing CDR charge without affecting the pI can lead to improved mAb pharmacokinetics, the magnitude of which is likely dependent on the relative influence of charge imbalance and other factors affecting the molecule's disposition. PMID:25695748

Tree Diversity Enhances Stand Carbon Storage but Not Leaf Area in a Subtropical Forest.

PubMed

Castro-Izaguirre, Nadia; Chi, Xiulian; Baruffol, Martin; Tang, Zhiyao; Ma, Keping; Schmid, Bernhard; Niklaus, Pascal A

2016-01-01

Research about biodiversity-productivity relationships has focused on herbaceous ecosystems, with results from tree field studies only recently beginning to emerge. Also, the latter are concentrated largely in the temperate zone. Tree species diversity generally is much higher in subtropical and tropical than in temperate or boreal forests, with reasons not fully understood. Niche overlap and thus complementarity in the use of resources that support productivity may be lower in forests than in herbaceous ecosystems, suggesting weaker productivity responses to diversity change in forests. We studied stand basal area, vertical structure, leaf area, and their relationship with tree species richness in a subtropical forest in south-east China. Permanent forest plots of 30 x 30 m were selected to span largely independent gradients in tree species richness and secondary successional age. Plots with higher tree species richness had a higher stand basal area. Also, stand basal area increases over a 4-year census interval were larger at high than at low diversity. These effects translated into increased carbon stocks in aboveground phytomass (estimated using allometric equations). A higher variability in tree height in more diverse plots suggested that these effects were facilitated by denser canopy packing due to architectural complementarity between species. In contrast, leaf area was not or even negatively affected by tree diversity, indicating a decoupling of carbon accumulation from leaf area. Alternatively, the same community leaf area might have assimilated more C per time interval in more than in less diverse plots because of differences in leaf turnover and productivity or because of differences in the display of leaves in vertical and horizontal space. Overall, our study suggests that in species-rich forests niche-based processes support a positive diversity-productivity relationship and that this translates into increased carbon storage in long-lived woody structures. Given the high growth rates of these forests during secondary succession, our results further indicate that a forest management promoting tree diversity after disturbance may accelerate CO2 sequestration from the atmosphere and thus be relevant in a climate-change context.

Consumer diversity interacts with prey defenses to drive ecosystem function.

PubMed

Rasher, Douglas B; Hoey, Andrew S; Hay, Mark E

2013-06-01

Prey traits linking consumer diversity to ecosystem function remain poorly understood. On tropical coral reefs, herbivores promote coral dominance by suppressing competing macroalgae, but the roles of herbivore identity and diversity, macroalgal defenses, and their interactions in affecting reef resilience and function are unclear. We studied adjacent pairs of no-take marine reserves and fished areas on reefs in Fiji and found that protected reefs supported 7-17x greater biomass, 2-3x higher species richness of herbivorous fishes, and 3-11x more live coral cover than did fished reefs. In contrast, macroalgae were 27-61x more abundant and 3-4x more species-rich on fished reefs. When we transplanted seven common macroalgae from fished reefs into reserves they were rapidly consumed, suggesting that rates of herbivory (ecosystem functioning) differed inside vs. outside reserves. We then video-recorded feeding activity on the same seven macroalgae when transplanted into reserves, and assessed the functional redundancy vs. complementarity of herbivorous fishes consuming these macroalgae. Of 29 species of larger herbivorous fishes on these reefs, only four species accounted for 97% of macroalgal consumption. Two unicornfish consumed a range of brown macroalgae, a parrotfish consumed multiple red algae, and a rabbitfish consumed a green alga, with almost no diet overlap among these groups. The two most chemically rich, allelopathic algae were each consumed by a single, but different, fish species. This striking complementarity resulted from herbivore species differing in their tolerances to macroalgal chemical and structural defenses. A model of assemblage diet breadth based on our feeding observations predicted that high browser diversity would be required for effective control of macroalgae on Fijian reefs. In support of this model, we observed strong negative relationships between herbivore diversity and macroalgal abundance and diversity across the six study reefs. Our findings indicate that the total diet breadth of the herbivore community and the probability of all macroalgae being removed from reefs by herbivores increases with increasing herbivore diversity, but that a few critical species drive this relationship. Therefore, interactions between algal defenses and herbivore tolerances create an essential role for consumer diversity in the functioning and resilience of coral reefs.

Predicting Species-Resolved Macronutrient Acquisition during Succession in a Model Phototrophic Biofilm Using an Integrated ‘Omics Approach

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

Lindemann, Stephen R.; Mobberley, Jennifer M.; Cole, Jessica K.

The principles governing acquisition and interspecies exchange of nutrients in microbial communities and how those exchanges impact community productivity are poorly understood. Here, we examine energy and macronutrient acquisition in unicyanobacterial consortia for which species-resolved genome information exists for all members, allowing us to use multi-omic approaches to predict species’ abilities to acquire resources and examine expression of resource-acquisition genes during succession. Metabolic reconstruction indicated that a majority of heterotrophic community members lacked the genes required to directly acquire the inorganic nutrients provided in culture medium, suggesting high metabolic interdependency. The sole primary producer in consortium UCC-O, cyanobacterium Phormidium sp.more » OSCR, displayed declining expression of energy harvest, carbon fixation, and nitrate and sulfate reduction proteins but sharply increasing phosphate transporter expression over 28 days. Most heterotrophic members likewise exhibited signs of phosphorus starvation during succession. Though similar in their responses to phosphorus limitation, heterotrophs displayed species-specific expression of nitrogen acquisition genes. These results suggest niche partitioning around nitrogen sources may structure the community when organisms directly compete for limited phosphate. Such niche complementarity around nitrogen sources may increase community diversity and productivity in phosphate-limited phototrophic communities.« less

Predicting Species-Resolved Macronutrient Acquisition during Succession in a Model Phototrophic Biofilm Using an Integrated ‘Omics Approach

DOE PAGES

Lindemann, Stephen R.; Mobberley, Jennifer M.; Cole, Jessica K.; ...

2017-06-13

The principles governing acquisition and interspecies exchange of nutrients in microbial communities and how those exchanges impact community productivity are poorly understood. Here, we examine energy and macronutrient acquisition in unicyanobacterial consortia for which species-resolved genome information exists for all members, allowing us to use multi-omic approaches to predict species’ abilities to acquire resources and examine expression of resource-acquisition genes during succession. Metabolic reconstruction indicated that a majority of heterotrophic community members lacked the genes required to directly acquire the inorganic nutrients provided in culture medium, suggesting high metabolic interdependency. The sole primary producer in consortium UCC-O, cyanobacterium Phormidium sp.more » OSCR, displayed declining expression of energy harvest, carbon fixation, and nitrate and sulfate reduction proteins but sharply increasing phosphate transporter expression over 28 days. Most heterotrophic members likewise exhibited signs of phosphorus starvation during succession. Though similar in their responses to phosphorus limitation, heterotrophs displayed species-specific expression of nitrogen acquisition genes. These results suggest niche partitioning around nitrogen sources may structure the community when organisms directly compete for limited phosphate. Such niche complementarity around nitrogen sources may increase community diversity and productivity in phosphate-limited phototrophic communities.« less

Compatibility and Complementarity of Classroom Ecology and Didactique Research Perspectives in Physical Education

ERIC Educational Resources Information Center

Leriche, Jérôme; Desbiens, Jean-François; Amade-Escot, Chantal; Tinning, Richard

2016-01-01

A large diversity of theoretical frameworks exists in the physical education literature. This article focuses on two of those frameworks to examine their compatibility and their complementarity. The classroom ecology paradigm concentrates on the balance between three task systems, two vectors, and programs of actions proposed by the physical…

A Portfolio for Optimal Collaboration of Human and Cyber Physical Production Systems in Problem-Solving

ERIC Educational Resources Information Center

Ansari, Fazel; Seidenberg, Ulrich

2016-01-01

This paper discusses the complementarity of human and cyber physical production systems (CPPS). The discourse of complementarity is elaborated by defining five criteria for comparing the characteristics of human and CPPS. Finally, a management portfolio matrix is proposed for examining the feasibility of optimal collaboration between them. The…

Development blocks in innovation networks: The Swedish manufacturing industry, 1970-2007.

PubMed

Taalbi, Josef

2017-01-01

The notion of development blocks (Dahmén, 1950, 1991) suggests the co-evolution of technologies and industries through complementarities and the overcoming of imbalances. This study proposes and applies a methodology to analyse development blocks empirically. To assess the extent and character of innovational interdependencies between industries the study combines analysis of innovation biographies and statistical network analysis. This is made possible by using data from a newly constructed innovation output database for Sweden. The study finds ten communities of closely related industries in which innovation activity has been prompted by the emergence of technological imbalances or by the exploitation of new technological opportunities. The communities found in the Swedish network of innovation are shown to be stable over time and often characterized by strong user-supplier interdependencies. These findings serve to stress how historical imbalances and opportunities are key to understanding the dynamics of the long-run development of industries and new technologies.

Assessing climate change impact on complementarity between solar and hydro power in areas affected by glacier shrinkage

NASA Astrophysics Data System (ADS)

Diah Puspitarini, Handriyanti; François, Baptiste; Zoccatelli, Davide; Brown, Casey; Creutin, Jean-Dominique; Zaramella, Mattia; Borga, Marco

2017-04-01

Variable Renewable Energy (VRE) sources such as wind, solar and runoff sources are variable in time and space, following their driving weather variables. In this work we aim to analyse optimal mixes of energy sources, i.e. mixes of sources which minimize the deviation between energy load and generation, for a region in the Upper Adige river basin (Eastern Italian Alps) affected by glacier shrinking. The study focuses on hydropower (run of the river - RoR) and solar energy, and analyses the current situation as well different climate change scenarios. Changes in glacier extent in response to climate warming and/or altered precipitation regimes have the potential to substantially alter the magnitude and timing, as well as the spatial variation of watershed-scale hydrologic fluxes. This may change the complementarity with solar power as well. In this study, we analyse the climate change impact on complementarity between RoR and solar using the Decision Scaling approach (Brown et al. 2012). With this approach, the system vulnerability is separated from the climatic hazard that can come from any set of past or future climate conditions. It departs from conventional top-down impact studies because it explores the sensitivity of the system response to a plausible range of climate variations rather than its sensitivity to the time-varying outcome of individual GCM projections. It mainly relies on the development of Climate Response Functions that bring together i) the sensitivity of some system success and/or failure indicators to key external drivers (i.e. mean features of regional climate) and ii) the future values of these drivers as simulated from climate simulation chains. The main VRE sources used in the study region are solar- and hydro-power (with an important fraction of run-of-the river hydropower). The considered indicator of success is the 'energy penetration' coefficient, defined as the long-run percentage of energy demand naturally met by the VRE on an hourly basis. Climate response functions, developed in a 2D climate change space (change in mean temperature and precipitation), are built from multiple hydro-climatic scenarios obtained by perturbing the observed weather time series with the change factor method, and considering given glacier storage states. Climate experiments are further used for assessing these change factors from different emission scenarios, climate models and future prediction lead times. Their positioning on the Climate Response Function allows discussing the risk/opportunities pertaining to changes in VRE penetration in the future. Results show i) the large impact of glacier shrinkage on the complementarity between solar and RoR energy sources and ii) that the impact is decreasing with time, with the main alterations to be expected in the coming 30 years. Brown, C., Ghile, Y., Laverty, M., Li, K., (2012). Decision scaling: Linking bottom up vulnerability analysis with climate projections in the water sector. Water Resour Res 48. 515 doi:10.1029/2011WR011212

The Impact of Electronic Commerce on the Publishing Industry: Towards a Business Value Complementarity Framework of Electronic Publishing.

ERIC Educational Resources Information Center

Scupola, Ada

1999-01-01

Discussion of the publishing industry and its use of information and communication technologies focuses on the way in which electronic-commerce technologies are changing and could change the publishing processes, and develops a business complementarity model of electronic publishing to maximize profitability and improve the competitive position.…

The contribution of community leadership upon the performance of mutual health organisations in Ghana.

PubMed

Adomah-Afari, Augustine

2015-01-01

The purpose of this paper is to investigate the effect of social dynamics on the performance of mutual health organisations (MHOs) exploring the influence of community wealth and community leadership on policy implementation. Four operating district mutual health insurance schemes were selected using geographical locations, among other criteria, as case studies. Data were gathered through interviews and documentary review. The findings were analysed using community field and social capital theories. Traditional leaders like the Chiefs serve as the pivot around which social and human capital of the communities revolve in the developmental process of the country. Lack of exhaustive examination of the financial and institutional viability issues of the MHOs. Future studies could assess the interplay between financial, institutional and social viability models when measuring the financial and overall sustainability of MHOs. Health policy makers need to involve traditional leaders in the formulation and implementation of national policies since their acceptance or rejection of central government policy could have negative consequences. Ghana is a dynamic country and there is the need to utilise existing social networks: inter-family and inter-tribal relationships to ensure the viability of MHOs. There is and can be a successful interplay between public sector funding and community sector revenue mobilisation for financing the health sector in Ghana. This justifies the complementarity between government funding and community's resource mobilisation efforts in the health sector.

On the Embedded Complementarity of Agent-Based and Aggregate Reasoning in Students' Developing Understanding of Dynamic Systems

ERIC Educational Resources Information Center

Stroup, Walter M.; Wilensky, Uri

2014-01-01

Placed in the larger context of broadening the engagement with systems dynamics and complexity theory in school-aged learning and teaching, this paper is intended to introduce, situate, and illustrate--with results from the use of network supported participatory simulations in classrooms--a stance we call "embedded complementarity" as an…

Has Complementarity between Employer-Sponsored Training and Education in the U.S. Changed during the 2000s?

ERIC Educational Resources Information Center

Waddoups, C. Jeffrey

2018-01-01

The study reveals that the positive correlation between formal education and job training (complementarity) has weakened during the 2000s. Using U.S. Census Bureau data from the Survey of Income and Program Participation, the study finds that although workers in all categories of educational attainment felt the decline, the effects were strongest…

Multiple-algorithm parallel fusion of infrared polarization and intensity images based on algorithmic complementarity and synergy

NASA Astrophysics Data System (ADS)

Zhang, Lei; Yang, Fengbao; Ji, Linna; Lv, Sheng

2018-01-01

Diverse image fusion methods perform differently. Each method has advantages and disadvantages compared with others. One notion is that the advantages of different image methods can be effectively combined. A multiple-algorithm parallel fusion method based on algorithmic complementarity and synergy is proposed. First, in view of the characteristics of the different algorithms and difference-features among images, an index vector-based feature-similarity is proposed to define the degree of complementarity and synergy. This proposed index vector is a reliable evidence indicator for algorithm selection. Second, the algorithms with a high degree of complementarity and synergy are selected. Then, the different degrees of various features and infrared intensity images are used as the initial weights for the nonnegative matrix factorization (NMF). This avoids randomness of the NMF initialization parameter. Finally, the fused images of different algorithms are integrated using the NMF because of its excellent data fusing performance on independent features. Experimental results demonstrate that the visual effect and objective evaluation index of the fused images obtained using the proposed method are better than those obtained using traditional methods. The proposed method retains all the advantages that individual fusion algorithms have.

Leveraging genome-wide datasets to quantify the functional role of the anti-Shine-Dalgarno sequence in regulating translation efficiency.

PubMed

Hockenberry, Adam J; Pah, Adam R; Jewett, Michael C; Amaral, Luís A N

2017-01-01

Studies dating back to the 1970s established that sequence complementarity between the anti-Shine-Dalgarno (aSD) sequence on prokaryotic ribosomes and the 5' untranslated region of mRNAs helps to facilitate translation initiation. The optimal location of aSD sequence binding relative to the start codon, the full extents of the aSD sequence and the functional form of the relationship between aSD sequence complementarity and translation efficiency have not been fully resolved. Here, we investigate these relationships by leveraging the sequence diversity of endogenous genes and recently available genome-wide estimates of translation efficiency. We show that-after accounting for predicted mRNA structure-aSD sequence complementarity increases the translation of endogenous mRNAs by roughly 50%. Further, we observe that this relationship is nonlinear, with translation efficiency maximized for mRNAs with intermediate levels of aSD sequence complementarity. The mechanistic insights that we observe are highly robust: we find nearly identical results in multiple datasets spanning three distantly related bacteria. Further, we verify our main conclusions by re-analysing a controlled experimental dataset. © 2017 The Authors.

Plant diversity effects on grassland productivity are robust to both nutrient enrichment and drought

PubMed Central

Isbell, Forest; Manning, Pete; Connolly, John; Bruelheide, Helge; Ebeling, Anne; Roscher, Christiane; van Ruijven, Jasper; Weigelt, Alexandra; Wilsey, Brian; Beierkuhnlein, Carl; de Luca, Enrica; Griffin, John N.; Hautier, Yann; Hector, Andy; Jentsch, Anke; Kreyling, Jürgen; Lanta, Vojtech; Loreau, Michel; Meyer, Sebastian T.; Mori, Akira S.; Naeem, Shahid; Palmborg, Cecilia; Polley, H. Wayne; Reich, Peter B.; Schmid, Bernhard; Siebenkäs, Alrun; Seabloom, Eric; Thakur, Madhav P.; Tilman, David; Vogel, Anja; Eisenhauer, Nico

2016-01-01

Global change drivers are rapidly altering resource availability and biodiversity. While there is consensus that greater biodiversity increases the functioning of ecosystems, the extent to which biodiversity buffers ecosystem productivity in response to changes in resource availability remains unclear. We use data from 16 grassland experiments across North America and Europe that manipulated plant species richness and one of two essential resources—soil nutrients or water—to assess the direction and strength of the interaction between plant diversity and resource alteration on above-ground productivity and net biodiversity, complementarity, and selection effects. Despite strong increases in productivity with nutrient addition and decreases in productivity with drought, we found that resource alterations did not alter biodiversity–ecosystem functioning relationships. Our results suggest that these relationships are largely determined by increases in complementarity effects along plant species richness gradients. Although nutrient addition reduced complementarity effects at high diversity, this appears to be due to high biomass in monocultures under nutrient enrichment. Our results indicate that diversity and the complementarity of species are important regulators of grassland ecosystem productivity, regardless of changes in other drivers of ecosystem function. PMID:27114579

By-product mutualism with evolving common enemies.

PubMed

De Jaegher, Kris

2017-05-07

The common-enemy hypothesis of by-product mutualism states that organisms cooperate when it is in their individual interests to do so, with benefits for other organisms arising as a by-product; in particular, such cooperation is hypothesized to arise when organisms face the common enemy of a sufficiently adverse environment. In an evolutionary game where two defenders can cooperate to defend a common resource, this paper analyzes the common-enemy hypothesis when adversity is endogenous, in that an attacker sets the number of attacks. As a benchmark, we first consider exogenous adversity, where adversity is not subject to evolution. In this case, the common-enemy hypothesis is predicted when the degree of complementarity between defenders' defensive efforts is sufficiently low. When the degree of complementarity is high, the hypothesis is predicted only when cooperation costs are high; when cooperation costs are instead low, a competing hypothesis is predicted, where adversity discourages cooperation. Second, we consider the case of endogenous adversity. In this case, we continue to predict the competing hypothesis for a high degree of complementarity and low cooperation costs. The common-enemy hypothesis, however, only continues to be predicted for the lowest degrees of complementarity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Do ecohydrology and community dynamics feed back to banded-ecosystem structure and productivity?

NASA Astrophysics Data System (ADS)

Callegaro, Chiara; Ursino, Nadia

2016-04-01

Mixed communities including grass, shrubs and trees are often reported to populate self-organized vegetation patterns. Patterns of survey data suggest that species diversity and complementarity strengthen the dynamics of banded environments. Resource scarcity and local facilitation trigger self organization, whereas coexistence of multiple species in vegetated self-organizing patches, implying competition for water and nutrients and favorable reproduction sites, is made possible by differing adaptation strategies. Mixed community spatial self-organization has so far received relatively little attention, compared with local net facilitation of isolated species. We assumed that soil moisture availability is a proxy for the environmental niche of plant species according to Ursino and Callegaro (2016). Our modelling effort was focused on niche differentiation of coexisting species within a tiger bush type ecosystem. By minimal numerical modelling and stability analysis we try to answer a few open scientific questions: Is there an adaptation strategy that increases biodiversity and ecosystem functioning? Does specific adaptation to environmental niches influence the structure of self-organizing vegetation pattern? What specific niche distribution along the environmental gradient gives the highest global productivity?

Herbivore species richness, composition and community structure mediate predator richness effects and top-down control of herbivore biomass.

PubMed

Wilby, Andrew; Orwin, Kate H

2013-08-01

Changes in predator species richness can have important consequences for ecosystem functioning at multiple trophic levels, but these effects are variable and depend on the ecological context in addition to the properties of predators themselves. Here, we report an experimental study to test how species identity, community attributes, and community structure at the herbivore level moderate the effects of predator richness on ecosystem functioning. Using mesocosms containing predatory insects and aphid prey, we independently manipulated species richness at both predator and herbivore trophic levels. Community structure was also manipulated by changing the distribution of herbivore species across two plant species. Predator species richness and herbivore species richness were found to negatively interact to influence predator biomass accumulation, an effect which is hypothesised to be due to the breakdown of functional complementarity among predators in species-rich herbivore assemblages. The strength of predator suppression of herbivore biomass decreased as herbivore species richness and distribution across host plants increased, and positive predator richness effects on herbivore biomass suppression were only observed in herbivore assemblages of relatively low productivity. In summary, the study shows that the species richness, productivity and host plant distribution of prey communities can all moderate the general influence of predators and the emergence of predator species richness effects on ecosystem functioning.

Phylogenetic structure of soil bacterial communities predicts ecosystem functioning.

PubMed

Pérez-Valera, Eduardo; Goberna, Marta; Verdú, Miguel

2015-05-01

Quantifying diversity with phylogeny-informed metrics helps understand the effects of diversity on ecosystem functioning (EF). The sign of these effects remains controversial because phylogenetic diversity and taxonomic identity may interactively influence EF. Positive relationships, traditionally attributed to complementarity effects, seem unimportant in natural soil bacterial communities. Negative relationships could be attributed to fitness differences leading to the overrepresentation of few productive clades, a mechanism recently invoked to assemble soil bacteria communities. We tested in two ecosystems contrasting in terms of environmental heterogeneity whether two metrics of phylogenetic community structure, a simpler measure of phylogenetic diversity (NRI) and a more complex metric incorporating taxonomic identity (PCPS), correctly predict microbially mediated EF. We show that the relationship between phylogenetic diversity and EF depends on the taxonomic identity of the main coexisting lineages. Phylogenetic diversity was negatively related to EF in soils where a marked fertility gradient exists and a single and productive clade (Proteobacteria) outcompete other clades in the most fertile plots. However, phylogenetic diversity was unrelated to EF in soils where the fertility gradient is less marked and Proteobacteria coexist with other abundant lineages. Including the taxonomic identity of bacterial lineages in metrics of phylogenetic community structure allows the prediction of EF in both ecosystems. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A Metasynthesis of the Complementarity of Culturally Responsive and Inquiry-Based Science Education in K-12 Settings: Implications for Advancing Equitable Science Teaching and Learning

ERIC Educational Resources Information Center

Brown, Julie C.

2017-01-01

Employing metasynthesis as a method, this study examined 52 empirical articles on culturally relevant and responsive science education in K-12 settings to determine the nature and scope of complementarity between culturally responsive and inquiry-based science practices (i.e., science and engineering practices identified in the National Research…

Convergence analysis of modulus-based matrix splitting iterative methods for implicit complementarity problems.

PubMed

Wang, An; Cao, Yang; Shi, Quan

2018-01-01

In this paper, we demonstrate a complete version of the convergence theory of the modulus-based matrix splitting iteration methods for solving a class of implicit complementarity problems proposed by Hong and Li (Numer. Linear Algebra Appl. 23:629-641, 2016). New convergence conditions are presented when the system matrix is a positive-definite matrix and an [Formula: see text]-matrix, respectively.

Horizons of description: Black holes and complementarity

NASA Astrophysics Data System (ADS)

Bokulich, Peter Joshua Martin

Niels Bohr famously argued that a consistent understanding of quantum mechanics requires a new epistemic framework, which he named complementarity . This position asserts that even in the context of quantum theory, classical concepts must be used to understand and communicate measurement results. The apparent conflict between certain classical descriptions is avoided by recognizing that their application now crucially depends on the measurement context. Recently it has been argued that a new form of complementarity can provide a solution to the so-called information loss paradox. Stephen Hawking argues that the evolution of black holes cannot be described by standard unitary quantum evolution, because such evolution always preserves information, while the evaporation of a black hole will imply that any information that fell into it is irrevocably lost---hence a "paradox." Some researchers in quantum gravity have argued that this paradox can be resolved if one interprets certain seemingly incompatible descriptions of events around black holes as instead being complementary. In this dissertation I assess the extent to which this black hole complementarity can be undergirded by Bohr's account of the limitations of classical concepts. I begin by offering an interpretation of Bohr's complementarity and the role that it plays in his philosophy of quantum theory. After clarifying the nature of classical concepts, I offer an account of the limitations these concepts face, and argue that Bohr's appeal to disturbance is best understood as referring to these conceptual limits. Following preparatory chapters on issues in quantum field theory and black hole mechanics, I offer an analysis of the information loss paradox and various responses to it. I consider the three most prominent accounts of black hole complementarity and argue that they fail to offer sufficient justification for the proposed incompatibility between descriptions. The lesson that emerges from this dissertation is that we have as much to learn from the limitations facing our scientific descriptions as we do from the successes they enjoy. Because all of our scientific theories offer at best limited, effective accounts of the world, an important part of our interpretive efforts will be assessing the borders of these domains of description.

Mutations in the MicroRNA Complementarity Site of the INCURVATA4 Gene Perturb Meristem Function and Adaxialize Lateral Organs in Arabidopsis1[W

PubMed Central

Ochando, Isabel; Jover-Gil, Sara; Ripoll, Juan José; Candela, Héctor; Vera, Antonio; Ponce, María Rosa; Martínez-Laborda, Antonio; Micol, José Luis

2006-01-01

Here, we describe how the semidominant, gain-of-function icu4-1 and icu4-2 alleles of the INCURVATA4 (ICU4) gene alter leaf phyllotaxis and cell organization in the root apical meristem, reduce root length, and cause xylem overgrowth in the stem. The ICU4 gene was positionally cloned and found to encode the ATHB15 transcription factor, a class III homeodomain/leucine zipper family member, recently named CORONA. The icu4-1 and icu4-2 alleles bear the same point mutation that affects the microRNA complementarity site of ICU4 and is identical to those of several semidominant alleles of the class III homeodomain/leucine zipper family members PHABULOSA and PHAVOLUTA. The icu4-1 and icu4-2 mutations significantly increase leaf transcript levels of the ICU4 gene. The null hst-1 allele of the HASTY gene, which encodes a nucleocytoplasmic transporter, synergistically interacts with icu4-1, the double mutant displaying partial adaxialization of rosette leaves and carpels. Our results suggest that the ICU4 gene has an adaxializing function and that it is down-regulated by microRNAs that require the HASTY protein for their biogenesis. PMID:16617092

Changing ecosystem service values following technological change.

PubMed

Honey-Rosés, Jordi; Schneider, Daniel W; Brozović, Nicholas

2014-06-01

Research on ecosystem services has focused mostly on natural areas or remote places, with less attention given to urban ecosystem services and their relationship with technological change. However, recent work by urban ecologists and urban designers has more closely examined and appreciated the opportunities associated with integrating natural and built infrastructures. Nevertheless, a perception remains in the literature on ecosystem services that technology may easily and irreversibly substitute for services previously obtained from ecosystems, especially when the superiority of the engineered system motivated replacement in the first place. We emphasize that the expected tradeoff between natural and manufactured capital is false. Rather, as argued in other contexts, the adoption of new technologies is complementary to ecosystem management. The complementarity of ecosystem services and technology is illustrated with a case study in Barcelona, Spain where the installation of sophisticated water treatment technology increased the value of the ecosystem services found there. Interestingly, the complementarity between natural and built infrastructures may remain even for the very ecosystems that are affected by the technological change. This finding suggests that we can expect the value of ecosystem services to co-evolve with new technologies. Technological innovation can generate new opportunities to harness value from ecosystems, and the engineered structures found in cities may generate more reliance on ecosystem processes, not less.

Invasive carnivores alter ecological function and enhance complementarity in scavenger assemblages on ocean beaches.

PubMed

Brown, Marion B; Schlacher, Thomas A; Schoeman, David S; Weston, Michael A; Huijbers, Chantal M; Olds, Andrew D; Connolly, Rod M

2015-10-01

Species composition is expected to alter ecological function in assemblages if species traits differ strongly. Such effects are often large and persistent for nonnative carnivores invading islands. Alternatively, high similarity in traits within assemblages creates a degree of functional redundancy in ecosystems. Here we tested whether species turnover results in functional ecological equivalence or complementarity, and whether invasive carnivores on islands significantly alter such ecological function. The model system consisted of vertebrate scavengers (dominated by raptors) foraging on animal carcasses on ocean beaches on two Australian islands, one with and one without invasive red foxes (Vulpes vulpes). Partitioning of scavenging events among species, carcass removal rates, and detection speeds were quantified using camera traps baited with fish carcasses at the dune-beach interface. Complete segregation of temporal foraging niches between mammals (nocturnal) and birds (diurnal) reflects complementarity in carrion utilization. Conversely, functional redundancy exists within the bird guild where several species of raptors dominate carrion removal in a broadly similar way. As predicted, effects of red foxes were large. They substantially changed the nature and rate of the scavenging process in the system: (1) foxes consumed over half (55%) of all carrion available at night, compared with negligible mammalian foraging at night on the fox-free island, and (2) significant shifts in the composition of the scavenger assemblages consuming beach-cast carrion are the consequence of fox invasion at one island. Arguably, in the absence of other mammalian apex predators, the addition of red foxes creates a new dimension of functional complementarity in beach food webs. However, this functional complementarity added by foxes is neither benign nor neutral, as marine carrion subsidies to coastal red fox populations are likely to facilitate their persistence as exotic carnivores.

Testing Electrostatic Complementarity in Enzyme Catalysis: Hydrogen Bonding in the Ketosteroid Isomerase Oxyanion Hole

PubMed Central

Kraut, Daniel A; Sigala, Paul A; Pybus, Brandon; Liu, Corey W; Ringe, Dagmar; Petsko, Gregory A

2006-01-01

A longstanding proposal in enzymology is that enzymes are electrostatically and geometrically complementary to the transition states of the reactions they catalyze and that this complementarity contributes to catalysis. Experimental evaluation of this contribution, however, has been difficult. We have systematically dissected the potential contribution to catalysis from electrostatic complementarity in ketosteroid isomerase. Phenolates, analogs of the transition state and reaction intermediate, bind and accept two hydrogen bonds in an active site oxyanion hole. The binding of substituted phenolates of constant molecular shape but increasing p K a models the charge accumulation in the oxyanion hole during the enzymatic reaction. As charge localization increases, the NMR chemical shifts of protons involved in oxyanion hole hydrogen bonds increase by 0.50–0.76 ppm/p K a unit, suggesting a bond shortening of ˜0.02 Å/p K a unit. Nevertheless, there is little change in binding affinity across a series of substituted phenolates (ΔΔG = −0.2 kcal/mol/p K a unit). The small effect of increased charge localization on affinity occurs despite the shortening of the hydrogen bonds and a large favorable change in binding enthalpy (ΔΔH = −2.0 kcal/mol/p K a unit). This shallow dependence of binding affinity suggests that electrostatic complementarity in the oxyanion hole makes at most a modest contribution to catalysis of ˜300-fold. We propose that geometrical complementarity between the oxyanion hole hydrogen-bond donors and the transition state oxyanion provides a significant catalytic contribution, and suggest that KSI, like other enzymes, achieves its catalytic prowess through a combination of modest contributions from several mechanisms rather than from a single dominant contribution. PMID:16602823

Skill complementarity enhances heterophily in collaboration networks

PubMed Central

Xie, Wen-Jie; Li, Ming-Xia; Jiang, Zhi-Qiang; Tan, Qun-Zhao; Podobnik, Boris; Zhou, Wei-Xing; Stanley, H. Eugene

2016-01-01

Much empirical evidence shows that individuals usually exhibit significant homophily in social networks. We demonstrate, however, skill complementarity enhances heterophily in the formation of collaboration networks, where people prefer to forge social ties with people who have professions different from their own. We construct a model to quantify the heterophily by assuming that individuals choose collaborators to maximize utility. Using a huge database of online societies, we find evidence of heterophily in collaboration networks. The results of model calibration confirm the presence of heterophily. Both empirical analysis and model calibration show that the heterophilous feature is persistent along the evolution of online societies. Furthermore, the degree of skill complementarity is positively correlated with their production output. Our work sheds new light on the scientific research utility of virtual worlds for studying human behaviors in complex socioeconomic systems. PMID:26743687

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

Hart, William E.; Siirola, John Daniel

We describe new capabilities for modeling MPEC problems within the Pyomo modeling software. These capabilities include new modeling components that represent complementar- ity conditions, modeling transformations for re-expressing models with complementarity con- ditions in other forms, and meta-solvers that apply transformations and numeric optimization solvers to optimize MPEC problems. We illustrate the breadth of Pyomo's modeling capabil- ities for MPEC problems, and we describe how Pyomo's meta-solvers can perform local and global optimization of MPEC problems.

Low energy electron catalyst: the electronic origin of catalytic strategies.

PubMed

Davis, Daly; Sajeev, Y

2016-10-12

Using a low energy electron (LEE) as a catalyst, the electronic origin of the catalytic strategies corresponding to substrate selectivity, reaction specificity and reaction rate enhancement is investigated for a reversible unimolecular elementary reaction. An electronic energy complementarity between the catalyst and the substrate molecule is the origin of substrate selectivity and reaction specificity. The electronic energy complementarity is induced by tuning the electronic energy of the catalyst. The energy complementarity maximizes the binding forces between the catalyst and the molecule. Consequently, a new electronically metastable high-energy reactant state and a corresponding new low barrier reaction path are resonantly created for a specific reaction of the substrate through the formation of a catalyst-substrate transient adduct. The LEE catalysis also reveals a fundamental structure-energy correspondence in the formation of the catalyst-substrate transient adduct. Since the energy complementarities corresponding to the substrate molecules of the forward and the backward steps of the reversible reactions are not the same due to their structural differences, the LEE catalyst exhibits a unique one-way catalytic strategy, i.e., the LEE catalyst favors the reversible reaction more effectively in one direction. A characteristic stronger binding of the catalyst to the transition state of the reaction than in the initial reactant state and the final product state is the molecular origin of barrier lowering.

Integrality in Brazil and Venezuela: similarities and complementarities.

PubMed

Santos, Carla Targino Bruno Dos; Barros, Ione Silva; Amorim, Anne Caroline Coelho Leal Árias; Rocha, Dais Gonçalves; Mendonça, Ana Valéria Machado; Sousa, Maria Fátima de

2018-04-01

This study aims to compare Primary Health Care (PHC) in Brazil and Venezuela, considering its characteristics as to integrality. It has a qualitative approach, using documental analysis, semi-structured interviews with key informants and field diary notes. We observed the three realms of integrality inherent to the health work process: comprehensive and holistic care, the individual viewed as a complex being with multiple needs, requiring the connection of various health knowledge; continuity of care in institutional micro-policy with interprofessional articulation, in order to consider individual care; continuity of care in macro-policy, when a shift to other levels of care is needed; intersectoriality was also included, when the needs of an individual and community require a cross-sectoral coordination, with action on determinants and conditionants of the health-disease process. It is worth highlighting the natural tendency to include a comprehensive community medical training. We conclude that those countries strengthened by democracy draw their integrality practices closer, as well as the construction of social and health policies for underprivileged populations to achieve equity.

An improved error bound for linear complementarity problems for B-matrices.

PubMed

Gao, Lei; Li, Chaoqian

2017-01-01

A new error bound for the linear complementarity problem when the matrix involved is a B -matrix is presented, which improves the corresponding result in (Li et al. in Electron. J. Linear Algebra 31(1):476-484, 2016). In addition some sufficient conditions such that the new bound is sharper than that in (García-Esnaola and Peña in Appl. Math. Lett. 22(7):1071-1075, 2009) are provided.

Correlation complementarity yields bell monogamy relations.

PubMed

Kurzyński, P; Paterek, T; Ramanathan, R; Laskowski, W; Kaszlikowski, D

2011-05-06

We present a method to derive Bell monogamy relations by connecting the complementarity principle with quantum nonlocality. The resulting monogamy relations are stronger than those obtained from the no-signaling principle alone. In many cases, they yield tight quantum bounds on the amount of violation of single and multiple qubit correlation Bell inequalities. In contrast with the two-qubit case, a rich structure of possible violation patterns is shown to exist in the multipartite scenario.

Bohrian Complementarity in the Light of Kantian Teleology

NASA Astrophysics Data System (ADS)

Pringe, Hernán

2014-03-01

The Kantian influences on Bohr's thought and the relationship between the perspective of complementarity in physics and in biology seem at first sight completely unrelated issues. However, the goal of this work is to show their intimate connection. We shall see that Bohr's views on biology shed light on Kantian elements of his thought, which enables a better understanding of his complementary interpretation of quantum theory. For this purpose, we shall begin by discussing Bohr's views on the analogies concerning the epistemological situation in biology and in physics. Later, we shall compare the Bohrian and the Kantian approaches to the science of life in order to show their close connection. On this basis, we shall finally turn to the issue of complementarity in quantum theory in order to assess what we can learn about the epistemological problems in the quantum realm from a consideration of Kant's views on teleology.

Bohr, Heisenberg and the divergent views of complementarity

NASA Astrophysics Data System (ADS)

Camilleri, Kristian

The fractious discussions between Bohr and Heisenberg in Copenhagen in 1927 have been the subject of much historical scholarship. However, little attention has been given to Heisenberg's understanding of the notion of complementary space-time and causal descriptions, which was presented for the first time in Bohr's lecture at the 1927 Como conference. In this paper, I argue that Heisenberg's own interpretation of this notion differed substantially from Bohr's. Whereas Bohr had intended this form of complementarity to entail a choice between a space-time description of the electron in an atom, and defining the energy of a stationary state, Heisenberg interpreted the 'causal' description in terms of ψ -function in configuration space. In disentangling the two views of complementarity, this paper sheds new light on the hidden philosophical disagreements between the proponents of these two founders of the so-called 'Copenhagen interpretation' of quantum mechanics.

Experimental evaluation of diversity-productivity relationships in a coral reef fish assemblage.

PubMed

Messmer, Vanessa; Blowes, Shane A; Jones, Geoffrey P; Munday, Philip L

2014-09-01

The global decline in biodiversity is causing increasing concern about the effects of biodiversity loss on ecosystem services such as productivity. Biodiversity has been hypothesised to be important in maintaining productivity of biological assemblages because niche complementarity and facilitation among the constituent species can result in more efficient use of resources. However, these conclusions are primarily based on studies with plant communities, and the relationship between diversity and productivity at higher trophic levels is largely unknown, especially in the marine environment. Here, we used a manipulative field experiment to test the effects of species richness and species identity on biomass accumulation in coral reef fish assemblages at Lizard Island. Small patch reefs were stocked with a total of 30 juveniles belonging to three planktivorous damselfish (genus Pomacentrus) according to three different levels of fish species richness (one, two and three species) and seven different combinations of fish species. Species richness had no effect on the relative growth in this assemblage after 18 days, but relative growth differed among individual fish species and the different combinations of species. Patterns of increase in biomass were best explained by species-specific differences and variable effects of intra- and interspecific competition on growth. These results suggest that niche complementarity and facilitation are not the most influential drivers of total productivity within this guild of planktivorous fishes. Total productivity may be resilient to declining reef fish biodiversity, but this will depend on which species are lost and on the life-history traits of remaining species.

Consumer diversity interacts with prey defenses to drive ecosystem function

PubMed Central

Rasher, Douglas B.; Hoey, Andrew S.; Hay, Mark E.

2013-01-01

Prey traits linking consumer diversity to ecosystem function remain poorly understood. On tropical coral reefs, herbivores promote coral dominance by suppressing competing macroalgae, but the roles of herbivore identity and diversity, macroalgal defenses, and their interactions in affecting reef resilience and function are unclear. We studied adjacent pairs of no-take marine reserves and fished areas on reefs in Fiji, and found that protected reefs supported 7–17x greater biomass and 2–3x higher species richness of herbivorous fishes, and 3–11x more live coral cover than did fished reefs. In contrast, macroalgae were 27–61x more abundant and 3–4x more species rich on fished reefs. When we transplanted seven common macroalgae from fished reefs into reserves they were rapidly consumed, suggesting that rates of herbivory (ecosystem functioning) differed inside versus outside reserves. We then video recorded feeding activity on the same seven macroalgae when transplanted into reserves, and assessed the functional redundancy versus complementarity of herbivorous fishes consuming these macroalgae. Of 29 species of larger herbivorous fishes on these reefs, only four species accounted for 97% of macroalgal consumption. Two unicornfish consumed a range of brown macroalgae, a parrotfish consumed multiple red algae, and a rabbitfish consumed a green alga, with almost no diet overlap among these groups. The two most chemically rich, allelopathic algae were each consumed by a single, but different, fish species. This striking complementarity resulted from herbivore species differing in their tolerances to macroalgal chemical and structural defenses. A model of assemblage diet breadth based on our feeding observations predicted that high browser diversity would be required for effective control of macroalgae on Fijian reefs. In support of this model, we observed strong, negative relationships between herbivore diversity and macroalgal abundance and diversity across the six study reefs. Our findings indicate that the total diet breadth of the herbivore community and the probability of all macroalgae being removed from reefs by herbivores increases with increasing herbivore diversity, but that a few critical species drive this relationship. Therefore, interactions between algal defenses and herbivore tolerances create an essential role for consumer diversity in the functioning and resilience of coral reefs. PMID:23923498

Bringing physics to bear on the phenomenon of life: the divergent positions of Bohr, Delbrück, and Schrödinger.

PubMed

Domondon, Andrew T

2006-09-01

The received view on the contributions of the physics community to the birth of molecular biology tends to present the physics community as sharing a basic level consensus on how physics should be brought to bear on biology. I argue, however, that a close examination of the views of three leading physicists involved in the birth of molecular biology, Bohr, Delbrück, and Schrödinger, suggests that there existed fundamental disagreements on how physics should be employed to solve problems in biology even within the physics community. In particular, I focus on how these three figures differed sharply in their assessment of the relevance of complementarity, the potential of chemical methods, and the relative importance of classical physics. In addition, I assess and develop Roll-Hansen's attempt to conceptualize this history in terms of models of scientific change advanced by Kuhn and Lakatos. Though neither model is fully successful in explaining the divergence of views among these three physicists, I argue that the extent and quality of difference in their views help elucidate and extend some themes that are left opaque in Kuhn's model.

Functional identity and diversity of animals predict ecosystem functioning better than species-based indices

PubMed Central

Gagic, Vesna; Bartomeus, Ignasi; Jonsson, Tomas; Taylor, Astrid; Winqvist, Camilla; Fischer, Christina; Slade, Eleanor M.; Steffan-Dewenter, Ingolf; Emmerson, Mark; Potts, Simon G.; Tscharntke, Teja; Weisser, Wolfgang; Bommarco, Riccardo

2015-01-01

Drastic biodiversity declines have raised concerns about the deterioration of ecosystem functions and have motivated much recent research on the relationship between species diversity and ecosystem functioning. A functional trait framework has been proposed to improve the mechanistic understanding of this relationship, but this has rarely been tested for organisms other than plants. We analysed eight datasets, including five animal groups, to examine how well a trait-based approach, compared with a more traditional taxonomic approach, predicts seven ecosystem functions below- and above-ground. Trait-based indices consistently provided greater explanatory power than species richness or abundance. The frequency distributions of single or multiple traits in the community were the best predictors of ecosystem functioning. This implies that the ecosystem functions we investigated were underpinned by the combination of trait identities (i.e. single-trait indices) and trait complementarity (i.e. multi-trait indices) in the communities. Our study provides new insights into the general mechanisms that link biodiversity to ecosystem functioning in natural animal communities and suggests that the observed responses were due to the identity and dominance patterns of the trait composition rather than the number or abundance of species per se. PMID:25567651

COMplementary Primer ASymmetric PCR (COMPAS-PCR) Applied to the Identification of Salmo salar, Salmo trutta and Their Hybrids

PubMed Central

2016-01-01

Avoiding complementarity between primers when designing a PCR assay constitutes a central rule strongly anchored in the mind of the molecular scientist. 3’-complementarity will extend the primers during PCR elongation using one another as template, consequently disabling further possible involvement in traditional target amplification. However, a 5’-complementarity will leave the primers unchanged during PCR cycles, albeit sequestered to one another, therefore also suppressing target amplification. We show that 5’-complementarity between primers may be exploited in a new PCR method called COMplementary-Primer-Asymmetric (COMPAS)-PCR, using asymmetric primer concentrations to achieve target PCR amplification. Moreover, such a design may paradoxically reduce spurious non-target amplification by actively sequestering the limiting primer. The general principles were demonstrated using 5S rDNA direct repeats as target sequences to design a species-specific assay for identifying Salmo salar and Salmo trutta using almost fully complementary primers overlapping the same target sequence. Specificity was enhanced by using 3’-penultimate point mutations and the assay was further developed to enable identification of S. salar x S. trutta hybrids by High Resolution Melt analysis in a 35 min one-tube assay. This small paradigm shift, using highly complementary primers for PCR, should help develop robust assays that previously would not be considered. PMID:27783658

CPdock: the complementarity plot for docking of proteins: implementing multi-dielectric continuum electrostatics.

PubMed

Basu, Sankar

2017-12-07

The complementarity plot (CP) is an established validation tool for protein structures, applicable to both globular proteins (folding) as well as protein-protein complexes (binding). It computes the shape and electrostatic complementarities (S m , E m ) for amino acid side-chains buried within the protein interior or interface and plots them in a two-dimensional plot having knowledge-based probabilistic quality estimates for the residues as well as for the whole structure. The current report essentially presents an upgraded version of the plot with the implementation of the advanced multi-dielectric functionality (as in Delphi version 6.2 or higher) in the computation of electrostatic complementarity to make the validation tool physico-chemically more realistic. The two methods (single- and multi-dielectric) agree decently in their resultant E m values, and hence, provisions for both methods have been kept in the software suite. So to speak, the global electrostatic balance within a well-folded protein and/or a well-packed interface seems only marginally perturbed by the choice of different internal dielectric values. However, both from theoretical as well as practical grounds, the more advanced multi-dielectric version of the plot is certainly recommended for potentially producing more reliable results. The report also presents a new methodology and a variant plot, namely CP dock , based on the same principles of complementarity specifically designed to be used in the docking of proteins. The efficacy of the method to discriminate between good and bad docked protein complexes has been tested on a recent state-of-the-art docking benchmark. The results unambiguously indicate that CP dock can indeed be effective in the initial screening phase of a docking scoring pipeline before going into more sophisticated and computationally expensive scoring functions. CP dock has been made available at https://github.com/nemo8130/CPdock . Graphical Abstract An example showing the efficacy of CP dock to be used in the initial screening phase of a protein-protein docking scoring pipeline.

Measuring disaster-resilient communities: a case study of coastal communities in Indonesia.

PubMed

Kafle, Shesh Kanta

2012-01-01

Vulnerability reduction and resilience building of communities are central concepts in recent policy debates. Although there are fundamental linkages, and complementarities exist between the two concepts, recent policy and programming has focused more on the latter. It is assumed here that reducing underlying causes of vulnerabilities and their interactions with resilience elements is a prerequisite for obtaining resilience capabilities. An integrated approach, incorporating both the vulnerability and resilience considerations, has been taken while developing an index for measuring disaster-resilient communities. This study outlines a method for measuring community resilience capabilities using process and outcome indicators in 43 coastal communities in Indonesia. An index was developed using ten process and 25 outcome indicators, selected on the basis of the ten steps of the Integrated Community Based Risk Reduction (ICBRR) process, and key characteristics of disaster resilient communities were taken from various literatures. The overall index value of all 43 communities was 63, whereas the process and outcome indicator values were measured as 63 and 61.5 respectively. The core components of this index are process and outcome indicators. The tool has been developed with an assumption that both the process and outcome indicators are equally important in building disaster-resilient communities. The combination of both indicators is an impetus to quality change in the community. Process indicators are important for community understanding, ownership and the sustainability of the programme; whereas outcome indicators are important for the real achievements in terms of community empowerment and capacity development. The process of ICBRR approach varies by country and location as per the level of community awareness and organisational strategy. However, core elements such as the formation of community groups, mobilising those groups in risk assessment and planning should be present in all the countries or locations. As this study shows, community resiliency can be measured but any such measurement must be both location- and hazard-specific.

Antiandrogenic steroidal sulfonyl heterocycles. Utility of electrostatic complementarity in defining bioisosteric sulfonyl heterocycles.

PubMed

Mallamo, J P; Pilling, G M; Wetzel, J R; Kowalczyk, P J; Bell, M R; Kullnig, R K; Batzold, F H; Juniewicz, P E; Winneker, R C; Luss, H R

1992-05-15

Complementarity of electrostatic potential surface maps was utilized in defining bioisosteric steroidal androgen receptor antagonists. Semiempirical and ab initio level calculations performed on a series of methanesulfonyl heterocycles indicated the requirement for a partial negative charge at the heteroatom attached to C-3 of the steroid nucleus to attain androgen receptor affinity. Synthesis and testing of six heterocycle A-ring-fused dihydroethisterone derivatives support this hypothesis, and we have identified two new androgen receptor antagonists of this class.

Hybrid ququart-encoded quantum cryptography protected by Kochen-Specker contextuality

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

Cabello, Adan; Department of Physics, Stockholm University, S-10691 Stockholm; D'Ambrosio, Vincenzo

2011-09-15

Quantum cryptographic protocols based on complementarity are not secure against attacks in which complementarity is imitated with classical resources. The Kochen-Specker (KS) theorem provides protection against these attacks, without requiring entanglement or spatially separated composite systems. We analyze the maximum tolerated noise to guarantee the security of a KS-protected cryptographic scheme against these attacks and describe a photonic realization of this scheme using hybrid ququarts defined by the polarization and orbital angular momentum of single photons.

Spatial pattern affects diversity-productivity relationships in experimental meadow communities

NASA Astrophysics Data System (ADS)

Lamošová, Tereza; Doležal, Jiří; Lanta, Vojtěch; Lepš, Jan

2010-05-01

Plant species create aggregations of conspecifics as a consequence of limited seed dispersal, clonal growth and heterogeneous environment. Such intraspecific aggregation increases the importance of intraspecific competition relative to interspecific competition which may slow down competitive exclusion and promote species coexistence. To examine how spatial aggregation impacts the functioning of experimental assemblages of varying species richness, eight perennial grassland species of different growth form were grown in random and aggregated patterns in monocultures, two-, four-, and eight-species mixtures. In mixtures with an aggregated pattern, monospecific clumps were interspecifically segregated. Mixed model ANOVA was used to test (i) how the total productivity and productivity of individual species is affected by the number of species in a mixture, and (ii) how these relationships are affected by spatial pattern of sown plants. The main patterns of productivity response to species richness conform to other studies: non-transgressive overyielding is omnipresent (the productivity of mixtures is higher than the average of its constituent species so that the net diversity, selection and complementarity effects are positive), whereas transgressive overyielding is found only in a minority of cases (average of log(overyielding) being close to zero or negative). The theoretical prediction that plants in a random pattern should produce more than in an aggregated pattern (the distances to neighbours are smaller and consequently the competition among neighbours stronger) was confirmed in monocultures of all the eight species. The situation is more complicated in mixtures, probably as a consequence of complicated interplay between interspecific and intraspecific competition. The most productive species ( Achillea, Holcus, Plantago) were competitively superior and increased their relative productivity with mixture richness. The intraspecific competition of these species is stronger than that of most other species. The aggregated pattern in the full mixture increased the survival of subordinate species, and consequently, we conclude that an aggregated pattern can promote species coexistence (or at least postpone competitive exclusion), particularly in comparison with homogeneously sown mixtures.

Wave-particle dualism and complementarity unraveled by a different mode

PubMed Central

Menzel, Ralf; Puhlmann, Dirk; Heuer, Axel; Schleich, Wolfgang P.

2012-01-01

The precise knowledge of one of two complementary experimental outcomes prevents us from obtaining complete information about the other one. This formulation of Niels Bohr’s principle of complementarity when applied to the paradigm of wave-particle dualism—that is, to Young’s double-slit experiment—implies that the information about the slit through which a quantum particle has passed erases interference. In the present paper we report a double-slit experiment using two photons created by spontaneous parametric down-conversion where we observe interference in the signal photon despite the fact that we have located it in one of the slits due to its entanglement with the idler photon. This surprising aspect of complementarity comes to light by our special choice of the TEM01 pump mode. According to quantum field theory the signal photon is then in a coherent superposition of two distinct wave vectors giving rise to interference fringes analogous to two mechanical slits. PMID:22628561

Profiling charge complementarity and selectivity for binding at the protein surface.

PubMed

Sulea, Traian; Purisima, Enrico O

2003-05-01

A novel analysis and representation of the protein surface in terms of electrostatic binding complementarity and selectivity is presented. The charge optimization methodology is applied in a probe-based approach that simulates the binding process to the target protein. The molecular surface is color coded according to calculated optimal charge or according to charge selectivity, i.e., the binding cost of deviating from the optimal charge. The optimal charge profile depends on both the protein shape and charge distribution whereas the charge selectivity profile depends only on protein shape. High selectivity is concentrated in well-shaped concave pockets, whereas solvent-exposed convex regions are not charge selective. This suggests the synergy of charge and shape selectivity hot spots toward molecular selection and recognition, as well as the asymmetry of charge selectivity at the binding interface of biomolecular systems. The charge complementarity and selectivity profiles map relevant electrostatic properties in a readily interpretable way and encode information that is quite different from that visualized in the standard electrostatic potential map of unbound proteins.

