Sample records for linked function approach
-
Energy Technology Data Exchange (ETDEWEB)
Li, Minjing [School; Qian, Wei-jun [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Gao, Yuqian [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Shi, Liang [School; Liu, Chongxuan [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; School
2017-09-28
The kinetics of biogeochemical processes in natural and engineered environmental systems are typically described using Monod-type or modified Monod-type models. These models rely on biomass as surrogates for functional enzymes in microbial community that catalyze biogeochemical reactions. A major challenge to apply such models is the difficulty to quantitatively measure functional biomass for constraining and validating the models. On the other hand, omics-based approaches have been increasingly used to characterize microbial community structure, functions, and metabolites. Here we proposed an enzyme-based model that can incorporate omics-data to link microbial community functions with biogeochemical process kinetics. The model treats enzymes as time-variable catalysts for biogeochemical reactions and applies biogeochemical reaction network to incorporate intermediate metabolites. The sequences of genes and proteins from metagenomes, as well as those from the UniProt database, were used for targeted enzyme quantification and to provide insights into the dynamic linkage among functional genes, enzymes, and metabolites that are necessary to be incorporated in the model. The application of the model was demonstrated using denitrification as an example by comparing model-simulated with measured functional enzymes, genes, denitrification substrates and intermediates
-
Multi-Functional Fibre-Optic Microwave Links
DEFF Research Database (Denmark)
Gliese, Ulrik Bo
1998-01-01
The multi-functionality of microwave links based on remote heterodyne detection of signals from a dual-frequency laser transmitter is discussed and experimentally demonstrated in this paper. Typically, direct detection in conjunction with optical intensity modulation is used to implement fibre......-optic microwave links. The resulting links are inherently transparent and mainly used for signal transmission. As opposed to direct detection links, remote heterodyne detection links can directly perform functionalities such as modulation, frequency conversion, and transparent signal recovery in addition...
-
Acetone-Linked Peptides: A Convergent Approach for Peptide Macrocyclization and Labeling.
Assem, Naila; Ferreira, David J; Wolan, Dennis W; Dawson, Philip E
2015-07-20
Macrocyclization is a broadly applied approach for overcoming the intrinsically disordered nature of linear peptides. Herein, it is shown that dichloroacetone (DCA) enhances helical secondary structures when introduced between peptide nucleophiles, such as thiols, to yield an acetone-linked bridge (ACE). Aside from stabilizing helical structures, the ketone moiety embedded in the linker can be modified with diverse molecular tags by oxime ligation. Insights into the structure of the tether were obtained through co-crystallization of a constrained S-peptide in complex with RNAse S. The scope of the acetone-linked peptides was further explored through the generation of N-terminus to side chain macrocycles and a new approach for generating fused macrocycles (bicycles). Together, these studies suggest that acetone linking is generally applicable to peptide macrocycles with a specific utility in the synthesis of stabilized helices that incorporate functional tags. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
-
Protein functional links in Trypanosoma brucei, identified by gene fusion analysis
Directory of Open Access Journals (Sweden)
Trimpalis Philip
2011-07-01
Full Text Available Abstract Background Domain or gene fusion analysis is a bioinformatics method for detecting gene fusions in one organism by comparing its genome to that of other organisms. The occurrence of gene fusions suggests that the two original genes that participated in the fusion are functionally linked, i.e. their gene products interact either as part of a multi-subunit protein complex, or in a metabolic pathway. Gene fusion analysis has been used to identify protein functional links in prokaryotes as well as in eukaryotic model organisms, such as yeast and Drosophila. Results In this study we have extended this approach to include a number of recently sequenced protists, four of which are pathogenic, to identify fusion linked proteins in Trypanosoma brucei, the causative agent of African sleeping sickness. We have also examined the evolution of the gene fusion events identified, to determine whether they can be attributed to fusion or fission, by looking at the conservation of the fused genes and of the individual component genes across the major eukaryotic and prokaryotic lineages. We find relatively limited occurrence of gene fusions/fissions within the protist lineages examined. Our results point to two trypanosome-specific gene fissions, which have recently been experimentally confirmed, one fusion involving proteins involved in the same metabolic pathway, as well as two novel putative functional links between fusion-linked protein pairs. Conclusions This is the first study of protein functional links in T. brucei identified by gene fusion analysis. We have used strict thresholds and only discuss results which are highly likely to be genuine and which either have already been or can be experimentally verified. We discuss the possible impact of the identification of these novel putative protein-protein interactions, to the development of new trypanosome therapeutic drugs.
-
Biocatalytic cross-linking of pectic polysaccharides for designed food functionality
DEFF Research Database (Denmark)
Zaidel, Dayang Norulfairuz Abang; Meyer, Anne S.
2012-01-01
the mechanisms of formation of functional pectic polysaccharide cross-links, including covalent cross-links (notably phenolic esters and uronyl ester linkages) and non-covalent, ionic cross-links (which involve calcium and borate ester links). The treatise examines how such cross-links can be designed via......Recent research has demonstrated how cross-linking of pectic polysaccharides to obtain gel formation can be promoted by enzymatic catalysis reactions, and provide opportunities for functional upgrading of pectic polysaccharides present in agro-industrial sidestreams. This review highlights...... specific enzymatic reactions, and highlights the most recent data concerning enzyme catalyzed engineering of cross-links for in situ structural design of functional properties of foods....
-
A novel time series link prediction method: Learning automata approach
Moradabadi, Behnaz; Meybodi, Mohammad Reza
2017-09-01
Link prediction is a main social network challenge that uses the network structure to predict future links. The common link prediction approaches to predict hidden links use a static graph representation where a snapshot of the network is analyzed to find hidden or future links. For example, similarity metric based link predictions are a common traditional approach that calculates the similarity metric for each non-connected link and sort the links based on their similarity metrics and label the links with higher similarity scores as the future links. Because people activities in social networks are dynamic and uncertainty, and the structure of the networks changes over time, using deterministic graphs for modeling and analysis of the social network may not be appropriate. In the time-series link prediction problem, the time series link occurrences are used to predict the future links In this paper, we propose a new time series link prediction based on learning automata. In the proposed algorithm for each link that must be predicted there is one learning automaton and each learning automaton tries to predict the existence or non-existence of the corresponding link. To predict the link occurrence in time T, there is a chain consists of stages 1 through T - 1 and the learning automaton passes from these stages to learn the existence or non-existence of the corresponding link. Our preliminary link prediction experiments with co-authorship and email networks have provided satisfactory results when time series link occurrences are considered.
-
Linking Data and Publications: Towards a Cross-Disciplinary Approach
Directory of Open Access Journals (Sweden)
Maarten Hoogerwerf
2013-06-01
Full Text Available In this paper, we tackle the challenge of linking scholarly information in multi-disciplinary research infrastructures. There is a trend towards linking publications with research data and other information, but, as it is still emerging, this is handled differently by various initiatives and disciplines. For OpenAIRE, a European cross-disciplinary publication infrastructure, this poses the challenge of supporting these heterogeneous practices. Hence, OpenAIRE wants to contribute to the development of a common approach for discipline-independent linking practices between publications, data, project information and researchers. To this end, we constructed two demonstrators to identify commonalities and differences. The results show the importance of stable and unique identifiers, and support a ‘by reference’ approach of interlinking research results. This approach allows discipline-specific research information to be managed independently in distributed systems and avoids redundant maintenance. Furthermore, it allows these disciplinary systems to manage the specialized structures of their contents themselves.
-
Marco-Ruiz, Luis; Pedrinaci, Carlos; Maldonado, J A; Panziera, Luca; Chen, Rong; Bellika, J Gustav
2016-08-01
The high costs involved in the development of Clinical Decision Support Systems (CDSS) make it necessary to share their functionality across different systems and organizations. Service Oriented Architectures (SOA) have been proposed to allow reusing CDSS by encapsulating them in a Web service. However, strong barriers in sharing CDS functionality are still present as a consequence of lack of expressiveness of services' interfaces. Linked Services are the evolution of the Semantic Web Services paradigm to process Linked Data. They aim to provide semantic descriptions over SOA implementations to overcome the limitations derived from the syntactic nature of Web services technologies. To facilitate the publication, discovery and interoperability of CDS services by evolving them into Linked Services that expose their interfaces as Linked Data. We developed methods and models to enhance CDS SOA as Linked Services that define a rich semantic layer based on machine interpretable ontologies that powers their interoperability and reuse. These ontologies provided unambiguous descriptions of CDS services properties to expose them to the Web of Data. We developed models compliant with Linked Data principles to create a semantic representation of the components that compose CDS services. To evaluate our approach we implemented a set of CDS Linked Services using a Web service definition ontology. The definitions of Web services were linked to the models developed in order to attach unambiguous semantics to the service components. All models were bound to SNOMED-CT and public ontologies (e.g. Dublin Core) in order to count on a lingua franca to explore them. Discovery and analysis of CDS services based on machine interpretable models was performed reasoning over the ontologies built. Linked Services can be used effectively to expose CDS services to the Web of Data by building on current CDS standards. This allows building shared Linked Knowledge Bases to provide machine
-
Enns, Eva A; Brandeau, Margaret L
2015-04-21
For many communicable diseases, knowledge of the underlying contact network through which the disease spreads is essential to determining appropriate control measures. When behavior change is the primary intervention for disease prevention, it is important to understand how to best modify network connectivity using the limited resources available to control disease spread. We describe and compare four algorithms for selecting a limited number of links to remove from a network: two "preventive" approaches (edge centrality, R0 minimization), where the decision of which links to remove is made prior to any disease outbreak and depends only on the network structure; and two "reactive" approaches (S-I edge centrality, optimal quarantining), where information about the initial disease states of the nodes is incorporated into the decision of which links to remove. We evaluate the performance of these algorithms in minimizing the total number of infections that occur over the course of an acute outbreak of disease. We consider different network structures, including both static and dynamic Erdös-Rényi random networks with varying levels of connectivity, a real-world network of residential hotels connected through injection drug use, and a network exhibiting community structure. We show that reactive approaches outperform preventive approaches in averting infections. Among reactive approaches, removing links in order of S-I edge centrality is favored when the link removal budget is small, while optimal quarantining performs best when the link removal budget is sufficiently large. The budget threshold above which optimal quarantining outperforms the S-I edge centrality algorithm is a function of both network structure (higher for unstructured Erdös-Rényi random networks compared to networks with community structure or the real-world network) and disease infectiousness (lower for highly infectious diseases). We conduct a value-of-information analysis of knowing which
-
a Web Service Approach for Linking Sensors and Cellular Spaces
Isikdag, U.
2013-09-01
More and more devices are starting to be connected to the Internet. In the future the Internet will not only be a communication medium for people, it will in fact be a communication environment for devices. The connected devices which are also referred as Things will have an ability to interact with other devices over the Internet, i.) provide information in interoperable form and ii.) consume /utilize such information with the help of sensors embedded in them. This overall concept is known as Internet-of- Things (IoT). This requires new approaches to be investigated for system architectures to establish relations between spaces and sensors. The research presented in this paper elaborates on an architecture developed with this aim, i.e. linking spaces and sensors using a RESTful approach. The objective is making spaces aware of (sensor-embedded) devices, and making devices aware of spaces in a loosely coupled way (i.e. a state/usage/function change in the spaces would not have effect on sensors, similarly a location/state/usage/function change in sensors would not have any effect on spaces). The proposed architecture also enables the automatic assignment of sensors to spaces depending on space geometry and sensor location.
-
A Novel Synchronization-Based Approach for Functional Connectivity Analysis
Directory of Open Access Journals (Sweden)
Angela Lombardi
2017-01-01
Full Text Available Complex network analysis has become a gold standard to investigate functional connectivity in the human brain. Popular approaches for quantifying functional coupling between fMRI time series are linear zero-lag correlation methods; however, they might reveal only partial aspects of the functional links between brain areas. In this work, we propose a novel approach for assessing functional coupling between fMRI time series and constructing functional brain networks. A phase space framework is used to map couples of signals exploiting their cross recurrence plots (CRPs to compare the trajectories of the interacting systems. A synchronization metric is extracted from the CRP to assess the coupling behavior of the time series. Since the functional communities of a healthy population are expected to be highly consistent for the same task, we defined functional networks of task-related fMRI data of a cohort of healthy subjects and applied a modularity algorithm in order to determine the community structures of the networks. The within-group similarity of communities is evaluated to verify whether such new metric is robust enough against noise. The synchronization metric is also compared with Pearson’s correlation coefficient and the detected communities seem to better reflect the functional brain organization during the specific task.
-
Flexible link functions in nonparametric binary regression with Gaussian process priors.
Li, Dan; Wang, Xia; Lin, Lizhen; Dey, Dipak K
2016-09-01
In many scientific fields, it is a common practice to collect a sequence of 0-1 binary responses from a subject across time, space, or a collection of covariates. Researchers are interested in finding out how the expected binary outcome is related to covariates, and aim at better prediction in the future 0-1 outcomes. Gaussian processes have been widely used to model nonlinear systems; in particular to model the latent structure in a binary regression model allowing nonlinear functional relationship between covariates and the expectation of binary outcomes. A critical issue in modeling binary response data is the appropriate choice of link functions. Commonly adopted link functions such as probit or logit links have fixed skewness and lack the flexibility to allow the data to determine the degree of the skewness. To address this limitation, we propose a flexible binary regression model which combines a generalized extreme value link function with a Gaussian process prior on the latent structure. Bayesian computation is employed in model estimation. Posterior consistency of the resulting posterior distribution is demonstrated. The flexibility and gains of the proposed model are illustrated through detailed simulation studies and two real data examples. Empirical results show that the proposed model outperforms a set of alternative models, which only have either a Gaussian process prior on the latent regression function or a Dirichlet prior on the link function. © 2015, The International Biometric Society.
-
Multiple Time Series Forecasting Using Quasi-Randomized Functional Link Neural Networks
Directory of Open Access Journals (Sweden)
Thierry Moudiki
2018-03-01
Full Text Available We are interested in obtaining forecasts for multiple time series, by taking into account the potential nonlinear relationships between their observations. For this purpose, we use a specific type of regression model on an augmented dataset of lagged time series. Our model is inspired by dynamic regression models (Pankratz 2012, with the response variable’s lags included as predictors, and is known as Random Vector Functional Link (RVFL neural networks. The RVFL neural networks have been successfully applied in the past, to solving regression and classification problems. The novelty of our approach is to apply an RVFL model to multivariate time series, under two separate regularization constraints on the regression parameters.
-
A hybrid linked data approach to support asset management
Luiten, G.T.; Bohms, H.M.; O'Keeffe, A.; Nederveen, S. van; Bakker, J.; Wikstrom, L.
2016-01-01
This paper evaluates experiences with applying a linked data approach for coping with the many challenges for information management in asset management from the perspective of National Road Authorities (NRAs). As influential players, NRAs are often the initiators of innovation in the civil
-
DEFF Research Database (Denmark)
Siebner, H R; Callicott, J H; Sommer, T
2009-01-01
In recent years, an array of brain mapping techniques has been successfully employed to link individual differences in circuit function or structure in the living human brain with individual variations in the human genome. Several proof-of-principle studies provided converging evidence that brain...... imaging can establish important links between genes and behaviour. The overarching goal is to use genetically informed brain imaging to pinpoint neurobiological mechanisms that contribute to behavioural intermediate phenotypes or disease states. This special issue on "Linking Genes to Brain Function...... in Health and Disease" provides an overview over how the "imaging genetics" approach is currently applied in the various fields of systems neuroscience to reveal the genetic underpinnings of complex behaviours and brain diseases. While the rapidly emerging field of imaging genetics holds great promise...
-
Link Performance Analysis and monitoring - A unified approach to divergent requirements
Thom, G. A.
Link Performance Analysis and real-time monitoring are generally covered by a wide range of equipment. Bit Error Rate testers provide digital link performance measurements but are not useful during real-time data flows. Real-time performance monitors utilize the fixed overhead content but vary widely from format to format. Link quality information is also present from signal reconstruction equipment in the form of receiver AGC, bit synchronizer AGC, and bit synchronizer soft decision level outputs, but no general approach to utilizing this information exists. This paper presents an approach to link tests, real-time data quality monitoring, and results presentation that utilizes a set of general purpose modules in a flexible architectural environment. The system operates over a wide range of bit rates (up to 150 Mbs) and employs several measurement techniques, including P/N code errors or fixed PCM format errors, derived real-time BER from frame sync errors, and Data Quality Analysis derived by counting significant sync status changes. The architecture performs with a minimum of elements in place to permit a phased update of the user's unit in accordance with his needs.
-
Gordon, John
2014-05-01
The ecosystem approach is now a key driver for conservation policy globally. By definition an ecosystem includes both abiotic and biotic components interacting as a functional unit. However, the role of geodiversity generally remains poorly recognised both at a policy level and in the practical management of protected areas. This presentation examines key links between geodiversity and biodiversity, and demonstrates the benefits of better integration both to enhance conservation of geoheritage and the role of geodiversity in ecosystem management. Geodiversity contributes essentially to most of the ecosystem services recognised in the Millennium Ecosystem Assessment. It underpins biodiversity from micro- to macro-scales through the influence of factors such as lithology, topography, sediments, soils and hydrology. Most habitats and species depend on the abiotic 'stage' on which they exist. Active geological processes also help to determine the heterogeneity of the physical environment, creating mosaics of landforms, surface deposits and dynamic environments that support a range of biodiversity. In the face of climate change and other human pressures, maintaining and enhancing geodiversity should help to 'future-proof' biodiversity in the longer term. Learning from the past through palaeoenvironmental records can also enable better understanding of ecosystem dynamics. As well as recognising the value of geoheritage in its own right, a more integrated approach to conservation in protected areas would benefit both biodiversity and geodiversity, incorporating the concept of 'conserving the stage' (Anderson & Ferree, 2010) and the maintenance of natural processes. As part of developing the scientific framework of geodiversity, this requires geoscience engagement in the ecosystem approach, including evidence-based interdisciplinary research on the functional links between geodiversity and biodiversity across a range of spatial and temporal scales both to inform policy and
-
Linking biogeomorphic feedbacks from ecosystem engineer to landscape scale: a panarchy approach
Eichel, Jana
2017-04-01
Scale is a fundamental concept in both ecology and geomorphology. Therefore, scale-based approaches are a valuable tool to bridge the disciplines and improve the understanding of feedbacks between geomorphic processes, landforms, material and organisms and ecological processes in biogeomorphology. Yet, linkages between biogeomorphic feedbacks on different scales, e.g. between ecosystem engineering and landscape scale patterns and dynamics, are not well understood. A panarchy approach sensu Holling et al. (2002) can help to close this research gap and explain how structure and function are created in biogeomorphic ecosystems. Based on results from previous biogeomorphic research in Turtmann glacier foreland (Switzerland; Eichel, 2017; Eichel et al. 2013, 2016), a panarchy concept is presented for lateral moraine slope biogeomorphic ecosystems. It depicts biogeomorphic feedbacks on different spatiotemporal scales as a set of nested adaptive cycles and links them by 'remember' and 'revolt' connections. On a small scale (cm2 - m2; seconds to years), the life cycle of the ecosystem engineer Dryas octopetala L. is considered as an adaptive cycle. Biogeomorphic succession within patches created by geomorphic processes represents an intermediate scale adaptive cycle (m2 - ha, years to decades), while geomorphic and ecologic pattern development at a landscape scale (ha - km2, decades to centuries) can be illustrated by an adaptive cycle of ‚biogeomorphic patch dynamics' (Eichel, 2017). In the panarchy, revolt connections link the smaller scale adaptive cycles to larger scale cycles: on lateral moraine slopes, the development of ecosystem engineer biomass and cover controls the engineering threshold of the biogeomorphic feedback window (Eichel et al., 2016) and therefore the onset of the biogeomorphic phase during biogeomorphic succession. In this phase, engineer patches and biogeomorphic structures can be created in the patch mosaic of the landscape. Remember connections
-
New approaches to e-reserve linking, sharing and streaming
Cheung, Ophelia; Patrick, Susan
2010-01-01
Aimed at academic library practitioners, this book describes how e-reserve services can evolve and adapt to the changing virtual learning environment of higher education. New approaches discussed include: the integration of subscribed, free, and copyrighted resources within course management systems; innovative employment of open URL link resolvers to connect e-reserve with library e-resources and services; video streaming within course documents; and the creative use of bibliographic software to produce customized reading lists. New Approaches to E-Reserve includes detailed descriptions and e
-
Nonlinear degradation of a visible-light communication link: A Volterra-series approach
Kamalakis, Thomas; Dede, Georgia
2018-06-01
Visible light communications can be used to provide illumination and data communication at the same time. In this paper, a reverse-engineering approach is presented for assessing the impact of nonlinear signal distortion in visible light communication links. The approach is based on the Volterra series expansion and has the advantage of accurately accounting for memory effects in contrast to the static nonlinear models that are popular in the literature. Volterra kernels describe the end-to-end system response and can be inferred from measurements. Consequently, this approach does not rely on any particular physical models and assumptions regarding the individual link components. We provide the necessary framework for estimating the nonlinear distortion on the symbol estimates of a discrete multitone modulated link. Various design aspects such as waveform clipping and predistortion are also incorporated in the analysis. Using this framework, the nonlinear signal-to-interference is calculated for the system at hand. It is shown that at high signal amplitudes, the nonlinear signal-to-interference can be less than 25 dB.
-
Socioeconomic Risk Moderates the Link between Household Chaos and Maternal Executive Function
Deater-Deckard, Kirby; Chen, Nan; Wang, Zhe; Bell, Martha Ann
2012-01-01
We examined the link between household chaos (i.e., noise, clutter, disarray, lack of routines) and maternal executive function (i.e., effortful regulation of attention and memory), and whether it varied as a function of socioeconomic risk (i.e., single parenthood, lower mother and father educational attainment, housing situation, and father unemployment). We hypothesized that: 1) higher levels of household chaos would be linked with poorer maternal executive function, even when controlling for other measures of cognitive functioning (e.g., verbal ability), and 2) this link would be strongest in the most socioeconomically distressed or lowest-socioeconomic status households. The diverse sample included 153 mothers from urban and rural areas who completed a questionnaire and a battery of cognitive executive function tasks and a verbal ability task in the laboratory. Results were mixed for hypothesis 1, and consistent with hypothesis 2. Two-thirds of the variance overlapped between household chaos and maternal executive function, but only in families with high levels of socioeconomic risk. This pattern was not found for chaos and maternal verbal ability, suggesting that the potentially deleterious effects of household chaos may be specific to maternal executive function. The findings implicate household chaos as a powerful statistical predictor of maternal executive function in socioeconomically distressed contexts. PMID:22563703
-
Study on predicting residual life of elevator links by fracture mechanics approach
Energy Technology Data Exchange (ETDEWEB)
Li Helin; Zhang Yi; Deng Zengjie [China National Petroleum Corp., Xi`an, Shaanxi (China). Tubular Goods Research Center; Jin Dazeng [Xi`an Jiaotong Univ., Xi`an, Shaanxi (China)
1995-12-31
On the basis of investigation, failure and fracture analysis of elevator links, residual life prediction of links using fracture mechanics approach is studied, and mechanical properties, fracture toughness value K{sub IC} and fatigue crack propagation rage da/dN of the steel for elevator links are determined. Using the relation between stress intensity factor K{sub I} and the strain-energy release rate, the two-dimensional conversion thickness finite element method has been used to calculate the stress intensity factors K{sub I} for dangerous sections in the ring part of links. Furthermore, the reliability of calculations of the finite element stress intensity factors K{sub I} for dangerous sections of elevator links and the residual life computation for links are verified by fatigue tests of actual links. Finally, the experimental verification of computed results by 150T link fractured at site indicates that the computed critical crack lengths and residual life tally well with those measured and meet the needs of oil drilling.
-
Super-resolution links vinculin localization to function in focal adhesions.
Giannone, Grégory
2015-07-01
Integrin-based focal adhesions integrate biochemical and biomechanical signals from the extracellular matrix and the actin cytoskeleton. The combination of three-dimensional super-resolution imaging and loss- or gain-of-function protein mutants now links the nanoscale dynamic localization of proteins to their activation and function within focal adhesions.
-
Polgar, L. M.; Fortunato, G.; Araya-Hermosilla, R.; van Duin, M.; Pucci, A.; Picchioni, F.
Furan-functionalized polyketone (PK-FU) was added to a furan-functionalized ethylene-propylene rubber (EPM-FU). The mixture was subsequently cross-linked with a bismaleimide through Diels-Alder chemistry in order to improve the mechanical properties of the rubber. Infrared spectroscopy showed the
-
Effective teaching: Linking teaching to learning functions | Grösser ...
African Journals Online (AJOL)
In this regard, it is important that teachers are able to link teaching to learning functions in order to facilitate the optimal realization of learning outcomes. In this study the extent to which teaching assists the development of learning functions was examined by means of a quantitative research project. The findings indicated ...
-
Socioeconomic risk moderates the link between household chaos and maternal executive function.
Deater-Deckard, Kirby; Chen, Nan; Wang, Zhe; Bell, Martha Ann
2012-06-01
We examined the link between household chaos (i.e., noise, clutter, disarray, lack of routines) and maternal executive function (i.e., effortful regulation of attention and memory), and whether it varied as a function of socioeconomic risk (i.e., single parenthood, lower mother and father educational attainment, housing situation, and father unemployment). We hypothesized that: 1) higher levels of household chaos would be linked with poorer maternal executive function, even when controlling for other measures of cognitive functioning (e.g., verbal ability), and 2) this link would be strongest in the most socioeconomically distressed or lowest-socioeconomic status households. The diverse sample included 153 mothers from urban and rural areas who completed a questionnaire and a battery of cognitive executive function tasks and a verbal ability task in the laboratory. Results were mixed for Hypothesis 1, and consistent with Hypothesis 2. Two-thirds of the variance overlapped between household chaos and maternal executive function, but only in families with high levels of socioeconomic risk. This pattern was not found for chaos and maternal verbal ability, suggesting that the potentially deleterious effects of household chaos may be specific to maternal executive function. The findings implicate household chaos as a powerful statistical predictor of maternal executive function in socioeconomically distressed contexts. PsycINFO Database Record (c) 2012 APA, all rights reserved.
-
Hacking 360 Link: A hybrid approach
Directory of Open Access Journals (Sweden)
John Durno
2012-10-01
Full Text Available When the University of Victoria Libraries switched from a locally-hosted link resolver (SFX to a vendor-hosted link resolver (360Link, new strategies were required to effectively integrate the vendor-hosted link resolver with the Libraries' other systems and services. Custom javascript is used to add links to the 360Link page; these links then point at local PHP code running on UVic servers, which can then redirect to appropriate local service or display a form directly. An open source PHP OpenURL parser class is announced. Consideration is given to the importance of maintaining open protocols and standards in the transition to vendor-hosted services.
-
A Weakest-Link Approach for Fatigue Limit of 30CrNiMo8 Steels (Preprint)
2011-03-01
34Application of a Weakest-Link Concept to the Fatigue Limit of the Bearing Steel Sae 52100 in a Bainitic Condition," Fatigue and Fracture of...AFRL-RX-WP-TP-2011-4206 A WEAKEST-LINK APPROACH FOR FATIGUE LIMIT OF 30CrNiMo8 STEELS (PREPRINT) S. Ekwaro-Osire and H.V. Kulkarni Texas...2011 4. TITLE AND SUBTITLE A WEAKEST-LINK APPROACH FOR FATIGUE LIMIT OF 30CrNiMo8 STEELS (PREPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT
-
Midlife managerial experience is linked to late life hippocampal morphology and function.
Suo, C; Gates, N; Fiatarone Singh, M; Saigal, N; Wilson, G C; Meiklejohn, J; Sachdev, P; Brodaty, H; Wen, W; Singh, N; Baune, B T; Baker, M; Foroughi, N; Wang, Y; Valenzuela, Michael J
2017-04-01
An active cognitive lifestyle has been suggested to have a protective role in the long-term maintenance of cognition. Amongst healthy older adults, more managerial or supervisory experiences in midlife are linked to a slower hippocampal atrophy rate in late life. Yet whether similar links exist in individuals with Mild Cognitive Impairment (MCI) is not known, nor whether these differences have any functional implications. 68 volunteers from the Sydney SMART Trial, diagnosed with non-amnestic MCI, were divided into high and low managerial experience (HME/LME) during their working life. All participants underwent neuropsychological testing, structural and resting-state functional MRI. Group comparisons were performed on hippocampal volume, morphology, hippocampal seed-based functional connectivity, memory and executive function and self-ratings of memory proficiency. HME was linked to better memory function (p = 0.024), mediated by larger hippocampal volume (p = 0.025). More specifically, deformation analysis found HME had relatively more volume in the CA1 sub-region of the hippocampus (p < 0.05). Paradoxically, this group rated their memory proficiency worse (p = 0.004), a result correlated with diminished functional connectivity between the right hippocampus and right prefrontal cortex (p < 0.001). Finally, hierarchical regression modelling substantiated this double dissociation.
-
A Novel Topology Link-Controlling Approach for Active Defense of a Node in a Network
Directory of Open Access Journals (Sweden)
Jun Li
2017-03-01
Full Text Available With the rapid development of virtual machine technology and cloud computing, distributed denial of service (DDoS attacks, or some peak traffic, poses a great threat to the security of the network. In this paper, a novel topology link control technique and mitigation attacks in real-time environments is proposed. Firstly, a non-invasive method of deploying virtual sensors in the nodes is built, which uses the resource manager of each monitored node as a sensor. Secondly, a general topology-controlling approach of resisting the tolerant invasion is proposed. In the proposed approach, a prediction model is constructed by using copula functions for predicting the peak of a resource through another resource. The result of prediction determines whether or not to initiate the active defense. Finally, a minority game with incomplete strategy is employed to suppress attack flows and improve the permeability of the normal flows. The simulation results show that the proposed approach is very effective in protecting nodes.
-
X-linked inhibitor of apoptosis regulates T cell effector function
DEFF Research Database (Denmark)
Zehntner, Simone P; Bourbonnière, Lyne; Moore, Craig S
2007-01-01
To understand how the balance between pro- and anti-apoptotic signals influences effector function in the immune system, we studied the X-linked inhibitor of apoptosis (XIAP), an endogenous regulator of cellular apoptosis. Real-time PCR showed increased XIAP expression in blood of mice with exper......To understand how the balance between pro- and anti-apoptotic signals influences effector function in the immune system, we studied the X-linked inhibitor of apoptosis (XIAP), an endogenous regulator of cellular apoptosis. Real-time PCR showed increased XIAP expression in blood of mice...... dramatically reduced within the CNS. Flow cytometry showed an 88-93% reduction in T cells. The proportion of TUNEL(+) apoptotic CD4(+) T cells in the CNS was increased from Neurons...... and oligodendrocytes were not affected; neither did apoptosis increase in liver, where XIAP knockdown also occurred. ASO-XIAP increased susceptibility of T cells to activation-induced apoptosis in vitro. Our results identify XIAP as a critical controller of apoptotic susceptibility of effector T cell function...
-
The XML approach to implementing space link extension service management
Tai, W.; Welz, G. A.; Theis, G.; Yamada, T.
2001-01-01
A feasibility study has been conducted at JPL, ESOC, and ISAS to assess the possible applications of the eXtensible Mark-up Language (XML) capabilities to the implementation of the CCSDS Space Link Extension (SLE) Service Management function.
-
Directory of Open Access Journals (Sweden)
M. Kumar
2016-01-01
Full Text Available Gaussian noise is one of the dominant noises, which degrades the quality of acquired Computed Tomography (CT image data. It creates difficulties in pathological identification or diagnosis of any disease. Gaussian noise elimination is desirable to improve the clarity of a CT image for clinical, diagnostic, and postprocessing applications. This paper proposes an evolutionary nonlinear adaptive filter approach, using Cat Swarm Functional Link Artificial Neural Network (CS-FLANN to remove the unwanted noise. The structure of the proposed filter is based on the Functional Link Artificial Neural Network (FLANN and the Cat Swarm Optimization (CSO is utilized for the selection of optimum weight of the neural network filter. The applied filter has been compared with the existing linear filters, like the mean filter and the adaptive Wiener filter. The performance indices, such as peak signal to noise ratio (PSNR, have been computed for the quantitative analysis of the proposed filter. The experimental evaluation established the superiority of the proposed filtering technique over existing methods.
-
Synthesis of Cross-Linked Polymeric Micelle pH Nanosensors
DEFF Research Database (Denmark)
Ek, Pramod Kumar; Jølck, Rasmus Irming; Andresen, Thomas Lars
2015-01-01
The design flexibility that polymeric micelles offer in the fabrication of optical nanosensors for ratiometric pH measurements is investigated. pH nanosensors based on polymeric micelles are synthesized either by a mixed-micellization approach or by a postmicelle modification strategy. In the mixed......-micellization approach, self-assembly of functionalized unimers followed by shell cross-linking by copper-catalyzed azide-alkyne cycloaddition (CuAAC) results in stabilized cRGD-functionalized micelle pH nanosensors. In the postmicelle modification strategy, simultaneous cross-linking and fluorophore conjugation...... at the micelle shell using CuAAC results in a stabilized micelle pH nanosensor. Compared to the postmicelle modification strategy, the mixed-micellization approach increases the control of the overall composition of the nanosensors.Both approaches provide stable nanosensors with similar pKa profiles and thereby...
-
Link prediction via generalized coupled tensor factorisation
DEFF Research Database (Denmark)
Ermiş, Beyza; Evrim, Acar Ataman; Taylan Cemgil, A.
2012-01-01
and higher-order tensors. We propose to use an approach based on probabilistic interpretation of tensor factorisation models, i.e., Generalised Coupled Tensor Factorisation, which can simultaneously fit a large class of tensor models to higher-order tensors/matrices with com- mon latent factors using...... different loss functions. Numerical experiments demonstrate that joint analysis of data from multiple sources via coupled factorisation improves the link prediction performance and the selection of right loss function and tensor model is crucial for accurately predicting missing links....
-
Dal Maschio, Marco; Donovan, Joseph C; Helmbrecht, Thomas O; Baier, Herwig
2017-05-17
We introduce a flexible method for high-resolution interrogation of circuit function, which combines simultaneous 3D two-photon stimulation of multiple targeted neurons, volumetric functional imaging, and quantitative behavioral tracking. This integrated approach was applied to dissect how an ensemble of premotor neurons in the larval zebrafish brain drives a basic motor program, the bending of the tail. We developed an iterative photostimulation strategy to identify minimal subsets of channelrhodopsin (ChR2)-expressing neurons that are sufficient to initiate tail movements. At the same time, the induced network activity was recorded by multiplane GCaMP6 imaging across the brain. From this dataset, we computationally identified activity patterns associated with distinct components of the elicited behavior and characterized the contributions of individual neurons. Using photoactivatable GFP (paGFP), we extended our protocol to visualize single functionally identified neurons and reconstruct their morphologies. Together, this toolkit enables linking behavior to circuit activity with unprecedented resolution. Copyright © 2017 Elsevier Inc. All rights reserved.
-
Bayesian inference in an item response theory model with a generalized student t link function
Azevedo, Caio L. N.; Migon, Helio S.
2012-10-01
In this paper we introduce a new item response theory (IRT) model with a generalized Student t-link function with unknown degrees of freedom (df), named generalized t-link (GtL) IRT model. In this model we consider only the difficulty parameter in the item response function. GtL is an alternative to the two parameter logit and probit models, since the degrees of freedom (df) play a similar role to the discrimination parameter. However, the behavior of the curves of the GtL is different from those of the two parameter models and the usual Student t link, since in GtL the curve obtained from different df's can cross the probit curves in more than one latent trait level. The GtL model has similar proprieties to the generalized linear mixed models, such as the existence of sufficient statistics and easy parameter interpretation. Also, many techniques of parameter estimation, model fit assessment and residual analysis developed for that models can be used for the GtL model. We develop fully Bayesian estimation and model fit assessment tools through a Metropolis-Hastings step within Gibbs sampling algorithm. We consider a prior sensitivity choice concerning the degrees of freedom. The simulation study indicates that the algorithm recovers all parameters properly. In addition, some Bayesian model fit assessment tools are considered. Finally, a real data set is analyzed using our approach and other usual models. The results indicate that our model fits the data better than the two parameter models.
-
Linking adult hippocampal neurogenesis with human physiology and disease.
Bowers, Megan; Jessberger, Sebastian
2016-07-01
We here review the existing evidence linking adult hippocampal neurogenesis and human brain function in physiology and disease. Furthermore, we aim to point out where evidence is missing, highlight current promising avenues of investigation, and suggest future tools and approaches to foster the link between life-long neurogenesis and human brain function. Developmental Dynamics 245:702-709, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
-
Radke, Sina; Seidel, Eva-Maria; Eickhoff, Simon B; Gur, Ruben C; Schneider, Frank; Habel, Ute; Derntl, Birgit
2016-02-15
Social rewards are processed by the same dopaminergic-mediated brain networks as non-social rewards, suggesting a common representation of subjective value. Individual differences in personality and motivation influence the reinforcing value of social incentives, but it remains open whether the pursuit of social incentives is analogously supported by the neural reward system when positive social stimuli are connected to approach behavior. To test for a modulation of neural activation by approach motivation, individuals with high and low approach motivation (BAS) completed implicit and explicit social approach-avoidance paradigms during fMRI. High approach motivation was associated with faster implicit approach reactions as well as a trend for higher approach ratings, indicating increased approach tendencies. Implicit and explicit positive social approach was accompanied by stronger recruitment of the nucleus accumbens, middle cingulate cortex, and (pre-)cuneus for individuals with high compared to low approach motivation. These results support and extend prior research on social reward processing, self-other distinctions and affective judgments by linking approach motivation to the engagement of reward-related circuits during motivational reactions to social incentives. This interplay between motivational preferences and motivational contexts might underlie the rewarding experience during social interactions. Copyright © 2015 Elsevier Inc. All rights reserved.
-
Deep-Sea Microbes: Linking Biogeochemical Rates to -Omics Approaches
Herndl, G. J.; Sintes, E.; Bayer, B.; Bergauer, K.; Amano, C.; Hansman, R.; Garcia, J.; Reinthaler, T.
2016-02-01
Over the past decade substantial progress has been made in determining deep ocean microbial activity and resolving some of the enigmas in understanding the deep ocean carbon flux. Also, metagenomics approaches have shed light onto the dark ocean's microbes but linking -omics approaches to biogeochemical rate measurements are generally rare in microbial oceanography and even more so for the deep ocean. In this presentation, we will show by combining metagenomics, -proteomics and biogeochemical rate measurements on the bulk and single-cell level that deep-sea microbes exhibit characteristics of generalists with a large genome repertoire, versatile in utilizing substrate as revealed by metaproteomics. This is in striking contrast with the apparently rather uniform dissolved organic matter pool in the deep ocean. Combining the different -omics approaches with metabolic rate measurements, we will highlight some major inconsistencies and enigmas in our understanding of the carbon cycling and microbial food web structure in the dark ocean.
-
Yang, Hongfei; Li, Juan
2016-01-01
The present study examined the associations between linking, response to positive affect, and psychological functioning in Chinese college students. The results of conducting multiple mediation analyses indicated that emotion- and self-focused positive rumination mediated the relationship between linking and psychological functioning, whereas…
-
Using ecological production functions to link ecological processes to ecosystem services.
Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively ...
-
Single proteins that serve linked functions in intracellular and extracellular microenvironments
Energy Technology Data Exchange (ETDEWEB)
Radisky, Derek C.; Stallings-Mann, Melody; Hirai, Yohei; Bissell, Mina J.
2009-06-03
Maintenance of organ homeostasis and control of appropriate response to environmental alterations requires intimate coordination of cellular function and tissue organization. An important component of this coordination may be provided by proteins that can serve distinct, but linked, functions on both sides of the plasma membrane. Here we present a novel hypothesis in which non-classical secretion can provide a mechanism through which single proteins can integrate complex tissue functions. Single genes can exert a complex, dynamic influence through a number of different processes that act to multiply the function of the gene product(s). Alternative splicing can create many different transcripts that encode proteins of diverse, even antagonistic, function from a single gene. Posttranslational modifications can alter the stability, activity, localization, and even basic function of proteins. A protein can exist in different subcellular localizations. More recently, it has become clear that single proteins can function both inside and outside the cell. These proteins often lack defined secretory signal sequences, and transit the plasma membrane by mechanisms separate from the classical ER/Golgi secretory process. When examples of such proteins are examined individually, the multifunctionality and lack of a signal sequence are puzzling - why should a protein with a well known function in one context function in such a distinct fashion in another? We propose that one reason for a single protein to perform intracellular and extracellular roles is to coordinate organization and maintenance of a global tissue function. Here, we describe in detail three specific examples of proteins that act in this fashion, outlining their specific functions in the extracellular space and in the intracellular space, and we discuss how these functions may be linked. We present epimorphin/syntaxin-2, which may coordinate morphogenesis of secretory organs (as epimorphin) with control of
-
Engelmann, Péter; Hayashi, Yuya; Bodó, Kornélia; Ernszt, Dávid; Somogyi, Ildikó; Steib, Anita; Orbán, József; Pollák, Edit; Nyitrai, Miklós; Németh, Péter; Molnár, László
2016-12-01
Flow cytometry is a common approach to study invertebrate immune cells including earthworm coelomocytes. However, the link between light-scatter- and microscopy-based phenotyping remains obscured. Here we show, by means of light scatter-based cell sorting, both subpopulations (amoebocytes and eleocytes) can be physically isolated with good sort efficiency and purity confirmed by downstream morphological and cytochemical applications. Immunocytochemical analysis using anti-EFCC monoclonal antibodies combined with phalloidin staining has revealed antigenically distinct, sorted subsets. Screening of lectin binding capacity indicated wheat germ agglutinin (WGA) as the strongest reactor to amoebocytes. This is further evidenced by WGA inhibition assays that suggest high abundance of N-acetyl-d-glucosamine in amoebocytes. Post-sort phagocytosis assays confirmed the functional differences between amoebocytes and eleocytes, with the former being in favor of bacterial engulfment. This study has proved successful in linking flow cytometry and microscopy analysis and provides further experimental evidence of phenotypic and functional heterogeneity in earthworm coelomocyte subsets. Copyright © 2016 Elsevier Ltd. All rights reserved.
-
Linking Design to Business Strategy Through Functional Analysis
DEFF Research Database (Denmark)
Simonsen, Jesper
1997-01-01
The paper discusses how designers, conducting design projects in specific organization's, can assure that the design of IT is appropriately linked to the organizations overall business strategy. A case study is presented in the form of a design project in a small public organization. Functional...... analysis was used as a means to clarify how a specific needed information system could support the organization's new business strategy. Using functional analysis in the design project had a powerful effect: it seriously challenged the organization's business strategy and revealed that the system...... to the relation between an organization's IT-projects and its business strategy and by suggesting that it is the responsibility of the designers, conducting design projects, to assure that this task is taken proper care of. Practical guidelines for this purpose are given....
-
Energy Technology Data Exchange (ETDEWEB)
Chinthavali, Supriya [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2016-04-01
Surface transportation road networks share structural properties similar to other complex networks (e.g., social networks, information networks, biological networks, and so on). This research investigates the structural properties of road networks for any possible correlation with the traffic characteristics such as link flows those determined independently. Additionally, we define a criticality index for the links of the road network that identifies the relative importance in the network. We tested our hypotheses with two sample road networks. Results show that, correlation exists between the link flows and centrality measures of a link of the road (dual graph approach is followed) and the criticality index is found to be effective for one test network to identify the vulnerable nodes.
-
DEFF Research Database (Denmark)
Kleine-Kohlbrecher, Daniela; Christensen, Jesper; Vandamme, Julien
2010-01-01
X-linked mental retardation (XLMR) is an inherited disorder that mostly affects males and is caused by mutations in genes located on the X chromosome. Here, we show that the XLMR protein PHF8 and a C. elegans homolog F29B9.2 catalyze demethylation of di- and monomethylated lysine 9 of histone H3 (H......3K9me2/me1). The PHD domain of PHF8 binds to H3K4me3 and colocalizes with H3K4me3 at transcription initiation sites. Furthermore, PHF8 interacts with another XMLR protein, ZNF711, which binds to a subset of PHF8 target genes, including the XLMR gene JARID1C. Of interest, the C. elegans PHF8 homolog...... is highly expressed in neurons, and mutant animals show impaired locomotion. Taken together, our results functionally link the XLMR gene PHF8 to two other XLMR genes, ZNF711 and JARID1C, indicating that MR genes may be functionally linked in pathways, causing the complex phenotypes observed in patients...
-
Density functional approach for pairing in finite size systems
International Nuclear Information System (INIS)
Hupin, G.
2011-09-01
The combination of functional theory where the energy is written as a functional of the density, and the configuration mixing method, provides an efficient description of nuclear ground and excited state properties. The specific pathologies that have been recently observed, show the lack of a clear underlying justification associated to the breaking and the restoration of symmetries within density functional theory. This thesis focuses on alternative treatments of pairing correlations in finite many body systems that consider the breaking and the restoration of the particle number conservation. The energy is written as a functional of a projected quasi-particle vacuum and can be linked to the one obtained within the configuration mixing framework. This approach has been applied to make the projection either before or after the application of the variational principle. It is more flexible than the usual configuration mixing method since it can handle more general effective interactions than the latter. The application to the Krypton isotopes shows the feasibility and the efficiency of the method to describe pairing near closed shell nuclei. Following a parallel path, a theory where the energy is written as a functional of the occupation number and natural orbitals is proposed. The new functional is benchmarked in an exactly solvable model, the pairing Hamiltonian. The efficiency and the applicability of the new theory have been tested for various pairing strengths, single particle energy spectra and numbers of particles. (author)
-
Crichton, Gamal; Guo, Yufan; Pyysalo, Sampo; Korhonen, Anna
2018-05-21
Link prediction in biomedical graphs has several important applications including predicting Drug-Target Interactions (DTI), Protein-Protein Interaction (PPI) prediction and Literature-Based Discovery (LBD). It can be done using a classifier to output the probability of link formation between nodes. Recently several works have used neural networks to create node representations which allow rich inputs to neural classifiers. Preliminary works were done on this and report promising results. However they did not use realistic settings like time-slicing, evaluate performances with comprehensive metrics or explain when or why neural network methods outperform. We investigated how inputs from four node representation algorithms affect performance of a neural link predictor on random- and time-sliced biomedical graphs of real-world sizes (∼ 6 million edges) containing information relevant to DTI, PPI and LBD. We compared the performance of the neural link predictor to those of established baselines and report performance across five metrics. In random- and time-sliced experiments when the neural network methods were able to learn good node representations and there was a negligible amount of disconnected nodes, those approaches outperformed the baselines. In the smallest graph (∼ 15,000 edges) and in larger graphs with approximately 14% disconnected nodes, baselines such as Common Neighbours proved a justifiable choice for link prediction. At low recall levels (∼ 0.3) the approaches were mostly equal, but at higher recall levels across all nodes and average performance at individual nodes, neural network approaches were superior. Analysis showed that neural network methods performed well on links between nodes with no previous common neighbours; potentially the most interesting links. Additionally, while neural network methods benefit from large amounts of data, they require considerable amounts of computational resources to utilise them. Our results indicate
-
Canary, Jana D; Blizzard, Leigh; Barry, Ronald P; Hosmer, David W; Quinn, Stephen J
2016-05-01
Generalized linear models (GLM) with a canonical logit link function are the primary modeling technique used to relate a binary outcome to predictor variables. However, noncanonical links can offer more flexibility, producing convenient analytical quantities (e.g., probit GLMs in toxicology) and desired measures of effect (e.g., relative risk from log GLMs). Many summary goodness-of-fit (GOF) statistics exist for logistic GLM. Their properties make the development of GOF statistics relatively straightforward, but it can be more difficult under noncanonical links. Although GOF tests for logistic GLM with continuous covariates (GLMCC) have been applied to GLMCCs with log links, we know of no GOF tests in the literature specifically developed for GLMCCs that can be applied regardless of link function chosen. We generalize the Tsiatis GOF statistic originally developed for logistic GLMCCs, (TG), so that it can be applied under any link function. Further, we show that the algebraically related Hosmer-Lemeshow (HL) and Pigeon-Heyse (J(2) ) statistics can be applied directly. In a simulation study, TG, HL, and J(2) were used to evaluate the fit of probit, log-log, complementary log-log, and log models, all calculated with a common grouping method. The TG statistic consistently maintained Type I error rates, while those of HL and J(2) were often lower than expected if terms with little influence were included. Generally, the statistics had similar power to detect an incorrect model. An exception occurred when a log GLMCC was incorrectly fit to data generated from a logistic GLMCC. In this case, TG had more power than HL or J(2) . © 2015 John Wiley & Sons Ltd/London School of Economics.
-
Bodzin, Alec; Anastasio, David; Sahagian, Dork; Henry, Jill Burrows
2016-01-01
A curriculum-linked professional development approach designed to support middle level science teachers' understandings about tectonics and geospatial pedagogical content knowledge was developed. This approach takes into account limited face-to-face professional development time and instead provides pedagogical support within the design of a…
-
DEFF Research Database (Denmark)
Wistoft, Karen; Højlund, Holger
2012-01-01
educational goals, learning content, or value clarification. Health pedagogy is often a matter of retrospective rationalization rather than the starting point of planning. Health and risk behaviour approaches override health educational approaches. Conclusions: Operational links between health education......, health professionalism, and management strategies pose the foremost challenge. Operational links indicates cooperative levels that facilitate a creative and innovative effort across traditional professional boundaries. It is proposed that such links are supported by network structures, shared semantics...
-
Light-induced cross-linking and post-cross-linking modification of polyglycidol.
Marquardt, F; Bruns, M; Keul, H; Yagci, Y; Möller, M
2018-02-08
The photoinduced radical generation process has received renewed interest due to its economic and ecological appeal. Herein the light-induced cross-linking of functional polyglycidol and its post-cross-linking modification are presented. Linear polyglycidol was first functionalized with a tertiary amine in a two-step reaction. Dimethylaminopropyl functional polyglycidol was cross-linked in a UV-light mediated reaction with camphorquinone as a type II photoinitiator. The cross-linked polyglycidol was further functionalized by quaternization with various organoiodine compounds. Aqueous dispersions of the cross-linked polymers were investigated by means of DLS and zeta potential measurements. Polymer films were evaluated by DSC and XPS.
-
Directory of Open Access Journals (Sweden)
Santosh Kumar Nanda
2011-01-01
Full Text Available Functional link-based neural network models were applied to predict opencast mining machineries noise. The paper analyzes the prediction capabilities of functional link neural network based noise prediction models vis-à-vis existing statistical models. In order to find the actual noise status in opencast mines, some of the popular noise prediction models, for example, ISO-9613-2, CONCAWE, VDI, and ENM, have been applied in mining and allied industries to predict the machineries noise by considering various attenuation factors. Functional link artificial neural network (FLANN, polynomial perceptron network (PPN, and Legendre neural network (LeNN were used to predict the machinery noise in opencast mines. The case study is based on data collected from an opencast coal mine of Orissa, India. From the present investigations, it could be concluded that the FLANN model give better noise prediction than the PPN and LeNN model.
-
Roberts, James S.; Bao, Han; Huang, Chun-Wei; Gagne, Phill
Characteristic curve approaches for linking parameters from the generalized partial credit model were examined for cases in which common (anchor) items are calibrated separately in two groups. Three of these approaches are simple extensions of the test characteristic curve (TCC), item characteristic curve (ICC), and operating characteristic curve…
-
Capmany, J; Gasulla, Ivana
2007-08-20
Although a considerable number of multimode fiber (MMF) links operate in a wavelength region around 850 nm where chromatic dispersion of a given modal group mu is described adequately by the second derivative beta(mu) (2) of the propagation constant beta(mu)(omega), there is also an increasing interest in MMF links transmitting in the second spectral window (@1300nm) where this second derivative vanishes being thus necessary to consider the third derivative beta(mu) (3) in the evaluation of the transfer function of the multimode fiber link. We present in this paper, for the first time to our knowledge, an analytical model for the transfer function of a multimode fiber (MMF) optic link taken into account the impact of third-order dispersion. The model extends the operation of a previously reported one for second-order dispersion. Our results show that the performance of broadband radio over fiber transmission through middle-reach distances can be improved by working at the minimum-dispersion wavelength as long as low-linewidth lasers are employed.
-
Rütten, Alfred; Gelius, Peter
2014-09-01
This article outlines a theoretical framework for an interactive, research-driven approach to building policy capacities in health promotion. First, it illustrates how two important issues in the recent public health debate, capacity building and linking scientific knowledge to policy action, are connected to each other theoretically. It then introduces an international study on an interactive approach to capacity building in health promotion policy. The approach combines the ADEPT model of policy capacities with a co-operative planning process to foster the exchange of knowledge between policy-makers and researchers, thus improving intra- and inter-organizational capacities. A regional-level physical activity promotion project involving governmental and public-law institutions, NGOs and university researchers serves as a case study to illustrate the potential of the approach for capacity building. Analysis and comparison with a similar local-level project indicate that the approach provides an effective means of linking scientific knowledge to policy action and to planning concrete measures for capacity building in health promotion, but that it requires sufficiently long timelines and adequate resources to achieve adequate implementation and sustainability. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
-
The Effect of Error in Item Parameter Estimates on the Test Response Function Method of Linking.
Kaskowitz, Gary S.; De Ayala, R. J.
2001-01-01
Studied the effect of item parameter estimation for computation of linking coefficients for the test response function (TRF) linking/equating method. Simulation results showed that linking was more accurate when there was less error in the parameter estimates, and that 15 or 25 common items provided better results than 5 common items under both…
-
Quantum functional analysis non-coordinate approach
Helemskii, A Ya
2010-01-01
This book contains a systematic presentation of quantum functional analysis, a mathematical subject also known as operator space theory. Created in the 1980s, it nowadays is one of the most prominent areas of functional analysis, both as a field of active research and as a source of numerous important applications. The approach taken in this book differs significantly from the standard approach used in studying operator space theory. Instead of viewing "quantized coefficients" as matrices in a fixed basis, in this book they are interpreted as finite rank operators in a fixed Hilbert space. This allows the author to replace matrix computations with algebraic techniques of module theory and tensor products, thus achieving a more invariant approach to the subject. The book can be used by graduate students and research mathematicians interested in functional analysis and related areas of mathematics and mathematical physics. Prerequisites include standard courses in abstract algebra and functional analysis.
-
AN INTEGRATED APPROACH FOR LINKED DATA BROWSING
Directory of Open Access Journals (Sweden)
W. Beek
2017-07-01
Full Text Available The Netherlands' Cadastre, Land Registry and Mapping Agency – in short Kadaster – collects and registers administrative and spatial data on property and the rights involved. Currently, the Kadaster is publishing its geo-spatial data assets as Linked Open Data. The Kadaster manages hundreds of datasets that describe hundreds of millions of geospatial objects, including all Dutch buildings, roads, and forests. The Kadaster exposes this large collection of data to thousands of daily users that operate from within different contexts and that need to be supported in different use cases. Therefore, Kadaster must offer diverse, yet complementary, approaches for browsing and exploring the data it publishes. Specifically, it supports the following paradigms for browsing and exploring its data assets: hierarchical browsing, graph navigation, faceted browsing, and tabular browsing. These paradigms are useful for different tasks, cover different use cases, and are implemented by reusing and/or developing Open Source libraries and applications.
-
Functional Role of N-Linked Glycosylation in Pseudorabies Virus Glycoprotein gH.
Vallbracht, Melina; Rehwaldt, Sascha; Klupp, Barbara G; Mettenleiter, Thomas C; Fuchs, Walter
2018-05-01
Many viral envelope proteins are modified by asparagine (N)-linked glycosylation, which can influence their structure, physicochemical properties, intracellular transport, and function. Here, we systematically analyzed the functional relevance of N-linked glycans in the alphaherpesvirus pseudorabies virus (PrV) glycoprotein H (gH), which is an essential component of the conserved core herpesvirus fusion machinery. Upon gD-mediated receptor binding, the heterodimeric complex of gH and gL activates gB to mediate fusion of the viral envelope with the host cell membrane for viral entry. gH contains five potential N-linked glycosylation sites at positions 77, 162, 542, 604, and 627, which were inactivated by conservative mutations (asparagine to glutamine) singly or in combination. The mutated proteins were tested for correct expression and fusion activity. Additionally, the mutated gH genes were inserted into the PrV genome for analysis of function during virus infection. Our results demonstrate that all five sites are glycosylated. Inactivation of the PrV-specific N77 or the conserved N627 resulted in significantly reduced in vitro fusion activity, delayed penetration kinetics, and smaller virus plaques. Moreover, substitution of N627 greatly affected transport of gH in transfected cells, resulting in endoplasmic reticulum (ER) retention and reduced surface expression. In contrast, mutation of N604, which is conserved in the Varicellovirus genus, resulted in enhanced in vitro fusion activity and viral cell-to-cell spread. These results demonstrate a role of the N-glycans in proper localization and function of PrV gH. However, even simultaneous inactivation of all five N-glycosylation sites of gH did not severely inhibit formation of infectious virus particles. IMPORTANCE Herpesvirus infection requires fusion of the viral envelope with cellular membranes, which involves the conserved fusion machinery consisting of gB and the heterodimeric gH/gL complex. The bona fide
-
Armitage, David W
2017-11-01
Ecosystem development theory predicts that successional turnover in community composition can influence ecosystem functioning. However, tests of this theory in natural systems are made difficult by a lack of replicable and tractable model systems. Using the microbial digestive associates of a carnivorous pitcher plant, I tested hypotheses linking host age-driven microbial community development to host functioning. Monitoring the yearlong development of independent microbial digestive communities in two pitcher plant populations revealed a number of trends in community succession matching theoretical predictions. These included mid-successional peaks in bacterial diversity and metabolic substrate use, predictable and parallel successional trajectories among microbial communities, and convergence giving way to divergence in community composition and carbon substrate use. Bacterial composition, biomass, and diversity positively influenced the rate of prey decomposition, which was in turn positively associated with a host leaf's nitrogen uptake efficiency. Overall digestive performance was greatest during late summer. These results highlight links between community succession and ecosystem functioning and extend succession theory to host-associated microbial communities.
-
Multiscale approach to link red blood cell dynamics, shear viscosity, and ATP release.
Forsyth, Alison M; Wan, Jiandi; Owrutsky, Philip D; Abkarian, Manouk; Stone, Howard A
2011-07-05
RBCs are known to release ATP, which acts as a signaling molecule to cause dilation of blood vessels. A reduction in the release of ATP from RBCs has been linked to diseases such as type II diabetes and cystic fibrosis. Furthermore, reduced deformation of RBCs has been correlated with myocardial infarction and coronary heart disease. Because ATP release has been linked to cell deformation, we undertook a multiscale approach to understand the links between single RBC dynamics, ATP release, and macroscopic viscosity all at physiological shear rates. Our experimental approach included microfluidics, ATP measurements using a bioluminescent reaction, and rheology. Using microfluidics technology with high-speed imaging, we visualize the deformation and dynamics of single cells, which are known to undergo motions such as tumbling, swinging, tanktreading, and deformation. We report that shear thinning is not due to cellular deformation as previously believed, but rather it is due to the tumbling-to-tanktreading transition. In addition, our results indicate that ATP release is constant at shear stresses below a threshold (3 Pa), whereas above the threshold ATP release is increased and accompanied by large cellular deformations. Finally, performing experiments with well-known inhibitors, we show that the Pannexin 1 hemichannel is the main avenue for ATP release both above and below the threshold, whereas, the cystic fibrosis transmembrane conductance regulator only contributes to deformation-dependent ATP release above the stress threshold.
-
Directory of Open Access Journals (Sweden)
Wenqiong eXue
2015-02-01
Full Text Available Recent innovations in neuroimaging technology have provided opportunities for researchers to investigate connectivity in the human brain by examining the anatomical circuitry as well as functional relationships between brain regions. Existing statistical approaches for connectivity generally examine resting-state or task-related functional connectivity (FC between brain regions or separately examine structural linkages. As a means to determine brain networks, we present a unified Bayesian framework for analyzing FC utilizing the knowledge of associated structural connections, which extends an approach by Patel et al.(2006a that considers only functional data. We introduce an FC measure that rests upon assessments of functional coherence between regional brain activity identified from functional magnetic resonance imaging (fMRI data. Our structural connectivity (SC information is drawn from diffusion tensor imaging (DTI data, which is used to quantify probabilities of SC between brain regions. We formulate a prior distribution for FC that depends upon the probability of SC between brain regions, with this dependence adhering to structural-functional links revealed by our fMRI and DTI data. We further characterize the functional hierarchy of functionally connected brain regions by defining an ascendancy measure that compares the marginal probabilities of elevated activity between regions. In addition, we describe topological properties of the network, which is composed of connected region pairs, by performing graph theoretic analyses. We demonstrate the use of our Bayesian model using fMRI and DTI data from a study of auditory processing. We further illustrate the advantages of our method by comparisons to methods that only incorporate functional information.
-
Habashi, Meara M; Graziano, William G; Hoover, Ann E
2016-09-01
The search for the prosocial personality has been long and controversial. The current research explores the general patterns underlying prosocial decisions, linking personality, emotion, and overt prosocial behavior. Using a multimethod approach, we explored the links between the Big Five dimensions of personality and prosocial responding. Across three studies, we found that agreeableness was the dimension of personality most closely associated with emotional reactions to victims in need of help, and subsequent decisions to help those individuals. Results suggest that prosocial processes, including emotions, cognitions, and behaviors, may be part of a more general motivational process linked to personality. © 2016 by the Society for Personality and Social Psychology, Inc.
-
Linking biomedical engineering ethics case study approach and policy.
Dibrell, William; Dobie, Elizabeth Ann
2007-01-01
In this paper we link bioengineering case study methods to the development of policy. The case study approach to ethics is an excellent way to show the complex nature of practical/moral reasoning. This approach can, however, lead to a kind of overwhelming complexity. The individual nature of each case makes it difficult to identify the most important information and difficult to see what moral considerations are most relevant. In order to make the overwhelming complexity less debilitating, we present a framework for moral decision making derived from suggestions made by W.D. Ross and Virginia Held. Ross articulates the multiple sources of morality and Held deepens the discussion by reminding us of the foundational importance of care and sympathy to our moral natures. We show how to use the notion of prima facie duty and discuss moral conflict. In doing this, we show how the framework, applied to cases, can be of assistance in helping us develop policies and codes of ethics with sufficient plasticity to be useful in the complex world of the bioengineer.
-
Geochip: A high throughput genomic tool for linking community structure to functions
Energy Technology Data Exchange (ETDEWEB)
Van Nostrand, Joy D.; Liang, Yuting; He, Zhili; Li, Guanghe; Zhou, Jizhong
2009-01-30
GeoChip is a comprehensive functional gene array that targets key functional genes involved in the geochemical cycling of N, C, and P, sulfate reduction, metal resistance and reduction, and contaminant degradation. Studies have shown the GeoChip to be a sensitive, specific, and high-throughput tool for microbial community analysis that has the power to link geochemical processes with microbial community structure. However, several challenges remain regarding the development and applications of microarrays for microbial community analysis.
-
An Integrated Approach for Reliable Facility Location/Network Design Problem with Link Disruption
Directory of Open Access Journals (Sweden)
Davood Shishebori
2015-05-01
Full Text Available Proposing a robust designed facility location is one of the most effective ways to hedge against unexpected disruptions and failures in a transportation network system. This paper considers the combined facility location/network design problem with regard to transportation link disruptions and develops a mixed integer linear programming formulation to model it. With respect to the probability of link disruptions, the objective function of the model minimizes the total costs, including location costs, link construction costs and also the expected transportation costs. An efficient hybrid algorithm based on LP relaxation and variable neighbourhood search metaheuristic is developed in order to solve the mathematical model. Numerical results demonstrate that the proposed hybrid algorithm has suitable efficiency in terms of duration of solution time and determining excellent solution quality.
-
CRISPR/Cas9 Promotes Functional Study of Testis Specific X-Linked Gene In Vivo.
