Advertising Via Mobile Terminals - Delivering Context Sensitive and Personalized Advertising While Guaranteeing Privacy

NASA Astrophysics Data System (ADS)

Bulander, Rebecca; Decker, Michael; Schiefer, Gunther; Kölmel, Bernhard

Mobile terminals like cellular phones and PDAs are a promising target platform for mobile advertising: The devices are widely spread, are able to present interactive multimedia content and offer as almost permanently carried along personal communication devices a high degree of reachability. But particular because of the latter feature it is important to pay great attention to privacy aspects and avoidance of spam-messages when designing an application for mobile advertising. Furthermore the limited user interface of mobile devices is a special challenge. The following article describes the solution approach for mobile advertising developed within the project MoMa, which was funded by the Federal Ministry of Economics and Labour of Germany (BMWA). MoMa enables highly personalized and context sensitive mobile advertising while guaranteeing data protection. To achieve this we have to distinguish public and private context information.

Verification and Optimal Control of Context-Sensitive Probabilistic Boolean Networks Using Model Checking and Polynomial Optimization

PubMed Central

Hiraishi, Kunihiko

2014-01-01

One of the significant topics in systems biology is to develop control theory of gene regulatory networks (GRNs). In typical control of GRNs, expression of some genes is inhibited (activated) by manipulating external stimuli and expression of other genes. It is expected to apply control theory of GRNs to gene therapy technologies in the future. In this paper, a control method using a Boolean network (BN) is studied. A BN is widely used as a model of GRNs, and gene expression is expressed by a binary value (ON or OFF). In particular, a context-sensitive probabilistic Boolean network (CS-PBN), which is one of the extended models of BNs, is used. For CS-PBNs, the verification problem and the optimal control problem are considered. For the verification problem, a solution method using the probabilistic model checker PRISM is proposed. For the optimal control problem, a solution method using polynomial optimization is proposed. Finally, a numerical example on the WNT5A network, which is related to melanoma, is presented. The proposed methods provide us useful tools in control theory of GRNs. PMID:24587766

Anomalously large effects of pressure on electron transfer kinetics in solution: The aqueous manganate(VI)-permanganate(VII) system

NASA Astrophysics Data System (ADS)

Swaddle, T. W.; Spiccia, L.

1986-05-01

The classical Stranks-Hush-Marcus theory of pressure effects on the rates of outer-sphere electron transfer reaction rates in solution underestimates |ΔV ∗| specifically, for the MnO 4/MnO 42- (aq) exchange, ΔV ∗=-21.2 (observed) vs. -6.6 cm3mol-1 (calculated). This discrepancy can best be resolved by conceding that the Mn-Mn separation σ in the transition state is variable and pressure-sensitive in the context of non-adiabatic electron transfer within an ellipsoidal cavity with σ ∼ 550 pm.

Adjoint shape optimization for fluid-structure interaction of ducted flows

NASA Astrophysics Data System (ADS)

Heners, J. P.; Radtke, L.; Hinze, M.; Düster, A.

2018-03-01

Based on the coupled problem of time-dependent fluid-structure interaction, equations for an appropriate adjoint problem are derived by the consequent use of the formal Lagrange calculus. Solutions of both primal and adjoint equations are computed in a partitioned fashion and enable the formulation of a surface sensitivity. This sensitivity is used in the context of a steepest descent algorithm for the computation of the required gradient of an appropriate cost functional. The efficiency of the developed optimization approach is demonstrated by minimization of the pressure drop in a simple two-dimensional channel flow and in a three-dimensional ducted flow surrounded by a thin-walled structure.

Thermodynamic modeling of transcription: sensitivity analysis differentiates biological mechanism from mathematical model-induced effects.

PubMed

Dresch, Jacqueline M; Liu, Xiaozhou; Arnosti, David N; Ay, Ahmet

2010-10-24

Quantitative models of gene expression generate parameter values that can shed light on biological features such as transcription factor activity, cooperativity, and local effects of repressors. An important element in such investigations is sensitivity analysis, which determines how strongly a model's output reacts to variations in parameter values. Parameters of low sensitivity may not be accurately estimated, leading to unwarranted conclusions. Low sensitivity may reflect the nature of the biological data, or it may be a result of the model structure. Here, we focus on the analysis of thermodynamic models, which have been used extensively to analyze gene transcription. Extracted parameter values have been interpreted biologically, but until now little attention has been given to parameter sensitivity in this context. We apply local and global sensitivity analyses to two recent transcriptional models to determine the sensitivity of individual parameters. We show that in one case, values for repressor efficiencies are very sensitive, while values for protein cooperativities are not, and provide insights on why these differential sensitivities stem from both biological effects and the structure of the applied models. In a second case, we demonstrate that parameters that were thought to prove the system's dependence on activator-activator cooperativity are relatively insensitive. We show that there are numerous parameter sets that do not satisfy the relationships proferred as the optimal solutions, indicating that structural differences between the two types of transcriptional enhancers analyzed may not be as simple as altered activator cooperativity. Our results emphasize the need for sensitivity analysis to examine model construction and forms of biological data used for modeling transcriptional processes, in order to determine the significance of estimated parameter values for thermodynamic models. Knowledge of parameter sensitivities can provide the necessary context to determine how modeling results should be interpreted in biological systems.

Differential effects of context on psychomotor sensitization to ethanol and cocaine.

PubMed

Didone, Vincent; Quoilin, Caroline; Dieupart, Julie; Tirelli, Ezio; Quertemont, Etienne

2016-04-01

Repeated drug injections lead to sensitization of their stimulant effects in mice, a phenomenon sometimes referred to as drug psychomotor sensitization. Previous studies showed that sensitization to cocaine is context dependent as its expression is reduced in an environment that was not paired with cocaine administration. In contrast, the effects of the test context on ethanol sensitization remain unclear. In the present study, female OF1 mice were repeatedly injected with 1.5 g/kg ethanol to test for both the effects of context novelty/familiarity and association on ethanol sensitization. A first group of mice was extensively pre-exposed to the test context before ethanol sensitization and ethanol injections were paired with the test context (familiar and paired group). A second group was not pre-exposed to the test context, but ethanol injections were paired with the test context (nonfamiliar and paired group). Finally, a third group of mice was not pre-exposed to the test context and ethanol was repeatedly injected in the home cage (unpaired group). Control groups were similarly exposed to the test context, but were injected with saline. In a second experiment, cocaine was used as a positive control. The same behavioral procedure was used, except that mice were injected with 10 mg/kg cocaine instead of ethanol. The results show a differential involvement of the test context in the sensitization to ethanol and cocaine. Cocaine sensitization is strongly context dependent and is not expressed in the unpaired group. In contrast, the expression of ethanol sensitization is independent of the context in which it was administered, but is strongly affected by the relative novelty/familiarity of the environment. Extensive pre-exposure to the test context prevented the expression of ethanol sensitization. One possible explanation is that expression of ethanol sensitization requires an arousing environment.

Extreme sensitivity biosensing platform based on hyperbolic metamaterials

NASA Astrophysics Data System (ADS)

Sreekanth, Kandammathe Valiyaveedu; Alapan, Yunus; Elkabbash, Mohamed; Ilker, Efe; Hinczewski, Michael; Gurkan, Umut A.; de Luca, Antonio; Strangi, Giuseppe

2016-06-01

Optical sensor technology offers significant opportunities in the field of medical research and clinical diagnostics, particularly for the detection of small numbers of molecules in highly diluted solutions. Several methods have been developed for this purpose, including label-free plasmonic biosensors based on metamaterials. However, the detection of lower-molecular-weight (<500 Da) biomolecules in highly diluted solutions is still a challenging issue owing to their lower polarizability. In this context, we have developed a miniaturized plasmonic biosensor platform based on a hyperbolic metamaterial that can support highly confined bulk plasmon guided modes over a broad wavelength range from visible to near infrared. By exciting these modes using a grating-coupling technique, we achieved different extreme sensitivity modes with a maximum of 30,000 nm per refractive index unit (RIU) and a record figure of merit (FOM) of 590. We report the ability of the metamaterial platform to detect ultralow-molecular-weight (244 Da) biomolecules at picomolar concentrations using a standard affinity model streptavidin-biotin.

Context-aware pattern discovery for moving object trajectories

NASA Astrophysics Data System (ADS)

Sharif, Mohammad; Asghar Alesheikh, Ali; Kaffash Charandabi, Neda

2018-05-01

Movement of point objects are highly sensitive to the underlying situations and conditions during the movement, which are known as contexts. Analyzing movement patterns, while accounting the contextual information, helps to better understand how point objects behave in various contexts and how contexts affect their trajectories. One potential solution for discovering moving objects patterns is analyzing the similarities of their trajectories. This article, therefore, contextualizes the similarity measure of trajectories by not only their spatial footprints but also a notion of internal and external contexts. The dynamic time warping (DTW) method is employed to assess the multi-dimensional similarities of trajectories. Then, the results of similarity searches are utilized in discovering the relative movement patterns of the moving point objects. Several experiments are conducted on real datasets that were obtained from commercial airplanes and the weather information during the flights. The results yielded the robustness of DTW method in quantifying the commonalities of trajectories and discovering movement patterns with 80 % accuracy. Moreover, the results revealed the importance of exploiting contextual information because it can enhance and restrict movements.

Religious beliefs are factual beliefs: Content does not correlate with context sensitivity.

PubMed

Levy, Neil

2017-04-01

Neil Van Leeuwen argues that religious beliefs are not factual beliefs: typically, at least, they are attitudes of a different type. He argues that they exhibit much more sensitivity to context than factual beliefs: outside of contexts in which they are salient, they do not govern behaviour or inference, or provide background assumptions for cognition. This article surveys a large range of data to show that the kind of context sensitivity that Van Leeuwen thinks is the province of religious beliefs does not correlate with belief content. Beliefs about matters of fact beyond the theological realm exhibit this kind of sensitivity too. Conversely, theological and supernatural beliefs often guide behaviour across contexts. It is the intuitiveness of representations across contexts that predicts context (in)sensitivity, and intuitiveness is powerfully influenced by processing fluency. Fluency, in turn, is sensitive to cues that vary across contexts. Copyright © 2017 Elsevier B.V. All rights reserved.

Context-dependent catalepsy intensification is due to classical conditioning and sensitization.

PubMed

Amtage, J; Schmidt, W J

2003-11-01

Haloperidol-induced catalepsy represents a model of neuroleptic-induced Parkinsonism. Daily administration of haloperidol, followed by testing for catalepsy on a bar and grid, results in a day-to-day increase in catalepsy that is completely context dependent, resulting in a strong placebo effect and in a failure of expression after a change in context. The aim of this study was to analyse the associative learning process that underlies context dependency. Catalepsy intensification was induced by a daily threshold dose of 0.25 mg/kg haloperidol. Extinction training and retesting under haloperidol revealed that sensitization was composed of two components: a context-conditioning component, which can be extinguished, and a context-dependent sensitization component, which cannot be extinguished. Context dependency of catalepsy thus follows precisely the same rules as context dependency of psychostimulant-induced sensitization. Catalepsy sensitization is therefore due to conditioning and sensitization.

Photonic molecules for application in silicon-on-insulator optical sensors

NASA Astrophysics Data System (ADS)

Barea, Luis A. M.; Souza, Mario C. M. M.; Moras, Andre L.; Catellan, Alvaro R. G.; Cirino, Giuseppe A.; Von Zuben, Antonio A. G.; Bassani, Jose W. M.; Frateschi, Newton C.

2018-02-01

Optical sensors based on integrated photonics have experienced impressive advancements in the past few decades and represent one of the main sensing solutions in many areas including environmental sensing and medical diagnostics. In this context, optical microcavities are extensively employed as refractive index (RI) sensors, providing sharp optical resonances that allow the detection of very small variations in the surrounding RI. With increased sensitivity, however, the device is subjected to environmental perturbations that can also change the RI, such as temperature variations, and therefore compromise their reliability. In this work, we present the concept and experimental realization of a photonic sensor based on coupled microcavities or Photonic Molecules (PM) in which only one cavity is exposed to the sensing solution, allowing a differential measurement of the RI change. The device consists of an exposed 5-μm radius microdisk resonator coupled to an external clad microring resonator fabricated on silicon-on-insulator (SOI) platform. This design allows good sensitivity (26 nm/RIU) for transverse electrical mode (TE-mode) in a compact footprint (40 × 40 μm2), representing a good solution for real-life applications in which measurement conditions are not easily controllable.

Measuring personal recovery - psychometric properties of the Swedish Questionnaire about the Process of Recovery (QPR-Swe).

PubMed

Argentzell, Elisabeth; Hultqvist, Jenny; Neil, Sandra; Eklund, Mona

2017-10-01

Personal recovery, defined as an individual process towards meaning, is an important target within mental health services. Measuring recovery hence requires reliable and valid measures. The Process of Recovery Questionnaire (QPR) was developed for that purpose. The aim was to develop a Swedish version of the QPR (QPR-Swe) and explore its psychometric properties in terms of factor structure, internal consistency, construct validity and sensitivity to change. A total of 226 participants entered the study. The factor structure was investigated by Principal Component Analysis and Scree plot. Construct validity was addressed in terms of convergent validity against indicators of self-mastery, self-esteem, quality of life and self-rated health. A one-factor solution of QPR-Swe received better support than a two-factor solution. Good internal consistency was indicated, α = 0.92, and construct validity was satisfactory. The QPR-Swe showed preliminary sensitivity to change. The QPR-Swe showed promising initial psychometric properties in terms of internal consistency, convergent validity and sensitivity to change. The QPR-Swe is recommended for use in research and clinical contexts to assess personal recovery among people with mental illness.

Child Conduct Problems across Home and School Contexts: A Person-Centered Approach

PubMed Central

Sulik, Michael J.; Blair, Clancy; Greenberg, Mark

2018-01-01

To examine patterns of conduct problems across the home and school context, we used latent class analysis to analyze primary caregivers' and teachers' ratings on the conduct problems subscale of the Strengths and Difficulties Questionnaire (R. Goodman, 1997) in the Family Life Project (N = 1,292), a prospective study of child development in rural and small town contexts. We found a similar four-class solution at five and seven years of age. In decreasing prevalence, the following classes were identified: (1) low symptoms reported by both informants (low cross-context); (2) high parent-reported symptoms, low teacher-reported symptoms (home context); (3) low parent-reported symptoms, moderate teacher-reported symptoms (school context); and (4) high symptoms reported by both informants (high cross-context). Classes exhibited stability from age five to age seven: children were more likely to remain in the same class than to transition to a different class, and longitudinal stability was especially high for children in the low cross-context class at age 5. A number of child and family characteristics measured in early childhood (executive function, verbal ability, poverty-related risk, sensitive parenting, and parental depressive symptoms) were associated with class membership at age five and age seven, but were generally not associated with longitudinal transitions between classes. PMID:29720784

Evaluating the combined effects of source zone mass release rates and aquifer heterogeneity on solute discharge uncertainty

NASA Astrophysics Data System (ADS)

de Barros, Felipe P. J.

2018-07-01

Quantifying the uncertainty in solute mass discharge at an environmentally sensitive location is key to assess the risks due to groundwater contamination. Solute mass fluxes are strongly affected by the spatial variability of hydrogeological properties as well as release conditions at the source zone. This paper provides a methodological framework to investigate the interaction between the ubiquitous heterogeneity of the hydraulic conductivity and the mass release rate at the source zone on the uncertainty of mass discharge. Through the use of perturbation theory, we derive analytical and semi-analytical expressions for the statistics of the solute mass discharge at a control plane in a three-dimensional aquifer while accounting for the solute mass release rates at the source. The derived solutions are limited to aquifers displaying low-to-mild heterogeneity. Results illustrate the significance of the source zone mass release rate in controlling the mass discharge uncertainty. The relative importance of the mass release rate on the mean solute discharge depends on the distance between the source and the control plane. On the other hand, we find that the solute release rate at the source zone has a strong impact on the variance of the mass discharge. Within a risk context, we also compute the peak mean discharge as a function of the parameters governing the spatial heterogeneity of the hydraulic conductivity field and mass release rates at the source zone. The proposed physically-based framework is application-oriented, computationally efficient and capable of propagating uncertainty from different parameters onto risk metrics. Furthermore, it can be used for preliminary screening purposes to guide site managers to perform system-level sensitivity analysis and better allocate resources.

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

NASA Astrophysics Data System (ADS)

Shadid, J. N.; Smith, T. M.; Cyr, E. C.; Wildey, T. M.; Pawlowski, R. P.

2016-09-01

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. In this respect the understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In this study we report on initial efforts to apply integrated adjoint-based computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier-Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. Initial results are presented that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

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

Shadid, J.N., E-mail: jnshadi@sandia.gov; Department of Mathematics and Statistics, University of New Mexico; Smith, T.M.

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. In this respect the understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In this study we report on initial efforts tomore » apply integrated adjoint-based computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier–Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. Initial results are presented that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.« less

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

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

Shadid, J. N.; Smith, T. M.; Cyr, E. C.

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. The understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In our study we report on initial efforts to apply integrated adjoint-basedmore » computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier–Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. We present the initial results that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.« less

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

DOE PAGES

Shadid, J. N.; Smith, T. M.; Cyr, E. C.; ...

2016-05-20

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. The understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In our study we report on initial efforts to apply integrated adjoint-basedmore » computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier–Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. We present the initial results that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.« less

Conditional solvation thermodynamics of isoleucine in model peptides and the limitations of the group-transfer model.

PubMed

Tomar, Dheeraj S; Weber, Valéry; Pettitt, B Montgomery; Asthagiri, D

2014-04-17

The hydration thermodynamics of the amino acid X relative to the reference G (glycine) or the hydration thermodynamics of a small-molecule analog of the side chain of X is often used to model the contribution of X to protein stability and solution thermodynamics. We consider the reasons for successes and limitations of this approach by calculating and comparing the conditional excess free energy, enthalpy, and entropy of hydration of the isoleucine side chain in zwitterionic isoleucine, in extended penta-peptides, and in helical deca-peptides. Butane in gauche conformation serves as a small-molecule analog for the isoleucine side chain. Parsing the hydrophobic and hydrophilic contributions to hydration for the side chain shows that both of these aspects of hydration are context-sensitive. Furthermore, analyzing the solute-solvent interaction contribution to the conditional excess enthalpy of the side chain shows that what is nominally considered a property of the side chain includes entirely nonobvious contributions of the background. The context-sensitivity of hydrophobic and hydrophilic hydration and the conflation of background contributions with energetics attributed to the side chain limit the ability of a single scaling factor, such as the fractional solvent exposure of the group in the protein, to map the component energetic contributions of the model-compound data to their value in the protein. But ignoring the origin of cancellations in the underlying components the group-transfer model may appear to provide a reasonable estimate of the free energy for a given error tolerance.