Complementarity of PALM and SOFI for super-resolution live-cell imaging of focal adhesions

PubMed Central

Deschout, Hendrik; Lukes, Tomas; Sharipov, Azat; Szlag, Daniel; Feletti, Lely; Vandenberg, Wim; Dedecker, Peter; Hofkens, Johan; Leutenegger, Marcel; Lasser, Theo; Radenovic, Aleksandra

2016-01-01

Live-cell imaging of focal adhesions requires a sufficiently high temporal resolution, which remains a challenge for super-resolution microscopy. Here we address this important issue by combining photoactivated localization microscopy (PALM) with super-resolution optical fluctuation imaging (SOFI). Using simulations and fixed-cell focal adhesion images, we investigate the complementarity between PALM and SOFI in terms of spatial and temporal resolution. This PALM-SOFI framework is used to image focal adhesions in living cells, while obtaining a temporal resolution below 10 s. We visualize the dynamics of focal adhesions, and reveal local mean velocities around 190 nm min−1. The complementarity of PALM and SOFI is assessed in detail with a methodology that integrates a resolution and signal-to-noise metric. This PALM and SOFI concept provides an enlarged quantitative imaging framework, allowing unprecedented functional exploration of focal adhesions through the estimation of molecular parameters such as fluorophore densities and photoactivation or photoswitching kinetics. PMID:27991512

Complementarity of PALM and SOFI for super-resolution live-cell imaging of focal adhesions

NASA Astrophysics Data System (ADS)

Deschout, Hendrik; Lukes, Tomas; Sharipov, Azat; Szlag, Daniel; Feletti, Lely; Vandenberg, Wim; Dedecker, Peter; Hofkens, Johan; Leutenegger, Marcel; Lasser, Theo; Radenovic, Aleksandra

2016-12-01

Live-cell imaging of focal adhesions requires a sufficiently high temporal resolution, which remains a challenge for super-resolution microscopy. Here we address this important issue by combining photoactivated localization microscopy (PALM) with super-resolution optical fluctuation imaging (SOFI). Using simulations and fixed-cell focal adhesion images, we investigate the complementarity between PALM and SOFI in terms of spatial and temporal resolution. This PALM-SOFI framework is used to image focal adhesions in living cells, while obtaining a temporal resolution below 10 s. We visualize the dynamics of focal adhesions, and reveal local mean velocities around 190 nm min-1. The complementarity of PALM and SOFI is assessed in detail with a methodology that integrates a resolution and signal-to-noise metric. This PALM and SOFI concept provides an enlarged quantitative imaging framework, allowing unprecedented functional exploration of focal adhesions through the estimation of molecular parameters such as fluorophore densities and photoactivation or photoswitching kinetics.

Complementarity of PALM and SOFI for super-resolution live-cell imaging of focal adhesions.

PubMed

Deschout, Hendrik; Lukes, Tomas; Sharipov, Azat; Szlag, Daniel; Feletti, Lely; Vandenberg, Wim; Dedecker, Peter; Hofkens, Johan; Leutenegger, Marcel; Lasser, Theo; Radenovic, Aleksandra

2016-12-19

Live-cell imaging of focal adhesions requires a sufficiently high temporal resolution, which remains a challenge for super-resolution microscopy. Here we address this important issue by combining photoactivated localization microscopy (PALM) with super-resolution optical fluctuation imaging (SOFI). Using simulations and fixed-cell focal adhesion images, we investigate the complementarity between PALM and SOFI in terms of spatial and temporal resolution. This PALM-SOFI framework is used to image focal adhesions in living cells, while obtaining a temporal resolution below 10 s. We visualize the dynamics of focal adhesions, and reveal local mean velocities around 190 nm min -1 . The complementarity of PALM and SOFI is assessed in detail with a methodology that integrates a resolution and signal-to-noise metric. This PALM and SOFI concept provides an enlarged quantitative imaging framework, allowing unprecedented functional exploration of focal adhesions through the estimation of molecular parameters such as fluorophore densities and photoactivation or photoswitching kinetics.

Electrostatics in protein–protein docking

PubMed Central

Heifetz, Alexander; Katchalski-Katzir, Ephraim; Eisenstein, Miriam

2002-01-01

A novel geometric-electrostatic docking algorithm is presented, which tests and quantifies the electrostatic complementarity of the molecular surfaces together with the shape complementarity. We represent each molecule to be docked as a grid of complex numbers, storing information regarding the shape of the molecule in the real part and information regarding the electrostatic character of the molecule in the imaginary part. The electrostatic descriptors are derived from the electrostatic potential of the molecule. Thus, the electrostatic character of the molecule is represented as patches of positive, neutral, or negative values. The potential for each molecule is calculated only once and stored as potential spheres adequate for exhaustive rotation/translation scans. The geometric-electrostatic docking algorithm is applied to 17 systems, starting form the structures of the unbound molecules. The results—in terms of the complementarity scores of the nearly correct solutions, their ranking in the lists of sorted solutions, and their statistical uniqueness—are compared with those of geometric docking, showing that the inclusion of electrostatic complementarity in docking is very important, in particular in docking of unbound structures. Based on our results, we formulate several "good electrostatic docking rules": The geometric-electrostatic docking procedure is more successful than geometric docking when the potential patches are large and when the potential extends away from the molecular surface and protrudes into the solvent. In contrast, geometric docking is recommended when the electrostatic potential around the molecules to be docked appears homogenous, that is, with a similar sign all around the molecule. PMID:11847280

Evidence for Context-Dependent Complementarity of Non-Shine-Dalgarno Ribosome Binding Sites to Escherichia coli rRNA

PubMed Central

Barendt, Pamela A.; Shah, Najaf A.; Barendt, Gregory A.; Kothari, Parth A.; Sarkar, Casim A.

2013-01-01

While the ribosome has evolved to function in complex intracellular environments, these contexts do not easily allow for the study of its inherent capabilities. We have used a synthetic, well-defined, Escherichia coli (E. coli)-based translation system in conjunction with ribosome display, a powerful in vitro selection method, to identify ribosome binding sites (RBSs) that can promote the efficient translation of messenger RNAs (mRNAs) with a leader length representative of natural E. coli mRNAs. In previous work, we used a longer leader sequence and unexpectedly recovered highly efficient cytosine-rich sequences with complementarity to the 16S ribosomal RNA (rRNA) and similarity to eukaryotic RBSs. In the current study, Shine-Dalgarno (SD) sequences were prevalent but non-SD sequences were also heavily enriched and were dominated by novel guanine- and uracil-rich motifs which showed statistically significant complementarity to the 16S rRNA. Additionally, only SD motifs exhibited position-dependent decreases in sequence entropy, indicating that non-SD motifs likely operate by increasing the local concentration of ribosomes in the vicinity of the start codon, rather than by a position-dependent mechanism. These results further support the putative generality of mRNA-rRNA complementarity in facilitating mRNA translation, but also suggest that context (e.g., leader length and composition) dictates the specific subset of possible RBSs that are used for efficient translation of a given transcript. PMID:23427812

Ground Dwelling Ants as Surrogates for Establishing Conservation Priorities in the Australian Wet Tropics

PubMed Central

Yek, Sze Huei; Willliams, Stephen E; Burwell, Chris J.; Robson, Simon K.A.; Crozier, Ross H.

2009-01-01

This study aims to identify a set of areas with high biodiversity value over a small spatial scale within the Australian Wet Tropics. We identified sites of high biodiversity value across an altitudinal gradient of ground dwelling ant communities using three measures of biodiversity. The three measures considered were estimated species richness, complementarity between sites and evolutionary history. The latter measure was derived using the systematic nomenclature of the ants to infer a surrogate phylogeny. The goal of conservation assessments could then be achieved by choosing the most diverse site combinations. This approach was found to be valuable for identifying the most diverse site combinations across an altitudinal gradient that could ensure the preservation of terrestrial ground dwelling invertebrates in the Australian Wet Tropics. PMID:19613441

Keystone nonconsumptive effects within a diverse predator community.

PubMed

Meadows, Amanda J; Owen, Jeb P; Snyder, William E

2017-12-01

The number of prey killed by diverse predator communities is determined by complementarity and interference among predators, and by traits of particular predator species. However, it is less clear how predators' nonconsumptive effects (NCEs) scale with increasing predator biodiversity. We examined NCEs exerted on Culex mosquitoes by a diverse community of aquatic predators. In the field, mosquito larvae co-occurred with differing densities and species compositions of mesopredator insects; top predator dragonfly naiads were present in roughly half of surveyed water bodies. We reproduced these predator community features in artificial ponds, exposing mosquito larvae to predator cues and measuring resulting effects on mosquito traits throughout development. Nonconsumptive effects of various combinations of mesopredator species reduced the survival of mosquito larvae to pupation, and reduced the size and longevity of adult mosquitoes that later emerged from the water. Intriguingly, adding single dragonfly naiads to ponds restored survivorship of larval mosquitoes to levels seen in the absence of predators, and further decreased adult mosquito longevity compared with mosquitoes emerging from mesopredator treatments. Behavioral observations revealed that mosquito larvae regularly deployed "diving" escape behavior in the presence of the mesopredators, but not when a dragonfly naiad was also present. This suggests that dragonflies may have relaxed NCEs of the mesopredators by causing mosquitoes to abandon energetically costly diving. Our study demonstrates that adding one individual of a functionally unique species can substantially alter community-wide NCEs of predators on prey. For pathogen vectors like mosquitoes, this could in turn influence disease dynamics.

Biomass production in experimental grasslands of different species richness during three years of climate warming

NASA Astrophysics Data System (ADS)

de Boeck, H. J.; Lemmens, C. M. H. M.; Gielen, B.; Malchair, S.; Carnol, M.; Merckx, R.; van den Berge, J.; Ceulemans, R.; Nijs, I.

2007-12-01

Here we report on the single and combined impacts of climate warming and species richness on the biomass production in experimental grassland communities. Projections of a future warmer climate have stimulated studies on the response of terrestrial ecosystems to this global change. Experiments have likewise addressed the importance of species numbers for ecosystem functioning. There is, however, little knowledge on the interplay between warming and species richness. During three years, we grew experimental plant communities containing one, three or nine grassland species in 12 sunlit, climate-controlled chambers in Wilrijk, Belgium. Half of these chambers were exposed to ambient air temperatures (unheated), while the other half were warmed by 3°C (heated). Equal amounts of water were added to heated and unheated communities, so that warming would imply drier soils if evapotranspiration was higher. Biomass production was decreased due to warming, both aboveground (-29%) and belowground (-25%), as negative impacts of increased heat and drought stress in summer prevailed. Increased resource partitioning, likely mostly through spatial complementarity, led to higher shoot and root biomass in multi-species communities, regardless of the induced warming. Surprisingly, warming suppressed productivity the most in 9-species communities, which may be attributed to negative impacts of intense interspecific competition for resources under conditions of high abiotic stress. Our results suggest that warming and the associated soil drying could reduce primary production in many temperate grasslands, and that this will not necessarily be mitigated by efforts to maintain or increase species richness.

General monogamy equalities of complementarity relation and distributive entanglement for multi-qubit pure states

NASA Astrophysics Data System (ADS)

Zha, Xinwei; Da, Zhang; Ahmed, Irfan; Zhang, Dan; Zhang, Yanpeng

2018-02-01

In this paper, we determine the complementarity relations for pure quantum states of N qubits by presenting the definition of local and non-local forms. By comparing the entanglement monogamy equality proposed by Coffman, Kundu, and Wootters, we prove that there exist strict monogamy laws for quantum correlations in all many-qubit systems. Further, the proper form of general entanglement monogamy equality for arbitrary quantum states is found with the characterization of total quantum correlation of qubits. These results may open a new window for multi-qubit entanglement.

The Role of Narratives in Sociohydrological Models of Flood Behaviors

NASA Astrophysics Data System (ADS)

Leong, Ching

2018-04-01

While current efforts to model sociohydrologic phenomena provide crucial insight, critics argue that these do not fully reflect the complexity one observes empirically in the real world. The policy sciences, with its focus on the interaction between human agency and the institutions that constrain public choice, can complement such efforts by providing a narrative approach. This paper demonstrates this complementarity by investigating the idea of resilience in a community response to floods. Using the quantitative Q methodology, we trace the dynamics of a common sociohydrologic hypothesis—the "memory effect" and how it decreases vulnerability and, more crucially, the instances when such memory effects do not obtain. Our analysis of a floodprone maladaptive community in Assam, India, finds four distinct narrative types: the Hardened Preparer, the Engineer, Discontent, and the Pessimist. This paper put forward an explicitly sociohydrological conception of resilience which takes into account the role of sociological indicators such as narrative types and perceptions. Such contextual understandings and narrative types can form the basis of generic resilience indicators which complement the anticipated outcomes of sociohydrologic models generally.

"It's What We Use as a Community": Exploring Students' STEM Characterizations In Two Montessori Elementary Classrooms

NASA Astrophysics Data System (ADS)

Szostkowski, Alaina Hopkins

Integrated science, technology, engineering, and mathematics (STEM) education promises to enhance elementary students' engagement in science and related fields and to cultivate their problem-solving abilities. While STEM has become an increasingly popular reform initiative, it is still developing within the Montessori education community. There is limited research on STEM teaching and learning in Montessori classrooms, particularly from student perspectives. Previous studies suggest productive connections between reform-based pedagogies in mainstream science education and the Montessori method. Greater knowledge of this complementarity, and student perspectives on STEM, may benefit both Montessori and non-Montessori educators. This instrumental case study of two elementary classrooms documented student characterizations of aspects of STEM in the context of integrated STEM instruction over three months in the 2016-2017 school year. Findings show that the Montessori environment played an important role, and that students characterized STEM in inclusive, agentive, connected, helpful, creative, and increasingly critical ways. Implications for teaching and future research offer avenues to envision STEM education more holistically by leveraging the moral and humanistic aspects of Montessori philosophy.

Functional identity and diversity of animals predict ecosystem functioning better than species-based indices.

PubMed

Gagic, Vesna; Bartomeus, Ignasi; Jonsson, Tomas; Taylor, Astrid; Winqvist, Camilla; Fischer, Christina; Slade, Eleanor M; Steffan-Dewenter, Ingolf; Emmerson, Mark; Potts, Simon G; Tscharntke, Teja; Weisser, Wolfgang; Bommarco, Riccardo

2015-02-22

Drastic biodiversity declines have raised concerns about the deterioration of ecosystem functions and have motivated much recent research on the relationship between species diversity and ecosystem functioning. A functional trait framework has been proposed to improve the mechanistic understanding of this relationship, but this has rarely been tested for organisms other than plants. We analysed eight datasets, including five animal groups, to examine how well a trait-based approach, compared with a more traditional taxonomic approach, predicts seven ecosystem functions below- and above-ground. Trait-based indices consistently provided greater explanatory power than species richness or abundance. The frequency distributions of single or multiple traits in the community were the best predictors of ecosystem functioning. This implies that the ecosystem functions we investigated were underpinned by the combination of trait identities (i.e. single-trait indices) and trait complementarity (i.e. multi-trait indices) in the communities. Our study provides new insights into the general mechanisms that link biodiversity to ecosystem functioning in natural animal communities and suggests that the observed responses were due to the identity and dominance patterns of the trait composition rather than the number or abundance of species per se. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Species richness and biomass explain spatial turnover in ecosystem functioning across tropical and temperate ecosystems.

PubMed

Barnes, Andrew D; Weigelt, Patrick; Jochum, Malte; Ott, David; Hodapp, Dorothee; Haneda, Noor Farikhah; Brose, Ulrich

2016-05-19

Predicting ecosystem functioning at large spatial scales rests on our ability to scale up from local plots to landscapes, but this is highly contingent on our understanding of how functioning varies through space. Such an understanding has been hampered by a strong experimental focus of biodiversity-ecosystem functioning research restricted to small spatial scales. To address this limitation, we investigate the drivers of spatial variation in multitrophic energy flux-a measure of ecosystem functioning in complex communities-at the landscape scale. We use a structural equation modelling framework based on distance matrices to test how spatial and environmental distances drive variation in community energy flux via four mechanisms: species composition, species richness, niche complementarity and biomass. We found that in both a tropical and a temperate study region, geographical and environmental distance indirectly influence species richness and biomass, with clear evidence that these are the dominant mechanisms explaining variability in community energy flux over spatial and environmental gradients. Our results reveal that species composition and trait variability may become redundant in predicting ecosystem functioning at the landscape scale. Instead, we demonstrate that species richness and total biomass may best predict rates of ecosystem functioning at larger spatial scales. © 2016 The Author(s).

The Heliophysics Data Environment Today

NASA Technical Reports Server (NTRS)

Fung, Shing F.; McGuire, R.; Roberts, D. A.

2008-01-01

Driven by the nature of the research questions now most critical to further progress in heliophysics science, data-driven research has evolved from a model once centered on individual instrument Principal investigator groups and a circle of immediate collaborators into a more inclusive and open environment where data gathered ay great public cost must then be findable and useable throughout the broad national and international research community. In this paper and as an introduction to this special session, we will draw a picture of existing and evolving resources throughout the heliophyscs community, the capabilities and data now available to end users, and the relationships and complementarity of different elements in the environment today. We will cite the relative roles of mission and instrument data centers and resident archives, multi-mission data centers, and the growing importance of virtual discipline observatories and cross-cutting services including the evolution of a common data dictionary. We will briefly summarize our view of the most important challenges still faced by users and providers, and our vision in ow the efforts today can evolve into a more and more enabling data framework for the global research community to tap the widest range of existing missions and their data to address a full range of critical science questions from the scale of microphysics to the heliospheric system as a whole.

Evaluation of PET texture features with heterogeneous phantoms: complementarity and effect of motion and segmentation method

NASA Astrophysics Data System (ADS)

Carles, M.; Torres-Espallardo, I.; Alberich-Bayarri, A.; Olivas, C.; Bello, P.; Nestle, U.; Martí-Bonmatí, L.

2017-01-01

A major source of error in quantitative PET/CT scans of lung cancer tumors is respiratory motion. Regarding the variability of PET texture features (TF), the impact of respiratory motion has not been properly studied with experimental phantoms. The primary aim of this work was to evaluate the current use of PET texture analysis for heterogeneity characterization in lesions affected by respiratory motion. Twenty-eight heterogeneous lesions were simulated by a mixture of alginate and 18 F-fluoro-2-deoxy-D-glucose (FDG). Sixteen respiratory patterns were applied. Firstly, the TF response for different heterogeneous phantoms and its robustness with respect to the segmentation method were calculated. Secondly, the variability for TF derived from PET image with (gated, G-) and without (ungated, U-) motion compensation was analyzed. Finally, TF complementarity was assessed. In the comparison of TF derived from the ideal contour with respect to TF derived from 40%-threshold and adaptive-threshold PET contours, 7/8 TF showed strong linear correlation (LC) (p  <  0.001, r  >  0.75), despite a significant volume underestimation. Independence of lesion movement (LC in 100% of the combined pairs of movements, p  <  0.05) was obtained for 1/8 TF with U-image (width of the volume-activity histogram, WH) and 4/8 TF with G-image (WH and energy (ENG), local-homogeneity (LH) and entropy (ENT), derived from the co-ocurrence matrix). Their variability in terms of the coefficient of variance ({{C}\\text{V}} ) resulted in {{C}\\text{V}} (WH)  =  0.18 on the U-image and {{C}\\text{V}} (WH)  =  0.24, {{C}\\text{V}} (ENG)  =  0.15, {{C}\\text{V}} (LH)  =  0.07 and {{C}\\text{V}} (ENT)  =  0.06 on the G-image. Apart from WH (r  >  0.9, p  <  0.001), not one of these TF has shown LC with C max. Complementarity was observed for the TF pairs: ENG-LH, CONT (contrast)-ENT and LH-ENT. In conclusion, the effect of respiratory motion should be taken into account when the heterogeneity of lung cancer is quantified on PET/CT images. Despite inaccurate volume delineation, TF derived from 40% and COA contours could be reliable for their prognostic use. The TF that exhibited simultaneous added value and independence of lesion movement were ENG and ENT computed from the G-image. Their use is therefore recommended for heterogeneity quantification of lesions affected by respiratory motion.

Structural Model for the Interaction of a Designed Ankyrin Repeat Protein with the Human Epidermal Growth Factor Receptor 2

PubMed Central

Epa, V. Chandana; Dolezal, Olan; Doughty, Larissa; Xiao, Xiaowen; Jost, Christian; Plückthun, Andreas; Adams, Timothy E.

2013-01-01

Designed Ankyrin Repeat Proteins are a class of novel binding proteins that can be selected and evolved to bind to targets with high affinity and specificity. We are interested in the DARPin H10-2-G3, which has been evolved to bind with very high affinity to the human epidermal growth factor receptor 2 (HER2). HER2 is found to be over-expressed in 30% of breast cancers, and is the target for the FDA-approved therapeutic monoclonal antibodies trastuzumab and pertuzumab and small molecule tyrosine kinase inhibitors. Here, we use computational macromolecular docking, coupled with several interface metrics such as shape complementarity, interaction energy, and electrostatic complementarity, to model the structure of the complex between the DARPin H10-2-G3 and HER2. We analyzed the interface between the two proteins and then validated the structural model by showing that selected HER2 point mutations at the putative interface with H10-2-G3 reduce the affinity of binding up to 100-fold without affecting the binding of trastuzumab. Comparisons made with a subsequently solved X-ray crystal structure of the complex yielded a backbone atom root mean square deviation of 0.84–1.14 Ångstroms. The study presented here demonstrates the capability of the computational techniques of structural bioinformatics in generating useful structural models of protein-protein interactions. PMID:23527120

Functional Consequences of Complementarity-determining Region Deactivation in a Multifunctional Anti-nucleic Acid Antibody*

PubMed Central

Lee, Jiyeon; Kim, Hye-Jin; Roh, Jooho; Seo, Youngsil; Kim, Minjae; Jun, Hye-Ryeong; Pham, Chuong D.; Kwon, Myung-Hee

2013-01-01

Many murine monoclonal anti-DNA antibodies (Abs) derived from mice models for systemic lupus erythematosus have additional cell-penetration and/or nucleic acid-hydrolysis properties. Here, we examined the influence of deactivating each complementarity-determining region (CDR) within a multifunctional anti-nucleic acid antibody (Ab) that possesses these activities, the catalytic 3D8 single chain variable fragment (scFv). CDR-deactivated 3D8 scFv variants were generated by replacing all of the amino acids within each CDR with Gly/Ser residues. The structure of 3D8 scFv accommodated single complete CDR deactivations. Different functional activities of 3D8 scFv were affected differently depending on which CDR was deactivated. The only exception was CDR1, located within the light chain (LCDR1); deactivation of LCDR1 abolished all of the functional activities of 3D8 scFv. A hybrid Ab, HW6/3D8L1, in which the LCDR1 from an unrelated Ab (HW6) was replaced with the LCDR1 from 3D8, acquired all activities associated with the 3D8 scFv. These results suggest that the activity of a multifunctional 3D8 scFv Ab can be modulated by single complete CDR deactivation and that the LCDR1 plays a crucial role in maintaining Ab properties. This study presents a new approach for determining the role of individual CDRs in multifunctional Abs with important implications for the future of Ab engineering. PMID:24155236

Profiling Charge Complementarity and Selectivity for Binding at the Protein Surface

PubMed Central

Sulea, Traian; Purisima, Enrico O.

2003-01-01

A novel analysis and representation of the protein surface in terms of electrostatic binding complementarity and selectivity is presented. The charge optimization methodology is applied in a probe-based approach that simulates the binding process to the target protein. The molecular surface is color coded according to calculated optimal charge or according to charge selectivity, i.e., the binding cost of deviating from the optimal charge. The optimal charge profile depends on both the protein shape and charge distribution whereas the charge selectivity profile depends only on protein shape. High selectivity is concentrated in well-shaped concave pockets, whereas solvent-exposed convex regions are not charge selective. This suggests the synergy of charge and shape selectivity hot spots toward molecular selection and recognition, as well as the asymmetry of charge selectivity at the binding interface of biomolecular systems. The charge complementarity and selectivity profiles map relevant electrostatic properties in a readily interpretable way and encode information that is quite different from that visualized in the standard electrostatic potential map of unbound proteins. PMID:12719221

I-HEDGE: determining the optimum complementary sets of taxa for conservation using evolutionary isolation

PubMed Central

Mooers, Arne Ø.; Caccone, Adalgisa; Russello, Michael A.

2016-01-01

In the midst of the current biodiversity crisis, conservation efforts might profitably be directed towards ensuring that extinctions do not result in inordinate losses of evolutionary history. Numerous methods have been developed to evaluate the importance of species based on their contribution to total phylogenetic diversity on trees and networks, but existing methods fail to take complementarity into account, and thus cannot identify the best order or subset of taxa to protect. Here, we develop a novel iterative calculation of the heightened evolutionary distinctiveness and globally endangered metric (I-HEDGE) that produces the optimal ranked list for conservation prioritization, taking into account complementarity and based on both phylogenetic diversity and extinction probability. We applied this metric to a phylogenetic network based on mitochondrial control region data from extant and recently extinct giant Galápagos tortoises, a highly endangered group of closely related species. We found that the restoration of two extinct species (a project currently underway) will contribute the greatest gain in phylogenetic diversity, and present an ordered list of rankings that is the optimum complementarity set for conservation prioritization. PMID:27635324

I-HEDGE: determining the optimum complementary sets of taxa for conservation using evolutionary isolation.

PubMed

Jensen, Evelyn L; Mooers, Arne Ø; Caccone, Adalgisa; Russello, Michael A

2016-01-01

In the midst of the current biodiversity crisis, conservation efforts might profitably be directed towards ensuring that extinctions do not result in inordinate losses of evolutionary history. Numerous methods have been developed to evaluate the importance of species based on their contribution to total phylogenetic diversity on trees and networks, but existing methods fail to take complementarity into account, and thus cannot identify the best order or subset of taxa to protect. Here, we develop a novel iterative calculation of the heightened evolutionary distinctiveness and globally endangered metric (I-HEDGE) that produces the optimal ranked list for conservation prioritization, taking into account complementarity and based on both phylogenetic diversity and extinction probability. We applied this metric to a phylogenetic network based on mitochondrial control region data from extant and recently extinct giant Galápagos tortoises, a highly endangered group of closely related species. We found that the restoration of two extinct species (a project currently underway) will contribute the greatest gain in phylogenetic diversity, and present an ordered list of rankings that is the optimum complementarity set for conservation prioritization.

Somatic Hypermutation-Induced Changes in the Structure and Dynamics of HIV-1 Broadly Neutralizing Antibodies.

PubMed

Davenport, Thaddeus M; Gorman, Jason; Joyce, M Gordon; Zhou, Tongqing; Soto, Cinque; Guttman, Miklos; Moquin, Stephanie; Yang, Yongping; Zhang, Baoshan; Doria-Rose, Nicole A; Hu, Shiu-Lok; Mascola, John R; Kwong, Peter D; Lee, Kelly K

2016-08-02

Antibody somatic hypermutation (SHM) and affinity maturation enhance antigen recognition by modifying antibody paratope structure to improve its complementarity with the target epitope. SHM-induced changes in paratope dynamics may also contribute to antibody maturation, but direct evidence of this is limited. Here, we examine two classes of HIV-1 broadly neutralizing antibodies (bNAbs) for SHM-induced changes in structure and dynamics, and delineate the effects of these changes on interactions with the HIV-1 envelope glycoprotein (Env). In combination with new and existing structures of unmutated and affinity matured antibody Fab fragments, we used hydrogen/deuterium exchange with mass spectrometry to directly measure Fab structural dynamics. Changes in antibody structure and dynamics were positioned to improve complementarity with Env, with changes in dynamics primarily observed at the paratope peripheries. We conclude that SHM optimizes paratope complementarity to conserved HIV-1 epitopes and restricts the mobility of paratope-peripheral residues to minimize clashes with variable features on HIV-1 Env. Copyright © 2016 Elsevier Ltd. All rights reserved.

Combined model of intrinsic and extrinsic variability for computational network design with application to synthetic biology.

PubMed

Toni, Tina; Tidor, Bruce

2013-01-01

Biological systems are inherently variable, with their dynamics influenced by intrinsic and extrinsic sources. These systems are often only partially characterized, with large uncertainties about specific sources of extrinsic variability and biochemical properties. Moreover, it is not yet well understood how different sources of variability combine and affect biological systems in concert. To successfully design biomedical therapies or synthetic circuits with robust performance, it is crucial to account for uncertainty and effects of variability. Here we introduce an efficient modeling and simulation framework to study systems that are simultaneously subject to multiple sources of variability, and apply it to make design decisions on small genetic networks that play a role of basic design elements of synthetic circuits. Specifically, the framework was used to explore the effect of transcriptional and post-transcriptional autoregulation on fluctuations in protein expression in simple genetic networks. We found that autoregulation could either suppress or increase the output variability, depending on specific noise sources and network parameters. We showed that transcriptional autoregulation was more successful than post-transcriptional in suppressing variability across a wide range of intrinsic and extrinsic magnitudes and sources. We derived the following design principles to guide the design of circuits that best suppress variability: (i) high protein cooperativity and low miRNA cooperativity, (ii) imperfect complementarity between miRNA and mRNA was preferred to perfect complementarity, and (iii) correlated expression of mRNA and miRNA--for example, on the same transcript--was best for suppression of protein variability. Results further showed that correlations in kinetic parameters between cells affected the ability to suppress variability, and that variability in transient states did not necessarily follow the same principles as variability in the steady state. Our model and findings provide a general framework to guide design principles in synthetic biology.

Combined Model of Intrinsic and Extrinsic Variability for Computational Network Design with Application to Synthetic Biology

PubMed Central

Toni, Tina; Tidor, Bruce

2013-01-01

Biological systems are inherently variable, with their dynamics influenced by intrinsic and extrinsic sources. These systems are often only partially characterized, with large uncertainties about specific sources of extrinsic variability and biochemical properties. Moreover, it is not yet well understood how different sources of variability combine and affect biological systems in concert. To successfully design biomedical therapies or synthetic circuits with robust performance, it is crucial to account for uncertainty and effects of variability. Here we introduce an efficient modeling and simulation framework to study systems that are simultaneously subject to multiple sources of variability, and apply it to make design decisions on small genetic networks that play a role of basic design elements of synthetic circuits. Specifically, the framework was used to explore the effect of transcriptional and post-transcriptional autoregulation on fluctuations in protein expression in simple genetic networks. We found that autoregulation could either suppress or increase the output variability, depending on specific noise sources and network parameters. We showed that transcriptional autoregulation was more successful than post-transcriptional in suppressing variability across a wide range of intrinsic and extrinsic magnitudes and sources. We derived the following design principles to guide the design of circuits that best suppress variability: (i) high protein cooperativity and low miRNA cooperativity, (ii) imperfect complementarity between miRNA and mRNA was preferred to perfect complementarity, and (iii) correlated expression of mRNA and miRNA – for example, on the same transcript – was best for suppression of protein variability. Results further showed that correlations in kinetic parameters between cells affected the ability to suppress variability, and that variability in transient states did not necessarily follow the same principles as variability in the steady state. Our model and findings provide a general framework to guide design principles in synthetic biology. PMID:23555205

Dependence of the quark-lepton complementarity on parametrizations of the Cabibbo-Kobayashi-Maskawa and Pontecorvo-Maki-Nakagawa-Sakata matrices

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

Zheng Yajuan

2010-04-01

The quark-lepton complementarity (QLC) is very suggestive in understanding possible relations between quark and lepton mixing matrices. We explore the QLC relations in all the possible angle-phase parametrizations and point out that they can approximately hold in five parametrizations. Furthermore, the vanishing of the smallest mixing angles in the Cabibbo-Kobayashi-Maskawa and Pontecorvo-Maki-Nakagawa-Sakata matrices can make sure that the QLC relations exactly hold in those five parametrizations. Finally, the sensitivity of the QLC relations to radiative corrections is also discussed.

Dark-matter decay as a complementary probe of multicomponent dark sectors.

PubMed

Dienes, Keith R; Kumar, Jason; Thomas, Brooks; Yaylali, David

2015-02-06

In single-component theories of dark matter, the 2→2 amplitudes for dark-matter production, annihilation, and scattering can be related to each other through various crossing symmetries. The detection techniques based on these processes are thus complementary. However, multicomponent theories exhibit an additional direction for dark-matter complementarity: the possibility of dark-matter decay from heavier to lighter components. We discuss how this new detection channel may be correlated with the others, and demonstrate that the enhanced complementarity which emerges can be an important ingredient in probing and constraining the parameter spaces of such models.

Health, Enterprise, and Labor Complementarity in the Household*

PubMed Central

Adhvaryu, Achyuta; Nyshadham, Anant

2017-01-01

We study the role of household enterprise as a coping mechanism after health shocks. Using variation in the cost of traveling to formal sector health facilities to predict recovery from acute illness in Tanzania, we show that individuals with prolonged illness switch from farm labor to enterprise activity. This response occurs along both the extensive (entry) and intensive (capital stock and labor supply) margins. Family members who are not ill exhibit exactly the same pattern of responses. Deriving a simple extension to the canonical agricultural household model, we show that our results suggest complementarities in household labor. PMID:28943705

Niche complementarity due to plasticity in resource use: plant partitioning of chemical N forms.

PubMed

Ashton, Isabel W; Miller, Amy E; Bowman, William D; Suding, Katharine N

2010-11-01

Niche complementarity, in which coexisting species use different forms of a resource, has been widely invoked to explain some of the most debated patterns in ecology, including maintenance of diversity and relationships between diversity and ecosystem function. However, classical models assume resource specialization in the form of distinct niches, which does not obviously apply to the broadly overlapping resource use in plant communities. Here we utilize an experimental framework based on competition theory to test whether plants partition resources via classical niche differentiation or via plasticity in resource use. We explore two alternatives: niche preemption, in which individuals respond to a superior competitor by switching to an alternative, less-used resource, and dominant plasticity, in which superior competitors exhibit high resource use plasticity and shift resource use depending on the competitive environment. We determined competitive ability by measuring growth responses with and without neighbors over a growing season and then used 15N tracer techniques to measure uptake of different nitrogen (N) forms in a field setting. We show that four alpine plant species of differing competitive abilities have statistically indistinguishable uptake patterns (nitrate > ammonium > glycine) in their fundamental niche (without competitors) but differ in whether they shift these uptake patterns in their realized niche (with competitors). Competitively superior species increased their uptake of the most available N form, ammonium, when in competition with the rarer, competitively inferior species. In contrast, the competitively inferior species did not alter its N uptake pattern in competition. The existence of plasticity in resource use among the dominant species provides a mechanism that helps to explain the manner by which plant species with broadly overlapping resource use might coexist.

Facilitative-Competitive Interactions in an Old-Growth Forest: The Importance of Large-Diameter Trees as Benefactors and Stimulators for Forest Community Assembly

PubMed Central

Fichtner, Andreas; Forrester, David I.; Härdtle, Werner; Sturm, Knut; von Oheimb, Goddert

2015-01-01

The role of competition in tree communities is increasingly well understood, while little is known about the patterns and mechanisms of the interplay between above- and belowground competition in tree communities. This knowledge, however, is crucial for a better understanding of community dynamics and developing adaptive near-natural management strategies. We assessed neighbourhood interactions in an unmanaged old-growth European beech (Fagus sylvatica) forest by quantifying variation in the intensity of above- (shading) and belowground competition (crowding) among dominant and co-dominant canopy beech trees during tree maturation. Shading had on average a much larger impact on radial growth than crowding and the sensitivity to changes in competitive conditions was lowest for crowding effects. We found that each mode of competition reduced the effect of the other. Increasing crowding reduced the negative effect of shading, and at high levels of shading, crowding actually had a facilitative effect and increased growth. Our study demonstrates that complementarity in above- and belowground processes enable F. sylvatica to alter resource acquisition strategies, thus optimising tree radial growth. As a result, competition seemed to become less important in stands with a high growing stock and tree communities with a long continuity of anthropogenic undisturbed population dynamics. We suggest that growth rates do not exclusively depend on the density of potential competitors at the intraspecific level, but on the conspecific aggregation of large-diameter trees and their functional role for regulating biotic filtering processes. This finding highlights the potential importance of the rarely examined relationship between the spatial aggregation pattern of large-diameter trees and the outcome of neighbourhood interactions, which may be central to community dynamics and the related forest ecosystem services. PMID:25803035

Facilitative-competitive interactions in an old-growth forest: the importance of large-diameter trees as benefactors and stimulators for forest community assembly.

PubMed

Fichtner, Andreas; Forrester, David I; Härdtle, Werner; Sturm, Knut; von Oheimb, Goddert

2015-01-01

The role of competition in tree communities is increasingly well understood, while little is known about the patterns and mechanisms of the interplay between above- and belowground competition in tree communities. This knowledge, however, is crucial for a better understanding of community dynamics and developing adaptive near-natural management strategies. We assessed neighbourhood interactions in an unmanaged old-growth European beech (Fagus sylvatica) forest by quantifying variation in the intensity of above- (shading) and belowground competition (crowding) among dominant and co-dominant canopy beech trees during tree maturation. Shading had on average a much larger impact on radial growth than crowding and the sensitivity to changes in competitive conditions was lowest for crowding effects. We found that each mode of competition reduced the effect of the other. Increasing crowding reduced the negative effect of shading, and at high levels of shading, crowding actually had a facilitative effect and increased growth. Our study demonstrates that complementarity in above- and belowground processes enable F. sylvatica to alter resource acquisition strategies, thus optimising tree radial growth. As a result, competition seemed to become less important in stands with a high growing stock and tree communities with a long continuity of anthropogenic undisturbed population dynamics. We suggest that growth rates do not exclusively depend on the density of potential competitors at the intraspecific level, but on the conspecific aggregation of large-diameter trees and their functional role for regulating biotic filtering processes. This finding highlights the potential importance of the rarely examined relationship between the spatial aggregation pattern of large-diameter trees and the outcome of neighbourhood interactions, which may be central to community dynamics and the related forest ecosystem services.

Reinforcement learning in complementarity game and population dynamics

NASA Astrophysics Data System (ADS)

Jost, Jürgen; Li, Wei

2014-02-01

We systematically test and compare different reinforcement learning schemes in a complementarity game [J. Jost and W. Li, Physica A 345, 245 (2005), 10.1016/j.physa.2004.07.005] played between members of two populations. More precisely, we study the Roth-Erev, Bush-Mosteller, and SoftMax reinforcement learning schemes. A modified version of Roth-Erev with a power exponent of 1.5, as opposed to 1 in the standard version, performs best. We also compare these reinforcement learning strategies with evolutionary schemes. This gives insight into aspects like the issue of quick adaptation as opposed to systematic exploration or the role of learning rates.

Genetic programming over context-free languages with linear constraints for the knapsack problem: first results.

PubMed

Bruhn, Peter; Geyer-Schulz, Andreas

2002-01-01

In this paper, we introduce genetic programming over context-free languages with linear constraints for combinatorial optimization, apply this method to several variants of the multidimensional knapsack problem, and discuss its performance relative to Michalewicz's genetic algorithm with penalty functions. With respect to Michalewicz's approach, we demonstrate that genetic programming over context-free languages with linear constraints improves convergence. A final result is that genetic programming over context-free languages with linear constraints is ideally suited to modeling complementarities between items in a knapsack problem: The more complementarities in the problem, the stronger the performance in comparison to its competitors.

Structure—activity relationships for insecticidal carbamates*

PubMed Central

Metcalf, Robert L.

1971-01-01

Carbamate insecticides are biologically active because of their structural complementarity to the active site of acetylcholinesterase (AChE) and their consequent action as substrates with very low turnover numbers. Carbamates behave as synthetic neurohormones that produce their toxic action by interrupting the normal action of AChE so that acetylcholine accumulates at synaptic junctions. The necessary properties for a suitable insecticidal carbamate are lipid solubility, suitable structural complementarity to AChE, and sufficient stability to multifunction-oxidase detoxification. The relationships between the structure and the activity of a large number of synthetic carbamates are analysed in detail, with particular attention to the second of these properties. PMID:5315358

Plant genotypic diversity reduces the rate of consumer resource utilization

PubMed Central

McArt, Scott H.; Thaler, Jennifer S.

2013-01-01

While plant species diversity can reduce herbivore densities and herbivory, little is known regarding how plant genotypic diversity alters resource utilization by herbivores. Here, we show that an invasive folivore—the Japanese beetle (Popillia japonica)—increases 28 per cent in abundance, but consumes 24 per cent less foliage in genotypic polycultures compared with monocultures of the common evening primrose (Oenothera biennis). We found strong complementarity for reduced herbivore damage among plant genotypes growing in polycultures and a weak dominance effect of particularly resistant genotypes. Sequential feeding by P. japonica on different genotypes from polycultures resulted in reduced consumption compared with feeding on different plants of the same genotype from monocultures. Thus, diet mixing among plant genotypes reduced herbivore consumption efficiency. Despite positive complementarity driving an increase in fruit production in polycultures, we observed a trade-off between complementarity for increased plant productivity and resistance to herbivory, suggesting costs in the complementary use of resources by plant genotypes may manifest across trophic levels. These results elucidate mechanisms for how plant genotypic diversity simultaneously alters resource utilization by both producers and consumers, and show that population genotypic diversity can increase the resistance of a native plant to an invasive herbivore. PMID:23658201

Plant genotypic diversity reduces the rate of consumer resource utilization.

PubMed

McArt, Scott H; Thaler, Jennifer S

2013-07-07

While plant species diversity can reduce herbivore densities and herbivory, little is known regarding how plant genotypic diversity alters resource utilization by herbivores. Here, we show that an invasive folivore--the Japanese beetle (Popillia japonica)--increases 28 per cent in abundance, but consumes 24 per cent less foliage in genotypic polycultures compared with monocultures of the common evening primrose (Oenothera biennis). We found strong complementarity for reduced herbivore damage among plant genotypes growing in polycultures and a weak dominance effect of particularly resistant genotypes. Sequential feeding by P. japonica on different genotypes from polycultures resulted in reduced consumption compared with feeding on different plants of the same genotype from monocultures. Thus, diet mixing among plant genotypes reduced herbivore consumption efficiency. Despite positive complementarity driving an increase in fruit production in polycultures, we observed a trade-off between complementarity for increased plant productivity and resistance to herbivory, suggesting costs in the complementary use of resources by plant genotypes may manifest across trophic levels. These results elucidate mechanisms for how plant genotypic diversity simultaneously alters resource utilization by both producers and consumers, and show that population genotypic diversity can increase the resistance of a native plant to an invasive herbivore.

Climate conditions of the “El Niño” phenomenon for a hydro-eolic complementarity project in peru

NASA Astrophysics Data System (ADS)

Castillo N, Leonardo; Ortega M, Arturo; Luyo, Jaime E.

2018-05-01

Northern Peru is threatened by the consequences of a natural phenomenon called “El Niño”, mainly during the months of December to April. In the summer of 2017, this event reported strong climatic variations with intense rains, increasing the water levels of the Chira and Piura rivers, filling the Poechos reservoir, together with flooding and mudding. However, from an energetic perspective, these climatic alterations have a strong potential to increase the availability of the wind and hydro renewable energies in northern Peru. This work performs an evaluation of the hydro-eolic complementarity as part of the sustainability of energy systems. The study includes evaluation of historical records of wind velocity and water flow rates. It then evaluates correlation, analysis, and estimates the hydro and wind energy potentials generated by this phenomenon. The implications of the "El Niño" phenomenon are mostly negative. Nonetheless, it is possible to take advantage of higher wind and water flow rates with a hybrid energy system. The results obtained show a high degree of complementarity both normal and "El Niño" phenomenon condition in northern Peru.

Qualification of a Quantitative Method for Monitoring Aspartate Isomerization of a Monoclonal Antibody by Focused Peptide Mapping.

PubMed

Cao, Mingyan; Mo, Wenjun David; Shannon, Anthony; Wei, Ziping; Washabaugh, Michael; Cash, Patricia

Aspartate (Asp) isomerization is a common post-translational modification of recombinant therapeutic proteins that can occur during manufacturing, storage, or administration. Asp isomerization in the complementarity-determining regions of a monoclonal antibody may affect the target binding and thus a sufficiently robust quality control method for routine monitoring is desirable. In this work, we utilized a liquid chromatography-mass spectrometry (LC/MS)-based approach to identify the Asp isomerization in the complementarity-determining regions of a therapeutic monoclonal antibody. To quantitate the site-specific Asp isomerization of the monoclonal antibody, a UV detection-based quantitation assay utilizing the same LC platform was developed. The assay was qualified and implemented for routine monitoring of this product-specific modification. Compared with existing methods, this analytical paradigm is applicable to identify Asp isomerization (or other modifications) and subsequently develop a rapid, sufficiently robust quality control method for routine site-specific monitoring and quantitation to ensure product quality. This approach first identifies and locates a product-related impurity (a critical quality attribute) caused by isomerization, deamidation, oxidation, or other post-translational modifications, and then utilizes synthetic peptides and MS to assist the development of a LC-UV-based chromatographic method that separates and quantifies the product-related impurities by UV peaks. The established LC-UV method has acceptable peak specificity, precision, linearity, and accuracy; it can be validated and used in a good manufacturing practice environment for lot release and stability testing. Aspartate isomerization is a common post-translational modification of recombinant proteins during manufacture process and storage. Isomerization in the complementarity-determining regions (CDRs) of a monoclonal antibody A (mAb-A) has been detected and has been shown to have impact on the binding affinity to the antigen. In this work, we utilized a mass spectrometry-based peptide mapping approach to detect and quantitate the Asp isomerization in the CDRs of mAb-A. To routinely monitor the CDR isomerization of mAb-A, a focused peptide mapping method utilizing reversed phase chromatographic separation and UV detection has been developed and qualified. This approach is generally applicable to monitor isomerization and other post-translational modifications of proteins in a specific and high-throughput mode to ensure product quality. © PDA, Inc. 2016.

Functionally dissimilar neighbors accelerate litter decomposition in two grass species.

PubMed

Barbe, Lou; Jung, Vincent; Prinzing, Andreas; Bittebiere, Anne-Kristel; Butenschoen, Olaf; Mony, Cendrine

2017-05-01

Plant litter decomposition is a key regulator of nutrient recycling. In a given environment, decomposition of litter from a focal species depends on its litter quality and on the efficiency of local decomposers. Both may be strongly modified by functional traits of neighboring species, but the consequences for decomposition of litter from the focal species remain unknown. We tested whether decomposition of a focal plant's litter is influenced by the functional-trait dissimilarity to the neighboring plants. We cultivated two grass species (Brachypodium pinnatum and Elytrigia repens) in experimental mesocosms with functionally similar and dissimilar neighborhoods, and reciprocally transplanted litter. For both species, litter quality increased in functionally dissimilar neighborhoods, partly as a result of changes in functional traits involved in plant-plant interactions. Furthermore, functional dissimilarity increased overall decomposer efficiency in one species, probably via complementarity effects. Our results suggest a novel mechanism of biodiversity effects on ecosystem functioning in grasslands: interspecific functional diversity within plant communities can enhance intraspecific contributions to litter decomposition. Thus, plant species might better perform in diverse communities by benefiting from higher remineralization rates of their own litter. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Testing the mechanisms of diversity-dependent overyielding in a grass species.

PubMed

Atwater, Daniel Z; Callaway, Ragan M

2015-12-01

Plant diversity enhances many ecosystem processes, including productivity, but these effects have been studied almost exclusively at the taxonomic scale of species. We explore the effect of intraspecific diversity on the productivity of a widespread and dominant grassland species using accessions collected from populations throughout its range. We found that increasing population/ecotype diversity of Pseudoroegneria spicata increased productivity to a similar degree as that reported for species diversity. However, we did not find evidence that overyielding was related to either resource depletion or to pathogenic soil fungi, two causes of overyielding in species-diverse communities. Instead, larger accessions overyielded at low diversity at the expense of smaller accessions, and small accessions overyielded through complementarity at all levels of diversity. Furthermore, overyielding was stronger for accessions from mesic environments, suggesting that local adaptation might predictably influence how plants respond to increases in diversity. This suggests that mass-based competition or other cryptic accession-specific processes had complex but important effects on overyielding. Our results indicate that the effects of diversity within a species can be substantial but that overyielding by intraspecifically diverse populations may not be through the same processes thought to cause overyielding in species diverse communities.

Genomes in Turmoil: Frugality Drives Microbial Community Structure in Extremely Acidic Environments

NASA Astrophysics Data System (ADS)

Holmes, D. S.

2016-12-01

Extremely acidic environments (To gain insight into these issues, we have conducted deep bioinformatic analyses, including metabolic reconstruction of key assimilatory pathways, phylogenomics and network scrutiny of >160 genomes of acidophiles, including representatives from Archaea, Bacteria and Eukarya and at least ten metagenomes of acidic environments [Cardenas JP, et al. pp 179-197 in Acidophiles, eds R. Quatrini and D. B. Johnson, Caister Academic Press, UK (2016)]. Results yielded valuable insights into cellular processes, including carbon and nitrogen management and energy production, linking biogeochemical processes to organismal physiology. They also provided insight into the evolutionary forces that shape the genomic structure of members of acidophile communities. Niche partitioning can explain diversity patterns in rapidly changing acidic environments such as bioleaching heaps. However, in spatially and temporally homogeneous acidic environments genome flux appears to provide deeper insight into the composition and evolution of acidic consortia. Acidophiles have undergone genome streamlining by gene loss promoting mutual coexistence of species that exploit complementarity use of scarce resources consistent with the Black Queen hypothesis [Morris JJ et al. mBio 3: e00036-12 (2012)]. Acidophiles also have a large pool of accessory genes (the microbial super-genome) that can be accessed by horizontal gene transfer. This further promotes dependency relationships as drivers of community structure and the evolution of keystone species. Acknowledgements: Fondecyt 1130683; Basal CCTE PFB16

Public health developments in colonial Malaya: colonialism and the politics of prevention.

PubMed

Manderson, L

1999-01-01

In both African and Asian colonies until the late 19th century, colonial medicine operated pragmatically to meet the medical needs first of colonial officers and troops, immigrant settlers, and laborers responsible for economic development, then of indigenous populations when their ill health threatened the well-being of the expatriate population. Since the turn of the century, however, the consequences of colonial expansion and development for indigenous people's health had become increasingly apparent, and disease control and public health programs were expanded in this light. These programs increased government surveillance of populations at both community and household levels. As a consequence, colonial states extended institutional oversight and induced dependency through public health measures. Drawing on my own work on colonial Malaya, I illustrate developments in public health and their links to the moral logic of colonialism and its complementarity to the political economy.

Public health developments in colonial Malaya: colonialism and the politics of prevention.

PubMed Central

Manderson, L

1999-01-01

In both African and Asian colonies until the late 19th century, colonial medicine operated pragmatically to meet the medical needs first of colonial officers and troops, immigrant settlers, and laborers responsible for economic development, then of indigenous populations when their ill health threatened the well-being of the expatriate population. Since the turn of the century, however, the consequences of colonial expansion and development for indigenous people's health had become increasingly apparent, and disease control and public health programs were expanded in this light. These programs increased government surveillance of populations at both community and household levels. As a consequence, colonial states extended institutional oversight and induced dependency through public health measures. Drawing on my own work on colonial Malaya, I illustrate developments in public health and their links to the moral logic of colonialism and its complementarity to the political economy. PMID:9987478

Biodiversity ensures plant-pollinator phenological synchrony against climate change.

PubMed

Bartomeus, Ignasi; Park, Mia G; Gibbs, Jason; Danforth, Bryan N; Lakso, Alan N; Winfree, Rachael

2013-11-01

Climate change has the potential to alter the phenological synchrony between interacting mutualists, such as plants and their pollinators. However, high levels of biodiversity might buffer the negative effects of species-specific phenological shifts and maintain synchrony at the community level, as predicted by the biodiversity insurance hypothesis. Here, we explore how biodiversity might enhance and stabilise phenological synchrony between a valuable crop, apple and its native pollinators. We combine 46 years of data on apple flowering phenology with historical records of bee pollinators over the same period. When the key apple pollinators are considered altogether, we found extensive synchrony between bee activity and apple peak bloom due to complementarity among bee species' activity periods, and also a stable trend over time due to differential responses to warming climate among bee species. A simulation model confirms that high biodiversity levels can ensure plant-pollinator phenological synchrony and thus pollination function. © 2013 John Wiley & Sons Ltd/CNRS.

Changes in the Abundance of Grassland Species in Monocultures versus Mixtures and Their Relation to Biodiversity Effects

PubMed Central

Marquard, Elisabeth; Schmid, Bernhard; Roscher, Christiane; De Luca, Enrica; Nadrowski, Karin; Weisser, Wolfgang W.; Weigelt, Alexandra

2013-01-01

Numerous studies have reported positive effects of species richness on plant community productivity. Such biodiversity effects are usually quantified by comparing the performance of plant mixtures with reference monocultures. However, several mechanisms, such as the lack of resource complementarity and facilitation or the accumulation of detrimental agents, suggest that monocultures are more likely than mixtures to deteriorate over time. Increasing biodiversity effects over time could therefore result from declining monocultures instead of reflecting increases in the functioning of mixtures. Commonly, the latter is assumed when positive trends in biodiversity effects occur. Here, we analysed the performance of 60 grassland species growing in monocultures and mixtures over 9 years in a biodiversity experiment to clarify whether their temporal biomass dynamics differed and whether a potential decline of monocultures contributed significantly to the positive net biodiversity effect observed. Surprisingly, individual species’ populations produced, on average, significantly more biomass per unit area when growing in monoculture than when growing in mixture. Over time, productivity of species decreased at a rate that was, on average, slightly more negative in monocultures than in mixtures. The mean net biodiversity effect across all mixtures was continuously positive and ranged between 64–217 g per m2. Short-term increases in the mean net biodiversity effect were only partly due to deteriorating monocultures and were strongly affected by particular species gaining dominance in mixtures in the respective years. We conclude that our species performed, on average, comparably in monocultures and mixtures; monoculture populations being slightly more productive than mixture populations but this trend decreased over time. This suggested that negative feedbacks had not yet affected monocultures strongly but could potentially become more evident in the future. Positive biodiversity effects on aboveground productivity were heavily driven by a small, but changing, set of species that behaved differently from the average species. PMID:24098704

Changes in the abundance of grassland species in monocultures versus mixtures and their relation to biodiversity effects.

