WorldWideScience

Sample records for bottom-up modeling approach

  1. Bottom-up modeling of oil production: A review of approaches

    International Nuclear Information System (INIS)

    Jakobsson, Kristofer; Söderbergh, Bengt; Snowden, Simon; Aleklett, Kjell

    2014-01-01

    Bottom-up models of oil production are continuously being used to guide investments and policymaking. Compared to simpler top-down models, bottom-up models have a number of advantages due to their modularity, flexibility and concreteness. The purposes of this paper is to identify the crucial modeling challenges, compare the different ways in which nine existing models handle them, assess the appropriateness of these models, and point to possibilities of further development. The conclusions are that the high level of detail in bottom-up models is of questionable value for predictive accuracy, but of great value for identifying areas of uncertainty and new research questions. There is a potential for improved qualitative insights through systematic sensitivity analysis. This potential is at present largely unrealized. - Highlights: • Bottom-up models are influential in the study of the oil production supply chain. • Nine existing bottom-up models are reviewed. • The high level of detail is of questionable value for predictive accuracy. • There is a potential for more systematic sensitivity analysis

  2. Bottom-up modeling approach for the quantitative estimation of parameters in pathogen-host interactions

    Directory of Open Access Journals (Sweden)

    Teresa eLehnert

    2015-06-01

    Full Text Available Opportunistic fungal pathogens can cause bloodstream infection and severe sepsis upon entering the blood stream of the host. The early immune response in human blood comprises the elimination of pathogens by antimicrobial peptides and innate immune cells, such as neutrophils or monocytes. Mathematical modeling is a predictive method to examine these complex processes and to quantify the dynamics of pathogen-host interactions. Since model parameters are often not directly accessible from experiment, their estimation is required by calibrating model predictions with experimental data. Depending on the complexity of the mathematical model, parameter estimation can be associated with excessively high computational costs in terms of run time and memory. We apply a strategy for reliable parameter estimation where different modeling approaches with increasing complexity are used that build on one another. This bottom-up modeling approach is applied to an experimental human whole-blood infection assay for Candida albicans. Aiming for the quantification of the relative impact of different routes of the immune response against this human-pathogenic fungus, we start from a non-spatial state-based model (SBM, because this level of model complexity allows estimating textit{a priori} unknown transition rates between various system states by the global optimization method simulated annealing. Building on the non-spatial SBM, an agent-based model (ABM is implemented that incorporates the migration of interacting cells in three-dimensional space. The ABM takes advantage of estimated parameters from the non-spatial SBM, leading to a decreased dimensionality of the parameter space. This space can be scanned using a local optimization approach, i.e. least-squares error estimation based on an adaptive regular grid search, to predict cell migration parameters that are not accessible in experiment.

  3. A bottom-up approach of stochastic demand allocation in water quality modelling

    NARCIS (Netherlands)

    Blokker, E.J.M.; Vreeburg, J.H.G.; Beverloo, H.; Klein Arfman, M.; Van Dijk, J.C.

    2010-01-01

    An “all pipes” hydraulic model of a DMA-sized drinking water distribution system was onstructed with two types of demand allocations. One is constructed with the conventional op-down approach, i.e. a demand multiplier pattern from the booster station is llocated to all demand nodes with a correction

  4. A bottom-up approach of stochastic demand allocation in water quality modelling

    NARCIS (Netherlands)

    Blokker, E.J.M.; Vreeburg, J.H.G.; Beverloo, H.; Klein Arfman, M.; Van Dijk, J.C.

    2010-01-01

    An “all pipes” hydraulic model of a drinking water distribution system was constructed with two types of demand allocations. One is constructed with the conventional top-down approach, i.e. a demand multiplier pattern from the booster station is allocated to all demand nodes with a correction factor

  5. D-Branes at Singularities A Bottom-Up Approach to the String Embedding of the Standard Model

    CERN Document Server

    Aldazabal, G.; Quevedo, F.; Uranga, A.M.

    2000-01-01

    We propose a bottom-up approach to the building of particle physics models from string theory. Our building blocks are Type II D-branes which we combine appropriately to reproduce desirable features of a particle theory model: 1) Chirality ; 2) Standard Model group ; 3) N=1 or N=0 supersymmetry ; 4) Three quark-lepton generations. We start such a program by studying configurations of D=10, Type IIB D3-branes located at singularities. We study in detail the case of Z_N, N=1,0 supersymmetric orbifold singularities leading to the SM group or some left-right symmetricextension. In general, tadpole cancellation conditions require the presence of additional branes, e.g. D7-branes. For the N=1 supersymmetric case the unique twist leading to three quark-lepton generations is Z_3, predicting $\\sin^2\\theta_W=3/14=0.21$. The models obtained are the simplest semirealistic string models ever built. In the non-supersymmetric case there is a three-generation model for each Z_N, N>4, but the Weinberg angle is in general too ...

  6. A Bottom-Up Approach to SUSY Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Claus; /SLAC

    2009-08-03

    This paper proposes a new way to perform event generation and analysis in searches for new physics at the LHC. An abstract notation is used to describe the new particles on a level which better corresponds to detector resolution of LHC experiments. In this way the SUSY discovery space can be decomposed into a small number of eigenmodes each with only a few parameters, which allows to investigate the SUSY parameter space in a model-independent way. By focusing on the experimental observables for each process investigated the Bottom-Up Approach allows to systematically study the boarders of the experimental efficiencies and thus to extend the sensitivity for new physics.

  7. A Bottom-Up Approach to SUSY Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Claus; /SLAC

    2011-11-11

    This paper proposes a new way to do event generation and analysis in searches for new physics at the LHC. An abstract notation is used to describe the new particles on a level which better corresponds to detector resolution of LHC experiments. In this way the SUSY discovery space can be decomposed into a small number of eigenmodes each with only a few parameters, which allows to investigate the SUSY parameter space in a model-independent way. By focusing on the experimental observables for each process investigated the Bottom-Up Approach allows to systematically study the boarders of the experimental efficiencies and thus to extend the sensitivity for new physics.

  8. Electroweak symmetry breaking the bottom-up approach

    CERN Document Server

    Kilian, Wolfgang

    2003-01-01

    The systematic bottom-up approach provides the appropriate framework for interpreting measurements that will be performed to better understand the physics of mass generation in the universe. No knowledge of quantum field theory is required other than familiarity with effective Lagrangians and Feynmann diagrams.

  9. The synthesis of bottom-up and top-down approaches to climate policy modeling: Electric power technology detail in a social accounting framework

    International Nuclear Information System (INIS)

    Sue Wing, Ian

    2008-01-01

    ''Hybrid'' climate policy simulations have sought to bridge the gap between ''bottom-up'' engineering and ''top-down'' macroeconomic models by integrating the former's energy technology detail into the latter's macroeconomic framework. Construction of hybrid models is complicated by the need to numerically calibrate them to multiple, incommensurate sources of economic and engineering data. I develop a solution to this problem following Howitt's [Howitt, R.E., 1995. Positive Mathematical Programming, American Journal of Agricultural Economics 77: 329-342] positive mathematical programming approach. Using data for the U.S., I illustrate how the inputs to the electricity sector in a social accounting matrix may be allocated among discrete types of generation so as to be consistent with both technologies' input shares from engineering cost estimates, and the zero profit and market clearance conditions of the sector's macroeconomic production structure. (author)

  10. Tailoring a cognitive behavioural model for unexplained physical symptoms to patient's perspective: a bottom-up approach.

    NARCIS (Netherlands)

    Zonneveld, L.N.; Duivenvoorden, H.J.; Passchier, J.; van 't Spijker, A

    2010-01-01

    The prevalence of unexplained physical symptoms (UPS) in primary care is at least 33%. Cognitive behavioural therapy has shown to be effective. Within cognitive behavioural therapy, three models can be distinguished: reattribution model, coping model and consequences model. The consequences model,

  11. Tailoring a cognitive behavioural model for unexplained physical symptoms to patient's perspective: A bottom-up approach

    NARCIS (Netherlands)

    L.N.L. Zonneveld (Lyonne); H.J. Duivenvoorden (Hugo); J. Passchier (Jan); A. van 't Spijker (Adriaan)

    2010-01-01

    textabstractThe prevalence of unexplained physical symptoms (UPS) in primary care is at least 33%. Cognitive behavioural therapy has shown to be effective. Within cognitive behavioural therapy, three models can be distinguished: reattribution model, coping model and consequences model. The

  12. A Vulnerability-Based, Bottom-up Assessment of Future Riverine Flood Risk Using a Modified Peaks-Over-Threshold Approach and a Physically Based Hydrologic Model

    Science.gov (United States)

    Knighton, James; Steinschneider, Scott; Walter, M. Todd

    2017-12-01

    There is a chronic disconnection among purely probabilistic flood frequency analysis of flood hazards, flood risks, and hydrological flood mechanisms, which hamper our ability to assess future flood impacts. We present a vulnerability-based approach to estimating riverine flood risk that accommodates a more direct linkage between decision-relevant metrics of risk and the dominant mechanisms that cause riverine flooding. We adapt the conventional peaks-over-threshold (POT) framework to be used with extreme precipitation from different climate processes and rainfall-runoff-based model output. We quantify the probability that at least one adverse hydrologic threshold, potentially defined by stakeholders, will be exceeded within the next N years. This approach allows us to consider flood risk as the summation of risk from separate atmospheric mechanisms, and supports a more direct mapping between hazards and societal outcomes. We perform this analysis within a bottom-up framework to consider the relevance and consequences of information, with varying levels of credibility, on changes to atmospheric patterns driving extreme precipitation events. We demonstrate our proposed approach using a case study for Fall Creek in Ithaca, NY, USA, where we estimate the risk of stakeholder-defined flood metrics from three dominant mechanisms: summer convection, tropical cyclones, and spring rain and snowmelt. Using downscaled climate projections, we determine how flood risk associated with a subset of mechanisms may change in the future, and the resultant shift to annual flood risk. The flood risk approach we propose can provide powerful new insights into future flood threats.

  13. Bottom-up approach for the reaction of xenobiotics and their metabolites with model substances for natural organic matter by electrochemistry-mass spectrometry (EC-MS).

    Science.gov (United States)

    Chen, Lei; Hofmann, Diana; Klumpp, Erwin; Xiang, Xinyi; Chen, Yingxu; Küppers, Stephan

    2012-11-01

    Risk assessment of xenobiotics requires a comprehensive understanding of their transformation in the environment. As most of the transformation processes usually involve a redox reaction or a hydrolysis as the first steps of the transformation, we applied an approach that uses an electrochemical cell to investigate model "redox" reactions in aqueous solutions for environmental processes. We investigated the degradation of a variety of xenobiotics from polar to nonpolar and analyzed their degradation products by on-line coupling of electrochemistry with mass spectrometry (EC-MS). Furthermore, we evaluated possible binding reactions with regard to the generation of non-extractable residues with some model substances (catechol, phthalic acid, γ-L-Glutamyl-L-cysteinyl-glycine (GSH) and L-histidine) deduced from a natural organic matter (NOM) structure model and identified possible binding-sites. Whereas typically investigations in soil/water-systems have been applied, we used to our knowledge for the first time a bottom-up approach, starting from the chemicals of interest and different model substances for natural organic matter to evaluate chemical binding mechanisms (or processes) in the EC-MS under redox conditions. Under oxidative conditions, bindings of the xenobiotics with catechol, GSH and histidine were found, but no reactions with the model compound phthalic acid were observed. In general, no chemical binding has yet been found under reductive conditions. In some cases (i.e. benzo[a]anthracene) the oxidation product only underwent a binding reaction, whereas the xenobiotic itself did not undergo any reactions. EC-MS is a promising fast and simple screening method to investigate the environmental behavior of xenobiotics and to evaluate the potential risks of newly synthesized substances. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Hydrodynamic cavitation: a bottom-up approach to liquid aeration

    NARCIS (Netherlands)

    Raut, J.S.; Stoyanov, S.D.; Duggal, C.; Pelan, E.G.; Arnaudov, L.N.; Naik, V.M.

    2012-01-01

    We report the use of hydrodynamic cavitation as a novel, bottom-up method for continuous creation of foams comprising of air microbubbles in aqueous systems containing surface active ingredients, like proteins or particles. The hydrodynamic cavitation was created using a converging-diverging nozzle.

  15. The synthesis of bottom-up and top-down approaches to climate policy modeling: Electric power technologies and the cost of limiting US CO2 emissions

    International Nuclear Information System (INIS)

    Wing, Ian Sue

    2006-01-01

    In the US, the bulk of CO 2 abatement induced by carbon taxes comes from electric power. This paper incorporates technology detail into the electricity sector of a computable general equilibrium model of the US economy to characterize electric power's technological margins of adjustment to carbon taxes and to elucidate their general equilibrium effects. Compared to the top-down production function representation of the electricity sector, the technology-rich hybrid specification produces less abatement at a higher welfare cost, suggesting that bottom-up models do not necessarily generate lower costs of abatement than top-down models. This result is shown to be sensitive to the elasticity with which technologies' generating capacities adjust to relative prices

  16. Bottom-up learning of hierarchical models in a class of deterministic POMDP environments

    Directory of Open Access Journals (Sweden)

    Itoh Hideaki

    2015-09-01

    Full Text Available The theory of partially observable Markov decision processes (POMDPs is a useful tool for developing various intelligent agents, and learning hierarchical POMDP models is one of the key approaches for building such agents when the environments of the agents are unknown and large. To learn hierarchical models, bottom-up learning methods in which learning takes place in a layer-by-layer manner from the lowest to the highest layer are already extensively used in some research fields such as hidden Markov models and neural networks. However, little attention has been paid to bottom-up approaches for learning POMDP models. In this paper, we present a novel bottom-up learning algorithm for hierarchical POMDP models and prove that, by using this algorithm, a perfect model (i.e., a model that can perfectly predict future observations can be learned at least in a class of deterministic POMDP environments

  17. Hierarchical time series bottom-up approach for forecast the export value in Central Java

    Science.gov (United States)

    Mahkya, D. A.; Ulama, B. S.; Suhartono

    2017-10-01

    The purpose of this study is Getting the best modeling and predicting the export value of Central Java using a Hierarchical Time Series. The export value is one variable injection in the economy of a country, meaning that if the export value of the country increases, the country’s economy will increase even more. Therefore, it is necessary appropriate modeling to predict the export value especially in Central Java. Export Value in Central Java are grouped into 21 commodities with each commodity has a different pattern. One approach that can be used time series is a hierarchical approach. Hierarchical Time Series is used Buttom-up. To Forecast the individual series at all levels using Autoregressive Integrated Moving Average (ARIMA), Radial Basis Function Neural Network (RBFNN), and Hybrid ARIMA-RBFNN. For the selection of the best models used Symmetric Mean Absolute Percentage Error (sMAPE). Results of the analysis showed that for the Export Value of Central Java, Bottom-up approach with Hybrid ARIMA-RBFNN modeling can be used for long-term predictions. As for the short and medium-term predictions, it can be used a bottom-up approach RBFNN modeling. Overall bottom-up approach with RBFNN modeling give the best result.

  18. Automated Urban Travel Interpretation: A Bottom-up Approach for Trajectory Segmentation

    Directory of Open Access Journals (Sweden)

    Rahul Deb Das

    2016-11-01

    Full Text Available Understanding travel behavior is critical for an effective urban planning as well as for enabling various context-aware service provisions to support mobility as a service (MaaS. Both applications rely on the sensor traces generated by travellers’ smartphones. These traces can be used to interpret travel modes, both for generating automated travel diaries as well as for real-time travel mode detection. Current approaches segment a trajectory by certain criteria, e.g., drop in speed. However, these criteria are heuristic, and, thus, existing approaches are subjective and involve significant vagueness and uncertainty in activity transitions in space and time. Also, segmentation approaches are not suited for real time interpretation of open-ended segments, and cannot cope with the frequent gaps in the location traces. In order to address all these challenges a novel, state based bottom-up approach is proposed. This approach assumes a fixed atomic segment of a homogeneous state, instead of an event-based segment, and a progressive iteration until a new state is found. The research investigates how an atomic state-based approach can be developed in such a way that can work in real time, near-real time and offline mode and in different environmental conditions with their varying quality of sensor traces. The results show the proposed bottom-up model outperforms the existing event-based segmentation models in terms of adaptivity, flexibility, accuracy and richness in information delivery pertinent to automated travel behavior interpretation.

  19. Automated Urban Travel Interpretation: A Bottom-up Approach for Trajectory Segmentation.

    Science.gov (United States)

    Das, Rahul Deb; Winter, Stephan

    2016-11-23

    Understanding travel behavior is critical for an effective urban planning as well as for enabling various context-aware service provisions to support mobility as a service (MaaS). Both applications rely on the sensor traces generated by travellers' smartphones. These traces can be used to interpret travel modes, both for generating automated travel diaries as well as for real-time travel mode detection. Current approaches segment a trajectory by certain criteria, e.g., drop in speed. However, these criteria are heuristic, and, thus, existing approaches are subjective and involve significant vagueness and uncertainty in activity transitions in space and time. Also, segmentation approaches are not suited for real time interpretation of open-ended segments, and cannot cope with the frequent gaps in the location traces. In order to address all these challenges a novel, state based bottom-up approach is proposed. This approach assumes a fixed atomic segment of a homogeneous state, instead of an event-based segment, and a progressive iteration until a new state is found. The research investigates how an atomic state-based approach can be developed in such a way that can work in real time, near-real time and offline mode and in different environmental conditions with their varying quality of sensor traces. The results show the proposed bottom-up model outperforms the existing event-based segmentation models in terms of adaptivity, flexibility, accuracy and richness in information delivery pertinent to automated travel behavior interpretation.

  20. A bottom-up approach to MEDLINE indexing recommendations

    DEFF Research Database (Denmark)

    Jimeno-Yepes, Antonio; Wilkowski, Bartlomiej; Mork, James/G

    2011-01-01

    in which the abstract is searched for indicators for a specific MeSH recommendation in a two-step process. Supervised machine learning combined with triage rules improves sensitivity of recommendations while keeping the number of recommended terms relatively small. Improvement in recommendations observed...... in this work warrants further exploration of this approach to MTI recommendations on a larger set of MeSH headings....

  1. Understanding latent structures of clinical information logistics: A bottom-up approach for model building and validating the workflow composite score.

    Science.gov (United States)

    Esdar, Moritz; Hübner, Ursula; Liebe, Jan-David; Hüsers, Jens; Thye, Johannes

    2017-01-01

    Clinical information logistics is a construct that aims to describe and explain various phenomena of information provision to drive clinical processes. It can be measured by the workflow composite score, an aggregated indicator of the degree of IT support in clinical processes. This study primarily aimed to investigate the yet unknown empirical patterns constituting this construct. The second goal was to derive a data-driven weighting scheme for the constituents of the workflow composite score and to contrast this scheme with a literature based, top-down procedure. This approach should finally test the validity and robustness of the workflow composite score. Based on secondary data from 183 German hospitals, a tiered factor analytic approach (confirmatory and subsequent exploratory factor analysis) was pursued. A weighting scheme, which was based on factor loadings obtained in the analyses, was put into practice. We were able to identify five statistically significant factors of clinical information logistics that accounted for 63% of the overall variance. These factors were "flow of data and information", "mobility", "clinical decision support and patient safety", "electronic patient record" and "integration and distribution". The system of weights derived from the factor loadings resulted in values for the workflow composite score that differed only slightly from the score values that had been previously published based on a top-down approach. Our findings give insight into the internal composition of clinical information logistics both in terms of factors and weights. They also allowed us to propose a coherent model of clinical information logistics from a technical perspective that joins empirical findings with theoretical knowledge. Despite the new scheme of weights applied to the calculation of the workflow composite score, the score behaved robustly, which is yet another hint of its validity and therefore its usefulness. Copyright © 2016 Elsevier Ireland

  2. Bottom-up approaches for preparing drug nanocrystals: formulations and factors affecting particle size.

    Science.gov (United States)

    Sinha, Biswadip; Müller, Rainer H; Möschwitzer, Jan P

    2013-08-30

    The solubility dependent bioavailability problem has become a major hurdle in drug development processes. Drug nanocrystals have been widely accepted by the pharmaceutical industry to improve the bioavailability of poorly water-soluble compounds. Top-down and bottom-up technologies are the two primary technical approaches of drug nanocrystal production. Though the top-down approach has been hugely successful on the commercial front, it has some inherent drawbacks that necessitate the emergence of alternate approaches. The bottom-up approach has not yet been established as a successful commercial technology. However, it has the potential to produce small size drug nanocrystals with less energy demanding processes. The bottom-up approach is commonly known as precipitation technique. It would be possible to stabilize particles at an early stage of precipitation and to generate drug nanocrystals. In the first part of this review article, we have discussed various bottom-up technologies that are currently in use. This has been followed by description and analysis of various process parameters that can affect the final particle size of the drug nanocrystals. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Dynamic formulation of a top-down and bottom-up merging energy policy model

    International Nuclear Information System (INIS)

    Frei, Christoph W.; Haldi, P.-A.; Sarlos, G.Gerard

    2003-01-01

    The impact of energy policy measures is not restricted to the energy system and should therefore be analysed within an economy-wide framework, while keeping the essential details of the energy sector. The aim of this paper is to present new developments in the field of the consistent evaluation of indicators for the sustainability assessment of energy policy measures. Starting from the static concept of Boehringer (Energy Econ. 20 (1998) 233), this paper shows how the complementarity format can be used in computable general equilibrium (CGE) modelling for a dynamic formulation of bottom-up and top-down approach merging models. While a hybrid approach increases the credibility of CGE models in energy policy analysis by replacing the energy sector generic functional forms with a bottom-up activity analysis based on specific technologies, the endogenous formulation of investment decisions makes an explicit description of evolving specific capital stocks and technology mixes possible. Both features are essential when assessing effects of policy measures that may be affected by structural change--which is typically the case in the long-term assessment of energy policy measures

  4. A bottom-up model to describe consumers’ preferences towards late season peaches

    Energy Technology Data Exchange (ETDEWEB)

    Groot, E.; Albisu, L.M.

    2015-07-01

    Peaches are consumed in Mediterranean countries since ancient times. Nowadays there are few areas in Europe that produce peaches with Protected Designation of Origin (PDO), and the Calanda area is one of them. The aim of this work is to describe consumers’ preferences towards late season PDO Calanda peaches in the city of Zaragoza, Spain, by a bottom-up model. The bottom-up model proves greater amount of information than top-down models. In this approach it is estimated one utility function per consumer. Thus, it is not necessary to make assumptions about preference distributions and correlations across respondents. It was observed that preference distributions were neither normal nor independently distributed. If those preferences were estimated by top-down models, conclusions would be biased. This paper also explores a new way to describe preferences through individual utility functions. Results show that the largest behavioural group gathered origin sensitive consumers. Their utility increased if the peaches were produced in the Calanda area and, especially, when peaches had the PDO Calanda brand. In sequence, the second most valuable attribute for consumers was the price. Peach size and packaging were not so important on purchase choice decision. Nevertheless, it is advisable to avoid trading smallest size peaches (weighting around 160 g/fruit). Traders also have to be careful by using active packaging. It was found that a group of consumers disliked this kind of product, probably, because they perceived it as less natural. (Author)

  5. A bottom-up model to describe consumers’ preferences towards late season peaches

    Directory of Open Access Journals (Sweden)

    Etiénne Groot

    2015-12-01

    Full Text Available Peaches are consumed in Mediterranean countries since ancient times. Nowadays there are few areas in Europe that produce peaches with Protected Designation of Origin (PDO, and the Calanda area is one of them. The aim of this work is to describe consumers’ preferences towards late season PDO Calanda peaches in the city of Zaragoza, Spain, by a bottom-up model. The bottom-up model proves greater amount of information than top-down models. In this approach it is estimated one utility function per consumer. Thus, it is not necessary to make assumptions about preference distributions and correlations across respondents. It was observed that preference distributions were neither normal nor independently distributed. If those preferences were estimated by top-down models, conclusions would be biased. This paper also explores a new way to describe preferences through individual utility functions. Results show that the largest behavioural group gathered origin sensitive consumers. Their utility increased if the peaches were produced in the Calanda area and, especially, when peaches had the PDO Calanda brand. In sequence, the second most valuable attribute for consumers was the price. Peach size and packaging were not so important on purchase choice decision. Nevertheless, it is advisable to avoid trading smallest size peaches (weighting around 160 g/fruit. Traders also have to be careful by using active packaging. It was found that a group of consumers disliked this kind of product, probably, because they perceived it as less natural.

  6. Bottom-up approach to sustainable urban development in Lebanon: The case of Zouk Mosbeh

    OpenAIRE

    El Asmar, Jean-Pierre; Ebohon, O. J.; Taki, A. H.

    2012-01-01

    In contrast with the “top-down” approach to development, the dominant methodology in Lebanon, Iemphasize rather the “bottom-up” approach where all stakeholders have equal opportunities to participate in policy formulation and implementation. The bottom-up or participatory approach to sustainable development has hardly been tested for urban development and management in Lebanon. This research concerns the sustainable rehabilitation of the built environment in the area of Zouk Mosbeh (ZM) in ...

  7. Rational design of modular circuits for gene transcription: A test of the bottom-up approach

    Directory of Open Access Journals (Sweden)

    Giordano Emanuele

    2010-11-01

    Full Text Available Abstract Background Most of synthetic circuits developed so far have been designed by an ad hoc approach, using a small number of components (i.e. LacI, TetR and a trial and error strategy. We are at the point where an increasing number of modular, inter-changeable and well-characterized components is needed to expand the construction of synthetic devices and to allow a rational approach to the design. Results We used interchangeable modular biological parts to create a set of novel synthetic devices for controlling gene transcription, and we developed a mathematical model of the modular circuits. Model parameters were identified by experimental measurements from a subset of modular combinations. The model revealed an unexpected feature of the lactose repressor system, i.e. a residual binding affinity for the operator site by induced lactose repressor molecules. Once this residual affinity was taken into account, the model properly reproduced the experimental data from the training set. The parameters identified in the training set allowed the prediction of the behavior of networks not included in the identification procedure. Conclusions This study provides new quantitative evidences that the use of independent and well-characterized biological parts and mathematical modeling, what is called a bottom-up approach to the construction of gene networks, can allow the design of new and different devices re-using the same modular parts.

  8. A Bottom-up Approach to Environmental Cost-Benefit Analysis

    DEFF Research Database (Denmark)

    Carolus, Johannes Friedrich; Hanley, Nick; Olsen, Søren Bøye

    to identifying and valuing relevant cost and benefit flows. This paper investigates the possible advantages, prerequisites and limitations of applying CBA in what may be considered an alternative, “bottom-up”. Instead of starting out with a pre-defined policy option, the suggested approach begins...... with the underlying environmental problem, and then assesses costs and benefits of various strategies and solutions suggested by local and directly affected stakeholders. For empirical case studies concerning two river catchments in Sweden and Latvia, the bottom-up CBA approach utilises local knowledge, assesses...... plans which are not only developed for local conditions but are also likely to be more acceptable to local society, and sheds additional light on possible distributional effects. By not only benefitting from, but also supporting participative environmental planning, bottom-up CBA is in line...

  9. People-centred health systems, a bottom-up approach: where theory meets empery.

    Science.gov (United States)

    Sturmberg, Joachim P; Njoroge, Alice

    2017-04-01

    Health systems are complex and constantly adapt to changing demands. These complex-adaptive characteristics are rarely considered in the current bureaucratic top-down approaches to health system reforms aimed to constrain demand and expenditure growth. The economic focus fails to address the needs of patients, providers and communities, and ultimately results in declining effectiveness and efficiency of the health care system as well as the health of the wider community. A needs-focused complex-adaptive health system can be represented by the 'healthcare vortex' model; how to build a needs-focused complex-adaptive health system is illustrated by Eastern Deanery AIDS Relief Program approaches in the poor neighbourhoods of Nairobi, Kenya. A small group of nurses and community health workers focused on the care of terminally ill HIV/AIDS patients. This work identified additional problems: tuberculosis (TB) was underdiagnosed and undertreated, a local TB-technician was trained to run a local lab, a courier services helped to reach all at need, collaboration with the Ministry of Health established local TB and HIV treatment programmes and philanthropists helped to supplement treatment with nutrition support. Maternal-to-child HIV-prevention and adolescent counselling services addressed additional needs. The 'theory of the healthcare vortex' indeed matches the 'empery of the real world experiences'. Locally developed and delivered adaptive, people-centred health systems, a bottom-up community and provider initiated approach, deliver highly effective and sustainable health care despite significant resource constraints. © 2016 John Wiley & Sons, Ltd.

  10. Comparison of bottom-up proteomic approaches for LC-MS analysis of complex proteomes.

    Science.gov (United States)

    Weston, Leigh A; Bauer, Kerry M; Hummon, Amanda B

    2013-09-21

    Discovery-based proteomic studies aim to answer important biological questions by identifying as many proteins as possible. In order to accomplish this lofty goal, an effort must be placed on determining an optimal workflow that maximizes protein identifications. In this study, we compare protein extraction, digestion and fractionation methods for bottom-up proteomics using a human colon cancer cell line as our model system. Four different buffers for protein extraction, two digestion approaches, as well as three sample fractionation methods were evaluated in order to determine an accessible workflow that gives maximal protein identifications. Samples comparing these workflows were analyzed via UPLC paired with tandem MS on a Q-Exactive mass spectrometer. Our goal is to determine an optimal workflow to enable users to maximize protein identifications. Our results show that an increased number of confident protein identifications are attained with a filter-aided digestion approach as compared to an in-solution digestion. Overall SDS-PAGE fractionation leads to higher numbers of identifications than SCX SpinTip and reverse phased cartridge platforms. The novel aspect of this work is the comparison of two readily available, offline platforms for fractionation in reference to a traditional technique, SDS-PAGE.

  11. A 'bottom-up' approach to aetiological research in autism spectrum disorders

    Directory of Open Access Journals (Sweden)

    Lisa Marie Unwin

    2013-09-01

    Full Text Available Autism Spectrum Disorders (ASD are currently diagnosed in the presence of impairments in social interaction and communication, and a restricted range of activities and interests. However, there is considerable variability in the behaviours of different individuals with an ASD diagnosis. The heterogeneity spans the entire range of IQ and language abilities, as well as other behavioural, communicative and social functions. While any psychiatric condition is likely to incorporate a degree of heterogeneity, the variability in the nature and severity of behaviours observed in ASD is thought to exceed that of other disorders. The current paper aims to provide a model for future research into ASD subgroups. In doing so, we examined whether two proposed risk factors – low birth weight (LBW, and in-utero exposure to selective serotonin reuptake inhibitors (SSRIs – are associated with greater behavioural homogeneity. Using data from the Western Australian Autism Biological Registry, this study found that LBW and maternal SSRI use during pregnancy were associated with greater sleep disturbances and a greater number of gastrointestinal complaints in children with ASD, respectively. The findings from this ‘proof of principle’ paper provide support for this 'bottom-up' approach as a feasible method for creating homogenous groups.

  12. Environmental Stress, Bottom-up Effects, and Community Dynamics: Integrating Molecular-Physiological and Ecological Approaches.

    Science.gov (United States)

    Menge, Bruce A; Olson, Annette M; Dahlhoff, Elizabeth P

    2002-08-01

    Environmental stress and nutrient/productivity models predict the responses of community structure along gradients of physical conditions and bottom-up effects. Although both models have succeeded in helping to understand variation in ecological communities, most tests have been qualitative. Until recently, two roadblocks to more quantitative tests in marine environments have been a lack of (1) inexpensive, field-deployable technology for quantifying (e.g.) temperature, light, salinity, chlorophyll, and productivity, and (2) methods of quantifying the sub-organismal mechanisms linking environmental conditions to their ecological expression. The advent of inexpensive remote-sensing technology, adoption of molecular techniques such as quantification of heat-shock proteins and RNA:DNA ratios, and the formation of interdisciplinary alliances between ecologists and physiologists has begun to overcome these roadblocks. An integrated eco-physiological approach focuses on the determinants of: distributional limits among microhabitat patches and along (local-scale) environmental gradients (e.g., zonation); among-site (mesoscale) differences in community pattern; and geographic (macroscale) differences in ecosystem structure. These approaches promise new insights into the physiological mechanisms underlying variation in processes such as species interactions, physical disturbance, survival and growth. Here, we review two classes of models for community dynamics, and present examples of ecological studies of these models in consumer-prey systems. We illustrate the power of new molecular tools to characterize the sub-organismal responses of some of the same consumers and prey to thermal stress and food concentration. Ecological and physiological evidence tends to be consistent with model predictions, supporting our argument that we are poised to make major advances in the mechanistic understanding of community dynamics along key environmental gradients.

  13. Coupled multi-physics simulation frameworks for reactor simulation: A bottom-up approach

    International Nuclear Information System (INIS)

    Tautges, Timothy J.; Caceres, Alvaro; Jain, Rajeev; Kim, Hong-Jun; Kraftcheck, Jason A.; Smith, Brandon M.

    2011-01-01

    A 'bottom-up' approach to multi-physics frameworks is described, where first common interfaces to simulation data are developed, then existing physics modules are adapted to communicate through those interfaces. Physics modules read and write data through those common interfaces, which also provide access to common simulation services like parallel IO, mesh partitioning, etc.. Multi-physics codes are assembled as a combination of physics modules, services, interface implementations, and driver code which coordinates calling these various pieces. Examples of various physics modules and services connected to this framework are given. (author)

  14. A bottom-up institutional approach to cooperative governance of risky commons

    Science.gov (United States)

    Vasconcelos, Vítor V.; Santos, Francisco C.; Pacheco, Jorge M.

    2013-09-01

    Avoiding the effects of climate change may be framed as a public goods dilemma, in which the risk of future losses is non-negligible, while realizing that the public good may be far in the future. The limited success of existing attempts to reach global cooperation has been also associated with a lack of sanctioning institutions and mechanisms to deal with those who do not contribute to the welfare of the planet or fail to abide by agreements. Here we investigate the emergence and impact of different types of sanctioning to deter non-cooperative behaviour in climate agreements. We show that a bottom-up approach, in which parties create local institutions that punish free-riders, promotes the emergence of widespread cooperation, mostly when risk perception is low, as it is at present. On the contrary, global institutions provide, at best, marginal improvements regarding overall cooperation. Our results clearly suggest that a polycentric approach involving multiple institutions is more effective than that associated with a single, global one, indicating that such a bottom-up, self-organization approach, set up at a local scale, provides a better ground on which to attempt a solution for such a complex and global dilemma.

  15. Importance of bottom-up approach in water management - sustainable development of catchment areas in Croatia

    Science.gov (United States)

    Pavic, M.; Cosic-Flajsig, G.; Petricec, M.; Blazevic, Z.

    2012-04-01

    Association for preservation of Croatian waters and sea SLAP is a non-governmental organization (NGO) that gathers more than 150 scientist, hydrologist and civil engineers. SLAP has been established in 2006 and since then had organized many conferences and participated in projects dealing with water management. We have started our work developing plans to secure water supply to the 22 (21) villages in the rural parts of Dubrovnik (Pozega) area and trough the years we have accumulated knowledge and experience in dealing with stakeholders in hydrology and water management. Within this paper we will present importance of bottom-up approach to the stakeholders in water management in Croatia on two case studies: (1) Management of River Trebizat catchment area - irrigation of the Imotsko-Bekijsko rural parts; (2) Development of multipurpose water reservoirs at the River Orljava catchment area. Both projects were designed in the mid and late 1980's but due to the war were forgotten and on halt. River Trebizat meanders between Croatia and Bosnia and Herzegovina and acquires joint management by both countries. In 2010 and 2011 SLAP has organized conferences in both countries gathering all the relevant stakeholders from representatives of local and state governments, water management companies and development agencies to the scientist and interested NGO's. The conferences gave firm scientific background of the topic including presentation of all previous studies and measurements as well as model results but presented in manner appropriate to the stakeholders. The main result of the conference was contribution to the development of joint cross-border project sent to the EU Pre-Accession funds in December 2011 with the aim to strengthen capacities of both countries and prepare larger project dealing with management of the whole Trebizat catchment area to EU structural funds once Croatia enters EU in 2013. Similar approach was taken for the Orljava catchment in the northern

  16. Comparing top-down and bottom-up costing approaches for economic evaluation within social welfare.

    Science.gov (United States)

    Olsson, Tina M

    2011-10-01

    This study compares two approaches to the estimation of social welfare intervention costs: one "top-down" and the other "bottom-up" for a group of social welfare clients with severe problem behavior participating in a randomized trial. Intervention costs ranging over a two-year period were compared by intervention category (foster care placement, institutional placement, mentorship services, individual support services and structured support services), estimation method (price, micro costing, average cost) and treatment group (intervention, control). Analyses are based upon 2007 costs for 156 individuals receiving 404 interventions. Overall, both approaches were found to produce reliable estimates of intervention costs at the group level but not at the individual level. As choice of approach can greatly impact the estimate of mean difference, adjustment based on estimation approach should be incorporated into sensitivity analyses. Analysts must take care in assessing the purpose and perspective of the analysis when choosing a costing approach for use within economic evaluation.

  17. A bottom-up approach for the synthesis of highly ordered fullerene-intercalated graphene hybrids

    Directory of Open Access Journals (Sweden)

    Dimitrios eGournis

    2015-02-01

    Full Text Available Much of the research effort on graphene focuses on its use as a building block for the development of new hybrid nanostructures with well-defined dimensions and properties suitable for applications such as gas storage, heterogeneous catalysis, gas/liquid separations, nanosensing and biomedicine. Towards this aim, here we describe a new bottom-up approach, which combines self-assembly with the Langmuir Schaefer deposition technique to synthesize graphene-based layered hybrid materials hosting fullerene molecules within the interlayer space. Our film preparation consists in a bottom-up layer-by-layer process that proceeds via the formation of a hybrid organo-graphene oxide Langmuir film. The structure and composition of these hybrid fullerene-containing thin multilayers deposited on hydrophobic substrates were characterized by a combination of X-ray diffraction, Raman and X-ray photoelectron spectroscopies, atomic force microscopy and conductivity measurements. The latter revealed that the presence of C60 within the interlayer spacing leads to an increase in electrical conductivity of the hybrid material as compared to the organo-graphene matrix alone.

  18. A bottom up approach for engineering catchments through sustainable runoff management

    Science.gov (United States)

    Wilkinson, M.; Quinn, P. F.; Jonczyk, J.; Burke, S.

    2010-12-01

    There is no doubt that our catchments are under great stress. There have been many accounts around the world of severe flood events and water quality issues within channels. As a result of these, ecological habitats in rivers are also under pressure. Within the United Kingdom, all these issues have been identified as key target areas for policy. Traditionally this has been managed by a policy driven top down approach which is usually ineffective. A one ‘size fits all’ attitude often does not work. This paper presents a case study in northern England whereby a bottom up approach is applied to multipurpose managing of catchments at the source (in the order of 1-10km2). This includes simultaneous tackling of water quality, flooding and ecological issues by creating sustainable runoff management solutions such as storage ponds, wetlands, beaver dams and willow riparian features. In order to identify the prevailing issues in a specific catchment, full and transparent stakeholder engagement is essential, with everybody who has a vested interest in the catchment being involved from the beginning. These problems can then be dealt with through the use of a novel catchment management toolkit, which is transferable to similar scale catchments. However, evidence collected on the ground also allows for upscaling of the toolkit. The process gathers the scientific evidence about the effectiveness of existing or new measures, which can really change the catchment functions. Still, we need to get better at communicating the science to policy makers and policy therefore must facilitate a bottom up approach to land and water management. We show a test site for this approach in the Belford burn catchment (6km2), northern England. This catchment has problems with flooding and water quality. Increased sediment loads are affecting the nearby estuary which is an important ecological zone and numerous floods have affected the local village. A catchment engineering toolkit has been

  19. A bottom-up approach to urban metabolism: the perspective of BRIDGE

    Science.gov (United States)

    Chrysoulakis, N.; Borrego, C.; San Josè, R.; Grimmond, S. B.; Jones, M. B.; Magliulo, V.; Klostermann, J.; Santamouris, M.

    2011-12-01

    Urban metabolism considers a city as a system and usually distinguishes between energy and material flows as its components. "Metabolic" studies are usually top-down approaches that assess the inputs and outputs of food, water, energy, and pollutants from a city, or that compare the changing metabolic process of several cities. In contrast, bottom-up approaches are based on quantitative estimates of urban metabolism components at local to regional scales. Such approaches consider the urban metabolism as the 3D exchange and transformation of energy and matter between a city and its environment. The city is considered as a system and the physical flows between this system and its environment are quantitatively estimated. The transformation of landscapes from primarily agricultural and forest uses to urbanized landscapes can greatly modify energy and material exchanges and it is, therefore, an important aspect of an urban area. Here we focus on the exchanges and transformation of energy, water, carbon and pollutants. Recent advances in bio-physical sciences have led to new methods and models to estimate local scale energy, water, carbon and pollutant fluxes. However, there is often poor communication of new knowledge and its implications to end-users, such as planners, architects and engineers. The FP7 Project BRIDGE (SustainaBle uRban plannIng Decision support accountinG for urban mEtabolism) aims at bridging this gap and at illustrating the advantages of considering environmental issues in urban planning. BRIDGE does not perform a complete life cycle analysis or calculate whole system urban metabolism, but rather focuses on specific metabolism components (energy, water, carbon and pollutants). Its main goal is the development of a Decision Suport System (DSS) with the potential to select planning actions which better fit the goal of changing the metabolism of urban systems towards sustainability. BRIDGE evaluates how planning alternatives can modify the physical

  20. Bottom-Up Abstract Modelling of Optical Networks-on-Chip: From Physical to Architectural Layer

    Directory of Open Access Journals (Sweden)

    Alberto Parini

    2012-01-01

    Full Text Available This work presents a bottom-up abstraction procedure based on the design-flow FDTD + SystemC suitable for the modelling of optical Networks-on-Chip. In this procedure, a complex network is decomposed into elementary switching elements whose input-output behavior is described by means of scattering parameters models. The parameters of each elementary block are then determined through 2D-FDTD simulation, and the resulting analytical models are exported within functional blocks in SystemC environment. The inherent modularity and scalability of the S-matrix formalism are preserved inside SystemC, thus allowing the incremental composition and successive characterization of complex topologies typically out of reach for full-vectorial electromagnetic simulators. The consistency of the outlined approach is verified, in the first instance, by performing a SystemC analysis of a four-input, four-output ports switch and making a comparison with the results of 2D-FDTD simulations of the same device. Finally, a further complex network encompassing 160 microrings is investigated, the losses over each routing path are calculated, and the minimum amount of power needed to guarantee an assigned BER is determined. This work is a basic step in the direction of an automatic technology-aware network-level simulation framework capable of assembling complex optical switching fabrics, while at the same time assessing the practical feasibility and effectiveness at the physical/technological level.

  1. Second Language Listening Instruction: Comparing a Strategies-Based Approach with an Interactive, Strategies/Bottom-Up Skills Approach

    Science.gov (United States)

    Yeldham, Michael

    2016-01-01

    This quasi-experimental study compared a strategies approach to second language listening instruction with an interactive approach, one combining a roughly equal balance of strategies and bottom-up skills. The participants were lower-intermediate-level Taiwanese university EFL learners, who were taught for 22 hours over one and a half semesters.…

  2. Estimating storage dynamics by combining top-down and bottom-up approaches

    Science.gov (United States)

    Barthold, F. K.; Kraft, P.; Vache, K. B.; Frede, H. G.; Breuer, L.

    2010-12-01

    The identification of storage dynamics in remote areas is limited by data scarcity. Both top-down and bottom up approaches to identify dominant hydrological processes often fail under these circumstances. In this study, we are combining both approaches in order to test several hypotheses concerning storage dynamics. The upper Xilin catchment, Inner Mongolia, China, is a primary example for such a situation. In the last few years numerous measurement campaigns were carried out in this area to investigate the impact of increasing land use intensity on different ecosystem functions. These included the measurement of water quantity and quality in the stream, rain and groundwaters, soil physical data as well as vegetation data. Despite the apparent abundance of these data, they are not representative for the seasonal and interannual variability of the hydrological processes. Existing time series are short and discontinuous, and catchment characteristics are measured with a low spatial density. In a first step, environmental tracer data were used to calculate the contribution of different sources to the stream water. The newly obtained information of this end member mixing analyzes (EMMA) is used to guide conceptual model development in a “soft data” manner. In addition, it will be applied in a process-based rejectionist framework as a posteriori model calibration criteria. The information about geographic source contributions to stream guides the development of a physically based reservoir model using the Catchment Modeling Framework (CMF). Such an approach is able to support hypothesis testing to evaluate the newly acquired information and to gain more insight into the processes of the catchment. The hypotheses are: -Sand dune groundwater aquifer is the main source for the river during wet years, while deep groundwater aquifers are the main source in dry years -The effective catchment area is much smaller than the topographic, -The effective catchment area varies

  3. Collective Inclusioning: A Grounded Theory of a Bottom-Up Approach to Innovation and Leading

    Directory of Open Access Journals (Sweden)

    Michal Lysek

    2016-06-01

    Full Text Available This paper is a grounded theory study of how leaders (e.g., entrepreneurs, managers, etc. engage people in challenging undertakings (e.g., innovation that require everyone’s commitment to such a degree that they would have to go beyond what could be reasonably expected in order to succeed. Company leaders sometimes wonder why their employees no longer show the same responsibility towards their work, and why they are more concerned with internal politics than solving customer problems. It is because company leaders no longer apply collective inclusioning to the same extent as they did in the past. Collective inclusioning can be applied in four ways by convincing, afinitizing, goal congruencing, and engaging. It can lead to fostering strong units of people for taking on challenging undertakings. Collective inclusioning is a complementing theory to other strategic management and leading theories. It offers a new perspective on how to implement a bottom-up approach to innovation.

  4. Towards self-assembled hybrid artificial cells: novel bottom-up approaches to functional synthetic membranes.

    Science.gov (United States)

    Brea, Roberto J; Hardy, Michael D; Devaraj, Neal K

    2015-09-01

    There has been increasing interest in utilizing bottom-up approaches to develop synthetic cells. A popular methodology is the integration of functionalized synthetic membranes with biological systems, producing "hybrid" artificial cells. This Concept article covers recent advances and the current state-of-the-art of such hybrid systems. Specifically, we describe minimal supramolecular constructs that faithfully mimic the structure and/or function of living cells, often by controlling the assembly of highly ordered membrane architectures with defined functionality. These studies give us a deeper understanding of the nature of living systems, bring new insights into the origin of cellular life, and provide novel synthetic chassis for advancing synthetic biology. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Metabolic Network Discovery by Top-Down and Bottom-Up Approaches and Paths for Reconciliation

    International Nuclear Information System (INIS)

    Çakır, Tunahan; Khatibipour, Mohammad Jafar

    2014-01-01

    The primary focus in the network-centric analysis of cellular metabolism by systems biology approaches is to identify the active metabolic network for the condition of interest. Two major approaches are available for the discovery of the condition-specific metabolic networks. One approach starts from genome-scale metabolic networks, which cover all possible reactions known to occur in the related organism in a condition-independent manner, and applies methods such as the optimization-based Flux-Balance Analysis to elucidate the active network. The other approach starts from the condition-specific metabolome data, and processes the data with statistical or optimization-based methods to extract information content of the data such that the active network is inferred. These approaches, termed bottom-up and top-down, respectively, are currently employed independently. However, considering that both approaches have the same goal, they can both benefit from each other paving the way for the novel integrative analysis methods of metabolome data- and flux-analysis approaches in the post-genomic era. This study reviews the strengths of constraint-based analysis and network inference methods reported in the metabolic systems biology field; then elaborates on the potential paths to reconcile the two approaches to shed better light on how the metabolism functions.

  6. Representing energy technologies in top-down economic models using bottom-up information

    Energy Technology Data Exchange (ETDEWEB)

    McFarland, J.R. [M.I.T., Cambridge, MA (United States). Technology and Policy Program; Reilly, J.M. [M.I.T., Cambridge, MA (United States). Joint Program on the Science and Policy of Global Change; Herzog, H.J. [M.I.T., Cambridge, MA (United States). Laboratory for Energy and the Environment

    2004-07-01

    The rate and magnitude of technological change is a critical component in estimating future anthropogenic carbon emissions. We present a methodology for modeling low-carbon emitting technologies within the MIT Emissions Prediction and Policy Analysis (EPPA) model, a computable general equilibrium (CGE) model of the world economy. The methodology translates bottom-up engineering information for two carbon capture and sequestration (CCS) technologies in the electric power sector into the EPPA model and discusses issues that arise in assuring an accurate representation and realistic market penetration. We find that coal-based technologies with sequestration penetrate, despite their higher cost today, because of projected rising natural gas prices. (author)

  7. Representing Farmer Irrigation Decisions in Northern India: Model Development from the Bottom Up.

    Science.gov (United States)

    O'Keeffe, J.; Buytaert, W.; Brozovic, N.; Mijic, A.

    2017-12-01

    The plains of northern India are among the most intensely populated and irrigated regions of the world. Sustaining water demand has been made possible by exploiting the vast and hugely productive aquifers underlying the Indo-Gangetic basin. However, an increasing demand from a growing population and highly variable socio-economic and environmental variables mean present resources may not be sustainable, resulting in water security becoming one of India's biggest challenges. Unless solutions which take into consideration the regions evolving anthropogenic and environmental conditions are found, the sustainability of India's water resources looks bleak. Understanding water user decisions and their potential outcome is important for development of suitable water resource management options. Computational models are commonly used to assist water use decision making, typically representing natural processes well. The inclusion of human decision making however, one of the dominant drivers of change, has lagged behind. Improved representation of irrigation water user behaviour within models provides more accurate, relevant information for irrigation management. This research conceptualizes and proceduralizes observed farmer irrigation practices, highlighting feedbacks between the environment and livelihood. It is developed using a bottom up approach, informed through field experience and stakeholder interaction in Uttar Pradesh, northern India. Real world insights are incorporated through collected information creating a realistic representation of field conditions, providing a useful tool for policy analysis and water management. The modelling framework is applied to four districts. Results suggest predicted future climate will have little direct impact on water resources, crop yields or farmer income. In addition, increased abstraction may be sustainable in some areas under carefully managed conditions. By simulating dynamic decision making, feedbacks and interactions

  8. A bottom-up approach to estimating cost elements of REDD+ pilot projects in Tanzania

    Directory of Open Access Journals (Sweden)

    Merger Eduard

    2012-08-01

    Full Text Available Abstract Background Several previous global REDD+ cost studies have been conducted, demonstrating that payments for maintaining forest carbon stocks have significant potential to be a cost-effective mechanism for climate change mitigation. These studies have mostly followed highly aggregated top-down approaches without estimating the full range of REDD+ costs elements, thus underestimating the actual costs of REDD+. Based on three REDD+ pilot projects in Tanzania, representing an area of 327,825 ha, this study explicitly adopts a bottom-up approach to data assessment. By estimating opportunity, implementation, transaction and institutional costs of REDD+ we develop a practical and replicable methodological framework to consistently assess REDD+ cost elements. Results Based on historical land use change patterns, current region-specific economic conditions and carbon stocks, project-specific opportunity costs ranged between US$ -7.8 and 28.8 tCOxxxx for deforestation and forest degradation drivers such as agriculture, fuel wood production, unsustainable timber extraction and pasture expansion. The mean opportunity costs for the three projects ranged between US$ 10.1 – 12.5 tCO2. Implementation costs comprised between 89% and 95% of total project costs (excluding opportunity costs ranging between US$ 4.5 - 12.2 tCO2 for a period of 30 years. Transaction costs for measurement, reporting, verification (MRV, and other carbon market related compliance costs comprised a minor share, between US$ 0.21 - 1.46 tCO2. Similarly, the institutional costs comprised around 1% of total REDD+ costs in a range of US$ 0.06 – 0.11 tCO2. Conclusions The use of bottom-up approaches to estimate REDD+ economics by considering regional variations in economic conditions and carbon stocks has been shown to be an appropriate approach to provide policy and decision-makers robust economic information on REDD+. The assessment of opportunity costs is a crucial first step to

  9. Sustainability and Uncertainty: Bottom-Up and Top-Down Approaches

    Directory of Open Access Journals (Sweden)

    K. Klint Jensen

    2010-04-01

    Full Text Available The widely used concept of sustainability is seldom precisely defined, and its clarification involves making up one’s mind about a range of difficult questions. One line of research (bottom-up takes sustaining a system over time as its starting point and then infers prescriptions from this requirement. Another line (top-down takes an economical interpretation of the Brundtland Commission’s suggestion that the present generation’s needsatisfaction should not compromise the need-satisfaction of future generations as its starting point. It then measures sustainability at the level of society and infers prescriptions from this requirement. These two approaches may conflict, and in this conflict the top-down approach has the upper hand, ethically speaking. However, the implicit goal in the top-down approach of justice between generations needs to be refined in several dimensions. But even given a clarified ethical goal, disagreements can arise. At present we do not know what substitutions will be possible in the future. This uncertainty clearly affects the prescriptions that follow from the measure of sustainability. Consequently, decisions about how to make future agriculture sustainable are decisions under uncertainty. There might be different judgments on likelihoods; but even given some set of probabilities, there might be disagreement on the right level of precaution in face of the uncertainty.

  10. Bottom-up approach to fabricate nanostructured thin films from colloidal nanocrystal precursors

    Science.gov (United States)

    Shaw, Santosh

    Control over microstructures at the nanoscale (evolves during ligand removal and studied its effect on microstructure related physical properties, e.g., mechanical properties. We further demonstrated that our bottom-up approach can control the grain boundary composition in the final materials by controlling the chemical structure and composition of the ligands and the characteristics of the plasma. We show that with our unprecedented control on grain boundary composition, we can selectively modify grain growth mechanisms, control phase transitions, and affect mechanical properties. By understanding the interaction of plasma species with CNAs and the mass transport in the system, we were able to accelerate the plasma etching rate by more than an order of magnitude. Finally, we demonstrate the applicability of our approach in developing an optics-free lithography in which CNAs are used as resist and as an active material. By selectively masking the interaction of plasma with CNAs with a hard mask we could change the solubility of the exposed regions. This patterning technology can pattern materials which are hard to pattern by traditional inorganic etching based pattern transfer (example, copper, gold).

  11. Visionmaker NYC: A bottom-up approach to finding shared socioeconomic pathways in New York City

    Science.gov (United States)

    Sanderson, E. W.; Fisher, K.; Giampieri, M.; Barr, J.; Meixler, M.; Allred, S. B.; Bunting-Howarth, K. E.; DuBois, B.; Parris, A. S.

    2015-12-01

    Visionmaker NYC is a free, public participatory, bottom-up web application to develop and share climate mitigation and adaptation strategies for New York City neighborhoods. The goal is to develop shared socioeconomic pathways by allowing a broad swath of community members - from schoolchildren to architects and developers to the general public - to input their concepts for a desired future. Visions are comprised of climate scenarios, lifestyle choices, and ecosystem arrangements, where ecosystems are broadly defined to include built ecosystems (e.g. apartment buildings, single family homes, etc.), transportation infrastructure (e.g. highways, connector roads, sidewalks), and natural land cover types (e.g. wetlands, forests, estuary.) Metrics of water flows, carbon cycling, biodiversity patterns, and population are estimated for the user's vision, for the same neighborhood today, and for that neighborhood as it existed in the pre-development state, based on the Welikia Project (welikia.org.) Users can keep visions private, share them with self-defined groups of other users, or distribute them publicly. Users can also propose "challenges" - specific desired states of metrics for specific parts of the city - and others can post visions in response. Visionmaker contributes by combining scenario planning, scientific modelling, and social media to create new, wide-open possibilities for discussion, collaboration, and imagination regarding future, shared socioeconomic pathways.

  12. Computational and experimental approaches for development of methotrexate nanosuspensions by bottom-up nanoprecipitation.

    Science.gov (United States)

    Dos Santos, Aline Martins; Carvalho, Flávia Chiva; Teixeira, Deiver Alessandro; Azevedo, David Lima; de Barros, Wander Miguel; Gremião, Maria Palmira Daflon

    2017-05-30

    Development of nanosuspensions offers a promising tool for formulations involving poorly water-soluble drugs. In this study, methotrexate (MTX) nanosuspensions were prepared using a bottom-up process based on acid-base neutralization reactions. Computational studies were performed to determine structural and electronic properties for isolated molecules and molecular clusters in order to evaluate the mechanism of MTX nanoparticle formation. Computational results indicated that the clusters in zwitterionic and cationic states presented larger dimensions and higher energies of interaction between MTX molecules, which favored aggregation. In contrast, the clusters in the anionic state exhibited lower energies of interaction, indicating aggregation was less likely to occur. Experimental results indicated that the higher the HCl proportion during drug precipitation, the greater the particle size, resulting in micrometric particles (2874-7308nm) (cationic and zwitterionic forms). However, MTX nanoparticles ranging in size from 132 to 186nm were formed using the lowest HCl proportion during drug precipitation (anionic form). In vitro release profiles indicated that the drug release rate from nanosuspension was increased (approximately 2.6 times) over that of the raw material. Overall, computational modeling and experimental analysis were complementary and assisted in the rational design of the nanosuspension based on acid-base reactions. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Balancing Top-Down, Bottom-Up, and Peer-to-Peer Approaches to Sustaining Distance Training

    Science.gov (United States)

    Dudink, Gertrude; Berge, Zane

    2006-01-01

    Many distance training case studies identify distance training leadership as bottom-up, whereas much of the literature suggests a need for strategic, top-down approaches. With change management as an overarching framework, approaches to sustaining distance training that originate at different levels of the organization are explored. Special…

  14. Co-financing of bottom-up approaches towards Broadband Infrastructure Development

    DEFF Research Database (Denmark)

    Williams, Idongesit

    2016-01-01

    networks –leading to the demise of some of these initiatives. This paper proposes co-financing of these networks as a means of sustaining the bottom-up Broadband network. The argument of this paper is anchored on two of developing country cases. One in India and the other in Ghana. One survived...

  15. Microfabrication of shaped MM-scale tissues to study vascular development using modular bottom-up approach

    NARCIS (Netherlands)

    Rivron, N.C.; le Gac, Severine; Vrij, E.J.; Vrij, E; Rouwkema, Jeroen; Wijnperle, Daniël; Truckenmüller, R.K.; van den Berg, Albert; van Blitterswijk, Clemens; Kim, Tae Song; Lee, Yoon-Sik; Chung, Taek-Dong; Jeon, Noo Li; Lee, Sang-Hoon; Suh, Kahp-Yang; Choo, Jaebm; Kim, Yong-Kweon

    2009-01-01

    Recapitulating developmental mechanisms in vitro necessitate models of intermediate complexity, between simple 2D culture and complex in vivo models, which integrate both physical and molecular cues. Here, we describe a cheap and simple bottom-up microfabrication method to build 3D millimeter-scale

  16. Merging bottom-up and top-down precipitation products using a stochastic error model

    Science.gov (United States)

    Maggioni, Viviana; Massari, Christian; Brocca, Luca; Ciabatta, Luca

    2017-04-01

    Accurate quantitative precipitation estimation is of great importance for water resources management, agricultural planning, and forecasting and monitoring of natural hazards such as flash floods and landslides. In situ observations are limited around the Earth, especially in remote areas (e.g., complex terrain, dense vegetation), but currently available satellite precipitation products are able to provide global precipitation estimates with an accuracy that depends upon many factors (e.g., type of storms, temporal sampling, season etc…). Recently, Brocca et al. (2014) have proposed an alternative approach (i.e., SM2RAIN) that allows to estimate rainfall from space by using satellite soil moisture observations. In contrast with classical satellite precipitation products which sense the cloud properties to retrieve the instantaneous precipitation, this new bottom-up approach makes use of two consecutive soil moisture measurements for obtaining an estimate of the fallen precipitation within the interval between two satellite passes. As a result, the nature of the measurement is different and complementary to the one of classical precipitation products and could provide a different valid perspective to improve current satellite rainfall estimates via appropriate integration between the products (i.e., SM2RAIN plus a classical satellite rainfall product). However, whether SM2RAIN is able or not to improve the performance of any state-of-the-art satellite rainfall product is much dependent upon an adequate quantification and characterization of the relative errors of the products. In this study, the stochastic rainfall error model SREM2D (Hossain et al. 2006) is used for characterizing the retrieval error of both SM2RAIN and a state-of-the-art satellite precipitation product (i.e., 3B42RT). The error characterization serves for an optimal integration between SM2RAIN and 3B42RT for enhancing the capability of the resulting integrated product (i.e. SM2RAIN+3B42RT) in

  17. Supporting Frequent Updates in R-Trees: A Bottom-Up Approach

    DEFF Research Database (Denmark)

    Lee, Mong Li; Hsu, Wynne; Jensen, Christian Søndergaard

    2003-01-01

    locality. While the R-tree is the index of choice for multi-dimensional data with low dimensionality, and is thus relevant to these applications, R-tree updates are also relatively inefficient. We present a generalized bottom-up update strategy for R-trees that generalizes existing update techniques......Advances in hardware-related technologies promise to enable new data management applications that monitor continuous processes. In these applications, enormous amounts of state samples are obtained via sensors and are streamed to a database. Further, updates are very frequent and may exhibit...

  18. The end of cheap oil: Bottom-up economic and geologic modeling of aggregate oil production curves

    International Nuclear Information System (INIS)

    Jakobsson, Kristofer; Bentley, Roger; Söderbergh, Bengt; Aleklett, Kjell

    2012-01-01

    There is a lively debate between ‘concerned’ and ‘unconcerned’ analysts regarding the future availability and affordability of oil. We critically examine two interrelated and seemingly plausible arguments for an unconcerned view: (1) there is a growing amount of remaining reserves; (2) there is a large amount of oil with a relatively low average production cost. These statements are unconvincing on both theoretical and empirical grounds. Oil availability is about flows rather than stocks, and average cost is not relevant in the determination of price and output. We subsequently implement a bottom-up model of regional oil production with micro-foundations in both natural science and economics. An oil producer optimizes net present value under the constraints of reservoir dynamics, technological capacity and economic circumstances. Optimal production profiles for different reservoir drives and economic scenarios are derived. The field model is then combined with a discovery model of random sampling from a lognormal field size-frequency distribution. Regional discovery and production scenarios are generated. Our approach does not rely on the simple assumptions of top-down models such as the Hubbert curve – however it leads to the same qualitative result that production peaks when a substantial fraction of the recoverable resource remains in-ground. - Highlights: ► Remaining oil reserves and average costs are of limited use in forecasting. ► We present a bottom-up approach to the modeling of regional oil production. ► Producers maximize net present value under technological and physical constraints. ► Exploration is modeled as random sampling from a lognormal field size distribution. ► Regional production starts declining before half of the recoverable oil is produced.

  19. Plasmonic nanoparticles for a bottom-up approach to fabricate optical metamaterials

    Science.gov (United States)

    Dintinger, José; Scharf, Toralf

    2012-03-01

    We investigate experimentally metallic nanoparticle composites fabricated by bottom-up techniques as potential candidates for optical metamaterials. Depending on the plasmonic resonances sustained by individual NPs and their nanoscale organization into larger meta-atoms, various properties might emerge. Here, the focus of our contribution is on the fabrication and optical characterization of silver NP clusters with a spherical shape. We start with the characterisation of the "bulk" dielectric constants of silver NP inks by spectroscopic ellipsometry for different nanoparticle densities (i.e from strongly diluted dispersions to solid randomly packed films). The inks are then used to prepare spherical nanoparticle clusters by an oil-in water emulsion technique. The study of their optical properties demonstrates their ability to support Mie resonances in the visible. These resonances are associated with the excitation of a magnetic dipole, which constitutes a prerequisite to the realization of metamaterials with negative permeability.

  20. Coupling 2D Finite Element Models and Circuit Equations Using a Bottom-Up Methodology

    Science.gov (United States)

    2002-11-01

    EQUATIONS USING A BOTTOM-UP METHODOLOGY E. G6mezl, J. Roger-Folch2 , A. Gabald6nt and A. Molina’ ’Dpto. de Ingenieria Eldctrica. Universidad Polit...de Ingenieria Elictrica. ETSII. Universidad Politdcnica de Valencia. PO Box 22012, 46071. Valencia, Spain. E-mail: iroger adie.upv.es ABSTRACT The

  1. Bottom-up approach to moduli dynamics in heavy gravitino scenario: Superpotential, soft terms, and sparticle mass spectrum

    International Nuclear Information System (INIS)

    Endo, Motoi; Yamaguchi, Masahiro; Yoshioka, Koichi

    2005-01-01

    The physics of moduli fields is examined in the scenario where the gravitino is relatively heavy with mass of order 10 TeV, which is favored in view of the severe gravitino problem. The form of the moduli superpotential is shown to be determined, if one imposes a phenomenological requirement that no physical CP phase arise in gaugino masses from conformal anomaly mediation. This bottom-up approach allows only two types of superpotential, each of which can have its origins in a fundamental underlying theory such as superstring. One superpotential is the sum of an exponential and a constant, which is identical to that obtained by Kachru et al. (KKLT), and the other is the racetrack superpotential with two exponentials. The general form of soft supersymmetry-breaking masses is derived, and the pattern of the superparticle mass spectrum in the minimal supersymmetric standard model is discussed with the KKLT-type superpotential. It is shown that the moduli mediation and the anomaly mediation make comparable contributions to the soft masses. At the weak scale, the gaugino masses are rather degenerate compared to the minimal supergravity, which bring characteristic features on the superparticle masses. In particular, the lightest neutralino, which often constitutes the lightest superparticle and thus a dark matter candidate, is a considerable admixture of gauginos and Higgsinos. We also find a small mass hierarchy among the moduli, gravitino, and superpartners of the standard-model fields. Cosmological implications of the scenario are briefly described

  2. Change Levers for Unifying Top-Down and Bottom-Up Approaches to the Adoption and Diffusion of e-Learning in Higher Education

    Science.gov (United States)

    Singh, Gurmak; Hardaker, Glenn

    2017-01-01

    Using Giddens' theory of structuration as a theoretical framework, this paper outlines how five prominent United Kingdom universities aimed to integrate top-down and bottom-up approaches to the adoption and diffusion of e-learning. The aim of this paper is to examine the major challenges that arise from the convergence of bottom-up perspectives…

  3. Air pollution in Latin America: Bottom-up Vehicular Emissions Inventory and Atmospheric Modeling

    Science.gov (United States)

    Ibarra Espinosa, S.; Vela, A. V.; Calderon, M. G.; Carlos, G.; Ynoue, R.

    2016-12-01

    Air pollution is a global environmental and health problem. Population of Latin America are facing air quality risks due to high level of air pollution. According to World Health Organization (WHO; 2016), several Latin American cities have high level of pollution. Emissions inventories are a key tool for air quality, however they normally present lack of quality and adequate documentation in developing countries. This work aims to develop air quality assessments in Latin American countries by 1) develop a high resolution emissions inventory of vehicles, and 2) simulate air pollutant concentrations. The bottom-up vehicular emissions inventory used was obtained with the REMI model (Ibarra et al., 2016) which allows to interpolate traffic over road network of Open Street Map to estimate vehicular emissions 24-h, each day of the week. REMI considers several parameters, among them the average age of fleet which was associated with gross domestic product (GDP) per capita. The estimated pollutants are CO, NOx, HC, PM2.5, NO, NO2, CO2, N2O, COV, NH3 and Fuel Consumption. The emissions inventory was performed at the biggest cities, including every capital of Latin America's countries. Initial results shows that the cities with most CO emissions are Buenos Aires 162800 (t/year), São Paulo 152061 (t/year), Campinas 151567 (t/year) and Brasilia 144332 (t/year). The results per capita shows that the city with most CO emissions per capita is Campinas, with 130 (kgCO/hab/year), showed in figure 1. This study also cover high resolution air quality simulations with WRF-Chem main cities in Latin America. Results will be assessed comparing: fuel estimates with local fuel sales, traffic count interpolation with available traffic data set at each city, and comparison between air pollutant simulations with air monitoring observation data. Ibarra, S., R. Ynoue, and S. Mhartain. 2016: "High Resolution Vehicular Emissions Inventory for the Megacity of São Paulo." Manuscript submitted to

  4. Developing a Cognitive Training Strategy for First-Episode Schizophrenia: Integrating Bottom-Up and Top-Down Approaches.

    Science.gov (United States)

    Nuechterlein, Keith H; Ventura, Joseph; Subotnik, Kenneth L; Hayata, Jacqueline N; Medalia, Alice; Bell, Morris D

    2014-07-01

    It is clear that people with schizophrenia typically have cognitive problems in multiple domains as part of their illness. The cognitive deficits are among the main contributors to limitations in their everyday functioning, including their work recovery. Cognitive remediation has been applied successfully to help people with long-term, persistent schizophrenia to improve their cognitive functioning, but it is only beginning to be applied with individuals who have recently had a first episode of psychosis. Several different approaches to cognitive training have been developed. Some approaches emphasize extensive systematic practice with lower-level cognitive processes and building toward higher-level processes ("bottom-up"), while others emphasize greater focus on high-level cognitive processes that normally integrate and organize lower-level processes ("top-down"). Each approach has advantages and disadvantages for a disorder like schizophrenia, with its multiple levels of cognitive dysfunction. In addition, approaches to cognitive remediation differ in the extent to which they systematically facilitate transfer of learning to everyday functioning. We describe in this article the cognitive training approach that was developed for a UCLA study of people with a recent first episode of schizophrenia, a group that may benefit greatly from early intervention that focuses on cognition and recovery of work functioning. This approach integrated bottom-up and top-down computerized cognitive training and incorporated an additional weekly group session to bridge between computerized training and application to everyday work and school functioning.

  5. Bottom-up and top-down solid-state NMR approaches for bacterial biofilm matrix composition

    Science.gov (United States)

    Cegelski, Lynette

    2015-04-01

    The genomics and proteomics revolutions have been enormously successful in providing crucial "parts lists" for biological systems. Yet, formidable challenges exist in generating complete descriptions of how the parts function and assemble into macromolecular complexes and whole-cell assemblies. Bacterial biofilms are complex multicellular bacterial communities protected by a slime-like extracellular matrix that confers protection to environmental stress and enhances resistance to antibiotics and host defenses. As a non-crystalline, insoluble, heterogeneous assembly, the biofilm extracellular matrix poses a challenge to compositional analysis by conventional methods. In this perspective, bottom-up and top-down solid-state NMR approaches are described for defining chemical composition in complex macrosystems. The "sum-of-the-parts" bottom-up approach was introduced to examine the amyloid-integrated biofilms formed by Escherichia coli and permitted the first determination of the composition of the intact extracellular matrix from a bacterial biofilm. An alternative top-down approach was developed to define composition in Vibrio cholerae biofilms and relied on an extensive panel of NMR measurements to tease out specific carbon pools from a single sample of the intact extracellular matrix. These two approaches are widely applicable to other heterogeneous assemblies. For bacterial biofilms, quantitative parameters of matrix composition are needed to understand how biofilms are assembled, to improve the development of biofilm inhibitors, and to dissect inhibitor modes of action. Solid-state NMR approaches will also be invaluable in obtaining parameters of matrix architecture.