Inferring Human Activity in Mobile Devices by Computing Multiple Contexts.

PubMed

Chen, Ruizhi; Chu, Tianxing; Liu, Keqiang; Liu, Jingbin; Chen, Yuwei

2015-08-28

This paper introduces a framework for inferring human activities in mobile devices by computing spatial contexts, temporal contexts, spatiotemporal contexts, and user contexts. A spatial context is a significant location that is defined as a geofence, which can be a node associated with a circle, or a polygon; a temporal context contains time-related information that can be e.g., a local time tag, a time difference between geographical locations, or a timespan; a spatiotemporal context is defined as a dwelling length at a particular spatial context; and a user context includes user-related information that can be the user's mobility contexts, environmental contexts, psychological contexts or social contexts. Using the measurements of the built-in sensors and radio signals in mobile devices, we can snapshot a contextual tuple for every second including aforementioned contexts. Giving a contextual tuple, the framework evaluates the posteriori probability of each candidate activity in real-time using a Naïve Bayes classifier. A large dataset containing 710,436 contextual tuples has been recorded for one week from an experiment carried out at Texas A&M University Corpus Christi with three participants. The test results demonstrate that the multi-context solution significantly outperforms the spatial-context-only solution. A classification accuracy of 61.7% is achieved for the spatial-context-only solution, while 88.8% is achieved for the multi-context solution.

East-West Cultural Differences in Context-sensitivity are Evident in Early Childhood

PubMed Central

Imada, Toshie; Carlson, Stephanie M.; Itakura, Shoji

2018-01-01

Accumulating evidence suggests North Americans tend to focus on central objects whereas East Asians tend to pay more attention to contextual information in a visual scene. Although it is generally believed that such culturally divergent attention tendencies develop through socialization, existing evidence largely depends on adult samples. Moreover, no past research has investigated the relation between context-sensitivity and other domains of cognitive development. The present study investigated children in the United States and Japan (N = 175, age 4–9 years) to examine the developmental pattern in context-sensitivity and its relation to executive function. The study found that context-sensitivity increased with age across cultures. Nevertheless, Japanese children showed significantly greater context-sensitivity than American children. Also, context-sensitivity fully mediated the cultural difference in a set-shifting executive function task, which might help explain past findings that East-Asian children outperformed their American counterparts on executive function. PMID:23432830

Multi-Dimensional Pattern Discovery of Trajectories Using Contextual Information

NASA Astrophysics Data System (ADS)

Sharif, M.; Alesheikh, A. A.

2017-10-01

Movement of point objects are highly sensitive to the underlying situations and conditions during the movement, which are known as contexts. Analyzing movement patterns, while accounting the contextual information, helps to better understand how point objects behave in various contexts and how contexts affect their trajectories. One potential solution for discovering moving objects patterns is analyzing the similarities of their trajectories. This article, therefore, contextualizes the similarity measure of trajectories by not only their spatial footprints but also a notion of internal and external contexts. The dynamic time warping (DTW) method is employed to assess the multi-dimensional similarities of trajectories. Then, the results of similarity searches are utilized in discovering the relative movement patterns of the moving point objects. Several experiments are conducted on real datasets that were obtained from commercial airplanes and the weather information during the flights. The results yielded the robustness of DTW method in quantifying the commonalities of trajectories and discovering movement patterns with 80 % accuracy. Moreover, the results revealed the importance of exploiting contextual information because it can enhance and restrict movements.

Characterization of pH-sensitive hydrogels by conductimetry and calorimetry

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

Sheppard, N.F. Jr.; Chen, Jey-Hsin; Lawson, H.C.

1993-12-31

The total and freezing water contents, and electrical conductivity of pH-sensitive hydrogels formed from poly(hydroxyethyl methacrylate - co - dimethylaminoethyl methacrylate) were measured as a function of copolymer composition and pH. For an 80/20 HEMA/DMAEMA gel (mole ratio), the water content increases from 37% at pH 10 of the bathing solution value at pH 10 to 90% at low pH. The difference between total and freezing water content in the gels is approximately 25%, consistent with values reported in the literature. An examination of the results in the context of the Yasuda free- volume model suggests that freezing water content,more » rather than total water content, may be suitable for modelling of hydrogel conductivity.« less

Cultural, gender, and socioeconomic contexts in therapeutic and social policy work.

PubMed

Waldegrave, Charles

2009-03-01

The contention of this paper is that the context of social and therapeutic problems is critical to their resolution, and that many of them stem from historical and structural injustice. It focuses on the contextual issues of cultural, gender, and socioeconomic equity as providing important insights into authentic notions of social inclusion and well-being, and encourages therapists, service providers, researchers, and policy makers to take responsibility to ensure that these injustices are addressed, and become part of the public discourse about the sources and solutions of endemic social problems. Critique and deconstruction of institutional power in our public, private, and voluntary services is encouraged in a manner that honors diversity and enables sensitive therapy, other forms of service delivery and policy making that genuinely reflect the range of cultural, gender, and socioeconomic experiences of citizens.

Neurocognitive assessment of emotional context sensitivity.

PubMed

Myruski, Sarah; Bonanno, George A; Gulyayeva, Olga; Egan, Laura J; Dennis-Tiwary, Tracy A

2017-10-01

Sensitivity to emotional context is an emerging construct for characterizing adaptive or maladaptive emotion regulation, but few measurement approaches exist. The current study combined behavioral and neurocognitive measures to assess context sensitivity in relation to self-report measures of adaptive emotional flexibility and well-being. Sixty-six adults completed an emotional go/no-go task using happy, fearful, and neutral faces as go and no-go cues, while EEG was recorded to generate event-related potentials (ERPs) reflecting attentional selection and discrimination (N170) and cognitive control (N2). Context sensitivity was measured as the degree of emotional facilitation or disruption in the go/no-go task and magnitude of ERP response to emotion cues. Participants self-reported on emotional flexibility, anxiety, and depression. Overall participants evidenced emotional context sensitivity, such that when happy faces were go stimuli, accuracy improved (greater behavioral facilitation), whereas when fearful faces were no-go stimuli, errors increased (disrupted behavioral inhibition). These indices predicted emotional flexibility and well-being: Greater behavioral facilitation following happy cues was associated with lower depression and anxiety, whereas greater disruption in behavioral inhibition following fearful cues was associated with lower flexibility. ERP indices of context sensitivity revealed additional associations: Greater N2 to fear go cues was associated with less anxiety and depression, and greater N2 and N170 to happy and fear no-go cues, respectively, were associated with greater emotional flexibility and well-being. Results suggest that pleasant and unpleasant emotions selectively enhance and disrupt components of context sensitivity, and that behavioral and ERP indices of context sensitivity predict flexibility and well-being.

Chern-Simons Modified Gravity

NASA Astrophysics Data System (ADS)

Efstratiou, P.

2013-09-01

This presentation will be based on my, undergraduate, thesis at Aristotle University of Thessoliniki with the same subject, supervised by Professor Demetrios Papadopoulos. I will first present the general mathematical formulation of the Chern-Simons (CS) modified gravity, which is split in a dynamical and a non-dynamical context, and the different physical theories which suggest this modification. Then proceed by examing the possibility that the CS theory shares solutions with General Relativity in both contexts. In the non-dynamical context I will present a new, undocumented solution as well as all the other possible solutions found to date. I will conclude by arguing that General Relativity and CS Theory share any solutions in the dynamical context.

Hydrostatic equilibrium of stars without electroneutrality constraint

NASA Astrophysics Data System (ADS)

Krivoruchenko, M. I.; Nadyozhin, D. K.; Yudin, A. V.

2018-04-01

The general solution of hydrostatic equilibrium equations for a two-component fluid of ions and electrons without a local electroneutrality constraint is found in the framework of Newtonian gravity theory. In agreement with the Poincaré theorem on analyticity and in the context of Dyson's argument, the general solution is demonstrated to possess a fixed (essential) singularity in the gravitational constant G at G =0 . The regular component of the general solution can be determined by perturbation theory in G starting from a locally neutral solution. The nonperturbative component obtained using the method of Wentzel, Kramers and Brillouin is exponentially small in the inner layers of the star and grows rapidly in the outward direction. Near the surface of the star, both components are comparable in magnitude, and their nonlinear interplay determines the properties of an electro- or ionosphere. The stellar charge varies within the limits of -0.1 to 150 C per solar mass. The properties of electro- and ionospheres are exponentially sensitive to variations of the fluid densities in the central regions of the star. The general solutions of two exactly solvable stellar models without a local electroneutrality constraint are also presented.

Dynamically Reconfigurable Approach to Multidisciplinary Problems

NASA Technical Reports Server (NTRS)

Alexandrov, Natalie M.; Lewis, Robert Michael

2003-01-01

The complexity and autonomy of the constituent disciplines and the diversity of the disciplinary data formats make the task of integrating simulations into a multidisciplinary design optimization problem extremely time-consuming and difficult. We propose a dynamically reconfigurable approach to MDO problem formulation wherein an appropriate implementation of the disciplinary information results in basic computational components that can be combined into different MDO problem formulations and solution algorithms, including hybrid strategies, with relative ease. The ability to re-use the computational components is due to the special structure of the MDO problem. We believe that this structure can and should be used to formulate and solve optimization problems in the multidisciplinary context. The present work identifies the basic computational components in several MDO problem formulations and examines the dynamically reconfigurable approach in the context of a popular class of optimization methods. We show that if the disciplinary sensitivity information is implemented in a modular fashion, the transfer of sensitivity information among the formulations under study is straightforward. This enables not only experimentation with a variety of problem formations in a research environment, but also the flexible use of formulations in a production design environment.

Time-Dependent Effects of Prazosin on the Development of Methamphetamine Conditioned Hyperactivity and Context-Specific Sensitization in Mice

PubMed Central

White, André O.; Rauhut, Anthony S.

2014-01-01

The present experiments examined the effects of prazosin, a selective α1-adrenergic receptor antagonist, on the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Mice received an injection of vehicle (distilled water) or prazosin (0.5, 1.0 or 2.0 mg/kg) 30 minutes prior to a second injection of vehicle (saline) or methamphetamine (1.0 mg/kg) during the conditioning sessions (Experiment 1). Following the conditioning sessions, mice were tested for conditioned hyperactivity and then tested for context-specific sensitization. In subsequent experiments, mice received an injection of vehicle (distilled water) or prazosin (2.0 mg/kg) immediately (Experiment 2) or 24 hours (Experiment 3) after the conditioning sessions and then tested for conditioned hyperactivity and context-specific sensitization. Prazosin dose-dependently blocked the development of methamphetamine conditioned hyperactivity and context-specific sensitization when administered prior to the methamphetamine during the conditioning phase; however nonspecific motor impairments also were observed (Experiment 1). Immediate (Experiment 2), but not the 24-hour delay (Experiment 3), post-session administration of prazosin attenuated the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Nonspecific motor impairments were not observed in these latter experiments. Collectively, these results suggest that the α1-adrenergic receptor mediates the development of methamphetamine-conditioned hyperactivity and context-specific sensitization, perhaps by altering memory consolidation and/or reconsolidation processes. PMID:24487011

Interparental Conflict and Infants’ Behavior Problems: The Mediating Role of Maternal Sensitivity

PubMed Central

Zhou, Nan; Cao, Hongjian; Leerkes, Esther M.

2016-01-01

Although the negative effect of interparental conflict on child behavior problems has been well established, few studies have examined this association during infancy. This study examined the associations between mother-reported interparental conflict and young children’s behavior problems over the first two years of their lives in a sample of 212 mothers and infants. Two aspects of maternal sensitivity, sensitivity during distressing and nondistressing contexts, were examined as possible mediators between interparental conflict and infants’ behavior problems. Results indicated that interparental conflict was associated directly with infants’ externalizing problems over time, but was associated indirectly with infants’ internalizing problems over time via compromised maternal sensitivity within distressing contexts but not through maternal sensitivity within nondistressing contexts. No significant child gender differences were found. Such findings add to a limited body of research suggesting that the early interparental relationship context is relevant for infant adjustment. The salient mediating role of maternal sensitivity within distressing contexts provides important theoretical and practical insights for future studies. PMID:28114771

Current and Future Constraints on Higgs Couplings in the Nonlinear Effective Theory

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

de Blas, Jorge; Eberhardt, Otto; Krause, Claudius

We perform a Bayesian statistical analysis of the constraints on the nonlinear Effective Theory given by the Higgs electroweak chiral Lagrangian. We obtain bounds on the effective coefficients entering in Higgs observables at the leading order, using all available Higgs-boson signal strengths from the LHC runs 1 and 2. Using a prior dependence study of the solutions, we discuss the results within the context of natural-sized Wilson coefficients. We further study the expected sensitivities to the different Wilson coefficients at various possible future colliders. Finally, we interpret our results in terms of some minimal composite Higgs models.

What do we mean by sensitivity analysis? The need for comprehensive characterization of "global" sensitivity in Earth and Environmental systems models

NASA Astrophysics Data System (ADS)

Razavi, Saman; Gupta, Hoshin V.

2015-05-01

Sensitivity analysis is an essential paradigm in Earth and Environmental Systems modeling. However, the term "sensitivity" has a clear definition, based in partial derivatives, only when specified locally around a particular point (e.g., optimal solution) in the problem space. Accordingly, no unique definition exists for "global sensitivity" across the problem space, when considering one or more model responses to different factors such as model parameters or forcings. A variety of approaches have been proposed for global sensitivity analysis, based on different philosophies and theories, and each of these formally characterizes a different "intuitive" understanding of sensitivity. These approaches focus on different properties of the model response at a fundamental level and may therefore lead to different (even conflicting) conclusions about the underlying sensitivities. Here we revisit the theoretical basis for sensitivity analysis, summarize and critically evaluate existing approaches in the literature, and demonstrate their flaws and shortcomings through conceptual examples. We also demonstrate the difficulty involved in interpreting "global" interaction effects, which may undermine the value of existing interpretive approaches. With this background, we identify several important properties of response surfaces that are associated with the understanding and interpretation of sensitivities in the context of Earth and Environmental System models. Finally, we highlight the need for a new, comprehensive framework for sensitivity analysis that effectively characterizes all of the important sensitivity-related properties of model response surfaces.

Turkish- and English-speaking children display sensitivity to perceptual context in the referring expressions they produce in speech and gesture

PubMed Central

Demir, Özlem Ece; So, Wing-Chee; Özyürek, Asli; Goldin-Meadow, Susan

2012-01-01

Speakers choose a particular expression based on many factors, including availability of the referent in the perceptual context. We examined whether, when expressing referents, monolingual English- and Turkish-speaking children: (1) are sensitive to perceptual context, (2) express this sensitivity in language-specific ways, and (3) use co-speech gestures to specify referents that are underspecified. We also explored the mechanisms underlying children’s sensitivity to perceptual context. Children described short vignettes to an experimenter under two conditions: The characters in the vignettes were present in the perceptual context (perceptual context); the characters were absent (no perceptual context). Children routinely used nouns in the no perceptual context condition, but shifted to pronouns (English-speaking children) or omitted arguments (Turkish-speaking children) in the perceptual context condition. Turkish-speaking children used underspecified referents more frequently than English-speaking children in the perceptual context condition; however, they compensated for the difference by using gesture to specify the forms. Gesture thus gives children learning structurally different languages a way to achieve comparable levels of specification while at the same time adhering to the referential expressions dictated by their language. PMID:22904588

Subtitle Synchronization across Multiple Screens and Devices

PubMed Central

Rodriguez-Alsina, Aitor; Talavera, Guillermo; Orero, Pilar; Carrabina, Jordi

2012-01-01

Ambient Intelligence is a new paradigm in which environments are sensitive and responsive to the presence of people. This is having an increasing importance in multimedia applications, which frequently rely on sensors to provide useful information to the user. In this context, multimedia applications must adapt and personalize both content and interfaces in order to reach acceptable levels of context-specific quality of service for the user, and enable the content to be available anywhere and at any time. The next step is to make content available to everybody in order to overcome the existing access barriers to content for users with specific needs, or else to adapt to different platforms, hence making content fully usable and accessible. Appropriate access to video content, for instance, is not always possible due to the technical limitations of traditional video packaging, transmission and presentation. This restricts the flexibility of subtitles and audio-descriptions to be adapted to different devices, contexts and users. New Web standards built around HTML5 enable more featured applications with better adaptation and personalization facilities, and thus would seem more suitable for accessible AmI environments. This work presents a video subtitling system that enables the customization, adaptation and synchronization of subtitles across different devices and multiple screens. The benefits of HTML5 applications for building the solution are analyzed along with their current platform support. Moreover, examples of the use of the application in three different cases are presented. Finally, the user experience of the solution is evaluated. PMID:23012513

Subtitle synchronization across multiple screens and devices.

PubMed

Rodriguez-Alsina, Aitor; Talavera, Guillermo; Orero, Pilar; Carrabina, Jordi

2012-01-01

Ambient Intelligence is a new paradigm in which environments are sensitive and responsive to the presence of people. This is having an increasing importance in multimedia applications, which frequently rely on sensors to provide useful information to the user. In this context, multimedia applications must adapt and personalize both content and interfaces in order to reach acceptable levels of context-specific quality of service for the user, and enable the content to be available anywhere and at any time. The next step is to make content available to everybody in order to overcome the existing access barriers to content for users with specific needs, or else to adapt to different platforms, hence making content fully usable and accessible. Appropriate access to video content, for instance, is not always possible due to the technical limitations of traditional video packaging, transmission and presentation. This restricts the flexibility of subtitles and audio-descriptions to be adapted to different devices, contexts and users. New Web standards built around HTML5 enable more featured applications with better adaptation and personalization facilities, and thus would seem more suitable for accessible AmI environments. This work presents a video subtitling system that enables the customization, adaptation and synchronization of subtitles across different devices and multiple screens. The benefits of HTML5 applications for building the solution are analyzed along with their current platform support. Moreover, examples of the use of the application in three different cases are presented. Finally, the user experience of the solution is evaluated.

Time-dependent effects of prazosin on the development of methamphetamine conditioned hyperactivity and context-specific sensitization in mice.

PubMed

White, André O; Rauhut, Anthony S

2014-04-15

The present experiments examined the effects of prazosin, a selective α₁-adrenergic receptor antagonist, on the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Mice received an injection of vehicle (distilled water) or prazosin (0.5, 1.0 or 2.0 mg/kg) 30 min prior to a second injection of vehicle (saline) or methamphetamine (1.0 mg/kg) during the conditioning sessions (Experiment 1). Following the conditioning sessions, mice were tested for conditioned hyperactivity and then tested for context-specific sensitization. In subsequent experiments, mice received an injection of vehicle (distilled water) or prazosin (2.0 mg/kg) immediately (Experiment 2) or 24 h (Experiment 3) after the conditioning sessions and then tested for conditioned hyperactivity and context-specific sensitization. Prazosin dose-dependently blocked the development of methamphetamine conditioned hyperactivity and context-specific sensitization when administered prior to the methamphetamine during the conditioning phase; however nonspecific motor impairments also were observed (Experiment 1). Immediate (Experiment 2), but not the 24-h delay (Experiment 3), post-session administration of prazosin attenuated the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Nonspecific motor impairments were not observed in these latter experiments. Collectively, these results suggest that the α₁-adrenergic receptor mediates the development of methamphetamine-conditioned hyperactivity and context-specific sensitization, perhaps by altering memory consolidation and/or reconsolidation processes. Copyright © 2014 Elsevier B.V. All rights reserved.