PubMed

Marquard, Elisabeth; Schmid, Bernhard; Roscher, Christiane; De Luca, Enrica; Nadrowski, Karin; Weisser, Wolfgang W; Weigelt, Alexandra

2013-01-01

Numerous studies have reported positive effects of species richness on plant community productivity. Such biodiversity effects are usually quantified by comparing the performance of plant mixtures with reference monocultures. However, several mechanisms, such as the lack of resource complementarity and facilitation or the accumulation of detrimental agents, suggest that monocultures are more likely than mixtures to deteriorate over time. Increasing biodiversity effects over time could therefore result from declining monocultures instead of reflecting increases in the functioning of mixtures. Commonly, the latter is assumed when positive trends in biodiversity effects occur. Here, we analysed the performance of 60 grassland species growing in monocultures and mixtures over 9 years in a biodiversity experiment to clarify whether their temporal biomass dynamics differed and whether a potential decline of monocultures contributed significantly to the positive net biodiversity effect observed. Surprisingly, individual species' populations produced, on average, significantly more biomass per unit area when growing in monoculture than when growing in mixture. Over time, productivity of species decreased at a rate that was, on average, slightly more negative in monocultures than in mixtures. The mean net biodiversity effect across all mixtures was continuously positive and ranged between 64-217 g per m(2). Short-term increases in the mean net biodiversity effect were only partly due to deteriorating monocultures and were strongly affected by particular species gaining dominance in mixtures in the respective years. We conclude that our species performed, on average, comparably in monocultures and mixtures; monoculture populations being slightly more productive than mixture populations but this trend decreased over time. This suggested that negative feedbacks had not yet affected monocultures strongly but could potentially become more evident in the future. Positive biodiversity effects on aboveground productivity were heavily driven by a small, but changing, set of species that behaved differently from the average species.

Effect of thiram and of a hydrocarbon mixture on freshwater macroinvertebrate communities in outdoor stream and pond mesocosms: I. Study design, chemicals fate and structural responses.

PubMed

Bayona, Yannick; Roucaute, Marc; Cailleaud, Kevin; Lagadic, Laurent; Bassères, Anne; Caquet, Thierry

2015-11-01

Higher-tier ecological risk assessment (ERA) in mesocosms is commonly performed in lotic or lentic experimental systems. These systems differ in their physico-chemical and hydrological properties, leading to differences in chemical fate, community characteristics and potential recovery. This raises the issue of the relevance and sensitivity of community-level endpoints in different types of mesocosms. In this study, macroinvertebrate abundance and biomass estimates were used to assess the effects of a dithiocarbamate fungicide, thiram (35 and 170 µg l(-1)), and a petroleum middle distillate (PMD; 0.01, 0.4, 2 and 20 mg l(-1)) in outdoor stream and pond mesocosms. Streams were continuously treated during 3 weeks followed by a 2-month long post-treatment period. Ponds were treated weekly for 4 weeks, followed by a 10-month long post-treatment period. Taxonomic structure of macroinvertebrate communities was characterized using the α, β and γ components of taxa richness, Shannon and Gini-Simpson indices. Computations were based either on abundance or biomass data. Results clearly highlighted that the effects of chemicals depended on the exposure regime (for thiram) and type of system (for the PMD). Causes of the differences between streams and ponds in the magnitude and nature of effects include differential sensitivity of taxa dwelling in lentic and lotic systems and the influence of hydrology (e.g., drift from upstream) and mesocosm connectivity on recovery dynamics. This study also showed complementarities in the use of both types of mesocosms to improve the characterization of chemical effects on communities in ERA.

Phytoplankton Diversity and Community Composition along the Estuarine Gradient of a Temperate Macrotidal Ecosystem: Combined Morphological and Molecular Approaches

PubMed Central

Bazin, Pauline; Jouenne, Fabien; Friedl, Thomas; Deton-Cabanillas, Anne-Flore; Le Roy, Bertrand; Véron, Benoît

2014-01-01

Microscopical and molecular analyses were used to investigate the diversity and spatial community structure of spring phytoplankton all along the estuarine gradient in a macrotidal ecosystem, the Baie des Veys (eastern English Channel). Taxa distribution at high tide in the water column appeared to be mainly driven by the tidal force which superimposed on the natural salinity gradient, resulting in a two-layer flow within the channel. Lowest taxa richness and abundance were found in the bay where Teleaulax-like cryptophytes dominated. A shift in species composition occurred towards the mouth of the river, with the diatom Asterionellopsis glacialis dramatically accumulating in the bottom waters of the upstream brackish reach. Small thalassiosiroid diatoms dominated the upper layer river community, where taxa richness was higher. Through the construction of partial 18S rDNA clone libraries, the microeukaryotic diversity was further explored for three samples selected along the surface salinity gradient (freshwater - brackish - marine). Clone libraries revealed a high diversity among heterotrophic and/or small-sized protists which were undetected by microscopy. Among them, a rich variety of Chrysophyceae and other lineages (e.g. novel marine stramenopiles) are reported here for the first time in this transition area. However, conventional microscopy remains more efficient in revealing the high diversity of phototrophic taxa, low in abundances but morphologically distinct, that is overlooked by the molecular approach. The differences between microscopical and molecular analyses and their limitations are discussed here, pointing out the complementarities of both approaches, for a thorough phytoplankton community description. PMID:24718653

What is complementarity?: Niels Bohr and the architecture of quantum theory

NASA Astrophysics Data System (ADS)

Plotnitsky, Arkady

2014-12-01

This article explores Bohr’s argument, advanced under the heading of ‘complementarity,’ concerning quantum phenomena and quantum mechanics, and its physical and philosophical implications. In Bohr, the term complementarity designates both a particular concept and an overall interpretation of quantum phenomena and quantum mechanics, in part grounded in this concept. While the argument of this article is primarily philosophical, it will also address, historically, the development and transformations of Bohr’s thinking, under the impact of the development of quantum theory and Bohr’s confrontation with Einstein, especially their exchange concerning the EPR experiment, proposed by Einstein, Podolsky and Rosen in 1935. Bohr’s interpretation was progressively characterized by a more radical epistemology, in its ultimate form, which was developed in the 1930s and with which I shall be especially concerned here, defined by his new concepts of phenomenon and atomicity. According to this epistemology, quantum objects are seen as indescribable and possibly even as inconceivable, and as manifesting their existence only in the effects of their interactions with measuring instruments upon those instruments, effects that define phenomena in Bohr’s sense. The absence of causality is an automatic consequence of this epistemology. I shall also consider how probability and statistics work under these epistemological conditions.

Indivisibility, Complementarity and Ontology: A Bohrian Interpretation of Quantum Mechanics

NASA Astrophysics Data System (ADS)

Roldán-Charria, Jairo

2014-12-01

The interpretation of quantum mechanics presented in this paper is inspired by two ideas that are fundamental in Bohr's writings: indivisibility and complementarity. Further basic assumptions of the proposed interpretation are completeness, universality and conceptual economy. In the interpretation, decoherence plays a fundamental role for the understanding of measurement. A general and precise conception of complementarity is proposed. It is fundamental in this interpretation to make a distinction between ontological reality, constituted by everything that does not depend at all on the collectivity of human beings, nor on their decisions or limitations, nor on their existence, and empirical reality constituted by everything that not being ontological is, however, intersubjective. According to the proposed interpretation, neither the dynamical properties, nor the constitutive properties of microsystems like mass, charge and spin, are ontological. The properties of macroscopic systems and space-time are also considered to belong to empirical reality. The acceptance of the above mentioned conclusion does not imply a total rejection of the notion of ontological reality. In the paper, utilizing the Aristotelian ideas of general cause and potentiality, a relation between ontological reality and empirical reality is proposed. Some glimpses of ontological reality, in the form of what can be said about it, are finally presented.

A linear complementarity method for the solution of vertical vehicle-track interaction

NASA Astrophysics Data System (ADS)

Zhang, Jian; Gao, Qiang; Wu, Feng; Zhong, Wan-Xie

2018-02-01

A new method is proposed for the solution of the vertical vehicle-track interaction including a separation between wheel and rail. The vehicle is modelled as a multi-body system using rigid bodies, and the track is treated as a three-layer beam model in which the rail is considered as an Euler-Bernoulli beam and both the sleepers and the ballast are represented by lumped masses. A linear complementarity formulation is directly established using a combination of the wheel-rail normal contact condition and the generalised-α method. This linear complementarity problem is solved using the Lemke algorithm, and the wheel-rail contact force can be obtained. Then the dynamic responses of the vehicle and the track are solved without iteration based on the generalised-α method. The same equations of motion for the vehicle and track are adopted at the different wheel-rail contact situations. This method can remove some restrictions, that is, time-dependent mass, damping and stiffness matrices of the coupled system, multiple equations of motion for the different contact situations and the effect of the contact stiffness. Numerical results demonstrate that the proposed method is effective for simulating the vehicle-track interaction including a separation between wheel and rail.

Emergence of complementarity and the Baconian roots of Niels Bohr's method

NASA Astrophysics Data System (ADS)

Perovic, Slobodan

2013-08-01

I argue that instead of a rather narrow focus on N. Bohr's account of complementarity as a particular and perhaps obscure metaphysical or epistemological concept (or as being motivated by such a concept), we should consider it to result from pursuing a particular method of studying physical phenomena. More precisely, I identify a strong undercurrent of Baconian method of induction in Bohr's work that likely emerged during his experimental training and practice. When its development is analyzed in light of Baconian induction, complementarity emerges as a levelheaded rather than a controversial account, carefully elicited from a comprehensive grasp of the available experimental basis, shunning hasty metaphysically motivated generalizations based on partial experimental evidence. In fact, Bohr's insistence on the "classical" nature of observations in experiments, as well as the counterintuitive synthesis of wave and particle concepts that have puzzled scholars, seem a natural outcome (an updated instance) of the inductive method. Such analysis clarifies the intricacies of early Schrödinger's critique of the account as well as Bohr's response, which have been misinterpreted in the literature. If adequate, the analysis may lend considerable support to the view that Bacon explicated the general terms of an experimentally minded strand of the scientific method, developed and refined by scientists in the following three centuries.

Reciprocal and Complementary Sibling Interactions: Relations with Socialization Outcomes in the Kindergarten Classroom

PubMed Central

Harrist, Amanda W.; Achacoso, Joseph A.; John, Aesha; Pettit, Gregory S.; Bates, John E.; Dodge, Kenneth A.

2013-01-01

Research Findings To examine associations between sibling interaction patterns and later social outcomes in single- and two-parent families, 113 kindergarteners took part in naturalistic observations at home with siblings, classmates participated in sociometric interviews, and teachers completed behavior ratings. Sibling interactions were coded using a newly-developed 39-item checklist, and proportions of complementary and reciprocal sibling interactions computed. Complementarity occurred more among dyads where kindergartners were with toddler or infant siblings than among kindergartners with older or near-age younger siblings. Higher levels of complementarity predicted lower levels of internalizing but were not related to externalizing problems. Kindergartners’ sociometric status in the classroom differed as a function of sibling interaction patterns, with neglected and controversial children experiencing less complementarity/more reciprocity than popular, average, and rejected children. Finally, there was some evidence for differential associations of sibling interaction patterns with social outcomes for children in single- versus two-parent families: regressions testing interaction effects show sibling reciprocity positively associated with kindergartners’ social skills only in single-parent families, and complementary sibling interactions positively related to internalizing problems only in two-parent families. Implications for Practice Those working with divorcing or other single-parent families might consider sibling interactions as a potential target for social skill building. PMID:26005311

Target mimicry provides a new mechanism for regulation of microRNA activity.

PubMed

Franco-Zorrilla, José Manuel; Valli, Adrián; Todesco, Marco; Mateos, Isabel; Puga, María Isabel; Rubio-Somoza, Ignacio; Leyva, Antonio; Weigel, Detlef; García, Juan Antonio; Paz-Ares, Javier

2007-08-01

MicroRNAs (miRNA) regulate key aspects of development and physiology in animals and plants. These regulatory RNAs act as guides of effector complexes to recognize specific mRNA sequences based on sequence complementarity, resulting in translational repression or site-specific cleavage. In plants, most miRNA targets are cleaved and show almost perfect complementarity with the miRNAs around the cleavage site. Here, we examined the non-protein coding gene IPS1 (INDUCED BY PHOSPHATE STARVATION 1) from Arabidopsis thaliana. IPS1 contains a motif with sequence complementarity to the phosphate (Pi) starvation-induced miRNA miR-399, but the pairing is interrupted by a mismatched loop at the expected miRNA cleavage site. We show that IPS1 RNA is not cleaved but instead sequesters miR-399. Thus, IPS1 overexpression results in increased accumulation of the miR-399 target PHO2 mRNA and, concomitantly, in reduced shoot Pi content. Engineering of IPS1 to be cleavable abolishes its inhibitory activity on miR-399. We coin the term 'target mimicry' to define this mechanism of inhibition of miRNA activity. Target mimicry can be generalized beyond the control of Pi homeostasis, as demonstrated using artificial target mimics.

Working Group Report: Dark Matter Complementarity (Dark Matter in the Coming Decade: Complementary Paths to Discovery and Beyond)

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

Arrenberg, Sebastian; et al.,

2013-10-31

In this Report we discuss the four complementary searches for the identity of dark matter: direct detection experiments that look for dark matter interacting in the lab, indirect detection experiments that connect lab signals to dark matter in our own and other galaxies, collider experiments that elucidate the particle properties of dark matter, and astrophysical probes sensitive to non-gravitational interactions of dark matter. The complementarity among the different dark matter searches is discussed qualitatively and illustrated quantitatively in several theoretical scenarios. Our primary conclusion is that the diversity of possible dark matter candidates requires a balanced program based on allmore » four of those approaches.« less

Insights to primitive replication derived from structures of small oligonucleotides

NASA Technical Reports Server (NTRS)

Smith, G. K.; Fox, G. E.

1995-01-01

Available information on the structure of small oligonucleotides is surveyed. It is observed that even small oligomers typically exhibit defined structures over a wide range of pH and temperature. These structures rely on a plethora of non-standard base-base interactions in addition to the traditional Watson-Crick pairings. Stable duplexes, though typically antiparallel, can be parallel or staggered and perfect complementarity is not essential. These results imply that primitive template directed reactions do not require high fidelity. Hence, the extensive use of Watson-Crick complementarity in genes rather than being a direct consequence of the primitive condensation process, may instead reflect subsequent selection based on the advantage of accuracy in maintaining the primitive genetic machinery once it arose.

Identifying functional cancer-specific miRNA-mRNA interactions in testicular germ cell tumor.

PubMed

Sedaghat, Nafiseh; Fathy, Mahmood; Modarressi, Mohammad Hossein; Shojaie, Ali

2016-09-07

Testicular cancer is the most common cancer in men aged between 15 and 35 and more than 90% of testicular neoplasms are originated at germ cells. Recent research has shown the impact of microRNAs (miRNAs) in different types of cancer, including testicular germ cell tumor (TGCT). MicroRNAs are small non-coding RNAs which affect the development and progression of cancer cells by binding to mRNAs and regulating their expressions. The identification of functional miRNA-mRNA interactions in cancers, i.e. those that alter the expression of genes in cancer cells, can help delineate post-regulatory mechanisms and may lead to new treatments to control the progression of cancer. A number of sequence-based methods have been developed to predict miRNA-mRNA interactions based on the complementarity of sequences. While necessary, sequence complementarity is, however, not sufficient for presence of functional interactions. Alternative methods have thus been developed to refine the sequence-based interactions using concurrent expression profiles of miRNAs and mRNAs. This study aims to find functional cancer-specific miRNA-mRNA interactions in TGCT. To this end, the sequence-based predicted interactions are first refined using an ensemble learning method, based on two well-known methods of learning miRNA-mRNA interactions, namely, TaLasso and GenMiR++. Additional functional analyses were then used to identify a subset of interactions to be most likely functional and specific to TGCT. The final list of 13 miRNA-mRNA interactions can be potential targets for identifying TGCT-specific interactions and future laboratory experiments to develop new therapies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Changes in complementarity-determining regions significantly alter IgG binding to the neonatal Fc receptor (FcRn) and pharmacokinetics

PubMed Central

King, Amy C.; Kavosi, Mania; Wang, Mengmeng; O'Hara, Denise M.; Tchistiakova, Lioudmila; Katragadda, Madan

2018-01-01

ABSTRACT A large body of data exists demonstrating that neonatal Fc receptor (FcRn) binding of an IgG via its Fc CH2-CH3 interface trends with the pharmacokinetics (PK) of IgG. We have observed that PK of IgG molecules vary widely, even when they share identical Fc domains. This led us to hypothesize that domains distal from the Fc could contribute to FcRn binding and affect PK. In this study, we explored the role of these IgG domains in altering the affinity between IgG and FcRn. Using a surface plasmon resonance-based assay developed to examine the steady-state binding affinity (KD) of IgG molecules to FcRn, we dissected the contributions of IgG domains in modulating the affinity between FcRn and IgG. Through analysis of a broad collection of therapeutic antibodies containing more than 50 unique IgG molecules, we demonstrated that variable domains, and in particular complementarity-determining regions (CDRs), significantly alter binding affinity to FcRn in vitro. Furthermore, a panel of IgG molecules differing only by 1–5 mutations in CDRs altered binding affinity to FcRn in vitro, by up to 79-fold, and the affinity values correlated with calculated isoelectric point values of both variable domains and CDR-L3. In addition, tighter affinity values trend with faster in vivo clearance of a set of IgG molecules differing only by 1–3 mutations in human FcRn transgenic mice. Understanding the role of CDRs in modulation of IgG affinity to FcRn in vitro and their effect on PK of IgG may have far-reaching implications in the optimization of IgG therapeutics. PMID:28991504

Physical Heterogeneity Increases Biofilm Resource Use and Its Molecular Diversity in Stream Mesocosms

PubMed Central

Singer, Gabriel; Besemer, Katharina; Schmitt-Kopplin, Philippe; Hödl, Iris; Battin, Tom J.

2010-01-01

Background Evidence increasingly shows that stream ecosystems greatly contribute to global carbon fluxes. This involves a tight coupling between biofilms, the dominant form of microbial life in streams, and dissolved organic carbon (DOC), a very significant pool of organic carbon on Earth. Yet, the interactions between microbial biodiversity and the molecular diversity of resource use are poorly understood. Methodology/Principal Findings Using six 40-m-long streamside flumes, we created a gradient of streambed landscapes with increasing spatial flow heterogeneity to assess how physical heterogeneity, inherent to streams, affects biofilm diversity and DOC use. We determined bacterial biodiversity in all six landscapes using 16S-rRNA fingerprinting and measured carbon uptake from glucose and DOC experimentally injected to all six flumes. The diversity of DOC molecules removed from the water was determined from ultrahigh-resolution Fourier Transform Ion Cyclotron Resonance mass spectrometry (FTICR-MS). Bacterial beta diversity, glucose and DOC uptake, and the molecular diversity of DOC use all increased with increasing flow heterogeneity. Causal modeling and path analyses of the experimental data revealed that the uptake of glucose was largely driven by physical processes related to flow heterogeneity, whereas biodiversity effects, such as complementarity, most likely contributed to the enhanced uptake of putatively recalcitrant DOC compounds in the streambeds with higher flow heterogeneity. Conclusions/Significance Our results suggest biophysical mechanisms, including hydrodynamics and microbial complementarity effects, through which physical heterogeneity induces changes of resource use and carbon fluxes in streams. These findings highlight the importance of fine-scale streambed heterogeneity for microbial biodiversity and ecosystem functioning in streams, where homogenization and loss of habitats increasingly reduce biodiversity. PMID:20376323

Antisense RNA Strategies for Metabolic Engineering of Clostridium acetobutylicum

PubMed Central

Desai, Ruchir P.; Papoutsakis, Eleftherios T.

1999-01-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by ∼100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes. PMID:10049845

Antisense RNA strategies for metabolic engineering of Clostridium acetobutylicum.

PubMed

Desai, R P; Papoutsakis, E T

1999-03-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by approximately 100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes.

Plant selection and soil legacy enhance long-term biodiversity effects.

PubMed

Zuppinger-Dingley, Debra; Flynn, Dan F B; De Deyn, Gerlinde B; Petermann, Jana S; Schmid, Bernhard

2016-04-01

Plant-plant and plant-soil interactions can help maintain plant diversity and ecosystem functions. Changes in these interactions may underlie experimentally observed increases in biodiversity effects over time via the selection of genotypes adapted to low or high plant diversity. Little is known, however, about such community-history effects and particularly the role of plant-soil interactions in this process. Soil-legacy effects may occur if co-evolved interactions with soil communities either positively or negatively modify plant biodiversity effects. We tested how plant selection and soil legacy influence biodiversity effects on productivity, and whether such effects increase the resistance of the communities to invasion by weeds. We used two plant selection treatments: parental plants growing in monoculture or in mixture over 8 yr in a grassland biodiversity experiment in the field, which we term monoculture types and mixture types. The two soil-legacy treatments used in this study were neutral soil inoculated with live or sterilized soil inocula collected from the same plots in the biodiversity experiment. For each of the four factorial combinations, seedlings of eight species were grown in monocultures or four-species mixtures in pots in an experimental garden over 15 weeks. Soil legacy (live inoculum) strongly increased biodiversity complementarity effects for communities of mixture types, and to a significantly weaker extent for communities of monoculture types. This may be attributed to negative plant-soil feedbacks suffered by mixture types in monocultures, whereas monoculture types had positive plant-soil feedbacks, in both monocultures and mixtures. Monocultures of mixture types were most strongly invaded by weeds, presumably due to increased pathogen susceptibility, reduced biomass, and altered plant-soil interactions of mixture types. These results show that biodiversity effects in experimental grassland communities can be modified by the evolution of positive vs. negative plant-soil feedbacks of plant monoculture vs. mixture types.

Applications of genetic algorithms on the structure-activity relationship analysis of some cinnamamides.

PubMed

Hou, T J; Wang, J M; Liao, N; Xu, X J

1999-01-01

Quantitative structure-activity relationships (QSARs) for 35 cinnamamides were studied. By using a genetic algorithm (GA), a group of multiple regression models with high fitness scores was generated. From the statistical analyses of the descriptors used in the evolution procedure, the principal features affecting the anticonvulsant activity were found. The significant descriptors include the partition coefficient, the molar refraction, the Hammet sigma constant of the substituents on the benzene ring, and the formation energy of the molecules. It could be found that the steric complementarity and the hydrophobic interaction between the inhibitors and the receptor were very important to the biological activity, while the contribution of the electronic effect was not so obvious. Moreover, by construction of the spline models for these four principal descriptors, the effective range for each descriptor was identified.

DISE: A Seed-Dependent RNAi Off-Target Effect That Kills Cancer Cells.

PubMed

Putzbach, William; Gao, Quan Q; Patel, Monal; Haluck-Kangas, Ashley; Murmann, Andrea E; Peter, Marcus E

2018-01-01

Off-target effects (OTEs) represent a significant caveat for RNAi caused by substantial complementarity between siRNAs and unintended mRNAs. We now discuss the existence of three types of seed-dependent OTEs (sOTEs). Type I involves unintended targeting through the guide strand seed of an siRNA. Type II is caused by the activity of the seed on the designated siRNA passenger strand when loaded into the RNA-induced silencing complex (RISC). Both type I and II sOTEs will elicit unpredictable cellular responses. By contrast, in sOTE type III the guide strand seed preferentially targets essential survival genes resulting in death induced by survival gene elimination (DISE). In this Opinion article, we discuss DISE as a consequence of RNAi that may preferentially affect cancer cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Impact of Empire Expansion on Household Diet: The Inka in Northern Chile's Atacama Desert

PubMed Central

Vinton, Sheila Dorsey; Perry, Linda; Reinhard, Karl J.; Santoro, Calogero M.; Teixeira-Santos, Isabel

2009-01-01

The impact of expanding civilization on the health of American indigenous societies has long been studied. Most studies have focused on infections and malnutrition that occurred when less complex societies were incorporated into more complex civilizations. The details of dietary change, however, have rarely been explored. Using the analysis of starch residues recovered from coprolites, here we evaluate the dietary adaptations of indigenous farmers in northern Chile's Atacama Desert during the time that the Inka Empire incorporated these communities into their economic system. This system has been described as “complementarity” because it involves interaction and trade in goods produced at different Andean elevations. We find that as local farming societies adapted to this new asymmetric system, a portion of their labor had to be given up to the Inka elite through a corvée tax system for maize production. In return, the Inka system of complementarity introduced previously rare foods from the Andean highlands into local economies. These changes caused a disruption of traditional communities as they instituted a state-level economic system on local farmers. Combined with previously published infection information for the same populations under Inka rule, the data suggest that there may have been a dual health impact from disruption of nutrition and introduction of crowd disease. PMID:19956668

Resource Availability Alters Biodiversity Effects in Experimental Grass-Forb Mixtures.

PubMed

Siebenkäs, Alrun; Schumacher, Jens; Roscher, Christiane

2016-01-01

Numerous experiments, mostly performed in particular environments, have shown positive diversity-productivity relationships. Although the complementary use of resources is discussed as an important mechanism explaining diversity effects, less is known about how resource availability controls the strength of diversity effects and how this response depends on the functional composition of plant communities. We studied aboveground biomass production in experimental monocultures, two- and four-species mixtures assembled from two independent pools of four perennial grassland species, each representing two functional groups (grasses, forbs) and two growth statures (small, tall), and exposed to different combinations of light and nutrient availability. On average, shade led to a decrease in aboveground biomass production of 24% while fertilization increased biomass production by 36%. Mixtures were on average more productive than expected from their monocultures (relative yield total, RYT>1) and showed positive net diversity effects (NE: +34% biomass increase; mixture minus mean monoculture biomass). Both trait-independent complementarity effects (TICE: +21%) and dominance effects (DE: +12%) positively contributed to net diversity effects, while trait-dependent complementarity effects were minor (TDCE: +1%). Shading did not alter diversity effects and overyielding. Fertilization decreased RYT and the proportion of biomass gain through TICE and TDCE, while DE increased. Diversity effects did not increase with species richness and were independent of functional group or growth stature composition. Trait-based analyses showed that the dominance of species with root and leaf traits related to resource conservation increased TICE. Traits indicating the tolerance of shade showed positive relationships with TDCE. Large DE were associated with the dominance of species with tall growth and low diversity in leaf nitrogen concentrations. Our field experiment shows that positive diversity effects are possible in grass-forb mixtures irrespective of differences in light availability, but that the chance for the complementary use of resources increases when nutrients are not available at excess.

Resource Availability Alters Biodiversity Effects in Experimental Grass-Forb Mixtures

PubMed Central

Siebenkäs, Alrun; Schumacher, Jens; Roscher, Christiane

2016-01-01

Numerous experiments, mostly performed in particular environments, have shown positive diversity-productivity relationships. Although the complementary use of resources is discussed as an important mechanism explaining diversity effects, less is known about how resource availability controls the strength of diversity effects and how this response depends on the functional composition of plant communities. We studied aboveground biomass production in experimental monocultures, two- and four-species mixtures assembled from two independent pools of four perennial grassland species, each representing two functional groups (grasses, forbs) and two growth statures (small, tall), and exposed to different combinations of light and nutrient availability. On average, shade led to a decrease in aboveground biomass production of 24% while fertilization increased biomass production by 36%. Mixtures were on average more productive than expected from their monocultures (relative yield total, RYT>1) and showed positive net diversity effects (NE: +34% biomass increase; mixture minus mean monoculture biomass). Both trait-independent complementarity effects (TICE: +21%) and dominance effects (DE: +12%) positively contributed to net diversity effects, while trait-dependent complementarity effects were minor (TDCE: +1%). Shading did not alter diversity effects and overyielding. Fertilization decreased RYT and the proportion of biomass gain through TICE and TDCE, while DE increased. Diversity effects did not increase with species richness and were independent of functional group or growth stature composition. Trait-based analyses showed that the dominance of species with root and leaf traits related to resource conservation increased TICE. Traits indicating the tolerance of shade showed positive relationships with TDCE. Large DE were associated with the dominance of species with tall growth and low diversity in leaf nitrogen concentrations. Our field experiment shows that positive diversity effects are possible in grass-forb mixtures irrespective of differences in light availability, but that the chance for the complementary use of resources increases when nutrients are not available at excess. PMID:27341495

Complementarity in Spontaneous Emission: Quantum Jumps, Staggers and Slides

NASA Astrophysics Data System (ADS)

Wiseman, H.

Dan Walls is rightly famous for his part in many of the outstanding developments in quantum optics in the last 30 years. Two of these are most relevant to this paper. The first is the prediction of nonclassical properties of the fluorescence of a two-level atom, such as antibunching [1] and squeezing [2]. Both of these predictions have now been verified experimentally [3,4]. The second is the investigation of fundamental issues such as complementarity and the uncertainty principle [5,6]. This latter area is one which has generated a lively theoretical discussion [7], and, more importantly, suggested new experiments [8]. It was also an area in which I had the honour of working with Dan [9], and of gaining the benefit of his instinct for picking a fruitful line of investigation.

Black hole complementarity in gravity's rainbow

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

Gim, Yongwan; Kim, Wontae, E-mail: yongwan89@sogang.ac.kr, E-mail: wtkim@sogang.ac.kr

2015-05-01

To see how the gravity's rainbow works for black hole complementary, we evaluate the required energy for duplication of information in the context of black hole complementarity by calculating the critical value of the rainbow parameter in the certain class of the rainbow Schwarzschild black hole. The resultant energy can be written as the well-defined limit for the vanishing rainbow parameter which characterizes the deformation of the relativistic dispersion relation in the freely falling frame. It shows that the duplication of information in quantum mechanics could not be allowed below a certain critical value of the rainbow parameter; however, itmore » might be possible above the critical value of the rainbow parameter, so that the consistent formulation in our model requires additional constraints or any other resolutions for the latter case.« less

Linear complementarity formulation for 3D frictional sliding problems

USGS Publications Warehouse

Kaven, Joern; Hickman, Stephen H.; Davatzes, Nicholas C.; Mutlu, Ovunc

2012-01-01

Frictional sliding on quasi-statically deforming faults and fractures can be modeled efficiently using a linear complementarity formulation. We review the formulation in two dimensions and expand the formulation to three-dimensional problems including problems of orthotropic friction. This formulation accurately reproduces analytical solutions to static Coulomb friction sliding problems. The formulation accounts for opening displacements that can occur near regions of non-planarity even under large confining pressures. Such problems are difficult to solve owing to the coupling of relative displacements and tractions; thus, many geomechanical problems tend to neglect these effects. Simple test cases highlight the importance of including friction and allowing for opening when solving quasi-static fault mechanics models. These results also underscore the importance of considering the effects of non-planarity in modeling processes associated with crustal faulting.

Seasonal changes in the assembly mechanisms structuring tropical fish communities.

PubMed

Fitzgerald, Daniel B; Winemiller, Kirk O; Sabaj Pérez, Mark H; Sousa, Leandro M

2017-01-01

Despite growing interest in trait-based approaches to community assembly, little attention has been given to seasonal variation in trait distribution patterns. Mobile animals can rapidly mediate influences of environmental factors and species interactions through dispersal, suggesting that the relative importance of different assembly mechanisms can vary over short time scales. This study analyzes seasonal changes in functional trait distributions of tropical fishes in the Xingu River, a major tributary of the Amazon with large predictable temporal variation in hydrologic conditions and species density. Comparison of observed functional diversity revealed that species within wet-season assemblages were more functionally similar than those in dry-season assemblages. Further, species within wet-season assemblages were more similar than random expectations based on null model predictions. Higher functional richness within dry season communities is consistent with increased niche complementarity during the period when fish densities are highest and biotic interactions should be stronger; however, null model tests suggest that stochastic factors or a combination of assembly mechanisms influence dry-season assemblages. These results demonstrate that the relative influence of community assembly mechanisms can vary seasonally in response to changing abiotic conditions, and suggest that studies attempting to infer a single dominant mechanism from functional patterns may overlook important aspects of the assembly process. During the prolonged flood pulse of the wet season, expanded habitat and lower densities of aquatic organisms likely reduce the influence of competition and predation. This temporal shift in the influence of different assembly mechanisms, rather than any single mechanism, may play a large role in maintaining the structure and diversity of tropical rivers and perhaps other dynamic and biodiverse systems. © 2016 by the Ecological Society of America.

Modeling plant composition as community continua in a forest landscape with LiDAR and hyperspectral remote sensing.

PubMed

Hakkenberg, C R; Peet, R K; Urban, D L; Song, C

2018-01-01

In light of the need to operationalize the mapping of forest composition at landscape scales, this study uses multi-scale nested vegetation sampling in conjunction with LiDAR-hyperspectral remotely sensed data from the G-LiHT airborne sensor to map vascular plant compositional turnover in a compositionally and structurally complex North Carolina Piedmont forest. Reflecting a shift in emphasis from remotely sensing individual crowns to detecting aggregate optical-structural properties of forest stands, predictive maps reflect the composition of entire vascular plant communities, inclusive of those species smaller than the resolution of the remotely sensed imagery, intertwined with proximate taxa, or otherwise obscured from optical sensors by dense upper canopies. Stand-scale vascular plant composition is modeled as community continua: where discrete community-unit classes at different compositional resolutions provide interpretable context for continuous gradient maps that depict n-dimensional compositional complexity as a single, consistent RGB color combination. In total, derived remotely sensed predictors explain 71%, 54%, and 48% of the variation in the first three components of vascular plant composition, respectively. Among all remotely sensed environmental gradients, topography derived from LiDAR ground returns, forest structure estimated from LiDAR all returns, and morphological-biochemical traits determined from hyperspectral imagery each significantly correspond to the three primary axes of floristic composition in the study site. Results confirm the complementarity of LiDAR and hyperspectral sensors for modeling the environmental gradients constraining landscape turnover in vascular plant composition and hold promise for predictive mapping applications spanning local land management to global ecosystem modeling. © 2017 by the Ecological Society of America.

A scientific program for infrared, submillimeter and radio astronomy from space: A report by the Management Operations Working Group

NASA Technical Reports Server (NTRS)

1989-01-01

Important and fundamental scientific progress can be attained through space observations in the wavelengths longward of 1 micron. The formation of galaxies, stars, and planets, the origin of quasars and the nature of active galactic nuclei, the large scale structure of the Universe, and the problem of the missing mass, are among the major scientific issues that can be addressed by these observations. Significant advances in many areas of astrophysics can be made over the next 20 years by implementing the outlined program. This program combines large observatories with smaller projects to create an overall scheme that emphasized complementarity and synergy, advanced technology, community support and development, and the training of the next generation of scientists. Key aspects of the program include: the Space Infrared Telescope Facility; the Stratospheric Observatory for Infrared Astronomy; a robust program of small missions; and the creation of the technology base for future major observatories.

HELCOM Baltic Sea Action Plan--a regional programme of measures for the marine environment based on the Ecosystem Approach.

PubMed

Backer, Hermanni; Leppänen, Juha-Markku; Brusendorff, Anne Christine; Forsius, Kaj; Stankiewicz, Monika; Mehtonen, Jukka; Pyhälä, Minna; Laamanen, Maria; Paulomäki, Hanna; Vlasov, Nikolay; Haaranen, Tarja

2010-05-01

The Helsinki Commission (HELCOM) Baltic Sea Action Plan, adopted by the coastal countries of the Baltic Sea and the European Community in November 2007, is a regional intergovernmental programme of measures for the protection and management of the marine environment explicitly based on the Ecosystem Approach. The Action Plan is structured around a set of Ecological Objectives used to define indicators and targets, including effect-based nutrient input ceilings, and to monitor implementation. The Action Plan strongly links Baltic marine environmental concerns to important socio-economic fields such as agriculture and fisheries and promotes cross-sectoral tools including marine spatial planning. Due to complementarities with the European Union (EU) Marine Strategy Framework Directive, the Action Plan is in essence a pilot for this process without neglecting the important role of the Russian Federation - the only Baltic coastal country not a member of the EU. (c) 2009 Elsevier Ltd. All rights reserved.

Reducing greenhouse gas emissions and adapting agricultural management for climate change in developing countries: providing the basis for action.

PubMed

Ogle, Stephen M; Olander, Lydia; Wollenberg, Lini; Rosenstock, Todd; Tubiello, Francesco; Paustian, Keith; Buendia, Leandro; Nihart, Alison; Smith, Pete

2014-01-01

Agriculture in developing countries has attracted increasing attention in international negotiations within the United Nations Framework Convention on Climate Change for both adaptation to climate change and greenhouse gas mitigation. However, there is limited understanding about potential complementarity between management practices that promote adaptation and mitigation, and limited basis to account for greenhouse gas emission reductions in this sector. The good news is that the global research community could provide the support needed to address these issues through further research linking adaptation and mitigation. In addition, a small shift in strategy by the Intergovernmental Panel on Climate Change (IPCC) and ongoing assistance from agricultural organizations could produce a framework to move the research and development from concept to reality. In turn, significant progress is possible in the near term providing the basis for UNFCCC negotiations to move beyond discussion to action for the agricultural sector in developing countries. © 2013 John Wiley & Sons Ltd.

Quantification of in vivo site-specific Asp isomerization and Asn deamidation of mAbs in animal serum using IP-LC-MS.

PubMed

Mehl, John T; Sleczka, Bogdan G; Ciccimaro, Eugene F; Kozhich, Alexander T; Gilbertson, Deb G; Vuppugalla, Ragini; Huang, Christine S; Stevens, Brenda; Mo, Jingjie; Deyanova, Ekaterina G; Wang, Yun; Huang, Richard Yc; Chen, Guodong; Olah, Timothy V

2016-08-01

Isomerization of aspartic acid and deamidation of asparagine are two common amino acid modifications that are of particular concern if located within the complementarity-determining region of therapeutic antibodies. Questions arise as to the extent of modification occurring in circulation due to potential exposure of the therapeutic antibody to different pH regimes. To enable evaluation of site-specific isomerization and deamidation of human mAbs in vivo, immunoprecipitation (IP) has been combined with LC-MS providing selective enrichment, separation and detection of naive and modified forms of tryptic peptides comprising complementarity-determining region sequences. IP-LC-MS can be applied to simultaneously quantify in vivo drug concentrations and measure the extent of isomerization or deamidation in PK studies conducted during the drug discovery stage.

A wave function for stock market returns

NASA Astrophysics Data System (ADS)

Ataullah, Ali; Davidson, Ian; Tippett, Mark

2009-02-01

The instantaneous return on the Financial Times-Stock Exchange (FTSE) All Share Index is viewed as a frictionless particle moving in a one-dimensional square well but where there is a non-trivial probability of the particle tunneling into the well’s retaining walls. Our analysis demonstrates how the complementarity principle from quantum mechanics applies to stock market prices and of how the wave function presented by it leads to a probability density which exhibits strong compatibility with returns earned on the FTSE All Share Index. In particular, our analysis shows that the probability density for stock market returns is highly leptokurtic with slight (though not significant) negative skewness. Moreover, the moments of the probability density determined under the complementarity principle employed here are all convergent - in contrast to many of the probability density functions on which the received theory of finance is based.

"It's best not to think about it at all-like the new taxes": Reality, observer, and complementarity in Bohr and Pauli

NASA Astrophysics Data System (ADS)

Plotnitsky, Arkady

2012-12-01

This article considers the concepts of reality, observer, and complementarity in Pauli and Bohr, and the similarities and, especially, differences in their understanding of these concepts, differences defined most essentially by their respective views of the role of the human observer in quantum measurement. These differences are significant even in the case of their respective interpretations of quantum phenomena and quantum mechanics, where the influence of Bohr's ideas on Pauli's understanding of quantum physics is particularly strong. They become especially strong and even radical in the case of their overall philosophical visions, where the impact of Jungean psychology, coupled to that of the earlier archetypal thinking of such figures as Kepler and Fludd, drives Pauli's thinking ever further away from that of Bohr.

Accelerator and reactor complementarity in coherent neutrino-nucleus scattering

NASA Astrophysics Data System (ADS)

Dent, James B.; Dutta, Bhaskar; Liao, Shu; Newstead, Jayden L.; Strigari, Louis E.; Walker, Joel W.

2018-02-01

We study the complementarity between accelerator and reactor coherent elastic neutrino-nucleus elastic scattering (CE ν NS ) experiments for constraining new physics in the form of nonstandard neutrino interactions (NSI). First, considering just data from the recent observation by the Coherent experiment, we explore interpretive degeneracies that emerge when activating either two or four unknown NSI parameters. Next, we demonstrate that simultaneous treatment of reactor and accelerator experiments, each employing at least two distinct target materials, can break a degeneracy between up and down flavor-diagonal NSI terms that survives analysis of neutrino oscillation experiments. Considering four flavor-diagonal (e e /μ μ ) up- and down-type NSI parameters, we find that all terms can be measured with high local precision (to a width as small as ˜5 % in Fermi units) by next-generation experiments, although discrete reflection ambiguities persist.

The Coach-Athlete Relationship Questionnaire (CART-Q): development and initial validation.

PubMed

Jowett, Sophia; Ntoumanis, Nikos

2004-08-01

The purpose of the present study was to develop and validate a self-report instrument that measures the nature of the coach-athlete relationship. Jowett et al.'s (Jowett & Meek, 2000; Jowett, in press) qualitative case studies and relevant literature were used to generate items for an instrument that measures affective, cognitive, and behavioral aspects of the coach-athlete relationship. Two studies were carried out in an attempt to assess content, predictive, and construct validity, as well as internal consistency, of the Coach-Athlete Relationship Questionnaire (CART-Q), using two independent British samples. Principal component analysis and confirmatory factor analysis were used to reduce the number of items, identify principal components, and confirm the latent structure of the CART-Q. Results supported the multidimensional nature of the coach-athlete relationship. The latent structure of the CART-Q was underlined by the latent variables of coaches' and athletes' Closeness (emotions), Commitment (cognitions), and Complementarity (behaviors).

An evolutionary conserved pattern of 18S rRNA sequence complementarity to mRNA 5′ UTRs and its implications for eukaryotic gene translation regulation

PubMed Central

Pánek, Josef; Kolář, Michal; Vohradský, Jiří; Shivaya Valášek, Leoš

2013-01-01

There are several key mechanisms regulating eukaryotic gene expression at the level of protein synthesis. Interestingly, the least explored mechanisms of translational control are those that involve the translating ribosome per se, mediated for example via predicted interactions between the ribosomal RNAs (rRNAs) and mRNAs. Here, we took advantage of robustly growing large-scale data sets of mRNA sequences for numerous organisms, solved ribosomal structures and computational power to computationally explore the mRNA–rRNA complementarity that is statistically significant across the species. Our predictions reveal highly specific sequence complementarity of 18S rRNA sequences with mRNA 5′ untranslated regions (UTRs) forming a well-defined 3D pattern on the rRNA sequence of the 40S subunit. Broader evolutionary conservation of this pattern may imply that 5′ UTRs of eukaryotic mRNAs, which have already emerged from the mRNA-binding channel, may contact several complementary spots on 18S rRNA situated near the exit of the mRNA binding channel and on the middle-to-lower body of the solvent-exposed 40S ribosome including its left foot. We discuss physiological significance of this structurally conserved pattern and, in the context of previously published experimental results, propose that it modulates scanning of the 40S subunit through 5′ UTRs of mRNAs. PMID:23804757

Rescuing complementarity with little drama

NASA Astrophysics Data System (ADS)

Bao, Ning; Bouland, Adam; Chatwin-Davies, Aidan; Pollack, Jason; Yuen, Henry

2016-12-01

The AMPS paradox challenges black hole complementarity by apparently constructing a way for an observer to bring information from the outside of the black hole into its interior if there is no drama at its horizon, making manifest a violation of monogamy of entanglement. We propose a new resolution to the paradox: this violation cannot be explicitly checked by an infalling observer in the finite proper time they have to live after crossing the horizon. Our resolution depends on a weak relaxation of the no-drama condition (we call it "little-drama") which is the "complementarity dual" of scrambling of information on the stretched horizon. When translated to the description of the black hole interior, this implies that the fine-grained quantum information of infalling matter is rapidly diffused across the entire interior while classical observables and coarse-grained geometry remain unaffected. Under the assumption that information has diffused throughout the interior, we consider the difficulty of the information-theoretic task that an observer must perform after crossing the event horizon of a Schwarzschild black hole in order to verify a violation of monogamy of entanglement. We find that the time required to complete a necessary subroutine of this task, namely the decoding of Bell pairs from the interior and the late radiation, takes longer than the maximum amount of time that an observer can spend inside the black hole before hitting the singularity. Therefore, an infalling observer cannot observe monogamy violation before encountering the singularity.

AVC: Selecting discriminative features on basis of AUC by maximizing variable complementarity.

PubMed

Sun, Lei; Wang, Jun; Wei, Jinmao

2017-03-14

The Receiver Operator Characteristic (ROC) curve is well-known in evaluating classification performance in biomedical field. Owing to its superiority in dealing with imbalanced and cost-sensitive data, the ROC curve has been exploited as a popular metric to evaluate and find out disease-related genes (features). The existing ROC-based feature selection approaches are simple and effective in evaluating individual features. However, these approaches may fail to find real target feature subset due to their lack of effective means to reduce the redundancy between features, which is essential in machine learning. In this paper, we propose to assess feature complementarity by a trick of measuring the distances between the misclassified instances and their nearest misses on the dimensions of pairwise features. If a misclassified instance and its nearest miss on one feature dimension are far apart on another feature dimension, the two features are regarded as complementary to each other. Subsequently, we propose a novel filter feature selection approach on the basis of the ROC analysis. The new approach employs an efficient heuristic search strategy to select optimal features with highest complementarities. The experimental results on a broad range of microarray data sets validate that the classifiers built on the feature subset selected by our approach can get the minimal balanced error rate with a small amount of significant features. Compared with other ROC-based feature selection approaches, our new approach can select fewer features and effectively improve the classification performance.

Rescuing complementarity with little drama

DOE PAGES

Bao, Ning; Bouland, Adam; Chatwin-Davies, Aidan; ...

2016-12-07

The AMPS paradox challenges black hole complementarity by apparently constructing a way for an observer to bring information from the outside of the black hole into its interior if there is no drama at its horizon, making manifest a violation of monogamy of entanglement. We propose a new resolution to the paradox: this violation cannot be explicitly checked by an infalling observer in the finite proper time they have to live after crossing the horizon. Our resolution depends on a weak relaxation of the no-drama condition (we call it “little-drama”) which is the “complementarity dual” of scrambling of information onmore » the stretched horizon. When translated to the description of the black hole interior, this implies that the fine-grained quantum information of infalling matter is rapidly diffused across the entire interior while classical observables and coarse-grained geometry remain unaffected. Under the assumption that information has diffused throughout the interior, we consider the difficulty of the information-theoretic task that an observer must perform after crossing the event horizon of a Schwarzschild black hole in order to verify a violation of monogamy of entanglement. We find that the time required to complete a necessary subroutine of this task, namely the decoding of Bell pairs from the interior and the late radiation, takes longer than the maximum amount of time that an observer can spend inside the black hole before hitting the singularity. Furthermore, an infalling observer cannot observe monogamy violation before encountering the singularity.« less

Categorizing the telehealth policy response of countries and their implications for complementarity of telehealth policy.

PubMed

Varghese, Sunil; Scott, Richard E

2004-01-01

Developing countries are exploring the role of telehealth to overcome the challenges of providing adequate health care services. However, this process faces disparities, and no complementarity in telehealth policy development. Telehealth has the potential to transcend geopolitical boundaries, yet telehealth policy developed in one jurisdiction may hamper applications in another. Understanding such policy complexities is essential for telehealth to realize its full global potential. This study investigated 12 East Asian countries that may represent a microcosm of the world, to determine if the telehealth policy response of countries could be categorized, and whether any implications could be identified for the development of complementary telehealth policy. The countries were Cambodia, China, Hong Kong, Indonesia, Japan, Malaysia, Myanmar, Singapore, South Korea, Taiwan, Thailand, and Vietnam. Three categories of country response were identified in regard to national policy support and development. The first category was "None" (Cambodia, Myanmar, and Vietnam) where international partners, driven by humanitarian concerns, lead telehealth activity. The second category was "Proactive" (China, Indonesia, Malaysia, Singapore, South Korea, Taiwan, and Thailand) where national policies were designed with the view that telehealth initiatives are a component of larger development objectives. The third was "Reactive" (Hong Kong and Japan), where policies were only proffered after telehealth activities were sustainable. It is concluded that although complementarity of telehealth policy development is not occurring, increased interjurisdictional telehealth activity, regional clusters, and concerted and coordinated effort amongst researchers, practitioners, and policy makers may alter this trend.

Floral resource availability from groundcover promotes bee abundance in coffee agroecosystems.

PubMed

Fisher, Kaleigh; Gonthier, David J; Ennis, Katherine K; Perfecto, Ivette

2017-09-01

Patterns of bee abundance and diversity across different spatial scales have received thorough research consideration. However, the impact of short- and long-term temporal resource availability on biodiversity has been less explored. This is highly relevant in tropical agricultural systems for pollinators, as many foraging periods of pollinators extend beyond flowering of any single crop species. In this study, we sought to understand how bee communities in tropical agroecosystems changed between seasons, and if short- and long-term floral resource availability influenced their diversity and abundance. We used a threshold analysis approach in order to explore this relationship at two time scales. This study took place in a region dominated by coffee agroecosystems in Southern Mexico. This was an ideal system because the landscape offers a range of coffee management regimes that maintain heterogeneity in floral resource availability spatially and temporally. We found that the bee community varies significantly between seasons. There were higher abundances of native social, solitary and managed honey bees during the dry season when coffee flowers. Additionally, we found that floral resources from groundcover, but not trees, were associated with bee abundance. Further, the temporal scale of the availability of these resources is important, whereby short-term floral resource availability appears particularly important in maintaining high bee abundance at sites with lower seasonal complementarity. We argue that in addition to spatial resource heterogeneity, temporal resource heterogeneity is critical in explaining bee community patterns, and should thus be considered to promote pollinator conservation. © 2017 by the Ecological Society of America.

The Impact of Public Health Awareness Campaigns on the Awareness and Quality of Palliative Care.

PubMed

Seymour, Jane

2018-01-01

The right to health includes a right of access to good quality palliative care, but inequalities persist. Raising awareness is a key plank of the public health approach to palliative care, but involves consideration of subjects most of us prefer not to address. This review addresses the question: "do public health awareness campaigns effectively improve the awareness and quality of palliative care"? The evidence shows that public awareness campaigns can improve awareness of palliative care and probably improve quality of care, but there is a lack of evidence about the latter. Rapid review and synthesis. A comprehensive public awareness campaign about palliative care (including advance care planning and end-of-life decision making) should be based on clear and shared terminology, use well piloted materials, and the full range of mass media to suit different ages, cultures, and religious/spiritual perspectives. Arts and humanities have a role to play in allowing individuals and communities to express experiences of illness, death, and grief and encourage conversation and thoughtful reflection. There is evidence about key factors for success: targeting, networking, and use of specific, measurable, achievable, realistic time-bound objectives; continuous evaluation; and complementarity to national and international policy. Campaigns should be located within the framework of public health promotion and the synergy between short national mass media campaigns and longer term local community action initiatives carefully considered. National and local projects to raise awareness should identify and address any barriers at the level of individuals, communities, and systems of care, for example, literacy skills and unequal access to resources.

Advances in pollination ecology from tropical plantation crops.

PubMed

Klein, Alexandra-Maria; Cunningham, Saul A; Bos, Merijn; Steffan-Dewenter, Ingolf

2008-04-01

Although ecologists traditionally focus on natural ecosystems, there is growing awareness that mixed landscapes of managed and unmanaged systems provide a research environment for understanding basic ecological relationships on a large scale. Here, we show how tropical agroforestry systems can be used to develop ideas about the mechanisms that influence species diversity and subsequent biotic interactions at different spatial scales. Our focus is on tropical plantation crops, mainly coffee and cacao, and their pollinators, which are of basic ecological interest as partners in an important mutualistic interaction. We review how insect-mediated pollination services depend on local agroforest and natural habitats in surrounding landscapes. Further, we evaluate the functional significance of pollinator diversity and the explanatory value of species traits, and we provide an intercontinental comparison of pollinator assemblages. We found that optimal pollination success might be best understood as a consequence of niche complementarities among pollinators in landscapes harboring various species. We further show that small cavity-nesting bees and small generalist beetles were especially affected by isolation from forest and that larger-bodied insects in the same landscapes were not similarly affected. We suggest that mixed tropical landscapes with agroforestry systems have great potential for future research on the interactions between plants and pollinators.

Complementarity of information and the emergence of the classical world

NASA Astrophysics Data System (ADS)

Zwolak, Michael; Zurek, Wojciech

2013-03-01

We prove an anti-symmetry property relating accessible information about a system through some auxiliary system F and the quantum discord with respect to a complementary system F'. In Quantum Darwinism, where fragments of the environment relay information to observers - this relation allows us to understand some fundamental properties regarding correlations between a quantum system and its environment. First, it relies on a natural separation of accessible information and quantum information about a system. Under decoherence, this separation shows that accessible information is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. Second, It shows that objective information becomes accessible to many observers only when quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. The resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality, and supports Bohr's intuition that quantum phenomena acquire classical reality only when communicated.

de Sitter space as a tensor network: Cosmic no-hair, complementarity, and complexity

NASA Astrophysics Data System (ADS)

Bao, Ning; Cao, ChunJun; Carroll, Sean M.; Chatwin-Davies, Aidan

2017-12-01

We investigate the proposed connection between de Sitter spacetime and the multiscale entanglement renormalization ansatz (MERA) tensor network, and ask what can be learned via such a construction. We show that the quantum state obeys a cosmic no-hair theorem: the reduced density operator describing a causal patch of the MERA asymptotes to a fixed point of a quantum channel, just as spacetimes with a positive cosmological constant asymptote to de Sitter space. The MERA is potentially compatible with a weak form of complementarity (local physics only describes single patches at a time, but the overall Hilbert space is infinite dimensional) or, with certain specific modifications to the tensor structure, a strong form (the entire theory describes only a single patch plus its horizon, in a finite-dimensional Hilbert space). We also suggest that de Sitter evolution has an interpretation in terms of circuit complexity, as has been conjectured for anti-de Sitter space.

Theory of Excitonic Delocalization for Robust Vibronic Dynamics in LH2.

PubMed

Caycedo-Soler, Felipe; Lim, James; Oviedo-Casado, Santiago; van Hulst, Niek F; Huelga, Susana F; Plenio, Martin B

2018-06-11

Nonlinear spectroscopy has revealed long-lasting oscillations in the optical response of a variety of photosynthetic complexes. Different theoretical models that involve the coherent coupling of electronic (excitonic) or electronic-vibrational (vibronic) degrees of freedom have been put forward to explain these observations. The ensuing debate concerning the relevance of either mechanism may have obscured their complementarity. To illustrate this balance, we quantify how the excitonic delocalization in the LH2 unit of Rhodopseudomonas acidophila purple bacterium leads to correlations of excitonic energy fluctuations, relevant coherent vibronic coupling, and importantly, a decrease in the excitonic dephasing rates. Combining these effects, we identify a feasible origin for the long-lasting oscillations observed in fluorescent traces from time-delayed two-pulse single-molecule experiments performed on this photosynthetic complex and use this approach to discuss the role of this complementarity in other photosynthetic systems.

Complementarity of quantum discord and classically accessible information

DOE PAGES

Zwolak, Michael P.; Zurek, Wojciech H.