Directory of Open Access Journals (Sweden)
Minyan Li
Full Text Available Mammalian spermatogenesis is a highly regulated multistage process of sperm generation. It is hard to uncover the real function of a testis specific gene in vitro since the in vitro model is not yet mature. With the development of the CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated 9 system, we can now rapidly generate knockout mouse models of testis specific genes to study the process of spermatogenesis in vivo. SYCP3-like X-linked 2 (SLX2 is a germ cell specific component, which contains a Cor1 domain and belongs to the XLR (X-linked, lymphocyte regulated family. Previous studies suggested that SLX2 might play an important role in mouse spermatogenesis based on its subcellular localization and interacting proteins. However, the function of SLX2 in vivo is still elusive. Here, to investigate the functions of SLX2 in spermatogenesis, we disrupted the Slx2 gene by using the CRISPR/Cas9 system. Since Slx2 is a testis specific X-linked gene, we obtained knockout male mice in the first generation and accelerated the study process. Compared with wild-type mice, Slx2 knockout mice have normal testis and epididymis. Histological observation of testes sections showed that Slx2 knockout affected none of the three main stages of spermatogenesis: mitosis, meiosis and spermiogenesis. In addition, we further confirmed that disruption of Slx2 did not affect the number of spermatogonial stem cells, meiosis progression or XY body formation by immunofluorescence analysis. As spermatogenesis was normal in Slx2 knockout mice, these mice were fertile. Taken together, we showed that Slx2 itself is not an essential gene for mouse spermatogenesis and CRISPR/Cas9 technique could speed up the functional study of testis specific X-linked gene in vivo.
-
An inverse approach for elucidating dendritic function
Directory of Open Access Journals (Sweden)
Benjamin Torben-Nielsen
2010-09-01
Full Text Available We outline an inverse approach for investigating dendritic function-structure relationships by optimizing dendritic trees for a-priori chosen computational functions. The inverse approach can be applied in two different ways. First, we can use it as a `hypothesis generator' in which we optimize dendrites for a function of general interest. The optimization yields an artificial dendrite that is subsequently compared to real neurons. This comparison potentially allows us to propose hypotheses about the function of real neurons. In this way, we investigated dendrites that optimally perform input-order detection. Second, we can use it as a `function confirmation' by optimizing dendrites for functions hypothesized to be performed by classes of neurons. If the optimized, artificial, dendrites resemble the dendrites of real neurons the artificial dendrites corroborate the hypothesized function of the real neuron. Moreover, properties of the artificial dendrites can lead to predictions about yet unmeasured properties. In this way, we investigated wide-field motion integration performed by the VS cells of the fly visual system. In outlining the inverse approach and two applications, we also elaborate on the nature of dendritic function. We furthermore discuss the role of optimality in assigning functions to dendrites and point out interesting future directions.
-
Markova, Iu M; Sheveleva, S A
2014-01-01
This review concerns the issues of foodfortifications and the creation of functional foods (FF) and food supplements based on probiotics and covers an issue of approaches to the regulation of probiotic food products in various countries. The status of functional foods, optimizing GIT functions, as a separate category of FF is emphasized. Considering the strain-specificity effect of probiotics, the minimum criteria used for probiotics in food products are: 1) the need to identify a probiotics at genus, species, and strain levels, using the high-resolution techniques, 2) the viability and the presence of a sufficient amount of the probiotic in product at the end of shelf life, 3) the proof of functional characteristics inherent to probiotic strains, in the controlled experiments. The recommended by FA O/WHO three-stage evaluation procedure offunctional efficiency of FF includes: Phase I--safety assessment in in vitro and in vivo experiments, Phase II--Evaluation in the Double-Blind, Randomized, Placebo-Controlled trial (DBRPC) and Phase III--Post-approval monitoring. It is noted that along with the ability to obtain statistically significant results of the evaluation, there are practical difficulties of conducting DBRPC (duration, costs, difficulties in selection of target biomarkers and populations). The promising approach for assessing the functional efficacy of FF is the concept of nutrigenomics. It examines the link between the human diet and the characteristics of his genome to determine the influence of food on the expression of genes and, ultimately, to human health. Nutrigenomic approaches are promising to assess the impact of probiotics in healthy people. The focusing on the nutrigenomic response of intestinal microbial community and its individual populations (in this regard the lactobacilli can be very informative) was proposed.
-
Systemic-Functional Approach to Utilities Supplys
Directory of Open Access Journals (Sweden)
Nikolay I. Komkov
2017-01-01
Full Text Available Purpose: the purpose of the article consists in statement of management approach to development of utilities supply processes based on conflict situations decision – making search. It had appeared in the period of the transition from the planned and directive management to market development. Methods: the research methodology is based on the system analysis of full life cycle processes functioning, forecasting of complex systems development, mathematical modeling of processes of services supply and innovative and investment projects modeling as well as development of supplying services processes. Results: the results of the work are concentrated in the presentation of systemic-functional approach to managing the development of processes of municipal services, able to resolve conflict situations in this sphere. Conclusions and Relevance: the traditional management approach on the basis of elimination of "bottlenecks" and emergencies prevailing within planned and directive system at its transformation in the market conditions has led to accumulation of conflict situations and unsolvable problems. The offered systemic-functional approach based on forecasting of full life cycle of the modernized processes and the services providing systems allows to consider costs of modernization, prime cost and quality of the rendered services.
-
Non-dipolar gauge links for transverse-momentum-dependent pion wave functions
International Nuclear Information System (INIS)
Wang, Y.M.
2016-01-01
I discuss the factorization-compatible definitions of transverse-momentum-dependent (TMD) pion wave functions which are fundamental theory inputs entering QCD factorization formulae for many hard exclusive processes. I will first demonstrate that the soft subtraction factor introduced to remove both rapidity and pinch singularities can be greatly reduced by making the maximal use of the freedom to construct the Wilson-line paths when defining the TMD wave functions. I will then turn to show that the newly proposed TMD definition with non-dipolar Wilson lines is equivalent to the one with dipolar gauge links and with a complicated soft function, to all orders of the perturbative expansion in the strong coupling, as far as the infrared behavior is concerned. (author)
-
A Functional Approach to User Guides
DEFF Research Database (Denmark)
Nielsen, Sandro
2007-01-01
to fulfil the requirements of users. By applying the functional approach lexicographers are forced to reconsider the scope of the user guide. The user guide has traditionally centred on the structures of entries - and consequently on the word list - but its scope should be widened, so as to include all......The functional approach opens up exciting new possibilities for theoretical and practical lexicography. It encourages lexicographers to adopt a new way of thinking when planning and compiling dictionaries and when discussing and developing new lexicographic principles. One area in which it impacts...... on lexicography and lexicographic products is the writing of a really crafted and valuable user guide for instance by giving increased consideration to the user perspective. This involves the identification of the functions of the dictionary in terms of communication-oriented and cognitive functions, which helps...
-
Vadakkan, Kunjumon I.
2011-01-01
The internal sensation of memory, which is available only to the owner of an individual nervous system, is difficult to analyze for its basic elements of operation. We hypothesize that associative learning induces the formation of functional LINK between the postsynapses. During memory retrieval, the activation of either postsynapse re-activates the functional LINK evoking a semblance of sensory activity arriving at its opposite postsynapse, nature of which defines the basic unit of internal sensation – namely, the semblion. In neuronal networks that undergo continuous oscillatory activity at certain levels of their organization re-activation of functional LINKs is expected to induce semblions, enabling the system to continuously learn, self-organize, and demonstrate instantiation, features that can be utilized for developing artificial intelligence (AI). This paper also explains suitability of the inter-postsynaptic functional LINKs to meet the expectations of Minsky’s K-lines, basic elements of a memory theory generated to develop AI and methods to replicate semblances outside the nervous system. PMID:21845180
-
Ramakrishna, Ramnarain; Sarkar, Dipayan; Manduri, Avani; Iyer, Shreyas Ganesan; Shetty, Kalidas
2017-10-01
Sprouts of cereal grains, such as barley ( Hordeum vulgare L.), are a good source of beneficial phenolic bioactives. Such health relevant phenolic bioactives of cereal sprouts can be targeted to manage chronic hyperglycemia and oxidative stress commonly associated with type 2 diabetes (T2D). Therefore improving phenolic bioactives by stimulating plant endogenous defense responses such as protective pentose phosphate pathway (PPP) during sprouting has significant merit. Based on this metabolic rationale, this study aimed to enhance phenolic bioactives and associated antioxidant and anti-hyperglycemic functions in dark germinated barley sprouts using exogenous elicitor treatments. Dark-germinated sprouts of two malting barley cultivars (Pinnacle and Celebration), treated with chitosan oligosaccharide (COS) and marine protein hydrolysate (GP), were evaluated. Total soluble phenolic content (TSP), phenolic acid profiles, total antioxidant activity (TA) and in vitro inhibitory activities of hyperglycemia relevant α-amylase and α-glucosidase enzymes of the dark germinated barley sprouts were evaluated at day 2, 4, and 6 post elicitor treatments. Overall, TSP content, TA, and α-amylase inhibitory activity of dark germinated barley sprouts decreased, while α-glucosidase inhibitory activity and gallic acid content increased from day 2 to day 6. Among barley cultivars, high phenolic antioxidant-linked anti-hyperglycemic bioactives were observed in Celebration. Furthermore, GP and COS seed elicitor treatments in selective doses improved T2D relevant phenolic-linked anti-hyperglycemic bioactives of barley spouts at day 6. Therefore, such seed elicitation approach can be strategically used to develop bioactive enriched functional food ingredients from cereal sprouts targeting chronic hyperglycemia and oxidative stress linked to T2D.
-
Approach to assess consequences of hypoxia disturbance events for benthic ecosystem functioning
Gogina, Mayya; Darr, Alexander; Zettler, Michael L.
2014-01-01
Our study challenges the functional approach for its usefulness in assessing the consequences of hypoxia disturbance events on macrofaunal communities in the south-western Baltic Sea. Time series for two decades of observations from two monitoring stations, one in the Fehmarnbelt (exposed to aperiodic hypoxia), and another in the Darss Rise (normoxic conditions) is used. Our results designate differences of functional structure of benthic fauna communities between sites based on biological traits that characterise species role in modifying the environment, behavioural strategies, morphology and life history, thus suggesting differences in functioning. Hypoxic years reveal sharp increase of the role of sedentary species, suspension filter feeders, epibenthic structures, globulose form, medium/large size of individuals, preponderance of species with long lifespan (caused for instance by remaining ocean quahog). The link of functional and species diversity to the stagnation periods is proposed for the Darss station that exhibit continuous changes and low temporal variability of traits distribution. Before the major inflow in 1993 the increased role of small size organisms, containing calcium carbonate, filter feeders and grazers, higher presence of semi-pelagic species is observed. The hypoxic events and water renewal processes impact the communities not only in respect to species composition but also functionally.
-
Lee, Min Kyung; Baker, Sara; Whitebread, David
2018-06-01
Research on the relationships between parental factors and children's executive function (EF) has been conducted mainly in Western cultures. This study provides the first empirical test, in a non-Western context, of how maternal EF and parenting behaviours relate to child EF. South Korean mothers and their preschool children (N = 95 dyads) completed EF tasks. Two aspects of parental scaffolding were observed during a puzzle task: contingency (i.e., adjusting among levels of scaffolding according to the child's ongoing evidence of understanding) and intrusiveness (i.e., directive, mother-centred interactions). Maternal EF and maternal contingency each accounted for unique variance in child EF, above and beyond child age, child language and maternal education. Maternal intrusiveness, however, was not significantly related to child EF. Additionally, no mediating role of parenting was found in the maternal and child EF link. However, child language was found to partially mediate the link between maternal contingency and child EF. These results complement prior findings by revealing distinctive patterns in the link between maternal EF, parenting behaviours, and child EF in the Korean context. © 2018 The British Psychological Society.
-
Using ecological production functions to link ecological ...
Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively little attention. Ecological production functions may be defined as usable expressions (i.e., models) of the processes by which ecosystems produce ES, often including external influences on those processes. We identify key attributes of EPFs and discuss both actual and idealized examples of their use to inform decision making. Whenever possible, EPFs should estimate final, rather than intermediate, ES. Although various types of EPFs have been developed, we suggest that EPFs are more useful for decision making if they quantify ES outcomes, respond to ecosystem condition, respond to stressor levels or management scenarios, reflect ecological complexity, rely on data with broad coverage, have performed well previously, are practical to use, and are open and transparent. In an example using pesticides, we illustrate how EPFs with these attributes could enable the inclusion of ES in ecological risk assessment. The biggest challenges to ES inclusion are limited data sets that are easily adapted for use in modeling EPFs and generally poor understanding of linkages among ecological components and the processes that ultimately deliver the ES. We conclude by advocating for the incorporation into E
-
Use of integrin-linked kinase to extend function of encapsulated pancreatic tissue
International Nuclear Information System (INIS)
Blanchette, James O; Langer, Steven J; Leinwand, Leslie L; Sahai, Suchit; Topiwala, Pritesh S; Anseth, Kristi S
2010-01-01
We have studied the impact of overexpression of an intracellular signaling protein, integrin-linked kinase (ILK), on the survival and function of encapsulated islet tissue used for the treatment of type 1 diabetes. The dimensions of the encapsulated tissue can impact the stresses placed on the tissue and ILK overexpression shows the ability to extend function of dissociated cells as well as intact islets. These results suggest that lost cell-extracellular matrix interactions in cell encapsulation systems can lead to decreased insulin secretion and ILK signaling is a target to overcome this phenomenon. (communication)
-
Use of integrin-linked kinase to extend function of encapsulated pancreatic tissue
Energy Technology Data Exchange (ETDEWEB)
Blanchette, James O [Department of Chemical Engineering, University of South Carolina, Columbia, SC (United States); Langer, Steven J; Leinwand, Leslie L [Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO (United States); Sahai, Suchit; Topiwala, Pritesh S [Biomedical Engineering Program, University of South Carolina, Columbia, SC (United States); Anseth, Kristi S, E-mail: blanchej@cec.sc.ed [Howard Hughes Medical Institute, Boulder, CO (United States)
2010-12-15
We have studied the impact of overexpression of an intracellular signaling protein, integrin-linked kinase (ILK), on the survival and function of encapsulated islet tissue used for the treatment of type 1 diabetes. The dimensions of the encapsulated tissue can impact the stresses placed on the tissue and ILK overexpression shows the ability to extend function of dissociated cells as well as intact islets. These results suggest that lost cell-extracellular matrix interactions in cell encapsulation systems can lead to decreased insulin secretion and ILK signaling is a target to overcome this phenomenon. (communication)
-
Different perspectives on the sex-attachment link: towards an emotion-motivational account.
Dewitte, Marieke
2012-01-01
Although the link between sex and attachment was made decades ago (Hazan & Shaver, 1987), theories on sexual and attachment functioning have been developed in relative isolation. Recent efforts to integrate both literatures have been complicated by the fact that the sex-attachment link has been approached from very different perspectives, including biological, evolutionary, developmental, cognitive, and social psychology approaches. Also, at the empirical level, research on sex and attachment lacks overarching synthesis. This article gives an overview of the most important theoretical ideas and empirical insights on sex and attachment. It starts with describing general models that approach the sex-attachment link from an evolutionary and neurobiological perspective. Then, it summarizes theoretical and empirical ideas of attachment theory and describes how attachment style differences are manifested in intimate and sexual relationships. Research so far has been limited to studying the predicted link between sex and attachment in terms of broad descriptives, and it would benefit the literature to specify the processes and pathways that mediate the sex-attachment link. After a short discussion of the functional similarities between the sexual and the attachment systems, the article describes some specific--dynamical--models that focus on the emotional and cognitive-motivational processes through which attachment schemas influence sexual experiences. Such an emotion-motivational perspective on sex and attachment can help to organize theoretical ideas and empirical findings and eventually promote an integrative view on how attachment dynamics can interact with sexual experiences.
-
Raskin, Glenn; Lebby, Michael S.; Carney, F.; Kazakia, M.; Schwartz, Daniel B.; Gaw, Craig A.
1997-04-01
The OPTOBUSTM family of products provides for high performance parallel interconnection utilizing optical links in a 10-bit wide bi-directional configuration. The link is architected to be 'transparent' in that it is totally asynchronous and dc coupled so that it can be treated as a perfect cable with extremely low skew and no losses. An optical link consists of two identical transceiver modules and a pair of connectorized 62.5 micrometer multi mode fiber ribbon cables. The OPTOBUSTM I link provides bi- directional functionality at 4 Gbps (400 Mbps per channel), while the OPTOBUSTM II link will offer the same capability at 8 Gbps (800 Mbps per channel). The transparent structure of the OPTOBUSTM links allow for an arbitrary data stream regardless of its structure. Both the OPTOBUSTM I and OPTOBUSTM II transceiver modules are packaged as partially populated 14 by 14 pin grid arrays (PGA) with optical receptacles on one side of the module. The modules themselves are composed of several elements; including passives, integrated circuits optoelectronic devices and optical interface units (OIUs) (which consist of polymer waveguides and a specially designed lead frame). The initial offering of the modules electrical interface utilizes differential CML. The CML line driver sinks 5 mA of current into one of two pins. When terminated with 50 ohm pull-up resistors tied to a voltage between VCC and VCC-2, the result is a differential swing of plus or minus 250 mV, capable of driving standard PECL I/Os. Future offerings of the OPTOBUSTM links will incorporate LVDS and PECL interfaces as well as CML. The integrated circuits are silicon based. For OPTOBUSTM I links, a 1.5 micrometer drawn emitter NPN bipolar process is used for the receiver and an enhanced 0.8 micrometer CMOS process for the laser driver. For OPTOBUSTM II links, a 0.8 micrometer drawn emitter NPN bipolar process is used for the receiver and the driver IC utilizes 0.8 micrometer BiCMOS technology. The OPTOBUSTM
-
A statistical mechanical approach to restricted integer partition functions
Zhou, Chi-Chun; Dai, Wu-Sheng
2018-05-01
The main aim of this paper is twofold: (1) suggesting a statistical mechanical approach to the calculation of the generating function of restricted integer partition functions which count the number of partitions—a way of writing an integer as a sum of other integers under certain restrictions. In this approach, the generating function of restricted integer partition functions is constructed from the canonical partition functions of various quantum gases. (2) Introducing a new type of restricted integer partition functions corresponding to general statistics which is a generalization of Gentile statistics in statistical mechanics; many kinds of restricted integer partition functions are special cases of this restricted integer partition function. Moreover, with statistical mechanics as a bridge, we reveal a mathematical fact: the generating function of restricted integer partition function is just the symmetric function which is a class of functions being invariant under the action of permutation groups. Using this approach, we provide some expressions of restricted integer partition functions as examples.
-
Estimating Function Approaches for Spatial Point Processes
Deng, Chong
Spatial point pattern data consist of locations of events that are often of interest in biological and ecological studies. Such data are commonly viewed as a realization from a stochastic process called spatial point process. To fit a parametric spatial point process model to such data, likelihood-based methods have been widely studied. However, while maximum likelihood estimation is often too computationally intensive for Cox and cluster processes, pairwise likelihood methods such as composite likelihood, Palm likelihood usually suffer from the loss of information due to the ignorance of correlation among pairs. For many types of correlated data other than spatial point processes, when likelihood-based approaches are not desirable, estimating functions have been widely used for model fitting. In this dissertation, we explore the estimating function approaches for fitting spatial point process models. These approaches, which are based on the asymptotic optimal estimating function theories, can be used to incorporate the correlation among data and yield more efficient estimators. We conducted a series of studies to demonstrate that these estmating function approaches are good alternatives to balance the trade-off between computation complexity and estimating efficiency. First, we propose a new estimating procedure that improves the efficiency of pairwise composite likelihood method in estimating clustering parameters. Our approach combines estimating functions derived from pairwise composite likeli-hood estimation and estimating functions that account for correlations among the pairwise contributions. Our method can be used to fit a variety of parametric spatial point process models and can yield more efficient estimators for the clustering parameters than pairwise composite likelihood estimation. We demonstrate its efficacy through a simulation study and an application to the longleaf pine data. Second, we further explore the quasi-likelihood approach on fitting
-
Dhayal, S.K.
2015-01-01
Abstract
The aim of this thesis is to understand the connection between molecular, meso and macroscales of enzymatically cross-linked proteins. It was hypothesised that the techno-functional properties at macroscale, such as bulk rheology and foam stability, are affected
-
Linking density functional and mode coupling models for supercooled liquids.
Premkumar, Leishangthem; Bidhoodi, Neeta; Das, Shankar P
2016-03-28
We compare predictions from two familiar models of the metastable supercooled liquid, respectively, constructed with thermodynamic and dynamic approaches. In the so called density functional theory the free energy F[ρ] of the liquid is a functional of the inhomogeneous density ρ(r). The metastable state is identified as a local minimum of F[ρ]. The sharp density profile characterizing ρ(r) is identified as a single particle oscillator, whose frequency is obtained from the parameters of the optimum density function. On the other hand, a dynamic approach to supercooled liquids is taken in the mode coupling theory (MCT) which predict a sharp ergodicity-non-ergodicity transition at a critical density. The single particle dynamics in the non-ergodic state, treated approximately, represents a propagating mode whose characteristic frequency is computed from the corresponding memory function of the MCT. The mass localization parameters in the above two models (treated in their simplest forms) are obtained, respectively, in terms of the corresponding natural frequencies depicted and are shown to have comparable magnitudes.
-
Linking density functional and mode coupling models for supercooled liquids
Energy Technology Data Exchange (ETDEWEB)
Premkumar, Leishangthem; Bidhoodi, Neeta; Das, Shankar P. [School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India)
2016-03-28
We compare predictions from two familiar models of the metastable supercooled liquid, respectively, constructed with thermodynamic and dynamic approaches. In the so called density functional theory the free energy F[ρ] of the liquid is a functional of the inhomogeneous density ρ(r). The metastable state is identified as a local minimum of F[ρ]. The sharp density profile characterizing ρ(r) is identified as a single particle oscillator, whose frequency is obtained from the parameters of the optimum density function. On the other hand, a dynamic approach to supercooled liquids is taken in the mode coupling theory (MCT) which predict a sharp ergodicity-non-ergodicity transition at a critical density. The single particle dynamics in the non-ergodic state, treated approximately, represents a propagating mode whose characteristic frequency is computed from the corresponding memory function of the MCT. The mass localization parameters in the above two models (treated in their simplest forms) are obtained, respectively, in terms of the corresponding natural frequencies depicted and are shown to have comparable magnitudes.
-
Garcia-Seisdedos, Hector; Ibarra-Molero, Beatriz; Sanchez-Ruiz, Jose M
2012-01-01
Protein promiscuity is of considerable interest due its role in adaptive metabolic plasticity, its fundamental connection with molecular evolution and also because of its biotechnological applications. Current views on the relation between primary and promiscuous protein activities stem largely from laboratory evolution experiments aimed at increasing promiscuous activity levels. Here, on the other hand, we attempt to assess the main features of the simultaneous modulation of the primary and promiscuous functions during the course of natural evolution. The computational/experimental approach we propose for this task involves the following steps: a function-targeted, statistical coupling analysis of evolutionary data is used to determine a set of positions likely linked to the recruitment of a promiscuous activity for a new function; a combinatorial library of mutations on this set of positions is prepared and screened for both, the primary and the promiscuous activities; a partial-least-squares reconstruction of the full combinatorial space is carried out; finally, an approximation to the Pareto set of variants with optimal primary/promiscuous activities is derived. Application of the approach to the emergence of folding catalysis in thioredoxin scaffolds reveals an unanticipated scenario: diverse patterns of primary/promiscuous activity modulation are possible, including a moderate (but likely significant in a biological context) simultaneous enhancement of both activities. We show that this scenario can be most simply explained on the basis of the conformational diversity hypothesis, although alternative interpretations cannot be ruled out. Overall, the results reported may help clarify the mechanisms of the evolution of new functions. From a different viewpoint, the partial-least-squares-reconstruction/Pareto-set-prediction approach we have introduced provides the computational basis for an efficient directed-evolution protocol aimed at the simultaneous
-
Longitudinal Links between Executive Function, Anger, and Aggression in Middle Childhood
Rohlf, Helena L.; Holl, Anna K.; Kirsch, Fabian; Krahé, Barbara; Elsner, Birgit
2018-01-01
Previous research has indicated that executive function (EF) is negatively associated with aggressive behavior in childhood. However, there is a lack of longitudinal studies that have examined the effect of deficits in EF on aggression over time and taken into account different forms and functions of aggression at the same time. Furthermore, only few studies have analyzed the role of underlying variables that may explain the association between EF and aggression. The present study examined the prospective paths between EF and different forms (physical and relational) and functions (reactive and proactive) of aggression. The habitual experience of anger was examined as a potential underlying mechanism of the link between EF and aggression, because the tendency to get angry easily has been found to be both a consequence of deficits in EF and a predictor of aggression. The study included 1,652 children (between 6 and 11 years old at the first time point), who were followed over three time points (T1, T2, and T3) covering 3 years. At T1, a latent factor of EF comprised measures of planning, rated via teacher reports, as well as inhibition, set shifting, and working-memory updating, assessed experimentally. Habitual anger experience was assessed via parent reports at T1 and T2. The forms and functions of aggression were measured via teacher reports at all three time points. Structural equation modeling revealed that EF at T1 predicted physical, relational, and reactive aggression at T3, but was unrelated to proactive aggression at T3. Furthermore, EF at T1 was indirectly linked to physical aggression at T3, mediated through habitual anger experience at T2. The results indicate that deficits in EF influence the later occurrence of aggression in middle childhood, and the tendency to get angry easily mediates this relation. PMID:29535615
-
Longitudinal Links between Executive Function, Anger, and Aggression in Middle Childhood
Directory of Open Access Journals (Sweden)
Helena L. Rohlf
2018-02-01
Full Text Available Previous research has indicated that executive function (EF is negatively associated with aggressive behavior in childhood. However, there is a lack of longitudinal studies that have examined the effect of deficits in EF on aggression over time and taken into account different forms and functions of aggression at the same time. Furthermore, only few studies have analyzed the role of underlying variables that may explain the association between EF and aggression. The present study examined the prospective paths between EF and different forms (physical and relational and functions (reactive and proactive of aggression. The habitual experience of anger was examined as a potential underlying mechanism of the link between EF and aggression, because the tendency to get angry easily has been found to be both a consequence of deficits in EF and a predictor of aggression. The study included 1,652 children (between 6 and 11 years old at the first time point, who were followed over three time points (T1, T2, and T3 covering 3 years. At T1, a latent factor of EF comprised measures of planning, rated via teacher reports, as well as inhibition, set shifting, and working-memory updating, assessed experimentally. Habitual anger experience was assessed via parent reports at T1 and T2. The forms and functions of aggression were measured via teacher reports at all three time points. Structural equation modeling revealed that EF at T1 predicted physical, relational, and reactive aggression at T3, but was unrelated to proactive aggression at T3. Furthermore, EF at T1 was indirectly linked to physical aggression at T3, mediated through habitual anger experience at T2. The results indicate that deficits in EF influence the later occurrence of aggression in middle childhood, and the tendency to get angry easily mediates this relation.
-
Defining mental disorder. Exploring the 'natural function' approach.
Varga, Somogy
2011-01-21
Due to several socio-political factors, to many psychiatrists only a strictly objective definition of mental disorder, free of value components, seems really acceptable. In this paper, I will explore a variant of such an objectivist approach to defining metal disorder, natural function objectivism. Proponents of this approach make recourse to the notion of natural function in order to reach a value-free definition of mental disorder. The exploration of Christopher Boorse's 'biostatistical' account of natural function (1) will be followed an investigation of the 'hybrid naturalism' approach to natural functions by Jerome Wakefield (2). In the third part, I will explore two proposals that call into question the whole attempt to define mental disorder (3). I will conclude that while 'natural function objectivism' accounts fail to provide the backdrop for a reliable definition of mental disorder, there is no compelling reason to conclude that a definition cannot be achieved.
-
Xu, Chuanhui; Cao, Liming; Lin, Baofeng; Liang, Xingquan; Chen, Yukun
2016-07-13
Introducing ionic associations is one of the most effective approaches to realize a self-healing behavior for rubbers. However, most of commercial rubbers are nonpolar rubbers without now available functional groups to be converted into ionic groups. In this paper, our strategy was based on a controlled peroxide-induced vulcanization to generate massive ionic cross-links via polymerization of zinc dimethacrylate (ZDMA) in natural rubber (NR) and exploited it as a potential self-healable material. We controlled vulcanization process to retard the formation of covalent cross-link network, and successfully generated a reversible supramolecular network mainly constructed by ionic cross-links. Without the restriction of covalent cross-linkings, the NR chains in ionic supramolecular network had good flexibility and mobility. The nature that the ionic cross-links was easily reconstructed and rearranged facilitating the self-healing behavior, thereby enabling a fully cut sample to rejoin and retain to its original properties after a suitable self-healing process at ambient temperature. This study thus demonstrates a feasible approach to impart an ionic association induced self-healing function to commercial rubbers without ionic functional groups.
-
Linking biological soil crust diversity to ecological functions
Glaser, Karin; Borchhardt, Nadine; Schulz, Karoline; Mikhailyuk, Tatiana; Baumann, Karen; Leinweber, Peter; Ulf, Karsten
2016-04-01
Biological soil crusts (BSCs) are an association of different microorganisms and soil particles in the top millimeters of the soil. They are formed by algae, cyanobacteria, microfungi, bacteria, bryophytes and lichens in various compositions. Our aim was to determine and compare the biodiversity of all occurring organisms in biogeographically different habitats, ranging from polar (both Arctic and Antarctic), subpolar (Scandinavia), temperate (Germany) to dry regions (Chile). The combination of microscopy and molecular techniques (next-generation sequencing) revealed highly diverse crust communities, whose composition clustered by region and correlates with habitat characteristics such as water content. The BSC biodiversity was then linked to the ecological function of the crusts. The functional role of the BSCs in the biogeochemical cycles of carbon, nitrogen and phosphorous is evaluated using an array of state of the art soil chemistry methods including Py-FIMS (pyrolysis field ionization mass spectrometry) and XANES (x-ray absorbance near edge structure). Total P as well as P fractions were quantified in all BSCs, adjacent soil underneath and comparable nearby soil of BSC-free areas revealing a remarkable accumulation of total phosphorous and a distinct pattern of P fractions in the crust. Further, we observed an indication of a different P-speciation composition in the crust compared with BSC-free soil. The data allow answering the question whether BSCs act as sink or source for these compounds, and how biodiversity controls the biogeochemical function of BSCs.
-
da Silva, Pedro Giovâni; Hernández, Malva Isabel Medina
2015-01-01
Community structure is driven by mechanisms linked to environmental, spatial and temporal processes, which have been successfully addressed using metacommunity framework. The relative importance of processes shaping community structure can be identified using several different approaches. Two approaches that are increasingly being used are functional diversity and community deconstruction. Functional diversity is measured using various indices that incorporate distinct community attributes. Community deconstruction is a way to disentangle species responses to ecological processes by grouping species with similar traits. We used these two approaches to determine whether they are improvements over traditional measures (e.g., species composition, abundance, biomass) for identification of the main processes driving dung beetle (Scarabaeinae) community structure in a fragmented mainland-island landscape in southern Brazilian Atlantic Forest. We sampled five sites in each of four large forest areas, two on the mainland and two on the island. Sampling was performed in 2012 and 2013. We collected abundance and biomass data from 100 sampling points distributed over 20 sampling sites. We studied environmental, spatial and temporal effects on dung beetle community across three spatial scales, i.e., between sites, between areas and mainland-island. The γ-diversity based on species abundance was mainly attributed to β-diversity as a consequence of the increase in mean α- and β-diversity between areas. Variation partitioning on abundance, biomass and functional diversity showed scale-dependence of processes structuring dung beetle metacommunities. We identified two major groups of responses among 17 functional groups. In general, environmental filters were important at both local and regional scales. Spatial factors were important at the intermediate scale. Our study supports the notion of scale-dependence of environmental, spatial and temporal processes in the distribution
-
Choi, Ji Yeh; Hwang, Heungsun; Yamamoto, Michio; Jung, Kwanghee; Woodward, Todd S
2017-06-01
Functional principal component analysis (FPCA) and functional multiple-set canonical correlation analysis (FMCCA) are data reduction techniques for functional data that are collected in the form of smooth curves or functions over a continuum such as time or space. In FPCA, low-dimensional components are extracted from a single functional dataset such that they explain the most variance of the dataset, whereas in FMCCA, low-dimensional components are obtained from each of multiple functional datasets in such a way that the associations among the components are maximized across the different sets. In this paper, we propose a unified approach to FPCA and FMCCA. The proposed approach subsumes both techniques as special cases. Furthermore, it permits a compromise between the techniques, such that components are obtained from each set of functional data to maximize their associations across different datasets, while accounting for the variance of the data well. We propose a single optimization criterion for the proposed approach, and develop an alternating regularized least squares algorithm to minimize the criterion in combination with basis function approximations to functions. We conduct a simulation study to investigate the performance of the proposed approach based on synthetic data. We also apply the approach for the analysis of multiple-subject functional magnetic resonance imaging data to obtain low-dimensional components of blood-oxygen level-dependent signal changes of the brain over time, which are highly correlated across the subjects as well as representative of the data. The extracted components are used to identify networks of neural activity that are commonly activated across the subjects while carrying out a working memory task.
-
Defining mental disorder. Exploring the 'natural function' approach
Directory of Open Access Journals (Sweden)
Varga Somogy
2011-01-01
Full Text Available Abstract Due to several socio-political factors, to many psychiatrists only a strictly objective definition of mental disorder, free of value components, seems really acceptable. In this paper, I will explore a variant of such an objectivist approach to defining metal disorder, natural function objectivism. Proponents of this approach make recourse to the notion of natural function in order to reach a value-free definition of mental disorder. The exploration of Christopher Boorse's 'biostatistical' account of natural function (1 will be followed an investigation of the 'hybrid naturalism' approach to natural functions by Jerome Wakefield (2. In the third part, I will explore two proposals that call into question the whole attempt to define mental disorder (3. I will conclude that while 'natural function objectivism' accounts fail to provide the backdrop for a reliable definition of mental disorder, there is no compelling reason to conclude that a definition cannot be achieved.
-
Directory of Open Access Journals (Sweden)
Harmelin–Vivien, M. L.
2009-12-01
Full Text Available Continental particulate organic matter (POM plays a major role in the functioning of coastal marine ecosystems as a disturbance as well as an input of nutrients. Relationships linking continental inputs from the Rhone River to biodiversity of the coastal benthic ecosystem and fishery production were investigated in the Golfe du Lion (NW Mediterranean Sea. Macrobenthic community diversity decreased when continen¬tal inputs of organic matter increased, whereas ecosystem production, measured by common sole (Solea solea fishery yields in the area, increased. Decreases in macrobenthic diversity were mainly related to an increasing abundance of species with specific functional traits, particularly deposit-feeding polychaetes. The decrease in macrobenthic diversity did not result in a decrease, but an increase in ecosystem production, as it enhanced the transfer of continental POM into marine food webs. The present study showed that it is necessary to consider functional traits of species, direct and indirect links between species, and feedback loops to understand the effects of biodiversity on ecosystem functioning and productivity.
-
Introducing linear functions: an alternative statistical approach
Nolan, Caroline; Herbert, Sandra
2015-12-01
The introduction of linear functions is the turning point where many students decide if mathematics is useful or not. This means the role of parameters and variables in linear functions could be considered to be `threshold concepts'. There is recognition that linear functions can be taught in context through the exploration of linear modelling examples, but this has its limitations. Currently, statistical data is easily attainable, and graphics or computer algebra system (CAS) calculators are common in many classrooms. The use of this technology provides ease of access to different representations of linear functions as well as the ability to fit a least-squares line for real-life data. This means these calculators could support a possible alternative approach to the introduction of linear functions. This study compares the results of an end-of-topic test for two classes of Australian middle secondary students at a regional school to determine if such an alternative approach is feasible. In this study, test questions were grouped by concept and subjected to concept by concept analysis of the means of test results of the two classes. This analysis revealed that the students following the alternative approach demonstrated greater competence with non-standard questions.
-
Executive Function and Food Approach Behavior in Middle Childhood
Directory of Open Access Journals (Sweden)
Karoline eGroppe
2014-05-01
Full Text Available Executive function (EF has long been considered to be a unitary, domain-general cognitive ability. However, recent research suggests differentiating ‘hot’ affective and ‘cool’ cognitive aspects of EF. Yet, findings regarding this two-factor construct are still inconsistent. In particular, the development of this factor structure remains unclear and data on school-aged children is lacking. Furthermore, studies linking EF and overweight or obesity suggest that EF contributes to the regulation of eating behavior. So far, however, the links between EF and eating behavior have rarely been investigated in children and non-clinical populations.First, we examined whether EF can be divided into hot and cool factors or whether they actually correspond to a unitary construct in middle childhood. Second, we examined how hot and cool EF are associated with different eating styles that put children at risk of becoming overweight during development. Hot and cool EF were assessed experimentally in a non-clinical population of 1,657 elementary-school children (aged 6-11 years. The ‘food approach’ behavior was rated mainly via parent questionnaires.Findings indicate that hot EF is distinguishable from cool EF. However, only cool EF seems to represent a coherent functional entity, whereas hot EF does not seem to be a homogenous construct. This was true for a younger and an older subgroup of children. Furthermore, different EF components were correlated with eating styles, such as responsiveness to food, desire to drink, and restrained eating in girls but not in boys. This shows that lower levels of EF are not only seen in clinical populations of obese patients but are already associated with food approach styles in a normal population of elementary school-aged girls. Although the direction of effect still has to be clarified, results point to the possibility that EF constitutes a risk factor for eating styles contributing to the development of
-
International Nuclear Information System (INIS)
Basiuk, Elena V.; Basiuk, Vladimir A.; Meza-Laguna, Víctor; Contreras-Torres, Flavio F.; Martínez, Melchor; Rojas-Aguilar, Aarón; Salerno, Marco
2012-01-01
Highlights: ► Diamines were used for one-step functionalization of nanotubes and nanodiamond. ► We found experimental evidences of cross-linking effects in these nanomaterials. ► We found a strong orientation effect in the functionalized carbon nanotubes. - Abstract: The covalent functionalization of carbon nanomaterials with diamines is a way to enhance the mechanical strength of nanocomposites due to cross-linking effects, to form complex networks for nanotube-based electronic circuits, as well as is important for a number of biomedical applications. The main goal of the present work was to covalently functionalize pristine multi-walled carbon nanotubes and nanodiamond with three aliphatic diamines (1,8-diaminooctane, 1,10-diaminodecane and 1,12-diaminododecane) and one aromatic diamine (1,5-diaminonaphthalene), by employing a simple one-step solvent-free methodology, which is based on thermal instead of chemical activation. We looked for experimental evidences of cross-linking effects in the carbon nanomaterials synthesized by using solubility/dispersibility tests, atomic force microscopy, scanning and transmission electron microscopy, as well as Fourier-transform infrared spectroscopy and thermogravimetric analysis for additional characterization.
-
Griskevicius, Vladas; Shiota, Michelle N; Neufeld, Samantha L
2010-04-01
Much research has found that positive affect facilitates increased reliance on heuristics in cognition. However, theories proposing distinct evolutionary fitness-enhancing functions for specific positive emotions also predict important differences among the consequences of different positive emotion states. Two experiments investigated how six positive emotions influenced the processing of persuasive messages. Using different methods to induce emotions and assess processing, we showed that the positive emotions of anticipatory enthusiasm, amusement, and attachment love tended to facilitate greater acceptance of weak persuasive messages (consistent with previous research), whereas the positive emotions of awe and nurturant love reduced persuasion by weak messages. In addition, a series of mediation analyses suggested that the effects distinguishing different positive emotions from a neutral control condition were best accounted for by different mediators rather than by one common mediator. These findings build upon approaches that link affective valence to certain types of processing, documenting emotion-specific effects on cognition that are consistent with functional evolutionary accounts of discrete positive emotions. Copyright 2010 APA, all rights reserved.
-
2005-01-01
This document provides a study of the technical literature related to Command and Control (C2) link security for Unmanned Aircraft Systems (UAS) for operation in the National Airspace System (NAS). Included is a preliminary set of functional requirements for C2 link security.
-
Transient management using the safety function approach
International Nuclear Information System (INIS)
Corcoran, W.R.; Barrow, J.H.; Bischoff, G.C.; Callaghan, V.M.; Pearce, R.T.
1984-01-01
The safety function approach is described. Its use in the development of a transient management procedures system includes optimal recovery procedures tailored to specific, anticipated symptom sets and a functional recovery procedure which is more general. Simulator evaluations are described
-
MeMo: a hybrid SQL/XML approach to metabolomic data management for functional genomics
Directory of Open Access Journals (Sweden)
Hardy Nigel
2006-06-01
Full Text Available Abstract Background The genome sequencing projects have shown our limited knowledge regarding gene function, e.g. S. cerevisiae has 5–6,000 genes of which nearly 1,000 have an uncertain function. Their gross influence on the behaviour of the cell can be observed using large-scale metabolomic studies. The metabolomic data produced need to be structured and annotated in a machine-usable form to facilitate the exploration of the hidden links between the genes and their functions. Description MeMo is a formal model for representing metabolomic data and the associated metadata. Two predominant platforms (SQL and XML are used to encode the model. MeMo has been implemented as a relational database using a hybrid approach combining the advantages of the two technologies. It represents a practical solution for handling the sheer volume and complexity of the metabolomic data effectively and efficiently. The MeMo model and the associated software are available at http://dbkgroup.org/memo/. Conclusion The maturity of relational database technology is used to support efficient data processing. The scalability and self-descriptiveness of XML are used to simplify the relational schema and facilitate the extensibility of the model necessitated by the creation of new experimental techniques. Special consideration is given to data integration issues as part of the systems biology agenda. MeMo has been physically integrated and cross-linked to related metabolomic and genomic databases. Semantic integration with other relevant databases has been supported through ontological annotation. Compatibility with other data formats is supported by automatic conversion.
-
Directory of Open Access Journals (Sweden)
Liang Meng
Full Text Available A fundamental issue in neuroscience is how to identify the multiple biophysical mechanisms through which neurons generate observed patterns of spiking activity. In previous work, we proposed a method for linking observed patterns of spiking activity to specific biophysical mechanisms based on a state space modeling framework and a sequential Monte Carlo, or particle filter, estimation algorithm. We have shown, in simulation, that this approach is able to identify a space of simple biophysical models that were consistent with observed spiking data (and included the model that generated the data, but have yet to demonstrate the application of the method to identify realistic currents from real spike train data. Here, we apply the particle filter to spiking data recorded from rat layer V cortical neurons, and correctly identify the dynamics of an slow, intrinsic current. The underlying intrinsic current is successfully identified in four distinct neurons, even though the cells exhibit two distinct classes of spiking activity: regular spiking and bursting. This approach--linking statistical, computational, and experimental neuroscience--provides an effective technique to constrain detailed biophysical models to specific mechanisms consistent with observed spike train data.
-
Verlinde, Christophe L. M. J.; Rudenko, Gabrielle; Hol, Wim G. J.
1992-04-01
A modular method for pursuing structure-based inhibitor design in the framework of a design cycle is presented. The approach entails four stages: (1) a design pathway is defined in the three-dimensional structure of a target protein; (2) this pathway is divided into subregions; (3) complementary building blocks, also called fragments, are designed in each subregion; complementarity is defined in terms of shape, hydrophobicity, hydrogen bond properties and electrostatics; and (4) fragments from different subregions are linked into potential lead compounds. Stages (3) and (4) are qualitatively guided by force-field calculations. In addition, the designed fragments serve as entries for retrieving existing compounds from chemical databases. This linked-fragment approach has been applied in the design of potentially selective inhibitors of triosephosphate isomerase from Trypanosoma brucei, the causative agent of sleeping sickness.
-
Zhang, Z.; Toyer, S.; Brizhinev, D.; Ledger, M.; Taylor, K.; Purss, M. B. J.
2016-12-01
We are witnessing a rapid proliferation of geoscientific and geospatial data from an increasing variety of sensors and sensor networks. This data presents great opportunities to resolve cross-disciplinary problems. However, working with it often requires an understanding of file formats and protocols seldom used outside of scientific computing, potentially limiting the data's value to other disciplines. In this paper, we present a new approach to serving satellite coverage data on the web, which improves ease-of-access using the principles of linked data. Linked data adapts the concepts and protocols of the human-readable web to machine-readable data; the number of developers familiar with web technologies makes linked data a natural choice for bringing coverages to a wider audience. Our approach to using linked data also makes it possible to efficiently service high-level SPARQL queries: for example, "Retrieve all Landsat ETM+ observations of San Francisco between July and August 2016" can easily be encoded in a single query. We validate the new approach, which we call QBCov, with a reference implementation of the entire stack, including a simple web-based client for interacting with Landsat observations. In addition to demonstrating the utility of linked data for publishing coverages, we investigate the heretofore unexplored relationship between Discrete Global Grid Systems (DGGS) and linked data. Our conclusions are informed by the aforementioned reference implementation of QBCov, which is backed by a hierarchical file format designed around the rHEALPix DGGS. Not only does the choice of a DGGS-based representation provide an efficient mechanism for accessing large coverages at multiple scales, but the ability of DGGS to produce persistent, unique identifiers for spatial regions is especially valuable in a linked data context. This suggests that DGGS has an important role to play in creating sustainable and scalable linked data infrastructures. QBCov is being
-
Energy Technology Data Exchange (ETDEWEB)
Basiuk, Elena V., E-mail: elenagd@unam.mx [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico); Nanophysics Department, Italian Institute of Technology, via Morego 30, 16163 Genova, Liguria (Italy); Basiuk, Vladimir A. [Nanophysics Department, Italian Institute of Technology, via Morego 30, 16163 Genova, Liguria (Italy); Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico); Facultad de Ciencias, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, Col. Chamilpa, 62209 Cuernavaca, Morelos (Mexico); Meza-Laguna, Victor; Contreras-Torres, Flavio F.; Martinez, Melchor [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico); Rojas-Aguilar, Aaron [Centro de Investigacion y de Estudios Avanzados, Instituto Politecnico Nacional, Av. Instituto Politecnico Nacional 2508, Col. San Pedro Zacatenco, 07360 Mexico, D.F. (Mexico); Salerno, Marco [Nanophysics Department, Italian Institute of Technology, via Morego 30, 16163 Genova, Liguria (Italy); and others
2012-10-15
Highlights: Black-Right-Pointing-Pointer Diamines were used for one-step functionalization of nanotubes and nanodiamond. Black-Right-Pointing-Pointer We found experimental evidences of cross-linking effects in these nanomaterials. Black-Right-Pointing-Pointer We found a strong orientation effect in the functionalized carbon nanotubes. - Abstract: The covalent functionalization of carbon nanomaterials with diamines is a way to enhance the mechanical strength of nanocomposites due to cross-linking effects, to form complex networks for nanotube-based electronic circuits, as well as is important for a number of biomedical applications. The main goal of the present work was to covalently functionalize pristine multi-walled carbon nanotubes and nanodiamond with three aliphatic diamines (1,8-diaminooctane, 1,10-diaminodecane and 1,12-diaminododecane) and one aromatic diamine (1,5-diaminonaphthalene), by employing a simple one-step solvent-free methodology, which is based on thermal instead of chemical activation. We looked for experimental evidences of cross-linking effects in the carbon nanomaterials synthesized by using solubility/dispersibility tests, atomic force microscopy, scanning and transmission electron microscopy, as well as Fourier-transform infrared spectroscopy and thermogravimetric analysis for additional characterization.
-
Amartya Sen's Capability Approach and Education
Walker, Melanie
2005-01-01
The human capabilities approach developed by the economist Amartya Sen links development, quality of life and freedom. This article explores the key ideas in the capability approach of: capability, functioning, agency, human diversity and public participation in generating valued capabilities. It then considers how these ideas relate specifically…
-
Adversity in childhood linked to elevated striatal dopamine function in adulthood.
Egerton, Alice; Valmaggia, Lucia R; Howes, Oliver D; Day, Fern; Chaddock, Christopher A; Allen, Paul; Winton-Brown, Toby T; Bloomfield, Michael A P; Bhattacharyya, Sagnik; Chilcott, Jack; Lappin, Julia M; Murray, Robin M; McGuire, Philip
2016-10-01
Childhood adversity increases the risk of psychosis in adulthood. Theoretical and animal models suggest that this effect may be mediated by increased striatal dopamine neurotransmission. The primary objective of this study was to examine the relationship between adversity in childhood and striatal dopamine function in early adulthood. Secondary objectives were to compare exposure to childhood adversity and striatal dopamine function in young people at ultra high risk (UHR) of psychosis and healthy volunteers. Sixty-seven young adults, comprising 47 individuals at UHR for psychosis and 20 healthy volunteers were recruited from the same geographic area and were matched for age, gender and substance use. Presynaptic dopamine function in the associative striatum was assessed using 18F-DOPA positron emission tomography. Childhood adversity was assessed using the Childhood Experience of Care and Abuse questionnaire. Within the sample as a whole, both severe physical or sexual abuse (T63=2.92; P=0.005), and unstable family arrangements (T57=2.80; P=0.007) in childhood were associated with elevated dopamine function in the associative striatum in adulthood. Comparison of the UHR and volunteer subgroups revealed similar incidence of childhood adverse experiences, and there was no significant group difference in dopamine function. This study provides evidence that childhood adversity is linked to elevated striatal dopamine function in adulthood. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
-
Functional Divergence in the Role of N-Linked Glycosylation in Smoothened Signaling.
Directory of Open Access Journals (Sweden)
Suresh Marada
2015-08-01
Full Text Available The G protein-coupled receptor (GPCR Smoothened (Smo is the requisite signal transducer of the evolutionarily conserved Hedgehog (Hh pathway. Although aspects of Smo signaling are conserved from Drosophila to vertebrates, significant differences have evolved. These include changes in its active sub-cellular localization, and the ability of vertebrate Smo to induce distinct G protein-dependent and independent signals in response to ligand. Whereas the canonical Smo signal to Gli transcriptional effectors occurs in a G protein-independent manner, its non-canonical signal employs Gαi. Whether vertebrate Smo can selectively bias its signal between these routes is not yet known. N-linked glycosylation is a post-translational modification that can influence GPCR trafficking, ligand responsiveness and signal output. Smo proteins in Drosophila and vertebrate systems harbor N-linked glycans, but their role in Smo signaling has not been established. Herein, we present a comprehensive analysis of Drosophila and murine Smo glycosylation that supports a functional divergence in the contribution of N-linked glycans to signaling. Of the seven predicted glycan acceptor sites in Drosophila Smo, one is essential. Loss of N-glycosylation at this site disrupted Smo trafficking and attenuated its signaling capability. In stark contrast, we found that all four predicted N-glycosylation sites on murine Smo were dispensable for proper trafficking, agonist binding and canonical signal induction. However, the under-glycosylated protein was compromised in its ability to induce a non-canonical signal through Gαi, providing for the first time evidence that Smo can bias its signal and that a post-translational modification can impact this process. As such, we postulate a profound shift in N-glycan function from affecting Smo ER exit in flies to influencing its signal output in mice.
-
Functional integral approach to classical statistical dynamics
International Nuclear Information System (INIS)
Jensen, R.V.
1980-04-01
A functional integral method is developed for the statistical solution of nonlinear stochastic differential equations which arise in classical dynamics. The functional integral approach provides a very natural and elegant derivation of the statistical dynamical equations that have been derived using the operator formalism of Martin, Siggia, and Rose
-
Stephens, Jaclyn A; Salorio, Cynthia F; Barber, Anita D; Risen, Sarah R; Mostofsky, Stewart H; Suskauer, Stacy J
2017-07-10
This study examined functional connectivity of the default mode network (DMN) and examined brain-behavior relationships in a pilot cohort of children with chronic mild to moderate traumatic brain injury (TBI). Compared to uninjured peers, children with TBI demonstrated less anti-correlated functional connectivity between DMN and right Brodmann Area 40 (BA 40). In children with TBI, more anomalous less anti-correlated) connectivity between DMN and right BA 40 was linked to poorer performance on response inhibition tasks. Collectively, these preliminary findings suggest that functional connectivity between DMN and BA 40 may relate to longterm functional outcomes in chronic pediatric TBI.
-
Directory of Open Access Journals (Sweden)
Kunjumon I Vadakkan
2011-07-01
Full Text Available The internal sensation of memory, which is available only to the owner of an individual nervous system, is difficult to analyze for its basic elements of operation. We hypothesize that associative learning induces the formation of functional LINK between the postsynapses. During memory retrieval, the activation of either postsynapse re-activates the functional LINK evoking a semblance of sensory activity arriving at its opposite postsynapse, nature of which defines the basic unit of virtual internal sensation - namely, semblion. Neuronal networks that undergo continuous oscillatory activity at certain levels of their organization induce semblions enabling the system to continuously learn, self-organize, and demonstrate instantiation, features that can be utilized for developing artificial intelligence (AI. Suitability of the inter-postsynaptic functional LINKs to meet the expectations of Minsky’s K-lines, basic elements of a memory theory generated to develop AI and methods to replicate semblances outside the nervous system are explained.
-
An Approach for Integrating the Prioritization of Functional and Nonfunctional Requirements
Directory of Open Access Journals (Sweden)
Mohammad Dabbagh
2014-01-01
Full Text Available Due to the budgetary deadlines and time to market constraints, it is essential to prioritize software requirements. The outcome of requirements prioritization is an ordering of requirements which need to be considered first during the software development process. To achieve a high quality software system, both functional and nonfunctional requirements must be taken into consideration during the prioritization process. Although several requirements prioritization methods have been proposed so far, no particular method or approach is presented to consider both functional and nonfunctional requirements during the prioritization stage. In this paper, we propose an approach which aims to integrate the process of prioritizing functional and nonfunctional requirements. The outcome of applying the proposed approach produces two separate prioritized lists of functional and non-functional requirements. The effectiveness of the proposed approach has been evaluated through an empirical experiment aimed at comparing the approach with the two state-of-the-art-based approaches, analytic hierarchy process (AHP and hybrid assessment method (HAM. Results show that our proposed approach outperforms AHP and HAM in terms of actual time-consumption while preserving the quality of the results obtained by our proposed approach at a high level of agreement in comparison with the results produced by the other two approaches.
-
An approach for integrating the prioritization of functional and nonfunctional requirements.
Dabbagh, Mohammad; Lee, Sai Peck
2014-01-01
Due to the budgetary deadlines and time to market constraints, it is essential to prioritize software requirements. The outcome of requirements prioritization is an ordering of requirements which need to be considered first during the software development process. To achieve a high quality software system, both functional and nonfunctional requirements must be taken into consideration during the prioritization process. Although several requirements prioritization methods have been proposed so far, no particular method or approach is presented to consider both functional and nonfunctional requirements during the prioritization stage. In this paper, we propose an approach which aims to integrate the process of prioritizing functional and nonfunctional requirements. The outcome of applying the proposed approach produces two separate prioritized lists of functional and non-functional requirements. The effectiveness of the proposed approach has been evaluated through an empirical experiment aimed at comparing the approach with the two state-of-the-art-based approaches, analytic hierarchy process (AHP) and hybrid assessment method (HAM). Results show that our proposed approach outperforms AHP and HAM in terms of actual time-consumption while preserving the quality of the results obtained by our proposed approach at a high level of agreement in comparison with the results produced by the other two approaches.
-
Assessment of cockpit interface concepts for data link retrofit
Mccauley, Hugh W.; Miles, William L.; Dwyer, John P.; Erickson, Jeffery B.
1992-01-01
The problem is examined of retrofitting older generation aircraft with data link capability. The approach taken analyzes requirements for the cockpit interface, based on review of prior research and opinions obtained from subject matter experts. With this background, essential functions and constraints for a retrofit installation are defined. After an assessment of the technology available to meet the functions and constraints, candidate design concepts are developed. The most promising design concept is described in detail. Finally, needs for further research and development are identified.
-
Bridgett, David J; Oddi, Kate B; Laake, Lauren M; Murdock, Kyle W; Bachmann, Melissa N
2013-02-01
Subdisciplines within psychology frequently examine self-regulation from different frameworks despite conceptually similar definitions of constructs. In the current study, similarities and differences between effortful control, based on the psychobiological model of temperament (Rothbart, Derryberry, & Posner, 1994), and executive functioning are examined and empirically tested in three studies (n = 509). Structural equation modeling indicated that effortful control and executive functioning are strongly associated and overlapping constructs (Study 1). Additionally, results indicated that effortful control is related to the executive function of updating/monitoring information in working memory, but not inhibition (Studies 2 and 3). Study 3 also demonstrates that better updating/monitoring information in working memory and better effortful control were uniquely linked to lower dispositional negative affect, whereas the executive function of low/poor inhibition was uniquely associated with an increased tendency to express negative affect. Furthermore, dispositional negative affect mediated the links between effortful control and, separately, the executive function of updating/monitoring information in working memory and the tendency to express negative affect. The theoretical implications of these findings are discussed, and a potential framework for guiding future work directed at integrating and differentiating aspects of self-regulation is suggested. PsycINFO Database Record (c) 2013 APA, all rights reserved.
-
Function of dynamic models in systems biology: linking structure to behaviour.
Knüpfer, Christian; Beckstein, Clemens
2013-10-08
Dynamic models in Systems Biology are used in computational simulation experiments for addressing biological questions. The complexity of the modelled biological systems and the growing number and size of the models calls for computer support for modelling and simulation in Systems Biology. This computer support has to be based on formal representations of relevant knowledge fragments. In this paper we describe different functional aspects of dynamic models. This description is conceptually embedded in our "meaning facets" framework which systematises the interpretation of dynamic models in structural, functional and behavioural facets. Here we focus on how function links the structure and the behaviour of a model. Models play a specific role (teleological function) in the scientific process of finding explanations for dynamic phenomena. In order to fulfil this role a model has to be used in simulation experiments (pragmatical function). A simulation experiment always refers to a specific situation and a state of the model and the modelled system (conditional function). We claim that the function of dynamic models refers to both the simulation experiment executed by software (intrinsic function) and the biological experiment which produces the phenomena under investigation (extrinsic function). We use the presented conceptual framework for the function of dynamic models to review formal accounts for functional aspects of models in Systems Biology, such as checklists, ontologies, and formal languages. Furthermore, we identify missing formal accounts for some of the functional aspects. In order to fill one of these gaps we propose an ontology for the teleological function of models. We have thoroughly analysed the role and use of models in Systems Biology. The resulting conceptual framework for the function of models is an important first step towards a comprehensive formal representation of the functional knowledge involved in the modelling and simulation process
-
Combining formal and functional approaches to topic structure
Zellers, M.; Post, B.
2012-01-01
Fragmentation between formal and functional approaches to prosodic variation is an ongoing problem in linguistic research. In particular, the frameworks of the Phonetics of Talk-in-Interaction (PTI) and Empirical Phonology (EP) take very different theoretical and methodological approaches to this
-
Linking epigenetic function to electrostatics: The DNMT2 structural model example.
Vieira, Gilberto Cavalheiro; Vieira, Gustavo Fioravanti; Sinigaglia, Marialva; Silva Valente, Vera Lúcia da
2017-01-01
The amino acid sequence of DNMT2 is very similar to the catalytic domains of bacterial and eukaryotic proteins. However, there is great variability in the region of recognition of the target sequence. While bacterial DNMT2 acts as a DNA methyltransferase, previous studies have indicated low DNA methylation activity in eukaryotic DNMT2, with preference by tRNA methylation. Drosophilids are known as DNMT2-only species and the DNA methylation phenomenon is a not elucidated case yet, as well as the ontogenetic and physiologic importance of DNMT2 for this species group. In addition, more recently study showed that methylation in the genome in Drosophila melanogaster is independent in relation to DNMT2. Despite these findings, Drosophilidae family has more than 4,200 species with great ecological diversity and historical evolution, thus we, therefore, aimed to examine the drosophilids DNMT2 in order to verify its conservation at the physicochemical and structural levels in a functional context. We examined the twenty-six DNMT2 models generated by molecular modelling and five crystallographic structures deposited in the Protein Data Bank (PDB) using different approaches. Our results showed that despite sequence and structural similarity between species close related, we found outstanding differences when they are analyzed in the context of surface distribution of electrostatic properties. The differences found in the electrostatic potentials may be linked with different affinities and processivity of DNMT2 for its different substrates (DNA, RNA or tRNA) and even for interactions with other proteins involved in the epigenetic mechanisms.
-
Directory of Open Access Journals (Sweden)
Paul Kussmaul
2008-04-01
Full Text Available In the early phase of translation studies in Germany, contrastive linguistics played a major role. I shall briefly describe this approach so that the functional approach will become clearer by contrast. Influenced by the representatives of stylistique comparée, Vinay/Darbelnet (1968 Wolfram Wilss, for instance, in his early work (1971, 1977 makes frequent use of the notion transposition (German “Ausdrucksverschiebung“, cf. also Catford’s (1965 term shift. As a whole, of course, Wilss’ work has a much broader scope. More recently, he has investigated the role of cognition (1988 and the various factors in translator behaviour (1996. Nevertheless, transposition is still a very important and useful notion in describing the translation process. The need for transpositions arises when there is no possibility of formal one-to-one correspondence between source and target-language structures. The basic idea is that whenever there is a need for transposition, we are faced with a translation problem. In the early phase of translation studies in Germany, contrastive linguistics played a major role. I shall briefly describe this approach so that the functional approach will become clearer by contrast. Influenced by the representatives of stylistique comparée, Vinay/Darbelnet (1968 Wolfram Wilss, for instance, in his early work (1971, 1977 makes frequent use of the notion transposition (German “Ausdrucksverschiebung“, cf. also Catford’s (1965 term shift. As a whole, of course, Wilss’ work has a much broader scope. More recently, he has investigated the role of cognition (1988 and the various factors in translator behaviour (1996. Nevertheless, transposition is still a very important and useful notion in describing the translation process. The need for transpositions arises when there is no possibility of formal one-to-one correspondence between source and target-language structures. The basic idea is that whenever there is a need for
-
International Nuclear Information System (INIS)
Schillo, R. Sandra; Isabelle, Diane A.; Shakiba, Abtin
2017-01-01
The field of renewable energy policy is inherently complex due to the long-term impacts of its policies, the broad range of potential stakeholders, the intricacy of scientific, engineering and technological developments, and the interplay of complex policy mixes that may result in unintended consequences. Quality Function Deployment (QFD) provides a systematic consideration of all relevant stakeholders, a rigorous analysis of the needs of stakeholders, and a prioritization of design features based on stakeholders needs. We build on QFD combined with Analytical Hierarchy Process (AHP) to develop a novel method applied to the area of advanced biofuel policies. This Multi-Stakeholder Policy QFD (MSP QFD) provides a systematic approach to capture the voice of the stakeholders and align it with the broad range of potential advanced biofuels policies. To account for the policy environment, the MSP QFD utilizes a novel approach to stakeholder importance weights. This MSP QFD adds to the literature as it permits the analysis of the broad range of relevant national policies with regards to the development of advanced biofuels, as compared to more narrowly focused typical QFD applications. It also allows policy developers to gain additional insights into the perceived impacts of policies, as well as international comparisons. - Highlights: • Advanced biofuels are mostly still in research and early commercialization stages. • Government policies are expected to support biofuels stakeholders in market entry. • A Multi-Stakeholder Policy QFD (MSP QFD) links biofuels policies with stakeholders. • MSP QFD employs novel stakeholder weights method. • The case of advanced biofuels in Canada shows comparative importance of policies.
-
Robert D. Davic
2003-01-01
The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups ...
-
Directory of Open Access Journals (Sweden)
Tine N Vinther
Full Text Available An ingenious system evolved to facilitate insulin binding to the insulin receptor as a monomer and at the same time ensure sufficient stability of insulin during storage. Insulin dimer is the cornerstone of this system. Insulin dimer is relatively weak, which ensures dissociation into monomers in the circulation, and it is stabilized by hexamer formation in the presence of zinc ions during storage in the pancreatic β-cell. Due to the transient nature of insulin dimer, direct investigation of this important form is inherently difficult. To address the relationship between insulin oligomerization and insulin stability and function, we engineered a covalently linked insulin dimer in which two monomers were linked by a disulfide bond. The structure of this covalent dimer was identical to the self-association dimer of human insulin. Importantly, this covalent dimer was capable of further oligomerization to form the structural equivalent of the classical hexamer. The covalently linked dimer neither bound to the insulin receptor, nor induced a metabolic response in vitro. However, it was extremely thermodynamically stable and did not form amyloid fibrils when subjected to mechanical stress, underlining the importance of oligomerization for insulin stability.
-
Identifying Similarities in Cognitive Subtest Functional Requirements: An Empirical Approach
Frisby, Craig L.; Parkin, Jason R.