Sensitivity analysis of conservative and reactive stream transient storage models applied to field data from multiple-reach experiments

USGS Publications Warehouse

Gooseff, M.N.; Bencala, K.E.; Scott, D.T.; Runkel, R.L.; McKnight, Diane M.

2005-01-01

The transient storage model (TSM) has been widely used in studies of stream solute transport and fate, with an increasing emphasis on reactive solute transport. In this study we perform sensitivity analyses of a conservative TSM and two different reactive solute transport models (RSTM), one that includes first-order decay in the stream and the storage zone, and a second that considers sorption of a reactive solute on streambed sediments. Two previously analyzed data sets are examined with a focus on the reliability of these RSTMs in characterizing stream and storage zone solute reactions. Sensitivities of simulations to parameters within and among reaches, parameter coefficients of variation, and correlation coefficients are computed and analyzed. Our results indicate that (1) simulated values have the greatest sensitivity to parameters within the same reach, (2) simulated values are also sensitive to parameters in reaches immediately upstream and downstream (inter-reach sensitivity), (3) simulated values have decreasing sensitivity to parameters in reaches farther downstream, and (4) in-stream reactive solute data provide adequate data to resolve effective storage zone reaction parameters, given the model formulations. Simulations of reactive solutes are shown to be equally sensitive to transport parameters and effective reaction parameters of the model, evidence of the control of physical transport on reactive solute dynamics. Similar to conservative transport analysis, reactive solute simulations appear to be most sensitive to data collected during the rising and falling limb of the concentration breakthrough curve. ?? 2005 Elsevier Ltd. All rights reserved.

Constraining Assertion: An Account of Context-Sensitivity

ERIC Educational Resources Information Center

Villanueva Chigne, Eduardo

2012-01-01

Many philosophers believe that if "S" is an unambiguous, context-sensitive, declarative sentence and "p" is a proposition asserted (without conversational implicatures) by a literal utterance of "S" in a context "c," then "p" is fully determined by the linguistic meaning of "S" in…

Reduced sensitivity to context in language comprehension: A characteristic of Autism Spectrum Disorders or of poor structural language ability?

PubMed

Eberhardt, Melanie; Nadig, Aparna

2018-01-01

We present two experiments examining the universality and uniqueness of reduced context sensitivity in language processing in Autism Spectrum Disorders (ASD), as proposed by the Weak Central Coherence account (Happé & Frith, 2006, Journal of Autism and Developmental Disorders, 36(1), 25). That is, do all children with ASD exhibit decreased context sensitivity, and is this characteristic specific to ASD versus other neurodevelopmental conditions? Experiment 1, conducted in English, was a comparison of children with ASD with normal language and their typically-developing peers on a picture selection task where interpretation of sentential context was required to identify homonyms. Contrary to the predictions of Weak Central Coherence, the ASD-normal language group exhibited no difficulty on this task. Experiment 2, conducted in German, compared children with ASD with variable language abilities, typically-developing children, and a second control group of children with Language Impairment (LI) on a sentence completion task where a context sentence had to be considered to produce the continuation of an ambiguous sentence fragment. Both ASD-variable language and LI groups exhibited reduced context sensitivity and did not differ from each other. Finally, to directly test which factors contribute to reduced context sensitivity, we conducted a regression analysis for each experiment, entering nonverbal IQ, structural language ability, and autism diagnosis as predictors. For both experiments structural language ability emerged as the only significant predictor. These convergent findings demonstrate that reduced sensitivity to context in language processing is linked to low structural language rather than ASD diagnosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plastic optical fibre sensor for quality control in food industry

NASA Astrophysics Data System (ADS)

Novo, C.; Bilro, L.; Ferreira, R.; Alberto, N.; Antunes, P.; Leitão, C.; Nogueira, R.; Pinto, J. L.

2013-05-01

The present work addresses the need for new devices felt in the context of quality control, especially in the food industry. Due to the spectral dependence of the attenuation coefficient, a novel dual-parameter sensor for colour and refractive index was developed and tested. The sensor employs plastic optical fibres to measure the transmitted optical power in three measurement cells each with a different incident wavelength. The performance of the sensor was tested using several dyes at different concentrations and aqueous solutions of glycerine and ethanol. Results show that this technique allows the monitoring of refractive index and colour without cross-sensitivity.

Contextual control of instrumental actions and habits

PubMed Central

Thrailkill, Eric A.; Bouton, Mark E.

2014-01-01

After a relatively small amount of training, instrumental behavior is thought to be an action under the control of the motivational status of its goal or reinforcer. After more extended training, behavior can become habitual and insensitive to changes in reinforcer value. Recently, instrumental responding has been shown to weaken when tested outside of the training context. The present experiments compared the sensitivity of instrumental responding in rats to a context switch after training procedures that might differentially generate actions or habits. In Experiment 1, lever pressing was decremented in a new context after either short, medium, or long periods of training on either random-ratio or yoked random-interval reinforcement schedules. Experiment 2 found that more minimally-trained responding was also sensitive to a context switch. Moreover, Experiment 3 showed that when the goal-directed component of responding was removed by devaluing the reinforcer, the residual responding that remained was still sensitive to the change of context. Goal-directed responding, in contrast, transferred across contexts. Experiment 4 then found that after extensive training, a habit that was insensitive to reinforcer devaluation was still decremented by a context switch. Overall, the results suggest that a context switch primarily influences instrumental habit rather than action. In addition, even a response that has received relatively minimal training may have a habit component that is insensitive to reinforcer devaluation but sensitive to the effects of a context switch. PMID:25706547

Analytically-derived sensitivities in one-dimensional models of solute transport in porous media

USGS Publications Warehouse

Knopman, D.S.

1987-01-01

Analytically-derived sensitivities are presented for parameters in one-dimensional models of solute transport in porous media. Sensitivities were derived by direct differentiation of closed form solutions for each of the odel, and by a time integral method for two of the models. Models are based on the advection-dispersion equation and include adsorption and first-order chemical decay. Boundary conditions considered are: a constant step input of solute, constant flux input of solute, and exponentially decaying input of solute at the upstream boundary. A zero flux is assumed at the downstream boundary. Initial conditions include a constant and spatially varying distribution of solute. One model simulates the mixing of solute in an observation well from individual layers in a multilayer aquifer system. Computer programs produce output files compatible with graphics software in which sensitivities are plotted as a function of either time or space. (USGS)

A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems

PubMed Central

Choi, Donghee; Kim, Dohoon; Park, Seog

2015-01-01

Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment. PMID:26075013

Meshless methods in shape optimization of linear elastic and thermoelastic solids

NASA Astrophysics Data System (ADS)

Bobaru, Florin

This dissertation proposes a meshless approach to problems in shape optimization of elastic and thermoelastic solids. The Element-free Galerkin (EFG) method is used for this purpose. The ability of the EFG to avoid remeshing, that is normally done in a Finite Element approach to correct highly distorted meshes, is clearly demonstrated by several examples. The shape optimization example of a thermal cooling fin shows a dramatic improvement in the objective compared to a previous FEM analysis. More importantly, the new solution, displaying large shape changes contrasted to the initial design, was completely missed by the FEM analysis. The EFG formulation given here for shape optimization "uncovers" new solutions that are, apparently, unobtainable via a FEM approach. This is one of the main achievements of our work. The variational formulations for the analysis problem and for the sensitivity problems are obtained with a penalty method for imposing the displacement boundary conditions. The continuum formulation is general and this facilitates 2D and 3D with minor differences from one another. Also, transient thermoelastic problems can use the present development at each time step to solve shape optimization problems for time-dependent thermal problems. For the elasticity framework, displacement sensitivity is obtained in the EFG context. Excellent agreements with analytical solutions for some test problems are obtained. The shape optimization of a fillet is carried out in great detail, and results show significant improvement of the EFG solution over the FEM or the Boundary Element Method solutions. In our approach we avoid differentiating the complicated EFG shape functions, with respect to the shape design parameters, by using a particular discretization for sensitivity calculations. Displacement and temperature sensitivities are formulated for the shape optimization of a linear thermoelastic solid. Two important examples considered in this work, the optimization of a thermal fin and of a uniformly loaded thermoelastic beam, reveal new characteristics of the EFG method in shape optimization applications. Among other advantages of the EFG method over traditional FEM treatments of shape optimization problems, some of the most important ones are shown to be: elimination of post-processing for stress and strain recovery that directly gives more accurate results in critical positions (near the boundaries, for example) for shape optimization problems; nodes movement flexibility that permits new, better shapes (previously missed by an FEM analysis) to be discovered. Several new research directions that need further consideration are exposed.

Electrolytic lesions of the nucleus accumbens core (but not the medial shell) and the basolateral amygdala enhance context-specific locomotor sensitization to nicotine in rats.

PubMed

Kelsey, John E; Gerety, Lyle P; Guerriero, Rejean M

2009-06-01

We previously demonstrated that lesions of the nucleus accumbens (NAc) core enhanced locomotion and locomotor sensitization to repeated injections of nicotine in rats (Kelsey & Willmore, 2006). In this study, we compared the effects of separate lesions of the NAc core, NAc medial shell, and basolateral amygdala on context-specific locomotor sensitization to repeated injections of 0.4 mg/kg nicotine. Electrolytic lesions of the NAc core increased locomotion, and lesions of the core (but not the shell) and the basolateral amygdala enhanced context-specific locomotor sensitization by enhancing the development of sensitization in paired rats and decreasing expression in unpaired rats relative to sham-operated rats when challenged with an injection of 0.4 mg/kg nicotine in the locomotor chambers. These data are consistent with findings that the NAc core and the basolateral amygdala share a variety of behavioral functions and anatomical connections. The findings that lesions of these structures enhance context-specific locomotor sensitization while typically impairing other reward-related behaviors also indicate that the processes underlying locomotor sensitization and reward are not identical. Copyright (c) 2009 APA, all rights reserved.

Sensitivity-Based Guided Model Calibration

NASA Astrophysics Data System (ADS)

Semnani, M.; Asadzadeh, M.

2017-12-01

A common practice in automatic calibration of hydrologic models is applying the sensitivity analysis prior to the global optimization to reduce the number of decision variables (DVs) by identifying the most sensitive ones. This two-stage process aims to improve the optimization efficiency. However, Parameter sensitivity information can be used to enhance the ability of the optimization algorithms to find good quality solutions in a fewer number of solution evaluations. This improvement can be achieved by increasing the focus of optimization on sampling from the most sensitive parameters in each iteration. In this study, the selection process of the dynamically dimensioned search (DDS) optimization algorithm is enhanced by utilizing a sensitivity analysis method to put more emphasis on the most sensitive decision variables for perturbation. The performance of DDS with the sensitivity information is compared to the original version of DDS for different mathematical test functions and a model calibration case study. Overall, the results show that DDS with sensitivity information finds nearly the same solutions as original DDS, however, in a significantly fewer number of solution evaluations.

Autonomous indoor wayfinding for individuals with cognitive impairments

PubMed Central

2010-01-01

Background A challenge to individuals with cognitive impairments in wayfinding is how to remain oriented, recall routines, and travel in unfamiliar areas in a way relying on limited cognitive capacity. While people without disabilities often use maps or written directions as navigation tools or for remaining oriented, this cognitively-impaired population is very sensitive to issues of abstraction (e.g. icons on maps or signage) and presents the designer with a challenge to tailor navigation information specific to each user and context. Methods This paper describes an approach to providing distributed cognition support of travel guidance for persons with cognitive disabilities. A solution is proposed based on passive near-field RFID tags and scanning PDAs. A prototype is built and tested in field experiments with real subjects. The unique strength of the system is the ability to provide unique-to-the-user prompts that are triggered by context. The key to the approach is to spread the context awareness across the system, with the context being flagged by the RFID tags and the appropriate response being evoked by displaying the appropriate path guidance images indexed by the intersection of specific end-user and context ID embedded in RFID tags. Results We found that passive RFIDs generally served as good context for triggering navigation prompts, although individual differences in effectiveness varied. The results of controlled experiments provided more evidence with regard to applicabilities of the proposed autonomous indoor wayfinding method. Conclusions Our findings suggest that the ability to adapt indoor wayfinding devices for appropriate timing of directions and standing orientation will be particularly important. PMID:20840786

Real-time inverse kinematics and inverse dynamics for lower limb applications using OpenSim

PubMed Central

Modenese, L.; Lloyd, D.G.

2017-01-01

Real-time estimation of joint angles and moments can be used for rapid evaluation in clinical, sport, and rehabilitation contexts. However, real-time calculation of kinematics and kinetics is currently based on approximate solutions or generic anatomical models. We present a real-time system based on OpenSim solving inverse kinematics and dynamics without simplifications at 2000 frame per seconds with less than 31.5ms of delay. We describe the software architecture, sensitivity analyses to minimise delays and errors, and compare offline and real-time results. This system has the potential to strongly impact current rehabilitation practices enabling the use of personalised musculoskeletal models in real-time. PMID:27723992

Autonomous Information Unit: Why Making Data Smart Can also Make Data Secured?

NASA Technical Reports Server (NTRS)

Chow, Edward T.

2006-01-01

In this paper, we introduce a new fine-grain distributed information protection mechanism which can self-protect, self-discover, self-organize, and self-manage. In our approach, we decompose data into smaller pieces and provide individualized protection. We also provide a policy control mechanism to allow 'smart' access control and context based re-assembly of the decomposed data. By combining smart policy with individually protected data, we are able to provide better protection of sensitive information and achieve more flexible access during emergency conditions. As a result, this new fine-grain protection mechanism can enable us to achieve better solutions for problems such as distributed information protection and identity theft.

Real-time inverse kinematics and inverse dynamics for lower limb applications using OpenSim.

PubMed

Pizzolato, C; Reggiani, M; Modenese, L; Lloyd, D G

2017-03-01

Real-time estimation of joint angles and moments can be used for rapid evaluation in clinical, sport, and rehabilitation contexts. However, real-time calculation of kinematics and kinetics is currently based on approximate solutions or generic anatomical models. We present a real-time system based on OpenSim solving inverse kinematics and dynamics without simplifications at 2000 frame per seconds with less than 31.5 ms of delay. We describe the software architecture, sensitivity analyses to minimise delays and errors, and compare offline and real-time results. This system has the potential to strongly impact current rehabilitation practices enabling the use of personalised musculoskeletal models in real-time.

Creativity as a Key Driver for Designing Context Sensitive Health Informatics.

PubMed

Zhou, Chunfang; Nøhr, Christian

2017-01-01

In order to face the increasing challenges of complexity and uncertainty in practice of health care, this paper aims to discuss how creativity can contribute to design new technologies in health informatics systems. It will firstly introduce the background highlighting creativity as a missing element in recent studies on context sensitive health informatics. Secondly, the concept of creativity and its relationship with activities of technology design will be discussed from a socio-culture perspective. This will be thirdly followed by understanding the roles of creativity in designing new health informatics technologies for meeting needs of high context sensitivity. Finally, a series of potential strategies will be suggested to improve creativity among technology designers working in healthcare industries. Briefly, this paper innovatively bridges two areas studies on creativity and context sensitive health informatics by issues of technology design that also indicates its important significances for future research.

Classification of the micro and nanoparticles and biological agents by neural network analysis of the parameters of optical resonance of whispering gallery mode in dielectric microspheres

NASA Astrophysics Data System (ADS)

Saetchnikov, Vladimir A.; Tcherniavskaia, Elina A.; Schweiger, Gustav; Ostendorf, Andreas

2011-07-01

A novel technique for the label-free analysis of micro and nanoparticles including biomolecules using optical micro cavity resonance of whispering-gallery-type modes is being developed. Various schemes of the method using both standard and specially produced microspheres have been investigated to make further development for microbial application. It was demonstrated that optical resonance under optimal geometry could be detected under the laser power of less 1 microwatt. The sensitivity of developed schemes has been tested by monitoring the spectral shift of the whispering gallery modes. Water solutions of ethanol, ascorbic acid, blood phantoms including albumin and HCl, glucose, biotin, biomarker like C reactive protein so as bacteria and virus phantoms (gels of silica micro and nanoparticles) have been used. Structure of resonance spectra of the solutions was a specific subject of investigation. Probabilistic neural network classifier for biological agents and micro/nano particles classification has been developed. Several parameters of resonance spectra as spectral shift, broadening, diffuseness and others have been used as input parameters to develop a network classifier for micro and nanoparticles and biological agents in solution. Classification probability of approximately 98% for probes under investigation have been achieved. Developed approach have been demonstrated to be a promising technology platform for sensitive, lab-on-chip type sensor which can be used for development of diagnostic tools for different biological molecules, e.g. proteins, oligonucleotides, oligosaccharides, lipids, small molecules, viral particles, cells as well as in different experimental contexts e.g. proteomics, genomics, drug discovery, and membrane studies.

Context management platform for tourism applications.

PubMed

Buján, David; Martín, David; Torices, Ortzi; López-de-Ipiña, Diego; Lamsfus, Carlos; Abaitua, Joseba; Alzua-Sorzabal, Aurkene

2013-06-24

The notion of context has been widely studied and there are several authors that have proposed different definitions of context. However, context has not been widely studied in the framework of human mobility and the notion of context has been imported directly from other computing fields without specifically addressing the tourism domain requirements. In order to store and manage context information a context data model and a context management platform are needed. Ontologies have been widely used in context modelling, but many of them are designed to be applied in general ubiquitous computing environments, do not contain specific concepts related to the tourism domain or some approaches do not contain enough concepts to represent context information related to the visitor on the move. That is why we propose a new approach to provide a better solution to model context data in tourism environments, adding more value to our solution reusing data about tourist resources from an Open Data repository and publishing it as Linked Data. We also propose the architecture for a context information management platform based on this context data model.