2013-05-20

The sum of the Holevo quantity (that bounds the capacity of quantum channels to transmit classical information about an observable) and the quantum discord (a measure of the quantumness of correlations of that observable) yields an observable-independent total given by the quantum mutual information. This split naturally delineates information about quantum systems accessible to observers – information that is redundantly transmitted by the environment – while showing that it is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. In addition, we prove an anti-symmetry property relating accessible information and discord. Itmore » shows that information becomes objective – accessible to many observers – only as quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. Lastly, the resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality while flagrantly quantum superpositions are out of reach.« less

Power Moves Beyond Complementarity: A Staring Look Elicits Avoidance in Low Power Perceivers and Approach in High Power Perceivers

PubMed Central

Weick, Mario; McCall, Cade; Blascovich, Jim

2017-01-01

Sustained, direct eye-gaze—staring—is a powerful cue that elicits strong responses in many primate and nonprimate species. The present research examined whether fleeting experiences of high and low power alter individuals’ spontaneous responses to the staring gaze of an onlooker. We report two experimental studies showing that sustained, direct gaze elicits spontaneous avoidance tendencies in low power perceivers and spontaneous approach tendencies in high power perceivers. These effects emerged during interactions with different targets and when power was manipulated between-individuals (Study 1) and within-individuals (Study 2), thus attesting to a high degree of flexibility in perceivers’ reactions to gaze cues. Together, the present findings indicate that power can break the cycle of complementarity in individuals’ spontaneous responding: Low power perceivers complement and move away from, and high power perceivers reciprocate and move toward, staring onlookers. PMID:28903712

Extended Minus-Strand DNA as Template for R-U5-Mediated Second-Strand Transfer in Recombinational Rescue of Primer Binding Site-Modified Retroviral Vectors

PubMed Central

Mikkelsen, Jacob Giehm; Lund, Anders H.; Dybkær, Karen; Duch, Mogens; Pedersen, Finn Skou

1998-01-01

We have previously demonstrated recombinational rescue of primer binding site (PBS)-impaired Akv murine leukemia virus-based vectors involving initial priming on endogenous viral sequences and template switching during cDNA synthesis to obtain PBS complementarity in second-strand transfer of reverse transcription (Mikkelsen et al., J. Virol. 70:1439–1447, 1996). By use of the same forced recombination system, we have now found recombinant proviruses of different structures, suggesting that PBS knockout vectors may be rescued through initial priming on endogenous virus RNA, read-through of the mutated PBS during minus-strand synthesis, and subsequent second-strand transfer mediated by the R-U5 complementarity of the plus strand and the extended minus-strand DNA acceptor template. Mechanisms for R-U5-mediated second-strand transfer and its possible role in retrovirus replication and evolution are discussed. PMID:9499117

Programmable molecular recognition based on the geometry of DNA nanostructures.

PubMed

Woo, Sungwook; Rothemund, Paul W K

2011-07-10

From ligand-receptor binding to DNA hybridization, molecular recognition plays a central role in biology. Over the past several decades, chemists have successfully reproduced the exquisite specificity of biomolecular interactions. However, engineering multiple specific interactions in synthetic systems remains difficult. DNA retains its position as the best medium with which to create orthogonal, isoenergetic interactions, based on the complementarity of Watson-Crick binding. Here we show that DNA can be used to create diverse bonds using an entirely different principle: the geometric arrangement of blunt-end stacking interactions. We show that both binary codes and shape complementarity can serve as a basis for such stacking bonds, and explore their specificity, thermodynamics and binding rules. Orthogonal stacking bonds were used to connect five distinct DNA origami. This work, which demonstrates how a single attractive interaction can be developed to create diverse bonds, may guide strategies for molecular recognition in systems beyond DNA nanostructures.

The extent of sequence complementarity correlates with the potency of cellular miRNA-mediated restriction of HIV-1

PubMed Central

Houzet, Laurent; Klase, Zachary; Yeung, Man Lung; Wu, Annie; Le, Shu-Yun; Quiñones, Mariam; Jeang, Kuan-Teh

2012-01-01

MicroRNAs (miRNAs) are 22-nt non-coding RNAs involved in the regulation of cellular gene expression and potential cellular defense against viral infection. Using in silico analyses, we predicted target sites for 22 human miRNAs in the HIV genome. Transfection experiments using synthetic miRNAs showed that five of these miRNAs capably decreased HIV replication. Using one of these five miRNAs, human miR-326 as an example, we demonstrated that the degree of complementarity between the predicted viral sequence and cellular miR-326 correlates, in a Dicer-dependent manner, with the potency of miRNA-mediated restriction of viral replication. Antagomirs to miR-326 that knocked down this cell endogenous miRNA increased HIV-1 replication in cells, suggesting that miR-326 is physiologically functional in moderating HIV-1 replication in human cells. PMID:23042677

Nonlocality versus complementarity: a conservative approach to the information problem

NASA Astrophysics Data System (ADS)

Giddings, Steven B.

2011-01-01

A proposal for resolution of the information paradox is that 'nice slice' states, which have been viewed as providing a sharp argument for information loss, do not in fact do so as they do not give a fully accurate description of the quantum state of a black hole. This however leaves an information problem, which is to provide a consistent description of how information escapes when a black hole evaporates. While a rather extreme form of nonlocality has been advocated in the form of complementarity, this paper argues that is not necessary, and more modest nonlocality could solve the information problem. One possible distinguishing characteristic of scenarios is the information retention time. The question of whether such nonlocality implies acausality, and particularly inconsistency, is briefly addressed. The need for such nonlocality, and its apparent tension with our empirical observations of local quantum field theory, may be a critical missing piece in understanding the principles of quantum gravity.

Attempts to locate residues in complementarity-determining regions of antibody combining sites that make contact with antigen.

PubMed

Kabat, E A; Wu, T T; Bilofsky, H

1976-02-01

From collected data on variable region sequences of heavy chains of immunoglobulins, the probability of random associations of any two amino-acid residues in the complementarity-determining segments was computed, and pairs of residues occurring significantly more frequently than expected were selected by computer. Significant associations between Phe 32 and Tyr 33, Phe 32 and Glu 35, and Tyr 33 and Glu 35 were found in six proteins, all of which were mouse myeloma proteins which bound phosphorylcholine (= phosphocholine). From the x-ray structure of McPC603, Tyr 33 and Glu 35 are contacting residues; a seventh phosphorylcholine-binding mouse myeloma protein also contained Phe 32 and Tyr 33 but position 35 had only been determined as Glx and thus this position had not been selected. Met 34 occurred in all seven phosphorylcholine-binding myeoma proteins but was also present at this position in 29 other proteins and thus was not selected; it is seen in the x-ray structure not to be a contacting residue. The role of Phe 32 is not obvious but it could have some conformational influence. A human phosphorylcholine-binding myeloma protien also had Phe, Tyr, and Met at positions 32, 33, and 34, but had Asp instead of Glu at position 35 and showed a lower binding constant. The ability to use sequence data to locate residues in complementarity-determing segments making contact with antigenic determinants and those playing essentially a structural role would contribute substantially to the understanding of antibody specificity.

Phosphorus acquisition by citrate- and phytase-exuding Nicotiana tabacum plant mixtures depends on soil phosphorus availability and root intermingling.

PubMed

Giles, Courtney D; Richardson, Alan E; Cade-Menun, Barbara J; Mezeli, Malika M; Brown, Lawrie K; Menezes-Blackburn, Daniel; Darch, Tegan; Blackwell, Martin Sa; Shand, Charles A; Stutter, Marc I; Wendler, Renate; Cooper, Patricia; Lumsdon, David G; Wearing, Catherine; Zhang, Hao; Haygarth, Philip M; George, Timothy S

2018-03-02

Citrate and phytase root exudates contribute to improved phosphorus (P) acquisition efficiency in Nicotiana tabacum (tobacco) when both exudates are produced in a P deficient soil. To test the importance of root intermingling in the interaction of citrate and phytase exudates, Nicotiana tabacum plant-lines with constitutive expression of heterologous citrate (Cit) or fungal phytase (Phy) exudation traits were grown under two root treatments (roots separated or intermingled) and in two soils with contrasting soil P availability. Complementarity of plant mixtures varying in citrate efflux rate and mobility of the expressed phytase in soil was determined based on plant biomass and P accumulation. Soil P composition was evaluated using solution 31 P NMR spectroscopy. In the soil with limited available P, positive complementarity occurred in Cit+Phy mixtures with roots intermingled. Root separation eliminated positive interactions in mixtures expressing the less mobile phytase (Aspergillus niger PhyA) whereas positive complementarity persisted in mixtures that expressed the more mobile phytase (Peniophora lycii PhyA). Soils from Cit+Phy mixtures contained less inorganic P and more organic P compared to monocultures. Exudate-specific strategies for the acquisition of soil P were most effective in P-limited soil and depended on citrate efflux rate and the relative mobility of the expressed phytase in soil. Plant growth and soil P utilization in plant systems with complementary exudation strategies are expected to be greatest where exudates persist in soil and are expressed synchronously in space and time. This article is protected by copyright. All rights reserved.

Improving protein-protein interaction prediction using evolutionary information from low-quality MSAs.

PubMed

Várnai, Csilla; Burkoff, Nikolas S; Wild, David L

2017-01-01

Evolutionary information stored in multiple sequence alignments (MSAs) has been used to identify the interaction interface of protein complexes, by measuring either co-conservation or co-mutation of amino acid residues across the interface. Recently, maximum entropy related correlated mutation measures (CMMs) such as direct information, decoupling direct from indirect interactions, have been developed to identify residue pairs interacting across the protein complex interface. These studies have focussed on carefully selected protein complexes with large, good-quality MSAs. In this work, we study protein complexes with a more typical MSA consisting of fewer than 400 sequences, using a set of 79 intramolecular protein complexes. Using a maximum entropy based CMM at the residue level, we develop an interface level CMM score to be used in re-ranking docking decoys. We demonstrate that our interface level CMM score compares favourably to the complementarity trace score, an evolutionary information-based score measuring co-conservation, when combined with the number of interface residues, a knowledge-based potential and the variability score of individual amino acid sites. We also demonstrate, that, since co-mutation and co-complementarity in the MSA contain orthogonal information, the best prediction performance using evolutionary information can be achieved by combining the co-mutation information of the CMM with co-conservation information of a complementarity trace score, predicting a near-native structure as the top prediction for 41% of the dataset. The method presented is not restricted to small MSAs, and will likely improve interface prediction also for complexes with large and good-quality MSAs.

Exploring the Roles of Nucleobase Desolvation and Shape Complementarity during the Misreplication of O6-Methylguanine

PubMed Central

Chavarria, Delia; Ramos-Serrano, Andrea; Hirao, Ichiro; Berdis, Anthony J.

2011-01-01

O6-methylguanine is a miscoding DNA lesion arising from the alkylation of guanine. This report uses the bacteriophage T4 DNA polymerase as a model to probe the roles hydrogen-bonding interactions, shape/size, and nucleobase desolvation during the replication of this miscoding lesion. This was accomplished by using transient kinetic techniques to monitor the kinetic parameters for incorporating and extending natural and non-natural nucleotides. In general, the efficiency of nucleotide incorporation does not depend on the hydrogen-bonding potential of the incoming nucleotide. Instead, nucleobase hydrophobicity and shape complementarity appear to be the preeminent factors controlling nucleotide incorporation. In addition, shape complementarity plays a large role in controlling the extension of various mispairs containing O6-methylguanine. This is evident as the rate constants for extension correlate with proper interglycosyl distances and symmetry between the base angles of the formed mispair. Base pairs not conforming to an acceptable geometry within the polymerase’s active site are refractory to elongation and are processed via exonuclease proofreading. The collective data set encompassing nucleotide incorporation, extension, and excision is used to generate a model accounting for the mutagenic potential of O6-methylguanine observed in vivo. In addition, kinetic studies monitoring the incorporation and extension of non-natural nucleotides identified an analog that displays high selectivity for incorporation opposite O6-methylguanine compared to unmodified purines. The unusual selectivity of this analog for replicating damaged DNA provides a novel biochemical tool to study translesion DNA synthesis. PMID:21819995

Root foraging elicits niche complementarity-dependent yield advantage in the ancient ‘three sisters’ (maize/bean/squash) polyculture

PubMed Central

Zhang, Chaochun; Postma, Johannes A.; York, Larry M.; Lynch, Jonathan P.

2014-01-01

Background and Aims Since ancient times in the Americas, maize, bean and squash have been grown together in a polyculture known as the ‘three sisters’. This polyculture and its maize/bean variant have greater yield than component monocultures on a land-equivalent basis. This study shows that below-ground niche complementarity may contribute to this yield advantage. Methods Monocultures and polycultures of maize, bean and squash were grown in two seasons in field plots differing in nitrogen (N) and phosphorus (P) availability. Root growth patterns of individual crops and entire polycultures were determined using a modified DNA-based technique to discriminate roots of different species. Key Results The maize/bean/squash and maize/bean polycultures had greater yield and biomass production on a land-equivalent basis than the monocultures. Increased biomass production was largely caused by a complementarity effect rather than a selection effect. The differences in root crown architecture and vertical root distribution among the components of the ‘three sisters’ suggest that these species have different, possibly complementary, nutrient foraging strategies. Maize foraged relatively shallower, common bean explored the vertical soil profile more equally, while the root placement of squash depended on P availability. The density of lateral root branching was significantly greater for all species in the polycultures than in the monocultures. Conclusions It is concluded that species differences in root foraging strategies increase total soil exploration, with consequent positive effects on the growth and yield of these ancient polycultures. PMID:25274551

Old Wine in New Bottles: Quantum Theory in Historical Perspective.

ERIC Educational Resources Information Center

Bent, Henry A.

1984-01-01

Discusses similarities between chemistry and three central concepts of quantum physics: (1) stationary states; (2) wave functions; and (3) complementarity. Based on these and other similarities, it is indicated that quantum physics is a chemical physics. (JN)

Risk perception of tsunami in the community of Arauco, Chile - a contribution of risk perception to disaster risk management at local level

NASA Astrophysics Data System (ADS)

Kubisch, M. Sc. Susanne; Edilia Jaque Castillo, Dra.; Braun, JProf. Andreas Ch., ,, Dr.

2017-04-01

The research was carried out in the city center of the coastal community of Arauco, Central Chile. The community of Arauco was one of the most affected communities of the tsunami in Chile, the 27th of February 2010. For the data evaluation, the affected inhabitants of the community have been surveyed via standardized questionnaires. Furthermore experts of different fields, amongst others, Disaster Risk Management (DRM), risk education, urban and regional planning, as well as geology have been consulted in form of expert interviews. The results revealed a high risk perception part of the affected community and a weakness of DRM especially at local level, which opens a gap between the evaluation and treatment of risk by experts and risk perception of the affected community. The risk perception of the affected community, here, is predominantly determined by ecological vulnerability, expressed in direct and indirect experience of a tsunami and by institutional vulnerability, expressed among others by a weakness of DRM at local level and a mistrust in responsible institutions for DRM. Due to the institutional vulnerability and the mistrust in responsible institutions we recommend a Community Based Approach (CBA) to strengthen DRM at local level and to take advantage of the high risk perception and knowledge of the affected community. Involving the community in DRM, we assume to close the gap between risk evaluation of experts and risk perception of the inhabitants and to come up with the unique necessities and conditions at local level. Especially in centralized countries, DRM is less effective, because at the one hand, decisions are made distant from the affected communities, so that measures often do not come up with the unique conditions and necessities at local level, and on the other hand measures often do not find acceptance by the affected community. Furthermore centralized DRM is often not effective and quick in response in case of emergency. Another obstacle for an effective DRM, often forms the general mistrust in governmental institutions. In these cases the participation of the affected communities in form of CBAs are assumed to overcome these problems.

COMPLEMENTARITY OF ECOLOGICAL GOAL FUNCTIONS

EPA Science Inventory

This paper summarizes, in the framework of network environ analysis, a set of analyses of energy-matter flow and storage in steady state systems. The network perspective is used to codify and unify ten ecological orientors or external principles: maximum power (Lotka), maximum st...

Methodology of management of dredging operations II. Applications.

PubMed

Junqua, G; Abriak, N E; Gregoire, P; Dubois, V; Mac Farlane, F; Damidot, D

2006-04-01

This paper presents the new methodology of management of dredging operations. Derived partly from existing methodologies (OECD, PNUE, AIPCN), it aims to be more comprehensive, mixing the qualities and the complementarities of previous methodologies. The application of the methodology has been carried out on the site of the Port of Dunkirk (FRANCE). Thus, a characterization of the sediments of this site has allowed a zoning of the Port to be established in to zones of probable homogeneity of sediments. Moreover, sources of pollution have been identified, with an aim of prevention. Ways of waste improvement have also been developed, to answer regional needs, from a point of view of competitive and territorial intelligence. Their development has required a mutualisation of resources between professionals, research centres and local communities, according to principles of industrial ecology. Lastly, a tool of MultiCriteria Decision-Making Aid (M.C.D.M.A.) has been used to determine the most relevant scenario (or alternative, or action) for a dredging operation intended by the Port of Dunkirk. These applications have confirmed the relevance of this methodology for the management of dredging operations.

Effects of inter and intraspecific diversity and genetic divergence of aquatic fungal communities on leaf litter decomposition-a microcosm experiment.

PubMed

Andrade, Ricardo; Pascoal, Cláudia; Cássio, Fernanda

2016-07-01

Freshwater fungi play a key role in plant litter decomposition and have been used to investigate the relationships between biodiversity and ecosystem functioning in streams. Although there is evidence of positive effects of biodiversity on ecosystem processes, particularly on biomass produced, some studies have shown that neutral or negative effects may occur. We manipulated the composition and the number of species and genotypes in aquatic fungal assemblages creating different levels of genetic divergence to assess effects of fungal diversity on biomass produced and leaf decomposition. Generally, diversity effects on fungal biomass produced were positive, suggesting complementarity between species, but in assemblages with more species positive diversity effects were reduced. Genotype diversity and genetic divergence had net positive effects on leaf mass loss, but in assemblages with higher diversity leaf decomposition decreased. Our results highlight the importance of considering multiple biodiversity measures when investigating the relationship between biodiversity and ecosystem functioning. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Impact of Public Health Awareness Campaigns on the Awareness and Quality of Palliative Care

PubMed Central

2017-01-01

Abstract Objective: The right to health includes a right of access to good quality palliative care, but inequalities persist. Raising awareness is a key plank of the public health approach to palliative care, but involves consideration of subjects most of us prefer not to address. This review addresses the question: “do public health awareness campaigns effectively improve the awareness and quality of palliative care”? Background: The evidence shows that public awareness campaigns can improve awareness of palliative care and probably improve quality of care, but there is a lack of evidence about the latter. Methods: Rapid review and synthesis. Results: A comprehensive public awareness campaign about palliative care (including advance care planning and end-of-life decision making) should be based on clear and shared terminology, use well piloted materials, and the full range of mass media to suit different ages, cultures, and religious/spiritual perspectives. Arts and humanities have a role to play in allowing individuals and communities to express experiences of illness, death, and grief and encourage conversation and thoughtful reflection. There is evidence about key factors for success: targeting, networking, and use of specific, measurable, achievable, realistic time-bound objectives; continuous evaluation; and complementarity to national and international policy. Discussion: Campaigns should be located within the framework of public health promotion and the synergy between short national mass media campaigns and longer term local community action initiatives carefully considered. National and local projects to raise awareness should identify and address any barriers at the level of individuals, communities, and systems of care, for example, literacy skills and unequal access to resources. PMID:29283867

SOIL ECOLOGY AS KEY TO SUSTAINABLE CROP PRODUCTION.

PubMed

De Deyn, G B

2015-01-01

Sustainable production of food, feed and fiberwarrants sustainable soil management and crop protection. The tools available to achieve this are both in the realm of the plants and of the soil, with a key role for plant-soil interactions. At the plant level we have vast knowledge of variation within plant species with respect to pests and diseases, based on which we can breed for resistance. However, given that systems evolve this resistance is bound to be temporarily, hence also other strategies are needed. Here I plea for an integrative approach for sustainable production using ecological principles. Ecology, the study of how organisms interact with their environment, teaches us that diversity promotes productivity and yield stability. These effects are thought to be governed through resource use complementarity and reduced build-up of pests and diseases both above- and belowground. In recent years especially the role of soil biotic interactions has revealed new insights in how plant diversity and productivity are related to soil biodiversity and the functions soil biota govern. In our grassland biodiversity studies we found that root feeders can promote plant diversity and succession without reducing plant community productivity, this illustrates the role of diversity to maintain productivity. Also diversity within species offers scope for sustainable production, for example through awareness of differences between plant genotypes in chemical defense compounds that can attract natural enemies of pests aboveground- and belowground thereby providing plant protection. Plant breeding can also benefit from using complementarity between plant species in the selection for new varieties, as our work demonstrated that when growing in species mixtures plant species adapt to each other over time such that their resource acquisition traits become more complementing. Finally, in a recent meta-analysis we show that earthworms can stimulate crop yield with on average 25%, but also that the effect size is conditional on fertilizer management and crop type. Together these examples illustrate the role of soil ecology in plant growth and the potential of its use for sustainable crop productivity through judicious management of plant-soil interactions.

Complementary habitat use by wild bees in agro-natural landscapes.

PubMed

Mandelik, Yael; Winfree, Rachael; Neeson, Thomas; Kremen, Claire

2012-07-01

Human activity causes abrupt changes in resource availability across the landscape. In order to persist in human-altered landscapes organisms need to shift their habitat use accordingly. Little is known about the mechanisms by which whole communities persist in human-altered landscapes, including the role of complementary habitat use. We define complementary habitat use as the use of different habitats at different times by the same group of species during the course of their activity period. We hypothesize that complementary habitat use is a mechanism through which native bee species persist in human-altered landscapes. To test this idea, we studied wild bee communities in agro-natural landscapes and explored their community-level patterns of habitat and resource use over space and time. The study was conducted in six agro-natural landscapes in the eastern United States, each containing three main bee habitat types (natural habitat, agricultural fields, and old fields). Each of the three habitats exhibited a unique seasonal pattern in amount, diversity, and composition of floral resources, and together they created phenological complementarity in foraging resources for bees. Individual bee species as well as the bee community responded to these spatiotemporal patterns in floral availability and exhibited a parallel pattern of complementary habitat use. The majority of wild bee species, including all the main crop visitors, used fallow areas within crops early in the season, shifted to crops in mid-season, and used old-field habitats later in the season. The natural-forest habitat supported very limited number of bees, mostly visitors of non-crop plants. Old fields are thus an important feature in these arable landscapes for maintaining crop pollination services. Our study provides a detailed examination of how shifts in habitat and resource use may enable bees to persist in highly dynamic agro-natural landscapes, and points to the need for a broad cross-habitat perspective in managing these landscapes.

Urban green space and vibrant communities: exploring the linkage in the Portland Vancouver area

Treesearch

Edward A. Stone; JunJie Wu; Ralph Alig

2015-01-01

This report investigates the interactions between household location decisions and community characteristics, including green space. Household location decisions are a primary driver of land-use change, and collective location decisions affect community characteristics. At the same time, community characteristics affect location decisions. Neighborhoods or communities...

Large Scale Underground Detectors in Europe

NASA Astrophysics Data System (ADS)

Katsanevas, S. K.

2006-07-01

The physics potential and the complementarity of the large scale underground European detectors: Water Cherenkov (MEMPHYS), Liquid Argon TPC (GLACIER) and Liquid Scintillator (LENA) is presented with emphasis on the major physics opportunities, namely proton decay, supernova detection and neutrino parameter determination using accelerator beams.

Robert Frost and the Poetry of Physics.

ERIC Educational Resources Information Center

Coletta, W. John; Tamres, David H.

1992-01-01

Examines five poems by Robert Frost that illustrate Frost's interest in science. The poems include allusions to renowned physicists, metaphoric descriptions of some famous physics experiments, explorations of complementarity as enunciated by Bohr, and poetic formulations of Heisenberg's uncertainty principle. (20 references) (MDH)

Quantifying the relative irreplaceability of important bird and biodiversity areas.

PubMed

Di Marco, Moreno; Brooks, Thomas; Cuttelod, Annabelle; Fishpool, Lincoln D C; Rondinini, Carlo; Smith, Robert J; Bennun, Leon; Butchart, Stuart H M; Ferrier, Simon; Foppen, Ruud P B; Joppa, Lucas; Juffe-Bignoli, Diego; Knight, Andrew T; Lamoreux, John F; Langhammer, Penny F; May, Ian; Possingham, Hugh P; Visconti, Piero; Watson, James E M; Woodley, Stephen

2016-04-01

World governments have committed to increase the global protected areas coverage by 2020, but the effectiveness of this commitment for protecting biodiversity depends on where new protected areas are located. Threshold- and complementarity-based approaches have been independently used to identify important sites for biodiversity. We brought together these approaches by performing a complementarity-based analysis of irreplaceability in important bird and biodiversity areas (IBAs), which are sites identified using a threshold-based approach. We determined whether irreplaceability values are higher inside than outside IBAs and whether any observed difference depends on known characteristics of the IBAs. We focused on 3 regions with comprehensive IBA inventories and bird distribution atlases: Australia, southern Africa, and Europe. Irreplaceability values were significantly higher inside than outside IBAs, although differences were much smaller in Europe than elsewhere. Higher irreplaceability values in IBAs were associated with the presence and number of restricted-range species; number of criteria under which the site was identified; and mean geographic range size of the species for which the site was identified (trigger species). In addition, IBAs were characterized by higher irreplaceability values when using proportional species representation targets, rather than fixed targets. There were broadly comparable results when measuring irreplaceability for trigger species and when considering all bird species, which indicates a good surrogacy effect of the former. Recently, the International Union for Conservation of Nature has convened a consultation to consolidate global standards for the identification of key biodiversity areas (KBAs), building from existing approaches such as IBAs. Our results informed this consultation, and in particular a proposed irreplaceability criterion that will allow the new KBA standard to draw on the strengths of both threshold- and complementarity-based approaches. © 2015 Society for Conservation Biology.

Structural and functional analyses reveal the contributions of the C- and N-lobes of Argonaute protein to selectivity of RNA target cleavage.

PubMed

Dayeh, Daniel M; Kruithoff, Bradley C; Nakanishi, Kotaro

2018-04-27

Some gene transcripts have cellular functions as regulatory noncoding RNAs. For example, ∼23-nucleotide (nt)-long siRNAs are loaded into Argonaute proteins. The resultant ribonucleoprotein assembly, the RNA-induced silencing complex (RISC), cleaves RNAs that are extensively base-paired with the loaded siRNA. To date, base complementarity is recognized as the major determinant of specific target cleavage (or slicing), but little is known about how Argonaute inspects base pairing before cleavage. A hallmark of Argonaute proteins is their bilobal structure, but despite the significance of this structure for curtailing slicing activity against mismatched targets, the molecular mechanism remains elusive. Here, our structural and functional studies of a bilobed yeast Argonaute protein and its isolated catalytic C-terminal lobe (C-lobe) revealed that the C-lobe alone retains almost all properties of bilobed Argonaute: siRNA-duplex loading, passenger cleavage/ejection, and siRNA-dependent RNA cleavage. A 2.1 Å-resolution crystal structure revealed that the catalytic C-lobe mirrors the bilobed Argonaute in terms of guide-RNA recognition and that all requirements for transitioning to the catalytically active conformation reside in the C-lobe. Nevertheless, we found that in the absence of the N-terminal lobe (N-lobe), target RNAs are scanned for complementarity only at positions 5-14 on a 23-nt guide RNA before endonucleolytic cleavage, thereby allowing for some off-target cleavage. Of note, acquisition of an N-lobe expanded the range of the guide RNA strand used for inspecting target complementarity to positions 2-23. These findings offer clues to the evolution of the bilobal structure of catalytically active Argonaute proteins. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Saptio-temporal complementarity of wind and solar power in India

NASA Astrophysics Data System (ADS)

Lolla, Savita; Baidya Roy, Somnath; Chowdhury, Sourangshu

2015-04-01

Wind and solar power are likely to be a part of the solution to the climate change problem. That is why they feature prominently in the energy policies of all industrial economies including India. One of the major hindrances that is preventing an explosive growth of wind and solar energy is the issue of intermittency. This is a major problem because in a rapidly moving economy, energy production must match the patterns of energy demand. Moreover, sudden increase and decrease in energy supply may destabilize the power grids leading to disruptions in power supply. In this work we explore if the patterns of variability in wind and solar energy availability can offset each other so that a constant supply can be guaranteed. As a first step, this work focuses on seasonal-scale variability for each of the 5 regional power transmission grids in India. Communication within each grid is better than communication between grids. Hence, it is assumed that the grids can switch sources relatively easily. Wind and solar resources are estimated using the MERRA Reanalysis data for the 1979-2013 period. Solar resources are calculated with a 20% conversion efficiency. Wind resources are estimated using a 2 MW turbine power curve. Total resources are obtained by optimizing location and number of wind/solar energy farms. Preliminary results show that the southern and western grids are more appropriate for cogeneration than the other grids. Many studies on wind-solar cogeneration have focused on temporal complementarity at local scale. However, this is one of the first studies to explore spatial complementarity over regional scales. This project may help accelerate renewable energy penetration in India by identifying regional grid(s) where the renewable energy intermittency problem can be minimized.

Highly viscous antibody solutions are a consequence of network formation caused by domain-domain electrostatic complementarities: insights from coarse-grained simulations.

PubMed

Buck, Patrick M; Chaudhri, Anuj; Kumar, Sandeep; Singh, Satish K

2015-01-05

Therapeutic monoclonal antibody (mAb) candidates that form highly viscous solutions at concentrations above 100 mg/mL can lead to challenges in bioprocessing, formulation development, and subcutaneous drug delivery. Earlier studies of mAbs with concentration-dependent high viscosity have indicated that mAbs with negatively charged Fv regions have a dipole-like quality that increases the likelihood of reversible self-association. This suggests that weak electrostatic intermolecular interactions can form transient antibody networks that participate in resistance to solution deformation under shear stress. Here this hypothesis is explored by parametrizing a coarse-grained (CG) model of an antibody using the domain charges from four different mAbs that have had their concentration-dependent viscosity behaviors previously determined. Multicopy molecular dynamics simulations were performed for these four CG mAbs at several concentrations to understand the effect of surface charge on mass diffusivity, pairwise interactions, and electrostatic network formation. Diffusion coefficients computed from simulations were in qualitative agreement with experimentally determined viscosities for all four mAbs. Contact analysis revealed an overall greater number of pairwise interactions for the two mAbs in this study with high concentration viscosity issues. Further, using equilibrated solution trajectories, the two mAbs with high concentration viscosity issues quantitatively formed more features of an electrostatic network than the other mAbs. The change in the number of these network features as a function of concentration is related to the number of pairwise interactions formed by electrostatic complementarities between antibody domains. Thus, transient antibody network formation caused by domain-domain electrostatic complementarities is the most probable origin of high concentration viscosity for mAbs in this study.

Crystal structure of an antibody bound to an immunodominant peptide epitope: novel features in peptide-antibody recognition.

PubMed

Nair, D T; Singh, K; Sahu, N; Rao, K V; Salunke, D M

2000-12-15

The crystal structure of Fab of an Ab PC283 complexed with its corresponding peptide Ag, PS1 (HQLDPAFGANSTNPD), derived from the hepatitis B virus surface Ag was determined. The PS1 stretch Gln2P to Phe7P is present in the Ag binding site of the Ab, while the next three residues of the peptide are raised above the binding groove. The residues Ser11P, Thr12P, and Asn13P then loop back onto the Ag-binding site of the Ab. The last two residues, Pro14P and Asp15P, extend outside the binding site without forming any contacts with the Ab. The PC283-PS1 complex is among the few examples where the light chain complementarity-determining regions show more interactions than the heavy chain complementarity-determining regions, and a distal framework residue is involved in Ag binding. As seen from the crystal structure, most of the contacts between peptide and Ab are through the five residues, Leu3-Asp4-Pro5-Ala6-Phe7, of PS1. The paratope is predominantly hydrophobic with aromatic residues lining the binding pocket, although a salt bridge also contributes to stabilizing the Ag-Ab interaction. The molecular surface area buried upon PS1 binding is 756 A(2) for the peptide and 625 A(2) for the Fab, which is higher than what has been seen to date for Ab-peptide complexes. A comparison between PC283 structure and a homology model of its germline ancestor suggests that paratope optimization for PS1 occurs by improving both charge and shape complementarity.

Mate choice for major histocompatibility complex complementarity in a strictly monogamous bird, the grey partridge (Perdix perdix).

PubMed

Rymešová, Dana; Králová, Tereza; Promerová, Marta; Bryja, Josef; Tomášek, Oldřich; Svobodová, Jana; Šmilauer, Petr; Šálek, Miroslav; Albrecht, Tomáš

2017-01-01

Sexual selection has been hypothesised as favouring mate choice resulting in production of viable offspring with genotypes providing high pathogen resistance. Specific pathogen recognition is mediated by genes of the major histocompatibility complex (MHC) encoding proteins fundamental for adaptive immune response in jawed vertebrates. MHC genes may also play a role in odour-based individual recognition and mate choice, aimed at avoiding inbreeding. MHC genes are known to be involved in mate choice in a number of species, with 'good genes' (absolute criteria) and 'complementary genes' (self-referential criteria) being used to explain MHC-based mating. Here, we focus on the effect of morphological traits and variation and genetic similarity between individuals in MHC class IIB (MHCIIB) exon 2 on mating in a free-living population of a monogamous bird, the grey partridge. We found no evidence for absolute mate choice criteria as regards grey partridge MHCIIB genotypes, i.e., number and occurrence of amino acid variants, though red chroma of the spot behind eyes was positively associated with male pairing success. On the other hand, mate choice at MHCIIB was based on relative criteria as females preferentially paired with more dissimilar males having a lower number of shared amino acid variants. This observation supports the 'inbreeding avoidance' and 'complementary genes' hypotheses. Our study provides one of the first pieces of evidence for MHC-based mate choice for genetic complementarity in a strictly monogamous bird. The statistical approach employed can be recommended for testing mating preferences in cases where availability of potential mates (recorded with an appropriate method such as radio-tracking) shows considerable temporal variation. Additional genetic analyses using neutral markers may detect whether MHC-based mate choice for complementarity emerges as a by-product of general inbreeding avoidance in grey partridges.

Male engagement as a strategy to improve utilization and community-based delivery of maternal, newborn and child health services: evidence from an intervention in Odisha, India

PubMed Central

2015-01-01

Background In response to persistently poor levels of maternal, newborn and child health (MNCH) in rural India, the National Rural Health Mission (NRHM) was launched to support the provision of accessible, affordable and quality health care in deprived and underserved communities. The Accredited Social Health Activists (ASHAs), local women, are trained as health promoters to generate demand for, and facilitate access to MNCH care in their communities. While they are also expected to provide husbands of expectant women with information on MNCH care and family planning, their reach to the husbands is limited. The aim of this study is to describe the influence of a male engagement project on the utilization and community-based delivery of MNCH care in a rural district of the country. Methods We used qualitative data from the evaluation of a project which recruited and trained male Community Health Workers (CHWs) known as Male Health Activists (MHAs) to complement the work of ASHAs and target outreach to men. This paper uses data from in-depth interviews (IDIs) with ASHAs (n=11), Anganwadi Workers (AWWs) (n=4) and Auxiliary Nurse Midwives (ANMs) (n=2); with women who had delivered at home, community health center or district hospital in the few months preceding the date of the interview (n=11); and with husbands of these women (n=7). Results Participants’ responses are broadly organized around the facilitation of ASHAs’ work by MHAs, and male engagement activities undertaken by MHAs. More specifically, the narratives reflected gender-based divisions of work and space in three core areas of delivery and use of MNCH services: escorting women to health centers for facility-based deliveries; mobilizing women and children to attend Village Health and Nutrition Days and Immunization Days; and raising awareness among men on MNCH and family planning. Conclusion This study sheds light on male engagement as a strategy to improve the delivery, access and uptake of maternal, newborn and child health in the context of prevailing gender norms and gendered roles in rural India. Ultimately, it unveils the complementarity of male and female CHWs in the community-based delivery of, and increased demand for, MNCH services. PMID:26062910

The diversity of H3 loops determines the antigen-binding tendencies of antibody CDR loops.

PubMed

Tsuchiya, Yuko; Mizuguchi, Kenji

2016-04-01

Of the complementarity-determining regions (CDRs) of antibodies, H3 loops, with varying amino acid sequences and loop lengths, adopt particularly diverse loop conformations. The diversity of H3 conformations produces an array of antigen recognition patterns involving all the CDRs, in which the residue positions actually in contact with the antigen vary considerably. Therefore, for a deeper understanding of antigen recognition, it is necessary to relate the sequence and structural properties of each residue position in each CDR loop to its ability to bind antigens. In this study, we proposed a new method for characterizing the structural features of the CDR loops and obtained the antigen-binding ability of each residue position in each CDR loop. This analysis led to a simple set of rules for identifying probable antigen-binding residues. We also found that the diversity of H3 loop lengths and conformations affects the antigen-binding tendencies of all the CDR loops. © 2016 The Protein Society.

Phosphorylation of an intrinsically disordered segment in Ets1 shifts conformational sampling toward binding-competent substates.

PubMed

Bui, Jennifer M; Gsponer, Jörg

2014-08-05

Functions of many proteins are affected by posttranslational modifications of intrinsically disordered (ID) regions, yet little is known about the underlying molecular mechanisms. By combining molecular dynamics simulations and protein docking, we demonstrate that the addition of phosphates to an ID segment adjacent to the PNT domain of Ets1 directs conformational sampling toward substates that are most compatible with high-affinity binding of the TAZ1 domain of its coactivator CBP. The phosphate charges disrupt salt bridges and thereby open a hydrophobic cleft and expose hydrophobic residues at the ID N terminus. The structure of the PNT-TAZ1 complex that we determined shows that PNT binds to TAZ1 via these hydrophobic regions in a similar manner to how it interacts with other partners. Our calculations reveal a dual effect of phosphorylation in that it changes the dynamics of PNT so that it becomes more compatible for TAZ1 binding and increases complementarity with this binding partner. Copyright © 2014 Elsevier Ltd. All rights reserved.

Regulation of the expression of the cell-cycle gene ftsZ by DicF antisense RNA. Division does not require a fixed number of FtsZ molecules.

PubMed

Tétart, F; Bouché, J P

1992-03-01

We show that the 53-nucleotide RNA molecule encoded by gene dicF blocks cell division in Escherichia coli by inhibiting the translation of ftsZ mRNA. Such a role for dicF had been predicted on the basis of the complementarity of DicF RNA with the ribosome-binding region of the ftsZ mRNA. An analysis of ftsZ expression at its chromosomal locus, and of an ftsZ-lacZ translational fusion controlled by promoters ftsZ1p and ftsZ2p only, indicates that ftsZ is not autoregulated. Partial inhibition of FtsZ synthesis leads to increased cell size. However, the number of FtsZ molecules per cell can be reduced threefold without affecting the division rate significantly. Our results suggest that septation is not triggered by a fixed number of newly synthesized FtsZ molecules per cell.

Automatic forest-fire measuring using ground stations and Unmanned Aerial Systems.

PubMed

Martínez-de Dios, José Ramiro; Merino, Luis; Caballero, Fernando; Ollero, Anibal

2011-01-01

This paper presents a novel system for automatic forest-fire measurement using cameras distributed at ground stations and mounted on Unmanned Aerial Systems (UAS). It can obtain geometrical measurements of forest fires in real-time such as the location and shape of the fire front, flame height and rate of spread, among others. Measurement of forest fires is a challenging problem that is affected by numerous potential sources of error. The proposed system addresses them by exploiting the complementarities between infrared and visual cameras located at different ground locations together with others onboard Unmanned Aerial Systems (UAS). The system applies image processing and geo-location techniques to obtain forest-fire measurements individually from each camera and then integrates the results from all the cameras using statistical data fusion techniques. The proposed system has been extensively tested and validated in close-to-operational conditions in field fire experiments with controlled safety conditions carried out in Portugal and Spain from 2001 to 2006.

Automatic Forest-Fire Measuring Using Ground Stations and Unmanned Aerial Systems

PubMed Central

Martínez-de Dios, José Ramiro; Merino, Luis; Caballero, Fernando; Ollero, Anibal

2011-01-01

This paper presents a novel system for automatic forest-fire measurement using cameras distributed at ground stations and mounted on Unmanned Aerial Systems (UAS). It can obtain geometrical measurements of forest fires in real-time such as the location and shape of the fire front, flame height and rate of spread, among others. Measurement of forest fires is a challenging problem that is affected by numerous potential sources of error. The proposed system addresses them by exploiting the complementarities between infrared and visual cameras located at different ground locations together with others onboard Unmanned Aerial Systems (UAS). The system applies image processing and geo-location techniques to obtain forest-fire measurements individually from each camera and then integrates the results from all the cameras using statistical data fusion techniques. The proposed system has been extensively tested and validated in close-to-operational conditions in field fire experiments with controlled safety conditions carried out in Portugal and Spain from 2001 to 2006. PMID:22163958

The moderating role of absorptive capacity and the differential effects of acquisitions and alliances on Big Pharma firms' innovation performance.

PubMed

Fernald, K D S; Pennings, H P G; van den Bosch, J F; Commandeur, H R; Claassen, E

2017-01-01

In the context of increased pharmaceutical innovation deficits and Big Pharma blockbusters' patent expirations, this paper examines the moderating role of firms' absorptive capacity in external innovation activities of Big Pharma firms. The study indicates a rising interest of Big Pharma in acquisitions of and alliances with biotechnology companies. Unfortunately, this increased interest is not reflected in the number of new drugs generated by Big Pharma. We find that acquisitions of biotech companies have negatively affected Big Pharma firms' innovation performance on average but these acquisitions might have a positive effect at higher levels of acquiring firms' absorptive capacity. Moreover, also acquisitions of pharma companies and alliances with biotech companies only have a positive effect on innovation performance at sufficiently high levels of absorptive capacity. The moderating role of absorptive capacity implicates that a tight integration of internal R&D efforts and (unrelated) external knowledge is crucial for harnessing complementarity effects.

The moderating role of absorptive capacity and the differential effects of acquisitions and alliances on Big Pharma firms' innovation performance

PubMed Central

Fernald, K. D. S.; Pennings, H. P. G.; van den Bosch, J. F.; Commandeur, H. R.; Claassen, E.

2017-01-01

In the context of increased pharmaceutical innovation deficits and Big Pharma blockbusters’ patent expirations, this paper examines the moderating role of firms’ absorptive capacity in external innovation activities of Big Pharma firms. The study indicates a rising interest of Big Pharma in acquisitions of and alliances with biotechnology companies. Unfortunately, this increased interest is not reflected in the number of new drugs generated by Big Pharma. We find that acquisitions of biotech companies have negatively affected Big Pharma firms’ innovation performance on average but these acquisitions might have a positive effect at higher levels of acquiring firms’ absorptive capacity. Moreover, also acquisitions of pharma companies and alliances with biotech companies only have a positive effect on innovation performance at sufficiently high levels of absorptive capacity. The moderating role of absorptive capacity implicates that a tight integration of internal R&D efforts and (unrelated) external knowledge is crucial for harnessing complementarity effects. PMID:28231332

The complexity and ambivalence of immigration attitudes: ambivalent stereotypes predict conflicting attitudes toward immigration policies.

PubMed

Reyna, Christine; Dobria, Ovidiu; Wetherell, Geoffrey

2013-07-01

Americans' conflicted attitudes toward immigrants and immigration has stymied immigration reform for decades. In this article, we explore the nuanced nature of stereotypes about immigrants and how they relate to ambivalent attitudes toward immigrant groups and the disparate array of immigration policies that affect them. Using item response theory and multiple regression analysis, we identified and related stereotypes of different immigrant groups to group-based and policy attitudes. Results demonstrate that ambivalent stereotypes mapped onto ambivalent group-based and immigration policy attitudes. Specifically, stereotypes that portray groups in positive or sympathetic ways predicted positive attitudes toward the group and more supportive attitudes toward policies that facilitate their immigration to the United States. Conversely, negative qualities predicted negative attitudes toward the same group and support for policies that prevent the group from immigrating. Results are discussed in light of current theory related to stereotype content, complementarity of stereotypes, and broader implications for immigration attitudes and policy. PsycINFO Database Record (c) 2013 APA, all rights reserved.

[Power, interdependence and complementarity in hospital work: an analysis from the nursing point of view].

PubMed

Lopes, M J

1997-01-01

This essay intends to discuss recent transformation both to hospital work and nursing work specifically. Analysis privilege inter and intra relations with multidisciplinary teams which is constituted of practices on the therapeutic process present in hospital space-time.

Analysis of Relational Communication in Dyads: New Measurement Procedures.

ERIC Educational Resources Information Center

Rogers, L. Edna; Farace, Richard

Relational communication refers to the control or dominance aspects of message exchange in dyads--distinguishing it from the report or referential aspects of communication. In relational communicational analysis, messages as transactions are emphasized; major theoretical concepts which emerge are symmetry, transitoriness, and complementarity of…

Educating for Safety.

ERIC Educational Resources Information Center

Rothe, J. Peter

1991-01-01

To enhance the chance for success in educating young drivers, there should be a balance between the content, structure, and goals of traffic safety programs and the normative rules governing young people's lives. Presents recommendations for safety education based on the notion of complementarity and using a multiperspective approach. (AF)

Cognitive-Developmental and Behavior-Analytic Theories: Evolving into Complementarity

ERIC Educational Resources Information Center

Overton, Willis F.; Ennis, Michelle D.

2006-01-01

Historically, cognitive-developmental and behavior-analytic approaches to the study of human behavior change and development have been presented as incompatible alternative theoretical and methodological perspectives. This presumed incompatibility has been understood as arising from divergent sets of metatheoretical assumptions that take the form…

The Space Infrared Interferometric Telescope (SPIRIT) and its Complementarity to ALMA

NASA Technical Reports Server (NTRS)

Leisawitz, Dave

2007-01-01

We report results of a pre-Formulation Phase study of SPIRIT, a candidate NASA Origins Probe mission. SPIRIT is a spatial and spectral interferometer with an operating wavelength range 25 - 400 microns. SPIRIT will provide sub-arcsecond resolution images and spectra with resolution R = 3000 in a 1 arcmin field of view to accomplish three primary scientific objectives: (1) Learn how planetary systems form from protostellar disks, and how they acquire their chemical organization; (2) Characterize the family of extrasolar planetary systems by imaging the structure in debris disks to understand how and where planets of different types form; and (3) Learn how high-redshift galaxies formed and merged to form the present-day population of galaxies. In each of these science domains, SPIRIT will yield information complementary to that obtainable with the James Webb Space Telescope (JWST)and the Atacama Large Millimeter Array (ALMA), and all three observatories could operate contemporaneously. Here we shall emphasize the SPIRIT science goals (1) and (2) and the mission's complementarity with ALMA.

Solution of monotone complementarity and general convex programming problems using a modified potential reduction interior point method

DOE PAGES

Huang, Kuo -Ling; Mehrotra, Sanjay

2016-11-08

We present a homogeneous algorithm equipped with a modified potential function for the monotone complementarity problem. We show that this potential function is reduced by at least a constant amount if a scaled Lipschitz condition (SLC) is satisfied. A practical algorithm based on this potential function is implemented in a software package named iOptimize. The implementation in iOptimize maintains global linear and polynomial time convergence properties, while achieving practical performance. It either successfully solves the problem, or concludes that the SLC is not satisfied. When compared with the mature software package MOSEK (barrier solver version 6.0.0.106), iOptimize solves convex quadraticmore » programming problems, convex quadratically constrained quadratic programming problems, and general convex programming problems in fewer iterations. Moreover, several problems for which MOSEK fails are solved to optimality. In addition, we also find that iOptimize detects infeasibility more reliably than the general nonlinear solvers Ipopt (version 3.9.2) and Knitro (version 8.0).« less

Evaluating multiple determinants of the structure of plant-animal mutualistic networks.

PubMed

Vázquez, Diego P; Chacoff, Natacha P; Cagnolo, Luciano

2009-08-01

The structure of mutualistic networks is likely to result from the simultaneous influence of neutrality and the constraints imposed by complementarity in species phenotypes, phenologies, spatial distributions, phylogenetic relationships, and sampling artifacts. We develop a conceptual and methodological framework to evaluate the relative contributions of these potential determinants. Applying this approach to the analysis of a plant-pollinator network, we show that information on relative abundance and phenology suffices to predict several aggregate network properties (connectance, nestedness, interaction evenness, and interaction asymmetry). However, such information falls short of predicting the detailed network structure (the frequency of pairwise interactions), leaving a large amount of variation unexplained. Taken together, our results suggest that both relative species abundance and complementarity in spatiotemporal distribution contribute substantially to generate observed network patters, but that this information is by no means sufficient to predict the occurrence and frequency of pairwise interactions. Future studies could use our methodological framework to evaluate the generality of our findings in a representative sample of study systems with contrasting ecological conditions.

Multidimensional entropic uncertainty relation based on a commutator matrix in position and momentum spaces

NASA Astrophysics Data System (ADS)

Hertz, Anaelle; Vanbever, Luc; Cerf, Nicolas J.

2018-01-01

The uncertainty relation for continuous variables due to Byałinicki-Birula and Mycielski [I. Białynicki-Birula and J. Mycielski, Commun. Math. Phys. 44, 129 (1975), 10.1007/BF01608825] expresses the complementarity between two n -tuples of canonically conjugate variables (x1,x2,...,xn) and (p1,p2,...,pn) in terms of Shannon differential entropy. Here we consider the generalization to variables that are not canonically conjugate and derive an entropic uncertainty relation expressing the balance between any two n -variable Gaussian projective measurements. The bound on entropies is expressed in terms of the determinant of a matrix of commutators between the measured variables. This uncertainty relation also captures the complementarity between any two incompatible linear canonical transforms, the bound being written in terms of the corresponding symplectic matrices in phase space. Finally, we extend this uncertainty relation to Rényi entropies and also prove a covariance-based uncertainty relation which generalizes the Robertson relation.

Identification of a sequence element on the 3' side of AAUAAA which is necessary for simian virus 40 late mRNA 3'-end processing.

PubMed Central

Sadofsky, M; Connelly, S; Manley, J L; Alwine, J C

1985-01-01

Our previous studies of the 3'-end processing of simian virus 40 late mRNAs indicated the existence of an essential element (or elements) downstream of the AAUAAA signal. We report here the use of transient expression analysis to study a functional element which we located within the sequence AGGUUUUUU, beginning 59 nucleotides downstream of the recognized signal AAUAAA. Deletion of this element resulted in (i) at least a 75% drop in 3'-end processing at the normal site and (ii) appearance of readthrough transcripts with alternate 3' ends. Some flexibility in the downstream position of this element relative to the AAUAAA was noted by deletion analysis. Using computer sequence comparison, we located homologous regions within downstream sequences of other genes, suggesting a generalized sequence element. In addition, specific complementarity is noted between the downstream element and U4 RNA. The possibility that this complementarity could participate in 3'-end site selection is discussed. Images PMID:3016512

Humanization of Antibodies Using Heavy Chain Complementarity-determining Region 3 Grafting Coupled with in Vitro Somatic Hypermutation*

PubMed Central

Bowers, Peter M.; Neben, Tamlyn Y.; Tomlinson, Geoffery L.; Dalton, Jennifer L.; Altobell, Larry; Zhang, Xue; Macomber, John L.; Wu, Betty F.; Toobian, Rachelle M.; McConnell, Audrey D.; Verdino, Petra; Chau, Betty; Horlick, Robert A.; King, David J.

2013-01-01

A method for simultaneous humanization and affinity maturation of monoclonal antibodies has been developed using heavy chain complementarity-determining region (CDR) 3 grafting combined with somatic hypermutation in vitro. To minimize the amount of murine antibody-derived antibody sequence used during humanization, only the CDR3 region from a murine antibody that recognizes the cytokine hβNGF was grafted into a nonhomologous human germ line V region. The resulting CDR3-grafted HC was paired with a CDR-grafted light chain, displayed on the surface of HEK293 cells, and matured using in vitro somatic hypermutation. A high affinity humanized antibody was derived that was considerably more potent than the parental antibody, possessed a low pm dissociation constant, and demonstrated potent inhibition of hβNGF activity in vitro. The resulting antibody contained half the heavy chain murine donor sequence compared with the same antibody humanized using traditional methods. PMID:23355464

Quantum subsystems: Exploring the complementarity of quantum privacy and error correction

NASA Astrophysics Data System (ADS)

Jochym-O'Connor, Tomas; Kribs, David W.; Laflamme, Raymond; Plosker, Sarah

2014-09-01

This paper addresses and expands on the contents of the recent Letter [Phys. Rev. Lett. 111, 030502 (2013), 10.1103/PhysRevLett.111.030502] discussing private quantum subsystems. Here we prove several previously presented results, including a condition for a given random unitary channel to not have a private subspace (although this does not mean that private communication cannot occur, as was previously demonstrated via private subsystems) and algebraic conditions that characterize when a general quantum subsystem or subspace code is private for a quantum channel. These conditions can be regarded as the private analog of the Knill-Laflamme conditions for quantum error correction, and we explore how the conditions simplify in some special cases. The bridge between quantum cryptography and quantum error correction provided by complementary quantum channels motivates the study of a new, more general definition of quantum error-correcting code, and we initiate this study here. We also consider the concept of complementarity for the general notion of a private quantum subsystem.

Steering operational synergies in terrestrial observation networks: opportunity for advancing Earth system dynamics modelling

NASA Astrophysics Data System (ADS)

Baatz, Roland; Sullivan, Pamela L.; Li, Li; Weintraub, Samantha R.; Loescher, Henry W.; Mirtl, Michael; Groffman, Peter M.; Wall, Diana H.; Young, Michael; White, Tim; Wen, Hang; Zacharias, Steffen; Kühn, Ingolf; Tang, Jianwu; Gaillardet, Jérôme; Braud, Isabelle; Flores, Alejandro N.; Kumar, Praveen; Lin, Henry; Ghezzehei, Teamrat; Jones, Julia; Gholz, Henry L.; Vereecken, Harry; Van Looy, Kris

2018-05-01

Advancing our understanding of Earth system dynamics (ESD) depends on the development of models and other analytical tools that apply physical, biological, and chemical data. This ambition to increase understanding and develop models of ESD based on site observations was the stimulus for creating the networks of Long-Term Ecological Research (LTER), Critical Zone Observatories (CZOs), and others. We organized a survey, the results of which identified pressing gaps in data availability from these networks, in particular for the future development and evaluation of models that represent ESD processes, and provide insights for improvement in both data collection and model integration. From this survey overview of data applications in the context of LTER and CZO research, we identified three challenges: (1) widen application of terrestrial observation network data in Earth system modelling, (2) develop integrated Earth system models that incorporate process representation and data of multiple disciplines, and (3) identify complementarity in measured variables and spatial extent, and promoting synergies in the existing observational networks. These challenges lead to perspectives and recommendations for an improved dialogue between the observation networks and the ESD modelling community, including co-location of sites in the existing networks and further formalizing these recommendations among these communities. Developing these synergies will enable cross-site and cross-network comparison and synthesis studies, which will help produce insights around organizing principles, classifications, and general rules of coupling processes with environmental conditions.