2007-01-01
In the cognitive test interpretation literature, a Rational/Intuitive, Indirect Empirical, or Combined approach is typically used to construct conceptual taxonomies of the functional (behavioral) similarities between subtests. To address shortcomings of these approaches, the functional requirements for 49 subtests from six individually…
-
Snyder, D
2002-01-01
A straightforward explanation of fundamental tenets of quantum mechanics concerning the wave function results in the thesis that the quantum mechanical wave function is a link between human cognition and the physical world. The reticence on the part of physicists to adopt this thesis is discussed. A comparison is made to the behaviorists' consideration of mind, and the historical roots of how the problem concerning the quantum mechanical wave function arose are discussed. The basis for an empirical demonstration that the wave function is a link between human cognition and the physical world is provided through developing an experiment using methodology from psychology and physics. Based on research in psychology and physics that relied on this methodology, it is likely that Einstein, Podolsky, and Rosen's theoretical result that mutually exclusive wave functions can simultaneously apply to the same concrete physical circumstances can be implemented on an empirical level.
-
Novel covalently linked insulin dimer engineered to investigate the function of insulin dimerization
DEFF Research Database (Denmark)
Vinther, Tine N.; Norrman, Mathias; Strauss, Holger M.
2012-01-01
An ingenious system evolved to facilitate insulin binding to the insulin receptor as a monomer and at the same time ensure sufficient stability of insulin during storage. Insulin dimer is the cornerstone of this system. Insulin dimer is relatively weak, which ensures dissociation into monomers...... in the circulation, and it is stabilized by hexamer formation in the presence of zinc ions during storage in the pancreatic ß-cell. Due to the transient nature of insulin dimer, direct investigation of this important form is inherently difficult. To address the relationship between insulin oligomerization...... and insulin stability and function, we engineered a covalently linked insulin dimer in which two monomers were linked by a disulfide bond. The structure of this covalent dimer was identical to the self-association dimer of human insulin. Importantly, this covalent dimer was capable of further oligomerization...
-
A global analysis approach for investigating structural resilience in urban drainage systems.
Mugume, Seith N; Gomez, Diego E; Fu, Guangtao; Farmani, Raziyeh; Butler, David
2015-09-15
Building resilience in urban drainage systems requires consideration of a wide range of threats that contribute to urban flooding. Existing hydraulic reliability based approaches have focused on quantifying functional failure caused by extreme rainfall or increase in dry weather flows that lead to hydraulic overloading of the system. Such approaches however, do not fully explore the full system failure scenario space due to exclusion of crucial threats such as equipment malfunction, pipe collapse and blockage that can also lead to urban flooding. In this research, a new analytical approach based on global resilience analysis is investigated and applied to systematically evaluate the performance of an urban drainage system when subjected to a wide range of structural failure scenarios resulting from random cumulative link failure. Link failure envelopes, which represent the resulting loss of system functionality (impacts) are determined by computing the upper and lower limits of the simulation results for total flood volume (failure magnitude) and average flood duration (failure duration) at each link failure level. A new resilience index that combines the failure magnitude and duration into a single metric is applied to quantify system residual functionality at each considered link failure level. With this approach, resilience has been tested and characterised for an existing urban drainage system in Kampala city, Uganda. In addition, the effectiveness of potential adaptation strategies in enhancing its resilience to cumulative link failure has been tested. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
-
Link prediction boosted psychiatry disorder classification for functional connectivity network
Li, Weiwei; Mei, Xue; Wang, Hao; Zhou, Yu; Huang, Jiashuang
2017-02-01
Functional connectivity network (FCN) is an effective tool in psychiatry disorders classification, and represents cross-correlation of the regional blood oxygenation level dependent signal. However, FCN is often incomplete for suffering from missing and spurious edges. To accurate classify psychiatry disorders and health control with the incomplete FCN, we first `repair' the FCN with link prediction, and then exact the clustering coefficients as features to build a weak classifier for every FCN. Finally, we apply a boosting algorithm to combine these weak classifiers for improving classification accuracy. Our method tested by three datasets of psychiatry disorder, including Alzheimer's Disease, Schizophrenia and Attention Deficit Hyperactivity Disorder. The experimental results show our method not only significantly improves the classification accuracy, but also efficiently reconstructs the incomplete FCN.
-
A semantic-based approach for querying linked data using natural language
Paredes-Valverde, Mario André s; Valencia-Garcí a, Rafael; Rodriguez-Garcia, Miguel Angel; Colomo-Palacios, Ricardo; Alor-Herná ndez, Giner
2016-01-01
The semantic Web aims to provide to Web information with a well-defined meaning and make it understandable not only by humans but also by computers, thus allowing the automation, integration and reuse of high-quality information across different applications. However, current information retrieval mechanisms for semantic knowledge bases are intended to be only used by expert users. In this work, we propose a natural language interface that allows non-expert users the access to this kind of information through formulating queries in natural language. The present approach uses a domain-independent ontology model to represent the question's structure and context. Also, this model allows determination of the answer type expected by the user based on a proposed question classification. To prove the effectiveness of our approach, we have conducted an evaluation in the music domain using LinkedBrainz, an effort to provide the MusicBrainz information as structured data on the Web by means of Semantic Web technologies. Our proposal obtained encouraging results based on the F-measure metric, ranging from 0.74 to 0.82 for a corpus of questions generated by a group of real-world end users. © The Author(s) 2015.
-
A semantic-based approach for querying linked data using natural language
Paredes-Valverde, Mario Andrés
2016-01-11
The semantic Web aims to provide to Web information with a well-defined meaning and make it understandable not only by humans but also by computers, thus allowing the automation, integration and reuse of high-quality information across different applications. However, current information retrieval mechanisms for semantic knowledge bases are intended to be only used by expert users. In this work, we propose a natural language interface that allows non-expert users the access to this kind of information through formulating queries in natural language. The present approach uses a domain-independent ontology model to represent the question\\'s structure and context. Also, this model allows determination of the answer type expected by the user based on a proposed question classification. To prove the effectiveness of our approach, we have conducted an evaluation in the music domain using LinkedBrainz, an effort to provide the MusicBrainz information as structured data on the Web by means of Semantic Web technologies. Our proposal obtained encouraging results based on the F-measure metric, ranging from 0.74 to 0.82 for a corpus of questions generated by a group of real-world end users. © The Author(s) 2015.
-
Stanton, Neville A; Harvey, Catherine
2017-02-01
Risk assessments in Sociotechnical Systems (STS) tend to be based on error taxonomies, yet the term 'human error' does not sit easily with STS theories and concepts. A new break-link approach was proposed as an alternative risk assessment paradigm to reveal the effect of information communication failures between agents and tasks on the entire STS. A case study of the training of a Royal Navy crew detecting a low flying Hawk (simulating a sea-skimming missile) is presented using EAST to model the Hawk-Frigate STS in terms of social, information and task networks. By breaking 19 social links and 12 task links, 137 potential risks were identified. Discoveries included revealing the effect of risk moving around the system; reducing the risks to the Hawk increased the risks to the Frigate. Future research should examine the effects of compounded information communication failures on STS performance. Practitioner Summary: The paper presents a step-by-step walk-through of EAST to show how it can be used for risk assessment in sociotechnical systems. The 'broken-links' method takes a systemic, rather than taxonomic, approach to identify information communication failures in social and task networks.
-
Link overlap, viability, and mutual percolation in multiplex networks
International Nuclear Information System (INIS)
Min, Byungjoon; Lee, Sangchul; Lee, Kyu-Min; Goh, K.-I.
2015-01-01
Many real-world complex systems are best modeled by multiplex networks. The multiplexity has proved to have broad impact on the system’s structure and function. Most theoretical studies on multiplex networks to date, however, have largely ignored the effect of the link overlap across layers despite strong empirical evidences for its significance. In this article, we investigate the effect of the link overlap in the viability of multiplex networks, both analytically and numerically. After a short recap of the original multiplex viability study, the distinctive role of overlapping links in viability and mutual connectivity is emphasized and exploited for setting up a proper analytic framework. A rich phase diagram for viability is obtained and greatly diversified patterns of hysteretic behavior in viability are observed in the presence of link overlap. Mutual percolation with link overlap is revisited as a limit of multiplex viability problem, and the controversy between existing results is clarified. The distinctive role of overlapping links is further demonstrated by the different responses of networks under random removals of overlapping and non-overlapping links, respectively, as well as under several link-removal strategies. Our results show that the link overlap facilitates the viability and mutual percolation; at the same time, the presence of link overlap poses a challenge in analytical approaches to the problem
-
An approach to the structure function for nucleon
International Nuclear Information System (INIS)
Long Ming
1986-01-01
The structure function for nucleon is discussed by using the method given in a previous paper. The formula are compared with the experimental data from low Q 2 to high Q 2 . The results show that the way that the structure function for nucleon can be obtained from the hadronic wavefunction is a possible approach of investigating structure functions for hadron
-
Conserved properties of Drosophila Insomniac link sleep regulation and synaptic function.
Li, Qiuling; Kellner, David A; Hatch, Hayden A M; Yumita, Tomohiro; Sanchez, Sandrine; Machold, Robert P; Frank, C Andrew; Stavropoulos, Nicholas
2017-05-01
Sleep is an ancient animal behavior that is regulated similarly in species ranging from flies to humans. Various genes that regulate sleep have been identified in invertebrates, but whether the functions of these genes are conserved in mammals remains poorly explored. Drosophila insomniac (inc) mutants exhibit severely shortened and fragmented sleep. Inc protein physically associates with the Cullin-3 (Cul3) ubiquitin ligase, and neuronal depletion of Inc or Cul3 strongly curtails sleep, suggesting that Inc is a Cul3 adaptor that directs the ubiquitination of neuronal substrates that impact sleep. Three proteins similar to Inc exist in vertebrates-KCTD2, KCTD5, and KCTD17-but are uncharacterized within the nervous system and their functional conservation with Inc has not been addressed. Here we show that Inc and its mouse orthologs exhibit striking biochemical and functional interchangeability within Cul3 complexes. Remarkably, KCTD2 and KCTD5 restore sleep to inc mutants, indicating that they can substitute for Inc in vivo and engage its neuronal targets relevant to sleep. Inc and its orthologs localize similarly within fly and mammalian neurons and can traffic to synapses, suggesting that their substrates may include synaptic proteins. Consistent with such a mechanism, inc mutants exhibit defects in synaptic structure and physiology, indicating that Inc is essential for both sleep and synaptic function. Our findings reveal that molecular functions of Inc are conserved through ~600 million years of evolution and support the hypothesis that Inc and its orthologs participate in an evolutionarily conserved ubiquitination pathway that links synaptic function and sleep regulation.
-
Materializing the web of linked data
Konstantinou, Nikolaos
2015-01-01
This book explains the Linked Data domain by adopting a bottom-up approach: it introduces the fundamental Semantic Web technologies and building blocks, which are then combined into methodologies and end-to-end examples for publishing datasets as Linked Data, and use cases that harness scholarly information and sensor data. It presents how Linked Data is used for web-scale data integration, information management and search. Special emphasis is given to the publication of Linked Data from relational databases as well as from real-time sensor data streams. The authors also trace the transformation from the document-based World Wide Web into a Web of Data. Materializing the Web of Linked Data is addressed to researchers and professionals studying software technologies, tools and approaches that drive the Linked Data ecosystem, and the Web in general.
-
A density functional approach to ferrogels
Cremer, P.; Heinen, M.; Menzel, A. M.; Löwen, H.
2017-07-01
Ferrogels consist of magnetic colloidal particles embedded in an elastic polymer matrix. As a consequence, their structural and rheological properties are governed by a competition between magnetic particle-particle interactions and mechanical matrix elasticity. Typically, the particles are permanently fixed within the matrix, which makes them distinguishable by their positions. Over time, particle neighbors do not change due to the fixation by the matrix. Here we present a classical density functional approach for such ferrogels. We map the elastic matrix-induced interactions between neighboring colloidal particles distinguishable by their positions onto effective pairwise interactions between indistinguishable particles similar to a ‘pairwise pseudopotential’. Using Monte-Carlo computer simulations, we demonstrate for one-dimensional dipole-spring models of ferrogels that this mapping is justified. We then use the pseudopotential as an input into classical density functional theory of inhomogeneous fluids and predict the bulk elastic modulus of the ferrogel under various conditions. In addition, we propose the use of an ‘external pseudopotential’ when one switches from the viewpoint of a one-dimensional dipole-spring object to a one-dimensional chain embedded in an infinitely extended bulk matrix. Our mapping approach paves the way to describe various inhomogeneous situations of ferrogels using classical density functional concepts of inhomogeneous fluids.
-
Kanoh, Naoki; Asami, Aya; Kawatani, Makoto; Honda, Kaori; Kumashiro, Saori; Takayama, Hiroshi; Simizu, Siro; Amemiya, Tomoyuki; Kondoh, Yasumitsu; Hatakeyama, Satoru; Tsuganezawa, Keiko; Utata, Rei; Tanaka, Akiko; Yokoyama, Shigeyuki; Tashiro, Hideo; Osada, Hiroyuki
2006-12-18
We have developed a unique photo-cross-linking approach for immobilizing a variety of small molecules in a functional-group-independent manner. Our approach depends on the reactivity of the carbene species generated from trifluoromethylaryldiazirine upon UV irradiation. It was demonstrated in model experiments that the photogenerated carbenes were able to react with every small molecule tested, and they produced multiple conjugates in most cases. It was also found in on-array immobilization experiments that various small molecules were immobilized, and the immobilized small molecules retained their ability to interact with their binding proteins. With this approach, photo-cross-linked microarrays of about 2000 natural products and drugs were constructed. This photo-cross-linked microarray format was found to be useful not merely for ligand screening but also to study the structure-activity relationship, that is, the relationship between the structural motif (or pharmacophore) found in small molecules and its binding affinity toward a protein, by taking advantage of the nonselective nature of the photo-cross-linking process.
-
A Constructive Sharp Approach to Functional Quantization of Stochastic Processes
Junglen, Stefan; Luschgy, Harald
2010-01-01
We present a constructive approach to the functional quantization problem of stochastic processes, with an emphasis on Gaussian processes. The approach is constructive, since we reduce the infinite-dimensional functional quantization problem to a finite-dimensional quantization problem that can be solved numerically. Our approach achieves the sharp rate of the minimal quantization error and can be used to quantize the path space for Gaussian processes and also, for example, Lévy processes.
-
Estimating variability in functional images using a synthetic resampling approach
International Nuclear Information System (INIS)
Maitra, R.; O'Sullivan, F.
1996-01-01
Functional imaging of biologic parameters like in vivo tissue metabolism is made possible by Positron Emission Tomography (PET). Many techniques, such as mixture analysis, have been suggested for extracting such images from dynamic sequences of reconstructed PET scans. Methods for assessing the variability in these functional images are of scientific interest. The nonlinearity of the methods used in the mixture analysis approach makes analytic formulae for estimating variability intractable. The usual resampling approach is infeasible because of the prohibitive computational effort in simulating a number of sinogram. datasets, applying image reconstruction, and generating parametric images for each replication. Here we introduce an approach that approximates the distribution of the reconstructed PET images by a Gaussian random field and generates synthetic realizations in the imaging domain. This eliminates the reconstruction steps in generating each simulated functional image and is therefore practical. Results of experiments done to evaluate the approach on a model one-dimensional problem are very encouraging. Post-processing of the estimated variances is seen to improve the accuracy of the estimation method. Mixture analysis is used to estimate functional images; however, the suggested approach is general enough to extend to other parametric imaging methods
-
Krüger, Dennis M; Rathi, Prakash Chandra; Pfleger, Christopher; Gohlke, Holger
2013-07-01
The Constraint Network Analysis (CNA) web server provides a user-friendly interface to the CNA approach developed in our laboratory for linking results from rigidity analyses to biologically relevant characteristics of a biomolecular structure. The CNA web server provides a refined modeling of thermal unfolding simulations that considers the temperature dependence of hydrophobic tethers and computes a set of global and local indices for quantifying biomacromolecular stability. From the global indices, phase transition points are identified where the structure switches from a rigid to a floppy state; these phase transition points can be related to a protein's (thermo-)stability. Structural weak spots (unfolding nuclei) are automatically identified, too; this knowledge can be exploited in data-driven protein engineering. The local indices are useful in linking flexibility and function and to understand the impact of ligand binding on protein flexibility. The CNA web server robustly handles small-molecule ligands in general. To overcome issues of sensitivity with respect to the input structure, the CNA web server allows performing two ensemble-based variants of thermal unfolding simulations. The web server output is provided as raw data, plots and/or Jmol representations. The CNA web server, accessible at http://cpclab.uni-duesseldorf.de/cna or http://www.cnanalysis.de, is free and open to all users with no login requirement.
-
De-masking oxytocin-deficiency in craniopharyngioma and assessing its link with affective function.
Gebert, Dorothea; Auer, Matthias K; Stieg, Mareike R; Freitag, Martin T; Lahne, Madlén; Fuss, Johannes; Schilbach, Katharina; Schopohl, Jochen; Stalla, Günter K; Kopczak, Anna
2018-02-01
Despite the high prevalence of panhypopituitarism and diabetes insipidus in patients with craniopharyngioma (CP), little is known about the functioning of the neuropeptide oxytocin in these patients. This is of special interest as tumor-associated lesions often impair sites critical for oxytocin production and release, and affective dysfunction in CP links with elsewhere reported prosocial, antidepressant and anxiolytic oxytocin effects. Using a prospective study-design, we tested whether oxytocin is reduced in CP-patients, and whether altered oxytocin levels account for affective and emotional dysfunction. 26 adult CP-patients and 26 healthy controls matched in sex and age underwent physical exercise, a stimulus previously shown to induce oxytocin release. Baseline and stimulated salivary oxytocin levels, as well as empathy, depression and anxiety scores were measured. Results showed that patients overall did not present with lower baseline oxytocin levels than controls (F[1,30]=0.21, p=0.649), but baseline oxytocin levels were indeed reduced in patients with hypothalamic damage, as assessed by MRI-based grading (F[2,9.79]=4.54, p=0.040). In response to exercise-induced stimulation, all CP-patients showed a blunted oxytocin-release compared to controls (F[1,30]=9.36, p=0.005). DI was not associated with oxytocin levels. Regarding affective function, unexpectedly, higher baseline oxytocin was related to higher trait anxiety (b=2.885, t(43)=2.421, p=0.020, CI[.478; 5.292]); the positive link with higher depression failed to reach statistical significance (b=1.928, t(43)=1.949, p=0.058, CI[-0.070; 3.927]). A blunted oxytocin-release was linked with higher state anxiety (b=-0.133, t(43)=-2.797, p=0.008, CI[-0.230; -0.037]). Empathy was not associated with oxytocin measures. In conclusion, we observed reduced baseline oxytocin levels only in CP-patients with hypothalamic damage. Exercise-induced stimulation de-masked an oxytocin-deficiency in all CP-patients. Baseline
-
Silva, Elena; Rosario, Fredrick J; Powell, Theresa L; Jansson, Thomas
2017-07-01
Folate deficiency has been linked to a wide range of disorders, including cancer, neural tube defects, and fetal growth restriction. Folate regulates cellular function mediated by its involvement in the synthesis of nucleotides, which are needed for DNA synthesis, and its function as a methyl donor, which is critical for DNA methylation. Here we review current data showing that folate sensing by mechanistic target of rapamycin (mTOR) constitutes a novel and distinct pathway by which folate modulates cell functions such as nutrient transport, protein synthesis, and mitochondrial respiration. The mTOR signaling pathway responds to growth factors and changes in nutrient availability to control cell growth, proliferation, and metabolism. mTOR exists in 2 complexes, mTOR complex (mTORC) 1 and mTORC2, which have distinct upstream regulators and downstream targets. Folate deficiency in pregnant mice caused a marked inhibition of mTORC1 and mTORC2 signaling in multiple maternal and fetal tissues, downregulation of placental amino acid transporters, and fetal growth restriction. In addition, folate deficiency in primary human trophoblast (PHT) cells resulted in inhibition of mTORC1 and mTORC2 signaling and decreased the activity of key amino acid transporters. Folate sensing by mTOR in PHT cells is independent of the accumulation of homocysteine and requires the proton-coupled folate transporter (PCFT; solute carrier 46A1). Furthermore, mTORC1 and mTORC2 regulate trophoblast folate uptake by modulating the cell surface expression of folate receptor α and the reduced folate carrier. These findings, which provide a novel link between folate availability and cell function, growth, and proliferation, may have broad biological significance given the critical role of folate in normal cell function and the multiple diseases that have been associated with decreased or excessive folate availability. Low maternal folate concentrations are linked to restricted fetal growth, and we
-
Combining Formal and Functional Approaches to Topic Structure
Zellers, Margaret; Post, Brechtje
2012-01-01
Fragmentation between formal and functional approaches to prosodic variation is an ongoing problem in linguistic research. In particular, the frameworks of the Phonetics of Talk-in-Interaction (PTI) and Empirical Phonology (EP) take very different theoretical and methodological approaches to this kind of variation. We argue that it is fruitful to…
-
Zeng, L.; Zhao, T. S.; Wei, L.; Zeng, Y. K.; Zhang, Z. H.
2016-11-01
It has recently been demonstrated that the use of anion exchange membranes (AEMs) in vanadium redox flow batteries (VRFBs) can reduce the migration of vanadium ions through the membrane due to the Donnan exclusion effect among the positively charged functional groups and vanadium ions. However, AEMs are plagued by low chemical stability in harsh chemical environments. Here we propose and fabricate a pyridinium-functionalized cross-linked AEM for VRFBs. The pyridinium-functionalized bromomethylated poly (2,6-dimethyl-1,4-phenylene oxide) exhibits a superior chemical stability as a result of the strengthened internal cross-linking networks and the chemical inertness of the polymer backbone. Therefore, the membrane exhibits littler decay in a harsh environment for 20 days during the course of an ex situ immersion test. A cycling test also demonstrates that the VRFB assembled with the membrane enable to retain 80% of the initial discharge capacity over 537 cycles with a capacity decay rate of 0.037% cycle-1. Meanwhile, the membrane also shows a low vanadium permeability and a reasonably high conductivity in supporting electrolytes. Hence, all the measurements and performance tests reported in this work suggest that the membrane is a promising AEM for redox flow batteries to achieve excellent cycling stability and superior cell performance.
-
LinkED: A Novel Methodology for Publishing Linked Enterprise Data
Directory of Open Access Journals (Sweden)
Shreyas Suresh Rao
2017-01-01
Full Text Available Semantic Web technologies have redefined and strengthened the Enterprise-Web interoperability over the last decade. Linked Open Data (LOD refers to a set of best practices that empower enterprises to publish and interlink their data using existing ontologies on the World Wide Web. Current research in LOD focuses on expert search, the creation of unified information space and augmentation of core data from an enterprise context. However, existing approaches for publication of enterprise data as LOD are domain-specific, ad-hoc and suffer from lack of uniform representation across domains. The paper proposes a novel methodology called LinkED that contributes towards LOD literature in two ways: (a streamlines the publishing process through five stages of cleaning, triplification, interlinking, storage and visualization; (b addresses the latest challenges in LOD publication, namely: inadequate links, inconsistencies in the quality of the dataset and replicability of the LOD publication process. Further, the methodology is demonstrated via the publication of digital repository data as LOD in a university setting, which is evaluated based on two semantic standards: Five-Star model and data quality metrics. Overall, the paper provides a generic LOD publication process that is applicable across various domains such as healthcare, e-governance, banking, and tourism, to name a few.
-
Directory of Open Access Journals (Sweden)
Yun Xiao
Full Text Available Accumulating evidence shows a tight link between inflammation and cancer. However, comprehensive identification of pivotal transcription factors (i.e., core TFs mediating the dysregulated links remains challenging, mainly due to a lack of samples that can effectively reflect the connections between inflammation and tumorigenesis. Here, we constructed a series of TF-mediated regulatory networks from a large compendium of expression profiling of normal colonic tissues, inflammatory bowel diseases (IBDs and colorectal cancer (CRC, which contains 1201 samples in total, and then proposed a network-based approach to characterize potential links bridging inflammation and cancer. For this purpose, we computed significantly dysregulated relationships between inflammation and their linked cancer networks, and then 24 core TFs with their dysregulated genes were identified. Collectively, our approach provides us with quite important insight into inflammation-associated tumorigenesis in colorectal cancer, which could also be applied to identify functionally dysregulated relationships mediating the links between other different disease phenotypes.
-
Graça, Márlon B; Morais, José W; Franklin, Elizabeth; Pequeno, Pedro A C L; Souza, Jorge L P; Bueno, Anderson Saldanha
2016-04-01
This study investigated the spatial distribution of an Amazonian fruit-feeding butterfly assemblage by linking species taxonomic and functional approaches. We hypothesized that: 1) vegetation richness (i.e., resources) and abundance of insectivorous birds (i.e., predators) should drive changes in butterfly taxonomic composition, 2) larval diet breadth should decrease with increase of plant species richness, 3) small-sized adults should be favored by higher abundance of birds, and 4) communities with eyespot markings should be able to exploit areas with higher predation pressure. Fruit-feeding butterflies were sampled with bait traps and insect nets across 25 km(2) of an Amazonian ombrophilous forest in Brazil. We measured larval diet breadth, adult body size, and wing marking of all butterflies. Our results showed that plant species richness explained most of the variation in butterfly taxonomic turnover. Also, community average diet breadth decreased with increase of plant species richness, which supports our expectations. In contrast, community average body size increased with the abundance of birds, refuting our hypothesis. We detected no influence of environmental gradients on the occurrence of species with eyespot markings. The association between butterfly taxonomic and functional composition points to a mediator role of the functional traits in the environmental filtering of butterflies. The incorporation of the functional approach into the analyses allowed for the detection of relationships that were not observed using a strictly taxonomic perspective and provided an extra insight into comprehending the potential adaptive strategies of butterflies. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
-
The integration of weighted human gene association networks based on link prediction.
Yang, Jian; Yang, Tinghong; Wu, Duzhi; Lin, Limei; Yang, Fan; Zhao, Jing
2017-01-31
Physical and functional interplays between genes or proteins have important biological meaning for cellular functions. Some efforts have been made to construct weighted gene association meta-networks by integrating multiple biological resources, where the weight indicates the confidence of the interaction. However, it is found that these existing human gene association networks share only quite limited overlapped interactions, suggesting their incompleteness and noise. Here we proposed a workflow to construct a weighted human gene association network using information of six existing networks, including two weighted specific PPI networks and four gene association meta-networks. We applied link prediction algorithm to predict possible missing links of the networks, cross-validation approach to refine each network and finally integrated the refined networks to get the final integrated network. The common information among the refined networks increases notably, suggesting their higher reliability. Our final integrated network owns much more links than most of the original networks, meanwhile its links still keep high functional relevance. Being used as background network in a case study of disease gene prediction, the final integrated network presents good performance, implying its reliability and application significance. Our workflow could be insightful for integrating and refining existing gene association data.
-
Opening Up Climate Research: A Linked Data Approach to Publishing Data Provenance
Directory of Open Access Journals (Sweden)
Arif Shaon
2012-03-01
Full Text Available Traditionally, the formal scientific output in most fields of natural science has been limited to peer-reviewed academic journal publications, with less attention paid to the chain of intermediate data results and their associated metadata, including provenance. In effect, this has constrained the representation and verification of the data provenance to the confines of the related publications. Detailed knowledge of a dataset’s provenance is essential to establish the pedigree of the data for its effective re-use, and to avoid redundant re-enactment of the experiment or computation involved. It is increasingly important for open-access data to determine their authenticity and quality, especially considering the growing volumes of datasets appearing in the public domain. To address these issues, we present an approach that combines the Digital Object Identifier (DOI – a widely adopted citation technique – with existing, widely adopted climate science data standards to formally publish detailed provenance of a climate research dataset as an associated scientific workflow. This is integrated with linked-data compliant data re-use standards (e.g. OAI-ORE to enable a seamless link between a publication and the complete trail of lineage of the corresponding dataset, including the dataset itself.
-
Hashimoto, Ryu-Ichiro; Itahashi, Takashi; Okada, Rieko; Hasegawa, Sayaka; Tani, Masayuki; Kato, Nobumasa; Mimura, Masaru
2018-01-01
Abnormalities in functional brain networks in schizophrenia have been studied by examining intrinsic and extrinsic brain activity under various experimental paradigms. However, the identified patterns of abnormal functional connectivity (FC) vary depending on the adopted paradigms. Thus, it is unclear whether and how these patterns are inter-related. In order to assess relationships between abnormal patterns of FC during intrinsic activity and those during extrinsic activity, we adopted a data-fusion approach and applied partial least square (PLS) analyses to FC datasets from 25 patients with chronic schizophrenia and 25 age- and sex-matched normal controls. For the input to the PLS analyses, we generated a pair of FC maps during the resting state (REST) and the auditory deviance response (ADR) from each participant using the common seed region in the left middle temporal gyrus, which is a focus of activity associated with auditory verbal hallucinations (AVHs). PLS correlation (PLS-C) analysis revealed that patients with schizophrenia have significantly lower loadings of a component containing positive FCs in default-mode network regions during REST and a component containing positive FCs in the auditory and attention-related networks during ADR. Specifically, loadings of the REST component were significantly correlated with the severities of positive symptoms and AVH in patients with schizophrenia. The co-occurrence of such altered FC patterns during REST and ADR was replicated using PLS regression, wherein FC patterns during REST are modeled to predict patterns during ADR. These findings provide an integrative understanding of altered FCs during intrinsic and extrinsic activity underlying core schizophrenia symptoms.
-
Developmental imaging genetics: linking dopamine function to adolescent behavior.
Padmanabhan, Aarthi; Luna, Beatriz
2014-08-01
Adolescence is a period of development characterized by numerous neurobiological changes that significantly influence behavior and brain function. Adolescence is of particular interest due to the alarming statistics indicating that mortality rates increase two to three-fold during this time compared to childhood, due largely to a peak in risk-taking behaviors resulting from increased impulsivity and sensation seeking. Furthermore, there exists large unexplained variability in these behaviors that are in part mediated by biological factors. Recent advances in molecular genetics and functional neuroimaging have provided a unique and exciting opportunity to non-invasively study the influence of genetic factors on brain function in humans. While genes do not code for specific behaviors, they do determine the structure and function of proteins that are essential to the neuronal processes that underlie behavior. Therefore, studying the interaction of genotype with measures of brain function over development could shed light on critical time points when biologically mediated individual differences in complex behaviors emerge. Here we review animal and human literature examining the neurobiological basis of adolescent development related to dopamine neurotransmission. Dopamine is of critical importance because of (1) its role in cognitive and affective behaviors, (2) its role in the pathogenesis of major psychopathology, and (3) the protracted development of dopamine signaling pathways over adolescence. We will then focus on current research examining the role of dopamine-related genes on brain function. We propose the use of imaging genetics to examine the influence of genetically mediated dopamine variability on brain function during adolescence, keeping in mind the limitations of this approach. Copyright © 2014 Elsevier Inc. All rights reserved.
-
Mechanical Strength Improvements of Carbon Nanotube Threads through Epoxy Cross-Linking
Directory of Open Access Journals (Sweden)
Qingyue Yu
2016-01-01
Full Text Available Individual Carbon Nanotubes (CNTs have a great mechanical strength that needs to be transferred into macroscopic fiber assemblies. One approach to improve the mechanical strength of the CNT assemblies is by creating covalent bonding among their individual CNT building blocks. Chemical cross-linking of multiwall CNTs (MWCNTs within the fiber has significantly improved the strength of MWCNT thread. Results reported in this work show that the cross-linked thread had a tensile strength six times greater than the strength of its control counterpart, a pristine MWCNT thread (1192 MPa and 194 MPa, respectively. Additionally, electrical conductivity changes were observed, revealing 2123.40 S·cm−1 for cross-linked thread, and 3984.26 S·cm−1 for pristine CNT thread. Characterization suggests that the obtained high tensile strength is due to the cross-linking reaction of amine groups from ethylenediamine plasma-functionalized CNT with the epoxy groups of the cross-linking agent, 4,4-methylenebis(N,N-diglycidylaniline.
-
Problems in the links between scattering data and interaction potentials
Energy Technology Data Exchange (ETDEWEB)
Amos, K.
1995-10-01
The scattering function is of paramount importance in any approaches by which quantitative information on the interaction between colliding quantal systems of nuclear, atomic or molecular type, may be sought from measured, elastic scattering data. Therein there are two possible spectral parameters, the energy and the angular momentum. Most experimental results suggest use of fixed energy and variable angular momentum schemes. Such fixed energy data and their analyses are the subject of this report, with particular emphasis placed upon the problems of the link between data and the scattering function. 18 figs.
-
Problems in the links between scattering data and interaction potentials
International Nuclear Information System (INIS)
Amos, K.
1995-01-01
The scattering function is of paramount importance in any approaches by which quantitative information on the interaction between colliding quantal systems of nuclear, atomic or molecular type, may be sought from measured, elastic scattering data. Therein there are two possible spectral parameters, the energy and the angular momentum. Most experimental results suggest use of fixed energy and variable angular momentum schemes. Such fixed energy data and their analyses are the subject of this report, with particular emphasis placed upon the problems of the link between data and the scattering function. 18 figs
-
Directory of Open Access Journals (Sweden)
Marcos Hernández Suárez
2016-11-01
Full Text Available Tomatoes have been described as a functional food because of their particular composition of different bioactive compounds. In this study, the proximate composition, minerals and trace elements, and antioxidant compounds were determined in two tomato cultivars (Mariana and Dunkan that were grown in Gran Canaria (Spain either conventionally or hydroponically. Although compositional data of this type require being subjected to the specific statistical techniques of compositional analysis, this approach has not usually been considered in this context. In the present case, a compositional Mann–Whitney U test of the data showed significant differences for each factor (cultivar and cultivation system in several of the compositional variables studied. For the differences between cultivars, these parameters were the protein, Mg, lycopene, ascorbic acid, citric acid, and fumaric acid contents. For the differences between cultivation systems, they were mainly those of the mineral and trace elements group. Although one-year data are insufficient to make clear relationship among compounds because more repetitions in several localities and years are necessary, the compositional HJ-biplot (in which the links provide estimates of the linear relationship among variables results agreed with other scientific results about linear relationship among some compounds analyzed.
-
On the link between oil and commodity prices: a panel VAR approach
International Nuclear Information System (INIS)
Bremond, Vincent; Hache, Emmanuel; Joets, Marc
2013-12-01
The aim of this paper is to study the relationships between the price of oil and a large dataset of commodity prices, relying on panel data settings. Using second generation panel co-integration tests, our findings show that the WTI and commodity prices are not linked in the long term. Nevertheless, considering our results in causality tests, we show that short-run relations exist, mainly from the price of crude oil to commodity prices. We thus implement a panel VAR estimation with an impulse response function analysis. Two main conclusions emerge: (i) fast co-movements are highlighted, while (ii) market efficiency is emphasized. (authors)
-
Passant, Alexandre; Laublet, Philippe; Breslin, John G.; Decker, Stefan
During the past few years, various organisations embraced the Enterprise 2.0 paradigms, providing their employees with new means to enhance collaboration and knowledge sharing in the workplace. However, while tools such as blogs, wikis, and principles like free-tagging or content syndication allow user-generated content to be more easily created and shared in the enterprise, in spite of some social issues, these new practices lead to various problems in terms of knowledge management. In this chapter, we provide an approach based on Semantic Web and Linked Data technologies for (1) integrating heterogeneous data from distinct Enterprise 2.0 applications, and (2) bridging the gap between raw text and machine-readable Linked Data. We discuss the theoretical background of our proposal as well as a practical case-study in enterprise, focusing on the various add-ons that have been provided to the original information system, as well as presenting how public Linked Open Data from the Web can be used to enhance existing Enterprise 2.0 ecosystems.
-
Sacco, William P; Bykowski, Cathy A; Mayhew, Laura L
2013-03-01
Among people with diabetes, depression is more common and is associated with greater morbidity and mortality. A better understanding of mechanisms underlying the link between poor health and depression is needed. Pain and functional impairment may account for the effect of poor health on depression in diabetes. The purpose of the study was to examine whether pain and functional impairment mediate the association between diabetes-related medical symptoms and depression in type 2 diabetes. Adults diagnosed with type 2 diabetes (N = 77) completed the following measures: Patient Health Questionnaire (PHQ), Diabetes Symptom Checklist (DSC), and Medical Outcomes Study 12-item Short-Form Health Survey (SF-12). Body mass index (BMI) was computed using height and weight data from medical records. Mediation and linear regression analyses were conducted. Pain and functional impairment made significant, independent contributions to depression. Functional impairment mediated the link between diabetes-related medical symptoms and depression. Pain mediated the association between higher BMI and depression. Pain and functional impairment appear to play important, independent roles in depression in type 2 diabetes. Mediation analyses suggest the following: 1. diabetes-related medical problems increase functional impairment, which in turn leads to greater depression; and 2. the burden of carrying greater body mass (higher BMI) increases pain, which leads to increased depression.
-
On the functional integral approach in quantum statistics. 1. Some approximations
International Nuclear Information System (INIS)
Dai Xianxi.
1990-08-01
In this paper the susceptibility of a Kondo system in a fairly wide temperature region is calculated in the first harmonic approximation in a functional integral approach. The comparison with that of the renormalization group theory shows that in this region the two results agree quite well. The expansion of the partition function with infinite independent harmonics for the Anderson model is studied. Some symmetry relations are generalized. It is a challenging problem to develop a functional integral approach including diagram analysis, mixed mode effects and some exact relations in the Anderson system proved in the functional integral approach. These topics will be discussed in the next paper. (author). 22 refs, 1 fig
-
An evolutionary computation approach to examine functional brain plasticity
Directory of Open Access Journals (Sweden)
Arnab eRoy
2016-04-01
Full Text Available One common research goal in systems neurosciences is to understand how the functional relationship between a pair of regions of interest (ROIs evolves over time. Examining neural connectivity in this way is well-suited for the study of developmental processes, learning, and even in recovery or treatment designs in response to injury. For most fMRI based studies, the strength of the functional relationship between two ROIs is defined as the correlation between the average signal representing each region. The drawback to this approach is that much information is lost due to averaging heterogeneous voxels, and therefore, the functional relationship between a ROI-pair that evolve at a spatial scale much finer than the ROIs remain undetected. To address this shortcoming, we introduce a novel evolutionary computation (EC based voxel-level procedure to examine functional plasticity between an investigator defined ROI-pair by simultaneously using subject-specific BOLD-fMRI data collected from two sessions seperated by finite duration of time. This data-driven procedure detects a sub-region composed of spatially connected voxels from each ROI (a so-called sub-regional-pair such that the pair shows a significant gain/loss of functional relationship strength across the two time points. The procedure is recursive and iteratively finds all statistically significant sub-regional-pairs within the ROIs. Using this approach, we examine functional plasticity between the default mode network (DMN and the executive control network (ECN during recovery from traumatic brain injury (TBI; the study includes 14 TBI and 12 healthy control subjects. We demonstrate that the EC based procedure is able to detect functional plasticity where a traditional averaging based approach fails. The subject-specific plasticity estimates obtained using the EC-procedure are highly consistent across multiple runs. Group-level analyses using these plasticity estimates showed an increase in
-
A new approach to the logistic function with some applications
Rzadkowski, Grzegorz; Głażewska, Iwona; Sawińska, Katarzyna
2014-01-01
In the present paper we propose a new approach to investigate the logistic function, commonly used in mathematical models in economics and management. The approach is based on indicating in a given time series, having a logistic trend, some characteristic points corresponding to zeroes of successive derivatives of the logistic function. We give also examples of application of this method.
-
Directory of Open Access Journals (Sweden)
T.Yu. Yuzvenko
2014-05-01
Full Text Available The article presents research findings of reduced thyroid function impact on the background of insulin resistance on the specific links of metabolism, structure and function of the heart. It is found that in thyroid dysfunction, the main nosological form of myocardial lesion in female patients without concomitant cardiovascular disease is the development of metabolic endocrine cardiomyopathy. Feature of cardiac lesion is the absence of cardiosclerotic, myocardial and ischemic processes in hypothyroidism. Obscure clinical symptoms of the heart both in apparent and subclinical hypothyroidism are detected. Features of clinical, instrumental and laboratory changes in female patients with impaired thyroid function are a trend to systolic blood pressure increase, the absence of significant dyslipidemia, dysglycemia, and cardiocytolysis and hepatocytolysis. Thyroid hormone deficiency is associated with increased myocardial repolarization heterogeneity: subclinical hypothyroidism is accompanied by violation of repolarization processes and the development of electrical heterogeneity of ventricular myocardium, and in the apparent hypothyroidism changes are more linked with the violation of the homogeneity of the electrical impulse to the atria.
-
Mechanistic links between gut microbial community dynamics, microbial functions and metabolic health
Ha, Connie WY; Lam, Yan Y; Holmes, Andrew J
2014-01-01
Gut microbes comprise a high density, biologically active community that lies at the interface of an animal with its nutritional environment. Consequently their activity profoundly influences many aspects of the physiology and metabolism of the host animal. A range of microbial structural components and metabolites directly interact with host intestinal cells and tissues to influence nutrient uptake and epithelial health. Endocrine, neuronal and lymphoid cells in the gut also integrate signals from these microbial factors to influence systemic responses. Dysregulation of these host-microbe interactions is now recognised as a major risk factor in the development of metabolic dysfunction. This is a two-way process and understanding the factors that tip host-microbiome homeostasis over to dysbiosis requires greater appreciation of the host feedbacks that contribute to regulation of microbial community composition. To date, numerous studies have employed taxonomic profiling approaches to explore the links between microbial composition and host outcomes (especially obesity and its comorbidities), but inconsistent host-microbe associations have been reported. Available data indicates multiple factors have contributed to discrepancies between studies. These include the high level of functional redundancy in host-microbiome interactions combined with individual variation in microbiome composition; differences in study design, diet composition and host system between studies; and inherent limitations to the resolution of rRNA-based community profiling. Accounting for these factors allows for recognition of the common microbial and host factors driving community composition and development of dysbiosis on high fat diets. New therapeutic intervention options are now emerging. PMID:25469018
-
Blaga, Monica; Van Yperen, N.W.
2008-01-01
The purpose of this study was to demonstrate that the positive link between task interest and performance attainment can he negatively affected by the pursuit of difficult performance-approach goals. This was tested in a sample of 60 undergraduate Students at a Dutch university, In line with
-
A longitudinal study of visual function in carriers of X-linked recessive retinitis pigmentosa.
Grover, S; Fishman, G A; Anderson, R J; Lindeman, M
2000-02-01
This study was carried out to evaluate the progression of visual function impairment in carriers of X-linked recessive retinitis pigmentosa. We also assessed the relationship between the retinal findings at presentation and the extent of deterioration. Observational, retrospective, case series. Twenty-seven carriers of X-linked recessive retinitis pigmentosa. Each carrier was clinically categorized into one of four grades (grades 0 through 3) depending on the presence or absence of a tapetal-like retinal reflex and the extent of peripheral pigmentary degeneration. A complete ophthalmologic examination was performed and data for visual acuity, visual field area, and electroretinographic measurements were collected on the most recent visit in both eyes. These were then compared with similar data obtained on their initial visits. A comparison of visual function was carried out between the initial visit and the most recent visit on each carrier. The visual acuity was measured with Snellen's acuity charts. The visual fields to targets V-4-e and II-4-e were planimeterized and used for the analysis. The electroretinographic (ERG) measures used were light-adapted single-flash b-wave amplitudes and 30-Hz red flicker for cone function, dark-adapted maximal b-wave amplitudes, and response to a low intensity blue-flash for rod function. None of the 11 carriers with a tapetal-like reflex only (grade 1) showed any significant change in visual acuity or fields as compared with 3 of 7 (43%) carriers with diffuse peripheral pigmentary findings (grade 3) who showed significant deterioration in visual acuity in at least one eye, and 6 of 7 (86%) who showed a significant decrease in visual field area with at least one target size in at least one eye. By comparison, only 1 of 10 carriers with a grade 1 fundus finding demonstrated a significant decrease in maximal dark-adapted ERG function as compared with 5 of 6 (83%) carriers with grade 3 in response to a single-flash stimulus and
-
From Process Understanding Via Soil Functions to Sustainable Soil Management - A Systemic Approach
Wollschlaeger, U.; Bartke, S.; Bartkowski, B.; Daedlow, K.; Helming, K.; Kogel-Knabner, I.; Lang, B.; Rabot, E.; Russell, D.; Stößel, B.; Weller, U.; Wiesmeier, M.; Rabot, E.; Vogel, H. J.
2017-12-01
Fertile soils are central resources for the production of biomass and the provision of food and energy. A growing world population and latest climate targets lead to an increasing demand for both, food and bio-energy, which requires preserving and improving the long-term productivity of soils as a bio-economic resource. At the same time, other soil functions and ecosystem services need to be maintained: filter for clean water, carbon sequestration, provision and recycling of nutrients, and habitat for biological activity. All these soil functions result from the interaction of a multitude of physical, chemical and biological processes that are not yet sufficiently understood. In addition, we lack understanding about the interplay between the socio-economic system and the soil system and how soil functions benefit human wellbeing. Hence, a solid and integrated assessment of soil quality requires the consideration of the ensemble of soil functions and its relation to soil management to finally be able to develop site-specific options for sustainable soil management. We present an integrated modeling approach that investigates the influence of soil management on the ensemble of soil functions. It is based on the mechanistic relationships between soil functional attributes, each explained by a network of interacting processes as derived from scientific evidence. As the evidence base required for feeding the model is for the most part stored in the existing scientific literature, another central component of our work is to set up a public "knowledge-portal" providing the infrastructure for a community effort towards a comprehensive knowledge base on soil processes as a basis for model developments. The connection to the socio-economic system is established using the Drivers-Pressures-Impacts-States-Responses (DPSIR) framework where our improved understanding about soil ecosystem processes is linked to ecosystem services and resource efficiency via the soil functions.
-
Directory of Open Access Journals (Sweden)
Raj Kumar Chopra
2016-09-01
Full Text Available Non functional requirements must be selected for implementation together with functional requirements to enhance the success of software projects. Three approaches exist for performing the prioritization of non functional requirements using the suitable prioritization technique. This paper performs experimentation on three different complexity versions of the industrial software project using cost-value prioritization technique employing three approaches. Experimentation is conducted to analyze the accuracy of individual approaches and the variation of accuracy with the complexity of the software project. The results indicate that selecting non functional requirements separately, but in accordance with functionality has higher accuracy amongst the other two approaches. Further, likewise other approaches, it witnesses the decrease in accuracy with increase in software complexity but the decrease is minimal.
-
Linking genes to microbial growth kinetics: an integrated biochemical systems engineering approach.
Koutinas, Michalis; Kiparissides, Alexandros; Silva-Rocha, Rafael; Lam, Ming-Chi; Martins Dos Santos, Vitor A P; de Lorenzo, Victor; Pistikopoulos, Efstratios N; Mantalaris, Athanasios
2011-07-01
The majority of models describing the kinetic properties of a microorganism for a given substrate are unstructured and empirical. They are formulated in this manner so that the complex mechanism of cell growth is simplified. Herein, a novel approach for modelling microbial growth kinetics is proposed, linking biomass growth and substrate consumption rates to the gene regulatory programmes that control these processes. A dynamic model of the TOL (pWW0) plasmid of Pseudomonas putida mt-2 has been developed, describing the molecular interactions that lead to the transcription of the upper and meta operons, known to produce the enzymes for the oxidative catabolism of m-xylene. The genetic circuit model was combined with a growth kinetic model decoupling biomass growth and substrate consumption rates, which are expressed as independent functions of the rate-limiting enzymes produced by the operons. Estimation of model parameters and validation of the model's predictive capability were successfully performed in batch cultures of mt-2 fed with different concentrations of m-xylene, as confirmed by relative mRNA concentration measurements of the promoters encoded in TOL. The growth formation and substrate utilisation patterns could not be accurately described by traditional Monod-type models for a wide range of conditions, demonstrating the critical importance of gene regulation for the development of advanced models closely predicting complex bioprocesses. In contrast, the proposed strategy, which utilises quantitative information pertaining to upstream molecular events that control the production of rate-limiting enzymes, predicts the catabolism of a substrate and biomass formation and could be of central importance for the design of optimal bioprocesses. Copyright © 2011 Elsevier Inc. All rights reserved.
-
Generalized Wigner functions in curved spaces: A new approach
International Nuclear Information System (INIS)
Kandrup, H.E.
1988-01-01
It is well known that, given a quantum field in Minkowski space, one can define Wigner functions f/sub W//sup N/(x 1 ,p 1 ,...,x/sub N/,p/sub N/) which (a) are convenient to analyze since, unlike the field itself, they are c-number quantities and (b) can be interpreted in a limited sense as ''quantum distribution functions.'' Recently, Winter and Calzetta, Habib and Hu have shown one way in which these flat-space Wigner functions can be generalized to a curved-space setting, deriving thereby approximate kinetic equations which make sense ''quasilocally'' for ''short-wavelength modes.'' This paper suggests a completely orthogonal approach for defining curved-space Wigner functions which generalizes instead an object such as the Fourier-transformed f/sub W/ 1 (k,p), which is effectively a two-point function viewed in terms of the ''natural'' creation and annihilation operators a/sup dagger/(p-(12k) and a(p+(12k). The approach suggested here lacks the precise phase-space interpretation implicit in the approach of Winter or Calzetta, Habib, and Hu, but it is useful in that (a) it is geared to handle any ''natural'' mode decomposition, so that (b) it can facilitate exact calculations at least in certain limits, such as for a source-free linear field in a static spacetime
-
Exploring candidate biological functions by Boolean Function Networks for Saccharomyces cerevisiae.
Directory of Open Access Journals (Sweden)
Maria Simak
Full Text Available The great amount of gene expression data has brought a big challenge for the discovery of Gene Regulatory Network (GRN. For network reconstruction and the investigation of regulatory relations, it is desirable to ensure directness of links between genes on a map, infer their directionality and explore candidate biological functions from high-throughput transcriptomic data. To address these problems, we introduce a Boolean Function Network (BFN model based on techniques of hidden Markov model (HMM, likelihood ratio test and Boolean logic functions. BFN consists of two consecutive tests to establish links between pairs of genes and check their directness. We evaluate the performance of BFN through the application to S. cerevisiae time course data. BFN produces regulatory relations which show consistency with succession of cell cycle phases. Furthermore, it also improves sensitivity and specificity when compared with alternative methods of genetic network reverse engineering. Moreover, we demonstrate that BFN can provide proper resolution for GO enrichment of gene sets. Finally, the Boolean functions discovered by BFN can provide useful insights for the identification of control mechanisms of regulatory processes, which is the special advantage of the proposed approach. In combination with low computational complexity, BFN can serve as an efficient screening tool to reconstruct genes relations on the whole genome level. In addition, the BFN approach is also feasible to a wide range of time course datasets.
-
Non-invasive brain-to-brain interface (BBI: establishing functional links between two brains.
Directory of Open Access Journals (Sweden)
Seung-Schik Yoo
Full Text Available Transcranial focused ultrasound (FUS is capable of modulating the neural activity of specific brain regions, with a potential role as a non-invasive computer-to-brain interface (CBI. In conjunction with the use of brain-to-computer interface (BCI techniques that translate brain function to generate computer commands, we investigated the feasibility of using the FUS-based CBI to non-invasively establish a functional link between the brains of different species (i.e. human and Sprague-Dawley rat, thus creating a brain-to-brain interface (BBI. The implementation was aimed to non-invasively translate the human volunteer's intention to stimulate a rat's brain motor area that is responsible for the tail movement. The volunteer initiated the intention by looking at a strobe light flicker on a computer display, and the degree of synchronization in the electroencephalographic steady-state-visual-evoked-potentials (SSVEP with respect to the strobe frequency was analyzed using a computer. Increased signal amplitude in the SSVEP, indicating the volunteer's intention, triggered the delivery of a burst-mode FUS (350 kHz ultrasound frequency, tone burst duration of 0.5 ms, pulse repetition frequency of 1 kHz, given for 300 msec duration to excite the motor area of an anesthetized rat transcranially. The successful excitation subsequently elicited the tail movement, which was detected by a motion sensor. The interface was achieved at 94.0±3.0% accuracy, with a time delay of 1.59±1.07 sec from the thought-initiation to the creation of the tail movement. Our results demonstrate the feasibility of a computer-mediated BBI that links central neural functions between two biological entities, which may confer unexplored opportunities in the study of neuroscience with potential implications for therapeutic applications.
-
How do SMA-linked mutations of SMN1 lead to structural/functional deficiency of the SMA protein?
Directory of Open Access Journals (Sweden)
Wei Li
Full Text Available Spinal muscular atrophy (SMA is an autosomal recessive neuromuscular disease with dysfunctional α-motor neurons in the anterior horn of the spinal cord. SMA is caused by loss (∼95% of SMA cases or mutation (∼5% of SMA cases of the survival motor neuron 1 gene SMN1. As the product of SMN1, SMN is a component of the SMN complex, and is also involved in the biosynthesis of the small nuclear ribonucleoproteins (snRNPs, which play critical roles in pre-mRNA splicing in the pathogenesis of SMA. To investigate how SMA-linked mutations of SMN1 lead to structural/functional deficiency of SMN, a set of computational analysis of SMN-related structures were conducted and are described in this article. Of extraordinary interest, the structural analysis highlights three SMN residues (Asp44, Glu134 and Gln136 with SMA-linked missense mutations, which cause disruptions of electrostatic interactions for Asp44, Glu134 and Gln136, and result in three functionally deficient SMA-linked SMN mutants, Asp44Val, Glu134Lys and Gln136Glu. From the computational analysis, it is also possible that SMN's Lys45 and Asp36 act as two electrostatic clips at the SMN-Gemin2 complex structure interface.
-
Allocating structure to function: the strong links between neuroplasticity and natural selection
Directory of Open Access Journals (Sweden)
Michael L Anderson
2014-01-01
Full Text Available A central question in brain evolution is how species-typical behaviors, and the neural function-structure mappings supporting them, can be acquired and inherited. Advocates of brain modularity, in its different incarnations across scientific subfields, argue that natural selection must target domain-dedicated, separately modifiable neural subsystems, resulting in genetically-specified functional modules. In such modular systems, specification of neuron number and functional connectivity are necessarily linked. Mounting evidence, however, from allometric, developmental, comparative, systems-physiological, neuroimaging and neurological studies suggests that brain elements are used and reused in multiple functional systems. This variable allocation can be seen in short-term neuromodulation, in neuroplasticity over the lifespan and in response to damage. We argue that the same processes are evident in brain evolution. Natural selection must preserve behavioral functions that may co-locate in variable amounts with other functions. In genetics, the uses and problems of pleiotropy, the re-use of genes in multiple networks have been much discussed, but this issue has been sidestepped in neural systems by the invocation of modules. Here we highlight the interaction between evolutionary and developmental mechanisms to produce distributed and overlapping functional architectures in the brain. These adaptive mechanisms must be robust to perturbations that might disrupt critical information processing and action selection, but must also recognize useful new sources of information arising from internal genetic or environmental variability, when those appear. These contrasting properties of robustness and evolvability have been discussed for the basic organization of body plan and fundamental cell physiology. Here we extend them to the evolution and development, evo-devo, of brain structure.
-
Directory of Open Access Journals (Sweden)
Adrien De Voeght
Full Text Available Microbial translocation is now viewed as a central event in the pathogenesis of chronic inflammation during HIV infection. Thymic function failure is another crucial factor involved in HIV disease progression. The goal of this study was to explore the hypothesis of potential links between microbial translocation and thymic function in HIV-1 patients living in Belgium. The extent of microbial translocation was assessed through the measurement of soluble CD14 (sCD14. T-cell receptor excision circles (sjTRECs and dβTRECs were used as a measure of thymic function. Data were collected from 75 HIV-infected patients. Simple and complex linear regressions were done to analyze the link between these two processes. We found a statistically relevant negative correlation between thymopoiesis (sjTREC and sCD14 level (p = 0.004. These results suggest a link between thymic function failure, microbial translocation and innate immune activation.
-
The potential-free approach to the construction of the NN-wave functions
International Nuclear Information System (INIS)
Troitsky, V.E.
1984-01-01
The traditional approaches to the nonrelativistic NN-interaction use local and nonlocal potentials of the kind defined by different dynamical speculations. The wave functions are obtained then from the Schroedinger equation with the chosen potential. Here the author obtains the wave functions (scattering wave function and bound state wave function) directly from the scattering phases in the frame of a dispersion approach without use of potential. (Auth.)
-
Directory of Open Access Journals (Sweden)
Watson-Haigh Nathan S
2010-06-01
Full Text Available Abstract Background Whole genome association studies using highly dense single nucleotide polymorphisms (SNPs are a set of methods to identify DNA markers associated with variation in a particular complex trait of interest. One of the main outcomes from these studies is a subset of statistically significant SNPs. Finding the potential biological functions of such SNPs can be an important step towards further use in human and agricultural populations (e.g., for identifying genes related to susceptibility to complex diseases or genes playing key roles in development or performance. The current challenge is that the information holding the clues to SNP functions is distributed across many different databases. Efficient bioinformatics tools are therefore needed to seamlessly integrate up-to-date functional information on SNPs. Many web services have arisen to meet the challenge but most work only within the framework of human medical research. Although we acknowledge the importance of human research, we identify there is a need for SNP annotation tools for other organisms. Description We introduce an R package called FunctSNP, which is the user interface to custom built species-specific databases. The local relational databases contain SNP data together with functional annotations extracted from online resources. FunctSNP provides a unified bioinformatics resource to link SNPs with functional knowledge (e.g., genes, pathways, ontologies. We also introduce dbAutoMaker, a suite of Perl scripts, which can be scheduled to run periodically to automatically create/update the customised SNP databases. We illustrate the use of FunctSNP with a livestock example, but the approach and software tools presented here can be applied also to human and other organisms. Conclusions Finding the potential functional significance of SNPs is important when further using the outcomes from whole genome association studies. FunctSNP is unique in that it is the only R
-
Speaker Linking and Applications using Non-Parametric Hashing Methods
2016-09-08
nonparametric estimate of a multivariate density function,” The Annals of Math- ematical Statistics , vol. 36, no. 3, pp. 1049–1051, 1965. [9] E. A. Patrick...Speaker Linking and Applications using Non-Parametric Hashing Methods† Douglas Sturim and William M. Campbell MIT Lincoln Laboratory, Lexington, MA...with many approaches [1, 2]. For this paper, we focus on using i-vectors [2], but the methods apply to any embedding. For the task of speaker QBE and
-
Radiological emergency response - a functional approach
International Nuclear Information System (INIS)
Chowdhury, Prosanta
1997-01-01
The radiological emergency response program in the State of Louisiana is discussed. The improved approach intends to maximize the efficiency for both nuclear power plant and radiological emergency response as a whole. Several broad-based components are identified: cluster of 'nodes' are generated for each component; these 'nodes' may be divided into 'sub-nodes' which will contain some 'attributes'; 'relational bonds' among the 'attributes' will exist. When executed, the process begins and continues with the 'nodes' assuming a functional and dynamic role based on the nature and characteristics of the 'attributes'. The typical response based on stand-alone elements is eliminated; overlapping of functions is avoided, and is produced a well-structure and efficient organization
-
The Feynman-Vernon Influence Functional Approach in QED
International Nuclear Information System (INIS)
Biryukov, Alexander; Shleenkov, Mark
2016-01-01
In the path integral approach we describe evolution of interacting electromagnetic and fermionic fields by the use of density matrix formalism. The equation for density matrix and transitions probability for fermionic field is obtained as average of electromagnetic field influence functional. We obtain a formula for electromagnetic field influence functional calculating for its various initial and final state. We derive electromagnetic field influence functional when its initial and final states are vacuum. We present Lagrangian for relativistic fermionic field under influence of electromagnetic field vacuum
-
Pemodelan Matematika Premi Tunggal Bersih Asuransi Unit Link Syariah
Directory of Open Access Journals (Sweden)
Nanang Supriadi
2017-12-01
Full Text Available The exact risk factor can be managed by transferring the risk to the other party (in this case the insurance company. In this paper will be discussed more life insurance, as the development now there are types of insurance combined with investment, which is popular with the term Unit Link insurance. Unit link Syariah began to be launched as one of the fulfilment of the high needs of the community, the privilege of the product Unit of Islamic links is actually located in the elements of the laws in accordance with Islamic Syariah. The issues that will be discussed are how to get a single premium model of life insurance unit link Syariah with life insurance and investment fund allocation invested in investment product with a big interest rate of risk (financial approach and investment product with the value of return maximum (actuarial approach. The resulting model is then implemented in case of examples by comparing the two approaches to see the shortcomings and advantages of Unit link lifetime life insurance when compared to life insurance. The result obtained from this research is the benefit obtained from Unit-linked sharia insurance on average will be greater if compared with life insurance for life, maximum benefit will be obtained Insurance Unit Link of sharia using actuarial approach compared to financial, but benefit with a relative financial approach more stable than actuarial approaches that tend to fluctuate.
-
The quantification or estimation of the economic and non-economic values of ecosystem services can be done from a number of distinct approaches. For example, practitioners may use ecosystem services production function models (ESPFMs) for a particular location, or alternatively, ...
-
Vidal, Franck; Burle, Boris; Spieser, Laure; Carbonnell, Laurence; Meckler, Cédric; Casini, Laurence; Hasbroucq, Thierry
2015-09-01
Electroencephalography (EEG) is a very popular technique for investigating brain functions and/or mental processes. To this aim, EEG activities must be interpreted in terms of brain and/or mental processes. EEG signals being a direct manifestation of neuronal activity it is often assumed that such interpretations are quite obvious or, at least, straightforward. However, they often rely on (explicit or even implicit) assumptions regarding the structures supposed to generate the EEG activities of interest. For these assumptions to be used appropriately, reliable links between EEG activities and the underlying brain structures must be established. Because of volume conduction effects and the mixture of activities they induce, these links are difficult to establish with scalp potential recordings. We present different examples showing how the Laplacian transformation, acting as an efficient source separation method, allowed to establish more reliable links between EEG activities and brain generators and, ultimately, with mental operations. The nature of those links depends on the depth of inferences that can vary from weak to strong. Along this continuum, we show that 1) while the effects of experimental manipulation can appear widely distributed with scalp potentials, Laplacian transformation allows to reveal several generators contributing (in different manners) to these modulations, 2) amplitude variations within the same set of generators can generate spurious differences in scalp potential topographies, often interpreted as reflecting different source configurations. In such a case, Laplacian transformation provides much more similar topographies, evidencing the same generator(s) set, and 3) using the LRP as an index of response activation most often produces ambiguous results, Laplacian-transformed response-locked ERPs obtained over motor areas allow resolving these ambiguities. Copyright © 2015 Elsevier B.V. All rights reserved.
-
Pediatrician's knowledge on the approach of functional constipation
Vieira, Mario C.; Negrelle, Isadora Carolina Krueger; Webber, Karla Ulaf; Gosdal, Marjorie; Truppel, Sabine Krüger; Kusma, Solena Ziemer
2016-01-01
Abstract Objective: To evaluate the pediatrician's knowledge regarding the diagnostic and therapeutic approach of childhood functional constipation. Methods: A descriptive cross-sectional study was performed with the application of a self-administered questionnaire concerning a hypothetical clinical case of childhood functional constipation with fecal incontinence to physicians (n=297) randomly interviewed at the 36th Brazilian Congress of Pediatrics in 2013. Results: The majority of the p...
-
A Comprehensive Approach for Pectin Chemical and Functional Characterization
DEFF Research Database (Denmark)
de Sousa, António Felipe Gomes Teixeira
In this work, a comprehensive approach for the chemical and functional analysis of pectin was used in order to relate the different extraction conditions used to the polymer structure and the final functional (mainly gelling) properties. A wide range of methods were utilized including chemical an...
-
Exponentiation for products of Wilson lines within the generating function approach
International Nuclear Information System (INIS)
Vladimirov, A.A.
2015-01-01
We present the generating function approach to the perturbative exponentiation of correlators of a product of Wilson lines and loops. The exponentiated expression is presented in closed form as an algebraic function of correlators of known operators, which can be seen as a generating function for web diagrams. The expression is naturally split onto two parts: the exponentiation kernel, which accumulates all non-trivial information about web diagrams, and the defect of exponentiation, which reconstructs the matrix exponent and is a function of the exponentiation kernel. The detailed comparison of the presented approach with existing approaches to exponentiation is presented as well. We also give examples of calculations within the generating function exponentiation, namely, we consider different configurations of light-like Wilson lines in the multi-gluon-exchange-webs (MGEW) approximation. Within this approximation the corresponding correlators can be calculated exactly at any order of perturbative expansion by only algebraic manipulations. The MGEW approximation shows violation of the dipole formula for infrared singularities at three-loop order.