Context Management Platform for Tourism Applications

PubMed Central

Buján, David; Martín, David; Torices, Ortzi; López-de-Ipiña, Diego; Lamsfus, Carlos; Abaitua, Joseba; Alzua-Sorzabal, Aurkene

2013-01-01

The notion of context has been widely studied and there are several authors that have proposed different definitions of context. However, context has not been widely studied in the framework of human mobility and the notion of context has been imported directly from other computing fields without specifically addressing the tourism domain requirements. In order to store and manage context information a context data model and a context management platform are needed. Ontologies have been widely used in context modelling, but many of them are designed to be applied in general ubiquitous computing environments, do not contain specific concepts related to the tourism domain or some approaches do not contain enough concepts to represent context information related to the visitor on the move. That is why we propose a new approach to provide a better solution to model context data in tourism environments, adding more value to our solution reusing data about tourist resources from an Open Data repository and publishing it as Linked Data. We also propose the architecture for a context information management platform based on this context data model. PMID:23797739

Maternal sensitivity and adrenocortical functioning across infancy and toddlerhood: Physiological adaptation to context?

PubMed Central

BERRY, DANIEL; BLAIR, CLANCY; WILLOUGHBY, MICHAEL; GRANGER, DOUGLAS A.; MILLS-KOONCE, W. ROGER

2018-01-01

Theory suggests that early experiences may calibrate the “threshold activity” of the hypothalamus–pituitary–adrenal axis in childhood. Particularly challenging or particularly supportive environments are posited to manifest in heightened physiological sensitivity to context. Using longitudinal data from the Family Life Project (N = 1,292), we tested whether links between maternal sensitivity and hypothalamus–pituitary–adrenal axis activity aligned with these predictions. Specifically, we tested whether the magnitude of the within-person relation between maternal sensitivity and children’s cortisol levels, a proxy for physiological sensitivity to context, was especially pronounced for children who typically experienced particularly low or high levels of maternal sensitivity over time. Our results were consistent with these hypotheses. Between children, lower levels of mean maternal sensitivity (7–24 months) were associated with higher mean cortisol levels across this period (measured as a basal sample collected at each visit). However, the magnitude and direction of the within-person relation was contingent on children’s average levels of maternal sensitivity over time. Increases in maternal sensitivity were associated with contemporaneous cortisol decreases for children with typically low-sensitive mothers, whereas sensitivity increases were associated with cortisol increases for children with typically high-sensitive mothers. No within-child effects were evident at moderate levels of maternal sensitivity. PMID:27065311

Small-inclusion asymptotic of misfit functionals for inverse problems in acoustics

NASA Astrophysics Data System (ADS)

Guzina, Bojan B.; Bonnet, Marc

2006-10-01

The aim of this study is an extension and employment of the concept of topological derivative as it pertains to the nucleation of infinitesimal inclusions in a reference (i.e. background) acoustic medium. The developments are motivated by the need to develop a preliminary indicator functional that would aid the solution of inverse scattering problems in terms of a rational initial 'guess' about the geometry and material characteristics of a hidden (finite) obstacle; an information that is often required by iterative minimization algorithms. To this end the customary definition of topological derivative, which quantifies the sensitivity of a given cost functional with respect to the creation of an infinitesimal hole, is adapted to permit the nucleation of a dissimilar acoustic medium. On employing the Green's function for the background domain, computation of topological sensitivity for the three-dimensional Helmholtz equation is reduced to the solution of a reference, Laplace transmission problem. Explicit formulae are given for the nucleating inclusions of spherical and ellipsoidal shapes. For generality the developments are also presented in an alternative, adjoint-field setting that permits nucleation of inclusions in an infinite, semi-infinite or finite background medium. Through numerical examples, it is shown that the featured topological sensitivity could be used, in the context of inverse scattering, as an effective obstacle indicator through an assembly of sampling points where it attains pronounced negative values. On varying a material characteristic (density) of the nucleating obstacle, it is also shown that the proposed methodology can be used as a preparatory tool for both geometric and material identification.

Action-FRET of a Gaseous Protein

NASA Astrophysics Data System (ADS)

Daly, Steven; Knight, Geoffrey; Halim, Mohamed Abdul; Kulesza, Alexander; Choi, Chang Min; Chirot, Fabien; MacAleese, Luke; Antoine, Rodolphe; Dugourd, Philippe

2017-01-01

Mass spectrometry is an extremely powerful technique for analysis of biological molecules, in particular proteins. One aspect that has been contentious is how much native solution-phase structure is preserved upon transposition to the gas phase by soft ionization methods such as electrospray ionization. To address this question—and thus further develop mass spectrometry as a tool for structural biology—structure-sensitive techniques must be developed to probe the gas-phase conformations of proteins. Here, we report Förster resonance energy transfer (FRET) measurements on a ubiquitin mutant using specific photofragmentation as a reporter of the FRET efficiency. The FRET data is interpreted in the context of circular dichroism, molecular dynamics simulation, and ion mobility data. Both the dependence of the FRET efficiency on the charge state—where a systematic decrease is observed—and on methanol concentration are considered. In the latter case, a decrease in FRET efficiency with methanol concentration is taken as evidence that the conformational ensemble of gaseous protein cations retains a memory of the solution phase conformational ensemble upon electrospray ionization.

Sensitivity, Specificity, and Predictive Values: Foundations, Pliabilities, and Pitfalls in Research and Practice.

PubMed

Trevethan, Robert

2017-01-01

Within the context of screening tests, it is important to avoid misconceptions about sensitivity, specificity, and predictive values. In this article, therefore, foundations are first established concerning these metrics along with the first of several aspects of pliability that should be recognized in relation to those metrics. Clarification is then provided about the definitions of sensitivity, specificity, and predictive values and why researchers and clinicians can misunderstand and misrepresent them. Arguments are made that sensitivity and specificity should usually be applied only in the context of describing a screening test's attributes relative to a reference standard; that predictive values are more appropriate and informative in actual screening contexts, but that sensitivity and specificity can be used for screening decisions about individual people if they are extremely high; that predictive values need not always be high and might be used to advantage by adjusting the sensitivity and specificity of screening tests; that, in screening contexts, researchers should provide information about all four metrics and how they were derived; and that, where necessary, consumers of health research should have the skills to interpret those metrics effectively for maximum benefit to clients and the healthcare system.

Sensitivity, Specificity, and Predictive Values: Foundations, Pliabilities, and Pitfalls in Research and Practice

PubMed Central

Trevethan, Robert

2017-01-01

Within the context of screening tests, it is important to avoid misconceptions about sensitivity, specificity, and predictive values. In this article, therefore, foundations are first established concerning these metrics along with the first of several aspects of pliability that should be recognized in relation to those metrics. Clarification is then provided about the definitions of sensitivity, specificity, and predictive values and why researchers and clinicians can misunderstand and misrepresent them. Arguments are made that sensitivity and specificity should usually be applied only in the context of describing a screening test’s attributes relative to a reference standard; that predictive values are more appropriate and informative in actual screening contexts, but that sensitivity and specificity can be used for screening decisions about individual people if they are extremely high; that predictive values need not always be high and might be used to advantage by adjusting the sensitivity and specificity of screening tests; that, in screening contexts, researchers should provide information about all four metrics and how they were derived; and that, where necessary, consumers of health research should have the skills to interpret those metrics effectively for maximum benefit to clients and the healthcare system. PMID:29209603

Are orchids left and dandelions right? Frontal brain activation asymmetry and its sensitivity to developmental context.

PubMed

Fortier, Paz; Van Lieshout, Ryan J; Waxman, Jordana A; Boyle, Michael H; Saigal, Saroj; Schmidt, Louis A

2014-08-01

To clarify long-standing conceptual and empirical inconsistencies in models describing the relation between frontal brain asymmetry and emotion, we tested a theory of biological sensitivity to context. We examined whether asymmetry of alpha activation in frontal brain regions, as measured by resting electroencephalography, is sensitive to early developmental contexts. Specifically, we investigated whether frontal asymmetry moderates the association between birth weight and adult outcomes. Adults with left frontal asymmetry (LFA) who were born at extremely low birth weight exhibited high levels of attention problems and withdrawn behaviors in their 30s, whereas normal-birth-weight adults with LFA had low levels of these problem behaviors. Adults with right frontal asymmetry (RFA) displayed a relatively moderate amount of problem behavior regardless of birth weight. Our findings suggest that LFA is associated with sensitivity to developmental context and may help explain why LFA is associated with both positive and negative outcomes, whereas RFA seems to be associated with a more canalized process in some contexts. © The Author(s) 2014.

Variation in Optoelectronic Properties of Azo Dye-Sensitized TiO 2 Semiconductor Interfaces with Different Adsorption Anchors: Carboxylate, Sulfonate, Hydroxyl and Pyridyl Groups

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

Zhang, Lei; Cole, Jacqueline M.; Dai, Chencheng

2014-05-28

The optoelectronic properties of four azo dye-sensitized TiO2 interfaces are systematically studied as a function of a changing dye anchoring group: carboxylate, sulfonate, hydroxyl, and pyridyl. The variation in optoelectronic properties of the free dyes and those in dye/TiO 2 nanocomposites are studied both experimentally and computationally, in the context of prospective dye-sensitized solar cell (DSSC) applications. Experimental UV/vis absorption spectroscopy, cyclic voltammetry, and DSSC device performance testing reveal a strong dependence on the nature of the anchor of the optoelectronic properties of these dyes, both in solution and as dye/TiO2 nanocomposites. First-principles calculations on both an isolated dye/TiO2 clustermore » model (using localized basis sets) and each dye modeled onto the surface of a 2D periodic TiO2 nanostructure (using plane wave basis sets) are presented. Detailed examination of these experimental and computational results, in terms of light harvesting, electron conversion and photovoltaic device performance characteristics, indicates that carboxylate is the best anchoring group, and hydroxyl is the worst, whereas sulfonate and pyridyl groups exhibit competing potential. Different sensitization solvents are found to affect critically the extent of dye adsorption achieved in the dye-sensitization of the TiO2 semiconductor, especially where the anchor is a pyridyl group.« less

Context sensitive design : thinking beyond the pavement : documentation of workshop development and training.

DOT National Transportation Integrated Search

2005-05-01

This report documents the development and presentation of the workshop titled Thinking Beyond the Pavement A Workshop on Context Sensitive Design. Work began on the workshop development in 1998 after the Kentucky Transportation Cabinet was ...

Electronic Health Records: An Enhanced Security Paradigm to Preserve Patient's Privacy

NASA Astrophysics Data System (ADS)

Slamanig, Daniel; Stingl, Christian

In recent years, demographic change and increasing treatment costs demand the adoption of more cost efficient, highly qualitative and integrated health care processes. The rapid growth and availability of the Internet facilitate the development of eHealth services and especially of electronic health records (EHRs) which are promising solutions to meet the aforementioned requirements. Considering actual web-based EHR systems, patient-centric and patient moderated approaches are widely deployed. Besides, there is an emerging market of so called personal health record platforms, e.g. Google Health. Both concepts provide a central and web-based access to highly sensitive medical data. Additionally, the fact that these systems may be hosted by not fully trustworthy providers necessitates to thoroughly consider privacy issues. In this paper we define security and privacy objectives that play an important role in context of web-based EHRs. Furthermore, we discuss deployed solutions as well as concepts proposed in the literature with respect to this objectives and point out several weaknesses. Finally, we introduce a system which overcomes the drawbacks of existing solutions by considering an holistic approach to preserve patient's privacy and discuss the applied methods.

Reducing the ecological impact of field research.

PubMed

Bezanson, Michelle; Stowe, Rochelle; Watts, Sean M

2013-01-01

Researchers and students at biological field stations, especially in remote areas, are subject to leaving "footprints," as we conduct research, work, and live in sensitive ecosystems. These footprints include travel, personal trash and waste, and field equipment (e.g. flagging, tree markers, plot markers, trail markers, monitoring devices, etc.). In this commentary, we argue that the field of primatology's commitment to minimum impact research should be more explicitly and visibly integrated into our ethical protocols with regard to field research and instruction in sensitive environments. We review current ethical codes and potential solutions to reducing our "researcher footprints" while conducting fieldwork. Using Costa Rica as an example, we address how sustainable fieldwork differs among varying cultural contexts and argue that researchers should be made responsible and accountable for how our presence, research, and teaching might impact the environment. We conclude by recommending a set of guidelines to be added to ethical protocols regarding research design, station policies, and the conduct of research and teaching in the field. © 2012 Wiley Periodicals, Inc.

A multifaceted FISH approach to study endogenous RNAs and DNAs in native nuclear and cell structures.

PubMed

Byron, Meg; Hall, Lisa L; Lawrence, Jeanne B

2013-01-01

Fluorescence in situ hybridization (FISH) is not a singular technique, but a battery of powerful and versatile tools for examining the distribution of endogenous genes and RNAs in precise context with each other and in relation to specific proteins or cell structures. This unit offers the details of highly sensitive and successful protocols that were initially developed largely in our lab and honed over a number of years. Our emphasis is on analysis of nuclear RNAs and DNA to address specific biological questions about nuclear structure, pre-mRNA metabolism, or the role of noncoding RNAs; however, cytoplasmic RNA detection is also discussed. Multifaceted molecular cytological approaches bring precise resolution and sensitive multicolor detection to illuminate the organization and functional roles of endogenous genes and their RNAs within the native structure of fixed cells. Solutions to several common technical pitfalls are discussed, as are cautions regarding the judicious use of digital imaging and the rigors of analyzing and interpreting complex molecular cytological results.

Evaluation of commercial skin prick test solutions for selected occupational allergens.

PubMed

van Kampen, V; de Blay, F; Folletti, I; Kobierski, P; Moscato, G; Olivieri, M; Quirce, S; Sastre, J; Walusiak-Skorupa, J; Kotschy-Lang, N; Müsken, H; Mahler, V; Schliemann, S; Ochmann, U; Sültz, J; Worm, M; Sander, I; Zahradnik, E; Brüning, T; Merget, R; Raulf-Heimsoth, M

2013-01-01

Skin prick testing (SPT) is an important step in the diagnosis of IgE-mediated occupational allergic diseases. The outcome of SPT is related to the quality of allergen extracts. Thus, the aim of the study was to assess different commercially available SPT solutions for selected occupational allergens. SPT was performed in 116 bakers, 47 farmers and 33 subjects exposed to natural rubber latex (NRL), all with work-related allergic symptoms. The SPT solutions from different manufacturers (n = 3-5) for wheat flour, rye flour, soy, cow hair/dander, storage mites (Tyrophagus putrescentiae, Lepidoglyphus destructor, Acarus siro) and NRL were analysed with respect to their protein and antigen contents. SPT was carried out in 16 allergy centres in six European countries using standardized procedures. Specific IgE values were used as the gold standard to calculate the sensitivity and specificity of SPT solutions. The optimal cut-point for each SPT solution was determined by Youden Index. Protein and antigen contents and patterns of the SPT solutions varied remarkably depending on the manufacturer. While SPT solutions for wheat flour and soy reached overall low sensitivities, sensitivities of other tested SPT solutions depended on the manufacturer. As a rule, solutions with higher protein and antigen content showed higher sensitivities and test efficiencies. There is a wide variability of SPT solutions for occupational allergens, and the sensitivity of several solutions is low. Thus, improvement and standardization of SPT solutions for occupational allergens is essential. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Sensitive bridge circuit measures conductance of low-conductivity electrolyte solutions

NASA Technical Reports Server (NTRS)

Schmidt, K.

1967-01-01

Compact bridge circuit measures sensitive and accurate conductance of low-conductivity electrolyte solutions. The bridge utilizes a phase sensitive detector to obtain a linear deflection of the null indicator relative to the measured conductance.

Benefits and Financial Impacts of Adopting Technology in Learning

ERIC Educational Resources Information Center

Grenman, Katri; Isomursu, Minna; Federley, Maija; Seisto, Anu

2013-01-01

This paper summarizes the results of an analysis of the impacts of adopting information and communication technology (ICT) solutions in a learning context. The analysis is based on a literature survey of articles reporting research cases studying the impact of adopting ICT based solutions in various learning contexts. The subject has been reviewed…

Informed Conjecturing of Solutions for Differential Equations in a Modeling Context

ERIC Educational Resources Information Center

Winkel, Brian

2015-01-01

We examine two differential equations. (i) first-order exponential growth or decay; and (ii) second order, linear, constant coefficient differential equations, and show the advantage of learning differential equations in a modeling context for informed conjectures of their solution. We follow with a discussion of the complete analysis afforded by…

Visual context processing deficits in schizophrenia: effects of deafness and disorganization.

PubMed

Horton, Heather K; Silverstein, Steven M

2011-07-01

Visual illusions allow for strong tests of perceptual functioning. Perceptual impairments can produce superior task performance on certain tasks (i.e., more veridical perception), thereby avoiding generalized deficit confounds while tapping mechanisms that are largely outside of conscious control. Using a task based on the Ebbinghaus illusion, a perceptual phenomenon where the perceived size of a central target object is affected by the size of surrounding inducers, we tested hypotheses related to visual integration in deaf (n = 31) and hearing (n = 34) patients with schizophrenia. In past studies, psychiatrically healthy samples displayed increased visual integration relative to schizophrenia samples and thus were less able to correctly judge target sizes. Deafness, and especially the use of sign language, leads to heightened sensitivity to peripheral visual cues and increased sensitivity to visual context. Therefore, relative to hearing subjects, deaf subjects were expected to display increased context sensitivity (ie, a more normal illusion effect as evidenced by a decreased ability to correctly judge central target sizes). Confirming the hypothesis, deaf signers were significantly more sensitive to the illusion than nonsigning hearing patients. Moreover, an earlier age of sign language acquisition, higher levels of linguistic ability, and shorter illness duration were significantly related to increased context sensitivity. As predicted, disorganization was associated with reduced context sensitivity for all subjects. The primary implications of these data are that perceptual organization impairment in schizophrenia is plastic and that it is related to a broader failure in coordinating cognitive activity.

Formal language theory: refining the Chomsky hierarchy

PubMed Central

Jäger, Gerhard; Rogers, James

2012-01-01

The first part of this article gives a brief overview of the four levels of the Chomsky hierarchy, with a special emphasis on context-free and regular languages. It then recapitulates the arguments why neither regular nor context-free grammar is sufficiently expressive to capture all phenomena in the natural language syntax. In the second part, two refinements of the Chomsky hierarchy are reviewed, which are both relevant to the extant research in cognitive science: the mildly context-sensitive languages (which are located between context-free and context-sensitive languages), and the sub-regular hierarchy (which distinguishes several levels of complexity within the class of regular languages). PMID:22688632

Formal language theory: refining the Chomsky hierarchy.

PubMed

Jäger, Gerhard; Rogers, James

2012-07-19

The first part of this article gives a brief overview of the four levels of the Chomsky hierarchy, with a special emphasis on context-free and regular languages. It then recapitulates the arguments why neither regular nor context-free grammar is sufficiently expressive to capture all phenomena in the natural language syntax. In the second part, two refinements of the Chomsky hierarchy are reviewed, which are both relevant to the extant research in cognitive science: the mildly context-sensitive languages (which are located between context-free and context-sensitive languages), and the sub-regular hierarchy (which distinguishes several levels of complexity within the class of regular languages).