Predatory birds and ants partition caterpillar prey by body size and diet breadth.

PubMed

Singer, Michael S; Clark, Robert E; Lichter-Marck, Issac H; Johnson, Emily R; Mooney, Kailen A

2017-10-01

The effects of predator assemblages on herbivores are predicted to depend critically on predator-predator interactions and the extent to which predators partition prey resources. The role of prey heterogeneity in generating such multiple predator effects has received limited attention. Vertebrate and arthropod insectivores constitute two co-dominant predatory taxa in many ecosystems, and the emergent properties of their joint effects on insect herbivores inform theory on multiple predator effects as well as biological control of insect herbivores. Here we use a large-scale factorial manipulation to assess the extent to which birds and ants engage in antagonistic predator-predator interactions and the consequences of heterogeneity in herbivore body size and diet breadth (i.e. the diversity of host plants used) for prey partitioning. We excluded birds and reduced ant density (by 60%) in the canopies of eight northeastern USA deciduous tree species during two consecutive years and measured the community composition and traits of lepidopteran larvae (caterpillars). Birds did not affect ant density, implying limited intraguild predation between these taxa in this system. Birds preyed selectively upon large-bodied caterpillars (reducing mean caterpillar length by 12%) and ants preyed selectively upon small-bodied caterpillars (increasing mean caterpillar length by 6%). Birds and ants also partitioned caterpillar prey by diet breadth. Birds reduced the frequency dietary generalist caterpillars by 24%, while ants had no effect. In contrast, ants reduced the frequency of dietary specialists by 20%, while birds had no effect, but these effects were non-additive; under bird exclusion, ants had no detectable effect, while in the presence of birds, they reduced the frequency of specialists by 40%. As a likely result of prey partitioning by body size and diet breadth, the combined effects of birds and ants on total caterpillar density were additive, with birds and ants reducing caterpillar density by 44% and 20% respectively. These results show evidence for the role of prey heterogeneity in driving functional complementarity among predators and enhanced top-down control. Heterogeneity in herbivore body size and diet breadth, as well as other prey traits, may represent key predictors of the strength of top-down control from predator communities. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Daily variation in net primary production and net calcification in coral reef communities exposed to elevated pCO2

NASA Astrophysics Data System (ADS)

Comeau, Steeve; Edmunds, Peter J.; Lantz, Coulson A.; Carpenter, Robert C.

2017-07-01

The threat represented by ocean acidification (OA) for coral reefs has received considerable attention because of the sensitivity of calcifiers to changing seawater carbonate chemistry. However, most studies have focused on the organismic response of calcification to OA, and only a few have addressed community-level effects, or investigated parameters other than calcification, such as photosynthesis. Light (photosynthetically active radiation, PAR) is a driver of biological processes on coral reefs, and the possibility that these processes might be perturbed by OA has important implications for community function. Here we investigate how CO2 enrichment affects the relationships between PAR and community net O2 production (Pnet), and between PAR and community net calcification (Gnet), using experiments on three coral communities constructed to match (i) the back reef of Mo'orea, French Polynesia, (ii) the fore reef of Mo'orea, and (iii) the back reef of O'ahu, Hawaii. The results were used to test the hypothesis that OA affects the relationship between Pnet and Gnet. For the three communities tested, pCO2 did not affect the Pnet-PAR relationship, but it affected the intercept of the hyperbolic tangent curve fitting the Gnet-PAR relationship for both reef communities in Mo'orea (but not in O'ahu). For the three communities, the slopes of the linear relationships between Pnet and Gnet were not affected by OA, although the intercepts were depressed by the inhibitory effect of high pCO2 on Gnet. Our result indicates that OA can modify the balance between net calcification and net photosynthesis of reef communities by depressing community calcification, but without affecting community photosynthesis.

Constructing Identities in Multicultural Learning Contexts

ERIC Educational Resources Information Center

Crafter, Sarah; de Abreu, Guida

2010-01-01

In this article we examine two concepts that aid our understanding of processes of identification in multiethnic schools. The first concept focuses on the complementarity of "three processes of identity" (identifying the other, being identified, and self-identification). This is brought together with the concept of sociocultural coupling…

Formative Assessment Probes: Pendulums and Crooked Swings--Connecting Science and Engineering

ERIC Educational Resources Information Center

Keeley, Page

2013-01-01

The "Next Generation Science Standards" provide opportunities for students to experience the link between science and engineering. In the December 2011 issue of "Science and Children," Rodger Bybee explains: "The relationship between science and engineering practices is one of complementarity. Given the inclusion of…

Complementarity of statistical treatments to reconstruct worldwide routes of invasion: The case of the Asian ladybird Harmonia axyridis

USDA-ARS?s Scientific Manuscript database

Technical Abstract. Molecular markers can provide clear insight into the introduction history of invasive species. However, inferences about recent introduction histories remain challenging, because of the stochastic demographic processes often involved. Approximate Bayesian computation (ABC) can he...

Momentary Patterns of Covariation between Specific Affects and Interpersonal Behavior: Linking Relationship Science and Personality Assessment

PubMed Central

Ross, Jaclyn M.; Girard, Jeffrey M.; Wright, Aidan G.C.; Beeney, Joseph E.; Scott, Lori N.; Hallquist, Michael N.; Lazarus, Sophie A.; Stepp, Stephanie D.; Pilkonis, Paul A.

2016-01-01

Relationships are among the most salient factors affecting happiness and wellbeing for individuals and families. Relationship science has identified the study of dyadic behavioral patterns between couple members during conflict as an important window in to relational functioning with both short-term and long-term consequences. Several methods have been developed for the momentary assessment of behavior during interpersonal transactions. Among these, the most popular is the Specific Affect Coding System (SPAFF), which organizes social behavior into a set of discrete behavioral constructs. This study examines the interpersonal meaning of the SPAFF codes through the lens of interpersonal theory, which uses the fundamental dimensions of Dominance and Affiliation to organize interpersonal behavior. A sample of 67 couples completed a conflict task, which was video recorded and coded using SPAFF and a method for rating momentary interpersonal behavior, the Continuous Assessment of Interpersonal Dynamics (CAID). Actor partner interdependence models in a multilevel structural equation modeling framework were used to study the covariation of SPAFF codes and CAID ratings. Results showed that a number of SPAFF codes had clear interpersonal signatures, but many did not. Additionally, actor and partner effects for the same codes were strongly consistent with interpersonal theory’s principle of complementarity. Thus, findings reveal points of convergence and divergence in the two systems and provide support for central tenets of interpersonal theory. Future directions based on these initial findings are discussed. PMID:27148786

Momentary patterns of covariation between specific affects and interpersonal behavior: Linking relationship science and personality assessment.

PubMed

Ross, Jaclyn M; Girard, Jeffrey M; Wright, Aidan G C; Beeney, Joseph E; Scott, Lori N; Hallquist, Michael N; Lazarus, Sophie A; Stepp, Stephanie D; Pilkonis, Paul A

2017-02-01

Relationships are among the most salient factors affecting happiness and wellbeing for individuals and families. Relationship science has identified the study of dyadic behavioral patterns between couple members during conflict as an important window in to relational functioning with both short-term and long-term consequences. Several methods have been developed for the momentary assessment of behavior during interpersonal transactions. Among these, the most popular is the Specific Affect Coding System (SPAFF), which organizes social behavior into a set of discrete behavioral constructs. This study examines the interpersonal meaning of the SPAFF codes through the lens of interpersonal theory, which uses the fundamental dimensions of Dominance and Affiliation to organize interpersonal behavior. A sample of 67 couples completed a conflict task, which was video recorded and coded using SPAFF and a method for rating momentary interpersonal behavior, the Continuous Assessment of Interpersonal Dynamics (CAID). Actor partner interdependence models in a multilevel structural equation modeling framework were used to study the covariation of SPAFF codes and CAID ratings. Results showed that a number of SPAFF codes had clear interpersonal signatures, but many did not. Additionally, actor and partner effects for the same codes were strongly consistent with interpersonal theory's principle of complementarity. Thus, findings reveal points of convergence and divergence in the 2 systems and provide support for central tenets of interpersonal theory. Future directions based on these initial findings are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The soil carbon/nitrogen ratio and moisture affect microbial community structures in alkaline permafrost-affected soils with different vegetation types on the Tibetan plateau.

PubMed

Zhang, Xinfang; Xu, Shijian; Li, Changming; Zhao, Lin; Feng, Huyuan; Yue, Guangyang; Ren, Zhengwei; Cheng, Guogdong

2014-01-01

In the Tibetan permafrost region, vegetation types and soil properties have been affected by permafrost degradation, but little is known about the corresponding patterns of their soil microbial communities. Thus, we analyzed the effects of vegetation types and their covariant soil properties on bacterial and fungal community structure and membership and bacterial community-level physiological patterns. Pyrosequencing and Biolog EcoPlates were used to analyze 19 permafrost-affected soil samples from four principal vegetation types: swamp meadow (SM), meadow (M), steppe (S) and desert steppe (DS). Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria dominated bacterial communities and the main fungal phyla were Ascomycota, Basidiomycota and Mucoromycotina. The ratios of Proteobacteria/Acidobacteria decreased in the order: SM>M>S>DS, whereas the Ascomycota/Basidiomycota ratios increased. The distributions of carbon and nitrogen cycling bacterial genera detected were related to soil properties. The bacterial communities in SM/M soils degraded amines/amino acids very rapidly, while polymers were degraded rapidly by S/DS communities. UniFrac analysis of bacterial communities detected differences among vegetation types. The fungal UniFrac community patterns of SM differed from the others. Redundancy analysis showed that the carbon/nitrogen ratio had the main effect on bacteria community structures and their diversity in alkaline soil, whereas soil moisture was mainly responsible for structuring fungal communities. Thus, microbial communities and their functioning are probably affected by soil environmental change in response to permafrost degradation. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Tree Size Inequality Reduces Forest Productivity: An Analysis Combining Inventory Data for Ten European Species and a Light Competition Model.

PubMed

Bourdier, Thomas; Cordonnier, Thomas; Kunstler, Georges; Piedallu, Christian; Lagarrigues, Guillaume; Courbaud, Benoit

2016-01-01

Plant structural diversity is usually considered as beneficial for ecosystem functioning. For instance, numerous studies have reported positive species diversity-productivity relationships in plant communities. However, other aspects of structural diversity such as individual size inequality have been far less investigated. In forests, tree size inequality impacts directly tree growth and asymmetric competition, but consequences on forest productivity are still indeterminate. In addition, the effect of tree size inequality on productivity is likely to vary with species shade-tolerance, a key ecological characteristic controlling asymmetric competition and light resource acquisition. Using plot data from the French National Geographic Agency, we studied the response of stand productivity to size inequality for ten forest species differing in shade tolerance. We fitted a basal area stand production model that included abiotic factors, stand density, stand development stage and a tree size inequality index. Then, using a forest dynamics model we explored whether mechanisms of light interception and light use efficiency could explain the tree size inequality effect observed for three of the ten species studied. Size inequality negatively affected basal area increment for seven out of the ten species investigated. However, this effect was not related to the shade tolerance of these species. According to the model simulations, the negative tree size inequality effect could result both from reduced total stand light interception and reduced light use efficiency. Our results demonstrate that negative relationships between size inequality and productivity may be the rule in tree populations. The lack of effect of shade tolerance indicates compensatory mechanisms between effect on light availability and response to light availability. Such a pattern deserves further investigations for mixed forests where complementarity effects between species are involved. When studying the effect of structural diversity on ecosystem productivity, tree size inequality is a major facet that should be taken into account.

Leaf economics spectrum-productivity relationships in intensively grazed pastures depend on dominant species identity.

PubMed

Mason, Norman W H; Orwin, Kate; Lambie, Suzanne; Woodward, Sharon L; McCready, Tiffany; Mudge, Paul

2016-05-01

Plant functional traits are thought to drive variation in primary productivity. However, there is a lack of work examining how dominant species identity affects trait-productivity relationships. The productivity of 12 pasture mixtures was determined in a 3-year field experiment. The mixtures were based on either the winter-active ryegrass (Lolium perenne) or winter-dormant tall fescue (Festuca arundinacea). Different mixtures were obtained by adding forb, legume, and grass species that differ in key leaf economics spectrum (LES) traits to the basic two-species dominant grass-white clover (Trifolium repens) mixtures. We tested for correlations between community-weighted mean (CWM) trait values, functional diversity, and productivity across all plots and within those based on either ryegrass or tall fescue. The winter-dormant forb species (chicory and plantain) had leaf traits consistent with high relative growth rates both per unit leaf area (high leaf thickness) and per unit leaf dry weight (low leaf dry matter content). Together, the two forb species achieved reasonable abundance when grown with either base grass (means of 36% and 53% of total biomass, respectively, with ryegrass tall fescue), but they competed much more strongly with tall fescue than with ryegrass. Consequently, they had a net negative impact on productivity when grown with tall fescue, and a net positive effect when grown with ryegrass. Strongly significant relationships between productivity and CWM values for LES traits were observed across ryegrass-based mixtures, but not across tall fescue-based mixtures. Functional diversity did not have a significant positive effect on productivity for any of the traits. The results show dominant species identity can strongly modify trait-productivity relationships in intensively grazed pastures. This was due to differences in the intensity of competition between dominant species and additional species, suggesting that resource-use complementarity is a necessary prerequisite for trait-productivity relationships.

Using environmental heterogeneity to plan for sea-level rise.

PubMed

Hunter, Elizabeth A; Nibbelink, Nathan P

2017-12-01

Environmental heterogeneity is increasingly being used to select conservation areas that will provide for future biodiversity under a variety of climate scenarios. This approach, termed conserving nature's stage (CNS), assumes environmental features respond to climate change more slowly than biological communities, but will CNS be effective if the stage were to change as rapidly as the climate? We tested the effectiveness of using CNS to select sites in salt marshes for conservation in coastal Georgia (U.S.A.), where environmental features will change rapidly as sea level rises. We calculated species diversity based on distributions of 7 bird species with a variety of niches in Georgia salt marshes. Environmental heterogeneity was assessed across six landscape gradients (e.g., elevation, salinity, and patch area). We used 2 approaches to select sites with high environmental heterogeneity: site complementarity (environmental diversity [ED]) and local environmental heterogeneity (environmental richness [ER]). Sites selected based on ER predicted present-day species diversity better than randomly selected sites (up to an 8.1% improvement), were resilient to areal loss from SLR (1.0% average areal loss by 2050 compared with 0.9% loss of randomly selected sites), and provided habitat to a threatened species (0.63 average occupancy compared with 0.6 average occupancy of randomly selected sites). Sites selected based on ED predicted species diversity no better or worse than random and were not resilient to SLR (2.9% average areal loss by 2050). Despite the discrepancy between the 2 approaches, CNS is a viable strategy for conservation site selection in salt marshes because the ER approach was successful. It has potential for application in other coastal areas where SLR will affect environmental features, but its performance may depend on the magnitude of geological changes caused by SLR. Our results indicate that conservation planners that had heretofore excluded low-lying coasts from CNS planning could include coastal ecosystems in regional conservation strategies. © 2017 Society for Conservation Biology.

Linking Research and Teaching: Context, Conflict and Complementarity

ERIC Educational Resources Information Center

Pan, Wei; Cotton, Debby; Murray, Paul

2014-01-01

Although research and teaching have often been regarded as complementary in enhancing the quality of student learning, little previous research has explored the conflicts associated with linking the two activities. This paper aims to examine specific issues arising within the environmental building disciplines at a UK university, and to explore…

Criterion-Referenced and Norm-Referenced Assessments: Compatibility and Complementarity

ERIC Educational Resources Information Center

Lok, Beatrice; McNaught, Carmel; Young, Kenneth

2016-01-01

The tension between criterion-referenced and norm-referenced assessment is examined in the context of curriculum planning and assessment in outcomes-based approaches to higher education. This paper argues the importance of a criterion-referenced assessment approach once an outcomes-based approach has been adopted. It further discusses the…

Health and Schooling: Evidence and Policy Implications for Developing Countries.

ERIC Educational Resources Information Center

Gomes-Neto, Joao Batista; And Others

1997-01-01

Exploits a unique data set (EDRURAL) from three northeastern states of Brazil to investigate the complementarities of health with school attainment and cognitive achievement. The promotion models and value-added achievement models demonstrate the value of students' visual acuity. Achievement models highlight the role of good nutrition. Eye…

Compound Complementarities in the Study of Motivated Behavior.

ERIC Educational Resources Information Center

Teitelbaum, Philip; Stricker, Edward M.

1994-01-01

The 1954 article by Eliot Stellar provided the theoretical focus for a great deal of research on the biological bases of human behavior. Future attention to the infrastructure of behaviors being studied, combined with reductionistic studies of neurons, will fulfill the potential contribution to behavioral neuroscience implicit in Stellar's…

Inclusive Education--A Christian Perspective to an "Overlapping Consensus"

ERIC Educational Resources Information Center

Pirner, Manfred L.

2015-01-01

The UN Convention on the Rights of Persons with Disabilities has triggered endeavours in many countries to implement inclusive education at public schools. A Christian interpretation that concentrates on the anthropogical themes of fragmentarity, fragility and complementarity offers valuable impulses to the public discourse on inclusive education,…

Racial Interaction Effects and Student Achievement

ERIC Educational Resources Information Center

Penney, Jeffrey

2017-01-01

Previous research has found that students who are of the same race as their teacher tend to perform better academically. This paper examines the possibility that both dosage and timing matter for these racial complementarities. Using a model of education production that explicitly accounts for past observable inputs, a conditional…

Interpersonal Attraction and Machiavellianism: A Study of Roommate Pairs.

ERIC Educational Resources Information Center

Riedel, Marc; Thew, Karen

The study attempts to test hypotheses derived from the model of interpersonal attraction suggested by Kerckhoff and Davis, who investigated the issue of need complementarity versus similarity in their longitudinal research upon couples who were engaged or otherwise seriously attached and who proposed that homogamy in social attributes is…

Integrating PCR Theory and Bioinformatics into a Research-oriented Primer Design Exercise

ERIC Educational Resources Information Center

Robertson, Amber L.; Phillips, Allison R.

2008-01-01

Polymerase chain reaction (PCR) is a conceptually difficult technique that embodies many fundamental biological processes. Traditionally, students have struggled to analyze PCR results due to an incomplete understanding of the biological concepts (theory) of DNA replication and strand complementarity. Here we describe the design of a novel…

The Person Approach: Concepts, Measurement Models, and Research Strategy

ERIC Educational Resources Information Center

Magnusson, David

2003-01-01

This chapter discusses the "person approach" to studying developmental processes by focusing on the distinction and complementarity between this holistic-interactionistic framework and what has become designated as the variable approach. Particular attention is given to measurement models for use in the person approach. The discussion on the…

Perspektiven der angewandten Linguistik (Perspectives in Applied Linguistics).

ERIC Educational Resources Information Center

Watts, Richard J., Ed.; Werlen, Iwar, Ed.

1995-01-01

Articles in this issue include: "Complementarite et concurrence des politiques linguistiques au Canada: Le choix du medium d'instruction au Quebec et en Ontario" (The Complementarity and Competition of Language Policies in Canada: The Choice of Medium of Instruction in Quebec and Ontario) (Normand Labrie); "Presentation de la…

Radical Behaviorism and Buddhism: Complementarities and Conflicts

ERIC Educational Resources Information Center

Diller, James W.; Lattal, Kennon A.

2008-01-01

Comparisons have been made between Buddhism and the philosophy of science in general, but there have been only a few attempts to draw comparisons directly with the philosophy of radical behaviorism. The present review therefore considers heretofore unconsidered points of comparison between Buddhism and radical behaviorism in terms of their…

A role for communities in primary prevention of chronic illness? Case studies in regional Australia.

PubMed

Taylor, Judy; Braunack-Mayer, Annette; Cargo, Margaret; Larkins, Sarah; Preston, Robyn

2013-08-01

In regional Australia "communities of place," defined as bounded geographic locations with a local society, undertake community-wide primary prevention programs. In helping to prevent chronic illness, communities provide valuable resources to the health system. To understand the role of community-health sector partnerships for primary prevention and the community contextual factors that affect them, we studied eight partnerships. We used an embedded multiple case study design and collected data through interviews, nonparticipant observation, and document analysis. These data were analyzed using a typology of community-health sector partnerships and community interaction theory to frame the key community contextual factors that affected partnerships. The dominant factor affecting all partnerships was the presence of a collective commitment that communities brought to making the community a better place through developing health. We call this a communitarian approach. Additional research to investigate factors influencing a communitarian approach and the role it plays in partnerships is required.

Urban and Community Forestry Achievements in 1998

Treesearch

Daniel Liptzin; Robert Neville

1999-01-01

The vision for urban and community forestry in the Northeastern Area has remained essentially constant since 1990, "...to achieve community sustainability and an enhanced quality of life through stewardship of urban and community forests and related natural resources." Implied in this statement is full participation by all those who affect or are affected by...

Assessing Fiscal Impact of Rural Growth. Coping With Growth.

ERIC Educational Resources Information Center

Siegler, Theodore R.; Meyer, Neil L.

Growth or development affects a rural community in three separate but interrelated areas: private, social, and public sectors. Private impacts are economic shocks to businesses and citizens of the community. Social impacts affect the community structure as well as individuals within the community, i.e., increased property tax costs may create…

COSPAR/PRBEM international working group activities report

NASA Astrophysics Data System (ADS)

Bourdarie, S.; Blake, B.; Cao, J. B.; Friedel, R.; Miyoshi, Y.; Panasyuk, M.; Underwood, C.

It is now clear to everybody that the current standard AE8 AP8 model for ionising particle specification in the radiation belts must be updated But such an objective is quite difficult to reach just as a reminder to develop AE8 AP8 model in the seventies was 10 persons full time for ten years It is clear that world-wide efforts must be combined because not any individual group has the human resource to perform these new models by themselves Under COSPAR umbrella an international group of expert well distributed around the world has been created to set up a common framework for everybody involved in this field Planned activities of the international group of experts are to - Define users needs - Provide guidelines for standard file format for ionising measurements - Set up guidelines to process in-situ data on a common basis - Decide in which form the new models will have to be - Centralise all progress done world-wide to advise the community - Try to organise world-wide activities as a project to ensure complementarities and more efficiencies between all efforts done Activities of this working group since its creation will be reported as well as future plans

Adaptive significance of the Indian caste system: an ecological perspective.

PubMed

Gadgil, M; Malhotra, K C

1983-01-01

Indian society is an agglomeration of several thousand endogamous groups or castes each with a restricted geographical range and a hereditarily determined mode of subsistence. These reproductively isolated castes may be compared to biological species, and the society thought of as a biological community with each caste having its specific ecological niche. In this paper we examine the ecological-niche relationships of castes which are directly dependent on natural resources. Evidence is presented to show that castes living together in the same region had so organized their pattern of resource use as to avoid excessive intercaste competition for limiting resources. Furthermore, territorial division of the total range of the caste regulated intra-caste competition. Hence, a particular plant or animal resource in a given locality was used almost exclusively by a given lineage within a caste generation after generation. This favoured the cultural evolution of traditions ensuring sustainable use of natural resources. This must have contributed significantly to the stability of Indian caste society over several thousand years. The collapse of the base of natural resources and increasing monetarization of the economy has, however, destroyed the earlier complementarity between the different castes and led to increasing conflicts between them in recent years.

Pollen Deposition Is More Important than Species Richness for Seed Set in Luffa Gourd.

PubMed

Ali, M; Saeed, S; Sajjad, A

2016-10-01

In the context of global biodiversity decline, it is imperative to understand the different aspects of bee communities for sustaining the vital ecosystem service of pollination. Bee species can be assigned to functional groups (average difference among species in functionally related traits) on the basis of complementarity (trait variations exhibited by individual organisms) in their behavior but is not yet known which functional group trait is most important for seed set. In this study, first, the functional groups of bees were made based on their five selected traits (pollen deposition, visitation rate, stay time, visiting time of the day, body size) and then related to the seed set of obligate cross-pollinated Luffa gourd (Luffa aegyptiaca). We found that bee diversity and abundance differed significantly among the studied plots, but only the bee species richness was positively related to the seed set. Functional group diversity in terms of pollen deposition explained even more of the variance in seed set (r 2  = 0.74) than did the species richness (r 2  = 0.53) making it the most important trait of bee species for predicting the crop reproductive success.

Phylogenetically diverse macrophyte community promotes species diversity of mobile epi-benthic invertebrates

NASA Astrophysics Data System (ADS)

Nakamoto, Kenta; Hayakawa, Jun; Kawamura, Tomohiko; Kodama, Masafumi; Yamada, Hideaki; Kitagawa, Takashi; Watanabe, Yoshiro

2018-07-01

Various aspects of plant diversity such as species diversity and phylogenetic diversity enhance the species diversity of associated animals in terrestrial systems. In marine systems, however, the effects of macrophyte diversity on the species diversity of associated animals have received little attention. Here, we sampled in a subtropical seagrass-seaweed mixed bed to elucidate the effect of the macrophyte phylogenetic diversity based on the taxonomic relatedness as well as the macrophyte species diversity on species diversity of mobile epi-benthic invertebrates. Using regression analyses for each macrophyte parameter as well as multiple regression analyses, we found that the macrophyte phylogenetic diversity (taxonomic diversity index: Delta) positively influenced the invertebrate species richness and diversity index (H‧). Although the macrophyte species richness and H‧ also positively influenced the invertebrate species richness, the best fit model for invertebrate species richness did not include them, suggesting that the macrophyte species diversity indirectly influenced invertebrate species diversity. Possible explanations of the effects of macrophyte Delta on the invertebrate species diversity were the niche complementarity effect and the selection effect. This is the first study which demonstrates that macrophyte phylogenetic diversity has a strong effect on the species diversity of mobile epi-benthic invertebrates.

Computational models of epileptiform activity.

PubMed

Wendling, Fabrice; Benquet, Pascal; Bartolomei, Fabrice; Jirsa, Viktor

2016-02-15

We reviewed computer models that have been developed to reproduce and explain epileptiform activity. Unlike other already-published reviews on computer models of epilepsy, the proposed overview starts from the various types of epileptiform activity encountered during both interictal and ictal periods. Computational models proposed so far in the context of partial and generalized epilepsies are classified according to the following taxonomy: neural mass, neural field, detailed network and formal mathematical models. Insights gained about interictal epileptic spikes and high-frequency oscillations, about fast oscillations at seizure onset, about seizure initiation and propagation, about spike-wave discharges and about status epilepticus are described. This review shows the richness and complementarity of the various modeling approaches as well as the fruitful contribution of the computational neuroscience community in the field of epilepsy research. It shows that models have progressively gained acceptance and are now considered as an efficient way of integrating structural, functional and pathophysiological data about neural systems into "coherent and interpretable views". The advantages, limitations and future of modeling approaches are discussed. Perspectives in epilepsy research and clinical epileptology indicate that very promising directions are foreseen, like model-guided experiments or model-guided therapeutic strategy, among others. Copyright © 2015 Elsevier B.V. All rights reserved.

Clifford Malcolm: glimpses of his South African legacy of hope

NASA Astrophysics Data System (ADS)

Govender, Nadaraj; Ramsuran, Anitha; Dhunpath, Rubby

2008-09-01

This article reviews the contributions of Cliff Malcolm while in South Africa during the period 1997-2005. It focuses on his contribution to the fields of science education, teacher education, learner-centered education, transformational outcomes-based education and HIV/AIDS education. In this paper we provide snapshots of his work as an academic, researcher, writer and humanist as he attempted to redefine scientific literacy to acknowledge the primacy of context and culture as mediating influences on meaningful learning, especially in rural communities. We make brief reference to his use of the Foucauldian conception of power to articulate the complementarity of power and energy as an expression of agency and action, the ultimate goal of a relevant science education. An important aspect of his empirical work with research units, universities and schools, was promoting an awareness of the foundational value of learner centred education which acknowledged the child as a `collective self' rather than an `autonomous self' as derived from the Western canon. Critical of imposing Western conceptions of science on Africa, he appropriates the indigenous concept of `ubuntu,' to demonstrate the danger of dichotomising and essentialising scientific truth while simultaneously marginalising indigenous knowledges.

The Effect of Diet Mixing on a Nonselective Herbivore

PubMed Central

2016-01-01

The balanced-diet hypothesis states that a diverse prey community is beneficial to consumers due to resource complementarity among the prey species. Nonselective consumer species cannot differentiate between prey items and are therefore not able to actively regulate their diet intake. We thus wanted to test whether the balanced-diet hypothesis is applicable to nonselective consumers. We conducted a laboratory experiment in which a nonselective model grazer, the freshwater gastropod Lymnaea stagnalis, was fed benthic green algae as single species or as a multi-species mixture and quantified the snails’ somatic growth rates and shell lengths over a seven-week period. Gastropods fed the mixed diet were found to exhibit a higher somatic growth rate than the average of the snails fed single prey species. However, growth on the multi-species mixture did not exceed the growth rate obtained on the best single prey species. Similar results were obtained regarding the animals’ shell height increase over time. The mixed diet did not provide the highest growth rate, which confirms our hypothesis. We thus suggest that the balanced-diet hypothesis is less relevant for non-selective generalist consumers, which needs to be considered in estimates of secondary production. PMID:27391787

Biology and Potential Biogeochemical Impacts of Novel Predatory Flavobacteria

DTIC Science & Technology

2010-06-01

isolates to affect prey communities under more environmentally relevant conditions. An investigation of the minimum number of predatory cells needed...of present knowledge of predatory bacteria, they seem likely to affect microbial communities in ways distinct from those of protozoan grazers and...relatively less studied than both larger and smaller predators, some have been shown to affect prey communities. Much of this work has focused on the

How do different types of community commitment influence brand commitment? The mediation of brand attachment.

PubMed

Zhang, Ning; Zhou, Zhi-min; Su, Chen-ting; Zhou, Nan

2013-11-01

Although previous research indicates that participation in a brand community may foster consumer loyalty to the brand in question, research has seldom examined the mediating effect of community commitment on brand commitment. Drawing from the typologies of organizational commitment, we divide community commitment into three components: continuance community commitment (continuance CC), affective community commitment (affective CC), and normative community commitment (normative CC). We then assess the mediating role of brand attachment in the relationship between these three components and brand commitment. We test the hypotheses using a sample of online mobile phone brand communities in China. The empirical results reveal that brand attachment exerts an indirect (but not mediated) effect on the relationship between continuance CC and brand commitment and on the relationship between normative CC and brand commitment. We also find that it exerts a partial mediating effect on the relationship between affective CC and brand commitment. The findings contribute to the branding literature and have important implications for brand community management.

How Do Different Types of Community Commitment Influence Brand Commitment? The Mediation of Brand Attachment

PubMed Central

Zhang, Ning; Su, Chen-ting; Zhou, Nan

2013-01-01

Abstract Although previous research indicates that participation in a brand community may foster consumer loyalty to the brand in question, research has seldom examined the mediating effect of community commitment on brand commitment. Drawing from the typologies of organizational commitment, we divide community commitment into three components: continuance community commitment (continuance CC), affective community commitment (affective CC), and normative community commitment (normative CC). We then assess the mediating role of brand attachment in the relationship between these three components and brand commitment. We test the hypotheses using a sample of online mobile phone brand communities in China. The empirical results reveal that brand attachment exerts an indirect (but not mediated) effect on the relationship between continuance CC and brand commitment and on the relationship between normative CC and brand commitment. We also find that it exerts a partial mediating effect on the relationship between affective CC and brand commitment. The findings contribute to the branding literature and have important implications for brand community management. PMID:23768073

Ready for the Storm: Education for Disaster Risk Reduction and Climate Change Adaptation and Mitigation

ERIC Educational Resources Information Center

Kagawa, Fumiyo; Selby, David

2012-01-01

Incidences of disaster and climate change impacts are rising globally. Disaster risk reduction and climate change education are two educational responses to present and anticipated increases in the severity and frequency of hazards. They share significant complementarities and potential synergies, the latter as yet largely unexploited. Three…

C60 Recognition from Extended Tetrathiafulvalene Bis-acetylide Platinum(II) Complexes.

PubMed

Bastien, Guillaume; Dron, Paul I; Vincent, Manon; Canevet, David; Allain, Magali; Goeb, Sébastien; Sallé, Marc

2016-11-18

The favorable spatial organization imposed by the square planar 4,4'-di(tert-butyl)-2,2'-bipyridine (dbbpy) platinum(II) complex associated with the electronic and shape complementarity of π-extended tetrathiafulvalene derivatives (exTTF) toward fullerenes is usefully exploited to construct molecular tweezers, which display good affinities for C 60 .

Tracking Learners' Progress: Adopting a Dual "Corpus cum Experimental Data" Approach

ERIC Educational Resources Information Center

Meunier, Fanny; Littre, Damien

2013-01-01

The article discusses the potential of combining learner corpus research with experimental studies in order to fine-tune the understanding of learner language development. It illustrates the complementarity of the two methodological approaches with data from an ongoing study of the acquisition of the English tense and aspect system by French…

Creating Synergy in Practice: Promoting Complementarity between Evidence-Based and Postmodern Approaches

ERIC Educational Resources Information Center

Jacobs, Stephanie; Kissil, Karni; Scott, Dalesa; Davey, Maureen

2010-01-01

Postmodern and evidence-based practice (EBP) are compared and contrasted with the primary aim of adapting evidence-based practice with a more flexible epistemological lens. We begin by reviewing the epistemological underpinnings of postmodern and EBP within the field of marriage and family therapy (MFT). We next discuss how these contrasting…

Photovoltaic Universal Joints: Ball-and-Socket Interfaces in Molecular Photovoltaic Cells

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

Tremblay, Noah J.; Gorodetsky, Alon A.; Cox, Marshall P.

2010-02-15

A new approach toward higher efficiency organic photovoltaic devices (OPVs) is described. Complementarity in shape between the donor (contorted hexabenzocoronene, see picture) and acceptor (buckminsterfullerene) molecules results in OPVs that perform surprisingly well. This exploitation of host-guest chemistry at the organic/organic interface demonstrates a new direction for OPV device design.

Exploring the Future of Lifelong Learning: Advocacy, Research and Footprinting

ERIC Educational Resources Information Center

Chisholm, Lynne

2013-01-01

This reflective think-tank contribution begins by comparing advocacy and research as distinct modalities of professional and social action. In practice they frequently elide and merge into one another. While alliance and complementarity between the two modalities is constructive for shaping policy and practice, it poses risks when governments and…

Planning for complementarity : an examination of the role and opportunities of first-tier and second-tier cities along the high-speed rail network in California [research brief].

DOT National Transportation Integrated Search

2012-03-01

Californias High Speed Rail (HSR) offers opportunities for positive urban transformation in station cities, but the economic, urban design, real estate, and municipal behavior variables that may influence such change are understudied. This researc...

Pedagogical Self-Image Is the Key to Better Student-Teacher Interaction.

ERIC Educational Resources Information Center

Danahy, Michael

Imagery and metaphors for language teaching, language teachers, and language students that appear in the literature of language teacher training do not reflect a sense of mutual teacher-student cooperation or complementarity, but may instead show why most second language students seldom achieve more than minimal language proficiency. Terminology…

Assimilation of active and passive microwave observations for improved estimates of soil moisture and crop growth

USDA-ARS?s Scientific Manuscript database

An Ensemble Kalman Filter-based data assimilation framework that links a crop growth model with active and passive (AP) microwave models was developed to improve estimates of soil moisture (SM) and vegetation biomass over a growing season of soybean. Complementarities in AP observations were incorpo...

Seeing & Feeling How Enzymes Work Using Tangible Models

ERIC Educational Resources Information Center

Lau, Kwok-chi

2013-01-01

This article presents a tangible model used to help students tackle some misconceptions about enzyme actions, particularly the induced-fit model, enzyme-substrate complementarity, and enzyme inhibition. The model can simulate how substrates induce a change in the shape of the active site and the role of attraction force during enzyme-substrate…

Understanding the Difficulties Hindering Inter-Agency Collaboration for Students with Special Needs in Quebec

ERIC Educational Resources Information Center

Tetreault, Sylvie; Patenaude, David; McLaughlin, Dayna; Freeman, Andrew; Gascon, Hubert; Beaupré, Pauline; Carrière, Monique; Deschênes, Pascale Marier

2015-01-01

In 2003, the government of Quebec established the "Agreement for the Complementarity of Services Between the Health and Social Services Network and the Education Network" to define principles and obligations for inter-agency collaboration aimed at students with special needs and their families. This study documents the perspectives of…

Picturing Quantum Processes

NASA Astrophysics Data System (ADS)

Coecke, Bob; Kissinger, Aleks

2017-03-01

Preface; 1. Introduction; 2. Guide to reading this textbook; 3. Processes as diagrams; 4. String diagrams; 5. Hilbert space from diagrams; 6. Quantum processes; 7. Quantum measurement; 8. Picturing classical-quantum processes; 9. Picturing phases and complementarity; 10. Quantum theory: the full picture; 11. Quantum foundations; 12. Quantum computation; 13. Quantum resources; 14. Quantomatic; Appendix A. Some notations; References; Index.

Animal Structures and Functions, Science (Experimental): 5314.13.

ERIC Educational Resources Information Center

Silver, Barbara A.

This unit of instruction was designed to introduce the student to the relationship between structure and function in the animal kingdom, with emphasis given to: (1) the evolution of physiological systems in the major animal phyla, (2) the complementarity of structure and function, and (3) the concept of homeostasis. The booklet lists the relevant…

Digital Library and Digital Reference Service: Integration and Mutual Complementarity

ERIC Educational Resources Information Center

Liu, Jia

2008-01-01

Both the digital library and the digital reference service were invented and have been developed under the networked environment. Among their intersections, the fundamental thing is their symbiotic interest--serving the user in a more efficient way. The article starts by discussing the digital library and its service and the digital reference…

Toward a Multiple Perspective in Family Theory and Practice: The Case of Social Exchange Theory, Symbolic Interactionism, and Conflict Theory.

ERIC Educational Resources Information Center

Rank, Mark R.; LeCroy, Craig W.

1983-01-01

Examines the complementarity of three often-used theories in family research: social exchange theory, symbolic interactionism, and conflict theory. Provides a case example in which a multiple perspective is applied to a problem of marital discord. Discusses implications for the clinician. (Author/WAS)

Information-reality complementarity: The role of measurements and quantum reference frames

NASA Astrophysics Data System (ADS)

Dieguez, P. R.; Angelo, R. M.

2018-02-01

Recently, a measure has been put forward which allows for the quantification of the degree of reality of an observable for a given preparation [Bilobran and Angelo, Europhys. Lett. 112, 40005 (2015), 10.1209/0295-5075/112/40005]. Here we employ this quantifier to establish, on formal grounds, relations among the concepts of measurement, information, and physical reality. After introducing mathematical objects that unify weak and projective measurements, we study scenarios showing that an arbitrary-intensity unrevealed measurement of a given observable generally leads to an increase of its reality and also of its incompatible observables. We derive a complementarity relation connecting an amount of information associated with the apparatus with the degree of irreality of the monitored observable. Specifically for pure states, we show that the entanglement with the apparatus precisely determines the amount by which the reality of the monitored observable increases. We also point out some mechanisms whereby the irreality of an observable can be generated. Finally, using the aforementioned tools, we construct a consistent picture to address the measurement problem.

Complementarity of dark matter searches in the phenomenological MSSM

DOE PAGES

Cahill-Rowley, Matthew; Cotta, Randy; Drlica-Wagner, Alex; ...

2015-03-11

As is well known, the search for and eventual identification of dark matter in supersymmetry requires a simultaneous, multipronged approach with important roles played by the LHC as well as both direct and indirect dark matter detection experiments. We examine the capabilities of these approaches in the 19-parameter phenomenological MSSM which provides a general framework for complementarity studies of neutralino dark matter. We summarize the sensitivity of dark matter searches at the 7 and 8 (and eventually 14) TeV LHC, combined with those by Fermi, CTA, IceCube/DeepCore, COUPP, LZ and XENON. The strengths and weaknesses of each of these techniques aremore » examined and contrasted and their interdependent roles in covering the model parameter space are discussed in detail. We find that these approaches explore orthogonal territory and that advances in each are necessary to cover the supersymmetric weakly interacting massive particle parameter space. We also find that different experiments have widely varying sensitivities to the various dark matter annihilation mechanisms, some of which would be completely excluded by null results from these experiments.« less

Coevolution at protein complex interfaces can be detected by the complementarity trace with important impact for predictive docking

PubMed Central

Madaoui, Hocine; Guerois, Raphaël

2008-01-01

Protein surfaces are under significant selection pressure to maintain interactions with their partners throughout evolution. Capturing how selection pressure acts at the interfaces of protein–protein complexes is a fundamental issue with high interest for the structural prediction of macromolecular assemblies. We tackled this issue under the assumption that, throughout evolution, mutations should minimally disrupt the physicochemical compatibility between specific clusters of interacting residues. This constraint drove the development of the so-called Surface COmplementarity Trace in Complex History score (SCOTCH), which was found to discriminate with high efficiency the structure of biological complexes. SCOTCH performances were assessed not only with respect to other evolution-based approaches, such as conservation and coevolution analyses, but also with respect to statistically based scoring methods. Validated on a set of 129 complexes of known structure exhibiting both permanent and transient intermolecular interactions, SCOTCH appears as a robust strategy to guide the prediction of protein–protein complex structures. Of particular interest, it also provides a basic framework to efficiently track how protein surfaces could evolve while keeping their partners in contact. PMID:18511568

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

Tamrin, Mohd Izzuddin Mohd; Turaev, Sherzod; Sembok, Tengku Mohd Tengku

There are tremendous works in biotechnology especially in area of DNA molecules. The computer society is attempting to develop smaller computing devices through computational models which are based on the operations performed on the DNA molecules. A Watson-Crick automaton, a theoretical model for DNA based computation, has two reading heads, and works on double-stranded sequences of the input related by a complementarity relation similar with the Watson-Crick complementarity of DNA nucleotides. Over the time, several variants of Watson-Crick automata have been introduced and investigated. However, they cannot be used as suitable DNA based computational models for molecular stochastic processes andmore » fuzzy processes that are related to important practical problems such as molecular parsing, gene disease detection, and food authentication. In this paper we define new variants of Watson-Crick automata, called weighted Watson-Crick automata, developing theoretical models for molecular stochastic and fuzzy processes. We define weighted Watson-Crick automata adapting weight restriction mechanisms associated with formal grammars and automata. We also study the generative capacities of weighted Watson-Crick automata, including probabilistic and fuzzy variants. We show that weighted variants of Watson-Crick automata increase their generative power.« less

The evolutionary and ecological roots of human social organization

PubMed Central

Kaplan, Hillard S.; Hooper, Paul L.; Gurven, Michael

2009-01-01

Social organization among human foragers is characterized by a three-generational system of resource provisioning within families, long-term pair-bonding between men and women, high levels of cooperation between kin and non-kin, and relatively egalitarian social relationships. In this paper, we suggest that these core features of human sociality result from the learning- and skill-intensive human foraging niche, which is distinguished by a late age-peak in caloric production, high complementarity between male and female inputs to offspring viability, high gains to cooperation in production and risk-reduction, and a lack of economically defensible resources. We present an explanatory framework for understanding variation in social organization across human societies, highlighting the interactive effects of four key ecological and economic variables: (i) the role of skill in resource production; (ii) the degree of complementarity in male and female inputs into production; (iii) economies of scale in cooperative production and competition; and (iv) the economic defensibility of physical inputs into production. Finally, we apply this framework to understanding variation in social and political organization across foraging, horticulturalist, pastoralist and agriculturalist societies. PMID:19805435

A complementarity-determining region synthetic peptide acts as a miniantibody and neutralizes human immunodeficiency virus type 1 in vitro.

PubMed Central

Levi, M; Sällberg, M; Rudén, U; Herlyn, D; Maruyama, H; Wigzell, H; Marks, J; Wahren, B

1993-01-01

A complementarity-determining region (CDR) of the mouse monoclonal antibody (mAb) F58 was constructed with specificity to a neutralization-inducing region of human immunodeficiency virus type 1 (HIV-1). The mAb has its major reactivity to the amino acid sequence I--GPGRA in the V3 viral envelope region. All CDRs including several framework amino acids were synthesized from the sequence deduced by cloning and sequencing mAb F58 heavy- and light-chain variable domains. Peptides derived from the third heavy-chain domain (CDR-H3) alone or in combination with the other CDR sequences competed with F58 mAb for the V3 region. The CDR-H3 peptide was chemically modified by cyclization and then inhibited HIV-1 replication as well as syncytium formation by infected cells. Both the homologous IIIB viral strain to which the F58 mAb was induced and the heterologous SF2 strain were inhibited. This synthetic peptide had unexpectedly potent antiviral activity and may be a potential tool for treatment of HIV-infected persons. PMID:7685100

Sex differences in the structural connectome of the human brain.

PubMed

Ingalhalikar, Madhura; Smith, Alex; Parker, Drew; Satterthwaite, Theodore D; Elliott, Mark A; Ruparel, Kosha; Hakonarson, Hakon; Gur, Raquel E; Gur, Ruben C; Verma, Ragini

2014-01-14

Sex differences in human behavior show adaptive complementarity: Males have better motor and spatial abilities, whereas females have superior memory and social cognition skills. Studies also show sex differences in human brains but do not explain this complementarity. In this work, we modeled the structural connectome using diffusion tensor imaging in a sample of 949 youths (aged 8-22 y, 428 males and 521 females) and discovered unique sex differences in brain connectivity during the course of development. Connection-wise statistical analysis, as well as analysis of regional and global network measures, presented a comprehensive description of network characteristics. In all supratentorial regions, males had greater within-hemispheric connectivity, as well as enhanced modularity and transitivity, whereas between-hemispheric connectivity and cross-module participation predominated in females. However, this effect was reversed in the cerebellar connections. Analysis of these changes developmentally demonstrated differences in trajectory between males and females mainly in adolescence and in adulthood. Overall, the results suggest that male brains are structured to facilitate connectivity between perception and coordinated action, whereas female brains are designed to facilitate communication between analytical and intuitive processing modes.

Extending quantum mechanics entails extending special relativity

NASA Astrophysics Data System (ADS)

Aravinda, S.; Srikanth, R.

2016-05-01

The complementarity between signaling and randomness in any communicated resource that can simulate singlet statistics is generalized by relaxing the assumption of free will in the choice of measurement settings. We show how to construct an ontological extension for quantum mechanics (QMs) through the oblivious embedding of a sound simulation protocol in a Newtonian spacetime. Minkowski or other intermediate spacetimes are ruled out as the locus of the embedding by virtue of hidden influence inequalities. The complementarity transferred from a simulation to the extension unifies a number of results about quantum non-locality, and implies that special relativity has a different significance for the ontological model and for the operational theory it reproduces. Only the latter, being experimentally accessible, is required to be Lorentz covariant. There may be certain Lorentz non-covariant elements at the ontological level, but they will be inaccessible at the operational level in a valid extension. Certain arguments against the extendability of QM, due to Conway and Kochen (2009) and Colbeck and Renner (2012), are attributed to their assumption that the spacetime at the ontological level has Minkowski causal structure.

A holographic model for black hole complementarity

DOE PAGES

Lowe, David A.; Thorlacius, Larus

2016-12-07

Here, we explore a version of black hole complementarity, where an approximate semiclassical effective field theory for interior infalling degrees of freedom emerges holo-graphically from an exact evolution of exterior degrees of freedom. The infalling degrees of freedom have a complementary description in terms of outgoing Hawking radiation and must eventually decohere with respect to the exterior Hamiltonian, leading to a breakdown of the semiclassical description for an infaller. Trace distance is used to quantify the difference between the complementary time evolutions, and to define a decoherence time. We propose a dictionary where the evolution with respect to the bulkmore » effective Hamiltonian corresponds to mean field evolution in the holographic theory. In a particular model for the holographic theory, which exhibits fast scrambling, the decoherence time coincides with the scrambling time. The results support the hypothesis that decoherence of the infalling holographic state and disruptive bulk effects near the curvature singularity are comple-mentary descriptions of the same physics, which is an important step toward resolving the black hole information paradox.« less

An interactive approach based on a discrete differential evolution algorithm for a class of integer bilevel programming problems

NASA Astrophysics Data System (ADS)

Li, Hong; Zhang, Li; Jiao, Yong-Chang

2016-07-01

This paper presents an interactive approach based on a discrete differential evolution algorithm to solve a class of integer bilevel programming problems, in which integer decision variables are controlled by an upper-level decision maker and real-value or continuous decision variables are controlled by a lower-level decision maker. Using the Karush--Kuhn-Tucker optimality conditions in the lower-level programming, the original discrete bilevel formulation can be converted into a discrete single-level nonlinear programming problem with the complementarity constraints, and then the smoothing technique is applied to deal with the complementarity constraints. Finally, a discrete single-level nonlinear programming problem is obtained, and solved by an interactive approach. In each iteration, for each given upper-level discrete variable, a system of nonlinear equations including the lower-level variables and Lagrange multipliers is solved first, and then a discrete nonlinear programming problem only with inequality constraints is handled by using a discrete differential evolution algorithm. Simulation results show the effectiveness of the proposed approach.

Weighted Watson-Crick automata

NASA Astrophysics Data System (ADS)

Tamrin, Mohd Izzuddin Mohd; Turaev, Sherzod; Sembok, Tengku Mohd Tengku

2014-07-01

There are tremendous works in biotechnology especially in area of DNA molecules. The computer society is attempting to develop smaller computing devices through computational models which are based on the operations performed on the DNA molecules. A Watson-Crick automaton, a theoretical model for DNA based computation, has two reading heads, and works on double-stranded sequences of the input related by a complementarity relation similar with the Watson-Crick complementarity of DNA nucleotides. Over the time, several variants of Watson-Crick automata have been introduced and investigated. However, they cannot be used as suitable DNA based computational models for molecular stochastic processes and fuzzy processes that are related to important practical problems such as molecular parsing, gene disease detection, and food authentication. In this paper we define new variants of Watson-Crick automata, called weighted Watson-Crick automata, developing theoretical models for molecular stochastic and fuzzy processes. We define weighted Watson-Crick automata adapting weight restriction mechanisms associated with formal grammars and automata. We also study the generative capacities of weighted Watson-Crick automata, including probabilistic and fuzzy variants. We show that weighted variants of Watson-Crick automata increase their generative power.

Punishment in a complementarity game

NASA Astrophysics Data System (ADS)

Li, W.; Cai, X.; Wang, Q. A.

2006-05-01

We study the effects arisen from the punishment in an evolutionary complementarity game. Each round one member of population “buyers” deals with a randomly chosen member of population “sellers”. When the buyer's offer is greater than the seller's, a deal is done and both players are rewarded by gaining some points. Otherwise the transaction is not successful and both will lose certain points as punishment. Our simulations indicate that the resulting equilibrium of the game with punishment embedded is remarkably time-delayed compared to the counterpart of the non-punishment game. However, the median fee and the success rate of deals at the equilibrium remain nearly unchanged in various cases of games with different degrees of punishment, whether severe or not. Symmetry, between the two populations, and the equilibrium value can still be maintained when the members of both of them are punished fairly in any failed transaction. If they are done in a different manner, namely, the members of one population are subject to very severe punishment whereas their opponents receive less or no punishment at all, the latter in most cases will be better off.

The complementarity-determining region sequences in IgY antivenom hypervariable regions.

PubMed

da Rocha, David Gitirana; Fernandez, Jorge Hernandez; de Almeida, Claudia Maria Costa; da Silva, Claudia Letícia; Magnoli, Fabio Carlos; da Silva, Osmair Élder; da Silva, Wilmar Dias

2017-08-01

The data presented in this article are related to the research article entitled "Development of IgY antibodies against anti-snake toxins endowed with highly lethal neutralizing activity" (da Rocha et al., 2017) [1]. Complementarity-determining region (CDR) sequences are variable antibody (Ab) sequences that respond with specificity, duration and strength to identify and bind to antigen (Ag) epitopes. B lymphocytes isolated from hens immunized with Bitis arietans (Ba) and anti- Crotalus durissus terrificus (Cdt) venoms and expressing high specificity, affinity and toxicity neutralizing antibody titers were used as DNA sources. The VLF1, CDR1, CDR2, VLR1 and CDR3 sequences were validated by BLASTp, and values corresponding to IgY V L and V H anti-Ba or anti-Cdt venoms were identified, registered [ Gallus gallus IgY Fv Light chain (GU815099)/ Gallus gallus IgY Fv Heavy chain (GU815098)] and used for molecular modeling of IgY scFv anti-Ba. The resulting CDR1, CDR2 and CDR3 sequences were combined to construct the three - dimensional structure of the Ab paratope.

Niels Bohr's discussions with Albert Einstein, Werner Heisenberg, and Erwin Schroedinger: the origins of the principles of uncertainty and complementarity

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

Mehra, J.

1987-05-01

In this paper, the main outlines of the discussions between Niels Bohr with Albert Einstein, Werner Heisenberg, and Erwin Schroedinger during 1920-1927 are treated. From the formulation of quantum mechanics in 1925-1926 and wave mechanics in 1926, there emerged Born's statistical interpretation of the wave function in summer 1926, and on the basis of the quantum mechanical transformation theory - formulated in fall 1926 by Dirac, London, and Jordan - Heisenberg formulated the uncertainty principle in early 1927. At the Volta Conference in Como in September 1927 and at the fifth Solvay Conference in Brussels the following month, Bohr publiclymore » enunciated his complementarity principle, which had been developing in his mind for several years. The Bohr-Einstein discussions about the consistency and completeness of quantum mechanics and of physical theory as such - formally begun in October 1927 at the fifth Solvay Conference and carried on at the sixth Solvay Conference in October 1930 - were continued during the next decades. All these aspects are briefly summarized.« less

Initial fungal colonizer affects mass loss and fungal community development in Picea abies logs 6 yr after inoculation

Treesearch

Daniel L. Lindner; Rimvydas Vasaitis; Ariana Kubartova; Johan Allmer; Hanna Johannesson; Mark T. Banik; Jan. Stenlid

2011-01-01

Picea abies logs were inoculated with Resinicium bicolor, Fomitopsis pinicola or left un-inoculated and placed in an old-growth boreal forest. Mass loss and fungal community data were collected after 6 yr to test whether simplification of the fungal community via inoculation affects mass loss and fungal community development. Three...