-
Removal of anionic azo dyes from aqueous solution by functional ionic liquid cross-linked polymer
International Nuclear Information System (INIS)
Gao, Hejun; Kan, Taotao; Zhao, Siyuan; Qian, Yixia; Cheng, Xiyuan; Wu, Wenli; Wang, Xiaodong; Zheng, Liqiang
2013-01-01
Highlights: • Equilibrium, kinetic and thermodynamic of adsorption of dyes onto PDVB-IL was investigated. • PDVB-IL has a high adsorption capacity to treat dyes solution. • Higher adsorption capacity is due to the functional groups of PDVB-IL. • Molecular structure of dyes influences the adsorption capacity. -- Abstract: A novel functional ionic liquid based cross-linked polymer (PDVB-IL) was synthesized from 1-aminoethyl-3-vinylimidazolium chloride and divinylbenzene for use as an adsorbent. The physicochemical properties of PDVB-IL were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis. The adsorptive capacity was investigated using anionic azo dyes of orange II, sunset yellow FCF, and amaranth as adsorbates. The maximum adsorption capacity could reach 925.09, 734.62, and 547.17 mg/g for orange II, sunset yellow FCF and amaranth at 25 °C, respectively, which are much better than most of the other adsorbents reported earlier. The effect of pH value was investigated in the range of 1–8. The result shows that a low pH value is found to favor the adsorption of those anionic azo dyes. The adsorption kinetics and isotherms are well fitted by a pseudo second-order model and Langmuir model, respectively. The adsorption process is found to be dominated by physisorption. The introduction of functional ionic liquid moieties into cross-linked poly(divinylbenzene) polymer constitutes a new and efficient kind of adsorbent
-
Link-Based Similarity Measures Using Reachability Vectors
Directory of Open Access Journals (Sweden)
Seok-Ho Yoon
2014-01-01
Full Text Available We present a novel approach for computing link-based similarities among objects accurately by utilizing the link information pertaining to the objects involved. We discuss the problems with previous link-based similarity measures and propose a novel approach for computing link based similarities that does not suffer from these problems. In the proposed approach each target object is represented by a vector. Each element of the vector corresponds to all the objects in the given data, and the value of each element denotes the weight for the corresponding object. As for this weight value, we propose to utilize the probability of reaching from the target object to the specific object, computed using the “Random Walk with Restart” strategy. Then, we define the similarity between two objects as the cosine similarity of the two vectors. In this paper, we provide examples to show that our approach does not suffer from the aforementioned problems. We also evaluate the performance of the proposed methods in comparison with existing link-based measures, qualitatively and quantitatively, with respect to two kinds of data sets, scientific papers and Web documents. Our experimental results indicate that the proposed methods significantly outperform the existing measures.
-
Non-perturbative construction of the Luttinger-Ward functional
Directory of Open Access Journals (Sweden)
M.Potthoff
2006-01-01
Full Text Available For a system of correlated electrons, the Luttinger-Ward functional provides a link between static thermodynamic quantities on the one hand and single-particle excitations on the other. The functional is useful in deriving several general properties of the system as well as in formulating the thermodynamically consistent approximations. Its original construction, however, is perturbative as it is based on the weak-coupling skeleton-diagram expansion. Here, it is shown that the Luttinger-Ward functional can be derived within a general functional-integral approach. This alternative and non-perturbative approach stresses the fact that the Luttinger-Ward functional is universal for a large class of models.
-
Directory of Open Access Journals (Sweden)
Robert D. Davic
2003-07-01
Full Text Available The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups at lower trophic levels that are structured by competition for a limited resource. The a priori prediction of keystone species has applied value for the conservation of natural areas.
-
[Sex-linked juvenile retinoschisis].
François, P; Turut, P; Soltysik, C; Hache, J C
1976-02-01
About 13 observations of sexe linked juvenile retinoschisis, the authors describe the ophthalmoscopic, fluorographic and functional aspects of the disease whose caracteristics are:--its sexe linked recessive heredity; --its clinical characterestics associating: a microcystic macular degeneration, peripheral retinal lesions, vitreous body alterations, --an electroretinogram of the negative type.
-
Analysis of Anatomic and Functional Measures in X-Linked Retinoschisis
Cukras, Catherine A.; Huryn, Laryssa A.; Jeffrey, Brett P.; Turriff, Amy; Sieving, Paul A.
2018-01-01
Purpose To examine the symmetry of structural and functional parameters between eyes in patients with X-linked retinoschisis (XLRS), as well as changes in visual acuity and electrophysiology over time. Methods This is a single-center observational study of 120 males with XLRS who were evaluated at the National Eye Institute. Examinations included best-corrected visual acuity for all participants, as well as ERG recording and optical coherence tomography (OCT) on a subset of participants. Statistical analyses were performed using nonparametric Spearman correlations and linear regression. Results Our analyses demonstrated a statistically significant correlation of structural and functional measures between the two eyes of XLRS patients for all parameters. OCT central macular thickness (n = 78; Spearman r = 0.83, P < 0.0001) and ERG b/a ratio (n = 78; Spearman r = 0.82, P < 0.0001) were the most strongly correlated between a participant's eyes, whereas visual acuity was less strongly correlated (n = 120; Spearman r = 0.47, P < 0.0001). Stability of visual acuity was observed with an average change of less than one letter (n = 74; OD −0.66 and OS −0.70 letters) in a mean follow-up time of 6.8 years. There was no statistically significant change in the ERG b/a ratio within eyes over time. Conclusions Although a broad spectrum of clinical phenotypes is observed across individuals with XLRS, our study demonstrates a significant correlation of structural and functional findings between the two eyes and stability of measures of acuity and ERG parameters over time. These results highlight the utility of the fellow eye as a useful reference for monocular interventional trials.
-
Radiological emergency response - a functional approach
Energy Technology Data Exchange (ETDEWEB)
Chowdhury, Prosanta [Louisiana Radiation Protection Div., Baton Rouge, LA (United States)
1997-12-31
The radiological emergency response program in the State of Louisiana is discussed. The improved approach intends to maximize the efficiency for both nuclear power plant and radiological emergency response as a whole. Several broad-based components are identified: cluster of `nodes` are generated for each component; these `nodes` may be divided into `sub-nodes` which will contain some `attributes`; `relational bonds` among the `attributes` will exist. When executed, the process begins and continues with the `nodes` assuming a functional and dynamic role based on the nature and characteristics of the `attributes`. The typical response based on stand-alone elements is eliminated; overlapping of functions is avoided, and is produced a well-structure and efficient organization 1 ref., 6 figs.; e-mail: prosanta at deq.state.la.us
-
Selling and Building Linked Data: Drive Value and Gain Momentum
Harris, Kristen
Data inside enterprises is exploding. Routinely key decision makers state, "one of the most valuable assets of our organization is actionable information." Paradoxically, it is often challenging to gather the necessary metrics to build a business case to justify a Linked Data initiative for improved data quality in the face of the well-documented shortcomings of traditional enterprise approaches to data management. Internet standards have matured considerably in the last decade. The number of linked data sets is growing daily and already exceeds well in excess of ten thousand data sets, over 400 of which are published via the US Government at gov as of April 2010. Many of these linked data sets are high quality. Best practices for linking data within the enterprise are increasingly being published in articles, blogs and technical books. One of the pioneering linked enterprise data projects was undertaken by a Fortune 500 company in the early 2000 timeframe. The lessons learned about how to navigate the management and organizational dynamics are relevant today. This chapter outlines the successful strategies for a linked enterprise data initiative, including a consistent metadata management strategy across lines of business, definition and documentation of data ownership and the value of cross-functional teams in the definition, development and deployment of the project.
-
a Task-Driven Disaster Data Link Approach
Qiu, L. Y.; Zhu, Q.; Gu, J. Y.; Du, Z. Q.
2015-08-01
With the rapid development of sensor networks and Earth observation technology, a large quantity of disaster-related data is available, such as remotely sensed data, historic data, cases data, simulation data, disaster products and so on. However, the efficiency of current data management and service systems has become increasingly serious due to the task variety and heterogeneous data. For emergency task-oriented applications, data searching mainly relies on artificial experience based on simple metadata index, whose high time-consuming and low accuracy cannot satisfy the requirements of disaster products on velocity and veracity. In this paper, a task-oriented linking method is proposed for efficient disaster data management and intelligent service, with the objectives of 1) putting forward ontologies of disaster task and data to unify the different semantics of multi-source information, 2) identifying the semantic mapping from emergency tasks to multiple sources on the basis of uniform description in 1), 3) linking task-related data automatically and calculating the degree of correlation between each data and a target task. The method breaks through traditional static management of disaster data and establishes a base for intelligent retrieval and active push of disaster information. The case study presented in this paper illustrates the use of the method with a flood emergency relief task.
-
A review of function modeling: Approaches and applications
Erden, M.S.; Komoto, H.; Van Beek, T.J.; D'Amelio, V.; Echavarria, E.; Tomiyama, T.
2008-01-01
This work is aimed at establishing a common frame and understanding of function modeling (FM) for our ongoing research activities. A comparative review of the literature is performed to grasp the various FM approaches with their commonalities and differences. The relations of FM with the research fields of artificial intelligence, design theory, and maintenance are discussed. In this discussion the goals are to highlight the features of various classical approaches in relation to FM, to delin...
-
Linking disease associations with regulatory information in the human genome
Schaub, M. A.; Boyle, A. P.; Kundaje, A.; Batzoglou, S.; Snyder, M.
2012-01-01
Genome-wide association studies have been successful in identifying single nucleotide polymorphisms (SNPs) associated with a large number of phenotypes. However, an associated SNP is likely part of a larger region of linkage disequilibrium. This makes it difficult to precisely identify the SNPs that have a biological link with the phenotype. We have systematically investigated the association of multiple types of ENCODE data with disease-associated SNPs and show that there is significant enrichment for functional SNPs among the currently identified associations. This enrichment is strongest when integrating multiple sources of functional information and when highest confidence disease-associated SNPs are used. We propose an approach that integrates multiple types of functional data generated by the ENCODE Consortium to help identify "functional SNPs" that may be associated with the disease phenotype. Our approach generates putative functional annotations for up to 80% of all previously reported associations. We show that for most associations, the functional SNP most strongly supported by experimental evidence is a SNP in linkage disequilibrium with the reported association rather than the reported SNP itself. Our results show that the experimental data sets generated by the ENCODE Consortium can be successfully used to suggest functional hypotheses for variants associated with diseases and other phenotypes.
-
Linking disease associations with regulatory information in the human genome
Schaub, M. A.
2012-09-01
Genome-wide association studies have been successful in identifying single nucleotide polymorphisms (SNPs) associated with a large number of phenotypes. However, an associated SNP is likely part of a larger region of linkage disequilibrium. This makes it difficult to precisely identify the SNPs that have a biological link with the phenotype. We have systematically investigated the association of multiple types of ENCODE data with disease-associated SNPs and show that there is significant enrichment for functional SNPs among the currently identified associations. This enrichment is strongest when integrating multiple sources of functional information and when highest confidence disease-associated SNPs are used. We propose an approach that integrates multiple types of functional data generated by the ENCODE Consortium to help identify "functional SNPs" that may be associated with the disease phenotype. Our approach generates putative functional annotations for up to 80% of all previously reported associations. We show that for most associations, the functional SNP most strongly supported by experimental evidence is a SNP in linkage disequilibrium with the reported association rather than the reported SNP itself. Our results show that the experimental data sets generated by the ENCODE Consortium can be successfully used to suggest functional hypotheses for variants associated with diseases and other phenotypes.
-
Directory of Open Access Journals (Sweden)
James R. Hall
2011-01-01
Full Text Available Objectives. To investigate the link between neurocognitive measures and various aspects of daily living (ADL and IADL in women and men with mild Alzheimer's disease (AD. Methods. Participants were 202 AD patients (91 male, 111 female with CDR global scores of ≤1. ADLs and IADLs ratings were obtained from caregivers. Cognitive domains were assessed with neuropsychological testing. Results. Memory and executive functioning were related to IADL scores. Executive functioning was linked to total ADL. Comparisons stratified on gender found attention predicted total ADL score in both men and women. Attention predicted bathing and eating ability in women only. Language predicted IADL functions in men (food preparation and women (driving. Conclusions. Associations between ADLs/IADLs and memory, learning, executive functioning, and language suggest that even in patients with mild AD, basic ADLs require complex cognitive processes. Gender differences in the domains of learning and memory area were found.
-
A functional approach for managing ITER operations
International Nuclear Information System (INIS)
Houtte, Didier van; Sagot, François; Okayama, Katsumi; Blackler, Kenneth
2012-01-01
Highlights: ► A function-oriented approach for defining and organizing all the functions required to perform the mission has been developed. ► A Functional Breakdown Structure providing a complete hierarchy of functions on multiple levels is presented. ► The FBS is used for giving a good visibility of ITER project needs and requirements. ► Reliability (R) and Inherent Availability (A I ) of basic functions are calculated from data on the structures, systems and components (failure rate and time to repair) for obtaining the Availability objectives of the ITER project. - Abstract: ITER is currently the most ambitious project on nuclear fusion research. Its objective is to demonstrate the feasibility of fusion as an energy source for the future. The complexity of the systems required to meet this challenge present many opportunities for omissions or incorrect assumptions. System engineering allows the engineer to deal with such a complexity by developing a Functional Breakdown Structure (FBS). Unlike a Plant Breakdown Structure (PBS), the FBS is a function-oriented tree, not a product-oriented tree. It details operations or activities that have to be performed as needed functions of the architecture, allowing identification of any missing elements, defining the personnel skills required to operate the architecture and managing the machine availability.
-
Liu, Min; Zhang, Zhongqi; Zang, Tianzhu; Spahr, Chris; Cheetham, Janet; Ren, Da; Zhou, Zhaohui Sunny
2013-06-18
Characterization of protein cross-linking, particularly without prior knowledge of the chemical nature and site of cross-linking, poses a significant challenge, because of their intrinsic structural complexity and the lack of a comprehensive analytical approach. Toward this end, we have developed a generally applicable workflow-XChem-Finder-that involves four stages: (1) detection of cross-linked peptides via (18)O-labeling at C-termini; (2) determination of the putative partial sequences of each cross-linked peptide pair using a fragment ion mass database search against known protein sequences coupled with a de novo sequence tag search; (3) extension to full sequences based on protease specificity, the unique combination of mass, and other constraints; and (4) deduction of cross-linking chemistry and site. The mass difference between the sum of two putative full-length peptides and the cross-linked peptide provides the formulas (elemental composition analysis) for the functional groups involved in each cross-linking. Combined with sequence restraint from MS/MS data, plausible cross-linking chemistry and site were inferred, and ultimately confirmed, by matching with all data. Applying our approach to a stressed IgG2 antibody, 10 cross-linked peptides were discovered and found to be connected via thioethers originating from disulfides at locations that had not been previously recognized. Furthermore, once the cross-link chemistry was revealed, a targeted cross-link search yielded 4 additional cross-linked peptides that all contain the C-terminus of the light chain.
-
Ecological-network models link diversity, structure and function in the plankton food-web
D'Alelio, Domenico; Libralato, Simone; Wyatt, Timothy; Ribera D'Alcalà, Maurizio
2016-02-01
A planktonic food-web model including sixty-three functional nodes (representing auto- mixo- and heterotrophs) was developed to integrate most trophic diversity present in the plankton. The model was implemented in two variants - which we named ‘green’ and ‘blue’ - characterized by opposite amounts of phytoplankton biomass and representing, respectively, bloom and non-bloom states of the system. Taxonomically disaggregated food-webs described herein allowed to shed light on how components of the plankton community changed their trophic behavior in the two different conditions, and modified the overall functioning of the plankton food web. The green and blue food-webs showed distinct organizations in terms of trophic roles of the nodes and carbon fluxes between them. Such re-organization stemmed from switches in selective grazing by both metazoan and protozoan consumers. Switches in food-web structure resulted in relatively small differences in the efficiency of material transfer towards higher trophic levels. For instance, from green to blue states, a seven-fold decrease in phytoplankton biomass translated into only a two-fold decrease in potential planktivorous fish biomass. By linking diversity, structure and function in the plankton food-web, we discuss the role of internal mechanisms, relying on species-specific functionalities, in driving the ‘adaptive’ responses of plankton communities to perturbations.
-
Atkinson, Greg; Batterham, Alan M; Thijssen, Dick H J; Green, Daniel J
2013-02-01
Flow-mediated dilation (FMD) is a noninvasive indicator of endothelial function and is routinely expressed as the percentage change in arterial diameter (FMD%) from a resting baseline (Dbase) to a postischemic peak (Dpeak). This expression is equivalent to the ratio of Dpeak/Dbase and is, therefore, dependent on important statistical assumptions, which have never been analysed in the context of FMD%. We aimed to investigate these assumptions, via a comparison of FMD between samples of children and adults, as well as to explore other approaches to scaling diameter change for Dbase. We found that FMD% did not scale accurately for interindividual differences in Dbase but, as expected, overestimated endothelial function for low Dbase and vice versa. We argue that this imprecise scaling of FMD% is predictable, not explained by physiology and is probably common. This problem is resolved by applying scaling principles, whereby the difference in diameter is the outcome and Dbase is a covariate in a logarithmic-linked generalized linear model. A specific allometric expression of FMD can be derived and we found this to be Dpeak/Dbase rather than a simple ratio in our particular dataset. We found that sample differences in endothelial function were inaccurate with FMD% versus our new allometric approach, and that FMD% misclassified participants into 'high' and 'low'cohorts, which has implications for prognostic-type studies. We conclude that the general use of FMD% could have led to biased comparisons of different conditions and/or populations in past studies. Our new approach to scaling FMD is flexible for different datasets and is not based on the current assumption that a percentage change is appropriate in all circumstances.
-
A functional approach to emotion in autonomous systems.
Sanz, Ricardo; Hernández, Carlos; Gómez, Jaime; Hernando, Adolfo
2010-01-01
The construction of fully effective systems seems to pass through the proper exploitation of goal-centric self-evaluative capabilities that let the system teleologically self-manage. Emotions seem to provide this kind of functionality to biological systems and hence the interest in emotion for function sustainment in artificial systems performing in changing and uncertain environments; far beyond the media hullabaloo of displaying human-like emotion-laden faces in robots. This chapter provides a brief analysis of the scientific theories of emotion and presents an engineering approach for developing technology for robust autonomy by implementing functionality inspired in that of biological emotions.
-
Bock, Allison M.; Gallaway, Kristin C.; Hund, Alycia M.
2015-01-01
The purpose of this study was to specify the development of and links between executive functioning and theory of mind during middle childhood. One hundred four 7- to 12-year-old children completed a battery of age-appropriate tasks measuring working memory, inhibition, flexibility, theory of mind, and vocabulary. As expected, spatial working…
-
Comprehensive functional analysis of N-linked glycans on Ebola virus GP1.
Lennemann, Nicholas J; Rhein, Bethany A; Ndungo, Esther; Chandran, Kartik; Qiu, Xiangguo; Maury, Wendy
2014-01-28
Ebola virus (EBOV) entry requires the virion surface-associated glycoprotein (GP) that is composed of a trimer of heterodimers (GP1/GP2). The GP1 subunit contains two heavily glycosylated domains, the glycan cap and the mucin-like domain (MLD). The glycan cap contains only N-linked glycans, whereas the MLD contains both N- and O-linked glycans. Site-directed mutagenesis was performed on EBOV GP1 to systematically disrupt N-linked glycan sites to gain an understanding of their role in GP structure and function. All 15 N-glycosylation sites of EBOV GP1 could be removed without compromising the expression of GP. The loss of these 15 glycosylation sites significantly enhanced pseudovirion transduction in Vero cells, which correlated with an increase in protease sensitivity. Interestingly, exposing the receptor-binding domain (RBD) by removing the glycan shield did not allow interaction with the endosomal receptor, NPC1, indicating that the glycan cap/MLD domains mask RBD residues required for binding. The effects of the loss of GP1 N-linked glycans on Ca(2+)-dependent (C-type) lectin (CLEC)-dependent transduction were complex, and the effect was unique for each of the CLECs tested. Surprisingly, EBOV entry into murine peritoneal macrophages was independent of GP1 N-glycans, suggesting that CLEC-GP1 N-glycan interactions are not required for entry into this important primary cell. Finally, the removal of all GP1 N-glycans outside the MLD enhanced antiserum and antibody sensitivity. In total, our results provide evidence that the conserved N-linked glycans on the EBOV GP1 core protect GP from antibody neutralization despite the negative impact the glycans have on viral entry efficiency. Filovirus outbreaks occur sporadically throughout central Africa, causing high fatality rates among the general public and health care workers. These unpredictable hemorrhagic fever outbreaks are caused by multiple species of Ebola viruses, as well as Marburg virus. While filovirus
-
Leadbetter, Adam; Arko, Robert; Chandler, Cynthia; Shepherd, Adam
2014-05-01
Data repositories. The benefits of this approach include: increased interoperability between the metadata created by projects; improved data discovery as users of SeaDataNet, R2R and BCO-DMO terms can find data using labels with which they are familiar both standard tools and newly developed custom tools may be used to explore the data; and using standards means the custom tools are easier to develop Linked Data is a concept which has been in existence for nearly a decade, and has a simple set of formal best practices associated with it. Linked Data is increasingly being seen as a driver of the next generation of "community science" activities. While many data providers in the oceanographic domain may be unaware of Linked Data, they may also be providing it at one of its lower levels. Here we have shown that it is possible to deliver the highest standard of Linked Oceanographic Data, and some of the benefits of the approach.
-
Magnetic Resonance and Brain Function. Approaches from Physics
International Nuclear Information System (INIS)
Maraviglia, B.
1999-01-01
In the last decade of this millennium, while, on the one hand, the international scientific community has focused with increasing endeavour on the research about the great unknown of the mechanism and the pathologies of the human brain, on the other hand, the NMR community has achieved some important results, which should widely affect, in the future, the possibility of understanding the function and disfunction of the human brain. In the early 1980's, the beginning of the application of Magnetic Resonance Imaging (MRI) to the morphological study of the brain in vivo, has played an extraordinary role, which, since then, placed MRI in a leading position among the methodologies used for investigation and diagnostics of the Central Nervous System. In the 1990s, the objective of finding new means, based on MRI, capable of giving functional and metabolic information, with the highest possible space resolution, drove the scientists towards different approaches. Among these, the first one to generate a breakthrough in the localization of specific cerebral functions was the Blood Oxygen Level Development (BOLD) MRI. A very wide range of applications followed the discovery of BOLD imaging. Still, this method gives an indirect information of the localization of functions, via the variation of oxygen release and deoxyhemoglobin formation. Of course, a high-resolution spatial distribution of the metabolites, crucial to brain function, would give a deeper insight into the occurring processes. This finality is aimed at by the Double Magnetic Resonance methods, which are developing new procedures able to detect some metabolites with increasing sensitivity and resolution. A third new promising approach to functional MRI should derive from the use of hyperpolarized, opens a series of potential applications to the study of brain function
-
Energy Technology Data Exchange (ETDEWEB)
Helton, Jon C. [Arizona State Univ., Tempe, AZ (United States); Brooks, Dusty Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sallaberry, Cedric Jean-Marie. [Engineering Mechanics Corp. of Columbus, OH (United States)
2018-02-01
Representations are developed and illustrated for the distribution of link property values at the time of link failure in the presence of aleatory uncertainty in link properties. The following topics are considered: (i) defining properties for weak links and strong links, (ii) cumulative distribution functions (CDFs) for link failure time, (iii) integral-based derivation of CDFs for link property at time of link failure, (iv) sampling-based approximation of CDFs for link property at time of link failure, (v) verification of integral-based and sampling-based determinations of CDFs for link property at time of link failure, (vi) distributions of link properties conditional on time of link failure, and (vii) equivalence of two different integral-based derivations of CDFs for link property at time of link failure.
-
A minimalist functional group (MFG) approach for surrogate fuel formulation
Abdul Jameel, Abdul Gani
2018-03-20
Surrogate fuel formulation has drawn significant interest due to its relevance towards understanding combustion properties of complex fuel mixtures. In this work, we present a novel approach for surrogate fuel formulation by matching target fuel functional groups, while minimizing the number of surrogate species. Five key functional groups; paraffinic CH, paraffinic CH, paraffinic CH, naphthenic CH–CH and aromatic C–CH groups in addition to structural information provided by the Branching Index (BI) were chosen as matching targets. Surrogates were developed for six FACE (Fuels for Advanced Combustion Engines) gasoline target fuels, namely FACE A, C, F, G, I and J. The five functional groups present in the fuels were qualitatively and quantitatively identified using high resolution H Nuclear Magnetic Resonance (NMR) spectroscopy. A further constraint was imposed in limiting the number of surrogate components to a maximum of two. This simplifies the process of surrogate formulation, facilitates surrogate testing, and significantly reduces the size and time involved in developing chemical kinetic models by reducing the number of thermochemical and kinetic parameters requiring estimation. Fewer species also reduces the computational expenses involved in simulating combustion in practical devices. The proposed surrogate formulation methodology is denoted as the Minimalist Functional Group (MFG) approach. The MFG surrogates were experimentally tested against their target fuels using Ignition Delay Times (IDT) measured in an Ignition Quality Tester (IQT), as specified by the standard ASTM D6890 methodology, and in a Rapid Compression Machine (RCM). Threshold Sooting Index (TSI) and Smoke Point (SP) measurements were also performed to determine the sooting propensities of the surrogates and target fuels. The results showed that MFG surrogates were able to reproduce the aforementioned combustion properties of the target FACE gasolines across a wide range of conditions
-
A minimalist functional group (MFG) approach for surrogate fuel formulation
Abdul Jameel, Abdul Gani; Naser, Nimal; Issayev, Gani; Touitou, Jamal; Ghosh, Manik Kumer; Emwas, Abdul-Hamid M.; Farooq, Aamir; Dooley, Stephen; Sarathy, Mani
2018-01-01
Surrogate fuel formulation has drawn significant interest due to its relevance towards understanding combustion properties of complex fuel mixtures. In this work, we present a novel approach for surrogate fuel formulation by matching target fuel functional groups, while minimizing the number of surrogate species. Five key functional groups; paraffinic CH, paraffinic CH, paraffinic CH, naphthenic CH–CH and aromatic C–CH groups in addition to structural information provided by the Branching Index (BI) were chosen as matching targets. Surrogates were developed for six FACE (Fuels for Advanced Combustion Engines) gasoline target fuels, namely FACE A, C, F, G, I and J. The five functional groups present in the fuels were qualitatively and quantitatively identified using high resolution H Nuclear Magnetic Resonance (NMR) spectroscopy. A further constraint was imposed in limiting the number of surrogate components to a maximum of two. This simplifies the process of surrogate formulation, facilitates surrogate testing, and significantly reduces the size and time involved in developing chemical kinetic models by reducing the number of thermochemical and kinetic parameters requiring estimation. Fewer species also reduces the computational expenses involved in simulating combustion in practical devices. The proposed surrogate formulation methodology is denoted as the Minimalist Functional Group (MFG) approach. The MFG surrogates were experimentally tested against their target fuels using Ignition Delay Times (IDT) measured in an Ignition Quality Tester (IQT), as specified by the standard ASTM D6890 methodology, and in a Rapid Compression Machine (RCM). Threshold Sooting Index (TSI) and Smoke Point (SP) measurements were also performed to determine the sooting propensities of the surrogates and target fuels. The results showed that MFG surrogates were able to reproduce the aforementioned combustion properties of the target FACE gasolines across a wide range of conditions
-
Geometry optimization of molecules within an LCGTO local-density functional approach
International Nuclear Information System (INIS)
Mintmire, J.W.
1990-01-01
We describe our implementation of geometry optimization techniques within the linear combination of Gaussian-type orbitals (LCGTO) approach to local-density functional theory. The algorithm for geometry optimization is based on the evaluation of the gradient of the total energy with respect to internal coordinates within the local-density functional scheme. We present optimization results for a range of small molecules which serve as test cases for our approach
-
How do companies envisage the future? Functional foresight approaches
Directory of Open Access Journals (Sweden)
Kononiuk Anna
2017-12-01
Full Text Available The main aim of the paper is to present the synthesis of the results of methodological analysis conducted on examples of foresight projects executed in chosen companies representing four companies type: small and medium-sized enterprise (SME, nonprofit- organization, international corporations and consulting companies as well as to posit functional approach for the implementation of foresight research within organizations. The empirical part of the study is based on the qualitative approach. A multiple case study methodology is employed. The research objects are sixteen companies experienced in foresight research. The first part of the paper gives an overview of definitions of corporate foresight and the analysis of background that have influence on the conducting of foresight in large multinational companies on one side and SMEs on the other side. In the field of the theory of foresight research, the study demonstrates that there are different motivations for foresight introduction as well as different organizational structure of teams conducting the activities and the approaches that they use. In the practical perspective, the study and a detailed functional foresight approach proposed by authors could be valuable for SMEs who consider implementing foresight research into their strategic planning processes.
-
Sequential approach to Colombeau's theory of generalized functions
International Nuclear Information System (INIS)
Todorov, T.D.
1987-07-01
J.F. Colombeau's generalized functions are constructed as equivalence classes of the elements of a specially chosen ultrapower of the class of the C ∞ -functions. The elements of this ultrapower are considered as sequences of C ∞ -functions, so in a sense, the sequential construction presented here refers to the original Colombeau theory just as, for example, the Mikusinski sequential approach to the distribution theory refers to the original Schwartz theory of distributions. The paper could be used as an elementary introduction to the Colombeau theory in which recently a solution was found to the problem of multiplication of Schwartz distributions. (author). Refs
-
Jordan, John B; Whittington, Douglas A; Bartberger, Michael D; Sickmier, E Allen; Chen, Kui; Cheng, Yuan; Judd, Ted
2016-04-28
Fragment-based drug discovery (FBDD) has become a widely used tool in small-molecule drug discovery efforts. One of the most commonly used biophysical methods in detecting weak binding of fragments is nuclear magnetic resonance (NMR) spectroscopy. In particular, FBDD performed with (19)F NMR-based methods has been shown to provide several advantages over (1)H NMR using traditional magnetization-transfer and/or two-dimensional methods. Here, we demonstrate the utility and power of (19)F-based fragment screening by detailing the identification of a second-site fragment through (19)F NMR screening that binds to a specific pocket of the aspartic acid protease, β-secretase (BACE-1). The identification of this second-site fragment allowed the undertaking of a fragment-linking approach, which ultimately yielded a molecule exhibiting a more than 360-fold increase in potency while maintaining reasonable ligand efficiency and gaining much improved selectivity over cathepsin-D (CatD). X-ray crystallographic studies of the molecules demonstrated that the linked fragments exhibited binding modes consistent with those predicted from the targeted screening approach, through-space NMR data, and molecular modeling.
-
An overview of the recent approaches for terroir functional modelling, footprinting and zoning
Vaudour, E.; Costantini, E.; Jones, G. V.; Mocali, S.
2014-11-01
Notions of terroir and their conceptualization through agri-environmental sciences have become popular in many parts of world. Originally developed for wine, terroir now encompasses many other crops including fruits, vegetables, cheese, olive oil, coffee, cacao and other crops, linking the uniqueness and quality of both beverages and foods to the environment where they are produced, giving the consumer a sense of place. Climate, geology, geomorphology, and soil are the main environmental factors which compose the terroir effect at different scales. Often considered immutable at the cultural scale, the natural components of terroir are actually a set of processes, which together create a delicate equilibrium and regulation of its effect on products in both space and time. Due to both a greater need to better understand regional to site variations in crop production and the growth in spatial analytic technologies, the study of terroir has shifted from a largely descriptive regional science to a more applied, technical research field. Furthermore, the explosion of spatial data availability and sensing technologies has made the within-field scale of study more valuable to the individual grower. The result has been greater adoption but also issues associated with both the spatial and temporal scales required for practical applications, as well as the relevant approaches for data synthesis. Moreover, as soil microbial communities are known to be of vital importance for terrestrial processes by driving the major soil geochemical cycles and supporting healthy plant growth, an intensive investigation of the microbial organization and their function is also required. Our objective is to present an overview of existing data and modelling approaches for terroir functional modelling, footprinting and zoning at local and regional scales. This review will focus on three main areas of recent terroir research: (1) quantifying the influences of terroir components on plant growth
-
Elements of a function analytic approach to probability.
Energy Technology Data Exchange (ETDEWEB)
Ghanem, Roger Georges (University of Southern California, Los Angeles, CA); Red-Horse, John Robert
2008-02-01
We first provide a detailed motivation for using probability theory as a mathematical context in which to analyze engineering and scientific systems that possess uncertainties. We then present introductory notes on the function analytic approach to probabilistic analysis, emphasizing the connections to various classical deterministic mathematical analysis elements. Lastly, we describe how to use the approach as a means to augment deterministic analysis methods in a particular Hilbert space context, and thus enable a rigorous framework for commingling deterministic and probabilistic analysis tools in an application setting.
-
Fragment approach to constrained density functional theory calculations using Daubechies wavelets
International Nuclear Information System (INIS)
Ratcliff, Laura E.; Genovese, Luigi; Mohr, Stephan; Deutsch, Thierry
2015-01-01
In a recent paper, we presented a linear scaling Kohn-Sham density functional theory (DFT) code based on Daubechies wavelets, where a minimal set of localized support functions are optimized in situ and therefore adapted to the chemical properties of the molecular system. Thanks to the systematically controllable accuracy of the underlying basis set, this approach is able to provide an optimal contracted basis for a given system: accuracies for ground state energies and atomic forces are of the same quality as an uncontracted, cubic scaling approach. This basis set offers, by construction, a natural subset where the density matrix of the system can be projected. In this paper, we demonstrate the flexibility of this minimal basis formalism in providing a basis set that can be reused as-is, i.e., without reoptimization, for charge-constrained DFT calculations within a fragment approach. Support functions, represented in the underlying wavelet grid, of the template fragments are roto-translated with high numerical precision to the required positions and used as projectors for the charge weight function. We demonstrate the interest of this approach to express highly precise and efficient calculations for preparing diabatic states and for the computational setup of systems in complex environments
-
Fragment approach to constrained density functional theory calculations using Daubechies wavelets
Energy Technology Data Exchange (ETDEWEB)
Ratcliff, Laura E., E-mail: lratcliff@anl.gov [Argonne Leadership Computing Facility, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Université de Grenoble Alpes, CEA, INAC-SP2M, L-Sim, F-38000 Grenoble (France); Genovese, Luigi; Mohr, Stephan; Deutsch, Thierry [Université de Grenoble Alpes, CEA, INAC-SP2M, L-Sim, F-38000 Grenoble (France)
2015-06-21
In a recent paper, we presented a linear scaling Kohn-Sham density functional theory (DFT) code based on Daubechies wavelets, where a minimal set of localized support functions are optimized in situ and therefore adapted to the chemical properties of the molecular system. Thanks to the systematically controllable accuracy of the underlying basis set, this approach is able to provide an optimal contracted basis for a given system: accuracies for ground state energies and atomic forces are of the same quality as an uncontracted, cubic scaling approach. This basis set offers, by construction, a natural subset where the density matrix of the system can be projected. In this paper, we demonstrate the flexibility of this minimal basis formalism in providing a basis set that can be reused as-is, i.e., without reoptimization, for charge-constrained DFT calculations within a fragment approach. Support functions, represented in the underlying wavelet grid, of the template fragments are roto-translated with high numerical precision to the required positions and used as projectors for the charge weight function. We demonstrate the interest of this approach to express highly precise and efficient calculations for preparing diabatic states and for the computational setup of systems in complex environments.
-
Extended model of restricted beam for FSO links
Poliak, Juraj; Wilfert, Otakar
2012-10-01
Modern wireless optical communication systems in many aspects overcome wire or radio communications. Their advantages are license-free operation and broad bandwidth that they offer. The medium in free-space optical (FSO) links is the atmosphere. Operation of outdoor FSO links struggles with many atmospheric phenomena that deteriorate phase and amplitude of the transmitted optical beam. This beam originates in the transmitter and is affected by its individual parts, especially by the lens socket and the transmitter aperture, where attenuation and diffraction effects take place. Both of these phenomena unfavourable influence the beam and cause degradation of link availability, or its total malfunction. Therefore, both of these phenomena should be modelled and simulated, so that one can judge the link function prior to the realization of the system. Not only the link availability and reliability are concerned, but also economic aspects. In addition, the transmitted beam is not, generally speaking, circularly symmetrical, what makes the link simulation more difficult. In a comprehensive model, it is necessary to take into account the ellipticity of the beam that is restricted by circularly symmetrical aperture where then the attenuation and diffraction occur. General model is too computationally extensive; therefore simplification of the calculations by means of analytical and numerical approaches will be discussed. Presented model is not only simulated using computer, but also experimentally proven. One can then deduce the ability of the model to describe the reality and to estimate how far can one go with approximations, i.e. limitations of the model are discussed.
-
A three-way approach for protein function classification.
Directory of Open Access Journals (Sweden)
Hafeez Ur Rehman
Full Text Available The knowledge of protein functions plays an essential role in understanding biological cells and has a significant impact on human life in areas such as personalized medicine, better crops and improved therapeutic interventions. Due to expense and inherent difficulty of biological experiments, intelligent methods are generally relied upon for automatic assignment of functions to proteins. The technological advancements in the field of biology are improving our understanding of biological processes and are regularly resulting in new features and characteristics that better describe the role of proteins. It is inevitable to neglect and overlook these anticipated features in designing more effective classification techniques. A key issue in this context, that is not being sufficiently addressed, is how to build effective classification models and approaches for protein function prediction by incorporating and taking advantage from the ever evolving biological information. In this article, we propose a three-way decision making approach which provides provisions for seeking and incorporating future information. We considered probabilistic rough sets based models such as Game-Theoretic Rough Sets (GTRS and Information-Theoretic Rough Sets (ITRS for inducing three-way decisions. An architecture of protein functions classification with probabilistic rough sets based three-way decisions is proposed and explained. Experiments are carried out on Saccharomyces cerevisiae species dataset obtained from Uniprot database with the corresponding functional classes extracted from the Gene Ontology (GO database. The results indicate that as the level of biological information increases, the number of deferred cases are reduced while maintaining similar level of accuracy.
-
Functional genomics approaches in parasitic helminths.
Hagen, J; Lee, E F; Fairlie, W D; Kalinna, B H
2012-01-01
As research on parasitic helminths is moving into the post-genomic era, an enormous effort is directed towards deciphering gene function and to achieve gene annotation. The sequences that are available in public databases undoubtedly hold information that can be utilized for new interventions and control but the exploitation of these resources has until recently remained difficult. Only now, with the emergence of methods to genetically manipulate and transform parasitic worms will it be possible to gain a comprehensive understanding of the molecular mechanisms involved in nutrition, metabolism, developmental switches/maturation and interaction with the host immune system. This review focuses on functional genomics approaches in parasitic helminths that are currently used, to highlight potential applications of these technologies in the areas of cell biology, systems biology and immunobiology of parasitic helminths. © 2011 Blackwell Publishing Ltd.
-
Ruiz, Patricia; Perlina, Ally; Mumtaz, Moiz; Fowler, Bruce A
2016-07-01
A number of epidemiological studies have identified statistical associations between persistent organic pollutants (POPs) and metabolic diseases, but testable hypotheses regarding underlying molecular mechanisms to explain these linkages have not been published. We assessed the underlying mechanisms of POPs that have been associated with metabolic diseases; three well-known POPs [2,3,7,8-tetrachlorodibenzodioxin (TCDD), 2,2´,4,4´,5,5´-hexachlorobiphenyl (PCB 153), and 4,4´-dichlorodiphenyldichloroethylene (p,p´-DDE)] were studied. We used advanced database search tools to delineate testable hypotheses and to guide laboratory-based research studies into underlying mechanisms by which this POP mixture could produce or exacerbate metabolic diseases. For our searches, we used proprietary systems biology software (MetaCore™/MetaDrug™) to conduct advanced search queries for the underlying interactions database, followed by directional network construction to identify common mechanisms for these POPs within two or fewer interaction steps downstream of their primary targets. These common downstream pathways belong to various cytokine and chemokine families with experimentally well-documented causal associations with type 2 diabetes. Our systems biology approach allowed identification of converging pathways leading to activation of common downstream targets. To our knowledge, this is the first study to propose an integrated global set of step-by-step molecular mechanisms for a combination of three common POPs using a systems biology approach, which may link POP exposure to diseases. Experimental evaluation of the proposed pathways may lead to development of predictive biomarkers of the effects of POPs, which could translate into disease prevention and effective clinical treatment strategies. Ruiz P, Perlina A, Mumtaz M, Fowler BA. 2016. A systems biology approach reveals converging molecular mechanisms that link different POPs to common metabolic diseases. Environ
-
Recurrent, robust and scalable patterns underlie human approach and avoidance.
Directory of Open Access Journals (Sweden)
Byoung Woo Kim
2010-05-01
Full Text Available Approach and avoidance behavior provide a means for assessing the rewarding or aversive value of stimuli, and can be quantified by a keypress procedure whereby subjects work to increase (approach, decrease (avoid, or do nothing about time of exposure to a rewarding/aversive stimulus. To investigate whether approach/avoidance behavior might be governed by quantitative principles that meet engineering criteria for lawfulness and that encode known features of reward/aversion function, we evaluated whether keypress responses toward pictures with potential motivational value produced any regular patterns, such as a trade-off between approach and avoidance, or recurrent lawful patterns as observed with prospect theory.Three sets of experiments employed this task with beautiful face images, a standardized set of affective photographs, and pictures of food during controlled states of hunger and satiety. An iterative modeling approach to data identified multiple law-like patterns, based on variables grounded in the individual. These patterns were consistent across stimulus types, robust to noise, describable by a simple power law, and scalable between individuals and groups. Patterns included: (i a preference trade-off counterbalancing approach and avoidance, (ii a value function linking preference intensity to uncertainty about preference, and (iii a saturation function linking preference intensity to its standard deviation, thereby setting limits to both.These law-like patterns were compatible with critical features of prospect theory, the matching law, and alliesthesia. Furthermore, they appeared consistent with both mean-variance and expected utility approaches to the assessment of risk. Ordering of responses across categories of stimuli demonstrated three properties thought to be relevant for preference-based choice, suggesting these patterns might be grouped together as a relative preference theory. Since variables in these patterns have been
-
The Link between Dietary Protein Intake, Skeletal Muscle Function and Health in Older Adults
Directory of Open Access Journals (Sweden)
Jamie I. Baum
2015-07-01
Full Text Available Skeletal muscle mass and function are progressively lost with age, a condition referred to as sarcopenia. By the age of 60, many older adults begin to be affected by muscle loss. There is a link between decreased muscle mass and strength and adverse health outcomes such as obesity, diabetes and cardiovascular disease. Data suggest that increasing dietary protein intake at meals may counterbalance muscle loss in older individuals due to the increased availability of amino acids, which stimulate muscle protein synthesis by activating the mammalian target of rapamycin (mTORC1. Increased muscle protein synthesis can lead to increased muscle mass, strength and function over time. This review aims to address the current recommended dietary allowance (RDA for protein and whether or not this value meets the needs for older adults based upon current scientific evidence. The current RDA for protein is 0.8 g/kg body weight/day. However, literature suggests that consuming protein in amounts greater than the RDA can improve muscle mass, strength and function in older adults.
-
Inference of functional properties from large-scale analysis of enzyme superfamilies.
Brown, Shoshana D; Babbitt, Patricia C
2012-01-02
As increasingly large amounts of data from genome and other sequencing projects become available, new approaches are needed to determine the functions of the proteins these genes encode. We show how large-scale computational analysis can help to address this challenge by linking functional information to sequence and structural similarities using protein similarity networks. Network analyses using three functionally diverse enzyme superfamilies illustrate the use of these approaches for facile updating and comparison of available structures for a large superfamily, for creation of functional hypotheses for metagenomic sequences, and to summarize the limits of our functional knowledge about even well studied superfamilies.
-
A review of function modeling : Approaches and applications
Erden, M.S.; Komoto, H.; Van Beek, T.J.; D'Amelio, V.; Echavarria, E.; Tomiyama, T.
2008-01-01
This work is aimed at establishing a common frame and understanding of function modeling (FM) for our ongoing research activities. A comparative review of the literature is performed to grasp the various FM approaches with their commonalities and differences. The relations of FM with the research
-
MALDI Mass Spectrometry Imaging of N-Linked Glycans in Cancer Tissues.
Drake, R R; Powers, T W; Jones, E E; Bruner, E; Mehta, A S; Angel, P M
2017-01-01
Glycosylated proteins account for a majority of the posttranslation modifications of cell surface, secreted, and circulating proteins. Within the tumor microenvironment, the presence of immune cells, extracellular matrix proteins, cell surface receptors, and interactions between stroma and tumor cells are all processes mediated by glycan binding and recognition reactions. Changes in glycosylation during tumorigenesis are well documented to occur and affect all of these associated adhesion and regulatory functions. A MALDI imaging mass spectrometry (MALDI-IMS) workflow for profiling N-linked glycan distributions in fresh/frozen tissues and formalin-fixed paraffin-embedded tissues has recently been developed. The key to the approach is the application of a molecular coating of peptide-N-glycosidase to tissues, an enzyme that cleaves asparagine-linked glycans from their protein carrier. The released N-linked glycans can then be analyzed by MALDI-IMS directly on tissue. Generally 40 or more individual glycan structures are routinely detected, and when combined with histopathology localizations, tumor-specific glycans are readily grouped relative to nontumor regions and other structural features. This technique is a recent development and new approach in glycobiology and mass spectrometry imaging research methodology; thus, potential uses such as tumor-specific glycan biomarker panels and other applications are discussed. © 2017 Elsevier Inc. All rights reserved.
-
Catrambone, Richard; Gerjets, Peter; Scheiter, Katharina; Vollmann, Brigitte
2006-01-01
Literature reviews on hypermedia learning have yet failed to show consistent positive effects of learner-controlled nonlinear information access. We argue that a possible reason for this lack of evidence in favor of hypermedia learning results from the fact that not sufficient attention is paid to the strategies of information utilization learners deploy. The few studies that do analyze these strategies fail to link them to an instructional approach, which hampers a deeper interpretation of s...
-
Raj Kumar Chopra; Varun Gupta; Durg Singh Chauhan
2016-01-01
Non functional requirements must be selected for implementation together with functional requirements to enhance the success of software projects. Three approaches exist for performing the prioritization of non functional requirements using the suitable prioritization technique. This paper performs experimentation on three different complexity versions of the industrial software project using cost-value prioritization technique employing three approaches. Experimentation is conducted to analy...
-
Fuzzy set approach to quality function deployment: An investigation
Masud, Abu S. M.
1992-01-01
The final report of the 1992 NASA/ASEE Summer Faculty Fellowship at the Space Exploration Initiative Office (SEIO) in Langley Research Center is presented. Quality Function Deployment (QFD) is a process, focused on facilitating the integration of the customer's voice in the design and development of a product or service. Various input, in the form of judgements and evaluations, are required during the QFD analyses. All the input variables in these analyses are treated as numeric variables. The purpose of the research was to investigate how QFD analyses can be performed when some or all of the input variables are treated as linguistic variables with values expressed as fuzzy numbers. The reason for this consideration is that human judgement, perception, and cognition are often ambiguous and are better represented as fuzzy numbers. Two approaches for using fuzzy sets in QFD have been proposed. In both cases, all the input variables are considered as linguistic variables with values indicated as linguistic expressions. These expressions are then converted to fuzzy numbers. The difference between the two approaches is due to how the QFD computations are performed with these fuzzy numbers. In Approach 1, the fuzzy numbers are first converted to their equivalent crisp scores and then the QFD computations are performed using these crisp scores. As a result, the output of this approach are crisp numbers, similar to those in traditional QFD. In Approach 2, all the QFD computations are performed with the fuzzy numbers and the output are fuzzy numbers also. Both the approaches have been explained with the help of illustrative examples of QFD application. Approach 2 has also been applied in a QFD application exercise in SEIO, involving a 'mini moon rover' design. The mini moon rover is a proposed tele-operated vehicle that will traverse and perform various tasks, including autonomous operations, on the moon surface. The output of the moon rover application exercise is a
-
Automatic discovery of cross-family sequence features associated with protein function
Directory of Open Access Journals (Sweden)
Krings Andrea
2006-01-01
Full Text Available Abstract Background Methods for predicting protein function directly from amino acid sequences are useful tools in the study of uncharacterised protein families and in comparative genomics. Until now, this problem has been approached using machine learning techniques that attempt to predict membership, or otherwise, to predefined functional categories or subcellular locations. A potential drawback of this approach is that the human-designated functional classes may not accurately reflect the underlying biology, and consequently important sequence-to-function relationships may be missed. Results We show that a self-supervised data mining approach is able to find relationships between sequence features and functional annotations. No preconceived ideas about functional categories are required, and the training data is simply a set of protein sequences and their UniProt/Swiss-Prot annotations. The main technical aspect of the approach is the co-evolution of amino acid-based regular expressions and keyword-based logical expressions with genetic programming. Our experiments on a strictly non-redundant set of eukaryotic proteins reveal that the strongest and most easily detected sequence-to-function relationships are concerned with targeting to various cellular compartments, which is an area already well studied both experimentally and computationally. Of more interest are a number of broad functional roles which can also be correlated with sequence features. These include inhibition, biosynthesis, transcription and defence against bacteria. Despite substantial overlaps between these functions and their corresponding cellular compartments, we find clear differences in the sequence motifs used to predict some of these functions. For example, the presence of polyglutamine repeats appears to be linked more strongly to the "transcription" function than to the general "nuclear" function/location. Conclusion We have developed a novel and useful approach for
-
Lee, Hanleem; Bak, Sora; An, Sung-Jin; Kim, Jung Ho; Yun, Eunbhin; Kim, Meeree; Seo, Sohyeon; Jeong, Mun Seok; Lee, Hyoyoung
2017-12-26
Thin-film transistors (TFTs) have received great attention for their use in lightweight, large area, and wearable devices. However, low crystalline materials and inhomogeneous film formation limit the realization of high-quality electrical properties for channels in commercial TFTs, especially for flexible electronics. Here, we report a field-effect TFT fabricated via cross-linking of edge-1T basal-2H MoS 2 sheets that are prepared by edge functional exfoliation of bulk MoS 2 with soft organic exfoliation reagents. For edge functional exfoliation, the electrophilic 4-carboxy-benzenediazonium used as the soft organic reagent attacks the nucleophilic thiolates exposed at the edge of the bulk MoS 2 with the help of an amine catalyst, resulting in 1T edge-functional HOOC-benzene-2H basal MoS 2 nanosheets (e-MoS 2 ). The cross-linking via hydrogen bonding of the negatively charged HOOC of the e-MoS 2 sheets with the help of a cationic polymer, polydiallyldimethylammonium chloride, results in a good film formation for a channel of the solution processing TFT. The TFT exhibits an extremely high mobility of 170 cm 2 /(V s) at 1 V (on/off ratio of 10 6 ) on SiO 2 /Si substrate and also a high mobility of 36.34 cm 2 /(V s) (on/off ratio of 10 3 ) on PDMS/PET substrate.
-
Wan, Cen; Lees, Jonathan G; Minneci, Federico; Orengo, Christine A; Jones, David T
2017-10-01
Accurate gene or protein function prediction is a key challenge in the post-genome era. Most current methods perform well on molecular function prediction, but struggle to provide useful annotations relating to biological process functions due to the limited power of sequence-based features in that functional domain. In this work, we systematically evaluate the predictive power of temporal transcription expression profiles for protein function prediction in Drosophila melanogaster. Our results show significantly better performance on predicting protein function when transcription expression profile-based features are integrated with sequence-derived features, compared with the sequence-derived features alone. We also observe that the combination of expression-based and sequence-based features leads to further improvement of accuracy on predicting all three domains of gene function. Based on the optimal feature combinations, we then propose a novel multi-classifier-based function prediction method for Drosophila melanogaster proteins, FFPred-fly+. Interpreting our machine learning models also allows us to identify some of the underlying links between biological processes and developmental stages of Drosophila melanogaster.
-
Directory of Open Access Journals (Sweden)
Cen Wan
2017-10-01
Full Text Available Accurate gene or protein function prediction is a key challenge in the post-genome era. Most current methods perform well on molecular function prediction, but struggle to provide useful annotations relating to biological process functions due to the limited power of sequence-based features in that functional domain. In this work, we systematically evaluate the predictive power of temporal transcription expression profiles for protein function prediction in Drosophila melanogaster. Our results show significantly better performance on predicting protein function when transcription expression profile-based features are integrated with sequence-derived features, compared with the sequence-derived features alone. We also observe that the combination of expression-based and sequence-based features leads to further improvement of accuracy on predicting all three domains of gene function. Based on the optimal feature combinations, we then propose a novel multi-classifier-based function prediction method for Drosophila melanogaster proteins, FFPred-fly+. Interpreting our machine learning models also allows us to identify some of the underlying links between biological processes and developmental stages of Drosophila melanogaster.
-
Graph-based sequence annotation using a data integration approach
Directory of Open Access Journals (Sweden)
Pesch Robert
2008-06-01
Full Text Available The automated annotation of data from high throughput sequencing and genomics experiments is a significant challenge for bioinformatics. Most current approaches rely on sequential pipelines of gene finding and gene function prediction methods that annotate a gene with information from different reference data sources. Each function prediction method contributes evidence supporting a functional assignment. Such approaches generally ignore the links between the information in the reference datasets. These links, however, are valuable for assessing the plausibility of a function assignment and can be used to evaluate the confidence in a prediction. We are working towards a novel annotation system that uses the network of information supporting the function assignment to enrich the annotation process for use by expert curators and predicting the function of previously unannotated genes. In this paper we describe our success in the first stages of this development. We present the data integration steps that are needed to create the core database of integrated reference databases (UniProt, PFAM, PDB, GO and the pathway database Ara- Cyc which has been established in the ONDEX data integration system. We also present a comparison between different methods for integration of GO terms as part of the function assignment pipeline and discuss the consequences of this analysis for improving the accuracy of gene function annotation.
-
Directory of Open Access Journals (Sweden)
Luiz Augusto da Cruz Meleiro
2005-06-01
Full Text Available In this work a MIMO non-linear predictive controller was developed for an extractive alcoholic fermentation process. The internal model of the controller was represented by two MISO Functional Link Networks (FLNs, identified using simulated data generated from a deterministic mathematical model whose kinetic parameters were determined experimentally. The FLN structure presents as advantages fast training and guaranteed convergence, since the estimation of the weights is a linear optimization problem. Besides, the elimination of non-significant weights generates parsimonious models, which allows for fast execution in an MPC-based algorithm. The proposed algorithm showed good potential in identification and control of non-linear processes.Neste trabalho um controlador preditivo não linear multivariável foi desenvolvido para um processo de fermentação alcoólica extrativa. O modelo interno do controlador foi representado por duas redes do tipo Functional Link (FLN, identificadas usando dados de simulação gerados a partir de um modelo validado experimentalmente. A estrutura FLN apresenta como vantagem o treinamento rápido e convergência garantida, já que a estimação dos seus pesos é um problema de otimização linear. Além disso, a eliminação de pesos não significativos gera modelos parsimoniosos, o que permite a rápida execução em algoritmos de controle preditivo baseado em modelo. Os resultados mostram que o algoritmo proposto tem grande potencial para identificação e controle de processos não lineares.
-
Cost function approach for estimating derived demand for composite wood products
T. C. Marcin
1991-01-01
A cost function approach was examined for using the concept of duality between production and input factor demands. A translog cost function was used to represent residential construction costs and derived conditional factor demand equations. Alternative models were derived from the translog cost function by imposing parameter restrictions.
-
Badiola, Iker; Santaolalla, Francisco; Garcia-Gallastegui, Patricia; Ana, Sánchez-Del Rey; Unda, Fernando; Ibarretxe, Gaskon
2015-09-01
Human ageing is associated with a gradual decline in the physiological functions of the body at multiple levels and it is a key risk factor for many diseases, including cancer. Ageing process is intimately related to widespread cellular senescence, characterised by an irreversible loss of proliferative capacity and altered functioning associated with telomere attrition, accumulation of DNA damage and compromised mitochondrial and metabolic function. Tumour and senescent cells may be generated in response to the same stimuli, where either cellular senescence or transformation would constitute two opposite outcomes of the same degenerative process. This paper aims to review the state of knowledge on the biomolecular relationship between cellular senescence, ageing and cancer. Importantly, many of the cell signalling pathways that are found to be altered during both cellular senescence and tumourigenesis are regulated through shared epigenetic mechanisms and, therefore, they are potentially reversible. MicroRNAs are emerging as pivotal players linking ageing and cancer. These small RNA molecules have generated great interest from the point of view of future clinical therapy for cancer because successful experimental results have been obtained in animal models. Micro-RNA therapies for cancer are already being tested in clinical phase trials. These findings have potential importance in cancer treatment in aged people although further research-based knowledge is needed to convert them into an effective molecular therapies for cancer linked to ageing. Copyright © 2015 Elsevier B.V. All rights reserved.
-
Identification of hybrid node and link communities in complex networks.
He, Dongxiao; Jin, Di; Chen, Zheng; Zhang, Weixiong
2015-03-02
Identifying communities in complex networks is an effective means for analyzing complex systems, with applications in diverse areas such as social science, engineering, biology and medicine. Finding communities of nodes and finding communities of links are two popular schemes for network analysis. These schemes, however, have inherent drawbacks and are inadequate to capture complex organizational structures in real networks. We introduce a new scheme and an effective approach for identifying complex mixture structures of node and link communities, called hybrid node-link communities. A central piece of our approach is a probabilistic model that accommodates node, link and hybrid node-link communities. Our extensive experiments on various real-world networks, including a large protein-protein interaction network and a large network of semantically associated words, illustrated that the scheme for hybrid communities is superior in revealing network characteristics. Moreover, the new approach outperformed the existing methods for finding node or link communities separately.
-
Identification of hybrid node and link communities in complex networks
He, Dongxiao; Jin, Di; Chen, Zheng; Zhang, Weixiong
2015-03-01
Identifying communities in complex networks is an effective means for analyzing complex systems, with applications in diverse areas such as social science, engineering, biology and medicine. Finding communities of nodes and finding communities of links are two popular schemes for network analysis. These schemes, however, have inherent drawbacks and are inadequate to capture complex organizational structures in real networks. We introduce a new scheme and an effective approach for identifying complex mixture structures of node and link communities, called hybrid node-link communities. A central piece of our approach is a probabilistic model that accommodates node, link and hybrid node-link communities. Our extensive experiments on various real-world networks, including a large protein-protein interaction network and a large network of semantically associated words, illustrated that the scheme for hybrid communities is superior in revealing network characteristics. Moreover, the new approach outperformed the existing methods for finding node or link communities separately.
-
A comprehensive comparison of network similarities for link prediction and spurious link elimination
Zhang, Peng; Qiu, Dan; Zeng, An; Xiao, Jinghua
2018-06-01
Identifying missing interactions in complex networks, known as link prediction, is realized by estimating the likelihood of the existence of a link between two nodes according to the observed links and nodes' attributes. Similar approaches have also been employed to identify and remove spurious links in networks which is crucial for improving the reliability of network data. In network science, the likelihood for two nodes having a connection strongly depends on their structural similarity. The key to address these two problems thus becomes how to objectively measure the similarity between nodes in networks. In the literature, numerous network similarity metrics have been proposed and their accuracy has been discussed independently in previous works. In this paper, we systematically compare the accuracy of 18 similarity metrics in both link prediction and spurious link elimination when the observed networks are very sparse or consist of inaccurate linking information. Interestingly, some methods have high prediction accuracy, they tend to perform low accuracy in identification spurious interaction. We further find that methods can be classified into several cluster according to their behaviors. This work is useful for guiding future use of these similarity metrics for different purposes.
-
A New Approach for Predicting the Variance of Random Decrement Functions
DEFF Research Database (Denmark)
Asmussen, J. C.; Brincker, Rune
mean Gaussian distributed processes the RD functions are proportional to the correlation functions of the processes. If a linear structur is loaded by Gaussian white noise the modal parameters can be extracted from the correlation funtions of the response, only. One of the weaknesses of the RD...... technique is that no consistent approach to estimate the variance of the RD functions is known. Only approximate relations are available, which can only be used under special conditions. The variance of teh RD functions contains valuable information about accuracy of the estimates. Furthermore, the variance...... can be used as basis for a decision about how many time lags from the RD funtions should be used in the modal parameter extraction procedure. This paper suggests a new method for estimating the variance of the RD functions. The method is consistent in the sense that the accuracy of the approach...
-
A New Approach for Predicting the Variance of Random Decrement Functions
DEFF Research Database (Denmark)
Asmussen, J. C.; Brincker, Rune
1998-01-01
mean Gaussian distributed processes the RD functions are proportional to the correlation functions of the processes. If a linear structur is loaded by Gaussian white noise the modal parameters can be extracted from the correlation funtions of the response, only. One of the weaknesses of the RD...... technique is that no consistent approach to estimate the variance of the RD functions is known. Only approximate relations are available, which can only be used under special conditions. The variance of teh RD functions contains valuable information about accuracy of the estimates. Furthermore, the variance...... can be used as basis for a decision about how many time lags from the RD funtions should be used in the modal parameter extraction procedure. This paper suggests a new method for estimating the variance of the RD functions. The method is consistent in the sense that the accuracy of the approach...
-
Strategic approach to outsourcing the research and development function
Firend, A.R
2010-01-01
This paper proposes an approach for outsourcing the R&D function. This model is to serve as a strategic approach to outsourcing that considers number of elements with strategic competitive advantage as an ultimate objective. This paper suggest that outsourcing research and development should be planed and conducted from a strategic standpoint and have positive impact on organizational competitive position by incorporating it into the overall\\ud strategy of the organization to reduce the numbe...
-
Production and Consumption of University Linked Data
Zablith, Fouad; Fernandez, Miriam; Rowe, Matthew
2015-01-01
Linked Data increases the value of an organisation's data over the web by introducing explicit and machine processable links at the data level. We have adopted this new stream of data representation to produce and expose existing data within The Open University (OU) as Linked Data. We present in this paper our approach for producing the data,…
-
A novel approach to error function minimization for feedforward neural networks
International Nuclear Information System (INIS)
Sinkus, R.
1995-01-01
Feedforward neural networks with error backpropagation are widely applied to pattern recognition. One general problem encountered with this type of neural networks is the uncertainty, whether the minimization procedure has converged to a global minimum of the cost function. To overcome this problem a novel approach to minimize the error function is presented. It allows to monitor the approach to the global minimum and as an outcome several ambiguities related to the choice of free parameters of the minimization procedure are removed. (orig.)
-
Gueron-Sela, Noa; Bedford, Rachael; Wagner, Nicholas J; Propper, Cathi B
2017-10-20
The goal of this study was to examine the independent and interactive roles of harsh-intrusive maternal behaviors and children's executive function in the development of internalizing behaviors across the first years of school. A diverse sample (58% African American, 42% European American) of 137 children (48% female) was followed from kindergarten (age 5 years) through school entry (ages 6-7 years). At age 5, maternal harsh-intrusive parenting behaviors were rated from a mother-child structured play task, and children completed 3 executive function tasks that measured inhibitory control, working memory, and attention set-shifting. Teachers reported on children's internalizing behaviors at ages 5, 6, and 7. Harsh-intrusive parenting behaviors at age 5 years were positively related to internalizing behaviors in the first years of school, whereas high executive function abilities at age 5 years were related to lower internalizing behaviors in the first years of school. In addition, executive function buffered the association between parenting behaviors and internalizing behaviors such that the link between harsh-intrusive parenting and child internalizing behaviors was evident only among children with low executive function and not among children with high executive function. Interventions that focus on reducing negative parenting behaviors and improving children's executive function may prevent internalizing behaviors from increasing during times of social and academic challenge.