Situation resolution with context-sensitive fuzzy relations

NASA Astrophysics Data System (ADS)

Jakobson, Gabriel; Buford, John; Lewis, Lundy

2009-05-01

Context plays a significant role in situation resolution by intelligent agents (human or machine) by affecting how the situations are recognized, interpreted, acted upon or predicted. Many definitions and formalisms for the notion of context have emerged in various research fields including psychology, economics and computer science (computational linguistics, data management, control theory, artificial intelligence and others). In this paper we examine the role of context in situation management, particularly how to resolve situations that are described by using fuzzy (inexact) relations among their components. We propose a language for describing context sensitive inexact constraints and an algorithm for interpreting relations using inexact (fuzzy) computations.

Space-time adaptive solution of inverse problems with the discrete adjoint method

NASA Astrophysics Data System (ADS)

Alexe, Mihai; Sandu, Adrian

2014-08-01

This paper develops a framework for the construction and analysis of discrete adjoint sensitivities in the context of time dependent, adaptive grid, adaptive step models. Discrete adjoints are attractive in practice since they can be generated with low effort using automatic differentiation. However, this approach brings several important challenges. The space-time adjoint of the forward numerical scheme may be inconsistent with the continuous adjoint equations. A reduction in accuracy of the discrete adjoint sensitivities may appear due to the inter-grid transfer operators. Moreover, the optimization algorithm may need to accommodate state and gradient vectors whose dimensions change between iterations. This work shows that several of these potential issues can be avoided through a multi-level optimization strategy using discontinuous Galerkin (DG) hp-adaptive discretizations paired with Runge-Kutta (RK) time integration. We extend the concept of dual (adjoint) consistency to space-time RK-DG discretizations, which are then shown to be well suited for the adaptive solution of time-dependent inverse problems. Furthermore, we prove that DG mesh transfer operators on general meshes are also dual consistent. This allows the simultaneous derivation of the discrete adjoint for both the numerical solver and the mesh transfer logic with an automatic code generation mechanism such as algorithmic differentiation (AD), potentially speeding up development of large-scale simulation codes. The theoretical analysis is supported by numerical results reported for a two-dimensional non-stationary inverse problem.

The Sociocultural Contexts of Learning in the Workplace.

ERIC Educational Resources Information Center

Bierema, Laura L.

2002-01-01

Outlines demographic dimensions of the work force: aging, gender, race, sexual orientation, immigration, language, religion. Suggests a workplace pedagogy that is sensitive to sociocultural context and includes the concept of workplace learning as a lifelong process, socioculturally sensitive policies, equal opportunity development, and diversity…

Engineered Context-Sensitive Agonism: Tissue-Selective Drug Signaling through a G Protein-Coupled Receptor.

PubMed

Seemann, Wiebke K; Wenzel, Daniela; Schrage, Ramona; Etscheid, Justine; Bödefeld, Theresa; Bartol, Anna; Warnken, Mareille; Sasse, Philipp; Klöckner, Jessica; Holzgrabe, Ulrike; DeAmici, Marco; Schlicker, Eberhard; Racké, Kurt; Kostenis, Evi; Meyer, Rainer; Fleischmann, Bernd K; Mohr, Klaus

2017-02-01

Drug discovery strives for selective ligands to achieve targeted modulation of tissue function. Here we introduce engineered context-sensitive agonism as a postreceptor mechanism for tissue-selective drug action through a G protein-coupled receptor. Acetylcholine M 2 -receptor activation is known to mediate, among other actions, potentially dangerous slowing of the heart rate. This unwanted side effect is one of the main reasons that limit clinical application of muscarinic agonists. Herein we show that dualsteric (orthosteric/allosteric) agonists induce less cardiac depression ex vivo and in vivo than conventional full agonists. Exploration of the underlying mechanism in living cells employing cellular dynamic mass redistribution identified context-sensitive agonism of these dualsteric agonists. They translate elevation of intracellular cAMP into a switch from full to partial agonism. Designed context-sensitive agonism opens an avenue toward postreceptor pharmacologic selectivity, which even works in target tissues operated by the same subtype of pharmacologic receptor. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Sensitivity method for integrated structure/active control law design

NASA Technical Reports Server (NTRS)

Gilbert, Michael G.

1987-01-01

The development is described of an integrated structure/active control law design methodology for aeroelastic aircraft applications. A short motivating introduction to aeroservoelasticity is given along with the need for integrated structures/controls design algorithms. Three alternative approaches to development of an integrated design method are briefly discussed with regards to complexity, coordination and tradeoff strategies, and the nature of the resulting solutions. This leads to the formulation of the proposed approach which is based on the concepts of sensitivity of optimum solutions and multi-level decompositions. The concept of sensitivity of optimum is explained in more detail and compared with traditional sensitivity concepts of classical control theory. The analytical sensitivity expressions for the solution of the linear, quadratic cost, Gaussian (LQG) control problem are summarized in terms of the linear regulator solution and the Kalman Filter solution. Numerical results for a state space aeroelastic model of the DAST ARW-II vehicle are given, showing the changes in aircraft responses to variations of a structural parameter, in this case first wing bending natural frequency.

Context-specific modulation of cocaine-induced locomotor sensitization and ERK and CREB phosphorylation in rat nucleus accumbens

PubMed Central

Marin, Marcelo T.; Berkow, Alexander; Golden, Sam A.; Koya, Eisuke; Planeta, Cleopatra S.; Hope, Bruce T.

2009-01-01

Learned associations are hypothesized to develop between drug effects and contextual stimuli during repeated drug administration to produce context-specific sensitization that is expressed only in the drug-associated environment and not in a non-drug paired environment. Neuroadaptations that mediate such context-specific behavior are largely unknown. We investigated context-specific modulation of CREB phosphorylation and four upstream kinases in nucleus accumbens that phosphorylate CREB, including ERK, PKA, CaMKII and IV. Rats received seven once daily injections of cocaine or saline in one of two distinct environments outside their home cages. Seven days later, test injections of cocaine or saline were administered in either the Paired or the Non-paired environment. CREB and ERK phosphorylation were assessed with immunohistochemistry while phosphorylation of the remaining kinases, as well as CREB and ERK, were assessed by Western blotting. Repeated cocaine administration produced context-specific sensitized locomotor responses accompanied by context-specific enhancement of the number of cocaine-induced phosphoCREB and phosphoERK immunoreactive nuclei in a minority of neurons. In contrast, CREB and CaMKIV phosphorylation in nucleus accumbens homogenates were decreased by cocaine test injections. We have recently shown that a small number of cocaine-activated accumbens neurons mediate the learned association between cocaine effects and the drug administration environment to produce context-specific sensitization. The corresponding cocaine and context-specific phosphorylation of ERK and CREB in cocaine-activated accumbens neurons in the present study suggests that this signal transduction pathway is also selectively activated in the same set of accumbens neurons. PMID:19912338

Adolescent Neurobiological Susceptibility to Social Context

PubMed Central

Schriber, Roberta A.; Guyer, Amanda E.

2016-01-01

Adolescence has been characterized as a period of heightened sensitivity to social contexts. However, adolescents vary in how their social contexts affect them. According to neurobiological susceptibility models, endogenous, biological factors confer some individuals, relative to others, with greater susceptibility to environmental influences, whereby more susceptible individuals fare the best or worst of all individuals, depending on the environment they encounter (e.g., high vs. low parental warmth). Until recently, research guided by these theoretical frameworks has not incorporated direct measures of brain structure or function to index this sensitivity. Drawing on prevailing models of adolescent neurodevelopment and a growing number of neuroimaging studies on the interrelations among social contexts, the brain, and developmental outcomes, we review research that supports the idea of adolescent neurobiological susceptibility to social context for understanding why and how adolescents differ in development and well-being. We propose that adolescent development is shaped in part by brain-based individual differences in sensitivity to social contexts – be they positive or negative – such as those created through relationships with parents/caregivers and peers. As such, we recommend that future research measure brain function and structure to operationalize susceptibility factors that moderate the influence of social contexts on developmental outcomes. PMID:26773514

Children’s Sensitivity to the Knowledge Expressed in Pedagogical and Non-Pedagogical Contexts

PubMed Central

Gelman, Susan A.; Ware, Elizabeth A.; Manczak, Erika M.; Graham, Susan A.

2013-01-01

The present studies test two hypotheses: (1) that pedagogical contexts especially convey generic information (Csibra & Gergely, 2009), and (2) that young children are sensitive to this aspect of pedagogy. We examined generic language (e.g., “Elephants live in Africa”) in three studies, focusing on: informational versus narrative children’s books (Study 1), the language of 6-year-old children and adults assuming either a pedagogical (teacher) or non-pedagogical (friend) role (Study 2), and the language of 5-year-old children and adults speaking to either an ignorant alien (pedagogical context) or a peer (non-pedagogical context; Study 3). Results suggest that generics are more frequent in informational than narrative texts. Furthermore, both adults and young children provide more generic language in pedagogical contexts and when assuming a pedagogical role. Together, the studies demonstrate that pedagogical contexts are distinctive in conveying generic information, and that children are sensitive to this aspect of the language input. We suggest that generic knowledge is more useful in making predictions about the future, and thus more highly valued during instruction. PMID:22468565

Further comments on sensitivities, parameter estimation, and sampling design in one-dimensional analysis of solute transport in porous media

USGS Publications Warehouse

Knopman, Debra S.; Voss, Clifford I.

1988-01-01

Sensitivities of solute concentration to parameters associated with first-order chemical decay, boundary conditions, initial conditions, and multilayer transport are examined in one-dimensional analytical models of transient solute transport in porous media. A sensitivity is a change in solute concentration resulting from a change in a model parameter. Sensitivity analysis is important because minimum information required in regression on chemical data for the estimation of model parameters by regression is expressed in terms of sensitivities. Nonlinear regression models of solute transport were tested on sets of noiseless observations from known models that exceeded the minimum sensitivity information requirements. Results demonstrate that the regression models consistently converged to the correct parameters when the initial sets of parameter values substantially deviated from the correct parameters. On the basis of the sensitivity analysis, several statements may be made about design of sampling for parameter estimation for the models examined: (1) estimation of parameters associated with solute transport in the individual layers of a multilayer system is possible even when solute concentrations in the individual layers are mixed in an observation well; (2) when estimating parameters in a decaying upstream boundary condition, observations are best made late in the passage of the front near a time chosen by adding the inverse of an hypothesized value of the source decay parameter to the estimated mean travel time at a given downstream location; (3) estimation of a first-order chemical decay parameter requires observations to be made late in the passage of the front, preferably near a location corresponding to a travel time of √2 times the half-life of the solute; and (4) estimation of a parameter relating to spatial variability in an initial condition requires observations to be made early in time relative to passage of the solute front.

Experimental study on the influence of slickwater on shale permeability

NASA Astrophysics Data System (ADS)

Liu, Zhonghua; Bai, Baojun; Zhang, Zheyu; Tang, Jing; Zeng, Shunpeng; Li, Xiaogang

2018-02-01

There are two diametrically opposite views of the influence of slickwater on shale permeability among scholars at home and abroad. We used the shale outcrops rock samples from the Lower Silurian Longmaxi Formation in Sichuan Basin. The permeability of these dry samples before and after immersion in different solution systems were tested by pulse attenuation method. The experimental results show that the impregnation of different slickwater components and standard salt solution can promote the increase of the permeability of shale samples. The stress sensitivity of shale samples after liquid immersion is medium weak to weak. The sample stress sensitivity is weak after soaked by the synergist solution and Drag reducing agent solution, and the sensitivity of the sample stress is medium weak after immersed by the standard saline solution, defoamer solution and antiswelling solution; The Ki/K0 of the shale sample after liquid immersion on σi/σ0 is consistent with the exponential stress sensitive evaluation model. With the increase of soaking time, the increase of sample permeability increases first and then decreases.

Observability of satellite launcher navigation with INS, GPS, attitude sensors and reference trajectory

NASA Astrophysics Data System (ADS)

Beaudoin, Yanick; Desbiens, André; Gagnon, Eric; Landry, René

2018-01-01

The navigation system of a satellite launcher is of paramount importance. In order to correct the trajectory of the launcher, the position, velocity and attitude must be known with the best possible precision. In this paper, the observability of four navigation solutions is investigated. The first one is the INS/GPS couple. Then, attitude reference sensors, such as magnetometers, are added to the INS/GPS solution. The authors have already demonstrated that the reference trajectory could be used to improve the navigation performance. This approach is added to the two previously mentioned navigation systems. For each navigation solution, the observability is analyzed with different sensor error models. First, sensor biases are neglected. Then, sensor biases are modelled as random walks and as first order Markov processes. The observability is tested with the rank and condition number of the observability matrix, the time evolution of the covariance matrix and sensitivity to measurement outlier tests. The covariance matrix is exploited to evaluate the correlation between states in order to detect structural unobservability problems. Finally, when an unobservable subspace is detected, the result is verified with theoretical analysis of the navigation equations. The results show that evaluating only the observability of a model does not guarantee the ability of the aiding sensors to correct the INS estimates within the mission time. The analysis of the covariance matrix time evolution could be a powerful tool to detect this situation, however in some cases, the problem is only revealed with a sensitivity to measurement outlier test. None of the tested solutions provide GPS position bias observability. For the considered mission, the modelling of the sensor biases as random walks or Markov processes gives equivalent results. Relying on the reference trajectory can improve the precision of the roll estimates. But, in the context of a satellite launcher, the roll estimation error and gyroscope bias are only observable if attitude reference sensors are present.

Inverse solutions for electrical impedance tomography based on conjugate gradients methods

NASA Astrophysics Data System (ADS)

Wang, M.

2002-01-01

A multistep inverse solution for two-dimensional electric field distribution is developed to deal with the nonlinear inverse problem of electric field distribution in relation to its boundary condition and the problem of divergence due to errors introduced by the ill-conditioned sensitivity matrix and the noise produced by electrode modelling and instruments. This solution is based on a normalized linear approximation method where the change in mutual impedance is derived from the sensitivity theorem and a method of error vector decomposition. This paper presents an algebraic solution of the linear equations at each inverse step, using a generalized conjugate gradients method. Limiting the number of iterations in the generalized conjugate gradients method controls the artificial errors introduced by the assumption of linearity and the ill-conditioned sensitivity matrix. The solution of the nonlinear problem is approached using a multistep inversion. This paper also reviews the mathematical and physical definitions of the sensitivity back-projection algorithm based on the sensitivity theorem. Simulations and discussion based on the multistep algorithm, the sensitivity coefficient back-projection method and the Newton-Raphson method are given. Examples of imaging gas-liquid mixing and a human hand in brine are presented.

Social Context as an Indirect Trigger in EFL Contexts: Issues and Solutions

ERIC Educational Resources Information Center

Gholami, Reza; Rahman, Sharifah Zainab Abd; Mustapha, Ghazali

2012-01-01

This paper investigates the value of the social context and its role in learning a second language in different contexts. Social context is believed to be able to influence attitude and motivation. It also provides learning opportunities which give rise to learner's outcomes. In fact, students acquire a language by using it in social interaction…

IoT-Forensics Meets Privacy: Towards Cooperative Digital Investigations

PubMed Central

Lopez, Javier

2018-01-01

IoT-Forensics is a novel paradigm for the acquisition of electronic evidence whose operation is conditioned by the peculiarities of the Internet of Things (IoT) context. As a branch of computer forensics, this discipline respects the most basic forensic principles of preservation, traceability, documentation, and authorization. The digital witness approach also promotes such principles in the context of the IoT while allowing personal devices to cooperate in digital investigations by voluntarily providing electronic evidence to the authorities. However, this solution is highly dependent on the willingness of citizens to collaborate and they may be reluctant to do so if the sensitive information within their personal devices is not sufficiently protected when shared with the investigators. In this paper, we provide the digital witness approach with a methodology that enables citizens to share their data with some privacy guarantees. We apply the PRoFIT methodology, originally defined for IoT-Forensics environments, to the digital witness approach in order to unleash its full potential. Finally, we show the feasibility of a PRoFIT-compliant digital witness with two use cases. PMID:29414864

IoT-Forensics Meets Privacy: Towards Cooperative Digital Investigations.

PubMed

Nieto, Ana; Rios, Ruben; Lopez, Javier

2018-02-07

IoT-Forensics is a novel paradigm for the acquisition of electronic evidence whose operation is conditioned by the peculiarities of the Internet of Things (IoT) context. As a branch of computer forensics, this discipline respects the most basic forensic principles of preservation, traceability, documentation, and authorization. The digital witness approach also promotes such principles in the context of the IoT while allowing personal devices to cooperate in digital investigations by voluntarily providing electronic evidence to the authorities. However, this solution is highly dependent on the willingness of citizens to collaborate and they may be reluctant to do so if the sensitive information within their personal devices is not sufficiently protected when shared with the investigators. In this paper, we provide the digital witness approach with a methodology that enables citizens to share their data with some privacy guarantees. We apply the PRoFIT methodology, originally defined for IoT-Forensics environments, to the digital witness approach in order to unleash its full potential. Finally, we show the feasibility of a PRoFIT-compliant digital witness with two use cases.

Sensitivities of Soap Solutions in Leak Detection

NASA Technical Reports Server (NTRS)

Stuck, D.; Lam, D. Q.; Daniels, C.

1985-01-01

Document describes method for determining minimum leak rate to which soap-solution leak detectors sensitive. Bubbles formed at smaller leak rates than previously assumed. In addition to presenting test results, document discusses effects of joint-flange configurations, properties of soap solutions, and correlation of test results with earlier data.

Children's Sensitivity to the Knowledge Expressed in Pedagogical and Nonpedagogical Contexts

ERIC Educational Resources Information Center

Gelman, Susan A.; Ware, Elizabeth A.; Manczak, Erika M.; Graham, Susan A.

2013-01-01

The present studies test 2 hypotheses: (1) that pedagogical contexts especially convey generic information (Csibra & Gergely, 2009) and (2) that young children are sensitive to this aspect of pedagogy. We examined generic language (e.g., "'Elephants' live in Africa") in 3 studies, focusing on informational versus narrative children's…

The Need for Context-Sensitive Measures of Educational Quality in Transnational Higher Education

ERIC Educational Resources Information Center

Pyvis, David

2011-01-01

This paper argues that the current approach to educational quality formation in transnational higher education promotes educational imperialism, and that guidelines and practices should be altered to embrace context-sensitive measures of quality. The claims are sustained by findings from a study that investigated how academics understood and…

Co-evolution of cooperation and cognition: the impact of imperfect deliberation and context-sensitive intuition

PubMed Central

Kagan, Ari; Rand, David G.