Factors Affecting Soil Microbial Community Structure in Tomato Cropping Systems

USDA-ARS?s Scientific Manuscript database

Soil and rhizosphere microbial communities in agroecosystems may be affected by soil, climate, plant species, and management. We identified some of the most important factors controlling microbial biomass and community structure in an agroecosystem utilizing tomato plants with the following nine tre...

Plant ecophysiology and forest response to global change.

PubMed

Buchmann, N

2002-11-01

There are many ways of studying forest responses to global change. Most current national and international programs focus on net gas exchange of the terrestrial biosphere and are typically interdisciplinary, multi-scale projects. Key objectives of these programs are surprisingly similar to those of classical plant ecophysiology studies, i.e., to explore functional relationships of plant or plant community responses to environmental change. Thus, common research questions that link plant ecophysiology to ecosystem functioning can be identified for both research communities, promising complementarity and synergism for joint research projects. Although some well-established ecophysiological relationships, such as light responses or stomatal limitations of photosynthetic gas exchange, are currently employed in many ecosystem-scale net flux studies for gap-filling or modeling, only 14% (n = 27) of all eddy covariance flux studies in forests (n = 196; published between 1992 and April 2002) include plant ecophysiological measurements (n = 24) or biomass and growth estimates (n = 8). Generally, emphasis is on CO2 exchange measurements at various scales (foliage, shoots, branches; n = 14) and water relations measurements (n = 11). These measurements do not fully support the typical parameterization of stand and regional models, which often need information on canopy architecture and nitrogen nutrition. By means of a complementary research approach, valuable information can be acquired that is unobtainable by means of a single approach. This additional information is important for the identification of underlying biotic and environmental drivers, for the regulation of net ecosystem fluxes and their partitioning, and the independent validation of measured net ecosystem fluxes. Thus, combining micrometeorology and ecophysiology at flux sites is strongly recommended for ecosystem functioning studies.

Protein-Protein Interaction Site Predictions with Three-Dimensional Probability Distributions of Interacting Atoms on Protein Surfaces

PubMed Central

Chen, Ching-Tai; Peng, Hung-Pin; Jian, Jhih-Wei; Tsai, Keng-Chang; Chang, Jeng-Yih; Yang, Ei-Wen; Chen, Jun-Bo; Ho, Shinn-Ying; Hsu, Wen-Lian; Yang, An-Suei

2012-01-01

Protein-protein interactions are key to many biological processes. Computational methodologies devised to predict protein-protein interaction (PPI) sites on protein surfaces are important tools in providing insights into the biological functions of proteins and in developing therapeutics targeting the protein-protein interaction sites. One of the general features of PPI sites is that the core regions from the two interacting protein surfaces are complementary to each other, similar to the interior of proteins in packing density and in the physicochemical nature of the amino acid composition. In this work, we simulated the physicochemical complementarities by constructing three-dimensional probability density maps of non-covalent interacting atoms on the protein surfaces. The interacting probabilities were derived from the interior of known structures. Machine learning algorithms were applied to learn the characteristic patterns of the probability density maps specific to the PPI sites. The trained predictors for PPI sites were cross-validated with the training cases (consisting of 432 proteins) and were tested on an independent dataset (consisting of 142 proteins). The residue-based Matthews correlation coefficient for the independent test set was 0.423; the accuracy, precision, sensitivity, specificity were 0.753, 0.519, 0.677, and 0.779 respectively. The benchmark results indicate that the optimized machine learning models are among the best predictors in identifying PPI sites on protein surfaces. In particular, the PPI site prediction accuracy increases with increasing size of the PPI site and with increasing hydrophobicity in amino acid composition of the PPI interface; the core interface regions are more likely to be recognized with high prediction confidence. The results indicate that the physicochemical complementarity patterns on protein surfaces are important determinants in PPIs, and a substantial portion of the PPI sites can be predicted correctly with the physicochemical complementarity features based on the non-covalent interaction data derived from protein interiors. PMID:22701576

DARC 2.0: Improved Docking and Virtual Screening at Protein Interaction Sites

PubMed Central

Gowthaman, Ragul; Lyskov, Sergey; Karanicolas, John

2015-01-01

Over the past decade, protein-protein interactions have emerged as attractive but challenging targets for therapeutic intervention using small molecules. Due to the relatively flat surfaces that typify protein interaction sites, modern virtual screening tools developed for optimal performance against “traditional” protein targets perform less well when applied instead at protein interaction sites. Previously, we described a docking method specifically catered to the shallow binding modes characteristic of small-molecule inhibitors of protein interaction sites. This method, called DARC (Docking Approach using Ray Casting), operates by comparing the topography of the protein surface when “viewed” from a vantage point inside the protein against the topography of a bound ligand when “viewed” from the same vantage point. Here, we present five key enhancements to DARC. First, we use multiple vantage points to more accurately determine protein-ligand surface complementarity. Second, we describe a new scheme for rapidly determining optimal weights in the DARC scoring function. Third, we incorporate sampling of ligand conformers “on-the-fly” during docking. Fourth, we move beyond simple shape complementarity and introduce a term in the scoring function to capture electrostatic complementarity. Finally, we adjust the control flow in our GPU implementation of DARC to achieve greater speedup of these calculations. At each step of this study, we evaluate the performance of DARC in a “pose recapitulation” experiment: predicting the binding mode of 25 inhibitors each solved in complex with its distinct target protein (a protein interaction site). Whereas the previous version of DARC docked only one of these inhibitors to within 2 Å RMSD of its position in the crystal structure, the newer version achieves this level of accuracy for 12 of the 25 complexes, corresponding to a statistically significant performance improvement (p < 0.001). Collectively then, we find that the five enhancements described here – which together make up DARC 2.0 – lead to dramatically improved speed and performance relative to the original DARC method. PMID:26181386

Phylodiversity to inform conservation policy: An Australian example.

PubMed

Laity, Tania; Laffan, Shawn W; González-Orozco, Carlos E; Faith, Daniel P; Rosauer, Dan F; Byrne, Margaret; Miller, Joseph T; Crayn, Darren; Costion, Craig; Moritz, Craig C; Newport, Karl

2015-11-15

Phylodiversity measures summarise the phylogenetic diversity patterns of groups of organisms. By using branches of the tree of life, rather than its tips (e.g., species), phylodiversity measures provide important additional information about biodiversity that can improve conservation policy and outcomes. As a biodiverse nation with a strong legislative and policy framework, Australia provides an opportunity to use phylogenetic information to inform conservation decision-making. We explored the application of phylodiversity measures across Australia with a focus on two highly biodiverse regions, the south west of Western Australia (SWWA) and the South East Queensland bioregion (SEQ). We analysed seven diverse groups of organisms spanning five separate phyla on the evolutionary tree of life, the plant genera Acacia and Daviesia, mammals, hylid frogs, myobatrachid frogs, passerine birds, and camaenid land snails. We measured species richness, weighted species endemism (WE) and two phylodiversity measures, phylogenetic diversity (PD) and phylogenetic endemism (PE), as well as their respective complementarity scores (a measure of gains and losses) at 20 km resolution. Higher PD was identified within SEQ for all fauna groups, whereas more PD was found in SWWA for both plant groups. PD and PD complementarity were strongly correlated with species richness and species complementarity for most groups but less so for plants. PD and PE were found to complement traditional species-based measures for all groups studied: PD and PE follow similar spatial patterns to richness and WE, but highlighted different areas that would not be identified by conventional species-based biodiversity analyses alone. The application of phylodiversity measures, particularly the novel weighted complementary measures considered here, in conservation can enhance protection of the evolutionary history that contributes to present day biodiversity values of areas. Phylogenetic measures in conservation can include important elements of biodiversity in conservation planning, such as evolutionary potential and feature diversity that will improve decision-making and lead to better biodiversity conservation outcomes. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Communication, Correlation and Complementarity

NASA Astrophysics Data System (ADS)

Schumacher, Benjamin Wade

1990-01-01

In quantum communication, a sender prepares a quantum system in a state corresponding to his message and conveys it to a receiver, who performs a measurement on it. The receiver acquires information about the message based on the outcome of his measurement. Since the state of a single quantum system is not always completely determinable from measurement, quantum mechanics limits the information capacity of such channels. According to a theorem of Kholevo, the amount of information conveyed by the channel can be no greater than the entropy of the ensemble of possible physical signals. The connection between information and entropy allows general theorems to be proved regarding the energy requirements of communication. For example, it can be shown that one particular quantum coding scheme, called thermal coding, uses energy with maximum efficiency. A close analogy between communication and quantum correlation can be made using Everett's notion of relative states. Kholevo's theorem can be used to prove that the mutual information of a pair of observables on different systems is bounded by the entropy of the state of each system. This confirms and extends an old conjecture of Everett. The complementarity of quantum observables can be described by information-theoretic uncertainty relations, several of which have been previously derived. These relations imply limits on the degree to which different messages can be coded in complementary observables of a single channel. Complementarity also restricts the amount of information that can be recovered from a given channel using a given decoding observable. Information inequalities can be derived which are analogous to the well-known Bell inequalities for correlated quantum systems. These inequalities are satisfied for local hidden variable theories but are violated by quantum systems, even where the correlation is weak. These information inequalities are metric inequalities for an "information distance", and their structure can be made exactly analogous to that of the familiar covariance Bell inequalities by introducing a "covariance distance". Similar inequalities derived for successive measurements on a single system are also violated in quantum mechanics.

Challenges to Superfund Community Nutrition Programs in Kentucky

PubMed Central

Gaetke, Lisa; Gaetke, Kara; Bowen, Christa

2008-01-01

Since 2000, the University of Kentucky's (UK's) Superfund Basic Research Program (SBRP) Community Outreach Core has provided support and guidance through Superfund Community Action through Nutrition (SCAN) programs, which meet the needs of individuals and communities affected by environmental contaminants. It has been shown that nutrition may modulate the toxicity of Superfund chemicals. SCAN programs integrate nutrition education, nutrition science research, and health communication to increase understanding of health risks associated with residing near Superfund sites. Two critical tasks must be accomplished. SCAN personnel must identify and recruit affected community members, and then, offer meaningful programs. Certain quantitative outcome measures and legal issues presented both challenges and opportunities. Community members preferred qualitative evaluation discussions, which showed increased knowledge and improved attitudes following SCAN programs. SCAN, in full partnership with affected communities, translates safe, effective nutrition information to reduce health risks associated with exposure to Superfund pollutants. PMID:18443657

Challenges to superfund community nutrition programs in kentucky.

PubMed

Gaetke, Lisa; Gaetke, Kara; Bowen, Christa

2008-03-01

Since 2000, the University of Kentucky's (UK's) Superfund Basic Research Program (SBRP) Community Outreach Core has provided support and guidance through Superfund Community Action through Nutrition (SCAN) programs, which meet the needs of individuals and communities affected by environmental contaminants. It has been shown that nutrition may modulate the toxicity of Superfund chemicals. SCAN programs integrate nutrition education, nutrition science research, and health communication to increase understanding of health risks associated with residing near Superfund sites. Two critical tasks must be accomplished. SCAN personnel must identify and recruit affected community members, and then, offer meaningful programs. Certain quantitative outcome measures and legal issues presented both challenges and opportunities. Community members preferred qualitative evaluation discussions, which showed increased knowledge and improved attitudes following SCAN programs. SCAN, in full partnership with affected communities, translates safe, effective nutrition information to reduce health risks associated with exposure to Superfund pollutants.

Communities needs, values, and representations of the world: lessons learned from Greenland's and Senegal's ARTisticc's study sites.

NASA Astrophysics Data System (ADS)

Baztan, J.; Vanderlinden, J. P.; Cordier, M.; Da Cunha, C.; Gaye, N.; Huctin, J. M.; Kane, A.; Quensiere, J.; Remvikos, Y.; Seck, A.

2016-12-01

The cultural dimensions of climate change impacts and adaptation have been increasingly examined in recent years through various disciplinary lenses, exposing a clear need for mainstream natural sciences to address the question of how to incorporate the values of communities facing global changes into their work. With this in mind, the work presented here addresses three main questions: (i) Do community members consider available scientific data and findings credible? Answering this question provides insight into whether available scientific knowledge expresses causal links that are mobilized by affected communities. (ii) Do community members consider available scientific data and findings salient? Answering this question provides insight into whether available scientific knowledge focuses on phenomena that those in affected communities think should receive attention. (iii) Do community members consider available scientific data and findings legitimate? Answering this question provides insight into whether available scientific knowledge expresses what is good, tolerable, and/or acceptable for affected communities. These three questions delve into the ways in which adaptation requires affected individuals and communities to adopt attitudes by integrating/woven from potentially conflicting evidence, relevance, and/or normative claims. These questions also shed light on the links between mainstream sciences and studied affected communities. The research presented here focuses on 2 communities: (i) Uummannaq, an island of 12km2 in a fjord, located along the middle of Greenland's west coast and (ii) Joal-Fadiouth & M'bour area in the wester African's coast, few Km south of Dakar, Senegal. This communication shares the results from field work experiences from ARTiticc's interdisciplinary approach to identifying the needs, values, and representations of the world of the communities, and how to fit these elements into mainstream sciences in order to bridge gaps between communities and research efforts and by doing so, determine the optimal adaptation strategies through which to engage global changes.

Plant domestication and the assembly of bacterial and fungal communities associated with strains of the common sunflower, Helianthus annuus.

PubMed

Leff, Jonathan W; Lynch, Ryan C; Kane, Nolan C; Fierer, Noah

2017-04-01

Root and rhizosphere microbial communities can affect plant health, but it remains undetermined how plant domestication may influence these bacterial and fungal communities. We grew 33 sunflower (Helianthus annuus) strains (n = 5) that varied in their extent of domestication and assessed rhizosphere and root endosphere bacterial and fungal communities. We also assessed fungal communities in the sunflower seeds to investigate the degree to which root and rhizosphere communities were influenced by vertical transmission of the microbiome through seeds. Neither root nor rhizosphere bacterial communities were affected by the extent of sunflower domestication, but domestication did affect the composition of rhizosphere fungal communities. In particular, more modern sunflower strains had lower relative abundances of putative fungal pathogens. Seed-associated fungal communities strongly differed across strains, but several lines of evidence suggest that there is minimal vertical transmission of fungi from seeds to the adult plants. Our results indicate that plant-associated fungal communities are more strongly influenced by host genetic factors and plant breeding than bacterial communities, a finding that could influence strategies for optimizing microbial communities to improve crop yields. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

The interacting roles of climate, soils, and plant production on soil microbial communities at a continental scale

USGS Publications Warehouse

Waldrop, Mark P.; Holloway, JoAnn M.; Smith, David; Goldhaber, Martin B.; Drenovsky, R.E.; Scow, K.M.; Dick, R.; Howard, Daniel M.; Wylie, Bruce K.; Grace, James B.

2017-01-01

Soil microbial communities control critical ecosystem processes such as decomposition, nutrient cycling, and soil organic matter formation. Continental scale patterns in the composition and functioning of microbial communities are related to climatic, biotic, and edaphic factors such as temperature and precipitation, plant community composition, and soil carbon, nitrogen, and pH. Although these relationships have been well explored individually, the examination of the factors that may act directly on microbial communities vs. those that may act indirectly through other ecosystem properties has not been well developed. To further such understanding, we utilized structural equation modeling (SEM) to evaluate a set of hypotheses about the direct and indirect effects of climatic, biotic, and edaphic variables on microbial communities across the continental United States. The primary goals of this work were to test our current understanding of the interactions among climate, soils, and plants in affecting microbial community composition, and to examine whether variation in the composition of the microbial community affects potential rates of soil enzymatic activities. A model of interacting factors created through SEM shows several expected patterns. Distal factors such as climate had indirect effects on microbial communities by influencing plant productivity, soil mineralogy, and soil pH, but factors related to soil organic matter chemistry had the most direct influence on community composition. We observed that both plant productivity and soil mineral composition were important indirect influences on community composition at the continental scale, both interacting to affect organic matter content and microbial biomass and ultimately community composition. Although soil hydrolytic enzymes were related to the moisture regime and soil carbon, oxidative enzymes were also affected by community composition, reflected in the abundance of soil fungi. These results highlight that soil microbial communities can be modeled within the context of multiple interacting ecosystem properties acting both directly and indirectly on their composition and function, and this provides a rich and informative context with which to examine communities. This work also highlights that variation in climate, microbial biomass, and microbial community composition can affect maximum rates of soil enzyme activities, potentially influencing rates of decomposition and nutrient mineralization in soils.

Compliant contact versus rigid contact: A comparison in the context of granular dynamics

NASA Astrophysics Data System (ADS)

Pazouki, Arman; Kwarta, Michał; Williams, Kyle; Likos, William; Serban, Radu; Jayakumar, Paramsothy; Negrut, Dan

2017-10-01

We summarize and numerically compare two approaches for modeling and simulating the dynamics of dry granular matter. The first one, the discrete-element method via penalty (DEM-P), is commonly used in the soft matter physics and geomechanics communities; it can be traced back to the work of Cundall and Strack [P. Cundall, Proc. Symp. ISRM, Nancy, France 1, 129 (1971); P. Cundall and O. Strack, Geotechnique 29, 47 (1979), 10.1680/geot.1979.29.1.47]. The second approach, the discrete-element method via complementarity (DEM-C), considers the grains perfectly rigid and enforces nonpenetration via complementarity conditions; it is commonly used in robotics and computer graphics applications and had two strong promoters in Moreau and Jean [J. J. Moreau, in Nonsmooth Mechanics and Applications, edited by J. J. Moreau and P. D. Panagiotopoulos (Springer, Berlin, 1988), pp. 1-82; J. J. Moreau and M. Jean, Proceedings of the Third Biennial Joint Conference on Engineering Systems and Analysis, Montpellier, France, 1996, pp. 201-208]. The DEM-P and DEM-C are manifestly unlike each other: They use different (i) approaches to model the frictional contact problem, (ii) sets of model parameters to capture the physics of interest, and (iii) classes of numerical methods to solve the differential equations that govern the dynamics of the granular material. Herein, we report numerical results for five experiments: shock wave propagation, cone penetration, direct shear, triaxial loading, and hopper flow, which we use to compare the DEM-P and DEM-C solutions. This exercise helps us reach two conclusions. First, both the DEM-P and DEM-C are predictive, i.e., they predict well the macroscale emergent behavior by capturing the dynamics at the microscale. Second, there are classes of problems for which one of the methods has an advantage. Unlike the DEM-P, the DEM-C cannot capture shock-wave propagation through granular media. However, the DEM-C is proficient at handling arbitrary grain geometries and solves, at large integration step sizes, smaller problems, i.e., containing thousands of elements, very effectively. The DEM-P vs DEM-C comparison is carried out using a public-domain, open-source software package; the models used are available online.

Compliant contact versus rigid contact: A comparison in the context of granular dynamics.

PubMed

Pazouki, Arman; Kwarta, Michał; Williams, Kyle; Likos, William; Serban, Radu; Jayakumar, Paramsothy; Negrut, Dan

2017-10-01

We summarize and numerically compare two approaches for modeling and simulating the dynamics of dry granular matter. The first one, the discrete-element method via penalty (DEM-P), is commonly used in the soft matter physics and geomechanics communities; it can be traced back to the work of Cundall and Strack [P. Cundall, Proc. Symp. ISRM, Nancy, France 1, 129 (1971); P. Cundall and O. Strack, Geotechnique 29, 47 (1979)GTNQA80016-850510.1680/geot.1979.29.1.47]. The second approach, the discrete-element method via complementarity (DEM-C), considers the grains perfectly rigid and enforces nonpenetration via complementarity conditions; it is commonly used in robotics and computer graphics applications and had two strong promoters in Moreau and Jean [J. J. Moreau, in Nonsmooth Mechanics and Applications, edited by J. J. Moreau and P. D. Panagiotopoulos (Springer, Berlin, 1988), pp. 1-82; J. J. Moreau and M. Jean, Proceedings of the Third Biennial Joint Conference on Engineering Systems and Analysis, Montpellier, France, 1996, pp. 201-208]. The DEM-P and DEM-C are manifestly unlike each other: They use different (i) approaches to model the frictional contact problem, (ii) sets of model parameters to capture the physics of interest, and (iii) classes of numerical methods to solve the differential equations that govern the dynamics of the granular material. Herein, we report numerical results for five experiments: shock wave propagation, cone penetration, direct shear, triaxial loading, and hopper flow, which we use to compare the DEM-P and DEM-C solutions. This exercise helps us reach two conclusions. First, both the DEM-P and DEM-C are predictive, i.e., they predict well the macroscale emergent behavior by capturing the dynamics at the microscale. Second, there are classes of problems for which one of the methods has an advantage. Unlike the DEM-P, the DEM-C cannot capture shock-wave propagation through granular media. However, the DEM-C is proficient at handling arbitrary grain geometries and solves, at large integration step sizes, smaller problems, i.e., containing thousands of elements, very effectively. The DEM-P vs DEM-C comparison is carried out using a public-domain, open-source software package; the models used are available online.

The Influence of Community Context on How Coalitions Achieve HIV-Preventive Structural Change

ERIC Educational Resources Information Center

Reed, Sarah J.; Miller, Robin Lin; Francisco, Vincent T.

2014-01-01

Community coalition action theory (CCAT) depicts the processes and factors that affect coalition formation, maintenance, institutionalization, actions, and outcomes. CCAT proposes that community context affects coalitions at every phase of development and operation. We analyzed data from 12 "Connect to Protect" coalitions using inductive…

Conflict, Development and Community Participation in Education: Pakistan and Yemen

ERIC Educational Resources Information Center

Jones, Adele

2005-01-01

In development policy, community participation has increasingly come to be seen as a way to encourage community interest, involvement, ownership and ultimately, sustainability of projects. Education has also been affected by this discourse. The following paper examines two countries affected by conflict (Pakistan and Yemen), asking what type of…

How stock of origin affects performance of individuals across a meta-ecosystem: an example from sockeye salmon.

PubMed

Griffiths, Jennifer R; Schindler, Daniel E; Seeb, Lisa W

2013-01-01

Connectivity among diverse habitats can buffer populations from adverse environmental conditions, influence the functioning of meta-ecosystems, and ultimately affect the reliability of ecosystem services. This stabilizing effect on populations is proposed to derive from complementarity in growth and survival conditions experienced by individuals in the different habitats that comprise meta-ecosystems. Here we use the fine scale differentiation of salmon populations between diverse lake habitats to assess how rearing habitat and stock of origin affect the body condition of juvenile sockeye salmon. We use genetic markers (single nucleotide polymorphisms) to assign individuals of unknown origin to stock group and in turn characterize ecologically relevant attributes across habitats and stocks. Our analyses show that the body condition of juvenile salmon is related to the productivity of alternative habitats across the watershed, irrespective of their stock of origin. Emigrants and residents with genetic origins in the high productivity lake were also differentiated by their body condition, poor and high respectively. These emigrants represented a substantial proportion of juvenile sockeye salmon rearing in the lower productivity lake habitat. Despite emigrants originating from the more productive lake, they did not differ in body condition from the individuals spawned in the lower productivity, recipient habitat. Genetic tools allowed us to assess the performance of different stocks groups across the diverse habitats comprising their meta-ecosystem. The ability to characterize the ecological consequences of meta-ecosystem connectivity can help develop strategies to protect and restore ecosystems and the services they provide to humans.

How Stock of Origin Affects Performance of Individuals across a Meta-Ecosystem: An Example from Sockeye Salmon

PubMed Central

Griffiths, Jennifer R.; Schindler, Daniel E.; Seeb, Lisa W.

2013-01-01

Connectivity among diverse habitats can buffer populations from adverse environmental conditions, influence the functioning of meta-ecosystems, and ultimately affect the reliability of ecosystem services. This stabilizing effect on populations is proposed to derive from complementarity in growth and survival conditions experienced by individuals in the different habitats that comprise meta-ecosystems. Here we use the fine scale differentiation of salmon populations between diverse lake habitats to assess how rearing habitat and stock of origin affect the body condition of juvenile sockeye salmon. We use genetic markers (single nucleotide polymorphisms) to assign individuals of unknown origin to stock group and in turn characterize ecologically relevant attributes across habitats and stocks. Our analyses show that the body condition of juvenile salmon is related to the productivity of alternative habitats across the watershed, irrespective of their stock of origin. Emigrants and residents with genetic origins in the high productivity lake were also differentiated by their body condition, poor and high respectively. These emigrants represented a substantial proportion of juvenile sockeye salmon rearing in the lower productivity lake habitat. Despite emigrants originating from the more productive lake, they did not differ in body condition from the individuals spawned in the lower productivity, recipient habitat. Genetic tools allowed us to assess the performance of different stocks groups across the diverse habitats comprising their meta-ecosystem. The ability to characterize the ecological consequences of meta-ecosystem connectivity can help develop strategies to protect and restore ecosystems and the services they provide to humans. PMID:23505539

Toxic effect of two kinds of mineral collectors on soil microbial richness and activity: analysis by microcalorimetry, microbial count, and enzyme activity assay.

PubMed

Bararunyeretse, Prudence; Yao, Jun; Dai, Yunrong; Bigawa, Samuel; Guo, Zunwei; Zhu, Mijia

2017-01-01

Flotation reagents are hugely and increasingly used in mining and other industrial and economic activities from which an important part is discharged into the environment. China could be the most affected country by the resulting pollution. However, their ecotoxicological dimension is still less addressed and understood. This study aimed to analyze the toxic effect of sodium isobutyl xanthate (SIBX) and sodium isopropyl xanthate (SIPX) to soil microbial richness and activity and to make a comparison between the two compounds in regard to their effects on soil microbial and enzymes activities. Different methods, including microcalorimetry, viable cell counts, cell density, and catalase and fluorescein diacetate (FDA) hydrololase activities measurement, were applied. The two chemicals exhibited a significant inhibitory effect (P < 0.05 or P < 0.01) to all parameters, SIPX being more adverse than SIBX. As the doses of SIBX and SIPX increased from 5 to 300 μg g -1 soil, their inhibitory ratio ranged from 4.84 to 45.16 % and from 16.13 to 69.68 %, respectively. All parameters fluctuated with the incubation time (10-day period). FDA hydrolysis was more directly affected but was relatively more resilient than catalase activity. Potential changes of those chemicals in the experimental media and complementarity between experimental techniques were justified.

Toward a community ecology of landscapes: predicting multiple predator-prey interactions across geographic space.

PubMed

Schmitz, Oswald J; Miller, Jennifer R B; Trainor, Anne M; Abrahms, Briana

2017-09-01

Community ecology was traditionally an integrative science devoted to studying interactions between species and their abiotic environments in order to predict species' geographic distributions and abundances. Yet for philosophical and methodological reasons, it has become divided into two enterprises: one devoted to local experimentation on species interactions to predict community dynamics; the other devoted to statistical analyses of abiotic and biotic information to describe geographic distribution. Our goal here is to instigate thinking about ways to reconnect the two enterprises and thereby return to a tradition to do integrative science. We focus specifically on the community ecology of predators and prey, which is ripe for integration. This is because there is active, simultaneous interest in experimentally resolving the nature and strength of predator-prey interactions as well as explaining patterns across landscapes and seascapes. We begin by describing a conceptual theory rooted in classical analyses of non-spatial food web modules used to predict species interactions. We show how such modules can be extended to consideration of spatial context using the concept of habitat domain. Habitat domain describes the spatial extent of habitat space that predators and prey use while foraging, which differs from home range, the spatial extent used by an animal to meet all of its daily needs. This conceptual theory can be used to predict how different spatial relations of predators and prey could lead to different emergent multiple predator-prey interactions such as whether predator consumptive or non-consumptive effects should dominate, and whether intraguild predation, predator interference or predator complementarity are expected. We then review the literature on studies of large predator-prey interactions that make conclusions about the nature of multiple predator-prey interactions. This analysis reveals that while many studies provide sufficient information about predator or prey spatial locations, and thus meet necessary conditions of the habitat domain conceptual theory for drawing conclusions about the nature of the predator-prey interactions, several studies do not. We therefore elaborate how modern technology and statistical approaches for animal movement analysis could be used to test the conceptual theory, using experimental or quasi-experimental analyses at landscape scales. © 2017 by the Ecological Society of America.

Allelic polymorphism in the T cell receptor and its impact on immune responses.

PubMed

Gras, Stephanie; Chen, Zhenjun; Miles, John J; Liu, Yu Chih; Bell, Melissa J; Sullivan, Lucy C; Kjer-Nielsen, Lars; Brennan, Rebekah M; Burrows, Jacqueline M; Neller, Michelle A; Khanna, Rajiv; Purcell, Anthony W; Brooks, Andrew G; McCluskey, James; Rossjohn, Jamie; Burrows, Scott R

2010-07-05

In comparison to human leukocyte antigen (HLA) polymorphism, the impact of allelic sequence variation within T cell receptor (TCR) loci is much less understood. Particular TCR loci have been associated with autoimmunity, but the molecular basis for this phenomenon is undefined. We examined the T cell response to an HLA-B*3501-restricted epitope (HPVGEADYFEY) from Epstein-Barr virus (EBV), which is frequently dominated by a TRBV9*01(+) public TCR (TK3). However, the common allelic variant TRBV9*02, which differs by a single amino acid near the CDR2beta loop (Gln55-->His55), was never used in this response. The structure of the TK3 TCR, its allelic variant, and a nonnaturally occurring mutant (Gln55-->Ala55) in complex with HLA-B*3501(HPVGEADYFEY) revealed that the Gln55-->His55 polymorphism affected the charge complementarity at the TCR-peptide-MHC interface, resulting in reduced functional recognition of the cognate and naturally occurring variants of this EBV peptide. Thus, polymorphism in the TCR loci may contribute toward variability in immune responses and the outcome of infection.

Consistent effects of biodiversity loss on multifunctionality across contrasting ecosystems.

PubMed

Fanin, Nicolas; Gundale, Michael J; Farrell, Mark; Ciobanu, Marcel; Baldock, Jeff A; Nilsson, Marie-Charlotte; Kardol, Paul; Wardle, David A

2018-02-01

Understanding how loss of biodiversity affects ecosystem functioning, and thus the delivery of ecosystem goods and services, has become increasingly necessary in a changing world. Considerable recent attention has focused on predicting how biodiversity loss simultaneously impacts multiple ecosystem functions (that is, ecosystem multifunctionality), but the ways in which these effects vary across ecosystems remain unclear. Here, we report the results of two 19-year plant diversity manipulation experiments, each established across a strong environmental gradient. Although the effects of plant and associated fungal diversity loss on individual functions frequently differed among ecosystems, the consequences of biodiversity loss for multifunctionality were relatively invariant. However, the context-dependency of biodiversity effects also worked in opposing directions for different individual functions, meaning that similar multifunctionality values across contrasting ecosystems could potentially mask important differences in the effects of biodiversity on functioning among ecosystems. Our findings highlight that an understanding of the relative contribution of species or functional groups to individual ecosystem functions among contrasting ecosystems and their interactions (that is, complementarity versus competition) is critical for guiding management efforts aimed at maintaining ecosystem multifunctionality and the delivery of multiple ecosystem services.

Effects of protein engineering and rational mutagenesis on crystal lattice of single chain antibody fragments

PubMed Central

Kalyoncu, Sibel; Hyun, Jeongmin; Pai, Jennifer C.; Johnson, Jennifer L.; Entzminger, Kevin; Jain, Avni; Heaner, David P.; Morales, Ivan A.; Truskett, Thomas M.; Maynard, Jennifer A.; Lieberman, Raquel L.

2014-01-01

Protein crystallization is dependent upon, and sensitive to, the intermolecular contacts that assist in ordering proteins into a three dimensional lattice. Here we used protein engineering and mutagenesis to affect the crystallization of single chain antibody fragments (scFvs) that recognize the EE epitope (EYMPME) with high affinity. These hypercrystallizable scFvs are under development to assist difficult proteins, such as membrane proteins, in forming crystals, by acting as crystallization chaperones. Guided by analyses of intermolecular crystal lattice contacts, two second-generation anti-EE scFvs were produced, which bind to proteins with installed EE tags. Surprisingly, although non-complementarity determining region (CDR) lattice residues from the parent scFv framework remained unchanged through the processes of protein engineering and rational design, crystal lattices of the derivative scFvs differ. Comparison of energy calculations and the experimentally-determined lattice interactions for this basis set provides insight into the complexity of the forces driving crystal lattice choice and demonstrates the availability of multiple well-ordered surface features in our scFvs capable of forming versatile crystal contacts. PMID:24615866

Investigating the association between social interactions and personality states dynamics

PubMed Central

Finnerty, Ailbhe N.; Staiano, Jacopo; Teso, Stefano; Passerini, Andrea; Pianesi, Fabio; Lepri, Bruno

2017-01-01

The recent personality psychology literature has coined the name of personality states to refer to states having the same behavioural, affective and cognitive content (described by adjectives) as the corresponding trait, but for a shorter duration. The variability in personality states may be the reaction to specific characteristics of situations. The aim of our study is to investigate whether specific situational factors, that is, different configurations of face-to-face interactions, are predictors of variability of personality states in a work environment. The obtained results provide evidence that within-person variability in personality is associated with variation in face-to-face interactions. Interestingly, the effects differ by type and level of the personality states: adaptation effects for Agreeableness and Emotional Stability, whereby the personality states of an individual trigger similar states in other people interacting with them and complementarity effects for Openness to Experience, whereby the personality states of an individual trigger opposite states in other people interacting with them. Overall, these findings encourage further research to characterize face-to-face and social interactions in terms of their relevance to personality states. PMID:28989732

A Targeted Oligonucleotide Enhancer of SMN2 Exon 7 Splicing Forms Competing Quadruplex and Protein Complexes in Functional Conditions

PubMed Central

Smith, Lindsay D.; Dickinson, Rachel L.; Lucas, Christian M.; Cousins, Alex; Malygin, Alexey A.; Weldon, Carika; Perrett, Andrew J.; Bottrill, Andrew R.; Searle, Mark S.; Burley, Glenn A.; Eperon, Ian C.

2014-01-01

Summary The use of oligonucleotides to activate the splicing of selected exons is limited by a poor understanding of the mechanisms affected. A targeted bifunctional oligonucleotide enhancer of splicing (TOES) anneals to SMN2 exon 7 and carries an exonic splicing enhancer (ESE) sequence. We show that it stimulates splicing specifically of intron 6 in the presence of repressing sequences in intron 7. Complementarity to the 5′ end of exon 7 increases U2AF65 binding, but the ESE sequence is required for efficient recruitment of U2 snRNP. The ESE forms at least three coexisting discrete states: a quadruplex, a complex containing only hnRNP F/H, and a complex enriched in the activator SRSF1. Neither hnRNP H nor quadruplex formation contributes to ESE activity. The results suggest that splicing limited by weak signals can be rescued by rapid exchange of TOES oligonucleotides in various complexes and raise the possibility that SR proteins associate transiently with ESEs. PMID:25263560

Group therapy of psoriasis. Duo formula group treatment (DFGT) as an example.

PubMed

Schulte, M B; Cormane, R H; van Dijk, E; Wuite, J

1985-01-01

Between 1978 and 1982 an experiment on group treatment for and by psoriasis sufferers was conducted, based on a pyramid of previous investigations since 1968. Each group was facilitated by a duo consisting of a fellow sufferer and a physician, both having trained together. The subjects practiced the procedure described, directed toward self-care and mutual aid facilitated and supported by the duo, in a series of ten 2-hour weekly sessions. A pretest/posttest control group design was used. Comparing the results of the quantitative analysis of the experimental groups with those of the control groups, the experimental groups showed significant change. The results of the qualitative analysis showed that decrease of anxiety correlated with mastering of the skills involved. The key element affecting outcome was the balance in cooperation within the duo, the expertise of the patient lying in his personal experience of the condition, and the expertise of the physician in his knowledge and skills. One of the method's main characteristics was the intrinsic complementarity of the duo partners.

The Potential Power of Bar-HRM Technology in Herbal Medicine Identification

PubMed Central

Sun, Wei; Li, Jing-jian; Xiong, Chao; Zhao, Bo; Chen, Shi-lin

2016-01-01

The substitution of low-cost or adulterated herbal products for high-priced herbs makes it important to be able to identify and trace herbal plant species and their processed products in the drug supply chain. PCR-based methods play an increasing role in monitoring the safety of herbal medicines by detecting adulteration. Recent studies have shown the potential of DNA barcoding combined with high resolution melting (Bar-HRM) analysis in herbal medicine identification. This method involves precisely monitoring the change in fluorescence caused by the release of an intercalating DNA dye from a DNA duplex as it is denatured by a gradual increase in temperature. Since the melting profile depends on the GC content, length, and strand complementarity of the amplification product, Bar-HRM analysis opens up the possibility of detecting single-base variants or species-specific differences in a short region of DNA. This review summarizes key factors affecting Bar-HRM analysis and describes how Bar-HRM is performed. We then discuss advances in Bar-HRM analysis of medicinal plant ingredients (herbal materia medica) as a contribution toward safe and effective herbal medicines. PMID:27066026

The Potential Power of Bar-HRM Technology in Herbal Medicine Identification.

PubMed

Sun, Wei; Li, Jing-Jian; Xiong, Chao; Zhao, Bo; Chen, Shi-Lin

2016-01-01

The substitution of low-cost or adulterated herbal products for high-priced herbs makes it important to be able to identify and trace herbal plant species and their processed products in the drug supply chain. PCR-based methods play an increasing role in monitoring the safety of herbal medicines by detecting adulteration. Recent studies have shown the potential of DNA barcoding combined with high resolution melting (Bar-HRM) analysis in herbal medicine identification. This method involves precisely monitoring the change in fluorescence caused by the release of an intercalating DNA dye from a DNA duplex as it is denatured by a gradual increase in temperature. Since the melting profile depends on the GC content, length, and strand complementarity of the amplification product, Bar-HRM analysis opens up the possibility of detecting single-base variants or species-specific differences in a short region of DNA. This review summarizes key factors affecting Bar-HRM analysis and describes how Bar-HRM is performed. We then discuss advances in Bar-HRM analysis of medicinal plant ingredients (herbal materia medica) as a contribution toward safe and effective herbal medicines.

Investigating the association between social interactions and personality states dynamics.

PubMed

Gundogdu, Didem; Finnerty, Ailbhe N; Staiano, Jacopo; Teso, Stefano; Passerini, Andrea; Pianesi, Fabio; Lepri, Bruno

2017-09-01

The recent personality psychology literature has coined the name of personality states to refer to states having the same behavioural, affective and cognitive content (described by adjectives) as the corresponding trait, but for a shorter duration. The variability in personality states may be the reaction to specific characteristics of situations. The aim of our study is to investigate whether specific situational factors, that is, different configurations of face-to-face interactions, are predictors of variability of personality states in a work environment. The obtained results provide evidence that within-person variability in personality is associated with variation in face-to-face interactions. Interestingly, the effects differ by type and level of the personality states: adaptation effects for Agreeableness and Emotional Stability, whereby the personality states of an individual trigger similar states in other people interacting with them and complementarity effects for Openness to Experience, whereby the personality states of an individual trigger opposite states in other people interacting with them. Overall, these findings encourage further research to characterize face-to-face and social interactions in terms of their relevance to personality states.

A fire-affected community: the case of the West Melton fire, December 2003

Treesearch

Laura Kelly; Pamela J. Jakes; E.R. Langer

2008-01-01

A study of a fire-affected community was conducted to gain an understanding of the social ramifications of a wildfire event and to analyse how one community responded to this type of disaster. The research focused on the West Melton community, located just west of Christchurch, in the Selwyn District. This is the first in a series of case studies planned by the Scion...

Characterizing the Bacterial Communities in Retail Stores in the United States

DTIC Science & Technology

2015-01-01

community or the factors that affect it. To our knowledge, only one study to date has investigated the indoor bacterial microbiome of retail stores...type of store affects the microbial community present, the impact of store type on the bacterial community was investigated by comparing the bacteria...genes analysis (Figure 2). Additionally, Leff and Fierer (2013) observed a high relative abundance of Enterobacteriaceae on fruits and vegetables but

Complementarity of Rotating Video and Underwater Visual Census for Assessing Species Richness, Frequency and Density of Reef Fish on Coral Reef Slopes

PubMed Central

Mallet, Delphine; Wantiez, Laurent; Lemouellic, Soazig; Vigliola, Laurent; Pelletier, Dominique

2014-01-01

Estimating diversity and abundance of fish species is fundamental for understanding community structure and dynamics of coral reefs. When designing a sampling protocol, one crucial step is the choice of the most suitable sampling technique which is a compromise between the questions addressed, the available means and the precision required. The objective of this study is to compare the ability to sample reef fish communities at the same locations using two techniques based on the same stationary point count method: one using Underwater Visual Census (UVC) and the other rotating video (STAVIRO). UVC and STAVIRO observations were carried out on the exact same 26 points on the reef slope of an intermediate reef and the associated inner barrier reefs. STAVIRO systems were always deployed 30 min to 1 hour after UVC and set exactly at the same place. Our study shows that; (i) fish community observations by UVC and STAVIRO differed significantly; (ii) species richness and density of large species were not significantly different between techniques; (iii) species richness and density of small species were higher for UVC; (iv) density of fished species was higher for STAVIRO and (v) only UVC detected significant differences in fish assemblage structure across reef type at the spatial scale studied. We recommend that the two techniques should be used in a complementary way to survey a large area within a short period of time. UVC may census reef fish within complex habitats or in very shallow areas such as reef flat whereas STAVIRO would enable carrying out a large number of stations focused on large and diver-averse species, particularly in the areas not covered by UVC due to time and depth constraints. This methodology would considerably increase the spatial coverage and replication level of fish monitoring surveys. PMID:24392126

Impacts of online and group perinatal education: a mixed methods study protocol for the optimization of perinatal health services.

PubMed

Roch, Geneviève; Borgès Da Silva, Roxane; de Montigny, Francine; Witteman, Holly O; Pierce, Tamarha; Semenic, Sonia; Poissant, Julie; Parent, André-Anne; White, Deena; Chaillet, Nils; Dubois, Carl-Ardy; Ouimet, Mathieu; Lapointe, Geneviève; Turcotte, Stéphane; Prud'homme, Alexandre; Painchaud Guérard, Geneviève; Gagnon, Marie-Pierre

2018-05-29

Prenatal education is a core component of perinatal care and services provided by health institutions. Whereas group prenatal education is the most common educational model, some health institutions have opted to implement online prenatal education to address accessibility issues as well as the evolving needs of future parents. Various studies have shown that prenatal education can be effective in acquisition of knowledge on labour and delivery, reducing psychological distress and maximising father's involvement. However, these results may depend on educational material, organization, format and content. Furthermore, the effectiveness of online prenatal education compared to group prenatal education remains unclear in the literature. This project aims to evaluate the impacts of group prenatal education and online prenatal education on health determinants and users' health status, as well as on networks of perinatal educational services maintained with community-based partners. This multipronged mixed methods study uses a collaborative research approach to integrate and mobilize knowledge throughout the process. It consists of: 1) a prospective cohort study with quantitative data collection and qualitative interviews with future and new parents; and 2) a multiple case study integrating documentary sources and interviews with stakeholders involved in the implementation of perinatal information service networks and collaborations with community partners. Perinatal health indicators and determinants will be compared between prenatal education groups (group prenatal education and online prenatal education) and standard care without these prenatal education services (control group). This study will provide knowledge about the impact of online prenatal education as a new technological service delivery model compared to traditional group prenatal education. Indicators related to the complementarity of these interventions and those available in community settings will refine our understanding of regional perinatal services networks. Results will assist decision-making regarding service organization and delivery models of prenatal education services. Version 1 (February 9 2018).

Catchment land use-dependent effects of barrage fishponds on the functioning of headwater streams.

PubMed

Four, Brian; Arce, Evelyne; Danger, Michaël; Gaillard, Juliette; Thomas, Marielle; Banas, Damien

2017-02-01

Extensive fish production systems in continental areas are often created by damming headwater streams. However, these lentic systems favour autochthonous organic matter production. As headwater stream functioning is essentially based on allochthonous organic matter (OM) supply, the presence of barrage fishponds on headwater streams might change the main food source for benthic communities. The goal of this study was thus to identify the effects of barrage fishponds on the functioning of headwater streams. To this end, we compared leaf litter breakdown (a key ecosystem function in headwater streams), their associated invertebrate communities and fungal biomass at sites upstream and downstream of five barrage fishponds in two dominant land use systems (three in forested catchments and two in agricultural catchments). We observed significant structural and functional differences between headwater stream ecosystems in agricultural catchments and those in forested catchments. Leaf litter decay was more rapid in forest streams, with a moderate, but not significant, increase in breakdown rate downstream from the barrage fishponds. In agricultural catchments, the trend was opposite with a 2-fold lower leaf litter breakdown rate at downstream sites compared to upstream sites. Breakdown rates observed at all sites were closely correlated with fungal biomass and shredder biomass. No effect of barrage fishponds were observed in this study concerning invertebrate community structure or functional feeding groups especially in agricultural landscapes. In forest streams, we observed a decrease in organic pollution (OP)-intolerant taxa at downstream sites that was correlated with an increase in OP-tolerant taxa. These results highlighted that the influence of barrage fishponds on headwater stream functioning is complex and land use dependent. It is therefore necessary to clearly understand the various mechanisms (competition for food resources, complementarities between autochthonous and allochthonous OM) that control ecosystem functioning in different contexts in order to optimize barrage fishpond management.

Community size and composition of ammonia oxidizers and denitrifiers in an alluvial intertidal wetland ecosystem

PubMed Central

Hu, Ziye; Meng, Han; Shi, Jin-Huan; Bu, Nai-Shun; Fang, Chang-Ming; Quan, Zhe-Xue

2014-01-01

Global nitrogen cycling is mainly mediated by the activity of microorganisms. Nitrogen cycle processes are mediated by functional groups of microorganisms that are affected by constantly changing environmental conditions and substrate availability. In this study, we investigated the temporal and spatial patterns of nitrifier and denitrifier communities in an intertidal wetland. Soil samples were collected over four distinct seasons from three locations with different vegetative cover. Multiple environmental factors and process rates were measured and analyzed together with the community size and composition profiles. We observed that the community size and composition of the nitrifiers and denitrifiers are affected significantly by seasonal factors, while vegetative cover affected the community composition. The seasonal impacts on the community size of ammonia oxidizing archaea (AOA) are much higher than that of ammonia oxidizing bacteria (AOB). The seasonal change was a more important indicator for AOA community composition patterns, while vegetation was more important for the AOB community patterns. The microbial process rates were correlated with both the community size and composition. PMID:25101072

Planning for complementarity : an examination of the role and opportunities of first-tier and second-tier cities along the high-speed rail network in California.

DOT National Transportation Integrated Search

2012-03-01

The coming of California High-Speed Rail (HSR) offers opportunities for positive urban transformations in both first-tier and second-tier cities. The research in this report explores the different but complementary roles that first-tier and second-ti...

Education Policy, Globalization, Commercialization: An Interview with Bob Lingard by David Hursh

ERIC Educational Resources Information Center

Hursh, David

2017-01-01

In this interview with David Hursh, Bob Lingard comments on his current and/or recently completed research projects in respect to new modes of global governance in schooling and the complementarity between international large scale assessments and national testing. He also looks at a project that, in conjunction with school leaders, teachers,…

Revisiting the Complementarity between Education and Training--The Role of Job Tasks and Firm Effects

ERIC Educational Resources Information Center

Görlitz, Katja; Tamm, Marcus

2016-01-01

This paper addresses the question to what extent the strong positive correlation between education and training can be attributed to differences in individual-, job- and firm-specific characteristics. The novelty of this paper is to analyze previously unconsidered characteristics, in particular, job tasks and firm-fixed effects. The results show…

Amino Acid Complementarity: A Biochemical Exemplar of Stoichiometry for General and Health Sciences Chemistry

ERIC Educational Resources Information Center

Vitz, Ed

2005-01-01

The standard introduction to stoichiometry and simple exemplars can motivate students to learn the stoichiometric studies and the condensation reaction that occurs between amino acids to form the peptide bond. This topic can be integrated into general chemistry courses as an alternative to inclusion of a separate biochemistry course that could be…

India's Information Technology Sector: What Contribution to Broader Economic Development? OECD Development Centre Working Paper, No. 207 (Formerly Technical Paper No. 207)

ERIC Educational Resources Information Center

Singh, Nirvikar

2003-01-01

What contribution can information technology (IT) make to India's overall economic development? This paper provides an analytical framework centred around the concepts of comparative advantage, complementarities, and innovation. There is strong evidence that India has a strong and sustainable comparative advantage in software development and…

Black Hole Interior in Quantum Gravity.

PubMed

Nomura, Yasunori; Sanches, Fabio; Weinberg, Sean J

2015-05-22

We discuss the interior of a black hole in quantum gravity, in which black holes form and evaporate unitarily. The interior spacetime appears in the sense of complementarity because of special features revealed by the microscopic degrees of freedom when viewed from a semiclassical standpoint. The relation between quantum mechanics and the equivalence principle is subtle, but they are still consistent.

Value Creation, Appropriation, and Product Design Strategies in Technology Ecosystems: Three Essays on the Role of Complementary Technologies

ERIC Educational Resources Information Center

Miller, Cameron Dee

2017-01-01

Firms are often embedded in a technology ecosystem comprised of complementary technologies that span multiple product markets. In this dissertation, I examine how complementarity between the firm's technologies influences its strategies to create and appropriate value in the ecosystem. I investigate this overarching question in two contexts:…

Perceived Affordances, Tensions, and Complementarities in the Physical and Digital Environments Frequented by Future Teachers

ERIC Educational Resources Information Center

Pruneau, Diane; Kerry, Jackie; Freiman, Viktor; Langis, Joanne; Bizid, Mohamed

2016-01-01

Is future teachers' contact with the physical environment significant enough for them to choose to educate their students about sustainability? These digital natives stand out from previous generations by their way of living. The research based on grounded theory was aimed at understanding future teachers' relationships with physical and…

Spatial complementarity of forests and farms: accounting for ecosystem services

Treesearch

Subhrendu K. Pattanayak; David T. Butry

2006-01-01

Our article considers the economic contributions of forest ecosystem services, using a case study from Flores, Indonesia, in which forest protection in upstream watersheds stabilize soil and hydrological flows in downstream farms. We focus on the demand for a weak complement to the ecosystem services--farm labor-- and account for spatial dependence due to economic...

Qualitative and Quantitative Approaches to the Study of Poverty: Taming the Tensions and Appreciating the Complementarities

ERIC Educational Resources Information Center

Balarabe Kura, Sulaiman Y.

2012-01-01

There is a germane relationship between qualitative and quantitative approaches to social science research. The relationship is empirically and theoretically demonstrated by poverty researchers. The study of poverty, as argued in this article, is a study of both numbers and contextualities. This article provides a general overview of qualitative…

Community Collaboration Using a Unique Gallery as a Literacy Resource

ERIC Educational Resources Information Center

Voelker, Anita N.

2008-01-01

According to van der Pluijm (2006), an ecological community occurs when interacting groups, living in the same area, are joined together by the set of connections. This definition implies a symbiotic relationship and the acknowledgment that what affects one member or part of the community also affects the others. When the interconnections are…

Teachers' Challenges, Strategies, and Support Needs in Schools Affected by Community Violence: A Qualitative Study

ERIC Educational Resources Information Center

Maring, Elisabeth F.; Koblinsky, Sally A.

2013-01-01

Background: Exposure to community violence compromises teacher effectiveness, student learning, and socioemotional well-being. This study examined the challenges, strategies, and support needs of teachers in urban schools affected by high levels of community violence. Methods: Twenty teachers from 3 urban middle schools with predominantly…

How Do Learning Communities Affect First-Year Latino Students?

ERIC Educational Resources Information Center

Huerta, Juan Carlos; Bray, Jennifer J.

2013-01-01

Do learning communities with pedagogies of active learning, collaborative learning, and integration of course material affect the learning, achievement, and persistence of first-year Latino university students? The data for this project was obtained from a survey of 1,330 first-year students in the First-Year Learning Community Program at Texas…

E-Model for Online Learning Communities.

PubMed

Rogo, Ellen J; Portillo, Karen M

2015-10-01

The purpose of this study was to explore the students' perspectives on the phenomenon of online learning communities while enrolled in a graduate dental hygiene program. A qualitative case study method was designed to investigate the learners' experiences with communities in an online environment. A cross-sectional purposive sampling method was used. Interviews were the data collection method. As the original data were being analyzed, the researchers noted a pattern evolved indicating the phenomenon developed in stages. The data were re-analyzed and validated by 2 member checks. The participants' experiences revealed an e-model consisting of 3 stages of formal learning community development as core courses in the curriculum were completed and 1 stage related to transmuting the community to an informal entity as students experienced the independent coursework in the program. The development of the formal learning communities followed 3 stages: Building a Foundation for the Learning Community, Building a Supportive Network within the Learning Community and Investing in the Community to Enhance Learning. The last stage, Transforming the Learning Community, signaled a transition to an informal network of learners. The e-model was represented by 3 key elements: metamorphosis of relationships, metamorphosis through the affective domain and metamorphosis through the cognitive domain, with the most influential element being the affective development. The e-model describes a 4 stage process through which learners experience a metamorphosis in their affective, relationship and cognitive development. Synergistic learning was possible based on the interaction between synergistic relationships and affective actions. Copyright © 2015 The American Dental Hygienists’ Association.

Perceived community participation in tsunami recovery efforts and the mental health of tsunami-affected mothers: findings from a study in rural Sri Lanka.

PubMed

Wickrama, K A S; Wickrama, T

2011-09-01

The 2004 tsunami seriously affected millions of families in several developing countries by destroying their livelihoods, houses and communities, subsequently damaging social and physical resources. Disaster studies have documented that both post-traumatic stress disorder (PTSD) and depression develop during the first six months following disaster exposure for the majority of those afflicted. and Using data from 325 tsunami-affected families living in southern Sri Lanka, the current study investigates whether community social resources such as residents' perceived community participation in tsunami recovery efforts reduce mental health risks (PTSD and depressive symptoms) of tsunami-affected mothers. The analysis is based on structural equation modelling. and The findings of structural equation modelling supports the main hypothesis that residents' perceived community participation directly and indirectly (through collective family functioning and mental health service use) reduces mental health risks (both PTSD and depressive symptoms) of tsunami-affected mothers after controlling for pre-tsunami family adversities. In addition, the results show that residents' perceived community participation buffers the influence of trauma exposure on PTSD symptom levels of mothers. The identification of specific social and family processes that relate to mental health can be useful for post-disaster interventions and recovery programmes.