  6. A bottom-up approach for optimization of friction stir processing parameters; a study on aluminium 2024-T3 alloy

    International Nuclear Information System (INIS)

    Nadammal, Naresh; Kailas, Satish V.; Suwas, Satyam

    2015-01-01

    Highlights: • An experimental bottom-up approach has been developed for optimizing the process parameters for friction stir processing. • Optimum parameter processed samples were tested and characterized in detail. • Ultimate tensile strength of 1.3 times the base metal strength was obtained. • Residual stresses on the processed surface were only 10% of the yield strength of base metal. • Microstructure observations revealed fine equi-axed grains with precipitate particles at the grain boundaries. - Abstract: Friction stir processing (FSP) is emerging as one of the most competent severe plastic deformation (SPD) method for producing bulk ultra-fine grained materials with improved properties. Optimizing the process parameters for a defect free process is one of the challenging aspects of FSP to mark its commercial use. For the commercial aluminium alloy 2024-T3 plate of 6 mm thickness, a bottom-up approach has been attempted to optimize major independent parameters of the process such as plunge depth, tool rotation speed and traverse speed. Tensile properties of the optimum friction stir processed sample were correlated with the microstructural characterization done using Scanning Electron Microscope (SEM) and Electron Back-Scattered Diffraction (EBSD). Optimum parameters from the bottom-up approach have led to a defect free FSP having a maximum strength of 93% the base material strength. Micro tensile testing of the samples taken from the center of processed zone has shown an increased strength of 1.3 times the base material. Measured maximum longitudinal residual stress on the processed surface was only 30 MPa which was attributed to the solid state nature of FSP. Microstructural observation reveals significant grain refinement with less variation in the grain size across the thickness and a large amount of grain boundary precipitation compared to the base metal. The proposed experimental bottom-up approach can be applied as an effective method for

  7. Controlled synthesis of organic single-crystalline nanowires via the synergy approach of the bottom-up/top-down processes.

    Science.gov (United States)

    Zhuo, Ming-Peng; Zhang, Ye-Xin; Li, Zhi-Zhou; Shi, Ying-Li; Wang, Xue-Dong; Liao, Liang-Sheng

    2018-03-15

    The controlled fabrication of organic single-crystalline nanowires (OSCNWs) with a uniform diameter in the nanoscale via the bottom-up approach, which is just based on weak intermolecular interaction, is a great challenge. Herein, we utilize the synergy approach of the bottom-up and the top-down processes to fabricate OSCNWs with diameters of 120 ± 10 nm through stepwise evolution processes. Specifically, the evolution processes vary from the self-assembled organic micro-rods with a quadrangular pyramid-like end-structure bounded with {111}s and {11-1}s crystal planes to the "top-down" synthesized organic micro-rods with the flat cross-sectional {002}s plane, to the organic micro-tubes with a wall thickness of ∼115 nm, and finally to the organic nanowires. Notably, the anisotropic etching process caused by the protic solvent molecules (such as ethanol) is crucial for the evolution of the morphology throughout the whole top-down process. Therefore, our demonstration opens a new avenue for the controlled-fabrication of organic nanowires, and also contributes to the development of nanowire-based organic optoelectronics such as organic nanowire lasers.

  8. Systematic Correlation Matrix Evaluation (SCoMaE) - a bottom-up, science-led approach to identifying indicators

    Science.gov (United States)

    Mengis, Nadine; Keller, David P.; Oschlies, Andreas

    2018-01-01

    This study introduces the Systematic Correlation Matrix Evaluation (SCoMaE) method, a bottom-up approach which combines expert judgment and statistical information to systematically select transparent, nonredundant indicators for a comprehensive assessment of the state of the Earth system. The methods consists of two basic steps: (1) the calculation of a correlation matrix among variables relevant for a given research question and (2) the systematic evaluation of the matrix, to identify clusters of variables with similar behavior and respective mutually independent indicators. Optional further analysis steps include (3) the interpretation of the identified clusters, enabling a learning effect from the selection of indicators, (4) testing the robustness of identified clusters with respect to changes in forcing or boundary conditions, (5) enabling a comparative assessment of varying scenarios by constructing and evaluating a common correlation matrix, and (6) the inclusion of expert judgment, for example, to prescribe indicators, to allow for considerations other than statistical consistency. The example application of the SCoMaE method to Earth system model output forced by different CO2 emission scenarios reveals the necessity of reevaluating indicators identified in a historical scenario simulation for an accurate assessment of an intermediate-high, as well as a business-as-usual, climate change scenario simulation. This necessity arises from changes in prevailing correlations in the Earth system under varying climate forcing. For a comparative assessment of the three climate change scenarios, we construct and evaluate a common correlation matrix, in which we identify robust correlations between variables across the three considered scenarios.

  9. Trait-based approaches to conservation physiology: forecasting environmental change risks from the bottom up

    OpenAIRE

    Chown, Steven L.

    2012-01-01

    Trait-based approaches have long been a feature of physiology and of ecology. While the latter fields drifted apart in the twentieth century, they are converging owing at least partly to growing similarities in their trait-based approaches, which have much to offer conservation biology. The convergence of spatially explicit approaches to understanding trait variation and its ecological implications, such as encapsulated in community assembly and macrophysiology, provides a significant illustr...

  10. Combining top-down and bottom-up modelling approaches of land use/cover change to support public policies: Application to sustainable management of natural resources in northern Vietnam

    NARCIS (Netherlands)

    Castella, J.C.; Suan Pheng Kam,; Dang Dinh Quang,; Verburg, P.H.; Chu Thai Hoanh,

    2007-01-01

    Over recent years, the scientific community has developed different modelling methodologies of land use/cover change (LUCC) depending on their intended use, and also on the scale of investigation, disciplinary background and scientific tradition of the research teams. Consequently, each LUCC model

  11. [["Conflicting Right": A "Bottom-up" Approach to Map the Problem of Abortion].

    Science.gov (United States)

    Veronesi, Paolo

    The paper examines the particular nature of the rights involved in disciplines related to the termination of pregnancy. It focuses on the ways by which these rights must be appropriately balanced with constitutional rights and values. It also stresses the need of a "botton-up" approach rather than a more restrictive and dangerous "top-down" approach. Only in this way it seems possible to tackle and appreciate the problem in all its actual complexity.

  12. POLITICAL PARTICIPATION OF WOMEN IN ROMANIA - A BOTTOM-UP APPROACH

    Directory of Open Access Journals (Sweden)

    Diana Elena NEAGA

    2014-05-01

    Full Text Available In Romania the access of women to political decision making remains very low (around 10% women in Parliament. The main arguments used to explain this state of affairs are the following: the communist feminism (a contradiction in terms which impose total obedience towards the state and a completely false and forced political empowerment of women which led to an arduous reverse after 1989 (Miroiu 2004;Vinkze 2006; the transition anti-socialist speech that militated in favor of the return to normality, understood as traditional patriarchy (Rueschemeyer, 1994, the gender-developed inequities of transition (Vincze 2006; Miroiu 2004, 2007; the lack of time as a citizenship resource (the double burden (Lister, 2003. Even tough, what meanings do women attach to their status of citizens and how do they take part at political actions, in the context in which compelling structures, like patriarchy, the communist legacy and post-communist transition are overlapping their daily experiences, remains under studied in Romania. In order to fill this gap, in my paper I will present the result of a field work research (qualitative method interviews and focus-groups focused on the way in which women live and experience citizenship, with accent on the perception and signification of their political participation. My arguments will be developed based on a constructivist approach which underline the relations and dependencies between agents (that give meaning to the social roles they play in my paper women from a region in Romania, Hunedoara county and structures (mainly the patriarchal one.

  13. Bottom-up approach for microstructure optimization of sound absorbing materials.

    Science.gov (United States)

    Perrot, Camille; Chevillotte, Fabien; Panneton, Raymond

    2008-08-01

    Results from a numerical study examining micro-/macrorelations linking local geometry parameters to sound absorption properties are presented. For a hexagonal structure of solid fibers, the porosity phi, the thermal characteristic length Lambda('), the static viscous permeability k(0), the tortuosity alpha(infinity), the viscous characteristic length Lambda, and the sound absorption coefficient are computed. Numerical solutions of the steady Stokes and electrical equations are employed to provide k(0), alpha(infinity), and Lambda. Hybrid estimates based on direct numerical evaluation of phi, Lambda('), k(0), alpha(infinity), Lambda, and the analytical model derived by Johnson, Allard, and Champoux are used to relate varying (i) throat size, (ii) pore size, and (iii) fibers' cross-section shapes to the sound absorption spectrum. The result of this paper tends to demonstrate the important effect of throat size in the sound absorption level, cell size in the sound absorption frequency selectivity, and fibers' cross-section shape in the porous material weight reduction. In a hexagonal porous structure with solid fibers, the sound absorption level will tend to be maximized with a 48+/-10 microm throat size corresponding to an intermediate resistivity, a 13+/-8 microm fiber radius associated with relatively small interfiber distances, and convex triangular cross-section shape fibers allowing weight reduction.

  14. Benchmarking energy scenarios for China: perspectives from top-down, economic and bottom-up, technical modelling

    DEFF Research Database (Denmark)

    This study uses a soft-linking methodology to harmonise two complex global top-down and bottom-up models with a regional China focus. The baseline follows the GDP and demographic trends of the Shared Socio-economic Pathways (SSP2) scenario, down-scaled for China, while the carbon tax scenario...... production and 15-18 Gt in carbon dioxide emissions. The highest uncertainty in modelling results can be mapped for China's future coal use in 2050, in particular in electricity production. Sub-regional China features, when incorporated into complex global models, do not increase uncertainty in China...

  15. Modeling Bottom-Up Visual Attention Using Dihedral Group D4 §

    Directory of Open Access Journals (Sweden)

    Puneet Sharma

    2016-08-01

    Full Text Available In this paper, first, we briefly describe the dihedral group D 4 that serves as the basis for calculating saliency in our proposed model. Second, our saliency model makes two major changes in a latest state-of-the-art model known as group-based asymmetry. First, based on the properties of the dihedral group D 4 , we simplify the asymmetry calculations associated with the measurement of saliency. This results is an algorithm that reduces the number of calculations by at least half that makes it the fastest among the six best algorithms used in this research article. Second, in order to maximize the information across different chromatic and multi-resolution features, the color image space is de-correlated. We evaluate our algorithm against 10 state-of-the-art saliency models. Our results show that by using optimal parameters for a given dataset, our proposed model can outperform the best saliency algorithm in the literature. However, as the differences among the (few best saliency models are small, we would like to suggest that our proposed model is among the best and the fastest among the best. Finally, as a part of future work, we suggest that our proposed approach on saliency can be extended to include three-dimensional image data.

  16. Beyond Defining the Smart City. Meeting Top-Down and Bottom-Up Approaches in the Middle

    Directory of Open Access Journals (Sweden)

    Jonas Breuer

    2014-05-01

    Full Text Available This paper aims to better frame the discussion and the various, divergent operationalisations and interpretations of the Smart City concept. We start by explicating top-down approaches to the Smart City, followed by what purely bottom-up initiatives can look like. We provide a clear overview of stakeholders’ different viewpoints on the city of tomorrow. Particularly the consequences and potential impacts of these differing interpretations and approaches should be of specific interest to researchers, policy makers, city administrations, private actors and anyone involved and concerned with life in cities. Therefore the goal of this article is not so much answering the question of what the Smart City is, but rather what the concept can mean for different stakeholders as well as the consequences of their interpretation. We do this by assembling an eclectic overview, bringing together definitions, examples and operationalisations from academia, policy and industry as well as identifying major trends and approaches to realizing the Smart City. We add to the debate by proposing a different approach that starts from the collective, collaboration and context when researching Smart City initiatives.

  17. A bottom-up approach to identifying the maximum operational adaptive capacity of water resource systems to a changing climate

    Science.gov (United States)

    Culley, S.; Noble, S.; Yates, A.; Timbs, M.; Westra, S.; Maier, H. R.; Giuliani, M.; Castelletti, A.

    2016-09-01

    Many water resource systems have been designed assuming that the statistical characteristics of future inflows are similar to those of the historical record. This assumption is no longer valid due to large-scale changes in the global climate, potentially causing declines in water resource system performance, or even complete system failure. Upgrading system infrastructure to cope with climate change can require substantial financial outlay, so it might be preferable to optimize existing system performance when possible. This paper builds on decision scaling theory by proposing a bottom-up approach to designing optimal feedback control policies for a water system exposed to a changing climate. This approach not only describes optimal operational policies for a range of potential climatic changes but also enables an assessment of a system's upper limit of its operational adaptive capacity, beyond which upgrades to infrastructure become unavoidable. The approach is illustrated using the Lake Como system in Northern Italy—a regulated system with a complex relationship between climate and system performance. By optimizing system operation under different hydrometeorological states, it is shown that the system can continue to meet its minimum performance requirements for more than three times as many states as it can under current operations. Importantly, a single management policy, no matter how robust, cannot fully utilize existing infrastructure as effectively as an ensemble of flexible management policies that are updated as the climate changes.

  18. From Cascade to Bottom-Up Ecosystem Services Model: How Does Social Cohesion Emerge from Urban Agriculture?

    Directory of Open Access Journals (Sweden)

    Anna Petit-Boix

    2018-03-01

    Full Text Available Given the expansion of urban agriculture (UA, we need to understand how this system provides ecosystem services, including foundational societal needs such as social cohesion, i.e., people’s willingness to cooperate with one another. Although social cohesion in UA has been documented, there is no framework for its emergence and how it can be modeled within a sustainability framework. In this study, we address this literature gap by showing how the popular cascade ecosystem services model can be modified to include social structures. We then transform the cascade model into a bottom-up causal framework for UA. In this bottom-up framework, basic biophysical (e.g., land availability and social (e.g., leadership ecosystem structures and processes lead to human activities (e.g., learning that can foster specific human attitudes and feelings (e.g., trust. These attitudes and feelings, when aggregated (e.g., social network, generate an ecosystem value of social cohesion. These cause-effect relationships can support the development of causality pathways in social life cycle assessment (S-LCA and further our understanding of the mechanisms behind social impacts and benefits. The framework also supports UA studies by showing the sustainability of UA as an emergent food supplier in cities.

  19. Evaluation of rate law approximations in bottom-up kinetic models of metabolism.

    Science.gov (United States)

    Du, Bin; Zielinski, Daniel C; Kavvas, Erol S; Dräger, Andreas; Tan, Justin; Zhang, Zhen; Ruggiero, Kayla E; Arzumanyan, Garri A; Palsson, Bernhard O

    2016-06-06

    building large scale kinetic models, due to the key role that physiologically meaningful flux and concentration ranges play in determining network dynamics. However, we also showed that detailed mechanistic models show a clear benefit in prediction accuracy when data is available. The work here should help to provide guidance to future kinetic modeling efforts on the choice of rate law and parameterization approaches.

  20. The Challenges of Bottom-up Approach of Natural-Social Integration in China Highland Pasture Management

    Science.gov (United States)

    Ai, Likun

    2017-04-01

    The pasture land covers two fifth of total Chinese land area, which is mainly distributed in western highland of Inner Mongolia, Xinjiang, Tibet, Qinghai, Gansu and Sichuan Provinces. China pasture land is not only in charge of providing food resource to regional people, but also plays important role in highland ecosystem services and biodiversity. Along with global warming and enhanced grazing activity, 90% of China pasture land is facing the threat of land degradation. From middle 1990's, Chinese government has released a series of pasture land conservation policies to prevent further environmental degradation. In the same time, lots of pasture ecosystem and environment change researches are supported by national and regional funding agencies. In this study, by monitoring and investigating this top-down approach of pasture land research and policy making processes, we would like to find out the gaps and problems of current research and policy making on China pasture land conservation, especially focusing on the possibility of establishing the bottom-up approach of natural-social sciences integration to support the pasture land conservation and sustainable pasture land management in highland China.

  1. Recent patterns of methane and nitrous oxide fluxes in the terrestrial biosphere: The bottom-up approach (Invited)

    Science.gov (United States)

    Tian, H.

    2013-12-01

    Accurately estimating methane and nitrous oxide emissions from terrestrial ecosystems is critical for resolving global budgets of these greenhouse gases (GHGs) and continuing to mitigate climate warming. In this study, we use a bottom-up approach to estimate annual budgets of both methane and nitrous oxide in global terrestrial ecosystem during 1981-2010 and analyze the underlying mechanisms responsible for spatial and temporal variations in these GHGs. Both methane and nitrous oxide emissions significantly increased from 1981 to 2010, primarily owing to increased air temperature, nitrogen fertilizer use, and land use change. Methane and nitrous oxide emissions increased the fastest in Asia due to the more prominent environmental changes compared to other continents. The cooling effects by carbon dioxide sink in the terrestrial biosphere might be completely offset by increasing methane and nitrous oxide emissions, resulting in a positive global warming potential. Asia and South America were the largest contributors to increasing global warming potential. This study suggested that current management practices might not be effective enough to reduce future global warming.

  2. Stochastic error model corrections to improve the performance of bottom-up precipitation products for hydrologic applications

    Science.gov (United States)

    Maggioni, V.; Massari, C.; Ciabatta, L.; Brocca, L.

    2016-12-01

    Accurate quantitative precipitation estimation is of great importance for water resources management, agricultural planning, and forecasting and monitoring of natural hazards such as flash floods and landslides. In situ observations are limited around the Earth, especially in remote areas (e.g., complex terrain, dense vegetation), but currently available satellite precipitation products are able to provide global precipitation estimates with an accuracy that depends upon many factors (e.g., type of storms, temporal sampling, season, etc.). The recent SM2RAIN approach proposes to estimate rainfall by using satellite soil moisture observations. As opposed to traditional satellite precipitation methods, which sense cloud properties to retrieve instantaneous estimates, this new bottom-up approach makes use of two consecutive soil moisture measurements for obtaining an estimate of the fallen precipitation within the interval between two satellite overpasses. As a result, the nature of the measurement is different and complementary to the one of classical precipitation products and could provide a different valid perspective to substitute or improve current rainfall estimates. However, uncertainties in the SM2RAIN product are still not well known and could represent a limitation in utilizing this dataset for hydrological applications. Therefore, quantifying the uncertainty associated with SM2RAIN is necessary for enabling its use. The study is conducted over the Italian territory for a 5-yr period (2010-2014). A number of satellite precipitation error properties, typically used in error modeling, are investigated and include probability of detection, false alarm rates, missed events, spatial correlation of the error, and hit biases. After this preliminary uncertainty analysis, the potential of applying the stochastic rainfall error model SREM2D to correct SM2RAIN and to improve its performance in hydrologic applications is investigated. The use of SREM2D for

  3. Una implementación computacional de un modelo de atención visual Bottom-up aplicado a escenas naturales/A Computational Implementation of a Bottom-up Visual Attention Model Applied to Natural Scenes

    Directory of Open Access Journals (Sweden)

    Juan F. Ramírez Villegas

    2011-12-01

    Full Text Available El modelo de atención visual bottom-up propuesto por Itti et al., 2000 [1], ha sido un modelo popular en tanto exhibe cierta evidencia neurobiológica de la visión en primates. Este trabajo complementa el modelo computacional de este fenómeno desde la dinámica realista de una red neuronal. Asimismo, esta aproximación se basa en la existencia de mapas topográficos que representan la prominencia de los objetos del campo visual para la formación de una representación general (mapa de prominencia, esta representación es la entrada de una red neuronal dinámica con interacciones locales y globales de colaboración y competencia que convergen sobre las principales particularidades (objetos de la escena.The bottom-up visual attention model proposed by Itti et al. 2000 [1], has been a popular model since it exhibits certain neurobiological evidence of primates’ vision. This work complements the computational model of this phenomenon using a neural network with realistic dynamics. This approximation is based on several topographical maps representing the objects saliency that construct a general representation (saliency map, which is the input for a dynamic neural network, whose local and global collaborative and competitive interactions converge to the main particularities (objects presented by the visual scene as well.

  4. A harmonized calculation model for transforming EU bottom-up energy efficiency indicators into empirical estimates of policy impacts

    International Nuclear Information System (INIS)

    Horowitz, Marvin J.; Bertoldi, Paolo

    2015-01-01

    This study is an impact analysis of European Union (EU) energy efficiency policy that employs both top-down energy consumption data and bottom-up energy efficiency statistics or indicators. As such, it may be considered a contribution to the effort called for in the EU's 2006 Energy Services Directive (ESD) to develop a harmonized calculation model. Although this study does not estimate the realized savings from individual policy measures, it does provide estimates of realized energy savings for energy efficiency policy measures in aggregate. Using fixed effects panel models, the annual cumulative savings in 2011 of combined household and manufacturing sector electricity and natural gas usage attributed to EU energy efficiency policies since 2000 is estimated to be 1136 PJ; the savings attributed to energy efficiency policies since 2006 is estimated to be 807 PJ, or the equivalent of 5.6% of 2011 EU energy consumption. As well as its contribution to energy efficiency policy analysis, this study adds to the development of methods that can improve the quality of information provided by standardized energy efficiency and sustainable resource indexes. - Highlights: • Impact analysis of European Union energy efficiency policy. • Harmonization of top-down energy consumption and bottom-up energy efficiency indicators. • Fixed effects models for Member States for household and manufacturing sectors and combined electricity and natural gas usage. • EU energy efficiency policies since 2000 are estimated to have saved 1136 Petajoules. • Energy savings attributed to energy efficiency policies since 2006 are 5.6 percent of 2011 combined electricity and natural gas usage.

  5. Save production: a bottom-up energy model for Dutch industry and agriculture

    International Nuclear Information System (INIS)

    Daniels, B.W.; Dril, A.W.N. van

    2007-01-01

    A new version of the model Save production simulates the development of energy use in the Dutch industry and agriculture, including combined heat and power generation. The model disaggregates national energy consumption into fuel types, industrial sectors, energy functions and energy technologies. Simulation is based on microeconomic investment behavior. Examples of model application show results on the penetration of combined heat and power in relation to policy instruments such as CO 2 prices, electricity price support and investment subsidies. Policies that discriminate on CO 2 emissions result in a slightly more efficient heat and power generation. Tailored to the Dutch situation, Save production is well equipped to generate outlooks for the Dutch industrial and agricultural energy use, and for analyzing the role of policies in detail. Its main strength lies in the middle term simulation of decision-making on energy saving technologies and analysis of policy effects. Specific precautions are required when the model is used for analysis on the longer-term, for simulating extreme policies or for the analysis of extremely fluctuating energy prices. (author)

  6. Evaluation of rate law approximations in bottom-up kinetic models of metabolism

    DEFF Research Database (Denmark)

    Du, Bin; Zielinski, Daniel C.; Kavvas, Erol S.

    2016-01-01

    mass action rate law that removes the role of the enzyme from the reaction kinetics. We utilized in vivo data for the human red blood cell to compare the effect of rate law choices against the backdrop of physiological flux and concentration differences. We found that the Michaelis-Menten rate law......Background: The mechanistic description of enzyme kinetics in a dynamic model of metabolism requires specifying the numerical values of a large number of kinetic parameters. The parameterization challenge is often addressed through the use of simplifying approximations to form reaction rate laws....... These approximate rate laws were: 1) a Michaelis-Menten rate law with measured enzyme parameters, 2) a Michaelis-Menten rate law with approximated parameters, using the convenience kinetics convention, 3) a thermodynamic rate law resulting from a metabolite saturation assumption, and 4) a pure chemical reaction...

  7. Residential electricity consumption in Portugal: Findings from top-down and bottom-up models

    International Nuclear Information System (INIS)

    Wiesmann, Daniel; Lima Azevedo, Ines; Ferrao, Paulo; Fernandez, John E.

    2011-01-01

    An econometric study of the Portuguese residential electricity consumption is presented, with a focus on the influence of dwelling characteristics on consumption. The relationship between the dwelling and household characteristics on per capita residential electricity consumption is estimated at two different scales, involving two distinct databases: the first includes data at the municipality level for 2001, the second is the most recent Portuguese consumer expenditure survey that was collected in 2005 and 2006. The results of the analysis at both scales are consistent and indicate that household and dwelling characteristics have a significant influence on residential electricity consumption. Our results show that in Portugal the direct effect of income on electricity consumption is low and becomes smaller when more relevant control variables are included in the analysis. Future demand of electricity in Portugal will be significantly influenced by trends in socioeconomic factors as well as changes in the building stock. These trends should be taken in consideration in the formulation of policy measures to reduce electricity consumption. - Research highlights: → Econometric study of per capita residential electricity consumption in Portugal. → Comparing models at two levels of aggregation: by municipality and by household. → Using proxies for the dwelling characteristics on the municipality level. → Results from both scales are consistent. → Income elasticity is low and the influence of dwelling characteristics is significant.

  8. Evaluating vehicle re-entrained road dust and its potential to deposit to Lake Tahoe: a bottom-up inventory approach.

    Science.gov (United States)

    Zhu, Dongzi; Kuhns, Hampden D; Gillies, John A; Gertler, Alan W

    2014-01-01

    Identifying hotspot areas impacted by emissions of dust from roadways is an essential step for mitigation. This paper develops a detailed road dust PM₁₀ emission inventory using a bottom-up approach and evaluates the potential for the dust to deposit to Lake Tahoe where it can affect water clarity. Previous studies of estimates of quantities of atmospheric deposition of fine sediment particles ("FSP", road dust emission factors, five years of meteorological data, a traffic demand model and GIS analysis was used to estimate the near field deposition of airborne particulate matter roads is approximately 0.6% of the Total Maximum Daily Loadings (TMDL) of FSP that the lake can receive and still meet water quality standards. © 2013 Elsevier B.V. All rights reserved.

  9. A comprehensive estimate of recent carbon sinks in China using both top-down and bottom-up approaches

    Science.gov (United States)

    Jiang, Fei; Chen, Jing M.; Zhou, Lingxi; Ju, Weimin; Zhang, Huifang; Machida, Toshinobu; Ciais, Philippe; Peters, Wouter; Wang, Hengmao; Chen, Baozhang; Liu, Lixin; Zhang, Chunhua; Matsueda, Hidekazu; Sawa, Yousuke

    2016-01-01

    Atmospheric inversions use measurements of atmospheric CO2 gradients to constrain regional surface fluxes. Current inversions indicate a net terrestrial CO2 sink in China between 0.16 and 0.35 PgC/yr. The uncertainty of these estimates is as large as the mean because the atmospheric network historically contained only one high altitude station in China. Here, we revisit the calculation of the terrestrial CO2 flux in China, excluding emissions from fossil fuel burning and cement production, by using two inversions with three new CO2 monitoring stations in China as well as aircraft observations over Asia. We estimate a net terrestrial CO2 uptake of 0.39–0.51 PgC/yr with a mean of 0.45 PgC/yr in 2006–2009. After considering the lateral transport of carbon in air and water and international trade, the annual mean carbon sink is adjusted to 0.35 PgC/yr. To evaluate this top-down estimate, we constructed an independent bottom-up estimate based on ecosystem data, and giving a net land sink of 0.33 PgC/yr. This demonstrates closure between the top-down and bottom-up estimates. Both top-down and bottom-up estimates give a higher carbon sink than previous estimates made for the 1980s and 1990s, suggesting a trend towards increased uptake by land ecosystems in China. PMID:26924637

  10. Reconciling bottom-up and top-down carbon flux estimates using NASA's GEOS-Carb modeling system

    Science.gov (United States)

    Ott, L.; Baker, D. F.; Chatterjee, A.; Collatz, G. J.; Gregg, W. W.; Kawa, S. R.; Oda, T.; Rousseaux, C. S.; Wang, J. S.; Weir, B.

    2016-12-01

    NASA's Carbon Monitoring System (CMS) began in 2010 with the goal of better understanding carbon stocks and fluxes using remote sensing observations. Models play a critical role in achieving this goal by integrating diverse observations of the carbon cycle (e.g. vegetation characteristics, ocean color, night lights, precipitation) to produce estimates of flux, which is not directly observable at a global scale. Built around NASA's Goddard Earth Observing System, version 5 (GEOS-5) atmospheric general circulation model and data assimilation system, the GEOS-Carb system supports CMS by providing data-driven, bottom-up and top-down flux estimates and high-resolution global estimates of carbon dioxide concentration. Because all modeling components use a consistent set of meteorological forcing from GEOS-5, this system provides a unique, physically consistent view of the relationship between carbon flux and climate. We will present 1) an overview of the GEOS-Carb modeling system, products, and available web tools, 2) recent results placing 2015, a record-breaking meteorological year, in the context of the 13-year GEOS-Carb record, and 3) future directions in global modeling in support of science policy and satellite mission planning.

  11. Top-down or bottom-up? Assessing crevassing directions on surging glaciers and developments for physically testing glacier crevassing models.

    Science.gov (United States)

    Rea, B.; Evans, D. J. A.; Benn, D. I.; Brennan, A. J.

    2012-04-01

    Networks of crevasse squeeze ridges (CSRs) preserved on the forelands of many surging glaciers attest to extensive full-depth crevassing. Full-depth connections have been inferred from turbid water up-welling in crevasses and the formation of concertina eskers however, it has not been clearly established if the crevasses formed from the top-down or the bottom-up. A Linear Elastic Fracture Mechanics (LEFM) approach is used to determine the likely propagation direction for Mode I crevasses on seven surging glaciers. Results indicate that, the high extensional surface strain rates are insufficient to promote top-down full-depth crevasses but have sufficient magnitude to penetrate to depths of 4-12 m, explaining the extensive surface breakup accompanying glacier surges. Top-down, full-depth crevassing is only possible when water depth approaches 97% of the crevasse depth. However, the provision of sufficient meltwater is problematic due to the aforementioned extensive shallow surface crevassing. Full-depth, bottom-up crevassing can occur provided basal water pressures are in excess of 80-90% of flotation which is the default for surging and on occasion water pressures may even become artesian. Therefore CSRs, found across many surging glacier forelands and ice margins most likely result from the infilling of basal crevasses formed, for the most part, by bottom-up hydrofracturing. Despite the importance of crevassing for meltwater routing and calving dynamics physically testing numerical crevassing models remains problematic due to technological limitations, changing stress regimes and difficulties associated with working in crevasse zones on glaciers. Mapping of CSR spacing and matching to surface crevasse patterns can facilitate quantitative comparison between the LEFM model and observed basal crevasses provided ice dynamics are known. However, assessing full-depth top-down crevasse propagation is much harder to monitor in the field and no geomorphological record is

  12. A comparison of top-down and bottom-up approaches to benthic habitat mapping to inform offshore wind energy development

    Science.gov (United States)

    LaFrance, Monique; King, John W.; Oakley, Bryan A.; Pratt, Sheldon

    2014-07-01

    Recent interest in offshore renewable energy within the United States has amplified the need for marine spatial planning to direct management strategies and address competing user demands. To assist this effort in Rhode Island, benthic habitat classification maps were developed for two sites in offshore waters being considered for wind turbine installation. Maps characterizing and representing the distribution and extent of benthic habitats are valuable tools for improving understanding of ecosystem patterns and processes, and promoting scientifically-sound management decisions. This project presented the opportunity to conduct a comparison of the methodologies and resulting map outputs of two classification approaches, “top-down” and “bottom-up” in the two study areas. This comparison was undertaken to improve understanding of mapping methodologies and their applicability, including the bottom-up approach in offshore environments where data density tends to be lower, as well as to provide case studies for scientists and managers to consider for their own areas of interest. Such case studies can offer guidance for future work for assessing methodologies and translating them to other areas. The traditional top-down mapping approach identifies biological community patterns based on communities occurring within geologically defined habitat map units, under the concept that geologic environments contain distinct biological assemblages. Alternatively, the bottom-up approach aims to establish habitat map units centered on biological similarity and then uses statistics to identify relationships with associated environmental parameters and determine habitat boundaries. When applied to the two study areas, both mapping approaches produced habitat classes with distinct macrofaunal assemblages and each established statistically strong and significant biotic-abiotic relationships with geologic features, sediment characteristics, water depth, and/or habitat

  13. Linking top-down and bottom-up approaches for assessing the vulnerability of a 100 % renewable energy system in Northern-Italy

    Science.gov (United States)

    Borga, Marco; Francois, Baptiste; Hingray, Benoit; Zoccatelli, Davide; Creutin, Jean-Dominique; brown, Casey

    2016-04-01

    Due to their variable and un-controllable features, integration of Variable Renewable Energies (e.g. solar-power, wind-power and hydropower, denoted as VRE) into the electricity network implies higher production variability and increased risk of not meeting demand. Two approaches are commonly used for assessing this risk and especially its evolution in a global change context (i.e. climate and societal changes); top-down and bottom-up approaches. The general idea of a top-down approach is to drive analysis of global change or of some key aspects of global change on their systems (e.g., the effects of the COP 21, of the deployment of Smart Grids, or of climate change) with chains of loosely linked simulation models within a predictive framework. The bottom-up approach aims to improve understanding of the dependencies between the vulnerability of regional systems and large-scale phenomenon from knowledge gained through detailed exploration of the response to change of the system of interest, which may reveal vulnerability thresholds, tipping points as well as potential opportunities. Brown et al. (2012) defined an analytical framework to merge these two approaches. The objective is to build, a set of Climate Response Functions (CRFs) putting in perspective i) indicators of desired states ("success") and undesired states ("failure") of a system as defined in collaboration with stakeholders 2) exhaustive exploration of the effects of uncertain forcings and imperfect system understanding on the response of the system itself to a plausible set of possible changes, implemented a with multi-dimensionally consistent "stress test" algorithm, and 3) a set "ex post" hydroclimatic and socioeconomic scenarios that provide insight into the differential effectiveness of alternative policies and serve as entry points for the provision of climate information to inform policy evaluation and choice. We adapted this approach for analyzing a 100 % renewable energy system within a region

  14. Heat recovery with heat pumps in non-energy intensive industry: A detailed bottom-up model analysis in the French food and drink industry

    International Nuclear Information System (INIS)

    Seck, Gondia Sokhna; Guerassimoff, Gilles; Maïzi, Nadia

    2013-01-01

    Highlights: • First bottom-up energy model for NEI at 4-digit level of NACE for energy analysis. • Energy end-use modelling due to the unsuitability of end-product/process approach. • Analysis of heat recovery with HP on industrial processes up to 2020 in French F and D. • Energy consumption and emissions drop respectively by 10% compared to 2001 and 9% to 1990. • Results only achieved at heat temperature below 100 °C, concentrated in 1/3 of F and D sectors. - Abstract: Rising energy prices and environmental impacts inevitably encourage industrials to get involved in promoting energy efficiency and emissions reductions. To achieve this goal, we have developed the first detailed bottom-up energy model for Non-Energy Intensive industry (NEI) to study its global energy efficiency and the potential for CO 2 emissions reduction at a 4-digit level of NACE classification. The latter, which is generally neglected in energy analyses, is expected to play an important role in reducing industry energy intensity in the long term due to its economic and energy significance and relatively high growth rate. In this paper, the modelling of NEI is done by energy end-use owing to the unsuitability of the end-product/process approach used in the Energy Intensive industry modelling. As an example, we analysed the impact of heat recovery with heat pumps (HP) on industrial processes up to 2020 on energy savings and CO 2 emissions reductions in the French food and drink industry (F and D), the biggest NEI sector. The results showed HP could be an excellent and very promising energy recovery technology. For further detailed analysis, the depiction of HP investment cost payments is given per temperature range for each F and D subsector. This model constitutes a useful decision-making tool for assessing potential energy savings from investing in efficient technologies at the highest level of disaggregation, as well as a better subsectoral screening

  15. Aid effectiveness from Rome to Busan: some progress but lacking bottom-up approaches or behaviour changes.

    Science.gov (United States)

    Martini, Jessica; Mongo, Roch; Kalambay, Hyppolite; Fromont, Anne; Ribesse, Nathalie; Dujardin, Bruno

    2012-07-01

    The Busan partnership adopted at the 4th High Level Forum on Aid Effectiveness at the end of last year is a significant step forward towards the improvement of aid quality and the promotion of development. In particular, the inclusiveness achieved in Busan and the shift in discourse from 'aid effectiveness' to 'development effectiveness' are emblematic. However, key challenges still remain. Firstly, decision-making should be more bottom-up, finding ways to take into account the populations' needs and experiences and to enhance self-learning dynamics during the policy process. Today, it is particularly necessary to define what 'development' means at country level, according to the aspirations of particular categories of people and meeting operational and local expectations. Secondly, changes in language should be followed by a real change in mindset. Development stakeholders should further adapt their procedures to the reality of complex systems in which development interventions are being dealt with. © 2012 Blackwell Publishing Ltd.

  16. Trophic cascades of bottom-up and top-down forcing on nutrients and plankton in the Kattegat, evaluated by modelling

    DEFF Research Database (Denmark)

    Petersen, Marcell Elo; Maar, Marie; Larsen, Janus

    2017-01-01

    The aim of the study was to investigate the relative importance of bottom-up and top-down forcing on trophic cascades in the pelagic food-web and the implications for water quality indicators (summer phytoplankton biomass and winter nutrients) in relation to management. The 3D ecological model....... On annual basis, the system was more bottom-up than top-down controlled. Microzooplankton was found to play an important role in the pelagic food web as mediator of nutrient and energy fluxes. This study demonstrated that the best scenario for improved water quality was a combined reduction in nutrient...

  17. Modeling Technical Change in Energy System Analysis: Analyzing the Introduction of Learning-by-Doing in Bottom-up Energy Models

    Energy Technology Data Exchange (ETDEWEB)

    Berglund, Christer; Soederholm, Patrik [Luleaa Univ. of Technology (Sweden). Div. of Economics

    2005-02-01

    The main objective of this paper is to provide an overview and a critical analysis of the recent literature on incorporating induced technical change in energy systems models. Special emphasis is put on surveying recent studies aiming at integrating learning-by-doing into bottom-up energy systems models through so-called learning curves, and on analyzing the relevance of learning curve analysis for understanding the process of innovation and technology diffusion in the energy sector. The survey indicates that this model work represents a major advance in energy research, and embeds important policy implications, not the least concerning the cost and the timing of environmental policies (including carbon emission constraints). However, bottom-up energy models with endogenous learning are also limited in their characterization of technology diffusion and innovation. While they provide a detailed account of technical options - which is absent in many top-down models - they also lack important aspects of diffusion behavior that are captured in top-down representations. For instance, they fail in capturing strategic technology diffusion behavior in the energy sector, and they neglect important general equilibrium impacts (such as the opportunity cost of redirecting R and D support to the energy sector). For these reasons bottom-up and top-down models with induced technical change should not be viewed as substitutes but rather as complements.

  18. Calculating systems-scale energy efficiency and net energy returns: A bottom-up matrix-based approach

    International Nuclear Information System (INIS)

    Brandt, Adam R.; Dale, Michael; Barnhart, Charles J.

    2013-01-01

    In this paper we expand the work of Brandt and Dale (2011) on ERRs (energy return ratios) such as EROI (energy return on investment). This paper describes a “bottom-up” mathematical formulation which uses matrix-based computations adapted from the LCA (life cycle assessment) literature. The framework allows multiple energy pathways and flexible inclusion of non-energy sectors. This framework is then used to define a variety of ERRs that measure the amount of energy supplied by an energy extraction and processing pathway compared to the amount of energy consumed in producing the energy. ERRs that were previously defined in the literature are cast in our framework for calculation and comparison. For illustration, our framework is applied to include oil production and processing and generation of electricity from PV (photovoltaic) systems. Results show that ERR values will decline as system boundaries expand to include more processes. NERs (net energy return ratios) tend to be lower than GERs (gross energy return ratios). External energy return ratios (such as net external energy return, or NEER (net external energy ratio)) tend to be higher than their equivalent total energy return ratios. - Highlights: • An improved bottom-up mathematical method for computing net energy return metrics is developed. • Our methodology allows arbitrary numbers of interacting processes acting as an energy system. • Our methodology allows much more specific and rigorous definition of energy return ratios such as EROI or NER

  19. Trophic cascades of bottom-up and top-down forcing on nutrients and plankton in the Kattegat, evaluated by modelling

    Science.gov (United States)

    Petersen, Marcell Elo; Maar, Marie; Larsen, Janus; Møller, Eva Friis; Hansen, Per Juel

    2017-05-01

    The aim of the study was to investigate the relative importance of bottom-up and top-down forcing on trophic cascades in the pelagic food-web and the implications for water quality indicators (summer phytoplankton biomass and winter nutrients) in relation to management. The 3D ecological model ERGOM was validated and applied in a local set-up of the Kattegat, Denmark, using the off-line Flexsem framework. The model scenarios were conducted by changing the forcing by ± 20% of nutrient inputs (bottom-up) and mesozooplankton mortality (top-down), and both types of forcing combined. The model results showed that cascading effects operated differently depending on the forcing type. In the single-forcing bottom-up scenarios, the cascade directions were in the same direction as the forcing. For scenarios involving top-down, there was a skipped-level-transmission in the trophic responses that was either attenuated or amplified at different trophic levels. On a seasonal scale, bottom-up forcing showed strongest response during winter-spring for DIN and Chl a concentrations, whereas top-down forcing had the highest cascade strength during summer for Chl a concentrations and microzooplankton biomass. On annual basis, the system was more bottom-up than top-down controlled. Microzooplankton was found to play an important role in the pelagic food web as mediator of nutrient and energy fluxes. This study demonstrated that the best scenario for improved water quality was a combined reduction in nutrient input and mesozooplankton mortality calling for the need of an integrated management of marine areas exploited by human activities.

  20. Using Top-down and Bottom-up Costing Approaches in LMICs: The Case for Using Both to Assess the Incremental Costs of New Technologies at Scale.

    Science.gov (United States)

    Cunnama, Lucy; Sinanovic, Edina; Ramma, Lebogang; Foster, Nicola; Berrie, Leigh; Stevens, Wendy; Molapo, Sebaka; Marokane, Puleng; McCarthy, Kerrigan; Churchyard, Gavin; Vassall, Anna

    2016-02-01

    Estimating the incremental costs of scaling-up novel technologies in low-income and middle-income countries is a methodologically challenging and substantial empirical undertaking, in the absence of routine cost data collection. We demonstrate a best practice pragmatic approach to estimate the incremental costs of new technologies in low-income and middle-income countries, using the example of costing the scale-up of Xpert Mycobacterium tuberculosis (MTB)/resistance to riframpicin (RIF) in South Africa. We estimate costs, by applying two distinct approaches of bottom-up and top-down costing, together with an assessment of processes and capacity. The unit costs measured using the different methods of bottom-up and top-down costing, respectively, are $US16.9 and $US33.5 for Xpert MTB/RIF, and $US6.3 and $US8.5 for microscopy. The incremental cost of Xpert MTB/RIF is estimated to be between $US14.7 and $US17.7. While the average cost of Xpert MTB/RIF was higher than previous studies using standard methods, the incremental cost of Xpert MTB/RIF was found to be lower. Costs estimates are highly dependent on the method used, so an approach, which clearly identifies resource-use data collected from a bottom-up or top-down perspective, together with capacity measurement, is recommended as a pragmatic approach to capture true incremental cost where routine cost data are scarce. © 2016 The Authors. Health Economics published by John Wiley & Sons Ltd.

  1. Identifying Bottom-Up and Top-Down Components of Attentional Weight by Experimental Analysis and Computational Modeling

    DEFF Research Database (Denmark)

    Nordfang, Maria; Dyrholm, Mads; Bundesen, Claus

    2013-01-01

    . Measured by use of Bundesen’s (1990) computational theory of visual attention, the attentional weight of a singleton object was nearly proportional to the weight of an otherwise similar nonsingleton object, with a factor of proportionality that increased with the strength of the feature contrast...... of the singleton. This result is explained by generalizing the weight equation of Bundesen’s (1990) theory of visual attention such that the attentional weight of an object becomes a product of a bottom-up (feature contrast) and a top-down (feature relevance) component....

  2. Improving the representation of modal choice into bottom-up optimization energy system models - The MoCho-TIMES model

    DEFF Research Database (Denmark)

    Tattini, Jacopo; Ramea, Kalai; Gargiulo, Maurizio

    2018-01-01

    This study presents MoCho-TIMES, an original methodology for incorporating modal choice into energy-economy-environment-engineering (E4) system models. MoCho-TIMES addresses the scarce ability of E4 models to realistically depict behaviour in transport and allows for modal shift towards transit...... and mathematical expressions required to develop the approach. This study develops MoCho-TIMES in the standalone transportation sector of TIMES-DK, the integrated energy system model for Denmark. The model is tested for the Business as Usual scenario and for four alternative scenarios that imply diverse...

  3. Towards nano-organic chemistry: perspectives for a bottom-up approach to the synthesis of low-dimensional carbon nanostructures.

    Science.gov (United States)

    Mercuri, Francesco; Baldoni, Matteo; Sgamellotti, Antonio

    2012-01-21

    Low-dimensional carbon nanostructures, such as nanotubes and graphenes, represent one of the most promising classes of materials, in view of their potential use in nanotechnology. However, their exploitation in applications is often hindered by difficulties in their synthesis and purification. Despite the huge efforts by the research community, the production of nanostructured carbon materials with controlled properties is still beyond reach. Nonetheless, this step is nowadays mandatory for significant progresses in the realization of advanced applications and devices based on low-dimensional carbon nanostructures. Although promising alternative routes for the fabrication of nanostructured carbon materials have recently been proposed, a comprehensive understanding of the key factors governing the bottom-up assembly of simple precursors to form complex systems with tailored properties is still at its early stages. In this paper, following a survey of recent experimental efforts in the bottom-up synthesis of carbon nanostructures, we attempt to clarify generalized criteria for the design of suitable precursors that can be used as building blocks in the production of complex systems based on sp(2) carbon atoms and discuss potential synthetic strategies. In particular, the approaches presented in this feature article are based on the application of concepts borrowed from traditional organic chemistry, such as valence-bond theory and Clar sextet theory, and on their extension to the case of complex carbon nanomaterials. We also present and discuss a validation of these approaches through first-principle calculations on prototypical systems. Detailed studies on the processes involved in the bottom-up fabrication of low-dimensional carbon nanostructures are expected to pave the way for the design and optimization of precursors and efficient synthetic routes, thus allowing the development of novel materials with controlled morphology and properties that can be used in

  4. Exploring the Life Expectancy Increase in Poland in the Context of CVD Mortality Fall: The Risk Assessment Bottom-Up Approach, From Health Outcome to Policies.

    Science.gov (United States)

    Kobza, Joanna; Geremek, Mariusz

    2015-01-01

    Life expectancy at birth is considered the best mortality-based summary indicator of the health status of the population and is useful for measuring long-term health changes. The objective of this article was to present the concept of the bottom-up policy risk assessment approach, developed to identify challenges involved in analyzing risk factor reduction policies and in assessing how the related health indicators have changed over time. This article focuses on the reasons of the significant life expectancy prolongation in Poland over the past 2 decades, thus includes policy context. The methodology details a bottom-up risk assessment approach, a chain of relations between the health outcome, risk factors, and health policy, based on Risk Assessment From Policy to Impact Dimension project guidance. A decline in cardiovascular disease mortality was a key factor that followed life expectancy prolongation. Among basic factors, tobacco and alcohol consumption, diet, physical activity, and new treatment technologies were identified. Poor health outcomes of the Polish population at the beginning of 1990s highlighted the need of the implementation of various health promotion programs, legal acts, and more effective public health policies. Evidence-based public health policy needs translating scientific research into policy and practice. The bottom-up case study template can be one of the focal tools in this process. Accountability for the health impact of policies and programs and legitimization of the decisions of policy makers has become one of the key questions nowadays in European countries' decision-making process and in EU public health strategy. © The Author(s) 2015.

  5. Deciphering the components of regional net ecosystem fluxes following a bottom-up approach for the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    N. Carvalhais

    2010-11-01

    Full Text Available Quantification of ecosystem carbon pools is a fundamental requirement for estimating carbon fluxes and for addressing the dynamics and responses of the terrestrial carbon cycle to environmental drivers. The initial estimates of carbon pools in terrestrial carbon cycle models often rely on the ecosystem steady state assumption, leading to initial equilibrium conditions. In this study, we investigate how trends and inter-annual variability of net ecosystem fluxes are affected by initial non-steady state conditions. Further, we examine how modeled ecosystem responses induced exclusively by the model drivers can be separated from the initial conditions. For this, the Carnegie-Ames-Stanford Approach (CASA model is optimized at set of European eddy covariance sites, which support the parameterization of regional simulations of ecosystem fluxes for the Iberian Peninsula, between 1982 and 2006.

    The presented analysis stands on a credible model performance for a set of sites, that represent generally well the plant functional types and selected descriptors of climate and phenology present in the Iberian region – except for a limited Northwestern area. The effects of initial conditions on inter-annual variability and on trends, results mostly from the recovery of pools to equilibrium conditions; which control most of the inter-annual variability (IAV and both the magnitude and sign of most of the trends. However, by removing the time series of pure model recovery from the time series of the overall fluxes, we are able to retrieve estimates of inter-annual variability and trends in net ecosystem fluxes that are quasi-independent from the initial conditions. This approach reduced the sensitivity of the net fluxes to initial conditions from 47% and 174% to −3% and 7%, for strong initial sink and source conditions, respectively.

    With the aim to identify and improve understanding of the component fluxes that drive the observed trends, the

  6. Evolutionary Steps in the Emergence of Life Deduced from the Bottom-Up Approach and GADV Hypothesis (Top-Down Approach

    Directory of Open Access Journals (Sweden)

    Kenji Ikehara

    2016-01-01

    Full Text Available It is no doubt quite difficult to solve the riddle of the origin of life. So, firstly, I would like to point out the kinds of obstacles there are in solving this riddle and how we should tackle these difficult problems, reviewing the studies that have been conducted so far. After that, I will propose that the consecutive evolutionary steps in a timeline can be rationally deduced by using a common event as a juncture, which is obtained by two counter-directional approaches: one is the bottom-up approach through which many researchers have studied the origin of life, and the other is the top-down approach, through which I established the [GADV]-protein world hypothesis or GADV hypothesis on the origin of life starting from a study on the formation of entirely new genes in extant microorganisms. Last, I will describe the probable evolutionary process from the formation of Earth to the emergence of life, which was deduced by using a common event—the establishment of the first genetic code encoding [GADV]-amino acids—as a juncture for the results obtained from the two approaches.

  7. Middle-Out Approaches to Reform of University Teaching and Learning: Champions striding between the top-down and bottom-up approaches

    Directory of Open Access Journals (Sweden)

    Rick Cummings

    2005-03-01

    Full Text Available In recent years, Australian universities have been driven by a diversity of external forces, including funding cuts, massification of higher education, and changing student demographics, to reform their relationship with students and improve teaching and learning, particularly for those studying off-campus or part-time. Many universities have responded to these forces either through formal strategic plans developed top-down by executive staff or through organic developments arising from staff in a bottom-up approach. By contrast, much of Murdoch University’s response has been led by a small number of staff who have middle management responsibilities and who have championed the reform of key university functions, largely in spite of current policy or accepted practice. This paper argues that the ‘middle-out’ strategy has both a basis in change management theory and practice, and a number of strengths, including low risk, low cost, and high sustainability. Three linked examples of middle-out change management in teaching and learning at Murdoch University are described and the outcomes analyzed to demonstrate the benefits and pitfalls of this approach.

  8. A review of cognitive remediation approaches for schizophrenia: from top-down to bottom-up, brain training to psychotherapy.

    Science.gov (United States)

    Best, Michael W; Bowie, Christopher R

    2017-07-01

    Individuals with psychotic disorders experience profound impairment in neurocognition, which is consistently found to be the best predictor of independent community functioning. Several diverse behavioural treatments designed to enhance neurocognitive abilities have been developed, with subtle to stark differences among them. Various approaches, to varying degrees, have demonstrated success across diffuse outcomes: improved brain structure and function, performance on neuropsychological tests, and community activities associated with daily living. Areas covered: This paper reviews the different approaches to cognitive remediation and the differential effects these approaches have on neurophysiological function, neurocognitive abilities, and real-world community functioning. Cognitive remediation approaches can be broadly classified along two dimensions: 1) treatment target, and 2) treatment modality. Some approaches target more basic perceptual skills, some target higher level executive processes, while some are non-targeted and seek to improve general cognitive ability. With regard to modality, approaches might have little/no therapist involvement and rely exclusively on computerized practice or they may include intensive therapist involvment to generalize neurocognitive change to community functioning. Expert commentary: Compared to other widely implemented treatments for schizophrenia, cognitive remediation produces better effects on outcome measures. It is time for cognitive remediation to be adopted as a best practice in the treatment of schizophrenia.

  9. Increased performance in a bottom-up designed robot by experimentally guided redesign

    DEFF Research Database (Denmark)

    Larsen, Jørgen Christian

    2013-01-01

    the bottom-up, mode-free approach, the authors used the robotic construction kit, LocoKit. This construction kit allows researchers to construct legged robots, without having a mathematical model beforehand. The authors used no specific mathematical model to design the robot, but instead used intuition...... biology, the authors have shown how a bottom-up, model-free design approach can be used to gain specific knowledge on a robotic platform, and also how knowledge can potentially be generalized from this approach. Originality/value – This paper shows that even though a bottom-up, model-free approach......Purpose – Using a bottom-up, model-free approach when building robots is often seen as a less scientific way, compared to a top-down model-based approach, because the results are not easily generalizable to other systems. The authors, however, hypothesize that this problem may be addressed by using...

  10. Two-stage bottom-up tiered approach combining several alternatives for identification of eye irritation potential of chemicals including insoluble or volatile substances.

    Science.gov (United States)

    Hayashi, Kazuhiko; Mori, Taeko; Abo, Takayuki; Ooshima, Kenichi; Hayashi, Takumi; Komano, Tomoko; Takahashi, Yutaka; Sakaguchi, Hitoshi; Takatsu, Akihiko; Nishiyama, Naohiro

    2012-10-01

    For the assessment of eye irritation, one alternative test may not completely replace the rabbit Draize test. In the present study, we examined the predictive potential of a tiered approach analyzing the results from several alternatives (i.e., the Short Time Exposure (STE) test, the EpiOcular assay, the Hen's Egg Test-Chorioallantoic Membrane (HET-CAM) assay and the Bovine Corneal Opacity and Permeability (BCOP) assay) for assessing Globally Harmonized System (GHS) eye irritation categories. Fifty-six chemicals including alcohols, surfactants, and esters were selected with a balanced GHS category and a wide range of chemical classes. From a standpoint of both assessable sample numbers and predictive accuracy, the more favorable tiered approach was considered to be the two-stage bottom-up tiered approach combining the STE test, the EpiOcular assay followed by the BCOP assay (accuracy 69.6%, under prediction rate 8.9%). Moreover, a more favorable predictive capacity (accuracy 71.4%, under prediction rate 3.6%) was obtained when high volatile alcohols/esters with vapor pressures >6 kilopascal (kPa) at 25°C were evaluated with EpiOcular assay instead of the STE test. From these results, the two-stage bottom-up tiered approach combining the STE test, the EpiOcular assay followed by the BCOP assay might be a promising method for the classification of GHS eye irritation category (Not classified (NC), Category 2 (Cat. 2), and Category 1 (Cat. 1)) for a wide range of test chemicals regardless of solubility. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Top-down/bottom-up description of electricity sector for Switzerland using the GEM-E3 computable general equilibrium model

    Energy Technology Data Exchange (ETDEWEB)

    Krakowski, R. A

    2006-06-15

    Participation of the Paul Scherrer Institute (PSI) in the advancement and extension of the multi-region, Computable General Equilibrium (CGE) model GEM-E3 (CES/KUL, 2002) focused primarily on two top-level facets: a) extension of the model database and model calibration, particularly as related to the second component of this study, which is; b) advancement of the dynamics of innovation and investment, primarily through the incorporation of Exogenous Technical Learning (ETL) into he Bottom-Up (BU, technology-based) part of the dynamic upgrade; this latter activity also included the completion of the dynamic coupling of the BU description of the electricity sector with the 'Top-Down' (TD, econometric) description of the economy inherent to the GEM-E3 CGE model. The results of this two- component study are described in two parts that have been combined in this single summary report: Part I describes the methodology and gives illustrative results from the BUTD integration, as well as describing the approach to and giving preliminary results from incorporating an ETL description into the BU component of the overall model; Part II reports on the calibration component of task in terms of: a) formulating a BU technology database for Switzerland based on previous work; incorporation of that database into the GEM-E3 model; and calibrating the BU database with the TD database embodied in the (Swiss) Social Accounting Matrix (SAM). The BUTD coupling along with the ETL incorporation described in Part I represent the major effort embodied in this investigation, but this effort could not be completed without the calibration preamble reported herein as Part II. A brief summary of the scope of each of these key study components is given. (author)

  12. Top-down/bottom-up description of electricity sector for Switzerland using the GEM-E3 computable general equilibrium model

    International Nuclear Information System (INIS)

    Krakowski, R. A.

    2006-06-01

    Participation of the Paul Scherrer Institute (PSI) in the advancement and extension of the multi-region, Computable General Equilibrium (CGE) model GEM-E3 (CES/KUL, 2002) focused primarily on two top-level facets: a) extension of the model database and model calibration, particularly as related to the second component of this study, which is; b) advancement of the dynamics of innovation and investment, primarily through the incorporation of Exogenous Technical Learning (ETL) into he Bottom-Up (BU, technology-based) part of the dynamic upgrade; this latter activity also included the completion of the dynamic coupling of the BU description of the electricity sector with the 'Top-Down' (TD, econometric) description of the economy inherent to the GEM-E3 CGE model. The results of this two- component study are described in two parts that have been combined in this single summary report: Part I describes the methodology and gives illustrative results from the BUTD integration, as well as describing the approach to and giving preliminary results from incorporating an ETL description into the BU component of the overall model; Part II reports on the calibration component of task in terms of: a) formulating a BU technology database for Switzerland based on previous work; incorporation of that database into the GEM-E3 model; and calibrating the BU database with the TD database embodied in the (Swiss) Social Accounting Matrix (SAM). The BUTD coupling along with the ETL incorporation described in Part I represent the major effort embodied in this investigation, but this effort could not be completed without the calibration preamble reported herein as Part II. A brief summary of the scope of each of these key study components is given. (author)

  13. A bottom-up approach to improve local-scale understanding and decision making in responding to climate change

    NARCIS (Netherlands)

    Jakeman, A.; El-Sawah, S.; Guillaume, J.; Filatova, Tatiana; Field, Christopher; Jouzel, Jean; Le Treut, Hervé

    2015-01-01

    To forecast the energy consumtion and carbon emissions in China, this paper established an input-output model with 17 sectors on the macroeconomy level, and an agentbased model on the microeconomy level simulating firms’ innovations in each sector. Results show that due to the uncertainty of

  14. BOOK REVIEW: Tribology on the Small Scale: A Bottom Up Approach to Friction, Lubrication, and Wear Tribology on the Small Scale: A Bottom Up Approach to Friction, Lubrication, and Wear

    Science.gov (United States)

    Hainsworth, S.

    2008-11-01

    Friction, lubrication and wear interactions between materials make considerable differences to how efficient our engines are, whether or not we ski downhill faster than others, or whether the shoes that we are wearing give us sufficient grip to successfully navigate the marble floors of buildings. Traditionally, tribologists have focussed on the macroscopic issues of tribological problems, looking at the design of components, the viscosity of oils and the mechanical properties of surfaces to understand how components interact to give the desired friction and wear properties. However, in the last twenty years there has been an increasing realization that the processes that are controlling these macroscopic interactions are determined by what happens on the atomic and microscopic scale. Further, with the advent of nano- and micro-electro mechanical systems (NEMs and MEMs), macroscopic scale tribological interactions do not influence the tribology of these devices in the same way, and capillary forces and van der Waal's forces play an increased role in determining whether these devices function successfully. This book aims to fill a gap in the area of tribology textbooks by addressing the important advances that have been made in our understanding of the science of nano- and micro-scale tribological interactions. The book is aimed at advanced undergraduate and graduate level students on engineering programmes, academics and scientists interested in atomic and microscopic scale tribological interactions, and engineers and scientists who are not tribologists per se but work in technologies (such as NEMs/MEMs) where tribology is of importance. Whilst the target audience appears to be largely engineers, the book should have wider appeal to physicists, chemists and modellers with interests in tribological interactions. The book consists of twelve chapters with an introduction to the general significance of tribology and a brief history of modern tribology, followed by more

  15. Application of a bottom-up approach for the analysis of rolling contact fatigue in the Dutch high speed line

    NARCIS (Netherlands)

    Schalk, R.; Zoeteman, A.; Nunez Vicencio, Alfredo; Wolfert, A.R.M.

    2017-01-01

    This paper describes the use of big data analytics for understanding the Rolling Contact Fatigue (RCF) phenomena at the High Speed Line (HSL Zuid) in The Netherlands. The authors developed a data model to investigate the impacting parameters in train-track interaction. This has been done to gain

  16. Guidelines for bottom-up approach of nanocarbon film formation from pentacene using heated tungsten on quartz substrate without metal catalyst

    Science.gov (United States)

    Heya, Akira; Matsuo, Naoto

    2018-04-01

    The guidelines for a bottom-up approach of nanographene formation from pentacene using heated tungsten were investigated using a novel method called hot mesh deposition (HMD). In this method, a heated W mesh was set between a pentacene source and a quartz substrate. Pentacene molecules were decomposed by the heated W mesh. The generated pentacene-based decomposed precursors were then deposited on the quartz substrate. The pentacene dimer (peripentacene) was obtained from pentacene by HMD using two heated catalysts. As expected from the calculation with the density functional theory in the literature, it was confirmed that the pentacene dimer can be formed by a reaction between pentacene and 6,13-dihydropentacene. This technique can be applied to the formation of novel nanographene on various substrates without metal catalysts.

  17. The role of spillovers of technological learning in a 'bottom-up' MARKAL model of the global energy system

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, L.; Kypreos, S.

    2002-03-01

    An important criterion in the analysis of climate policy instruments is their ability to stimulate the technological change necessary to enable the long-term shift towards a low-carbon global energy system. In this paper, using a multi-regional 'bottom-up' MARKAL model of the global energy system, which incorporates endogenous technological learning, the effect of spillovers of technological learning in the deployment of electricity generation technologies is examined when Kyoto-like CO{sub 2} constraints are imposed on the global energy system. (author)

  18. A Bottom-Up Building Stock Model for Tracking Regional Energy Targets—A Case Study of Kočevje

    Directory of Open Access Journals (Sweden)

    Marjana Šijanec Zavrl

    2016-10-01

    Full Text Available The paper addresses the development of a bottom-up building stock energy model (BuilS for identification of the building stock renovation potential by considering energy performance of individual buildings through cross-linked data from various public available databases. The model enables integration of various EE and RES measures on the building stock to demonstrate long-term economic and environmental effects of different building stock refurbishment strategies. In the presented case study, the BuilS model was applied in the Kočevje city area and validated using the measured energy consumption of the buildings connected to the city district heating system. Three strategies for improving the building stock in Kočevje towards a more sustainable one are presented with their impact on energy use and CO2 emission projections up to 2030. It is demonstrated that the BuilS bottom-up model enables the setting of a correct baseline regarding energy use of the existing building stock and that such a model is a powerful tool for design and validation of the building stock renovation strategies. It is also shown that the accuracy of the model depends on available information on local resources and local needs, therefore acceleration of the building stock monitoring on the level of each building and continually upgrading of databases with building renovation information is of the utmost importance.

  19. Culture from the Bottom Up

    Science.gov (United States)

    Atkinson, Dwight; Sohn, Jija

    2013-01-01

    The culture concept has been severely criticized for its top-down nature in TESOL, leading arguably to its falling out of favor in the field. But what of the fact that people do "live culturally" (Ingold, 1994)? This article describes a case study of culture from the bottom up--culture as understood and enacted by its individual users.…

  20. Diagnostic study, design and implementation of an integrated model of care in France: a bottom-up process with continuous leadership

    Science.gov (United States)

    de Stampa, Matthieu; Vedel, Isabelle; Mauriat, Claire; Bagaragaza, Emmanuel; Routelous, Christelle; Bergman, Howard; Lapointe, Liette; Cassou, Bernard; Ankri, Joel; Henrard, Jean-Claude

    2010-01-01

    Background Sustaining integrated care is difficult, in large part because of problems encountered securing the participation of health care and social service professionals and, in particular, general practitioners (GPs). Purpose To present an innovative bottom-up and pragmatic strategy used to implement a new integrated care model in France for community-dwelling elderly people with complex needs. Results In the first step, a diagnostic study was conducted with face-to-face interviews to gather data on current practices from a sample of health and social stakeholders working with elderly people. In the second step, an integrated care model called Coordination Personnes Agées (COPA) was designed by the same major stakeholders in order to define its detailed characteristics based on the local context. In the third step, the model was implemented in two phases: adoption and maintenance. This strategy was carried out by a continuous and flexible leadership throughout the process, initially with a mixed leadership (clinician and researcher) followed by a double one (clinician and managers of services) in the implementation phase. Conclusion The implementation of this bottom-up and pragmatic strategy relied on establishing a collaborative dynamic among health and social stakeholders. This enhanced their involvement throughout the implementation phase, particularly among the GPs, and allowed them to support the change practices and services arrangements. PMID:20216954

  1. Diagnostic, design and implementation of an integrated model of care in France: a bottom-up process with a continuous leadership

    Science.gov (United States)

    de Stampa, Matthieu; Vedel, Isabelle; Mauriat, Claire; Bagaragaza, Emmanuel; Routelous, Christelle; Bergman, Howard; Lapointe, Liette; Cassou, Bernard; Ankri, Joel; Henrard, Jean-Claude

    2010-01-01

    Purpose To present an innovative bottom-up and pragmatic strategy used to implement a new integrated care model in France for community-dwelling elderly people with complex needs. Context Sustaining integrated care is difficult, in large part because of problems encountered securing the participation of health care and social service professionals and, in particular, general practitioners (GPs). Case description In the first step, a diagnostic study was conducted with face-to-face interviews to gather data on current practices from a sample of health and social stakeholders working with elderly people. In the second step, an integrated care model called Coordination Personnes Agées (COPA) was designed by the same major stakeholders in order to define its detailed characteristics based on the local context. In the third step, the model was implemented in two phases: adoption and maintenance. This strategy was carried out by a continuous and flexible leadership throughout the process, initially with a mixed leadership (clinician and researcher) followed by a double one (clinician and managers of services) in the implementation phase. Conclusions The implementation of this bottom-up and pragmatic strategy relied on establishing a collaborative dynamic among health and social stakeholders. This enhanced their involvement throughout the implementation phase, particularly among the GPs, and allowed them to support the change practices and services arrangements.

  2. On the advantages of spring magnets compared to pure FePt: Strategy for rare-earth free permanent magnets following a bottom-up approach

    Energy Technology Data Exchange (ETDEWEB)

    Pousthomis, M.; Garnero, C. [Université de Toulouse, UMR 5215 INSA, CNRS, UPS, Laboratoire de Physique et Chimie des Nano-Objets, 135 avenue de Rangueil, F-31077 Toulouse Cedex 4 (France); Marcelot, C.G. [Université de Toulouse, UMR 5215 INSA, CNRS, UPS, Laboratoire de Physique et Chimie des Nano-Objets, 135 avenue de Rangueil, F-31077 Toulouse Cedex 4 (France); Centre d’Elaboration de Matériaux et d’Etudes Structurales, CEMES-CNRS, 29 rue Jeanne Marvig, B.P. 94347, 31055 Toulouse (France); Blon, T.; Cayez, S. [Université de Toulouse, UMR 5215 INSA, CNRS, UPS, Laboratoire de Physique et Chimie des Nano-Objets, 135 avenue de Rangueil, F-31077 Toulouse Cedex 4 (France); Cassignol, C.; Du, V.A.; Krispin, M. [Siemens AG, Corporate Technology, Munich (Germany); Arenal, R. [Transpyrenean Advanced Laboratory for Electron Microscopy (TALEM), INSA - INA, CNRS - Universidad de Zaragoza, 30155 Toulouse (France); Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), U. Zaragoza, C/Mariano Esquillor s/n, 50018 Zaragoza (Spain); Fundacion ARAID, 50018 Zaragoza (Spain); Soulantica, K.; Viau, G. [Université de Toulouse, UMR 5215 INSA, CNRS, UPS, Laboratoire de Physique et Chimie des Nano-Objets, 135 avenue de Rangueil, F-31077 Toulouse Cedex 4 (France); Lacroix, L.-M., E-mail: lmlacroi@insa-toulouse.fr [Université de Toulouse, UMR 5215 INSA, CNRS, UPS, Laboratoire de Physique et Chimie des Nano-Objets, 135 avenue de Rangueil, F-31077 Toulouse Cedex 4 (France); Transpyrenean Advanced Laboratory for Electron Microscopy (TALEM), INSA - INA, CNRS - Universidad de Zaragoza, 30155 Toulouse (France)

    2017-02-15

    Nanostructured magnets benefiting from efficient exchange-coupling between hard and soft grains represent an appealing approach for integrated miniaturized magnetic power sources. Using a bottom-up approach, nanostructured materials were prepared from binary assemblies of bcc FeCo and fcc FePt nanoparticles and compared with pure L1{sub 0}-FePt materials. The use of a bifunctional mercapto benzoic acid yields homogeneous assemblies of the two types of particles while reducing the organic matter amount. The 650 °C thermal annealing, mandatory to allow the L1{sub 0}-FePt phase transition, led to an important interdiffusion and thus decreased drastically the amount of soft phase present in the final composites. The analysis of recoil curves however evidenced the presence of an efficient interphase exchange coupling, which allows obtaining better magnetic performances than pure L1{sub 0} FePt materials, energy product above 100 kJ m{sup −3} being estimated for a Pt content of only 33%. These results clearly evidenced the interest of chemically grown nanoparticles for the preparation of performant spring-magnets, opening promising perspective for integrated subcentimetric magnets with optimized properties.

  3. Implementation status of self-assessment/peer-group discussion program: a bottom-up approach of monitoring/supervision in improving quality of health services.

    Science.gov (United States)

    Kafle, K K; Bhuju, G B; Karkee, S B; Prasad, R R; Shrestha, N; Shrestha, A D; Das, P L; Chataut, B D; Shrestha, A; Suvedi, B K

    2014-01-01

    Monitoring/supervision is an essential component for improving the quality of health services including rational use of medicines. A new bottom-up approach of monitoring/supervision consisting of self-assessment/ peer-group discussion was found to be effective in improving prescribing practices. The new strategy significantly improved the prescribing practices based on standard treatment guidelines. The government has implemented it as a Program in primary health care services of Nepal. This article aims to share the implementation status of the self-assessment/peer-group discussion Program for improving the prescribing practices of common health problems and availability of drugs in the district health system. Concurrent mixed research design was applied for data collection. The data were collected at different levels of health care system using in-depth interviews, participatory observations and documentary analysis. The Management Division, Department of Health Services implemented the Program in 2009-10 and the PHC Revitalization Division, DoHs is the implementation division since 2010-11. The Program comprised revision of participant's and trainer's manuals, training of trainers and prescribers, finalisation of health conditions and indicators, distribution of carbon copy prescription pads, and conduction of peer-group discussions.The Program was implemented in number of districts. The government made the policy decision to implement the Program for monitoring prescribing practices and the availability of free drugs in districts. However, it has covered only few districts and needs escalation to cover all 75 districts of the country.

  4. Identifying the computational requirements of an integrated top-down-bottom-up model for overt visual attention within an active vision system.