2017-01-01

How does cognitive sophistication impact cooperation? We explore this question using a model of the co-evolution of cooperation and cognition. In our model, agents confront social dilemmas and coordination games, and make decisions using intuition or deliberation. Intuition is automatic and effortless, but relatively (although not necessarily completely) insensitive to context. Deliberation, conversely, is costly but relatively (although not necessarily perfectly) sensitive to context. We find that regardless of the sensitivity of intuition and imperfection of deliberation, deliberating undermines cooperation in social dilemmas, whereas deliberating can increase cooperation in coordination games if intuition is sufficiently sensitive. Furthermore, when coordination games are sufficiently likely, selection favours a strategy whose intuitive response ignores the contextual cues available and cooperates across contexts. Thus, we see how simple cognition can arise from active selection for simplicity, rather than just be forced to be simple due to cognitive constraints. Finally, we find that when deliberation is imperfect, the favoured strategy increases cooperation in social dilemmas (as a result of reducing deliberation) as the benefit of cooperation to the recipient increases. PMID:28330915

Cross reactive arrays of three-way junction sensors for steroid determination

NASA Technical Reports Server (NTRS)

Stojanovic, Milan N. (Inventor); Nikic, Dragan B. (Inventor); Landry, Donald (Inventor)

2008-01-01

This invention provides analyte sensitive oligonucleotide compositions for detecting and analyzing analytes in solution, including complex solutions using cross reactive arrays of analyte sensitive oligonucleotide compositions.

Contextual modulation of pain sensitivity utilising virtual environments

PubMed Central

Smith, Ashley; Carlow, Klancy; Biddulph, Tara; Murray, Brooke; Paton, Melissa; Harvie, Daniel S

2017-01-01

Background: Investigating psychological mechanisms that modulate pain, such as those that might be accessed by manipulation of context, is of great interest to researchers seeking to better understand and treat pain. The aim of this study was to better understand the interaction between pain sensitivity, and contexts with inherent emotional and social salience – by exploiting modern immersive virtual reality (VR) technology. Methods: A within-subjects, randomised, double-blinded, repeated measures (RM) design was used. In total, 25 healthy participants were exposed to neutral, pleasant, threatening, socially positive and socially negative contexts, using an Oculus Rift DK2. Pressure pain thresholds (PPTs) were recorded in each context, as well as prior to and following the procedure. We also investigated whether trait anxiety and pain catastrophisation interacted with the relationship between the different contexts and pain. Results: Pressure pain sensitivity was not modulated by context (p = 0.48). Anxiety and pain catastrophisation were not significantly associated with PPTs, nor did they interact with the relationship between context and PPTs. Conclusion: Contrary to our hypothesis, socially and emotionally salient contexts did not influence pain thresholds. In light of other research, we suggest that pain outcomes might only be tenable to manipulation by contextual cues if they specifically manipulate the meaning of the pain-eliciting stimulus, rather than manipulate psychological state generally – as per the current study. Future research might exploit immersive VR technology to better explore the link between noxious stimuli and contexts that directly alter its threat value. PMID:28491299

Overshadowing and Potentiation of Illness-Based Context Conditioning

ERIC Educational Resources Information Center

Sansa, Joan; Artigas, Antonio A.; Prados, Jose

2007-01-01

In five experiments using rats, we investigated compound context-flavor conditioning. The subjects were allowed to spend time in the target context, where they had access to a flavored solution (either citric acid or saccharine) before receiving an injection of LiCl. Context aversion was then assessed by using a blocking procedure. When the flavor…

Security and Dependability Solutions for Networks and Devices

NASA Astrophysics Data System (ADS)

Gücrgens, Sigrid; Fuchs, Andreas

In this chapter we give an overview over the denotation of the SERENITY artefacts S&D Classes, Patterns and Implementations in the context of networks and devices. In order to demonstrate their necessity we sketch an example for confidential and authentic communication and storage that utilizes a trusted platform module, and model the relevant pattern. We then dissociate solutions for network and device related S&D requirements from those targeting the context of organizational or workflow and web services based solutions. Then we give a summary of the broad field of application for network and device solutions. Finally we clarify the meaning and interaction between classes, patterns and implementations by giving some concrete examples.

Effects of short-term inpatient treatment on sensitivity to a size contrast illusion in first-episode psychosis and multiple-episode schizophrenia.

PubMed

Silverstein, Steven M; Keane, Brian P; Wang, Yushi; Mikkilineni, Deepthi; Paterno, Danielle; Papathomas, Thomas V; Feigenson, Keith

2013-01-01

In the Ebbinghaus illusion, a shape appears larger than its actual size when surrounded by small shapes and smaller than its actual size when surrounded by large shapes. Resistance to this visual illusion has been previously reported in schizophrenia, and linked to disorganized symptoms and poorer prognosis in cross-sectional studies. It is unclear, however, when in the course of illness this resistance first emerges or how it varies longitudinally with illness phase. We addressed these issues by having first-episode psychosis patients, multiple-episode schizophrenia patients and healthy controls complete a psychophysical task at two different time points, corresponding to hospital admission and discharge for patients. The task required judging the relative size of two circular targets centered on either side of the screen. Targets were presented without context (baseline), or were surrounded by shapes that made the size judgment harder or easier (misleading and helpful contexts, respectively). Context sensitivity was operationalized as the amount of improvement relative to baseline in the helpful condition minus the amount of decrement relative to baseline in the misleading condition. At hospital admission, context sensitivity was lower in the multiple-episode group than in the other groups, and was marginally less in the first episode than in the control group. In addition, schizophrenia patients were significantly more and less accurate than the other groups in the misleading and helpful conditions, respectively. At discharge, all groups exhibited similar context sensitivity. In general, poorer context sensitivity was related to higher levels of disorganized symptoms, and lower level of depression, excitement, and positive symptoms. Resistance to the Ebbinghaus illusion, as a characteristic of the acute phase of illness in schizophrenia, increases in magnitude after the first episode of psychosis. This suggests that visual context processing is a state-marker in schizophrenia and a biomarker of relapse and recovery.

Adolescent Neurological Development and Implications for Health and Well-Being

PubMed Central

Griffin, Angela

2017-01-01

Adolescence is evolution’s solution to bringing the capacity of our large, complex brains to fruition. It is a critical period for brain development and the experiences of each adolescent during this time helps to shape their adult brain. Brain developments lead to both the hormonal changes and the emotional, cognitive, and behavioral characteristics of the teenage years. They drive a growth towards independence via more complex reasoning skills, increased importance of social affiliations outside the family, and an urge to experiment and explore boundaries. In the context of still incomplete inhibitory systems, a heightened sensitivity to rewards, including the need for social acceptance, can mean risk-taking or impulsive behaviour in some. The continued plasticity of the brain can also mean a creativity and openness to novel solutions. These normative steps of adolescence are especially relevant to young people with chronic health conditions. An understanding of brain development at this time can help us appreciate the perspective and priorities of adolescents with health conditions. It can also guide us towards better ways of collaborating with them. PMID:28961184

Context Blindness in Autism Spectrum Disorder: Not Using the Forest to See the Trees as Trees

ERIC Educational Resources Information Center

Vermeulen, Peter

2015-01-01

Because of the importance of contextual sensitivity in several cognitive processes that are affected in autism spectrum disorder (ASD), such as social cognition, understanding of language, or cognitive shifting, we argue that a lack of contextual sensitivity or "context blindness" should be given more attention in a neurocognitive…

Maternal Sensitivity and Child Secure Base Use in Early Childhood: Studies in Different Cultural Contexts

ERIC Educational Resources Information Center

Posada, German; Trumbell, Jill; Noblega, Magaly; Plata, Sandra; Peña, Paola; Carbonell, Olga A.; Lu, Ting

2016-01-01

This study tested whether maternal sensitivity and child security are related during early childhood and whether such an association is found in different cultural and social contexts. Mother-child dyads (N = 237) from four different countries (Colombia, Mexico, Peru, and the United States) were observed in naturalistic settings when children were…

Polarization-sensitive nanowire photodetectors based on solution-synthesized CdSe quantum-wire solids.

PubMed

Singh, Amol; Li, Xiangyang; Protasenko, Vladimir; Galantai, Gabor; Kuno, Masaru; Xing, Huili Grace; Jena, Debdeep

2007-10-01

Polarization-sensitive photodetectors are demonstrated using solution-synthesized CdSe nanowire (NW) solids. Photocurrent action spectra taken with a tunable white light source match the solution linear absorption spectra of the NWs, showing that the NW network is responsible for the device photoconductivity. Temperature-dependent transport measurements reveal that carriers responsible for the dark current through the nanowire solids are thermally excited across CdSe band gap. The NWs are aligned using dielectrophoresis between prepatterned electrodes using conventional optical photolithography. The photocurrent through the NW solid is found to be polarization-sensitive, consistent with complementary absorption (emission) measurements of both single wires and their ensembles. The range of solution-processed semiconducting NW materials, their facile synthesis, ease of device fabrication, and compatibility with a variety of substrates make them attractive for potential nanoscale polarization-sensitive photodetectors.

Cardioprotective effect of diadenosine tetraphosphate (AP4A) preservation in hypothermic storage and its relation with mitochondrial ATP-sensitive potassium channels.

PubMed

Ahmet, I; Sawa, Y; Nishimura, M; Kitakaze, M; Matsuda, H

2000-01-15

The preconditioning effect of diadenosine tetraphosphate (AP4A) was reported in ischemia/reperfused hearts, but its effect in heart preservation was unknown. According to the possible role of mitochondrial ATP-sensitive potassium channel (mK(ATP) channel) in the effect of ischemic preconditioning, the contribution of mK(ATP) channel to the effect of AP4A was tested. Isolated rat hearts were arrested and preserved by Eurocollin's (EC) solution at 4 degrees C for 8 hr. AP4A (80 microM) or AP4A with the 5-hydroxydecanoic acid (100 microM), a selective inhibitor of the mK(ATP) channel, was added into the EC solution. The preischemic and postischemic cardiac functions were evaluated on a buffer-perfused Langendorff apparatus before storage and after 20 min of reperfusion. AP4A administration improved the recovery of poststorage cardiac functions (the rate-pressure production, left ventricular systolic pressure, heart rate, coronary flow rate, and derivative of left ventricular systolic pressure; P<0.05) and reduced the leakage of lactate dehydrate and creatine kinase during reperfusion, compared with EC alone. Those effects of AP4A were completely reversed by 5-hydroxydecanoic acid administration in combination subjects. AP4A administration protects the heart through opening of the mK(ATP) channel during hypothermic preservation. Thus, addition of AP4A into cardioplegia may be a novel method of ischemic preconditioning in the transplantation context.

Continuum topology optimization considering uncertainties in load locations based on the cloud model

NASA Astrophysics Data System (ADS)

Liu, Jie; Wen, Guilin

2018-06-01

Few researchers have paid attention to designing structures in consideration of uncertainties in the loading locations, which may significantly influence the structural performance. In this work, cloud models are employed to depict the uncertainties in the loading locations. A robust algorithm is developed in the context of minimizing the expectation of the structural compliance, while conforming to a material volume constraint. To guarantee optimal solutions, sufficient cloud drops are used, which in turn leads to low efficiency. An innovative strategy is then implemented to enormously improve the computational efficiency. A modified soft-kill bi-directional evolutionary structural optimization method using derived sensitivity numbers is used to output the robust novel configurations. Several numerical examples are presented to demonstrate the effectiveness and efficiency of the proposed algorithm.

The Rayleigh-Taylor instability in a self-gravitating two-layer viscous sphere

NASA Astrophysics Data System (ADS)

Mondal, Puskar; Korenaga, Jun

2018-03-01

The dispersion relation of the Rayleigh-Taylor instability in the spherical geometry is of profound importance in the context of the Earth's core formation. Here we present a complete derivation of this dispersion relation for a self-gravitating two-layer viscous sphere. Such relation is, however, obtained through the solution of a complex transcendental equation, and it is difficult to gain physical insights directly from the transcendental equation itself. We thus also derive an empirical formula to compute the growth rate, by combining the Monte Carlo sampling of the relevant model parameter space with linear regression. Our analysis indicates that the growth rate of Rayleigh-Taylor instability is most sensitive to the viscosity of inner layer in a physical setting that is most relevant to the core formation.

Geyser periodicity and the response of geysers to deformation

USGS Publications Warehouse

Ingebritsen, S.E.; Rojstaczer, S.A.

1996-01-01

Numerical simulations of multiphase fluid and heat transport through a porous medium define combinations of rock properties and boundary conditions which lead to geyser-like periodic discharge. Within the rather narrow range of conditions that allow geyser-like behavior, eruption frequency and discharge are highly sensitive to the intrinsic permeabilities of the geyser conduit and the surrounding rock matrix, to the relative permeability functions assumed, and to pressure gradients in the matrix. In theory, heats pipes (concomitant upward flow of steam and downward flow of liquid) can exist under similar conditions, but our simulations suggest that the periodic solution is more stable. Simulated time series of geyser discharge are chaotic, but integrated quantities such as eruption frequency and mass discharge per eruption are free of chaos. These results may explain the observed sensitivity of natural geysers to small strains such as those caused by remote earthquakes, if ground motion is sufficient to induce permeability changes. Changes in geyser behavior caused by minor preseismic deformation, periodic surface loading, and Earth tides are more difficult to explain in the context of our current model. Copyright 1996 by the American Geophysical Union.

Effects of the Multiple Solutions and Question Prompts on Generalization and Justification for Non-Routine Mathematical Problem Solving in a Computer Game Context

ERIC Educational Resources Information Center

Lee, Chun-Yi; Chen, Ming-Jang; Chang, Wen-Long

2014-01-01

The aim of this study is to investigate the effects of solution methods and question prompts on generalization and justification of non-routine problem solving for Grade 9 students. The learning activities are based on the context of the frog jumping game. In addition, related computer tools were used to support generalization and justification of…

The Power of Numbers. A Teacher's Guide to Mathematics in a Social Studies Context. An Interdisciplinary Curriculum.

ERIC Educational Resources Information Center

Gross, Fred E.; And Others

This document is the teacher's guide for a curriculum designed to teach mathematics in a social studies context. It provides mathematical experiences in real world contexts that help students interpret, experiment, communicate, and look for multiple solutions to complex problems. The curriculum uses mathematics in context to help students develop…

Variational Methods in Sensitivity Analysis and Optimization for Aerodynamic Applications

NASA Technical Reports Server (NTRS)

Ibrahim, A. H.; Hou, G. J.-W.; Tiwari, S. N. (Principal Investigator)

1996-01-01

Variational methods (VM) sensitivity analysis, which is the continuous alternative to the discrete sensitivity analysis, is employed to derive the costate (adjoint) equations, the transversality conditions, and the functional sensitivity derivatives. In the derivation of the sensitivity equations, the variational methods use the generalized calculus of variations, in which the variable boundary is considered as the design function. The converged solution of the state equations together with the converged solution of the costate equations are integrated along the domain boundary to uniquely determine the functional sensitivity derivatives with respect to the design function. The determination of the sensitivity derivatives of the performance index or functional entails the coupled solutions of the state and costate equations. As the stable and converged numerical solution of the costate equations with their boundary conditions are a priori unknown, numerical stability analysis is performed on both the state and costate equations. Thereafter, based on the amplification factors obtained by solving the generalized eigenvalue equations, the stability behavior of the costate equations is discussed and compared with the state (Euler) equations. The stability analysis of the costate equations suggests that the converged and stable solution of the costate equation is possible only if the computational domain of the costate equations is transformed to take into account the reverse flow nature of the costate equations. The application of the variational methods to aerodynamic shape optimization problems is demonstrated for internal flow problems at supersonic Mach number range. The study shows, that while maintaining the accuracy of the functional sensitivity derivatives within the reasonable range for engineering prediction purposes, the variational methods show a substantial gain in computational efficiency, i.e., computer time and memory, when compared with the finite difference sensitivity analysis.

Stability of the Kasner universe in f (T ) gravity

NASA Astrophysics Data System (ADS)

Paliathanasis, Andronikos; Said, Jackson Levi; Barrow, John D.

2018-02-01

f (T ) gravity theory offers an alternative context in which to consider gravitational interactions where torsion, rather than curvature, is the mechanism by which gravitation is communicated. We investigate the stability of the Kasner solution with several forms of the arbitrary Lagrangian function examined within the f (T ) context. This is a Bianchi type-I vacuum solution with anisotropic expansion factors. In the f (T ) gravity setting, the solution must conform to a set of conditions in order to continue to be a vacuum solution of the generalized field equations. With this solution in hand, the perturbed field equations are determined for power-law and exponential forms of the f (T ) function. We find that the point which describes the Kasner solution is a saddle point which means that the singular solution is unstable. However, we find the de Sitter universe is a late-time attractor. In general relativity, the cosmological constant drives the isotropization of the spacetime while in this setting the extra f (T ) contributions now provide this impetus.

Behavioral mechanisms of context fear generalization in mice

PubMed Central

Huckleberry, Kylie A.; Ferguson, Laura B.

2016-01-01

There is growing interest in generalization of learned contextual fear, driven in part by the hypothesis that mood and anxiety disorders stem from impaired hippocampal mechanisms of fear generalization and discrimination. However, there has been relatively little investigation of the behavioral and procedural mechanisms that might control generalization of contextual fear. We assessed the relative contribution of different contextual features to context fear generalization and characterized how two common conditioning protocols—foreground (uncued) and background (cued) contextual fear conditioning—affected context fear generalization. In one experiment, mice were fear conditioned in context A, and then tested for contextual fear both in A and in an alternate context created by changing a subset of A's elements. The results suggest that floor configuration and odor are more salient features than chamber shape. A second experiment compared context fear generalization in background and foreground context conditioning. Although foreground conditioning produced more context fear than background conditioning, the two procedures produced equal amounts of generalized fear. Finally, results indicated that the order of context tests (original first versus alternate first) significantly modulates context fear generalization, perhaps because the original and alternate contexts are differentially sensitive to extinction. Overall, results demonstrate that context fear generalization is sensitive to procedural variations and likely reflects the operation of multiple interacting psychological and neural mechanisms. PMID:27918275

Immediate impact on the rim zone of cement based materials due to chemical attack

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

Schwotzer, M., E-mail: matthias.schwotzer@kit.edu; Scherer, T.; Gerdes, A.