Endangered light-footed clapper rail affects parasite community structure in coastal wetlands

USGS Publications Warehouse

Whitney, Kathleen L.; Hechinger, Ryan F.; Kuris, Armand M.; Lafferty, Kevin D.

2007-01-01

An extinction necessarily affects community members that have obligate relationships with the extinct species. Indirect or cascading effects can lead to even broader changes at the community or ecosystem level. However, it is not clear whether generalist parasites should be affected by the extinction of one of their hosts. We tested the prediction that loss of a host species could affect the structure of a generalist parasite community by investigating the role of endangered Light-footed Clapper Rails (Rallus longirostris levipes) in structuring trematode communities in four tidal wetlands in southern California, USA (Carpinteria Salt Marsh, Mugu Lagoon) and Mexico (Estero de Punta Banda, Bahia Falsa–San Quintín). We used larval trematode parasites in first intermediate host snails (Cerithidea californica) as windows into the adult trematodes that parasitize Clapper Rails. Within and among wetlands, we found positive associations between Clapper Rails and four trematode species, particularly in the vegetated marsh habitat where Clapper Rails typically occur. This suggests that further loss of Clapper Rails is likely to affect the abundance of several competitively dominant trematode species in wetlands with California horn snails, with possible indirect effects on the trematode community and changes in the impacts of these parasites on fishes and invertebrates.

Grain-dependent responses of mammalian diversity to land use and the implications for conservation set-aside.

PubMed

Wearn, Oliver R; Carbone, Chris; Rowcliffe, J Marcus; Bernard, Henry; Ewers, Robert M

2016-07-01

Diversity responses to land-use change are poorly understood at local scales, hindering our ability to make forecasts and management recommendations at scales which are of practical relevance. A key barrier in this has been the underappreciation of grain-dependent diversity responses and the role that β-diversity (variation in community composition across space) plays in this. Decisions about the most effective spatial arrangement of conservation set-aside, for example high conservation value areas, have also neglected β-diversity, despite its role in determining the complementarity of sites. We examined local-scale mammalian species richness and β-diversity across old-growth forest, logged forest, and oil palm plantations in Borneo, using intensive camera- and live-trapping. For the first time, we were able to investigate diversity responses, as well as β-diversity, at multiple spatial grains, and across the whole terrestrial mammal community (large and small mammals); β-diversity was quantified by comparing observed β-diversity with that obtained under a null model, in order to control for sampling effects, and we refer to this as the β-diversity signal. Community responses to land use were grain dependent, with large mammals showing reduced richness in logged forest compared to old-growth forest at the grain of individual sampling points, but no change at the overall land-use level. Responses varied with species group, however, with small mammals increasing in richness at all grains in logged forest compared to old-growth forest. Both species groups were significantly depauperate in oil palm. Large mammal communities in old-growth forest became more heterogeneous at coarser spatial grains and small mammal communities became more homogeneous, while this pattern was reversed in logged forest. Both groups, however, showed a significant β-diversity signal at the finest grain in logged forest, likely due to logging-induced environmental heterogeneity. The β-diversity signal in oil palm was weak, but heterogeneity at the coarsest spatial grain was still evident, likely due to variation in landscape forest cover. Our findings suggest that the most effective spatial arrangement of set-aside will involve trade-offs between conserving large and small mammals. Greater consideration in the conservation and management of tropical landscapes needs to be given to β-diversity at a range of spatial grains. © 2016 by the Ecological Society of America.

Relationship between the Decomposition Process of Coarse Woody Debris and Fungal Community Structure as Detected by High-Throughput Sequencing in a Deciduous Broad-Leaved Forest in Japan

PubMed Central

Yamashita, Satoshi; Masuya, Hayato; Abe, Shin; Masaki, Takashi; Okabe, Kimiko

2015-01-01

We examined the relationship between the community structure of wood-decaying fungi, detected by high-throughput sequencing, and the decomposition rate using 13 years of data from a forest dynamics plot. For molecular analysis and wood density measurements, drill dust samples were collected from logs and stumps of Fagus and Quercus in the plot. Regression using a negative exponential model between wood density and time since death revealed that the decomposition rate of Fagus was greater than that of Quercus. The residual between the expected value obtained from the regression curve and the observed wood density was used as a decomposition rate index. Principal component analysis showed that the fungal community compositions of both Fagus and Quercus changed with time since death. Principal component analysis axis scores were used as an index of fungal community composition. A structural equation model for each wood genus was used to assess the effect of fungal community structure traits on the decomposition rate and how the fungal community structure was determined by the traits of coarse woody debris. Results of the structural equation model suggested that the decomposition rate of Fagus was affected by two fungal community composition components: one that was affected by time since death and another that was not affected by the traits of coarse woody debris. In contrast, the decomposition rate of Quercus was not affected by coarse woody debris traits or fungal community structure. These findings suggest that, in the case of Fagus coarse woody debris, the fungal community structure is related to the decomposition process of its host substrate. Because fungal community structure is affected partly by the decay stage and wood density of its substrate, these factors influence each other. Further research on interactive effects is needed to improve our understanding of the relationship between fungal community structure and the woody debris decomposition process. PMID:26110605

Effects of the thermal discharge from an offshore power plant on plankton and macrobenthic communities in subtropical China.

PubMed

Lin, Jie; Zou, Xinqing; Huang, Faming

2018-06-01

The ecological impact of thermal discharge has become an important issue in the field of marine and environmental protection. We focused on the effects of thermal discharge on seawater temperature and biological communities based on data from before (2006) and after (2013-2014) the construction of a power plant. The thermal discharge induced stratification, which resulted in changes in the vertical hydrodynamic conditions. Stratification combined with elevated temperatures significantly affected the phytoplankton abundance and community structure. Elevated seawater temperatures decreased the chlorophyll-a concentrations by 34% and 63%, at the surface and bottom, respectively. The elevated seawater temperature at the bottom might not be high enough to significantly affect the macrobenthos, but significantly affected the phytoplankton and zooplankton communities. Because these communities serve as food for the macrobenthic community, their changes resulted in growth of the macrobenthos. Furthermore, this effect induced macrobenthic community succession, resulting in decreased species diversity and increased dominance. Copyright © 2018 Elsevier Ltd. All rights reserved.

Identification of Major Rhizobacterial Taxa Affected by a Glyphosate-Tolerant Soybean Line via Shotgun Metagenomic Approach

PubMed Central

Hua, Xiao-Mei; Liang, Li; Wen, Zhong-Ling; Du, Mei-Hang; Meng, Fan-Fan; Pang, Yan-Jun; Tang, Cheng-Yi

2018-01-01

The worldwide commercial cultivation of transgenic crops, including glyphosate-tolerant (GT) soybeans, has increased widely during the past 20 years. However, it is accompanied with a growing concern about potential effects of transgenic crops on the soil microbial communities, especially on rhizosphere bacterial communities. Our previous study found that the GT soybean line NZL06-698 (N698) significantly affected rhizosphere bacteria, including some unidentified taxa, through 16S rRNA gene (16S rDNA) V4 region amplicon deep sequencing via Illumina MiSeq. In this study, we performed 16S rDNA V5–V7 region amplicon deep sequencing via Illumina MiSeq and shotgun metagenomic approaches to identify those major taxa. Results of these processes revealed that the species richness and evenness increased in the rhizosphere bacterial communities of N698, the beta diversity of the rhizosphere bacterial communities of N698 was affected, and that certain dominant bacterial phyla and genera were related to N698 compared with its control cultivar Mengdou12. Consistent with our previous findings, this study showed that N698 affects the rhizosphere bacterial communities. In specific, N698 negatively affects Rahnella, Janthinobacterium, Stenotrophomonas, Sphingomonas and Luteibacter while positively affecting Arthrobacter, Bradyrhizobium, Ramlibacter and Nitrospira. PMID:29659545

Simulated nitrogen deposition affects community structure of arbuscular mycorrhizal fungi in northern hardwood forests

Treesearch

Linda T.A. Van Diepen; Erik Lilleskov; Kurt S. Pregitzer

2011-01-01

Our previous investigation found elevated nitrogen deposition caused declines in abundance of arbuscular mycorrhizal fungi (AMF) associated with forest trees, but little is known about how nitrogen affects the AMF community composition and structure within forest ecosystems. We hypothesized that N deposition would lead to significant changes in the AMF community...

Fungal and Bacterial Communities in Indoor Dust Follow Different Environmental Determinants.

PubMed

Weikl, Fabian; Tischer, Christina; Probst, Alexander J; Heinrich, Joachim; Markevych, Iana; Jochner, Susanne; Pritsch, Karin

2016-01-01

People spend most of their time inside buildings and the indoor microbiome is a major part of our everyday environment. It affects humans' wellbeing and therefore its composition is important for use in inferring human health impacts. It is still not well understood how environmental conditions affect indoor microbial communities. Existing studies have mostly focussed on the local (e.g., building units) or continental scale and rarely on the regional scale, e.g. a specific metropolitan area. Therefore, we wanted to identify key environmental determinants for the house dust microbiome from an existing collection of spatially (area of Munich, Germany) and temporally (301 days) distributed samples and to determine changes in the community as a function of time. To that end, dust samples that had been collected once from the living room floors of 286 individual households, were profiled for fungal and bacterial community variation and diversity using microbial fingerprinting techniques. The profiles were tested for their association with occupant behaviour, building characteristics, outdoor pollution, vegetation, and urbanization. Our results showed that more environmental and particularly outdoor factors (vegetation, urbanization, airborne particulate matter) affected the community composition of indoor fungi than of bacteria. The passage of time affected fungi and, surprisingly, also strongly affected bacteria. We inferred that fungal communities in indoor dust changed semi-annually, whereas bacterial communities paralleled outdoor plant phenological periods. These differences in temporal dynamics cannot be fully explained and should be further investigated in future studies on indoor microbiomes.

Fungal and Bacterial Communities in Indoor Dust Follow Different Environmental Determinants

PubMed Central

Weikl, Fabian; Tischer, Christina; Probst, Alexander J.; Heinrich, Joachim; Markevych, Iana; Jochner, Susanne; Pritsch, Karin

2016-01-01

People spend most of their time inside buildings and the indoor microbiome is a major part of our everyday environment. It affects humans’ wellbeing and therefore its composition is important for use in inferring human health impacts. It is still not well understood how environmental conditions affect indoor microbial communities. Existing studies have mostly focussed on the local (e.g., building units) or continental scale and rarely on the regional scale, e.g. a specific metropolitan area. Therefore, we wanted to identify key environmental determinants for the house dust microbiome from an existing collection of spatially (area of Munich, Germany) and temporally (301 days) distributed samples and to determine changes in the community as a function of time. To that end, dust samples that had been collected once from the living room floors of 286 individual households, were profiled for fungal and bacterial community variation and diversity using microbial fingerprinting techniques. The profiles were tested for their association with occupant behaviour, building characteristics, outdoor pollution, vegetation, and urbanization. Our results showed that more environmental and particularly outdoor factors (vegetation, urbanization, airborne particulate matter) affected the community composition of indoor fungi than of bacteria. The passage of time affected fungi and, surprisingly, also strongly affected bacteria. We inferred that fungal communities in indoor dust changed semi-annually, whereas bacterial communities paralleled outdoor plant phenological periods. These differences in temporal dynamics cannot be fully explained and should be further investigated in future studies on indoor microbiomes. PMID:27100967

Repeated disturbances affect functional but not compositional resistance and resilience in an aquatic bacterioplankton community.

PubMed

Sjöstedt, Johanna; Langenheder, Silke; Kritzberg, Emma; Karlsson, Christofer M G; Lindström, Eva S

2018-05-07

Disturbances are believed to be one of the main factors influencing variations in community diversity and functioning. Here we investigated if exposure to a pH press disturbance affected the composition and functional performance of a bacterial community and its resistance, recovery and resilience to a second press disturbance (salt addition). Lake bacterial assemblages were initially exposed to reduced pH in six mesocosms whereas another six mesocosms were kept as reference. Seven days after the pH disturbance, three tanks from each treatment were exposed to a salt disturbance. Both bacterial production and enzyme activity were negatively affected by the salt treatment, regardless if the communities had been subject to a previous disturbance or not. However, cell-specific enzyme activity had a higher resistance in communities pre-exposed to the pH disturbance compared to the reference treatment. In contrast, for cell-specific bacterial production resistance was not affected, but recovery was faster in the communities that had previously been exposed to the pH disturbance. Over time, bacterial community composition diverged among treatments, in response to both pH and salinity. The difference in functional recovery, resilience and resistance may depend on differences in community composition caused by the pH disturbance, niche breadth or acquired stress resistance. This article is protected by copyright. All rights reserved. © 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.

Cooperative Agreements to Support Communities Affected by the BP Oil Spill

EPA Pesticide Factsheets

The environmental justice cooperative agreements are designed to support communities in Alabama, Florida, Louisiana, Mississippi, and Texas that are directly affected by the Deepwater Horizon oil spill in the Gulf of Mexico.

Analysis of the Underlying Cognitive Activity in the Resolution of a Task on Derivability of the Absolute-Value Function: Two Theoretical Perspectives

ERIC Educational Resources Information Center

Pino-Fan, Luis R.; Guzmán, Ismenia; Font, Vicenç; Duval, Raymond

2017-01-01

This paper presents a study of networking of theories between the theory of registers of semiotic representation (TRSR) and the onto-semiotic approach of mathematical cognition and instruction (OSA). The results obtained show complementarities between these two theoretical perspectives, which might allow more detailed analysis of the students'…

The Role of Teaching Presence and Student Participation in Spanish Blended Courses

ERIC Educational Resources Information Center

Rubio, Fernando; Thomas, Jonathan M.; Li, Qin

2018-01-01

This chapter describes a study of a blended language course that combines face-to-face (F2F) instructional time with an online component. The purpose of the study is to understand how teachers and students exploit the complementarity of the two delivery formats to improve the learning experience. The study first examines how the presence of an…

Wave-Particle Dualism in Action

NASA Astrophysics Data System (ADS)

Schleich, Wolfgang P.

The wave-particle dualism, that is the wave nature of particles and the particle nature of light together with the uncertainty relation of Werner Heisenberg and the principle of complementarity formulated by Niels Bohr represent pillars of quantum theory. We provide an introduction into these fascinating yet strange aspects of the microscopic world and summarize key experiments confirming these concepts so alien to our daily life.

More than Just Not Being Alone: The Number, Nature, and Complementarity of Meal-Time Social Interactions Influence Food Intake in Hospitalized Elderly Patients

ERIC Educational Resources Information Center

Paquet, Catherine; St.-Arnaud-McKenzie, Danielle; Ma, Zhenfeng; Kergoat, Marie-Jeanne; Ferland, Guylaine; Dube, Laurette

2008-01-01

Purpose: This study evaluated the social facilitation of elderly patients' food intake beyond the presence of mealtime companions by assessing various relationships. The study examined the relationships between patients' intake and (a) the number of interpersonal exchanges with mealtime fellows, (b) the nature of behaviors expressed by the…

Higher order sensitivity of solutions to convex programming problems without strict complementarity

NASA Technical Reports Server (NTRS)

Malanowski, Kazimierz

1988-01-01

Consideration is given to a family of convex programming problems which depend on a vector parameter. It is shown that the solutions of the problems and the associated Lagrange multipliers are arbitrarily many times directionally differentiable functions of the parameter, provided that the data of the problems are sufficiently regular. The characterizations of the respective derivatives are given.

A Model of Process-Based Automation: Cost and Quality Implications in the Medication Management Process

ERIC Educational Resources Information Center

Spaulding, Trent Joseph

2011-01-01

The objective of this research is to understand how a set of systems, as defined by the business process, creates value. The three studies contained in this work develop the model of process-based automation. The model states that complementarities among systems are specified by handoffs in the business process. The model also provides theory to…

Firewalls from double purity

NASA Astrophysics Data System (ADS)

Bousso, Raphael

2013-10-01

The firewall paradox is often presented as arising from double entanglement, but I argue that more generally the paradox is double purity. Near-horizon modes are purified by the interior, in the infalling vacuum. Hence, they cannot also be pure alone, or in combination with any third system, as demanded by unitarity. This conflict arises independently of the Page time, for entangled and for pure states. It implies that identifications of Hilbert spaces cannot resolve the paradox. Traditional complementarity requires the unitary identification of infalling matter with a scrambled subsystem of the Hawking radiation. Extending this map to the infalling vacuum overdetermines the out-state. More general complementarity maps (“A=RB,” “ER=EPR”) necessarily fail when the near-horizon zone is pure. I argue that pure-zone states span the microcanonical ensemble, and that this suffices to make the horizon a special place. I advocate that the ability to detect the horizon locally, rather than the degree or probability of violence, is what makes firewalls problematic. Conversely, if the production of matter at the horizon can be dynamically understood and shown to be consistent, then firewalls do not constitute a violation of the equivalence principle.

Hertz's special relativity and physical reality.

NASA Astrophysics Data System (ADS)

Mocanu, C. I.

Maxwell-Hertz electrodynamics (MHE), valid for nonuniform motions as they occur in physical reality and which holds for the noninertial reference frame of our laboratory at small velocities only, is extended to relativistic velocities. The new theory, called Hertz's relativistic electrodynamics (HRE), is completely independent and built-up in a completely different way than Einstein's special relativity (ESR). HRE, a coordinate-free formulation, does not need postulates, but confirms the constancy principle of the speed of light in a vacuum. All experiments of first and second order in v2/c2 are correctly interpreted. To this theory a Hertzian kinematics and dynamics are associated. HRE with its corresponding mechanics form Hertz's special relativity (HSR) as a theory complementary to ESR. According to the principle of complementarity and neglecting gravitational effects, extended special relativity (ExSR) is a double-faced theory which becomes either ESR when the motion is inertial or HSR when the motion is noninertial. The complementarity of both theories assumes that the two descriptions cannot be employed for the same motion, being mutually exclusive. Consequently, to every statement of ExSR, a complementary statement of the other ExSR corresponds. The completeness of ESR with HSR ensures an extended view over relativity in our physical world.

The Kantian framework of complementarity

NASA Astrophysics Data System (ADS)

Cuffaro, Michael

A growing number of commentators have, in recent years, noted the important affinities in the views of Immanuel Kant and Niels Bohr. While these commentators are correct, the picture they present of the connections between Bohr and Kant is painted in broad strokes; it is open to the criticism that these affinities are merely superficial. In this essay, I provide a closer, structural, analysis of both Bohr's and Kant's views that makes these connections more explicit. In particular, I demonstrate the similarities between Bohr's argument, on the one hand, that neither the wave nor the particle description of atomic phenomena pick out an object in the ordinary sense of the word, and Kant's requirement, on the other hand, that both 'mathematical' (having to do with magnitude) and 'dynamical' (having to do with an object's interaction with other objects) principles must be applicable to appearances in order for us to determine them as objects of experience. I argue that Bohr's 'complementarity interpretation' of quantum mechanics, which views atomic objects as idealizations, and which licenses the repeal of the principle of causality for the domain of atomic physics, is perfectly compatible with, and indeed follows naturally from a broadly Kantian epistemological framework.

Economic Assimilation and Skill Acquisition: Evidence From the Occupational Sorting of Childhood Immigrants.

PubMed

Bacolod, Marigee; Rangel, Marcos A

2017-04-01

We study the economic assimilation of childhood immigrants to the United States. The linguistic distance between English and the predominant language in one's country of birth interacted with age at arrival is shown to be closely connected to occupational sorting in adulthood. By applying big-data techniques to occupations' detailed skill requirements, we provide evidence that childhood immigrants from English-distant countries who arrived after the primary school years reveal comparative advantages in tasks distinct from those for which (close to) Anglophone immigrants are better suited. Meanwhile, those who arrive at younger ages specialize in a bundle of skills very similar to that supplied by observationally equivalent workers. These patterns emerge even after we net out the effects of formal education. Such findings are compatible with the existence of different degrees of complementarity between relative English-learning potential at arrival and the acquisition of multiple capabilities demanded in the U.S. labor market (math/logic, socioemotional, physical, and communication skills). Consistent with the investment-complementarity argument, we show that linguistic distance and age at arrival also play a significant role on the choice of college major within this population.

Omics Data Complementarity Underlines Functional Cross-Communication in Yeast.

PubMed

Malod-Dognin, Noël; Pržulj, Nataša

2017-06-10

Mapping the complete functional layout of a cell and understanding the cross-talk between different processes are fundamental challenges. They elude us because of the incompleteness and noisiness of molecular data and because of the computational intractability of finding the exact answer. We perform a simple integration of three types of baker's yeast omics data to elucidate the functional organization and lines of cross-functional communication. We examine protein-protein interaction (PPI), co-expression (COEX) and genetic interaction (GI) data, and explore their relationship with the gold standard of functional organization, the Gene Ontology (GO). We utilize a simple framework that identifies functional cross-communication lines in each of the three data types, in GO, and collectively in the integrated model of the three omics data types; we present each of them in our new Functional Organization Map (FOM) model. We compare the FOMs of the three omics datasets with the FOM of GO and find that GI is in best agreement with GO, followed COEX and PPI. We integrate the three FOMs into a unified FOM and find that it is in better agreement with the FOM of GO than those of any omics dataset alone, demonstrating functional complementarity of different omics data.

Genome-Wide Spectra of Transcription Insertions and Deletions Reveal That Slippage Depends on RNA:DNA Hybrid Complementarity

PubMed Central

Traverse, Charles C.

2017-01-01

ABSTRACT Advances in sequencing technologies have enabled direct quantification of genome-wide errors that occur during RNA transcription. These errors occur at rates that are orders of magnitude higher than rates during DNA replication, but due to technical difficulties such measurements have been limited to single-base substitutions and have not yet quantified the scope of transcription insertions and deletions. Previous reporter gene assay findings suggested that transcription indels are produced exclusively by elongation complex slippage at homopolymeric runs, so we enumerated indels across the protein-coding transcriptomes of Escherichia coli and Buchnera aphidicola, which differ widely in their genomic base compositions and incidence of repeat regions. As anticipated from prior assays, transcription insertions prevailed in homopolymeric runs of A and T; however, transcription deletions arose in much more complex sequences and were rarely associated with homopolymeric runs. By reconstructing the relocated positions of the elongation complex as inferred from the sequences inserted or deleted during transcription, we show that continuation of transcription after slippage hinges on the degree of nucleotide complementarity within the RNA:DNA hybrid at the new DNA template location. PMID:28851848

The promise of complementarity: Using the methods of foresight for health workforce planning.

PubMed

Rees, Gareth H; Crampton, Peter; Gauld, Robin; MacDonell, Stephen

2018-05-01

Health workforce planning aims to meet a health system's needs with a sustainable and fit-for-purpose workforce, although its efficacy is reduced in conditions of uncertainty. This PhD breakthrough article offers foresight as a means of addressing this uncertainty and models its complementarity in the context of the health workforce planning problem. The article summarises the findings of a two-case multi-phase mixed method study that incorporates actor analysis, scenario development and policy Delphi. This reveals a few dominant actors of considerable influence who are in conflict over a few critical workforce issues. Using these to augment normative scenarios, developed from existing clinically developed model of care visions, a number of exploratory alternative descriptions of future workforce situations are produced for each case. Their analysis reveals that these scenarios are a reasonable facsimile of plausible futures, though some are favoured over others. Policy directions to support these favoured aspects can also be identified. This novel approach offers workforce planners and policy makers some guidance on the use of complimentary data, methods to overcome the limitations of conventional workforce forecasting and a framework for exploring the complexities and ambiguities of a health workforce's evolution.

Leader-team complementarity: Exploring the interactive effects of leader personality traits and team power distance values on team processes and performance.

PubMed

Hu, Jia; Judge, Timothy A

2017-06-01

Integrating the leader trait perspective with dominance complementarity theory, we propose team power distance as an important boundary condition for the indirect impact of leader extraversion, agreeableness, and conscientiousness on team performance through a team's potency beliefs and through relational identification with the leader. Using time-lagged, 3-source data from 71 teams, we found that leader extraversion had a positive indirect impact on team in-role and extrarole performance through relational identification, but only for high power distance teams; leader conscientiousness had a positive influence on team in-role performance through team potency, but only for high power distance teams; and leader agreeableness had a positive effect on team in-role and extrarole performance via relational identification and on team in-role performance via team potency, but only for low power distance teams. The findings address prior inconsistencies regarding the relationships between leader traits and team effectiveness, identify an important boundary condition and key team processes that bridge the links, and provide a deeper understanding of the role of leader traits in teams. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

In vivo encapsulation of nucleic acids using an engineered nonviral protein capsid.

PubMed

Lilavivat, Seth; Sardar, Debosmita; Jana, Subrata; Thomas, Geoffrey C; Woycechowsky, Kenneth J

2012-08-15

In Nature, protein capsids function as molecular containers for a wide variety of molecular cargoes. Such containers have great potential for applications in nanotechnology, which often require encapsulation of non-native guest molecules. Charge complementarity represents a potentially powerful strategy for engineering novel encapsulation systems. In an effort to explore the generality of this approach, we engineered a nonviral, 60-subunit capsid, lumazine synthase from Aquifex aeolicus (AaLS), to act as a container for nucleic acid. Four mutations were introduced per subunit to increase the positive charge at the inner surface of the capsid. Characterization of the mutant (AaLS-pos) revealed that the positive charges lead to the uptake of cellular RNA during production and assembly of the capsid in vivo. Surprisingly, AaLS-pos capsids were found to be enriched with RNA molecules approximately 200-350 bases in length, suggesting that this simple charge complementarity approach to RNA encapsulation leads to both high affinity and a degree of selectivity. The ability to control loading of RNA by tuning the charge at the inner surface of a protein capsid could illuminate aspects of genome recognition by viruses and pave the way for the development of improved RNA delivery systems.

Molecular origins of osmotic second virial coefficients of proteins.

PubMed Central

Neal, B L; Asthagiri, D; Lenhoff, A M

1998-01-01

The thermodynamic properties of protein solutions are determined by the molecular interactions involving both solvent and solute molecules. A quantitative understanding of the relationship would facilitate more systematic procedures for manipulating the properties in a process environment. In this work the molecular basis for the osmotic second virial coefficient, B22, is studied; osmotic effects are critical in membrane transport, and the value of B22 has also been shown to correlate with protein crystallization behavior. The calculations here account for steric, electrostatic, and short-range interactions, with the structural and functional anisotropy of the protein molecules explicitly accounted for. The orientational dependence of the protein interactions is seen to have a pronounced effect on the calculations; in particular, the relatively few protein-protein configurations in which the apposing surfaces display geometric complementarity contribute disproportionately strongly to B22. The importance of electrostatic interactions is also amplified in these high-complementarity configurations. The significance of molecular recognition in determining B22 can explain the correlation with crystallization behavior, and it suggests that alteration of local molecular geometry can help in manipulating protein solution behavior. The results also have implications for the role of protein interactions in biological self-organization. PMID:9788942

Generation of a chickenized catalytic anti-nucleic acid antibody by complementarity-determining region grafting.

PubMed

Roh, Jooho; Byun, Sung June; Seo, Youngsil; KIm, Minjae; Lee, Jae-Ho; Kim, Songmi; Lee, Yuno; Lee, Keun Woo; Kim, Jin-Kyoo; Kwon, Myung-Hee

2015-02-01

In contrast to a number of studies on the humanization of non-human antibodies, the reshaping of a non-human antibody into a chicken antibody has never been attempted. Therefore, nothing is known about the animal species-dependent compatibility of the framework regions (FRs) that sustain the appropriate conformation of the complementarity-determining regions (CDRs). In this study, we attempted the reshaping of the variable domains of the mouse catalytic anti-nucleic acid antibody 3D8 (m3D8) into the FRs of a chicken antibody (“chickenization”) by CDR grafting, which is a common method for the humanization of antibodies. CDRs of the acceptor chicken antibody that showed a high homology to the FRs of m3D8 were replaced with those of m3D8, resulting in the chickenized antibody (ck3D8). ck3D8 retained the biochemical properties (DNA binding, DNA hydrolysis, and cellular internalizing activities) and three-dimensional structure of m3D8 and showed reduced immunogenicity in chickens. Our study demonstrates that CDR grafting can be applied to the chickenization of a mouse antibody, probably due to the interspecies compatibility of the FRs.

A Physicist's Quest in Biology: Max Delbrück and "Complementarity".

PubMed

Strauss, Bernard S

2017-06-01

Max Delbrück was trained as a physicist but made his major contribution in biology and ultimately shared a Nobel Prize in Physiology or Medicine. He was the acknowledged leader of the founders of molecular biology, yet he failed to achieve his key scientific goals. His ultimate scientific aim was to find evidence for physical laws unique to biology: so-called "complementarity." He never did. The specific problem he initially wanted to solve was the nature of biological replication but the discovery of the mechanism of replication was made by others, in large part because of his disdain for the details of biochemistry. His later career was spent investigating the effect of light on the fungus Phycomyces , a topic that turned out to be of limited general interest. He was known both for his informality but also for his legendary displays of devastating criticism. His life and that of some of his closest colleagues was acted out against a background of a world in conflict. This essay describes the man and his career and searches for an explanation of his profound influence. Copyright © 2017 by the Genetics Society of America.

Directed evolution of human T cell receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without increasing apparent cross-reactivity

PubMed Central

Dunn, Steven M.; Rizkallah, Pierre J.; Baston, Emma; Mahon, Tara; Cameron, Brian; Moysey, Ruth; Gao, Feng; Sami, Malkit; Boulter, Jonathan; Li, Yi; Jakobsen, Bent K.

2006-01-01

The mammalian α/β T cell receptor (TCR) repertoire plays a pivotal role in adaptive immunity by recognizing short, processed, peptide antigens bound in the context of a highly diverse family of cell-surface major histocompatibility complexes (pMHCs). Despite the extensive TCR–MHC interaction surface, peptide-independent cross-reactivity of native TCRs is generally avoided through cell-mediated selection of molecules with low inherent affinity for MHC. Here we show that, contrary to expectations, the germ line-encoded complementarity determining regions (CDRs) of human TCRs, namely the CDR2s, which appear to contact only the MHC surface and not the bound peptide, can be engineered to yield soluble low nanomolar affinity ligands that retain a surprisingly high degree of specificity for the cognate pMHC target. Structural investigation of one such CDR2 mutant implicates shape complementarity of the mutant CDR2 contact interfaces as being a key determinant of the increased affinity. Our results suggest that manipulation of germ line CDR2 loops may provide a useful route to the production of high-affinity TCRs with therapeutic and diagnostic potential. PMID:16600963

Ligand Binding Site Detection by Local Structure Alignment and Its Performance Complementarity

PubMed Central

Lee, Hui Sun; Im, Wonpil

2013-01-01

Accurate determination of potential ligand binding sites (BS) is a key step for protein function characterization and structure-based drug design. Despite promising results of template-based BS prediction methods using global structure alignment (GSA), there is a room to improve the performance by properly incorporating local structure alignment (LSA) because BS are local structures and often similar for proteins with dissimilar global folds. We present a template-based ligand BS prediction method using G-LoSA, our LSA tool. A large benchmark set validation shows that G-LoSA predicts drug-like ligands’ positions in single-chain protein targets more precisely than TM-align, a GSA-based method, while the overall success rate of TM-align is better. G-LoSA is particularly efficient for accurate detection of local structures conserved across proteins with diverse global topologies. Recognizing the performance complementarity of G-LoSA to TM-align and a non-template geometry-based method, fpocket, a robust consensus scoring method, CMCS-BSP (Complementary Methods and Consensus Scoring for ligand Binding Site Prediction), is developed and shows improvement on prediction accuracy. The G-LoSA source code is freely available at http://im.bioinformatics.ku.edu/GLoSA. PMID:23957286

Dynamics of the mental health workforce: investigating the composition of physicians and other health providers.

PubMed

Stefos, Theodore; Burgess, James F; Cohen, Jeffrey P; Lehner, Laura; Moran, Eileen

2012-12-01

We evaluate how changes to mental health workforce levels, composition, and degree of labor substitution, may impact typical practice output. Using a generalized Leontief production function and data from 134 U.S. Department of Veterans Affairs (VA) mental health practices, we estimate the q-complementarity/q-substitutability of mental health workers. We look at the entire spectrum of mental health services rather than just outpatient or physician office services. We also examine more labor types, including residents, than previous studies. The marginal patient care output contribution is estimated for each labor type as well as the degree to which physicians and other mental health workers may be substitutes or complements. Results indicate that numerous channels exist through which input substitution can improve productivity. Seven of eight labor and capital inputs have positive estimated marginal products. Most factor inputs exhibit diminishing marginal productivity. Of 28 unique labor-capital pairs, 17 are q-complements and 11 are q-substitutes. Complementarity among several labor types provides evidence of a team approach to mental health service provision. Our approach may serve to better inform healthcare providers regarding more productive mental health workforce composition both in and outside of VA.

Complementarity among natural enemies enhances pest suppression.

PubMed

Dainese, Matteo; Schneider, Gudrun; Krauss, Jochen; Steffan-Dewenter, Ingolf

2017-08-15

Natural enemies have been shown to be effective agents for controlling insect pests in crops. However, it remains unclear how different natural enemy guilds contribute to the regulation of pests and how this might be modulated by landscape context. In a field exclusion experiment in oilseed rape (OSR), we found that parasitoids and ground-dwelling predators acted in a complementary way to suppress pollen beetles, suggesting that pest control by multiple enemies attacking a pest during different periods of its occurrence in the field improves biological control efficacy. The density of pollen beetle significantly decreased with an increased proportion of non-crop habitats in the landscape. Parasitism had a strong effect on pollen beetle numbers in landscapes with a low or intermediate proportion of non-crop habitats, but not in complex landscapes. Our results underline the importance of different natural enemy guilds to pest regulation in crops, and demonstrate how biological control can be strengthened by complementarity among natural enemies. The optimization of natural pest control by adoption of specific management practices at local and landscape scales, such as establishing non-crop areas, low-impact tillage, and temporal crop rotation, could significantly reduce dependence on pesticides and foster yield stability through ecological intensification in agriculture.

Improving community mental health services for people affected by political violence in Ayacucho, Perú.

PubMed

Rivera-Holguin, Miryam; Velazquez, Tesania; Custodio, Elba; Corveleyn, Jozef

2018-01-01

This study describes a model to intervene in communities affected by the political violence impacting the Ayacucho region of Peru since 1980s. Many community members still experience psychosocial consequences to this day due primarily to grief. Thirty-eight professionals from different sectors in the area received specialized training and implemented five community projects that were accompanied and monitored in the field by a team of community psychologists. This article is grounded on the principles of participation, building community capacity, and community strengthening. We present the analysis of five community action plans implemented over a period of 14 months. The results show a process of internal strengthening of community services and the identification of new social and community resources among the people involved in the action plans. The implications of capacity building for improving community mental health are discussed.

Evaluation of a Coordinated School-Based Obesity Prevention Program in a Hispanic Community: Choosing Healthy and Active Lifestyles for Kids/healthy Schools Healthy Families

ERIC Educational Resources Information Center

Berger-Jenkins, Evelyn; Rausch, John; Okah, Ebiere; Tsao, Daisy; Nieto, Andres; Lyda, Elizabeth; Meyer, Dodi; McCord, Mary

2014-01-01

Background: Obesity is a public health concern that disproportionately affects underserved and minority communities. Purpose: To evaluate whether a comprehensive obesity prevention program that targets children and school staff in an underserved Hispanic community affects obesity related knowledge, attitudes, and behaviors among both students and…

Assessing the spatial distribution of coral bleaching using small unmanned aerial systems

NASA Astrophysics Data System (ADS)

Levy, Joshua; Hunter, Cynthia; Lukacazyk, Trent; Franklin, Erik C.

2018-06-01

Small unmanned aerial systems (sUAS) are an affordable, effective complement to existing coral reef monitoring and assessment tools. sUAS provide repeatable low-altitude, high-resolution photogrammetry to address fundamental questions of spatial ecology and community dynamics for shallow coral reef ecosystems. Here, we qualitatively describe the use of sUAS to survey the spatial characteristics of coral cover and the distribution of coral bleaching across patch reefs in Kānéohe Bay, Hawaii, and address limitations and anticipated technology advancements within the field of UAS. Overlapping sub-decimeter low-altitude aerial reef imagery collected during the 2015 coral bleaching event was used to construct high-resolution reef image mosaics of coral bleaching responses on four Kānéohe Bay patch reefs, totaling 60,000 m2. Using sUAS imagery, we determined that paled, bleached and healthy corals on all four reefs were spatially clustered. Comparative analyses of data from sUAS imagery and in situ diver surveys found as much as 14% difference in coral cover values between survey methods, depending on the size of the reef and area surveyed. When comparing the abundance of unhealthy coral (paled and bleached) between sUAS and in situ diver surveys, we found differences in cover from 1 to 49%, depending on the depth of in situ surveys, the percent of reef area covered with sUAS surveys and patchiness of the bleaching response. This study demonstrates the effective use of sUAS surveys for assessing the spatial dynamics of coral bleaching at colony-scale resolutions across entire patch reefs and evaluates the complementarity of data from both sUAS and in situ diver surveys to more accurately characterize the spatial ecology of coral communities on reef flats and slopes.

Composition of Anopheline (Diptera: Culicidae) Community and Its Seasonal Variation in Three Environments of the City of Puerto Iguazú, Misiones, Argentina.

PubMed

Ramirez, P G; Stein, M; Etchepare, E G; Almirón, W R

2018-02-28

In order to extend the knowledge of the composition of the anopheline community and the seasonal variation related to anthropogenic modifications in the city of Puerto Iguazú, adult females were captured between 2009 and 2012. Samples were collected in three environments with different degrees of anthropogenic modification: urban, periurban, and wild. Alpha diversity was evaluated as the 'true' diversity of the species in each environment. Among environments, range-abundance curves were used to compare the composition, abundance, and uniformity of species and cluster analysis was used to analyze the similarities and differences. The temporal distribution was analyzed and the relative abundance of the species captured was correlated with meteorological variables. A total of 4,565 females, belonging to seven species: Anopheles albitarsis s.s. (Lynch-Arribálzaga), Anopheles argyritarsis (Robineau-Desvoidy), Anopheles deaneorum (Rosa-Freitas), Anopheles fluminensis (Root), Anopheles mediopunctatus (Theobald), Anopheles strodei s.l. (Root), and Anopheles triannulatus s.l. (Neiva and Pinto) were captured. The wild environment showed higher abundance, diversity, and greater uniformity reflected on the less sharp area of the range-abundance curve. Species richness was the same in the wild and periurban environments. Higher abundances were observed in summer during the months with higher temperatures. Although the wild environment showed greater Anopheles abundances and diversity, specific richness and species complementarity were similar among the three environments studied. Thus, the periurban environment would turn into a transition zone of great epidemiological importance due to the introduction of people in this environment, which represents a potential risk of malaria transmission in the area.

Constancy despite variability: Local and regional macrofaunal diversity in intertidal seagrass beds

NASA Astrophysics Data System (ADS)

Boyé, Aurélien; Legendre, Pierre; Grall, Jacques; Gauthier, Olivier

2017-12-01

The importance of seagrass habitat for the diversity of benthic fauna has been extensively studied worldwide. Most of the information available is, however, about α diversity while little consideration has been given to β diversity. To fill the knowledge gaps regarding the variability of epifaunal and infaunal seagrass assemblages at large spatial and temporal scales, we scrutinized an extensive dataset covering five years of monitoring of eight intertidal Zostera marina meadows around Brittany (France). High species richness arose at the regional scale from the combination of high local diversity of the meadows and substantial among-meadows β diversity. Epifauna and infauna appeared as distinct self-communities as they displayed different spatial and temporal patterns and varied in their responses to local hydrological conditions. Infauna had higher total β diversity than epifauna due to a tighter link to the great variability of local environmental conditions in the region. Both exhibited substantial variations in species composition and community structure with variations of dominant species that were accompanied by extensive change in numerous rare species. The dominant epifaunal species were all grazers. Changes in species composition were induced mostly by species replacement and rarely by richness differences between meadows. Indeed, species richness remained within a narrow range for all seagrass beds, suggesting a potential carrying capacity for species richness of the meadows. Overall, all meadows contributed equally to the regional turnover of seagrass macrofauna, emphasizing high variability and complementarity among beds at the regional scale. The implications of this substantial within-seagrass variability for the functioning of benthic ecosystems at broad scale and for conservation purposes in habitat mosaics warrant further investigations but our results clearly advocate taking into account within-habitat variation when evaluating the diversity of benthic habitats and the potential effect of habitat loss.

Experiences and lessons learned for delivery of micronutrient powders interventions.

PubMed

Reerink, Ietje; Namaste, Sorrel Ml; Poonawala, Alia; Nyhus Dhillon, Christina; Aburto, Nancy; Chaudhery, Deepika; Kroeun, Hou; Griffiths, Marcia; Haque, Mohammad Raisul; Bonvecchio, Anabelle; Jefferds, Maria Elena; Rawat, Rahul

2017-09-01

An effective delivery strategy coupled with relevant social and behaviour change communication (SBCC) have been identified as central to the implementation of micronutrient powders (MNP) interventions, but there has been limited documentation of what works. Under the auspices of "The Micronutrient Powders Consultation: Lessons Learned for Operational Guidance," three working groups were formed to summarize experiences and lessons across countries regarding MNP interventions for young children. This paper focuses on programmatic experiences related to MNP delivery (models, platforms, and channels), SBCC, and training. Methods included a review of published and grey literature, interviews with key informants, and deliberations throughout the consultation process. We found that most countries distributed MNP free of charge via the health sector, although distribution through other platforms and using subsidized fee for product or mixed payment models have also been used. Community-based distribution channels have generally shown higher coverage and when part of an infant and young child feeding approach, may provide additional benefit given their complementarity. SBCC for MNP has worked best when focused on meeting the MNP behavioural objectives (appropriate use, intake adherence, and related infant and young child feeding behaviours). Programmers have learned that reincorporating SBCC and training throughout the intervention life cycle has allowed for much needed adaptations. Diverse experiences delivering MNP exist, and although no one-size-fits-all approach emerged, well-established delivery platforms, community involvement, and SBCC-centred designs tended to have more success. Much still needs to be learned on MNP delivery, and we propose a set of implementation research questions that require further investigation. © 2017 The Authors. Maternal and Child Nutrition Published by John Wiley & Sons, Ltd.

Relationships among plants, soils and microbial communities along a hydrological gradient in the New Jersey Pinelands, USA

PubMed Central

Yu, Shen; Ehrenfeld, Joan G.

2010-01-01

Background and Aims Understanding the role of different components of hydrology in structuring wetland communities is not well developed. A sequence of adjacent wetlands located on a catenary sequence of soils and receiving the same sources and qualities of water is used to examine specifically the role of water-table median position and variability in affecting plant and microbial community composition and soil properties. Methods Two replicates of three types of wetland found adjacent to each other along a hydrological gradient in the New Jersey Pinelands (USA) were studied. Plant-community and water-table data were obtained within a 100-m2 plot in each community (pine swamp, maple swamp and Atlantic-white-cedar swamp). Monthly soil samples from each plot were analysed for soil moisture, organic matter, extractable nitrogen fractions, N mineralization rate and microbial community composition. Multivariate ordination methods were used to compare patterns among sites within and between data sets. Key Results The maple and pine wetlands were more similar to each other in plant community composition, soil properties and microbial community composition than either was to the cedar swamps. However, maple and pine wetlands differed from each other in water-table descriptors as much as they differed from the cedar swamps. All microbial communities were dominated by Gram-positive bacteria despite hydrologic differences among the sites. Water-table variability was as important as water-table level in affecting microbial communities. Conclusions Water tables affect wetland communities through both median level and variability. Differentiation of both plant and microbial communities are not simple transforms of differences in water-table position, even when other hydrologic factors are kept constant. Rather, soil genesis, a result of both water-table position and geologic history, appears to be the main factor affecting plant and microbial community similarities. PMID:19643908

Community-based participatory research in complex settings: clean mind–dirty hands

PubMed Central

Makhoul, Jihad; Nakkash, Rima; Harpham, Trudy; Qutteina, Yara

2014-01-01

Despite the abundance of the literature which discusses factors supporting or inhibiting effective participation of community members in community-based research, there is a paucity of publications analysing challenges to participation in complex settings. This manuscript describes an intervention built on researcher–community partnership amid complex social conditions which challenged participation of community members at different stages of the research process. The research took place in a Palestinian refugee camp in Beirut, Lebanon and 1 of 12 in Lebanon which suffer from deteriorating social, economic and physical conditions perpetuated by state-imposed restrictions. The research team developed a community coalition which was involved in all stages of planning, designing, implementation and dissemination. In all those stages the aim was to maintain rigorous research, to follow a ‘clean mind’ approach to research, but maintain principles of community participation which necessitate ‘a dirty hand’. Despite commitment to the principles of community-based participatory research, participation of community members (including youth, parents and teachers) was affected to a great extent by the social, physical and structural conditions of the community context. Characteristics of the context where research is conducted and how it affects community members should not be overlooked since multiple factors beyond the researchers' control could interfere with the rigour of scientific research. Researchers need to develop a plan for participation with the community from the beginning with an understanding of the community forces that affect meaningful participation and address possible deterrence. PMID:23872385

Ethnic groups' knowledge, attitude and practices and Rift Valley fever exposure in Isiolo County of Kenya.

PubMed

Affognon, Hippolyte; Mburu, Peter; Hassan, Osama Ahmed; Kingori, Sarah; Ahlm, Clas; Sang, Rosemary; Evander, Magnus

2017-03-01

Rift Valley fever (RVF) is an emerging mosquito-borne viral hemorrhagic fever in Africa and the Arabian Peninsula, affecting humans and livestock. For spread of infectious diseases, including RVF, knowledge, attitude and practices play an important role, and the understanding of the influence of behavior is crucial to improve prevention and control efforts. The objective of the study was to assess RVF exposure, in a multiethnic region in Kenya known to experience RVF outbreaks, from the behavior perspective. We investigated how communities in Isiolo County, Kenya were affected, in relation to their knowledge, attitude and practices, by the RVF outbreak of 2006/2007. A cross-sectional study was conducted involving 698 households selected randomly from three different ethnic communities. Data were collected using a structured questionnaire regarding knowledge, attitudes and practices that could affect the spread of RVF. In addition, information was collected from the communities regarding the number of humans and livestock affected during the RVF outbreak. This study found that better knowledge about a specific disease does not always translate to better practices to avoid exposure to the disease. However, the high knowledge, attitude and practice score measured as a single index of the Maasai community may explain why they were less affected, compared to other investigated communities (Borana and Turkana), by RVF during the 2006/2007 outbreak. We conclude that RVF exposure in Isiolo County, Kenya during the outbreak was likely determined by the behavioral differences of different resident community groups. We then recommend that strategies to combat RVF should take into consideration behavioral differences among communities.

Ethnic groups’ knowledge, attitude and practices and Rift Valley fever exposure in Isiolo County of Kenya

PubMed Central

Affognon, Hippolyte; Mburu, Peter; Hassan, Osama Ahmed; Kingori, Sarah; Ahlm, Clas; Sang, Rosemary; Evander, Magnus

2017-01-01

Rift Valley fever (RVF) is an emerging mosquito-borne viral hemorrhagic fever in Africa and the Arabian Peninsula, affecting humans and livestock. For spread of infectious diseases, including RVF, knowledge, attitude and practices play an important role, and the understanding of the influence of behavior is crucial to improve prevention and control efforts. The objective of the study was to assess RVF exposure, in a multiethnic region in Kenya known to experience RVF outbreaks, from the behavior perspective. We investigated how communities in Isiolo County, Kenya were affected, in relation to their knowledge, attitude and practices, by the RVF outbreak of 2006/2007. A cross-sectional study was conducted involving 698 households selected randomly from three different ethnic communities. Data were collected using a structured questionnaire regarding knowledge, attitudes and practices that could affect the spread of RVF. In addition, information was collected from the communities regarding the number of humans and livestock affected during the RVF outbreak. This study found that better knowledge about a specific disease does not always translate to better practices to avoid exposure to the disease. However, the high knowledge, attitude and practice score measured as a single index of the Maasai community may explain why they were less affected, compared to other investigated communities (Borana and Turkana), by RVF during the 2006/2007 outbreak. We conclude that RVF exposure in Isiolo County, Kenya during the outbreak was likely determined by the behavioral differences of different resident community groups. We then recommend that strategies to combat RVF should take into consideration behavioral differences among communities. PMID:28273071

Complementary methods to plan pedestrian evacuation of the French Riviera's beaches in case of tsunami threat: graph- and multi-agent-based modelling

NASA Astrophysics Data System (ADS)

Sahal, A.; Leone, F.; Péroche, M.

2013-07-01

Small amplitude tsunamis have impacted the French Mediterranean shore (French Riviera) in the past centuries. Some caused casualties; others only generated economic losses. While the North Atlantic and Mediterranean tsunami warning system is being tested and is almost operational, no awareness and preparedness measure is being implemented at a local scale. Evacuation is to be considered along the French Riviera, but no plan exists within communities. We show that various approaches can provide local stakeholders with evacuation capacities assessments to develop adapted evacuation plans through the case study of the Cannes-Antibes region. The complementarity between large- and small-scale approaches is demonstrated with the use of macro-simulators (graph-based) and micro-simulators (multi-agent-based) to select shelter points and choose evacuation routes for pedestrians located on the beach. The first one allows automatically selecting shelter points and measuring and mapping their accessibility. The second one shows potential congestion issues during pedestrian evacuations, and provides leads for the improvement of urban environment. Temporal accessibility to shelters is compared to potential local and distal tsunami travel times, showing a 40 min deficit for an adequate crisis management in the first scenario, and a 30 min surplus for the second one.

Ectomycorrhizal fungal diversity increases phosphorus uptake efficiency of European beech.

PubMed

Köhler, Julia; Yang, Nan; Pena, Rodica; Raghavan, Venket; Polle, Andrea; Meier, Ina C

2018-05-17

Increases in summer droughts and nitrogen (N) deposition have raised concerns of widespread biodiversity loss and nutrient imbalances, but our understanding of the ecological role of ectomycorrhizal fungal (ECMF) diversity in mediating root functions remains a major knowledge gap. We used different global change scenarios to experimentally alter the composition of ECMF communities colonizing European beech saplings and examined the consequences for phosphorus (P) uptake (H 3 33 PO 4 feeding experiment) and use efficiencies of trees. Specifically, we simulated increases in temperature and N deposition and decreases in soil moisture and P availability in a factorial experiment. Here, we show that ECMF α diversity is a major factor contributing to root functioning under global change. P uptake efficiency of beech significantly increased with increasing ECMF species richness and diversity, as well as with decreasing P availability. As a consequence of decreases in ECMF diversity, P uptake efficiency decreased when soil moisture was limiting. By contrast, P use efficiencies were a direct (negative) function of P availability and not of ECMF diversity. We conclude that increasing summer droughts may reduce ECMF diversity and the complementarity of P uptake by ECMF species, which will add to negative growth effects expected from nutrient imbalances under global change. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Accounting for soil biotic effects on soil health and crop productivity in the design of crop rotations.

PubMed

Dias, Teresa; Dukes, Angela; Antunes, Pedro M

2015-02-01

There is an urgent need for novel agronomic improvements capable of boosting crop yields while alleviating environmental impacts. One such approach is the use of optimized crop rotations. However, a set of measurements that can serve as guiding principles for the design of crop rotations is lacking. Crop rotations take advantage of niche complementarity, enabling the optimization of nutrient use and the reduction of pests and specialist pathogen loads. However, despite the recognized importance of plant-soil microbial interactions and feedbacks for crop yield and soil health, this is ignored in the selection and management of crops for rotation systems. We review the literature and propose criteria for the design of crop rotations focusing on the roles of soil biota and feedback on crop productivity and soil health. We consider that identifying specific key organisms or consortia capable of influencing plant productivity is more important as a predictor of soil health and crop productivity than assessing the overall soil microbial diversity per se. As such, we propose that setting up soil feedback studies and applying genetic sequencing tools towards the development of soil biotic community databases has a strong potential to enable the establishment of improved soil health indicators for optimized crop rotations. © 2014 Society of Chemical Industry.

Elements of well-being affected by criminalizing the drug user.

PubMed Central

Iguchi, Martin Y.; London, Jennifer A.; Forge, Nell Griffith; Hickman, Laura; Fain, Terry; Riehman, Kara

2002-01-01

OBJECTIVE: The authors examine the possible adverse consequences of incarceration on drug offenders, their families, and their communities. OBSERVATIONS: State and federal policies on drug felons may affect eight elements of personal and community well-being: children and families, access to health benefits, access to housing benefits, access to assistance for higher education, immigration status, employment, eligibility to vote, and drug use or recidivism. CONCLUSIONS: Minorities have a high chance of felony conviction and an increasing lack of access to resources, suggesting that patterns of drug conviction and health disparities may be mutually reinforcing. Large numbers of people sent to prison for drug offenses are now completing their terms and reentering communities. Their reentry will disproportionately affect minority communities. Without resources (education, job opportunities, insurance, health care, housing, and the right to vote) drug abusers face a higher risk of recidivism and increase the burden on their communities. PMID:12435838

Is It More Feeling or Thinking? The Influence of Affective and Cognitive Attitude on Adolescents' Intention to Engage in Binge Drinking.

PubMed

Boers, Elroy; Zebregs, Simon; Hendriks, Hanneke; Van Den Putte, Bas

2018-04-25

Previous work has revealed that interventions aiming to reduce adolescent binge drinking commonly focus on cognitive attitudes, but are insufficiently effective in changing binge-drinking intentions. The focus on these cognitive attitudes might be the reason for this insufficient success. That is, other work has revealed that affective attitudes have a stronger influence on binge-drinking intention than cognitive attitudes. However, this relation has so far only been found among traditional college students and pre-vocational school students, therewith neglecting another important population at risk, namely vocational community college students. This study examines whether affective attitudes are also significantly stronger influencers of binge-drinking intentions among vocational community college students. Using a sample of 298 vocational community college students (M age  = 17.63), the current study shows that affective attitudes were more strongly related to vocational community college students' intention to engage in binge drinking than cognitive attitudes. This finding indicates that the effectiveness of interventions targeting adolescent binge drinking can be improved by incorporating content elements concerning affective attitudes.

Principles of Chemical Biology: From Sexy Fatty Acids and EBV probes to Anti-Acid Antibiotic via Post-Biotics and Host-Microbe Metabolic Complementarity.