    Directory of Open Access Journals (Sweden)

    Sebastian McBride

    Full Text Available Computational visual attention systems have been constructed in order for robots and other devices to detect and locate regions of interest in their visual world. Such systems often attempt to take account of what is known of the human visual system and employ concepts, such as 'active vision', to gain various perceived advantages. However, despite the potential for gaining insights from such experiments, the computational requirements for visual attention processing are often not clearly presented from a biological perspective. This was the primary objective of this study, attained through two specific phases of investigation: 1 conceptual modeling of a top-down-bottom-up framework through critical analysis of the psychophysical and neurophysiological literature, 2 implementation and validation of the model into robotic hardware (as a representative of an active vision system. Seven computational requirements were identified: 1 transformation of retinotopic to egocentric mappings, 2 spatial memory for the purposes of medium-term inhibition of return, 3 synchronization of 'where' and 'what' information from the two visual streams, 4 convergence of top-down and bottom-up information to a centralized point of information processing, 5 a threshold function to elicit saccade action, 6 a function to represent task relevance as a ratio of excitation and inhibition, and 7 derivation of excitation and inhibition values from object-associated feature classes. The model provides further insight into the nature of data representation and transfer between brain regions associated with the vertebrate 'active' visual attention system. In particular, the model lends strong support to the functional role of the lateral intraparietal region of the brain as a primary area of information consolidation that directs putative action through the use of a 'priority map'.

  5. Identifying the computational requirements of an integrated top-down-bottom-up model for overt visual attention within an active vision system.

    Science.gov (United States)

    McBride, Sebastian; Huelse, Martin; Lee, Mark

    2013-01-01

    Computational visual attention systems have been constructed in order for robots and other devices to detect and locate regions of interest in their visual world. Such systems often attempt to take account of what is known of the human visual system and employ concepts, such as 'active vision', to gain various perceived advantages. However, despite the potential for gaining insights from such experiments, the computational requirements for visual attention processing are often not clearly presented from a biological perspective. This was the primary objective of this study, attained through two specific phases of investigation: 1) conceptual modeling of a top-down-bottom-up framework through critical analysis of the psychophysical and neurophysiological literature, 2) implementation and validation of the model into robotic hardware (as a representative of an active vision system). Seven computational requirements were identified: 1) transformation of retinotopic to egocentric mappings, 2) spatial memory for the purposes of medium-term inhibition of return, 3) synchronization of 'where' and 'what' information from the two visual streams, 4) convergence of top-down and bottom-up information to a centralized point of information processing, 5) a threshold function to elicit saccade action, 6) a function to represent task relevance as a ratio of excitation and inhibition, and 7) derivation of excitation and inhibition values from object-associated feature classes. The model provides further insight into the nature of data representation and transfer between brain regions associated with the vertebrate 'active' visual attention system. In particular, the model lends strong support to the functional role of the lateral intraparietal region of the brain as a primary area of information consolidation that directs putative action through the use of a 'priority map'.

  6. Bottom-up Representation of Industrial Energy Efficiency Technologies in Integrated Assessment Models for the Cement Sector

    Energy Technology Data Exchange (ETDEWEB)

    Sathaye, J.; Xu, T.; Galitsky, C.

    2010-08-15

    Adoption of efficient end-use technologies is one of the key measures for reducing greenhouse gas (GHG) emissions. How to effectively analyze and manage the costs associated with GHG reductions becomes extremely important for the industry and policy makers around the world. Energy-climate (EC) models are often used for analyzing the costs of reducing GHG emissions for various emission-reduction measures, because an accurate estimation of these costs is critical for identifying and choosing optimal emission reduction measures, and for developing related policy options to accelerate market adoption and technology implementation. However, accuracies of assessing of GHG-emission reduction costs by taking into account the adoption of energy efficiency technologies will depend on how well these end-use technologies are represented in integrated assessment models (IAM) and other energy-climate models.

  7. A proposed eye irritation testing strategy to reduce and replace in vivo studies using Bottom-Up and Top-Down approaches.

    Science.gov (United States)

    Scott, Laurie; Eskes, Chantra; Hoffmann, Sebastian; Adriaens, Els; Alepée, Nathalie; Bufo, Monica; Clothier, Richard; Facchini, Davide; Faller, Claudine; Guest, Robert; Harbell, John; Hartung, Thomas; Kamp, Hennicke; Varlet, Béatrice Le; Meloni, Marisa; McNamee, Pauline; Osborne, Rosemarie; Pape, Wolfgang; Pfannenbecker, Uwe; Prinsen, Menk; Seaman, Christopher; Spielmann, Horst; Stokes, William; Trouba, Kevin; Berghe, Christine Van den; Goethem, Freddy Van; Vassallo, Marco; Vinardell, Pilar; Zuang, Valérie

    2010-02-01

    In spite of over 20 years of effort, no single in vitro assay has been developed and validated as a full regulatory replacement for the Draize Eye Irritation test. However, companies have been using in vitro methods to screen new formulations and in some cases as their primary assessment of eye irritation potential for many years. The present report shows the outcome of an Expert Meeting convened by the European Centre for the Validation of Alternative Methods in February 2005 to identify test strategies for eye irritation. In this workshop test developers/users were requested to nominate methods to be considered as a basis for the identification of such testing strategies. Assays were evaluated and categorized based on their proposed applicability domains (e.g., categories of irritation severity, modes of action, chemical class, physicochemical compatibility). The analyses were based on the data developed from current practice and published studies, the ability to predict depth of injury (within the applicable range of severity), modes of action that could be addressed and compatibility with different physiochemical forms. The difficulty in predicting the middle category of irritancy (e.g. R36, GHS Categories 2A and 2B) was recognized. The testing scheme proposes using a Bottom-Up (begin with using test methods that can accurately identify non-irritants) or Top-Down (begin with using test methods that can accurately identify severe irritants) progression of in vitro tests (based on expected irritancy). Irrespective of the starting point, the approach would identify non-irritants and severe irritants, leaving all others to the (mild/moderate) irritant GHS 2/R36 categories.

  8. From War to Tolerance? Bottom-up and Top-down Approaches to (Rebuilding Interethnic Ties in the Areas of the Former Yugoslavia

    Directory of Open Access Journals (Sweden)

    Boris Banovac

    2014-01-01

    Full Text Available In recent history the Balkans passed through periods of conflict and violence typical of many post-imperial nation-states that are unable to establish lateral links with their neighbors without or outside the central (imperial connection. In a way, these states imitated historical path of imperial conquests. In this regard, ethnic conflicts that escalated into wars of the former Yugoslavia can be taken as examples of an erratic transformation of post-imperial into modern nation-states that are eager to build up democracy at home and develop peaceful coexistence with others in international environment. Nevertheless, not all multiethnic areas were caught up in violence (e.g. instances of “peace enclaves” in multiethnic areas in Croatia, Bosnia and Heregovina and in Kosovo. Through such examples, which will be illustrated with results of empirical research, we recognize potentials for building tolerance from below. On the other hand, in most other places peace was a follow up of post-conflict processes. In these cases, local potentials of ethnic tolerance were rather weak. The paper provides some examples illustrating regional differences in this regard within Croatia. Actually, the whole process of normalization of ethnic relations in peaceful terms is far from being linear and is hardly going smoothly. Some parts of national elites foster distance and antagonism against the ”others”. On the other hand, especially following EU accession of Croatia, nationalistic rhetoric significantly receded on the level of the official politics. The question is then whether the impact of policies in institutional sphere, both national and international, i.e. top-down approach, is decisive in shaping inter-ethnic relations. The conclusion is that the institutional, top-down arrangements of peace and tolerance cannot be sustainable without concomitant bottom-up processes on micro level, which theoretically corresponds to a “conformant policy” against

  9. Evaluation of modeling NO2 concentrations driven by satellite-derived and bottom-up emission inventories using in situ measurements over China

    Science.gov (United States)

    Liu, Fei; van der A, Ronald J.; Eskes, Henk; Ding, Jieying; Mijling, Bas

    2018-03-01

    Chemical transport models together with emission inventories are widely used to simulate NO2 concentrations over China, but validation of the simulations with in situ measurements has been extremely limited. Here we use ground measurements obtained from the air quality monitoring network recently developed by the Ministry of Environmental Protection of China to validate modeling surface NO2 concentrations from the CHIMERE regional chemical transport model driven by the satellite-derived DECSO and the bottom-up MIX emission inventories. We applied a correction factor to the observations to account for the interferences of other oxidized nitrogen compounds (NOz), based on the modeled ratio of NO2 to NOz. The model accurately reproduces the spatial variability in NO2 from in situ measurements, with a spatial correlation coefficient of over 0.7 for simulations based on both inventories. A negative and positive bias is found for the simulation with the DECSO (slope = 0.74 and 0.64 for the daily mean and daytime only) and the MIX (slope = 1.3 and 1.1) inventories, respectively, suggesting an underestimation and overestimation of NOx emissions from corresponding inventories. The bias between observed and modeled concentrations is reduced, with the slope dropping from 1.3 to 1.0 when the spatial distribution of NOx emissions in the DECSO inventory is applied as the spatial proxy for the MIX inventory, which suggests an improvement of the distribution of emissions between urban and suburban or rural areas in the DECSO inventory compared to that used in the bottom-up inventory. A rough estimate indicates that the observed concentrations, from sites predominantly placed in the populated urban areas, may be 10-40 % higher than the corresponding model grid cell mean. This reduces the estimate of the negative bias of the DECSO-based simulation to the range of -30 to 0 % on average and more firmly establishes that the MIX inventory is biased high over major cities. The

  10. Evaluation of Modeling NO2 Concentrations Driven by Satellite-Derived and Bottom-Up Emission Inventories Using In-Situ Measurements Over China

    Science.gov (United States)

    Liu, Fei; van der A, Ronald J.; Eskes, Henk; Ding, Jieying; Mijling, Bas

    2018-01-01

    Chemical transport models together with emission inventories are widely used to simulate NO2 concentrations over China, but validation of the simulations with in situ measurements has been extremely limited. Here we use ground measurements obtained from the air quality monitoring network recently developed by the Ministry of Environmental Protection of China to validate modeling surface NO2 concentrations from the CHIMERE regional chemical transport model driven by the satellite-derived DECSO and the bottom-up MIX emission inventories. We applied a correction factor to the observations to account for the interferences of other oxidized nitrogen compounds (NOz), based on the modeled ratio of NO2 to NOz. The model accurately reproduces the spatial variability in NO2 from in situ measurements, with a spatial correlation coefficient of over 0.7 for simulations based on both inventories. A negative and positive bias is found for the simulation with the DECSO (slopeD0.74 and 0.64 for the daily mean and daytime only) and the MIX (slopeD1.3 and 1.1) inventories, respectively, suggesting an underestimation and overestimation of NOx emissions from corresponding inventories. The bias between observed and modeled concentrations is reduced, with the slope dropping from 1.3 to 1.0 when the spatial distribution of NOx emissions in the DECSO inventory is applied as the spatial proxy for the MIX inventory, which suggests an improvement of the distribution of emissions between urban and suburban or rural areas in the DECSO inventory compared to that used in the bottom-up inventory. A rough estimate indicates that the observed concentrations, from sites predominantly placed in the populated urban areas, may be 10-40% higher than the corresponding model grid cell mean. This reduces the estimate of the negative bias of the DECSO-based simulation to the range of -30 to 0% on average and more firmly establishes that the MIX inventory is biased high over major cities. The performance of

  11. Quantitative Analysis on the Energy and Environmental Impact of the Korean National Energy R&D Roadmap a Using Bottom-Up Energy System Model

    Directory of Open Access Journals (Sweden)

    Sang Jin Choi

    2017-03-01

    Full Text Available According to the Paris Agreement at the 21st Conference of the Parties, 196 member states are obliged to submit their Intended Nationally Determined Contributions (INDC for every 5 years. As a member, South Korea has already proposed the reduction target and need to submit the achievement as a result of the policies and endeavors in the near future. In this paper, a Korean bottom-up energy system model to support the low-carbon national energy R&D roadmap will be introduced and through the modeling of various scenarios, the mid-to long-term impact on energy consumptions and CO2 emissions will be analyzed as well. The results of the analysis showed that, assuming R&D investments for the 11 types of technologies, savings of 13.7% with regards to final energy consumptions compared to the baseline scenario would be feasible by 2050. Furthermore, in the field of power generation, the generation proportion of new and renewable energy is expected to increase from 3.0% as of 2011 to 19.4% by 2050. This research also suggested that the analysis on the Energy Technology R&D Roadmap based on the model can be used not only for overall impact analysis and R&D portfolio establishment, but also for the development of detailed R&D strategies.

  12. Top-down and bottom-up: Front to back. Comment on "Move me, astonish me... delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates" by Matthew Pelowski et al.

    Science.gov (United States)

    Nadal, Marcos; Skov, Martin

    2017-07-01

    The model presented here [1] is the latest in an evolving series of psychological models aimed at explaining the experience of art, first proposed by Leder and colleagues [2]. The aim of this new version is to ;explicitly connect early bottom-up, artwork-derived processing sequence and outputs to top-down, viewer-derived contribution to the processing sequence; [1, p. 5f & 6]. The ;meeting; of these two processing sequences, the authors contend, is crucial to the understanding of people's responses to art [sections 3.6ff & 4], and therefore the new model's principal motivation.

  13. Altered neuro-endocrine-immune pathways in the irritable bowel syndrome: the top-down and the bottom-up model.

    Science.gov (United States)

    Stasi, Cristina; Rosselli, Massimo; Bellini, Massimo; Laffi, Giacomo; Milani, Stefano

    2012-11-01

    The interaction between the brain and the gut as a pathological mechanism of functional gastrointestinal disorders has been recently recognized in the pathophysiology of the irritable bowel syndrome. Communication between central nervous system and enteric nervous system is two-directional: the brain can influence the function of the enteric nervous system and the gut can influence the brain via vagal and sympathetic afferents. In patients with irritable bowel syndrome, symptoms may be caused by alterations either primarily in the central nervous system (top-down model), or in the gut (bottom-up model), or in a combination of both. The brain-gut axis may be stimulated by various stressors either directed to the central nervous system (exteroreceptive stress) or to the gut (interoceptive stress). Particularly, clinical evidence suggest that in complex and multifactorial diseases such as irritable bowel syndrome, psychological disorders represent significant factors in the pathogenesis and course of the syndrome. Neuroimaging techniques have shown functional differences between central process in healthy subjects and patients with irritable bowel syndrome. Moreover, a high prevalence of psychological/psychiatric disorders have been reported in IBS patients compared to controls. Several data also suggest an alteration of neuro-endocrine and autonomic output to the periphery in these patients. This review will examine and discuss the complex interplay of neuro-endocrine-immune pathways, closely associated with neuropsychiatric disorders.

  14. Bottom-up Initiatives for Photovoltaic: Incentives and Barriers

    Directory of Open Access Journals (Sweden)

    Kathrin Reinsberger

    2014-06-01

    Full Text Available When facing the challenge of restructuring the energy system, bottom-up initiatives can aid the diffusion of decentralized and clean energy technologies. We focused here on a bottom-up initiative of citizen-funded and citizen-operated photovoltaic power plants. The project follows a case study-based approach and examines two different community initiatives. The aim is to investigate the potential incentives and barriers relating to participation or non-participation in predefined community PV projects. Qualitative, as well as quantitative empirical research was used to examine the key factors in the further development of bottom-up initiatives as contributors to a general energy transition.

  15. Integrated Assessment of Energy Policies: A Decomposition of Top-Down and Bottom-Up

    Energy Technology Data Exchange (ETDEWEB)

    Boehringer, Christoph (Univ. of Oldenburg (Germany)); Rutherford, Thomas F. (ETH Zuerich (Switzerland))

    2008-01-15

    The formulation of market equilibrium problems as mixed complementarity problems (MCP) permits integration of bottom-up programming models of the energy system into top-down general equilibrium models of the overall economy. Yet, in practise the MCP approach loses analytical tractability of income effects, when the energy system includes upper and lowrbounds on many decision variables . We therefore advocate the use of complementarity methods to solve only the top-down economic equilibrium model and employ quadratic programming to solve the underlying bottom-up energy supply model. A simple iterative procedure reconciles the equilibrium prices and quantities between both models.

  16. Deep CO2 emission reductions in a global bottom-up model approach

    NARCIS (Netherlands)

    Deetman, Sebastiaan; Hof, Andries; van Vuuren, Detlef P.

    2015-01-01

    Most studies that explore deep GHG emission reduction scenarios assume that climate goals are reached by implementing least-cost emission mitigation options, typically by implementing a global carbon tax. Although such a method provides insight into total mitigation costs, it does not provide much

  17. Synthesis of a Cementitious Material Nanocement Using Bottom-Up Nanotechnology Concept: An Alternative Approach to Avoid CO2 Emission during Production of Cement

    Directory of Open Access Journals (Sweden)

    Byung Wan Jo

    2014-01-01

    Full Text Available The world’s increasing need is to develop smart and sustainable construction material, which will generate minimal climate changing gas during their production. The bottom-up nanotechnology has established itself as a promising alternative technique for the production of the cementitious material. The present investigation deals with the chemical synthesis of cementitious material using nanosilica, sodium aluminate, sodium hydroxide, and calcium nitrate as reacting phases. The characteristic properties of the chemically synthesized nanocement were verified by the chemical composition analysis, setting time measurement, particle size distribution, fineness analysis, and SEM and XRD analyses. Finally, the performance of the nanocement was ensured by the fabrication and characterization of the nanocement based mortar. Comparing the results with the commercially available cement product, it is demonstrated that the chemically synthesized nanocement not only shows better physical and mechanical performance, but also brings several encouraging impacts to the society, including the reduction of CO2 emission and the development of sustainable construction material. A plausible reaction scheme has been proposed to explain the synthesis and the overall performances of the nanocement.

  18. Benchmarking Non-Hardware Balance-of-System (Soft) Costs for U.S. Photovoltaic Systems, Using a Bottom-Up Approach and Installer Survey - Second Edition

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, B.; Ardani, K.; Feldman, D.; Citron, R.; Margolis, R.; Zuboy, J.

    2013-10-01

    This report presents results from the second U.S. Department of Energy (DOE) sponsored, bottom-up data-collection and analysis of non-hardware balance-of-system costs -- often referred to as 'business process' or 'soft' costs -- for U.S. residential and commercial photovoltaic (PV) systems. In service to DOE's SunShot Initiative, annual expenditure and labor-hour-productivity data are analyzed to benchmark 2012 soft costs related to (1) customer acquisition and system design (2) permitting, inspection, and interconnection (PII). We also include an in-depth analysis of costs related to financing, overhead, and profit. Soft costs are both a major challenge and a major opportunity for reducing PV system prices and stimulating SunShot-level PV deployment in the United States. The data and analysis in this series of benchmarking reports are a step toward the more detailed understanding of PV soft costs required to track and accelerate these price reductions.

  19. Integrating top-down and bottom-up approaches to design a cost-effective and equitable programme of measures for adaptation of a river basin to global change

    Science.gov (United States)

    Girard, Corentin; Rinaudo, Jean-Daniel; Pulido-Velazquez, Manuel

    2016-04-01

    Adaptation to the multiple facets of global change challenges the conventional means of sustainably planning and managing water resources at the river basin scale. Numerous demand or supply management options are available, from which adaptation measures need to be selected in a context of high uncertainty of future conditions. Given the interdependency of water users, agreements need to be found at the local level to implement the most effective adaptation measures. Therefore, this work develops an approach combining economics and water resources engineering to select a cost-effective programme of adaptation measures in the context of climate change uncertainty, and to define an equitable allocation of the cost of the adaptation plan between the stakeholders involved. A framework is developed to integrate inputs from the two main approaches commonly used to plan for adaptation. The first, referred to as "top-down", consists of a modelling chain going from global greenhouse gases emission scenarios to local hydrological models used to assess the impact of climate change on water resources. Conversely, the second approach, called "bottom-up", starts from assessing vulnerability at the local level to then identify adaptation measures used to face an uncertain future. The methodological framework presented in this contribution relies on a combination of these two approaches to support the selection of adaptation measures at the local level. Outcomes from these two approaches are integrated to select a cost-effective combination of adaptation measures through a least-cost optimization model developed at the river basin scale. The performances of a programme of measures are assessed under different climate projections to identify cost-effective and least-regret adaptation measures. The issue of allocating the cost of the adaptation plan is considered through two complementary perspectives. The outcome of a negotiation process between the stakeholders is modelled through

  20. Benchmarking Non-Hardware Balance-of-System (Soft) Costs for U.S. Photovoltaic Systems Using a Bottom-Up Approach and Installer Survey

    Energy Technology Data Exchange (ETDEWEB)

    Ardani, Kristen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Feldman, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ong, Sean [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-11-01

    This report presents results from the first U.S. Department of Energy (DOE) sponsored, bottom-up data-collection and analysis of non-hardware balance-of-system costs—often referred to as “business process” or “soft” costs—for residential and commercial photovoltaic (PV) systems. Annual expenditure and labor-hour-productivity data are analyzed to benchmark 2010 soft costs related to the DOE priority areas of (1) customer acquisition; (2) permitting, inspection, and interconnection; (3) installation labor; and (4) installer labor for arranging third-party financing. Annual expenditure and labor-hour data were collected from 87 PV installers. After eliminating outliers, the survey sample consists of 75 installers, representing approximately 13% of all residential PV installations and 4% of all commercial installations added in 2010. Including assumed permitting fees, in 2010 the average soft costs benchmarked in this analysis total $1.50/W for residential systems (ranging from $0.66/W to $1.66/W between the 20th and 80th percentiles). For commercial systems, the median 2010 benchmarked soft costs (including assumed permitting fees) are $0.99/W for systems smaller than 250 kW (ranging from $0.51/W to $1.45/W between the 20th and 80th percentiles) and $0.25/W for systems larger than 250 kW (ranging from $0.17/W to $0.78/W between the 20th and 80th percentiles). Additional soft costs not benchmarked in the present analysis (e.g., installer profit, overhead, financing, and contracting) are significant and would add to these figures. The survey results provide a benchmark for measuring—and helping to accelerate—progress over the next decade toward achieving the DOE SunShot Initiative’s soft-cost-reduction targets. We conclude that the selected non-hardware business processes add considerable cost to U.S. PV systems, constituting 23% of residential PV system price, 17% of small commercial system price, and 5% of large commercial system price (in 2010

  1. Top-down, bottom-up, and around the jungle gym: a social exchange and networks approach to engaging afterschool programs in implementing evidence-based practices.

    Science.gov (United States)

    Smith, Emilie Phillips; Wise, Eileen; Rosen, Howard; Rosen, Alison; Childs, Sharon; McManus, Margaret

    2014-06-01

    This paper uses concepts from social networks and social exchange theories to describe the implementation of evidence-based practices in afterschool programs. The members of the LEGACY Together Afterschool Project team have been involved in conducting collaborative research to migrate a behavioral strategy that has been documented to reduce disruptive behaviors in classroom settings to a new setting-that of afterschool programs. We adapted the Paxis Institute's version of the Good Behavior Game to afterschool settings which differ from in-school settings, including more fluid attendance, multiple age groupings, diverse activities that may take place simultaneously, and differences in staff training and experience (Barrish et al. in J Appl Behav Anal 2(2):119-124, 1969; Embry et al. in The Pax Good Behavior Game. Hazelden, Center City, 2003; Hynes et al. in J Child Serv 4(3):4-20, 2009; Kellam et al. in Drug Alcohol Depend 95:S5-S28, 2008; Tingstrom et al. in Behav Modif 30(2):225-253, 2006). This paper presents the experiences of the three adult groups involved in the implementation process who give first-person accounts of implementation: (1) university-based scientist-practitioners, (2) community partners who trained and provided technical assistance/coaching, and (3) an afterschool program administrator. We introduce here the AIMS model used to frame the implementation process conceptualized by this town-gown collaborative team. AIMS builds upon previous work in implementation science using four phases in which the three collaborators have overlapping roles: approach/engagement, implementation, monitoring, and sustainability. Within all four phases principles of Social Exchange Theory and Social Network Theory are highlighted.

  2. Governing for Integrated Water and Flood Risk Management: Comparing Top-Down and Bottom-Up Approaches in Spain and California

    OpenAIRE

    Anna Serra-Llobet; Esther Conrad; Kathleen Schaefer

    2016-01-01

    Flood risk management in the context of Integrated Water Resource Management (IWRM) is becoming widely accepted as an approach to improving resilience in light of increasing flood risks due to climate change and other factors. This paper contributes to a better understanding of the governance arrangements needed for effectively implement integrated approaches to managing flood risk. We compare how IWRM and flood risk management have been operationalized within “top-down” and “bottom-up” gover...

  3. Increased performance in a bottom-up designed robot by experimentally guided redesign

    DEFF Research Database (Denmark)

    Larsen, Jørgen Christian

    2013-01-01

    Purpose – Using a bottom-up, model-free approach when building robots is often seen as a less scientific way, compared to a top-down model-based approach, because the results are not easily generalizable to other systems. The authors, however, hypothesize that this problem may be addressed by using...... the bottom-up, mode-free approach, the authors used the robotic construction kit, LocoKit. This construction kit allows researchers to construct legged robots, without having a mathematical model beforehand. The authors used no specific mathematical model to design the robot, but instead used intuition...... and took inspiration from biology. The results were afterwards compared with results gained from biology, to see if the robot has some of the key elements the authors were looking for. Findings – With the use of LocoKit as the experimental platform, combined with known experimental measurement methods from...

  4. Modelling single-trial ERP reveals modulation of bottom-up face visual processing by top-down task constraints (in some subjects

    Directory of Open Access Journals (Sweden)

    Guillaume A Rousselet

    2011-06-01

    Full Text Available We studied how task constraints modulate the relationship between single-trial ERPs and image noise. Thirteen subjects performed two interleaved tasks: on different blocks, they saw the same stimuli, but they discriminated either between two faces or between two colours. Stimuli were two pictures of red or green faces that contained from 10% to 80% of phase noise, with 10% increments. Behavioural accuracy followed a noise dependent sigmoid in the identity task but was high and independent of noise level in the colour task. EEG data recorded concurrently were analyzed using a single-trial ANCOVA: we assessed how changes in task constraints modulated ERP noise sensitivity while regressing out the main ERP differences due to identity, colour and task. Single-trial ERP sensitivity to image phase noise started at about 95-110 ms post-stimulus onset. Group analyses showed a significant reduction in noise sensitivity in the colour task compared to the identity task from about 140 ms to 300 ms post-stimulus onset. However, statistical analyses in every subject revealed different results: significant task modulation occurred in 8/13 subjects, one showing an increase and 7 showing a decrease in noise sensitivity in the colour task. Onsets and durations of effects also differed between group and single-trial analyses: at any time point only a maximum of 4 subjects (31% showed results consistent with group analyses. We provide detailed results for all 13 subjects, including a shift function analysis that revealed asymmetric task modulations of single-trial ERP distributions. We conclude that, during face processing, bottom-up sensitivity to phase noise can be modulated by top-down task constraints, in a broad window around the P2, at least in some subjects.

  5. Top-down model estimates, bottom-up inventories, and future projections of global natural and anthropogenic emissions of nitrous oxide

    Science.gov (United States)

    Davidson, E. A.; Kanter, D.

    2013-12-01

    Nitrous oxide (N2O) is the third most abundantly emitted greenhouse gas and the largest remaining emitted ozone depleting substance. It is a product of nitrifying and denitrifying bacteria in soils, sediments and water bodies. Humans began to disrupt the N cycle in the preindustrial era as they expanded agricultural land, used fire for land clearing and management, and cultivated leguminous crops that carry out biological N fixation. This disruption accelerated after the industrial revolution, especially as the use of synthetic N fertilizers became common after 1950. Here we present findings from a new United Nations Environment Programme report, in which we constrain estimates of the anthropogenic and natural emissions of N2O and consider scenarios for future emissions. Inventory-based estimates of natural emissions from terrestrial, marine and atmospheric sources range from 10 to 12 Tg N2O-N/yr. Similar values can be derived for global N2O emissions that were predominantly natural before the industrial revolution. While there was inter-decadal variability, there was little or no consistent trend in atmospheric N2O concentrations between 1730 and 1850, allowing us to assume near steady state. Assuming an atmospheric lifetime of 120 years, the 'top-down' estimate of pre-industrial emissions of 11 Tg N2O-N/yr is consistent with the bottom-up inventories for natural emissions, although the former includes some modest pre-industrial anthropogenic effects (probably business-as-usual scenarios over the period 2013-2050 is ~102 Tg N2O-N; equivalent to ~48 Gt CO2e or ~2730 kt ozone depleting potential. The impact of growing demand for biofuels is highly uncertain, ranging from trivial to the most significant N2O source to date, depending on the types of plants, their nutrient management, the amount of land used for their cultivation, and the fates of their waste products.

  6. Governing for Integrated Water and Flood Risk Management: Comparing Top-Down and Bottom-Up Approaches in Spain and California

    Directory of Open Access Journals (Sweden)

    Anna Serra-Llobet

    2016-10-01

    Full Text Available Flood risk management in the context of Integrated Water Resource Management (IWRM is becoming widely accepted as an approach to improving resilience in light of increasing flood risks due to climate change and other factors. This paper contributes to a better understanding of the governance arrangements needed for effectively implement integrated approaches to managing flood risk. We compare how IWRM and flood risk management have been operationalized within “top-down” and “bottom-up” governance arrangements in the European Union and the United States. We focus in particular on two case study regions, the Catalan coastal region in Spain and the San Francisco Bay Area in California, which have strong similarities in economy, climate, and environmental values, but different institutional settings. Our findings contribute empirical evidence of the need for a balance between “top-down” and “bottom-up” approaches. While the San Francisco Bay Area’s strongly collaborative and participatory approach has generated new connections among flood managers and other stakeholders, the lack of a central entity with the capacity and mandate for on-going coordination and region-wide risk assessments appears to constrain its ability to support integrated and adaptive management. The European Union’s top-down approach and the presence of a central authority at the river basin scale have led to a consolidated regional plan in Catalonia encompassing all phases of flood risk management, but the degree of engagement and opportunities for knowledge-sharing among participants may be more limited.

  7. Police reform from the bottom up

    African Journals Online (AJOL)

    Over the past two decades the theories and strategies associated with institutional reform of the police as public agency have been a source of invigoration for ... Criminology, Faculty of Law at the University of Cape. Town. Elrena van der Spuy*. Elrena.vanderspuy@uct.ac.za. Title: Police reform from the bottom up: officers ...

  8. Move me, astonish me… delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates

    Science.gov (United States)

    Pelowski, Matthew; Markey, Patrick S.; Forster, Michael; Gerger, Gernot; Leder, Helmut

    2017-07-01

    This paper has a rather audacious purpose: to present a comprehensive theory explaining, and further providing hypotheses for the empirical study of, the multiple ways by which people respond to art. Despite common agreement that interaction with art can be based on a compelling, and occasionally profound, psychological experience, the nature of these interactions is still under debate. We propose a model, The Vienna Integrated Model of Art Perception (VIMAP), with the goal of resolving the multifarious processes that can occur when we perceive and interact with visual art. Specifically, we focus on the need to integrate bottom-up, artwork-derived processes, which have formed the bulk of previous theoretical and empirical assessments, with top-down mechanisms which can describe how individuals adapt or change within their processing experience, and thus how individuals may come to particularly moving, disturbing, transformative, as well as mundane, results. This is achieved by combining several recent lines of theoretical research into a new integrated approach built around three processing checks, which we argue can be used to systematically delineate the possible outcomes in art experience. We also connect our model's processing stages to specific hypotheses for emotional, evaluative, and physiological factors, and address main topics in psychological aesthetics including provocative reactions-chills, awe, thrills, sublime-and difference between ;aesthetic; and ;everyday; emotional response. Finally, we take the needed step of connecting stages to functional regions in the brain, as well as broader core networks that may coincide with the proposed cognitive checks, and which taken together can serve as a basis for future empirical and theoretical art research.

  9. Morphological and molecular phylogenetic context of the angiosperms: contrasting the 'top-down' and 'bottom-up' approaches used to infer the likely characteristics of the first flowers.

    Science.gov (United States)

    Bateman, Richard M; Hilton, Jason; Rudall, Paula J

    2006-01-01

    Recent attempts to address the long-debated 'origin' of the angiosperms depend on a phylogenetic framework derived from a matrix of taxa versus characters; most assume that empirical rigour is proportional to the size of the matrix. Sequence-based genotypic approaches increase the number of characters (nucleotides and indels) in the matrix but are confined to the highly restricted spectrum of extant species, whereas morphology-based approaches increase the number of phylogenetically informative taxa (including fossils) at the expense of accessing only a restricted spectrum of phenotypic characters. The two approaches are currently delivering strongly contrasting hypotheses of relationship. Most molecular studies indicate that all extant gymnosperms form a natural group, suggesting surprisingly early divergence of the lineage that led to angiosperms, whereas morphology-only phylogenies indicate that a succession of (mostly extinct) gymnosperms preceded a later angiosperm origin. Causes of this conflict include: (i) the vast phenotypic and genotypic lacuna, largely reflecting pre-Cenozoic extinctions, that separates early-divergent living angiosperms from their closest relatives among the living gymnosperms; (ii) profound uncertainty regarding which (a) extant and (b) extinct angiosperms are most closely related to gymnosperms; and (iii) profound uncertainty regarding which (a) extant and (b) extinct gymnosperms are most closely related to angiosperms, and thus best serve as 'outgroups' dictating the perceived evolutionary polarity of character transitions among the early-divergent angiosperms. These factors still permit a remarkable range of contrasting, yet credible, hypotheses regarding the order of acquisition of the many phenotypic characters, reproductive and vegetative, that distinguish 'classic' angiospermy from 'classic' gymnospermy. The flower remains ill-defined and its mode (or modes) of origin remains hotly disputed; some definitions and hypotheses of

  10. Bottom-up coarse-grained models with predictive accuracy and transferability for both structural and thermodynamic properties of heptane-toluene mixtures

    International Nuclear Information System (INIS)

    Dunn, Nicholas J. H.; Noid, W. G.

    2016-01-01

    This work investigates the promise of a “bottom-up” extended ensemble framework for developing coarse-grained (CG) models that provide predictive accuracy and transferability for describing both structural and thermodynamic properties. We employ a force-matching variational principle to determine system-independent, i.e., transferable, interaction potentials that optimally model the interactions in five distinct heptane-toluene mixtures. Similarly, we employ a self-consistent pressure-matching approach to determine a system-specific pressure correction for each mixture. The resulting CG potentials accurately reproduce the site-site rdfs, the volume fluctuations, and the pressure equations of state that are determined by all-atom (AA) models for the five mixtures. Furthermore, we demonstrate that these CG potentials provide similar accuracy for additional heptane-toluene mixtures that were not included their parameterization. Surprisingly, the extended ensemble approach improves not only the transferability but also the accuracy of the calculated potentials. Additionally, we observe that the required pressure corrections strongly correlate with the intermolecular cohesion of the system-specific CG potentials. Moreover, this cohesion correlates with the relative “structure” within the corresponding mapped AA ensemble. Finally, the appendix demonstrates that the self-consistent pressure-matching approach corresponds to minimizing an appropriate relative entropy.

  11. Bottom-Up modeling, a tool for decision support for long-term policy on energy and environment - The TIMES model applied to the energy intensive industries

    International Nuclear Information System (INIS)

    Djemaa, A.

    2009-01-01

    Among the energy users in France and Europe, some industrial sectors are very important and should have a key role when assessing the final energy demand patterns in the future. The aim of our work is to apply a prospective model for the long range analysis of energy/technology choices in the industrial sector, focussing on the energy-intensive sectors. The modelling tool applied in this study is the TIMES model (family of best known MARKAL model). It is an economic linear programming model generator for local, national or multi regional energy systems, which provides a technology-rich basis for estimating energy dynamics over a long term, multi period time. We illustrate our work with nine energy-intensive industrial sectors: paper, steel, glass, cement, lime, tiles, brick, ceramics and plaster. It includes a detailed description of the processes involved in the production of industrial products, providing typical energy uses in each process step. In our analysis, we identified for each industry, several commercially available state-of-the-art technologies, characterized and chosen by the Model on the basis of cost effectiveness. Furthermore, we calculated potential energy savings, carbon dioxide emissions' reduction and we estimated the energy impact of a technological rupture. This work indicates that there still exists a significant potential for energy savings and carbon dioxide emissions' reduction in all industries. (author)

  12. Bridging the Gap between the Nanometer-Scale Bottom-Up and Micrometer-Scale Top-Down Approaches for Site-Defined InP/InAs Nanowires.

    Science.gov (United States)

    Zhang, Guoqiang; Rainville, Christophe; Salmon, Adrian; Takiguchi, Masato; Tateno, Kouta; Gotoh, Hideki

    2015-11-24

    This work presents a method that bridges the gap between the nanometer-scale bottom-up and micrometer-scale top-down approaches for site-defined nanostructures, which has long been a significant challenge for applications that require low-cost and high-throughput manufacturing processes. We realized the bridging by controlling the seed indium nanoparticle position through a self-assembly process. Site-defined InP nanowires were then grown from the indium-nanoparticle array in the vapor-liquid-solid mode through a "seed and grow" process. The nanometer-scale indium particles do not always occupy the same locations within the micrometer-scale open window of an InP exposed substrate due to the scale difference. We developed a technique for aligning the nanometer-scale indium particles on the same side of the micrometer-scale window by structuring the surface of a misoriented InP (111)B substrate. Finally, we demonstrated that the developed method can be used to grow a uniform InP/InAs axial-heterostructure nanowire array. The ability to form a heterostructure nanowire array with this method makes it possible to tune the emission wavelength over a wide range by employing the quantum confinement effect and thus expand the application of this technology to optoelectronic devices. Successfully pairing a controllable bottom-up growth technique with a top-down substrate preparation technique greatly improves the potential for the mass-production and widespread adoption of this technology.

  13. Teaching Listening Comprehension: Bottom-Up Approach

    Science.gov (United States)

    Khuziakhmetov, Anvar N.; Porchesku, Galina V.

    2016-01-01

    Improving listening comprehension skills is one of the urgent contemporary educational problems in the field of second language acquisition. Understanding how L2 listening comprehension works can have a serious influence on language pedagogy. The aim of the paper is to discuss the practical and methodological value of the notion of the perception…

  14. The protection pyramid approach : A contribution to the protection of internally displaced persons by combining bottom up coping mechanisms and top down protection strategies into a partnership approach to protection

    NARCIS (Netherlands)

    Janssen, Laura

    2017-01-01

    In het huidige debat over de bescherming van Intern Ontheemde Mensen (IDPs) spelen twee groepen actoren een rol. Enerzijds de ontheemden zelf (Bottom Up actoren genoemd), anderzijds de Staat, niet-Statelijke actoren en andere hulpverleners (Top Down actoren). Van oudsher wordt er meer aandacht

  15. A study of electricity planning in Thailand: An integrated top-down and bottom-up Computable General Equilibrium (CGE) modeling analysis

    Science.gov (United States)

    Srisamran, Supree

    This dissertation examines the potential impacts of three electricity policies on the economy of Thailand in terms of macroeconomic performance, income distribution, and unemployment rate. The three considered policies feature responses to potential disruption of imported natural gas used in electricity generation, alternative combinations (portfolios) of fuel feedstock for electricity generation, and increases in investment and local electricity consumption. The evaluation employs Computable General Equilibrium (CGE) approach with the extension of electricity generation and transmission module to simulate the counterfactual scenario for each policy. The dissertation consists of five chapters. Chapter one begins with a discussion of Thailand's economic condition and is followed by a discussion of the current state of electricity generation and consumption and current issues in power generation. The security of imported natural gas in power generation is then briefly discussed. The persistence of imported natural gas disruption has always caused trouble to the country, however, the economic consequences of this disruption have not yet been evaluated. The current portfolio of power generation and the concerns it raises are then presented. The current portfolio of power generation is heavily reliant upon natural gas and so needs to be diversified. Lastly, the anticipated increase in investment and electricity consumption as a consequence of regional integration is discussed. Chapter two introduces the CGE model, its background and limitations. Chapter three reviews relevant literature of the CGE method and its application in electricity policies. In addition, the submodule characterizing the network of electricity generation and distribution and the method of its integration with the CGE model are explained. Chapter four presents the findings of the policy simulations. The first simulation illustrates the consequences of responses to disruptions in natural gas imports

  16. Neoliberalism Viewed From the Bottom Up

    DEFF Research Database (Denmark)

    Danneris, Sophie

    2017-01-01

    Drawing on the assumption that it is pivotal to include a bottom up perspective to understand the way in which the welfare system functions, this chapter sets out to explore the lived experience of neoliberalism. The purpose is to gain insight into the consequences of neoliberalism from...... the viewpoint of the vulnerable benefit claimants who encounter it on a daily basis. The analysis is based on a qualitative longitudinal study conducted from 2013 to 2015, which shows how, in varying ways, clients routinely cope with being part of a neoliberal welfare state: by resignation, by taking action...

  17. A top-down / bottom-up approach for multi-actors and multi-criteria assessment of mining projects for sustainable development. Application on Arlit Uranium mines (Niger)

    International Nuclear Information System (INIS)

    Chamaret, A.

    2007-06-01

    This thesis aims to appraise the relevance of using an hybrid top-down / bottom-up approach to evaluate mining projects in the perspective of sustainable development. With the advent of corporate social responsibility and sustainable development concepts, new social expectations have appeared towards companies that go beyond a sole requirement of profit earning capacity. If companies do not answer to these expectations, they risk to lose their social legitimacy. Traditionally associated with social, environmental, economical and political impacts and risks, mining activity is particularly concerned by these new issues. Whereas mineral resources needs have never been so high, mining companies are now expected to limit their negative effects and to take into account their different audiences' expectations in order to define, together, the terms of their social license to operate. Considering the diversity of issues, scales, actors and contexts, the challenge is real and necessitates tools to better understand issues and to structure dialogues. Based on the Uranium mines of Arlit (Niger) case study, this work shows that associating participatory approaches to structuration tools and literature propositions, appears as an efficient formula to better organize issues diversity and to build a structured dialogue between mining companies and their stakeholders. First Part aims to present the theoretical, institutional and sectorial contexts of the thesis. Second Part exposes work and results of the evaluation carried out in Niger. And, Third Part, shows the conclusions that can be derived from this work and presents a proposal for an evaluation framework, potentially applicable to other mining sites. (author)

  18. Combining bottom-up and top-down

    International Nuclear Information System (INIS)

    Boehringer, Christoph; Rutherford, Thomas F.

    2008-01-01

    We motivate the formulation of market equilibrium as a mixed complementarity problem which explicitly represents weak inequalities and complementarity between decision variables and equilibrium conditions. The complementarity format permits an energy-economy model to combine technological detail of a bottom-up energy system with a second-best characterization of the over-all economy. Our primary objective is pedagogic. We first lay out the complementarity features of economic equilibrium and demonstrate how we can integrate bottom-up activity analysis into a top-down representation of the broader economy. We then provide a stylized numerical example of an integrated model - within both static and dynamic settings. Finally, we present illustrative applications to three themes figuring prominently on the energy policy agenda of many industrialized countries: nuclear phase-out, green quotas, and environmental tax reforms. (author)

  19. Combining bottom-up and top-down

    Energy Technology Data Exchange (ETDEWEB)

    Boehringer, Christoph [Department of Economics, University of Oldenburg, Oldenburg (Germany); Centre for European Economic Research (ZEW), Mannheim (Germany); Rutherford, Thomas F. [Ann Arbor, Michigan (United States)

    2008-03-15

    We motivate the formulation of market equilibrium as a mixed complementarity problem which explicitly represents weak inequalities and complementarity between decision variables and equilibrium conditions. The complementarity format permits an energy-economy model to combine technological detail of a bottom-up energy system with a second-best characterization of the over-all economy. Our primary objective is pedagogic. We first lay out the complementarity features of economic equilibrium and demonstrate how we can integrate bottom-up activity analysis into a top-down representation of the broader economy. We then provide a stylized numerical example of an integrated model - within both static and dynamic settings. Finally, we present illustrative applications to three themes figuring prominently on the energy policy agenda of many industrialized countries: nuclear phase-out, green quotas, and environmental tax reforms. (author)

  20. An exponential growth model with decreasing r captures bottom-up effects on the population growth of Aphis glycines Matsumura (Hemiptera: Aphididae)

    NARCIS (Netherlands)

    Costamagna, A.C.; Werf, van der W.; Bianchi, F.J.J.A.; Landis, D.A.

    2007-01-01

    1 There is ample evidence that the life history and population dynamics of aphids are closely linked to plant phenology. Based on life table studies, it has been proposed that the growth of aphid populations could be modeled with an exponential growth model, with r decreasing linearly with time.

  1. Bottom-up Representation of Industrial Energy Efficiency Technologies in Integrated Assessment Models for the U.S. Pulp and Paper Sector

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Tengfang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sathaye, Jayant [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kramer, Klaas Jan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-07-01

    Adoption of efficient end-use technologies is one of the key measures for reducing greenhouse gas (GHG) emissions. How to effectively analyze and manage the costs associated with GHG reductions becomes extremely important for the industry and policy makers around the world. Energy-climate (EC) models are often used for analyzing the costs of reducing GHG emissions for various emission-reduction measures, because an accurate estimation of these costs is critical for identifying and choosing optimal emission reduction measures, and for developing related policy options to accelerate market adoption and technology implementation. However, accuracies of assessing GHG-emission reduction costs by taking into account the adoption of energy efficiency technologies will depend on how well these end-use technologies are represented in integrated assessment models (IAM) and other energy-climate models. In this report, we first conduct a brief review of different representations of end-use technologies (mitigation measures) in various energy-climate models, followed by the problem statement, and a description of the basic concepts of quantifying the cost of conserved energy including integrating no-regrets options.

  2. Development of Bottom-up Representation of Industrial Energy Efficiency Technologies in Integrated Assessment Models for the Iron and Steel Sector

    Energy Technology Data Exchange (ETDEWEB)

    Xu, T.T.; Sathaye, J.; Galitsky, C.

    2010-09-30

    Adoption of efficient end-use technologies is one of the key measures for reducing greenhouse gas (GHG) emissions. With the working of energy programs and policies on carbon regulation, how to effectively analyze and manage the costs associated with GHG reductions become extremely important for the industry and policy makers around the world. Energy-climate (EC) models are often used for analyzing the costs of reducing GHG emissions (e.g., carbon emission) for various emission-reduction measures, because an accurate estimation of these costs is critical for identifying and choosing optimal emission reduction measures, and for developing related policy options to accelerate market adoption and technology implementation. However, accuracies of assessing of GHG-emission reduction costs by taking into account the adoption of energy efficiency technologies will depend on how well these end-use technologies are represented in integrated assessment models (IAM) and other energy-climate models. In this report, we first conduct brief overview on different representations of end-use technologies (mitigation measures) in various energy-climate models, followed by problem statements, and a description of the basic concepts of quantifying the cost of conserved energy including integrating non-regrets options. A non-regrets option is defined as a GHG reduction option that is cost effective, without considering their additional benefits related to reducing GHG emissions. Based upon these, we develop information on costs of mitigation measures and technological change. These serve as the basis for collating the data on energy savings and costs for their future use in integrated assessment models. In addition to descriptions of the iron and steel making processes, and the mitigation measures identified in this study, the report includes tabulated databases on costs of measure implementation, energy savings, carbon-emission reduction, and lifetimes. The cost curve data on mitigation

  3. Bottom-up grammar analysis : a functional formulation

    NARCIS (Netherlands)

    Jeuring, J.T.; Swierstra, D.

    1994-01-01

    This paper discusses bottom-up grammar analysis problems such as te EMPTY problem and the FIRST problem. It defines a general class of bottom-up grammar analysis problems, and from this definition it derives a functional program for performing bottom-up grammar analysis. The derivation is purely

  4. Bottom-up silicon nanowire-based thermoelectric microgenerators

    Science.gov (United States)

    Dávila, D.; Huber, R.; Hierold, C.

    2015-12-01

    In this work, bottom-up intrinsic crystalline Si nanowire arrays in combination with top-down microfabrication techniques and a vertical device architecture have been proposed to develop an all-silicon nanostructured thermoelectric generator. To fabricate this device, a suitable vertical integration of Si NWs on patterned microstructures, which define the thermoelectric legs of the generator, has been achieved by bonding top and bottom silicon structures through nanowires. The process has been proven to be a feasible approach that employs a regrowth process of the nanowires for bonding purposes.

  5. Emerging bioeconomy : Assessing the implications of advanced bioenergy and biochemicals with bottom-up and top-down modelling approaches

    NARCIS (Netherlands)

    Tsiropoulos, I.

    2016-01-01

    Biomass is expected to play a key role in reducing greenhouse gas emissions holding global temperature rise to well below 2oC, as agreed on at the 21st Conference of Parties in Paris. The diversity of biomass production systems (feedstocks, regions, end-uses) and their varying performance from an

  6. Bottom-up grammar analysis : a functional formulation

    OpenAIRE

    Jeuring, J.T.; Swierstra, D.

    1994-01-01

    This paper discusses bottom-up grammar analysis problems such as te EMPTY problem and the FIRST problem. It defines a general class of bottom-up grammar analysis problems, and from this definition it derives a functional program for performing bottom-up grammar analysis. The derivation is purely calculational, using theorems from lattice therory, the Bird-Meertens calculus, and laws for list-comprehensions. Sufficient conditions guaranteeing the existence of a solution emerge as a byproduct o...

  7. A top-down / bottom-up approach for multi-actors and multi-criteria assessment of mining projects for sustainable development. Application on Arlit Uranium mines (Niger); Une demarche Top-Down / Bottom-Up pour l'evaluation en termes multicriteres et multi-acteurs des projets miniers dans l'optique du developpement durable. Application sur les mines d'Uranium d'Arlit (Niger)

    Energy Technology Data Exchange (ETDEWEB)

    Chamaret, A

    2007-06-15

    This thesis aims to appraise the relevance of using an hybrid top-down / bottom-up approach to evaluate mining projects in the perspective of sustainable development. With the advent of corporate social responsibility and sustainable development concepts, new social expectations have appeared towards companies that go beyond a sole requirement of profit earning capacity. If companies do not answer to these expectations, they risk to lose their social legitimacy. Traditionally associated with social, environmental, economical and political impacts and risks, mining activity is particularly concerned by these new issues. Whereas mineral resources needs have never been so high, mining companies are now expected to limit their negative effects and to take into account their different audiences' expectations in order to define, together, the terms of their social license to operate. Considering the diversity of issues, scales, actors and contexts, the challenge is real and necessitates tools to better understand issues and to structure dialogues. Based on the Uranium mines of Arlit (Niger) case study, this work shows that associating participatory approaches to structuration tools and literature propositions, appears as an efficient formula to better organize issues diversity and to build a structured dialogue between mining companies and their stakeholders. First Part aims to present the theoretical, institutional and sectorial contexts of the thesis. Second Part exposes work and results of the evaluation carried out in Niger. And, Third Part, shows the conclusions that can be derived from this work and presents a proposal for an evaluation framework, potentially applicable to other mining sites. (author)

  8. Making the results of bottom-up energy savings comparable

    Directory of Open Access Journals (Sweden)

    Moser Simon

    2012-01-01

    Full Text Available The Energy Service Directive (ESD has pushed forward the issue of energy savings calculations without clarifying the methodological basis. Savings achieved in the Member States are calculated with rather non-transparent and hardly comparable Bottom-up (BU methods. This paper develops the idea of parallel evaluation tracks separating the Member States’ issue of ESD verification and comparable savings calculations. Comparability is ensured by developing a standardised BU calculation kernel for different energy efficiency improvement (EEI actions which simultaneously depicts the different calculation options in a structured way (e.g. baseline definition, system boundaries, double counting. Due to the heterogeneity of BU calculations the approach requires a central database where Member States feed in input data on BU actions according to a predefined structure. The paper demonstrates the proposed approach including a concrete example of application.

  9. New, national bottom-up estimate for tree-based biological ...

    Science.gov (United States)

    Nitrogen is a limiting nutrient in many ecosystems, but is also a chief pollutant from human activity. Quantifying human impacts on the nitrogen cycle and investigating natural ecosystem nitrogen cycling both require an understanding of the magnitude of nitrogen inputs from biological nitrogen fixation (BNF). A bottom-up approach to estimating BNF—scaling rates up from measurements to broader scales—is attractive because it is rooted in actual BNF measurements. However, bottom-up approaches have been hindered by scaling difficulties, and a recent top-down approach suggested that the previous bottom-up estimate was much too large. Here, we used a bottom-up approach for tree-based BNF, overcoming scaling difficulties with the systematic, immense (>70,000 N-fixing trees) Forest Inventory and Analysis (FIA) database. We employed two approaches to estimate species-specific BNF rates: published ecosystem-scale rates (kg N ha-1 yr-1) and published estimates of the percent of N derived from the atmosphere (%Ndfa) combined with FIA-derived growth rates. Species-specific rates can vary for a variety of reasons, so for each approach we examined how different assumptions influenced our results. Specifically, we allowed BNF rates to vary with stand age, N-fixer density, and canopy position (since N-fixation is known to require substantial light).Our estimates from this bottom-up technique are several orders of magnitude lower than previous estimates indicating

  10. Bottom-Up or Top-Down: English as a Foreign Language Vocabulary Instruction for Chinese University Students

    Science.gov (United States)

    Moskovsky, Christo; Jiang, Guowu; Libert, Alan; Fagan, Seamus

    2015-01-01

    Whereas there has been some research on the role of bottom-up and top-down processing in the learning of a second or foreign language, very little attention has been given to bottom-up and top-down instructional approaches to language teaching. The research reported here used a quasi-experimental design to assess the relative effectiveness of two…

  11. Iodine versus Bromine Functionalization for Bottom-Up Graphene Nanoribbon Growth

    DEFF Research Database (Denmark)

    Bronner, Christopher; Marangoni, Tomas; Rizzo, Daniel J.

    2017-01-01

    Deterministic bottom-up approaches for synthesizing atomically well-defined graphene nanoribbons (GNRs) largely rely on the surface-catalyzed activation of selected labile bonds in a molecular precursor followed by step-growth polymerization and cyclodehydrogenation. While the majority of success......Deterministic bottom-up approaches for synthesizing atomically well-defined graphene nanoribbons (GNRs) largely rely on the surface-catalyzed activation of selected labile bonds in a molecular precursor followed by step-growth polymerization and cyclodehydrogenation. While the majority...

  12. Bringing justice to the poor, bottom-up legal development cooperation

    NARCIS (Netherlands)

    van Rooij, B.

    2012-01-01

    In the last decade bottom-up approaches to legal development cooperation have become increasingly popular. Examples are reform ideas and programmes using concepts such as ‘access to justice’ and ‘legal empowerment.’ These approaches share a common concern that legal interventions should benefit the

  13. Hydrophobic Interaction Chromatography for Bottom-Up Proteomics Analysis of Single Proteins and Protein Complexes.

    Science.gov (United States)

    Rackiewicz, Michal; Große-Hovest, Ludger; Alpert, Andrew J; Zarei, Mostafa; Dengjel, Jörn

    2017-06-02

    Hydrophobic interaction chromatography (HIC) is a robust standard analytical method to purify proteins while preserving their biological activity. It is widely used to study post-translational modifications of proteins and drug-protein interactions. In the current manuscript we employed HIC to separate proteins, followed by bottom-up LC-MS/MS experiments. We used this approach to fractionate antibody species followed by comprehensive peptide mapping as well as to study protein complexes in human cells. HIC-reversed-phase chromatography (RPC)-mass spectrometry (MS) is a powerful alternative to fractionate proteins for bottom-up proteomics experiments making use of their distinct hydrophobic properties.

  14. When endogenous spatial attention improves conscious perception: effects of alerting and bottom-up activation.

    Science.gov (United States)

    Botta, Fabiano; Lupiáñez, Juan; Chica, Ana B

    2014-01-01

    Recent studies have consistently demonstrated that conscious perception interacts with exogenous attentional orienting, but it can be dissociated from endogenous attentional orienting (Chica Lasaponara, et al., 2011; Wyart & Tallon-Baudry, 2008). It has been hypothesized that enhanced conscious processing at exogenously attended locations results from a synergistic action of spatial orienting, bottom-up activation, and phasic alerting induced by the abrupt onset of the exogenous cue (Chica, Lasaponara, et al., 2011). Instead, as endogenous cues need more time to be interpreted, the phasic alerting they produce may have dissipated when the target appears. Furthermore, endogenous cues presumably elicit a weak bottom-up activation at the cued location. Consistent with these hypotheses, we observed that endogenous attention modulated conscious perception, but only when phasic alerting or bottom-up activation was increased. Results are discussed in the context of recent theoretical models of consciousness (Dehaene, Changeux, Naccache, Sackur, & Sergent, 2006). Copyright © 2013 Elsevier Inc. All rights reserved.

  15. A plea for Global Health Action bottom-up

    Directory of Open Access Journals (Sweden)

    Ulrich Laaser

    2016-10-01

    Full Text Available This opinion piece focuses on global health action by hands-on bottom-up practice: Initiation of an organizational framework and securing financial efficiency are – however - essential, both clearly a domain of well trained public health professionals. Examples of action are cited in the four main areas of global threats: planetary climate change, global divides and inequity, global insecurity and violent conflicts, global instability and financial crises. In conclusion a stable health systems policy framework would greatly enhance success. However, such organisational framework dries out if not linked to public debates channelling fresh thoughts and controversial proposals: the structural stabilisation is essential but has to serve not to dominate bottom-up activities. In other words a horizontal management is required, a balanced equilibrium between bottom-up initiative and top-down support. Last not least rewarding voluntary and charity work by public acknowledgement is essential.

  16. A Plea for Global Health Action Bottom-Up.

    Science.gov (United States)

    Laaser, Ulrich; Dorey, Stephen; Nurse, Joanna

    2016-01-01

    This opinion piece focuses on global health action by hands-on bottom-up practice: initiation of an organizational framework and securing financial efficiency are - however - essential, both clearly a domain of well-trained public health professionals. Examples of action are cited in the four main areas of global threats: planetary climate change, global divides and inequity, global insecurity and violent conflicts, and global instability and financial crises. In conclusion, a stable health systems policy framework would greatly enhance success. However, such organizational framework dries out if not linked to public debates channeling fresh thoughts and controversial proposals: the structural stabilization is essential but has to serve not to dominate bottom-up activities. In other words, a horizontal management is required, a balanced equilibrium between bottom-up initiative and top-down support. Last but not least, rewarding voluntary and charity work by public acknowledgment is essential.

  17. Managing Bottom up Strategizing : Collective Sensemaking of Strategic Issues in a Dutch Bank

    NARCIS (Netherlands)

    van der Steen, Martijn

    2017-01-01

    This paper discusses a bottom-up approach to strategizing in two member banks of a Dutch cooperative bank. In both banks, through a collective process of sensemaking, organisational participants evaluated their day-to-day experiences in order to identify strategic issues. The potential benefits of

  18. Enhanced Photon Extraction from a Nanowire Quantum Dot Using a Bottom-Up Photonic Shell

    DEFF Research Database (Denmark)

    Jeannin, Mathieu; Cremel, Thibault; Häyrynen, Teppo

    2017-01-01

    Semiconductor nanowires offer the possibility to grow high-quality quantum-dot heterostructures, and, in particular, CdSe quantum dots inserted in ZnSe nanowires have demonstrated the ability to emit single photons up to room temperature. In this paper, we demonstrate a bottom-up approach...

  19. Planning from the bottom up : Democratic decentralisation in action

    NARCIS (Netherlands)

    Pal, A.

    2010-01-01

    This research highlights the gap between the official rhetoric and the political reality of democratic decentralisation and bottom-up planning using an indepth study of the metropolitan planning process in Kolkata, India. The key question that I address here is: how do elected officials at different

  20. The Interplay of Top-Down and Bottom-Up

    DEFF Research Database (Denmark)

    Winkler, Till; Brown, Carol V.; Ozturk, Pinar

    2014-01-01

    The exchange of patient health information across different organizations involved in healthcare delivery has potential benefits for a wide range of stakeholders. However, many governments in Europe and in the U.S. have, despite both top-down and bottom-up initiatives, experienced major barriers ...

  1. An integrated top-down and bottom-up strategy for characterization protein isoforms and modifications

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Si; Tolic, Nikola; Tian, Zhixin; Robinson, Errol W.; Pasa-Tolic, Ljiljana

    2011-04-15

    Bottom-up and top-down strategies are two commonly used methods for mass spectrometry (MS) based protein identification; each method has its own advantages and disadvantages. In this chapter, we describe an integrated top-down and bottom-up approach facilitated by concurrent liquid chromatography-mass spectrometry (LC-MS) analysis and fraction collection for comprehensive high-throughput intact protein profiling. The approach employs a high resolution reversed phase (RP) LC separation coupled with LC eluent fraction collection and concurrent on-line MS with a high field (12 Tesla) Fourier-transform ion cyclotron resonance (FTICR) mass spectrometer. Protein elusion profiles and tentative modified protein identification are made using detected intact protein mass in conjunction with bottom-up protein identifications from the enzymatic digestion and analysis of corresponding LC fractions. Specific proteins of biological interest are incorporated into a target ion list for subsequent off-line gas-phase fragmentation that uses an aliquot of the original collected LC fraction, an aliquot of which was also used for bottom-up analysis.

  2. Top-Down Beta Enhances Bottom-Up Gamma.

    Science.gov (United States)

    Richter, Craig G; Thompson, William H; Bosman, Conrado A; Fries, Pascal

    2017-07-12

    Several recent studies have demonstrated that the bottom-up signaling of a visual stimulus is subserved by interareal gamma-band synchronization, whereas top-down influences are mediated by alpha-beta band synchronization. These processes may implement top-down control of stimulus processing if top-down and bottom-up mediating rhythms are coupled via cross-frequency interaction. To test this possibility, we investigated Granger-causal influences among awake macaque primary visual area V1, higher visual area V4, and parietal control area 7a during attentional task performance. Top-down 7a-to-V1 beta-band influences enhanced visually driven V1-to-V4 gamma-band influences. This enhancement was spatially specific and largest when beta-band activity preceded gamma-band activity by ∼0.1 s, suggesting a causal effect of top-down processes on bottom-up processes. We propose that this cross-frequency interaction mechanistically subserves the attentional control of stimulus selection. SIGNIFICANCE STATEMENT Contemporary research indicates that the alpha-beta frequency band underlies top-down control, whereas the gamma-band mediates bottom-up stimulus processing. This arrangement inspires an attractive hypothesis, which posits that top-down beta-band influences directly modulate bottom-up gamma band influences via cross-frequency interaction. We evaluate this hypothesis determining that beta-band top-down influences from parietal area 7a to visual area V1 are correlated with bottom-up gamma frequency influences from V1 to area V4, in a spatially specific manner, and that this correlation is maximal when top-down activity precedes bottom-up activity. These results show that for top-down processes such as spatial attention, elevated top-down beta-band influences directly enhance feedforward stimulus-induced gamma-band processing, leading to enhancement of the selected stimulus. Copyright © 2017 Richter, Thompson et al.

  3. Learning dynamics by theoretical tools of game theory. Comment on "Move me, astonish me...delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates" by M. Pelowski et al.

    Science.gov (United States)

    Burini, Diletta; De Lillo, Silvana

    2017-07-01

    The VIMAP model presented in the survey [5] aims at analyzing the processes that can occur in the human perception in the front of an artwork. Such a model combines the bottom-up (artwork derived) processes with the top-down mechanisms which describe how individuals adapt or change their own art processing experience. The cognitive flow consists of seven stages connected to five outcomes, which account for all the main ways of responding to art. Moreover this model can also identify the specific regions of the brain that are posited to be main centers of the processes that may coincide with the proposed cognitive checks.

  4. Bottom-up effects on attention capture and choice

    DEFF Research Database (Denmark)

    Peschel, Anne; Orquin, Jacob Lund; Mueller Loose, Simone

    Attention processes and decision making are accepted to be closely linked together because only information that is attended to can be incorporated in the decision process. Little is known however, to which extent bottom-up processes of attention affect stimulus selection and therefore...... the information available to form a decision. Does changing one visual cue in the stimulus set affect attention towards this cue and what does that mean for the choice outcome? To address this, we conducted a combined eye tracking and choice experiment in a consumer choice setting with visual shelf simulations...... of different product categories. Surface size and visual saliency of a product label were manipulated to determine bottom-up effects on attention and choice. Results show a strong and significant increase in attention in terms of fixation likelihood towards product labels which are larger and more visually...

  5. On studying protein phosphorylation patterns using bottom-up LC-MS/MS: the case of human alpha-casein

    DEFF Research Database (Denmark)

    Kjeldsen, Frank; Savitski, Mikhail M; Nielsen, Michael L

    2007-01-01

    Most proteomics studies involving mapping post-translational modifications, such as the phosphorylation of serine and threonine, are performed today using the 'bottom-up' approach. This approach involves enzymatic cleavage of proteins, most often by trypsin, with subsequent nano-LC-MS/MS. The occ......Most proteomics studies involving mapping post-translational modifications, such as the phosphorylation of serine and threonine, are performed today using the 'bottom-up' approach. This approach involves enzymatic cleavage of proteins, most often by trypsin, with subsequent nano......-LC-MS/MS. The occupancy rates of phosphosites in proteins may differ by orders of magnitude, and thus the occupancy rate must be reported for each occupied phosphosite. To highlight potential pitfalls in quantifying the occupancy rates, alpha(s1)-casein from human milk was selected as a model molecule representing...... moderately phosphorylated proteins. For this purpose, human milk from one Caucasian woman in the eighth month of lactation was used. The phosphorylation level of caseins is believed to have major implications for the formation of micelles that are involved in delivering valuable calcium phosphate and other...

  6. A balance of bottom-up and top-down in linking climate policies

    Science.gov (United States)

    Green, Jessica F.; Sterner, Thomas; Wagner, Gernot

    2014-12-01

    Top-down climate negotiations embodied by the Kyoto Protocol have all but stalled, chiefly because of disagreements over targets and objections to financial transfers. To avoid those problems, many have shifted their focus to linkage of bottom-up climate policies such as regional carbon markets. This approach is appealing, but we identify four obstacles to successful linkage: different levels of ambition; competing domestic policy objectives; objections to financial transfers; and the difficulty of close regulatory coordination. Even with a more decentralized approach, overcoming the 'global warming gridlock' of the intergovernmental negotiations will require close international coordination. We demonstrate how a balance of bottom-up and top-down elements can create a path toward an effective global climate architecture.

  7. The generation of myricetin-nicotinamide nanococrystals by top down and bottom up technologies.

    Science.gov (United States)

    Liu, Mingyu; Hong, Chao; Li, Guowen; Ma, Ping; Xie, Yan

    2016-09-30

    Myricetin-nicotinamide (MYR-NIC) nanococrystal preparation methods were developed and optimized using both top down and bottom up approaches. The grinding (top down) method successfully achieved nanococrystals, but there were some micrometer range particles and aggregation. The key consideration of the grinding technology was to control the milling time to determine a balance between the particle size and distribution. In contrast, a modified bottom up approach based on a solution method in conjunction with sonochemistry resulted in a uniform MYR-NIC nanococrystal that was confirmed by powder x-ray diffraction, scanning electron microscopy, dynamic light scattering, and differential scanning calorimeter, and the particle dissolution rate and amount were significantly greater than that of MYR-NIC cocrystal. Notably, this was a simple method without the addition of any non-solvent. We anticipate our findings will provide some guidance for future nanococrystal preparation as well as its application in both chemical and pharmaceutical area.

  8. The forgotten artist: Why to consider intentions and interaction in a model of aesthetic experience. Comment on "Move me, astonish me... delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates" by Matthew Pelowski et al.

    Science.gov (United States)

    Brattico, Elvira; Brattico, Pauli; Vuust, Peter

    2017-07-01

    In their target article published in this journal issue, Pelowski et al. [1] address the question of how humans experience, and respond to, visual art. They propose a multi-layered model of the representations and processes involved in assessing visual art objects that, furthermore, involves both bottom-up and top-down elements. Their model provides predictions for seven different outcomes of human aesthetic experience, based on few distinct features (schema congruence, self-relevance, and coping necessity), and connects the underlying processing stages to ;specific correlates of the brain; (a similar attempt was previously done for music by [2-4]). In doing this, the model aims to account for the (often profound) experience of an individual viewer in front of an art object.

  9. A constraint-based bottom-up counterpart to definite clause grammars

    DEFF Research Database (Denmark)

    Christiansen, Henning

    2004-01-01

    A new grammar formalism, CHR Grammars (CHRG), is proposed that provides a constraint-solving approach to language analysis, built on top of the programming language of Constraint Handling Rules in the same way as Definite Clause Grammars (DCG) on Prolog. CHRG works bottom-up and adds the followin......, integrity constraints, operators a la assumption grammars, and to incorporate other constraint solvers. (iv)~Context-sensitive rules that apply for disambiguation, coordination in natural language and tagger-like rules....

  10. A Bottom up Initiative: Meditation & Mindfulness 'Eastern' Practices in the "Western" Academia

    DEFF Research Database (Denmark)

    Singla, Rashmi

    a case of bottom up initiative, where the students themselves have demanded inclusion of non- conventional psychosocial interventions illustrated by meditation and mindfulness as Eastern psychological practices, thus filling the gap related to the existential, spiritual approaches. The western...... course dynamic developed and the evaluation is to be delineated in the paper. In addition, both pedagogical psychological aspects and long term consequences of such initiatives are discussed. Lastly implications for future integration of knowledge in a globalised world are perspectivised through...

  11. On the interactions between top-down anticipation and bottom-up regression

    Directory of Open Access Journals (Sweden)

    Jun Tani

    2007-11-01

    Full Text Available This paper discusses the importance of anticipation and regression in modeling cognitive behavior. The meanings of these cognitive functions are explained by describing our proposed neural network model which has been implemented on a set of cognitive robotics experiments. The reviews of these experiments suggest that the essences of embodied cognition may reside in the phenomena of the break-down between the top-down anticipation and the bottom-up regression and in its recovery process.