-
Integration a functional approach
Bichteler, Klaus
1998-01-01
This book covers Lebesgue integration and its generalizations from Daniell's point of view, modified by the use of seminorms. Integrating functions rather than measuring sets is posited as the main purpose of measure theory. From this point of view Lebesgue's integral can be had as a rather straightforward, even simplistic, extension of Riemann's integral; and its aims, definitions, and procedures can be motivated at an elementary level. The notion of measurability, for example, is suggested by Littlewood's observations rather than being conveyed authoritatively through definitions of (sigma)-algebras and good-cut-conditions, the latter of which are hard to justify and thus appear mysterious, even nettlesome, to the beginner. The approach taken provides the additional benefit of cutting the labor in half. The use of seminorms, ubiquitous in modern analysis, speeds things up even further. The book is intended for the reader who has some experience with proofs, a beginning graduate student for example. It might...
-
DEFF Research Database (Denmark)
Bælum, Jacob; Chambon, Julie Claire Claudia; Scheutz, Charlotte
2013-01-01
We used current knowledge of cellular processes involved in reductive dechlorination to develop a conceptual model to describe the regulatory system of dechlorination at the cell level; the model links bacterial growth and substrate consumption to the abundance of messenger RNA of functional gene...
-
International Nuclear Information System (INIS)
Hupin, G; Lacroix, D; Bender, M
2011-01-01
The Multi-Reference Energy Density Functional (MR-EDF) approach (also called configuration mixing or Generator Coordinate Method), that is commonly used to treat pairing in finite nuclei and project onto particle number, is re-analyzed. It is shown that, under certain conditions, the MR-EDF energy can be interpreted as a functional of the one-body density matrix of the projected state with good particle number. Based on this observation, we propose a new approach, called Symmetry-Conserving EDF (SC-EDF), where the breaking and restoration of symmetry are accounted for simultaneously. We show, that such an approach is free from pathologies recently observed in MR-EDF and can be used with a large flexibility on the density dependence of the functional.
-
Phenotypic and functional characterization of earthworm coelomocyte subsets
DEFF Research Database (Denmark)
Engelmann, Péter; Hayashi, Yuya; Bodo, Kornélia
2016-01-01
Flow cytometry is a common approach to study invertebrate immune cells including earthworm coelomocytes. However, the link between light-scatter- and microscopy-based phenotyping remains obscured. Here we show, by means of light scatter-based cell sorting, both subpopulations (amoebocytes...... amoebocytes and eleocytes, with the former being in favor of bacterial engulfment. This study has proved successful in linking flow cytometry and microscopy analysis and provides further experimental evidence of phenotypic and functional heterogeneity in earthworm coelomocyte subsets....
-
A Genomic Map of the Effects of Linked Selection in Drosophila.
Directory of Open Access Journals (Sweden)
Eyal Elyashiv
2016-08-01
Full Text Available Natural selection at one site shapes patterns of genetic variation at linked sites. Quantifying the effects of "linked selection" on levels of genetic diversity is key to making reliable inference about demography, building a null model in scans for targets of adaptation, and learning about the dynamics of natural selection. Here, we introduce the first method that jointly infers parameters of distinct modes of linked selection, notably background selection and selective sweeps, from genome-wide diversity data, functional annotations and genetic maps. The central idea is to calculate the probability that a neutral site is polymorphic given local annotations, substitution patterns, and recombination rates. Information is then combined across sites and samples using composite likelihood in order to estimate genome-wide parameters of distinct modes of selection. In addition to parameter estimation, this approach yields a map of the expected neutral diversity levels along the genome. To illustrate the utility of our approach, we apply it to genome-wide resequencing data from 125 lines in Drosophila melanogaster and reliably predict diversity levels at the 1Mb scale. Our results corroborate estimates of a high fraction of beneficial substitutions in proteins and untranslated regions (UTR. They allow us to distinguish between the contribution of sweeps and other modes of selection around amino acid substitutions and to uncover evidence for pervasive sweeps in untranslated regions (UTRs. Our inference further suggests a substantial effect of other modes of linked selection and of adaptation in particular. More generally, we demonstrate that linked selection has had a larger effect in reducing diversity levels and increasing their variance in D. melanogaster than previously appreciated.
-
A Genomic Map of the Effects of Linked Selection in Drosophila.
Elyashiv, Eyal; Sattath, Shmuel; Hu, Tina T; Strutsovsky, Alon; McVicker, Graham; Andolfatto, Peter; Coop, Graham; Sella, Guy
2016-08-01
Natural selection at one site shapes patterns of genetic variation at linked sites. Quantifying the effects of "linked selection" on levels of genetic diversity is key to making reliable inference about demography, building a null model in scans for targets of adaptation, and learning about the dynamics of natural selection. Here, we introduce the first method that jointly infers parameters of distinct modes of linked selection, notably background selection and selective sweeps, from genome-wide diversity data, functional annotations and genetic maps. The central idea is to calculate the probability that a neutral site is polymorphic given local annotations, substitution patterns, and recombination rates. Information is then combined across sites and samples using composite likelihood in order to estimate genome-wide parameters of distinct modes of selection. In addition to parameter estimation, this approach yields a map of the expected neutral diversity levels along the genome. To illustrate the utility of our approach, we apply it to genome-wide resequencing data from 125 lines in Drosophila melanogaster and reliably predict diversity levels at the 1Mb scale. Our results corroborate estimates of a high fraction of beneficial substitutions in proteins and untranslated regions (UTR). They allow us to distinguish between the contribution of sweeps and other modes of selection around amino acid substitutions and to uncover evidence for pervasive sweeps in untranslated regions (UTRs). Our inference further suggests a substantial effect of other modes of linked selection and of adaptation in particular. More generally, we demonstrate that linked selection has had a larger effect in reducing diversity levels and increasing their variance in D. melanogaster than previously appreciated.
-
AN ENERGY FUNCTION APPROACH FOR FINDING ROOTS OF CHARACTERISTIC EQUATION
Deepak Mishra; Prem K. Kalra
2011-01-01
In this paper, an energy function approach for finding roots of a characteristic equation has been proposed. Finding the roots of a characteristics equation is considered as an optimization problem. We demonstrated that this problem can be solved with the application of feedback type neural network. The proposed approach is fast and robust against variation of parameter.
-
Khare, Ketan S; Khabaz, Fardin; Khare, Rajesh
2014-05-14
We have used amido-amine functionalized carbon nanotubes (CNTs) that form covalent bonds with cross-linked epoxy matrices to elucidate the role of the matrix-filler interphase in the enhancement of mechanical and thermal properties in these nanocomposites. For the base case of nanocomposites of cross-linked epoxy and pristine single-walled CNTs, our previous work (Khare, K. S.; Khare, R. J. Phys. Chem. B 2013, 117, 7444-7454) has shown that weak matrix-filler interactions cause the interphase region in the nanocomposite to be more compressible. Furthermore, because of the weak matrix-filler interactions, the nanocomposite containing dispersed pristine CNTs has a glass transition temperature (Tg) that is ∼66 K lower than the neat polymer. In this work, we demonstrate that in spite of the presence of stiff CNTs in the nanocomposite, the Young's modulus of the nanocomposite containing dispersed pristine CNTs is virtually unchanged compared to the neat cross-linked epoxy. This observation suggests that the compressibility of the matrix-filler interphase interferes with the ability of the CNTs to reinforce the matrix. Furthermore, when the compressibility of the interphase is reduced by the use of amido-amine functionalized CNTs, the mechanical reinforcement due to the filler is more effective, resulting in a ∼50% increase in the Young's modulus compared to the neat cross-linked epoxy. Correspondingly, the functionalization of the CNTs also led to a recovery in the Tg making it effectively the same as the neat polymer and also resulted in a ∼12% increase in the thermal conductivity of the nanocomposite containing functionalized CNTs compared to that containing pristine CNTs. These results demonstrate that the functionalization of the CNTs facilitates the transfer of both mechanical load and thermal energy across the matrix-filler interface.
-
DEFF Research Database (Denmark)
Nielsen, Steen; Nielsen, Erland Hejn
Review, July-August, 2007], provide evidence that companies fail to see the possible benefits of combining and integrating several accounting practices into a single framework. Design/methodology/approach - We use a System Dynamics Modelling approach to the BSC-thinking. The BSC model includes the five...... Purpose - To show how three practices normally applied separately can be linked to support the strategy evaluation and the performance measurement in the balanced scorecard. Recent studies, e.g. Kaplan and Norton [Using the Balanced Scorecard as a Strategic Management System, Harvard Business...
-
Wallops' Low Elevation Link Analysis for the Constellation Launch/Ascent Links
Cheung, Kar-Ming; Ho, Christian; Kantak, Anil; Lee, Charles; Tye, Robert; Richards, Edger; Sham, Catherine; Schlesinger, Adam; Barritt, Brian
2011-01-01
Prior to the redirection of the Constellation Program, the Wallops 11.3-meter ground station was tasked to support the Orion's Dissimilar Voice (DV) link and the Ares's Development Flight Instrument (DFI) link. Detailed analysis of the launch trajectories indicates that during the launch and ascent operation, the critical events of Orion-Ares main engine cut off (MECO) and Separation occur at low elevation angle. We worked with engineers from both Wallops Flight Facility (WFF) and Johnson Space Center (JSC) to perform an intensive measurement and link analysis campaign on the DV and DFI links. The main results were as follows: (1) The DV links have more than 3 dB margin at MECO and Separation. (2) The DFI links have 0 dB margin at Separation during certain weather condition in summer season. (3) Tropospheric scintillation loss is the major impairment at low elevation angle. (4) The current scintillation models in the Recommendation ITU-R P.618 (Propagation data and prediction methods required for the design of Earth-space telecommunication systems), which are based on limited experimental and theoretical work, exhibit idiosyncratic behaviors. We developed an improved model based on the measurements of recent Shuttle mission launch and ascent links and the ITU propagation data. (5) Due to the attitude uncertainty of the Orion-Ares stack, the high dynamics of the launch and ascent trajectory, and the irregularity of the Orion and Ares antenna patterns, we employed new link analysis approach to model the spacecraft antenna gain. In this paper we discuss the details of the aforementioned results.
-
Utility-Based Link Recommendation in Social Networks
Li, Zhepeng
2013-01-01
Link recommendation, which suggests links to connect currently unlinked users, is a key functionality offered by major online social networking platforms. Salient examples of link recommendation include "people you may know"' on Facebook and "who to follow" on Twitter. A social networking platform has two types of stakeholder:…
-
Ibrahim, Jeyda; Cosgrave, Nicola; Woolgar, Matthew
2018-01-01
Borderline personality disorder has repeatedly been associated with a history of maltreatment in childhood; however, research on maltreatment and its link to borderline features in children is limited. The aim of this review is to synthesise the existing data on the association between maltreatment and borderline features in childhood. In total, 10 studies were included in this systematic review. Studies indicated that children with borderline features were more likely to have a history of maltreatment, and that children who had been maltreated were more likely to present with borderline features. Other risk factors such as cognitive and executive functioning deficits, parental dysfunction and genetic vulnerability were also identified across studies. This review adds to the literature by highlighting maltreatment as a risk factor for borderline features in childhood. Longitudinal research is required to establish the link between childhood borderline features and adult borderline features. Implications for early identification, prevention and intervention services are discussed.
-
International Nuclear Information System (INIS)
Zalialiutdinov, T; Baukina, Yu; Solovyev, D; Labzowsky, L
2014-01-01
The theory of multiphoton cascade transitions with two-photon links is considered within two different approaches: quantum electrodynamical (QED) and phenomenological quantum mechanical (QM). A problem of regularization of the cascade contributions is investigated in detail. It is argued that the correct regularization should include both initial and intermediate level widths in the singular energy denominators. This result follows both from the QED and from the QM approach. Particular transitions nl → 1s + 2γ with nl = 3s, 4s, 3d, 4d and nl → 1s + 3γ with nl = 3p, 4p are considered as examples. The importance of the proper cascade regularization is also demonstrated. (paper)
-
Functional approach in estimation of cultural ecosystem services of recreational areas
Sautkin, I. S.; Rogova, T. V.
2018-01-01
The article is devoted to the identification and analysis of cultural ecosystem services of recreational areas from the different forest plant functional groups in the suburbs of Kazan. The study explored two cultural ecosystem services supplied by forest plants by linking these services to different plant functional traits. Information on the functional traits of 76 plants occurring in the forest ecosystems of the investigated area was collected from reference books on the biological characteristics of plant species. Analysis of these species and traits with the Ward clustering method yielded four functional groups with different potentials for delivering ecosystem services. The results show that the contribution of species diversity to services can be characterized through the functional traits of plants. This proves that there is a stable relationship between biodiversity and the quality and quantity of ecosystem services. The proposed method can be extended to other types of services (regulating and supporting). The analysis can be used in the socio-economic assessment of natural ecosystems for recreation and other uses.
-
Links between circadian rhythms and psychiatric disease
Directory of Open Access Journals (Sweden)
Ilia N Karatsoreos
2014-05-01
Full Text Available Determining the cause of psychiatric disorders is a goal of modern neuroscience, and will hopefully lead to the discovery of treatments to either prevent or alleviate the suffering caused by these diseases. One roadblock to attaining this goal is the realization that neuropsychiatric diseases are rarely due to a single gene polymorphism, environmental exposure, or developmental insult. Rather, it is a complex interaction between these various influences that likely leads to the development of clinically relevant syndromes. Our lab is exploring the links between environmental exposures and neurobehavioral function by investigating how disruption of the circadian (daily clock alters the structure and function of neural circuits, with the hypothesis that disrupting this crucial homeostatic system can directly contribute to altered vulnerability of the organism to other factors that interact to produce psychiatric illness. This review explores some historical and more recent findings that link disrupted circadian clocks to neuropsychiatric disorders, particularly depression, mania, and schizophrenia. We take a comparative approach by exploring the effects observed in human populations, as well as some experimental models used in the laboratory to unravel mechanistic and causal relationships between disruption of the circadian clock and behavioral abnormalities. This is a rich area of research that we predict will contribute greatly to our understanding of how genes, environment, and development interact to modulate an individual’s vulnerability to psychiatric disorders.
-
Engel, Annette Summers; Meisinger, Daniela B; Porter, Megan L; Payn, Robert A; Schmid, Michael; Stern, Libby A; Schleifer, K H; Lee, Natuschka M
2010-01-01
Microbial mats in sulfidic cave streams offer unique opportunities to study redox-based biogeochemical nutrient cycles. Previous work from Lower Kane Cave, Wyoming, USA, focused on the aerobic portion of microbial mats, dominated by putative chemolithoautotrophic, sulfur-oxidizing groups within the Epsilonproteobacteria and Gammaproteobacteria. To evaluate nutrient cycling and turnover within the whole mat system, a multidisciplinary strategy was used to characterize the anaerobic portion of the mats, including application of the full-cycle rRNA approach, the most probable number method, and geochemical and isotopic analyses. Seventeen major taxonomic bacterial groups and one archaeal group were retrieved from the anaerobic portions of the mats, dominated by Deltaproteobacteria and uncultured members of the Chloroflexi phylum. A nutrient spiraling model was applied to evaluate upstream to downstream changes in microbial diversity based on carbon and sulfur nutrient concentrations. Variability in dissolved sulfide concentrations was attributed to changes in the abundance of sulfide-oxidizing microbial groups and shifts in the occurrence and abundance of sulfate-reducing microbes. Gradients in carbon and sulfur isotopic composition indicated that released and recycled byproduct compounds from upstream microbial activities were incorporated by downstream communities. On the basis of the type of available chemical energy, the variability of nutrient species in a spiraling model may explain observed differences in microbial taxonomic affiliations and metabolic functions, thereby spatially linking microbial diversity to nutrient spiraling in the cave stream ecosystem.
-
Tse, Maric T; Piantadosi, Patrick T; Floresco, Stan B
2015-06-01
Cognitive dysfunction in schizophrenia is one of the most pervasive and debilitating aspects of the disorder. Among the numerous neural abnormalities that may contribute to schizophrenia symptoms, perturbations in markers for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), particularly within the frontal lobes, are some of the most reliable alterations observed at postmortem examination. However, how prefrontal GABA dysfunction contributes to cognitive impairment in schizophrenia remains unclear. We provide an overview of postmortem GABAergic perturbations in the brain affected by schizophrenia and describe circumstantial evidence linking these alterations to cognitive dysfunction. In addition, we conduct a survey of studies using neurodevelopmental, genetic, and pharmacologic rodent models that induce schizophrenia-like cognitive impairments, highlighting the convergence of these mechanistically distinct approaches to prefrontal GABAergic disruption. We review preclinical studies that have directly targeted prefrontal cortical GABAergic transmission using local application of GABAA receptor antagonists. These studies have provided an important link between GABA transmission and cognitive dysfunction in schizophrenia because they show that reducing prefrontal inhibitory transmission induces various cognitive, emotional, and dopaminergic abnormalities that resemble aspects of the disorder. These converging clinical and preclinical findings provide strong support for the idea that perturbations in GABA signaling drive certain forms of cognitive dysfunction in schizophrenia. Future studies using this approach will yield information to refine further a putative "GABA hypothesis" of schizophrenia. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
-
Multifunctional fiber-optic microwave links based on remote heterodyne detection
DEFF Research Database (Denmark)
Gliese, Ulrik Bo; Nielsen, Torben Nørskov; Nielsen, Søren Nørskov
1998-01-01
The multifunctionality of microwave links based on remote heterodyne detection (RHD) of signals from a dual-frequency laser transmitter is discussed and experimentally demonstrated in this paper. Typically, direct detection (DD) in conjunction with optical intensity modulation is used to implement...... fiber-optic microwave links. The resulting links are inherently transparent. As opposed to DD links, RHD links can perform radio-system functionalities such as modulation and frequency conversion in addition to transparency. All of these three functionalities are presented and experimentally...
-
Akçakin, Veysel
2018-01-01
The purpose of this study is to investigate the effects of using geometric functions approach on 9th grade students' motivation levels toward mathematics in functions unit. Participants of this study were 87 students who were ongoing in the first year of high school in Turkey. In this research, pretest and posttest control group quasiexperimental…
-
Positive selection in octopus haemocyanin indicates functional links to temperature adaptation.
Oellermann, Michael; Strugnell, Jan M; Lieb, Bernhard; Mark, Felix C
2015-07-05
Octopods have successfully colonised the world's oceans from the tropics to the poles. Yet, successful persistence in these habitats has required adaptations of their advanced physiological apparatus to compensate impaired oxygen supply. Their oxygen transporter haemocyanin plays a major role in cold tolerance and accordingly has undergone functional modifications to sustain oxygen release at sub-zero temperatures. However, it remains unknown how molecular properties evolved to explain the observed functional adaptations. We thus aimed to assess whether natural selection affected molecular and structural properties of haemocyanin that explains temperature adaptation in octopods. Analysis of 239 partial sequences of the haemocyanin functional units (FU) f and g of 28 octopod species of polar, temperate, subtropical and tropical origin revealed natural selection was acting primarily on charge properties of surface residues. Polar octopods contained haemocyanins with higher net surface charge due to decreased glutamic acid content and higher numbers of basic amino acids. Within the analysed partial sequences, positive selection was present at site 2545, positioned between the active copper binding centre and the FU g surface. At this site, methionine was the dominant amino acid in polar octopods and leucine was dominant in tropical octopods. Sites directly involved in oxygen binding or quaternary interactions were highly conserved within the analysed sequence. This study has provided the first insight into molecular and structural mechanisms that have enabled octopods to sustain oxygen supply from polar to tropical conditions. Our findings imply modulation of oxygen binding via charge-charge interaction at the protein surface, which stabilize quaternary interactions among functional units to reduce detrimental effects of high pH on venous oxygen release. Of the observed partial haemocyanin sequence, residue 2545 formed a close link between the FU g surface and the
-
Testing the basic assumption of the hydrogeomorphic approach to assessing wetland functions.
Hruby, T
2001-05-01
The hydrogeomorphic (HGM) approach for developing "rapid" wetland function assessment methods stipulates that the variables used are to be scaled based on data collected at sites judged to be the best at performing the wetland functions (reference standard sites). A critical step in the process is to choose the least altered wetlands in a hydrogeomorphic subclass to use as a reference standard against which other wetlands are compared. The basic assumption made in this approach is that wetlands judged to have had the least human impact have the highest level of sustainable performance for all functions. The levels at which functions are performed in these least altered wetlands are assumed to be "characteristic" for the subclass and "sustainable." Results from data collected in wetlands in the lowlands of western Washington suggest that the assumption may not be appropriate for this region. Teams developing methods for assessing wetland functions did not find that the least altered wetlands in a subclass had a range of performance levels that could be identified as "characteristic" or "sustainable." Forty-four wetlands in four hydrogeomorphic subclasses (two depressional subclasses and two riverine subclasses) were rated by teams of experts on the severity of their human alterations and on the level of performance of 15 wetland functions. An ordinal scale of 1-5 was used to quantify alterations in water regime, soils, vegetation, buffers, and contributing basin. Performance of functions was judged on an ordinal scale of 1-7. Relatively unaltered wetlands were judged to perform individual functions at levels that spanned all of the seven possible ratings in all four subclasses. The basic assumption of the HGM approach, that the least altered wetlands represent "characteristic" and "sustainable" levels of functioning that are different from those found in altered wetlands, was not confirmed. Although the intent of the HGM approach is to use level of functioning as a
-
Inference of Functional Properties from Large-scale Analysis of Enzyme Superfamilies*
Brown, Shoshana D.; Babbitt, Patricia C.
2012-01-01
As increasingly large amounts of data from genome and other sequencing projects become available, new approaches are needed to determine the functions of the proteins these genes encode. We show how large-scale computational analysis can help to address this challenge by linking functional information to sequence and structural similarities using protein similarity networks. Network analyses using three functionally diverse enzyme superfamilies illustrate the use of these approaches for facile updating and comparison of available structures for a large superfamily, for creation of functional hypotheses for metagenomic sequences, and to summarize the limits of our functional knowledge about even well studied superfamilies. PMID:22069325
-
Linked data and user interaction
Cervone, H Frank
2015-01-01
This collection of research papers provides extensive information on deploying services, concepts, and approaches for using open linked data from libraries and other cultural heritage institutions. With a special emphasis on how libraries and other cultural heritage institutions can create effective end user interfaces using open, linked data or other datasets. These papers are essential reading for any one interesting in user interface design or the semantic web.
-
A Fine-Grained API Link Prediction Approach Supporting CMDA Mashup Recommendation
Zhang, J.; Bao, Q.; Lee, T. J.; Ramachandran, R.; Lee, S.; Pan, L.; Gatlin, P. N.; Maskey, M.
2017-12-01
Service (API) discovery and recommendation is key to the wide spread of service oriented architecture and service oriented software engineering. Service recommendation typically relies on service linkage prediction calculated by the semantic distances (or similarities) among services based on their collection of inherent attributes. Given a specific context (mashup goal), however, different attributes may contribute differently to a service linkage. In this work, instead of training a model for all attributes as a whole, a novel approach is presented to simultaneously train separate models for individual attributes. Our contributions are summarized in three-fold. First is that we have developed a scalable attribute-level data model, featuring scalability and extensibility. We have extended Multiplicative Attribute Graph (MAG) model to represent node profiles featuring rich categorical attributes, while relaxing its constraint of requiring a priori knowledge of predefined attributes. LDA is leveraged to dynamically identify attributes based on attribute modeling, and multiple Gaussian fit is applied to find global optimal values. The second contribution is that we have seamlessly integrated the latent relationships between API attributes as well as observed network structure based on historical API usage data. Such a layered information model enables us to predict the probability of a link between two APIs based on their attribute link affinities carrying a variety of information including meta data, semantic data, historical usage data, as well as crowdsourcing user comments and annotations. The third contribution is that we have developed a finegrained context-aware mashup-API recommendation technique. On top of individual models trained for separate attributes, a dedicated layer is trained to represent the latent attribute distribution regarding mashup purpose, i.e., sensitivity of attributes to context. Thus, given the description of an intended mashup, the
-
Dual Approach to the Study of Land Market Functioning
Directory of Open Access Journals (Sweden)
Liliya Oganesovna Oganesyan
2015-12-01
Full Text Available The article reveals the essence, the structural elements and features of the mechanism of functioning of the market of agricultural land. The authors present the supplementing idea on the structural dichotomy of the agricultural land market. In contrast to neoclassical approaches, it is proposed to explore the market based on its structural dichotomy – market property rights and market rights of management. In this context, the mechanism of functioning of agricultural lands market performs the function of a basic element in the system of land relations to ensure market circulation of agricultural land through alienation and assign full or partial rights of land ownership. The use of the institutional approach to the study of market structures justifies the dual nature of the mechanism of functioning of the market of agricultural land due to the fact that on the one hand, the market is slow and limited in the market space of the rare economic good or factor of production, and on the other hand, it is a dynamic institutional and economic system within which the specification of property rights to land is implemented. The structure of the mechanism of functioning and development of agricultural land market is considered as a system of interrelated and interacting elements of state regulation and market self-regulation, based on the principles of coordination and harmonization of personalized economic interests and market law of supply and demand. The combination of elements of market self-regulation and state regulation allows in practice to justify the choice of model combinations of stable and changing elements of the mechanism. This combination complies with the institutional conditions for the functioning of the market of agricultural land considering the dominance of regulated sustainable standards at the market of property rights and in the frames of informal institutions at the market of the management rights. The authors prove the
-
A NON-PARAMETRIC APPROACH TO CONSTRAIN THE TRANSFER FUNCTION IN REVERBERATION MAPPING
Energy Technology Data Exchange (ETDEWEB)
Li, Yan-Rong; Wang, Jian-Min [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049 (China); Bai, Jin-Ming, E-mail: liyanrong@mail.ihep.ac.cn [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)
2016-11-10
Broad emission lines of active galactic nuclei stem from a spatially extended region (broad-line region, BLR) that is composed of discrete clouds and photoionized by the central ionizing continuum. The temporal behaviors of these emission lines are blurred echoes of continuum variations (i.e., reverberation mapping, RM) and directly reflect the structures and kinematic information of BLRs through the so-called transfer function (also known as the velocity-delay map). Based on the previous works of Rybicki and Press and Zu et al., we develop an extended, non-parametric approach to determine the transfer function for RM data, in which the transfer function is expressed as a sum of a family of relatively displaced Gaussian response functions. Therefore, arbitrary shapes of transfer functions associated with complicated BLR geometry can be seamlessly included, enabling us to relax the presumption of a specified transfer function frequently adopted in previous studies and to let it be determined by observation data. We formulate our approach in a previously well-established framework that incorporates the statistical modeling of continuum variations as a damped random walk process and takes into account long-term secular variations which are irrelevant to RM signals. The application to RM data shows the fidelity of our approach.
-
A NON-PARAMETRIC APPROACH TO CONSTRAIN THE TRANSFER FUNCTION IN REVERBERATION MAPPING
International Nuclear Information System (INIS)
Li, Yan-Rong; Wang, Jian-Min; Bai, Jin-Ming
2016-01-01
Broad emission lines of active galactic nuclei stem from a spatially extended region (broad-line region, BLR) that is composed of discrete clouds and photoionized by the central ionizing continuum. The temporal behaviors of these emission lines are blurred echoes of continuum variations (i.e., reverberation mapping, RM) and directly reflect the structures and kinematic information of BLRs through the so-called transfer function (also known as the velocity-delay map). Based on the previous works of Rybicki and Press and Zu et al., we develop an extended, non-parametric approach to determine the transfer function for RM data, in which the transfer function is expressed as a sum of a family of relatively displaced Gaussian response functions. Therefore, arbitrary shapes of transfer functions associated with complicated BLR geometry can be seamlessly included, enabling us to relax the presumption of a specified transfer function frequently adopted in previous studies and to let it be determined by observation data. We formulate our approach in a previously well-established framework that incorporates the statistical modeling of continuum variations as a damped random walk process and takes into account long-term secular variations which are irrelevant to RM signals. The application to RM data shows the fidelity of our approach.
-
Points of convergence between functional and formal approaches to syntactic analysis
DEFF Research Database (Denmark)
Bjerre, Tavs; Engels, Eva; Jørgensen, Henrik
2008-01-01
respectively: The functional approach is represented by Paul Diderichsen's (1936, 1941, 1946, 1964) sætningsskema, ‘sentence model', and the formal approach is represented by analysis whose main features are common to the principles and parameters framework (Chomsky 1986) and the minimalist programme (Chomsky...
-
Mining Functional Modules in Heterogeneous Biological Networks Using Multiplex PageRank Approach.
Li, Jun; Zhao, Patrick X
2016-01-01
Identification of functional modules/sub-networks in large-scale biological networks is one of the important research challenges in current bioinformatics and systems biology. Approaches have been developed to identify functional modules in single-class biological networks; however, methods for systematically and interactively mining multiple classes of heterogeneous biological networks are lacking. In this paper, we present a novel algorithm (called mPageRank) that utilizes the Multiplex PageRank approach to mine functional modules from two classes of biological networks. We demonstrate the capabilities of our approach by successfully mining functional biological modules through integrating expression-based gene-gene association networks and protein-protein interaction networks. We first compared the performance of our method with that of other methods using simulated data. We then applied our method to identify the cell division cycle related functional module and plant signaling defense-related functional module in the model plant Arabidopsis thaliana. Our results demonstrated that the mPageRank method is effective for mining sub-networks in both expression-based gene-gene association networks and protein-protein interaction networks, and has the potential to be adapted for the discovery of functional modules/sub-networks in other heterogeneous biological networks. The mPageRank executable program, source code, the datasets and results of the presented two case studies are publicly and freely available at http://plantgrn.noble.org/MPageRank/.
-
Schad, Megan M.; Szwedo, David E.; Antonishak, Jill; Hare, Amanda; Allen, Joseph P.
2008-01-01
The broader context of relational aggression in adolescent romantic relationships was assessed by considering the ways such aggression emerged from prior experiences of peer pressure and was linked to concurrent difficulties in psychosocial functioning. Longitudinal, multi-reporter data were obtained from 97 adolescents and their best friends at…
-
A probabilistic approach to delineating functional brain regions
DEFF Research Database (Denmark)
Kalbitzer, Jan; Svarer, Claus; Frokjaer, Vibe G
2009-01-01
The purpose of this study was to develop a reliable observer-independent approach to delineating volumes of interest (VOIs) for functional brain regions that are not identifiable on structural MR images. The case is made for the raphe nuclei, a collection of nuclei situated in the brain stem known...... to be densely packed with serotonin transporters (5-hydroxytryptaminic [5-HTT] system). METHODS: A template set for the raphe nuclei, based on their high content of 5-HTT as visualized in parametric (11)C-labeled 3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)-benzonitrile PET images, was created for 10...... healthy subjects. The templates were subsequently included in the region sets used in a previously published automatic MRI-based approach to create an observer- and activity-independent probabilistic VOI map. The probabilistic map approach was tested in a different group of 10 subjects and compared...
-
Directory of Open Access Journals (Sweden)
Paula Ciaurriz
2017-01-01
Full Text Available The enzyme-linked immunosorbent assay (ELISA technique is based on the specific recognition ability of the molecular structure of an antigen (epitope by an antibody and is likely the most important diagnostic technique used today in bioscience. With this methodology, it is possible to diagnose illness, allergies, alimentary fraud, and even to detect small molecules such as toxins, pesticides, heavy metals, etc. For this reason, any procedures that improve the detection limit, sensitivity or reduce the analysis time could have an important impact in several fields. In this respect, many methods have been developed for improving the technique, ranging from fluorescence substrates to methods for increasing the number of enzyme molecules involved in the detection such as the biotin–streptavidin method. In this context, nanotechnology has offered a significant number of proposed solutions, mainly based on the functionalization of nanoparticles from gold to carbon which could be used as antibody carriers as well as reporter enzymes like peroxidase. However, few works have focused on the study of best practices for nanoparticle functionalization for ELISA enhancement. In this work, we use 20 nm gold nanoparticles (AuNPs as a vehicle for secondary antibodies and peroxidase (HRP. The design of experiments technique (DOE and four different methods for biomolecule loading were compared using a rabbit IgG/goat anti-rabbit IgG ELISA model (adsorption, directional, covalent and a combination thereof. As a result, AuNP probes prepared by direct adsorption were the most effective method. AuNPs probes were then used to detect gliadin, one of the main components of wheat gluten, the protein composite that causes celiac disease. With this optimized approach, our data showed a sensitivity increase of at least five times and a lower detection limit with respect to a standard ELISA of at least three times. Additionally, the assay time was remarkably decreased.
-
Radiological emergency response - a functional approach
International Nuclear Information System (INIS)
Chowdhury, P.
1998-01-01
The state of Louisiana's radiological emergency response programme is based on the federal guidance 'Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness in Support of Nuclear Power Plants' (NUREG-0654, FEMA-REP-1 Rev. 1). Over the past 14 years, the planning and implementation of response capabilities became more organized and efficient; the training programme has strengthened considerably; co-ordination with all participating agencies has assumed a more co-operative role, and as a result, a fairly well integrated response planning has evolved. Recently, a more 'functional' approach is being adopted to maximize the programme's efficiency not only for nuclear power plant emergency response, but radiological emergency response as a whole. First, several broad-based 'components' are identified; clusters of 'nodes' are generated for each component; these 'nodes' may be divided into 'sub-nodes' which will contain some 'attributes'; 'relational bonds' among the 'attributes' will exist. When executed, the process begins and continues with the 'nodes' assuming a functional and dynamic role based on the nature and characteristics of the 'attributes'. The typical response based on stand-alone elements is thus eliminated, the overlapping of functions is avoided, and a well structured and efficient organization is produced, that is essential for today's complex nature of emergency response. (author)
-
Age differences in search of web pages: the effects of link size, link number, and clutter.
Grahame, Michael; Laberge, Jason; Scialfa, Charles T
2004-01-01
Reaction time, eye movements, and errors were measured during visual search of Web pages to determine age-related differences in performance as a function of link size, link number, link location, and clutter. Participants (15 young adults, M = 23 years; 14 older adults, M = 57 years) searched Web pages for target links that varied from trial to trial. During one half of the trials, links were enlarged from 10-point to 12-point font. Target location was distributed among the left, center, and bottom portions of the screen. Clutter was manipulated according to the percentage of used space, including graphics and text, and the number of potentially distracting nontarget links was varied. Increased link size improved performance, whereas increased clutter and links hampered search, especially for older adults. Results also showed that links located in the left region of the page were found most easily. Actual or potential applications of this research include Web site design to increase usability, particularly for older adults.
-
The versatile link, a common project for super-LHC
Energy Technology Data Exchange (ETDEWEB)
Amaral, Luis; Dris, Stefanos; Gerardin, Alexandre; Huffman, Todd; Issever, Cigdem; Pacheco, Alberto Jimenez; Jones, Mark; Kwan, Simon; Lee, Shih-Chang; Lian, Zhijun; Liu, Tiankuan; /CERN /Oxford U. /Fermilab /Taipei, Computing Ctr. /Southern Methodist U.
2009-07-01
Radiation tolerant, high speed optoelectronic data transmission links are fundamental building blocks in today's large scale High Energy Physics (HEP) detectors, as exemplified by the four experiments currently under commissioning at the Large Hadron Collider (LHC), see for example. New experiments or upgrades will impose even more stringent demands on these systems from the point of view of performance and radiation tolerance. This can already be seen from the developments underway for the Super Large Hadron Collider (SLHC) project, a proposed upgrade to the LHC aiming at increasing the luminosity of the machine by factor of 10 to 10{sup 35} cm{sup -2}s{sup -1}, and thus providing a better chance to see rare processes and improving statistically marginal measurements. In the past, specific data transmission links have been independently developed by each LHC experiment for data acquisition (DAQ), detector control as well as trigger and timing distribution (TTC). This was justified by the different types of applications being targeted as well as by technological limitations preventing one single solution from fitting all requirements. However with today's maturity of optoelectronic and CMOS technologies it is possible to envisage the development of a general purpose optical link which can cover most transmission applications: a Versatile Link. Such an approach has the clear advantage of concentrating the development effort on one single project targeting an optical link whose final functionality will only result from the topology and configuration settings adopted.
-
Nutritional approach for designing meat-based functional food products with nuts.
Olmedilla-Alonso, B; Granado-Lorencio, F; Herrero-Barbudo, C; Blanco-Navarro, I
2006-01-01
Meat and meat products are essential components of diets in developed countries and despite the convincing evidence that relate them to an increased risk for CVD, a growing consumption of meat products is foreseen. Epidemiological studies show that regular consumption of nuts, in general, and walnuts in particular, correlates inversely with myocardial infarction and ischaemic vascular disease. We assess the nutritional basis for and technological approach to the development of functional meat-based products potentially relevant in cardiovascular disease (CVD) risk reduction. Using the available strategies in the meat industry (reformulation processes) and a food-based approach, we address the design and development of restructured beef steak with added walnuts, potentially functional for CVD risk reduction. Its adequacy as a vehicle for active nutrients is confirmed by a pharmacokinetic pilot study in humans using gamma-tocopherol as an exposure biomarker in chylomicrons during the post-prandial state. Effect and potential "functionality" is being assessed by a dietary intervention study in subjects at risk and markers and indicators related to CVD are being evaluated. Within the conceptual framework of evidence-based medicine, development of meat-based functional products may become a useful approach for specific applications, with a potential market and health benefits of great importance at a population level.
-
Graph-based sequence annotation using a data integration approach.
Pesch, Robert; Lysenko, Artem; Hindle, Matthew; Hassani-Pak, Keywan; Thiele, Ralf; Rawlings, Christopher; Köhler, Jacob; Taubert, Jan
2008-08-25
The automated annotation of data from high throughput sequencing and genomics experiments is a significant challenge for bioinformatics. Most current approaches rely on sequential pipelines of gene finding and gene function prediction methods that annotate a gene with information from different reference data sources. Each function prediction method contributes evidence supporting a functional assignment. Such approaches generally ignore the links between the information in the reference datasets. These links, however, are valuable for assessing the plausibility of a function assignment and can be used to evaluate the confidence in a prediction. We are working towards a novel annotation system that uses the network of information supporting the function assignment to enrich the annotation process for use by expert curators and predicting the function of previously unannotated genes. In this paper we describe our success in the first stages of this development. We present the data integration steps that are needed to create the core database of integrated reference databases (UniProt, PFAM, PDB, GO and the pathway database Ara-Cyc) which has been established in the ONDEX data integration system. We also present a comparison between different methods for integration of GO terms as part of the function assignment pipeline and discuss the consequences of this analysis for improving the accuracy of gene function annotation. The methods and algorithms presented in this publication are an integral part of the ONDEX system which is freely available from http://ondex.sf.net/.
-
Optimisation of the link volume for weakest link failure prediction in NBG-18 nuclear graphite
International Nuclear Information System (INIS)
Hindley, Michael P.; Groenwold, Albert A.; Blaine, Deborah C.; Becker, Thorsten H.
2014-01-01
This paper describes the process for approximating the optimal size of a link volume required for weakest link failure calculation in nuclear graphite, with NBG-18 used as an example. As part of the failure methodology, the link volume is defined in terms of two grouping criteria. The first criterion is a factor of the maximum grain size and the second criterion is a function of an equivalent stress limit. A methodology for approximating these grouping criteria is presented. The failure methodology employs finite element analysis (FEA) in order to predict the failure load, at 50% probability of failure. The average experimental failure load, as determined for 26 test geometries, is used to evaluate the accuracy of the weakest link failure calculations. The influence of the two grouping criteria on the failure load prediction is evaluated by defining an error in prediction across all test cases. Mathematical optimisation is used to find the minimum error across a range of test case failure predictions. This minimum error is shown to deliver the most accurate failure prediction across a whole range of components, although some test cases in the range predict conservative failure load. The mathematical optimisation objective function is penalised to account for non-conservative prediction of the failure load for any test case. The optimisation is repeated and a link volume found for conservative failure prediction. The failure prediction for each test case is evaluated, in detail, for the proposed link volumes. Based on the analysis, link design volumes for NBG-18 are recommended for either accurate or conservative failure prediction
-
``Green's function'' approach & low-mode asymmetries
Masse, Laurent; Clark, Dan; Salmonson, Jay; MacLaren, Steve; Ma, Tammy; Khan, Shahab; Pino, Jesse; Ralph, Jo; Czajka, C.; Tipton, Robert; Landen, Otto; Kyrala, Georges; 2 Team; 1 Team
2017-10-01
Long wavelength, low mode asymmetries are believed to play a leading role in limiting the performance of current ICF implosions on NIF. These long wavelength modes are initiated and driven by asymmetries in the x-ray flux from the hohlraum; however, the underlying hydrodynamics of the implosion also act to amplify these asymmetries. The work presented here aim to deepen our understanding of the interplay of the drive asymmetries and the underlying implosion hydrodynamics in determining the final imploded configuration. This is accomplished through a synthesis of numerical modeling, analytic theory, and experimental data. In detail, we use a Green's function approach to connect the drive asymmetry seen by the capsule to the measured inflight and hot spot symmetries. The approach has been validated against a suite of numerical simulations. Ultimately, we hope this work will identify additional measurements to further constrain the asymmetries and increase hohlraum illumination design flexibility on the NIF. The technique and derivation of associated error bars will be presented. LLC, (LLNS) Contract No. DE-AC52-07NA27344.
-
Spielberg, Jeffrey M; Miller, Gregory A; Engels, Anna S; Herrington, John D; Sutton, Bradley P; Banich, Marie T; Heller, Wendy
2011-01-01
Motivation and executive function are both necessary for the completion of goal-directed behavior. Research investigating the manner in which these processes interact is beginning to emerge and has implicated middle frontal gyrus (MFG) as a site of interaction for relevant neural mechanisms. However, this research has focused on state motivation, and it has not examined functional lateralization. The present study examined the impact of trait levels of approach and avoidance motivation on neural processes associated with executive function. Functional magnetic resonance imaging was conducted while participants performed a color-word Stroop task. Analyses identified brain regions in which trait approach and avoidance motivation (measured by questionnaires) moderated activation associated with executive control. Approach was hypothesized to be associated with left-lateralized MFG activation, whereas avoidance was hypothesized to be associated with right-lateralized MFG activation. Results supported both hypotheses. Present findings implicate areas of middle frontal gyrus in top-down control to guide behavior in accordance with motivational goals. Copyright © 2010 Elsevier Inc. All rights reserved.
-
Cumulant approach to dynamical correlation functions at finite temperatures
International Nuclear Information System (INIS)
Tran Minhtien.
1993-11-01
A new theoretical approach, based on the introduction of cumulants, to calculate thermodynamic averages and dynamical correlation functions at finite temperatures is developed. The method is formulated in Liouville instead of Hilbert space and can be applied to operators which do not require to satisfy fermion or boson commutation relations. The application of the partitioning and projection methods for the dynamical correlation functions is discussed. The present method can be applied to weakly as well as to strongly correlated systems. (author). 9 refs
-
International Nuclear Information System (INIS)
Río, Pablo del; Bleda, Mercedes
2012-01-01
The aim of this paper is to provide a comparative assessment of the innovation effects of instruments which support the diffusion of renewable electricity technologies with a functions-oriented technological innovation system perspective. The paper provides a link between two major streams of the literature: the functions of innovation systems and the literature on renewable electricity support schemes. We show that, when a functional perspective is adopted, feed-in tariffs are likely to be superior to other policy instruments (quotas with tradable green certificates and tendering), although they still need to be complemented with other instruments, most importantly, direct R and D support. Furthermore, those innovation effects are affected by the specific design elements of the instruments chosen. - Highlights: ► A comparison of the innovation effects of instruments for the diffusion of renewable technologies. ► A functions-oriented technological innovation system perspective. ► A link between the functions of innovation systems and the literature on renewable electricity support schemes. ► Feed-in tariffs are likely to be superior to other instruments. ► Innovation effects are affected by the specific design elements of instruments.
-
International Nuclear Information System (INIS)
Ekman, K.B.; Naesman, J.H.
1993-01-01
An ethylene vinyl alcohol copolymer was functionalized with m-isopropenyl-α,α-dimethyl benzyl isocyanate using reactive processing in a mixer. The functionalization introduces pendant unsaturation to the polymer, which allows radiation cross-linked to gel contents >70% at radiation doses below 100 kGy. Unfunctionalized ethylene vinyl alcohol copolymer, on the other hand, forms no gel upon irradiation. The functionalization was completed within a few minutes of reactive mixing, which was confirmed with both FTIR and 13 C-NMR measurements. The oxygen permeability of ethylene vinyl alcohol copolymer increased with increasing degree of functionalization, and irradiation of the samples formed trapped radicals, which act as oxygen scavengers. Consequently no oxygen permeability was detected. However, radical activity was inhibited by annealing the samples at 110 C resulting in a 24% higher oxygen permeability value for the irradiated unfunctionalized copolymer. The oxygen permeability values of the irradiated functionalized samples were approximately 13% lower. Laminates of m-isopropenyl-α,α-dimethyl benzyl isocyanate functionalized ethylene vinyl alcohol copolymer and m-isopropenyl-α,α-dimethyl benzyl isocyanate functionalized ethylene hydroxyethyl methacrylate copolymer acquired improved adhesive strength both at dry and wet conditions as well as at elevated temperature upon exposure to radiation
-
Directory of Open Access Journals (Sweden)
Monika GARG
2012-08-01
Full Text Available In this paper, an integrated approach is proposed for non-recursive formulation of connection coefficients of different orthogonal functions in terms of a generic orthogonal function. The application of these coefficients arises when the product of two orthogonal basis functions are to be expressed in terms of single basis functions. Two significant advantages are achieved; one, the non-recursive formulations avoid memory and stack overflows in computer implementations; two, the integrated approach provides for digital hardware once-designed can be used for different functions. Computational savings achieved with the proposed non-recursive formulation vis-à-vis recursive formulation, reported in the literature so far, have been demonstrated using MATLAB PROFILER.
-
Shin, Won-Kyung; Cho, Jinhyun; Kannan, Aravindaraj G.; Lee, Yoon-Sung; Kim, Dong-Won
2016-01-01
Liquid electrolytes composed of lithium salt in a mixture of organic solvents have been widely used for lithium-ion batteries. However, the high flammability of the organic solvents can lead to thermal runaway and explosions if the system is accidentally subjected to a short circuit or experiences local overheating. In this work, a cross-linked composite gel polymer electrolyte was prepared and applied to lithium-ion polymer cells as a safer and more reliable electrolyte. Mesoporous SiO2 nanoparticles containing reactive methacrylate groups as cross-linking sites were synthesized and dispersed into the fibrous polyacrylonitrile membrane. They directly reacted with gel electrolyte precursors containing tri(ethylene glycol) diacrylate, resulting in the formation of a cross-linked composite gel polymer electrolyte with high ionic conductivity and favorable interfacial characteristics. The mesoporous SiO2 particles also served as HF scavengers to reduce the HF content in the electrolyte at high temperature. As a result, the cycling performance of the lithium-ion polymer cells with cross-linked composite gel polymer electrolytes employing methacrylate-functionalized mesoporous SiO2 nanoparticles was remarkably improved at elevated temperatures. PMID:27189842
-
New approach to equipment quality evaluation method with distinct functions
Directory of Open Access Journals (Sweden)
Milisavljević Vladimir M.
2016-01-01
Full Text Available The paper presents new approach for improving method for quality evaluation and selection of equipment (devices and machinery by applying distinct functions. Quality evaluation and selection of devices and machinery is a multi-criteria problem which involves the consideration of numerous parameters of various origins. Original selection method with distinct functions is based on technical parameters with arbitrary evaluation of each parameter importance (weighting. Improvement of this method, presented in this paper, addresses the issue of weighting of parameters by using Delphi Method. Finally, two case studies are provided, which included quality evaluation of standard boilers for heating and evaluation of load-haul-dump (LHD machines, to demonstrate applicability of this approach. Analytical Hierarchical Process (AHP is used as a control method.
-
Recurrent, Robust and Scalable Patterns Underlie Human Approach and Avoidance
Kennedy, David N.; Lehár, Joseph; Lee, Myung Joo; Blood, Anne J.; Lee, Sang; Perlis, Roy H.; Smoller, Jordan W.; Morris, Robert; Fava, Maurizio
2010-01-01
Background Approach and avoidance behavior provide a means for assessing the rewarding or aversive value of stimuli, and can be quantified by a keypress procedure whereby subjects work to increase (approach), decrease (avoid), or do nothing about time of exposure to a rewarding/aversive stimulus. To investigate whether approach/avoidance behavior might be governed by quantitative principles that meet engineering criteria for lawfulness and that encode known features of reward/aversion function, we evaluated whether keypress responses toward pictures with potential motivational value produced any regular patterns, such as a trade-off between approach and avoidance, or recurrent lawful patterns as observed with prospect theory. Methodology/Principal Findings Three sets of experiments employed this task with beautiful face images, a standardized set of affective photographs, and pictures of food during controlled states of hunger and satiety. An iterative modeling approach to data identified multiple law-like patterns, based on variables grounded in the individual. These patterns were consistent across stimulus types, robust to noise, describable by a simple power law, and scalable between individuals and groups. Patterns included: (i) a preference trade-off counterbalancing approach and avoidance, (ii) a value function linking preference intensity to uncertainty about preference, and (iii) a saturation function linking preference intensity to its standard deviation, thereby setting limits to both. Conclusions/Significance These law-like patterns were compatible with critical features of prospect theory, the matching law, and alliesthesia. Furthermore, they appeared consistent with both mean-variance and expected utility approaches to the assessment of risk. Ordering of responses across categories of stimuli demonstrated three properties thought to be relevant for preference-based choice, suggesting these patterns might be grouped together as a relative preference
-
Incites into Citation Linking using the OAI-PMH
CERN. Geneva
2005-01-01
deposit process. This highly-distributed approach to citation linking utilises the OAI-PMH to transfer structured citation data between IRs and citation indexing services. OpenURL - a standard for contextual linking using bibliographic data - is now a NISO standard. As well as it's linking role, OpenURL is a useful standard for the transfer of bibliographic data for the purposes of...
-
Pascoal, Patrícia M.; Byers, E. Sandra; Alvarez, Maria-João; Santos-Iglesias, Pablo; Nobre, Pedro J.; Pereira, Cicero Roberto; Laan, Ellen
2017-01-01
Researchers have demonstrated that several dimensions of sexual functioning (e.g., sexual desire, arousal, orgasm) are associated with the sexual satisfaction of individuals in a committed mixed-sex (male-female) relationship. We extended this research by comparing a dyadic model that included both
-
Functional approach to a time-dependent self-consistent field theory
International Nuclear Information System (INIS)
Reinhardt, H.
1979-01-01
The time-dependent Hartree-Fock approximation is formulated within the path integral approach. It is shown that by a suitable choice of the collective field the classical equation of motion of the collective field coincides with the time-dependent Hartree (TDH) equation. The consideration is restricted to the TDH equation, since the exchange terms do not appear in the functional approach on the same footing as the direct terms
-
Exact Travelling Solutions of Discrete sine-Gordon Equation via Extended Tanh-Function Approach
International Nuclear Information System (INIS)
Dai Chaoqing; Zhang Jiefang
2006-01-01
In this paper, we generalize the extended tanh-function approach, which was used to find new exact travelling wave solutions of nonlinear partial differential equations or coupled nonlinear partial differential equations, to nonlinear differential-difference equations. As illustration, two series of exact travelling wave solutions of the discrete sine-Gordon equation are obtained by means of the extended tanh-function approach.
-
A real-space stochastic density matrix approach for density functional electronic structure.
Beck, Thomas L
2015-12-21
The recent development of real-space grid methods has led to more efficient, accurate, and adaptable approaches for large-scale electrostatics and density functional electronic structure modeling. With the incorporation of multiscale techniques, linear-scaling real-space solvers are possible for density functional problems if localized orbitals are used to represent the Kohn-Sham energy functional. These methods still suffer from high computational and storage overheads, however, due to extensive matrix operations related to the underlying wave function grid representation. In this paper, an alternative stochastic method is outlined that aims to solve directly for the one-electron density matrix in real space. In order to illustrate aspects of the method, model calculations are performed for simple one-dimensional problems that display some features of the more general problem, such as spatial nodes in the density matrix. This orbital-free approach may prove helpful considering a future involving increasingly parallel computing architectures. Its primary advantage is the near-locality of the random walks, allowing for simultaneous updates of the density matrix in different regions of space partitioned across the processors. In addition, it allows for testing and enforcement of the particle number and idempotency constraints through stabilization of a Feynman-Kac functional integral as opposed to the extensive matrix operations in traditional approaches.
-
Functional Foods and Lifestyle Approaches for Diabetes Prevention and Management
Directory of Open Access Journals (Sweden)
Ahmad Alkhatib
2017-12-01
Full Text Available Functional foods contain biologically active ingredients associated with physiological health benefits for preventing and managing chronic diseases, such as type 2 diabetes mellitus (T2DM. A regular consumption of functional foods may be associated with enhanced anti-oxidant, anti-inflammatory, insulin sensitivity, and anti-cholesterol functions, which are considered integral to prevent and manage T2DM. Components of the Mediterranean diet (MD—such as fruits, vegetables, oily fish, olive oil, and tree nuts—serve as a model for functional foods based on their natural contents of nutraceuticals, including polyphenols, terpenoids, flavonoids, alkaloids, sterols, pigments, and unsaturated fatty acids. Polyphenols within MD and polyphenol-rich herbs—such as coffee, green tea, black tea, and yerba maté—have shown clinically-meaningful benefits on metabolic and microvascular activities, cholesterol and fasting glucose lowering, and anti-inflammation and anti-oxidation in high-risk and T2DM patients. However, combining exercise with functional food consumption can trigger and augment several metabolic and cardiovascular protective benefits, but it is under-investigated in people with T2DM and bariatric surgery patients. Detecting functional food benefits can now rely on an “omics” biological profiling of individuals’ molecular, genetics, transcriptomics, proteomics, and metabolomics, but is under-investigated in multi-component interventions. A personalized approach for preventing and managing T2DM should consider biological and behavioral models, and embed nutrition education as part of lifestyle diabetes prevention studies. Functional foods may provide additional benefits in such an approach.
-
Rouzbehi, Kumars; Miranian, Arash; Candela García, José Ignacio; Luna Alloza, Álvaro; Rodríguez Cortés, Pedro
2014-01-01
In this paper, DC-link voltage control in DC microgrids with photovoltaic (PV) generation and battery, is addressed based on an intelligent approach. The proposed strategy is based on the modeling of the power interface, i.e. power electronic converter, located between the PV array, battery and DC bus, by use of measurement data. For this purpose, a local model network (LMN) is developed to model the converter and then a local linear control (LLC) strategy is designed based on the LMN. Simula...
-
A generalized theory of preferential linking
Hu, Haibo; Guo, Jinli; Liu, Xuan; Wang, Xiaofan
2014-12-01
There are diverse mechanisms driving the evolution of social networks. A key open question dealing with understanding their evolution is: How do various preferential linking mechanisms produce networks with different features? In this paper we first empirically study preferential linking phenomena in an evolving online social network, find and validate the linear preference. We propose an analyzable model which captures the real growth process of the network and reveals the underlying mechanism dominating its evolution. Furthermore based on preferential linking we propose a generalized model reproducing the evolution of online social networks, and present unified analytical results describing network characteristics for 27 preference scenarios. We study the mathematical structure of degree distributions and find that within the framework of preferential linking analytical degree distributions can only be the combinations of finite kinds of functions which are related to rational, logarithmic and inverse tangent functions, and extremely complex network structure will emerge even for very simple sublinear preferential linking. This work not only provides a verifiable origin for the emergence of various network characteristics in social networks, but bridges the micro individuals' behaviors and the global organization of social networks.
-
The Navier-Stokes equations an elementary functional analytic approach
Sohr, Hermann
2001-01-01
The primary objective of this monograph is to develop an elementary and self contained approach to the mathematical theory of a viscous incompressible fluid in a domain 0 of the Euclidean space ]Rn, described by the equations of Navier Stokes. The book is mainly directed to students familiar with basic functional analytic tools in Hilbert and Banach spaces. However, for readers' convenience, in the first two chapters we collect without proof some fundamental properties of Sobolev spaces, distributions, operators, etc. Another important objective is to formulate the theory for a completely general domain O. In particular, the theory applies to arbitrary unbounded, non-smooth domains. For this reason, in the nonlinear case, we have to restrict ourselves to space dimensions n = 2,3 that are also most significant from the physical point of view. For mathematical generality, we will develop the lin earized theory for all n 2 2. Although the functional-analytic approach developed here is, in principle, known ...
-
Directory of Open Access Journals (Sweden)
Ming-Lu Wu
2013-12-01
Full Text Available This paper links professional service firms’ resource-based strategies to their customer-focused performance for formulating service quality improvement priorities. The research applies the structural equation modelling approach to survey data from Hong Kong construction consultants to test some hypotheses. The study validates the various measures of firms’ resource-based strategies and customer-focused performance and bridges the gaps in firms’ organizational learning, core competences and customer-focused performance mediated by their strategic flexibility. The research results have practical implications for professional service firms to deploy resources appropriately to first enhance different competences and then improve customerfocused performance using their different competences.
-
Network worlds : from link analysis to virtual places.
Energy Technology Data Exchange (ETDEWEB)
Joslyn, C. (Cliff)
2002-01-01
Significant progress is being made in knowledge systems through recent advances in the science of very large networks. Attention is now turning in many quarters to the potential impact on counter-terrorism methods. After reviewing some of these advances, we will discuss the difference between such 'network analytic' approaches, which focus on large, homogeneous graph strucures, and what we are calling 'link analytic' approaches, which focus on somewhat smaller graphs with heterogeneous link types. We use this venue to begin the process of rigorously defining link analysis methods, especially the concept of chaining of views of multidimensional databases. We conclude with some speculation on potential connections to virtual world architectures.
-
Cosentino, Stephanie; Devanand, Davangere; Gurland, Barry
2018-01-01
Subjective impairment in memory is a frequently defining feature of subjective cognitive decline (SCD), a state hypothesized to precede objectively apparent cognitive symptoms of Alzheimer's disease (AD) and to hold promise as a non-invasive, inexpensive, preclinical indicator of AD. However, a full model of the factors that contribute to subjective memory (SM), and therefore to SCD, has yet to be articulated. While SM impairment is widely known to be associated with negative affect, the extent to which SM functioning may also reflect other factors, particularly subjective beliefs or perceptions about one's health, is not known. To examine the extent to which SM is associated with subjective perceptions of health more broadly, the current study investigated the link between SM and subjective physical functioning (independent of depressive affect, and objective cognitive and physical function) in an ethnically diverse sample of 471 older adults enrolled in the population-based Northern Manhattan Aging Project. 199 (42%) participants endorsed no difficulty on a 5-point SM index while 272 (58%) endorsed some degree of difficulty. As hypothesized, SM correlated with both depression and subjective physical function, but not with age, education, global cognition, or objective physical function. When objective and subjective physical function were entered in two separate, adjusted linear regressions predicting SM, only subjective physical function and depressive affect independently predicted SM. Subjective perceptions of memory appear to reflect individuals' broader health perceptions in part. Articulating the various correlates of SM will improve identification of SCD specific to preclinical AD.
-
Parton distribution function for quarks in an s-channel approach
Hautmann, F
2007-01-01
We use an s-channel picture of hard hadronic collisions to investigate the parton distribution function for quarks at small momentum fraction x, which corresponds to very high energy scattering. We study the renormalized quark distribution at one loop in this approach. In the high-energy picture, the quark distribution function is expressed in terms of a Wilson-line correlator that represents the cross section for a color dipole to scatter from the proton. We model this Wilson-line correlator in a saturation model. We relate this representation of the quark distribution function to the corresponding representation of the structure function F_T(x,Q^2) for deeply inelastic scattering.
-
Functional renormalization group approach to the two dimensional Bose gas
Energy Technology Data Exchange (ETDEWEB)
Sinner, A; Kopietz, P [Institut fuer Theoretische Physik, Universitaet Frankfurt, Max-von-Laue Strasse 1, 60438 Frankfurt (Germany); Hasselmann, N [International Center for Condensed Matter Physics, Universidade de BrasIlia, Caixa Postal 04667, 70910-900 BrasIlia, DF (Brazil)], E-mail: hasselma@itp.uni-frankfurt.de, E-mail: sinner@itp.uni-frankfurt.de
2009-02-01
We investigate the small frequency and momentum structure of the weakly interacting Bose gas in two dimensions using a functional renormalization group approach. The flow equations are derived within a derivative approximation of the effective action up to second order in spatial and temporal variables and investigated numerically. The truncation we employ is based on the perturbative structure of the theory and is well described as a renormalization group enhanced perturbation theory. It allows to calculate corrections to the Bogoliubov spectrum and to investigate the damping of quasiparticles. Our approach allows to circumvent the divergences which plague the usual perturbative approach.
-
Moral functioning: socio-psychological approach.Social intuitionist theory of John Haidt
Directory of Open Access Journals (Sweden)
Victor A. Zaikin
2017-03-01
Full Text Available The paper studies the methodological aspect of developing social intuitionist approach to moral psychology. The paper reveals the possibility of applying this approach to the study of morality and moral functioning today, emphasizes the representation of issues in moral psychology methodological origins of social psychology, both in Russia and abroad. Social and psychological foundations of social intuitionist approach are described in detail. The research results show that the child perceiving the concept of fairness and variability in the framework of a specific group membership is culturally determined. The matter of special consideration is the theory of the American social psychologist George Haidt. The results of his work and his colleagues’ works are presented herein describing the concept of cultural variable moral intuitions, the findings of empirical studies carried out in the framework of this approach are summarized. The paper reveals the fundamental provisions of the social and intuitionistic theory. The comparative analysis of the social intuitionistic and cognitive approaches in moral psychology is presented. The conclusion that the relativistic understanding of morality is not an obstacle to its study, and the presence of various determinants of moral functioning should be based on further empirical research. The authors conceptualized the current state of social intuitionistic theory of moral functioning, which describes the theoretical and methodological sources of this area (Rawls, 2010; Freud, 2005; Hume, 1996; Hare’s, 1981. As justification for this approach the paper considers the phenomena studied in psychology, social cognition, and those that create the possibility of developing this area, namely affective motivation (Zajonc, 1980, fair-world hypothesis (Lerner, 1965, the objectivity of the illusion (Perkins, Allen, & Hafner , 1983, the phenomenon of «naive realism» (Griffin, & Ross, 1991, group interaction in a
-
Gasulla, I; Capmany, J
2006-10-02
We present a closed-form expression for the evaluation of the transfer function of a multimode fiber (MMF) link based on the electric field propagation model. After validating the result we investigate the potential for broadband transmission in regions far from baseband. We find that MMFs offer the potential for broadband ROF transmission in the microwave and millimetre wave regions in short and middle reach distances.
-
Cretenet, Joel; Dru, Vincent
2009-01-01
Recent research has shown that performing approach versus avoidance behaviors (arm flexion vs. extension) effectively influences cognitive functioning. In another area, lateralized peripheral activations (left vs. right side) of the motivational systems of approach versus avoidance were linked to various performances in cognitive tasks. By…
-
Gerner, Maya; Barak, Sharon; Landa, Jana; Eisenstein, Etzyona
2016-01-01
Functional somatic symptoms (FSS) are a type of somatization phenomenon. Integrative rehabilitation approaches are the preferred treatment for pediatric FSS. Parental roles in the treatment process have not been established. to present 1) a parent-focused treatment (PFT) for pediatric FSS and 2) the approach's preliminary results. The sample included 50 children with physical disabilities due to FSS. All children received PFT including physical and psychological therapy. A detailed description of the program's course and guiding principles is provided. FSS extinction and age-appropriate functioning. Post-program, 84% of participants did not exhibit FSS and 94% returned to age-appropriate functioning. At one-year follow-up, only 5% of participants experienced symptom recurrence. No associations were found between pre-admission symptoms and intervention duration. PFT is beneficial in treating pediatric FSS. Therefore, intensive parental involvement in rehabilitation may be cardinal.
-
Questionnaire of Executive Function for Dancers: An Ecological Approach
Wong, Alina; Rodriguez, Mabel; Quevedo, Liliana; de Cossio, Lourdes Fernandez; Borges, Ariel; Reyes, Alicia; Corral, Roberto; Blanco, Florentino; Alvarez, Miguel
2012-01-01
There is a current debate about the ecological validity of executive function (EF) tests. Consistent with the verisimilitude approach, this research proposes the Ballet Executive Scale (BES), a self-rating questionnaire that assimilates idiosyncratic executive behaviors of classical dance community. The BES was administrated to 149 adolescents,…
-
Multicomponent and Dissipative Self-Assembly Approaches : Towards functional materials
Boekhoven, J.