2015-01-15

Cement based materials are in their widespread application fields exposed to various aqueous environments. This can lead to serious chemical changes affecting the durability of the materials. In particular in the context of service life prediction a detailed knowledge of the reaction mechanisms is a necessary base for the evaluation of the aggressivity of an aqueous medium and this is deduced commonly from long term investigations. However, these processes start immediately at the material/water-interface, when a cementitious system comes into contact with an aqueous solution, altering here the chemical composition and microstructure. This rim zone represents the first hurdle thatmore » has to be overcome by an attacking aqueous solution. Therefore, the properties of the surface near area should be closely associated with the further course of deterioration processes by reactive transport. In this context short term exposure experiments with hardened cement paste over 4 and 48 h have been carried out with demineralized water, hard tap water and different sulfate solutions. In order to investigate immediate changes in the near-surface region, depth profile cuts have been performed on the cement paste samples by means of focused ion beam preparation techniques. A scanning beam of Gallium ions is applied to cut a sharp edge in the cement paste surface, providing insights into the composition and microstructure of the upper ten to hundred microns. Electron microscopic investigations on such a section of the rim zone, together with surface sensitive X-ray diffraction accompanied by a detailed characterization of the bulk composition confirm that the properties of the material/water interface are of relevance for the durability of cement based systems in contact with aqueous solutions. In this manner, focused ion beam investigations constitute auspicious tools to contribute to a more sophisticated understanding of the reaction mechanisms. - Highlights: • The chemical stability is related to the properties of material/water interface. • Properties of the rim zone readjust quickly, triggered by hydrochemical conditions. • Durability research can be improved by combining FIB techniques and common analytics.« less

Healthcare workers' perceptions of lean: a context-sensitive, mixed methods study in three Swedish hospitals.

PubMed

Holden, Richard J; Eriksson, Andrea; Andreasson, Jörgen; Williamsson, Anna; Dellve, Lotta

2015-03-01

As the application of lean in healthcare expands, further research is needed in at least two areas: first, on the role of context in shaping lean and its consequences and second, on how healthcare workers perceive lean. Accordingly, this context-sensitive, mixed methods study addressed how hospital workers' perceptions of lean varied across contexts in three Swedish hospitals. Registered nurses and physicians at the hospitals and across units differing in acuity completed standardized surveys (N = 236, 57% response rate) about their perceptions of hospital-wide lean implementation. Perceptions varied by: hospital context, with one hospital's employees reporting the least favorable perceptions; unit acuity, with higher-acuity units reporting more favorable perceptions; and professional role, with nurses reporting more favorable perceptions than physicians. Individual interviews, group interviews, and observations provided insight about these dissimilar contexts and possible explanations for context-specific variability. Findings are discussed with respect to strategies for implementing lean in healthcare; the importance of attending to levels, context, and worker consequences of lean; and directions for future research. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Healthcare workers' perceptions of lean: A context-sensitive, mixed methods study in three Swedish hospitals

PubMed Central

Holden, Richard J.; Eriksson, Andrea; Andreasson, Jörgen; Williamsson, Anna; Dellve, Lotta

2014-01-01

As the application of lean in healthcare expands, further research is needed in at least two areas: first, on the role of context in shaping lean and its consequences and second, on how healthcare workers perceive lean. Accordingly, this context-sensitive, mixed methods study addressed how hospital workers' perceptions of lean varied across contexts in three Swedish hospitals. Registered nurses and physicians at the hospitals and across units differing in acuity completed standardized surveys (N=236, 57% response rate) about their perceptions of hospital-wide lean implementation. Perceptions varied by: hospital context, with one hospital's employees reporting the least favorable perceptions; unit acuity, with higher-acuity units reporting more favorable perceptions; and professional role, with nurses reporting more favorable perceptions than physicians. Individual interviews, group interviews, and observations provided insight about these dissimilar contexts and possible explanations for context-specific variability. Findings are discussed with respect to strategies for implementing lean in healthcare; the importance of attending to levels, context, and worker consequences of lean; and directions for future research. PMID:25479987

The design, fabrication, and photocatalytic utility of nanostructured semiconductors: focus on TiO2-based nanostructures

PubMed Central

Banerjee, Arghya Narayan

2011-01-01

Recent advances in basic fabrication techniques of TiO2-based nanomaterials such as nanoparticles, nanowires, nanoplatelets, and both physical- and solution-based techniques have been adopted by various research groups around the world. Our research focus has been mainly on various deposition parameters used for fabricating nanostructured materials, including TiO2-organic/inorganic nanocomposite materials. Technically, TiO2 shows relatively high reactivity under ultraviolet light, the energy of which exceeds the band gap of TiO2. The development of photocatalysts exhibiting high reactivity under visible light allows the main part of the solar spectrum to be used. Visible light-activated TiO2 could be prepared by doping or sensitizing. As far as doping of TiO2 is concerned, in obtaining tailored material with improved properties, metal and nonmetal doping has been performed in the context of improved photoactivity. Nonmetal doping seems to be more promising than metal doping. TiO2 represents an effective photocatalyst for water and air purification and for self-cleaning surfaces. Additionally, it can be used as an antibacterial agent because of its strong oxidation activity and superhydrophilicity. Therefore, applications of TiO2 in terms of photocatalytic activities are discussed here. The basic mechanisms of the photoactivities of TiO2 and nanostructures are considered alongside band structure engineering and surface modification in nanostructured TiO2 in the context of doping. The article reviews the basic structural, optical, and electrical properties of TiO2, followed by detailed fabrication techniques of 0-, 1-, and quasi-2-dimensional TiO2 nanomaterials. Applications and future directions of nanostructured TiO2 are considered in the context of various photoinduced phenomena such as hydrogen production, electricity generation via dye-sensitized solar cells, photokilling and self-cleaning effect, photo-oxidation of organic pollutant, wastewater management, and organic synthesis. PMID:24198485

A Knowledge-Based Approach to Retrieving Teaching Materials for Context-Aware Learning

ERIC Educational Resources Information Center

Shih, Wen-Chung; Tseng, Shian-Shyong

2009-01-01

With the rapid development of wireless communication and sensor technologies, ubiquitous learning has become a promising solution to educational problems. In context-aware ubiquitous learning environments, it is required that learning content is retrieved according to environmental contexts, such as learners' location. Also, a learning content…

Promoting Conceptual Coherence within Context-Based Biology Education

ERIC Educational Resources Information Center

Ummels, Micha H. J.; Kamp, Marcel J. A.; De Kroon, Hans; Boersma, Kerst Th.

2015-01-01

In secondary science education, the learning and teaching of coherent conceptual understanding are often problematic. Context-based education has been proposed as a partial solution to this problem. This study aims to gain insight into the development of conceptual coherence and how context-embedded learning-teaching activities (LT) can promote…

Females are sensitive to unpleasant human emotions regardless of the emotional context of photographs.

PubMed

Kato, Ryousuke; Takeda, Yuji

2017-06-09

Previous studies have demonstrated that females exhibit higher sensitivity than males to the emotional state of a person in a photograph. The present study examined whether such females' sensitivity to human emotions could be observed even when the background emotional contexts were incongruent with facial expressions. The late positive potential (LPP) was measured while 19-female and 15-male participants viewed a photograph of a face with varied emotional expressions (pleasant, neutral, or unpleasant) superimposed on a background photograph with varied valences (pleasant, neutral, or unpleasant). The results showed that unpleasant background photographs elicited a larger LPP compared to pleasant and neutral background photographs in both female and male participants. In contrast, a larger LPP for the unpleasant face photographs was observed only in female participants. Furthermore, the effect of face photographs did not interact with the effect of background photographs. These results suggest that females are sensitive to human emotions regardless of the emotional context. Copyright © 2017 Elsevier B.V. All rights reserved.

A before-and-after study of traffic conflicts at the U.S. Route One entrance to Camden Hills State Park : an evaluation of a portion of a context sensitive design project.

DOT National Transportation Integrated Search

2007-09-01

Route 1 has been reconstructed as a Context Sensitive Design Project in the Camden, : Maine area. The purpose of this study is to evaluate the safety effect of the reconstruction of the highway at the entrances to the Camden Hills State Park. The two...

Record completeness and data concordance in an anesthesia information management system using context-sensitive mandatory data-entry fields.

PubMed

Avidan, Alexander; Weissman, Charles

2012-03-01

Use of an anesthesia information management system (AIMS) does not insure record completeness and data accuracy. Mandatory data-entry fields can be used to assure data completeness. However, they are not suited for data that is mandatory depending on the clinical situation (context sensitive). For example, information on equal breath sounds should be mandatory with tracheal intubation, but not with mask ventilation. It was hypothesized that employing context-sensitive mandatory data-entry fields can insure high data-completeness and accuracy while maintaining usability. A commercial off-the-shelf AIMS was enhanced using its built-in VBScript programming tool to build event-driven forms with context-sensitive mandatory data-entry fields. One year after introduction of the system, all anesthesia records were reviewed for data completeness. Data concordance, used as a proxy for accuracy, was evaluated using verifiable age-related data. Additionally, an anonymous satisfaction survey on general acceptance and usability of the AIMS was performed. During the initial 12 months of AIMS use, 12,241 (99.6%) of 12,290 anesthesia records had complete data. Concordances of entered data (weight, size of tracheal tubes, laryngoscopy blades and intravenous catheters) with patients' ages were 98.7-99.9%. The AIMS implementation was deemed successful by 98% of the anesthesiologists. Users rated the AIMS usability in general as very good and the data-entry forms in particular as comfortable. Due to the complexity and the high costs of implementation of an anesthesia information management system it was not possible to compare various system designs (for example with or without context-sensitive mandatory data entry-fields). Therefore, it is possible that a different or simpler design would have yielded the same or even better results. This refers also to the evaluation of usability, since users did not have the opportunity to work with different design approaches or even different computer programs. Using context-sensitive mandatory fields in an anesthesia information management system was associated with high record completeness rate and data concordance. In addition, the system's usability was rated as very good by its users. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Octanol reduces end-plate channel lifetime

PubMed Central

Gage, Peter W.; McBurney, Robert N.; Van Helden, Dirk

1978-01-01

1. Post-synaptic effects of n-octanol at concentrations of 0·1-1 mM were examined in toad sartorius muscles by use of extracellular and voltage-clamp techniques. 2. Octanol depressed the amplitude and duration of miniature end-plate currents and hence depressed neuromuscular transmission. 3. The decay of miniature end-plate currents remained exponential in octanol solutions even when the time constant of decay (τD) was decreased by 80-90%. 4. The lifetime of end-plate channels, obtained by analysis of acetylcholine noise, was also decreased by octanol. The average lifetime measured from noise spectra agreed reasonably well with the time constant of decay of miniature end-plate currents, both in control solution and in octanol solutions. 5. Octanol caused a reduction in the conductance of end-plate channels. Single channel conductance was on average about 25 pS in control solution and 20 pS in octanol. 6. In most cells the normal voltage sensitivity of the decay of miniature end-plate currents was retained in octanol solutions. The lifetime of end-plate channels measured from acetylcholine noise also remained voltage-sensitive in octanol solutions. In some experiments in which channel lifetime was exceptionally reduced the voltage sensitivity was less than normal. 7. In octanol solutions, τD was still very sensitive to temperature changes in most cells although in some the temperature sensitivity of τD was clearly reduced. Changes in τD with temperature could generally be fitted by the Arrhenius equation suggesting that a single step reaction controlled the decay of currents both in control and in octanol solutions. In some cells in which τD became less than 0·3 ms, the relationship between τD and temperature became inconsistent with the Arrhenius equation. 8. As the decay of end-plate currents in octanol solutions remains exponential, and the voltage and temperature sensitivity can be unchanged even when τD is significantly reduced, it seems likely that octanol decreases τD by increasing the rate of the reaction which normally controls the lifetime of end-plate channels. PMID:203674

Conditional Solvation Thermodynamics of Isoleucine in Model Peptides and the Limitations of the Group-Transfer Model

PubMed Central

2015-01-01

The hydration thermodynamics of the amino acid X relative to the reference G (glycine) or the hydration thermodynamics of a small-molecule analog of the side chain of X is often used to model the contribution of X to protein stability and solution thermodynamics. We consider the reasons for successes and limitations of this approach by calculating and comparing the conditional excess free energy, enthalpy, and entropy of hydration of the isoleucine side chain in zwitterionic isoleucine, in extended penta-peptides, and in helical deca-peptides. Butane in gauche conformation serves as a small-molecule analog for the isoleucine side chain. Parsing the hydrophobic and hydrophilic contributions to hydration for the side chain shows that both of these aspects of hydration are context-sensitive. Furthermore, analyzing the solute–solvent interaction contribution to the conditional excess enthalpy of the side chain shows that what is nominally considered a property of the side chain includes entirely nonobvious contributions of the background. The context-sensitivity of hydrophobic and hydrophilic hydration and the conflation of background contributions with energetics attributed to the side chain limit the ability of a single scaling factor, such as the fractional solvent exposure of the group in the protein, to map the component energetic contributions of the model-compound data to their value in the protein. But ignoring the origin of cancellations in the underlying components the group-transfer model may appear to provide a reasonable estimate of the free energy for a given error tolerance. PMID:24650057

Engineering polyelectrolyte multilayer structure at the nanometer length scale by tuning polymer solution conformation.

NASA Astrophysics Data System (ADS)

Boddohi, Soheil; Killingsworth, Christopher; Kipper, Matt

2008-03-01

Chitosan (a weak polycation) and heparin (a strong polyanion) are used to make polyelectrolyte multilayers (PEM). PEM thickness and composition are determined as a function of solution pH (4.6 to 5.8) and ionic strength (0.1 to 0.5 M). Over this range, increasing pH increases the PEM thickness; however, the sensitivity to changes in pH is a strong function of ionic strength. The PEM thickness data are correlated to the polymer conformation in solution. Polyelectrolyte conformation in solution is characterized by gel permeation chromatography (GPC). The highest sensitivity of PEM structure to pH is obtained at intermediate ionic strength. Different interactions govern the conformation and adsorption phenomena at low and high ionic strength, leading to reduced sensitivity to solution pH at extreme ionic strengths. The correspondence between PEM thickness and polymer solution conformation offers opportunities to tune polymer thin film structure at the nanometer length scale by controlling simple, reproducible processing conditions.

Linear landmark extraction in SAR images with application to augmented integrity aero-navigation: an overview to a novel processing chain

NASA Astrophysics Data System (ADS)

Fabbrini, L.; Messina, M.; Greco, M.; Pinelli, G.

2011-10-01

In the context of augmented integrity Inertial Navigation System (INS), recent technological developments have been focusing on landmark extraction from high-resolution synthetic aperture radar (SAR) images in order to retrieve aircraft position and attitude. The article puts forward a processing chain that can automatically detect linear landmarks on highresolution synthetic aperture radar (SAR) images and can be successfully exploited also in the context of augmented integrity INS. The processing chain uses constant false alarm rate (CFAR) edge detectors as the first step of the whole processing procedure. Our studies confirm that the ratio of averages (RoA) edge detector detects object boundaries more effectively than Student T-test and Wilcoxon-Mann-Whitney (WMW) test. Nevertheless, all these statistical edge detectors are sensitive to violation of the assumptions which underlie their theory. In addition to presenting a solution to the previous problem, we put forward a new post-processing algorithm useful to remove the main false alarms, to select the most probable edge position, to reconstruct broken edges and finally to vectorize them. SAR images from the "MSTAR clutter" dataset were used to prove the effectiveness of the proposed algorithms.

Stimulus sensitive gel with radioisotope and methods of making

DOEpatents

Weller, Richard E.; Lind, Michael A.; Fisher, Darrell R.; Gutowska, Anna; Campbell, Allison A.

2005-03-22

The present invention is a thermally reversible stimulus-sensitive gel or gelling copolymer radioisotope carrier that is a linear random copolymer of an [meth-]acrylamide derivative and a hydrophilic comonomer, wherein the linear random copolymer is in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff. Addition of a biodegradable backbone and/or a therapeutic agent imparts further utility. The method of the present invention for making a thermally reversible stimulus-sensitive gelling copolymer radionuclcide carrier has the steps of: (a) mixing a stimulus-sensitive reversible gelling copolymer with an aqueous solvent as a stimulus-sensitive reversible gelling solution; and (b) mixing a radioisotope with said stimulus-sensitive reversible gelling solution as said radioisotope carrier. The gel is enhanced by either combining it with a biodegradable backbone and/or a therapeutic agent in a gelling solution made by mixing the copolymer with an aqueous solvent.

Stimulus sensitive gel with radioisotope and methods of making

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

Weller, Richard E; Lind, Michael A; Fisher, Darrell R

2001-10-02

The present invention is a thermally reversible stimulus-sensitive gel or gelling copolymer radioisotope carrier that is a linear random copolymer of an [meth]acrylamide derivative and a hydrophilic comonomer, wherein the linear random copolymer is in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff. Addition of a biodegradable backbone and/or a therapeutic agent imparts further utility. The method of the present invention for making a thermally reversible stimulus-sensitive gelling copolymer radionuclcide carrier has the steps of: (a) mixing a stimulus-sensitive reversible gelling copolymer withmore » an aqueous solvent as a stimulus-sensitive reversible gelling solution; and (b) mixing a radioisotope with said stimulus-sensitive reversible gelling solution as said radioisotope carrier. The gel is enhanced by either combining it with a biodegradable backbone and/or a therapeutic agent in a gelling solution made by mixing the copolymer with an aqueous solvent.« less

In-situ growth of AuNPs on WS2@U-bent optical fiber for evanescent wave absorption sensor

NASA Astrophysics Data System (ADS)

Zhang, Suzhen; Zhao, Yuefeng; Zhang, Chao; Jiang, Shouzhen; Yang, Cheng; Xiu, Xianwu; Li, Chonghui; Li, Zhen; Zhao, Xiaofei; Man, Baoyuan

2018-05-01

The sensitivity of the evanescent wave absorption sensor is always a hot topic which has been attracted researchers' discussion. It is still a challenge for developing the effective sensor to sensitively detect some biochemical molecules solution in a simple and low-cost way. In this paper, an evanescent wave absorption (EWA) sensor has been presented based on the U-bent multimode fiber coated with tungsten disulfide (WS2) film and in-situ growth of gold nanoparticles (AuNPs) for the detection of ethanol solution and sodium chloride (NaCl) solution. Benefitted from the effective light coupling produced between U-bent probe and AuNPs, we attained the optimal size of the AuNPs by changing the reaction time between WS2 and tetrachloroauric acid (HAuCl4). With the AuNPs/WS2@U-bent optical fiber, we discussed the behaviors of EWA sensor, such as sensitivity, reproducibility, fast response-recovery time and stability. The sensitivity (△A/△C) of the proposed AuNPs/WS2@U-bent optical fiber EWA sensor is 0.65 for the detection of the ethanol solution. Besides, the AuNPs/WS2@U-bent optical fiber EWA sensor exhibits high sensitivity in detection of the sodium chloride (NaCl), which can reach 1.5 when the proposed sensor was immersed into NaCl solution. Our work demonstrates that the U-bent optical fiber EWA sensor may have promising applications in testing the solution of concentration.