  12. Bottom-up capacity building for data providers in RITMARE

    Science.gov (United States)

    Pepe, Monica; Basoni, Anna; Bastianini, Mauro; Fugazza, Cristiano; Menegon, Stefano; Oggioni, Alessandro; Pavesi, Fabio; Sarretta, Alessandro; Carrara, Paola

    2014-05-01

    RITMARE is a Flagship Project by the Italian Ministry of Research, coordinated by the National Research Council (CNR). It aims at the interdisciplinary integration of Italian marine research. Sub-project 7 shall create an interoperable infrastructure for the project, capable of interconnecting the whole community of researchers involved. It will allow coordinating and sharing of data, processes, and information produced by the other sub-projects [1]. Spatial Data Infrastructures (SDIs) allow for interoperable sharing among heterogeneous, distributed spatial content providers. The INSPIRE Directive [2] regulates the development of a pan-european SDI despite the great variety of national approaches in managing spatial data. However, six years after its adoption, its growth is still hampered by technological, cultural, and methodological gaps. In particular, in the research sector, actors may not be prone to comply with INSPIRE (or feel not compelled to) because they are too concentrated on domain-specific activities or hindered by technological issues. Indeed, the available technologies and tools for enabling standard-based discovery and access services are far from being user-friendly and requires time-consuming activities, such as metadata creation. Moreover, the INSPIRE implementation guidelines do not accommodate an essential component in environmental research, that is, in situ observations. In order to overcome most of the aforementioned issues and to enable researchers to actively give their contribution in the creation of the project infrastructure, a bottom-up approach has been adopted: a software suite has been developed, called Starter Kit, which is offered to research data production units, so that they can become autonomous, independent nodes of data provision. The Starter Kit enables the provision of geospatial resources, either geodata (e.g., maps and layers) or observations pulled from sensors, which are made accessible according to the OGC standards

  13. Agricultural ammonia emissions in China: reconciling bottom-up and top-down estimates

    Directory of Open Access Journals (Sweden)

    L. Zhang

    2018-01-01

    Full Text Available Current estimates of agricultural ammonia (NH3 emissions in China differ by more than a factor of 2, hindering our understanding of their environmental consequences. Here we apply both bottom-up statistical and top-down inversion methods to quantify NH3 emissions from agriculture in China for the year 2008. We first assimilate satellite observations of NH3 column concentration from the Tropospheric Emission Spectrometer (TES using the GEOS-Chem adjoint model to optimize Chinese anthropogenic NH3 emissions at the 1∕2°  ×  2∕3° horizontal resolution for March–October 2008. Optimized emissions show a strong summer peak, with emissions about 50 % higher in summer than spring and fall, which is underestimated in current bottom-up NH3 emission estimates. To reconcile the latter with the top-down results, we revisit the processes of agricultural NH3 emissions and develop an improved bottom-up inventory of Chinese NH3 emissions from fertilizer application and livestock waste at the 1∕2°  ×  2∕3° resolution. Our bottom-up emission inventory includes more detailed information on crop-specific fertilizer application practices and better accounts for meteorological modulation of NH3 emission factors in China. We find that annual anthropogenic NH3 emissions are 11.7 Tg for 2008, with 5.05 Tg from fertilizer application and 5.31 Tg from livestock waste. The two sources together account for 88 % of total anthropogenic NH3 emissions in China. Our bottom-up emission estimates also show a distinct seasonality peaking in summer, consistent with top-down results from the satellite-based inversion. Further evaluations using surface network measurements show that the model driven by our bottom-up emissions reproduces the observed spatial and seasonal variations of NH3 gas concentrations and ammonium (NH4+ wet deposition fluxes over China well, providing additional credibility to the improvements we have made to our

  14. A Bottom-up Approach to Data Annotation in Neurophysiology.

    Science.gov (United States)

    Grewe, Jan; Wachtler, Thomas; Benda, Jan

    2011-01-01

    Metadata providing information about the stimulus, data acquisition, and experimental conditions are indispensable for the analysis and management of experimental data within a lab. However, only rarely are metadata available in a structured, comprehensive, and machine-readable form. This poses a severe problem for finding and retrieving data, both in the laboratory and on the various emerging public data bases. Here, we propose a simple format, the "open metaData Markup Language" (odML), for collecting and exchanging metadata in an automated, computer-based fashion. In odML arbitrary metadata information is stored as extended key-value pairs in a hierarchical structure. Central to odML is a clear separation of format and content, i.e., neither keys nor values are defined by the format. This makes odML flexible enough for storing all available metadata instantly without the necessity to submit new keys to an ontology or controlled terminology. Common standard keys can be defined in odML-terminologies for guaranteeing interoperability. We started to define such terminologies for neurophysiological data, but aim at a community driven extension and refinement of the proposed definitions. By customized terminologies that map to these standard terminologies, metadata can be named and organized as required or preferred without softening the standard. Together with the respective libraries provided for common programming languages, the odML format can be integrated into the laboratory workflow, facilitating automated collection of metadata information where it becomes available. The flexibility of odML also encourages a community driven collection and definition of terms used for annotating data in the neurosciences.

  15. Contextualised ICT4D: a Bottom-Up Approach

    DEFF Research Database (Denmark)

    Lund, Henrik Hautop; Sutinen, Erkki

    2010-01-01

    The term ICT4D refers to the opportunities of Information and Communication Technology (ICT) as an agent of development. Much of the research in the field is based on evaluating the feasibility of existing technologies, mostly of Western or Asian origin, in the context of developing countries. In...

  16. Preparedness plan for flood: a bottom up approach | Shariff | Journal ...

    African Journals Online (AJOL)

    Floods have caused major disasters around the world and these include Malaysia which is inevitable. However, we can be prepared by taking the lessons from the previous flood disasters. This paper attempts to highlight preparedness plan executed by the community i.e. six months before the expected flood in December ...

  17. Pivots - A Bottom-Up Approach to Enhance Resilience

    Science.gov (United States)

    2015-12-01

    public policy. These two sharp minds, securely placed above generous hearts, gave me the attention that Sara Lawrence-Lightfoot rightly describes as a...federal guidance and as a laboratory with very practical applications on disaster recovery for practitioners. For instance, a dissertation by Blake ...108 Blake O. Escudier, “Louisiana Small Business Owner Stated Problems during Recovery from Hurricane Katrina: Outsider

  18. On viewer motivation, unit of analysis, and the VIMAP. Comment on "Move me, astonish me ... delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates" by Matthew Pelowski et al.

    Science.gov (United States)

    Tinio, Pablo P. L.

    2017-07-01

    The Vienna Integrated Model of Art Perception (VIMAP; [5]) is the most comprehensive model of the art experience today. The model incorporates bottom-up and top-down cognitive processes and accounts for different outcomes of the art experience, such as aesthetic evaluations, emotions, and physiological and neurological responses to art. In their presentation of the model, Pelowski et al. also present hypotheses that are amenable to empirical testing. These features make the VIMAP an ambitious model that attempts to explain how meaningful, complex, and profound aspects of the art experience come about, which is a significant extension of previous models of the art experience (e.g., [1-3,10]), and which gives the VIMAP good explanatory power.

  19. ICT-ENABLED BOTTOM-UP ARCHITECTURAL DESIGN

    Directory of Open Access Journals (Sweden)

    Burak Pak

    2016-04-01

    Full Text Available This paper aims at discussing the potentials of bottom-up design practices in relation to the latest developments in Information and Communication Technologies (ICT by making an in-depth review of inaugural cases. The first part of the study involves a literature study and the elaboration of basic strategies from the case study. The second part reframes the existing ICT tools and strategies and elaborates on their potentials to support the modes of participation performed in these cases. As a result, by distilling the created knowledge, the study reveals the potentials of novel modes of ICT-enabled design participation which exploit a set of collective action tools to support sustainable ways of self-organization and bottom-up design. The final part explains the relevance of these with solid examples and presents a hypothetical case for future implementation. The paper concludes with a brief reflection on the implications of the findings for the future of architectural design education.

  20. Bottom-up laboratory testing of the DKIST Visible Broadband Imager (VBI)

    Science.gov (United States)

    Ferayorni, Andrew; Beard, Andrew; Cole, Wes; Gregory, Scott; Wöeger, Friedrich

    2016-08-01

    The Daniel K. Inouye Solar Telescope (DKIST) is a 4-meter solar observatory under construction at Haleakala, Hawaii [1]. The Visible Broadband Imager (VBI) is a first light instrument that will record images at the highest possible spatial and temporal resolution of the DKIST at a number of scientifically important wavelengths [2]. The VBI is a pathfinder for DKIST instrumentation and a test bed for developing processes and procedures in the areas of unit, systems integration, and user acceptance testing. These test procedures have been developed and repeatedly executed during VBI construction in the lab as part of a "test early and test often" philosophy aimed at identifying and resolving issues early thus saving cost during integration test and commissioning on summit. The VBI team recently completed a bottom up end-to-end system test of the instrument in the lab that allowed the instrument's functionality, performance, and usability to be validated against documented system requirements. The bottom up testing approach includes four levels of testing, each introducing another layer in the control hierarchy that is tested before moving to the next level. First the instrument mechanisms are tested for positioning accuracy and repeatability using a laboratory position-sensing detector (PSD). Second the real-time motion controls are used to drive the mechanisms to verify speed and timing synchronization requirements are being met. Next the high-level software is introduced and the instrument is driven through a series of end-to-end tests that exercise the mechanisms, cameras, and simulated data processing. Finally, user acceptance testing is performed on operational and engineering use cases through the use of the instrument engineering graphical user interface (GUI). In this paper we present the VBI bottom up test plan, procedures, example test cases and tools used, as well as results from test execution in the laboratory. We will also discuss the benefits realized

  1. Integrating Top-down and Bottom-up Cybersecurity Guidance using XML.

    Science.gov (United States)

    Lubell, Joshua

    2016-08-01

    This paper describes a markup-based approach for synthesizing disparate information sources and discusses a software implementation of the approach. The implementation makes it easier for people to use two complementary, but differently structured, guidance specifications together: the (top-down) Cybersecurity Framework and the (bottom-up) National Institute of Standards and Technology Special Publication 800-53 security control catalog. An example scenario demonstrates how the software implementation can help a security professional select the appropriate safeguards for restricting unauthorized access to an Industrial Control System. The implementation and example show the benefits of this approach and suggest its potential application to disciplines other than cybersecurity.

  2. Integrating Top-down and Bottom-up Cybersecurity Guidance using XML

    Science.gov (United States)

    Lubell, Joshua

    2016-01-01

    This paper describes a markup-based approach for synthesizing disparate information sources and discusses a software implementation of the approach. The implementation makes it easier for people to use two complementary, but differently structured, guidance specifications together: the (top-down) Cybersecurity Framework and the (bottom-up) National Institute of Standards and Technology Special Publication 800-53 security control catalog. An example scenario demonstrates how the software implementation can help a security professional select the appropriate safeguards for restricting unauthorized access to an Industrial Control System. The implementation and example show the benefits of this approach and suggest its potential application to disciplines other than cybersecurity. PMID:27795810

  3. BitCube: A Bottom-Up Cubing Engineering

    Science.gov (United States)

    Ferro, Alfredo; Giugno, Rosalba; Puglisi, Piera Laura; Pulvirenti, Alfredo

    Enhancing on line analytical processing through efficient cube computation plays a key role in Data Warehouse management. Hashing, grouping and mining techniques are commonly used to improve cube pre-computation. BitCube, a fast cubing method which uses bitmaps as inverted indexes for grouping, is presented. It horizontally partitions data according to the values of one dimension and for each resulting fragment it performs grouping following bottom-up criteria. BitCube allows also partial materialization based on iceberg conditions to treat large datasets for which a full cube pre-computation is too expensive. Space requirement of bitmaps is optimized by applying an adaption of the WAH compression technique. Experimental analysis, on both synthetic and real datasets, shows that BitCube outperforms previous algorithms for full cube computation and results comparable on iceberg cubing.

  4. Uncertainty quantification for radiation measurements: Bottom-up error variance estimation using calibration information

    International Nuclear Information System (INIS)

    Burr, T.; Croft, S.; Krieger, T.; Martin, K.; Norman, C.; Walsh, S.

    2016-01-01

    One example of top-down uncertainty quantification (UQ) involves comparing two or more measurements on each of multiple items. One example of bottom-up UQ expresses a measurement result as a function of one or more input variables that have associated errors, such as a measured count rate, which individually (or collectively) can be evaluated for impact on the uncertainty in the resulting measured value. In practice, it is often found that top-down UQ exhibits larger error variances than bottom-up UQ, because some error sources are present in the fielded assay methods used in top-down UQ that are not present (or not recognized) in the assay studies used in bottom-up UQ. One would like better consistency between the two approaches in order to claim understanding of the measurement process. The purpose of this paper is to refine bottom-up uncertainty estimation by using calibration information so that if there are no unknown error sources, the refined bottom-up uncertainty estimate will agree with the top-down uncertainty estimate to within a specified tolerance. Then, in practice, if the top-down uncertainty estimate is larger than the refined bottom-up uncertainty estimate by more than the specified tolerance, there must be omitted sources of error beyond those predicted from calibration uncertainty. The paper develops a refined bottom-up uncertainty approach for four cases of simple linear calibration: (1) inverse regression with negligible error in predictors, (2) inverse regression with non-negligible error in predictors, (3) classical regression followed by inversion with negligible error in predictors, and (4) classical regression followed by inversion with non-negligible errors in predictors. Our illustrations are of general interest, but are drawn from our experience with nuclear material assay by non-destructive assay. The main example we use is gamma spectroscopy that applies the enrichment meter principle. Previous papers that ignore error in predictors

  5. Intercomparison of a 'Bottom-up' and 'Top-down' Modeling Paradigm for estimating carbon and latent heat fluxes over a variety of vegetative regimes across the U.S., Agricultural and Forest Meteorology

    Science.gov (United States)

    Biophysical models intended for routine applications at a range of scales should attempt to balance the competing demands of generality and simplicity and be capable of realistically simulating the response of CO2 and energy fluxes to environmental and physiological forcings. At the same time they m...

  6. Top-down and bottom-up definitions of human failure events in human reliability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Boring, Ronald Laurids [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-10-01

    In the probabilistic risk assessments (PRAs) used in the nuclear industry, human failure events (HFEs) are determined as a subset of hardware failures, namely those hardware failures that could be triggered by human action or inaction. This approach is top-down, starting with hardware faults and deducing human contributions to those faults. Elsewhere, more traditionally human factors driven approaches would tend to look at opportunities for human errors first in a task analysis and then identify which of those errors is risk significant. The intersection of top-down and bottom-up approaches to defining HFEs has not been carefully studied. Ideally, both approaches should arrive at the same set of HFEs. This question is crucial, however, as human reliability analysis (HRA) methods are generalized to new domains like oil and gas. The HFEs used in nuclear PRAs tend to be top-down—defined as a subset of the PRA—whereas the HFEs used in petroleum quantitative risk assessments (QRAs) often tend to be bottom-up—derived from a task analysis conducted by human factors experts. The marriage of these approaches is necessary in order to ensure that HRA methods developed for top-down HFEs are also sufficient for bottom-up applications.

  7. The potential of LCM to mainstream bottom-up eco-innovation and alternative thinking

    DEFF Research Database (Denmark)

    De Rosa, Michele; Ghose, Agneta

    2015-01-01

    . For this reason, under the LCM framework, a number of bottom-up eco innovations and non-traditional approaches can be categorized, arising often in difficult economic context. However, it is not because of LCM that alternative solutions were found in these cases, but due to necessity. The potential of LCM and its...... level. The first example is Can Decreix in Cerbere, a social experiment that intend to demonstrate how the entire society can be managed in an alternative way, cleaner and more equitable, consuming less and sharing more. Activities involve frugal technologies, agroecology, educational workshops...

  8. Peat accumulation in kettle holes: bottom up or top down?

    Directory of Open Access Journals (Sweden)

    G. Gaudig

    2006-12-01

    Full Text Available Rapid peat formation in kettle hole-shaped basins may take place either a by peat forming downwards (top down from a floating mat under stable water level conditions (terrestrialisation, or b by peat forming upwards (bottom up as humus colloids seal off the basin, causing the water level to rise progressively (“kettle hole mire mechanism”. The latter mechanism has hardly been considered in the international literature. The floating-mat mechanism must lead to concave peat isochrones throughout the basin, whereas the kettle hole mire mechanism will yield surface-parallel isochrones. Peat isochrones were studied in three mires occupying kettle hole-shaped basins in north-eastern Germany by comparing pollen samples from the mineral soil–peat interface at different distances from the centre of each mire with the pollen assemblage profile of a central peat core. All three mires appeared to have largely surface-parallel isochrones and must have developed by the kettle hole mire mechanism. In one mire, this mechanism alternated and took place in combination with terrestrialisation following karst subsidence. The fact that evidence of the kettle hole mire mechanism was found at all of the sites investigated indicates that it may be a common peat forming mechanism in kettle hole-shaped basins worldwide.

  9. Bottom-Up Synthesis and Sensor Applications of Biomimetic Nanostructures

    Directory of Open Access Journals (Sweden)

    Li Wang

    2016-01-01

    Full Text Available The combination of nanotechnology, biology, and bioengineering greatly improved the developments of nanomaterials with unique functions and properties. Biomolecules as the nanoscale building blocks play very important roles for the final formation of functional nanostructures. Many kinds of novel nanostructures have been created by using the bioinspired self-assembly and subsequent binding with various nanoparticles. In this review, we summarized the studies on the fabrications and sensor applications of biomimetic nanostructures. The strategies for creating different bottom-up nanostructures by using biomolecules like DNA, protein, peptide, and virus, as well as microorganisms like bacteria and plant leaf are introduced. In addition, the potential applications of the synthesized biomimetic nanostructures for colorimetry, fluorescence, surface plasmon resonance, surface-enhanced Raman scattering, electrical resistance, electrochemistry, and quartz crystal microbalance sensors are presented. This review will promote the understanding of relationships between biomolecules/microorganisms and functional nanomaterials in one way, and in another way it will guide the design and synthesis of biomimetic nanomaterials with unique properties in the future.

  10. Bottom Up Project Cost and Risk Modeling, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm along with its partners HRP Systems, End-to-End Analytics, and ARES Corporation (unfunded in Phase I), propose to develop a new solution for detailed data...

  11. Bottom-Up Design of a Copper-Ruthenium Nanoparticulate Catalyst for Low-Temperature Ammonia Oxidation

    DEFF Research Database (Denmark)

    Chakraborty, Debasish; Damsgaard, Christian Danvad; Silva, Hugo José Lopes

    2017-01-01

    A novel nanoparticulate catalyst of copper (Cu) and ruthenium (Ru) was designed for low-temperature ammonia oxidation at near-stoichiometric mixtures using a bottom-up approach. A synergistic effect of the two metals was found. An optimum CuRu catalyst presents a reaction rate threefold higher than...

  12. Visual anticipation biases conscious decision making but not bottom-up visual processing.

    Science.gov (United States)

    Mathews, Zenon; Cetnarski, Ryszard; Verschure, Paul F M J

    2014-01-01

    Prediction plays a key role in control of attention but it is not clear which aspects of prediction are most prominent in conscious experience. An evolving view on the brain is that it can be seen as a prediction machine that optimizes its ability to predict states of the world and the self through the top-down propagation of predictions and the bottom-up presentation of prediction errors. There are competing views though on whether prediction or prediction errors dominate the formation of conscious experience. Yet, the dynamic effects of prediction on perception, decision making and consciousness have been difficult to assess and to model. We propose a novel mathematical framework and a psychophysical paradigm that allows us to assess both the hierarchical structuring of perceptual consciousness, its content and the impact of predictions and/or errors on conscious experience, attention and decision-making. Using a displacement detection task combined with reverse correlation, we reveal signatures of the usage of prediction at three different levels of perceptual processing: bottom-up fast saccades, top-down driven slow saccades and consciousnes decisions. Our results suggest that the brain employs multiple parallel mechanism at different levels of perceptual processing in order to shape effective sensory consciousness within a predicted perceptual scene. We further observe that bottom-up sensory and top-down predictive processes can be dissociated through cognitive load. We propose a probabilistic data association model from dynamical systems theory to model the predictive multi-scale bias in perceptual processing that we observe and its role in the formation of conscious experience. We propose that these results support the hypothesis that consciousness provides a time-delayed description of a task that is used to prospectively optimize real time control structures, rather than being engaged in the real-time control of behavior itself.

  13. Visual anticipation biases conscious perception but not bottom-up visual processing

    Directory of Open Access Journals (Sweden)

    Paul F.M.J. Verschure

    2015-01-01

    Full Text Available Theories of consciousness can be grouped with respect to their stance on embodiment, sensori-motor contingencies, prediction and integration. In this list prediction plays a key role and it is not clear which aspects of prediction are most prominent in the conscious scene. An evolving view on the brain is that it can be seen as a prediction machine that optimizes its ability to predict states of the world and the self through the top-down propagation of predictions and the bottom-up presentation of prediction errors. There are competing views though on whether prediction or prediction errors dominate the conscious scene. Yet, due to the lack of efficient indirect measures, the dynamic effects of prediction on perception, decision making and consciousness have been difficult to assess and to model. We propose a novel mathematical framework and psychophysical paradigm that allows us to assess both the hierarchical structuring of perceptual consciousness, its content and the impact of predictions and / or errors on the conscious scene. Using a displacement detection task combined with reverse correlation we reveal signatures of the usage of prediction at three different levels of perception: bottom-up early saccades, top-down driven late saccades and conscious decisions. Our results suggest that the brain employs multiple parallel mechanisms at different levels of information processing to restrict the sensory field using predictions. We observe that cognitive load has a quantifiable effect on this dissociation of the bottom-up sensory and top-down predictive processes. We propose a probabilistic data association model from dynamical systems theory to model this predictive bias in different information processing levels.

  14. Bottom-up assembly of salivary gland microtissues for assessing myoepithelial cell function.

    Science.gov (United States)

    Ozdemir, Tugba; Srinivasan, Padma Pradeepa; Zakheim, Daniel R; Harrington, Daniel A; Witt, Robert L; Farach-Carson, Mary C; Jia, Xinqiao; Pradhan-Bhatt, Swati

    2017-10-01

    Myoepithelial cells are flat, stellate cells present in exocrine tissues including the salivary glands. While myoepithelial cells have been studied extensively in mammary and lacrimal gland tissues, less is known of the function of myoepithelial cells derived from human salivary glands. Several groups have isolated tumorigenic myoepithelial cells from cancer specimens, however, only one report has demonstrated isolation of normal human salivary myoepithelial cells needed for use in salivary gland tissue engineering applications. Establishing a functional organoid model consisting of myoepithelial and secretory acinar cells is therefore necessary for understanding the coordinated action of these two cell types in unidirectional fluid secretion. Here, we developed a bottom-up approach for generating salivary gland microtissues using primary human salivary myoepithelial cells (hSMECs) and stem/progenitor cells (hS/PCs) isolated from normal salivary gland tissues. Phenotypic characterization of isolated hSMECs confirmed that a myoepithelial cell phenotype consistent with that from other exocrine tissues was maintained over multiple passages of culture. Additionally, hSMECs secreted basement membrane proteins, expressed adrenergic and cholinergic neurotransmitter receptors, and released intracellular calcium [Ca 2+ i ] in response to parasympathetic agonists. In a collagen I contractility assay, activation of contractile machinery was observed in isolated hSMECs treated with parasympathetic agonists. Recombination of hSMECs with assembled hS/PC spheroids in a microwell system was used to create microtissues resembling secretory complexes of the salivary gland. We conclude that the engineered salivary gland microtissue complexes provide a physiologically relevant model for both mechanistic studies and as a building block for the successful engineering of the salivary gland for restoration of salivary function in patients suffering from hyposalivation. Copyright © 2017

  15. Bottom-Up Gazetteers: Learning from the Implicit Semantics of Geotags

    Science.gov (United States)

    Keßler, Carsten; Maué, Patrick; Heuer, Jan Torben; Bartoschek, Thomas

    As directories of named places, gazetteers link the names to geographic footprints and place types. Most existing gazetteers are managed strictly top-down: entries can only be added or changed by the responsible toponymic authority. The covered vocabulary is therefore often limited to an administrative view on places, using only official place names. In this paper, we propose a bottom-up approach for gazetteer building based on geotagged photos harvested from the web. We discuss the building blocks of a geotag and how they relate to each other to formally define the notion of a geotag. Based on this formalization, we introduce an extraction process for gazetteer entries that captures the emergent semantics of collections of geotagged photos and provides a group-cognitive perspective on named places. Using an experimental setup based on clustering and filtering algorithms, we demonstrate how to identify place names and assign adequate geographic footprints. The results for three different place names (Soho, Camino de Santiago and Kilimanjaro), representing different geographic feature types, are evaluated and compared to the results obtained from traditional gazetteers. Finally, we sketch how our approach can be combined with other (for example, linguistic) approaches and discuss how such a bottom-up gazetteer can complement existing gazetteers.

  16. Bottom-up communication. Identifying opportunities and limitations through an exploratory field-based evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, C.; Irvine, K.N. [Institute of Energy and Sustainable Development, De Montfort University, Leicester, LE1 9BH (United Kingdom)

    2013-02-15

    Communication to promote behaviours like energy saving can use significant resources. What is less clear is the comparative value of different approaches available to communicators. While it is generally agreed that 'bottom-up' approaches, where individuals are actively involved rather than passive, are preferable to 'top-down' authority-led projects, there is a dearth of evidence that verifies why this should be. Additionally, while the literature has examined the mechanics of the different approaches, there has been less attention paid to the associated psychological implications. This paper reports on an exploratory comparative study that examined the effects of six distinct communication activities. The activities used different communication approaches, some participative and others more top-down informational. Two theories, from behavioural studies and communication, were used to identify key variables for consideration in this field-based evaluation. The evaluation aimed to assess not just which activity might be most successful, as this has limited generalisability, but to also gain insight into what psychological impacts might contribute to success. Analysis found support for the general hypothesis that bottom-up approaches have more impact on behaviour change than top-down. The study also identified that, in this instance, the difference in reported behaviour across the activities related partly to the extent to which intentions to change behaviour were implemented. One possible explanation for the difference in reported behaviour change across the activities is that a bottom-up approach may offer a supportive environment where participants can discuss progress with like-minded individuals. A further possible explanation is that despite controlling for intention at an individual level, the pre-existence of strong intentions may have an effect on group success. These suggestive findings point toward the critical need for additional and larger-scale studies

  17. Reconciling Top-Down and Bottom-Up Estimates of Oil and Gas Methane Emissions in the Barnett Shale

    Science.gov (United States)

    Hamburg, S.

    2015-12-01

    Top-down approaches that use aircraft, tower, or satellite-based measurements of well-mixed air to quantify regional methane emissions have typically estimated higher emissions from the natural gas supply chain when compared to bottom-up inventories. A coordinated research campaign in October 2013 used simultaneous top-down and bottom-up approaches to quantify total and fossil methane emissions in the Barnett Shale region of Texas. Research teams have published individual results including aircraft mass-balance estimates of regional emissions and a bottom-up, 25-county region spatially-resolved inventory. This work synthesizes data from the campaign to directly compare top-down and bottom-up estimates. A new analytical approach uses statistical estimators to integrate facility emission rate distributions from unbiased and targeted high emission site datasets, which more rigorously incorporates the fat-tail of skewed distributions to estimate regional emissions of well pads, compressor stations, and processing plants. The updated spatially-resolved inventory was used to estimate total and fossil methane emissions from spatial domains that match seven individual aircraft mass balance flights. Source apportionment of top-down emissions between fossil and biogenic methane was corroborated with two independent analyses of methane and ethane ratios. Reconciling top-down and bottom-up estimates of fossil methane emissions leads to more accurate assessment of natural gas supply chain emission rates and the relative contribution of high emission sites. These results increase our confidence in our understanding of the climate impacts of natural gas relative to more carbon-intensive fossil fuels and the potential effectiveness of mitigation strategies.

  18. Assessing the Gap Between Top-down and Bottom-up Measured Methane Emissions in Indianapolis, IN.

    Science.gov (United States)

    Prasad, K.; Lamb, B. K.; Cambaliza, M. O. L.; Shepson, P. B.; Stirm, B. H.; Salmon, O. E.; Lavoie, T. N.; Lauvaux, T.; Ferrara, T.; Howard, T.; Edburg, S. L.; Whetstone, J. R.

    2014-12-01

    Releases of methane (CH4) from the natural gas supply chain in the United States account for approximately 30% of the total US CH4 emissions. However, there continues to be large questions regarding the accuracy of current emission inventories for methane emissions from natural gas usage. In this paper, we describe results from top-down and bottom-up measurements of methane emissions from the large isolated city of Indianapolis. The top-down results are based on aircraft mass balance and tower based inverse modeling methods, while the bottom-up results are based on direct component sampling at metering and regulating stations, surface enclosure measurements of surveyed pipeline leaks, and tracer/modeling methods for other urban sources. Mobile mapping of methane urban concentrations was also used to identify significant sources and to show an urban-wide low level enhancement of methane levels. The residual difference between top-down and bottom-up measured emissions is large and cannot be fully explained in terms of the uncertainties in top-down and bottom-up emission measurements and estimates. Thus, the residual appears to be, at least partly, attributed to a significant wide-spread diffusive source. Analyses are included to estimate the size and nature of this diffusive source.

  19. Bottom-up production of meta-atoms for optical magnetism in visible and NIR light

    Science.gov (United States)

    Barois, Philippe; Ponsinet, Virginie; Baron, Alexandre; Richetti, Philippe

    2018-02-01

    Many unusual optical properties of metamaterials arise from the magnetic response of engineered structures of sub-wavelength size (meta-atoms) exposed to light. The top-down approach whereby engineered nanostructure of well-defined morphology are engraved on a surface proved to be successful for the generation of strong optical magnetism. It faces however the limitations of high cost and small active area in visible light where nanometre resolution is needed. The bottom-up approach whereby the fabrication metamaterials of large volume or large area results from the combination of nanochemitry and self-assembly techniques may constitute a cost-effective alternative. This approach nevertheless requires the large-scale production of functional building-blocks (meta-atoms) bearing a strong magnetic optical response. We propose in this paper a few tracks that lead to the large scale synthesis of magnetic metamaterials operating in visible or near IR light.

  20. Nanomanufacturing of gold nanoparticle superstructures from the "bottom-up"

    Science.gov (United States)

    Rao, Tingling

    Gold nanoparticles that can generate surface plasmons under appropriate conditions have attracted significant interest for their potential in optics, photonics, data storage and biological sensors. Developing high fidelity fabrication methods that yield gold nanoparticles with well-defined size, shape, composition and self-assembly allows manipulation of surface plasmonic properties for novel applications as well as revealing new aspects of the underlying science. This dissertation demonstrates multiple techniques that describe cost-effective bottom-up" fabrication methods that yield gold nano-superstructures. In my initial work, I outline the solution conditions for fabricating Janus nanoparticles composed of one gold nanoparticle per micelle. Poly(ethylene oxide)-b-polystyrene (PEO-b-PS) was synthesized and processed into spherical micelles, which served as the template to induce gold nanoparticles growth within the PEO corona in situ. Organic-inorganic hybrid nanoparticle formation was controlled kinetically by manipulating the concentration of both the micelle and reducing agent (HEPES). We also found that under certain condition, PEO-b-PS yielded micelles with pearl-like morphology, which possessed concentrated PEO domains at the interface between two adjacent PS cores. Careful manipulation of reaction conditions afforded gold nanoparticles that grew from the core-shell interface to form 1-dimensional (1-D) periodical gold nanoparticle chains. Based on similar principles, gold-gold dimers were synthesized by growing a second gold nanoparticle from a gold nanoparticle template surface-functionalized with PEO ligands. Gold dimers fabricated with this method exhibited strong enhancement properties via surface-enhanced Raman scattering (SERS). Instead of kinetic control, the number of newly grown gold nanoparticles on each particle template heavily relied on the PEO density on the nanoparticle template. As the size of the particle template increased from 10 nm to

  1. Bottom-Up Meets Top-Down: Patchy Hybrid Nonwovens as an Efficient Catalysis Platform.

    Science.gov (United States)

    Schöbel, Judith; Burgard, Matthias; Hils, Christian; Dersch, Roland; Dulle, Martin; Volk, Kirsten; Karg, Matthias; Greiner, Andreas; Schmalz, Holger

    2017-01-02

    Heterogeneous catalysis with supported nanoparticles (NPs) is a highly active field of research. However, the efficient stabilization of NPs without deteriorating their catalytic activity is challenging. By combining top-down (coaxial electrospinning) and bottom-up (crystallization-driven self-assembly) approaches, we prepared patchy nonwovens with functional, nanometer-sized patches on the surface. These patches can selectively bind and efficiently stabilize gold nanoparticles (AuNPs). The use of these AuNP-loaded patchy nonwovens in the alcoholysis of dimethylphenylsilane led to full conversion under comparably mild conditions and in short reaction times. The absence of gold leaching or a slowing down of the reaction even after ten subsequent cycles manifests the excellent reusability of this catalyst system. The flexibility of the presented approach allows for easy transfer to other nonwoven supports and catalytically active NPs, which promises broad applicability. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. The Comparative Effect of Top-down Processing and Bottom-up Processing through TBLT on Extrovert and Introvert EFL

    Directory of Open Access Journals (Sweden)

    Pezhman Nourzad Haradasht

    2013-09-01

    Full Text Available This research seeks to examine the effect of two models of reading comprehension, namely top-down and bottom-up processing, on the reading comprehension of extrovert and introvert EFL learners’ reading comprehension. To do this, 120 learners out of a total number of 170 intermediate learners being educated at Iran Mehr English Language School were selected all taking a PET (Preliminary English Test first for homogenization prior to the study. They also answered the Eysenck Personality Inventory (EPI which in turn categorized them into two subgroups within each reading models consisting of introverts and extroverts. All in all, there were four subgroups: 30 introverts and 30 extroverts undergoing the top-down processing treatment, and 30 introverts and 30 extroverts experiencing the bottom-up processing treatment. The aforementioned PET was administered as the post test of the study after each group was exposed to the treatment for 18 sessions in six weeks. After the instructions finished, the mean scores of all four groups on this post test were computed and a two-way ANOVA was run to test all the four hypotheses raise in this study. the results showed that while learners generally benefitted more from the bottom-up processing setting compared  to the top-down processing one, the extrovert group was better off receiving top-down instruction. Furthermore, introverts outperformed extroverts in bottom-up group; yet between the two personalities subgroups in the top-down setting no difference was seen. A predictable pattern of benefitting from teaching procedures could not be drawn for introverts as in both top-down and bottom-up settings, they benefitted more than extroverts.

  3. Reconciling Basin-Scale Top-Down and Bottom-Up Methane Emission Measurements for Onshore Oil and Gas Development: Cooperative Research and Development Final Report, CRADA Number CRD-14-572

    Energy Technology Data Exchange (ETDEWEB)

    Heath, Garvin A. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-12-04

    The overall objective of the Research Partnership to Secure Energy for America (RPSEA)-funded research project is to develop independent estimates of methane emissions using top-down and bottom-up measurement approaches and then to compare the estimates, including consideration of uncertainty. Such approaches will be applied at two scales: basin and facility. At facility scale, multiple methods will be used to measure methane emissions of the whole facility (controlled dual tracer and single tracer releases, aircraft-based mass balance and Gaussian back-trajectory), which are considered top-down approaches. The bottom-up approach will sum emissions from identified point sources measured using appropriate source-level measurement techniques (e.g., high-flow meters). At basin scale, the top-down estimate will come from boundary layer airborne measurements upwind and downwind of the basin, using a regional mass balance model plus approaches to separate atmospheric methane emissions attributed to the oil and gas sector. The bottom-up estimate will result from statistical modeling (also known as scaling up) of measurements made at selected facilities, with gaps filled through measurements and other estimates based on other studies. The relative comparison of the bottom-up and top-down estimates made at both scales will help improve understanding of the accuracy of the tested measurement and modeling approaches. The subject of this CRADA is NREL's contribution to the overall project. This project resulted from winning a competitive solicitation no. RPSEA RFP2012UN001, proposal no. 12122-95, which is the basis for the overall project. This Joint Work Statement (JWS) details the contributions of NREL and Colorado School of Mines (CSM) in performance of the CRADA effort.

  4. Large solar angle and see-saw mechanism: a bottom-up perspective

    Energy Technology Data Exchange (ETDEWEB)

    Lavignac, Stephane E-mail: lavignac@spht.saclay.cea.fr; Masina, Isabella E-mail: masina@spht.saclay.cea.fr; Savoy, Carlos A. E-mail: savoy@spht.saclay.cea.fr

    2002-06-24

    In addition to the well established large atmospheric angle, a large solar angle is probably present in the leptonic sector. In the context of the see-saw and by means of a bottom-up approach, we explore which patterns for the Dirac and Majorana right-handed mass matrices provide two large mixings in a robust way and with the minimal amount of tuning. Three favorite patterns emerge, which have a suggestive physical interpretation in terms of the role played by right-handed neutrinos: in both solar and atmospheric sectors, either a single or a pseudo-Dirac pair of right-handed neutrinos dominates. Each pattern gives rise to specific relations among the neutrino mixing angles and mass differences, which lead to testable constraints on U{sub e3}. The connection with the rate of LFV charged lepton decays is also addressed.

  5. Bottom-Up Nanofabrication of Supported Noble Metal Alloy Nanoparticle Arrays for Plasmonics

    DEFF Research Database (Denmark)

    Nugroho, Ferry A. A.; Iandolo, Beniamino; Wagner, Jakob Birkedal

    2016-01-01

    Mixing different elements at the nanoscale to obtain alloy nanostructures with fine-tuned physical and chemical properties offers appealing opportunities for nanotechnology and nanoscience. However, despite widespread successful application of alloy nanoparticles made by colloidal synthesis...... in heterogeneous catalysis, nanoalloy systems have been used very rarely in solid-state devices and nanoplasmonics-related applications. One reason is that such applications require integration in arrays on a surface with compelling demands on nanoparticle arrangement, uniformity in surface coverage......, and optimization of the surface density. These cannot be fulfilled even using state-of-the-art self -assembly strategies of colloids. As a solution, we present here a generic bottom-up nanolithography-compatible fabrication approach for large-area arrays of alloy nanoparticles on surfaces. To illustrate...

  6. Bottom-Up Cost Analysis of a High Concentration PV Module; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, K.; Woodhouse, M.; Lee, H.; Smestad, G.

    2015-04-13

    We present a bottom-up model of III-V multi-junction cells, as well as a high concentration PV (HCPV) module. We calculate $0.65/Wp(DC) manufacturing costs for our model HCPV module design with today’s capabilities, and find that reducing cell costs and increasing module efficiency offer the promising pathways for future cost reductions. Cell costs could be significantly reduced via an increase in manufacturing scale, substrate reuse, and improved manufacturing yields. We also identify several other significant drivers of HCPV module costs, including the Fresnel lens primary optic, module housing, thermal management, and the receiver board. These costs could potentially be lowered by employing innovative module designs.

  7. Achieving social-ecological fit through bottom-up collaborative governance: an empirical investigation

    Directory of Open Access Journals (Sweden)

    Angela M. Guerrero

    2015-12-01

    Full Text Available Significant benefits can arise from collaborative forms of governance that foster self-organization and flexibility. Likewise, governance systems that fit with the extent and complexity of the system under management are considered essential to our ability to solve environmental problems. However, from an empirical perspective the fundamental question of whether self-organized (bottom-up collaborative forms of governance are able to accomplish adequate fit is unresolved. We used new theory and methodological approaches underpinned by interdisciplinary network analysis to address this gap by investigating three governance challenges that relate to the problem of fit: shared management of ecological resources, management of interconnected ecological resources, and cross-scale management. We first identified a set of social-ecological network configurations that represent the hypothesized ways in which collaborative arrangements can contribute to addressing these challenges. Using social and ecological data from a large-scale biodiversity conservation initiative in Australia, we empirically determined how well the observed patterns of stakeholder interactions reflect these network configurations. We found that stakeholders collaborate to manage individual parcels of native vegetation, but not for the management of interconnected parcels. In addition, our data show that the collaborative arrangements enable management across different scales (local, regional, supraregional. Our study provides empirical support for the ability of collaborative forms of governance to address the problem of fit, but also suggests that in some cases the establishment of bottom-up collaborative arrangements would likely benefit from specific guidance to facilitate the establishment of collaborations that better align with the ways ecological resources are interconnected across the landscape. In our case study region, this would improve the capacity of stakeholders to

  8. A Comparative Prospective Study of Two Different Treatment Sequences i.e. Bottom Up-Inside Out and Topdown-Outside in, in the Treatment of Panfacial Fractures.

    Science.gov (United States)

    Degala, Saikrishna; Sundar, S Shyam; Mamata, K S

    2015-12-01

    To compare the sequence bottom-up inside-out with top-down outside-in, in the treatment of pan facial fractures and to evaluate the outcome of these approaches. The data from 11 patients with panfacial fracture are prospectively analysed. Five cases are treated with bottom-up approach and six patients with top-down approach. There were 11 male patients (six in top-down approach and five in bottom-up approach), ranging in age from 24 to 50 years. All injuries were result of RTA (n = 11, 100 %). Final treatment outcome was excellent in 3 (50 %), 1 (16 %) good and 2 (32 %) cases were fair in topdown approach, 3 (60 %) excellent and 2 (40 %) fair in bottom up approach with contingency coefficient value (P reconstruction of the remaining. Choice of the bottom-up inside-out or top-down outside-in sequence should be according to the pattern of fractures and preference of the surgeon. However, further controlled clinical trials, comparative studies with a larger sample size would be better to evaluate the final clinical outcome of individual techniques.

  9. Adding Gestalt to the picture. Comment on "Move me, astonish me…" delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates; by Matthew Pelowski et al.

    Science.gov (United States)

    Wagemans, Johan

    2017-07-01

    Matthew Pelowski and his colleagues from the Helmut Leder lab [17] have made a remarkable contribution to the field of art perception by reviewing the extensive and varied literature (+300 references) on all the factors involved, from a coherent, synthetic perspective-The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP). VIMAP builds on earlier attempts from the same group to provide a comprehensive theoretical framework, but it is much wider in scope and richer in the number of levels and topics covered under its umbrella. It is particularly strong in its discussion of the different psychological processes that lead to a wide range of possible responses to art-from mundane, superficial reactions to more profound responses characterized as moving, disturbing, and transformative. By including physiological, emotional, and evaluative factors, the model is able to address truly unique, even intimate responses to art such as awe, chills, thrills, and the experience of the sublime. The unique way in which this rich set of possible responses to art is achieved is through a series of five mandatory consecutive processing steps (each with their own typical duration), followed by two conditional additional steps (which take more time). Three processing checks along this cascade lead to three more or less spontaneous outcomes (consuming ones (see their Fig. 1 for an excellent overview). I have no doubt that VIMAP will inspire a whole generation of scientists investigating perception and appreciation of art, testing specific hypotheses derived from this framework for decades to come.

  10. Bottom-Up Energy Analysis System (BUENAS). An international appliance efficiency policy tool

    Energy Technology Data Exchange (ETDEWEB)

    McNeil, M.A.; Letschert, V.E.; De la Rue du Can, S.; Ke, Jing [Lawrence Berkeley National Laboratory LBNL, 1 Cyclotron Rd, Berkeley, CA (United States)

    2013-02-15

    The Bottom-Up Energy Analysis System (BUENAS) calculates potential energy and greenhouse gas emission impacts of efficiency policies for lighting, heating, ventilation, and air conditioning, appliances, and industrial equipment through 2030. The model includes 16 end use categories and covers 11 individual countries plus the European Union. BUENAS is a bottom-up stock accounting model that predicts energy consumption for each type of equipment in each country according to engineering-based estimates of annual unit energy consumption, scaled by projections of equipment stock. Energy demand in each scenario is determined by equipment stock, usage, intensity, and efficiency. When available, BUENAS uses sales forecasts taken from country studies to project equipment stock. Otherwise, BUENAS uses an econometric model of household appliance uptake developed by the authors. Once the business as usual scenario is established, a high-efficiency policy scenario is constructed that includes an improvement in the efficiency of equipment installed in 2015 or later. Policy case efficiency targets represent current 'best practice' and include standards already established in a major economy or well-defined levels known to enjoy a significant market share in a major economy. BUENAS calculates energy savings according to the difference in energy demand in the two scenarios. Greenhouse gas emission mitigation is then calculated using a forecast of electricity carbon factor. We find that mitigation of 1075 mt annual CO2 emissions is possible by 2030 from adopting current best practices of appliance efficiency policies. This represents a 17 % reduction in emissions in the business as usual case in that year.

  11. Bottom-up effects of a no-take zone on endangered penguin demographics.

    Science.gov (United States)

    Sherley, Richard B; Winker, Henning; Altwegg, Res; van der Lingen, Carl D; Votier, Stephen C; Crawford, Robert J M

    2015-07-01

    Marine no-take zones can have positive impacts for target species and are increasingly important management tools. However, whether they indirectly benefit higher order predators remains unclear. The endangered African penguin (Spheniscus demersus) depends on commercially exploited forage fish. We examined how chick survival responded to an experimental 3-year fishery closure around Robben Island, South Africa, controlling for variation in prey biomass and fishery catches. Chick survival increased by 18% when the closure was initiated, which alone led to a predicted 27% higher population compared with continued fishing. However, the modelled population continued to decline, probably because of high adult mortality linked to poor prey availability over larger spatial scales. Our results illustrate that small no-take zones can have bottom-up benefits for highly mobile marine predators, but are only one component of holistic, ecosystem-based management regimes. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  12. Platform Dependencies in Bottom-up Hydrogen/Deuterium Exchange Mass Spectrometry*

    Science.gov (United States)

    Burns, Kyle M.; Rey, Martial; Baker, Charles A. H.; Schriemer, David C.

    2013-01-01

    Hydrogen-deuterium exchange mass spectrometry is an important method for protein structure-function analysis. The bottom-up approach uses protein digestion to localize deuteration to higher resolution, and the essential measurement involves centroid mass determinations on a very large set of peptides. In the course of evaluating systems for various projects, we established two (HDX-MS) platforms that consisted of a FT-MS and a high-resolution QTOF mass spectrometer, each with matched front-end fluidic systems. Digests of proteins spanning a 20–110 kDa range were deuterated to equilibrium, and figures-of-merit for a typical bottom-up (HDX-MS) experiment were compared for each platform. The Orbitrap Velos identified 64% more peptides than the 5600 QTOF, with a 42% overlap between the two systems, independent of protein size. Precision in deuterium measurements using the Orbitrap marginally exceeded that of the QTOF, depending on the Orbitrap resolution setting. However, the unique nature of FT-MS data generates situations where deuteration measurements can be inaccurate, because of destructive interference arising from mismatches in elemental mass defects. This is shown through the analysis of the peptides common to both platforms, where deuteration values can be as low as 35% of the expected values, depending on FT-MS resolution, peptide length and charge state. These findings are supported by simulations of Orbitrap transients, and highlight that caution should be exercised in deriving centroid mass values from FT transients that do not support baseline separation of the full isotopic composition. PMID:23197788

  13. Platform dependencies in bottom-up hydrogen/deuterium exchange mass spectrometry.

    Science.gov (United States)

    Burns, Kyle M; Rey, Martial; Baker, Charles A H; Schriemer, David C

    2013-02-01

    Hydrogen-deuterium exchange mass spectrometry is an important method for protein structure-function analysis. The bottom-up approach uses protein digestion to localize deuteration to higher resolution, and the essential measurement involves centroid mass determinations on a very large set of peptides. In the course of evaluating systems for various projects, we established two (HDX-MS) platforms that consisted of a FT-MS and a high-resolution QTOF mass spectrometer, each with matched front-end fluidic systems. Digests of proteins spanning a 20-110 kDa range were deuterated to equilibrium, and figures-of-merit for a typical bottom-up (HDX-MS) experiment were compared for each platform. The Orbitrap Velos identified 64% more peptides than the 5600 QTOF, with a 42% overlap between the two systems, independent of protein size. Precision in deuterium measurements using the Orbitrap marginally exceeded that of the QTOF, depending on the Orbitrap resolution setting. However, the unique nature of FT-MS data generates situations where deuteration measurements can be inaccurate, because of destructive interference arising from mismatches in elemental mass defects. This is shown through the analysis of the peptides common to both platforms, where deuteration values can be as low as 35% of the expected values, depending on FT-MS resolution, peptide length and charge state. These findings are supported by simulations of Orbitrap transients, and highlight that caution should be exercised in deriving centroid mass values from FT transients that do not support baseline separation of the full isotopic composition.

  14. Preferential effect of isoflurane on top-down vs. bottom-up pathways in sensory cortex.

    Science.gov (United States)

    Raz, Aeyal; Grady, Sean M; Krause, Bryan M; Uhlrich, Daniel J; Manning, Karen A; Banks, Matthew I

    2014-01-01

    The mechanism of loss of consciousness (LOC) under anesthesia is unknown. Because consciousness depends on activity in the cortico-thalamic network, anesthetic actions on this network are likely critical for LOC. Competing theories stress the importance of anesthetic actions on bottom-up "core" thalamo-cortical (TC) vs. top-down cortico-cortical (CC) and matrix TC connections. We tested these models using laminar recordings in rat auditory cortex in vivo and murine brain slices. We selectively activated bottom-up vs. top-down afferent pathways using sensory stimuli in vivo and electrical stimulation in brain slices, and compared effects of isoflurane on responses evoked via the two pathways. Auditory stimuli in vivo and core TC afferent stimulation in brain slices evoked short latency current sinks in middle layers, consistent with activation of core TC afferents. By contrast, visual stimuli in vivo and stimulation of CC and matrix TC afferents in brain slices evoked responses mainly in superficial and deep layers, consistent with projection patterns of top-down afferents that carry visual information to auditory cortex. Responses to auditory stimuli in vivo and core TC afferents in brain slices were significantly less affected by isoflurane compared to responses triggered by visual stimuli in vivo and CC/matrix TC afferents in slices. At a just-hypnotic dose in vivo, auditory responses were enhanced by isoflurane, whereas visual responses were dramatically reduced. At a comparable concentration in slices, isoflurane suppressed both core TC and CC/matrix TC responses, but the effect on the latter responses was far greater than on core TC responses, indicating that at least part of the differential effects observed in vivo were due to local actions of isoflurane in auditory cortex. These data support a model in which disruption of top-down connectivity contributes to anesthesia-induced LOC, and have implications for understanding the neural basis of consciousness.

  15. Hacking Health: Bottom-up Innovation for Healthcare

    Directory of Open Access Journals (Sweden)

    Jeeshan Chowdhury

    2012-07-01

    Full Text Available Healthcare is not sustainable and still functions with outdated technology (e.g., pagers, paper records. Top-down approaches by governments and corporations have failed to deliver digital technologies to modernize healthcare. Disruptive innovation must come from the ground up by bridging the gap between front-line health experts and innovators in the latest web and mobile technology. Hacking Health is a hackathon that is focused on social innovation more than technical innovation. Our approach to improve healthcare is to pair technological innovators with healthcare experts to build realistic, human-centric solutions to front-line healthcare problems.

  16. Generalised bottom-up holography and walking technicolour

    DEFF Research Database (Denmark)

    D. Dietrich, Dennis; Kouvaris, Christoforos

    2009-01-01

    In extradimensional holographic approaches the flavour symmetry is gauged in the bulk, that is, treated as a local symmetry. Imposing such a local symmetry admits fewer terms coupling the (axial) vectors and (pseudo)scalars than if a global symmetry is imposed. The latter is the case in standard ...

  17. Mapping practices of project management – merging top-down and bottom-up perspectives

    DEFF Research Database (Denmark)

    Thuesen, Christian

    2015-01-01

    This paper presents a new methodology for studying different accounts of project management practices based on network mapping and analysis. Drawing upon network mapping and visualization as an analytical strategy top-down and bottom-up accounts of project management practice are analysed...... and compared. The analysis initially reveals a substantial difference between the top-down and bottom-up accounts of practice. Furthermore it identifies a soft side of project management that is central in the bottom-up account but absent from the top-down. Finally, the study shows that network mapping...... is a promising strategy for visualizing and analysing different accounts of project management practices....

  18. Simple rules describe bottom-up and top-down control in food webs with alternative energy pathways.

    Science.gov (United States)

    Wollrab, Sabine; Diehl, Sebastian; De Roos, André M

    2012-09-01

    Many human influences on the world's ecosystems have their largest direct impacts at either the top or the bottom of the food web. To predict their ecosystem-wide consequences we must understand how these impacts propagate. A long-standing, but so far elusive, problem in this endeavour is how to reduce food web complexity to a mathematically tractable, but empirically relevant system. Simplification to main energy channels linking primary producers to top consumers has been recently advocated. Following this approach, we propose a general framework for the analysis of bottom-up and top-down forcing of ecosystems by reducing food webs to two energy pathways originating from a limiting resource shared by competing guilds of primary producers (e.g. edible vs. defended plants). Exploring dynamical models of such webs we find that their equilibrium responses to nutrient enrichment and top consumer harvesting are determined by only two easily measurable topological properties: the lengths of the component food chains (odd-odd, odd-even, or even-even) and presence vs. absence of a generalist top consumer reconnecting the two pathways (yielding looped vs. branched webs). Many results generalise to other looped or branched web structures and the model can be easily adapted to include a detrital pathway. © 2012 Blackwell Publishing Ltd/CNRS.

  19. Bottom-Up Assembly and Applications of Photonic Materials

    Directory of Open Access Journals (Sweden)

    Hanbin Zheng

    2016-05-01

    Full Text Available The assembly of colloidal building-blocks is an efficient, inexpensive and flexible approach for the fabrication of a wide variety of photonic materials with designed shapes and large areas. In this review, the various assembly routes to the fabrication of colloidal crystals and their post-assembly modifications to the production of photonic materials are first described. Then, the emerging applications of the colloidal photonic structures in various fields such as biological and chemical sensing, anti-reflection, photovoltaics, and light extraction are summarized.

  20. Flipped Top-Down is Systematic Bottom-Up

    NARCIS (Netherlands)

    Zaytsev, V.; Sturm, A.; Clark, T.

    2016-01-01

    The paper presents an experience report in course design for a versatile group of computer science students where their needs were surfaced and met by the combination of strict top-down exposure to course material and the flipped classroom model of lecturing.

  1. Bottom-Up Energy Analysis System - Methodology and Results

    Energy Technology Data Exchange (ETDEWEB)

    McNeil, Michael A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Letschert, Virginie E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stephane, de la Rue du Can [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ke, Jing [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-06-15

    The main objective of the development of BUENAS is to provide a global model with sufficient detail and accuracy for technical assessment of policy measures such as energy efficiency standards and labeling (EES&L) programs. In most countries where energy efficiency policies exist, the initial emphasis is on household appliances and lighting. Often, equipment used in commercial buildings, particularly heating, air conditioning and ventilation (HVAC) is also covered by EES&L programs. In the industrial sector, standards and labeling generally covers electric motors and distribution transformers, although a few more types of industrial equipment are covered by some programs, and there is a trend toward including more of them. In order to make a comprehensive estimate of the total potential impacts, development of the model prioritized coverage of as many end uses commonly targeted by EES&L programs as possible, for as many countries as possible.

  2. Bottom-up and top-down effects on plant communities

    DEFF Research Database (Denmark)

    Souza, Lara; Zelikova, Tamara Jane; Sanders, Nate

    2016-01-01

    Top-down effects of herbivores and bottom-up effects of nutrients shape productivity and diversity across ecosystems, yet their single and combined effects on spatial and temporal beta diversity is unknown. We established a field experiment in which the abundance of insect herbivores (top...... herbivores did not alter plant richness (α diversity) yet consistently promoted Shannon's evenness, relative to plots where insect herbivores were present. Further, insect herbivores promoted spatial-temporal β diversity. Overall, we found that the relative importance of top-down and bottom-up controls......-down) and soil nitrogen (bottom-up) were manipulated over six years in an existing old-field community. We tracked plant α and β diversity - within plot richness and among plot biodiversity- and aboveground net primary productivity (ANPP) over the course of the experiment. We found that bottom-up factors...

  3. Bottom-up regulation of capelin, a keystone forage species.

    Science.gov (United States)

    Buren, Alejandro D; Koen-Alonso, Mariano; Pepin, Pierre; Mowbray, Fran; Nakashima, Brian; Stenson, Garry; Ollerhead, Neil; Montevecchi, William A

    2014-01-01

    The Northwest Atlantic marine ecosystem off Newfoundland and Labrador, Canada, has been commercially exploited for centuries. Although periodic declines in various important commercial fish stocks have been observed in this ecosystem, the most drastic changes took place in the early 1990s when the ecosystem structure changed abruptly and has not returned to its previous configuration. In the Northwest Atlantic, food web dynamics are determined largely by capelin (Mallotus villosus), the focal forage species which links primary and secondary producers with the higher trophic levels. Notwithstanding the importance of capelin, the factors that influence its population dynamics have remained elusive. We found that a regime shift and ocean climate, acting via food availability, have discernible impacts on the regulation of this population. Capelin biomass and timing of spawning were well explained by a regime shift and seasonal sea ice dynamics, a key determinant of the pelagic spring bloom. Our findings are important for the development of ecosystem approaches to fisheries management and raise questions on the potential impacts of climate change on the structure and productivity of this marine ecosystem.

  4. Bottom-up synthetic biology: modular design for making artificial platelets

    Science.gov (United States)

    Majumder, Sagardip; Liu, Allen P.

    2018-01-01

    Engineering artificial cells to mimic one or multiple fundamental cell biological functions is an emerging area of synthetic biology. Reconstituting functional modules from biological components in vitro is a challenging yet an important essence of bottom-up synthetic biology. Here we describe the concept of building artificial platelets using bottom-up synthetic biology and the four functional modules that together could enable such an ambitious effort.

  5. Bottom-up priority setting revised. A second evaluation of an institutional intervention in a Swedish health care organisation.

    Science.gov (United States)

    Waldau, Susanne

    2015-09-01

    Transparent priority setting in health care based on specific ethical principles is requested by the Swedish Parliament since 1997. Implementation has been limited. In this case, transparent priority setting was performed for a second time round and engaged an entire health care organisation. Objectives were to refine a bottom-up priority setting process, reach a political decision on service limits to make reallocation towards higher prioritised services possible, and raise systems knowledge. An action research approach was chosen. The national model for priority setting was used with addition of dimensions costs, volumes, gender distribution and feasibility. The intervention included a three step process and specific procedures for each step which were created, revised and evaluated regarding factual and functional aspects. Evaluations methods included analyses of documents, recordings and surveys. Vertical and horizontal priority setting occurred and resources were reallocated. Participants' attitudes remained positive, however less so than in the first priority setting round. Identifying low-priority services was perceived difficult, causing resentment and strategic behaviour. The horizontal stage served to raise quality of the knowledge base, level out differences in ranking of services and raise systems knowledge. Existing health care management systems do not meet institutional requirements for transparent priority setting. Introducing transparent priority setting constitutes a complex institutional reform, which needs to be driven by management/administration. Strong managerial commitment is required. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Ugliness as the fourth wall-breaker. Comment on "Move me, astonish me... delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates" by Matthew Pelowski et al.

    Science.gov (United States)

    Ishizu, Tomohiro; Sakamoto, Yasuhiro

    2017-07-01

    In this extensive and valuable theoretical article, Pelowski et al. propose a psychological architecture in art appreciation by introducing the concepts of early/bottom-up and relatively late/top-down stages. The former is dictated as automatic processing on perceptual features of visual images, while the latter comprises cognitive and evaluative processes where modulations from acquired knowledge and memories come into play with recurrent loops to form final experiences, as well as brain areas/networks which possibly have a role in each processing component [9].

  7. Enhanced Photon Extraction from a Nanowire Quantum Dot Using a Bottom-Up Photonic Shell

    Science.gov (United States)

    Jeannin, Mathieu; Cremel, Thibault; Häyrynen, Teppo; Gregersen, Niels; Bellet-Amalric, Edith; Nogues, Gilles; Kheng, Kuntheak

    2017-11-01

    Semiconductor nanowires offer the possibility to grow high-quality quantum-dot heterostructures, and, in particular, CdSe quantum dots inserted in ZnSe nanowires have demonstrated the ability to emit single photons up to room temperature. In this paper, we demonstrate a bottom-up approach to fabricate a photonic fiberlike structure around such nanowire quantum dots by depositing an oxide shell using atomic-layer deposition. Simulations suggest that the intensity collected in our NA =0.6 microscope objective can be increased by a factor 7 with respect to the bare nanowire case. Combining microphotoluminescence, decay time measurements, and numerical simulations, we obtain a fourfold increase in the collected photoluminescence from the quantum dot. We show that this improvement is due to an increase of the quantum-dot emission rate and a redirection of the emitted light. Our ex situ fabrication technique allows a precise and reproducible fabrication on a large scale. Its improved extraction efficiency is compared to state-of-the-art top-down devices.

  8. Achieving integrated urban water management: planning top-down or bottom-up?

    Science.gov (United States)

    Gabe, J; Trowsdale, S; Vale, R

    2009-01-01

    Integrated Urban Water Management (IUWM) acknowledges a broad range of environmental and socio-economic outcomes but the link between design intentions and operational performance is not always clear. This may be due in part to a lack of shared principles that remove bias and inconsistency in assessing the operational performance of IUWM. This paper investigates the possibility of developing shared principles through examination of shared objectives and shared indicators within two logical and integrated frameworks for urban residential developments that aspire for IUWM and sustainable development. The framework method was applied using very different approaches-one a top-down urban planning process, the other a bottom-up community consultation process. Both frameworks highlight the extent to which IUWM is part of a broad social and environmental system. Core environmental performance objectives and indicators were very similar, highlighting the potential to develop shared principles in reporting and benchmarking the environmental performance of neighbourhood developments. Socio-economic indicators were highly variable due to process and likely contextual differences, thus it is unclear if the influence of IUWM on these variables can transcend the social context unless the practice of urban water management can expand its core responsibility beyond "hard" physical infrastructure.

  9. Bottom-up and top-down emotion generation: implications for emotion regulation.

    Science.gov (United States)

    McRae, Kateri; Misra, Supriya; Prasad, Aditya K; Pereira, Sean C; Gross, James J

    2012-03-01

    Emotion regulation plays a crucial role in adaptive functioning and mounting evidence suggests that some emotion regulation strategies are often more effective than others. However, little attention has been paid to the different ways emotions can be generated: from the 'bottom-up' (in response to inherently emotional perceptual properties of the stimulus) or 'top-down' (in response to cognitive evaluations). Based on a process priming principle, we hypothesized that mode of emotion generation would interact with subsequent emotion regulation. Specifically, we predicted that top-down emotions would be more successfully regulated by a top-down regulation strategy than bottom-up emotions. To test this hypothesis, we induced bottom-up and top-down emotions, and asked participants to decrease the negative impact of these emotions using cognitive reappraisal. We observed the predicted interaction between generation and regulation in two measures of emotional responding. As measured by self-reported affect, cognitive reappraisal was more successful on top-down generated emotions than bottom-up generated emotions. Neurally, reappraisal of bottom-up generated emotions resulted in a paradoxical increase of amygdala activity. This interaction between mode of emotion generation and subsequent regulation should be taken into account when comparing of the efficacy of different types of emotion regulation, as well as when reappraisal is used to treat different types of clinical disorders. © The Author (2011). Published by Oxford University Press.

  10. Learning affects top down and bottom up modulation of eye movements in decision making

    DEFF Research Database (Denmark)

    Orquin, Jacob Lund; Bagger, Martin; Mueller Loose, Simone

    2013-01-01

    it in a broader framework of top down and bottom up processes and derive the predictions that repeated decisions increase top down control of attention capture which in turn leads to a reduction in bottom up attention capture. To test our hypotheses we conducted a repeated discrete choice experiment with three...... about what defines a decision strategy. As an alternative view we suggest that temporal dynamics in decision making are driven by attentional and perceptual processes and that this view has been expressed in the information reduction hypothesis. We test the information reduction hypothesis by integrating...... different information presentation formats. We thereby operationalized top down and bottom up control as the effect of individual utility levels and presentation formats on attention capture on a trial-by-trial basis. The experiment revealed an increase in top down control of eye movements over time...

  11. A bottom-up partnership of Andean institutions to improve hydrological interventions using a participatory network of research basins

    Science.gov (United States)

    Buytaert, W.; Ochoa-Tocachi, B. F.; De Bièvre, B.

    2017-12-01

    Many watershed interventions in remote data-scarce areas respond to information gaps by extrapolating conventional approaches based on very limited local evidence. However, most interventions, including conservation strategies and adaptation measures, have not been evaluated properly for their hydrological benefits. This is particularly the case for the Andean region, where the complex climatic and hydrological characteristics combined with a very dynamic anthropogenic disturbance, require better monitoring. Here, we present the experience of a partnership of academic and non-governmental institutions who pioneered participatory hydrological monitoring in the Andes. Established in 2009, the Regional Initiative for Hydrological Monitoring of Andean Ecosystems (iMHEA), is a bottom-up initiative that complements the national monitoring networks and more conventional scientific observatories. Using a design based on a trading-space-for-time approach, over 30 paired catchments with a variety of watershed interventions are currently being monitored by 18 local stakeholders in 15 sites in the tropical Andes. Pooling these data into a hydrological impact model allowed the consortium to make more robust predictions about the effectiveness of catchment interventions to improve water resources management and to reduce risks. The collaborative nature of iMHEA has several strengths. We identify as most important of those the ability to: (i) standardize monitoring practices; (ii) ensure quality and technical support; (iii) share responsibility of monitoring activities; (iv) obtain project co-funding and complementarity; and, (v) promote decision maker-scientist engagement. As a result, this network has started to deliver useful information to multi-scale and multi-stakeholder decision making arenas. For example, in the context of growing investment in hydrological ecosystem services in Peru, the sites provide a new generation of hydrological information that allows for evidence

  12. Motivation and drives in bottom-up developments in natural hazards management: multiple-use of adaptation strategies in Austria

    Science.gov (United States)

    Thaler, Thomas; Fuchs, Sven

    2015-04-01

    Losses from extreme hydrological events, such as recently experienced in Europe have focused the attention of policymakers as well as researchers on vulnerability to natural hazards. In parallel, the context of changing flood risks under climate and societal change is driving transformation in the role of the state in responsibility sharing and individual responsibilities for risk management and precaution. The new policy agenda enhances the responsibilities of local authorities and private citizens in hazard management and reduces the role of central governments. Within the objective is to place added responsibility on local organisations and citizens to determine locally-based strategies for risk reduction. A major challenge of modelling adaptation is to represent the complexity of coupled human-environmental systems and particularly the feedback loops between environmental dynamics and human decision-making processes on different scales. This paper focuses on bottom-up initiatives to flood risk management which are, by definition, different from the mainstream. These initiatives are clearly influenced (positively or negatively) by a number of factors, where the combination of these interdependences can create specific conditions that alter the opportunity for effective governance arrangements in a local scheme approach. In total, this study identified six general drivers which encourage the implementation of flood storages, such as direct relation to recent major flood frequency and history, the initiative of individual stakeholders (promoters), political pressures from outside (e.g. business companies, private households) and a strong solidarity attitude of municipalities and the stakeholders involved. Although partnership approach may be seen as an 'optimal' solution for flood risk management, in practice there are many limitations and barriers in establishing these collaborations and making them effective (especially in the long term) with the consequences

  13. Top-down and bottom-up neurodynamic evidence in patients with tinnitus.

    Science.gov (United States)

    Hong, Sung Kwang; Park, Sejik; Ahn, Min-Hee; Min, Byoung-Kyong

    2016-12-01

    Although a peripheral auditory (bottom-up) deficit is an essential prerequisite for the generation of tinnitus, central cognitive (top-down) impairment has also been shown to be an inherent neuropathological mechanism. Using an auditory oddball paradigm (for top-down analyses) and a passive listening paradigm (for bottom-up analyses) while recording electroencephalograms (EEGs), we investigated whether top-down or bottom-up components were more critical in the neuropathology of tinnitus, independent of peripheral hearing loss. We observed significantly reduced P300 amplitudes (reflecting fundamental cognitive processes such as attention) and evoked theta power (reflecting top-down regulation in memory systems) for target stimuli at the tinnitus frequency of patients with tinnitus but without hearing loss. The contingent negative variation (reflecting top-down expectation of a subsequent event prior to stimulation) and N100 (reflecting auditory bottom-up selective attention) were different between the healthy and patient groups. Interestingly, when tinnitus patients were divided into two subgroups based on their P300 amplitudes, their P170 and N200 components, and annoyance and distress indices to their tinnitus sound were different. EEG theta-band power and its Granger causal neurodynamic results consistently support a double dissociation of these two groups in both top-down and bottom-up tasks. Directed cortical connectivity corroborates that the tinnitus network involves the anterior cingulate and the parahippocampal areas, where higher-order top-down control is generated. Together, our observations provide neurophysiological and neurodynamic evidence revealing a differential engagement of top-down impairment along with deficits in bottom-up processing in patients with tinnitus but without hearing loss. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  14. "Bottom-Up" Construction of Hyperbranched Poly(prodrug-co-photosensitizer) Amphiphiles Unimolecular Micelles for Chemo-Photodynamic Dual Therapy.

    Science.gov (United States)

    Sun, Pei; Wang, Nan; Jin, Xin; Zhu, Xinyuan

    2017-10-25

    Despite the great advantages of chemo-photodynamic combination therapy, tedious synthesis steps and laborious purification procedures make the fabrication of chemo-photodynamic combined therapeutic platforms rather difficult. In this study, we develop a facile "bottom-up" strategy to fabricate hyperbranched poly(prodrug-co-photosensitizer) amphiphiles, h-P(CPTMA-co-BYMAI)-b-POEGMA (hPCBE), for chemo-photodynamic dual therapy. The easily prepared hPCBE possess a bottom-up-constructed hydrophobic core h-P(CPTMA-co-BYMAI) (hPCB) direct copolymerized from reduction-responsive CPT prodrug monomer (CPTMA) and boron dipyrromethene-based photosensitizer monomer (BYMAI), as well as a biocompatible shell polymerized from hydrophilic monomers. Because of the covalently interconnected core-shell structure, hPCBE exists as unimolecular micelles in aqueous solution and exhibits excellent structural stability under dilution condition. The hPCBE micelles can be effectively internalized by MCF-7 cells and release CPT triggered by the reductive milieu. In addition, photosensitizer moieties embedded in the hPCB core could generate singlet oxygen ( 1 O 2 ) effectively under irradiation, endowing hPCBE with the boosting of chemotherapeutic efficacy. As compared to the single chemotherapy of hyperbranched polyprodrug amphiphiles h-PCPTMA-b-POEGMA (hPCE) and photodynamic therapy of hyperbranched polyphotosensitizer amphiphiles h-PBYMAI-b-POEGMA (hPBE), hPCBE shows higher in vitro cytotoxicity. We expect that our approach will further boost research on the design of multifunctional drug delivery systems via the facile "bottom-up" strategy.

  15. Temperature regulation of marine heterotrophic prokaryotes increases latitudinally as a breach between bottom-up and top-down controls

    KAUST Repository

    Moran, Xose Anxelu G.

    2017-04-19

    Planktonic heterotrophic prokaryotes make up the largest living biomass and process most organic matter in the ocean. Determining when and where the biomass and activity of heterotrophic prokaryotes are controlled by resource availability (bottom-up), predation and viral lysis (top-down) or temperature will help in future carbon cycling predictions. We conducted an extensive survey across subtropical and tropical waters of the Atlantic, Indian and Pacific Oceans during the Malaspina 2010 Global Circumnavigation Expedition and assessed indices for these three types of controls at 109 stations (mostly from the surface to 4000 m depth). Temperature control was approached by the apparent activation energy in eV (ranging from 0.46 to 3.41), bottom-up control by the slope of the log-log relationship between biomass and production rate (ranging from -0.12 to 1.09) and top-down control by an index that considers the relative abundances of heterotrophic nanoflagellates and viruses (ranging from 0.82 to 4.83). We conclude that temperature becomes dominant (i.e. activation energy >1.5 eV) within a narrow window of intermediate values of bottom-up (0.3-0.6) and top-down 0.8-1.2) controls. A pervasive latitudinal pattern of decreasing temperature regulation towards the Equator, regardless of the oceanic basin, suggests that the impact of global warming on marine microbes and their biogeochemical function will be more intense at higher latitudes. Our analysis predicts that 1°C ocean warming will result in increased biomass of heterotrophic prokaryoplankton only in waters with <26°C of mean annual surface temperature. This article is protected by copyright. All rights reserved.