2012-01-01
The use of self-assembly has proven to be a powerful approach to create smart and functional materials and has led to a vast variety of successful examples. However, the full potential of self-assembly has not been reached. Despite the number of successful artificial materials based on
-
Developmental Programming of Renal Function and Re-Programming Approaches.
Nüsken, Eva; Dötsch, Jörg; Weber, Lutz T; Nüsken, Kai-Dietrich
2018-01-01
Chronic kidney disease affects more than 10% of the population. Programming studies have examined the interrelationship between environmental factors in early life and differences in morbidity and mortality between individuals. A number of important principles has been identified, namely permanent structural modifications of organs and cells, long-lasting adjustments of endocrine regulatory circuits, as well as altered gene transcription. Risk factors include intrauterine deficiencies by disturbed placental function or maternal malnutrition, prematurity, intrauterine and postnatal stress, intrauterine and postnatal overnutrition, as well as dietary dysbalances in postnatal life. This mini-review discusses critical developmental periods and long-term sequelae of renal programming in humans and presents studies examining the underlying mechanisms as well as interventional approaches to "re-program" renal susceptibility toward disease. Clinical manifestations of programmed kidney disease include arterial hypertension, proteinuria, aggravation of inflammatory glomerular disease, and loss of kidney function. Nephron number, regulation of the renin-angiotensin-aldosterone system, renal sodium transport, vasomotor and endothelial function, myogenic response, and tubuloglomerular feedback have been identified as being vulnerable to environmental factors. Oxidative stress levels, metabolic pathways, including insulin, leptin, steroids, and arachidonic acid, DNA methylation, and histone configuration may be significantly altered by adverse environmental conditions. Studies on re-programming interventions focused on dietary or anti-oxidative approaches so far. Further studies that broaden our understanding of renal programming mechanisms are needed to ultimately develop preventive strategies. Targeted re-programming interventions in animal models focusing on known mechanisms will contribute to new concepts which finally will have to be translated to human application. Early
-
Developmental Programming of Renal Function and Re-Programming Approaches
Nüsken, Eva; Dötsch, Jörg; Weber, Lutz T.; Nüsken, Kai-Dietrich
2018-01-01
Chronic kidney disease affects more than 10% of the population. Programming studies have examined the interrelationship between environmental factors in early life and differences in morbidity and mortality between individuals. A number of important principles has been identified, namely permanent structural modifications of organs and cells, long-lasting adjustments of endocrine regulatory circuits, as well as altered gene transcription. Risk factors include intrauterine deficiencies by disturbed placental function or maternal malnutrition, prematurity, intrauterine and postnatal stress, intrauterine and postnatal overnutrition, as well as dietary dysbalances in postnatal life. This mini-review discusses critical developmental periods and long-term sequelae of renal programming in humans and presents studies examining the underlying mechanisms as well as interventional approaches to “re-program” renal susceptibility toward disease. Clinical manifestations of programmed kidney disease include arterial hypertension, proteinuria, aggravation of inflammatory glomerular disease, and loss of kidney function. Nephron number, regulation of the renin–angiotensin–aldosterone system, renal sodium transport, vasomotor and endothelial function, myogenic response, and tubuloglomerular feedback have been identified as being vulnerable to environmental factors. Oxidative stress levels, metabolic pathways, including insulin, leptin, steroids, and arachidonic acid, DNA methylation, and histone configuration may be significantly altered by adverse environmental conditions. Studies on re-programming interventions focused on dietary or anti-oxidative approaches so far. Further studies that broaden our understanding of renal programming mechanisms are needed to ultimately develop preventive strategies. Targeted re-programming interventions in animal models focusing on known mechanisms will contribute to new concepts which finally will have to be translated to human application
-
Directory of Open Access Journals (Sweden)
Henrik Bjørn Nielsen
2007-08-01
Full Text Available The systematic comparison of transcriptional responses of organisms is a powerful tool in functional genomics. For example, mutants may be characterized by comparing their transcript profiles to those obtained in other experiments querying the effects on gene expression of many experimental factors including treatments, mutations and pathogen infections. Similarly, drugs may be discovered by the relationship between the transcript profiles effectuated or impacted by a candidate drug and by the target disease. The integration of such data enables systems biology to predict the interplay between experimental factors affecting a biological system. Unfortunately, direct comparisons of gene expression profiles obtained in independent, publicly available microarray experiments are typically compromised by substantial, experiment-specific biases. Here we suggest a novel yet conceptually simple approach for deriving 'Functional Association(s by Response Overlap' (FARO between microarray gene expression studies. The transcriptional response is defined by the set of differentially expressed genes independent from the magnitude or direction of the change. This approach overcomes the limited comparability between studies that is typical for methods that rely on correlation in gene expression. We apply FARO to a compendium of 242 diverse Arabidopsis microarray experimental factors, including phyto-hormones, stresses and pathogens, growth conditions/stages, tissue types and mutants. We also use FARO to confirm and further delineate the functions of Arabidopsis MAP kinase 4 in disease and stress responses. Furthermore, we find that a large, well-defined set of genes responds in opposing directions to different stress conditions and predict the effects of different stress combinations. This demonstrates the usefulness of our approach for exploiting public microarray data to derive biologically meaningful associations between experimental factors. Finally, our
-
Sayedyahossein, Samar; Rudkouskaya, Alena; Leclerc, Valerie; Dagnino, Lina
2016-02-01
A functional permeability barrier is essential to prevent the passage of water and electrolytes, macromolecules, and pathogens through the epidermis. This is accomplished in terminally differentiated keratinocytes through formation of a cornified envelope and the assembly of tight intercellular junctions. Integrin-linked kinase (ILK) is a scaffold protein essential for hair follicle morphogenesis and epidermal attachment to the basement membrane. However, the biological functions of ILK in differentiated keratinocytes remain poorly understood. Furthermore, whether ILK is implicated in keratinocyte differentiation and intercellular junction formation has remained an unresolved issue. Here we describe a pivotal role for ILK in keratinocyte differentiation responses to increased extracellular Ca(2+), regulation of adherens and tight junction assembly, and the formation of an outside-in permeability barrier toward macromolecules. In the absence of ILK, the calcium sensing receptor, E-cadherin, and ZO-1 fail to translocate to the cell membrane, through mechanisms that involve abnormalities in microtubules and in RhoA activation. In situ, ILK-deficient epidermis exhibits reduced tight junction formation and increased outside-in permeability to a dextran tracer, indicating reduced barrier properties toward macromolecules. Therefore, ILK is an essential component of keratinocyte differentiation programs that contribute to epidermal integrity and the establishment of its barrier properties. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
-
Energy Technology Data Exchange (ETDEWEB)
Shimada, T.; Futakata, A. [Central Research Institute of Electric Power Industry, Tokyo (Japan)
1997-04-01
For a coordinated task to be accomplished in an organization, documents, charts, and data produced by plural workers need to be shared by the plural workers. This information sharing setup will function more effectively when the meanings and purposes of documents, etc., are arranged in good order relative to the other documents and when they are managed as a group of documents organically linked with each other and properly updated as the task approaches completion. In the self-evolving databases proposed so far, five types of document links representing the relations between documents are automatically generated and the documents are unifiedly managed for the documents yielded by coordinated work to be arranged in a proper order. A procedure for automatically generating document links are established on the basis of information received from the document retrieval system and Lotus Notes application. In a self-evolving database, the document on either side of a link is apt to be lost due to users` moving or deleting documents. An automatic procedure is developed in this report which will enable such document links to correctly restore themselves without loss of semantic relations. 12 refs., 11 figs., 3 tabs.
-
Linking Cultural Competence to Functional Life Outcomes in Mental Health Care Settings.
Michalopoulou, Georgia; Falzarano, Pamela; Butkus, Michael; Zeman, Lori; Vershave, Judy; Arfken, Cynthia
2014-01-01
Minorities in the United States have well-documented health disparities. Cultural barriers and biases by health care providers may contribute to lower quality of services which may contribute to these disparities. However, evidence linking cultural competency and health outcomes is lacking. This study, part of an ongoing quality improvement effort, tested the mediation hypothesis that patients' perception of provider cultural competency indirectly influences patients' health outcomes through process of care. Data were from patient satisfaction surveys collected in seven mental health clinics (n=94 minority patients). Consistent with our hypothesis, patients' perception of clinicians' cultural competency was indirectly associated with patients' self-reported improvements in social interactions, improvements in performance at work or school, and improvements in managing life problems through the patients' experience of respect, trust, and communication with the clinician. These findings indicate that process of care characteristics during the clinical encounter influence patients' perceptions of clinicians' cultural competency and affect functional outcomes. © 2013 National Medical Association. Published by Elsevier Inc. All rights reserved.
-
Approach to ''Mind'' using functional neuroimaging
International Nuclear Information System (INIS)
Matsuda, Hiroshi
2006-01-01
This review mainly describes authors' recent investigations concerning neuroimages approaching to even human ''mind'' using techniques of PET, SPECT and functional MRI (fMRI). Progress of such studies greatly owes to the development of image statistics of the brain like statistical parametric mapping (www.fil.ion.ucl.ac.uk/spm/), and brain standards (www.mrc-cbu.cam.ac.uk/Imaging/mnispace.html, and ric.uthscsa.edu/projects/talairach daemon.html). The author discusses and presents images in cases of hallucinations (SPECT and H 2 15 O-PET), autism (SPECT), sleep, depression, and its therapy by transcaranial magnetic stimulation. These studies are expected to contribute to diagnosis and therapy of endogenous neurological disorders. (T.I.)
-
Approach to ''Mind'' using functional neuroimaging
Energy Technology Data Exchange (ETDEWEB)
Matsuda, Hiroshi [Saitama Medical School, Hospital, Moroyama, Saitama (Japan)
2006-05-15
This review mainly describes authors' recent investigations concerning neuroimages approaching to even human ''mind'' using techniques of PET, SPECT and functional MRI (fMRI). Progress of such studies greatly owes to the development of image statistics of the brain like statistical parametric mapping (www.fil.ion.ucl.ac.uk/spm/), and brain standards (www.mrc-cbu.cam.ac.uk/Imaging/mnispace.html, and ric.uthscsa.edu/projects/talairach daemon.html). The author discusses and presents images in cases of hallucinations (SPECT and H{sub 2}{sup 15}O-PET), autism (SPECT), sleep, depression, and its therapy by transcaranial magnetic stimulation. These studies are expected to contribute to diagnosis and therapy of endogenous neurological disorders. (T.I.)
-
International Nuclear Information System (INIS)
Garcia-Aldea, David; Alvarellos, J. E.
2008-01-01
We propose a kinetic energy density functional scheme with nonlocal terms based on the von Weizsaecker functional, instead of the more traditional approach where the nonlocal terms have the structure of the Thomas-Fermi functional. The proposed functionals recover the exact kinetic energy and reproduce the linear response function of homogeneous electron systems. In order to assess their quality, we have tested the total kinetic energies as well as the kinetic energy density for atoms. The results show that these nonlocal functionals give as good results as the most sophisticated functionals in the literature. The proposed scheme for constructing the functionals means a step ahead in the field of fully nonlocal kinetic energy functionals, because they are capable of giving better local behavior than the semilocal functionals, yielding at the same time accurate results for total kinetic energies. Moreover, the functionals enjoy the possibility of being evaluated as a single integral in momentum space if an adequate reference density is defined, and then quasilinear scaling for the computational cost can be achieved
-
Density functional application to strongly correlated electron systems
International Nuclear Information System (INIS)
Eschrig, H.; Koepernik, K.; Chaplygin, I.
2003-01-01
The local spin density approximation plus onsite Coulomb repulsion approach (LSDA+U) to density functional theory is carefully reanalyzed. Its possible link to single-particle Green's function theory is occasionally discussed. A simple and elegant derivation of the important sum rules for the on-site interaction matrix elements linking them to the values of U and J is presented. All necessary expressions for an implementation of LSDA+U into a non-orthogonal basis solver for the Kohn-Sham equations are given, and implementation into the full-potential local-orbital solver (Phys. Rev. B 59 (1999) 1743) is made. Results of application to several planar cuprate structures are reported in detail and conclusions on the interpretation of the physics of the electronic structure of the cuprates are drawn
-
Zeta-function approach to Casimir energy with singular potentials
International Nuclear Information System (INIS)
Khusnutdinov, Nail R.
2006-01-01
In the framework of zeta-function approach the Casimir energy for three simple model system: single delta potential, step function potential and three delta potentials are analyzed. It is shown that the energy contains contributions which are peculiar to the potentials. It is suggested to renormalize the energy using the condition that the energy of infinitely separated potentials is zero which corresponds to subtraction all terms of asymptotic expansion of zeta-function. The energy obtained in this way obeys all physically reasonable conditions. It is finite in the Dirichlet limit, and it may be attractive or repulsive depending on the strength of potential. The effective action is calculated, and it is shown that the surface contribution appears. The renormalization of the effective action is discussed
-
International Nuclear Information System (INIS)
Rozanov, Vladimir V.; Rozanov, Alexei V.
2007-01-01
The paper is devoted to the investigation of the relationship between different methods used to derive weighting functions required to solve numerous inverse problems related to the remote sensing of the Earth's atmosphere by means of scattered solar light observations. The first method commonly referred to as the forward-adjoint approach is based on a joint solution of the forward and adjoint radiative transfer equations and the second one requires the linearized forward radiative transfer equation to be solved. In the framework of the forward-adjoint method we consider two approaches commonly used to derive the weighting functions. These approaches are referenced as the 'response function' and the 'formal solution' techniques, respectively. We demonstrate here that the weighting functions derived employing the formal solution technique can also be obtained substituting the analytical representations for the direct forward and direct adjoint intensities into corresponding expressions obtained in the framework of the response function technique. The advantages and disadvantages of different techniques are discussed
-
Integrative approaches to the prediction of protein functions based on the feature selection
Directory of Open Access Journals (Sweden)
Lee Hyunju
2009-12-01
Full Text Available Abstract Background Protein function prediction has been one of the most important issues in functional genomics. With the current availability of various genomic data sets, many researchers have attempted to develop integration models that combine all available genomic data for protein function prediction. These efforts have resulted in the improvement of prediction quality and the extension of prediction coverage. However, it has also been observed that integrating more data sources does not always increase the prediction quality. Therefore, selecting data sources that highly contribute to the protein function prediction has become an important issue. Results We present systematic feature selection methods that assess the contribution of genome-wide data sets to predict protein functions and then investigate the relationship between genomic data sources and protein functions. In this study, we use ten different genomic data sources in Mus musculus, including: protein-domains, protein-protein interactions, gene expressions, phenotype ontology, phylogenetic profiles and disease data sources to predict protein functions that are labelled with Gene Ontology (GO terms. We then apply two approaches to feature selection: exhaustive search feature selection using a kernel based logistic regression (KLR, and a kernel based L1-norm regularized logistic regression (KL1LR. In the first approach, we exhaustively measure the contribution of each data set for each function based on its prediction quality. In the second approach, we use the estimated coefficients of features as measures of contribution of data sources. Our results show that the proposed methods improve the prediction quality compared to the full integration of all data sources and other filter-based feature selection methods. We also show that contributing data sources can differ depending on the protein function. Furthermore, we observe that highly contributing data sets can be similar among
-
Zuo, Jian; Chung, Neal Tai-Shung
2016-01-01
A novel and effective one-step method has been demonstrated to fabricate cross-linked polyvinylidene fluoride (PVDF) membranes with better mechanical properties and flux for seawater desalination via vacuum membrane distillation (VMD). This method involves the addition of two functional nonsolvent additives; namely, water and ethylenediamine (EDA), into the polymer casting solution. The former acts as a pore forming agent, while the latter performs as a cross-linking inducer. The incorporation of water tends to increase membrane flux via increasing porosity and pore size but sacrifices membrane mechanical properties. Conversely, the presence of EDA enhances membrane mechanical properties through in-situ cross-linking reaction. Therefore, by synergistically combining the effects of both functional additives, the resultant PVDF membranes have shown good MD performance and mechanical properties simultaneously. The parameters that affect the cross-link reaction and membrane mechanical properties such as reaction duration and EDA concentration have been systematically studied. The membranes cast from an optimal reaction condition comprising 0.8 wt % EDA and 3-hour reaction not only shows a 40% enhancement in membrane Young's Modulus compared to the one without EDA but also achieves a good VMD flux of 43.6 L/m2-h at 60°C. This study may open up a totally new approach to design next-generation high performance MD membranes. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4013–4022, 2016
-
Zuo, Jian
2016-05-12
A novel and effective one-step method has been demonstrated to fabricate cross-linked polyvinylidene fluoride (PVDF) membranes with better mechanical properties and flux for seawater desalination via vacuum membrane distillation (VMD). This method involves the addition of two functional nonsolvent additives; namely, water and ethylenediamine (EDA), into the polymer casting solution. The former acts as a pore forming agent, while the latter performs as a cross-linking inducer. The incorporation of water tends to increase membrane flux via increasing porosity and pore size but sacrifices membrane mechanical properties. Conversely, the presence of EDA enhances membrane mechanical properties through in-situ cross-linking reaction. Therefore, by synergistically combining the effects of both functional additives, the resultant PVDF membranes have shown good MD performance and mechanical properties simultaneously. The parameters that affect the cross-link reaction and membrane mechanical properties such as reaction duration and EDA concentration have been systematically studied. The membranes cast from an optimal reaction condition comprising 0.8 wt % EDA and 3-hour reaction not only shows a 40% enhancement in membrane Young\\'s Modulus compared to the one without EDA but also achieves a good VMD flux of 43.6 L/m2-h at 60°C. This study may open up a totally new approach to design next-generation high performance MD membranes. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4013–4022, 2016
-
Ecosystem Functions across Trophic Levels Are Linked to Functional and Phylogenetic Diversity
Thompson, Patrick L.; Davies, T. Jonathan; Gonzalez, Andrew
2015-01-01
In experimental systems, it has been shown that biodiversity indices based on traits or phylogeny can outperform species richness as predictors of plant ecosystem function. However, it is unclear whether this pattern extends to the function of food webs in natural ecosystems. Here we tested whether zooplankton functional and phylogenetic diversity explains the functioning of 23 natural pond communities. We used two measures of ecosystem function: (1) zooplankton community biomass and (2) phytoplankton abundance (Chl a). We tested for diversity-ecosystem function relationships within and across trophic levels. We found a strong correlation between zooplankton diversity and ecosystem function, whereas local environmental conditions were less important. Further, the positive diversity-ecosystem function relationships were more pronounced for measures of functional and phylogenetic diversity than for species richness. Zooplankton and phytoplankton biomass were best predicted by different indices, suggesting that the two functions are dependent upon different aspects of diversity. Zooplankton community biomass was best predicted by zooplankton trait-based functional richness, while phytoplankton abundance was best predicted by zooplankton phylogenetic diversity. Our results suggest that the positive relationship between diversity and ecosystem function can extend across trophic levels in natural environments, and that greater insight into variation in ecosystem function can be gained by combining functional and phylogenetic diversity measures. PMID:25693188
-
Predicting cryptic links in host-parasite networks.
Directory of Open Access Journals (Sweden)
Tad Dallas
2017-05-01
Full Text Available Networks are a way to represent interactions among one (e.g., social networks or more (e.g., plant-pollinator networks classes of nodes. The ability to predict likely, but unobserved, interactions has generated a great deal of interest, and is sometimes referred to as the link prediction problem. However, most studies of link prediction have focused on social networks, and have assumed a completely censused network. In biological networks, it is unlikely that all interactions are censused, and ignoring incomplete detection of interactions may lead to biased or incorrect conclusions. Previous attempts to predict network interactions have relied on known properties of network structure, making the approach sensitive to observation errors. This is an obvious shortcoming, as networks are dynamic, and sometimes not well sampled, leading to incomplete detection of links. Here, we develop an algorithm to predict missing links based on conditional probability estimation and associated, node-level features. We validate this algorithm on simulated data, and then apply it to a desert small mammal host-parasite network. Our approach achieves high accuracy on simulated and observed data, providing a simple method to accurately predict missing links in networks without relying on prior knowledge about network structure.
-
Wightman, Jade; Julio, Flávia; Virués-Ortega, Javier
2014-05-01
Experimental functional analysis is an assessment methodology to identify the environmental factors that maintain problem behavior in individuals with developmental disabilities and in other populations. Functional analysis provides the basis for the development of reinforcement-based approaches to treatment. This article reviews the procedures, validity, and clinical implementation of the methodological variations of functional analysis and function-based interventions. We present six variations of functional analysis methodology in addition to the typical functional analysis: brief functional analysis, single-function tests, latency-based functional analysis, functional analysis of precursors, and trial-based functional analysis. We also present the three general categories of function-based interventions: extinction, antecedent manipulation, and differential reinforcement. Functional analysis methodology is a valid and efficient approach to the assessment of problem behavior and the selection of treatment strategies.
-
Heating tubes of cross-linked polyethylene
International Nuclear Information System (INIS)
Knoeppler, H.; Hoffmann, M.
1981-01-01
Oxygen permeability of plastic tubes for floor heating systems was measured as a function of the reduced oxygen content of water in plastic tubes at a flow rate of 0.5 m/s and a temperature of 30 0 C and as a function of oxygen uptake of low-oxygen water in floor heating tubes. Pipes of VEP, periodically cross-linked polyethylene (Engels process), polypropylene copolymeride, and polybutene were compared. The permeability of periodically cross-linked polyethylene is twice as high as that of VEP. Measurements, results, and consequences for floor heating systems are discussed. (KH) [de
-
Energy Technology Data Exchange (ETDEWEB)
Fuguet, Elisabet [Advanced Measurement and Imaging, Unilever Food and Health Research Institute, Olivier van Noortlaan 120, 3133 AT Vlaardingen (Netherlands)], E-mail: eli.fuguet@gmail.com; Platerink, Chris van [Advanced Measurement and Imaging, Unilever Food and Health Research Institute, Olivier van Noortlaan 120, 3133 AT Vlaardingen (Netherlands); Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands); Janssen, Hans-Gerd [Advanced Measurement and Imaging, Unilever Food and Health Research Institute, Olivier van Noortlaan 120, 3133 AT Vlaardingen (Netherlands); van' t Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam (Netherlands)
2007-11-26
Encapsulates having shells of cross-linked mixtures of proteins and polysaccharides are widely used in the food and pharmaceutical industry for controlled release of actives and flavour compounds. In order to be able to predict the behaviour and the release characteristics of the microcapsules, a better understanding of the nature and extent of the cross-linking reaction is needed. Several analytical techniques were applied for the characterisation of glutardialdehyde (GDA) cross-linked encapsulates made of gelatine and gum arabic. To allow the use of sensitive, high-resolution methods such as chromatography and mass spectrometry, the sample first had to be hydrolysed. In this way, a mixture of amino acids, small peptides and the cross-link moieties was obtained. High-resolution liquid chromatography coupled to high-resolution mass spectrometry (HPLC-MS) was applied to detect possible cross-link markers through a comparison of HPLC-MS mass-chromatograms obtained for cross-linked and non-cross-linked coacervates. HPLC-MS/MS was used to identify the species responsible for the differences. Cross-linking occurred between GDA molecules and lysine and hydroxylysine {epsilon}-amino groups, and up to eight cross-link products of different nature could be identified. They included pyridinium ions and Schiff bases, and also unreacted GDA condensation products. Next, based on the insight gained in the possible chemical structures present in the cross-link markers, methods for selective labelling of these functionalities were employed to allow easier detection of related reaction products. Both liquid chromatography (LC) and gas chromatography (GC) were used in these experiments. Unfortunately, these approaches failed to detect new cross-link markers, most likely as a result of the low levels at which these are present.
-
International Nuclear Information System (INIS)
Fuguet, Elisabet; Platerink, Chris van; Janssen, Hans-Gerd
2007-01-01
Encapsulates having shells of cross-linked mixtures of proteins and polysaccharides are widely used in the food and pharmaceutical industry for controlled release of actives and flavour compounds. In order to be able to predict the behaviour and the release characteristics of the microcapsules, a better understanding of the nature and extent of the cross-linking reaction is needed. Several analytical techniques were applied for the characterisation of glutardialdehyde (GDA) cross-linked encapsulates made of gelatine and gum arabic. To allow the use of sensitive, high-resolution methods such as chromatography and mass spectrometry, the sample first had to be hydrolysed. In this way, a mixture of amino acids, small peptides and the cross-link moieties was obtained. High-resolution liquid chromatography coupled to high-resolution mass spectrometry (HPLC-MS) was applied to detect possible cross-link markers through a comparison of HPLC-MS mass-chromatograms obtained for cross-linked and non-cross-linked coacervates. HPLC-MS/MS was used to identify the species responsible for the differences. Cross-linking occurred between GDA molecules and lysine and hydroxylysine ε-amino groups, and up to eight cross-link products of different nature could be identified. They included pyridinium ions and Schiff bases, and also unreacted GDA condensation products. Next, based on the insight gained in the possible chemical structures present in the cross-link markers, methods for selective labelling of these functionalities were employed to allow easier detection of related reaction products. Both liquid chromatography (LC) and gas chromatography (GC) were used in these experiments. Unfortunately, these approaches failed to detect new cross-link markers, most likely as a result of the low levels at which these are present
-
Defining functional distances over Gene Ontology
Directory of Open Access Journals (Sweden)
del Pozo Angela
2008-01-01
Full Text Available Abstract Background A fundamental problem when trying to define the functional relationships between proteins is the difficulty in quantifying functional similarities, even when well-structured ontologies exist regarding the activity of proteins (i.e. 'gene ontology' -GO-. However, functional metrics can overcome the problems in the comparing and evaluating functional assignments and predictions. As a reference of proximity, previous approaches to compare GO terms considered linkage in terms of ontology weighted by a probability distribution that balances the non-uniform 'richness' of different parts of the Direct Acyclic Graph. Here, we have followed a different approach to quantify functional similarities between GO terms. Results We propose a new method to derive 'functional distances' between GO terms that is based on the simultaneous occurrence of terms in the same set of Interpro entries, instead of relying on the structure of the GO. The coincidence of GO terms reveals natural biological links between the GO functions and defines a distance model Df which fulfils the properties of a Metric Space. The distances obtained in this way can be represented as a hierarchical 'Functional Tree'. Conclusion The method proposed provides a new definition of distance that enables the similarity between GO terms to be quantified. Additionally, the 'Functional Tree' defines groups with biological meaning enhancing its utility for protein function comparison and prediction. Finally, this approach could be for function-based protein searches in databases, and for analysing the gene clusters produced by DNA array experiments.
-
An endothelial link between the benefits of physical exercise in dementia.
Trigiani, Lianne J; Hamel, Edith
2017-08-01
The current absence of a disease-modifying treatment for Alzheimer's disease (AD) and vascular cognitive impairment and dementia (VCID) highlights the necessity for investigating the benefits of non-pharmacological approaches such as physical exercise (PE). Although evidence exists to support an association between regular PE and higher scores on cognitive function tests, and a slower rate of cognitive decline, there is no clear consensus on the underlying molecular mechanisms of the advantages of PE. This review seeks to summarize the positive effects of PE in human and animal studies while highlighting the vascular link between these benefits. Lifestyle factors such as cardiovascular diseases, metabolic syndrome, and sleep apnea will be addressed in relation to the risk they pose in developing AD and VCID, as will molecular factors known to have an impact on either the initiation or the progression of AD and/or VCID. This will include amyloid-beta clearance, oxidative stress, inflammatory responses, neurogenesis, angiogenesis, glucose metabolism, and white matter integrity. Particularly, this review will address how engaging in PE can counter factors that contribute to disease pathogenesis, and how these alterations are linked to endothelial cell function.
-
Developmental Programming of Renal Function and Re-Programming Approaches
Directory of Open Access Journals (Sweden)
Eva Nüsken
2018-02-01
Full Text Available Chronic kidney disease affects more than 10% of the population. Programming studies have examined the interrelationship between environmental factors in early life and differences in morbidity and mortality between individuals. A number of important principles has been identified, namely permanent structural modifications of organs and cells, long-lasting adjustments of endocrine regulatory circuits, as well as altered gene transcription. Risk factors include intrauterine deficiencies by disturbed placental function or maternal malnutrition, prematurity, intrauterine and postnatal stress, intrauterine and postnatal overnutrition, as well as dietary dysbalances in postnatal life. This mini-review discusses critical developmental periods and long-term sequelae of renal programming in humans and presents studies examining the underlying mechanisms as well as interventional approaches to “re-program” renal susceptibility toward disease. Clinical manifestations of programmed kidney disease include arterial hypertension, proteinuria, aggravation of inflammatory glomerular disease, and loss of kidney function. Nephron number, regulation of the renin–angiotensin–aldosterone system, renal sodium transport, vasomotor and endothelial function, myogenic response, and tubuloglomerular feedback have been identified as being vulnerable to environmental factors. Oxidative stress levels, metabolic pathways, including insulin, leptin, steroids, and arachidonic acid, DNA methylation, and histone configuration may be significantly altered by adverse environmental conditions. Studies on re-programming interventions focused on dietary or anti-oxidative approaches so far. Further studies that broaden our understanding of renal programming mechanisms are needed to ultimately develop preventive strategies. Targeted re-programming interventions in animal models focusing on known mechanisms will contribute to new concepts which finally will have to be translated
-
Predicting the Retention Behavior of Specific O-Linked Glycopeptides.
Badgett, Majors J; Boyes, Barry; Orlando, Ron
2017-09-01
O -Linked glycosylation is a common post-translational modification that can alter the overall structure, polarity, and function of proteins. Reverse-phase (RP) chromatography is the most common chromatographic approach to analyze O -glycosylated peptides and their unmodified counterparts, even though this approach often does not provide adequate separation of these two species. Hydrophilic interaction liquid chromatography (HILIC) can be a solution to this problem, as the polar glycan interacts with the polar stationary phase and potentially offers the ability to resolve the peptide from its modified form(s). In this paper, HILIC is used to separate peptides with O - N -acetylgalactosamine ( O -GalNAc), O - N -acetylglucosamine ( O -GlcNAc), and O -fucose additions from their native forms, and coefficients representing the extent of hydrophilicity were derived using linear regression analysis as a means to predict the retention times of peptides with these modifications.
-
Swartz, Andrew R; Sun, Qing; Chen, Wilfred
2017-05-08
Affinity precipitation is an ideal alternative to chromatography for antibody purification because it combines the high selectivity of an affinity ligand with the operational benefits of precipitation. However, the widespread use of elastin-like polypeptide (ELP) capture scaffolds for antibody purification has been hindered by the high salt concentrations and temperatures necessary for efficient ELP aggregation. In this paper, we employed a tandem approach to enhance ELP aggregation by enlarging the dimension of the capturing scaffold and by creating IgG-triggered scaffold cross-linking. This was accomplished by covalently conjugating the Z-domain-ELP (Z-ELP) capturing scaffold to a 25 nm diameter E2 protein nanocage using Sortase A ligation. We demonstrated the isothermal recovery of IgG in the virtual absence of salt due to the significantly increased scaffold dimension and cross-linking from multivalent IgG-E2 interactions. Because IgG cross-linking is reversible at low pH, it may be feasible to achieve a high yielding IgG purification by isothermal phase separation using a simple pH trigger.
-
Moin, Mazahar; Bakshi, Achala; Saha, Anusree; Dutta, Mouboni; Kirti, P B
2017-07-01
The epitome of any genome research is to identify all the existing genes in a genome and investigate their roles. Various techniques have been applied to unveil the functions either by silencing or over-expressing the genes by targeted expression or random mutagenesis. Rice is the most appropriate model crop for generating a mutant resource for functional genomic studies because of the availability of high-quality genome sequence and relatively smaller genome size. Rice has syntenic relationships with members of other cereals. Hence, characterization of functionally unknown genes in rice will possibly provide key genetic insights and can lead to comparative genomics involving other cereals. The current review attempts to discuss the available gain-of-function mutagenesis techniques for functional genomics, emphasizing the contemporary approach, activation tagging and alterations to this method for the enhancement of yield and productivity of rice. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.
-
Propagation engineering in radio links design
Ghasemi, Abdollah; Ghasemi, Farshid
2013-01-01
Propagation Engineering in Radio Link Design covers the basic principles of radiowaves propagation in a practical manner. This fundamental understanding enables the readers to design radio links efficiently. This book elaborates on new achievements as well as recently developed propagation models. This is in addition to a comprehensive overview of fundamentals of propagation in various scenarios. It examines theoretical calculations, approaches and applied procedures needed for radio links design. The authors study and analysis of the main propagation phenomena and its mechanisms based on the recommendations of International Telecommunications Union, (ITU). The book has been organized in 9 chapters and examines the role of antennas and passive reflectors in radio services, propagation mechanisms related to radar, satellite, short distance, broadcasting and trans-horizon radio links, with two chapters devoted to radio noise and main parameters of radio link design. The book presents some 278 illustration...
-
Linked Data Paves the Way to Improved Health Care
Directory of Open Access Journals (Sweden)
Michael Gaucher
2017-04-01
This presentation demonstrates how new knowledge created using linked data can inform decision and policy makers, and lead to action within the health system. Several examples are presented to illustrate the approach and types of data being linked.
-
Executing SPARQL Queries over the Web of Linked Data
Hartig, Olaf; Bizer, Christian; Freytag, Johann-Christoph
The Web of Linked Data forms a single, globally distributed dataspace. Due to the openness of this dataspace, it is not possible to know in advance all data sources that might be relevant for query answering. This openness poses a new challenge that is not addressed by traditional research on federated query processing. In this paper we present an approach to execute SPARQL queries over the Web of Linked Data. The main idea of our approach is to discover data that might be relevant for answering a query during the query execution itself. This discovery is driven by following RDF links between data sources based on URIs in the query and in partial results. The URIs are resolved over the HTTP protocol into RDF data which is continuously added to the queried dataset. This paper describes concepts and algorithms to implement our approach using an iterator-based pipeline. We introduce a formalization of the pipelining approach and show that classical iterators may cause blocking due to the latency of HTTP requests. To avoid blocking, we propose an extension of the iterator paradigm. The evaluation of our approach shows its strengths as well as the still existing challenges.
-
Semantic analysis of links in the musical Wikipedia
DEFF Research Database (Denmark)
Mølgaard, Lasse Lohilahti; Hansen, Lars Kai; Larsen, Jan
2008-01-01
are generated automatically, and they may even maliciously be used to promote certain topics. Wikipedia has been analyzed recently using methods fromWeb and text mining, however, the fact the link structure is different from the Web’s makes this approach questionable. To better understand the link structure...
-
Gagic, Vesna; Bartomeus, Ignasi; Jonsson, Tomas; Taylor, Astrid; Winqvist, Camilla; Fischer, Christina; Slade, Eleanor M; Steffan-Dewenter, Ingolf; Emmerson, Mark; Potts, Simon G; Tscharntke, Teja; Weisser, Wolfgang; Bommarco, Riccardo
2015-02-22
Drastic biodiversity declines have raised concerns about the deterioration of ecosystem functions and have motivated much recent research on the relationship between species diversity and ecosystem functioning. A functional trait framework has been proposed to improve the mechanistic understanding of this relationship, but this has rarely been tested for organisms other than plants. We analysed eight datasets, including five animal groups, to examine how well a trait-based approach, compared with a more traditional taxonomic approach, predicts seven ecosystem functions below- and above-ground. Trait-based indices consistently provided greater explanatory power than species richness or abundance. The frequency distributions of single or multiple traits in the community were the best predictors of ecosystem functioning. This implies that the ecosystem functions we investigated were underpinned by the combination of trait identities (i.e. single-trait indices) and trait complementarity (i.e. multi-trait indices) in the communities. Our study provides new insights into the general mechanisms that link biodiversity to ecosystem functioning in natural animal communities and suggests that the observed responses were due to the identity and dominance patterns of the trait composition rather than the number or abundance of species per se. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
-
Thomas, Holly N; Thurston, Rebecca C
2016-05-01
A satisfying sex life is an important component of overall well-being, but sexual dysfunction is common, especially in midlife women. The aim of this review is (a) to define sexual function and dysfunction, (b) to present theoretical models of female sexual response, (c) to examine longitudinal studies of how sexual function changes during midlife, and (d) to review treatment options. Four types of female sexual dysfunction are currently recognized: Female Orgasmic Disorder, Female Sexual Interest/Arousal Disorder, Genito-Pelvic Pain/Penetration Disorder, and Substance/Medication-Induced Sexual Dysfunction. However, optimal sexual function transcends the simple absence of dysfunction. A biopsychosocial approach that simultaneously considers physical, psychological, sociocultural, and interpersonal factors is necessary to guide research and clinical care regarding women's sexual function. Most longitudinal studies reveal an association between advancing menopause status and worsening sexual function. Psychosocial variables, such as availability of a partner, relationship quality, and psychological functioning, also play an integral role. Future directions for research should include deepening our understanding of how sexual function changes with aging and developing safe and effective approaches to optimizing women's sexual function with aging. Overall, holistic, biopsychosocial approaches to women's sexual function are necessary to fully understand and treat this key component of midlife women's well-being. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
-
An exploratory data analysis of electroencephalograms using the functional boxplots approach
Ngo, Duy
2015-08-19
Many model-based methods have been developed over the last several decades for analysis of electroencephalograms (EEGs) in order to understand electrical neural data. In this work, we propose to use the functional boxplot (FBP) to analyze log periodograms of EEG time series data in the spectral domain. The functional bloxplot approach produces a median curve—which is not equivalent to connecting medians obtained from frequency-specific boxplots. In addition, this approach identifies a functional median, summarizes variability, and detects potential outliers. By extending FBPs analysis from one-dimensional curves to surfaces, surface boxplots are also used to explore the variation of the spectral power for the alpha (8–12 Hz) and beta (16–32 Hz) frequency bands across the brain cortical surface. By using rank-based nonparametric tests, we also investigate the stationarity of EEG traces across an exam acquired during resting-state by comparing the spectrum during the early vs. late phases of a single resting-state EEG exam.
-
An exploratory data analysis of electroencephalograms using the functional boxplots approach
Ngo, Duy; Sun, Ying; Genton, Marc G.; Wu, Jennifer; Srinivasan, Ramesh; Cramer, Steven C.; Ombao, Hernando
2015-01-01
Many model-based methods have been developed over the last several decades for analysis of electroencephalograms (EEGs) in order to understand electrical neural data. In this work, we propose to use the functional boxplot (FBP) to analyze log periodograms of EEG time series data in the spectral domain. The functional bloxplot approach produces a median curve—which is not equivalent to connecting medians obtained from frequency-specific boxplots. In addition, this approach identifies a functional median, summarizes variability, and detects potential outliers. By extending FBPs analysis from one-dimensional curves to surfaces, surface boxplots are also used to explore the variation of the spectral power for the alpha (8–12 Hz) and beta (16–32 Hz) frequency bands across the brain cortical surface. By using rank-based nonparametric tests, we also investigate the stationarity of EEG traces across an exam acquired during resting-state by comparing the spectrum during the early vs. late phases of a single resting-state EEG exam. PMID:26347598
-
An exploratory data analysis of electroencephalograms using the functional boxplots approach
Ngo, Duy; Sun, Ying; Genton, Marc G.; Wu, Jennifer; Srinivasan, Ramesh; Cramer, Steven C.; Ombao, Hernando
2015-01-01
Many model-based methods have been developed over the last several decades for analysis of electroencephalograms (EEGs) in order to understand electrical neural data. In this work, we propose to use the functional boxplot (FBP) to analyze log periodograms of EEG time series data in the spectral domain. The functional bloxplot approach produces a median curve—which is not equivalent to connecting medians obtained from frequency-specific boxplots. In addition, this approach identifies a functional median, summarizes variability, and detects potential outliers. By extending FBPs analysis from one-dimensional curves to surfaces, surface boxplots are also used to explore the variation of the spectral power for the alpha (8–12 Hz) and beta (16–32 Hz) frequency bands across the brain cortical surface. By using rank-based nonparametric tests, we also investigate the stationarity of EEG traces across an exam acquired during resting-state by comparing the spectrum during the early vs. late phases of a single resting-state EEG exam.
-
Links between plant litter chemistry, species diversity, and below-ground ecosystem function.
Meier, Courtney L; Bowman, William D
2008-12-16
Decomposition is a critical source of plant nutrients, and drives the largest flux of terrestrial C to the atmosphere. Decomposing soil organic matter typically contains litter from multiple plant species, yet we lack a mechanistic understanding of how species diversity influences decomposition processes. Here, we show that soil C and N cycling during decomposition are controlled by the composition and diversity of chemical compounds within plant litter mixtures, rather than by simple metrics of plant species diversity. We amended native soils with litter mixtures containing up to 4 alpine plant species, and we used 9 litter chemical traits to evaluate the chemical composition (i.e., the identity and quantity of compounds) and chemical diversity of the litter mixtures. The chemical composition of the litter mixtures was the strongest predictor of soil respiration, net N mineralization, and microbial biomass N. Soil respiration and net N mineralization rates were also significantly correlated with the chemical diversity of the litter mixtures. In contrast, soil C and N cycling rates were poorly correlated with plant species richness, and there was no relationship between species richness and the chemical diversity of the litter mixtures. These results indicate that the composition and diversity of chemical compounds in litter are potentially important functional traits affecting decomposition, and simple metrics like plant species richness may fail to capture variation in these traits. Litter chemical traits therefore provide a mechanistic link between organisms, species diversity, and key components of below-ground ecosystem function.
-
Bertani, Ilaria; Rusconi, Laura; Bolognese, Fabrizio; Forlani, Greta; Conca, Barbara; De Monte, Lucia; Badaracco, Gianfranco; Landsberger, Nicoletta; Kilstrup-Nielsen, Charlotte
2006-10-20
Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in patients with Rett syndrome, West syndrome, and X-linked infantile spasms sharing the common features of generally intractable early seizures and mental retardation. Disease-causing mutations are distributed in both the catalytic domain and in the large COOH terminus. In this report, we examine the functional consequences of some Rett mutations of CDKL5 together with some synthetically designed derivatives useful to underline the functional domains of the protein. The mutated CDKL5 derivatives have been subjected to in vitro kinase assays and analyzed for phosphorylation of the TEY (Thr-Glu-Tyr) motif within the activation loop, their subcellular localization, and the capacity of CDKL5 to interact with itself. Whereas wild-type CDKL5 autophosphorylates and mediates the phosphorylation of the methyl-CpG-binding protein 2 (MeCP2) in vitro, Rett-mutated proteins show both impaired and increased catalytic activity suggesting that a tight regulation of CDKL5 is required for correct brain functions. Furthermore, we show that CDKL5 can self-associate and mediate the phosphorylation of its own TEY (Thr-Glu-Tyr) motif. Eventually, we show that the COOH terminus regulates CDKL5 properties; in particular, it negatively influences the catalytic activity and is required for its proper sub-nuclear localization. We propose a model in which CDKL5 phosphorylation is required for its entrance into the nucleus whereas a portion of the COOH-terminal domain is responsible for a stable residency in this cellular compartment probably through protein-protein interactions.
-
Applying linked data approaches to pharmacology: Architectural decisions and implementation
Gray, A.J.G; Groth, P.T.; Loizou, A.; Askjaer, S; Brenninkmeijer, C; Burger, K.; Chichester, C.; Evelo, C.T.; Goble, C.A.; Harland, L; Pettifier, S; Thompson, M.; Waagmeester, A; William, A.J
2014-01-01
The discovery of new medicines requires pharmacologists to interact with a number of information sources ranging from tabular data to scientific papers, and other specialized formats. In this application report, we describe a linked data platform for integrating multiple pharmacology datasets that
-
DEFF Research Database (Denmark)
van der Kooij, Michael A; Fantin, Martina; Kraev, Igor
2014-01-01
and are related to similar abnormalities in animal models. Chronic stress increases the likelihood for affective disorders and has been shown to induce changes in neural structure and function in different brain regions, with the hippocampus being highly vulnerable to stress. Previous studies have shown evidence......Neuroligins (NLGNs) are cell adhesion molecules that are important for proper synaptic formation and functioning and are critical regulators of the balance between neural excitation/inhibition (E/I). Mutations in NLGNs have been linked to psychiatric disorders in humans involving social dysfunction...
-
A discrimlnant function approach to ecological site classification in northern New England
James M. Fincher; Marie-Louise Smith
1994-01-01
Describes one approach to ecologically based classification of upland forest community types of the White and Green Mountain physiographic regions. The classification approach is based on an intensive statistical analysis of the relationship between the communities and soil-site factors. Discriminant functions useful in distinguishing between types based on soil-site...
-
Molecular Model for HNBR with Tunable Cross-Link Density.
Molinari, N; Khawaja, M; Sutton, A P; Mostofi, A A
2016-12-15
We introduce a chemically inspired, all-atom model of hydrogenated nitrile butadiene rubber (HNBR) and assess its performance by computing the mass density and glass-transition temperature as a function of cross-link density in the structure. Our HNBR structures are created by a procedure that mimics the real process used to produce HNBR, that is, saturation of the carbon-carbon double bonds in NBR, either by hydrogenation or by cross-linking. The atomic interactions are described by the all-atom "Optimized Potentials for Liquid Simulations" (OPLS-AA). In this paper, first, we assess the use of OPLS-AA in our models, especially using NBR bulk properties, and second, we evaluate the validity of the proposed model for HNBR by investigating mass density and glass transition as a function of the tunable cross-link density. Experimental densities are reproduced within 3% for both elastomers, and qualitatively correct trends in the glass-transition temperature as a function of monomer composition and cross-link density are obtained.
-
Narsai, Reena; Devenish, James; Castleden, Ian; Narsai, Kabir; Xu, Lin; Shou, Huixia; Whelan, James
2013-12-01
Omics research in Oryza sativa (rice) relies on the use of multiple databases to obtain different types of information to define gene function. We present Rice DB, an Oryza information portal that is a functional genomics database, linking gene loci to comprehensive annotations, expression data and the subcellular location of encoded proteins. Rice DB has been designed to integrate the direct comparison of rice with Arabidopsis (Arabidopsis thaliana), based on orthology or 'expressology', thus using and combining available information from two pre-eminent plant models. To establish Rice DB, gene identifiers (more than 40 types) and annotations from a variety of sources were compiled, functional information based on large-scale and individual studies was manually collated, hundreds of microarrays were analysed to generate expression annotations, and the occurrences of potential functional regulatory motifs in promoter regions were calculated. A range of computational subcellular localization predictions were also run for all putative proteins encoded in the rice genome, and experimentally confirmed protein localizations have been collated, curated and linked to functional studies in rice. A single search box allows anything from gene identifiers (for rice and/or Arabidopsis), motif sequences, subcellular location, to keyword searches to be entered, with the capability of Boolean searches (such as AND/OR). To demonstrate the utility of Rice DB, several examples are presented including a rice mitochondrial proteome, which draws on a variety of sources for subcellular location data within Rice DB. Comparisons of subcellular location, functional annotations, as well as transcript expression in parallel with Arabidopsis reveals examples of conservation between rice and Arabidopsis, using Rice DB (http://ricedb.plantenergy.uwa.edu.au). © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.
-
Directory of Open Access Journals (Sweden)
Vasieva O
2011-09-01
Full Text Available Olga VasievaInstitute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom; Fellowship for the Interpretation of Genomes, Burr Ridge, IL, USAAbstract: Shwachman-Bodian-Diamond syndrome (SBDS is linked to a mutation in a single gene. The SBDS proinvolved in RNA metabolism and ribosome-associated functions, but SBDS mutation is primarily linked to a defect in polymorphonuclear leukocytes unable to orient correctly in a spatial gradient of chemoattractants. Results of data mining and comparative genomic approaches undertaken in this study suggest that SBDS protein is also linked to tRNA metabolism and translation initiation. Analysis of crosstalk between translation machinery and cytoskeletal dynamics provides new insights into the cellular chemotactic defects caused by SBDS protein malfunction. The proposed functional interactions provide a new approach to exploit potential targets in the treatment and monitoring of this disease.Keywords: Shwachman-Bodian-Diamond syndrome, wybutosine, tRNA, chemotaxis, translation, genomics, gene proximity
-
Fluidic Logic Used in a Systems Approach to Enable Integrated Single-cell Functional Analysis
Directory of Open Access Journals (Sweden)
Naveen Ramalingam
2016-09-01
Full Text Available The study of single cells has evolved over the past several years to include expression and genomic analysis of an increasing number of single cells. Several studies have demonstrated wide-spread variation and heterogeneity within cell populations of similar phenotype. While the characterization of these populations will likely set the foundation for our understanding of genomic- and expression-based diversity, it will not be able to link the functional differences of a single cell to its underlying genomic structure and activity. Currently, it is difficult to perturb single cells in a controlled environment, monitor and measure the response due to perturbation, and link these response measurements to downstream genomic and transcriptomic analysis. In order to address this challenge, we developed a platform to integrate and miniaturize many of the experimental steps required to study single-cell function. The heart of this platform is an elastomer-based Integrated Fluidic Circuit (IFC that uses fluidic logic to select and sequester specific single cells based on a phenotypic trait for downstream experimentation. Experiments with sequestered cells that have been performed include on-chip culture, exposure to a variety of stimulants, and post-exposure image-based response analysis, followed by preparation of the mRNA transcriptome for massively parallel sequencing analysis. The flexible system embodies experimental design and execution that enable routine functional studies of single cells.
-
Kurukuri, Srihari; Worswick, Michael J.
2013-12-01
An alternative approach is proposed to utilize symmetric yield functions for modeling the tension-compression asymmetry commonly observed in hcp materials. In this work, the strength differential (SD) effect is modeled by choosing separate symmetric plane stress yield functions (for example, Barlat Yld 2000-2d) for the tension i.e., in the first quadrant of principal stress space, and compression i.e., third quadrant of principal stress space. In the second and fourth quadrants, the yield locus is constructed by adopting interpolating functions between uniaxial tensile and compressive stress states. In this work, different interpolating functions are chosen and the predictive capability of each approach is discussed. The main advantage of this proposed approach is that the yield locus parameters are deterministic and relatively easy to identify when compared to the Cazacu family of yield functions commonly used for modeling SD effect observed in hcp materials.
-
From Equation to Inequality Using a Function-Based Approach
Verikios, Petros; Farmaki, Vassiliki
2010-01-01
This article presents features of a qualitative research study concerning the teaching and learning of school algebra using a function-based approach in a grade 8 class, of 23 students, in 26 lessons, in a state school of Athens, in the school year 2003-2004. In this article, we are interested in the inequality concept and our aim is to…
-
Hall, E.K.; Maixner, F.; Franklin, O.; Daims, H.; Richter, A.; Battin, T.
2011-01-01
Currently, one of the biggest challenges in microbial and ecosystem ecology is to develop conceptual models that organize the growing body of information on environmental microbiology into a clear mechanistic framework with a direct link to ecosystem processes. Doing so will enable development of testable hypotheses to better direct future research and increase understanding of key constraints on biogeochemical networks. Although the understanding of phenotypic and genotypic diversity of microorganisms in the environment is rapidly accumulating, how controls on microbial physiology ultimately affect biogeochemical fluxes remains poorly understood. We propose that insight into constraints on biogeochemical cycles can be achieved by a more rigorous evaluation of microbial community biomass composition within the context of ecological stoichiometry. Multiple recent studies have pointed to microbial biomass stoichiometry as an important determinant of when microorganisms retain or recycle mineral nutrients. We identify the relevant cellular components that most likely drive changes in microbial biomass stoichiometry by defining a conceptual model rooted in ecological stoichiometry. More importantly, we show how X-ray microanalysis (XRMA), nanoscale secondary ion mass spectroscopy (NanoSIMS), Raman microspectroscopy, and in situ hybridization techniques (for example, FISH) can be applied in concert to allow for direct empirical evaluation of the proposed conceptual framework. This approach links an important piece of the ecological literature, ecological stoichiometry, with the molecular front of the microbial revolution, in an attempt to provide new insight into how microbial physiology could constrain ecosystem processes.
-
Auxiliary functions of the LISA laser link: ranging, clock noise transfer and data communication
International Nuclear Information System (INIS)
Heinzel, Gerhard; Esteban, Juan Jose; Barke, Simon; Otto, Markus; Wang Yan; Garcia, Antonio F; Danzmann, Karsten
2011-01-01
The Laser Interferometer Space Antenna (LISA) is required to reduce two important noise sources by post-processing on the ground using time-delay interferometry (TDI): phase noise of the on-board reference clocks and laser frequency noise. To achieve the desired suppression, the TDI algorithm needs measurements of the differential clock noise between any two spacecraft and inter-spacecraft ranging measurements with at least 1 m accuracy, which is beyond the precision of ground-based measurements for deep space missions. Therefore, we need on-board measurements by transmitting clock noise and ranging information between the spacecraft as auxiliary functions of the laser link. This paper reports our current experimental results in clock noise transfer and ranging for noise subtraction via post-processing as well as additional data transfer.
-
The 'wet mind': water and functional neuroimaging
International Nuclear Information System (INIS)
Le Bihan, Denis
2007-01-01
Functional neuroimaging has emerged as an important approach to study the brain and the mind. Surprisingly, although they are based on radically different physical approaches both positron emission tomography (PET) and magnetic resonance imaging (MRI) make brain activation imaging possible through measurements involving water molecules. So far, PET and MRI functional imaging have relied on the principle that neuronal activation and blood flow are coupled through metabolism. However, a new paradigm has emerged to look at brain activity through the observation with MRI of the molecular diffusion of water. In contrast with the former approaches diffusion MRI has the potential to reveal changes in the intrinsic water physical properties during brain activation, which could be more intimately linked to the neuronal activation mechanisms and lead to an improved spatial and temporal resolution. However, this link has yet to be fully confirmed and understood. To shed light on the possible relationship between water and brain activation, this introductory paper reviews the most recent data on the physical properties of water and on the status of water in biological tissues, and evaluates their relevance to brain diffusion MRI. The biophysical mechanisms of brain activation are then reassessed to reveal their intimacy with the physical properties of water, which may come to be regarded as the 'molecule of the mind'. (invited topical review)
-
Abelian Chern endash Simons theory. II. A functional integral approach
International Nuclear Information System (INIS)
Manoliu, M.
1998-01-01
Following Witten, [Commun. Math. Phys. 21, 351 endash 399 (1989)] we approach the Abelian quantum Chern endash Simons (CS) gauge theory from a Feynman functional integral point of view. We show that for 3-manifolds with and without a boundary the formal functional integral definitions lead to mathematically proper expressions that agree with the results from the rigorous construction [J. Math. Phys. 39, 170 endash 206 (1998)] of the Abelian CS topological quantum field theory via geometric quantization. copyright 1998 American Institute of Physics
-
Optical links in handheld multimedia devices
van Geffen, S.; Duis, J.; Miller, R.
2008-04-01
Ever emerging applications in handheld multimedia devices such as mobile phones, laptop computers, portable video games and digital cameras requiring increased screen resolutions are driving higher aggregate bitrates between host processor and display(s) enabling services such as mobile video conferencing, video on demand and TV broadcasting. Larger displays and smaller phones require complex mechanical 3D hinge configurations striving to combine maximum functionality with compact building volumes. Conventional galvanic interconnections such as Micro-Coax and FPC carrying parallel digital data between host processor and display module may produce Electromagnetic Interference (EMI) and bandwidth limitations caused by small cable size and tight cable bends. To reduce the number of signals through a hinge, the mobile phone industry, organized in the MIPI (Mobile Industry Processor Interface) alliance, is currently defining an electrical interface transmitting serialized digital data at speeds >1Gbps. This interface allows for electrical or optical interconnects. Above 1Gbps optical links may offer a cost effective alternative because of their flexibility, increased bandwidth and immunity to EMI. This paper describes the development of optical links for handheld communication devices. A cable assembly based on a special Plastic Optical Fiber (POF) selected for its mechanical durability is terminated with a small form factor molded lens assembly which interfaces between an 850nm VCSEL transmitter and a receiving device on the printed circuit board of the display module. A statistical approach based on a Lean Design For Six Sigma (LDFSS) roadmap for new product development tries to find an optimum link definition which will be robust and low cost meeting the power consumption requirements appropriate for battery operated systems.
-
Ragunath, Pk; Abhinand, Pa
2013-01-01
Systems Biology involves the study of the interactions of biological systems and ultimately their functions. Down's syndrome (DS) is one of the most common genetic disorders which are caused by complete, or occasionally partial, triplication of chromosome 21, characterized by cognitive and language dysfunction coupled with sensory and neuromotor deficits. Neural Tube Disorders (NTDs) are a group of congenital malformations of the central nervous system and neighboring structures related to defective neural tube closure during the first trimester of pregnancy usually occurring between days 18-29 of gestation. Several studies in the past have provided considerable evidence that abnormal folate and methyl metabolism are associated with onset of DS & NTDs. There is a possible common etiological pathway for both NTDs and Down's syndrome. But, various research studies over the years have indicated very little evidence for familial link between the two disorders. Our research aimed at the gene expression profiling of microarray datasets pertaining to the two disorders to identify genes whose expression levels are significantly altered in these conditions. The genes which were 1.5 fold unregulated and having a p-value disorders were recognized and over representation analysis was carried out for each of the constituent genes. The comprehensive manual analysis of these genes yields a hypothetical understanding of the lack of familial link between DS and NTDs. There were no genes involved with folic acid present in the dense cliques. Only - CBL, EGFR genes were commonly present, which makes the allelic variants of these genes - good candidates for future studies regarding the familial link between DS and NTDs. NTD - Neural Tube Disorders, DS - Down's Syndrome, MTHFR - Methylenetetrahydrofolate reductase, MTRR- 5 - methyltetrahydrofolate-homocysteine methyltransferase reductase.
-
Tomàs, Josep; Garcia, Neus; Lanuza, Maria A; Santafé, Manel M; Tomàs, Marta; Nadal, Laura; Hurtado, Erica; Simó-Ollé, Anna; Cilleros-Mañé, Víctor; Just-Borràs, Laia
2018-01-01
In the last few years, we have studied the presence and involvement in synaptogenesis and mature transmitter release of the adenosine autoreceptors (AR) in the mammalian neuromuscular junction (NMJ). Here, we review and bring together the previously published data to emphasize the relevance of these receptors for developmental axonal competition, synaptic loss and mature NMJ functional modulation. However, in addition to AR, activity-dependent mediators originating from any of the three cells that make the synapse (nerve, muscle, and glial cells) cross the extracellular cleft to generate signals in target metabotropic receptors. Thus, the integrated interpretation of the complementary function of all these receptors is needed. We previously studied, in the NMJ, the links of AR with mAChR and the neurotrophin receptor TrkB in the control of synapse elimination and transmitter release. We conclude that AR cooperate with these receptors through synergistic and antagonistic effects in the developmental synapse elimination process. In the adult NMJ, this cooperation is manifested so as that the functional integrity of a given receptor group depends on the other receptors operating normally (i.e., the functional integrity of mAChR depends on AR operating normally). These observations underlie the relevance of AR in the NMJ function.
-
Directory of Open Access Journals (Sweden)
Josep Tomàs
2018-04-01
Full Text Available In the last few years, we have studied the presence and involvement in synaptogenesis and mature transmitter release of the adenosine autoreceptors (AR in the mammalian neuromuscular junction (NMJ. Here, we review and bring together the previously published data to emphasize the relevance of these receptors for developmental axonal competition, synaptic loss and mature NMJ functional modulation. However, in addition to AR, activity-dependent mediators originating from any of the three cells that make the synapse (nerve, muscle, and glial cells cross the extracellular cleft to generate signals in target metabotropic receptors. Thus, the integrated interpretation of the complementary function of all these receptors is needed. We previously studied, in the NMJ, the links of AR with mAChR and the neurotrophin receptor TrkB in the control of synapse elimination and transmitter release. We conclude that AR cooperate with these receptors through synergistic and antagonistic effects in the developmental synapse elimination process. In the adult NMJ, this cooperation is manifested so as that the functional integrity of a given receptor group depends on the other receptors operating normally (i.e., the functional integrity of mAChR depends on AR operating normally. These observations underlie the relevance of AR in the NMJ function.
-
Weak but Critical Links between Primary Somatosensory Centers and Motor Cortex during Movement
Directory of Open Access Journals (Sweden)
Pengxu Wei
2018-01-01
Full Text Available Motor performance is improved by stimulation of the agonist muscle during movement. However, related brain mechanisms remain unknown. In this work, we perform a functional magnetic resonance imaging (fMRI study in 21 healthy subjects under three different conditions: (1 movement of right ankle alone; (2 movement and simultaneous stimulation of the agonist muscle; or (3 movement and simultaneous stimulation of a control area. We constructed weighted brain networks for each condition by using functional connectivity. Network features were analyzed using graph theoretical approaches. We found that: (1 the second condition evokes the strongest and most widespread brain activations (5147 vs. 4419 and 2320 activated voxels; and (2 this condition also induces a unique network layout and changes hubs and the modular structure of the brain motor network by activating the most “silent” links between primary somatosensory centers and the motor cortex, particularly weak links from the thalamus to the left primary motor cortex (M1. Significant statistical differences were found when the strength values of the right cerebellum (P < 0.001 or the left thalamus (P = 0.006 were compared among the three conditions. Over the years, studies reported a small number of projections from the thalamus to the motor cortex. This is the first work to present functions of these pathways. These findings reveal mechanisms for enhancing motor function with somatosensory stimulation, and suggest that network function cannot be thoroughly understood when weak ties are disregarded.
-
A biopsychosocial approach to women’s sexual function and dysfunction at midlife: A narrative review
Thomas, Holly N.; Thurston, Rebecca C.
2016-01-01
A satisfying sex life is an important component of overall well-being, but sexual dysfunction is common, especially in midlife women. The aim of this review is (a) to define sexual function and dysfunction, (b) to present theoretical models of female sexual response, (c) to examine longitudinal studies of how sexual function changes during midlife, and (d) to review treatment options. Four types of female sexual dysfunction are currently recognized: Female Orgasmic Disorder, Female Sexual Interest/Arousal Disorder, Genito-Pelvic Pain/Penetration Disorder, and Substance/Medication-Induced Sexual Dysfunction. However, optimal sexual function transcends the simple absence of dysfunction. A biopsychosocial approach that simultaneously considers physical, psychological, sociocultural, and interpersonal factors is necessary to guide research and clinical care regarding women’s sexual function. Most longitudinal studies reveal an association between advancing menopause status and worsening sexual function. Psychosocial variables, such as availability of a partner, relationship quality, and psychological functioning, also play an integral role. Future directions for research should include deepening our understanding of how sexual function changes with aging and developing safe and effective approaches to optimizing women’s sexual function with aging. Overall, holistic, biopsychosocial approaches to women’s sexual function are necessary to fully understand and treat this key component of midlife women’s well-being. PMID:27013288
-
Davies, Patrick T.; Sturge-Apple, Melissa L.; Cicchetti, Dante; Manning, Liviah G.; Zale, Emily
2009-01-01
Background This paper examined children’s fearful, sad, and angry reactivity to interparental conflict as mediators of associations between their exposure to interparental aggression and physiological functioning. Methods Participants included 200 toddlers and their mothers. Assessments of interparental aggression and children’s emotional reactivity were derived from maternal surveys and a semi-structured interview. Cortisol levels and cardiac indices of sympathetic nervous system (SNS) and parasympathetic nervous system (PNS) activity were used to assess toddler physiological functioning. Results Results indicated that toddler exposure to interparental aggression was associated with greater cortisol levels and PNS activity and diminished SNS activity. Toddler angry emotional reactivity mediated associations between interparental aggression and cortisol and PNS functioning. Fearful emotional reactivity was a mediator of the link between interparental aggression and SNS functioning. Conclusions The results are interpreted within conceptualizations of how exposure and reactivity to family risk organizing individual differences in physiological functioning. PMID:19744183
-
Shiba, K; Sugiyama, T; Takei, T; Yoshikawa, G
2015-11-11
Silica/titania-based functional nanoparticles were prepared through controlled nucleation of titania and subsequent encapsulation by silica through a multistep microfluidic approach, which was successfully applied to obtaining aminopropyl-functionalized silica/titania nanoparticles for a highly sensitive humidity sensor.