PubMed

2017-06-22

This month: The role of fatty acids in sex determination; a probe to monitor and inhibit EBNA1 at the same time; a biological role for post-biotics; what happens when you mix microbes, hosts, and drugs; and an antibiotic that cross-protects with acid. Copyright © 2017. Published by Elsevier Ltd.

De la dualite a la complementaire: Le cas du bilingualisme au Maroc (From Duality to Complementarity: The Case of Bilingualism in Morocco).

ERIC Educational Resources Information Center

Redouane, Rabia

1998-01-01

Discusses the case of bilingualism in Morocco, a territory where a large variety of languages intersect, including French, Arabic, and Tamazight. The contact of cultures articulated through these languages allows Morocco to assign value to bilingualism that is not perceived as rivalry but as complementing the development of modern cosmopolitan…

From Contradictions to Complementarities: A Social Realist Analysis of the Evolution of Academic Development within a Department

ERIC Educational Resources Information Center

Case, Jennifer M.; Heydenrych, Hilton; Kotta, Linda; Marshall, Delia; McKenna, Sioux; Williams, Kevin

2017-01-01

Academic development is a recent project in the university, intended to enable the university to respond to the needs of a more diverse student body. In South Africa, such work arose during late apartheid, and has now moved to a more central institutional position advocating responsiveness in the light of the educational disparities that are the…

Automating Performance Measures and Clinical Practice Guidelines: Differences and Complementarities.

PubMed

Tu, Samson W; Martins, Susana; Oshiro, Connie; Yuen, Kaeli; Wang, Dan; Robinson, Amy; Ashcraft, Michael; Heidenreich, Paul A; Goldstein, Mary K

2016-01-01

Through close analysis of two pairs of systems that implement the automated evaluation of performance measures (PMs) and guideline-based clinical decision support (CDS), we contrast differences in their knowledge encoding and necessary changes to a CDS system that provides management recommendations for patients failing performance measures. We trace the sources of differences to the implementation environments and goals of PMs and CDS.

Let's get specific: the relationship between specificity and affinity.

PubMed

Eaton, B E; Gold, L; Zichi, D A

1995-10-01

The factors that lead to high-affinity binding are a good fit between the surfaces of the two molecules in their ground state and charge complementarity. Exactly the same factors give high specificity for a target. We argue that selection for high-affinity binding automatically leads to highly specific binding. This principle can be used to simplify screening approaches aimed at generating useful drugs.

Analysis of the Alkali Metal Diatomic Spectra; Using molecular beams and ultracold molecules

NASA Astrophysics Data System (ADS)

Kim, Jin-Tae

2014-12-01

This ebook illustrates the complementarity of molecular beam (MB) spectra and ultracold molecule (UM) spectra in unraveling the complex electronic spectra of diatomic alkali metal molecules, using KRb as a prime example. Researchers interested in molecular spectroscopy, whether physicist, chemist, or engineer, may find this ebook helpful and may be able to apply similar ideas to their molecules of interest.

Lexicality, Morphological Structure, and Semantic Transparency in the Processing of German Ver-Verbs: The Complementarity of On-Line and Off-Line Evidence

ERIC Educational Resources Information Center

Schirmeier, Matthias K.; Derwing, Bruce L.; Libben, Gary

2004-01-01

Two types of experiments investigate the visual on-line and off-line processing of German ver-verbs (e.g., verbittern "to embitte"). In Experiments 1 and 2 (morphological priming), latency patterns revealed the existence of facilitation effects for the morphological conditions (BITTER-VERBITTERN and BITTERN-VERBITTERN) as compared to the neutral…

Multi-period equilibrium/near-equilibrium in electricity markets based on locational marginal prices

NASA Astrophysics Data System (ADS)

Garcia Bertrand, Raquel

In this dissertation we propose an equilibrium procedure that coordinates the point of view of every market agent resulting in an equilibrium that simultaneously maximizes the independent objective of every market agent and satisfies network constraints. Therefore, the activities of the generating companies, consumers and an independent system operator are modeled: (1) The generating companies seek to maximize profits by specifying hourly step functions of productions and minimum selling prices, and bounds on productions. (2) The goals of the consumers are to maximize their economic utilities by specifying hourly step functions of demands and maximum buying prices, and bounds on demands. (3) The independent system operator then clears the market taking into account consistency conditions as well as capacity and line losses so as to achieve maximum social welfare. Then, we approach this equilibrium problem using complementarity theory in order to have the capability of imposing constraints on dual variables, i.e., on prices, such as minimum profit conditions for the generating units or maximum cost conditions for the consumers. In this way, given the form of the individual optimization problems, the Karush-Kuhn-Tucker conditions for the generating companies, the consumers and the independent system operator are both necessary and sufficient. The simultaneous solution to all these conditions constitutes a mixed linear complementarity problem. We include minimum profit constraints imposed by the units in the market equilibrium model. These constraints are added as additional constraints to the equivalent quadratic programming problem of the mixed linear complementarity problem previously described. For the sake of clarity, the proposed equilibrium or near-equilibrium is first developed for the particular case considering only one time period. Afterwards, we consider an equilibrium or near-equilibrium applied to a multi-period framework. This model embodies binary decisions, i.e., on/off status for the units, and therefore optimality conditions cannot be directly applied. To avoid limitations provoked by binary variables, while retaining the advantages of using optimality conditions, we define the multi-period market equilibrium using Benders decomposition, which allows computing binary variables through the master problem and continuous variables through the subproblem. Finally, we illustrate these market equilibrium concepts through several case studies.

From correspondence to complementarity: The emergence of Bohr's Copenhagen interpretation of quantum mechanics

NASA Astrophysics Data System (ADS)

Tanona, Scott Daniel

I develop a new analysis of Niels Bohr's Copenhagen interpretation of quantum mechanics by examining the development of his views from his earlier use of the correspondence principle in the so-called 'old quantum theory' to his articulation of the idea of complementarity in the context of the novel mathematical formalism of quantum mechanics. I argue that Bohr was motivated not by controversial and perhaps dispensable epistemological ideas---positivism or neo-Kantianism, for example---but by his own unique perspective on the difficulties of creating a new working physics of the internal structure of the atom. Bohr's use of the correspondence principle in the old quantum theory was associated with an empirical methodology that used this principle as an epistemological bridge to connect empirical phenomena with quantum models. The application of the correspondence principle required that one determine the validity of the idealizations and approximations necessary for the judicious use of classical physics within quantum theory. Bohr's interpretation of the new quantum mechanics then focused on the largely unexamined ways in which the developing abstract mathematical formalism is given empirical content by precisely this process of approximation. Significant consistency between his later interpretive framework and his forms of argument with the correspondence principle indicate that complementarity is best understood as a relationship among the various approximations and idealizations that must be made when one connects otherwise meaningless quantum mechanical symbols to empirical situations or 'experimental arrangements' described using concepts from classical physics. We discover that this relationship is unavoidable not through any sort of a priori analysis of the priority of classical concepts, but because quantum mechanics incorporates the correspondence approach in the way in which it represents quantum properties with matrices of transition probabilities, the empirical meaning of which depend on the situation but in general are tied to the correspondence connection to the spectra. For Bohr, it is then the commutation relations, which arise from the formalism, which inform us of the complementary nature of this approximate representation of quantum properties via the classical equations through which we connect them to experiments.

How has the economic downturn affected communities and implementation of science-based prevention in the randomized trial of communities that care?

PubMed

Kuklinski, Margaret R; Hawkins, J David; Plotnick, Robert D; Abbott, Robert D; Reid, Carolina K

2013-06-01

This study examined implications of the economic downturn that began in December 2007 for the Community Youth Development Study (CYDS), a longitudinal randomized controlled trial of the Communities That Care (CTC) prevention system. The downturn had the potential to affect the internal validity of the CYDS research design and implementation of science-based prevention in study communities. We used archival economic indicators and community key leader reports of economic conditions to assess the extent of the economic downturn in CYDS communities and potential internal validity threats. We also examined whether stronger economic downturn effects were associated with a decline in science-based prevention implementation. Economic indicators suggested the downturn affected CYDS communities to different degrees. We found no evidence of systematic differences in downturn effects in CTC compared to control communities that would threaten internal validity of the randomized trial. The Community Economic Problems scale was a reliable measure of community economic conditions, and it showed criterion validity in relation to several objective economic indicators. CTC coalitions continued to implement science-based prevention to a significantly greater degree than control coalitions 2 years after the downturn began. However, CTC implementation levels declined to some extent as unemployment, the percentage of students qualifying for free lunch, and community economic problems worsened. Control coalition implementation levels were not related to economic conditions before or after the downturn, but mean implementation levels of science-based prevention were also relatively low in both periods.

How Has the Economic Downturn Affected Communities and Implementation of Science-Based Prevention in the Randomized Trial of Communities That Care?

PubMed Central

Kuklinski, Margaret R.; Hawkins, J. David; Plotnick, Robert D.; Abbott, Robert D.; Reid, Carolina K.

2013-01-01

This study examined implications of the economic downturn that began in December 2007 for the Community Youth Development Study (CYDS), a longitudinal randomized controlled trial of the Communities That Care (CTC) prevention system. The downturn had the potential to affect the internal validity of the CYDS research design and implementation of science-based prevention in study communities. We used archival economic indicators and community key leader reports of economic conditions to assess the extent of the economic downturn in CYDS communities and potential internal validity threats. We also examined whether stronger economic downturn effects were associated with a decline in science-based prevention implementation. Economic indicators suggested the downturn affected CYDS communities to different degrees. We found no evidence of systematic differences in downturn effects in CTC compared to control communities that would threaten internal validity of the randomized trial. The Community Economic Problems scale was a reliable measure of community economic conditions, and it showed criterion validity in relation to several objective economic indicators. CTC coalitions continued to implement science-based prevention to a significantly greater degree than control coalitions 2 years after the downturn began. However, CTC implementation levels declined to some extent as unemployment, the percentage of students qualifying for free lunch, and community economic problems worsened. Control coalition implementation levels were not related to economic conditions before or after the downturn, but mean implementation levels of science-based prevention were also relatively low in both periods. PMID:23054169

As Far as the Eye Can See: Relationship between Psychopathic Traits and Pupil Response to Affective Stimuli

PubMed Central

Gray, Nicola S.; Snowden, Robert J.

2017-01-01

Psychopathic individuals show a range of affective processing deficits, typically associated with the interpersonal/affective component of psychopathy. However, previous research has been inconsistent as to whether psychopathy, within both offender and community populations, is associated with deficient autonomic responses to the simple presentation of affective stimuli. Changes in pupil diameter occur in response to emotionally arousing stimuli and can be used as an objective indicator of physiological reactivity to emotion. This study used pupillometry to explore whether psychopathic traits within a community sample were associated with hypo-responsivity to the affective content of stimuli. Pupil activity was recorded for 102 adult (52 female) community participants in response to affective (both negative and positive affect) and affectively neutral stimuli, that included images of scenes, static facial expressions, dynamic facial expressions and sound-clips. Psychopathic traits were measured using the Triarchic Psychopathy Measure. Pupil diameter was larger in response to negative stimuli, but comparable pupil size was demonstrated across pleasant and neutral stimuli. A linear relationship between subjective arousal and pupil diameter was found in response to sound-clips, but was not evident in response to scenes. Contrary to predictions, psychopathy was unrelated to emotional modulation of pupil diameter across all stimuli. The findings were the same when participant gender was considered. This suggests that psychopathy within a community sample is not associated with autonomic hypo-responsivity to affective stimuli, and this effect is discussed in relation to later defensive/appetitive mobilisation deficits. PMID:28118366

Do recreational activities affect coastal biodiversity?

NASA Astrophysics Data System (ADS)

Riera, Rodrigo; Menci, Cristiano; Sanabria-Fernández, José Antonio; Becerro, Mikel A.

2016-09-01

Human activities are largely affecting coastal communities worldwide. Recreational perturbations have been overlooked in comparison to other perturbations, yet they are potential threats to marine biodiversity. They affect coastal communities in different ways, underpinning consistent shifts in fish and invertebrates assemblages. Several sites were sampled subjected to varying effects by recreational fishermen (low and high pressure) and scuba divers (low and high) in an overpopulated Atlantic island. Non-consistent differences in ecological, trophic and functional diversity were found in coastal communities, considering both factors (;diving; and ;fishing;). Multivariate analyses only showed significant differences in benthic invertebrates between intensively-dived and non-dived sites. The lack of clear trends may be explained by the depletion of coastal resources in the study area, an extensively-affected island by overfishing.

Assessing effects of the entomopathogenic fungus Metarhizium brunneum on soil microbial communities in Agriotes spp. biological pest control.

PubMed

Mayerhofer, Johanna; Eckard, Sonja; Hartmann, Martin; Grabenweger, Giselher; Widmer, Franco; Leuchtmann, Adrian; Enkerli, Jürg

2017-10-01

The release of large quantities of microorganisms to soil for purposes such as pest control or plant growth promotion may affect the indigenous soil microbial communities. In our study, we investigated potential effects of Metarhizium brunneum ART2825 on soil fungi and prokaryota in bulk soil using high-throughput sequencing of ribosomal markers. Different formulations of this strain, and combinations of the fungus with garlic as efficacy-enhancing agent, were tested over 4 months in a pot and a field experiment carried out for biological control of Agriotes spp. in potatoes. A biocontrol effect was observed only in the pot experiment, i.e. the application of FCBK resulted in 77% efficacy. Colony counts combined with genotyping and marker sequence abundance confirmed the successful establishment of the applied strain. Only the formulated applied strain caused small shifts in fungal communities in the pot experiment. Treatment effects were in the same range as the effects caused by barley kernels, the carrier of the FCBK formulation and temporal effects. Garlic treatments and time affected prokaryotic communities. In the field experiment, only spatial differences affected fungal and prokaryotic communities. Our findings suggest that M. brunneum may not adversely affect soil microbial communities. © FEMS 2017.

Apple orchard pest control strategies affect bird communities in southeastern France.

PubMed

Bouvier, Jean-Charles; Ricci, Benoît; Agerberg, Julia; Lavigne, Claire

2011-01-01

Birds are regarded as appropriate biological indicators of how changes in agricultural practices affect the environment. They are also involved in the biocontrol of pests. In the present study, we provide an assessment of the impact of pest control strategies on bird communities in apple orchards in southeastern France. We compared the structure (abundance, species richness, and diversity) of breeding bird communities in 15 orchards under conventional or organic pest control over a three-year period (2003-2005). Pest control strategies and their evolution over time were characterized by analyzing farmers' treatment schedules. The landscape surrounding the orchards was characterized using a Geographic Information System. We observed 30 bird species overall. Bird abundance, species richness, and diversity were all affected by pest control strategies, and were highest in organic orchards and lowest in conventional orchards during the three study years. The pest control strategy affected insectivores more than granivores. We further observed a tendency for bird communities in integrated pest management orchards to change over time and become increasingly different from communities in organic orchards, which also corresponded to changes in treatment schedules. These findings indicate that within-orchard bird communities may respond quickly to changes in pesticide use and may, in turn, influence biocontrol of pests by birds. © 2010 SETAC.

Predator community structure and trophic linkage strength to a focal prey.

PubMed

Lundgren, Jonathan G; Fergen, Janet K

2014-08-01

Predator abundance and community structure can affect the suppression of lower trophic levels, although studies of these interactions under field conditions are relatively few. We investigated how the frequency of consumption (measured using PCR-based gut content analysis) is affected by predator abundance, community diversity and evenness under realistic conditions. Soil arthropod communities in sixteen maize fields were measured (number of predators, diversity [Shannon H] and evenness [J]), and predator guts were searched for DNA of the focal subterranean herbivore, the corn rootworm (Diabrotica virgifera). Predator abundance and diversity were positively correlated with trophic linkage strength (the proportion positive for rootworm DNA), although the latter characteristic was not significantly so. The diversity and evenness of the predator community with chewing mouthparts were strongly correlated with their linkage strength to rootworms, whereas the linkage strength of fluid-feeding predators was unaffected by their community characteristics. Within this community, chewing predators are more affected by the rootworm's hemolymph defence. This research clearly shows that predator abundance and diversity influence the strength of a community's trophic linkage to a focal pest and that these community characteristics may be particularly important for less palatable or protected prey species. We also make the case for conserving diverse and abundant predator communities within agroecosystems as a form of pest management. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Context and group dynamics in a CBPR-developed HIV prevention intervention

PubMed Central

Dickson-Gomez, Julia; Corbett, A. Michelle; Bodnar, Gloria; Zuniga, Maria Ofelia; Guevara, Carmen Eugenia; Rodriguez, Karla; Navas, Verónica

2016-01-01

This paper will explore in detail the effects of context and group dynamics on the development of a multi-level community-based HIV prevention intervention for crack cocaine users in the San Salvador Metropolitan Area, El Salvador. Community partners included residents from marginal communities, service providers from the historic center of San Salvador and research staff from a non-profit organization. The community contexts from which partners came varied considerably and affected structural group dynamics, i.e. who was identified as community partners, their research and organizational capacity, and their ability to represent their communities, with participants from marginal communities most likely to hold community leadership positions and be residents, and those from the center of San Salvador most likely to work in religious organizations dedicated to HIV prevention or feeding indigent drug users. These differences also affected the intervention priorities of different partners. The context of communities changed over time, particularly levels of violence, and affected group dynamics and the intervention developed. Finally, strategies were needed to elicit input from stakeholders under-represented in the community advisory board, in particular active crack users, in order to check the feasibility of the proposed intervention and revise it as necessary. Because El Salvador is a very different context than that in which most CBPR studies have been conducted, our results reveal important contextual factors and their effects on partnerships not often considered in the literature. PMID:25070835

Experimental parasite community ecology: intraspecific variation in a large tapeworm affects community assembly.

PubMed

Benesh, Daniel P; Kalbe, Martin

2016-07-01

Non-random species associations occur in naturally sampled parasite communities. The processes resulting in predictable community structure (e.g. particular host behaviours, cross-immunity, interspecific competition) could be affected by traits that vary within a parasite species, like growth or antigenicity. We experimentally infected three-spined sticklebacks with a large tapeworm (Schistocephalus solidus) that impacts the energy needs, foraging behaviour and immune reactions of its host. The tapeworms came from two populations, characterized by high or low growth in sticklebacks. Our goal was to evaluate how this parasite, and variation in its growth, affects the acquisition of other parasites. Fish infected with S. solidus were placed into cages in a lake to expose them to the natural parasite community. We also performed a laboratory experiment in which infected fish were exposed to a fixed dose of a common trematode parasite. In the field experiment, infection with S. solidus affected the abundance of four parasite species, relative to controls. For two of the four species, changes occurred only in fish harbouring the high-growth S. solidus; one species increased in abundance and the other decreased. These changes did not appear to be directly linked to S. solidus growth though. The parasite exhibiting elevated abundance was the same trematode used in the laboratory infection. In that experiment, we found a similar infection pattern, suggesting that S. solidus affects the physiological susceptibility of fish to this trematode. Associations between S. solidus and other parasites occur and vary in direction. However, some of these associations were contingent on the S. solidus population, suggesting that intraspecific variability can affect the assembly of parasite communities. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Open Tools for Integrated Modelling to Understand SDG development - The OPTIMUS program

NASA Astrophysics Data System (ADS)

Howells, Mark; Zepeda, Eduardo; Rogner, H. Holger; Sanchez, Marco; Roehrl, Alexander; Cicowiez, Matrin; Mentis, Dimitris; Korkevelos, Alexandros; Taliotis, Constantinos; Broad, Oliver; Alfstad, Thomas

2016-04-01

The recently adopted Sustainable Development Goals (SDGs) - a set of 17 measurable and time-bound goals with 169 associated targets for 2030 - are highly inclusive challenges before the world community ranging from eliminating poverty to human rights, inequality, a secure world and protection of the environment. Each individual goal or target by themselves present enormous tasks, taken together they are overwhelming. There strong and weak interlinkages, hence trade-offs and complementarities among goals and targets. Some targets may affect several goals while other goals and targets may conflict or be mutually exclusive (Ref). Meeting each of these requires the judicious exploitation of resource, with energy playing an important role. Such complexity demands to be addressed in an integrated way using systems analysis tools to support informed policy formulation, planning, allocation of scarce resources, monitoring progress, effectiveness and review at different scales. There is no one size fits all methodology that conceivably could include all goal and targets simultaneously. But there are methodologies encapsulating critical subsets of the goal and targets with strong interlinkages with a 'soft' reflection on the weak interlinkages. Universal food security or sustainable energy for all inherently support goals and targets on human rights and equality but possibly at the cost of biodiversity or desertification. Integrated analysis and planning tools are not yet commonplace at national universities - or indeed in many policy making organs. What is needed is a fundamental realignment of institutions and integrations of their planning processes and decision making. We introduce a series of open source tools to support the SDG planning and implementation process. The Global User-friendly CLEW Open Source (GLUCOSE) tool optimizes resource interactions and constraints; The Global Electrification Tool kit (GETit) provides the first global spatially explicit electrification simulator; A national CLEW tool allows for the optimization of national level integrated resource use and Macro-CLEW presents the same allowing for detailed economic-biophysical interactions. Finally open Model Management Infrastructure (MoManI) is presented that allows for the rapid prototyping of new additions to, or new resource optimization tools. Collectively these tools provide insights to some fifteen of the SDGs and are made publicly available with support to governments and academic institutions.

Modularity, pollination systems, and interaction turnover in plant-pollinator networks across space.

PubMed

Carstensen, Daniel W; Sabatino, Malena; Morellato, Leonor Patricia C

2016-05-01

Mutualistic interaction networks have been shown to be structurally conserved over space and time while pairwise interactions show high variability. In such networks, modularity is the division of species into compartments, or modules, where species within modules share more interactions with each other than they do with species from other modules. Such a modular structure is common in mutualistic networks and several evolutionary and ecological mechanisms have been proposed as underlying drivers. One prominent explanation is the existence of pollination syndromes where flowers tend to attract certain pollinators as determined by a set of traits. We investigate the modularity of seven community level plant-pollinator networks sampled in rupestrian grasslands, or campos rupestres, in SE Brazil. Defining pollination systems as corresponding groups of flower syndromes and pollinator functional groups, we test the two hypotheses that (1) interacting species from the same pollination system are more often assigned to the same module than interacting species from different pollination systems and; that (2) interactions between species from the same pollination system are more consistent across space than interactions between species from different pollination systems. Specifically we ask (1) whether networks are consistently modular across space; (2) whether interactions among species of the same pollination system occur more often inside modules, compared to interactions among species of different pollination systems, and finally; (3) whether the spatial variation in interaction identity, i.e., spatial interaction rewiring, is affected by trait complementarity among species as indicated by pollination systems. We confirm that networks are consistently modular across space and that interactions within pollination systems principally occur inside modules. Despite a strong tendency, we did not find a significant effect of pollination systems on the spatial consistency of pairwise interactions. These results indicate that the spatial rewiring of interactions could be constrained by pollination systems, resulting in conserved network structures in spite of high variation in pairwise interactions. Our findings suggest a relevant role of pollination systems in structuring plant-pollinator networks and we argue that structural patterns at the sub-network level can help us to fully understand how and why interactions vary across space and time.

Community characteristics as predictors of perceived HMO quality.

PubMed

Ahern, M M; Hendryx, M S

1998-06-01

We model the impact of community characteristics on people's perceptions of the quality of their health care experiences in HMOs. We focus on three community characteristics: sense of community, population density, and population diversity. Sense of community refers to people's perception of interconnection, shared responsibility, and common goals. Population density and population diversity are community characteristics that affect transactions costs in terms of time and energy, and affect people's perceptions of their community. We use data from a 1993 Florida poll to estimate the relationship between HMO members' perceptions of problems with health care experiences (cost, choice, access, satisfaction) and community characteristics. We find that all three community variables are significantly associated with perceptions of health care problems. We also find that effects of community variables operate differently for those in HMOs vs. those under traditional insurance. This study is consistent with research showing that community characteristics impact the health status of community institutions. Results suggest that providers may be able to improve care by being more responsive to individuals' need for community, that providers and communities can mutually gain by collaborating to improve community health, and that it may be cost-beneficial to factor community issues more strongly into health care policy.

Experimentally altered rainfall regimes and host root traits affect grassland arbuscular mycorrhizal fungal communities.

PubMed

Deveautour, Coline; Donn, Suzanne; Power, Sally A; Bennett, Alison E; Powell, Jeff R

2018-04-01

Future climate scenarios predict changes in rainfall regimes. These changes are expected to affect plants via effects on the expression of root traits associated with water and nutrient uptake. Associated microorganisms may also respond to these new precipitation regimes, either directly in response to changes in the soil environment or indirectly in response to altered root trait expression. We characterized arbuscular mycorrhizal (AM) fungal communities in an Australian grassland exposed to experimentally altered rainfall regimes. We used Illumina sequencing to assess the responses of AM fungal communities associated with four plant species sampled in different watering treatments and evaluated the extent to which shifts were associated with changes in root traits. We observed that altered rainfall regimes affected the composition but not the richness of the AM fungal communities, and we found distinctive communities in the increased rainfall treatment. We found no evidence of altered rainfall regime effects via changes in host physiology because none of the studied traits were affected by changes in rainfall. However, specific root length was observed to correlate with AM fungal richness, while concentrations of phosphorus and calcium in root tissue and the proportion of root length allocated to fine roots were correlated to community composition. Our study provides evidence that climate change and its effects on rainfall may influence AM fungal community assembly, as do plant traits related to plant nutrition and water uptake. We did not find evidence that host responses to altered rainfall drive AM fungal community assembly in this grassland ecosystem. © 2018 John Wiley & Sons Ltd.

Determinants of community structure of zooplankton in heavily polluted river ecosystems

NASA Astrophysics Data System (ADS)

Xiong, Wei; Li, Jie; Chen, Yiyong; Shan, Baoqing; Wang, Weimin; Zhan, Aibin

2016-02-01

River ecosystems are among the most affected habitats globally by human activities, such as the release of chemical pollutants. However, it remains largely unknown how and to what extent many communities such as zooplankton are affected by these environmental stressors in river ecosystems. Here, we aim to determine major factors responsible for shaping community structure of zooplankton in heavily polluted river ecosystems. Specially, we use rotifers in the Haihe River Basin (HRB) in North China as a case study to test the hypothesis that species sorting (i.e. species are “filtered” by environmental factors and occur at environmental suitable sites) plays a key role in determining community structure at the basin level. Based on an analysis of 94 sites across the plain region of HRB, we found evidence that both local and regional factors could affect rotifer community structure. Interestingly, further analyses indicated that local factors played a more important role in determining community structure. Thus, our results support the species sorting hypothesis in highly polluted rivers, suggesting that local environmental constraints, such as environmental pollution caused by human activities, can be stronger than dispersal limitation caused by regional factors to shape local community structure of zooplankton at the basin level.

Five questiouns dentists should ask about their money. Question 4: how do the communities (family, practice, profession, culture, neighborhood, etc.) in which I live affect my financial decisions?

PubMed

Jones, Troy E

2006-11-01

Communities, and the personal value you place on them, affect all your spending, both business and personal. Once you begin questioning and analyzing how they affect your financial decisions, you will begin making more complete choices - the better-informed, the greater chance of success. Society has attached many financial expectations to dentists - both good and bad. By participating in this part of the Five Questions process, you will be able to separate the business of dentistry from the practice of dentistry and your persona beliefs from the beliefs of your communities'.

Strengthening the network of mentored, underrepresented minority scientists and leaders to reduce HIV-related health disparities.

PubMed

Sutton, Madeline Y; Lanier, Yzette A; Willis, Leigh A; Castellanos, Ted; Dominguez, Ken; Fitzpatrick, Lisa; Miller, Kim S

2013-12-01

We reviewed data for the Minority HIV/AIDS Research Initiative (MARI), which was established in 2003 to support underrepresented minority scientists performing HIV prevention research in highly affected communities. MARI was established at the Centers for Disease Prevention and Control as a program of competitively awarded, mentored grants for early career researchers conducting HIV prevention research in highly affected racial/ethnic and sexual minority communities. We have described progress from 2003 to 2013. To date, MARI has mentored 27 scientist leaders using low-cost strategies to enhance the development of effective HIV prevention interventions. These scientists have (1) developed research programs in disproportionately affected communities of color, (2) produced first-authored peer-reviewed scientific and programmatic products (including articles and community-level interventions), and (3) obtained larger, subsequent funding awards for research and programmatic work related to HIV prevention and health disparities work. The MARI program demonstrates how to effectively engage minority scientists to conduct HIV prevention research and reduce racial/ethnic investigator disparities and serves as a model for programs to reduce disparities in other public health areas in which communities of color are disproportionately affected.

Strengthening the Network of Mentored, Underrepresented Minority Scientists and Leaders to Reduce HIV-Related Health Disparities

PubMed Central

Lanier, Yzette A.; Willis, Leigh A.; Castellanos, Ted; Dominguez, Ken; Fitzpatrick, Lisa; Miller, Kim S.

2013-01-01

Objectives. We reviewed data for the Minority HIV/AIDS Research Initiative (MARI), which was established in 2003 to support underrepresented minority scientists performing HIV prevention research in highly affected communities. Methods. MARI was established at the Centers for Disease Prevention and Control as a program of competitively awarded, mentored grants for early career researchers conducting HIV prevention research in highly affected racial/ethnic and sexual minority communities. We have described progress from 2003 to 2013. Results. To date, MARI has mentored 27 scientist leaders using low-cost strategies to enhance the development of effective HIV prevention interventions. These scientists have (1) developed research programs in disproportionately affected communities of color, (2) produced first-authored peer-reviewed scientific and programmatic products (including articles and community-level interventions), and (3) obtained larger, subsequent funding awards for research and programmatic work related to HIV prevention and health disparities work. Conclusions. The MARI program demonstrates how to effectively engage minority scientists to conduct HIV prevention research and reduce racial/ethnic investigator disparities and serves as a model for programs to reduce disparities in other public health areas in which communities of color are disproportionately affected. PMID:24134360

UV sensitivity of planktonic net community production in ocean surface waters

NASA Astrophysics Data System (ADS)

Regaudie-de-Gioux, Aurore; Agustí, Susana; Duarte, Carlos M.

2014-05-01

The net plankton community metabolism of oceanic surface waters is particularly important as it more directly affects the partial pressure of CO2 in surface waters and thus the air-sea fluxes of CO2. Plankton communities in surface waters are exposed to high irradiance that includes significant ultraviolet blue (UVB, 280-315 nm) radiation. UVB radiation affects both photosynthetic and respiration rates, increase plankton mortality rates, and other metabolic and chemical processes. Here we test the sensitivity of net community production (NCP) to UVB of planktonic communities in surface waters across contrasting regions of the ocean. We observed here that UVB radiation affects net plankton community production at the ocean surface, imposing a shift in NCP by, on average, 50% relative to the values measured when excluding partly UVB. Our results show that under full solar radiation, the metabolic balance shows the prevalence of net heterotrophic community production. The demonstration of an important effect of UVB radiation on NCP in surface waters presented here is of particular relevance in relation to the increased UVB radiation derived from the erosion of the stratospheric ozone layer. Our results encourage design future research to further our understanding of UVB effects on the metabolic balance of plankton communities.

Ecological and Evolutionary Effects of Stickleback on Community Structure

PubMed Central

Des Roches, Simone; Shurin, Jonathan B.; Schluter, Dolph; Harmon, Luke J.

2013-01-01

Species’ ecology and evolution can have strong effects on communities. Both may change concurrently when species colonize a new ecosystem. We know little, however, about the combined effects of ecological and evolutionary change on community structure. We simultaneously examined the effects of top-predator ecology and evolution on freshwater community parameters using recently evolved generalist and specialist ecotypes of three-spine stickleback (Gasterosteus aculeatus). We used a mesocosm experiment to directly examine the effects of ecological (fish presence and density) and evolutionary (phenotypic diversity and specialization) factors on community structure at lower trophic levels. We evaluated zooplankton biomass and composition, periphyton and phytoplankton chlorophyll-a concentration, and net primary production among treatments containing different densities and diversities of stickleback. Our results showed that both ecological and evolutionary differences in the top-predator affect different aspects of community structure and composition. Community structure, specifically the abundance of organisms at each trophic level, was affected by stickleback presence and density, whereas composition of zooplankton was influenced by stickleback diversity and specialization. Primary productivity, in terms of chlorophyll-a concentration and net primary production was affected by ecological but not evolutionary factors. Our results stress the importance of concurrently evaluating both changes in density and phenotypic diversity on the structure and composition of communities. PMID:23573203

A network-based approach to disturbance transmission through microbial interactions

PubMed Central

Hunt, Dana E.; Ward, Christopher S.

2015-01-01

Microbes numerically dominate aquatic ecosystems and play key roles in the biogeochemistry and the health of these environments. Due to their short generations times and high diversity, microbial communities are among the first responders to environmental changes, including natural and anthropogenic disturbances such as storms, pollutant releases, and upwelling. These disturbances affect members of the microbial communities both directly and indirectly through interactions with impacted community members. Thus, interactions can influence disturbance propagation through the microbial community by either expanding the range of organisms affected or buffering the influence of disturbance. For example, interactions may expand the number of disturbance-affected taxa by favoring a competitor or buffer the impacts of disturbance when a potentially disturbance-responsive clade’s growth is limited by an essential microbial partner. Here, we discuss the potential to use inferred ecological association networks to examine how disturbances propagate through microbial communities focusing on a case study of a coastal community’s response to a storm. This approach will offer greater insight into how disturbances can produce community-wide impacts on aquatic environments following transient changes in environmental parameters. PMID:26579091

The role of topographic structure and soil macrofauna presence at spoil heaps during spontaneous succession.

NASA Astrophysics Data System (ADS)

Walmsley, Alena; Vachová, Pavla; Vach, Marek

2016-04-01

This research was investigating whether topographic features, which determine soil nutrient and moisture distribution, in combination with soil fauna (wireworm and earthworm) presence, affect plant community composition at a spontaneously revegetated post mining area with an undulating surface. Two sites of different age with 3 types of topographic features were selected, soil moisture and nutrient content were measured, plant community composition and soil macrofauna community was sampled at each position. Wireworms were present at all positions and were most abundant at bottoms of waves at the younger site; their presence was correlated with several plant species, but the direction of the interaction isn't clear. Earthworms were only present at the older site and had highest abundance at flat sections. Earthworm presence affected the amount of nitrogen in soil - the most nitrogen content was at the site with highest earthworm density and was followed by higher diversity of plant community. The plant community composition was generally correlated with plant available nutrient content - especially P and N. We infer that topographic features affect nutrient and soil fauna distribution, which consequently influences plant community composition.

Spatial patterns in community response to aircraft noise associated with non-noise factors

NASA Astrophysics Data System (ADS)

Hall, F. L.; Taylor, S. M.; Birnie, S. E.

1980-08-01

Non-noise aspects of airport operations may affect individuals' responses to aircraft noise. Fear of crashes, other forms of pollution, and proximity to the flight path are three such non-noise aspects which have spatial patterns that are closely related to the pattern of noise contours around an airport. If these variables affect response to aircraft noise, they may therefore confound attempts to understand relationships between noise level and community response. Analyses based on data from 673 individuals around Toronto International Airport suggest that these factors do affect annoyance responses, but do not affect reported activity interference. Hence it may prove fruitful, in aggregate analyses of community response data, to control for these variables in order to better understand the noise-annoyance relationships.

Community Attachment and Satisfaction: The Role of a Community's Social Network Structure

ERIC Educational Resources Information Center

Crowe, Jessica

2010-01-01

This paper links the micro and macro levels of analysis by examining how different aspects of community sentiment are affected by one's personal ties to the community compared with the organizational network structure of the community. Using data collected from residents of six communities in Washington State, network analysis combined with…

Community shifts under climate change: mechanisms at multiple scales.

PubMed

Gornish, Elise S; Tylianakis, Jason M

2013-07-01

Processes that drive ecological dynamics differ across spatial scales. Therefore, the pathways through which plant communities and plant-insect relationships respond to changing environmental conditions are also expected to be scale-dependent. Furthermore, the processes that affect individual species or interactions at single sites may differ from those affecting communities across multiple sites. We reviewed and synthesized peer-reviewed literature to identify patterns in biotic or abiotic pathways underpinning changes in the composition and diversity of plant communities under three components of climate change (increasing temperature, CO2, and changes in precipitation) and how these differ across spatial scales. We also explored how these changes to plants affect plant-insect interactions. The relative frequency of biotic vs. abiotic pathways of climate effects at larger spatial scales often differ from those at smaller scales. Local-scale studies show variable responses to climate drivers, often driven by biotic factors. However, larger scale studies identify changes to species composition and/or reduced diversity as a result of abiotic factors. Differing pathways of climate effects can result from different responses of multiple species, habitat effects, and differing effects of invasions at local vs. regional to global scales. Plant community changes can affect higher trophic levels as a result of spatial or phenological mismatch, foliar quality changes, and plant abundance changes, though studies on plant-insect interactions at larger scales are rare. Climate-induced changes to plant communities will have considerable effects on community-scale trophic exchanges, which may differ from the responses of individual species or pairwise interactions.

Governance factors in the identification of global conservation priorities for mammals

PubMed Central

Eklund, Johanna; Arponen, Anni; Visconti, Piero; Cabeza, Mar

2011-01-01

Global conservation priorities have often been identified based on the combination of species richness and threat information. With the development of the field of systematic conservation planning, more attention has been given to conservation costs. This leads to prioritizing developing countries, where costs are generally low and biodiversity is high. But many of these countries have poor governance, which may result in ineffective conservation or in larger costs than initially expected. We explore how the consideration of governance affects the selection of global conservation priorities for the world's mammals in a complementarity-based conservation prioritization. We use data on Control of Corruption (Worldwide Governance Indicators project) as an indicator of governance effectiveness, and gross domestic product per capita as an indicator of cost. We show that, while core areas with high levels of endemism are always selected as important regardless of governance and cost values, there are clear regional differences in selected sites when biodiversity, cost or governance are taken into account separately. Overall, the analysis supports the concentration of conservation efforts in most of the regions generally considered of high priority, but stresses the need for different conservation approaches in different continents owing to spatial patterns of governance and economic development. PMID:21844045

Protonation linked equilibria and apparent affinity constants: the thermodynamic profile of the alpha-chymotrypsin-proflavin interaction.

PubMed

Bruylants, Gilles; Wintjens, René; Looze, Yvan; Redfield, Christina; Bartik, Kristin

2007-12-01

Protonation/deprotonation equilibria are frequently linked to binding processes involving proteins. The presence of these thermodynamically linked equilibria affects the observable thermodynamic parameters of the interaction (K(obs), DeltaH(obs)(0) ). In order to try and elucidate the energetic factors that govern these binding processes, a complete thermodynamic characterisation of each intrinsic equilibrium linked to the complexation event is needed and should furthermore be correlated to structural information. We present here a detailed study, using NMR and ITC, of the interaction between alpha-chymotrypsin and one of its competitive inhibitors, proflavin. By performing proflavin titrations of the enzyme, at different pH values, we were able to highlight by NMR the effect of the complexation of the inhibitor on the ionisable residues of the catalytic triad of the enzyme. Using ITC we determined the intrinsic thermodynamic parameters of the different equilibria linked to the binding process. The possible driving forces of the interaction between alpha-chymotrypsin and proflavin are discussed in the light of the experimental data and on the basis of a model of the complex. This study emphasises the complementarities between ITC and NMR for the study of binding processes involving protonation/deprotonation equilibria.

Risk ON/Risk OFF: Risk-Taking Varies with Subjectively Preferred and Disliked Music.

PubMed

Halko, Marja-Liisa; Kaustia, Markku

2015-01-01

In this paper we conduct a within-subjects experiment in which teenagers go over 256 gambles with real money gains and losses. For each risky gamble they choose whether to participate in it, or pass. Prior to this main experiment subjects identify specific songs belonging to their favorite musical genre, as well as songs representing a style they dislike. In the main experiment we vary the music playing in the background, so that each subject hears some of their favorite music, and some disliked music, alternating in blocks of 16 gambles. We find that favorite music increases risk-taking ('risk on'), and disliked music suppresses risk-taking ('risk off'), compared to a baseline of no music. Literature in psychology proposes several mechanisms by which mood affects risk-taking, but none of them fully explain the results in our setting. The results are, however, consistent with the economics notion of preference complementarity, extended to the domain of risk preference. The preference structure implied by our results is more complex than previously thought, yet realistic, and consistent with recent theoretical models. More generally, this mechanism offers a potential explanation to why risk-taking is known to change over time and across contexts.

Governance factors in the identification of global conservation priorities for mammals.

PubMed

Eklund, Johanna; Arponen, Anni; Visconti, Piero; Cabeza, Mar

2011-09-27

Global conservation priorities have often been identified based on the combination of species richness and threat information. With the development of the field of systematic conservation planning, more attention has been given to conservation costs. This leads to prioritizing developing countries, where costs are generally low and biodiversity is high. But many of these countries have poor governance, which may result in ineffective conservation or in larger costs than initially expected. We explore how the consideration of governance affects the selection of global conservation priorities for the world's mammals in a complementarity-based conservation prioritization. We use data on Control of Corruption (Worldwide Governance Indicators project) as an indicator of governance effectiveness, and gross domestic product per capita as an indicator of cost. We show that, while core areas with high levels of endemism are always selected as important regardless of governance and cost values, there are clear regional differences in selected sites when biodiversity, cost or governance are taken into account separately. Overall, the analysis supports the concentration of conservation efforts in most of the regions generally considered of high priority, but stresses the need for different conservation approaches in different continents owing to spatial patterns of governance and economic development.

Community College Image--By Hollywood

ERIC Educational Resources Information Center

Tucciarone, Krista M.

2007-01-01

This qualitative study analyzes how the most recent community college film, Evolution (2001) depicts and portrays the image of a community college as interpreted by attending community college students. Previous community college research suggests that college choice, enrollment, and funding may be affected by perceived image. Image is greatly…

SDU: A Semidefinite Programming-Based Underestimation Method for Stochastic Global Optimization in Protein Docking

DTIC Science & Technology

2007-04-01

optimization methodology we introduce. State-of-the-art protein - protein docking approaches start by identifying conformations with good surface /chemical com...side-chains on the interface ). The protein - protein docking literature (e.g., [8] and the references therein) is predominantly treating the docking...mations by various measures of surface complementarity which can be efficiently computed using fast Fourier correlation tech- niques (FFTs). However, when

Development of a Novel Method to Detect Prostate Cancer Circulating Tumor Cells (CTCs) Based on Epithelial-Mesenchymal Transition Biology

DTIC Science & Technology

2015-12-01

different incubation periods for the cell lines (1 hour and overnight). We found that room temperature incubation provided the optimal temperature ...properties, either directly (through modification of residues in the complementarity determining region (CDR)) or indirectly through allosteric effects ...showed that the reduction in antigen binding affinity is associated with handling the antibody (e.g. temperature , buffer, purification steps) rather

Brazilian-Argentine Relations in the 1980s: from Wary Rivalry toward Friendly Competition

DTIC Science & Technology

1985-03-01

viability of countertrade , inward vs. outward orientations, internal stability, regime compatibility, comparative "advantage, political status of neighbors... countertrade or clearing-house type reciprocal credit accounts deals are established on a regular basis. The range of complementarity may be broad, but each...Success of countertrade or reciprocal credit clearing house accounting, to ease the cash flow bind. 2. Redirection of trade flows and concession of mutual

The Solution of Linear Complementarity Problems on an Array Processor.

DTIC Science & Technology

1981-01-01

INITIALIZE T04E 4IASK COMON /1SCA/M1AA ITERAIIJ)NSp NIUvld ITEWAILUNSPNUJ4d RUMboaJNI Co6 C3MAON /ISCA/I GRIL )POINTSo Y LiRIUPOINTS CDMAION /SUaLMjAT...GRI1D# WIDTH GRIfl LOGICAL MASWI MASK MASK INTEGE" X GRIL )POINTSo Y GRIOPUINTS 14JTEGEM MAX ITERATIONS# NUMB ITERArIONS9 NIJMO ROPIS, NUMB COLS C LOCAL

Relating quantum discord with the quantum dense coding capacity

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

Wang, Xin; Qiu, Liang, E-mail: lqiu@cumt.edu.cn; Li, Song

2015-01-15

We establish the relations between quantum discord and the quantum dense coding capacity in (n + 1)-particle quantum states. A necessary condition for the vanishing discord monogamy score is given. We also find that the loss of quantum dense coding capacity due to decoherence is bounded below by the sum of quantum discord. When these results are restricted to three-particle quantum states, some complementarity relations are obtained.

Structural Analysis of HMGD-DNA Complexes Reveal Influence of Intercalation on Sequence Selectivity and DNA Bending

PubMed Central

Churchill, Mair E.A.; Klass, Janet; Zoetewey, David L.

2010-01-01

The ubiquitous eukaryotic High-Mobility-Group-Box (HMGB) chromosomal proteins promote many chromatin-mediated cellular activities through their non-sequence-specific binding and bending of DNA. Minor groove DNA binding by the HMG box results in substantial DNA bending toward the major groove owing to electrostatic interactions, shape complementarity and DNA intercalation that occurs at two sites. Here, the structures of the complexes formed with DNA by a partially DNA intercalation-deficient mutant of Drosophila melanogaster HMGD have been determined by X-ray crystallography at a resolution of 2.85 Å. The six proteins and fifty base pairs of DNA in the crystal structure revealed a variety of bound conformations. All of the proteins bound in the minor groove, bridging DNA molecules, presumably because these DNA regions are easily deformed. The loss of the primary site of DNA intercalation decreased overall DNA bending and shape complementarity. However, DNA bending at the secondary site of intercalation was retained and most protein-DNA contacts were preserved. The mode of binding resembles the HMGB1-boxA-cisplatin-DNA complex, which also lacks a primary intercalating residue. This study provides new insights into the binding mechanisms used by HMG boxes to recognize varied DNA structures and sequences as well as modulate DNA structure and DNA bending. PMID:20800069

Validity of black hole complementarity in the BTZ black hole

NASA Astrophysics Data System (ADS)

Gim, Yongwan; Kim, Wontae

2018-01-01

Based on the gedanken experiment for black hole complementarity in the Schwarzschild black hole, we calculate the energy required to duplicate information in the BTZ black hole under the assumption of absorbing boundary condition and its dual solution of the black string, respectively, in order to justify the validity of the no-cloning theorem in quantum mechanics. For the BTZ black hole, the required energy for the duplication of information can be made fairly small, whereas for the black string it exceeds the total mass of the black string, although they are related to each other under the dual transformation. So, the duplication of information might be possible in the BTZ black hole in contrast to the case of the black string, so that the no-cloning theorem could be violated for the former case. To save the duplication of information for the BTZ black hole, we perform an improved gedanken experiment by using the local thermodynamic quantities near the horizon rather than those defined at infinity, and show that the no-cloning theorem could be made valid even in the BTZ black hole. We also discuss how this local treatment for the no-cloning theorem can be applied to the black string as well as the Schwarzschild black hole innocuously.

A Generic Self-Assembly Process in Microcompartments and Synthetic Protein Nanotubes.

PubMed

Uddin, Ismail; Frank, Stefanie; Warren, Martin J; Pickersgill, Richard W

2018-05-01

Bacterial microcompartments enclose a biochemical pathway and reactive intermediate within a protein envelope formed by the shell proteins. Herein, the orientation of the propanediol-utilization (Pdu) microcompartment shell protein PduA in bacterial microcompartments and in synthetic nanotubes, and the orientation of PduB in synthetic nanotubes are revealed. When produced individually, PduA hexamers and PduB trimers, tessellate to form flat sheets in the crystal, or they can self-assemble to form synthetic protein nanotubes in solution. Modelling the orientation of PduA in the 20 nm nanotube so as to preserve the shape complementarity and key interactions seen in the crystal structure suggests that the concave surface of the PduA hexamer faces out. This orientation is confirmed experimentally in synthetic nanotubes and in the bacterial microcompartment produced in vivo. The PduB nanotubes described here have a larger diameter, 63 nm, with the concave surface of the trimer again facing out. The conserved concave surface out characteristic of these nano-structures reveals a generic assembly process that causes the interface between adjacent subunits to bend in a common direction that optimizes shape complementarity and minimizes steric clashes. This understanding underpins engineering strategies for the biotechnological application of protein nanotubes. © 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Density of bunched threading dislocations in epitaxial GaN layers as determined using X-ray diffraction

NASA Astrophysics Data System (ADS)

Barchuk, M.; Holý, V.; Rafaja, D.

2018-04-01

X-ray diffraction is one of the most popular experimental methods employed for determination of dislocation densities, as it can recognize both the strain fields and the local lattice rotations produced by dislocations. The main challenge of the quantitative analysis of the dislocation density is the formulation of a suitable microstructure model, which describes the dislocation arrangement and the effect of the interactions between the strain fields from neighboring dislocations reliably in order to be able to determine the dislocation densities precisely. The aim of this study is to prove the capability of X-ray diffraction and two computational methods, which are frequently used for quantification of the threading dislocation densities from X-ray diffraction measurements, in the special case of partially bunched threading dislocations. The first method is based on the analysis of the dislocation-controlled crystal mosaicity, and the other one on the analysis of diffuse X-ray scattering from threading dislocations. The complementarity of both methods is discussed. Furthermore, it is shown how the complementarity of these methods can be used to improve the results of the quantitative analysis of bunched and thus inhomogeneously distributed threading dislocations and to get a better insight into the dislocation arrangement.

Response-based selection of barley cultivars and legume species for complementarity: Root morphology and exudation in relation to nutrient source.

PubMed

Giles, Courtney D; Brown, Lawrie K; Adu, Michael O; Mezeli, Malika M; Sandral, Graeme A; Simpson, Richard J; Wendler, Renate; Shand, Charles A; Menezes-Blackburn, Daniel; Darch, Tegan; Stutter, Marc I; Lumsdon, David G; Zhang, Hao; Blackwell, Martin S A; Wearing, Catherine; Cooper, Patricia; Haygarth, Philip M; George, Timothy S

2017-02-01

Phosphorus (P) and nitrogen (N) use efficiency may be improved through increased biodiversity in agroecosystems. Phenotypic variation in plants' response to nutrient deficiency may influence positive complementarity in intercropping systems. A multicomponent screening approach was used to assess the influence of P supply and N source on the phenotypic plasticity of nutrient foraging traits in barley (H. vulgare L.) and legume species. Root morphology and exudation were determined in six plant nutrient treatments. A clear divergence in the response of barley and legumes to the nutrient treatments was observed. Root morphology varied most among legumes, whereas exudate citrate and phytase activity were most variable in barley. Changes in root morphology were minimized in plants provided with ammonium in comparison to nitrate but increased under P deficiency. Exudate phytase activity and pH varied with legume species, whereas citrate efflux, specific root length, and root diameter lengths were more variable among barley cultivars. Three legume species and four barley cultivars were identified as the most responsive to P deficiency and the most contrasting of the cultivars and species tested. Phenotypic response to nutrient availability may be a promising approach for the selection of plant combinations for minimal input cropping systems. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Why Have Multiple Plastic Responses? Interactions between Color Change and Heat Avoidance Behavior in Battus philenor Larvae.

PubMed

Nielsen, Matthew E; Papaj, Daniel R

2017-06-01

Having multiple plastic responses to a change in the environment, such as increased temperature, can be adaptive for two major reasons: synergy (the plastic responses perform better when expressed simultaneously) or complementarity (each plastic response provides a greater net benefit in a different environmental context). We investigated these hypotheses for two forms of temperature-induced plasticity of Battus philenor caterpillars in southern Arizona populations: color change (from black to red at high temperatures) and heat avoidance behavior (movement from host to elevated refuges at high host temperatures). Field assays using aluminum models showed that the cooling effect of the red color is greatly reduced in a refuge position relative to that on a host. Field assays with live caterpillars demonstrated that refuge seeking is much more important for survival under hot conditions than coloration; however, in those assays, red coloration reduced the need to seek refuges. Our results support the complementarity hypothesis: refuge seeking facilitates survival during daily temperature peaks, while color change reduces the need to leave the host over longer warm periods. We propose that combinations of rapid but costly short-term behavioral responses and slow but efficient long-term morphological responses may be common when coping with temperature change.

Light-scattering studies of protein solutions: role of hydration in weak protein-protein interactions.

PubMed

Paliwal, A; Asthagiri, D; Abras, D; Lenhoff, A M; Paulaitis, M E

2005-09-01

We model the hydration contribution to short-range electrostatic/dispersion protein interactions embodied in the osmotic second virial coefficient, B(2), by adopting a quasi-chemical description in which water molecules associated with the protein are identified through explicit molecular dynamics simulations. These water molecules reduce the surface complementarity of highly favorable short-range interactions, and therefore can play an important role in mediating protein-protein interactions. Here we examine this quasi-chemical view of hydration by predicting the interaction part of B(2) and comparing our results with those derived from light-scattering measurements of B(2) for staphylococcal nuclease, lysozyme, and chymotrypsinogen at 25 degrees C as a function of solution pH and ionic strength. We find that short-range protein interactions are influenced by water molecules strongly associated with a relatively small fraction of the protein surface. However, the effect of these strongly associated water molecules on the surface complementarity of short-range protein interactions is significant, and must be taken into account for an accurate description of B(2). We also observe remarkably similar hydration behavior for these proteins despite substantial differences in their three-dimensional structures and spatial charge distributions, suggesting a general characterization of protein hydration.

Levels of reconstruction as complementarity in mixed methods research: a social theory-based conceptual framework for integrating qualitative and quantitative research.

PubMed

Carroll, Linda J; Rothe, J Peter

2010-09-01

Like other areas of health research, there has been increasing use of qualitative methods to study public health problems such as injuries and injury prevention. Likewise, the integration of qualitative and quantitative research (mixed-methods) is beginning to assume a more prominent role in public health studies. Likewise, using mixed-methods has great potential for gaining a broad and comprehensive understanding of injuries and their prevention. However, qualitative and quantitative research methods are based on two inherently different paradigms, and their integration requires a conceptual framework that permits the unity of these two methods. We present a theory-driven framework for viewing qualitative and quantitative research, which enables us to integrate them in a conceptually sound and useful manner. This framework has its foundation within the philosophical concept of complementarity, as espoused in the physical and social sciences, and draws on Bergson's metaphysical work on the 'ways of knowing'. Through understanding how data are constructed and reconstructed, and the different levels of meaning that can be ascribed to qualitative and quantitative findings, we can use a mixed-methods approach to gain a conceptually sound, holistic knowledge about injury phenomena that will enhance our development of relevant and successful interventions.