  16. Top-down or bottom-up: Contrasting perspectives on psychiatric diagnoses

    Directory of Open Access Journals (Sweden)

    Willem MA Verhoeven

    2008-09-01

    Full Text Available Willem MA Verhoeven1,2, Siegfried Tuinier1, Ineke van der Burgt31Vincent van Gogh Institute for Psychiatry, Venray, The Netherlands; 2Department of Psychiatry, Erasmus University Medical Centre, Rotterdam, The Netherlands; 3Department of Human Genetics, Radboud University Medical Centre, Nijmegen, The NetherlandsAbstract: Clinical psychiatry is confronted with the expanding knowledge of medical genetics. Most of the research into the genetic underpinnings of major mental disorders as described in the categorical taxonomies, however, did reveal linkage with a variety of chromosomes. This heterogeneity of results is most probably due to the assumption that the nosological categories as used in these studies are disease entities with clear boundaries. If the reverse way of looking, the so-called bottom-up approach, is applied, it becomes clear that genetic abnormalities are in most cases not associated with a single psychiatric disorder but with a certain probability to develop a variety of aspecific psychiatric symptoms. The adequacy of the categorical taxonomy, the so-called top-down approach, seems to be inversely related to the amount of empirical etiological data. This is illustrated by four rather prevalent genetic syndromes, fragile X syndrome, Prader-Willi syndrome, 22q11 deletion syndrome, and Noonan syndrome, as well as by some cases with rare chromosomal abnormalities. From these examples, it becomes clear that psychotic symptoms as well as mood, anxiety, and autistic features can be found in a great variety of different genetic syndromes. A psychiatric phenotype exists, but comprises, apart from the chance to present several psychiatric symptoms, all elements from developmental, neurocognitive, and physical characteristics.Keywords: genetic disorders, psychiatric symptoms, phenotype, mental disorders

  17. Public engagement as a field of tension between bottom-up and top-down strategies

    DEFF Research Database (Denmark)

    Horsbøl, Anders; Lassen, Inger

    2012-01-01

    . These initiatives often have to deal with dilemmas between participatory aspects and other considerations such as planning efficiency, dilemmas that potentially bring about tension between bottom-up and top-down strategies. Literature on climate change issues has addressed the failure of public response, which has...

  18. The Girlfriends Project: Evaluating a Promising Community-Based Intervention from a Bottom-Up Perspective

    Science.gov (United States)

    Hawk, Mary

    2015-01-01

    Randomized controlled trials are the gold standard in research but may not fully explain or predict outcome variations in community-based interventions. Demonstrating efficacy of externally driven programs in well-controlled environments may not translate to community-based implementation where resources and priorities vary. A bottom-up evaluation…

  19. Achieving Campus Sustainability: Top-Down, Bottom-Up, or Neither?

    Science.gov (United States)

    Brinkhurst, Marena; Rose, Peter; Maurice, Gillian; Ackerman, Josef Daniel

    2011-01-01

    Purpose: The dynamics of organizational change related to environmental sustainability on university campuses are examined in this article. Whereas case studies of campus sustainability efforts tend to classify leadership as either "top-down" or "bottom-up", this classification neglects consideration of the leadership roles of…

  20. Oriented bottom-up growth of armchair graphene nanoribbons on germanium

    Science.gov (United States)

    Arnold, Michael Scott; Jacobberger, Robert Michael

    2016-03-15

    Graphene nanoribbon arrays, methods of growing graphene nanoribbon arrays and electronic and photonic devices incorporating the graphene nanoribbon arrays are provided. The graphene nanoribbons in the arrays are formed using a scalable, bottom-up, chemical vapor deposition (CVD) technique in which the (001) facet of the germanium is used to orient the graphene nanoribbon crystals along the [110] directions of the germanium.

  1. Book Review: Police reform from the bottom up | van der Spuy ...

    African Journals Online (AJOL)

    Title: Police reform from the bottom up: officers and their unions as agents of change. Editors: Monique Marks and David Sklansky Publisher: Routledge Price: $125. Pages: 176. Availability: Published ISBN: 13:978-0-415-68679-2. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT ...

  2. Bottom-up processes influence the demography and life-cycle phenology of Hawaiian bird communities

    Science.gov (United States)

    Jared D. Wolfe; C. John Ralph; Andrew Wiegardt

    2017-01-01

    Changes in climate can indirectly regulate populations at higher trophic levels by influencing the availability of food resources in the lower reaches of the food web. As such, species that rely on fruit and nectar food resources may be particularly sensitive to these bottom-up perturbations due to the strength of their trophic linkages with climatically-...

  3. Bottom-up and top-down tree transformations - a comparison

    NARCIS (Netherlands)

    Engelfriet, Joost

    1975-01-01

    The top-down and bottom-up tree transducer are incomparable with respect to their transformation power. The difference between them is mainly caused by the different order in which they use the facilities of copying and nondeterminism. One can however define certain simple tree transformations,

  4. Contributions of Bottom-Up Energy Transitions in Germany: A Case Study Analysis

    Directory of Open Access Journals (Sweden)

    Ortzi Akizu

    2018-04-01

    Full Text Available Within the context of an energy transition towards achieving a renewable low-impact energy consumption system, this study analyses how bottom-up initiatives can contribute to state driven top-down efforts to achieve the sustainability related goals of (1 reducing total primary energy consumption; (2 reducing residential electricity and heat consumption; and (3 increasing generated renewable energy and even attaining self-sufficiency. After identifying the three most cited German bottom-up energy transition cases, the initiatives have been qualitatively and quantitatively analysed. The case study methodology has been used and each initiative has been examined in order to assess and compare these with the German national panorama. The novel results of the analysis demonstrate the remarkable effects of communal living, cooperative investment and participatory processes on the creation of a new sustainable energy system. The study supports the claim that bottom-up initiatives could also contribute to energy sustainability goals together within the state driven plans. Furthermore, the research proves that the analysed bottom-up transitions are not only environmentally and socially beneficial but they can also be economically feasible, at least in a small scale, such as the current German national top-down energy policy panorama.

  5. Bottom-up Electrosynthesis of Highly Active Tungsten Sulfide (WS3-x) Films for Hydrogen Evolution.

    Science.gov (United States)

    Tan, Shu Min; Pumera, Martin

    2016-02-17

    Transition metal dichalcogenides have been extensively studied as promising earth-abundant electrocatalysts for hydrogen evolution reaction (HER). However, despite the intention to achieve sustainable energy generation, conventional syntheses typically use environmentally damaging reagents and energy-demanding preparation conditions. Hence, we present electrochemical synthesis as a green and versatile alternative to traditional methods. In this fundamental study, we demonstrated the bottom-up synthesis of a mixed WS2/WS3 film-like material via cyclic voltammetry (CV). The film-like material can be directly electrosynthesized on any conductive substrates and renders the catalyst immobilization step redundant. Through stepwise analysis of deposition voltammograms facilitated by straightforward modification of CV conditions, and characterization using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), a two-step mechanism involving the initial WS3 deposition and subsequent partial reduction to WS2 was proposed. The WS2/WS3 material was determined to possess composition of WS2.64. Compared to non-electrosynthesized WSx materials, its predominantly basal orientation limited the heterogeneous electron transfer rate toward surface-sensitive redox couples. However, WS2.64 demonstrated excellent HER activity, with the lowest Tafel slope of 43.7 mV dec(-1) to date; this was attributed to different metal-chalcogen binding strengths within WS2.64. Fundamental understanding of the electrosynthesis process is crucial for green syntheses of inexpensive and highly electrocatalytically active materials for sustainable energy production. Albeit, the process may be different for a myriad of nanomaterials, this study can be exploited for its analyses from which the conclusions were made, to empower electrochemical synthesis as the prime fabrication approach for HER electrocatalyst development.

  6. Bottom-up engineering of thermoelectric nanomaterials and devices from solution-processed nanoparticle building blocks.

    Science.gov (United States)

    Ortega, Silvia; Ibáñez, Maria; Liu, Yu; Zhang, Yu; Kovalenko, Maksym V; Cadavid, Doris; Cabot, Andreu

    2017-06-19

    The conversion of thermal energy to electricity and vice versa by means of solid state thermoelectric devices is extremely appealing. However, its cost-effectiveness is seriously hampered by the relatively high production cost and low efficiency of current thermoelectric materials and devices. To overcome present challenges and enable a successful deployment of thermoelectric systems in their wide application range, materials with significantly improved performance need to be developed. Nanostructuration can help in several ways to reach the very particular group of properties required to achieve high thermoelectric performances. Nanodomains inserted within a crystalline matrix can provide large charge carrier concentrations without strongly influencing their mobility, thus allowing to reach very high electrical conductivities. Nanostructured materials contain numerous grain boundaries that efficiently scatter mid- and long-wavelength phonons thus reducing the thermal conductivity. Furthermore, nanocrystalline domains can enhance the Seebeck coefficient by modifying the density of states and/or providing type- and energy-dependent charge carrier scattering. All these advantages can only be reached when engineering a complex type of material, nanocomposites, with exquisite control over structural and chemical parameters at multiple length scales. Since current conventional nanomaterial production technologies lack such level of control, alternative strategies need to be developed and adjusted to the specifics of the field. A particularly suitable approach to produce nanocomposites with unique level of control over their structural and compositional parameters is their bottom-up engineering from solution-processed nanoparticles. In this work, we review the state-of-the-art of this technology applied to the thermoelectric field, including the synthesis of nanoparticles of suitable materials with precisely engineered composition and surface chemistry, their combination

  7. Savanna tree density, herbivores, and the herbaceous community: bottom-up vs. top-down effects.

    Science.gov (United States)

    Riginos, Corinna; Grace, James B

    2008-08-01

    Herbivores choose their habitats both to maximize forage intake and to minimize their risk of predation. For African savanna herbivores, the available habitats range in woody cover from open areas with few trees to dense, almost-closed woodlands. This variation in woody cover or density can have a number of consequences for herbaceous species composition, cover, and productivity, as well as for ease of predator detection and avoidance. Here, we consider two alternative possibilities: first, that tree density affects the herbaceous vegetation, with concomitant "bottom-up" effects on herbivore habitat preferences; or, second, that tree density affects predator visibility, mediating "top-down" effects of predators on herbivore habitat preferences. We sampled sites spanning a 10-fold range of tree densities in an Acacia drepanolobium-dominated savanna in Laikipia, Kenya, for variation in (1) herbaceous cover, composition, and species richness; (2) wild and domestic herbivore use; and (3) degree of visibility obstruction by the tree layer. We then used structural equation modeling to consider the potential influences that tree density may have on herbivores and herbaceous community properties. Tree density was associated with substantial variation in herbaceous species composition and richness. Cattle exhibited a fairly uniform use of the landscape, whereas wild herbivores, with the exception of elephants, exhibited a strong preference for areas of low tree density. Model results suggest that this was not a response to variation in herbaceous-community characteristics, but rather a response to the greater visibility associated with more open places. Elephants, in contrast, preferred areas with higher densities of trees, apparently because of greater forage availability. These results suggest that, for all but the largest species, top-down behavioral effects of predator avoidance on herbivores are mediated by tree density. This, in turn, appears to have cascading effects

  8. Assessment of discrepancies between bottom-up and regional emission inventories in Norwegian urban areas

    Science.gov (United States)

    López-Aparicio, Susana; Guevara, Marc; Thunis, Philippe; Cuvelier, Kees; Tarrasón, Leonor

    2017-04-01

    This study shows the capabilities of a benchmarking system to identify inconsistencies in emission inventories, and to evaluate the reason behind discrepancies as a mean to improve both bottom-up and downscaled emission inventories. Fine scale bottom-up emission inventories for seven urban areas in Norway are compared with three regional emission inventories, EC4MACS, TNO_MACC-II and TNO_MACC-III, downscaled to the same areas. The comparison shows discrepancies in nitrogen oxides (NOx) and particulate matter (PM2.5 and PM10) when evaluating both total and sectorial emissions. The three regional emission inventories underestimate NOx and PM10 traffic emissions by approximately 20-80% and 50-90%, respectively. The main reasons for the underestimation of PM10 emissions from traffic in the regional inventories are related to non-exhaust emissions due to resuspension, which are included in the bottom-up emission inventories but are missing in the official national emissions, and therefore in the downscaled regional inventories. The benchmarking indicates that the most probable reason behind the underestimation of NOx traffic emissions by the regional inventories is the activity data. The fine scale NOx traffic emissions from bottom-up inventories are based on the actual traffic volume at the road link and are much higher than the NOx emissions downscaled from national estimates based on fuel sales and based on population for the urban areas. We have identified important discrepancies in PM2.5 emissions from wood burning for residential heating among all the inventories. These discrepancies are associated with the assumptions made for the allocation of emissions. In the EC4MACs inventory, such assumptions imply high underestimation of PM2.5 emissions from the residential combustion sector in urban areas, which ranges from 40 to 90% compared with the bottom-up inventories. The study shows that in three of the seven Norwegian cities there is need for further improvement of

  9. Economic burden associated with alcohol dependence in a German primary care sample: a bottom-up study

    Directory of Open Access Journals (Sweden)

    Jakob Manthey

    2016-08-01

    Full Text Available Abstract Background A considerable economic burden has been repeatedly associated with alcohol dependence (AD – mostly calculated using aggregate data and alcohol-attributable fractions (top-down approach. However, this approach is limited by a number of assumptions, which are hard to test. Thus, cost estimates should ideally be validated with studies using individual data to estimate the same costs (bottom-up approach. However, bottom-up studies on the economic burden associated with AD are lacking. Our study aimed to fill this gap using the bottom-up approach to examine costs for AD, and also stratified the results by the following subgroups: sex, age, diagnostic approach and severity of AD, as relevant variations could be expected by these factors. Methods Sample: 1356 primary health care patients, representative for two German regions. AD was diagnosed by a standardized instrument and treating physicians. Individual costs were calculated by combining resource use and productivity data representing a period of six months prior to the time of interview, with unit costs derived from the literature or official statistics. The economic burden associated with AD was determined via excess costs by comparing utilization of various health care resources and impaired productivity between people with and without AD, controlling for relevant confounders. Additional analyses for several AD characteristics were performed. Results Mean costs among alcohol dependent patients were 50 % higher compared to the remaining patients, resulting in 1836 € excess costs per alcohol dependent patient in 6 months. More than half of these excess costs incurred through increased productivity loss among alcohol dependent patients. Treatment for alcohol problems represents only 6 % of these costs. The economic burden associated with AD incurred mainly among males and among 30 to 49 year old patients. Both diagnostic approaches were significantly related to the

  10. Sample Clean-up Strategies for ESI Mass Spectrometry Applications in Bottom-up Proteomics: Trends from 2012 to 2016.

    Science.gov (United States)

    Tubaon, Ria Marni; Haddad, Paul R; Quirino, Joselito P

    2017-10-01

    Bottom-up proteomics is a mass spectrometric (MS)-based approach for the characterization of peptides obtained from in-solution protein digestion. MS is favored over other methods for peptide and protein analysis because of its better sensitivity and high throughput. Inorganic ions and surfactants present in the sample or produced during tryptic digestion are detrimental in MS analysis and affect the proteome data, thus sample preparation for removal of these unwanted components has become essential. Here, we review 48 research papers on strategies for removal of salts and surfactants (in particular, SDS) prior to ESI-MS analysis in bottom-up proteomics from 2012 to 2016. The strategies were mostly based on SPE and membrane-based filter-aided sample preparation for salt and SDS removal, respectively. Some known limitations of SPE and filter-aided sample preparation procedures are that they can be time consuming, laborious, and require the use of organic solvents before a concentrated extract suitable for analysis is obtained. The development of faster analytical methods by reducing the sample preparation time and thereby, increasing sample throughput, and in a solvent-less and membrane-less operation, is a significant contribution to proteome research. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Nitrogen and water inputs to tomato plant do not trigger bottom-up effects on a leafminer parasitoid through host and non-host exposures.

    Science.gov (United States)

    Dong, Yong-Cheng; Han, Peng; Niu, Chang-Ying; Zappalà, Lucia; Amiens-Desneux, Edwige; Bearez, Philippe; Lavoir, Anne-Violette; Biondi, Antonio; Desneux, Nicolas

    2018-03-01

    Bottom-up and top-down forces are major components of biological control against pests in an agro-ecosystem. Understanding the multi-trophic interactions between plants and secondary consumers would help optimize pest control strategies. We manipulated nitrogen and/or water inputs to tomato plants (Solanum lycopersicum) to test whether these manipulations could trigger bottom-up effects on the parasitoid Necremnus tutae via host (Tuta absoluta) and/or non-host (Bemisia tabaci) exposures, and compared the control efficacy of N. tutae on T. absoluta in the presence and absence of B. tabaci. The results showed no cascading effects of plant nitrogen and/or water inputs on N. tutae via either host or non-host exposure. The bottom-up force was mitigated by chewing or sap-feeding insect consumers at the second energy level. By contrast, the top-down force on T. absoluta from parasitoids was enhanced by an additionally provided non-host, which could produce alternative food sources extending N. tutae longevity and enhancing the fitness of its offspring. Our results provided evidence for the combination of bottom-up and top-down approaches in tomato integrated pest management programs. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  12. Evidence of bottom-up limitations in nearshore marine systems based on otolith proxies of fish growth

    Science.gov (United States)

    von Biela, Vanessa R.; Kruse, Gordon H.; Mueter, Franz J.; Black, Bryan A.; Douglas, David C.; Helser, Thomas E.; Zimmerman, Christian E.

    2015-01-01

    Fish otolith growth increments were used as indices of annual production at nine nearshore sites within the Alaska Coastal Current (downwelling region) and California Current (upwelling region) systems (~36–60°N). Black rockfish (Sebastes melanops) and kelp greenling (Hexagrammos decagrammus) were identified as useful indicators in pelagic and benthic nearshore food webs, respectively. To examine the support for bottom-up limitations, common oceanographic indices of production [sea surface temperature (SST), upwelling, and chlorophyll-a concentration] during summer (April–September) were compared to spatial and temporal differences in fish growth using linear mixed models. The relationship between pelagic black rockfish growth and SST was positive in the cooler Alaska Coastal Current and negative in the warmer California Current. These contrasting growth responses to SST among current systems are consistent with the optimal stability window hypothesis in which pelagic production is maximized at intermediate levels of water column stability. Increased growth rates of black rockfish were associated with higher chlorophyll concentrations in the California Current only, but black rockfish growth was unrelated to the upwelling index in either current system. Benthic kelp greenling growth rates were positively associated with warmer temperatures and relaxation of downwelling (upwelling index near zero) in the Alaska Coastal Current, while none of the oceanographic indices were related to their growth in the California Current. Overall, our results are consistent with bottom-up forcing of nearshore marine ecosystems—light and nutrients constrain primary production in pelagic food webs, and temperature constrains benthic food webs.

  13. Mechanisms of knowledge flows in bottom-up and top-down cluster initiatives

    Directory of Open Access Journals (Sweden)

    Wojciech Dyba

    2016-01-01

    Full Text Available Knowledge flows are widely believed to be a phenomenon of clusters, and inducing them is one of the chief objectives in establishing and promoting cluster initiatives (CI. However, not many studies discuss how these flows and their effects may differ depending on the mode of CI creation and on the role of public authorities in this process. The main aim of this article is to compare mechanisms of knowledge flows in bottom-up and top-down cluster initiatives. The results of an empirical research involving two case studies in western Poland, obtained through the use of Social Network Analysis (SNA, allowed stating that in bottom-up cluster initiatives firms which were innovation leaders played a prime role in disseminating technological and business knowledge, while in the top-down initiatives the most important were representatives of universities and research centres as well as formal coordinators of cooperation. Policy implications stemming from these results were identified.

  14. Top-down versus bottom-up processing of influence diagrams in probabilistic analysis

    International Nuclear Information System (INIS)

    Timmerman, R.D.; Burns, T.J.; Dodds, H.L. Jr.

    1984-01-01

    Recent work by Phillips et al., and Selby et al., has shown that influence diagram methodology can be a useful analytical tool in reactor safety studies. An influence diagram is a graphical representation of probabilistic dependence within a system or event sequence. Bayesian statistics are employed to transform the relationships depicted in the influence diagram into the correct expression for a desired marginal probability (e.g. the top event). As with fault trees, top-down and bottom-up algorithms have emerged as the dominant methods for quantifying influence diagrams. Purpose of this paper is to demonstrate a potential error in employing the bottom-up algorithm when dealing with interdependencies. In addition, the computing efficiency of both methods is discussed

  15. A two-step combination of top-down and bottom-up fire emission estimates at regional and global scales: strengths and main uncertainties

    Science.gov (United States)

    Sofiev, Mikhail; Soares, Joana; Kouznetsov, Rostislav; Vira, Julius; Prank, Marje

    2016-04-01

    Top-down emission estimation via inverse dispersion modelling is used for various problems, where bottom-up approaches are difficult or highly uncertain. One of such areas is the estimation of emission from wild-land fires. In combination with dispersion modelling, satellite and/or in-situ observations can, in principle, be used to efficiently constrain the emission values. This is the main strength of the approach: the a-priori values of the emission factors (based on laboratory studies) are refined for real-life situations using the inverse-modelling technique. However, the approach also has major uncertainties, which are illustrated here with a few examples of the Integrated System for wild-land Fires (IS4FIRES). IS4FIRES generates the smoke emission and injection profile from MODIS and SEVIRI active-fire radiative energy observations. The emission calculation includes two steps: (i) initial top-down calibration of emission factors via inverse dispersion problem solution that is made once using training dataset from the past, (ii) application of the obtained emission coefficients to individual-fire radiative energy observations, thus leading to bottom-up emission compilation. For such a procedure, the major classes of uncertainties include: (i) imperfect information on fires, (ii) simplifications in the fire description, (iii) inaccuracies in the smoke observations and modelling, (iv) inaccuracies of the inverse problem solution. Using examples of the fire seasons 2010 in Russia, 2012 in Eurasia, 2007 in Australia, etc, it is pointed out that the top-down system calibration performed for a limited number of comparatively moderate cases (often the best-observed ones) may lead to errors in application to extreme events. For instance, the total emission of 2010 Russian fires is likely to be over-estimated by up to 50% if the calibration is based on the season 2006 and fire description is simplified. Longer calibration period and more sophisticated parameterization

  16. Selective spatial attention modulates bottom-up informational masking of speech

    OpenAIRE

    Carlile, Simon; Corkhill, Caitlin

    2015-01-01

    To hear out a conversation against other talkers listeners overcome energetic and informational masking. Largely attributed to top-down processes, information masking has also been demonstrated using unintelligible speech and amplitude-modulated maskers suggesting bottom-up processes. We examined the role of speech-like amplitude modulations in information masking using a spatial masking release paradigm. Separating a target talker from two masker talkers produced a 20?dB improvement in speec...

  17. Brain networks of bottom-up triggered and top-down controlled shifting of auditory attention.

    Science.gov (United States)

    Salmi, Juha; Rinne, Teemu; Koistinen, Sonja; Salonen, Oili; Alho, Kimmo

    2009-08-25

    During functional magnetic resonance imaging (fMRI), our participants selectively attended to tone streams at the left or right, and occasionally shifted their attention from one stream to another as guided by a centrally presented visual cue. Duration changes in the to-be-attended stream served as targets. Loudness deviating tones (LDTs) occurred infrequently in both streams to catch attention in a bottom-up manner, as indicated by their effects on reaction times to targets. LDTs activated the right temporo-parietal junction (TPJ), posterior parts of the left inferior/middle frontal gyrus (IFG/MFG), ventromedial parts of the superior parietal lobule (SPL), and left frontal eye field/premotor cortex (FEF/PMC). In addition, LDTs in the to-be-ignored sound stream were associated with enhanced activity in the ventromedial prefrontal cortex (VMPFC) possibly related to evaluation of the distracting event. Top-down controlled cue-guided attention shifts (CASs) activated bilateral areas in the SPL, intraparietal sulcus (IPS), FEF/PMC, TPJ, IFG/MFG, and cingulate/medial frontal gyrus, and crus I/II of the cerebellum. Thus, our results suggest that in audition top-down controlled and bottom-up triggered shifting of attention activate largely overlapping temporo-parietal, superior parietal and frontal areas. As the IPS, superior parts of the SPL, and crus I/II were activated specifically by top-down controlled attention shifts, and the VMPFC was specifically activated by bottom-up triggered attention shifts, our results also suggest some differences between auditory top-down controlled and bottom-up triggered shifting of attention.

  18. The impact of QCD plasma instabilities on bottom-up thermalization

    OpenAIRE

    Bodeker, Dietrich

    2005-01-01

    QCD plasma instabilities, caused by an anisotropic momentum distributions of the particles in the plasma, are likely to play an important role in thermalization in heavy ion collisions. We consider plasmas with two different components of particles, one strongly anisotropic and one isotropic or nearly isotropic. The isotropic component does not eliminate instabilities but it decreases their growth rates. We investigate the impact of plasma instabilities on the first stage of the ``bottom-up''...

  19. A Bottom-up Trend in Research of Management of Technology

    Directory of Open Access Journals (Sweden)

    Yoko Ishino

    2014-12-01

    Full Text Available Management of Technology (MOT is defined as an academic discipline of management that enables organizations to manage their technological fundamentals to create competitive advantage. MOT covers a wide range of contents including administrative strategy, R&D management, manufacturing management, technology transfer, production control, marketing, accounting, finance, business ethics, and others. For each topic, researchers have conducted their MOT research at various levels. However, a practical and pragmatic side of MOT surely affects its research trends. Finding changes of MOT research trends, or the chronological transitions of principal subjects, can help understand the key concepts of current MOT. This paper studied a bottom-up trend in research fields in MOT by applying a text-mining method to the conference proceedings of IAMOT (International Association for Management of Technology. First, focusing on only nouns found several keywords, which more frequently emerge over time in the IAMOT proceedings. Then, expanding the scope into other parts of speech viewed the keywords in a natural context. Finally, it was found that the use of an important keyword has qualitatively and quantitatively extended over time. In conclusion, a bottom-up trend in MOT research was detected and the effects of the social situation on the trend were discussed.Keywords: Management of Technology; Text Mining; Research Trend; Bottom-up Trend; Patent

  20. Bottom-up effects of geologic parent material through ecological interaction webs

    Science.gov (United States)

    Bradley, R.

    2012-04-01

    Community ecologists study the interactions between species to understand what controls the distribution and abundance of different populations. Communities are thus portrayed as "interaction webs", in which different species exert reciprocal pressures on each other. In the case of one population being a resource for which another population is the consumer (i.e. food-web), reciprocal pressures are commonly referred to as "bottom-up" vs. "top-down" effects. The starting point for studying bottom-up effects is usually the vegetation (primary producers), and its end-point the decomposer community responsible for breaking down detrital matter from each trophic level. In my presentation, I will present results from three former graduate students, to argue that the starting point for studying bottom-up effects should be the geologic parent material (GPM), whose importance has often been overlooked by community ecologists. For example, our data show that GPM had a stronger effect on forest floor nutrient budgets than the identity or successional stage of the vegetation. Likewise, GPM had a strong effect on the structure of forest floor microbial communities, as well as their resistance to, and resilience from, disturbance. GPM also had a significant effect on the richness and diversity of understory plant communities from similar forest stands. Finally, we present evidence that soil fertility controls the resistance and tolerance of certain plant species to selective browsing, thereby affecting the composition of the dominant plant cover and the feeding patterns of large herbivores.

  1. Sensitivity of California water supply to changes in runoff magnitude and timing: A bottom-up assessment of vulnerabilities and adaptation strategies

    Science.gov (United States)

    Fefer, M.; Dogan, M. S.; Herman, J. D.

    2017-12-01

    Long-term shifts in the timing and magnitude of reservoir inflows will potentially have significant impacts on water supply reliability in California, though projections remain uncertain. Here we assess the vulnerability of the statewide system to changes in total annual runoff (a function of precipitation) and the fraction of runoff occurring during the winter months (primarily a function of temperature). An ensemble of scenarios is sampled using a bottom-up approach and compared to the most recent available streamflow projections from the state's 4th Climate Assessment. We evaluate these scenarios using a new open-source version of the CALVIN model, a network flow optimization model encompassing roughly 90% of the urban and agricultural water demands in California, which is capable of running scenario ensembles on a high-performance computing cluster. The economic representation of water demand in the model yields several advantages for this type of analysis: optimized reservoir operating policies to minimize shortage cost and the marginal value of adaptation opportunities, defined by shadow prices on infrastructure and regulatory constraints. Results indicate a shift in optimal reservoir operations and high marginal value of additional reservoir storage in the winter months. The collaborative management of reservoirs in CALVIN yields increased storage in downstream reservoirs to store the increased winter runoff. This study contributes an ensemble evaluation of a large-scale network model to investigate uncertain climate projections, and an approach to interpret the results of economic optimization through the lens of long-term adaptation strategies.

  2. Cost development of future technologies for power generation-A study based on experience curves and complementary bottom-up assessments

    International Nuclear Information System (INIS)

    Neij, Lena

    2008-01-01

    Technology foresight studies have become an important tool in identifying realistic ways of reducing the impact of modern energy systems on the climate and the environment. Studies on the future cost development of advanced energy technologies are of special interest. One approach widely adopted for the analysis of future cost is the experience curve approach. The question is, however, how robust this approach is, and which experience curves should be used in energy foresight analysis. This paper presents an analytical framework for the analysis of future cost development of new energy technologies for electricity generation; the analytical framework is based on an assessment of available experience curves, complemented with bottom-up analysis of sources of cost reductions and, for some technologies, judgmental expert assessments of long-term development paths. The results of these three methods agree in most cases, i.e. the cost (price) reductions described by the experience curves match the incremental cost reduction described in the bottom-up analysis and the judgmental expert assessments. For some technologies, the bottom-up analysis confirms large uncertainties in future cost development not captured by the experience curves. Experience curves with a learning rate ranging from 0% to 20% are suggested for the analysis of future cost development

  3. A framework for assessing inter-individual variability in pharmacokinetics using virtual human populations and integrating general knowledge of physical chemistry, biology, anatomy, physiology and genetics: A tale of 'bottom-up' vs 'top-down' recognition of covariates.

    Science.gov (United States)

    Jamei, Masoud; Dickinson, Gemma L; Rostami-Hodjegan, Amin

    2009-01-01

    An increasing number of failures in clinical stages of drug development have been related to the effects of candidate drugs in a sub-group of patients rather than the 'average' person. Expectation of extreme effects or lack of therapeutic effects in some subgroups following administration of similar doses requires a full understanding of the issue of variability and the importance of identifying covariates that determine the exposure to the drug candidates in each individual. In any drug development program the earlier these covariates are known the better. An important component of the drive to decrease this failure rate in drug development involves attempts to use physiologically-based pharmacokinetics 'bottom-up' modeling and simulation to optimize molecular features with respect to the absorption, distribution, metabolism and elimination (ADME) processes. The key element of this approach is the separation of information on the system (i.e. human body) from that of the drug (e.g. physicochemical characteristics determining permeability through membranes, partitioning to tissues, binding to plasma proteins or affinities toward certain enzymes and transporter proteins) and the study design (e.g. dose, route and frequency of administration, concomitant drugs and food). In this review, the classical 'top-down' approach in covariate recognition is compared with the 'bottom-up' paradigm. The determinants and sources of inter-individual variability in different stages of drug absorption, distribution, metabolism and excretion are discussed in detail. Further, the commonly known tools for simulating ADME properties are introduced.

  4. A bottom-up route to enhance thermoelectric figures of merit in graphene nanoribbons.

    Science.gov (United States)

    Sevinçli, Hâldun; Sevik, Cem; Caın, Tahir; Cuniberti, Gianaurelio

    2013-01-01

    We propose a hybrid nano-structuring scheme for tailoring thermal and thermoelectric transport properties of graphene nanoribbons. Geometrical structuring and isotope cluster engineering are the elements that constitute the proposed scheme. Using first-principles based force constants and Hamiltonians, we show that the thermal conductance of graphene nanoribbons can be reduced by 98.8% at room temperature and the thermoelectric figure of merit, ZT, can be as high as 3.25 at T = 800 K. The proposed scheme relies on a recently developed bottom-up fabrication method, which is proven to be feasible for synthesizing graphene nanoribbons with an atomic precision.

  5. Unsupervised tattoo segmentation combining bottom-up and top-down cues

    Science.gov (United States)

    Allen, Josef D.; Zhao, Nan; Yuan, Jiangbo; Liu, Xiuwen

    2011-06-01

    Tattoo segmentation is challenging due to the complexity and large variance in tattoo structures. We have developed a segmentation algorithm for finding tattoos in an image. Our basic idea is split-merge: split each tattoo image into clusters through a bottom-up process, learn to merge the clusters containing skin and then distinguish tattoo from the other skin via top-down prior in the image itself. Tattoo segmentation with unknown number of clusters is transferred to a figureground segmentation. We have applied our segmentation algorithm on a tattoo dataset and the results have shown that our tattoo segmentation system is efficient and suitable for further tattoo classification and retrieval purpose.

  6. Integrating top-down/bottom-up sustainability strategies: an ethical challenge

    Directory of Open Access Journals (Sweden)

    John Cairns Jr.

    2003-02-01

    Full Text Available Sustainable use of the planet will require multiple sustainability strategies, which will range from the entire system, the entire Earth, the local or regional. Strategies starting at the highest system level are referred to as 'top-down', and strategies designed for components, local or regional, are referred to as 'bottom-up'. Doubtless, several intermediate levels will eventually be required, although the number is far from clear at this time. It is abundantly clear that both top-down and bottom-up strategies must be integrated effectively or neither will work well. Furthermore, there will be significant uncertainties at both levels of organisation, which will be reduced as evidence accumulates. However, sustainability is too complex and dynamic to reduce scientific uncertainty to a level desired by most decision makers. A great emphasis on sustain-ethics and value judgements will improve communications between those working at different organisational levels since humankind's wish to leave a habitable planet for its descendants and those of other life forms is clearly a value judgement.

  7. Bottom-up realization and electrical characterization of a graphene-based device

    Science.gov (United States)

    Maffucci, A.; Micciulla, F.; Cataldo, A.; Miano, G.; Bellucci, S.

    2016-03-01

    We propose a bottom-up procedure to fabricate an easy-to-engineer graphene-based device, consisting of a microstrip-like circuit where few-layer graphene nanoplatelets are used to contact two copper electrodes. The graphene nanoplatelets are obtained by the microwave irradiation of intercalated graphite, i.e., an environmentally friendly, fast and low-cost procedure. The contact is created by a bottom-up process, driven by the application of a DC electrical field in the gap between the electrodes, yielding the formation of a graphene carpet. The electrical resistance of the device has been measured as a function of the gap length and device temperature. The possible use of this device as a gas sensor is demonstrated by measuring the sensitivity of its electrical resistance to the presence of gas. The measured results demonstrate a good degree of reproducibility in the fabrication process, and the competitive performance of devices, thus making the proposed technique potentially attractive for industrial applications.

  8. Selective spatial attention modulates bottom-up informational masking of speech.

    Science.gov (United States)

    Carlile, Simon; Corkhill, Caitlin

    2015-03-02

    To hear out a conversation against other talkers listeners overcome energetic and informational masking. Largely attributed to top-down processes, information masking has also been demonstrated using unintelligible speech and amplitude-modulated maskers suggesting bottom-up processes. We examined the role of speech-like amplitude modulations in information masking using a spatial masking release paradigm. Separating a target talker from two masker talkers produced a 20 dB improvement in speech reception threshold; 40% of which was attributed to a release from informational masking. When across frequency temporal modulations in the masker talkers are decorrelated the speech is unintelligible, although the within frequency modulation characteristics remains identical. Used as a masker as above, the information masking accounted for 37% of the spatial unmasking seen with this masker. This unintelligible and highly differentiable masker is unlikely to involve top-down processes. These data provides strong evidence of bottom-up masking involving speech-like, within-frequency modulations and that this, presumably low level process, can be modulated by selective spatial attention.

  9. Top-down versus bottom-up processing of influence diagrams in probabilistic analysis

    International Nuclear Information System (INIS)

    Timmerman, R.D.; Burns, T.J.; Dodds, H.L. Jr.

    1986-01-01

    Recent work by Phillips et al and Selby et al has shown that influence diagram methodology can be a useful analytical tool in reactor safety studies. In some instances, an influence diagram can be used as a graphical representation of probabilistic dependence within a system or event sequence. Under these circumstances, Bayesian statistics is employed to transform the relationships depicted in the influence diagram into the correct expression for a desired marginal probability (e.g., the top node). In the references cited above, the authors demonstrated the usefulness of influence diagrams for assessing the reliability of operator performance during pressurized thermal shock transients. In addition, the use of influence diagrams identified the critical variables that had the greatest impact on operator reliability for a particular scenario (e.g., control room design, procedures, etc.). Top-down and bottom-up algorithms have emerged as the dominant methods for quantifying influence diagrams. The purpose of this paper is to demonstrate a potential error in employing the bottom-up algorithm when dealing with interdependencies

  10. High vacuum synthesis and ambient stability of bottom-up graphene nanoribbons.

    Science.gov (United States)

    Fairbrother, Andrew; Sanchez-Valencia, Juan-Ramon; Lauber, Beat; Shorubalko, Ivan; Ruffieux, Pascal; Hintermann, Tobias; Fasel, Roman

    2017-02-23

    Carbon-based nanomaterials such as graphene are at a crucial point in application development, and their promising potential, which has been demonstrated at the laboratory scale, must be translated to an industrial setting for commercialization. Graphene nanoribbons in particular overcome one limitation of graphene in some electronic applications because they exhibit a sizeable bandgap. However, synthesis of bottom-up graphene nanoribbons is most commonly performed under ultra-high vacuum conditions, which are costly and difficult to maintain in a manufacturing environment. Additionally, little is known about the stability of graphene nanoribbons under ambient conditions or during transfer to technologically relevant substrates and subsequent device processing. This work addresses some of these challenges, first by synthesizing bottom-up graphene nanoribbons under easily obtained high vacuum conditions and identifying water and oxygen as the residual gases responsible for interfering with proper coupling during the polymerization step. And second, by using Raman spectroscopy to probe the stability of nanoribbons during storage under ambient conditions, after transfer to arbitrary substrates, and after fabrication of field-effect transistor devices, which shows structurally intact nanoribbons even several months after synthesis. These findings demonstrate the potential of graphene nanoribbon technologies by addressing some limitations which might arise in their commercialization.

  11. Bottom-up realization and electrical characterization of a graphene-based device

    International Nuclear Information System (INIS)

    Maffucci, A; Micciulla, F; Cataldo, A; Bellucci, S; Miano, G

    2016-01-01

    We propose a bottom-up procedure to fabricate an easy-to-engineer graphene-based device, consisting of a microstrip-like circuit where few-layer graphene nanoplatelets are used to contact two copper electrodes. The graphene nanoplatelets are obtained by the microwave irradiation of intercalated graphite, i.e., an environmentally friendly, fast and low-cost procedure. The contact is created by a bottom-up process, driven by the application of a DC electrical field in the gap between the electrodes, yielding the formation of a graphene carpet. The electrical resistance of the device has been measured as a function of the gap length and device temperature. The possible use of this device as a gas sensor is demonstrated by measuring the sensitivity of its electrical resistance to the presence of gas. The measured results demonstrate a good degree of reproducibility in the fabrication process, and the competitive performance of devices, thus making the proposed technique potentially attractive for industrial applications. (paper)

  12. Carry-over effect between diet and physical activity: the bottom-up and top-down hypotheses of hierarchical self-efficacy.

    Science.gov (United States)

    Miao, Miao; Gan, Yiqun; Gan, Tingting; Zhou, Guangyu

    2017-03-01

    Healthy diet and physical activity have consistently been found to be positively correlated; however, most health behavior theories are focused on regulation of changes in single, rather than multiple, behaviors. Thus, this study explored the mechanism of the carry-over effect between diet and physical activity by conducting a longitudinal study with 706 participants to test the bottom-up and top-down hypotheses of hierarchical self-efficacy (SE). At Time 1 (baseline) and Time 3 (4 weeks after baseline), dietary behavior, physical activity, and self-efficacies of these behaviors (at the contextual level) were measured, while at Time 2 (2 weeks after baseline), general SE (at the general level) was assessed. Mediation analysis and structural equation models supported both the bottom-up and top-down hypotheses for different levels of self-efficacies, suggesting that hierarchical SE is an important factor underlying the carry-over mechanism between diet and physical activity.

  13. Self-Efficacy as a Mediator in Bottom-Up Dissemination of a Research-Supported Intervention for Young, Traumatized Children and Their Families.

    Science.gov (United States)

    David, Paula; Schiff, Miriam

    2017-01-01

    Implementation literature has under-reported bottom-up dissemination attempts of research-supported interventions (RSI). This study examined factors associated with individual clinicians' implementation of Child-Parent Psychotherapy (CPP), including CPP social network (SN), supervision, and self-efficacy. Seventy-seven (90%) CPP graduates completed a cross-sectional survey, including measures regarding social network, receiving supervision, and CPP self-efficacy. Self-efficacy was significantly associated with CPP implementation; CPP SN and supervision were not. Mediation models showed that self-efficacy significantly mediated between CPP SN and supervision, and the implementation variables. Findings illuminate the importance of supporting clinicians using a new RSI, particularly in bottom-up dissemination, in order to foster RSI self-efficacy.

  14. Canopy-scale flux measurements and bottom-up emission estimates of volatile organic compounds from a mixed oak and hornbeam forest in northern Italy

    Directory of Open Access Journals (Sweden)

    W. J. F. Acton

    2016-06-01

    Full Text Available This paper reports the fluxes and mixing ratios of biogenically emitted volatile organic compounds (BVOCs 4 m above a mixed oak and hornbeam forest in northern Italy. Fluxes of methanol, acetaldehyde, isoprene, methyl vinyl ketone + methacrolein, methyl ethyl ketone and monoterpenes were obtained using both a proton-transfer-reaction mass spectrometer (PTR-MS and a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS together with the methods of virtual disjunct eddy covariance (using PTR-MS and eddy covariance (using PTR-ToF-MS. Isoprene was the dominant emitted compound with a mean daytime flux of 1.9 mg m−2 h−1. Mixing ratios, recorded 4 m above the canopy, were dominated by methanol with a mean value of 6.2 ppbv over the 28-day measurement period. Comparison of isoprene fluxes calculated using the PTR-MS and PTR-ToF-MS showed very good agreement while comparison of the monoterpene fluxes suggested a slight over estimation of the flux by the PTR-MS. A basal isoprene emission rate for the forest of 1.7 mg m−2 h−1 was calculated using the Model of Emissions of Gases and Aerosols from Nature (MEGAN isoprene emission algorithms (Guenther et al., 2006. A detailed tree-species distribution map for the site enabled the leaf-level emission of isoprene and monoterpenes recorded using gas-chromatography mass spectrometry (GC–MS to be scaled up to produce a bottom-up canopy-scale flux. This was compared with the top-down canopy-scale flux obtained by measurements. For monoterpenes, the two estimates were closely correlated and this correlation improved when the plant-species composition in the individual flux footprint was taken into account. However, the bottom-up approach significantly underestimated the isoprene flux, compared with the top-down measurements, suggesting that the leaf-level measurements were not representative of actual emission rates.

  15. Top-down and bottom-up influences on the left ventral occipito-temporal cortex during visual word recognition: an analysis of effective connectivity.

    Science.gov (United States)

    Schurz, Matthias; Kronbichler, Martin; Crone, Julia; Richlan, Fabio; Klackl, Johannes; Wimmer, Heinz

    2014-04-01

    The functional role of the left ventral occipito-temporal cortex (vOT) in visual word processing has been studied extensively. A prominent observation is higher activation for unfamiliar but pronounceable letter strings compared to regular words in this region. Some functional accounts have interpreted this finding as driven by top-down influences (e.g., Dehaene and Cohen [2011]: Trends Cogn Sci 15:254-262; Price and Devlin [2011]: Trends Cogn Sci 15:246-253), while others have suggested a difference in bottom-up processing (e.g., Glezer et al. [2009]: Neuron 62:199-204; Kronbichler et al. [2007]: J Cogn Neurosci 19:1584-1594). We used dynamic causal modeling for fMRI data to test bottom-up and top-down influences on the left vOT during visual processing of regular words and unfamiliar letter strings. Regular words (e.g., taxi) and unfamiliar letter strings of pseudohomophones (e.g., taksi) were presented in the context of a phonological lexical decision task (i.e., "Does the item sound like a word?"). We found no differences in top-down signaling, but a strong increase in bottom-up signaling from the occipital cortex to the left vOT for pseudohomophones compared to words. This finding can be linked to functional accounts which assume that the left vOT contains neurons tuned to complex orthographic features such as morphemes or words [e.g., Dehaene and Cohen [2011]: Trends Cogn Sci 15:254-262; Kronbichler et al. [2007]: J Cogn Neurosci 19:1584-1594]: For words, bottom-up signals converge onto a matching orthographic representation in the left vOT. For pseudohomophones, the propagated signals do not converge, but (partially) activate multiple orthographic word representations, reflected in increased effective connectivity. Copyright © 2013 Wiley Periodicals, Inc.

  16. Disentangling the Role of Cortico-Basal Ganglia Loops in Top-Down and Bottom-Up Visual Attention: An Investigation of Attention Deficits in Parkinson Disease.

    Science.gov (United States)

    Tommasi, Giorgio; Fiorio, Mirta; Yelnik, Jérôme; Krack, Paul; Sala, Francesca; Schmitt, Emmanuelle; Fraix, Valérie; Bertolasi, Laura; Le Bas, Jean-François; Ricciardi, Giuseppe Kenneth; Fiaschi, Antonio; Theeuwes, Jan; Pollak, Pierre; Chelazzi, Leonardo

    2015-06-01

    It is solidly established that top-down (goal-driven) and bottom-up (stimulus-driven) attention mechanisms depend on distributed cortical networks, including prefrontal and frontoparietal regions. On the other hand, it is less clear whether the BG also contribute to one or the other of these mechanisms, or to both. The current study was principally undertaken to clarify this issue. Parkinson disease (PD), a neurodegenerative disorder primarily affecting the BG, has proven to be an effective model for investigating the contribution of the BG to different brain functions; therefore, we set out to investigate deficits of top-down and bottom-up attention in a selected cohort of PD patients. With this objective in mind, we compared the performance on three computerized tasks of two groups of 12 parkinsonian patients (assessed without any treatment), one otherwise pharmacologically treated and the other also surgically treated, with that of a group of controls. The main behavioral tool for our study was an attentional capture task, which enabled us to tap the competition between top-down and bottom-up mechanisms of visual attention. This task was suitably combined with a choice RT and a simple RT task to isolate any specific deficit of attention from deficits in motor response selection and initiation. In the two groups of patients, we found an equivalent increase of attentional capture but also comparable delays in target selection in the absence of any salient distractor (reflecting impaired top-down mechanisms) and movement initiation compared with controls. In contrast, motor response selection processes appeared to be prolonged only in the operated patients. Our results confirm that the BG are involved in both motor and cognitive domains. Specifically, damage to the BG, as it occurs in PD, leads to a distinct deficit of top-down control of visual attention, and this can account, albeit indirectly, for the enhancement of attentional capture, reflecting weakened

  17. IMI - Oral biopharmaceutics tools project - Evaluation of bottom-up PBPK prediction success part 3: Identifying gaps in system parameters by analysing In Silico performance across different compound classes.

    Science.gov (United States)

    Darwich, Adam S; Margolskee, Alison; Pepin, Xavier; Aarons, Leon; Galetin, Aleksandra; Rostami-Hodjegan, Amin; Carlert, Sara; Hammarberg, Maria; Hilgendorf, Constanze; Johansson, Pernilla; Karlsson, Eva; Murphy, Dónal; Tannergren, Christer; Thörn, Helena; Yasin, Mohammed; Mazuir, Florent; Nicolas, Olivier; Ramusovic, Sergej; Xu, Christine; Pathak, Shriram M; Korjamo, Timo; Laru, Johanna; Malkki, Jussi; Pappinen, Sari; Tuunainen, Johanna; Dressman, Jennifer; Hansmann, Simone; Kostewicz, Edmund; He, Handan; Heimbach, Tycho; Wu, Fan; Hoft, Carolin; Pang, Yan; Bolger, Michael B; Huehn, Eva; Lukacova, Viera; Mullin, James M; Szeto, Ke X; Costales, Chester; Lin, Jian; McAllister, Mark; Modi, Sweta; Rotter, Charles; Varma, Manthena; Wong, Mei; Mitra, Amitava; Bevernage, Jan; Biewenga, Jeike; Van Peer, Achiel; Lloyd, Richard; Shardlow, Carole; Langguth, Peter; Mishenzon, Irina; Nguyen, Mai Anh; Brown, Jonathan; Lennernäs, Hans; Abrahamsson, Bertil

    2017-01-01

    Three Physiologically Based Pharmacokinetic software packages (GI-Sim, Simcyp® Simulator, and GastroPlus™) were evaluated as part of the Innovative Medicine Initiative Oral Biopharmaceutics Tools project (OrBiTo) during a blinded "bottom-up" anticipation of human pharmacokinetics. After data analysis of the predicted vs. measured pharmacokinetics parameters, it was found that oral bioavailability (F oral ) was underpredicted for compounds with low permeability, suggesting improper estimates of intestinal surface area, colonic absorption and/or lack of intestinal transporter information. F oral was also underpredicted for acidic compounds, suggesting overestimation of impact of ionisation on permeation, lack of information on intestinal transporters, or underestimation of solubilisation of weak acids due to less than optimal intestinal model pH settings or underestimation of bile micelle contribution. F oral was overpredicted for weak bases, suggesting inadequate models for precipitation or lack of in vitro precipitation information to build informed models. Relative bioavailability was underpredicted for both high logP compounds as well as poorly water-soluble compounds, suggesting inadequate models for solubility/dissolution, underperforming bile enhancement models and/or lack of biorelevant solubility measurements. These results indicate areas for improvement in model software, modelling approaches, and generation of applicable input data. However, caution is required when interpreting the impact of drug-specific properties in this exercise, as the availability of input parameters was heterogeneous and highly variable, and the modellers generally used the data "as is" in this blinded bottom-up prediction approach. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Implications of the Vienna Integrated Model of Art Perception for art-based interventions in clinical populations: Comment on "Move me, astonish me... delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates" by Matthew Pelowski et al.

    Science.gov (United States)

    Taruffi, Liila; Koelsch, Stefan

    2017-07-01

    Pelowski et al. present a holistic framework within which the multiple processes underlying art viewing can be systematically organized [1]. The proposed model integrates a broad range of dynamic mechanisms, which can effectively account for empirical as well as humanistic perspectives on art perception. Particularly challenging is the final section of the article, where the authors draw a correspondence between behavioral and cognitive components and brain structures (as well as networks). Here, we comment on the implications of the Vienna Integrated Model of Art Perception for art therapy in clinical populations, particularly focusing on (1) expanding Pelowski et al.'s considerations of the Default Mode Network (DMN) into discussion of its relevance to mental diseases, and (2) elaborating on empathic resonance in aesthetic contexts and the capacity of art to build up empathic skills.

  19. Interaction of bottom-up and top-down processes in the perception of ambiguous figures.

    Science.gov (United States)

    Intaitė, Monika; Noreika, Valdas; Šoliūnas, Alvydas; Falter, Christine M

    2013-08-30

    Ambiguous figures reverse their appearance during prolonged viewing and can be perceived in two (or more) available interpretations. Both physical stimulus manipulations and cognitive control influence the perception of ambiguous figures, but the underlying mechanisms remain poorly understood. In the current study, the perception of an ambiguous figure was manipulated by adaptation to unambiguous figures and/or placing the ambiguous figure into a context of unambiguous figures. Our results indicate that both adaptation and context can effectively modulate perception of the ambiguous figure. When manipulated together, adaptation and context processes showed additive effects upon the perception of the ambiguous figure implying the independent mechanisms. Thus, top-down and bottom-up processes seem to influence the perception of the ambiguous figures independently and neither seems to be uniquely responsible for the generation of perceptual changes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Bottom-up and top-down controls on picoplankton in the East China Sea

    Science.gov (United States)

    Guo, C.; Liu, H.; Zheng, L.; Song, S.; Chen, B.; Huang, B.

    2013-05-01

    Dynamics of picoplankton population distribution in the East China Sea (ECS), a marginal sea in the western North Pacific Ocean, were studied during two "CHOICE-C" cruises in August 2009 (summer) and January 2010 (winter). Dilution experiments were conducted during the two cruises to investigate the growth and grazing among picophytoplantkon populations. Picoplankton accounted for an average of ~29% (2% to 88%) of community carbon biomass in the ECS on average, with lower percentages in plume region than in shelf and kuroshio regions. Averaged growth rates (μ) for Prochlorococcus (Pro), Synechococcus (Syn) and picoeukaryotes (peuk) were 0.36, 0.89, 0.90 d-1, respectively, in summer, and 0.46, 0.58, 0.56 d-1, respectively, in winter. Seawater salinity and nutrient availability exerted significant controls on picoplankton growth rate. Averaged grazing mortality (m) were 0.46, 0.63, 0.68 d-1 in summer, and 0.22, 0.32, 0.22 d-1 in winter for Pro, Syn and peuk respectively. The three populations demonstrated very different distribution patterns regionally and seasonally affected by both bottom-up and top-down controls. In summer, Pro, Syn and peuk were dominant in Kuroshio, transitional and plume regions respectively. Protist grazing consumed 84%, 78%, 73% and 45%, 47%, 57% of production for Pro, Syn and peuk in summer and winter respectively, suggesting more significant top-down controls in summer. In winter, all three populations tended to distribute in offshore regions, although the area of coverage was different (peuk > Syn > Pro). Bottom-up factors can explain as much as 91.5%, 82% and 81.2% of Pro, Syn and peuk abundance variance in winter, while only 59.1% and 43.7% for Pro and peuk in summer. Regionally, Yangtze River discharge plays a significant role in affecting the intensity of top-down control, indicated by significant and negative association between salinity and grazing mortality of all three populations and higher grazing mortality to growth rate ratio

  1. Bottom-up Synthesis of Porous NiMo Alloy for Hydrogen Evolution Reaction

    Directory of Open Access Journals (Sweden)

    Kailong Hu

    2018-01-01

    Full Text Available Bottom-up synthesis of porous NiMo alloy reduced by NiMoO4 nanofibers was systematically investigated to fabricate non-noble metal porous electrodes for hydrogen production. The different annealing temperatures of NiMoO4 nanofibers under hydrogen atmosphere reveal that the 950 °C annealing temperature is key for producing bicontinuous porous NiMo alloy without oxide phases. The porous NiMo alloy acts as a cathode in electrical water splitting, which demonstrates not only almost identical catalytic activity with commercial Pt/C in 1.0 M KOH solution, but also superb stability for 12 days at an electrode potential of −200 mV vs. reversible hydrogen electrode (RHE.

  2. A bottom-up route to enhance thermoelectric figures of merit in graphene nanoribbons

    DEFF Research Database (Denmark)

    Sevincli, Haldun; Sevik, Cem; Cagin, Tahir

    2013-01-01

    We propose a hybrid nano-structuring scheme for tailoring thermal and thermoelectric transport properties of graphene nanoribbons. Geometrical structuring and isotope cluster engineering are the elements that constitute the proposed scheme. Using first-principles based force constants and Hamilto......We propose a hybrid nano-structuring scheme for tailoring thermal and thermoelectric transport properties of graphene nanoribbons. Geometrical structuring and isotope cluster engineering are the elements that constitute the proposed scheme. Using first-principles based force constants...... and Hamiltonians, we show that the thermal conductance of graphene nanoribbons can be reduced by 98.8% at room temperature and the thermoelectric figure of merit, ZT, can be as high as 3.25 at T = 800 K. The proposed scheme relies on a recently developed bottom-up fabrication method, which is proven to be feasible...

  3. Unsupervised Tattoo Segmentation Combining Bottom-Up and Top-Down Cues

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Josef D [ORNL

    2011-01-01

    Tattoo segmentation is challenging due to the complexity and large variance in tattoo structures. We have developed a segmentation algorithm for nding tattoos in an image. Our basic idea is split-merge: split each tattoo image into clusters through a bottom-up process, learn to merge the clusters containing skin and then distinguish tattoo from the other skin via top-down prior in the image itself. Tattoo segmentation with unknown number of clusters is transferred to a gure-ground segmentation. We have applied our segmentation algorithm on a tattoo dataset and the results have shown that our tattoo segmentation system is e cient and suitable for further tattoo classi cation and retrieval purpose.

  4. Sequential bottom-up assembly of mechanically stabilized synthetic cells by microfluidics

    Science.gov (United States)

    Weiss, Marian; Frohnmayer, Johannes Patrick; Benk, Lucia Theresa; Haller, Barbara; Janiesch, Jan-Willi; Heitkamp, Thomas; Börsch, Michael; Lira, Rafael B.; Dimova, Rumiana; Lipowsky, Reinhard; Bodenschatz, Eberhard; Baret, Jean-Christophe; Vidakovic-Koch, Tanja; Sundmacher, Kai; Platzman, Ilia; Spatz, Joachim P.

    2018-01-01

    Compartments for the spatially and temporally controlled assembly of biological processes are essential towards cellular life. Synthetic mimics of cellular compartments based on lipid-based protocells lack the mechanical and chemical stability to allow their manipulation into a complex and fully functional synthetic cell. Here, we present a high-throughput microfluidic method to generate stable, defined sized liposomes termed `droplet-stabilized giant unilamellar vesicles (dsGUVs)’. The enhanced stability of dsGUVs enables the sequential loading of these compartments with biomolecules, namely purified transmembrane and cytoskeleton proteins by microfluidic pico-injection technology. This constitutes an experimental demonstration of a successful bottom-up assembly of a compartment with contents that would not self-assemble to full functionality when simply mixed together. Following assembly, the stabilizing oil phase and droplet shells are removed to release functional self-supporting protocells to an aqueous phase, enabling them to interact with physiologically relevant matrices.

  5. Multisegment injections improve peptide identification rates in capillary zone electrophoresis-based bottom-up proteomics.

    Science.gov (United States)

    Boley, Danielle A; Zhang, Zhenbin; Dovichi, Norman J

    2017-11-10

    While capillary zone electrophoresis (CZE) provides dramatically improved numbers of peptide identifications compared with reversed-phase chromatography for bottom-up proteomics of mass limited samples, CZE inevitably produces lower numbers of peptide identifications than RPLC for larger samples. One reason for this poorer performance is the dead time between injection of samples and subsequent appearance of the fastest moving component. This dead time is typically 25% of the separation window in CZE, but is only 5% of the separation window in gradient elution RPLC. This dead time can be eliminated in CZE by use of a multisegment injection mode where a series of samples is analyzed by injecting each sample while the preceding sample is still being separated. In this paper, we demonstrate that capillary zone electrophoresis employing sequential injections can produce a doubling in peptide identification rate with no degradation in separation efficiency. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Bottom-up control of geomagnetic secular variation by the Earth's inner core

    DEFF Research Database (Denmark)

    Aubert, Julien; Finlay, Chris; Fournier, Alexandre

    2013-01-01

    release in the outer core which in turn distorts the gyre, forcing it to become eccentric, in agreement with recent core flow inversions6, 10, 11. This bottom-up heterogeneous driving of core convection dominates top-down driving from mantle thermal heterogeneities, and localizes magnetic variations...... of geomagnetic secular variation. Here we show that it can be reproduced provided that two mechanisms relying on the inner core are jointly considered. First, gravitational coupling5 aligns the inner core with the mantle, forcing the flow of liquid metal in the outer core into a giant, westward drifting, sheet......-like gyre6. The resulting shear concentrates azimuthal magnetic flux at low latitudes close to the core–mantle boundary, where it is expelled by core convection and subsequently transported westward. Second, differential inner-core growth7, 8, fastest below Indonesia6, 9, causes an asymmetric buoyancy...

  7. Manufacturing at Nanoscale: Top-Down, Bottom-up and System Engineering

    International Nuclear Information System (INIS)

    Zhang Xiang; Sun Cheng; Fang, Nicholas

    2004-01-01

    The current nano-technology revolution is facing several major challenges: to manufacture nanodevices below 20 nm, to fabricate three-dimensional complex nano-structures, and to heterogeneously integrate multiple functionalities. To tackle these grand challenges, the Center for Scalable and Integrated NAno-Manufacturing (SINAM), a NSF Nanoscale Science and Engineering Center, set its goal to establish a new manufacturing paradigm that integrates an array of new nano-manufacturing technologies, including the plasmonic imaging lithography and ultramolding imprint lithography aiming toward critical resolution of 1-10 nm and the hybrid top-down and bottom-up technologies to achieve massively parallel integration of heterogeneous nanoscale components into higher-order structures and devices. Furthermore, SINAM will develop system engineering strategies to scale-up the nano-manufacturing technologies. SINAMs integrated research and education platform will shed light to a broad range of potential applications in computing, telecommunication, photonics, biotechnology, health care, and national security

  8. Bottom-Up Engineering of Well-Defined 3D Microtissues Using Microplatforms and Biomedical Applications.

    Science.gov (United States)

    Lee, Geon Hui; Lee, Jae Seo; Wang, Xiaohong; Lee, Sang Hoon

    2016-01-07

    During the last decades, the engineering of well-defined 3D tissues has attracted great attention because it provides in vivo mimicking environment and can be a building block for the engineering of bioartificial organs. In this Review, diverse engineering methods of 3D tissues using microscale devices are introduced. Recent progress of microtechnologies has enabled the development of microplatforms for bottom-up assembly of diverse shaped 3D tissues consisting of various cells. Micro hanging-drop plates, microfluidic chips, and arrayed microwells are the typical examples. The encapsulation of cells in hydrogel microspheres and microfibers allows the engineering of 3D microtissues with diverse shapes. Applications of 3D microtissues in biomedical fields are described, and the future direction of microplatform-based engineering of 3D micro-tissues is discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Diversity has stronger top-down than bottom-up effects on decomposition.

    Science.gov (United States)

    Srivastava, Diane S; Cardinale, Bradley J; Downing, Amy L; Duffy, J Emmett; Jouseau, Claire; Sankaran, Mahesh; Wright, Justin P

    2009-04-01

    The flow of energy and nutrients between trophic levels is affected by both the trophic structure of food webs and the diversity of species within trophic levels. However, the combined effects of trophic structure and diversity on trophic transfer remain largely unknown. Here we ask whether changes in consumer diversity have the same effect as changes in resource diversity on rates of resource consumption. We address this question by focusing on consumer-resource dynamics for the ecologically important process of decomposition. This study compares the top-down effect of consumer (detritivore) diversity on the consumption of dead organic matter (decomposition) with the bottom-up effect of resource (detrital) diversity, based on a compilation of 90 observations reported in 28 studies. We did not detect effects of either detrital or consumer diversity on measures of detrital standing stock, and effects on consumer standing stock were equivocal. However, our meta-analysis indicates that reductions in detritivore diversity result in significant reductions in the rate of decomposition. Detrital diversity has both positive and negative effects on decomposition, with no overall trend. This difference between top-down and bottom-up effects of diversity is robust to different effect size metrics and could not be explained by differences in experimental systems or designs between detritivore and detrital manipulations. Our finding that resource diversity has no net effect on consumption in "brown" (detritus-consumer) food webs contrasts with previous findings from "green" (plant-herbivore) food webs and suggests that effects of plant diversity on consumption may fundamentally change after plant death.

  10. Mineralization of Synthetic Polymer Scaffolds: A Bottom-upApproach for the Development of Artificial Bone

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jie; Viengkham, Malathong; Bertozzi, Carolyn R.

    2004-09-27

    The controlled integration of organic and inorganic components confers natural bone with superior mechanical properties. Bone biogenesis is thought to occur by templated mineralization of hard apatite crystals by an elastic protein scaffold, a process we sought to emulate with synthetic biomimetic hydrogel polymers. Crosslinked polymethacrylamide and polymethacrylate hydrogels were functionalized with mineral-binding ligands and used to template the formation of hydroxyapatite. Strong adhesion between the organic and inorganic materials was achieved for hydrogels functionalized with either carboxylate or hydroxy ligands. The mineral-nucleating potential of hydroxyl groups identified here broadens the design parameters for synthetic bone-like composites and suggests a potential role for hydroxylated collagen proteins in bone mineralization.

  11. Acoustic Metamaterials Through a Microfluidic, Bottom-up Approach: Toward Highly Attenuating, Negative Effective Density Materials

    Science.gov (United States)

    2012-10-01

    RECHERCHE SCIENTIFIQUE (CNRS) 1, Esplanade Des Arts et Metiers Talence 33400 France EOARD SPC 11-4006 Report Date: October 2012 Final Report...CTRE NAT DE LA RECHERCHE SCIENTIFIQUE (CNRS) 1, Esplanade Des Arts et Metiers Talence 33400 France N/A European Office of Aerospace Research and

  12. A Bottom-Up Approach investigating the Potential Impacts of Ethanol in Atmospheric Waters

    Science.gov (United States)

    Mead, R. N.; Taylor, A.; Shimizu, M. S.; Avery, B.; Kieber, R. J.; Willey, J. D.

    2017-12-01

    Ethanol, an emerging biofuel primarily derived from corn, can enter the atmosphere through incomplete combustion as well as natural emissions. There is a paucity of knowledge on the impacts of ethanol with other organic compounds in atmospheric waters. In this study, Guaiacol (2-methoxy phenol) was chosen as a proxy to investigate photolytic reactions with ethanol in rainwater with subsequent measurements of optical properties and chemical composition. Solutions with equimolar concentrations of guaiacol, ethanol, and hydrogen peroxide (pH 4.5 deionized water) were reacted in artificial sunlight for 6 hours. Solutions kept in the dark over this time showed no change in absorbance while solutions exposed to light (without and with ethanol) had increases in absorbance indicating formation of new chromophoric compounds. Although, little difference was observed optically and by GC/MS between solutions prepared without and with ethanol, the rate of guaiacol loss decreased with ethanol present, suggesting that ethanol could act as a radical scavenger. To simulate more polluted air masses, NaNO2 was added to each reaction mixture to observe further changes. The presence of NaNO2 led to larger increases in absorbance than in earlier experiments. No differences were observed between non-ethanol and ethanol containing solutions both optically and when run by GC-MS. Following irradiation experiments, solutions were placed in the dark and allowed to react for prolonged periods of time. After a week, solutions prepared with ethanol exhibited higher absorbance than samples without added ethanol. This was the case for trials carried out in simulated clean air masses as well as ones carried out with NaNO2.

  13. Can we reach Pareto optimal outcomes using bottom-up approaches?

    NARCIS (Netherlands)

    V. Sanchez-Anguix (Victor); R. Aydoğan (Reyhan); T. Baarslag (Tim); C.M. Jonker (Catholijn)

    2016-01-01

    textabstractClassically, disciplines like negotiation and decision making have focused on reaching Pareto optimal solutions due to its stability and efficiency properties. Despite the fact that many practical and theoretical algorithms have successfully attempted to provide Pareto optimal solutions,

  14. One Thousand Flowers in Delft : A Bottom-up approach to improve teaching international students

    NARCIS (Netherlands)

    Brummelink, M.L.; Frantzeskaki, N.; Klaassen, R.G.; Blom, E.M.; Kooij, R.E.; Kroesen, J.O.; Stadler, D.I.; Van den Boogaard, M.E.D.

    2009-01-01

    Delft University of Technology (DUT) is becoming more and more an international community. Since lectures on master level are all conducted in English, the numbers of students from foreign countries attending DUT are rising and international cooperation within educational projects is a necessity. To

  15. One Thousand Flowers in Delft: A Bottom-up approach to improve teaching international students

    NARCIS (Netherlands)

    Brummelink, M.L.; Frantzeskaki, N.; Klaassen, R.G.; Blom, E.M.; Kooij, R.E.; Kroesen, J.O.; Stadler D.I.; Boogaard, M.E.D. van den

    2009-01-01

    Delft University of Technology (DUT) is becoming more and more an international community. Since lectures on master level are all conducted in English, the numbers of students from foreign countries attending DUT are rising and international cooperation within educational projects is a necessity. To

  16. Reconstitution of the activity of RND efflux pumps: a "bottom-up" approach.

    Science.gov (United States)

    Puvanendran, Dhenesh; Cece, Quentin; Picard, Martin

    2017-12-05

    Efflux pumps are systems devoted to the extrusion of noxious compounds. In this review, we discuss the various strategies that have thus far been undertaken for the investigation of efflux pumps after reconstitution into liposomes. It is challenging to uncover mechanisms and dynamics of efflux pumps due to a number of characteristics: their function depends on the correct assembly of three components and they span two adjacent membranes whose lipid compositions are very different. In addition, efflux pumps are active transporters that need energy to work. We present possible lines of improvement for the study of such systems and provide insights into future goals and challenges of efflux pump reconstitution and transport. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  17. Islands of sustainability: a bottom-up approach towards sustainable development

    OpenAIRE

    H P Wallner; M Narodoslawsky; F Moser

    1996-01-01

    In this paper we introduce the concept of 'islands of sustainability'. The basic assumption is that the development towards sustainability can be introduced starting from sustainable 'islands'. An island is an area where sustainability is reached at a local or regional level. Exchange activities within the regional network and with the environment are key points in creating an island of sustainability. One of the main theses is that the concept of sustainabiity addresses not only the interact...

  18. Integrated bottom up and top down approach to optimization of the extrusion process

    NARCIS (Netherlands)

    Vaneker, Thomas H.J.; Koenis, P.T.G.; van Ouwerkerk, Gijs; van Ouwerkerk, Gijs; Nilsen, K.E.; van Houten, Frederikus J.A.M.

    2008-01-01

    Boal BV and the University of Twente participate in research projects focused on improvement of die design methods for aluminum extrusion dies. Within this research empirical knowledge is combined with insights gained from numerical process simulations. Design rules for improvements to the geometry

  19. A bottom-up approach to technological development and its management implications in a commercial fishery

    DEFF Research Database (Denmark)

    Eigaard, Ole Ritzau

    2009-01-01

    Analyses of electronic equipment on board Danish trawlers and gillnetters show that newer, larger vessels have a significantly higher "technological level" than older, smaller vessels. A hypothesis of linkage between fish-finding and navigation technology on board and standard vessel characterist......Analyses of electronic equipment on board Danish trawlers and gillnetters show that newer, larger vessels have a significantly higher "technological level" than older, smaller vessels. A hypothesis of linkage between fish-finding and navigation technology on board and standard vessel...... plans, older, smaller vessels of a fleet are often replaced with newer, larger vessels within a fixed or reduced nominal capacity limit (e.g. total fleet tonnage), but according to the findings presented, nominal capacity reduction in fleet level may be undermined by increases in individual vessel...

  20. GramHealth: a bottom-up approach to provide preventive healthcare services for unreached community.

    Science.gov (United States)

    Ahmed, Ashir; Kabir, Lutfe; Kai, Eiko; Inoue, Sozo

    2013-01-01

    Insufficient healthcare facilities and unavailability of medical experts in rural areas are the two major reasons that kept the people unreached to healthcare services. Recent penetration of mobile phone and the demand to basic healthcare services, remote health consultancy over mobile phone became popular in developing countries. In this paper, we introduce two such representative initiatives from Bangladesh and discuss the technical challenges they face to serve a remote patient. To solve these issues, we have prototyped a box with necessary diagnostic tools, we call it a "portable clinic" and a software tool, "GramHealth" for managing the patient information. We carried out experiments in three villages in Bangladesh to observe the usability of the portable clinic and verify the functionality of "GramHealth". We display the qualitative analysis of the results obtained from the experiment. GramHealth DB has a unique combination of structured, semi-structured and un-structured data. We are currently looking at these data to see whether these can be treated as BigData and if yes, how to analyze the data and what to expect from these data to make a better clinical decision support.

  1. A Bottom-Up Approach to Teaching Robotics and Mechatronics to Mechanical Engineers

    Science.gov (United States)

    Shiller, Z.