-
REDEN: Named Entity Linking in Digital Literary Editions Using Linked Data Sets
Directory of Open Access Journals (Sweden)
Carmen Brando
2016-07-01
Full Text Available This paper proposes a graph-based Named Entity Linking (NEL algorithm named REDEN for the disambiguation of authors’ names in French literary criticism texts and scientific essays from the 19th and early 20th centuries. The algorithm is described and evaluated according to the two phases of NEL as reported in current state of the art, namely, candidate retrieval and candidate selection. REDEN leverages knowledge from different Linked Data sources in order to select candidates for each author mention, subsequently crawls data from other Linked Data sets using equivalence links (e.g., owl:sameAs, and, finally, fuses graphs of homologous individuals into a non-redundant graph well-suited for graph centrality calculation; the resulting graph is used for choosing the best referent. The REDEN algorithm is distributed in open-source and follows current standards in digital editions (TEI and semantic Web (RDF. Its integration into an editorial workflow of digital editions in Digital humanities and cultural heritage projects is entirely plausible. Experiments are conducted along with the corresponding error analysis in order to test our approach and to help us to study the weaknesses and strengths of our algorithm, thereby to further improvements of REDEN.
-
Bayne, Michael G; Scher, Jeremy A; Ellis, Benjamin H; Chakraborty, Arindam
2018-05-21
Electron-hole or quasiparticle representation plays a central role in describing electronic excitations in many-electron systems. For charge-neutral excitation, the electron-hole interaction kernel is the quantity of interest for calculating important excitation properties such as optical gap, optical spectra, electron-hole recombination and electron-hole binding energies. The electron-hole interaction kernel can be formally derived from the density-density correlation function using both Green's function and TDDFT formalism. The accurate determination of the electron-hole interaction kernel remains a significant challenge for precise calculations of optical properties in the GW+BSE formalism. From the TDDFT perspective, the electron-hole interaction kernel has been viewed as a path to systematic development of frequency-dependent exchange-correlation functionals. Traditional approaches, such as MBPT formalism, use unoccupied states (which are defined with respect to Fermi vacuum) to construct the electron-hole interaction kernel. However, the inclusion of unoccupied states has long been recognized as the leading computational bottleneck that limits the application of this approach for larger finite systems. In this work, an alternative derivation that avoids using unoccupied states to construct the electron-hole interaction kernel is presented. The central idea of this approach is to use explicitly correlated geminal functions for treating electron-electron correlation for both ground and excited state wave functions. Using this ansatz, it is derived using both diagrammatic and algebraic techniques that the electron-hole interaction kernel can be expressed only in terms of linked closed-loop diagrams. It is proved that the cancellation of unlinked diagrams is a consequence of linked-cluster theorem in real-space representation. The electron-hole interaction kernel derived in this work was used to calculate excitation energies in many-electron systems and results
-
Wavelet approach to accelerator problems. 3: Melnikov functions and symplectic topology
International Nuclear Information System (INIS)
Fedorova, A.; Zeitlin, M.; Parsa, Z.
1997-05-01
This is the third part of a series of talks in which the authors present applications of methods of wavelet analysis to polynomial approximations for a number of accelerator physics problems. They consider the generalization of the variational wavelet approach to nonlinear polynomial problems to the case of Hamiltonian systems for which they need to preserve underlying symplectic or Poissonian or quasicomplex structures in any type of calculations. They use the approach for the problem of explicit calculations of Arnold-Weinstein curves via Floer variational approach from symplectic topology. The loop solutions are parameterized by the solutions of reduced algebraical problem--matrix Quadratic Mirror Filters equations. Also they consider wavelet approach to the calculations of Melnikov functions in the theory of homoclinic chaos in perturbed Hamiltonian systems
-
Directory of Open Access Journals (Sweden)
David S. Boukal
2014-04-01
Full Text Available Biotic interactions in aquatic communities are dominated by predation, and the distribution of trophic link strengths in aquatic food webs crucially impacts their dynamics and stability. Although individual body size explains a large proportion of variation in trophic link strengths in aquatic habitats, current predominately body size-based views can gain additional realism by incorporating further traits. Functional traits that potentially affect the strength of trophic links can be classified into three groups: i body size, ii traits that identify the spatiotemporal overlap between the predators and their prey, and iii predator foraging and prey vulnerability traits, which are readily available for many taxa. Relationship between these trait groups and trophic link strength may be further modified by population densities, habitat complexity, temperature and other abiotic factors. I propose here that this broader multi-trait framework can utilize concepts, ideas and existing data from research on metabolic ecology, ecomorphology, animal personalities and role of habitats in community structuring. The framework can be used to investigate non-additive effects of traits on trophic interactions, shed more light on the structuring of local food webs and evaluate the merits of taxonomic and functional group approaches in the description of predator-prey interactions. Development of trait- and size-based descriptions of food webs could be particularly fruitful in limnology given the relative paucity of well resolved datasets in standing waters.
-
Alnajjar, Mohammad Ahmad; Ramette, Alban; Kü hl, Michael; Hamza, Waleed; Klatt, Judith M.; Polerecky, Lubos
2014-01-01
We imaged reflectance and variable fluorescence in 25 cyanobacterial mats from four distant sites around the globe to assess, at different scales of resolution, spatial variabilities in the physiological parameters characterizing their photosynthetic capacity, including the absorptivity by chlorophyll a (Achl), maximum quantum yield of photosynthesis (Ymax), and light acclimation irradiance (Ik). Generally, these parameters significantly varied within individual mats on a sub-millimeter scale, with about 2-fold higher variability in the vertical than in the horizontal direction. The average vertical profiles of Ymax and Ik decreased with depth in the mat, while Achl exhibited a sub-surface maximum. The within-mat variability was comparable to, but often larger than, the between-sites variability, whereas the within-site variabilities (i.e., between samples from the same site) were generally lowest. When compared based on averaged values of their photosynthetic parameters, mats clustered according to their site of origin. Similar clustering was found when the community composition of the mats' cyanobacterial layers were compared by automated ribosomal intergenic spacer analysis (ARISA), indicating a significant link between the microbial community composition and function. Although this link is likely the result of community adaptation to the prevailing site-specific environmental conditions, our present data is insufficient to identify the main factors determining these patterns. Nevertheless, this study demonstrates that the spatial variability in the photosynthetic capacity and light acclimation of benthic phototrophic microbial communities is at least as large on a sub-millimeter scale as it is on a global scale, and suggests that this pattern of variability scaling is similar for the microbial community composition. © 2014 Al-Najjar, Ramette, Kühl, Hamza, Klatt and Polerecky.
-
Alnajjar, Mohammad Ahmad
2014-08-06
We imaged reflectance and variable fluorescence in 25 cyanobacterial mats from four distant sites around the globe to assess, at different scales of resolution, spatial variabilities in the physiological parameters characterizing their photosynthetic capacity, including the absorptivity by chlorophyll a (Achl), maximum quantum yield of photosynthesis (Ymax), and light acclimation irradiance (Ik). Generally, these parameters significantly varied within individual mats on a sub-millimeter scale, with about 2-fold higher variability in the vertical than in the horizontal direction. The average vertical profiles of Ymax and Ik decreased with depth in the mat, while Achl exhibited a sub-surface maximum. The within-mat variability was comparable to, but often larger than, the between-sites variability, whereas the within-site variabilities (i.e., between samples from the same site) were generally lowest. When compared based on averaged values of their photosynthetic parameters, mats clustered according to their site of origin. Similar clustering was found when the community composition of the mats\\' cyanobacterial layers were compared by automated ribosomal intergenic spacer analysis (ARISA), indicating a significant link between the microbial community composition and function. Although this link is likely the result of community adaptation to the prevailing site-specific environmental conditions, our present data is insufficient to identify the main factors determining these patterns. Nevertheless, this study demonstrates that the spatial variability in the photosynthetic capacity and light acclimation of benthic phototrophic microbial communities is at least as large on a sub-millimeter scale as it is on a global scale, and suggests that this pattern of variability scaling is similar for the microbial community composition. © 2014 Al-Najjar, Ramette, Kühl, Hamza, Klatt and Polerecky.
-
Organization of extracting molecules of the diamide type: link with the extracting properties?
International Nuclear Information System (INIS)
Meridiano, Y.
2009-02-01
The aim of these studies is to establish a link between the different organizations of diamide extractants (used in the DIAMEX process) and their extracting properties. The effects of the key parameters leading the liquid-liquid extraction (concentration of extractant, nature of solute, activity of the aqueous phase, nature of the diluent and temperature) are studied: 1) at the supramolecular scale, with the characterization of the extractant organizations by vapor-pressure osmometry (VPO) and small angle neutron and X-ray scattering (SANS/SAXS) experiments; 2) at the molecular scale, with the quantification of the extracted solutes (water, nitric acid, metal nitrate) and the determination of extracted complexes stoichiometries by electro-spray mass spectrometry (ESI-MS) experiments. The DMDOHEMA molecule acts as a classical surfactant and forms aggregates of the reverse micelle type. Taking into account the established supramolecular diagrams, a quantitative link between the extractants structures and their extracting properties has been brought to light. To model the europium nitrate extraction, two approaches have been developed: - an approach based on mass action laws. Extractions equilibria have been proposed taking into account the supramolecular speciation; - an innovative approach considering the extracted ions as adsorbed on a specific surface of the extractant molecule which depends on the extractant organization state. The ion extraction can be considered as a sum of isotherms corresponding to the different states of organization. This approach allows to compare the extraction efficiency of an extracting molecule as a function of its organization state. (author)
-
Directory of Open Access Journals (Sweden)
Bo-Xue Tian
2014-10-01
Full Text Available Terpenoid synthases construct the carbon skeletons of tens of thousands of natural products. To predict functions and specificity of triterpenoid synthases, a mechanism-based, multi-intermediate docking approach is proposed. In addition to enzyme function prediction, other potential applications of the current approach, such as enzyme mechanistic studies and enzyme redesign by mutagenesis, are discussed.
-
Bonduelle, Colin V; Lau, Woon M; Gillies, Elizabeth R
2011-05-01
The functionalization of surfaces with poly(ethylene oxide) (PEO) is an effective means of imparting resistance to the adsorption of proteins and the attachment and growth of cells, properties that are critical for many biomedical applications. In this work, a new hyperthermal hydrogen induced cross-linking (HHIC) method was explored as a simple one-step approach for attaching PEO to surfaces through the selective cleavage of C-H bonds and subsequent cross-linking of the resulting carbon radicals. In order to study the effects of the process on the polymer, PEO-coated silicon wafers were prepared and the effects of different treatment times were investigated. Subsequently, using an optimized treatment time and a modified butyl polymer with increased affinity for PEO, the technique was applied to butyl rubber surfaces. All of the treated surfaces exhibited significantly reduced protein adsorption and cell growth relative to control surfaces and compared favorably with surfaces that were functionalized with PEO using conventional chemical methods. Thus HHIC is a simple and effective means of attaching PEO to non-functional polymer surfaces.
-
Directory of Open Access Journals (Sweden)
Bighnaraj Naik
2018-01-01
Full Text Available All the higher order ANNs (HONNs including functional link ANN (FLANN are sensitive to random initialization of weight and rely on the learning algorithms adopted. Although a selection of efficient learning algorithms for HONNs helps to improve the performance, on the other hand, initialization of weights with optimized weights rather than random weights also play important roles on its efficiency. In this paper, the problem solving approach of the teaching learning based optimization (TLBO along with learning ability of the gradient descent learning (GDL is used to obtain the optimal set of weight of FLANN learning model. TLBO does not require any specific parameters rather it requires only some of the common independent parameters like number of populations, number of iterations and stopping criteria, thereby eliminating the intricacy in selection of algorithmic parameters for adjusting the set of weights of FLANN model. The proposed TLBO-FLANN is implemented in MATLAB and compared with GA-FLANN, PSO-FLANN and HS-FLANN. The TLBO-FLANN is tested on various 5-fold cross validated benchmark data sets from UCI machine learning repository and analyzed under the null-hypothesis by using Friedman test, Holm’s procedure and post hoc ANOVA statistical analysis (Tukey test & Dunnett test.
-
DEFF Research Database (Denmark)
Krebs, Frederik C; Hagemann, O.; Jørgensen, M.
2004-01-01
A synthetic approach to the synthesis of a large super molecule composed of two chemically different conducting polymer blocks with, respectively, high and low lying electronic energy levels linked through a porphyrin dye molecule is presented. The synthetic strategies to these molecular architec...
-
A simple structure wavelet transform circuit employing function link neural networks and SI filters
Mu, Li; Yigang, He
2016-12-01
Signal processing by means of analog circuits offers advantages from a power consumption viewpoint. Implementing wavelet transform (WT) using analog circuits is of great interest when low-power consumption becomes an important issue. In this article, a novel simple structure WT circuit in analog domain is presented by employing functional link neural network (FLNN) and switched-current (SI) filters. First, the wavelet base is approximated using FLNN algorithms for giving a filter transfer function that is suitable for simple structure WT circuit implementation. Next, the WT circuit is constructed with the wavelet filter bank, whose impulse response is the approximated wavelet and its dilations. The filter design that follows is based on a follow-the-leader feedback (FLF) structure with multiple output bilinear SI integrators and current mirrors as the main building blocks. SI filter is well suited for this application since the dilation constant across different scales of the transform can be precisely implemented and controlled by the clock frequency of the circuit with the same system architecture. Finally, to illustrate the design procedure, a seventh-order FLNN-approximated Gaussian wavelet is implemented as an example. Simulations have successfully verified that the designed simple structure WT circuit has low sensitivity, low-power consumption and litter effect to the imperfections.
-
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
-
Cascade of links in complex networks
Energy Technology Data Exchange (ETDEWEB)
Feng, Yeqian; Sun, Bihui [Department of Management Science, School of Government, Beijing Normal University, 100875 Beijing (China); Zeng, An, E-mail: anzeng@bnu.edu.cn [School of Systems Science, Beijing Normal University, 100875 Beijing (China)
2017-01-30
Cascading failure is an important process which has been widely used to model catastrophic events such as blackouts and financial crisis in real systems. However, so far most of the studies in the literature focus on the cascading process on nodes, leaving the possibility of link cascade overlooked. In many real cases, the catastrophic events are actually formed by the successive disappearance of links. Examples exist in the financial systems where the firms and banks (i.e. nodes) still exist but many financial trades (i.e. links) are gone during the crisis, and the air transportation systems where the airports (i.e. nodes) are still functional but many airlines (i.e. links) stop operating during bad weather. In this letter, we develop a link cascade model in complex networks. With this model, we find that both artificial and real networks tend to collapse even if a few links are initially attacked. However, the link cascading process can be effectively terminated by setting a few strong nodes in the network which do not respond to any link reduction. Finally, a simulated annealing algorithm is used to optimize the location of these strong nodes, which significantly improves the robustness of the networks against the link cascade. - Highlights: • We propose a link cascade model in complex networks. • Both artificial and real networks tend to collapse even if a few links are initially attacked. • The link cascading process can be effectively terminated by setting a few strong nodes. • A simulated annealing algorithm is used to optimize the location of these strong nodes.
-
Cascade of links in complex networks
International Nuclear Information System (INIS)
Feng, Yeqian; Sun, Bihui; Zeng, An
2017-01-01
Cascading failure is an important process which has been widely used to model catastrophic events such as blackouts and financial crisis in real systems. However, so far most of the studies in the literature focus on the cascading process on nodes, leaving the possibility of link cascade overlooked. In many real cases, the catastrophic events are actually formed by the successive disappearance of links. Examples exist in the financial systems where the firms and banks (i.e. nodes) still exist but many financial trades (i.e. links) are gone during the crisis, and the air transportation systems where the airports (i.e. nodes) are still functional but many airlines (i.e. links) stop operating during bad weather. In this letter, we develop a link cascade model in complex networks. With this model, we find that both artificial and real networks tend to collapse even if a few links are initially attacked. However, the link cascading process can be effectively terminated by setting a few strong nodes in the network which do not respond to any link reduction. Finally, a simulated annealing algorithm is used to optimize the location of these strong nodes, which significantly improves the robustness of the networks against the link cascade. - Highlights: • We propose a link cascade model in complex networks. • Both artificial and real networks tend to collapse even if a few links are initially attacked. • The link cascading process can be effectively terminated by setting a few strong nodes. • A simulated annealing algorithm is used to optimize the location of these strong nodes.
-
Capacity-Approaching Superposition Coding for Optical Fiber Links
DEFF Research Database (Denmark)
Estaran Tolosa, Jose Manuel; Zibar, Darko; Tafur Monroy, Idelfonso
2014-01-01
We report on the first experimental demonstration of superposition coded modulation (SCM) for polarization-multiplexed coherent-detection optical fiber links. The proposed coded modulation scheme is combined with phase-shifted bit-to-symbol mapping (PSM) in order to achieve geometric and passive......-SCM) is employed in the framework of bit-interleaved coded modulation with iterative decoding (BICM-ID) for forward error correction. The fiber transmission system is characterized in terms of signal-to-noise ratio for back-to-back case and correlated with simulated results for ideal transmission over additive...... white Gaussian noise channel. Thereafter, successful demodulation and decoding after dispersion-unmanaged transmission over 240-km standard single mode fiber of dual-polarization 6-Gbaud 16-, 32- and 64-ary SCM-PSM is experimentally demonstrated....
-
National Research Council Canada - National Science Library
Noble, Chris
2004-01-01
The Hydrogeomophic (HGM) Approach is a method for developing functional indices and the protocols used to apply these indices to the assessment of wetland functions at a site-specific scale The HGM Approach was initially...
-
Directory of Open Access Journals (Sweden)
Ulf Hensen
Full Text Available Proteins are usually described and classified according to amino acid sequence, structure or function. Here, we develop a minimally biased scheme to compare and classify proteins according to their internal mobility patterns. This approach is based on the notion that proteins not only fold into recurring structural motifs but might also be carrying out only a limited set of recurring mobility motifs. The complete set of these patterns, which we tentatively call the dynasome, spans a multi-dimensional space with axes, the dynasome descriptors, characterizing different aspects of protein dynamics. The unique dynamic fingerprint of each protein is represented as a vector in the dynasome space. The difference between any two vectors, consequently, gives a reliable measure of the difference between the corresponding protein dynamics. We characterize the properties of the dynasome by comparing the dynamics fingerprints obtained from molecular dynamics simulations of 112 proteins but our approach is, in principle, not restricted to any specific source of data of protein dynamics. We conclude that: 1. the dynasome consists of a continuum of proteins, rather than well separated classes. 2. For the majority of proteins we observe strong correlations between structure and dynamics. 3. Proteins with similar function carry out similar dynamics, which suggests a new method to improve protein function annotation based on protein dynamics.
-
Memory function approach to the line shape problem in collision-induced light scattering
International Nuclear Information System (INIS)
Balucani, U.; Tognetti, V.; Vallauri, R.
1980-01-01
This article mainly deals with the problem of the shape of the spectrum due to interacting pairs of atoms at low and moderate densities. A memory function approach is used which permits to obtain in a consistent way the shape of the scattered spectrum. In order to obtain 'exact' time correlation functions and spectral shapes, molecular-dynamics 'experiments' in Lennard-Jones argon at two different densities were also performed. The dipole-induced dipole (DID) polarizabilities have been used to ascertain the validity of the theoretical approach in a well-defined physical model. The theoretical shapes and correlation functions can be then directly compared with computer simulations. Finally, a comparison with the data of real experiments clarifies the relevance of other-than-DID polarizability mechanisms as far as the spectrum is concerned. (KBE)
-
Fluorescence imaging of tryptophan and collagen cross-links to evaluate wound closure ex vivo
Wang, Ying; Ortega-Martinez, Antonio; Farinelli, Bill; Anderson, R. R.; Franco, Walfre
2016-02-01
Wound size is a key parameter in monitoring healing. Current methods to measure wound size are often subjective, time-consuming and marginally invasive. Recently, we developed a non-invasive, non-contact, fast and simple but robust fluorescence imaging (u-FEI) method to monitor the healing of skin wounds. This method exploits the fluorescence of native molecules to tissue as functional and structural markers. The objective of the present study is to demonstrate the feasibility of using variations in the fluorescence intensity of tryptophan and cross-links of collagen to evaluate proliferation of keratinocyte cells and quantitate size of wound during healing, respectively. Circular dermal wounds were created in ex vivo human skin and cultured in different media. Two serial fluorescence images of tryptophan and collagen cross-links were acquired every two days. Histology and immunohistology were used to validate correlation between fluorescence and epithelialization. Images of collagen cross-links show fluorescence of the exposed dermis and, hence, are a measure of wound area. Images of tryptophan show higher fluorescence intensity of proliferating keratinocytes forming new epithelium, as compared to surrounding keratinocytes not involved in epithelialization. These images are complementary since collagen cross-links report on structure while tryptophan reports on function. HE and immunohistology show that tryptophan fluorescence correlates with newly formed epidermis. We have established a fluorescence imaging method for studying epithelialization processes during wound healing in a skin organ culture model, our approach has the potential to provide a non-invasive, non-contact, quick, objective and direct method for quantitative measurements in wound healing in vivo.
-
O'Neil, Edward B; Newsome, Rachel N; Li, Iris H N; Thavabalasingam, Sathesan; Ito, Rutsuko; Lee, Andy C H
2015-11-11
Rodent models of anxiety have implicated the ventral hippocampus in approach-avoidance conflict processing. Few studies have, however, examined whether the human hippocampus plays a similar role. We developed a novel decision-making paradigm to examine neural activity when participants made approach/avoidance decisions under conditions of high or absent approach-avoidance conflict. Critically, our task required participants to learn the associated reward/punishment values of previously neutral stimuli and controlled for mnemonic and spatial processing demands, both important issues given approach-avoidance behavior in humans is less tied to predation and foraging compared to rodents. Participants played a points-based game where they first attempted to maximize their score by determining which of a series of previously neutral image pairs should be approached or avoided. During functional magnetic resonance imaging, participants were then presented with novel pairings of these images. These pairings consisted of images of congruent or opposing learned valences, the latter creating conditions of high approach-avoidance conflict. A data-driven partial least squares multivariate analysis revealed two reliable patterns of activity, each revealing differential activity in the anterior hippocampus, the homolog of the rodent ventral hippocampus. The first was associated with greater hippocampal involvement during trials with high as opposed to no approach-avoidance conflict, regardless of approach or avoidance behavior. The second pattern encompassed greater hippocampal activity in a more anterior aspect during approach compared to avoid responses, for conflict and no-conflict conditions. Multivoxel pattern classification analyses yielded converging findings, underlining a role of the anterior hippocampus in approach-avoidance conflict decision making. Approach-avoidance conflict has been linked to anxiety and occurs when a stimulus or situation is associated with reward
-
Instantaneous thermal modeling of the DC-link capacitor in PhotoVoltaic systems
DEFF Research Database (Denmark)
Yang, Yongheng; Ma, Ke; Wang, Huai
2015-01-01
, instantaneous thermal modeling approaches considering mission profiles for the DC-link capacitor in single-phase PV systems are explored in this paper. These thermal modelling approaches are based on: a) fast Fourier transform, b) look-up tables, and c) ripple current reconstruction. Moreover, the thermal...... grid-connected PV system have been adopted to demonstrate a look-up table based modelling approach, where real-field daily ambient conditions are considered....... modelling approaches for the DC-link capacitors take into account the instantaneous thermal characteristics, which are more challenging to the capacitor reliability during operation. Such instantaneous thermal modeling approaches enable a translation of instantaneous capacitor power losses to capacitor...
-
Effects of multi-state links in network community detection
International Nuclear Information System (INIS)
Rocco, Claudio M.; Moronta, José; Ramirez-Marquez, José E.; Barker, Kash
2017-01-01
A community is defined as a group of nodes of a network that are densely interconnected with each other but only sparsely connected with the rest of the network. The set of communities (i.e., the network partition) and their inter-community links could be derived using special algorithms account for the topology of the network and, in certain cases, the possible weights associated to the links. In general, the set of weights represents some characteristic as capacity, flow and reliability, among others. The effects of considering weights could be translated to obtain a different partition. In many real situations, particularly when modeling infrastructure systems, networks must be modeled as multi-state networks (e.g., electric power networks). In such networks, each link is characterized by a vector of known random capacities (i.e., the weight on each link could vary according to a known probability distribution). In this paper a simple Monte Carlo approach is proposed to evaluate the effects of multi-state links on community detection as well as on the performance of the network. The approach is illustrated with the topology of an electric power system. - Highlights: • Identify network communities when considering multi-state links. • Identified how effects of considering weights translate to different partition. • Identified importance of Inter-Community Links and changes with respect to community. • Preamble to performing a resilience assessment able to mimic the evolution of the state of each community.
-
Joint brain connectivity estimation from diffusion and functional MRI data
Chu, Shu-Hsien; Lenglet, Christophe; Parhi, Keshab K.
2015-03-01
Estimating brain wiring patterns is critical to better understand the brain organization and function. Anatomical brain connectivity models axonal pathways, while the functional brain connectivity characterizes the statistical dependencies and correlation between the activities of various brain regions. The synchronization of brain activity can be inferred through the variation of blood-oxygen-level dependent (BOLD) signal from functional MRI (fMRI) and the neural connections can be estimated using tractography from diffusion MRI (dMRI). Functional connections between brain regions are supported by anatomical connections, and the synchronization of brain activities arises through sharing of information in the form of electro-chemical signals on axon pathways. Jointly modeling fMRI and dMRI data may improve the accuracy in constructing anatomical connectivity as well as functional connectivity. Such an approach may lead to novel multimodal biomarkers potentially able to better capture functional and anatomical connectivity variations. We present a novel brain network model which jointly models the dMRI and fMRI data to improve the anatomical connectivity estimation and extract the anatomical subnetworks associated with specific functional modes by constraining the anatomical connections as structural supports to the functional connections. The key idea is similar to a multi-commodity flow optimization problem that minimizes the cost or maximizes the efficiency for flow configuration and simultaneously fulfills the supply-demand constraint for each commodity. In the proposed network, the nodes represent the grey matter (GM) regions providing brain functionality, and the links represent white matter (WM) fiber bundles connecting those regions and delivering information. The commodities can be thought of as the information corresponding to brain activity patterns as obtained for instance by independent component analysis (ICA) of fMRI data. The concept of information
-
A Multivariate Quality Loss Function Approach for Optimization of Spinning Processes
Chakraborty, Shankar; Mitra, Ankan
2018-05-01
Recent advancements in textile industry have given rise to several spinning techniques, such as ring spinning, rotor spinning etc., which can be used to produce a wide variety of textile apparels so as to fulfil the end requirements of the customers. To achieve the best out of these processes, they should be utilized at their optimal parametric settings. However, in presence of multiple yarn characteristics which are often conflicting in nature, it becomes a challenging task for the spinning industry personnel to identify the best parametric mix which would simultaneously optimize all the responses. Hence, in this paper, the applicability of a new systematic approach in the form of multivariate quality loss function technique is explored for optimizing multiple quality characteristics of yarns while identifying the ideal settings of two spinning processes. It is observed that this approach performs well against the other multi-objective optimization techniques, such as desirability function, distance function and mean squared error methods. With slight modifications in the upper and lower specification limits of the considered quality characteristics, and constraints of the non-linear optimization problem, it can be successfully applied to other processes in textile industry to determine their optimal parametric settings.
-
Farzaneh, Saeed; Forootan, Ehsan
2018-03-01
The computerized ionospheric tomography is a method for imaging the Earth's ionosphere using a sounding technique and computing the slant total electron content (STEC) values from data of the global positioning system (GPS). The most common approach for ionospheric tomography is the voxel-based model, in which (1) the ionosphere is divided into voxels, (2) the STEC is then measured along (many) satellite signal paths, and finally (3) an inversion procedure is applied to reconstruct the electron density distribution of the ionosphere. In this study, a computationally efficient approach is introduced, which improves the inversion procedure of step 3. Our proposed method combines the empirical orthogonal function and the spherical Slepian base functions to describe the vertical and horizontal distribution of electron density, respectively. Thus, it can be applied on regional and global case studies. Numerical application is demonstrated using the ground-based GPS data over South America. Our results are validated against ionospheric tomography obtained from the constellation observing system for meteorology, ionosphere, and climate (COSMIC) observations and the global ionosphere map estimated by international centers, as well as by comparison with STEC derived from independent GPS stations. Using the proposed approach, we find that while using 30 GPS measurements in South America, one can achieve comparable accuracy with those from COSMIC data within the reported accuracy (1 × 1011 el/cm3) of the product. Comparisons with real observations of two GPS stations indicate an absolute difference is less than 2 TECU (where 1 total electron content unit, TECU, is 1016 electrons/m2).
-
A functional data analysis approach for genetic association studies
Reimherr, Matthew; Nicolae, Dan
2014-01-01
We present a new method based on Functional Data Analysis (FDA) for detecting associations between one or more scalar covariates and a longitudinal response, while correcting for other variables. Our methods exploit the temporal structure of longitudinal data in ways that are otherwise difficult with a multivariate approach. Our procedure, from an FDA perspective, is a departure from more established methods in two key aspects. First, the raw longitudinal phenotypes are assembled into functio...
-
Integrin-linked kinase: a Scaffold protein unique among its ilk.
Dagnino, Lina
2011-06-01
Integrin-linked kinase (ILK) is a scaffolding protein with central roles in tissue development and homeostasis. Much debate has focused on whether ILK is a bona fide or a pseudo- kinase. This aspect of ILK function has been complicated by the large volumes of conflicting observations obtained from a wide variety of experimental approaches, from in vitro models, to analyses in invertebrates and in mammals. Key findings in support or against the notion that ILK is catalytically active are summarized. The importance of ILK as an adaptor protein is well established, and defining its role as a signaling hub will be the next key step to understand its distinct biological roles across tissues and species.
-
Fractal analytical approach of urban form based on spatial correlation function
International Nuclear Information System (INIS)
Chen, Yanguang
2013-01-01
Highlights: ► Many fractal parameter relations of cities can be derived by scaling analysis. ► The area-radius scaling of cities suggests a spatial correlation function. ► Spectral analysis can be used to estimate fractal dimension values of urban form. ► The valid range of fractal dimension of urban form comes between 1.5 and 2. ► The traditional scale concept will be replaced by scaling concept in geography. -- Abstract: Urban form has been empirically demonstrated to be of scaling invariance and can be described with fractal geometry. However, the rational range of fractal dimension value and the relationships between various fractal indicators of cities are not yet revealed in theory. By mathematical deduction and transform (e.g., Fourier transform), I find that scaling analysis, spectral analysis, and spatial correlation analysis are all associated with fractal concepts and can be integrated into a new approach to fractal analysis of cities. This method can be termed ‘3S analyses’ of urban form. Using the 3S analysis, I derived a set of fractal parameter equations, by which different fractal parameters of cities can be linked up with one another. Each fractal parameter has its own reasonable extent of values. According to the fractal parameter equations, the intersection of the rational ranges of different fractal parameters suggests the proper scale of the fractal dimension of urban patterns, which varies from 1.5 to 2. The fractal dimension equations based on the 3S analysis and the numerical relationships between different fractal parameters are useful for geographers to understand urban evolution and potentially helpful for future city planning
-
Extracting functionally feedforward networks from a population of spiking neurons.
Vincent, Kathleen; Tauskela, Joseph S; Thivierge, Jean-Philippe
2012-01-01
Neuronal avalanches are a ubiquitous form of activity characterized by spontaneous bursts whose size distribution follows a power-law. Recent theoretical models have replicated power-law avalanches by assuming the presence of functionally feedforward connections (FFCs) in the underlying dynamics of the system. Accordingly, avalanches are generated by a feedforward chain of activation that persists despite being embedded in a larger, massively recurrent circuit. However, it is unclear to what extent networks of living neurons that exhibit power-law avalanches rely on FFCs. Here, we employed a computational approach to reconstruct the functional connectivity of cultured cortical neurons plated on multielectrode arrays (MEAs) and investigated whether pharmacologically induced alterations in avalanche dynamics are accompanied by changes in FFCs. This approach begins by extracting a functional network of directed links between pairs of neurons, and then evaluates the strength of FFCs using Schur decomposition. In a first step, we examined the ability of this approach to extract FFCs from simulated spiking neurons. The strength of FFCs obtained in strictly feedforward networks diminished monotonically as links were gradually rewired at random. Next, we estimated the FFCs of spontaneously active cortical neuron cultures in the presence of either a control medium, a GABA(A) receptor antagonist (PTX), or an AMPA receptor antagonist combined with an NMDA receptor antagonist (APV/DNQX). The distribution of avalanche sizes in these cultures was modulated by this pharmacology, with a shallower power-law under PTX (due to the prominence of larger avalanches) and a steeper power-law under APV/DNQX (due to avalanches recruiting fewer neurons) relative to control cultures. The strength of FFCs increased in networks after application of PTX, consistent with an amplification of feedforward activity during avalanches. Conversely, FFCs decreased after application of APV
-
Sensorimotor integration for functional recovery and the Bobath approach.
Levin, Mindy F; Panturin, Elia
2011-04-01
Bobath therapy is used to treat patients with neurological disorders. Bobath practitioners use hands-on approaches to elicit and reestablish typical movement patterns through therapist-controlled sensorimotor experiences within the context of task accomplishment. One aspect of Bobath practice, the recovery of sensorimotor function, is reviewed within the framework of current motor control theories. We focus on the role of sensory information in movement production, the relationship between posture and movement and concepts related to motor recovery and compensation with respect to this therapeutic approach. We suggest that a major barrier to the evaluation of the therapeutic effectiveness of the Bobath concept is the lack of a unified framework for both experimental identification and treatment of neurological motor deficits. More conclusive analysis of therapeutic effectiveness requires the development of specific outcomes that measure movement quality.
-
Functional renormalization group approach to interacting three-dimensional Weyl semimetals
Sharma, Anand; Scammell, Arthur; Krieg, Jan; Kopietz, Peter
2018-03-01
We investigate the effect of long-range Coulomb interaction on the quasiparticle properties and the dielectric function of clean three-dimensional Weyl semimetals at zero temperature using a functional renormalization group (FRG) approach. The Coulomb interaction is represented via a bosonic Hubbard-Stratonovich field which couples to the fermionic density. We derive truncated FRG flow equations for the fermionic and bosonic self-energies and for the three-legged vertices with two fermionic and one bosonic external legs. We consider two different cutoff schemes—cutoff in fermionic or bosonic propagators—in order to calculate the renormalized quasiparticle velocity and the dielectric function for an arbitrary number of Weyl nodes and the interaction strength. If we approximate the dielectric function by its static limit, our results for the velocity and the dielectric function are in good agreement with that of A. A. Abrikosov and S. D. Beneslavskiĭ [Sov. Phys. JETP 32, 699 (1971)] exhibiting slowly varying logarithmic momentum dependence for small momenta. We extend their result for an arbitrary number of Weyl nodes and finite frequency by evaluating the renormalized velocity in the presence of dynamic screening and calculate the wave function renormalization.
-
International Nuclear Information System (INIS)
Cronje, P.B.
1988-01-01
The multitude of different supplements recommended for animals grazing natural pastures, which testifies to the need for a metabolic basis for supplementary feeding practices. The first approach to this problem was to simulate different feeding conditions in the laboratory, where the metabolic responses of body tissues to changes in the supply of purified nutrients could be studied using radioisotope techniques. The second step was to link these fundamental studies to field conditions. The results of these studies suggest that the efficiency of feed conversion and growth rates of ruminants grazing winter pastures in the highveld region of South Africa could be substantially improved by strategic supplementation with glucose precursors. Acetate clearance rate represents a valuable link in the process of applying information obtained from controlled laboratory experiments to field conditions. As this technique is inexpensive, quick and simple to carry out, it is ideally suited to application under field conditions where the use of isotopes is impractical. By providing a link with field conditions, it greatly extended the scope and practical application of isotope tracer techniques
-
An NPARC Turbulence Module with Wall Functions
Zhu, J.; Shih, T.-H.
1997-01-01
The turbulence module recently developed for the NPARC code has been extended to include wall functions. The Van Driest transformation is used so that the wall functions can be applied to both incompressible and compressible flows. The module is equipped with three two-equation K-epsilon turbulence models: Chien, Shih-Lumley and CMOTR models. Details of the wall functions as well as their numerical implementation are reported. It is shown that the inappropriate artificial viscosity in the near-wall region has a big influence on the solution of the wall function approach. A simple way to eliminate this influence is proposed, which gives satisfactory results during the code validation. The module can be easily linked to the NPARC code for practical applications.
-
Atom and Bond Fukui Functions and Matrices: A Hirshfeld-I Atoms-in-Molecule Approach.
Oña, Ofelia B; De Clercq, Olivier; Alcoba, Diego R; Torre, Alicia; Lain, Luis; Van Neck, Dimitri; Bultinck, Patrick
2016-09-19
The Fukui function is often used in its atom-condensed form by isolating it from the molecular Fukui function using a chosen weight function for the atom in the molecule. Recently, Fukui functions and matrices for both atoms and bonds separately were introduced for semiempirical and ab initio levels of theory using Hückel and Mulliken atoms-in-molecule models. In this work, a double partitioning method of the Fukui matrix is proposed within the Hirshfeld-I atoms-in-molecule framework. Diagonalizing the resulting atomic and bond matrices gives eigenvalues and eigenvectors (Fukui orbitals) describing the reactivity of atoms and bonds. The Fukui function is the diagonal element of the Fukui matrix and may be resolved in atom and bond contributions. The extra information contained in the atom and bond resolution of the Fukui matrices and functions is highlighted. The effect of the choice of weight function arising from the Hirshfeld-I approach to obtain atom- and bond-condensed Fukui functions is studied. A comparison of the results with those generated by using the Mulliken atoms-in-molecule approach shows low correlation between the two partitioning schemes. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
-
Fernandes, Catarina G; Plácido, Diana; Lousa, Diana; Brito, José A; Isidro, Anabela; Soares, Cláudio M; Pohl, Jan; Carrondo, Maria A; Archer, Margarida; Henriques, Adriano O
2015-09-22
Transglutaminases are best known for their ability to catalyze protein cross-linking reactions that impart chemical and physical resilience to cellular structures. Here, we report the crystal structure and characterization of Tgl, a transglutaminase from the bacterium Bacillus subtilis. Tgl is produced during sporulation and cross-links the surface of the highly resilient spore. Tgl-like proteins are found only in spore-forming bacteria of the Bacillus and Clostridia classes, indicating an ancient origin. Tgl is a single-domain protein, produced in active form, and the smallest transglutaminase characterized to date. We show that Tgl is structurally similar to bacterial cell wall endopeptidases and has an NlpC/P60 catalytic core, thought to represent the ancestral unit of the cysteine protease fold. We show that Tgl functions through a unique partially redundant catalytic dyad formed by Cys116 and Glu187 or Glu115. Strikingly, the catalytic Cys is insulated within a hydrophobic tunnel that traverses the molecule from side to side. The lack of similarity of Tgl to other transglutaminases together with its small size suggests that an NlpC/P60 catalytic core and insulation of the active site during catalysis may be essential requirements for protein cross-linking.
-
Yokoyama, Yasunori; Tanaka, Hikaru; Yano, Shunsuke; Takahashi, Hiroshi; Kikukawa, Takashi; Sonoyama, Masashi; Takenaka, Koshi
2017-05-01
We previously discovered the correlation between light-induced chromophore color change of a photo-receptor membrane protein bacteriorhodopsin (bR) and its two-dimensional crystalline state in the membrane. To apply this phenomenon to a novel optical memory device, it is necessary that bR molecules are immobilized as maintaining their structure and functional properties. In this work, a poly(vinyl alcohol) (PVA) hydrogel with physical cross-linkages (hydrogen bonds between PVA chains) that resulted from repeated freezing-and-thawing (FT) cycles was used as an immobilization medium. To investigate the effects of physically cross-linked PVA gelation on the structure and function of bR in purple membranes (PMs), spectroscopic techniques were employed against PM/PVA immobilized samples prepared with different FT cycle numbers. Visible circular dichroism spectroscopy strongly suggested PM stacking during gelation. X-ray diffraction data also indicated the PM stacking as well as its native-like crystalline lattice even after gelation. Time-resolved absorption spectroscopy showed that bR photocycle behaviors in PM/PVA immobilized samples were almost identical to that in suspension. These results suggested that a physically cross-linked PVA hydrogel is appropriate for immobilizing membrane proteins in terms of maintaining their structure and functionality.
-
Functional vs. Traditional Analysis in Biomechanical Gait Data: An Alternative Statistical Approach.
Park, Jihong; Seeley, Matthew K; Francom, Devin; Reese, C Shane; Hopkins, J Ty
2017-12-01
In human motion studies, discrete points such as peak or average kinematic values are commonly selected to test hypotheses. The purpose of this study was to describe a functional data analysis and describe the advantages of using functional data analyses when compared with a traditional analysis of variance (ANOVA) approach. Nineteen healthy participants (age: 22 ± 2 yrs, body height: 1.7 ± 0.1 m, body mass: 73 ± 16 kg) walked under two different conditions: control and pain+effusion. Pain+effusion was induced by injection of sterile saline into the joint capsule and hypertonic saline into the infrapatellar fat pad. Sagittal-plane ankle, knee, and hip joint kinematics were recorded and compared following injections using 2×2 mixed model ANOVAs and FANOVAs. The results of ANOVAs detected a condition × time interaction for the peak ankle (F1,18 = 8.56, p = 0.01) and hip joint angle (F1,18 = 5.77, p = 0.03), but did not for the knee joint angle (F1,18 = 0.36, p = 0.56). The functional data analysis, however, found several differences at initial contact (ankle and knee joint), in the mid-stance (each joint) and at toe off (ankle). Although a traditional ANOVA is often appropriate for discrete or summary data, in biomechanical applications, the functional data analysis could be a beneficial alternative. When using the functional data analysis approach, a researcher can (1) evaluate the entire data as a function, and (2) detect the location and magnitude of differences within the evaluated function.
-
Functional vs. Traditional Analysis in Biomechanical Gait Data: An Alternative Statistical Approach
Directory of Open Access Journals (Sweden)
Park Jihong
2017-12-01
Full Text Available In human motion studies, discrete points such as peak or average kinematic values are commonly selected to test hypotheses. The purpose of this study was to describe a functional data analysis and describe the advantages of using functional data analyses when compared with a traditional analysis of variance (ANOVA approach. Nineteen healthy participants (age: 22 ± 2 yrs, body height: 1.7 ± 0.1 m, body mass: 73 ± 16 kg walked under two different conditions: control and pain+effusion. Pain+effusion was induced by injection of sterile saline into the joint capsule and hypertonic saline into the infrapatellar fat pad. Sagittal-plane ankle, knee, and hip joint kinematics were recorded and compared following injections using 2×2 mixed model ANOVAs and FANOVAs. The results of ANOVAs detected a condition × time interaction for the peak ankle (F1,18 = 8.56, p = 0.01 and hip joint angle (F1,18 = 5.77, p = 0.03, but did not for the knee joint angle (F1,18 = 0.36, p = 0.56. The functional data analysis, however, found several differences at initial contact (ankle and knee joint, in the mid-stance (each joint and at toe off (ankle. Although a traditional ANOVA is often appropriate for discrete or summary data, in biomechanical applications, the functional data analysis could be a beneficial alternative. When using the functional data analysis approach, a researcher can (1 evaluate the entire data as a function, and (2 detect the location and magnitude of differences within the evaluated function.
-
Institute of Scientific and Technical Information of China (English)
Jing Liu; Qi-Wei Chen; Kai Wu
2017-01-01
Bottom-up approach to constructing low-dimensional nanostructures on surfaces with terminal alkynes has drawn great interest because of its potential applications in fabricating advanced functional nanomaterials.The diversity of the achieved products manifests rich chemistry of terminal alkynes and hence careful linking strategies and proper controlling methodologies are required for selective preparations of high-quality target nanoarchitectures.This review summarizes various on-surface linking strategies for terminal alkynes,including non-bonding interactions as well as organometallic and covalent bonds,and presents examples to show effective control of surface assemblies and reactions of terminal alkynes by variations of the precursor structures,substrates and activation modes.Systematic studies of the on-surface linkage of terminal alkynes may help efficient and predictable preparations of surface nanomaterials and further understanding of surface chemistry.
-
An approach for functional safety improvement of an existing automotive system
Khabbaz Saberi, A.; Luo, Y.; Pawel Cichosz, F.; Brand, M. van den; Jansen, S.T.H.
2015-01-01
Safety of automotive systems is becoming more involved, specially for the case of autonomous vehicles. The ISO 26262 standard offers a systematic approach for designing a safe road vehicle (or subsystems of a car) from design phase through its production. However, providing functional safety
-
Karvánková, Petra; Popjaková, Dagmar
2018-05-01
Pupil research in school lessons in the sense of Inquiry-Based Education (IBE) is one of the constructivist approaches to education. Inquiry strengthens the positive approach of pupils to natural science subjects, encouraging them to study phenomena and processes taking place in the natural environment around them and use the acquired knowledge in their practical life. Geography as a school subject, due to the multidisciplinary nature of geography as a science, is close to natural sciences as well. This is because of the broadness of the subject of geographical studies, the complex (natural and cultural) landscape. The close links of geography to all cross-sectional themes make it a good support for teaching classical science subjects at schools such as mathematics, physics, chemistry or biology, environmental education. Moreover, the field teaching is one of the strong assets of the implementation of IBE in the school geography. Presented case study on the 'effect of noise on the surroundings' explores the facts mentioned above, in geography teaching. It verifies the pupils' knowledge and skills to adopt the basic principles of IBE in the practice. At the same time, it presents the concrete experiences how the children master the individual stages of IBE during the process of education.
-
Kruyt, F A; Youssoufian, H
1998-10-01
Fanconi anemia (FA) is an autosomal recessive disease characterized by chromosomal instability, bone marrow failure, and a high risk of developing malignancies. Although the disorder is genetically heterogeneous, all FA cells are defined by their sensitivity to the apoptosis-inducing effect of cross-linking agents, such as mitomycin C (MMC). The cloned FA disease genes, FAC and FAA, encode proteins with no homology to each other or to any known protein. We generated a highly specific antibody against FAA and found the protein in both the cytoplasm and nucleus of mammalian cells. By subcellular fractionation, FAA is also associated with intracellular membranes. To identify the subcellular compartment that is relevant for FAA activity, we appended nuclear export and nuclear localization signals to the carboxy terminus of FAA and enriched its localization in either the cytoplasm or the nucleus. Nuclear localization of FAA was both necessary and sufficient to correct MMC sensitivity in FA-A cells. In addition, we found no evidence for an interaction between FAA and FAC either in vivo or in vitro. Together with a previous finding that FAC is active in the cytoplasm but not in the nucleus, our results indicate that FAA and FAC function in separate subcellular compartments. Thus, FAA and FAC, if functionally linked, are more likely to be in a linear pathway rather than form a macromolecular complex to protect against cross-linker cytotoxicity.
-
Hierarchical organization of functional connectivity in the mouse brain: a complex network approach.
Bardella, Giampiero; Bifone, Angelo; Gabrielli, Andrea; Gozzi, Alessandro; Squartini, Tiziano
2016-08-18
This paper represents a contribution to the study of the brain functional connectivity from the perspective of complex networks theory. More specifically, we apply graph theoretical analyses to provide evidence of the modular structure of the mouse brain and to shed light on its hierarchical organization. We propose a novel percolation analysis and we apply our approach to the analysis of a resting-state functional MRI data set from 41 mice. This approach reveals a robust hierarchical structure of modules persistent across different subjects. Importantly, we test this approach against a statistical benchmark (or null model) which constrains only the distributions of empirical correlations. Our results unambiguously show that the hierarchical character of the mouse brain modular structure is not trivially encoded into this lower-order constraint. Finally, we investigate the modular structure of the mouse brain by computing the Minimal Spanning Forest, a technique that identifies subnetworks characterized by the strongest internal correlations. This approach represents a faster alternative to other community detection methods and provides a means to rank modules on the basis of the strength of their internal edges.
-
Androgen receptor function links human sexual dimorphism to DNA methylation.
Directory of Open Access Journals (Sweden)
Ole Ammerpohl
Full Text Available Sex differences are well known to be determinants of development, health and disease. Epigenetic mechanisms are also known to differ between men and women through X-inactivation in females. We hypothesized that epigenetic sex differences may also result from sex hormone functions, in particular from long-lasting androgen programming. We aimed at investigating whether inactivation of the androgen receptor, the key regulator of normal male sex development, is associated with differences of the patterns of DNA methylation marks in genital tissues. To this end, we performed large scale array-based analysis of gene methylation profiles on genomic DNA from labioscrotal skin fibroblasts of 8 males and 26 individuals with androgen insensitivity syndrome (AIS due to inactivating androgen receptor gene mutations. By this approach we identified differential methylation of 167 CpG loci representing 162 unique human genes. These were significantly enriched for androgen target genes and low CpG content promoter genes. Additional 75 genes showed a significant increase of heterogeneity of methylation in AIS compared to a high homogeneity in normal male controls. Our data show that normal and aberrant androgen receptor function is associated with distinct patterns of DNA-methylation marks in genital tissues. These findings support the concept that transcription factor binding to the DNA has an impact on the shape of the DNA methylome. These data which derived from a rare human model suggest that androgen programming of methylation marks contributes to sexual dimorphism in the human which might have considerable impact on the manifestation of sex-associated phenotypes and diseases.
-
Quantum anharmonic oscillator: The airy function approach
Energy Technology Data Exchange (ETDEWEB)
Maiz, F., E-mail: fethimaiz@gmail.com [King Khalid University, Faculty of Science, Physics Department, PO Box 9004, Abha 61413, Asseer (Saudi Arabia); University of Cartage, Nabeul Engineering Preparatory Institute, Merazka, 8000 Nabeul (Tunisia); AlFaify, S. [King Khalid University, Faculty of Science, Physics Department, PO Box 9004, Abha 61413, Asseer (Saudi Arabia)
2014-05-15
New and simple numerical method is being reported to solve anharmonic oscillator problems. The method is setup to approach the real potential V(x) of the anharmonic oscillator system as a piecewise linear potential u(x) and to solve the Schrödinger equation of the system using the Airy function. Then, solutions continuity conditions lead to the energy quantification condition, and consequently, the energy eigenvalues. For testing purpose, the method was applied on the sextic and octic oscillators systems. The proposed method is found to be realistic, computationally simple, and having high degrees of accuracy. In addition, it can be applied to any form of potential. The results obtained by the proposed method were seen closely agreeing with results reached by other complicated methods.
-
Link Label Prediction in Signed Citation Network
Akujuobi, Uchenna
2016-04-12
Link label prediction is the problem of predicting the missing labels or signs of all the unlabeled edges in a network. For signed networks, these labels can either be positive or negative. In recent years, different algorithms have been proposed such as using regression, trust propagation and matrix factorization. These approaches have tried to solve the problem of link label prediction by using ideas from social theories, where most of them predict a single missing label given that labels of other edges are known. However, in most real-world social graphs, the number of labeled edges is usually less than that of unlabeled edges. Therefore, predicting a single edge label at a time would require multiple runs and is more computationally demanding. In this thesis, we look at link label prediction problem on a signed citation network with missing edge labels. Our citation network consists of papers from three major machine learning and data mining conferences together with their references, and edges showing the relationship between them. An edge in our network is labeled either positive (dataset relevant) if the reference is based on the dataset used in the paper or negative otherwise. We present three approaches to predict the missing labels. The first approach converts the label prediction problem into a standard classification problem. We then, generate a set of features for each edge and then adopt Support Vector Machines in solving the classification problem. For the second approach, we formalize the graph such that the edges are represented as nodes with links showing similarities between them. We then adopt a label propagation method to propagate the labels on known nodes to those with unknown labels. In the third approach, we adopt a PageRank approach where we rank the nodes according to the number of incoming positive and negative edges, after which we set a threshold. Based on the ranks, we can infer an edge would be positive if it goes a node above the
-
Pediatrician's knowledge on the approach of functional constipation.
Vieira, Mario C; Negrelle, Isadora Carolina Krueger; Webber, Karla Ulaf; Gosdal, Marjorie; Truppel, Sabine Krüger; Kusma, Solena Ziemer
2016-12-01
To evaluate the pediatrician's knowledge regarding the diagnostic and therapeutic approach of childhood functional constipation. A descriptive cross-sectional study was performed with the application of a self-administered questionnaire concerning a hypothetical clinical case of childhood functional constipation with fecal incontinence to physicians (n=297) randomly interviewed at the 36th Brazilian Congress of Pediatrics in 2013. The majority of the participants were females, the mean age was 44.1 years, the mean time of professional practice was 18.8 years; 56.9% were Board Certified by the Brazilian Society of Pediatrics. Additional tests were ordered by 40.4%; including abdominal radiography (19.5%), barium enema (10.4%), laboratory tests (9.8%), abdominal ultrasound (6.7%), colonoscopy (2.4%), manometry and rectal biopsy (both 1.7%). The most common interventions included lactulose (26.6%), mineral oil (17.5%), polyethylene glycol (14.5%), fiber supplement (9.1%) and milk of magnesia (5.4%). Nutritional guidance (84.8%), fecal disimpaction (17.2%) and toilet training (19.5%) were also indicated. Our results show that pediatricians do not adhere to current recommendations for the management of childhood functional constipation, as unnecessary tests were ordered and the first-line treatment was not prescribed. Copyright © 2016. Publicado por Elsevier Editora Ltda.
-
Pediatrician's knowledge on the approach of functional constipation
Directory of Open Access Journals (Sweden)
Mario C. Vieira
Full Text Available Abstract Objective: To evaluate the pediatrician's knowledge regarding the diagnostic and therapeutic approach of childhood functional constipation. Methods: A descriptive cross-sectional study was performed with the application of a self-administered questionnaire concerning a hypothetical clinical case of childhood functional constipation with fecal incontinence to physicians (n=297 randomly interviewed at the 36th Brazilian Congress of Pediatrics in 2013. Results: The majority of the participants were females, the mean age was 44.1 years, the mean time of professional practice was 18.8 years; 56.9% were Board Certified by the Brazilian Society of Pediatrics. Additional tests were ordered by 40.4%; including abdominal radiography (19.5%, barium enema (10.4%, laboratory tests (9.8%, abdominal ultrasound (6.7%, colonoscopy (2.4%, manometry and rectal biopsy (both 1.7%. The most common interventions included lactulose (26.6%, mineral oil (17.5%, polyethylene glycol (14.5%, fiber supplement (9.1% and milk of magnesia (5.4%. Nutritional guidance (84.8%, fecal disimpaction (17.2% and toilet training (19.5% were also indicated. Conclusions: Our results show that pediatricians do not adhere to current recommendations for the management of childhood functional constipation, as unnecessary tests were ordered and the first-line treatment was not prescribed.
-
Nonlinear Optimization-Based Device-Free Localization with Outlier Link Rejection
Directory of Open Access Journals (Sweden)
Wendong Xiao
2015-04-01
Full Text Available Device-free localization (DFL is an emerging wireless technique for estimating the location of target that does not have any attached electronic device. It has found extensive use in Smart City applications such as healthcare at home and hospitals, location-based services at smart spaces, city emergency response and infrastructure security. In DFL, wireless devices are used as sensors that can sense the target by transmitting and receiving wireless signals collaboratively. Many DFL systems are implemented based on received signal strength (RSS measurements and the location of the target is estimated by detecting the changes of the RSS measurements of the wireless links. Due to the uncertainty of the wireless channel, certain links may be seriously polluted and result in erroneous detection. In this paper, we propose a novel nonlinear optimization approach with outlier link rejection (NOOLR for RSS-based DFL. It consists of three key strategies, including: (1 affected link identification by differential RSS detection; (2 outlier link rejection via geometrical positional relationship among links; (3 target location estimation by formulating and solving a nonlinear optimization problem. Experimental results demonstrate that NOOLR is robust to the fluctuation of the wireless signals with superior localization accuracy compared with the existing Radio Tomographic Imaging (RTI approach.
-
A statistical model for telecommunication link design
Yuen, J. H.
1975-01-01
An evaluation is conducted of the current telecommunication link design technique and a description is presented of an alternative method, called the probability distribution method (PDM), which is free of the disadvantages of the current technique while retaining its advantages. The PDM preserves the simplicity of the design control table (DCT) format. The use of the DCT as a management design control tool is continued. The telecommunication link margin probability density function used presents the probability of achieving any particular value of link performance. It is, therefore, possible to assess the performance risk and other tradeoffs.
-
NARX prediction of some rare chaotic flows: Recurrent fuzzy functions approach
International Nuclear Information System (INIS)
Goudarzi, Sobhan; Jafari, Sajad; Moradi, Mohammad Hassan; Sprott, J.C.
2016-01-01
The nonlinear and dynamic accommodating capability of time domain models makes them a useful representation of chaotic time series for analysis, modeling and prediction. This paper is devoted to the modeling and prediction of chaotic time series with hidden attractors using a nonlinear autoregressive model with exogenous inputs (NARX) based on a novel recurrent fuzzy functions (RFFs) approach. Case studies of recently introduced chaotic systems with hidden attractors plus classical chaotic systems demonstrate that the proposed modeling methodology exhibits better prediction performance from different viewpoints (short term and long term) compared to some other existing methods. - Highlights: • A new method is proposed for prediction of chaotic time series. • This method is based on novel recurrent fuzzy functions (RFFs) approach. • Some rare chaotic flows are used as test systems. • The new method shows proper performance in short-term prediction. • It also shows proper performance in prediction of attractor's topology.
-
Parenting approaches, family functionality, and internet addiction among Hong Kong adolescents.
Wu, Cynthia Sau Ting; Wong, Ho Ting; Yu, Kin Fai; Fok, Ka Wing; Yeung, Sheung Man; Lam, Cheuk Ho; Liu, Ka Man
2016-08-18
Internet addiction (IA) among adolescents has become a global health problem, and public awareness of it is increasing. Many IA risk factors relate to parents and the family environment. This study examined the relationship between IA and parenting approaches and family functionality. A cross-sectional study was conducted with 2021 secondary students to identify the prevalence of IA and to explore the association between adolescent IA and familial variables, including parents' marital status, family income, family conflict, family functionality, and parenting approaches. The results revealed that 25.3 % of the adolescent respondents exhibited IA, and logistic regression positively predicted the IA of adolescents from divorced families, low-income families, families in which family conflict existed, and severely dysfunctional families. Interestingly, adolescents with restricted Internet use were almost 1.9 times more likely to have IA than those whose use was not restricted. Internet addiction is common among Chinese adolescents in Hong Kong, and family-based prevention strategies should be aligned with the risk factors of IA.
-
NARX prediction of some rare chaotic flows: Recurrent fuzzy functions approach
Energy Technology Data Exchange (ETDEWEB)
Goudarzi, Sobhan [Biomedical Engineering Department, Amirkabir University of Technology, Tehran 15875-4413 (Iran, Islamic Republic of); Jafari, Sajad, E-mail: sajadjafari@aut.ac.ir [Biomedical Engineering Department, Amirkabir University of Technology, Tehran 15875-4413 (Iran, Islamic Republic of); Moradi, Mohammad Hassan [Biomedical Engineering Department, Amirkabir University of Technology, Tehran 15875-4413 (Iran, Islamic Republic of); Sprott, J.C. [Department of Physics, University of Wisconsin–Madison, Madison, WI 53706 (United States)
2016-02-15
The nonlinear and dynamic accommodating capability of time domain models makes them a useful representation of chaotic time series for analysis, modeling and prediction. This paper is devoted to the modeling and prediction of chaotic time series with hidden attractors using a nonlinear autoregressive model with exogenous inputs (NARX) based on a novel recurrent fuzzy functions (RFFs) approach. Case studies of recently introduced chaotic systems with hidden attractors plus classical chaotic systems demonstrate that the proposed modeling methodology exhibits better prediction performance from different viewpoints (short term and long term) compared to some other existing methods. - Highlights: • A new method is proposed for prediction of chaotic time series. • This method is based on novel recurrent fuzzy functions (RFFs) approach. • Some rare chaotic flows are used as test systems. • The new method shows proper performance in short-term prediction. • It also shows proper performance in prediction of attractor's topology.
-
[Suicidality and musical preferences: a possible link?].
Mikolajczak, Gladys; Desseilles, Martin
2012-01-01
Music is an important part of young people's lives. In this article, we attempt to answer two questions on the links between music et suicide. First, we examine if certain types of music favor suicidal process (ideation and acting out); and, secondly, we examine if music can constitute a tool to reduce the risk of suicide. Several factors possibly involved in links between musical preferences and the suicidal process are developed: the Velten effect and the musical mood induction procedure, the identification and the learning by imitation, the media influence as well as the individual characteristics. A multifactor approach is necessary to understand the complex and birectional links that unite musical preferences and suicide risk.
-
Lightweight link dimensioning using sFlow sampling
DEFF Research Database (Denmark)
de Oliviera Schmidt, Ricardo; Sadre, Ramin; Sperotto, Anna
2013-01-01
not be trivial in high-speed links. Aiming scalability, operators often deploy packet sampling on monitoring, but little is known how it affects link dimensioning. In this paper we assess the feasibility of lightweight link dimensioning using sFlow, which is a widely-deployed traffic monitoring tool. We...... implement sFlow sampling algorithm and use a previously proposed and validated dimensioning formula that needs traffic variance. We validate our approach using packet captures from real networks. Results show that the proposed procedure is successful for a range of sampling rates and that, due to randomness...... of sampling algorithm, the error introduced by scaling the traffic variance yields more conservative results that cope with short-term traffic fluctuations....
-
An Accurate Link Correlation Estimator for Improving Wireless Protocol Performance
Zhao, Zhiwei; Xu, Xianghua; Dong, Wei; Bu, Jiajun
2015-01-01
Wireless link correlation has shown significant impact on the performance of various sensor network protocols. Many works have been devoted to exploiting link correlation for protocol improvements. However, the effectiveness of these designs heavily relies on the accuracy of link correlation measurement. In this paper, we investigate state-of-the-art link correlation measurement and analyze the limitations of existing works. We then propose a novel lightweight and accurate link correlation estimation (LACE) approach based on the reasoning of link correlation formation. LACE combines both long-term and short-term link behaviors for link correlation estimation. We implement LACE as a stand-alone interface in TinyOS and incorporate it into both routing and flooding protocols. Simulation and testbed results show that LACE: (1) achieves more accurate and lightweight link correlation measurements than the state-of-the-art work; and (2) greatly improves the performance of protocols exploiting link correlation. PMID:25686314
-
Xie, Chunming; Ma, Lisha; Jiang, Nan; Huang, Ruyan; Li, Li; Gong, Liang; He, Cancan; Xiao, Chaoyong; Liu, Wen; Xu, Shu; Zhang, Zhijun
2017-08-01
Altered reward processing and cognitive deficits are often observed in patients with obsessive-compulsive disorder (OCD); however, whether the imbalance in activity between reward circuits and the cognitive control (CC) system is associated with compulsive behavior remains unknown. Sixty-eight OCD patients and 33 cognitively normal (CN) healthy subjects participated in this resting-state functional magnetic resonance imaging study. Alterations in the functional connectivity between reward circuits and the CC system were quantitatively assessed and compared between the groups. A Granger causality analysis was used to determine the causal informational influence between and within reward circuits and the CC system across all subjects. OCD patients showed a dichotomous pattern of enhanced functional coupling in their reward circuits and a weakened functional coupling in their CC system when compared to CN subjects. Neural correlates of compulsive behavior were primarily located in the reward circuits and CC system in OCD patients. Importantly, the CC system exerted a reduced interregional causal influence over the reward system in OCD patients relative to its effect in CN subjects. The limitations of this study are that it was a cross-sectional study and the potential effects of environmental and genetic factors were not explored. OCD patients showed an imbalance in the functional link between reward circuits and the CC system at rest. This bias toward a loss of control may define a pathological state in which subjects are more vulnerable to engaging in compulsive behaviors.
-
A new approach to stochastic transport via the functional Volterra expansion
International Nuclear Information System (INIS)
Ziya Akcasu, A.; Corngold, N.