    2013-01-01

    This paper describes a multidisciplinary teaching program, designed to provide students with the broad knowledge and skills required to practice product development in robotics and mechatronics. The curriculum was designed to prepare students for the senior capstone design project, in which they design and build a working mechatronic/robotic…

  2. Computer assistance in femoral derotation osteotomy: a bottom-up approach

    Directory of Open Access Journals (Sweden)

    Auer Christoph

    2016-09-01

    Full Text Available Severe gait abnormalities in patients with cerebral palsy are often treated by correction osteotomy. The established procedure of femoral derotation osteotomy (FDO has proven effective to realign femur anteversion. Nevertheless, studies have revealed that therapy outcome is subject to substantial inter-patient variability and systematic loss of correction. Our previous work suggests that practical limitations in FDO may significantly contribute to this effect. In this work, we propose a novel computer assisted measurement system to support FDO with objective measurement (desired accuracy: ∼ ± 3° and continuous monitoring of derotation. A prototype system based on the clinically emerging electromagnetic tracking technology is demonstrated which incorporates technical and operational considerations to enable continuous measurement in OR conditions while preserving the conventional workflow without disruptions. In phantom studies, the achieved measurement accuracy (standard error ≅±1.6∘$\\cong\\pm 1.6{}^{\\circ}$ proved high potential and may hugely benefit the quality of surgical execution. Currently, the prototype system is assessed under OR conditions in an in-vivo study with CP patients. Early experience shows high appreciation among surgeons and good potential for future application.

  3. A bottom-up approach to automatically configured Tango control systems

    International Nuclear Information System (INIS)

    Rubio-Manrique, S.; Beltran, D.; Costa, I.; Fernandez-Carreiras, D.; Gigante, J.V.; Klora, J.; Matilla, O.; Ranz, R.; Ribas, J.; Sanchez, O.

    2012-01-01

    Alba is the first synchrotron light source built in Spain. Most of Alba control system has been developed on top of Tango control system. An amount of 5531 devices are controlled in Alba accelerators (linac, booster and storage ring) using 150 Linux PCs. Alba maintains a central repository, so called 'Cabling and Controls database' (CCDB), which keeps the inventory of equipment, cables, connections and their configuration and technical specifications. The valuable information kept in this MySQL database enables some tools to automatically create and configure Tango devices and other software components of the control systems of Accelerators, beamlines and laboratories. This paper describes the process involved in this automatic setup

  4. Stepwise modularization in the construction industry using a bottom-up approach

    DEFF Research Database (Denmark)

    Kudsk, Anders; Grønvold, Martin O'Brien; Olsen, Magnus Holo

    2013-01-01

    in order to guide the entire construction process. NCC Skakt standardized their shafts by studying apartments already constructed and extracting different archetypes of toilets and kitchens. Much information was gathered, which was fed into a Product Variant Master, so that an overview could be achieved...

  5. Bottom-up politics: an agency-centred approach to globalization

    NARCIS (Netherlands)

    Kostovicova, D.; Glasius, M.

    2011-01-01

    The writing out of agency from the study of globalization resulted in its portrayal as an uncontrollable, unstoppable and unchangeable force. Ordinary people have been conceptualized as victims or beneficiaries. Alternatively, grassroots activism has been romantically portrayed as an unproblematic

  6. Renewable energy law in the EU : Legal perspectives on bottom-up approaches

    NARCIS (Netherlands)

    Peeters, Marjan; Schomerus, Thomas

    2014-01-01

    This book examines the role played by regional authorities in the EU in the transition towards renewable energy. Regional governments generally have important decision-making powers concerning energy transition, but they may encounter resistance to the establishment of renewable energy activities in

  7. Improving the success of bottom-up development work by acknowledging the dynamics among stakeholders: a case study from an Engineers Without Borders water supply project in Tenganan, Indonesia.

    Science.gov (United States)

    Bowen, J; Acciaioli, G

    2009-01-01

    This paper presents a model of development action synthesising the development arena framework with collective action theory. It shows how application of this model in the Engineers Without Borders Australia (EWB) water supply improvement and capacity building project in Tenganan, Indonesia has helped to maximise the extent to which the project practice can reflect the project rhetoric as "bottom-up" or community-inspired. The model posits a broad range of stakeholders actively engaged in development action: each stakeholder is different, with its own interests, missions, procedures, and ways of deploying power in development action. Recognising the multiplicity of subjects of development is especially crucial for improving bottom-up practice. Connections and interactions among stakeholders are inherently problematic, and must be negotiated to accomplish development work, as tensions in the dynamic among stakeholders may operate to restrict the success of these "bottom-up" development projects.

  8. Beauty and sublime. Comment on "Move me, astonish me…" delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates; by Matthew Pelowski et al.

    Science.gov (United States)

    Perlovsky, Leonid

    2017-07-01

    The VIMAP model presented in this review [1] is an interesting and detailed model of neural mechanisms of aesthetic perception. In this Comment I address one deficiency of this model: it does not address in details the fundamental notions of the VIMAP, beauty and sublime. In this regard VIMAP is similar to other publications on aesthetics.

  9. A comparative 'bottom up' proteomics strategy for the site-specific identification and quantification of protein modifications by electrophilic lipids.

    Science.gov (United States)

    Han, Bingnan; Hare, Michael; Wickramasekara, Samanthi; Fang, Yi; Maier, Claudia S

    2012-10-22

    We report a mass spectrometry-based comparative "bottom up" proteomics approach that combines d(0)/d(4)-succinic anhydride labeling with commercially available hydrazine (Hz)-functionalized beads (Affi-gel Hz beads) for detection, identification and relative quantification of site-specific oxylipid modifications in biological matrices. We evaluated and applied this robust and simple method for the quantitative analysis of oxylipid protein conjugates in cardiac mitochondrial proteome samples isolated from 3- and 24-month-old rat hearts. The use of d(0)/d(4)-succinic anhydride labeling, Hz-bead based affinity enrichment, nanoLC fractionation and MALDI-ToF/ToF tandem mass spectrometry yielded relative quantification of oxylipid conjugates with residue-specific modification information. Conjugation of acrolein (ACR), 4-hydroxy-2-hexenal (HHE), 4-hydroxy-2-nonenal (HNE) and 4-oxo-2-noneal (ONE) to cysteine, histidine and lysine residues were identified. HHE conjugates were the predominant subset of Michael-type adducts detected in this study. The HHE conjugates showed higher levels in mitochondrial preparations from young heart congruent with previous findings by others that the n-3/n-6 PUFA ratio is higher in young heart mitochondrial membranes. Although this study focuses on protein adducts of reactive oxylipids, the method might be equally applicable to protein carbonyl modifications caused by metal catalyzed oxidation reactions. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. The Impact of Bottom-Up Parking Information Provision in a Real-Life Context: The Case of Antwerp

    Directory of Open Access Journals (Sweden)

    Geert Tasseron

    2017-01-01

    Full Text Available A number of studies have analyzed the possible impacts of bottom-up parking information or parking reservation systems on parking dynamics in abstract simulation environments. In this paper, we take these efforts one step further by investigating the impacts of these systems in a real-life context: the center of the city of Antwerp, Belgium. In our simulation, we assume that all on-street and off-street parking places are equipped with technology able to transmit their occupancy status to so-called smart cars, which can receive information and reserve a parking place. We employ PARKAGENT, an agent-based simulation model, to simulate the behavior of smart and regular cars. We obtain detailed data on parking demand from FEATHERS, an activity-based transport model. The simulation results show that parking information and reservation hardly impact search time but do reduce walking distance for smart cars, leading to a reduction in total parking time, that is, the sum of search time and walking time. Reductions in search time occur only in zones with high occupancy rates, while a drop in walking distance is especially observed in low occupancy areas. Societal benefits of parking information and reservation are limited, because of the low impact on search time and the possible negative health effects of reduced walking distance.

  11. The case for refining bottom-up methane emission inventories using top-down measurements

    Science.gov (United States)

    Kelly, Bryce F. J.; Iverach, Charlotte P.; Ginty, Elisa; Bashir, Safdar; Lowry, Dave; Fisher, Rebecca E.; France, James L.; Nisbet, Euan G.

    2017-04-01

    Bottom-up global methane emission estimates are important for guiding policy development and mitigation strategies. Such inventories enable rapid and consistent proportioning of emissions by industrial sectors and land use at various scales from city to country to global. There has been limited use of top-down measurements to guide refining emission inventories. Here we compare the EDGAR gridmap data version 4.2 with over 5000 km of daytime ground level mobile atmospheric methane surveys in eastern Australia. The landscapes and industries surveyed include: urban environments, dryland farming, intensive livestock farming (both beef and lamb), irrigation agriculture, open cut and underground coal mining, and coal seam gas production. Daytime mobile methane surveys over a 2-year period show that at the landscape scale there is a high level of repeatability for the mole fraction of methane measured in the ground level atmosphere. Such consistency in the mole fraction of methane indicates that these data can be used as a proxy for flux. A scatter plot of the EDGAR emission gridmap Log[ton substance / 0.1 degree x 0.1 degree / year] versus the median mole fraction of methane / 0.1 degree x 0.1 degree in the ground level atmosphere highlights that the extent of elevated methane emissions associated with coal mining in the Hunter coalfields, which covers an area of 56 km by 24 km, has been under-represented in the EDGAR input data. Our results also show that methane emissions from country towns (population < 100,000) are underestimated in the EDGAR inventory. This is possibly due to poor information on the extent of urban gas leaks. Given the uncertainties associated with the base land use and industry data for each country, we generalise the Australian observations to the global inventory with caution. The extensive comparison of top-down measurements versus the EDGAR version 4.2 methane gridmaps highlights the need for adjustments to the base resource data and/or the

  12. Merging Bottom-Up with Top-Down: Continuous Lamellar Networks and Block Copolymer Lithography

    Science.gov (United States)

    Campbell, Ian Patrick

    Block copolymer lithography is an emerging nanopatterning technology with capabilities that may complement and eventually replace those provided by existing optical lithography techniques. This bottom-up process relies on the parallel self-assembly of macromolecules composed of covalently linked, chemically distinct blocks to generate periodic nanostructures. Among the myriad potential morphologies, lamellar structures formed by diblock copolymers with symmetric volume fractions have attracted the most interest as a patterning tool. When confined to thin films and directed to assemble with interfaces perpendicular to the substrate, two-dimensional domains are formed between the free surface and the substrate, and selective removal of a single block creates a nanostructured polymeric template. The substrate exposed between the polymeric features can subsequently be modified through standard top-down microfabrication processes to generate novel nanostructured materials. Despite tremendous progress in our understanding of block copolymer self-assembly, continuous two-dimensional materials have not yet been fabricated via this robust technique, which may enable nanostructured material combinations that cannot be fabricated through bottom-up methods. This thesis aims to study the effects of block copolymer composition and processing on the lamellar network morphology of polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) and utilize this knowledge to fabricate continuous two-dimensional materials through top-down methods. First, block copolymer composition was varied through homopolymer blending to explore the physical phenomena surrounding lamellar network continuity. After establishing a framework for tuning the continuity, the effects of various processing parameters were explored to engineer the network connectivity via defect annihilation processes. Precisely controlling the connectivity and continuity of lamellar networks through defect engineering and

  13. Which brain networks related to art perception are we talking about?. Comment on "Move me, astonish me…" delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates; by Matthew Pelowski et al.

    Science.gov (United States)

    Ayala, Francisco J.; Cela-Conde, Camilo J.

    2017-07-01

    The proposal by the Vienna Integrated Model of Art Perception (Pelowski et al., [4]; VIMAP, hereafter) is a valuable and much needed attempt to summarize and understand the cognitive processes underlying art perception. Very important in their model is, as expected, to ascertain the psychological and brain processes correlated with the perception of beauty in art works. In this commentary we'll focus exclusively on the consideration of VIMAP's section 5, ;Model stages and corresponding areas of the brain.; We'll examine the evidence advanced by VIMAP in the section about brain networks related to the perception of art.

  14. Innovative Sol-Gel Routes for the Bottom-up Preparation of Heterogeneous Catalysts.

    Science.gov (United States)

    Debecker, Damien P

    2017-12-11

    Heterogeneous catalysts can be prepared by different methods offering various levels of control on the final properties of the solid. In this account, we exemplify bottom-up preparation routes that are based on the sol-gel chemistry and allow to tailor some decisive properties of solid catalysts. First, an emulsion templating strategy is shown to lead to macrocellular self-standing monoliths with a macroscopic 3D structure. The latter can be used as catalyst or catalyst supports in flow chemistry, without requiring any subsequent shaping step. Second, the aerosol-assisted sol-gel process allows for the one-step and continuous production of porous mixed oxides. Tailored textural properties can be obtained together with an excellent control on composition and homogeneity. Third, the application of non-hydrolytic sol-gel routes, in the absence of water, leads to mixed oxides with outstanding textural properties and with peculiar surface chemistry. In all cases, the resulting catalytic performance can be correlated with the specificities of the preparation routes presented. This is exemplified in catalytic reactions in the fields of biomass conversion, petro chemistry, enantioselective organic synthesis, and air pollution mitigation. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Two Paths to Transforming Markets through Public Sector EnergyEfficiency: Bottom Up versus Top Down

    Energy Technology Data Exchange (ETDEWEB)

    Van Wie McGrory, Laura; Coleman, Philip; Fridley, David; Harris,Jeffrey; Villasenor Franco, Edgar

    2006-05-10

    The evolution of government purchasing initiatives in Mexicoand China, part of the PEPS (Promoting an Energy-efficient Public Sector)program, demonstrates the need for flexibility in designingenergy-efficiency strategies in the public sector. Several years ofpursuing a top-down (federally led) strategy in Mexico produced fewresults, and it was not until the program was restructured in 2004 tofocus on municipal-level purchasing that the program gained momentum.Today, a new partnership with the Mexican federal government is leadingto an intergovernmental initiative with strong support at the federallevel. By contrast, the PEPS purchasing initiative in China wassuccessfully initiated and led at the central government level withstrategic support from international experts. The very different successtrajectories in these two countries provide valuable lessons fordesigning country-specific public sector energy-efficiency initiatives.Enabling conditions for any successful public sector purchasinginitiative include the existence of mandatory energy-efficiencyperformance standards, an effective energy-efficiency endorsementlabeling program, an immediate need for energy conservation, a simplepilot phase (focusing on a limited number of strategically chosenproducts), and specialized technical assistance. Top-down purchasingprograms are likely to be more successful where there is high-levelpolitical endorsement and a national procurement law in place, supportedby a network of trained purchasers. Bottom-up (municipally led)purchasing programs require that municipalities have the authority to settheir own purchasing policies, and also benefit from existing networks ofcities, supported by motivated municipal leaders and trained purchasingofficials.

  16. Top-down and bottom-up regulation of macroalgal community structure on a Kenyan reef

    Science.gov (United States)

    Mörk, Erik; Sjöö, Gustaf Lilliesköld; Kautsky, Nils; McClanahan, Tim R.

    2009-09-01

    Top-down and bottom-up regulation in the form of grazing by herbivores and nutrient availability are important factors governing macroalgal communities in the coral reef ecosystem. Today, anthropogenic activities, such as over-harvesting of herbivorous fish and sea urchins and increased nutrient loading, are altering the interaction of these two structuring forces. The present study was conducted in Kenya and investigates the relative importance of herbivory and nutrient loading on macroalgal community dynamics, by looking at alterations in macroalgal functional groups, species diversity ( H') and biomass within experimental quadrats. The experiment was conducted in situ for 42 days during the dry season. Cages excluding large herbivorous fish and sea urchins were used in the study and nutrient addition was conducted using coated, slow-release fertilizer (nitrogen and phosphorous) at a site where herbivory is generally low and nutrient levels are relatively high for the region. Nutrient addition increased tissue nutrient content in the algae, and fertilized quadrats had 24% higher species diversity. Herbivore exclusion resulted in a 77% increase in algal biomass, mainly attributable to a >1000% increase in corticated forms. These results are in accordance with similar studies in other regions, but are unique in that they indicate that, even when prevailing nutrient levels are relatively high and herbivore pressure is relatively low, continued anthropogenic disturbance results in further ecological responses and increased reef degradation.

  17. Bottom-up synthesis of nitrogen-doped graphene sheets for ultrafast lithium storage.

    Science.gov (United States)

    Tian, Lei-Lei; Wei, Xian-Yong; Zhuang, Quan-Chao; Jiang, Chen-Hui; Wu, Chao; Ma, Guang-Yao; Zhao, Xing; Zong, Zhi-Min; Sun, Shi-Gang

    2014-06-07

    A facile bottom-up strategy was developed to fabricate nitrogen-doped graphene sheets (NGSs) from glucose using a sacrificial template synthesis method. Three main types of nitrogen dopants (pyridinic, pyrrolic and graphitic nitrogens) were introduced into the graphene lattice, and an inimitable microporous structure of NGS with a high specific surface area of 504 m(2) g(-1) was obtained. Particularly, with hybrid features of lithium ion batteries and Faradic capacitors at a low rate and features of Faradic capacitors at a high rate, the NGS presents a superior lithium storage performance. During electrochemical cycling, the NGS electrode afforded an enhanced reversible capacity of 832.4 mA h g(-1) at 100 mA g(-1) and an excellent cycling stability of 750.7 mA h g(-1) after 108 discharge-charge cycles. Furthermore, an astonishing rate capability of 333 mA h g(-1) at 10,000 mA g(-1) and a high rate cycle performance of 280.6 mA h g(-1) even after 1200 cycles were also achieved, highlighting the significance of nitrogen doping on the maximum utilization of graphene-based materials for advanced lithium storage.

  18. Um Modelo de inovação bottom up: Museu de Favela (MUF

    Directory of Open Access Journals (Sweden)

    Natália Nakano

    2013-12-01

    Full Text Available Este artigo tem como objetivo apresentar, descrever e discutir o modelo de inovação do primeiro museu territorial ao ar livre, concebido em uma favela no Rio de Janeiro, o Museu de Favela (MUF. Nele são introduzidos os conceitos de favela, e diferenciados museu tradicional e os ecomuseus, a fim de contextualizar o universo do MUF. Discute-se o conceito de coleção de um museu territorial ao ar livre e como se dá o trabalho de curadoria nesse contexto, bem como os tipos de interação possíveis com a diversidade de indivíduos atendidos por um museu como o MUF. Discute-se ainda o papel dessa nova tipologia museológica na sociedade, a partir de entidades criadas pela inovação do tipo bottom up realizada pela iniciativa do MUF dentro da nova museologia de ação. Conclui-se com considerações a respeito da mudança de foco do papel desempenhado pelo MUF como agente de desenvolvimento social e cultural.

  19. Bottom-Up Two-Dimensional Electron-Capture Dissociation Mass Spectrometry of Calmodulin

    Science.gov (United States)

    Floris, Federico; van Agthoven, Maria A.; Chiron, Lionel; Wootton, Christopher A.; Lam, Pui Yiu Yuko; Barrow, Mark P.; Delsuc, Marc-André; O'Connor, Peter B.

    2018-01-01

    Two-dimensional mass spectrometry (2D MS) is a tandem mass spectrometry technique that allows data-independent fragmentation of all precursors in a mixture without previous isolation, through modulation of the ion cyclotron frequency in the ICR-cell prior to fragmentation. Its power as an analytical technique has been proven particularly for proteomics. Recently, a comparison study between 1D and 2D MS has been performed using infrared multiphoton dissociation (IRMPD) on calmodulin (CaM), highlighting the capabilities of the technique in both top-down (TDP) and bottom-up proteomics (BUP). The goal of this work is to expand this study on CaM using electron-capture dissociation (ECD) 2D MS as a single complementary BUP experiment in order to enhance the cleavage coverage of the protein under analysis. By adding the results of the BUP 2D ECD MS to the 2D IRMPD MS analysis of CaM, the total cleavage coverage increased from 40% to 68%. [Figure not available: see fulltext.

  20. Sensitivity quantification of airport concrete pavement stress responses associated with top-down and bottom-up cracking

    Directory of Open Access Journals (Sweden)

    Adel Rezaei-Tarahomi

    2017-09-01

    Full Text Available The Federal Aviation Administration’s (FAA’s rigid pavement design standard employs the NIKE3D-FAA software to compute critical pavement responses of concrete airport pavement structures. NIKE3D-FAA is a modification of the original NIKE3D three-dimensional finite element analysis program developed by the Lawrence Livermore National Laboratory (LLNL of the U.S. Department of Energy, and is currently used in the FAA’s FAARFIELD program. This study evaluated the sensitivity of NIKE3D-FAA rigid pavement responses with respect to top-down and bottom-up cracking. The analysis was conducted by positioning a Boeing 777-300ER (B777-300ERaircraft at different locations (interior, corner, and edge of slab as baseline while varying other NIKE3D-FAA inputs, including rigid pavement geometric features, mechanical properties of paving and foundation materials, equivalent temperature gradient and thermal coefficient of Portland Cement Concrete (PCC layers. Several sensitivity charts were developed by examining the sensitivity of critical pavement responses to each input variation. Sensitivity evaluations were performed using a normalized sensitivity index (NSI as the quantitative metric. Using such sensitivity evaluation, the most significant NIKE3D-FAA input parameters for generating an effective synthetic database that will lower computational cost for future modeling developments were identified. Keywords: Sensitivity analysis, Airfield concrete pavement, Finite element analysis, Top down cracking

  1. Altered top-down and bottom-up processing of fear conditioning in panic disorder with agoraphobia.

    Science.gov (United States)

    Lueken, U; Straube, B; Reinhardt, I; Maslowski, N I; Wittchen, H-U; Ströhle, A; Wittmann, A; Pfleiderer, B; Konrad, C; Ewert, A; Uhlmann, C; Arolt, V; Jansen, A; Kircher, T

    2014-01-01

    Although several neurophysiological models have been proposed for panic disorder with agoraphobia (PD/AG), there is limited evidence from functional magnetic resonance imaging (fMRI) studies on key neural networks in PD/AG. Fear conditioning has been proposed to represent a central pathway for the development and maintenance of this disorder; however, its neural substrates remain elusive. The present study aimed to investigate the neural correlates of fear conditioning in PD/AG patients. The blood oxygen level-dependent (BOLD) response was measured using fMRI during a fear conditioning task. Indicators of differential conditioning, simple conditioning and safety signal processing were investigated in 60 PD/AG patients and 60 matched healthy controls. Differential conditioning was associated with enhanced activation of the bilateral dorsal inferior frontal gyrus (IFG) whereas simple conditioning and safety signal processing were related to increased midbrain activation in PD/AG patients versus controls. Anxiety sensitivity was associated positively with the magnitude of midbrain activation. The results suggest changes in top-down and bottom-up processes during fear conditioning in PD/AG that can be interpreted within a neural framework of defensive reactions mediating threat through distal (forebrain) versus proximal (midbrain) brain structures. Evidence is accumulating that this network plays a key role in the aetiopathogenesis of panic disorder.

  2. Construction of mammographic examination process ontology using bottom-up hierarchical task analysis.

    Science.gov (United States)

    Yagahara, Ayako; Yokooka, Yuki; Jiang, Guoqian; Tsuji, Shintarou; Fukuda, Akihisa; Nishimoto, Naoki; Kurowarabi, Kunio; Ogasawara, Katsuhiko

    2018-03-01

    Describing complex mammography examination processes is important for improving the quality of mammograms. It is often difficult for experienced radiologic technologists to explain the process because their techniques depend on their experience and intuition. In our previous study, we analyzed the process using a new bottom-up hierarchical task analysis and identified key components of the process. Leveraging the results of the previous study, the purpose of this study was to construct a mammographic examination process ontology to formally describe the relationships between the process and image evaluation criteria to improve the quality of mammograms. First, we identified and created root classes: task, plan, and clinical image evaluation (CIE). Second, we described an "is-a" relation referring to the result of the previous study and the structure of the CIE. Third, the procedural steps in the ontology were described using the new properties: "isPerformedBefore," "isPerformedAfter," and "isPerformedAfterIfNecessary." Finally, the relationships between tasks and CIEs were described using the "isAffectedBy" property to represent the influence of the process on image quality. In total, there were 219 classes in the ontology. By introducing new properties related to the process flow, a sophisticated mammography examination process could be visualized. In relationships between tasks and CIEs, it became clear that the tasks affecting the evaluation criteria related to positioning were greater in number than those for image quality. We developed a mammographic examination process ontology that makes knowledge explicit for a comprehensive mammography process. Our research will support education and help promote knowledge sharing about mammography examination expertise.

  3. Cyclization of the N-Terminal X-Asn-Gly Motif during Sample Preparation for Bottom-Up Proteomics

    DEFF Research Database (Denmark)

    Zhang, Xumin; Højrup, Peter

    2010-01-01

    We, herein, report a novel -17 Da peptide modification corresponding to an N-terminal cyclization of peptides possessing the N-terminal motif of X-Asn-Gly. The cyclization occurs spontaneously during sample preparation for bottom-up proteomics studies. Distinct from the two well-known N...

  4. Using classic methods in a networked manner: seeing volunteered spatial information in a bottom-up fashion

    NARCIS (Netherlands)

    Carton, L.J.; Ache, P.M.

    2014-01-01

    Using new social media and ICT infrastructures for self-organization, more and more citizen networks and business sectors organize themselves voluntarily around sustainability themes. The paper traces and evaluates one emerging innovation in such bottom-up, networked form of sustainable

  5. Leadership for Quality University Teaching: How Bottom-Up Academic Insights Can Inform Top-Down Leadership

    Science.gov (United States)

    Scott, Donald E.; Scott, Shelleyann

    2016-01-01

    This paper presents the leadership implications from a study that explored how to increase the quality of teaching in a university thereby presenting data from the bottom up--the academic perspective--to inform leadership, policies, and academic development which generally flows from the top down. We report academics' perceptions of and…

  6. Evaluating the Resilience of the Bottom-up Method used to Detect and Benchmark the Smartness of University Campuses

    NARCIS (Netherlands)

    Giovannella, Carlo; Andone, Diana; Dascalu, Mihai; Popescu, Elvira; Rehm, Matthias; Mealha, Oscar

    2017-01-01

    A new method to perform a bottom-up extraction and benchmark of the perceived multilevel smartness of complex ecosystems has been recently described and applied to territories and learning ecosystems like university campuses and schools. In this paper we study the resilience of our method

  7. Bottom-up estimation of joint moments during manual lifting using orientation sensors instead of position sensors

    NARCIS (Netherlands)

    Faber, G.S.; Kingma, I.; van Dieen, J.H.

    2010-01-01

    L5/S1, hip and knee moments during manual lifting tasks are, in a laboratory environment, frequently established by bottom-up inverse dynamics, using force plates to measure ground reaction forces (GRFs) and an optoelectronic system to measure segment positions and orientations. For field

  8. Two-dimensional combinatorial screening enables the bottom-up design of a microRNA-10b inhibitor.

    Science.gov (United States)

    Velagapudi, Sai Pradeep; Disney, Matthew D

    2014-03-21

    The RNA motifs that bind guanidinylated kanamycin A (G Kan A) and guanidinylated neomycin B (G Neo B) were identified via two-dimensional combinatorial screening (2DCS). The results of these studies enabled the "bottom-up" design of a small molecule inhibitor of oncogenic microRNA-10b.

  9. The landscape of fear: The missing link to understand top-down and bottom-up controls of prey abundance?

    Science.gov (United States)

    Identifying factors that may be responsible for affecting and possibly regulating the size of animal populations is a cornerstone in understanding population ecology. The main factors that are thought to influence population size are either resources (bottom-up), predation, (top-down), or interspec...

  10. Bottom-up engineering of biological systems through standard bricks: a modularity study on basic parts and devices.

    Directory of Open Access Journals (Sweden)

    Lorenzo Pasotti

    Full Text Available BACKGROUND: Modularity is a crucial issue in the engineering world, as it enables engineers to achieve predictable outcomes when different components are interconnected. Synthetic Biology aims to apply key concepts of engineering to design and construct new biological systems that exhibit a predictable behaviour. Even if physical and measurement standards have been recently proposed to facilitate the assembly and characterization of biological components, real modularity is still a major research issue. The success of the bottom-up approach strictly depends on the clear definition of the limits in which biological functions can be predictable. RESULTS: The modularity of transcription-based biological components has been investigated in several conditions. First, the activity of a set of promoters was quantified in Escherichia coli via different measurement systems (i.e., different plasmids, reporter genes, ribosome binding sites relative to an in vivo reference promoter. Second, promoter activity variation was measured when two independent gene expression cassettes were assembled in the same system. Third, the interchangeability of input modules (a set of constitutive promoters and two regulated promoters connected to a fixed output device (a logic inverter expressing GFP was evaluated. The three input modules provide tunable transcriptional signals that drive the output device. If modularity persists, identical transcriptional signals trigger identical GFP outputs. To verify this, all the input devices were individually characterized and then the input-output characteristic of the logic inverter was derived in the different configurations. CONCLUSIONS: Promoters activities (referred to a standard promoter can vary when they are measured via different reporter devices (up to 22%, when they are used within a two-expression-cassette system (up to 35% and when they drive another device in a functionally interconnected circuit (up to 44%. This paper

  11. Assessment of Air Pollutants and Greenhouse Gases Emission Over East Asia : A Bottom-up Inventory Perspective

    Science.gov (United States)

    Woo, J. H.; Kim, Y.; Lee, Y. M.; Choi, K. C.; Zhang, Q.; Kurokawa, J. I.; Lee, J. B.; Song, C. K.; Kim, S.

    2014-12-01

    Air pollutants (SLCPs) such as tropospheric ozone and aerosols are mainly affected by meteorological variables and emissions. East Asia is one of important source regions of both anthropogenic and natural air pollutants and GHGs. Therefore, significant environmental changes are expected in the future and air quality modeling is the important methodology to quantitatively evaluate them. Multiple emission inventories with various spatio-temporal resolutions are necessary in support of many different air quality modeling and future climate chage researches. Many emission inventories have been developed for Asia and for Globe, such as TRACE-P, INTEX, REAS, CREATE, MICS-Asia, HTAP, SRES, RCP. Those inventories have been successfully used for many international researches, but also have several limitations including relatively old base year, limited number of pollutants/types, and low transparency of sector/fuel information. Understanding discrepancies and similarities among those intentories would give us a better insights to understand not only present status regional emissions amounts but structures of society and policy that link to the future emissions. To understand these, we; 1) selected several base-year bottom-up anthropogenic emission inventories over East Asia, 2) inter-compare emission inventories with more comprehensive sector/fuel classification, 3) explorer emissions change with more updated acvities, emission factors, and control options. The tentative results show that more than 50% of emission amount could be differ by inventory selection and more than 30% of emissions could be changed by emissions factor and/or control options. More findings regarding to these objectives will be presented on site

  12. Analysis of top-down and bottom-up North American CO2 and CH4 emissions estimates in the second State of the Carbon Cycle Report

    Science.gov (United States)

    Miller, J. B.; Jacobson, A. R.; Bruhwiler, L.; Michalak, A.; Hayes, D. J.; Vargas, R.

    2017-12-01

    In just ten years since publication of the original State of the Carbon Cycle Report in 2007, global CO2 concentrations have risen by more than 22 ppm to 405 ppm. This represents 18% of the increase over preindustrial levels of 280 ppm. This increase is being driven unequivocally by fossil fuel combustion with North American emissions comprising roughly 20% of the global total over the past decade. At the global scale, we know by comparing well-known fossil fuel inventories and rates of atmospheric CO2 increase that about half of all emissions are absorbed at Earth's surface. For North America, however, we can not apply a simple mass balance to determine sources and sinks. Instead, contributions from ecosystems must be estimated using top-down and bottom-up methods. SOCCR-2 estimates North American net CO2 uptake from ecosystems using bottom-up (inventory) methods as 577 +/- 433 TgC/yr and 634 +/- 288 TgC/yr from top-down atmospheric inversions. Although the global terrestrial carbon sink is not precisely known, these values represent possibly 30% of the global values. As with net sink estimates reported in SOCCR, these new top-down and bottom-up estimates are statistically consistent with one another. However, the uncertainties on each of these estimates are now substantially smaller, giving us more confidence about where the truth lies. Atmospheric inversions also yield estimates of interannual variations (IAV) in CO2 and CH4 fluxes. Our syntheses suggest that IAV of ecosystem CO2 fluxes is of order 100 TgC/yr, mainly originating in the conterminous US, with lower variability in boreal and arctic regions. Moreover, this variability is much larger than for inventory-based fluxes reported by the US to the UNFCCC. Unlike CO2, bottom-up CH4 emissions are larger than those derived from large-scale atmospheric data, with the continental discrepancy resulting primarily from differences in arctic and boreal regions. In addition to the current state of the science, we

  13. A Bottom-up Energy Efficiency Improvement Roadmap for China’s Iron and Steel Industry up to 2050

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qi [Northeastern Univ., Shenyang (China); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Arens, Marlene [Fraunhofer Inst. for Systems and Innovation Research (ISI), Karlsruhe (Germany)

    2016-09-01

    Iron and steel manufacturing is energy intensive in China and in the world. China is the world largest steel producer accounting for around half of the world steel production. In this study, we use a bottom-up energy consumption model to analyze four steel-production and energy-efficiency scenarios and evaluate the potential for energy savings from energy-efficient technologies in China’s iron and steel industry between 2010 and 2050. The results show that China’s steel production will rise and peak in the year 2020 at 860 million tons (Mt) per year for the base-case scenario and 680 Mt for the advanced energy-efficiency scenario. From 2020 on, production will gradually decrease to about 510 Mt and 400 Mt in 2050, for the base-case and advanced scenarios, respectively. Energy intensity will decrease from 21.2 gigajoules per ton (G/t) in 2010 to 12.2 GJ/t and 9.9 GJ/t in 2050 for the base-case and advanced scenarios, respectively. In the near term, decreases in iron and steel industry energy intensity will come from adoption of energy-efficient technologies. In the long term, a shift in the production structure of China’s iron and steel industry, reducing the share of blast furnace/basic oxygen furnace production and increasing the share of electric-arc furnace production while reducing the use of pig iron as a feedstock to electric-arc furnaces will continue to reduce the sector’s energy consumption. We discuss barriers to achieving these energy-efficiency gains and make policy recommendations to support improved energy efficiency and a shift in the nature of iron and steel production in China.

  14. How interactions between top-down and bottom-up controls on carbon cycling affect fluxes within and from lakes

    Science.gov (United States)

    Sadro, S.; Piovia-Scott, J.; Nelson, C.; Sickman, J. O.; Knapp, R.

    2017-12-01

    While the role of inland waters in global carbon cycling has grown clearer in recent decades, the extent to which top-down and bottom-up mechanisms interact to regulate dynamics at the catchment scale is not well understood. The degree to which lakes process, export, or store terrestrial carbon is influenced by hydrological variability, variation in the magnitude of terrestrial organic matter (t-OM) entering a system, the efficiency with which such material is metabolized by bacterioplankton, the extent to which it is incorporated into secondary consumer biomass, and by the effects of food-web structure, such as the presence or absence of top predators. However, how these processes interact to mediate carbon fluxes between terrestrial, aquatic, and atmospheric reservoirs remains unclear. We develop a conceptual model that explores how interactions among these factors ultimately affects carbon dynamics using data from lakes located in the Sierra Nevada mountains of California. The Sierra are an excellent system for studies of carbon cycling because elevation-induced landscape gradients in soil development and vegetation cover provide large natural variation in terrestrial inputs to lakes, while variation in confounding factors such as lake morphometry or trophic state is comparatively small. Dissolved organic carbon concentrations increase 100 fold in lakes spanning the alpine to montane elevation gradient found in the Sierra, and fluorescence characteristics reflect an increasingly terrestrial signature with decreasing elevation. Bacterioplankton make up a large proportion of total ecosystem metabolism in these systems, and their metabolic efficiency is tightly coupled to the composition of dissolved organic matter. Stable isotope food web data (δ13C, Δ14C, and δ2H) and measurements of pCO2 from lakes indicate the magnitude of allochthony, rates if carbon cycling, and ecosystem heterotrophy all increase with the increasingly terrestrial signature of dissolved

  15. Regime shift from phytoplankton to macrophyte dominance in a large river: Top-down versus bottom-up effects

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, Carles, E-mail: carles.ibanez@irta.cat [IRTA Aquatic Ecosystems, Carretera Poble Nou, Km 5.5, 43540 St. Carles de la Rapita, Catalonia (Spain); Alcaraz, Carles; Caiola, Nuno; Rovira, Albert; Trobajo, Rosa [IRTA Aquatic Ecosystems, Carretera Poble Nou, Km 5.5, 43540 St. Carles de la Rapita, Catalonia (Spain); Alonso, Miguel [United Research Services S.L., Urgell 143, 08036 Barcelona, Catalonia (Spain); Duran, Concha [Confederacion Hidrografica del Ebro, Sagasta 24-26, 50071 Zaragoza, Aragon (Spain); Jimenez, Pere J. [Grup Natura Freixe, Major 56, 43750 Flix, Catalonia (Spain); Munne, Antoni [Agencia Catalana de l' Aigua, Provenca 204-208, 08036 Barcelona, Catalonia (Spain); Prat, Narcis [Departament d' Ecologia, Universitat de Barcelona, Diagonal 645, 08028 Barcelona Catalonia (Spain)

    2012-02-01

    The lower Ebro River (Catalonia, Spain) has recently undergone a regime shift from a phytoplankton-dominated to a macrophyte-dominated system. This shift is well known in shallow lakes but apparently it has never been documented in rivers. Two initial hypotheses to explain the collapse of the phytoplankton were considered: a) the diminution of nutrients (bottom-up); b) the filtering effect due to the colonization of the zebra mussel (top-down). Data on water quality, hydrology and biological communities (phytoplankton, macrophytes and zebra mussel) was obtained both from existing data sets and new surveys. Results clearly indicate that the decrease in phosphorus is the main cause of a dramatic decrease in chlorophyll and large increase in water transparency, triggering the subsequent colonization of macrophytes in the river bed. A Generalized Linear Model analysis showed that the decrease in dissolved phosphorus had a relative importance 14 times higher than the increase in zebra mussel density to explain the variation of total chlorophyll. We suggest that the described changes in the lower Ebro River can be considered a novel ecosystem shift. This shift is triggering remarkable changes in the biological communities beyond the decrease of phytoplankton and the proliferation of macrophytes, such as massive colonization of Simulidae (black fly) and other changes in the benthic invertebrate communities that are currently investigated. - Highlights: Black-Right-Pointing-Pointer We show a regime shift in a large river from phytoplankton to macrophyte dominance. Black-Right-Pointing-Pointer Two main hypotheses are considered: nutrient decrease and zebra mussel grazing. Black-Right-Pointing-Pointer Phosphorus depletion is found to be the main cause of the phytoplankton decline. Black-Right-Pointing-Pointer We conclude that oligotrophication triggered the colonization of macrophytes. Black-Right-Pointing-Pointer This new regime shift in a river is similar to that described

  16. Regime shift from phytoplankton to macrophyte dominance in a large river: Top-down versus bottom-up effects

    International Nuclear Information System (INIS)

    Ibáñez, Carles; Alcaraz, Carles; Caiola, Nuno; Rovira, Albert; Trobajo, Rosa; Alonso, Miguel; Duran, Concha; Jiménez, Pere J.; Munné, Antoni; Prat, Narcís

    2012-01-01

    The lower Ebro River (Catalonia, Spain) has recently undergone a regime shift from a phytoplankton-dominated to a macrophyte-dominated system. This shift is well known in shallow lakes but apparently it has never been documented in rivers. Two initial hypotheses to explain the collapse of the phytoplankton were considered: a) the diminution of nutrients (bottom-up); b) the filtering effect due to the colonization of the zebra mussel (top-down). Data on water quality, hydrology and biological communities (phytoplankton, macrophytes and zebra mussel) was obtained both from existing data sets and new surveys. Results clearly indicate that the decrease in phosphorus is the main cause of a dramatic decrease in chlorophyll and large increase in water transparency, triggering the subsequent colonization of macrophytes in the river bed. A Generalized Linear Model analysis showed that the decrease in dissolved phosphorus had a relative importance 14 times higher than the increase in zebra mussel density to explain the variation of total chlorophyll. We suggest that the described changes in the lower Ebro River can be considered a novel ecosystem shift. This shift is triggering remarkable changes in the biological communities beyond the decrease of phytoplankton and the proliferation of macrophytes, such as massive colonization of Simulidae (black fly) and other changes in the benthic invertebrate communities that are currently investigated. - Highlights: ► We show a regime shift in a large river from phytoplankton to macrophyte dominance. ► Two main hypotheses are considered: nutrient decrease and zebra mussel grazing. ► Phosphorus depletion is found to be the main cause of the phytoplankton decline. ► We conclude that oligotrophication triggered the colonization of macrophytes. ► This new regime shift in a river is similar to that described in shallow lakes.

  17. Assessing the role of "bottom-up" emissions and simplified chemical mechanisms in reconciling CESM2.0 with TOGA observations from the ORCAS and ATom-2 campaigns

    Science.gov (United States)

    Asher, E.; Emmons, L. K.; Kinnison, D. E.; Tilmes, S.; Hills, A. J.; Hornbrook, R. S.; Stephens, B. B.; Apel, E. C.

    2017-12-01

    Surface albedo and precipitation over the Southern Ocean are sensitive to parameterizations of aerosol formation and cloud dynamics in global climate models. Observations of precursor gases for natural aerosols can help constrain the uncertainty in these parameterizations, if used in conjunction with an appropriately simplified chemical mechanism. We implement current oceanic "bottom-up" emission climatologies of dimethyl sulfide (DMS) and isoprene in CESM2.0 (Lana et al. 2016; Archer et al. 2009) and compare modeled constituents from two separate chemical mechanisms with data obtained from the Trace Organic Gas Analyzer (TOGA) on the O2/N2 Ratios and CO2 Airborne Study in the Southern Ocean (ORCAS) and the Atmospheric Tomography Mission 2 (ATom-2). We use ORCAS measurements of DMS, isoprene, methyl vinyl ketone (MVK) and methacrolein (MACR) from over 10 flights in Jan. - Feb. 2016 as a training dataset to improve "bottom-up" emissions. Thereafter, we evaluate the scaled "top-down" emissions in CESM with TOGA data obtained from the Atmospheric Tomography Mission (ATom-2) in Feb. 2017. Recent laboratory studies at NCAR confirm that TOGA surpasses proton transfer reaction mass spectrometry (PTR-MS) and commercial gas chromatography (GC) instruments with respect to accurate measurements of oxygenated VOCs in low nitrogen oxide (NO) environments, such as MVK and MACR.

  18. Top-Down and Bottom-Up Identification of Proteins by Liquid Extraction Surface Analysis Mass Spectrometry of Healthy and Diseased Human Liver Tissue

    Science.gov (United States)

    Sarsby, Joscelyn; Martin, Nicholas J.; Lalor, Patricia F.; Bunch, Josephine; Cooper, Helen J.

    2014-09-01

    Liquid extraction surface analysis mass spectrometry (LESA MS) has the potential to become a useful tool in the spatially-resolved profiling of proteins in substrates. Here, the approach has been applied to the analysis of thin tissue sections from human liver. The aim was to determine whether LESA MS was a suitable approach for the detection of protein biomarkers of nonalcoholic liver disease (nonalcoholic steatohepatitis, NASH), with a view to the eventual development of LESA MS for imaging NASH pathology. Two approaches were considered. In the first, endogenous proteins were extracted from liver tissue sections by LESA, subjected to automated trypsin digestion, and the resulting peptide mixture was analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) (bottom-up approach). In the second (top-down approach), endogenous proteins were extracted by LESA, and analyzed intact. Selected protein ions were subjected to collision-induced dissociation (CID) and/or electron transfer dissociation (ETD) mass spectrometry. The bottom-up approach resulted in the identification of over 500 proteins; however identification of key protein biomarkers, liver fatty acid binding protein (FABP1), and its variant (Thr→Ala, position 94), was unreliable and irreproducible. Top-down LESA MS analysis of healthy and diseased liver tissue revealed peaks corresponding to multiple (~15-25) proteins. MS/MS of four of these proteins identified them as FABP1, its variant, α-hemoglobin, and 10 kDa heat shock protein. The reliable identification of FABP1 and its variant by top-down LESA MS suggests that the approach may be suitable for imaging NASH pathology in sections from liver biopsies.

  19. Mechatronics by bond graphs an object-oriented approach to modelling and simulation

    CERN Document Server

    Damić, Vjekoslav

    2015-01-01

    This book presents a computer-aided approach to the design of mechatronic systems. Its subject is an integrated modeling and simulation in a visual computer environment. Since the first edition, the simulation software changed enormously, became more user-friendly and easier to use. Therefore, a second edition became necessary taking these improvements into account. The modeling is based on system top-down and bottom-up approach. The mathematical models are generated in a form of differential-algebraic equations and solved using numerical and symbolic algebra methods. The integrated approach developed is applied to mechanical, electrical and control systems, multibody dynamics, and continuous systems. .

  20. Measurements of traffic emissions over a medium-sized city using long-path measurements and comparison against bottom-up city estimates

    Science.gov (United States)

    Waxman, E.; Cossel, K.; Truong, G. W.; Giorgetta, F.; Swann, W.; Coddington, I.; Newbury, N.

    2017-12-01

    Understanding emissions from cities is increasingly important as a growing fraction of the world's population moves to cities. Here we use a novel technology, dual frequency comb spectroscopy, to measure city emissions using a long outdoor open path. We simultaneously measured CO2, CH4, and H2O over the city of Boulder, Colorado and over a clean-air reference path for two months in the fall of 2016. Because of the spatial coverage of our measurements, the layout of the city and power plant locations, and the predominant wind direction, our measurements primarily pick up vehicle emissions. We choose two days with consistent CO2 enhancements over the city relative to the reference path and use a simple 0-D box model to calculate city emissions for these days. We scale these up to annual emissions and compare our measurements with the City of Boulder bottom-up vehicle emissions inventory based on total vehicle miles traveled, fuel efficiency, and vehicle type distribution. We find good agreement (within about a factor of two) between our top-down measurements and the city's bottom-up inventory value.

  1. Bottom-up processing of thermoelectric nanocomposites from colloidal nanocrystal building blocks: the case of Ag{sub 2}Te-PbTe

    Energy Technology Data Exchange (ETDEWEB)

    Cadavid, Doris [Catalonia Institute for Energy Research, IREC (Spain); Ibanez, Maria [Universitat de Barcelona, Departament d' Electronica (Spain); Gorsse, Stephane [Universite de Bordeaux, ICMCB, CNRS (France); Lopez, Antonio M. [Universitat Politecnica de Catalunya, Departament d' Enginyeria Electronica (Spain); Cirera, Albert [Universitat de Barcelona, Departament d' Electronica (Spain); Morante, Joan Ramon; Cabot, Andreu, E-mail: acabot@irec.cat [Catalonia Institute for Energy Research, IREC (Spain)

    2012-12-15

    Nanocomposites are highly promising materials to enhance the efficiency of current thermoelectric devices. A straightforward and at the same time highly versatile and controllable approach to produce nanocomposites is the assembly of solution-processed nanocrystal building blocks. The convenience of this bottom-up approach to produce nanocomposites with homogeneous phase distributions and adjustable composition is demonstrated here by blending Ag{sub 2}Te and PbTe colloidal nanocrystals to form Ag{sub 2}Te-PbTe bulk nanocomposites. The thermoelectric properties of these nanocomposites are analyzed in the temperature range from 300 to 700 K. The evolution of their electrical conductivity and Seebeck coefficient is discussed in terms of the blend composition and the characteristics of the constituent materials.

  2. Top-down and bottom-up influences on demographic rates of Antarctic fur seals Arctocephalus gazella.

    Science.gov (United States)

    Schwarz, Lisa K; Goebel, Michael E; Costa, Daniel P; Kilpatrick, A Marm

    2013-07-01

    Two major drivers in population dynamics are bottom-up processes, such as environmental factors that affect foraging success, and the top-down impacts of predation. Many populations of marine mammal and seabird species appear to be declining in response to reductions in prey associated with the bottom-up effects of climate change. However, predation, which usually occurs at sea and is difficult to observe, may also play a key role. We analysed drivers of population dynamics of Antarctic fur seals Arctocephalus gazella at Cape Shirreff from 1997 to 2009, including a predator that targets pre-weaned pups and bottom-up environmental effects in an ecosystem particularly sensitive to small changes in temperature. We use Bayesian mark-recapture analysis to demonstrate that although large-scale environmental variability affects annual adult survival and reproduction, first year survival appears to be driving the current decline in this population (as defined by a decline in the annual number of pups born). Although the number of pups increased during the first third of the study, first year survival and recruitment of those pups in later years was very low. Such low survival may be driven by leopard seal Hydrurga leptonyx predation, particularly prior to weaning. Our results suggest that without leopard seal predation, this population would most likely increase in size, despite the observed bottom-up effects of climate changes on adult vital rates. More broadly, our results show how age-targeted predation could be a major factor in population decline of K-selected colonial breeders. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

  3. Incentives for Collaborative Governance: Top-Down and Bottom-Up Initiatives in the Swedish Mountain Region

    Directory of Open Access Journals (Sweden)

    Katarina Eckerberg

    2015-08-01

    Full Text Available Governance collaborations between public and private partners are increasingly used to promote sustainable mountain development, yet information is limited on their nature and precise extent. This article analyzes collaboration on environment and natural resource management in Swedish mountain communities to critically assess the kinds of issues these efforts address, how they evolve, who leads them, and what functional patterns they exhibit based on Margerum's (2008 typology of action, organizational, and policy collaboration. Based on official documents, interviews, and the records of 245 collaborative projects, we explore the role of the state, how perceptions of policy failure may inspire collaboration, and the opportunities that European Union funds have created. Bottom-up collaborations, most of which are relatively recent, usually have an action and sometimes an organizational function. Top-down collaborations, however, are usually organizational or policy oriented. Our findings suggest that top-down and bottom-up collaborations are complementary in situations with considerable conflict over time and where public policies have partly failed, such as for nature protection and reindeer grazing. In less contested areas, such as rural development, improving tracks and access, recreation, and fishing, there is more bottom-up, action-oriented collaboration. State support, especially in the form of funding, is central to explaining the emergence of bottom-up action collaboration. Our findings show that the state both initiates and coordinates policy networks and retains a great deal of power over the nature and functioning of collaborative governance. A practical consequence is that there is great overlap—aggravated by sectorized approaches—that creates a heavy workload for some regional partners.

  4. Top-down but not bottom-up visual scanning is affected in hereditary pure cerebellar ataxia.

    Directory of Open Access Journals (Sweden)

    Shunichi Matsuda

    Full Text Available The aim of this study was to clarify the nature of visual processing deficits caused by cerebellar disorders. We studied the performance of two types of visual search (top-down visual scanning and bottom-up visual scanning in 18 patients with pure cerebellar types of spinocerebellar degeneration (SCA6: 11; SCA31: 7. The gaze fixation position was recorded with an eye-tracking device while the subjects performed two visual search tasks in which they looked for a target Landolt figure among distractors. In the serial search task, the target was similar to the distractors and the subject had to search for the target by processing each item with top-down visual scanning. In the pop-out search task, the target and distractor were clearly discernible and the visual salience of the target allowed the subjects to detect it by bottom-up visual scanning. The saliency maps clearly showed that the serial search task required top-down visual attention and the pop-out search task required bottom-up visual attention. In the serial search task, the search time to detect the target was significantly longer in SCA patients than in normal subjects, whereas the search time in the pop-out search task was comparable between the two groups. These findings suggested that SCA patients cannot efficiently scan a target using a top-down attentional process, whereas scanning with a bottom-up attentional process is not affected. In the serial search task, the amplitude of saccades was significantly smaller in SCA patients than in normal subjects. The variability of saccade amplitude (saccadic dysmetria, number of re-fixations, and unstable fixation (nystagmus were larger in SCA patients than in normal subjects, accounting for a substantial proportion of scattered fixations around the items. Saccadic dysmetria, re-fixation, and nystagmus may play important roles in the impaired top-down visual scanning in SCA, hampering precise visual processing of individual items.

  5. Relative Influence of Top-Down ond Bottom-Up Controls on Mixed Severity Burn Patterns in Yosemite National Park, California, USA

    Science.gov (United States)

    Kane, V. R.; Povak, N.; Brooks, M.; Collins, B.; Smith, D.; Churchill, D.

    2015-12-01

    In western North America, recent and projected increases in the frequency and severity of large wildfires have elevated the need to understand the key drivers of fire regimes across landscapes so that managers can predict where fires will have the greatest ecological impact, and anticipate changes under future climate change. Yosemite National Park offers a unique opportunity to study potential biophysical controls on fire severity patterns - fire management in this area has allowed many fires to burn since the 1970s, re-establishing a mixed severity fire regime. Previous studies within the park showed a high level of control from a variety of bottom-up (e.g., fire history, topography) and top-down (e.g., climate) variables on fire severity within a portion of the current study area, and found some evidence controls may break down for the largest fires. In the current study, we sought to identify (1) controls on fire severity across all fires that burned within Yosemite (1984-2013), (2) differences in controls across fire sizes, (3) the contributions of topographic, climatic, and fire history variables to total variance explained, and (4) the influence of spatial autocorrelation on model results. Our study includes 147 fires that burned over 78,500 ha within Yosemite. Modeling results suggested that fire size and shape, topography, and localized climate variables explained fire severity patterns. Fires responded to inter-annual climate variability (top-down) plus local variation in water balance, past fire history, and local topographic variability (bottom-up). Climate-only models lead to the highest level of pure variance explained followed by fire history, and topography models. Climate variables had distinctly non-linear relationships with fire severity, and key drivers were related to winter conditions. Fire severity was positively correlated with fire size, and severity increased towards fire interiors. Steeper and more complex topographies were associated

  6. Assessing Top-Down and Bottom-Up Contributions to Auditory Stream Segregation and Integration With Polyphonic Music

    Directory of Open Access Journals (Sweden)

    Niels R. Disbergen

    2018-03-01

    Full Text Available Polyphonic music listening well exemplifies processes typically involved in daily auditory scene analysis situations, relying on an interactive interplay between bottom-up and top-down processes. Most studies investigating scene analysis have used elementary auditory scenes, however real-world scene analysis is far more complex. In particular, music, contrary to most other natural auditory scenes, can be perceived by either integrating or, under attentive control, segregating sound streams, often carried by different instruments. One of the prominent bottom-up cues contributing to multi-instrument music perception is their timbre difference. In this work, we introduce and validate a novel paradigm designed to investigate, within naturalistic musical auditory scenes, attentive modulation as well as its interaction with bottom-up processes. Two psychophysical experiments are described, employing custom-composed two-voice polyphonic music pieces within a framework implementing a behavioral performance metric to validate listener instructions requiring either integration or segregation of scene elements. In Experiment 1, the listeners' locus of attention was switched between individual instruments or the aggregate (i.e., both instruments together, via a task requiring the detection of temporal modulations (i.e., triplets incorporated within or across instruments. Subjects responded post-stimulus whether triplets were present in the to-be-attended instrument(s. Experiment 2 introduced the bottom-up manipulation by adding a three-level morphing of instrument timbre distance to the attentional framework. The task was designed to be used within neuroimaging paradigms; Experiment 2 was additionally validated behaviorally in the functional Magnetic Resonance Imaging (fMRI environment. Experiment 1 subjects (N = 29, non-musicians completed the task at high levels of accuracy, showing no group differences between any experimental conditions. Nineteen

  7. Assessing Top-Down and Bottom-Up Contributions to Auditory Stream Segregation and Integration With Polyphonic Music.

    Science.gov (United States)

    Disbergen, Niels R; Valente, Giancarlo; Formisano, Elia; Zatorre, Robert J

    2018-01-01

    Polyphonic music listening well exemplifies processes typically involved in daily auditory scene analysis situations, relying on an interactive interplay between bottom-up and top-down processes. Most studies investigating scene analysis have used elementary auditory scenes, however real-world scene analysis is far more complex. In particular, music, contrary to most other natural auditory scenes, can be perceived by either integrating or, under attentive control, segregating sound streams, often carried by different instruments. One of the prominent bottom-up cues contributing to multi-instrument music perception is their timbre difference. In this work, we introduce and validate a novel paradigm designed to investigate, within naturalistic musical auditory scenes, attentive modulation as well as its interaction with bottom-up processes. Two psychophysical experiments are described, employing custom-composed two-voice polyphonic music pieces within a framework implementing a behavioral performance metric to validate listener instructions requiring either integration or segregation of scene elements. In Experiment 1, the listeners' locus of attention was switched between individual instruments or the aggregate (i.e., both instruments together), via a task requiring the detection of temporal modulations (i.e., triplets) incorporated within or across instruments. Subjects responded post-stimulus whether triplets were present in the to-be-attended instrument(s). Experiment 2 introduced the bottom-up manipulation by adding a three-level morphing of instrument timbre distance to the attentional framework. The task was designed to be used within neuroimaging paradigms; Experiment 2 was additionally validated behaviorally in the functional Magnetic Resonance Imaging (fMRI) environment. Experiment 1 subjects ( N = 29, non-musicians) completed the task at high levels of accuracy, showing no group differences between any experimental conditions. Nineteen listeners also

  8. Assessing Top-Down and Bottom-Up Contributions to Auditory Stream Segregation and Integration With Polyphonic Music

    Science.gov (United States)

    Disbergen, Niels R.; Valente, Giancarlo; Formisano, Elia; Zatorre, Robert J.

    2018-01-01

    Polyphonic music listening well exemplifies processes typically involved in daily auditory scene analysis situations, relying on an interactive interplay between bottom-up and top-down processes. Most studies investigating scene analysis have used elementary auditory scenes, however real-world scene analysis is far more complex. In particular, music, contrary to most other natural auditory scenes, can be perceived by either integrating or, under attentive control, segregating sound streams, often carried by different instruments. One of the prominent bottom-up cues contributing to multi-instrument music perception is their timbre difference. In this work, we introduce and validate a novel paradigm designed to investigate, within naturalistic musical auditory scenes, attentive modulation as well as its interaction with bottom-up processes. Two psychophysical experiments are described, employing custom-composed two-voice polyphonic music pieces within a framework implementing a behavioral performance metric to validate listener instructions requiring either integration or segregation of scene elements. In Experiment 1, the listeners' locus of attention was switched between individual instruments or the aggregate (i.e., both instruments together), via a task requiring the detection of temporal modulations (i.e., triplets) incorporated within or across instruments. Subjects responded post-stimulus whether triplets were present in the to-be-attended instrument(s). Experiment 2 introduced the bottom-up manipulation by adding a three-level morphing of instrument timbre distance to the attentional framework. The task was designed to be used within neuroimaging paradigms; Experiment 2 was additionally validated behaviorally in the functional Magnetic Resonance Imaging (fMRI) environment. Experiment 1 subjects (N = 29, non-musicians) completed the task at high levels of accuracy, showing no group differences between any experimental conditions. Nineteen listeners also

  9. Rethinking translational nanomedicine: insights from the 'bottom-up' design of the Porphysome for guiding the clinical development of imageable nanomaterials.

    Science.gov (United States)

    Valic, Michael S; Zheng, Gang

    2016-08-01

    Progress in therapeutics and biotechnologies leveraging new insights in our understanding of cancer biology and progression have had an underwhelming clinical significance thus far. A key challenge arising from the creation of nanomedicines consolidating multiple desirable functionalities into a 'all-in-one' platform is that the layering of functionalities into a single agent introduces novel complexities that significantly impede clinical translation. An alternative design approach seeks to exploit intrinsically multi-functional building block to assemble nanomedicines from the bottom-up, yielding agents with a multiplicity of radiologic, pharmacologic, and therapeutic properties derived from a single constituent. Herein are highlighted recent developments in the formulation, multi-modal imaging, and targeting of an exemplary 'one-for-all' nanomaterial-the Pyropheophorbide Porphysome-treated from a hitherto unexplored clinical design and development perspective. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Chitosan microspheres with an extracellular matrix-mimicking nanofibrous structure as cell-carrier building blocks for bottom-up cartilage tissue engineering

    Science.gov (United States)

    Zhou, Yong; Gao, Huai-Ling; Shen, Li-Li; Pan, Zhao; Mao, Li-Bo; Wu, Tao; He, Jia-Cai; Zou, Duo-Hong; Zhang, Zhi-Yuan; Yu, Shu-Hong

    2015-12-01

    Scaffolds for tissue engineering (TE) which closely mimic the physicochemical properties of the natural extracellular matrix (ECM) have been proven to advantageously favor cell attachment, proliferation, migration and new tissue formation. Recently, as a valuable alternative, a bottom-up TE approach utilizing cell-loaded micrometer-scale modular components as building blocks to reconstruct a new tissue in vitro or in vivo has been proved to demonstrate a number of desirable advantages compared with the traditional bulk scaffold based top-down TE approach. Nevertheless, micro-components with an ECM-mimicking nanofibrous structure are still very scarce and highly desirable. Chitosan (CS), an accessible natural polymer, has demonstrated appealing intrinsic properties and promising application potential for TE, especially the cartilage tissue regeneration. According to this background, we report here the fabrication of chitosan microspheres with an ECM-mimicking nanofibrous structure for the first time based on a physical gelation process. By combining this physical fabrication procedure with microfluidic technology, uniform CS microspheres (CMS) with controlled nanofibrous microstructure and tunable sizes can be facilely obtained. Especially, no potentially toxic or denaturizing chemical crosslinking agent was introduced into the products. Notably, in vitro chondrocyte culture tests revealed that enhanced cell attachment and proliferation were realized, and a macroscopic 3D geometrically shaped cartilage-like composite can be easily constructed with the nanofibrous CMS (NCMS) and chondrocytes, which demonstrate significant application potential of NCMS as the bottom-up cell-carrier components for cartilage tissue engineering.Scaffolds for tissue engineering (TE) which closely mimic the physicochemical properties of the natural extracellular matrix (ECM) have been proven to advantageously favor cell attachment, proliferation, migration and new tissue formation

  11. Top-down vs. bottom-up control on vegetation composition in a tidal marsh depends on scale.

    Directory of Open Access Journals (Sweden)

    Kelly Elschot

    Full Text Available The relative impact of top-down control by herbivores and bottom-up control by environmental conditions on vegetation is a subject of debate in ecology. In this study, we hypothesize that top-down control by goose foraging and bottom-up control by sediment accretion on vegetation composition within an ecosystem can co-occur but operate at different spatial and temporal scales. We used a highly dynamic marsh system with a large population of the Greylag goose (Anser anser to investigate the potential importance of spatial and temporal scales on these processes. At the local scale, Greylag geese grub for below-ground storage organs of the vegetation, thereby creating bare patches of a few square metres within the marsh vegetation. In our study, such activities by Greylag geese allowed them to exert top-down control by setting back vegetation succession. However, we found that the patches reverted back to the initial vegetation type within 12 years. At large spatial (i.e. several square kilometres and temporal scales (i.e. decades, high rates of sediment accretion surpassing the rate of local sea-level rise were found to drive long-term vegetation succession and increased cover of several climax vegetation types. In summary, we conclude that the vegetation composition within this tidal marsh was primarily controlled by the bottom-up factor of sediment accretion, which operates at large spatial as well as temporal scales. Top-down control exerted by herbivores was found to be a secondary process and operated at much smaller spatial and temporal scales.

  12. Top-down controlled and bottom-up triggered orienting of auditory attention to pitch activate overlapping brain networks.

    Science.gov (United States)

    Alho, Kimmo; Salmi, Juha; Koistinen, Sonja; Salonen, Oili; Rinne, Teemu

    2015-11-11

    A number of previous studies have suggested segregated networks of brain areas for top-down controlled and bottom-up triggered orienting of visual attention. However, the corresponding networks involved in auditory attention remain less studied. Our participants attended selectively to a tone stream with either a lower pitch or higher pitch in order to respond to infrequent changes in duration of attended tones. The participants were also required to shift their attention from one stream to the other when guided by a visual arrow cue. In addition to these top-down controlled cued attention shifts, infrequent task-irrelevant louder tones occurred in both streams to trigger attention in a bottom-up manner. Both cued shifts and louder tones were associated with enhanced activity in the superior temporal gyrus and sulcus, temporo-parietal junction, superior parietal lobule, inferior and middle frontal gyri, frontal eye field, supplementary motor area, and anterior cingulate gyrus. Thus, the present findings suggest that in the auditory modality, unlike in vision, top-down controlled and bottom-up triggered attention activate largely the same cortical networks. Comparison of the present results with our previous results from a similar experiment on spatial auditory attention suggests that fronto-parietal networks of attention to location or pitch overlap substantially. However, the auditory areas in the anterior superior temporal cortex might have a more important role in attention to the pitch than location of sounds. This article is part of a Special Issue entitled SI: Prediction and Attention. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Evaluating the Resilience of the Bottom-up Method used to Detect and Benchmark the Smartness of University Campuses

    DEFF Research Database (Denmark)

    Giovannella, Carlo; Andone, Diana; Dascalu, Mihai

    2016-01-01

    A new method to perform a bottom-up extraction and benchmark of the perceived multilevel smartness of complex ecosystems has been recently described and applied to territories and learning ecosystems like university campuses and schools. In this paper we study the resilience of our method...... by comparing and integrating the data collected in several European Campuses during two different academic years, 2014-15 and 2015-16. The overall results are: a) a more adequate and robust definition of the orthogonal multidimensional space of representation of the smartness, and b) the definition...

  14. Bottom-Up Nano-heteroepitaxy of Wafer-Scale Semipolar GaN on (001) Si

    KAUST Repository

    Hus, Jui Wei

    2015-07-15

    Semipolar {101¯1} InGaN quantum wells are grown on (001) Si substrates with an Al-free buffer and wafer-scale uniformity. The novel structure is achieved by a bottom-up nano-heteroepitaxy employing self-organized ZnO nanorods as the strain-relieving layer. This ZnO nanostructure unlocks the problems encountered by the conventional AlN-based buffer, which grows slowly and contaminates the growth chamber. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Smartness of Learning Ecosystems and its Bottom-up Emergence in six European Campuses

    DEFF Research Database (Denmark)

    Giovannella, Carlo; Andone, Diana; Dascalu, Mihai

    2016-01-01

    of the learning process and do not consider the perceptions of the “end users”, i.e. the learners. Recently, as part of the activity promoted by the ASLERD (Association for Smart Learning Ecosystems and Regional Development), we have developed an alternative approach to benchmark learning ecosystems. Such novel...... implementation of such benchmarking approach that involved six European Campuses and more than 700 students. The critical analysis of the outcomes allowed us to identify: a) the set of the most relevant indicators; b) a “smartness” axis in the plan of the first two principal components derived by applying...

  16. Constructing neighborhoods from the bottom up: the case for resident-enerated GIS

    OpenAIRE

    E Talen

    1999-01-01

    As in other areas of planning practice, the use of GIS in neighborhood planning has assumed a technical top-down approach. Given the fact that GIS are essentially about providing and analyzing spatial data, it is difficult to envision how their use in local communities could be construed otherwise. In this paper I make a case for the need to channel intellectual energy into developing an approach and methodology for resident-generated GIS . Specifically I argue that there is a need to exploit...

  17. Experience with a top-down versus bottom-up nuclear engineering educational paradigm

    International Nuclear Information System (INIS)

    Harms, A.A.

    1991-01-01

    Nuclear engineering courses are generally taught from a top-down pedagogical perspective; i.e., one begins with a body of knowledge drawn from advanced nuclear science, engineering, and experience and from this distills a selected part to match the intellectual capacity of the class. This pedagogical approach has evidently been most effect at the graduate level of instruction as evidenced by the ready entry of masters and doctoral students into the professions. A schematic depiction of this approach is suggested and is extended to the undergraduate level of nuclear engineering education

  18. Consensus Emerging from the Bottom-up: the Role of Cognitive Variables in Opinion Dynamics

    Science.gov (United States)

    Giardini, Francesca; Vilone, Daniele; Conte, Rosaria

    2015-09-01

    The study of opinions - e.g., their formation and change, and their effects on our society - by means of theoretical and numerical models has been one of the main goals of sociophysics until now, but it is one of the defining topics addressed by social psychology and complexity science. Despite the flourishing of different models and theories, several key questions still remain unanswered. The aim of this paper is to provide a cognitively grounded computational model of opinions in which they are described as mental representations and defined in terms of distinctive mental features. We also define how these representations change dynamically through different processes, describing the interplay between mental and social dynamics of opinions. We present two versions of the model, one with discrete opinions (voter model-like), and one with continuous ones (Deffuant-like). By means of numerical simulations, we compare the behaviour of our cognitive model with the classical sociophysical models, and we identify interesting differences in the dynamics of consensus for each of the models considered.

  19. Top-down and bottom-up factors in threat-related perception and attention in anxiety.

    Science.gov (United States)

    Sussman, Tamara J; Jin, Jingwen; Mohanty, Aprajita

    2016-12-01

    Anxiety is characterized by the anticipation of aversive future events. The importance of prestimulus anticipatory factors, such as goals and expectations, is well-established in both visual perception and attention. Nevertheless, the prioritized perception of threatening stimuli in anxiety has been attributed to the automatic processing of these stimuli and the role of prestimulus factors has been neglected. The present review will focus on the role of top-down processes that occur before stimulus onset in the perceptual and attentional prioritization of threatening stimuli in anxiety. We will review both the cognitive and neuroscience literature, showing how top-down factors, and interactions between top-down and bottom-up factors may contribute to biased perception of threatening stimuli in normal function and anxiety. The shift in focus from stimulus-driven to endogenous factors and interactions between top-down and bottom-up factors in the prioritization of threat-related stimuli represents an important conceptual advance. In addition, it may yield important clues into the development and maintenance of anxiety, as well as inform novel treatments for anxiety. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Top-down and bottom-up aspects of active search in a real-world environment.

    Science.gov (United States)

    Foulsham, Tom; Chapman, Craig; Nasiopoulos, Eleni; Kingstone, Alan

    2014-03-01

    Visual search has been studied intensively in the labouratory, but lab search often differs from search in the real world in many respects. Here, we used a mobile eye tracker to record the gaze of participants engaged in a realistic, active search task. Participants were asked to walk into a mailroom and locate a target mailbox among many similar mailboxes. This procedure allowed control of bottom-up cues (by making the target mailbox more salient; Experiment 1) and top-down instructions (by informing participants about the cue; Experiment 2). The bottom-up salience of the target had no effect on the overall time taken to search for the target, although the salient target was more likely to be fixated and found once it was within the central visual field. Top-down knowledge of target appearance had a larger effect, reducing the need for multiple head and body movements, and meaning that the target was fixated earlier and from further away. Although there remains much to be discovered in complex real-world search, this study demonstrates that principles from visual search in the labouratory influence gaze in natural behaviour, and provides a bridge between these labouratory studies and research examining vision in natural tasks.

  1. Orchestrated structure evolution: accelerating direct-write nanomanufacturing by combining top-down patterning with bottom-up growth

    Energy Technology Data Exchange (ETDEWEB)

    Kitayaporn, Sathana; Baneyx, Francois; Schwartz, Daniel T [Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1750 (United States); Hoo, Ji Hao; Boehringer, Karl F, E-mail: dts@uw.edu [Department of Electrical Engineering, University of Washington, Seattle, WA 98195-1750 (United States)

    2010-05-14

    Direct-write nanomanufacturing with scanning beams and probes is flexible and can produce high quality products, but it is normally slow and expensive to raster point-by-point over a pattern. We demonstrate the use of an accelerated direct-write nanomanufacturing method called 'orchestrated structure evolution' (OSE), where a direct-write tool patterns a small number of growth 'seeds' that subsequently grow into the final thin film pattern. Through control of seed size and spacing, it is possible to vary the ratio of 'top-down' to 'bottom-up' character of the patterning processes, ranging from conventional top-down raster patterning to nearly pure bottom-up space-filling via seed growth. Electron beam lithography (EBL) and copper electrodeposition were used to demonstrate trade-offs between process time and product quality over nano- to microlength scales. OSE can reduce process times for high-cost EBL patterning by orders of magnitude, at the expense of longer (but inexpensive) copper electrodeposition processing times. We quantify the degradation of pattern quality that accompanies fast OSE patterning by measuring deviations from the desired patterned area and perimeter. We also show that the density of OSE-induced grain boundaries depends upon the seed separation and size. As the seed size is reduced, the uniformity of an OSE film becomes more dependent on details of seed nucleation processes than normally seen for conventionally patterned films.

  2. Novel bottom-up SERS substrates for quantitative and parallelized analytics.

    Science.gov (United States)

    Strelau, Katharina K; Schüler, Thomas; Möller, Robert; Fritzsche, Wolfgang; Popp, Jürgen

    2010-02-01

    Surface-enhanced Raman spectroscopy (SERS) is an emerging technology in the field of analytics. Due to the high sensitivity in connection with specific Raman molecular fingerprint information SERS can be used in a variety of analytical, bioanalytical, and biosensing applications. However, for the SERS effect substrates with metal nanostructures are needed. The broad application of this technology is greatly hampered by the lack of reliable and reproducible substrates. Usually the activity of a given substrate has to be determined by time-consuming experiments such as calibration or ultramicroscopic studies. To use SERS as a standard analytical tool, cheap and reproducible substrates are required, preferably with a characterization technique that does not interfere with the subsequent measurements. Herein we introduce an innovative approach to produce low-cost and large-scale reproducible substrates for SERS applications, which allows easy and economical production of micropatterned SERS active surfaces on a large scale. This approach is based on an enzyme-induced growth of silver nanostructures. The special structural feature of the enzymatically deposited silver nanoparticles prevents the breakdown of SERS activity even at high particle densities (particle density >60%) that lead to a conductive layer. In contrast to other approaches, this substrate exhibits a relationship between electrical conductivity and the resulting SERS activity of a given spot. This enables the prediction of the SERS activity of the nanostructure ensemble and therewith the controllable and reproducible production of SERS substrates of enzymatic silver nanoparticles on a large scale, utilizing a simple measurement of the electrical conductivity. Furthermore, through a correlation between the conductivity and the SERS activity of the substrates it is possible to quantify SERS measurements with these substrates.

  3. Implementing collaborative improvement - top-down, bottom-up or both?

    DEFF Research Database (Denmark)

    Kaltoft, Rasmus; Boer, Harry; Caniato, Federico

    2007-01-01

    The research presented in this article was aimed at increasing the current understanding of the process of developing Collaborative Improvement (CoI) in Extended Manufacturing Enterprises (EME). Based on action research in three EMEs involving a total of 13 companies from five European countries...... with aligning the partners' CoI objectives and an assessment of their collaboration and CoI maturity in order to provide a common platform before actually starting improvement activities. The laissez-faire approach builds on shared goals/vision, meetings on equal terms and joint work, in a non-directive and non...

  4. Smartness of Learning Ecosystems and its bottom-up emergence in six European Campuses

    DEFF Research Database (Denmark)

    Giovannella, Carlo; Andone, Diana; Dascalu, Mihai

    of the learning process and do not consider the perceptions of the “end users”: the learners. Recently, as part of the activity promoted by the Observatory on the Smart City Learning, we have produced an alternative approach to benchmark the learning ecosystems based on the satisfaction of the needs described...... allowed us, among other results, to identify the set of the most relevant indicators out of those that were initially proposed and the identification of a “smartness” axis on the plan of the first two principal components derived from a Principal Component Analysis (PCA) applied to the collected data....

  5. Integration of top-down and bottom-up information for audio organization and retrieval

    DEFF Research Database (Denmark)

    Jensen, Bjørn Sand

    The increasing availability of digital audio and music calls for methods and systems to analyse and organize these digital objects. This thesis investigates three elements related to such systems focusing on the ability to represent and elicit the user's view on the multimedia object and the system...... output. The aim is to provide organization and processing, which aligns with the understanding and needs of the users. Audio and music is often characterized by the large amount of heterogenous information. The rst aspect investigated is the integration of such multi-variate and multi-modal information....... The setup is based on classical regression and choice models placed in the framework of Gaussian processes, which provides flexible non-parametric Bayesian models. The setup consist of a number of likelihood functions suitable for modelling both absolute ratings (direct scaling) and comparative judgements...

  6. Constructing Educational Quality in the Arab Region: A Bottom-Up Critique of Regional Educational Governance

    Science.gov (United States)

    Morgan, Clara

    2017-01-01

    The article challenges the deficit view in which education in the Arab region is portrayed by examining the process of educational regionalisation. It takes as its case study the Arab Regional Agenda for Improving Educational Quality in order to explore the construction of an educational quality space that uses data as a governance model. Drawing…

  7. Bottom-up linking of carbon markets under far-sighted cap coordination and reversibility

    Science.gov (United States)

    Heitzig, Jobst; Kornek, Ulrike

    2018-02-01

    The Paris Agreement relies on nationally determined contributions to reach its targets and asks countries to increase ambitions over time, leaving open the details of this process. Although overcoming countries' myopic `free-riding' incentives requires cooperation, the global public good character of mitigation makes forming coalitions difficult. To cooperate, countries may link their carbon markets1, but is this option beneficial2? Some countries might not participate, not agree to lower caps, or not comply to agreements. While non-compliance might be deterred3, countries can hope that if they don't participate, others might still form a coalition. When considering only one coalition whose members can leave freely, the literature following the publication of refs 4,5 finds meagre prospects for effective collaboration6. Countries also face incentives to increase emissions when linking their markets without a cap agreement7,8. Here, we analyse the dynamics of market linkage using a game-theoretic model of far-sighted coalition formation. In contrast to non-dynamic models and dynamic models without far-sightedness9,10, in our model an efficient global coalition always forms eventually if players are sufficiently far-sighted or caps are coordinated immediately when markets are linked.

  8. Report on developing bottom-up Marginal Abatement Cost Curves (MACCS) for representative farm types

    DEFF Research Database (Denmark)

    Eory, V.; MacLeod, M.; Faverdin, P.

    2015-01-01

    years, discussing the variability in these estimates. The second study reports on marginal abatement cost curves for beef cattle production in Brazil. Finally, the last report presents the conceptual basis of a tool to assess the financial implications of the mitigation measures to be used in parallel...... number of reports done in developed countries show a high variability in the country-level cost-effectiveness estimates, and suggest that approaches providing higher granularity at the spatial and farm type could suit better to the purpose of regional policy development. At the same time, there is still...... a gap in our understanding of economic mitigation potential of agriculture in developing and newly industrialised countries. To address these questions this report presents three studies. The first is a literature review of the cost-effectiveness estimates of mitigation measures published in the past 15...

  9. Forestry and biomass energy projects: bottom-up comparisons of CO2 storage and costs

    International Nuclear Information System (INIS)

    Swisher, J.N.

    1994-01-01

    This paper presents a comprehensive and consistent methodology to account for the costs and net carbon flows of different categories of forestry and biomass energy projects and describes the application of the methodology to several sets of projects in Latin America. The results suggest that both biomass energy development and forestry measures including reforestation and forest protection can contribute significantly to the reduction of global CO 2 emissions, and that local land-use capacity must determine the type of project that is appropriate in specific cases. No single approach alone is sufficient as either a national or global strategy for sustainable land use or carbon emission reduction. The methodology allows consistent comparisons of the costs and quantities of carbon stored in different types of projects and/or national programs, facilitating the inclusion of forestry and biomass energy projects in a possible CO 2 emission reduction regime. (Author)

  10. Bottom-up comparisons of CO2 storage and costs in forestry and biomass energy projects

    International Nuclear Information System (INIS)

    Swisher, J.N.

    1993-01-01

    In order to include forestry and biomass energy projects in a possible CO 2 emission reduction regime, and to compare the costs of individual projects or national programs, it is necessary to determine the rate of equivalency between carbon in fossil fuel emissions and carbon stored in different types of forestry, biomass and renewable energy projects. This paper presents a comprehensive and consistent methodology to account for the costs and carbon flows of different categories of forestry and biomass energy projects and describes the application of the methodology to several sets of projects in Latin America. The results suggest that both biomass energy development and forestry measures including reforestation and forest protection can contribute significantly to the reduction of global CO 2 emissions, and that local land-use capacity must determine the type of project that is appropriate in specific cases. No single approach alone is sufficient as either a national or global strategy for sustainable land use or carbon emission reduction

  11. Carbon balance: the top-down and bottom-up emissions accounting methodologies; Balanco de carbono: a contabilidade das emissoes nas metodologias 'Top-Down' estendida ('Top-Bottom') e 'Bottom-Up'

    Energy Technology Data Exchange (ETDEWEB)

    Alvim, Carlos Feu; Eidelman, Frida; Ferreira, Omar Campos

    2005-08-15

    The Economy and Energy Organization has carried out together with the Ministry of Science and Technology a study on the carbon balance of energy use and transformation. The publication of its results has been made through the e and e periodical in its 48 and 50 issues. In the present issue we are publishing the results corresponding to the extended Top-Down accounting process and those corresponding to the use of the coefficients calculated for the Brazilian inventory from 1990 to 1994, using the Bottom-Up process, to estimate the emissions from 1970 to 2002. By comparing the two results it is possible to evaluate their deficiencies and the possible incoherence in the use of the two methodologies. (author)

  12. Bottom-up risk regulation? How nanotechnology risk knowledge gaps challenge federal and state environmental agencies.

    Science.gov (United States)

    Powell, Maria C; Griffin, Martin P A; Tai, Stephanie

    2008-09-01

    Nanotechnologies have been called the "Next Industrial Revolution." At the same time, scientists are raising concerns about the potential health and environmental risks related to the nano-sized materials used in nanotechnologies. Analyses suggest that current U.S. federal regulatory structures are not likely to adequately address these risks in a proactive manner. Given these trends, the premise of this paper is that state and local-level agencies will likely deal with many "end-of-pipe" issues as nanomaterials enter environmental media without prior toxicity testing, federal standards, or emissions controls. In this paper we (1) briefly describe potential environmental risks and benefits related to emerging nanotechnologies; (2) outline the capacities of the Toxic Substances Control Act, the Clean Air Act, the Clean Water Act, and the Resources Conservation and Recovery Act to address potential nanotechnology risks, and how risk data gaps challenge these regulations; (3) outline some of the key data gaps that challenge state-level regulatory capacities to address nanotechnologies' potential risks, using Wisconsin as a case study; and (4) discuss advantages and disadvantages of state versus federal approaches to nanotechnology risk regulation. In summary, we suggest some ways government agencies can be better prepared to address nanotechnology risk knowledge gaps and risk management.

  13. Growth in NOx emissions from power plants in China: bottom-up estimates and satellite observations

    Directory of Open Access Journals (Sweden)

    Y. Lei

    2012-05-01

    Full Text Available Using OMI (Ozone Monitoring Instrument tropospheric NO2 columns and a nested-grid 3-D global chemical transport model (GEOS-Chem, we investigated the growth in NOx emissions from coal-fired power plants and their contributions to the growth in NO2 columns in 2005–2007 in China. We first developed a unit-based power plant NOx emission inventory for 2005–2007 to support this investigation. The total capacities of coal-fired power generation have increased by 48.8% in 2005–2007, with 92.2% of the total capacity additions coming from generator units with size ≥300 MW. The annual NOx emissions from coal-fired power plants were estimated to be 8.11 Tg NO2 for 2005 and 9.58 Tg NO2 for 2007, respectively. The modeled summer average tropospheric NO2 columns were highly correlated (R2 = 0.79–0.82 with OMI measurements over grids dominated by power plant emissions, with only 7–14% low bias, lending support to the high accuracy of the unit-based power plant NOx emission inventory. The ratios of OMI-derived annual and summer average tropospheric NO2 columns between 2007 and 2005 indicated that most of the grids with significant NO2 increases were related to power plant construction activities. OMI had the capability to trace the changes of NOx emissions from individual large power plants in cases where there is less interference from other NOx sources. Scenario runs from GEOS-Chem model suggested that the new power plants contributed 18.5% and 10% to the annual average NO2 columns in 2007 in Inner Mongolia and North China, respectively. The massive new power plant NOx emissions significantly changed the local NO2 profiles, especially in less polluted areas. A sensitivity study found that changes of NO2 shape factors due to including new power plant emissions increased the summer average OMI tropospheric NO2 columns by 3.8–17.2% for six selected locations, indicating that the updated emission information could help to improve the satellite

  14. Growth in NOx emissions from power plants in China: bottom-up estimates and satellite observations

    Science.gov (United States)

    Wang, S. W.; Zhang, Q.; Streets, D. G.; He, K. B.; Martin, R. V.; Lamsal, L. N.; Chen, D.; Lei, Y.; Lu, Z.

    2012-05-01

    Using OMI (Ozone Monitoring Instrument) tropospheric NO2 columns and a nested-grid 3-D global chemical transport model (GEOS-Chem), we investigated the growth in NOx emissions from coal-fired power plants and their contributions to the growth in NO2 columns in 2005-2007 in China. We first developed a unit-based power plant NOx emission inventory for 2005-2007 to support this investigation. The total capacities of coal-fired power generation have increased by 48.8% in 2005-2007, with 92.2% of the total capacity additions coming from generator units with size ≥300 MW. The annual NOx emissions from coal-fired power plants were estimated to be 8.11 Tg NO2 for 2005 and 9.58 Tg NO2 for 2007, respectively. The modeled summer average tropospheric NO2 columns were highly correlated (R2 = 0.79-0.82) with OMI measurements over grids dominated by power plant emissions, with only 7-14% low bias, lending support to the high accuracy of the unit-based power plant NOx emission inventory. The ratios of OMI-derived annual and summer average tropospheric NO2 columns between 2007 and 2005 indicated that most of the grids with significant NO2 increases were related to power plant construction activities. OMI had the capability to trace the changes of NOx emissions from individual large power plants in cases where there is less interference from other NOx sources. Scenario runs from GEOS-Chem model suggested that the new power plants contributed 18.5% and 10% to the annual average NO2 columns in 2007 in Inner Mongolia and North China, respectively. The massive new power plant NOx emissions significantly changed the local NO2 profiles, especially in less polluted areas. A sensitivity study found that changes of NO2 shape factors due to including new power plant emissions increased the summer average OMI tropospheric NO2 columns by 3.8-17.2% for six selected locations, indicating that the updated emission information could help to improve the satellite retrievals.

  15. Nanoparticle bioconjugates as "bottom-up" assemblies of artifical multienzyme complexes

    Science.gov (United States)

    Keighron, Jacqueline D.

    2010-11-01

    The sequential enzymes of several metabolic pathways have been shown to exist in close proximity with each other in the living cell. Although not proven in all cases, colocalization may have several implications for the rate of metabolite formation. Proximity between the sequential enzymes of a metabolic pathway has been proposed to have several benefits for the overall rate of metabolite formation. These include reduced diffusion distance for intermediates, sequestering of intermediates from competing pathways and the cytoplasm. Restricted diffusion in the vicinity of an enzyme can also cause the pooling of metabolites, which can alter reaction equilibria to control the rate of reaction through inhibition. Associations of metabolic enzymes are difficult to isolate ex vivo due to the weak interactions believed to colocalize sequential enzymes within the cell. Therefore model systems in which the proximity and diffusion of intermediates within the experiment system are controlled are attractive alternatives to explore the effects of colocalization of sequential enzymes. To this end three model systems for multienzyme complexes have been constructed. Direct adsorption enzyme:gold nanoparticle bioconjugates functionalized with malate dehydrogenase (MDH) and citrate synthase (CS) allow for proximity between to the enzymes to be controlled from the nanometer to micron range. Results show that while the enzymes present in the colocalized and non-colocalized systems compared here behaved differently overall the sequential activity of the pathway was improved by (1) decreasing the diffusion distance between active sites, (2) decreasing the diffusion coefficient of the reaction intermediate to prevent escape into the bulk solution, and (3) decreasing the overall amount of bioconjugate in the solution to prevent the pathway from being inhibited by the buildup of metabolite over time. Layer-by-layer (LBL) assemblies of MDH and CS were used to examine the layering effect of

  16. Cold, Hard Justice Lessons from the Fleet: Innovating from the Bottom Up

    Directory of Open Access Journals (Sweden)

    Omar Ha-Redeye

    2017-12-01

    Full Text Available With law school graduates encountering increased difficulty in securing articling positions, legal incubators are an alternative way of providing practical training and mentorship opportunities for young practitioners. Not only do they have the potential to help launch careers in law, but they can also play a major role in increasing access to justice. Though legal incubators have been gaining popularity in law schools across the United States, they are still a novel concept in Canada. This article discusses the resources and practice models used by Fleet Street Law, a law practice in Toronto that evolved into the first legal incubator in Canada. The use of innovative business models allowed for greater service of low income and marginalized populations, especially on a “low-bono” rate, and also assisted in providing essential supports for racialized and minority lawyers early in their career. The flexible and innovative nature of a legal incubator was beneficial for the purposes of experimentation, but there were challenges associated with cost and long-term participation. The model of a practitioner-based incubator, as an alternative to traditional-type clinics, should be strongly considered by law schools to help address some of the market needs in the legal community today.   Dans un contexte dans lequel les diplômés des écoles de droit ont de plus en plus de mal à se trouver une place de stage, les incubateurs juridiques constituent une solution de rechange offrant des possibilités de formation pratique et de mentorat aux jeunes professionnels. En plus d’amorcer leur carrière en droit, ceux-ci peuvent jouer un rôle de premier plan pour accroître l’accès à la justice. Bien que les incubateurs juridiques soient de plus en plus populaires dans les écoles de droit des États-Unis, le concept est encore nouveau au Canada. Cet article traite des ressources et des modèles de pratique qu’utilise le cabinet Fleet Street Law

  17. Self-Assembled Liquid Crystalline Gels Designed from the Bottom Up

    Science.gov (United States)

    Kornfield, Julia

    2005-03-01

    Block copolymers with long side-group liquid-crystalline (LC) midblocks and LC-phobic end-blocks form a physical network that swells readily in a small molecule LC to form model nematic gels with well-defined molecular weight between crosslinks. Ultralong (>800 kg/mol) SGLCP midblocks enable gelation at relatively low concentration (˜5% polymer), which preserves the fast dynamics of small molecule LCs. Similar to LC elastomers, an initially unaligned, polydomain gel aligns under applied strain. Further, the resulting monodomain is so well oriented that it generates clear conoscopic figures. Due to the coupling between nematic order and polymer elasticity, a novel stripe pattern forms when the gels are subjected to electric fields or when the order parameter of the LC solvent changes. Meyer and coworkers have described these patterns using a linear stability analysis that connects the band formation with the spontaneous anisotropy of the SGLCP backbone. Small-angle neutron scattering (SANS) on analogous SGLCP homopolymers confirms that greater chain anisotropy favors band formation and that the sense of anisotropy (prolate or oblate) dictates the initial band orientation. The physical junctions comprised of the LC-phobic endblocks perturb the director field on a nano-scale manifested in a reduction in the mean order parameter of the LC host characterized by both refractive indices (ne, no) and NMR ^2H quadrupole splitting. The physical principles demonstrated for nematic gels allow rational design of gels exhibiting higher-order LC phases, such as ferroelectric gels.

  18. Construction of membrane-bound artificial cells using microfluidics: a new frontier in bottom-up synthetic biology.

    Science.gov (United States)

    Elani, Yuval

    2016-06-15

    The quest to construct artificial cells from the bottom-up using simple building blocks has received much attention over recent decades and is one of the grand challenges in synthetic biology. Cell mimics that are encapsulated by lipid membranes are a particularly powerful class of artificial cells due to their biocompatibility and the ability to reconstitute biological machinery within them. One of the key obstacles in the field centres on the following: how can membrane-based artificial cells be generated in a controlled way and in high-throughput? In particular, how can they be constructed to have precisely defined parameters including size, biomolecular composition and spatial organization? Microfluidic generation strategies have proved instrumental in addressing these questions. This article will outline some of the major principles underpinning membrane-based artificial cells and their construction using microfluidics, and will detail some recent landmarks that have been achieved. © 2016 The Author(s).

  19. The faith of a physicist reflections of a bottom-up thinker : the Gifford lectures for 1993-4

    CERN Document Server

    Polkinghorne, John C

    1994-01-01

    Is it possible to think like a scientist and yet have the faith of a Christian? Although many Westerners might say no, there are also many critically minded individuals who entertain what John Polkinghorne calls a "wistful wariness" toward religion--they feel unable to accept religion on rational grounds yet cannot dismiss it completely. Polkinghorne, both a particle physicist and Anglican priest, here explores just what rational grounds there could be for Christian beliefs, maintaining that the quest for motivated understanding is a concern shared by scientists and religious thinkers alike. Anyone who assumes that religion is based on unquestioning certainties, or that it need not take into account empirical knowledge, will be challenged by Polkinghorne's bottom-up examination of Christian beliefs about events ranging from creation to the resurrection. The author organizes his inquiry around the Nicene Creed, an early statement that continues to summarize Christian beliefs. He applies to each of its tenets ...

  20. Erosion rates as a potential bottom-up control of forest structural characteristics in the Sierra Nevada Mountains.

    Science.gov (United States)

    Milodowski, David T; Mudd, Simon M; Mitchard, Edward T A

    2015-01-01

    The physical characteristics of landscapes place fundamental constraints on vegetation growth and ecosystem function. In actively eroding landscapes, many of these characteristics are controlled by long-term erosion rates: increased erosion rates generate steeper topography and reduce the depth and extent of weathering, limiting moisture storage capacity and impacting nutrient availability. Despite the potentially important bottom-up control that erosion rates place on substrate characteristics, the relationship between the two is largely unexplored. We investigate spatial variations in aboveground biomass (AGB) across a structurally diverse mixed coniferous/deciduous forest with an order of magnitude erosion-rate gradient in the Northern Californian Sierra Nevada, USA, using high resolution LiDAR data and field plots. Mean basin slope, a proxy for erosion rate, accounts for 32% of variance in AGB within our field area (P erosion rate as a potentially important, but hitherto unappreciated, control on AGB and forest structure.

  1. Energetic Bottomup in the Low Countries. Energy transition from the bottom-up. On Happy energetic civilians, Solar and wind cooperatives, New utility companies; Energieke BottomUp in Lage Landen. De Energietransitie van Onderaf. Over Vrolijke energieke burgers, Zon- en windcooperaties, Nieuwe nuts

    Energy Technology Data Exchange (ETDEWEB)

    Schwencke, A.M.

    2012-08-15

    This essay is an outline of the 'energy transition from the bottom-up'. Leading questions are: (1) what are the actual initiatives; (2) who is involved; (3) how does one work (organization, business models); (4) why are people active in this field; (5) what good is it; (6) what is the aim? The essay is based on public information sources (websites, blogs, publications) and interviews with people involved [Dutch] Dit essay is een verkenning van de 'energietransitie van onderaf'. Leidende vragen zijn: (1) om wat voor initiatieven gaat het nu eigenlijk?; (2) wie zijn daarbij betrokken?; (3) hoe gaat men te werk (organisatie, business modellen)?; (4) waarom is men er op die manier mee bezig?; (5) Zet het zoden aan de dijk?; (6) Waar beweegt het naar toe? Het essay baseert zich op openbare bronnen (websites, blogs, publicaties) en gesprekken met mensen uit het veld.

  2. General bottom-up construction of spherical particles by pulsed laser irradiation of colloidal nanoparticles: a case study on CuO.

    Science.gov (United States)

    Wang, Hongqiang; Kawaguchi, Kenji; Pyatenko, Alexander; Li, Xiangyou; Swiatkowska-Warkocka, Zaneta; Katou, Yukiko; Koshizaki, Naoto

    2012-01-02

    The development of a general method to fabricate spherical semiconductor and metal particles advances their promising electrical, optical, magnetic, plasmonic, thermoelectric, and optoelectric applications. Herein, by using CuO as an example, we systematically demonstrate a general bottom-up laser processing technique for the synthesis of submicrometer semiconductor and metal colloidal spheres, in which the unique selective pulsed heating assures the formation of spherical particles. Importantly, we can easily control the size and phase of resultant colloidal spheres by simply tuning the input laser fluence. The heating-melting-fusion mechanism is proposed to be responsible for the size evolution of the spherical particles. We have systematically investigated the influence of experimental parameters, including laser fluence, laser wavelength, laser irradiation time, dispersing liquid, and starting material concentration on the formation of colloidal spheres. We believe that this facile laser irradiation approach represents a major step not only for the fabrication of colloidal spheres but also in the practical application of laser processing for micro- and nanomaterial synthesis. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Perceived Effects of Pornography on the Couple Relationship: Initial Findings of Open-Ended, Participant-Informed, "Bottom-Up" Research.

    Science.gov (United States)

    Kohut, Taylor; Fisher, William A; Campbell, Lorne

    2017-02-01

    The current study adopted a participant-informed, "bottom-up," qualitative approach to identifying perceived effects of pornography on the couple relationship. A large sample (N = 430) of men and women in heterosexual relationships in which pornography was used by at least one partner was recruited through online (e.g., Facebook, Twitter, etc.) and offline (e.g., newspapers, radio, etc.) sources. Participants responded to open-ended questions regarding perceived consequences of pornography use for each couple member and for their relationship in the context of an online survey. In the current sample of respondents, "no negative effects" was the most commonly reported impact of pornography use. Among remaining responses, positive perceived effects of pornography use on couple members and their relationship (e.g., improved sexual communication, more sexual experimentation, enhanced sexual comfort) were reported frequently; negative perceived effects of pornography (e.g., unrealistic expectations, decreased sexual interest in partner, increased insecurity) were also reported, albeit with considerably less frequency. The results of this work suggest new research directions that require more systematic attention.

  4. Combined top-down and bottom-up climate change impact assessment for the hydrological system in the Vu Gia- Thu Bon River Basin.

    Science.gov (United States)

    Tra, Tran Van; Thinh, Nguyen Xuan; Greiving, Stefan

    2018-02-26

    Vu Gia- Thu Bon (VGTB) River Basin, located in the Central Coastal zone of Viet Nam currently faces water shortage. Climate change is expected to exacerbate the challenge. Therefore, there is a need to study the impacts of climate change on water shortage in the river basin. The study adopts a combined top-down and bottom-up climate change impact assessment to address the impacts of climate change on water shortage in the VGTB River Basin. A MIKE BASIN water balance model for the river basin was established to simulate the response of the hydrological system. Simulations were performed through parametrically varying temperature and precipitation to determine the vulnerability space of water shortage. General Circulation Models (GCMs) were then utilized to provide climate projections for the river basin. The output from GCMs was then mapped onto the vulnerability space determined earlier. In total, 9 out of 55 water demand nodes in the simulation are expected to face problematic conditions as future climate changes. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Quantum physics the bottom-up approach : from the simple two-level system to irreducible representations

    CERN Document Server

    Dubbers, Dirk

    2013-01-01

    This concise tutorial provides the bachelor student and the practitioner with a short text on quantum physics that allows them to understand a wealth of quantum phenomena based on a compact, well readable, yet still concise and accurate description of nonrelativistic quantum theory. This “quadrature of the circle” is achieved by concentrating first on the simplest quantum system that still displays all basic features of quantum theory, namely, a system with only two quantized energy levels. For most readers it is very helpful to understand such simple systems before slowly proceeding to more demanding topics like particle entanglement, quantum chaos, or the use of irreducible tensors. This tutorial does not intend to replace the standard textbooks on quantum mechanics, but will help the average student to understand them, often for the first time.

  6. The effect of additive manufacturing on global energy demand : An assessment using a bottom-up approach

    NARCIS (Netherlands)

    Verhoef, L.A.; Budde, Bart; Chockalingam, Cindhuja; García Nodar, Brais; van Wijk, A.J.M.

    2018-01-01

    The effect of disruptive technologies unrelated to the energy sector, such as additive manufacturing (AM), tends to be overlooked in energy scenarios. The present research assessed the potential effect of AM on the global energy demand in four energy scenarios for 2050 with extended versus

  7. A People’s Court? A Bottom-up approach to litigation before the Euopean Court of Justice

    NARCIS (Netherlands)

    Hoevenaars, J.

    2018-01-01

    Each year the European Court of Justice delivers over a thousand decisions on the basis of EU law that affect the Members States as well as the lives of their citizens. Most of these decisions are the result of requests for a preliminary ruling sent by national courts and tribunals seeking an

  8. Development Of A Web Service And Android 'APP' For The Distribution Of Rainfall Data. A Bottom-Up Remote Sensing Data Mining And Redistribution Project In The Age Of The 'Web 2.0'

    Science.gov (United States)

    Mantas, Vasco M.; Pereira, A. J. S. C.; Liu, Zhong

    2013-12-01

    A project was devised to develop a set of freely available applications and web services that can (1) simplify access from Mobile Devices to TOVAS data and (2) support the development of new datasets through data repackaging and mash-up. The bottom-up approach enables the multiplication of new services, often of limited direct interest to the organizations that produces the original, global datasets, but significant to small, local users. Through this multiplication of services, the development cost is transferred to the intermediate or end users and the entire process is made more efficient, even allowing new players to use the data in innovative ways.

  9. Conciliation of top-down and bottom-up methodologies to estimate mobile source emissions in Bogota, Colombia

    Directory of Open Access Journals (Sweden)

    Luis Gabriel Carmona Aparicio

    2016-09-01

    Full Text Available Aim: This study presents the reconciliation of inventories of mobile emission in Bogota in 2013, applying top-down and bottom-up methodologies. Method: It was conducted  a comparison of emissions from different vehicle categories as well as the geographical and temporal distribution of them, by creating a processing code in JAVA. The process employed the largest amount of information available from the authorities of the Capital District, and previous studies. The innovation of this research is the estimation of the traffic flows in secondary roads. It was made from an algorithm that considers road geometry, interaction between arterial and secondary roads, and legal restrictions on traffic. Results: The results show the estimated emissions for pollutants CO, CO2, VOCs, NOx, SO2 and PM, and its comparison with other studies for the city. The values obtained can be classified as minimum and maximum references of the emissions generated in 2013, due to data uncertainty. Conclusions: The project provides an upmost useful tool as input for the authorities in order to identify areas with significant emissions and to develop strategies for emissions reduction, towards improving the air quality of citizens. This method can be replicated in the generation of protocols for estimating emissions from mobile sources but results need to be carefully reviewed given the quality of information sources.

  10. Remediation Performance and Mechanism of Heavy Metals by a Bottom Up Activation and Extraction System Using Multiple Biochemical Materials.

    Science.gov (United States)

    Xiao, Kemeng; Li, Yunzhen; Sun, Yang; Liu, Ruyue; Li, Junjie; Zhao, Yun; Xu, Heng

    2017-09-13

    Soil contamination with heavy metals has caused serious environmental problems and increased the risks to humans and biota. Herein, we developed an effective bottom up metals removal system based on the synergy between the activation of immobilization metal-resistant bacteria and the extraction of bioaccumulator material (Stropharia rugosoannulata). In this system, the advantages of biochar produced at 400 °C and sodium alginate were integrated to immobilize bacteria. Optimized by response surface methodology, the biochar and bacterial suspension were mixed at a ratio of 1:20 (w:v) for 12 h when 2.5% sodium alginate was added to the mixture. Results demonstrated that the system significantly increased the proportion of acid soluble Cd and Cu and improved the soil microecology (microbial counts, soil respiration, and enzyme activities). The maximum extractions of Cd and Cu were 8.79 and 77.92 mg kg -1 , respectively. Moreover, details of the possible mechanistic insight into the metal removal are discussed, which indicate positive correlation with the acetic acid extractable metals and soil microecology. Meanwhile, the "dilution effect" in S. rugosoannulata probably plays an important role in the metal removal process. Furthermore, the metal-resistant bacteria in this system were successfully colonized, and the soil bacteria community were evaluated to understand the microbial diversity in metal-contaminated soil after remediation.

  11. Chemically Engraving Semiconductor Nanowires: Using Three-Dimensional Nanoscale Morphology to Encode Functionality from the Bottom Up.

    Science.gov (United States)

    Christesen, Joseph D; Pinion, Christopher W; Hill, David J; Kim, Seokhyoung; Cahoon, James F

    2016-02-18

    The patterning of semiconductors with nanometer-scale precision is a cornerstone of modern technology. Top-down methods, ranging from photolithography to focused-ion beam milling, are typically used to fabricate complex nanostructures. In this Perspective, we discuss an alternative bottom-up method to encode similar high-resolution morphology in semiconductor nanowires (NWs). This process, termed ENGRAVE for "Encoded Nanowire GRowth and Appearance through VLS and Etching", combines fast modulation of nanowire composition during vapor-liquid-solid (VLS) growth with composition-dependent wet-chemical etching. This method produces cylindrically symmetric structures in which the diameter is modulated on a sub-10 nm axial length scale. The process can produce patterns that range from periodic, centrosymmetric to nonperiodic, asymmetric structures, including gratings, fractals, tapers, ratchets, sinusoids, nanogaps, and nanodots. We discuss the prospect for the ENGRAVE process to become a complementary method of lithographic-like patterning that encodes unique morphologies and physical properties in semiconductors for a range of technologies.

  12. Estimation of Emissions from Sugarcane Field Burning in Thailand Using Bottom-Up Country-Specific Activity Data

    Directory of Open Access Journals (Sweden)

    Wilaiwan Sornpoon

    2014-09-01

    Full Text Available Open burning in sugarcane fields is recognized as a major source of air pollution. However, the assessment of its emission intensity in many regions of the world still lacks information, especially regarding country-specific activity data including biomass fuel load and combustion factor. A site survey was conducted covering 13 sugarcane plantations subject to different farm management practices and climatic conditions. The results showed that pre-harvest and post-harvest burnings are the two main practices followed in Thailand. In 2012, the total production of sugarcane biomass fuel, i.e., dead, dry and fresh leaves, amounted to 10.15 million tonnes, which is equivalent to a fuel density of 0.79 kg∙m−2. The average combustion factor for the pre-harvest and post-harvest burning systems was determined to be 0.64 and 0.83, respectively. Emissions from sugarcane field burning were estimated using the bottom-up country-specific values from the site survey of this study and the results compared with those obtained using default values from the 2006 IPCC Guidelines. The comparison showed that the use of default values lead to underestimating the overall emissions by up to 30% as emissions from post-harvest burning are not accounted for, but it is the second most common practice followed in Thailand.

  13. Enhanced Extraction of Silicon-Vacancy Centers Light Emission Using Bottom-Up Engineered Polycrystalline Diamond Photonic Crystal Slabs.

    Science.gov (United States)

    Ondič, Lukáš; Varga, Marian; Hruška, Karel; Fait, Jan; Kapusta, Peter

    2017-03-28

    Silicon vacancy (SiV) centers are optically active defects in diamond. The SiV centers, in contrast to nitrogen vacancy (NV) centers, possess narrow and efficient luminescence spectrum (centered at ≈738 nm) even at room temperature, which can be utilized for quantum photonics and sensing applications. However, most of light generated in diamond is trapped in the material due to the phenomenon of total internal reflection. In order to overcome this issue, we have prepared two-dimensional photonic crystal slabs from polycrystalline diamond thin layers with high density of SiV centers employing bottom-up growth on quartz templates. We have shown that the spectral overlap between the narrow light emission of the SiV centers and the leaky modes extracting the emission into almost vertical direction (where it can be easily detected) can be obtained by controlling the deposition time. More than 14-fold extraction enhancement of the SiV centers photoluminescence was achieved compared to an uncorrugated sample. Computer simulation confirmed that the extraction enhancement originates from the efficient light-matter interaction between light emitted from the SiV centers and the photonic crystal slab.

  14. Bioenergy decision-making of farms in Northern Finland. Combining the bottom-up and top-down perspectives

    International Nuclear Information System (INIS)

    Snaekin, Juha-Pekka; Muilu, Toivo; Pesola, Tuomo

    2010-01-01

    Finnish farmers' role as energy producers is small compared to their role as energy resource owners. Since climate and energy policy in Finland continues favoring large-scale energy visions, additional investment support for agriculture will stay modest. To utilize fully the energy potential in farms, we analyze the farmers' decision-making environment. First, we present an overview of the Finnish energy policy and economy and their effect on farms (the top-down perspective). Then we analyze the drivers behind the bioenergy decisions of farms in general and in the Oulu region, located in Northern Finland (the bottom-up perspective). There is weak policy coherence between national and regional energy efforts. Strong pressure is placed on farmers to improve their business and marketing knowledge, innovation and financial abilities, education level, and networking skills. In the Oulu region, bioenergy forerunners can be divided in three different groups - investors, entrepreneurs and hobbyists - that have different levels of commitment to their energy businesses. This further stresses the importance of getting quality business services from numerous service providers. (author)

  15. Employment impacts of EU biofuels policy. Combining bottom-up technology information and sectoral market simulations in an input-output framework

    Energy Technology Data Exchange (ETDEWEB)

    Neuwahl, Frederik; Mongelli, Ignazio; Delgado, Luis [European Commission, Joint Research Centre, Institute for Prospective Technological Studies (IPTS), Edificio Expo, c/Inca Garcilaso s/n, 41072 Seville (Spain); Loeschel, Andreas [Centre for European Economic Research (ZEW), L7,1, 68161 Mannheim (Germany)

    2008-12-01

    This paper analyses the employment consequences of policies aimed to support biofuels in the European Union. The promotion of biofuel use has been advocated as a means to promote the sustainable use of natural resources and to reduce greenhouse gas emissions originating from transport activities on the one hand, and to reduce dependence on imported oil and thereby increase security of the European energy supply on the other hand. The employment impacts of increasing biofuels shares are calculated by taking into account a set of elements comprising the demand for capital goods required to produce biofuels, the additional demand for agricultural feedstock, higher fuel prices or reduced household budget in the case of price subsidisation, price effects ensuing from a hypothetical world oil price reduction linked to substitution in the EU market, and price impacts on agro-food commodities. The calculations refer to scenarios for the year 2020 targets as set out by the recent Renewable Energy Roadmap. Employment effects are assessed in an input-output framework taking into account bottom-up technology information to specify biofuels activities and linked to partial equilibrium models for the agricultural and energy sectors. The simulations suggest that biofuels targets on the order of 10-15% could be achieved without adverse net employment effects. (author)

  16. Data-driven approach to dynamic visual attention modelling

    Science.gov (United States)

    Culibrk, Dubravko; Sladojevic, Srdjan; Riche, Nicolas; Mancas, Matei; Crnojevic, Vladimir

    2012-06-01

    Visual attention deployment mechanisms allow the Human Visual System to cope with an overwhelming amount of visual data by dedicating most of the processing power to objects of interest. The ability to automatically detect areas of the visual scene that will be attended to by humans is of interest for a large number of applications, from video coding, video quality assessment to scene understanding. Due to this fact, visual saliency (bottom-up attention) models have generated significant scientific interest in recent years. Most recent work in this area deals with dynamic models of attention that deal with moving stimuli (videos) instead of traditionally used still images. Visual saliency models are usually evaluated against ground-truth eye-tracking data collected from human subjects. However, there are precious few recently published approaches that try to learn saliency from eyetracking data and, to the best of our knowledge, no approaches that try to do so when dynamic saliency is concerned. The paper attempts to fill this gap and describes an approach to data-driven dynamic saliency model learning. A framework is proposed that enables the use of eye-tracking data to train an arbitrary machine learning algorithm, using arbitrary features derived from the scene. We evaluate the methodology using features from a state-of-the art dynamic saliency model and show how simple machine learning algorithms can be trained to distinguish between visually salient and non-salient parts of the scene.

  17. Representing the sublime in the VIMAP and empirical aesthetics: Reviving Edmund Burke's A Philosophical Enquiry into the Origins of Our Ideas of the Sublime and Beautiful. Comment on "Move me, astonish me... delight my eyes and brain: The Vienna Integrated Model of top-down and bottom-up processes in Art Perception (VIMAP) and corresponding affective, evaluative, and neurophysiological correlates" by Matthew Pelowski et al.

    Science.gov (United States)

    Hur, Y.-J.; McManus, I. C.

    2017-07-01

    This commentary considers the role of the sublime in the Vienna Integrated Model of Art Perception (VIMAP; Pelowski, Markey, Forster, Gerger, & Leder [17]), and suggest that it is not precisely conceptualised in the model. In part that reflects different views and usages of the sublime in the literature, and here it is recommended that Burke's [2] view of the sublime is used as a primary framework for empirical research on the sublime.

  18. Independent effects of bottom-up temporal expectancy and top-down spatial attention. An audiovisual study using rhythmic cueing.

    Directory of Open Access Journals (Sweden)

    Alexander eJones

    2015-01-01

    Full Text Available Selective attention to a spatial location has shown enhance perception and facilitate behaviour for events at attended locations. However, selection relies not only on where but also when an event occurs. Recently, interest has turned to how intrinsic neural oscillations in the brain entrain to rhythms in our environment, and, stimuli appearing in or out of synch with a rhythm have shown to modulate perception and performance. Temporal expectations created by rhythms and spatial attention are two processes which have independently shown to affect stimulus processing but it remains largely unknown how, and if, they interact. In four separate tasks, this study investigated the effects of voluntary spatial attention and bottom-up temporal expectations created by rhythms in both unimodal and crossmodal conditions. In each task the participant used an informative cue, either colour or pitch, to direct their covert spatial attention to the left or right, and respond as quickly as possible to a target. The lateralized target (visual or auditory was then presented at the attended or unattended side. Importantly, although not task relevant, the cue was a rhythm of either flashes or beeps. The target was presented in or out of sync (early or late with the rhythmic cue. The results showed participants were faster responding to spatially attended compared to unattended targets in all tasks. Moreover, there was an effect of rhythmic cueing upon response times in both unimodal and crossmodal conditions. Responses were faster to targets presented in sync with the rhythm compared to when they appeared too early in both crossmodal tasks. That is, rhythmic stimuli in one modality influenced the temporal expectancy in the other modality, suggesting temporal expectancies created by rhythms are crossmodal. Interestingly, there was no interaction between top-down spatial attention and rhythmic cueing in any task suggesting these two processes largely influenced

  19. Bottom-up estimation of joint moments during manual lifting using orientation sensors instead of position sensors.

    Science.gov (United States)

    Faber, Gert S; Kingma, Idsart; van Dieën, Jaap H

    2010-05-07

    L5/S1, hip and knee moments during manual lifting tasks are, in a laboratory environment, frequently established by bottom-up inverse dynamics, using force plates to measure ground reaction forces (GRFs) and an optoelectronic system to measure segment positions and orientations. For field measurements, alternative measurement systems are being developed. One alternative is the use of small body-mounted inertial/magnetic sensors (IMSs) and instrumented force shoes to measure segment orientation and GRFs, respectively. However, because IMSs measure segment orientations only, the positions of segments relative to each other and relative to the GRFs have to be determined by linking them, assuming fixed segment lengths and zero joint translation. This will affect the estimated joint positions and joint moments. This study investigated the effect of using segment orientations only (orientation-based method) instead of using orientations and positions (reference method) on three-dimensional joint moments. To compare analysis methods (and not measurement methods), GRFs were measured with a force plate and segment positions and/or orientations were measured using optoelectronic marker clusters for both analysis methods. Eleven male subjects lifted a box from floor level using three lifting techniques: a stoop, a semi-squat and a squat technique. The difference between the two analysis methods remained small for the knee moments: stoop and semi-squat techniques and up to 14% for the squat technique. In conclusion, joint moments during lifting can be estimated with good accuracy at the knee joint and with reasonable accuracy at the hip and L5/S1 joints using segment orientation and GRF data only. Copyright 2010 Elsevier Ltd. All rights reserved.

  20. Bottom-up and top-down processes in body representation: a study of brain-damaged and amputee patients.

    Science.gov (United States)

    Palermo, Liana; Di Vita, Antonella; Piccardi, Laura; Traballesi, Marco; Guariglia, Cecilia

    2014-09-01

    Body representation is a complex process involving different sources of top-down and bottom-up information. Processing the position and the relations among different body parts is necessary to build up a specific body representation, that is, the visuospatial body map (or topological map of the body). Here we aimed to investigate how the loss of peripheral or central information affects this representation by testing amputee and brain-damaged patients. Thirty-two unilateral brain-damaged patients (i.e., left-brain-damaged patients and right-brain-damaged patients who were or were not affected by personal neglect), 18 lower limb amputees and 15 healthy controls took part in the study. The topological body map was assessed by means of the "Frontal body-evocation subtest" (Daurat-Hmeljiak, Stambak, & Berges, 1978), in which participants have to put tiles (each representing a body part) on a small wooden board on which a head is depicted. Group statistical analysis showed that in amputee patients the loss of peripheral information about the right lower limb affects the ability to represent relations among different body parts as much as the loss of top-down information in brain-damaged patients with personal neglect. Single case analysis of brain-damaged patients without personal neglect showed that the topological map of the body was deficient in 1 right-brain-damaged and 2 left-brain-damaged patients. Studying amputee and brain-damaged patients together allowed us to highlight the importance of visuospatial information about one's own limbs and the role of both hemispheres (not only the left one) in creating an efficient topological body representation. (c) 2014 APA, all rights reserved.

  1. Bottom up effects on bacterioplankton growth and composition during summer-autumn transition in the open NW Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    F. Van Wambeke

    2009-04-01

    Full Text Available We examined the vertical and temporal dynamics of nutrients, ectoenzymatic activities under late summer-fall transition period (September–October 2004 in NW Mediterranean Sea in relation to temporal change in factors limiting bacterial production. The depth of the mixed layer (12.8±5.3 m was extremely stable until the onset of the destratification period after 11 October, creating a zone where diffusion of nutrient from the much deeper phosphacline (69±12 m and nitracline (50±8 m was probably strongly limited. However after 1st October, a shallowing of nutriclines occured, particularly marked for nitracline. Hence, the nitrate to phosphate ratio within the mixed layer, although submitted to a high short term variability, shifted the last week of the cruise from 1.1±1.2 to 4.6±3.8, and nitrate increased by a factor 2 (0.092±0.049 μM. A corresponding switch from more than one limitation (PN to P-only limitation of bacterial production was observed during the month as detected by enrichment bioassays. Differences in the identity of the limiting nutrient in surface (5 m: N and P at the beginning, strictly P at the end of the study versus 80 m (labile carbon influence greatly bacterial community structure shift between these two layers. The two communities (5 and 80 m reacted rapidly (24 h to changes in nutrient concentrations by drastic modification of total and active population assemblages resulting in changes in activity. For bacterial production values less than 10 ng C l−1 h−1 (associated to deeper layers, aminopeptidase and lipase exhibited higher activity relative to production whereas phosphatase varied in the same proportions than BP on the range of activities tested. Our results illustrate the effect of bottom-up control on bacterial community structure and activities in the epipelagic NW Mediterranean Sea.

  2. The changing contribution of top-down and bottom-up limitation of mesopredators during 220 years of land use and climate change

    NARCIS (Netherlands)

    Pasanen-Mortensen, Marianne; Elmhagen, Bodil; Lindén, Harto; Bergström, Roger; Wallgren, Märtha; van der Velde, Ype; Cousins, Sara A.O.

    2017-01-01

    Apex predators may buffer bottom-up driven ecosystem change, as top-down suppression may dampen herbivore and mesopredator responses to increased resource availability. However, theory suggests that for this buffering capacity to be realized, the equilibrium abundance of apex predators must

  3. Bottom-up effects on biomass versus top-down effects on identity: a multiple-lake fish community manipulation experiment

    NARCIS (Netherlands)

    Lemmens, P.; Declerck, S.A.J.; Tuytens, K.; Vanderstukken, M.; De Meester, L.

    2018-01-01

    The extent to which ecosystems are regulated by top-down relative to bottom-up control has been a dominant paradigm in ecology for many decades. For lakes, it has been shown that predation by fish is an important determinant of variation in zooplankton and phytoplankton community characteristics.

  4. Bottom-up effects on top-down regulation of a floating aquatic plant by two weevil species: the context-specific nature of biological control

    Science.gov (United States)

    1. Plant nutrition (bottom-up effects) impacts a plant’s ability to sustain herbivory (top-down effects) and affects phytophagous insect fecundity. These factors potentially confound efficacy predictions for biological control projects. We investigated the relative importance of these two forces wi...

  5. Applying bottom-up material flow analysis to identify the system boundaries of non-energy use data in international energy statistics

    NARCIS (Netherlands)

    Weiss, M.|info:eu-repo/dai/nl/156419912; Neelis, M.L.|info:eu-repo/dai/nl/249570173; Zuidberg, M.C.; Patel, M.K.|info:eu-repo/dai/nl/18988097X

    2008-01-01

    Data on the non-energy use of fossil fuels in energy statistics are subject to major uncertainties. We apply a simple bottom-up methodology to recalculate non-energy use for the entire world and for the 50 countries with the highest consumption of fossil fuels for non-energy purposes. We quantify

  6. Identifying Bottom-Up and Top-Down Components of Attentional Weight by Experimental Analysis and Computational Modeling

    Science.gov (United States)

    Nordfang, Maria; Dyrholm, Mads; Bundesen, Claus

    2013-01-01

    The attentional weight of a visual object depends on the contrast of the features of the object to its local surroundings (feature contrast) and the relevance of the features to one's goals (feature relevance). We investigated the dependency in partial report experiments with briefly presented stimuli but unspeeded responses. The task was to…

  7. Bottom up design of nanoparticles for anti-cancer diapeutics: "put the drug in the cancer's food".

    Science.gov (United States)

    Needham, David; Arslanagic, Amina; Glud, Kasper; Hervella, Pablo; Karimi, Leena; Høeilund-Carlsen, Poul-Flemming; Kinoshita, Koji; Mollenhauer, Jan; Parra, Elisa; Utoft, Anders; Walke, Prasad

    2016-11-01

    The story starts in Basel at CLINAM in 2013, when I asked Pieter about making nanoparticles and he advised me to "try this solvent-exchange method we have developed for making limit sized particles". We are particularly interested in what are "limit size materials" because we want to test the feasibility of an idea: could we design, make, develop, and test the concept for treating metastatic cancer by, "Putting the Drug in the Cancer's Food? "Limit size" is the size of the cancer's food, ? the common Low Density Lipoprotein, (LDL) ~20 nm diameter. In this contribution to Pieter's LTAA we focus on the "bottom" (nucleation) and the "up" (growth) of "bottom-up design" as it applies to homogeneous nucleation of especially, hydrophobic drugs and the 8 physico-chemical stages and associated parameters that determine the initial size, and any subsequent coarsening, of a nanoparticle suspension. We show that, when made by the rapid solvent-exchange method, the same sized particles can be obtained without phospholipid. Furthermore, the obtained size follows the predictions of classic nucleation theory when the appropriate values for the parameters (surface tension and supersaturation) at nucleation are included. Calculations on dissolution time for nanoparticles reveal that a typical fewmicromolar-solubility, hydrophobic, anti-cancer drug (like Lapatinib, Niclosamide, Abiraterone, and Fulvestrant) of 500 nm diameter would take between 3?7 s to dissolve in an infinite sink like the blood stream; and a 50 nm particle would dissolve in less than a second! And so the nanoparticle design requires a highly water-insoluble drug, and a tight, encapsulating, impermeable lipid:cholesterol monolayer. While the "Y" junction can be used to mix an ethanolic solution with anti-solvent, we find that a "no-junction" can give equally good results. A series of nanoparticles (DiI-fluorescently labeled Triolein-cored and drug-cored nanoparticles of Orlistat) were then tested in well

  8. Top-down and bottom-up aerosol-cloud closure: towards understanding sources of uncertainty in deriving cloud shortwave radiative flux

    Science.gov (United States)

    Sanchez, Kevin J.; Roberts, Gregory C.; Calmer, Radiance; Nicoll, Keri; Hashimshoni, Eyal; Rosenfeld, Daniel; Ovadnevaite, Jurgita; Preissler, Jana; Ceburnis, Darius; O'Dowd, Colin; Russell, Lynn M.

    2017-08-01

    Top-down and bottom-up aerosol-cloud shortwave radiative flux closures were conducted at the Mace Head Atmospheric Research Station in Galway, Ireland, in August 2015. This study is part of the BACCHUS (Impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding) European collaborative project, with the goal of understanding key processes affecting aerosol-cloud shortwave radiative flux closures to improve future climate predictions and develop sustainable policies for Europe. Instrument platforms include ground-based unmanned aerial vehicles (UAVs)1 and satellite measurements of aerosols, clouds and meteorological variables. The ground-based and airborne measurements of aerosol size distributions and cloud condensation nuclei (CCN) concentration were used to initiate a 1-D microphysical aerosol-cloud parcel model (ACPM). UAVs were equipped for a specific science mission, with an optical particle counter for aerosol distribution profiles, a cloud sensor to measure cloud extinction or a five-hole probe for 3-D wind vectors. UAV cloud measurements are rare and have only become possible in recent years through the miniaturization of instrumentation. These are the first UAV measurements at Mace Head. ACPM simulations are compared to in situ cloud extinction measurements from UAVs to quantify closure in terms of cloud shortwave radiative flux. Two out of seven cases exhibit sub-adiabatic vertical temperature profiles within the cloud, which suggests that entrainment processes affect cloud microphysical properties and lead to an overestimate of simulated cloud shortwave radiative flux. Including an entrainment parameterization and explicitly calculating the entrainment fraction in the ACPM simulations both improved cloud-top radiative closure. Entrainment reduced the difference between simulated and observation-derived cloud-top shortwave radiative flux (δRF) by between 25 and 60 W m-2. After accounting for entrainment

  9. A bottom-up perspective of the net land methanol flux: synthesis of global eddy covariance flux measurements

    Science.gov (United States)

    Wohlfahrt, Georg; Amelynck, Crist; Ammann, Christof; Arneth, Almut; Bamberger, Ines; Goldstein, Allen; Hansel, Armin; Heinesch, Bernhard; Holst, Thomas; Hörtnagl, Lukas; Karl, Thomas; Neftel, Albrecht; McKinney, Karena; Munger, William; Schade, Gunnar; Schoon, Niels

    2014-05-01

    Methanol (CH3OH) is, after methane, the second most abundant VOC in the troposphere and globally represents nearly 20% of the total biospheric VOC emissions. With typical concentrations of 1-10 ppb in the continental boundary layer, methanol plays a crucial role in atmospheric chemistry, which needs to be evaluated in the light of ongoing changes in land use and climate. Previous global methanol budgets have approached the net land flux by summing up the various emission terms (namely primary biogenic and anthropogenic emissions, plant decay and biomass burning) and by subtracting dry and wet deposition, resulting in a net land flux in the range of 75-245 Tg y-1. The data underlying these budget calculations largely stem from small-scale leaf gas exchange measurements and while recently column-integrated remotely sensed methanol concentrations have become available for constraining budget calculations, there have been few attempts to contrast model calculations with direct net ecosystem-scale methanol flux measurements. Here we use eddy covariance methanol flux measurements from 8 sites in Europe and North America to study the magnitude of and controls on the diurnal and seasonal variability in the net ecosystem methanol flux. In correspondence with leaf-level literature, our data show that methanol emission and its strong environmental and biotic control (by temperature and stomatal conductance) prevailed at the more productive (agricultural) sites and at a perturbed forest site. In contrast, at more natural, less productive sites substantial deposition of methanol occurred, in particular during periods of surface wetness. These deposition processes are poorly represented by currently available temperature/light and/or production-driven modelling algorithms. A new framework for modelling the bi-directional land-atmosphere methanol exchange is proposed which accounts for the production of methanol in leaves, the regulation of leaf methanol emission by stomatal

  10. Quantifying the benefit of GOSAT total column CO2 observations for constraining the global carbon budget: An inter-comparison study with bottom-up CO2 flux estimates from MsTMIP (Invited)

    Science.gov (United States)

    Chatterjee, A.; Michalak, A. M.; O'Dell, C.; Huntzinger, D. N.; Kawa, S. R.; Oda, T.; Qiu, X.; Schwalm, C. R.; Yadav, V.

    2013-12-01

    Space-based remote sensing observations, such as those available from the Greenhouse gases Observing SATellite 'IBUKI' (GOSAT) hold great promise for improving the scientific understanding of carbon cycle processes and budgets at regional and global scales. The degree to which the GOSAT CO2 total column (XCO2) observations can constrain global fine-scale fluxes with reasonable precision and accuracy, and the degree to which the dense but lower precision GOSAT data provide additional information relative to the high precision but sparse in situ observations, remain topics of ongoing research. In this study, XCO2 observations retrieved via the GOSAT-ACOS B3.3 algorithm, the Total Column Carbon Observing Network (TCCON) XCO2 retrievals, and CO2 measurements from surface flask sites are assimilated using a geostatistical ensemble square root filter (GEnSRF) to estimate global surface fluxes at high spatial and temporal resolutions (spatial: 1° × 1.25°; temporal: daily). Fluxes are estimated over a period of four consecutive years (June 2008 - May 2012), with only the in situ and TCCON observations constraining the first year surface fluxes, while fluxes for the remaining estimation periods are constrained by all three sets of observations. The estimated fluxes are compared with a suite of bottom-up estimates based on a combination of biospheric fluxes from models participating in the Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) plus anthropogenic flux estimates from the Open-source Data Inventory for Anthropogenic CO2 (ODIAC). Because GEnSRF has been designed to estimate fluxes independently of any a priori flux estimates from flux models and/or inventories, this data assimilation tool allows for a completely independent comparison with the bottom-up estimates. GOSAT observations are found to be particularly valuable for constraining fluxes: (a) during the summer season over the land, and (b) across all seasons over the oceans; in

  11. A Toolkit Modeling Approach for Sustainable Forest Management Planning: Achieving Balance between Science and Local Needs

    Directory of Open Access Journals (Sweden)

    Brian R. Sturtevant

    2007-12-01

    Full Text Available To assist forest managers in balancing an increasing diversity of resource objectives, we developed a toolkit modeling approach for sustainable forest management (SFM. The approach inserts a meta-modeling strategy into a collaborative modeling framework grounded in adaptive management philosophy that facilitates participation among stakeholders, decision makers, and local domain experts in the meta-model building process. The modeling team works iteratively with each of these groups to define essential questions, identify data resources, and then determine whether available tools can be applied or adapted, or whether new tools can be rapidly created to fit the need. The desired goal of the process is a linked series of domain-specific models (tools that balances generalized "top-down" models (i.e., scientific models developed without input from the local system with case-specific customized "bottom-up" models that are driven primarily by local needs. Information flow between models is organized according to vertical (i.e., between scale and horizontal (i.e., within scale dimensions. We illustrate our approach within a 2.1 million hectare forest planning district in central Labrador, a forested landscape where social and ecological values receive a higher priority than economic values. However, the focus of this paper is on the process of how SFM modeling tools and concepts can be rapidly assembled and applied in new locations, balancing efficient transfer of science with adaptation to local needs. We use the Labrador case study to illustrate strengths and challenges uniquely associated with a meta-modeling approach to integrated modeling as it fits within the broader collaborative modeling framework. Principle advantages of the approach include the scientific rigor introduced by peer-reviewed models, combined with the adaptability of meta-modeling. A key challenge is the limited transparency of scientific models to different participatory groups

  12. Café seminars in a bottom-up organizational development project at a Danish radiology department

    DEFF Research Database (Denmark)

    Niss, Karsten Ulrik

    2010-01-01

    Participatory design includes engaging in large-scale information-systems development where participatory design approaches have been applied throughout design and organizational implementation. The keynote suggest to extend the iterative prototyping approach by (1) emphasizing participatory desi...... and development into a sustained and ongoing implementation that constitutes an overall technology-driven organizational change. This sustained participatory design and implementation approach is exemplified through a large-scale project in the Danish healthcare sector...

  13. HEDR modeling approach

    International Nuclear Information System (INIS)

    Shipler, D.B.; Napier, B.A.

    1992-07-01

    This report details the conceptual approaches to be used in calculating radiation doses to individuals throughout the various periods of operations at the Hanford Site. The report considers the major environmental transport pathways--atmospheric, surface water, and ground water--and projects and appropriate modeling technique for each. The modeling sequence chosen for each pathway depends on the available data on doses, the degree of confidence justified by such existing data, and the level of sophistication deemed appropriate for the particular pathway and time period being considered

  14. Modeling prosody: Different approaches

    Science.gov (United States)

    Carmichael, Lesley M.

    2002-11-01

    Prosody pervades all aspects of a speech signal, both in terms of raw acoustic outcomes and linguistically meaningful units, from the phoneme to the discourse unit. It is carried in the suprasegmental features of fundamental frequency, loudness, and duration. Several models have been developed to account for the way prosody organizes speech, and they vary widely in terms of their theoretical assumptions, organizational primitives, actual procedures of application to speech, and intended use (e.g., to generate speech from text vs. to model the prosodic phonology of a language). In many cases, these models overtly contradict one another with regard to their fundamental premises or their identification of the perceptible objects of linguistic prosody. These competing models are directly compared. Each model is applied to the same speech samples. This parallel analysis allows for a critical inspection of each model and its efficacy in assessing the suprasegmental behavior of the speech. The analyses illustrate how different approaches are better equipped to account for different aspects of prosody. Viewing the models and their successes from an objective perspective allows for creative possibilities in terms of combining strengths from models which might otherwise be considered fundamentally incompatible.

  15. Modeling urban building energy use: A review of modeling approaches and procedures

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wenliang; Zhou, Yuyu; Cetin, Kristen; Eom, Jiyong; Wang, Yu; Chen, Gang; Zhang, Xuesong

    2017-12-01

    With rapid urbanization and economic development, the world has been experiencing an unprecedented increase in energy consumption and greenhouse gas (GHG) emissions. While reducing energy consumption and GHG emissions is a common interest shared by major developed and developing countries, actions to enable these global reductions are generally implemented at the city scale. This is because baseline information from individual cities plays an important role in identifying economical options for improving building energy efficiency and reducing GHG emissions. Numerous approaches have been proposed for modeling urban building energy use in the past decades. This paper aims to provide an up-to-date review of the broad categories of energy models for urban buildings and describes the basic workflow of physics-based, bottom-up models and their applications in simulating urban-scale building energy use. Because there are significant differences across models with varied potential for application, strengths and weaknesses of the reviewed models are also presented. This is followed by a discussion of challenging issues associated with model preparation and calibration.

  16. Differences in top-down and bottom-up regulation of macroalgal communities between a reef crest and back reef habitat in Zanzibar

    Science.gov (United States)

    Lilliesköld Sjöö, Gustaf; Mörk, Erik; Andersson, Simon; Melander, Inger

    2011-03-01

    Coral reef ecosystems are subjected to intense pressure from growing coastal populations and subsequently increased nutrient loading and extraction of marine organisms. This development has altered top-down and bottom-up regulation of macroalgae in the reef system. The relative importance of these regulating forces is also influenced by environmental prerequisites, such as exposure to wave action and water motion. Thus, the present study tested the importance of top-down and bottom-up regulation, by manipulation of nutrient availability and grazer abundance, at one reef crest- and one back reef-site in Chwaka bay (Zanzibar, Tanzania). Wave action and water motion may regulate macroalgal communities by affecting the mobility of herbivores and availability of nutrients. The present study was conducted at the onset of the monsoon period, with a general decline of macroalgal cover and biomass in the region; positive effects on biomass development were therefore manifested in reduced decline and not in an actual increase. The experimental study showed that both caging and fertilization had significant impacts on macroalgal community composition but only caging showed any significant effects on biomass development. However, the influences of both these structuring forces were lower at the more exposed crest-site. This period was chosen as most similar studies have been conducted during growth season, often overlooking the studied period. Such previous studies have shown that herbivore exclusion increases macroalgal biomass, while the present study shows that it can also reduce biomass decline during the seasonal die-off by approx 50%. Together, these results suggest an overall larger macroalgal presence on the reef when herbivory is reduced. In general, our results propose that exposure to wave action and water motion functions as an important regulating factor, affecting macroalgal communities by influencing both top-down and bottom-up regulation. In turn, these results

  17. Bottom-Up Enhancement of g-C3N4 Photocatalytic H2 Evolution Utilising Disordering Intermolecular Interactions of Precursor

    Directory of Open Access Journals (Sweden)

    Xue Lu Wang

    2014-01-01

    Full Text Available Disordered intermolecular interaction carbon nitride precursor prepared by water-assisted grinding of dicyandiamide was used for synthesis of g-C3N4. The final sample possesses much looser structure and provides a broadening optical window for effective light harvesting and charge separation efficiency, which exhibits significantly improved H2 evolution by photocatalytic water splitting. The bottom-up mechanochemistry method opens new vistas towards the potential applications of weak interactions in the photocatalysis field and may also stimulate novel ideas completely different from traditional ones for the design and optimization of photocatalysts.

  18. Influence of top-down and bottom-up manipulations on the R-BT065 subcluster of Betaproteobacteria, an abundant group in bacterioplankton of a freshwater reservoir

    Czech Academy of Sciences Publication Activity Database

    Šimek, Karel; Horňák, Karel; Jezbera, Jan; Mašín, Michal; Nedoma, Jiří; Gasol, J. M. .; Schauer, M.

    2005-01-01

    Roč. 71, č. 5 (2005), s. 2381-2390 ISSN 0099-2240 R&D Projects: GA ČR(CZ) GA206/05/0007; GA ČR(CZ) GA206/02/0003 Grant - others:CSIC(ES) DGICYT REN2001-2120/MAR; EU(XE) EVK3-CT-2002-00078; Austrian Science Foundation(AT) P15655 Institutional research plan: CEZ:AV0Z60170517 Keywords : reservoir * top-down and bottom-up control * microbial food webs * bacterivory * bacterial community composition Subject RIV: EE - Microbiology, Virology Impact factor: 3.818, year: 2005

  19. C-STrap Sample Preparation Method--In-Situ Cysteinyl Peptide Capture for Bottom-Up Proteomics Analysis in the STrap Format.

    Directory of Open Access Journals (Sweden)

    Alexandre Zougman

    Full Text Available Recently we introduced the concept of Suspension Trapping (STrap for bottom-up proteomics sample processing that is based upon SDS-mediated protein extraction, swift detergent removal and rapid reactor-type protein digestion in a quartz depth filter trap. As the depth filter surface is made of silica, it is readily modifiable with various functional groups using the silane coupling chemistries. Thus, during the digest, peptides possessing specific features could be targeted for enrichment by the functionalized depth filter material while non-targeted peptides could be collected as an unbound distinct fraction after the digest. In the example presented here the quartz depth filter surface is functionalized with the pyridyldithiol group therefore enabling reversible in-situ capture of the cysteine-containing peptides generated during the STrap-based digest. The described C-STrap method retains all advantages of the original STrap methodology and provides robust foundation for the conception of the targeted in-situ peptide fractionation in the STrap format for bottom-up proteomics. The presented data support the method's use in qualitative and semi-quantitative proteomics experiments.

  20. A Comparative `Bottom Up' Proteomics Strategy for the Site-specific Identification and Quantification of Protein Modifications By Electrophilic Lipids

    OpenAIRE

    Han, Bingnan; Hare, Michael; Wickramasekara, Samanthi; Fang, Yi; Maier, Claudia S.

    2012-01-01

    We report a mass spectrometry-based comparative “bottom up” proteomics approach that combines d0/d4-succinic anhydride labeling with commercially available hydrazine (Hz)-functionalized beads (Affi-gel Hz beads) for detection, identification and relative quantification of site-specific oxylipid modifications in biological matrices. We evaluated and applied this robust and simple method for the quantitative analysis of oxylipid protein conjugates in cardiac mitochondrial proteome samples isola...

  1. A bottom-up method to develop pollution abatement cost curves for coal-fired utility boilers

    Science.gov (United States)

    This paper illustrates a new method to create supply curves for pollution abatement using boiler-level data that explicitly accounts for technology costs and performance. The Coal Utility Environmental Cost (CUECost) model is used to estimate retrofit costs for five different NO...

  2. Preventing violence and reinforcing human security: a rights-based framework for top-down and bottom-up action.

    Science.gov (United States)

    Kjaerulf, Finn; Barahona, Rodrigo

    2010-05-01

    This article explores the violence reduction potential in the intersection between health, criminal justice, and development. It emphasizes public health, rule of law, and equality-driven socioeconomic development as principal concerns in preventing violence. In parts of Latin America, violence has become a serious public health and security problem. Prior studies have explored the risk factors associated with violence as well as experiences in its prevention. These studies and existing approaches to violence prevention provide evidence on where to direct attention and build prevention efforts. This article argues for integrated community-driven and national interventions to create cooperative national- local linkages and embed international human rights law at the national and local levels. Nations struggling with violence should be encouraged to apply an integrated framework to prevent violence and reinforce human security.

  3. A bottom-up method to develop pollution abatement cost curves for coal-fired utility boilers

    International Nuclear Information System (INIS)

    Vijay, Samudra; DeCarolis, Joseph F.; Srivastava, Ravi K.

    2010-01-01

    This paper illustrates a new method to create supply curves for pollution abatement using boiler-level data that explicitly accounts for technology cost and performance. The Coal Utility Environmental Cost (CUECost) model is used to estimate retrofit costs for five different NO x control configurations on a large subset of the existing coal-fired, utility-owned boilers in the US. The resultant data are used to create technology-specific marginal abatement cost curves (MACCs) and also serve as input to an integer linear program, which minimizes system-wide control costs by finding the optimal distribution of NO x controls across the modeled boilers under an emission constraint. The result is a single optimized MACC that accounts for detailed, boiler-specific information related to NO x retrofits. Because the resultant MACCs do not take into account regional differences in air-quality standards or pre-existing NO x controls, the results should not be interpreted as a policy prescription. The general method as well as NO x -specific results presented here should be of significant value to modelers and policy analysts who must estimate the costs of pollution reduction.

  4. A Comparative `Bottom Up' Proteomics Strategy for the Site-specific Identification and Quantification of Protein Modifications By Electrophilic Lipids

    Science.gov (United States)

    Han, Bingnan; Hare, Michael; Wickramasekara, Samanthi; Fang, Yi; Maier, Claudia S.