2005-01-01
In this paper we present a new algorithm (FDA) for the calculation of the mean and the variance of the flux in stochastic transport when the transport equation contains a spatially random parameter θ(r), such as the density of the medium. The approach is based on the renormalized functional Volterra expansion of the flux around its mean. The attractive feature of the approach is that it explicitly displays the functional dependence of the flux on the products of θ(r i ), and hence enables one to take ensemble averages directly to calculate the moments of the flux in terms of the correlation functions of the underlying random process. The renormalized deterministic transport equation for the mean flux has been obtained to the second order in θ(r), and a functional relationship between the variance and the mean flux has been derived to calculate the variance to this order. The feasibility and accuracy of FDA has been demonstrated in the case of stochastic diffusion, using the diffusion equation with a spatially random diffusion coefficient. The connection of FDA with the well-established approximation schemes in the field of stochastic linear differential equations, such as the Bourret approximation, developed by Van Kampen using cumulant expansion, and by Terwiel using projection operator formalism, which has recently been extended to stochastic transport by Corngold. We hope that FDA's potential will be explored numerically in more realistic applications of the stochastic transport. (authors)
-
Simplifying the parallelization of scientific codes by a function-centric approach in Python
International Nuclear Information System (INIS)
Nilsen, Jon K; Cai Xing; Langtangen, Hans Petter; Hoeyland, Bjoern
2010-01-01
The purpose of this paper is to show how existing scientific software can be parallelized using a separate thin layer of Python code where all parallelization-specific tasks are implemented. We provide specific examples of such a Python code layer, which can act as templates for parallelizing a wide set of serial scientific codes. The use of Python for parallelization is motivated by the fact that the language is well suited for reusing existing serial codes programmed in other languages. The extreme flexibility of Python with regard to handling functions makes it very easy to wrap up decomposed computational tasks of a serial scientific application as Python functions. Many parallelization-specific components can be implemented as generic Python functions, which may take as input those wrapped functions that perform concrete computational tasks. The overall programming effort needed by this parallelization approach is limited, and the resulting parallel Python scripts have a compact and clean structure. The usefulness of the parallelization approach is exemplified by three different classes of application in natural and social sciences.
-
Hermite Functional Link Neural Network for Solving the Van der Pol-Duffing Oscillator Equation.
Mall, Susmita; Chakraverty, S
2016-08-01
Hermite polynomial-based functional link artificial neural network (FLANN) is proposed here to solve the Van der Pol-Duffing oscillator equation. A single-layer hermite neural network (HeNN) model is used, where a hidden layer is replaced by expansion block of input pattern using Hermite orthogonal polynomials. A feedforward neural network model with the unsupervised error backpropagation principle is used for modifying the network parameters and minimizing the computed error function. The Van der Pol-Duffing and Duffing oscillator equations may not be solved exactly. Here, approximate solutions of these types of equations have been obtained by applying the HeNN model for the first time. Three mathematical example problems and two real-life application problems of Van der Pol-Duffing oscillator equation, extracting the features of early mechanical failure signal and weak signal detection problems, are solved using the proposed HeNN method. HeNN approximate solutions have been compared with results obtained by the well known Runge-Kutta method. Computed results are depicted in term of graphs. After training the HeNN model, we may use it as a black box to get numerical results at any arbitrary point in the domain. Thus, the proposed HeNN method is efficient. The results reveal that this method is reliable and can be applied to other nonlinear problems too.
-
Protein O-linked ß-N-acetylglucosamine: A novel effector of cardiomyocyte metabolism and function
Darley-Usmar, Victor M.; Ball, Lauren E.; Chatham, John C.
2014-01-01
The post-translational modification of serine and threonine residues of nuclear and cytoplasmic proteins by the O-linked attachment of the monosaccharide ß-N-acetyl-glucosamine (O-GlcNAc) is emerging as an important mechanism for the regulation of numerous biological processes critical for normal cell function. Active synthesis of O-GlcNAc is essential for cell viability and acute activation of pathways resulting in increased protein O-GlcNAc levels improves the tolerance of cells to a wide range of stress stimuli. Conversely sustained increases in O-GlcNAc levels have been implicated in numerous chronic disease states, especially as a pathogenic contributor to diabetic complications. There has been increasing interest in the role of O-GlcNAc in the heart and vascular system and acute activation of O-GlcNAc levels have been shown to reduce ischemia/reperfusion injury attenuate vascular injury responses as well mediate some of the detrimental effects of diabetes and hypertension on cardiac and vascular function. Here we provide an overview of our current understanding of pathways regulating protein O-GlcNAcylation, summarize the different methodologies for identifying and characterizing O-GlcNAcylated proteins and subsequently focus on two emerging areas: 1) the role of O-GlcNAc as a potential regulator of cardiac metabolism and 2) the cross talk between O-GlcNAc and reactive oxygen species. PMID:21878340
-
A functional genomics approach using metabolomics and in silico pathway analysis
DEFF Research Database (Denmark)
Förster, Jochen; Gombert, Andreas Karoly; Nielsen, Jens
2002-01-01
analysis techniques and changes in the genotype will in many cases lead to different metabolite profiles. Here, a theoretical framework that may be applied to identify the function of orphan genes is presented. The approach is based on a combination of metabolome analysis combined with in silico pathway...
-
Zebrafish Functional Genetics Approach to the Pathogenesis of Well-Differentiated Liposarcoma
2015-12-01
Roderick JE, LaBelle JL, Bird G, Mathieu R, Bodaar K, Colon D, Pyati U, Stevenson KE, Qi J, Harris M, Silverman LB, Sallan SE, Bradner JL, Neuberg DS...pathogenesis of high-risk T-cell acute lymphoblastic leukemia. Our approach combines human cancer genomics with functional genetics, biochemistry and
-
A multifaceted approach to maximize erectile function and vascular health.
Meldrum, David R; Gambone, Joseph C; Morris, Marge A; Ignarro, Louis J
2010-12-01
To review the role of various factors influencing vascular nitric oxide (NO) and cyclic GMP, and consequently, erectile function and vascular health. Pertinent publications are reviewed. Daily moderate exercise stimulates vascular NO production. Maintenance of normal body weight and waist/hip ratio allows NO stimulation by insulin. Decreased intake of fat, sugar, and simple carbohydrates rapidly converted to sugar reduces the adverse effects of fatty acids and sugar on endothelial NO production. Omega-3 fatty acids stimulate endothelial NO release. Antioxidants boost NO production and prevent NO breakdown. Folic acid, calcium, vitamin C, and vitamin E support the biochemical pathways leading to NO release. Cessation of smoking and avoidance of excessive alcohol preserve normal endothelial function. Moderate use of alcohol and certain proprietary supplements may favorably influence erectile and vascular function. Treatment of any remaining testosterone deficit will both increase erectile function and reduce any associated metabolic syndrome. After production of NO and cyclic GMP are improved, use of phosphodiesterase-5 inhibitors should result in greater success in treating remaining erectile dysfunction. Recent studies have also suggested positive effects of phosphodiesterase-5 inhibitors on vascular function. A multifaceted approach will maximize both erectile function and vascular health. Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
-
Radi, Marjan; Dezfouli, Behnam; Abu Bakar, Kamalrulnizam; Abd Razak, Shukor
2014-01-01
Network connectivity and link quality information are the fundamental requirements of wireless sensor network protocols to perform their desired functionality. Most of the existing discovery protocols have only focused on the neighbor discovery problem, while a few number of them provide an integrated neighbor search and link estimation. As these protocols require a careful parameter adjustment before network deployment, they cannot provide scalable and accurate network initialization in large-scale dense wireless sensor networks with random topology. Furthermore, performance of these protocols has not entirely been evaluated yet. In this paper, we perform a comprehensive simulation study on the efficiency of employing adaptive protocols compared to the existing nonadaptive protocols for initializing sensor networks with random topology. In this regard, we propose adaptive network initialization protocols which integrate the initial neighbor discovery with link quality estimation process to initialize large-scale dense wireless sensor networks without requiring any parameter adjustment before network deployment. To the best of our knowledge, this work is the first attempt to provide a detailed simulation study on the performance of integrated neighbor discovery and link quality estimation protocols for initializing sensor networks. This study can help system designers to determine the most appropriate approach for different applications.
-
Directory of Open Access Journals (Sweden)
Marjan Radi
2014-01-01
Full Text Available Network connectivity and link quality information are the fundamental requirements of wireless sensor network protocols to perform their desired functionality. Most of the existing discovery protocols have only focused on the neighbor discovery problem, while a few number of them provide an integrated neighbor search and link estimation. As these protocols require a careful parameter adjustment before network deployment, they cannot provide scalable and accurate network initialization in large-scale dense wireless sensor networks with random topology. Furthermore, performance of these protocols has not entirely been evaluated yet. In this paper, we perform a comprehensive simulation study on the efficiency of employing adaptive protocols compared to the existing nonadaptive protocols for initializing sensor networks with random topology. In this regard, we propose adaptive network initialization protocols which integrate the initial neighbor discovery with link quality estimation process to initialize large-scale dense wireless sensor networks without requiring any parameter adjustment before network deployment. To the best of our knowledge, this work is the first attempt to provide a detailed simulation study on the performance of integrated neighbor discovery and link quality estimation protocols for initializing sensor networks. This study can help system designers to determine the most appropriate approach for different applications.
-
Link Prediction in Evolving Networks Based on Popularity of Nodes.
Wang, Tong; He, Xing-Sheng; Zhou, Ming-Yang; Fu, Zhong-Qian
2017-08-02
Link prediction aims to uncover the underlying relationship behind networks, which could be utilized to predict missing edges or identify the spurious edges. The key issue of link prediction is to estimate the likelihood of potential links in networks. Most classical static-structure based methods ignore the temporal aspects of networks, limited by the time-varying features, such approaches perform poorly in evolving networks. In this paper, we propose a hypothesis that the ability of each node to attract links depends not only on its structural importance, but also on its current popularity (activeness), since active nodes have much more probability to attract future links. Then a novel approach named popularity based structural perturbation method (PBSPM) and its fast algorithm are proposed to characterize the likelihood of an edge from both existing connectivity structure and current popularity of its two endpoints. Experiments on six evolving networks show that the proposed methods outperform state-of-the-art methods in accuracy and robustness. Besides, visual results and statistical analysis reveal that the proposed methods are inclined to predict future edges between active nodes, rather than edges between inactive nodes.
-
Functional imaging in oncology. Biophysical basis and technical approaches. Vol. 1
Energy Technology Data Exchange (ETDEWEB)
Luna, Antonio [Health Time Group, Jaen (Spain); University Hospitals, Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Radiology; Vilanova, Joan C. [Clinica Girona - Hospital Sta. Caterina, Girona (Spain); Hygino da Cruz, L. Celso Jr. [CDPI and IRM, Rio de Janeiro, RJ (Brazil). Dept. of Radiology; Rossi, Santiago E. (ed.) [Centro de Diagnostico, Buenos Aires (Argentina)
2014-07-01
Easy-to-read manual on new functional imaging techniques in oncology. Explains current clinical applications and outlines future avenues. Includes numerous high-quality illustrations to highlight the major teaching points. In the new era of functional and molecular imaging, both currently available imaging biomarkers and biomarkers under development are expected to lead to major changes in the management of oncological patients. This well-illustrated two-volume book is a practical manual on the various imaging techniques capable of delivering functional information on cancer, including preclinical and clinical imaging techniques, based on US, CT, MRI, PET and hybrid modalities. This first volume explains the biophysical basis for these functional imaging techniques and describes the techniques themselves. Detailed information is provided on the imaging of cancer hallmarks, including angiogenesis, tumor metabolism, and hypoxia. The techniques and their roles are then discussed individually, covering the full range of modalities in clinical use as well as new molecular and functional techniques. The value of a multiparametric approach is also carefully considered.
-
Functional imaging in oncology. Biophysical basis and technical approaches. Vol. 1
International Nuclear Information System (INIS)
Luna, Antonio; Hygino da Cruz, L. Celso Jr.
2014-01-01
Easy-to-read manual on new functional imaging techniques in oncology. Explains current clinical applications and outlines future avenues. Includes numerous high-quality illustrations to highlight the major teaching points. In the new era of functional and molecular imaging, both currently available imaging biomarkers and biomarkers under development are expected to lead to major changes in the management of oncological patients. This well-illustrated two-volume book is a practical manual on the various imaging techniques capable of delivering functional information on cancer, including preclinical and clinical imaging techniques, based on US, CT, MRI, PET and hybrid modalities. This first volume explains the biophysical basis for these functional imaging techniques and describes the techniques themselves. Detailed information is provided on the imaging of cancer hallmarks, including angiogenesis, tumor metabolism, and hypoxia. The techniques and their roles are then discussed individually, covering the full range of modalities in clinical use as well as new molecular and functional techniques. The value of a multiparametric approach is also carefully considered.
-
Kong, Xiangzhen; He, Wei; Liu, Wenxiu; Yang, Bin; Xu, Fuliu; Jørgensen, Sven Erik; Mooij, W.M.
2016-01-01
Food web structure dynamics and ecosystem functioning are strongly linked, and both are indispensable in evaluating ecosystem development in lakes under multiple anthropogenic stressors. However, model-based approaches concerning the changes in food web structure and ecosystem functioning in a
-
Named Entity Linking Algorithm
Directory of Open Access Journals (Sweden)
M. F. Panteleev
2017-01-01
Full Text Available In the tasks of processing text in natural language, Named Entity Linking (NEL represents the task to define and link some entity, which is found in the text, with some entity in the knowledge base (for example, Dbpedia. Currently, there is a diversity of approaches to solve this problem, but two main classes can be identified: graph-based approaches and machine learning-based ones. Graph and Machine Learning approaches-based algorithm is proposed accordingly to the stated assumptions about the interrelations of named entities in a sentence and in general.In the case of graph-based approaches, it is necessary to solve the problem of identifying an optimal set of the related entities according to some metric that characterizes the distance between these entities in a graph built on some knowledge base. Due to limitations in processing power, to solve this task directly is impossible. Therefore, its modification is proposed. Based on the algorithms of machine learning, an independent solution cannot be built due to small volumes of training datasets relevant to NEL task. However, their use can contribute to improving the quality of the algorithm. The adaptation of the Latent Dirichlet Allocation model is proposed in order to obtain a measure of the compatibility of attributes of various entities encountered in one context.The efficiency of the proposed algorithm was experimentally tested. A test dataset was independently generated. On its basis the performance of the model was compared using the proposed algorithm with the open source product DBpedia Spotlight, which solves the NEL problem.The mockup, based on the proposed algorithm, showed a low speed as compared to DBpedia Spotlight. However, the fact that it has shown higher accuracy, stipulates the prospects for work in this direction.The main directions of development were proposed in order to increase the accuracy of the system and its productivity.
-
A zeta function approach to the semiclassical quantization of maps
International Nuclear Information System (INIS)
Smilansky, Uzi.
1993-11-01
The quantum analogue of an area preserving map on a compact phase space is a unitary (evolution) operator which can be represented by a matrix of dimension L∝ℎ -1 . The semiclassical theory for spectrum of the evolution operator will be reviewed with special emphasize on developing a dynamical zeta function approach, similar to the one introduced recently for a semiclassical quantization of hamiltonian systems. (author)
-
Pfleger, Christopher; Rathi, Prakash Chandra; Klein, Doris L; Radestock, Sebastian; Gohlke, Holger
2013-04-22
For deriving maximal advantage from information on biomacromolecular flexibility and rigidity, results from rigidity analyses must be linked to biologically relevant characteristics of a structure. Here, we describe the Python-based software package Constraint Network Analysis (CNA) developed for this task. CNA functions as a front- and backend to the graph-based rigidity analysis software FIRST. CNA goes beyond the mere identification of flexible and rigid regions in a biomacromolecule in that it (I) provides a refined modeling of thermal unfolding simulations that also considers the temperature-dependence of hydrophobic tethers, (II) allows performing rigidity analyses on ensembles of network topologies, either generated from structural ensembles or by using the concept of fuzzy noncovalent constraints, and (III) computes a set of global and local indices for quantifying biomacromolecular stability. This leads to more robust results from rigidity analyses and extends the application domain of rigidity analyses in that phase transition points ("melting points") and unfolding nuclei ("structural weak spots") are determined automatically. Furthermore, CNA robustly handles small-molecule ligands in general. Such advancements are important for applying rigidity analysis to data-driven protein engineering and for estimating the influence of ligand molecules on biomacromolecular stability. CNA maintains the efficiency of FIRST such that the analysis of a single protein structure takes a few seconds for systems of several hundred residues on a single core. These features make CNA an interesting tool for linking biomacromolecular structure, flexibility, (thermo-)stability, and function. CNA is available from http://cpclab.uni-duesseldorf.de/software for nonprofit organizations.
-
Decentralising Curriculum Reform: The Link Teacher Model of In-Service Training.
Wildy, Helen; And Others
1996-01-01
Presents a (Western Australian) case study of the link teacher model, a decentralized, "train the trainer" approach to inservice education. Discusses the model's perceived effectiveness, the link teachers' role, central authority support, and new experimentation opportunities. Combining centralized syllabus change with decentralized…
-
Kashuba, Roxolana; McMahon, Gerard; Cuffney, Thomas F.; Qian, Song; Reckhow, Kenneth; Gerritsen, Jeroen; Davies, Susan
2012-01-01
Urban development alters important physical, chemical, and biological processes that define urban stream ecosystems. An approach was developed for quantifying the effects of these processes on aquatic biota, and then linking those effects to endpoints that can be used for environmental management. These complex, interacting systems are challenging to model from a scientific standpoint. A desirable model clearly shows the system, simulates the interactions, and ultimately predicts results of management actions. Traditional regression techniques that calculate empirical relations between pairs of environmental factors do not capture the interconnected web of multiple stressors, but urban development effects are not yet understood at the detailed scales required to make mechanistic modeling approaches feasible. Therefore, in contrast to a fully deterministic or fully statistical modeling approach, a Bayesian network model provides a hybrid approach that can be used to represent known general associations between variables while acknowledging uncertainty in predicted outcomes. It does so by quantifying an expert-elicited network of probabilistic relations between variables. Advantages of this modeling approach include (1) flexibility in accommodating many model specifications and information types; (2) efficiency in storing and manipulating complex information, and to parameterize; and (3) transparency in describing the relations using nodes and arrows and in describing uncertainties with discrete probability distributions for each variable.
-
Institute of Scientific and Technical Information of China (English)
Liang Kou; Hongkun He; Chao Gao
2010-01-01
A facile 'click chemistry' approach to functionalize 2D macromolecules of graphene oxide nanosheets with poly(ethylene glycol) of different molecular weights,polystyrene,palmitic acid and various amino acids was presented.FTIR,TGA,Raman spectroscopy,XPS,XRD,TEM,AFM and SEM were utilized to characterize the products.High degree of functionalization was achieved on the flat surfaces of graphene oxide,affording polymer-grafted 2D brushes and amino acids-immobilized nanosheets,which show improved solubility in organic solvents.The click chemistry strategy reported herein provides a facile and general method for functionalization of graphene oxide with macromolecules and desired biomolecules.
-
Wetting transitions: A functional renormalization-group approach
International Nuclear Information System (INIS)
Fisher, D.S.; Huse, D.A.
1985-01-01
A linear functional renormalization group is introduced as a framework in which to treat various wetting transitions of films on substrates. A unified treatment of the wetting transition in three dimensions with short-range interactions is given. The results of Brezin, Halperin, and Leibler in their three different regimes are reproduced along with new results on the multicritical behavior connecting the various regimes. In addition, the critical behavior as the coexistence curve is approached at complete wetting is analyzed. Wetting in the presence of long-range substrate-film interactions that fall off as power laws is also studied. The possible effects of the nonlinear terms in the renormalization group are examined briefly and it appears that they do not alter the critical behavior found using the truncated linear renormalization group
-
The Use of Modeling Approach for Teaching Exponential Functions
Nunes, L. F.; Prates, D. B.; da Silva, J. M.
2017-12-01
This work presents a discussion related to the teaching and learning of mathematical contents related to the study of exponential functions in a freshman students group enrolled in the first semester of the Science and Technology Bachelor’s (STB of the Federal University of Jequitinhonha and Mucuri Valleys (UFVJM). As a contextualization tool strongly mentioned in the literature, the modelling approach was used as an educational teaching tool to produce contextualization in the teaching-learning process of exponential functions to these students. In this sense, were used some simple models elaborated with the GeoGebra software and, to have a qualitative evaluation of the investigation and the results, was used Didactic Engineering as a methodology research. As a consequence of this detailed research, some interesting details about the teaching and learning process were observed, discussed and described.
-
Linking vegetation structure, function and physiology through spectroscopic remote sensing
Serbin, S.; Singh, A.; Couture, J. J.; Shiklomanov, A. N.; Rogers, A.; Desai, A. R.; Kruger, E. L.; Townsend, P. A.
2015-12-01
Terrestrial ecosystem process models require detailed information on ecosystem states and canopy properties to properly simulate the fluxes of carbon (C), water and energy from the land to the atmosphere and assess the vulnerability of ecosystems to perturbations. Current models fail to adequately capture the magnitude, spatial variation, and seasonality of terrestrial C uptake and storage, leading to significant uncertainties in the size and fate of the terrestrial C sink. By and large, these parameter and process uncertainties arise from inadequate spatial and temporal representation of plant traits, vegetation structure, and functioning. With increases in computational power and changes to model architecture and approaches, it is now possible for models to leverage detailed, data rich and spatially explicit descriptions of ecosystems to inform parameter distributions and trait tradeoffs. In this regard, spectroscopy and imaging spectroscopy data have been shown to be invaluable observational datasets to capture broad-scale spatial and, eventually, temporal dynamics in important vegetation properties. We illustrate the linkage of plant traits and spectral observations to supply key data constraints for model parameterization. These constraints can come either in the form of the raw spectroscopic data (reflectance, absorbtance) or physiological traits derived from spectroscopy. In this presentation we highlight our ongoing work to build ecological scaling relationships between critical vegetation characteristics and optical properties across diverse and complex canopies, including temperate broadleaf and conifer forests, Mediterranean vegetation, Arctic systems, and agriculture. We focus on work at the leaf, stand, and landscape scales, illustrating the importance of capturing the underlying variability in a range of parameters (including vertical variation within canopies) to enable more efficient scaling of traits related to functional diversity of ecosystems.
-
Density functional approach for the magnetism of β-TeVO4
Saúl, A.; Radtke, G.
2014-03-01
Density functional calculations have been carried out to investigate the microscopic origin of the magnetic properties of β-TeVO4. Two different approaches, based either on a perturbative treatment of the multiorbital Hubbard model in the strongly correlated limit or on the calculation of supercell total energy differences, have been employed to evaluate magnetic couplings in this compound. The picture provided by these two approaches is that of weakly coupled frustrated chains with ferromagnetic nearest-neighbor and antiferromagnetic second-nearest-neighbor couplings. These results, differing substantially from previous reports, should motivate further experimental investigations of the magnetic properties of this compound.
-
de Jong, Luitzen; de Koning, Edward A; Roseboom, Winfried; Buncherd, Hansuk; Wanner, Martin J; Dapic, Irena; Jansen, Petra J; van Maarseveen, Jan H; Corthals, Garry L; Lewis, Peter J; Hamoen, Leendert W; de Koster, Chris G
2017-07-07
Identification of dynamic protein-protein interactions at the peptide level on a proteomic scale is a challenging approach that is still in its infancy. We have developed a system to cross-link cells directly in culture with the special lysine cross-linker bis(succinimidyl)-3-azidomethyl-glutarate (BAMG). We used the Gram-positive model bacterium Bacillus subtilis as an exemplar system. Within 5 min extensive intracellular cross-linking was detected, while intracellular cross-linking in a Gram-negative species, Escherichia coli, was still undetectable after 30 min, in agreement with the low permeability in this organism for lipophilic compounds like BAMG. We were able to identify 82 unique interprotein cross-linked peptides with cross-links occur in assemblies involved in transcription and translation. Several of these interactions are new, and we identified a binding site between the δ and β' subunit of RNA polymerase close to the downstream DNA channel, providing a clue into how δ might regulate promoter selectivity and promote RNA polymerase recycling. Our methodology opens new avenues to investigate the functional dynamic organization of complex protein assemblies involved in bacterial growth. Data are available via ProteomeXchange with identifier PXD006287.
-
Charususin, Noppawan; Dacha, Sauwaluk; Gosselink, Rik; Decramer, Marc; Von Leupoldt, Andreas; Reijnders, Thomas; Louvaris, Zafeiris; Langer, Daniel
2018-01-01
Respiratory muscle dysfunction is common and contributes to dyspnea and exercise limitation in patients with chronic obstructive pulmonary disease (COPD). Improving dynamic function of respiratory muscles during exercise might help to reduce symptoms and improve exercise capacity. Areas covered: The aims of this review are to 1) summarize physiological mechanisms linking respiratory muscle dysfunction to dyspnea and exercise limitation; 2) provide an overview of available therapeutic approaches to better maintain load-capacity balance of respiratory muscles during exercise; and 3) to summarize current knowledge on potential mechanisms explaining effects of interventions aimed at optimizing dynamic respiratory muscle function with a special focus on inspiratory muscle training. Expert commentary: Several mechanisms which are potentially linking improvements in dynamic respiratory muscle function to symptomatic and functional benefits have not been studied so far in COPD patients. Examples of underexplored areas include the study of neural processes related to the relief of acute dyspnea and the competition between respiratory and peripheral muscles for limited energy supplies during exercise. Novel methodologies are available to non-invasively study these mechanisms. Better insights into the consequences of dynamic respiratory muscle dysfunction will hopefully contribute to further refine and individualize therapeutic approaches in patients with COPD.
-
Functional Genomics Approaches to Studying Symbioses between Legumes and Nitrogen-Fixing Rhizobia.
Lardi, Martina; Pessi, Gabriella
2018-05-18
Biological nitrogen fixation gives legumes a pronounced growth advantage in nitrogen-deprived soils and is of considerable ecological and economic interest. In exchange for reduced atmospheric nitrogen, typically given to the plant in the form of amides or ureides, the legume provides nitrogen-fixing rhizobia with nutrients and highly specialised root structures called nodules. To elucidate the molecular basis underlying physiological adaptations on a genome-wide scale, functional genomics approaches, such as transcriptomics, proteomics, and metabolomics, have been used. This review presents an overview of the different functional genomics approaches that have been performed on rhizobial symbiosis, with a focus on studies investigating the molecular mechanisms used by the bacterial partner to interact with the legume. While rhizobia belonging to the alpha-proteobacterial group (alpha-rhizobia) have been well studied, few studies to date have investigated this process in beta-proteobacteria (beta-rhizobia).
-
de Carvalho, Marcelo Pires Nogueira; Queiroz-Hazarbassanov, Nicolle Gilda Teixeira; de Oliveira Massoco, Cristina; Sant'Anna, Sávio Stefanini; Lourenço, Mariana Mathias; Levin, Gabriel; Sogayar, Mari Cleide; Grego, Kathleen Fernandes; Catão-Dias, José Luiz
2017-09-01
Reptiles are the unique ectothermic amniotes, providing the key link between ectothermic anamniotes fish and amphibians, and endothermic birds and mammals; becoming an important group to study with the aim of providing significant knowledge into the evolutionary history of vertebrate immunity. Classification systems for reptiles' leukocytes have been described by their appearance rather than function, being still inconsistent. With the advent of modern techniques and the establishment of analytical protocols for snakes' blood by flow cytometry, we bring a qualitative and quantitative assessment of innate activities presented by snakes' peripheral blood leukocytes, thereby linking flow cytometric features with fluorescent and light microscopy images. Moreover, since corticosterone is an important immunomodulator in reptiles, hormone levels of all blood samples were measured. We provide novel and additional information which should contribute to better understanding of the development of the immune system of reptiles and vertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.
-
Bozzini, Sabrina; Giuliano, Liliana; Altomare, Lina; Petrini, Paola; Bandiera, Antonella; Conconi, Maria Teresa; Farè, Silvia; Tanzi, Maria Cristina
2011-12-01
The use of polymers naturally occurring in the extracellular matrix (ECM) is a promising strategy in regenerative medicine. If compared to natural ECM proteins, proteins obtained by recombinant DNA technology have intrinsic advantages including reproducible macromolecular composition, sequence and molecular mass, and overcoming the potential pathogens transmission related to polymers of animal origin. Among ECM-mimicking materials, the family of recombinant elastin-like polymers is proposed for drug delivery applications and for the repair of damaged elastic tissues. This work aims to evaluate the potentiality of a recombinant human elastin-like polypeptide (HELP) as a base material of cross-linked matrices for regenerative medicine. The cross-linking of HELP was accomplished by the insertion of cross-linking sites, glutamine and lysine, in the recombinant polymer and generating ε-(γ-glutamyl) lysine links through the enzyme transglutaminase. The cross-linking efficacy was estimated by infrared spectroscopy. Freeze-dried cross-linked matrices showed swelling ratios in deionized water (≈2500%) with good structural stability up to 24 h. Mechanical compression tests, performed at 37°C in wet conditions, in a frequency sweep mode, indicated a storage modulus of 2/3 kPa, with no significant changes when increasing number of cycles or frequency. These results demonstrate the possibility to obtain mechanically resistant hydrogels via enzymatic crosslinking of HELP. Cytotoxicity tests of cross-linked HELP were performed with human umbilical vein endothelial cells, by use of transwell filter chambers for 1-7 days, or with its extracts in the opportune culture medium for 24 h. In both cases no cytotoxic effects were observed in comparison with the control cultures. On the whole, the results suggest the potentiality of this genetically engineered HELP for regenerative medicine applications, particularly for vascular tissue regeneration.
-
Directory of Open Access Journals (Sweden)
Cova Matteo
2014-06-01
Full Text Available Fatigue strength is known to decrease with increasing dimension of the component. This is due to a technological size effect, related to the production process, and to a geometrical size effect, due to a higher probability of finding a large defect. To investigate the latter, an heavy-walled component made of Ductile Cast Iron (DCI has been trepanned and a fatigue test plan has been carried out using 4 different specimen geometries. An attempt has been made to relate the resulting fatigue strength using a weakest-link approach based on the effective volumes and surfaces. This approach seems to work well only in cases of different specimen's lengths. Some of the fracture surfaces were analyzed by means of SEM and the initiating defects were identified and measured. An approach in which the defects population can be randomly distributed in the specimen has been tried. Virtual fatigue tests have been carried out by considering pure propagation of the worst defect. The resulting fatigue curves showed that this approach is promising but needs further description of the initiation phase.
-
The Algorithm of Link Prediction on Social Network
Directory of Open Access Journals (Sweden)
Liyan Dong
2013-01-01
Full Text Available At present, most link prediction algorithms are based on the similarity between two entities. Social network topology information is one of the main sources to design the similarity function between entities. But the existing link prediction algorithms do not apply the network topology information sufficiently. For lack of traditional link prediction algorithms, we propose two improved algorithms: CNGF algorithm based on local information and KatzGF algorithm based on global information network. For the defect of the stationary of social network, we also provide the link prediction algorithm based on nodes multiple attributes information. Finally, we verified these algorithms on DBLP data set, and the experimental results show that the performance of the improved algorithm is superior to that of the traditional link prediction algorithm.
-
DEFF Research Database (Denmark)
Dehlholm-Lambertsen, Birgitte; Hulgaard, Ditte Roth
-established collaboration with the Pediatric department, University Hospital of Southern Denmark. The treatment is based on a biopsychosocial understanding combined with family therapy with elements of systemic and narrative theories. Objective: • Presentation of the family therapy approach used in the department of Child...... and Adolescent Psychiatry, University Hospital of Southern Denmark. • Discussion of different approaches to family therapy for adolescents with functional somatic symptoms • Discussion of challenges and advantages of a systemic narrative approach to families of adolescents with functional somatic symptoms....... evidence on the effect of psychological treatment. At the department of Child and Adolescent Psychiatry, University Hospital of Southern Denmark, a team of experienced therapists has developed an approach for the treatment of adolescents with FSS. This approach includes a formalized and well...
-
A Goal-Function Approach to Analysis of Control Situations
DEFF Research Database (Denmark)
Lind, Morten
2010-01-01
The concept of situations plays a central role in all theories of meaning and context. and serve to frame or group events and other occurrences into coherent meaningful wholes. Situations are typed, may be interconnected and organized into higher level structures. In operation of industrial...... processes situations should identify operational aspects relevant for control agent’s decision making in plant supervision and control. Control situations can be understood as recurrent and interconnected patterns of control with important implications for control and HMI design. Goal-Function approaches...
-
Directory of Open Access Journals (Sweden)
Michael L. Kasusse
2015-11-01
Full Text Available Background: Improving laboratory service delivery requires a functioning logistics and supply system. Uganda’s Ministry of Health uses the credit-line approach to provide laboratory supplies including commodities for CD4 test equipment. Objectives: We examined the effectiveness of the credit-line approach in improving laboratoryservice delivery by using the functionality of CD4 test equipment as a proxy indicator. Method: A cross-sectional survey was conducted at 7 level-three health centres (HC IIIs, 18 level-four health centres (HC IVs, and 10 hospitals in 15 districts of mid-northern Uganda, including the Lango (17 facilities and Acholi sub-regions (18 facilities, between July 2013 and August 2013. Functionality, was determined through self- and interviewer-administered questionnaires. The chi-squared test was used to assess differences in functionality by subregion, facility type, and equipment type. Results: A total of 38 CD4 test analysers were assessed. Of these, 26 (68% were functional. In hospitals, 85% of CD4 analysers were functional, in HC IVs, 67% were functional and in HCIIIs, 43% were functional. The differences did not reach statistical significance. In the Langosub-region, 72% of analysers were functional; in the Acholi sub-region, 65% were functional. Non-functionality was mainly due to lack of reagents and cartridges, as well as low staffing levels of laboratory technicians with the skills necessary to operate the equipment. Conclusion: The credit-line approach supported the functionality of CD4 equipment in the surveyed facilities. However, there is a need to address issues of staffing and availability of reagents to enhance the functionality of CD4 equipment and improve patient care, especiallyat HC IIIs.
-
García-Palacios, Pablo; Vandegehuchte, Martijn L; Shaw, E Ashley; Dam, Marie; Post, Keith H; Ramirez, Kelly S; Sylvain, Zachary A; de Tomasel, Cecilia Milano; Wall, Diana H
2015-04-01
In recent years, there has been an increase in research to understand how global changes' impacts on soil biota translate into altered ecosystem functioning. However, results vary between global change effects, soil taxa, and ecosystem processes studied, and a synthesis of relationships is lacking. Therefore, here we initiate such a synthesis to assess whether the effect size of global change drivers (elevated CO2, N deposition, and warming) on soil microbial abundance is related with the effect size of these drivers on ecosystem functioning (plant biomass, soil C cycle, and soil N cycle) using meta-analysis and structural equation modeling. For N deposition and warming, the global change effect size on soil microbes was positively associated with the global change effect size on ecosystem functioning, and these relationships were consistent across taxa and ecosystem processes. However, for elevated CO2, such links were more taxon and ecosystem process specific. For example, fungal abundance responses to elevated CO2 were positively correlated with those of plant biomass but negatively with those of the N cycle. Our results go beyond previous assessments of the sensitivity of soil microbes and ecosystem processes to global change, and demonstrate the existence of general links between the responses of soil microbial abundance and ecosystem functioning. Further we identify critical areas for future research, specifically altered precipitation, soil fauna, soil community composition, and litter decomposition, that are need to better quantify the ecosystem consequences of global change impacts on soil biodiversity. © 2014 John Wiley & Sons Ltd.
-
Schwarz, Adam J; Gozzi, Alessandro; Bifone, Angelo
2009-08-01
In the study of functional connectivity, fMRI data can be represented mathematically as a network of nodes and links, where image voxels represent the nodes and the connections between them reflect a degree of correlation or similarity in their response. Here we show that, within this framework, functional imaging data can be partitioned into 'communities' of tightly interconnected voxels corresponding to maximum modularity within the overall network. We evaluated this approach systematically in application to networks constructed from pharmacological MRI (phMRI) of the rat brain in response to acute challenge with three different compounds with distinct mechanisms of action (d-amphetamine, fluoxetine, and nicotine) as well as vehicle (physiological saline). This approach resulted in bilaterally symmetric sub-networks corresponding to meaningful anatomical and functional connectivity pathways consistent with the purported mechanism of action of each drug. Interestingly, common features across all three networks revealed two groups of tightly coupled brain structures that responded as functional units independent of the specific neurotransmitter systems stimulated by the drug challenge, including a network involving the prefrontal cortex and sub-cortical regions extending from the striatum to the amygdala. This finding suggests that each of these networks includes general underlying features of the functional organization of the rat brain.
-
Link Label Prediction in Signed Citation Network
Akujuobi, Uchenna Thankgod
2016-01-01
such as using regression, trust propagation and matrix factorization. These approaches have tried to solve the problem of link label prediction by using ideas from social theories, where most of them predict a single missing label given that labels of other
-
Assessing Cognitive Function in Older Adults Using a Videoconference Approach
Teresa Costa Castanho; Liliana Amorim; Pedro Silva Moreira; José Mariz; Joana Almeida Palha; Nuno Sousa; Nadine Correia Santos
2016-01-01
Background: The use of communication technologies is an emerging trend in healthcare and research. Despite efficient, reliable and accurate neuropsychological batteries to evaluate cognitive performance in-person, more diverse and less expensive and time consuming solutions are needed. Here we conducted a pilot study to determine the applicability of a videoconference (VC, Skype (R)) approach to assess cognitive function in older adults, using The Telephone Interview for Cognitive Status-Modi...
-
Spiraling in Urban Streams: A Novel Approach to Link Geomorphic Structure with Ecosystem Function
Bean, R. A.; Lafrenz, M. D.
2011-12-01
The goal of this study is to quantify the relationship between channel complexity and nutrient spiraling along several reaches of an urbanized watershed in Portland, Oregon. Much research points to the effect urbanization has on watershed hydrology and nutrient loading at the watershed scale for various sized catchments. However the flux of nutrients over short reaches within a stream channel has been less studied because of the effort and costs associated with fieldwork and subsequent laboratory analysis of both surface and hyporheic water samples. In this study we explore a novel approach at capturing connectivity though nutrient spiraling along several short reaches (less than 100-meter) within the highly urbanized Fanno Creek watershed (4400 hectares). We measure channel complexity-sinuosity, bed material texture, organic matter-and use these measurements to determine spatial autocorrelation of 50 reaches in Fanno Creek, a small, urban watershed in Portland, Oregon. Using ion-selective electrodes, the fluxes of nitrate and ammonia are measured within each reach, which when combined with channel geometry and velocity measurements allow us to transform the values of nitrate and ammonia fluxes into spiraling metrics. Along each sampled reach, we collected three surface water samples to characterize nutrient amounts at the upstream, midstream, and downstream position of the reach. Two additional water samples were taken from the left and right bank hyporheic zones at a depth just below the armor layer of the channel bed using mini-piezometers and a hand-pumped vacuum device, which we constructed for this purpose. Adjacent to the hyporheic samples soil cores were collected and analyzed for organic matter composition, bulk density, and texture. We hypothesize that spiral metrics will respond significantly to the measured channel complexity values and will be a more robust predictor of nutrient flux than land cover characteristics in the area draining to each reach
-
Lerch, Mathias; Spoerri, Adrian; Jasilionis, Domantas; Viciana Fernandèz, Francisco
2017-07-14
Reliable estimates of mortality according to socioeconomic status play a crucial role in informing the policy debate about social inequality, social cohesion, and exclusion as well as about the reform of pension systems. Linked mortality data have become a gold standard for monitoring socioeconomic differentials in survival. Several approaches have been proposed to assess the quality of the linkage, in order to avoid the misclassification of deaths according to socioeconomic status. However, the plausibility of mortality estimates has never been scrutinized from a demographic perspective, and the potential problems with the quality of the data on the at-risk populations have been overlooked. Using indirect demographic estimation (i.e., the synthetic extinct generation method), we analyze the plausibility of old-age mortality estimates according to educational attainment in four European data contexts with different quality issues: deterministic and probabilistic linkage of deaths, as well as differences in the methodology of the collection of educational data. We evaluate whether the at-risk population according to educational attainment is misclassified and/or misestimated, correct these biases, and estimate the education-specific linkage rates of deaths. The results confirm a good linkage of death records within different educational strata, even when probabilistic matching is used. The main biases in mortality estimates concern the classification and estimation of the person-years of exposure according to educational attainment. Changes in the census questions about educational attainment led to inconsistent information over time, which misclassified the at-risk population. Sample censuses also misestimated the at-risk populations according to educational attainment. The synthetic extinct generation method can be recommended for quality assessments of linked data because it is capable not only of quantifying linkage precision, but also of tracking problems in
-
Performance of local information-based link prediction: a sampling perspective
Zhao, Jichang; Feng, Xu; Dong, Li; Liang, Xiao; Xu, Ke
2012-08-01
Link prediction is pervasively employed to uncover the missing links in the snapshots of real-world networks, which are usually obtained through different kinds of sampling methods. In the previous literature, in order to evaluate the performance of the prediction, known edges in the sampled snapshot are divided into the training set and the probe set randomly, without considering the underlying sampling approaches. However, different sampling methods might lead to different missing links, especially for the biased ways. For this reason, random partition-based evaluation of performance is no longer convincing if we take the sampling method into account. In this paper, we try to re-evaluate the performance of local information-based link predictions through sampling method governed division of the training set and the probe set. It is interesting that we find that for different sampling methods, each prediction approach performs unevenly. Moreover, most of these predictions perform weakly when the sampling method is biased, which indicates that the performance of these methods might have been overestimated in the prior works.
-
Tracing where and who provenance in Linked Data: A calculus
Dezani-Ciancaglini, Mariangiola; Horne, Ross; Sassone, Vladimiro
2012-01-01
Linked Data provides some sensible guidelines for publishing and consuming data on the Web. Data published on the Web has no inherent truth, yet its quality can often be assessed based on its provenance. This work introduces a new approach to provenance for Linked Data. The simplest notion of provenance-viz., a named graph indicating where the data is now-is extended with a richer provenance format. The format reflects the behaviour of processes interacting with Linked Data, tracing where the...
-
Linked data querying through FCA-based schema indexing
Brosius, Dominik; Staab, Steffen
2016-01-01
The effciency of SPARQL query evaluation against Linked Open Data may benefit from schema-based indexing. However, many data items come with incomplete schema information or lack schema descriptions entirely. In this position paper, we outline an approach to an indexing of linked data graphs based on schemata induced through Formal Concept Analysis. We show how to map queries onto RDF graphs based on such derived schema information. We sketch next steps for realizing and optimizing the sugges...
-
Leveraging Crowdsourcing and Linked Open Data for Geoscience Data Sharing and Discovery
Narock, T. W.; Rozell, E. A.; Hitzler, P.; Arko, R. A.; Chandler, C. L.; Wilson, B. D.
2013-12-01
Data citation standards can form the basis for increased incentives, recognition, and rewards for scientists. Additionally, knowing which data were utilized in a particular publication can enhance discovery and reuse. Yet, a lack of data citation information in existing publications as well as ambiguities across datasets can limit the accuracy of automated linking approaches. We describe a crowdsourcing approach, based on Linked Open Data, in which AGU abstracts are linked to the data used in those presentations. We discuss our efforts to incentivize participants through promotion of their research, the role that the Semantic Web can play in this effort, and how this work differs from existing platforms such as Mendeley and ResearchGate. Further, we discuss the benefits and challenges of Linked Open Data as a technical solution including the role of provenance, trust, and computational reasoning.
-
Guo, Jialiang; Xiao, Yuan; Lin, Yuanjing; Zhang, Qiaoxuan; Chang, Yiqun; Crommen, Jacques; Jiang, Zhengjin
2016-05-15
In order to investigate the effect of the linking spacer on the enantioseparation ability of β-cyclodextrin (β-CD) functionalized polymeric monoliths, three β-CD-functionalized organic polymeric monoliths with different spacer lengths were prepared by using three amino-β-CDs, i.e. mono-6-amino-6-deoxy-β-CD, mono-6-ethylenediamine-6-deoxy-β-CD, mono-6-hexamethylenediamine-6-deoxy-β-CD, as starting materials. These amino-β-CDs reacted with glycidyl methacrylate to produce functional monomers which were then copolymerized with ethylene dimethacrylate. The enantioseparation ability of the three monoliths was evaluated using 14 chiral acidic compounds, including mandelic acid derivatives, nonsteroidal anti-inflammatory drugs, N-derivatized amino acids, and chiral herbicides under optimum chromatographic conditions. Notably, the poly(GMA-NH2-β-CD-co-EDMA) column provides higher enantioresolution and enantioselectivity than the poly(GMA-EDA-β-CD-co-EDMA) and poly(GMA-HDA-β-CD-co-EDMA) columns for most tested chiral analytes. Furthermore, the enantioseparation performance of triazole-linker containing monoliths was compared to that of ethylenediamine-linker containing monoliths. The results indicate that the enantioselectivity of β-CD monolithic columns is strongly related to the length and type of spacer tethering β-CD to the polymeric support. Copyright © 2016 Elsevier B.V. All rights reserved.
-
Using ergonomic approaches for increasing effect of preparation at arm sport.
Directory of Open Access Journals (Sweden)
Podrigalo L.V.
2012-01-01
Full Text Available Possibility of the use of ergonometric approaches for the increase of efficiency of preparation of sportsmen of arm sport is studied. Complex research of the functional state of sportsmen of different level of trade is conducted. Corroboration legitimacy of organization of the specialized training, being based on primary development of muscles of overhead extremities. Importance of optimum capture and development of sling-dog is grounded, as a factor of success. Main and leading links are selected in providing of effectiveness. The necessity of physical development of working link (hands and brushes and association of the dynamic and static training is marked.
-
Logan, Todd; Clark, Lindsay; Ray, Soumya S
2010-07-13
Loss-of-function mutations such as L166P, A104T, and M26I in the DJ-1 gene (PARK7) have been linked to autosomal-recessive early onset Parkinson's disease (PD). Cellular and structural studies of the familial mutants suggest that these mutations may destabilize the dimeric structure. To look for common dynamical signatures among the DJ-1 mutants, short MD simulations of up to 1000 ps were conducted to identify the weakest region of the protein (residues 38-70). In an attempt to stabilize the protein, we mutated residue Val 51 to cysteine (V51C) to make a symmetry-related disulfide bridge with the preexisting Cys 53 on the opposite subunit. We found that the introduction of this disulfide linkage stabilized the mutants A104T and M26I against thermal denaturation, improved their ability to scavenge reactive oxygen species (ROS), and restored a chaperone-like function of blocking alpha-synuclein aggregation. The L166P mutant was far too unstable to be rescued by introduction of the V51C mutation. The results presented here point to the possible development of pharmacological chaperones, which may eventually lead to PD therapeutics.
-
The Link between Thyroid Function and Depression
Directory of Open Access Journals (Sweden)
Mirella P. Hage
2012-01-01
Full Text Available The relation between thyroid function and depression has long been recognized. Patients with thyroid disorders are more prone to develop depressive symptoms and conversely depression may be accompanied by various subtle thyroid abnormalities. Traditionally, the most commonly documented abnormalities are elevated T4 levels, low T3, elevated rT3, a blunted TSH response to TRH, positive antithyroid antibodies, and elevated CSF TRH concentrations. In addition, thyroid hormone supplements appear to accelerate and enhance the clinical response to antidepressant drugs. However, the mechanisms underlying the interaction between thyroid function and depression remain to be further clarified. Recently, advances in biochemical, genetic, and neuroimaging fields have provided new insights into the thyroid-depression relationship.
-
Von Economo Neurons and Fork Cells: A Neurochemical Signature Linked to Monoaminergic Function.
Dijkstra, Anke A; Lin, Li-Chun; Nana, Alissa L; Gaus, Stephanie E; Seeley, William W
2018-01-01
The human anterior cingulate and frontoinsular cortices are distinguished by 2 unique Layer 5 neuronal morphotypes, the von Economo neurons (VENs) and fork cells, whose biological identity remains mysterious. Insights could impact research on diverse neuropsychiatric diseases to which these cells have been linked. Here, we leveraged the Allen Brain Atlas to evaluate mRNA expression of 176 neurotransmitter-related genes and identified vesicular monoamine transporter 2 (VMAT2), gamma-aminobutyric acid (GABA) receptor subunit θ (GABRQ), and adrenoreceptor α-1A (ADRA1A) expression in human VENs, fork cells, and a minority of neighboring Layer 5 neurons. We confirmed these results using immunohistochemistry or in situ hybridization. VMAT2 and GABRQ expression was absent in mouse cerebral cortex. Although VMAT2 is known to package monoamines into synaptic vesicles, in VENs and fork cells its expression occurs in the absence of monoamine-synthesizing enzymes or reuptake transporters. Thus, VENs and fork cells may possess a novel, uncharacterized mode of cortical monoaminergic function that distinguishes them from most other mammalian Layer 5 neurons. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
-
The Navier-Stokes equations an elementary functional analytic approach
Sohr, Hermann
2001-01-01
The primary objective of this monograph is to develop an elementary and self-contained approach to the mathematical theory of a viscous, incompressible fluid in a domain of the Euclidean space, described by the equations of Navier-Stokes. Moreover, the theory is presented for completely general domains, in particular, for arbitrary unbounded, nonsmooth domains. Therefore, restriction was necessary to space dimensions two and three, which are also the most significant from a physical point of view. For mathematical generality, however, the linearized theory is expounded for general dimensions higher than one. Although the functional analytic approach developed here is, in principle, known to specialists, the present book fills a gap in the literature providing a systematic treatment of a subject that has been documented until now only in fragments. The book is mainly directed to students familiar with basic tools in Hilbert and Banach spaces. However, for the readers’ convenience, some fundamental properties...
-
Particle-induced bit errors in high performance fiber optic data links for satellite data management
International Nuclear Information System (INIS)
Marshall, P.W.; Carts, M.A.; Dale, C.J.; LaBel, K.A.
1994-01-01
Experimental test methods and analysis tools are demonstrated to assess particle-induced bit errors on fiber optic link receivers for satellites. Susceptibility to direct ionization from low LET particles is quantified by analyzing proton and helium ion data as a function of particle LET. Existing single event analysis approaches are shown to apply, with appropriate modifications, to the regime of temporally (rather than spatially) distributed bits, even though the sensitivity to single events exceeds conventional memory technologies by orders of magnitude. The cross-section LET dependence follows a Weibull distribution at data rates from 200 to 1,000 Mbps and at various incident optical power levels. The LET threshold for errors is shown, through both experiment and modeling, to be 0 in all cases. The error cross-section exhibits a strong inverse dependence on received optical power in the LET range where most orbital single events would occur, thus indicating that errors can be minimized by operating links with higher incident optical power. Also, an analytic model is described which incorporates the appropriate physical characteristics of the link as well as the optical and receiver electrical characteristics. Results indicate appropriate steps to assure suitable link performance even in severe particle orbits
-
Characterizing Cognitive Aging in Humans with Links to Animal Models
Directory of Open Access Journals (Sweden)
Gene E Alexander
2012-09-01
Full Text Available With the population of older adults expected to grow rapidly over the next two decades, it has become increasingly important to advance research efforts to elucidate the mechanisms associated with cognitive aging, with the ultimate goal of developing effective interventions and prevention therapies. Although there has been a vast research literature on the use of cognitive tests to evaluate the effects of aging and age-related neurodegenerative disease, the need for a set of standardized measures to characterize the cognitive profiles specific to healthy aging has been widely recognized. Here we present a review of selected methods and approaches that have been applied in human research studies to evaluate the effects of aging on cognition, including executive function, memory, processing speed, language, and visuospatial function. The effects of healthy aging on each of these cognitive domains are discussed with examples from cognitive/experimental and clinical/neuropsychological approaches. Further, we consider those measures that have clear conceptual and methodological links to tasks currently in use for non-human animal studies of aging, as well as those that have the potential for translation to animal aging research. Having a complementary set of measures to assess the cognitive profiles of healthy aging across species provides a unique opportunity to enhance research efforts for cross-sectional, longitudinal, and intervention studies of cognitive aging. Taking a cross-species, translational approach will help to advance cognitive aging research, leading to a greater understanding of associated neurobiological mechanisms with the potential for developing effective interventions and prevention therapies for age-related cognitive decline.
-
Fei, Xiang; Zavorka, Megan E; Malik, Guillaume; Connelly, Christopher M; MacDonald, Richard G; Berkowitz, David B
2017-08-18
A generalized strategy is presented for the rapid assembly of a set of bivalent ligands with a variety of linking functionalities from a common monomer. Herein, an array of phosphatase-inert mannose-6-phosphonate-presenting ligands for the cation-independent-mannose 6-phosphate receptor (CI-MPR) is constructed. Receptor binding affinity varies with linking functionality-the simple amide and 1,5-triazole(tetrazole) being preferred over the 1,4-triazole. This approach is expected to find application across chemical biology, particularly in glycoscience, wherein multivalency often governs molecular recognition.
-
Linking stem cell function and growth pattern of intestinal organoids.
Thalheim, Torsten; Quaas, Marianne; Herberg, Maria; Braumann, Ulf-Dietrich; Kerner, Christiane; Loeffler, Markus; Aust, Gabriela; Galle, Joerg
2018-01-15
Intestinal stem cells (ISCs) require well-defined signals from their environment in order to carry out their specific functions. Most of these signals are provided by neighboring cells that form a stem cell niche, whose shape and cellular composition self-organize. Major features of this self-organization can be studied in ISC-derived organoid culture. In this system, manipulation of essential pathways of stem cell maintenance and differentiation results in well-described growth phenotypes. We here provide an individual cell-based model of intestinal organoids that enables a mechanistic explanation of the observed growth phenotypes. In simulation studies of the 3D structure of expanding organoids, we investigate interdependences between Wnt- and Notch-signaling which control the shape of the stem cell niche and, thus, the growth pattern of the organoids. Similar to in vitro experiments, changes of pathway activities alter the cellular composition of the organoids and, thereby, affect their shape. Exogenous Wnt enforces transitions from branched into a cyst-like growth pattern; known to occur spontaneously during long term organoid expansion. Based on our simulation results, we predict that the cyst-like pattern is associated with biomechanical changes of the cells which assign them a growth advantage. The results suggest ongoing stem cell adaptation to in vitro conditions during long term expansion by stabilizing Wnt-activity. Our study exemplifies the potential of individual cell-based modeling in unraveling links between molecular stem cell regulation and 3D growth of tissues. This kind of modeling combines experimental results in the fields of stem cell biology and cell biomechanics constituting a prerequisite for a better understanding of tissue regeneration as well as developmental processes. Copyright © 2017 Elsevier Inc. All rights reserved.
-
DEFF Research Database (Denmark)
Stradi, Daniele; Martinez, Umberto; Blom, Anders
2016-01-01
Metal-semiconductor contacts are a pillar of modern semiconductor technology. Historically, their microscopic understanding has been hampered by the inability of traditional analytical and numerical methods to fully capture the complex physics governing their operating principles. Here we introduce...... an atomistic approach based on density functional theory and nonequilibrium Green's function, which includes all the relevant ingredients required to model realistic metal-semiconductor interfaces and allows for a direct comparison between theory and experiments via I-Vbias curve simulations. We apply...... interfaces as it neglects electron tunneling, and that finite-size atomistic models have problems in describing these interfaces in the presence of doping due to a poor representation of space-charge effects. Conversely, the present method deals effectively with both issues, thus representing a valid...
-
Educability as a Link of Contemporary Civil Experience: Research Approaches
Directory of Open Access Journals (Sweden)
Julio Groppa Aquino
2016-05-01
Full Text Available This text argues that the educability of citizens is objectified in terms of a demand for diffuse and perpetual training, which has become a foundational link of social existence. This statement is based upon the results of twelve researches carried out by a group from the school of Education of the University of São Paulo, devoted to Foucaultian studies in education. It is an effort to analyze the relationship between contemporary governmentality and certain ongoing educational imperatives from different social fields.
-
Detection of deregulated modules using deregulatory linked path.
Directory of Open Access Journals (Sweden)
Yuxuan Hu
Full Text Available The identification of deregulated modules (such as induced by oncogenes is a crucial step for exploring the pathogenic process of complex diseases. Most of the existing methods focus on deregulation of genes rather than the links of the path among them. In this study, we emphasize on the detection of deregulated links, and develop a novel and effective regulatory path-based approach in finding deregulated modules. Observing that a regulatory pathway between two genes might involve in multiple rather than a single path, we identify condition-specific core regulatory path (CCRP to detect the significant deregulation of regulatory links. Using time-series gene expression, we define the regulatory strength within each gene pair based on statistical dependence analysis. The CCRPs in regulatory networks can then be identified using the shortest path algorithm. Finally, we derive the deregulated modules by integrating the differential edges (as deregulated links of the CCRPs between the case and the control group. To demonstrate the effectiveness of our approach, we apply the method to expression data associated with different states of Human Epidermal Growth Factor Receptor 2 (HER2. The experimental results show that the genes as well as the links in the deregulated modules are significantly enriched in multiple KEGG pathways and GO biological processes, most of which can be validated to suffer from impact of this oncogene based on previous studies. Additionally, we find the regulatory mechanism associated with the crucial gene SNAI1 significantly deregulated resulting from the activation of HER2. Hence, our method provides not only a strategy for detecting the deregulated links in regulatory networks, but also a way to identify concerning deregulated modules, thus contributing to the target selection of edgetic drugs.
-
Modeling of Atmospheric Turbulence Effect on Terrestrial FSO Link
Directory of Open Access Journals (Sweden)
A. Prokes
2009-04-01
Full Text Available Atmospheric turbulence results in many effects causing fluctuation in the received optical power. Terrestrial laser beam communication is affected above all by scintillations. The paper deals with modeling the influence of scintillation on link performance, using the modified Rytov theory. The probability of correct signal detection in direct detection system in dependence on many parameters such as link distance, power link margin, refractive-index structure parameter, etc. is discussed and different approaches to the evaluation of scintillation effect are compared. The simulations are performed for a horizontal-path propagation of the Gaussian-beam wave.
-
[Linked Data as a tool in the nutrition domain].
Míguez Pérez, R; Santos Gago, J M; Alonso Rorís, V M; Álvarez Sabucedo, L M; Mikic Fonte, F A
2012-01-01
Currently, there is a huge amount of information available on Internet that can neither be interpreted nor used by software agents. This fact poses a serious drawback to the potential of tools that deal with data on the current Web. Nevertheless, in recent times, advances in the domain of Semantic Web make possible the development of a new generation of smart applications capable of creating added-value services for the final user. This work shows the technical challenges that must be faced in the area of nutrition in order to transform one or several oldfashion sources of raw data into a web repository based on semantic technologies and linked with external and publicly available data on Internet. This approach makes possible for automatic tools to operate on the top of this information providing new functionalities highly interesting in the domain of public health, such as the automatic generation of menus for children or intelligent dietetic assistants, among others. This article explains the process to create such information support applying the guidelines of the Linked Data initiative and provides insights into the use of tools to make the most of this technology for its adoption in related use cases and environments.
-
A marketing-finance approach linking contracts in agricultural channels to shareholder value
Pennings, J.M.E.; Wansink, B.; Hoffmann, A.O.I.
2011-01-01
A conceptual marketing-finance framework is proposed which links channel contracting in agriculture and the use of financial facilitating services (e.g., financial derivatives) to (shareholder) value creation. The framework complements existing literature by explicitly including channel contract
-
Pellicano, Elizabeth
2007-07-01
There has been much theoretical discussion of a functional link between theory of mind (ToM) and executive function (EF) in autism. This study sought to establish the relationship between ToM and EF in young children with autism (M = 5 years, 6 months) and to examine issues of developmental primacy. Thirty children with autism and 40 typically developing children, matched on age and ability, were assessed on a battery of tasks measuring ToM (1st- and 2nd-order false belief) and components of EF (planning, set shifting, inhibition). A significant correlation emerged between ToM and EF variables in the autism group, independent of age and ability, while ToM and higher order planning ability remained significantly related in the comparison group. Examination of the pattern of ToM-EF impairments in the autism group revealed dissociations in 1 direction only: impaired ToM with intact EF. These findings support the view that EF may be 1 important factor in the advancement of ToM understanding in autism. The theoretical implications of these findings are discussed. Copyright 2007 APA.
-
Linking structural features of protein complexes and biological function.
Sowmya, Gopichandran; Breen, Edmond J; Ranganathan, Shoba
2015-09-01
Protein-protein interaction (PPI) establishes the central basis for complex cellular networks in a biological cell. Association of proteins with other proteins occurs at varying affinities, yet with a high degree of specificity. PPIs lead to diverse functionality such as catalysis, regulation, signaling, immunity, and inhibition, playing a crucial role in functional genomics. The molecular principle of such interactions is often elusive in nature. Therefore, a comprehensive analysis of known protein complexes from the Protein Data Bank (PDB) is essential for the characterization of structural interface features to determine structure-function relationship. Thus, we analyzed a nonredundant dataset of 278 heterodimer protein complexes, categorized into major functional classes, for distinguishing features. Interestingly, our analysis has identified five key features (interface area, interface polar residue abundance, hydrogen bonds, solvation free energy gain from interface formation, and binding energy) that are discriminatory among the functional classes using Kruskal-Wallis rank sum test. Significant correlations between these PPI interface features amongst functional categories are also documented. Salt bridges correlate with interface area in regulator-inhibitors (r = 0.75). These representative features have implications for the prediction of potential function of novel protein complexes. The results provide molecular insights for better understanding of PPIs and their relation to biological functions. © 2015 The Protein Society.
-
Forghani, Masoomeh; Ghanbari Hashem Abadi, Bahram Ali
2016-06-01
The aim of the present study was to evaluate the effect of group psychotherapy with transactional analysis (TA) approach on emotional intelligence (EI), executive functions and substance dependency among drug-addicts at rehabilitation centers in Mashhad city, Iran, in 2013. In this quasi-experimental study with pretest, posttest, case- control stages, 30 patients were selected from a rehabilitation center and randomly divided into two groups. The case group received 12 sessions of group psychotherapy with transactional analysis approach. Then the effects of independent variable (group psychotherapy with TA approach) on EI, executive function and drug dependency were assessed. The Bar-on test was used for EI, Stroop test for measuring executive function and morphine test, meth-amphetamines and B2 test for evaluating drug dependency. Data were analyzed using multifactorial covariance analysis, Levenes' analysis, MANCOVA, t-student and Pearson correlation coefficient tests t with SPSS software. Our results showed that group psychotherapy with the TA approach was effective in improving EI, executive functions and decreasing drug dependency (P addicts and prevents addiction recurrence by improving the coping capabilities and some mental functions of the subjects. However, there are some limitations regarding this study including follow-up duration and sample size.
-
Links in a distributed database: Theory and implementation
International Nuclear Information System (INIS)
Karonis, N.T.; Kraimer, M.R.
1991-12-01
This document addresses the problem of extending database links across Input/Output Controller (IOC) boundaries. It lays a foundation by reviewing the current system and proposing an implementation specification designed to guide all work in this area. The document also describes an implementation that is less ambitious than our formally stated proposal, one that does not extend the reach of all database links across IOC boundaries. Specifically, it introduces an implementation of input and output links and comments on that overall implementation. We include a set of manual pages describing each of the new functions the implementation provides
-
Yurchenko, Sergei N; Yachmenev, Andrey; Ovsyannikov, Roman I
2017-09-12
We present a general, numerically motivated approach to the construction of symmetry-adapted basis functions for solving ro-vibrational Schrödinger equations. The approach is based on the property of the Hamiltonian operator to commute with the complete set of symmetry operators and, hence, to reflect the symmetry of the system. The symmetry-adapted ro-vibrational basis set is constructed numerically by solving a set of reduced vibrational eigenvalue problems. In order to assign the irreducible representations associated with these eigenfunctions, their symmetry properties are probed on a grid of molecular geometries with the corresponding symmetry operations. The transformation matrices are reconstructed by solving overdetermined systems of linear equations related to the transformation properties of the corresponding wave functions on the grid. Our method is implemented in the variational approach TROVE and has been successfully applied to many problems covering the most important molecular symmetry groups. Several examples are used to illustrate the procedure, which can be easily applied to different types of coordinates, basis sets, and molecular systems.
-
Coplan, Robert J.; Rose-Krasnor, Linda; Weeks, Murray; Kingsbury, Adam; Kingsbury, Mila; Bullock, Amanda
2013-01-01
The primary goals of this study were to test a conceptual model linking social approach and avoidance motivations, socially withdrawn behaviors, and peer difficulties in later childhood and to compare the socioemotional functioning of different subtypes of withdrawn children (shy, unsociable, avoidant). Participants were 367 children, aged 9-12…
-
Impression management and achievement motivation:Investigating substantive links
Elliot, Andrew J.; Aldhobaiban, Nawal; Murayama, Kou; Kobeisy, Ahmed; Gocłowska, Małgorzata A.; Khyat, Aber
2018-01-01
In the present research we investigate impression management (IM) as a substantive personality variable by linking it to differentiated achievement motivation constructs, namely achievement motives (workmastery, competitiveness, fear of failure) and achievement goals (mastery-approach, mastery-avoidance, performance-approach, performance-avoidance). Study 1 revealed that IM was a positive predictor of workmastery and a negative predictor of competitiveness (with and without self-deceptive enh...