    2012-01-01

    We report a mass spectrometry-based comparative “bottom up” proteomics approach that combines d0/d4-succinic anhydride labeling with commercially available hydrazine (Hz)-functionalized beads (Affi-gel Hz beads) for detection, identification and relative quantification of site-specific oxylipid modifications in biological matrices. We evaluated and applied this robust and simple method for the quantitative analysis of oxylipid protein conjugates in cardiac mitochondrial proteome samples isolated from 3- and 24-month-old rat hearts. The use of d0/d4-succinic anhydride labeling, Hz-bead based affinity enrichment, nanoLC fractionation and MALDI-ToF/ToF tandem mass spectrometry yielded relative quantification of oxylipid conjugates with residue-specific modification information. Conjugation of acrolein (ACR), 4-hydroxy-2-hexenal (HHE), 4-hydroxy-2-nonenal (HNE) and 4-oxo-2-noneal (ONE) to cysteine, histidine and lysine residues were identified. HHE conjugates were the predominant subset of Michael-type adducts detected in this study. The HHE conjugates showed higher levels in mitochondrial preparations from young heart congruent with previous findings by others that the n-3/n-6 PUFA ratio is higher in young heart mitochondrial membranes. Although this study focuses on protein adducts of reactive oxylipids the method might be equally applicable to protein carbonyl modifications caused by metal catalyzed oxidation reactions. PMID:22842153

  5. Bottom-up design of a gas futures market in East Asia: Lessons from the Dojima rice exchange

    Directory of Open Access Journals (Sweden)

    Xunpeng Shi

    2016-10-01

    Full Text Available The natural gas market in East Asia remains fragmented without a functioning benchmark price to duly reflect the dynamics of demand and supply forces in the region. A functional regional gas futures market, which is highly dependent on the presence of well-developed physical spot trading, is yet to be established. Since the intra-regional pipeline connection is largely non-existent in East Asia, it is the LNG spot cargo trading that is likely to become the basis for the regional gas futures market. This paper offers a novel approach to understanding the development of such a market by analyzing the experience of a different commodity market – the Dojima Rice Exchange (DRE – and identifying potentially transferrable lessons in the market design and the role of government regulations. Based on the case study analysis, implications for the development of natural gas trading hubs in East Asia are offered and an LNG futures exchange design is put forward.

  6. Toward consistency between trends in bottom-up CO2 emissions and top-down atmospheric measurements in the Los Angeles megacity

    Science.gov (United States)

    Newman, Sally; Xu, Xiaomei; Gurney, Kevin R.; Kuang Hsu, Ying; Li, King Fai; Jiang, Xun; Keeling, Ralph; Feng, Sha; O'Keefe, Darragh; Patarasuk, Risa; Weng Wong, Kam; Rao, Preeti; Fischer, Marc L.; Yung, Yuk L.

    2016-03-01

    Large urban emissions of greenhouse gases result in large atmospheric enhancements relative to background that are easily measured. Using CO2 mole fractions and Δ14C and δ13C values of CO2 in the Los Angeles megacity observed in inland Pasadena (2006-2013) and coastal Palos Verdes peninsula (autumn 2009-2013), we have determined time series for CO2 contributions from fossil fuel combustion (Cff) for both sites and broken those down into contributions from petroleum and/or gasoline and natural gas burning for Pasadena. We find a 10 % reduction in Pasadena Cff during the Great Recession of 2008-2010, which is consistent with the bottom-up inventory determined by the California Air Resources Board. The isotopic variations and total atmospheric CO2 from our observations are used to infer seasonality of natural gas and petroleum combustion. The trend of CO2 contributions to the atmosphere from natural gas combustion is out of phase with the seasonal cycle of total natural gas combustion seasonal patterns in bottom-up inventories but is consistent with the seasonality of natural gas usage by the area's electricity generating power plants. For petroleum, the inferred seasonality of CO2 contributions from burning petroleum is delayed by several months relative to usage indicated by statewide gasoline taxes. Using the high-resolution Hestia-LA data product to compare Cff from parts of the basin sampled by winds at different times of year, we find that variations in observed fossil fuel CO2 reflect seasonal variations in wind direction. The seasonality of the local CO2 excess from fossil fuel combustion along the coast, on Palos Verdes peninsula, is higher in autumn and winter than spring and summer, almost completely out of phase with that from Pasadena, also because of the annual variations of winds in the region. Variations in fossil fuel CO2 signals are consistent with sampling the bottom-up Hestia-LA fossil CO2 emissions product for sub-city source regions in the LA

  7. Toward consistency between bottom-up CO2 emissions trends and top-down atmospheric measurements in the Los Angeles megacity

    Science.gov (United States)

    Newman, S.; Xu, X.; Gurney, K. R.; Hsu, Y.-K.; Li, K.-F.; Jiang, X.; Keeling, R.; Feng, S.; O'Keefe, D.; Patarasuk, R.; Wong, K. W.; Rao, P.; Fischer, M. L.; Yung, Y. L.

    2015-10-01

    Large urban emissions of greenhouse gases result in large atmospheric enhancements relative to background that are easily measured. Using CO2 mole fractions and Δ14C and δ13C values of CO2 in the Los Angeles megacity observed in inland Pasadena (2006-2013) and coastal Palos Verdes peninsula (autumn 2009-2013), we have determined time series for CO2 contributions from fossil fuel combustion for both sites and broken those down into contributions from petroleum/gasoline and natural gas burning for Pasadena. We find a 10 % reduction in Pasadena CO2 emissions from fossil fuel combustion during the Great Recession of 2008-2010, which is consistent with the bottom-up inventory determined by the California Air Resources Board. The isotopic variations and total atmospheric CO2 from our observations are used to infer seasonality of natural gas and petroleum combustion. For natural gas, inferred emissions are out of phase with the seasonal cycle of total natural gas combustion seasonal patterns in bottom-up inventories but are consistent with the seasonality of natural gas usage by the area's electricity generating power plants. For petroleum, the inferred seasonality of CO2 emissions from burning petroleum is delayed by several months relative to usage indicated by statewide gasoline taxes. Using the high-resolution Hestia-LA data product to compare emissions from parts of the basin sampled by winds at different times of year, we find that variations in observed fossil fuel CO2 reflect seasonal variations in wind direction. The seasonality of the local CO2 excess from fossil fuel combustion along the coast, on Palos Verdes peninsula, is higher in fall and winter than spring and summer, almost completely out of phase with that from Pasadena, also because of the annual variations of winds in the region. Variations in fossil fuel CO2 signals are consistent with sampling the bottom-up Hestia-LA fossil CO2 emissions product for sub-city source regions in the LA megacity domain

  8. Toward consistency between trends in bottom-up CO2 emissions and top-down atmospheric measurements in the Los Angeles megacity

    Directory of Open Access Journals (Sweden)

    S. Newman

    2016-03-01

    Full Text Available Large urban emissions of greenhouse gases result in large atmospheric enhancements relative to background that are easily measured. Using CO2 mole fractions and Δ14C and δ13C values of CO2 in the Los Angeles megacity observed in inland Pasadena (2006–2013 and coastal Palos Verdes peninsula (autumn 2009–2013, we have determined time series for CO2 contributions from fossil fuel combustion (Cff for both sites and broken those down into contributions from petroleum and/or gasoline and natural gas burning for Pasadena. We find a 10 % reduction in Pasadena Cff during the Great Recession of 2008–2010, which is consistent with the bottom-up inventory determined by the California Air Resources Board. The isotopic variations and total atmospheric CO2 from our observations are used to infer seasonality of natural gas and petroleum combustion. The trend of CO2 contributions to the atmosphere from natural gas combustion is out of phase with the seasonal cycle of total natural gas combustion seasonal patterns in bottom-up inventories but is consistent with the seasonality of natural gas usage by the area's electricity generating power plants. For petroleum, the inferred seasonality of CO2 contributions from burning petroleum is delayed by several months relative to usage indicated by statewide gasoline taxes. Using the high-resolution Hestia-LA data product to compare Cff from parts of the basin sampled by winds at different times of year, we find that variations in observed fossil fuel CO2 reflect seasonal variations in wind direction. The seasonality of the local CO2 excess from fossil fuel combustion along the coast, on Palos Verdes peninsula, is higher in autumn and winter than spring and summer, almost completely out of phase with that from Pasadena, also because of the annual variations of winds in the region. Variations in fossil fuel CO2 signals are consistent with sampling the bottom-up Hestia-LA fossil CO2 emissions product for sub

  9. Bottom-up resource limitation: the ecosystem energy balance predicts the quality of nutrition in a herbivore prey population

    DEFF Research Database (Denmark)

    Fernandez, Nestor; Garcia, Monica; Gil, Esperanza

    2014-01-01

    of the herbivore diet has been insufficiently tested. We hypothesized that in drylands, where water availability is a prime control of ecosystem functioning, remote sensing indicators of vegetation drought stress are critical to predict the nutritional quality of herbivore habitats. This hypothesis was analyzed...... by measuring the dynamics in diet quality for the European rabbit, a key prey in Mediterranean communities. Rabbit nutrition was measured in six habitats throughout a year using faecal nitrogen (FN) content, an indicator of the levels of ingested protein. Then we tested the accuracy for predicting diet quality...... contributed to explain the dynamics of diet quality: models including either TVDI or Hr shower a better fit than those exclusively based in EVI (R2 = 0.43—0.60). Whereas FN showed a positive relationship with EVI, the effect of TVDI and Hr was negative. Extracting the temporal component further allowed us...

  10. Material Modelling - Composite Approach

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    1997-01-01

    This report is part of a research project on "Control of Early Age Cracking" - which, in turn, is part of the major research programme, "High Performance Concrete - The Contractor's Technology (HETEK)", coordinated by the Danish Road Directorate, Copenhagen, Denmark, 1997.A composite-rheological ......This report is part of a research project on "Control of Early Age Cracking" - which, in turn, is part of the major research programme, "High Performance Concrete - The Contractor's Technology (HETEK)", coordinated by the Danish Road Directorate, Copenhagen, Denmark, 1997.A composite......-rheological model of concrete is presented by which consistent predictions of creep, relaxation, and internal stresses can be made from known concrete composition, age at loading, and climatic conditions. No other existing "creep prediction method" offers these possibilities in one approach.The model...... in this report is that cement paste and concrete behave practically as linear-viscoelastic materials from an age of approximately 10 hours. This is a significant age extension relative to earlier studies in the literature where linear-viscoelastic behavior is only demonstrated from ages of a few days. Thus...

  11. Interacting growth and loss rates: The balance of top-down and bottom-up controls in plankton communities

    International Nuclear Information System (INIS)

    Lehman, J.T.

    1991-01-01

    Application of resource-based competition theory to high-nutrient, low-chlorophyll regions of the ocean suggests that single-factor controls on vertical export rates of carbon from euphotic zones are unlikely. High specific rates of grazing or sinking losses interact with growth physiology to produce nutrient requirements in situ that are much higher than those required for the growth of populations held in bottle bioassays. The efficiency of vertical export of carbon by sinking particulates can vary with species composition of the plankton, which in turn can be altered by nutrient manipulation. A simulation model explores possible changes to species composition and vertical carbon flux which might result from addition of Fe to Southern Ocean plankton communities. Nutrient manipulation permits invasion of plankton communities by taxa not originally present and does not necessarily increase the biomass or metabolism of resident species. This makes a priori prediction of fluxes associated with an enriched and altered community fundamentally uncertain if predictions are based on stoichiometries and physiologies of the original resident taxa. Vertical carbon flux could either increase or decrease in response to single-element addition, depending on the attributes of the invading species

  12. Kettlebell swing, snatch, and bottoms-up carry: back and hip muscle activation, motion, and low back loads.

    Science.gov (United States)

    McGill, Stuart M; Marshall, Leigh W

    2012-01-01

    The intent of this study was to quantify spine loading during different kettlebell swings and carries. No previously published studies of tissue loads during kettlebell exercises could be found. Given the popularity of kettlebells, this study was designed to provide an insight into the resulting joint loads. Seven male subjects participated in this investigation. In addition, a single case study of the kettlebell swing was performed on an accomplished kettlebell master. Electromyography, ground reaction forces (GRFs), and 3D kinematic data were recorded during exercises using a 16-kg kettlebell. These variables were input into an anatomically detailed biomechanical model that used normalized muscle activation; GRF; and spine, hip, and knee motion to calculate spine compression and shear loads. It was found that kettlebell swings create a hip-hinge squat pattern characterized by rapid muscle activation-relaxation cycles of substantial magnitudes (∼50% of a maximal voluntary contraction [MVC] for the low back extensors and 80% MVC for the gluteal muscles with a 16-kg kettlebell) resulting in about 3,200 N of low back compression. Abdominal muscular pulses together with the muscle bracing associated with carries create kettlebell-specific training opportunities. Some unique loading patterns discovered during the kettlebell swing included the posterior shear of the L4 vertebra on L5, which is opposite in polarity to a traditional lift. Thus, quantitative analysis provides an insight into why many individuals credit kettlebell swings with restoring and enhancing back health and function, although a few find that they irritate tissues.

  13. Bottom-up, decision support system development : a wetlandsalinity management application in California's San Joaquin Valley

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, Nigel W.T.

    2006-05-10

    Seasonally managed wetlands in the Grasslands Basin ofCalifornia's San Joaquin Valley provide food and shelter for migratorywildfowl during winter months and sport for waterfowl hunters during theannual duck season. Surface water supply to these wetland contain saltwhich, when drained to the San Joaquin River during the annual drawdownperiod, negatively impacts downstream agricultural riparian waterdiverters. Recent environmental regulation, limiting discharges salinityto the San Joaquin River and primarily targeting agricultural non-pointsources, now addresses return flows from seasonally managed wetlands.Real-time water quality management has been advocated as a means ofmatching wetland return flows to the assimilative capacity of the SanJoaquin River. Past attempts to build environmental monitoring anddecision support systems to implement this concept have failed forreasons that are discussed in this paper. These reasons are discussed inthe context of more general challenges facing the successfulimplementation of environmental monitoring, modelling and decisionsupport systems. The paper then provides details of a current researchand development project which will ultimately provide wetland managerswith the means of matching salt exports with the available assimilativecapacity of the San Joaquin River, when fully implemented. Manipulationof the traditional wetland drawdown comes at a potential cost to thesustainability of optimal wetland moist soil plant habitat in thesewetlands - hence the project provides appropriate data and a feedback andresponse mechanism for wetland managers to balance improvements to SanJoaquin River quality with internally-generated information on the healthof the wetland resource. The author concludes the paper by arguing thatthe architecture of the current project decision support system, whencoupled with recent advances in environmental data acquisition, dataprocessing and information dissemination technology, holds

  14. BSRs Elevated by Fluid Upwelling on the Upper Amazon Fan : Bottom-up Controls on Gas Hydrate Stability

    Science.gov (United States)

    Praeg, D.; Silva, C. G.; dos Reis, A. T.; Ketzer, J. M.; Unnithan, V.; Perovano Da Silva, R. J.; Cruz, A. M.; Gorini, C.

    2017-12-01

    stability of gas hydrate occurrences (and gas vents) to the internal dynamics of deep-sea depocentres, in all water depths that structural pathways for fluid migration may form. Gravitational collapse is increasingly recognized to affect passive continental margins, and our findings challenge global models of hydrate inventory over time based solely on in situ methanogenesis.

  15. Thermal conductivity of Li-ion batteries and their electrode configurations - A novel combination of modelling and experimental approach

    Science.gov (United States)

    Werner, Daniel; Loges, André; Becker, Dominic J.; Wetzel, Thomas

    2017-10-01

    A bottom-up approach to calculate the overall and averaged thermal properties of the jelly roll or electrode stack of Li-ion cells in a generally applicable way is introduced. The model is based on temperature-dependent material properties and is specifically applied to a prismatic hardcase cell. The geometrical properties, such as width, depth, height, porosity, tortuosity, and the saturation with electrolyte are considered. Most of the material properties are determined by own measurements within a wide temperature range and compared with literature data. Anisotropic unit cell properties for homogenised three-dimensional thermal models and the corresponding representative thermal conductivity for one- or two-dimensional models can be calculated. A non-destructive measurement technique to determine the thermal conductivity of prismatic hardcase cell geometries and validate the described model is presented.

  16. "Disorganized in time": impact of bottom-up and top-down negative emotion generation on memory formation among healthy and traumatized adolescents.

    Science.gov (United States)

    Guillery-Girard, Bérengère; Clochon, Patrice; Giffard, Bénédicte; Viard, Armelle; Egler, Pierre-Jean; Baleyte, Jean-Marc; Eustache, Francis; Dayan, Jacques

    2013-09-01

    "Travelling in time," a central feature of episodic memory is severely affected among individuals with Post Traumatic Stress Disorder (PTSD) with two opposite effects: vivid traumatic memories are unorganized in temporality (bottom-up processes), non-traumatic personal memories tend to lack spatio-temporal details and false recognitions occur more frequently that in the general population (top-down processes). To test the effect of these two types of processes (i.e. bottom-up and top-down) on emotional memory, we conducted two studies in healthy and traumatized adolescents, a period of life in which vulnerability to emotion is particularly high. Using negative and neutral images selected from the international affective picture system (IAPS), stimuli were divided into perceptual images (emotion generated by perceptual details) and conceptual images (emotion generated by the general meaning of the material). Both categories of stimuli were then used, along with neutral pictures, in a memory task with two phases (encoding and recognition). In both populations, we reported a differential effect of the emotional material on encoding and recognition. Negative perceptual scenes induced an attentional capture effect during encoding and enhanced the recollective distinctiveness. Conversely, the encoding of conceptual scenes was similar to neutral ones, but the conceptual relatedness induced false memories at retrieval. However, among individuals with PTSD, two subgroups of patients were identified. The first subgroup processed the scenes faster than controls, except for the perceptual scenes, and obtained similar performances to controls in the recognition task. The second subgroup group desmonstrated an attentional deficit in the encoding task with no benefit from the distinctiveness associated with negative perceptual scenes on memory performances. These findings provide a new perspective on how negative emotional information may have opposite influences on memory in

  17. 'Epistemology models ontology'− In gesprek met John Polkinghorne ...

    African Journals Online (AJOL)

    The famous premise of John Polkinghorne, 'epistemology models ontology', has been assessed in this article. It is interpreted that its logic is based on a linear trajectory of knowledge → being. Polkinghorne places much emphasis on the fact that he pursues a 'bottom-up' approach, that is, an inductive way of going about ...

  18. Design of the Bottom-up Innovation project--a participatory, primary preventive, organizational level intervention on work-related stress and well-being for workers in Dutch vocational education.

    Science.gov (United States)

    Schelvis, Roosmarijn M C; Oude Hengel, Karen M; Wiezer, Noortje M; Blatter, Birgitte M; van Genabeek, Joost A G M; Bohlmeijer, Ernst T; van der Beek, Allard J

    2013-08-15

    In the educational sector job demands have intensified, while job resources remained the same. A prolonged disbalance between demands and resources contributes to lowered vitality and heightened need for recovery, eventually resulting in burnout, sickness absence and retention problems. Until now stress management interventions in education focused mostly on strengthening the individual capacity to cope with stress, instead of altering the sources of stress at work at the organizational level. These interventions have been only partly effective in influencing burnout and well-being. Therefore, the "Bottom-up Innovation" project tests a two-phased participatory, primary preventive organizational level intervention (i.e. a participatory action approach) that targets and engages all workers in the primary process of schools. It is hypothesized that participating in the project results in increased occupational self-efficacy and organizational efficacy. The central research question: is an organization focused stress management intervention based on participatory action effective in reducing the need for recovery and enhancing vitality in school employees in comparison to business as usual? The study is designed as a controlled trial with mixed methods and three measurement moments: baseline (quantitative measures), six months and 18 months (quantitative and qualitative measures). At first follow-up short term effects of taking part in the needs assessment (phase 1) will be determined. At second follow-up the long term effects of taking part in the needs assessment will be determined as well as the effects of implemented tailored workplace solutions (phase 2). A process evaluation based on quantitative and qualitative data will shed light on whether, how and why the intervention (does not) work(s). "Bottom-up Innovation" is a combined effort of the educational sector, intervention providers and researchers. Results will provide insight into (1) the relation between

  19. Finding regions of interest in pathological images: an attentional model approach

    Science.gov (United States)

    Gómez, Francisco; Villalón, Julio; Gutierrez, Ricardo; Romero, Eduardo

    2009-02-01

    This paper introduces an automated method for finding diagnostic regions-of-interest (RoIs) in histopathological images. This method is based on the cognitive process of visual selective attention that arises during a pathologist's image examination. Specifically, it emulates the first examination phase, which consists in a coarse search for tissue structures at a "low zoom" to separate the image into relevant regions.1 The pathologist's cognitive performance depends on inherent image visual cues - bottom-up information - and on acquired clinical medicine knowledge - top-down mechanisms -. Our pathologist's visual attention model integrates the latter two components. The selected bottom-up information includes local low level features such as intensity, color, orientation and texture information. Top-down information is related to the anatomical and pathological structures known by the expert. A coarse approximation to these structures is achieved by an oversegmentation algorithm, inspired by psychological grouping theories. The algorithm parameters are learned from an expert pathologist's segmentation. Top-down and bottom-up integration is achieved by calculating a unique index for each of the low level characteristics inside the region. Relevancy is estimated as a simple average of these indexes. Finally, a binary decision rule defines whether or not a region is interesting. The method was evaluated on a set of 49 images using a perceptually-weighted evaluation criterion, finding a quality gain of 3dB when comparing to a classical bottom-up model of attention.

  20. Optimization of mass spectrometric parameters improve the identification performance of capillary zone electrophoresis for single-shot bottom-up proteomics analysis.

    Science.gov (United States)

    Zhang, Zhenbin; Dovichi, Norman J

    2018-02-25

    The effects of MS1 injection time, MS2 injection time, dynamic exclusion time, intensity threshold, and isolation width were investigated on the numbers of peptide and protein identifications for single-shot bottom-up proteomics analysis using CZE-MS/MS analysis of a Xenopus laevis tryptic digest. An electrokinetically pumped nanospray interface was used to couple a linear-polyacrylamide coated capillary to a Q Exactive HF mass spectrometer. A sensitive method that used a 1.4 Th isolation width, 60,000 MS2 resolution, 110 ms MS2 injection time, and a top 7 fragmentation produced the largest number of identifications when the CZE loading amount was less than 100 ng. A programmable autogain control method (pAGC) that used a 1.4 Th isolation width, 15,000 MS2 resolution, 110 ms MS2 injection time, and top 10 fragmentation produced the largest number of identifications for CZE loading amounts greater than 100 ng; 7218 unique peptides and 1653 protein groups were identified from 200 ng by using the pAGC method. The effect of mass spectrometer conditions on the performance of UPLC-MS/MS was also investigated. A fast method that used a 1.4 Th isolation width, 30,000 MS2 resolution, 45 ms MS2 injection time, and top 12 fragmentation produced the largest number of identifications for 200 ng UPLC loading amount (6025 unique peptides and 1501 protein groups). This is the first report where the identification number for CZE surpasses that of the UPLC at the 200 ng loading level. However, more peptides (11476) and protein groups (2378) were identified by using UPLC-MS/MS when the sample loading amount was increased to 2 μg with the fast method. To exploit the fast scan speed of the Q-Exactive HF mass spectrometer, higher sample loading amounts are required for single-shot bottom-up proteomics analysis using CZE-MS/MS. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Comparing top-down and bottom-up estimates of methane emissions across multiple U.S. oil and gas basins provides insights into national O&G emissions, mitigation strategies, and research priorities

    Science.gov (United States)

    Lyon, D. R.; Alvarez, R.; Zavala Araiza, D.; Hamburg, S.

    2017-12-01

    We develop a county-level inventory of U.S. anthropogenic methane emissions by integrating multiple data sources including the Drillinginfo oil and gas (O&G) production database, Environmental Protection Agency (EPA) Greenhouse Gas Reporting Program, a previously published gridded EPA Greenhouse Gas Inventory (Maasakkers et al 2016), and recent measurements studies of O&G pneumatic devices, equipment leaks, abandoned wells, and midstream facilities. Our bottom-up estimates of total and O&G methane emissions are consistently lower than top-down, aerial mass balance estimates in ten O&G production areas. We evaluate several hypotheses for the top-down/bottom-up discrepancy including potential bias of the aerial mass balance method, temporal mismatch of top-down and bottom-up emission estimates, and source attribution errors. In most basins, the top-down/bottom-up gap cannot be explained fully without additional O&G emissions from sources not included in traditional inventories, such as super-emitters caused by malfunctions or abnormal process conditions. Top-down/bottom-up differences across multiple basins are analyzed to estimate the magnitude of these additional emissions and constrain total methane emissions from the U.S. O&G supply chain. We discuss the implications for mitigating O&G methane emissions and suggest research priorities for increasing the accuracy of future emission inventories.

  2. Manipulation of the Geometry and Modulation of the Optical Response of Surfactant-Free Gold Nanostars: A Systematic Bottom-Up Synthesis.

    Science.gov (United States)

    De Silva Indrasekara, Agampodi S; Johnson, Sean F; Odion, Ren A; Vo-Dinh, Tuan

    2018-02-28

    Among plasmonic nanoparticles, surfactant-free branched gold nanoparticles have exhibited exceptional properties as a nanoplatform for a wide variety of applications ranging from surface-enhanced Raman scattering sensing and imaging applications to photothermal treatment and photoimmunotherapy for cancer treatments. The effectiveness and reliability of branched gold nanoparticles in biomedical applications strongly rely on the consistency and reproducibility of physical, chemical, optical, and therapeutic properties of nanoparticles, which are mainly governed by their morphological features. Herein, we present an optimized bottom-up synthesis that improves the reproducibility and homogeneity of the gold-branched nanoparticles with desired morphological features and optical properties. We identified that the order of reagent addition is crucial for improved homogeneity of the branched nature of nanoparticles that enable a high batch-to-batch reproducibility and reliability. In addition, a different combination of the synthesis parameters, in particular, additive halides and concentration ratios of reactive Au to Ag and Au to Au seeds, which yield branched nanoparticle of similar localized surface plasmon resonances but with distinguishable changes in the dimensions of the branches, was realized. Overall, our study introduces the design parameters for the purpose-tailored manufacturing of surfactant-free gold nanostars in a reliable manner.

  3. Climate change, pink salmon, and the nexus between bottom-up and top-down forcing in the subarctic Pacific Ocean and Bering Sea.

    Science.gov (United States)

    Springer, Alan M; van Vliet, Gus B

    2014-05-06

    Climate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem.

  4. Dissociated roles of the inferior frontal gyrus and superior temporal sulcus in audiovisual processing: top-down and bottom-up mismatch detection.

    Directory of Open Access Journals (Sweden)

    Takeshi Uno

    Full Text Available Visual inputs can distort auditory perception, and accurate auditory processing requires the ability to detect and ignore visual input that is simultaneous and incongruent with auditory information. However, the neural basis of this auditory selection from audiovisual information is unknown, whereas integration process of audiovisual inputs is intensively researched. Here, we tested the hypothesis that the inferior frontal gyrus (IFG and superior temporal sulcus (STS are involved in top-down and bottom-up processing, respectively, of target auditory information from audiovisual inputs. We recorded high gamma activity (HGA, which is associated with neuronal firing in local brain regions, using electrocorticography while patients with epilepsy judged the syllable spoken by a voice while looking at a voice-congruent or -incongruent lip movement from the speaker. The STS exhibited stronger HGA if the patient was presented with information of large audiovisual incongruence than of small incongruence, especially if the auditory information was correctly identified. On the other hand, the IFG exhibited stronger HGA in trials with small audiovisual incongruence when patients correctly perceived the auditory information than when patients incorrectly perceived the auditory information due to the mismatched visual information. These results indicate that the IFG and STS have dissociated roles in selective auditory processing, and suggest that the neural basis of selective auditory processing changes dynamically in accordance with the degree of incongruity between auditory and visual information.

  5. Dissociated roles of the inferior frontal gyrus and superior temporal sulcus in audiovisual processing: top-down and bottom-up mismatch detection.

    Science.gov (United States)

    Uno, Takeshi; Kawai, Kensuke; Sakai, Katsuyuki; Wakebe, Toshihiro; Ibaraki, Takuya; Kunii, Naoto; Matsuo, Takeshi; Saito, Nobuhito

    2015-01-01

    Visual inputs can distort auditory perception, and accurate auditory processing requires the ability to detect and ignore visual input that is simultaneous and incongruent with auditory information. However, the neural basis of this auditory selection from audiovisual information is unknown, whereas integration process of audiovisual inputs is intensively researched. Here, we tested the hypothesis that the inferior frontal gyrus (IFG) and superior temporal sulcus (STS) are involved in top-down and bottom-up processing, respectively, of target auditory information from audiovisual inputs. We recorded high gamma activity (HGA), which is associated with neuronal firing in local brain regions, using electrocorticography while patients with epilepsy judged the syllable spoken by a voice while looking at a voice-congruent or -incongruent lip movement from the speaker. The STS exhibited stronger HGA if the patient was presented with information of large audiovisual incongruence than of small incongruence, especially if the auditory information was correctly identified. On the other hand, the IFG exhibited stronger HGA in trials with small audiovisual incongruence when patients correctly perceived the auditory information than when patients incorrectly perceived the auditory information due to the mismatched visual information. These results indicate that the IFG and STS have dissociated roles in selective auditory processing, and suggest that the neural basis of selective auditory processing changes dynamically in accordance with the degree of incongruity between auditory and visual information.

  6. Fabricación de electrodos para control de transporte y alineamiento a micro y nanoescalas usando técnicas bottom-up y top-down

    Directory of Open Access Journals (Sweden)

    Darwin Rodríguez

    2014-12-01

    Full Text Available El continuo avance de aplicaciones en dispositivos de autoensamble, posicionamiento, sensores, actuadores, y que permitan controladamente la manipulación de micro y nanoestructuras, han generado amplio interés en el desarrollo de metodologías que permitan optimizar la fabricación de dispositivos para el control y manipulación a micro y nanoescalas. Este proyecto explora técnicas de fabricación de electrodos con el fin de encontrar una técnica óptima y reproducible. Se compara el rendimiento de cada técnica y se describen protocolos de limpieza y seguridad. Se diseñan e implementan tres geometrías para movilizar y posicionar micro y nanopartículas de hierro en una solución de aceite natural. Finalmente se generan campos eléctricos a partir de electroforesis, con el fin de encontrar la curva que describe el desplazamiento de las partículas con respecto al potencial aplicado. Estos resultados generan gran impacto en los actuales esfuerzos de fabricación bottom-up (controlando con campos la ubicación y la movilidad en dispositivos electrónicos. El hecho de fabricar geometría planar con electrodos genera la posibilidad de que se pueda integrar movimiento de partículas a los circuitos integrados que se fabrican en la actualidad.

  7. When top-down becomes bottom up: behaviour of hyperdense howler monkeys (Alouatta seniculus trapped on a 0.6 ha island.

    Directory of Open Access Journals (Sweden)

    Gabriela Orihuela

    Full Text Available Predators are a ubiquitous presence in most natural environments. Opportunities to contrast the behaviour of a species in the presence and absence of predators are thus rare. Here we report on the behaviour of howler monkey groups living under radically different conditions on two land-bridge islands in Lago Guri, Venezuela. One group of 6 adults inhabited a 190-ha island (Danto where they were exposed to multiple potential predators. This group, the control, occupied a home range of 23 ha and contested access to food resources with neighbouring groups in typical fashion. The second group, containing 6 adults, was isolated on a remote, predator-free 0.6 ha islet (Iguana offering limited food resources. Howlers living on the large island moved, fed and rested in a coherent group, frequently engaged in affiliative activities, rarely displayed agonistic behaviour and maintained intergroup spacing through howling. In contrast, the howlers on Iguana showed repulsion, as individuals spent most of their time spaced widely around the perimeter of the island. Iguana howlers rarely engaged in affiliative behaviour, often chased or fought with one another and were not observed to howl. These behaviors are interpreted as adjustments to the unrelenting deprivation associated with bottom-up limitation in a predator-free environment.

  8. Bottom-up-then-up-down Route for Multi-level Construction of Hierarchical Bi2S3 Superstructures with Magnetism Alteration

    Science.gov (United States)

    Wei, Chengzhen; Wang, Lanfang; Dang, Liyun; Chen, Qun; Lu, Qingyi; Gao, Feng

    2015-01-01

    A bottom-up-then-up-down route was proposed to construct multi-level Bi2S3 hierarchical architectures assembled by two-dimensional (2D) Bi2S3 sheet-like networks. BiOCOOH hollow spheres and flower-like structures, which are both assembled by 2D BiOCOOH nanosheets, were prepared first by a “bottom-up” route through a “quasi-emulsion” mechanism. Then the BiOCOOH hierarchical structures were transferred to hierarchical Bi2S3 architectures through an “up-down” route by an ion exchange method. The obtained Bi2S3 nanostructures remain hollow-spherical and flower-like structures of the precursors but the constructing blocks are changed to 2D sheet-like networks interweaving by Bi2S3 nanowires. The close matching of crystal lattices between Bi2S3 and BiOCOOH was believed to be the key reason for the topotactic transformation from BiOCOOH nanosheets to 2D Bi2S3 sheet-like nanowire networks. Magnetism studies reveal that unlike diamagnetism of comparative Bi2S3 nanostructures, the obtained multi-level Bi2S3 structures display S-type hysteresis and ferromagnetism at low field which might result from ordered structure of 2D networks. PMID:26028331

  9. A hybrid modelling approach to develop scenarios for China's carbon dioxide emissions to 2050

    International Nuclear Information System (INIS)

    Gambhir, Ajay; Schulz, Niels; Napp, Tamaryn; Tong, Danlu; Munuera, Luis; Faist, Mark; Riahi, Keywan

    2013-01-01

    This paper describes a hybrid modelling approach to assess the future development of China's energy system, for both a “hypothetical counterfactual baseline” (HCB) scenario and low carbon (“abatement”) scenarios. The approach combines a technology-rich integrated assessment model (MESSAGE) of China's energy system with a set of sector-specific, bottom-up, energy demand models for the transport, buildings and industrial sectors developed by the Grantham Institute for Climate Change at Imperial College London. By exploring technology-specific solutions in all major sectors of the Chinese economy, we find that a combination of measures, underpinned by low-carbon power options based on a mix of renewables, nuclear and carbon capture and storage, would fundamentally transform the Chinese energy system, when combined with increasing electrification of demand-side sectors. Energy efficiency options in these demand sectors are also important. - Highlights: • Combining energy supply and demand models reveals low-carbon technology choices across China's economy. • China could reduce its CO 2 emissions to close to 3 Gt in 2050, costing around 2% of GDP. • Decarbonising the power sector underpins the energy system transformation. • Electrification of industrial processes, building heating and transport is required. • Energy efficiency across the demand side is also important

  10. Different solutions from Finnish and Danish school systems for increasing school-day physical activity and supporting learning: a top down or bottom-up approach

    DEFF Research Database (Denmark)

    Tammelin, Tuija H; Syväoja, Heidi; Bugge, Anna

    2018-01-01

    In Finland, national PA recommendations for school-aged children state that: All 7-to 18-year-olds should be physically active for at least one to two hours daily, continued periods of sitting for more than 2 hours at a time should be avoided, and screen time with entertainment media should...

  11. Linear self-assembly and grafting of gold nanorods into arrayed micrometer-long nanowires on a silicon wafer via a combined top-down/bottom-up approach.

    Science.gov (United States)

    Lestini, Elena; Andrei, Codrin; Zerulla, Dominic

    2018-01-01

    Macroscopically long wire-like arrangements of gold nanoparticles were obtained by controlled evaporation and partial coalescence of an aqueous colloidal solution of capped CTAB-Au nanorods onto a functionalised 3-mercaptopropyl trimethoxysilane (MPTMS) silicon substrate, using a removable, silicon wafer with a hydrophobic surface that serves as a "handrail" for the initial nanorods' linear self-assembly. The wire-like structures display a quasi-continuous pattern by thermal annealing of the gold nanorods when the solvent (i.e. water) is evaporated at temperatures rising from 20°C to 140°C. Formation of both single and self-replicating parallel 1D-superstructures consisting of two or even three wires is observed and explained under such conditions.

  12. Top-down and bottom-up approaches to greenhouse gas inventory methods—a comparison between national- and forest-scale reporting methods

    Science.gov (United States)

    David Nicholls; Frank Barnes; Felicia Acrea; Chinling Chen; Lara Y. Buluç; Michele M. Parker

    2015-01-01

    Federal agencies are mandated to measure, manage, and reduce greenhouse gas (GHG) emissions. The General Services Administration (GSA) Carbon Footprint Tool (CFT) is an online tool built to utilize measured GHG inventories to help Forest Service units streamline reporting and make informed decisions about operational efficiency. In fiscal year 2013, the Forest Service...

  13. A proposed eye irritation testing strategy to reduce and replace in vivo studies using Bottom-Up and Top-Down approaches

    NARCIS (Netherlands)

    Scott, L.; Eskes, C.; Hoffmann, S.; Adriaens, E.; Alepée, N.; Bufo, M.; Clothier, R.; Facchini, D.; Faller, C.; Guest, R.; Harbell, J.; Hartung, T.; Kamp, H.; Varlet, B.L.; Meloni, M.; McNamee, P.; Osborne, R.; Pape, W.; Pfannenbecker, U.; Prinsen, M.; Seaman, C.; Spielmann, H.; Stokes, W.; Trouba, K.; Berghe, C.V.d.; Goethem, F.V.; Vassallo, M.; Vinardell, P.; Zuang, V.

    2010-01-01

    In spite of over 20 years of effort, no single in vitro assay has been developed and validated as a full regulatory replacement for the Draize Eye Irritation test. However, companies have been using in vitro methods to screen new formulations and in some cases as their primary assessment of eye

  14. A Multilateral Strategy for Rural Somalia: Providing a Foundation for the Social and Economic Reconstruction of Somalia Using a Bottom up Approach

    Science.gov (United States)

    2009-06-12

    extremists, warlords, terrorists , and insurgents. This is the biggest challenge for the African Mission in Somalia (AMISOM), United Nation...LAIKIPIA West Laikipia Rain Water Harvesting Project Settled Agricultural Community - Dry land Farming Technology -Rain catchment tanks

  15. On the choice of the demand and hydraulic modeling approach to WDN real-time simulation

    Science.gov (United States)

    Creaco, Enrico; Pezzinga, Giuseppe; Savic, Dragan

    2017-07-01

    This paper aims to analyze two demand modeling approaches, i.e., top-down deterministic (TDA) and bottom-up stochastic (BUA), with particular reference to their impact on the hydraulic modeling of water distribution networks (WDNs). In the applications, the hydraulic modeling is carried out through the extended period simulation (EPS) and unsteady flow modeling (UFM). Taking as benchmark the modeling conditions that are closest to the WDN's real operation (UFM + BUA), the analysis showed that the traditional use of EPS + TDA produces large pressure head and water discharge errors, which can be attenuated only when large temporal steps (up to 1 h in the case study) are used inside EPS. The use of EPS + BUA always yields better results. Indeed, EPS + BUA already gives a good approximation of the WDN's real operation when intermediate temporal steps (larger than 2 min in the case study) are used for the simulation. The trade-off between consistency of results and computational burden makes EPS + BUA the most suitable tool for real-time WDN simulation, while benefitting from data acquired through smart meters for the parameterization of demand generation models.

  16. Enhancing the Wettability of High Aspect-Ratio Through-Silicon Vias Lined with LPCVD Silicon Nitride or PE-ALD Titanium Nitride for Void-Free Bottom-Up Copper Electroplating

    NARCIS (Netherlands)

    Saadaoui, M.; van Zeijl, H.; Wien, W. H. A.; Pham, H. T. M.; Kwakernaak, C.; Knoops, H. C. M.; Kessels, W. M. M.; R. van de Sanden,; Voogt, F. C.; Roozeboom, F.; Sarro, P. M.

    2011-01-01

    One of the critical steps toward producing void-free and uniform bottom-up copper electroplating in high aspect-ratio (AR) through-silicon vias (TSVs) is the ability of the copper electrolyte to spontaneously flow through the entire depth of the via. This can be accomplished by reducing the

  17. Enhancing the wettability of high aspect-ratio through-silicon vias lined with LPCVD silicon nitride or PE-ALD titanium nitride for void-free bottom-up copper electroplating

    NARCIS (Netherlands)

    Saadaoui, M.; Zeijl, H. van; Wien, W.H.A.; Pham, H.T.M.; Kwakernaak, C.; Knoops, H.C.M.; Erwin Kessels, W.M.M.; Sanden, R.M.C.M. van de; Voogt, F.C.; Roozeboom, F.; Sarro, P.M.

    2011-01-01

    One of the critical steps toward producing void-free and uniform bottom-up copper electroplating in high aspect-ratio (AR) through-silicon vias (TSVs) is the ability of the copper electrolyte to spontaneously flow through the entire depth of the via. This can be accomplished by reducing the

  18. Climate variability and demand growth as drivers of water scarcity in the Turkwel river basin: a bottom-up risk assessment of a data-sparse basin in Kenya

    Science.gov (United States)

    Hirpa, F. A.; Dyer, E.; Hope, R.; Dadson, S. J.

    2017-12-01

    Sustainable water management and allocation are essential for maintaining human well-being, sustaining healthy ecosystems, and supporting steady economic growth. The Turkwel river basin, located in north-western Kenya, experiences a high level of water scarcity due to its arid climate, high rainfall variability, and rapidly growing water demand. However, due to sparse hydro-climatic data and limited literature, the water resources system of the basin has been poorly understood. Here we apply a bottom-up climate risk assessment method to estimate the resilience of the basin's water resources system to growing demand and climate stressors. First, using a water resource system model and historical climate data, we construct a climate risk map that depicts the way in which the system responds to climate change and variability. Then we develop a set of water demand scenarios to identify the conditions that potentially lead to the risk of unmet water demand and groundwater depletion. Finally, we investigate the impact of climate change and variability by stress testing these development scenarios against historically strong El Niño/Southern Oscillation (ENSO) years and future climate projections from multiple Global Circulation Models (GCMs). The results reveal that climate variability and increased water demand are the main drivers of water scarcity in the basin. Our findings show that increases in water demand due to expanded irrigation and population growth exert the strongest influence on the ability of the system to meet water resource supply requirements, and in all cases considered increase the impacts of droughts caused by future climate variability. Our analysis illustrates the importance of combining analysis of future climate risks with other development decisions that affect water resources planning. Policy and investment decisions which maximise water use efficiency in the present day are likely to impart resilience to climate change and variability under a

  19. A hybrid modelling approach to simulating foot-and-mouth disease outbreaks in Australian livestock

    Directory of Open Access Journals (Sweden)

    Richard A Bradhurst

    2015-03-01

    Full Text Available Foot-and-mouth disease (FMD is a highly contagious and economically important viral disease of cloven-hoofed animals. Australia's freedom from FMD underpins a valuable trade in live animals and animal products. An outbreak of FMD would result in the loss of export markets and cause severe disruption to domestic markets. The prevention of, and contingency planning for, FMD are of key importance to government, industry, producers and the community. The spread and control of FMD is complex and dynamic due to a highly contagious multi-host pathogen operating in a heterogeneous environment across multiple jurisdictions. Epidemiological modelling is increasingly being recognized as a valuable tool for investigating the spread of disease under different conditions and the effectiveness of control strategies. Models of infectious disease can be broadly classified as: population-based models that are formulated from the top-down and employ population-level relationships to describe individual-level behaviour, individual-based models that are formulated from the bottom-up and aggregate individual-level behaviour to reveal population-level relationships, or hybrid models which combine the two approaches into a single model.The Australian Animal Disease Spread (AADIS hybrid model employs a deterministic equation-based model (EBM to model within-herd spread of FMD, and a stochastic, spatially-explicit agent-based model (ABM to model between-herd spread and control. The EBM provides concise and computationally efficient predictions of herd prevalence and clinical signs over time. The ABM captures the complex, stochastic and heterogeneous environment in which an FMD epidemic operates. The AADIS event-driven hybrid EBM/ABM architecture is a flexible, efficient and extensible framework for modelling the spread and control of disease in livestock on a national scale. We present an overview of the AADIS hybrid approach and a description of the model

  20. Frontotemporal oxyhemoglobin dynamics predict performance accuracy of dance simulation gameplay: temporal characteristics of top-down and bottom-up cortical activities.

    Science.gov (United States)

    Ono, Yumie; Nomoto, Yasunori; Tanaka, Shohei; Sato, Keisuke; Shimada, Sotaro; Tachibana, Atsumichi; Bronner, Shaw; Noah, J Adam

    2014-01-15

    We utilized the high temporal resolution of functional near-infrared spectroscopy to explore how sensory input (visual and rhythmic auditory cues) are processed in the cortical areas of multimodal integration to achieve coordinated motor output during unrestricted dance simulation gameplay. Using an open source clone of the dance simulation video game, Dance Dance Revolution, two cortical regions of interest were selected for study, the middle temporal gyrus (MTG) and the frontopolar cortex (FPC). We hypothesized that activity in the FPC would indicate top-down regulatory mechanisms of motor behavior; while that in the MTG would be sustained due to bottom-up integration of visual and auditory cues throughout the task. We also hypothesized that a correlation would exist between behavioral performance and the temporal patterns of the hemodynamic responses in these regions of interest. Results indicated that greater temporal accuracy of dance steps positively correlated with persistent activation of the MTG and with cumulative suppression of the FPC. When auditory cues were eliminated from the simulation, modifications in cortical responses were found depending on the gameplay performance. In the MTG, high-performance players showed an increase but low-performance players displayed a decrease in cumulative amount of the oxygenated hemoglobin response in the no music condition compared to that in the music condition. In the FPC, high-performance players showed relatively small variance in the activity regardless of the presence of auditory cues, while low-performance players showed larger differences in the activity between the no music and music conditions. These results suggest that the MTG plays an important role in the successful integration of visual and rhythmic cues and the FPC may work as top-down control to compensate for insufficient integrative ability of visual and rhythmic cues in the MTG. The relative relationships between these cortical areas indicated

  1. Transcriptomics-guided bottom-up and top-down venomics of neonate and adult specimens of the arboreal rear-fanged Brown Treesnake, Boiga irregularis, from Guam.

    Science.gov (United States)

    Pla, Davinia; Petras, Daniel; Saviola, Anthony J; Modahl, Cassandra M; Sanz, Libia; Pérez, Alicia; Juárez, Elena; Frietze, Seth; Dorrestein, Pieter C; Mackessy, Stephen P; Calvete, Juan J

    2018-03-01

    neonate and adult B. irregularis from Guam, further highlighting evolutionary trends in venom composition among rear-fanged venomous snakes. The Brown Treesnake (Boiga irregularis) has caused extensive ecological and economic damage to the island of Guam where it has become a classic example of the negative impacts of invasive species. In the current study, we report the first combined transcriptomic and proteomic analysis of B. irregularis venom of Guam origin. The transcriptome of an adult snake contained toxin sequences belonging to 18 protein families, with three-finger toxin (3FTx) isoforms being the most abundant and representing 94% of all venom protein transcript reads. Our bottom-up and top-down venomic analyses confirmed that 3FTxs are the major components of B. irregularis venom, and a comparative analysis of neonate and adult venoms demonstrate a clear ontogenetic shift in toxin abundance, likely driven by dietary variation between the two age classes. Second-generation antivenomics and Western blot analysis using purified anti-Brown Treesnake rabbit serum IgGs (anti-BTS IgGs) showed strong immunoreactivity toward B. irregularis venom. Interestingly, our anti-BTS IgGs did not cross-react with 3FTxs found in several other rear-fanged snake venoms, or against 3FTxs in the venom of the elapid Ophiophagus hannah, indicating that epitopes in these 3FTx molecules are quite distinct. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. First-principles bottom-up study of 1D to 3D magnetic transformation in the copper pyrazine dinitrate S = (1)/(2) antiferromagnetic crystal.

    Science.gov (United States)

    Jornet-Somoza, J; Deumal, M; Robb, M A; Landee, C P; Turnbull, M M; Feyerherm, R; Novoa, J J

    2010-02-15

    On the basis of magnetic susceptibility and heat capacity data, copper pyrazine dinitrate crystal [abbreviated CuPz(NO(3))(2)] has long been considered a good prototype for S = (1)/(2) antiferromagnetic (AFM) Heisenberg chain behavior down to 0.05 K. However, a recent muon-spin rotation experiment indicated the presence of a previously unnoticed 1D to 3D magnetic transition below 0.107 K. Our aim in this work is to perform a rigorous quantitative study of the mechanism of this 1D-3D magnetic transformation, by doing a first-principles bottom-up study of the CuPz(NO(3))(2) crystal at 158 K, where the magnetic properties are clearly 1D, and at 2 K, at which the neutron structure (reported in this work) is considered nearly identical with that below 0.1 K (due to small thermal effects). A change in the magnetic topology is found between these two structures: at 158 K, there are isolated AFM spin chains (J(intra) = -5.23 cm(-1)), while at 2 K, the magnetic chains (J(intra) = -5.96 cm(-1)) weakly interact (the largest of the J(inter) parameters is -0.09 cm(-1)). This change is caused by thermal contraction upon cooling (no crystallographic phase transition is detected down to 2 K, and one will not likely occur below that temperature). The computed and experimental magnetic susceptibility chi(T) curves are nearly identical. The calculated heat capacity C(p)(T) curve has a maximum at 6.92 K, close to the 5.20 K maximum found in the experimental curve at zero external field. In spite of the 3D magnetic topology of the crystal at low temperature, the magnetic susceptibility and heat capacity curves behave as a pure 1D AFM chain in all regions because of the large J(intra)/J(inter) ratio (66.2 in absolute value) and the effect of including the J(inter) interactions will not be easily appreciated in any of these experiments. The impact of the presence of odd- and even-membered regular AFM finite chains in the CuPz(NO(3))(2) crystal has also been evaluated. Odd

  3. A variable resolution right TIN approach for gridded oceanographic data

    Science.gov (United States)

    Marks, David; Elmore, Paul; Blain, Cheryl Ann; Bourgeois, Brian; Petry, Frederick; Ferrini, Vicki

    2017-12-01

    Many oceanographic applications require multi resolution representation of gridded data such as for bathymetric data. Although triangular irregular networks (TINs) allow for variable resolution, they do not provide a gridded structure. Right TINs (RTINs) are compatible with a gridded structure. We explored the use of two approaches for RTINs termed top-down and bottom-up implementations. We illustrate why the latter is most appropriate for gridded data and describe for this technique how the data can be thinned. While both the top-down and bottom-up approaches accurately preserve the surface morphology of any given region, the top-down method of vertex placement can fail to match the actual vertex locations of the underlying grid in many instances, resulting in obscured topology/bathymetry. Finally we describe the use of the bottom-up approach and data thinning in two applications. The first is to provide thinned, variable resolution bathymetry data for tests of storm surge and inundation modeling, in particular hurricane Katrina. Secondly we consider the use of the approach for an application to an oceanographic data grid of 3-D ocean temperature.

  4. Modelling human resource requirements for the nuclear industry in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Roelofs, Ferry [Nuclear Research and Consultancy Group (NRG) (Netherlands); Flore, Massimo; Estorff, Ulrik von [Joint Research Center (JRC) (Netherlands)

    2017-11-15

    The European Human Resource Observatory for Nuclear (EHRO-N) provides the European Commission with essential data related to supply and demand for nuclear experts in the EU-28 and the enlargement and integration countries based on bottom-up information from the nuclear industry. The objective is to assess how the supply of experts for the nuclear industry responds to the needs for the same experts for present and future nuclear projects in the region. Complementary to the bottom-up approach taken by the EHRO-N team at JRC, a top-down modelling approach has been taken in a collaboration with NRG in the Netherlands. This top-down modelling approach focuses on the human resource requirements for operation, construction, decommissioning, and efforts for long term operation of nuclear power plants. This paper describes the top-down methodology, the model input, the main assumptions, and the results of the analyses.

  5. IMI - oral biopharmaceutics tools project - evaluation of bottom-up PBPK prediction success part 1: Characterisation of the OrBiTo database of compounds.

    Science.gov (United States)

    Margolskee, Alison; Darwich, Adam S; Pepin, Xavier; Pathak, Shriram M; Bolger, Michael B; Aarons, Leon; Rostami-Hodjegan, Amin; Angstenberger, Jonas; Graf, Franziska; Laplanche, Loic; Müller, Thomas; Carlert, Sara; Daga, Pankaj; Murphy, Dónal; Tannergren, Christer; Yasin, Mohammed; Greschat-Schade, Susanne; Mück, Wolfgang; Muenster, Uwe; van der Mey, Dorina; Frank, Kerstin Julia; Lloyd, Richard; Adriaenssen, Lieve; Bevernage, Jan; De Zwart, Loeckie; Swerts, Dominique; Tistaert, Christophe; Van Den Bergh, An; Van Peer, Achiel; Beato, Stefania; Nguyen-Trung, Anh-Thu; Bennett, Joanne; McAllister, Mark; Wong, Mei; Zane, Patricia; Ollier, Céline; Vicat, Pascale; Kolhmann, Markus; Marker, Alexander; Brun, Priscilla; Mazuir, Florent; Beilles, Stéphane; Venczel, Marta; Boulenc, Xavier; Loos, Petra; Lennernäs, Hans; Abrahamsson, Bertil

    2017-01-01

    Predicting oral bioavailability (F oral ) is of importance for estimating systemic exposure of orally administered drugs. Physiologically-based pharmacokinetic (PBPK) modelling and simulation have been applied extensively in biopharmaceutics recently. The Oral Biopharmaceutical Tools (OrBiTo) project (Innovative Medicines Initiative) aims to develop and improve upon biopharmaceutical tools, including PBPK absorption models. A large-scale evaluation of PBPK models may be considered the first step. Here we characterise the OrBiTo active pharmaceutical ingredient (API) database for use in a large-scale simulation study. The OrBiTo database comprised 83 APIs and 1475 study arms. The database displayed a median logP of 3.60 (2.40-4.58), human blood-to-plasma ratio of 0.62 (0.57-0.71), and fraction unbound in plasma of 0.05 (0.01-0.17). The database mainly consisted of basic compounds (48.19%) and Biopharmaceutics Classification System class II compounds (55.81%). Median human intravenous clearance was 16.9L/h (interquartile range: 11.6-43.6L/h; n=23), volume of distribution was 80.8L (54.5-239L; n=23). The majority of oral formulations were immediate release (IR: 87.6%). Human F oral displayed a median of 0.415 (0.203-0.724; n=22) for IR formulations. The OrBiTo database was found to be largely representative of previously published datasets. 43 of the APIs were found to satisfy the minimum inclusion criteria for the simulation exercise, and many of these have significant gaps of other key parameters, which could potentially impact the interpretability of the simulation outcome. However, the OrBiTo simulation exercise represents a unique opportunity to perform a large-scale evaluation of the PBPK approach to predicting oral biopharmaceutics. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Infrastructural requirements for local implementation of safety policies: the discordance between top-down and bottom-up systems of action.

    Science.gov (United States)

    Timpka, Toomas; Nordqvist, Cecilia; Lindqvist, Kent

    2009-03-09

    Safety promotion is planned and practised not only by public health organizations, but also by other welfare state agencies, private companies and non-governmental organizations. The term 'infrastructure' originally denoted the underlying resources needed for warfare, e.g. roads, industries, and an industrial workforce. Today, 'infrastructure' refers to the physical elements, organizations and people needed to run projects in different societal arenas. The aim of this study was to examine associations between infrastructure and local implementation of safety policies in injury prevention and safety promotion programs. Qualitative data on municipalities in Sweden designated as Safe Communities were collected from focus group interviews with municipal politicians and administrators, as well as from policy documents, and materials published on the Internet. Actor network theory was used to identify weaknesses in the present infrastructure and determine strategies that can be used to resolve these. The weakness identification analysis revealed that the factual infrastructure available for effectuating national strategies varied between safety areas and approaches, basically reflecting differences between bureaucratic and network-based organizational models. At the local level, a contradiction between safety promotion and the existence of quasi-markets for local public service providers was found to predispose for a poor local infrastructure diminishing the interest in integrated inter-agency activities. The weakness resolution analysis showed that development of an adequate infrastructure for safety promotion would require adjustment of the legal framework regulating injury data exchange, and would also require rational financial models for multi-party investments in local infrastructures. We found that the "silo" structure of government organization and assignment of resources was a barrier to collaborative action for safety at a community level. It may therefore be

  7. Infrastructural requirements for local implementation of safety policies: the discordance between top-down and bottom-up systems of action

    Directory of Open Access Journals (Sweden)

    Lindqvist Kent

    2009-03-01

    Full Text Available Abstract Background Safety promotion is planned and practised not only by public health organizations, but also by other welfare state agencies, private companies and non-governmental organizations. The term 'infrastructure' originally denoted the underlying resources needed for warfare, e.g. roads, industries, and an industrial workforce. Today, 'infrastructure' refers to the physical elements, organizations and people needed to run projects in different societal arenas. The aim of this study was to examine associations between infrastructure and local implementation of safety policies in injury prevention and safety promotion programs. Methods Qualitative data on municipalities in Sweden designated as Safe Communities were collected from focus group interviews with municipal politicians and administrators, as well as from policy documents, and materials published on the Internet. Actor network theory was used to identify weaknesses in the present infrastructure and determine strategies that can be used to resolve these. Results The weakness identification analysis revealed that the factual infrastructure available for effectuating national strategies varied between safety areas and approaches, basically reflecting differences between bureaucratic and network-based organizational models. At the local level, a contradiction between safety promotion and the existence of quasi-markets for local public service providers was found to predispose for a poor local infrastructure diminishing the interest in integrated inter-agency activities. The weakness resolution analysis showed that development of an adequate infrastructure for safety promotion would require adjustment of the legal framework regulating injury data exchange, and would also require rational financial models for multi-party investments in local infrastructures. Conclusion We found that the "silo" structure of government organization and assignment of resources was a barrier to

  8. HEDR modeling approach: Revision 1

    International Nuclear Information System (INIS)

    Shipler, D.B.; Napier, B.A.

    1994-05-01

    This report is a revision of the previous Hanford Environmental Dose Reconstruction (HEDR) Project modeling approach report. This revised report describes the methods used in performing scoping studies and estimating final radiation doses to real and representative individuals who lived in the vicinity of the Hanford Site. The scoping studies and dose estimates pertain to various environmental pathways during various periods of time. The original report discussed the concepts under consideration in 1991. The methods for estimating dose have been refined as understanding of existing data, the scope of pathways, and the magnitudes of dose estimates were evaluated through scoping studies

  9. HEDR modeling approach: Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Shipler, D.B.; Napier, B.A.

    1994-05-01

    This report is a revision of the previous Hanford Environmental Dose Reconstruction (HEDR) Project modeling approach report. This revised report describes the methods used in performing scoping studies and estimating final radiation doses to real and representative individuals who lived in the vicinity of the Hanford Site. The scoping studies and dose estimates pertain to various environmental pathways during various periods of time. The original report discussed the concepts under consideration in 1991. The methods for estimating dose have been refined as understanding of existing data, the scope of pathways, and the magnitudes of dose estimates were evaluated through scoping studies.

  10. Integrating internet GPS vehicle tracking data into a bottom-up vehicular emissions inventory and atmospheric simulation in South-East, Brazil

    Science.gov (United States)

    Ibarra Espinosa, S.; Ynoue, R.; Giannotti, M., , Dr

    2017-12-01

    It has been shown the importance of emissions inventories for air quality studies and environmental planning at local, regional (REAS), hemispheric (CLRTAP) and global (IPCC) scales. It has been shown also that vehicules are becoming the most important sources in urban centers. Several efforts has been made in order to model vehicular emissions to obtain more accurate emission factors based on Vehicular Specific Power (VPS) with IVE and MOVES based on VSP, MOBILE, VERSIT and COPERT based on average speed, or ARTEMIS and HBEFA based on traffic situations. However, little effort has been made to improve traffic activity data. In this study we are proposing using a novel approach to develop vehicular emissions inventory including point data from MAPLINK a company that feeds with traffic data to Google. This includes working and transforming massive amount of data to generate traffic flow and speeds. The region of study is the south east of Brazil including São Paulo metropolitan areas. To estimate vehicular emissions we are using the open source model VEIN available at https://CRAN.R-project.org/package=vein. We generated hourly traffic between 2010-04-21 and 2010-10-22, totalizing 145 hours. This data consists GPS readings from vehicles with assurance policy, applications and other sources. This type data presents spacial bias meaning that only a part of the vehicles are tracked. We corrected this bias using the calculated speed as proxy of traffic flow using measurements of traffic flow and speed per lane made in São Paulo. Then we calibrated the total traffic estimating Fuel Consumption with VEIN and comparing Fuel Sales for the region. We estimated the hourly vehicular emissions and produced emission maps and data-bases. In addition, we simulated atmospheric simulations using WRF-Chem to identify which inventory produces better agreement with air pollutant observations. New technologies and big data provides opportunities to improve vehicular emissions

  11. Modeling Approaches in Planetary Seismology

    Science.gov (United States)

    Weber, Renee; Knapmeyer, Martin; Panning, Mark; Schmerr, Nick

    2014-01-01

    Of the many geophysical means that can be used to probe a planet's interior, seismology remains the most direct. Given that the seismic data gathered on the Moon over 40 years ago revolutionized our understanding of the Moon and are still being used today to produce new insight into the state of the lunar interior, it is no wonder that many future missions, both real and conceptual, plan to take seismometers to other planets. To best facilitate the return of high-quality data from these instruments, as well as to further our understanding of the dynamic processes that modify a planet's interior, various modeling approaches are used to quantify parameters such as the amount and distribution of seismicity, tidal deformation, and seismic structure on and of the terrestrial planets. In addition, recent advances in wavefield modeling have permitted a renewed look at seismic energy transmission and the effects of attenuation and scattering, as well as the presence and effect of a core, on recorded seismograms. In this chapter, we will review these approaches.

  12. IMI - Oral biopharmaceutics tools project - Evaluation of bottom-up PBPK prediction success part 2: An introduction to the simulation exercise and overview of results.

    Science.gov (United States)

    Margolskee, Alison; Darwich, Adam S; Pepin, Xavier; Aarons, Leon; Galetin, Aleksandra; Rostami-Hodjegan, Amin; Carlert, Sara; Hammarberg, Maria; Hilgendorf, Constanze; Johansson, Pernilla; Karlsson, Eva; Murphy, Dónal; Tannergren, Christer; Thörn, Helena; Yasin, Mohammed; Mazuir, Florent; Nicolas, Olivier; Ramusovic, Sergej; Xu, Christine; Pathak, Shriram M; Korjamo, Timo; Laru, Johanna; Malkki, Jussi; Pappinen, Sari; Tuunainen, Johanna; Dressman, Jennifer; Hansmann, Simone; Kostewicz, Edmund; He, Handan; Heimbach, Tycho; Wu, Fan; Hoft, Carolin; Laplanche, Loic; Pang, Yan; Bolger, Michael B; Huehn, Eva; Lukacova, Viera; Mullin, James M; Szeto, Ke X; Costales, Chester; Lin, Jian; McAllister, Mark; Modi, Sweta; Rotter, Charles; Varma, Manthena; Wong, Mei; Mitra, Amitava; Bevernage, Jan; Biewenga, Jeike; Van Peer, Achiel; Lloyd, Richard; Shardlow, Carole; Langguth, Peter; Mishenzon, Irina; Nguyen, Mai Anh; Brown, Jonathan; Lennernäs, Hans; Abrahamsson, Bertil

    2017-01-01

    Orally administered drugs are subject to a number of barriers impacting bioavailability (F oral ), causing challenges during drug and formulation development. Physiologically-based pharmacokinetic (PBPK) modelling can help during drug and formulation development by providing quantitative predictions through a systems approach. The performance of three available PBPK software packages (GI-Sim, Simcyp®, and GastroPlus™) were evaluated by comparing simulated and observed pharmacokinetic (PK) parameters. Since the availability of input parameters was heterogeneous and highly variable, caution is required when interpreting the results of this exercise. Additionally, this prospective simulation exercise may not be representative of prospective modelling in industry, as API information was limited to sparse details. 43 active pharmaceutical ingredients (APIs) from the OrBiTo database were selected for the exercise. Over 4000 simulation output files were generated, representing over 2550 study arm-institution-software combinations and approximately 600 human clinical study arms simulated with overlap. 84% of the simulated study arms represented administration of immediate release formulations, 11% prolonged or delayed release, and 5% intravenous (i.v.). Higher percentages of i.v. predicted area under the curve (AUC) were within two-fold of observed (52.9%) compared to per oral (p.o.) (37.2%), however, F oral and relative AUC (F rel ) between p.o. formulations and solutions were generally well predicted (64.7% and 75.0%). Predictive performance declined progressing from i.v. to solution and immediate release tablet, indicating the compounding error with each layer of complexity. Overall performance was comparable to previous large-scale evaluations. A general overprediction of AUC was observed with average fold error (AFE) of 1.56 over all simulations. AFE ranged from 0.0361 to 64.0 across the 43 APIs, with 25 showing overpredictions. Discrepancies between software

  13. Branding approach and valuation models

    Directory of Open Access Journals (Sweden)

    Mamula Tatjana

    2006-01-01

    Full Text Available Much of the skill of marketing and branding nowadays is concerned with building equity for products whose characteristics, pricing, distribution and availability are really quite close to each other. Brands allow the consumer to shop with confidence. The real power of successful brands is that they meet the expectations of those that buy them or, to put it another way, they represent a promise kept. As such they are a contract between a seller and a buyer: if the seller keeps to its side of the bargain, the buyer will be satisfied; if not, the buyer will in future look elsewhere. Understanding consumer perceptions and associations is an important first step to understanding brand preferences and choices. In this paper, we discuss different models to measure value of brand according to couple of well known approaches according to request by companies. We rely upon several empirical examples.

  14. Principal component approach in variance component estimation for international sire evaluation

    Directory of Open Access Journals (Sweden)

    Jakobsen Jette

    2011-05-01

    Full Text Available Abstract Background The dairy cattle breeding industry is a highly globalized business, which needs internationally comparable and reliable breeding values of sires. The international Bull Evaluation Service, Interbull, was established in 1983 to respond to this need. Currently, Interbull performs multiple-trait across country evaluations (MACE for several traits and breeds in dairy cattle and provides international breeding values to its member countries. Estimating parameters for MACE is challenging since the structure of datasets and conventional use of multiple-trait models easily result in over-parameterized genetic covariance matrices. The number of parameters to be estimated can be reduced by taking into account only the leading principal components of the traits considered. For MACE, this is readily implemented in a random regression model. Methods This article compares two principal component approaches to estimate variance components for MACE using real datasets. The methods tested were a REML approach that directly estimates the genetic principal components (direct PC and the so-called bottom-up REML approach (bottom-up PC, in which traits are sequentially added to the analysis and the statistically significant genetic principal components are retained. Furthermore, this article evaluates the utility of the bottom-up PC approach to determine the appropriate rank of the (covariance matrix. Results Our study demonstrates the usefulness of both approaches and shows that they can be applied to large multi-country models considering all concerned countries simultaneously. These strategies can thus replace the current practice of estimating the covariance components required through a series of analyses involving selected subsets of traits. Our results support the importance of using the appropriate rank in the genetic (covariance matrix. Using too low a rank resulted in biased parameter estimates, whereas too high a rank did not result in

  15. A New Approach to Programming Language Education for Beginners with Top-Down Learning

    Directory of Open Access Journals (Sweden)

    Daisuke Saito

    2013-12-01

    Full Text Available There are two basic approaches in learning new programming language: a bottom-up approach and a top-down approach. It has been said that if a learner has already acquired one language, the top-down approach is more efficient to learn another while, for a person who has absolutely no knowledge of any programming languages; the bottom-up approach is preferable. The major problem of the bottom-up approach is that it requires longer period to acquire the language. For quicker learning, this paper applies a top-down approach for a beginners who has not yet acquired any programming languages.

  16. Closing the gap? Top-down versus bottom-up projections of China's regional energy use and CO2 emissions

    DEFF Research Database (Denmark)

    Dai, Hancheng; Mischke, Peggy; Xie, Xuxuan

    2016-01-01

    and demographic trends as well as a carbon tax pathway, we explore how both models respond to these identical exogenous inputs. Then a soft-linking methodology is applied to "narrow the gap" between the results computed by these models. We find for example that without soft-linking, China's baseline CO2 emissions...... might range from 15-20Gt in 2050, while soft-linking models results in 17Gt. Reasons for the results gap between the models are discussed subsequently, such as model structure and statistical inputs. At a sectoral level, the gap can be mainly traced to China's future coal use in electricity production...

  17. The Chinese electricity access model for rural electrification: Approach, experience and lessons for others

    International Nuclear Information System (INIS)

    Bhattacharyya, Subhes C.; Ohiare, Sanusi

    2012-01-01

    The economic and infrastructural disparities between the rural and urban communities of most developing countries in general and in terms of energy access in particular are quite glaring. China presents a good example of a developing country that has successfully embarked on rural electrification projects over the last few decades and achieved a great feat of almost 100% electrification rate (. World Energy Outlook, 2009, International Energy Agency, Paris (see IEA website at (http://www.worldenergyoutlook.org/electricity.asp).)). The purpose of this paper is to find out how China has achieved this feat; how China’s rural energy projects were financed and whether China provides lessons for other countries to follow. The above questions are examined through an extensive literature review and the paper finds that unlike many other countries following the top-down approach to rural electrification, China has preferred to use a phased development through a bottom-up approach where local resources, and village level development and empowerment played an important role. While the state provided the overall guidance and financial support, the integrated rural development approach has produced local-level solutions that are subsequently integrated to produce an alternative development pathway. Strong government commitment, active local participation, technological flexibility and diversity, strong emphasis on rural development through agricultural and industrial activities and an emphasis on capacity building and training have also played an important role in the success. However, despite achieving the universal access objective, China still faces a number of issues related to rural electricity use, especially in terms of regional use patterns, long-term sustainability of supply and commercial operation of the systems. The Chinese model could serve as an inspiration for other developing countries trying to ensure universal electricity access. - Highlights: ► It

  18. Ecosystem-based fishery management: A critical review of concepts and ecological economic models

    OpenAIRE

    Nguyen, Thanh Viet

    2009-01-01

    An ecosystem approach means different things to different people. As a result the concept of ecosystem-based fishery management is evolving and it has no universal definition or consistent application. As regards ecosystem modeling, most economic models of fishery ignore the linkages to lower trophic levels. In particular, environmental data and other bottom-up information is widely disregarded. The objective of this paper is to provide a critical review of concepts and ecological economic mo...

  19. Non-energy use of fossil fuels and resulting carbon dioxide emissions: bottom-up estimates for the world as a whole and for major developing countries

    NARCIS (Netherlands)

    Weiss, M.; Neelis, M.L.; Blok, K.; Patel, M.K.

    2009-01-01

    We present and apply a simple bottom–up model for estimating non-energy use of fossil fuels and resulting CO2 (carbon dioxide) emissions.We apply this model for the year 2000: (1) to the world as a whole, (2) to the aggregate of Annex I countries and non-Annex I countries, and (3) to the ten

  20. What drives farmers to make top-down or bottom-up adaptation to climate change and fluctuations? A comparative study on 3 cases of apple farming in Japan and South Africa.

    Science.gov (United States)

    Fujisawa, Mariko; Kobayashi, Kazuhiko; Johnston, Peter; New, Mark

    2015-01-01

    Agriculture is one of the most vulnerable sectors to climate change. Farmers have been exposed to multiple stressors including climate change, and they have managed to adapt to those risks. The adaptation actions undertaken by farmers and their decision making are, however, only poorly understood. By studying adaptation practices undertaken by apple farmers in three regions: Nagano and Kazuno in Japan and Elgin in South Africa, we categorize the adaptation actions into two types: farmer initiated bottom-up adaptation and institution led top-down adaptation. We found that the driver which differentiates the type of adaptation likely adopted was strongly related to the farmers' characteristics, particularly their dependence on the institutions, e.g. the farmers' cooperative, in selling their products. The farmers who rely on the farmers' cooperative for their sales are likely to adopt the institution-led adaptation, whereas the farmers who have established their own sales channels tend to start innovative actions by bottom-up. We further argue that even though the two types have contrasting features, the combinations of the both types of adaptations could lead to more successful adaptation particularly in agriculture. This study also emphasizes that more farm-level studies for various crops and regions are warranted to provide substantial feedbacks to adaptation policy.