Performance enhancement of dye-sensitized solar cells (DSSCs) using a natural sensitizer

NASA Astrophysics Data System (ADS)

Arifin, Zainal; Soeparman, Sudjito; Widhiyanuriyawan, Denny; Sutanto, Bayu; Suyitno

2017-01-01

Dye-sensitized solar cells (DSSCs) based on natural sensitizers have become a topic of significant research because of their urgency and importance in the energy conversion field and the following advantages: ease of fabrication, low-cost solar cell, and usage of nontoxic materials. The natural sensitizer in DSSCs is responsible for the absorption of light as well as the injection of charges to the conduction band of the semiconductor such as TiO2 nanoparticles. In this study, the chlorophyll extracted from papaya leaves was used as a natural sensitizer. Dye molecules were adsorbed by TiO2 nanoparticle surfaces when submerged in the dye solution for 24 h. The concentration of the dye solution influences both the amount of dye loading and the DSSC performance. The amount of adsorbed dye molecules by TiO2 nanoparticle was calculated using a desorption method. As the concentration of dye solution was increased, the dye loading capacity and power conversion efficiency increased. Above 90 mM dye solution concentration, however, the DSSC efficiency decreased because dye precipitated on the TiO2 nanostructure. These characteristics of DSSCs were analyzed under the irradiation of 100 mW/cm2. The best performance of DSSCs was obtained at 90 mM dye solution, with the values of Voc, Jsc, FF, and efficiency of DSSCs being 0.561 V, 0.402 mA/cm2, 41.65%, and 0.094%, respectively.

Activity of water in aqueous systems; a frequently neglected property.

PubMed

Blandamer, Mike J; Engberts, Jan B F N; Gleeson, Peter T; Reis, Joao Carlos R

2005-05-01

In this critical review, the significance of the term 'activity' is examined in the context of the properties of aqueous solutions. The dependence of the activity of water(l) at ambient pressure and 298.15 K on solute molality is examined for aqueous solutions containing neutral solutes, mixtures of neutral solutes and salts. Addition of a solute to water(l) always lowers its thermodynamic activity. For some solutes the stabilisation of water(l) is less than and for others more than in the case where the thermodynamic properties of the aqueous solution are ideal. In one approach this pattern is accounted for in terms of hydrate formation. Alternatively the pattern is analysed in terms of the dependence of practical osmotic coefficients on the composition of the aqueous solution and then in terms of solute-solute interactions. For salt solutions the dependence of the activity of water on salt molalities is compared with that predicted by the Debye-Hückel limiting law. The analysis is extended to consideration of the activities of water in binary aqueous mixtures. The dependence on mole fraction composition of the activity of water in binary aqueous mixtures is examined. Different experimental methods for determining the activity of water in aqueous solutions are critically reviewed. The role of water activity is noted in a biochemical context, with reference to the quality, stability and safety of food and finally with regard to health science.

Early father involvement moderates biobehavioral susceptibility to mental health problems in middle childhood.

PubMed

Boyce, W Thomas; Essex, Marilyn J; Alkon, Abbey; Goldsmith, H Hill; Kraemer, Helena C; Kupfer, David J

2006-12-01

To study how early father involvement and children's biobehavioral sensitivity to social contexts interactively predict mental health symptoms in middle childhood. Fathers' involvement in infant care and maternal symptoms of depression were prospectively ascertained in a community-based study of child health and development in Madison and Milwaukee, WI. In a subsample of 120 children, behavioral, autonomic, and adrenocortical reactivity to standardized challenges were measured as indicators of biobehavioral sensitivity to social context during a 4-hour home assessment in 1998, when the children were 7 years of age. Mental health symptoms were evaluated at age 9 years using parent, child, and teacher reports. Early father involvement and children's biobehavioral sensitivity to context significantly and interactively predicted symptom severity. Among children experiencing low father involvement in infancy, behavioral, autonomic, and adrenocortical reactivity became risk factors for later mental health symptoms. The highest symptom severity scores were found for children with high autonomic reactivity that, as infants, had experienced low father involvement and mothers with symptoms of depression. Among children experiencing minimal paternal caretaking in infancy, heightened biobehavioral sensitivity to social contexts may be an important predisposing factor for the emergence of mental health symptoms in middle childhood. Such predispositions may be exacerbated by the presence of maternal depression.

Pharmacological Targeting of the Host-Pathogen Interaction: Alternatives to Classical Antibiotics to Combat Drug-Resistant Superbugs

PubMed Central

Munguia, Jason; Nizet, Victor

2017-01-01

The rise of multidrug-resistant pathogens and the dearth of new antibiotic development place an existential strain on successful infectious disease therapy. Breakthrough strategies that go beyond classical antibiotic mechanisms are needed to combat this looming public health catastrophe. Reconceptualizing antibiotic therapy in the richer context of the host-pathogen interaction is required for innovative solutions. By defining specific virulence factors, the essence of a pathogen, and pharmacologically neutralizing their activities, one can block disease progression and sensitize microbes to immune clearance. Likewise, host-directed strategies to boost phagocyte bactericidal activity, enhance leukocyte recruitment, or reverse pathogen-induced immunosuppression seek to replicate the success of cancer immunotherapy in the field of infectious diseases. The answer to the threat of multidrug-resistant pathogens lies “outside-the-box” of current antibiotic paradigms. PMID:28283200

Do pain-associated contexts increase pain sensitivity? An investigation using virtual reality.

PubMed

Harvie, Daniel S; Sterling, Michele; Smith, Ashley D

2018-04-30

Pain is not a linear result of nociception, but is dependent on multisensory inputs, psychological factors, and prior experience. Since nociceptive models appear insufficient to explain chronic pain, understanding non-nociceptive contributors is imperative. Several recent models propose that cues associatively linked to painful events might acquire the capacity to augment, or even cause, pain. This experiment aimed to determine whether contexts associated with pain, could modulate mechanical pain thresholds and pain intensity. Forty-eight healthy participants underwent a contextual conditioning procedure, where three neutral virtual reality contexts were paired with either unpredictable noxious stimulation, unpredictable vibrotactile stimulation, or no stimulation. Following the conditioning procedure, mechanical pain thresholds and pain evoked by a test stimulus were examined in each context. In the test phase, the effect of expectancy was equalised across conditions by informing participants when thresholds and painful stimuli would be presented. Contrary to our hypothesis, scenes that were associated with noxious stimulation did not increase mechanical sensitivity (p=0.08), or increase pain intensity (p=0.46). However, an interaction with sex highlighted the possibility that pain-associated contexts may alter pain sensitivity in females but not males (p=0.03). Overall, our data does not support the idea that pain-associated contexts can alter pain sensitivity in healthy asymptomatic individuals. That an effect was shown in females highlights the possibility that some subgroups may be susceptible to such an effect, although the magnitude of the effect may lack real-world significance. If pain-associated cues prove to have a relevant pain augmenting effect, in some subgroups, procedures aimed at extinguishing pain-related associations may have therapeutic potential.

Implicit time accurate simulation of unsteady flow

NASA Astrophysics Data System (ADS)

van Buuren, René; Kuerten, Hans; Geurts, Bernard J.

2001-03-01

Implicit time integration was studied in the context of unsteady shock-boundary layer interaction flow. With an explicit second-order Runge-Kutta scheme, a reference solution to compare with the implicit second-order Crank-Nicolson scheme was determined. The time step in the explicit scheme is restricted by both temporal accuracy as well as stability requirements, whereas in the A-stable implicit scheme, the time step has to obey temporal resolution requirements and numerical convergence conditions. The non-linear discrete equations for each time step are solved iteratively by adding a pseudo-time derivative. The quasi-Newton approach is adopted and the linear systems that arise are approximately solved with a symmetric block Gauss-Seidel solver. As a guiding principle for properly setting numerical time integration parameters that yield an efficient time accurate capturing of the solution, the global error caused by the temporal integration is compared with the error resulting from the spatial discretization. Focus is on the sensitivity of properties of the solution in relation to the time step. Numerical simulations show that the time step needed for acceptable accuracy can be considerably larger than the explicit stability time step; typical ratios range from 20 to 80. At large time steps, convergence problems that are closely related to a highly complex structure of the basins of attraction of the iterative method may occur. Copyright

Environmental Sensitivity in Children: Development of the Highly Sensitive Child Scale and Identification of Sensitivity Groups

ERIC Educational Resources Information Center

Pluess, Michael; Assary, Elham; Lionetti, Francesca; Lester, Kathryn J.; Krapohl, Eva; Aron, Elaine N.; Aron, Arthur

2018-01-01

A large number of studies document that children differ in the degree they are shaped by their developmental context with some being more sensitive to environmental influences than others. Multiple theories suggest that "Environmental Sensitivity" is a common trait predicting the response to negative as well as positive exposures.…

INVENTORY AND ASSESSMENT OF CLIMATE SENSITIVE DECISIONS

EPA Science Inventory

The project will create a pilot inventory of climate-sensitive resource managment decision. The project will develop and demonstrate a new approach to collecting systematic information about the context and characteristics of climate-sensitive decisions and using this informatio...

[Gustometry usefulness for the evaluation of taste sense efficiency. Part I. The range of taste substances concentrations and the result of gustometry examination].

PubMed

Klimacka-Nawrot, Ewa; Suchecka, Wanda; Błońska-Fajfrowska, Barbara

2007-01-01

There are various methods of taste substances application in gustometry examination. The Polish Committee of Standards (Polski Komitet Normalizacyjny--PKN) recommends the performance of sensitivity taste examinations with the use of method based on rinsing out the mouth with water solutions of taste substances (sip-and-spit method) at their growing concentrations. The aim of the present research was to assess the usefulness of taste substances dilutions, whose concentrations were consistent with guidelines of the PKN for the evaluation of the results of examination of sweet, salty and sour taste sensitivity. 795 volunteers, i.e. 473 women and 322 men, aged 18-66, were the subject of study. The range of concentrations in sucrose solutions (0.34-12.00 g/l) as well as in sodium chloride solutions (0.16-2.00 g/l) were proper for examination in order to recognize taste threshold with the most volunteers. However, the use of concentrations in citric acid solutions (in the range 0.13-0.60 g/l) did not enable to investigate the taste sensitivity by reason of the large percentage of persons (85.2%) who correctly recognized the sour taste of the solution with the lowest citric acid concentration. The range of citric acid concentration (0.0036-0.2000 g/l) appeared to be more proper for examination of the sour taste sensitivity. The concentrations of sucrose and sodium chloride solutions recommended by PKN are proper for the examination of sweet and salty taste sensitivity with the use of sip-and-spit method however concentrations of citric acid solutions should be lower than recommended.

Downsides of an overly context-sensitive self: implications from the culture and subjective well-being research.

PubMed

Suh, Eunkook M

2007-12-01

The self becomes context sensitive in service of the need to belong. When it comes to achieving personal happiness, an identity system that derives its worth and meaning excessively from its social context puts itself in a significantly disadvantageous position. This article integrates empirical findings and ideas from the self, subjective well-being, and cross-cultural literature and tries to offer insights to why East Asian cultural members report surprisingly low levels of happiness. The various cognitive, motivational, behavioral, and affective characteristics of the overly relation-oriented self are discussed as potential explanations. Implications for the study of self and culture are offered.

Surface Adsorption in Nonpolarizable Atomic Models.

PubMed

Whitmer, Jonathan K; Joshi, Abhijeet A; Carlton, Rebecca J; Abbott, Nicholas L; de Pablo, Juan J

2014-12-09

Many ionic solutions exhibit species-dependent properties, including surface tension and the salting-out of proteins. These effects may be loosely quantified in terms of the Hofmeister series, first identified in the context of protein solubility. Here, our interest is to develop atomistic models capable of capturing Hofmeister effects rigorously. Importantly, we aim to capture this dependence in computationally cheap "hard" ionic models, which do not exhibit dynamic polarization. To do this, we have performed an investigation detailing the effects of the water model on these properties. Though incredibly important, the role of water models in simulation of ionic solutions and biological systems is essentially unexplored. We quantify this via the ion-dependent surface attraction of the halide series (Cl, Br, I) and, in so doing, determine the relative importance of various hypothesized contributions to ionic surface free energies. Importantly, we demonstrate surface adsorption can result in hard ionic models combined with a thermodynamically accurate representation of the water molecule (TIP4Q). The effect observed in simulations of iodide is commensurate with previous calculations of the surface potential of mean force in rigid molecular dynamics and polarizable density-functional models. Our calculations are direct simulation evidence of the subtle but sensitive role of water thermodynamics in atomistic simulations.

Criticality Calculations with MCNP6 - Practical Lectures

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

Brown, Forrest B.; Rising, Michael Evan; Alwin, Jennifer Louise

2016-11-29

These slides are used to teach MCNP (Monte Carlo N-Particle) usage to nuclear criticality safety analysts. The following are the lecture topics: course information, introduction, MCNP basics, criticality calculations, advanced geometry, tallies, adjoint-weighted tallies and sensitivities, physics and nuclear data, parameter studies, NCS validation I, NCS validation II, NCS validation III, case study 1 - solution tanks, case study 2 - fuel vault, case study 3 - B&W core, case study 4 - simple TRIGA, case study 5 - fissile mat. vault, criticality accident alarm systems. After completion of this course, you should be able to: Develop an input modelmore » for MCNP; Describe how cross section data impact Monte Carlo and deterministic codes; Describe the importance of validation of computer codes and how it is accomplished; Describe the methodology supporting Monte Carlo codes and deterministic codes; Describe pitfalls of Monte Carlo calculations; Discuss the strengths and weaknesses of Monte Carlo and Discrete Ordinants codes; The diffusion theory model is not strictly valid for treating fissile systems in which neutron absorption, voids, and/or material boundaries are present. In the context of these limitations, identify a fissile system for which a diffusion theory solution would be adequate.« less

Human factors issues in performing life science experiments in a 0-G environment

NASA Technical Reports Server (NTRS)

Gonzalez, Wayne

1989-01-01

An overview of the environmental conditions within the Spacelab and the planned Space Station Freedom is presented. How this environment causes specific Human Factors problems and the nature of design solutions are described. The impact of these problems and solutions on the performance of life science activities onboard Spacelab (SL) and Space Station Freedom (SSF) is discussed. The first area highlighted is contamination. The permanence of SSF in contrast to the two-week mission of SL has significant impacts on crew and specimen protection requirements and, thus, resource utilization. These requirements, in turn impose restrictions on working volumes, scheduling, training, and scope of experimental procedures. A second area is microgravity. This means that all specimens, materials, and apparatus must be restrained and carefully controlled. Because so much of the scientific activity must occur within restricted enclosures (gloveboxes), the provisions for restraint and control are made more complex. The third topic is crewmember biomechanics and the problems of movement and task performance in microgravity. In addition to the need to stabilize the body for the performance of tasks, performance of very sensitive tasks such as dissection is difficult. The issue of space sickness and adaption is considered in this context.

Preschool Children's Observed Disruptive Behavior: Variations across Sex, Interactional Context, and Disruptive Psychopathology

ERIC Educational Resources Information Center

Gray, Sarah A. O.; Carter, Alice S.; Briggs-Gowan, Margaret J.; Hill, Carri; Danis, Barbara; Keenan, Kate; Wakschlag, Lauren S.

2012-01-01

Sex differences in disruptive behavior and sensitivity to social context are documented, but the intersection between them is rarely examined empirically. This report focuses on sex differences in observed disruptive behavior across interactional contexts and diagnostic status. Preschoolers (n = 327) were classified as nondisruptive (51%),…

Production of biofuels and biomolecules in the framework of circular economy: A regional case study.

PubMed

Jacquet, Nicolas; Haubruge, Eric; Richel, Aurore

2015-12-01

Faced to the economic and energetic context of our society, it is widely recognised that an alternative to fossil fuels and oil-based products will be needed in the nearest future. In this way, development of urban biorefinery could bring many solutions to this problem. Study of the implementation of urban biorefinery highlights two sustainable configurations that provide solutions to the Walloon context by promoting niche markets, developing circular economy and reducing transport of supply feedstock. First, autonomous urban biorefineries are proposed, which use biological waste for the production of added value molecules and/or finished products and are energetically self-sufficient. Second, integrated urban biorefineries, which benefit from an energy supply from a nearby industrial activity. In the Walloon economic context, these types of urban biorefineries could provide solutions by promoting niche markets, developing a circular economy model, optimise the transport of supply feedstock and contribute to the sustainable development. © The Author(s) 2015.

Context-Aided Sensor Fusion for Enhanced Urban Navigation

PubMed Central

Martí, Enrique David; Martín, David; García, Jesús; de la Escalera, Arturo; Molina, José Manuel; Armingol, José María

2012-01-01

The deployment of Intelligent Vehicles in urban environments requires reliable estimation of positioning for urban navigation. The inherent complexity of this kind of environments fosters the development of novel systems which should provide reliable and precise solutions to the vehicle. This article details an advanced GNSS/IMU fusion system based on a context-aided Unscented Kalman filter for navigation in urban conditions. The constrained non-linear filter is here conditioned by a contextual knowledge module which reasons about sensor quality and driving context in order to adapt it to the situation, while at the same time it carries out a continuous estimation and correction of INS drift errors. An exhaustive analysis has been carried out with available data in order to characterize the behavior of available sensors and take it into account in the developed solution. The performance is then analyzed with an extensive dataset containing representative situations. The proposed solution suits the use of fusion algorithms for deploying Intelligent Transport Systems in urban environments. PMID:23223080

Context-aided sensor fusion for enhanced urban navigation.

PubMed

Martí, Enrique David; Martín, David; García, Jesús; de la Escalera, Arturo; Molina, José Manuel; Armingol, José María

2012-12-06

 The deployment of Intelligent Vehicles in urban environments requires reliable estimation of positioning for urban navigation. The inherent complexity of this kind of environments fosters the development of novel systems which should provide reliable and precise solutions to the vehicle. This article details an advanced GNSS/IMU fusion system based on a context-aided Unscented Kalman filter for navigation in urban conditions. The constrained non-linear filter is here conditioned by a contextual knowledge module which reasons about sensor quality and driving context in order to adapt it to the situation, while at the same time it carries out a continuous estimation and correction of INS drift errors. An exhaustive analysis has been carried out with available data in order to characterize the behavior of available sensors and take it into account in the developed solution. The performance is then analyzed with an extensive dataset containing representative situations. The proposed solution suits the use of fusion algorithms for deploying Intelligent Transport Systems in urban environments.

Cross Validation Through Two-Dimensional Solution Surface for Cost-Sensitive SVM.

PubMed

Gu, Bin; Sheng, Victor S; Tay, Keng Yeow; Romano, Walter; Li, Shuo

2017-06-01

Model selection plays an important role in cost-sensitive SVM (CS-SVM). It has been proven that the global minimum cross validation (CV) error can be efficiently computed based on the solution path for one parameter learning problems. However, it is a challenge to obtain the global minimum CV error for CS-SVM based on one-dimensional solution path and traditional grid search, because CS-SVM is with two regularization parameters. In this paper, we propose a solution and error surfaces based CV approach (CV-SES). More specifically, we first compute a two-dimensional solution surface for CS-SVM based on a bi-parameter space partition algorithm, which can fit solutions of CS-SVM for all values of both regularization parameters. Then, we compute a two-dimensional validation error surface for each CV fold, which can fit validation errors of CS-SVM for all values of both regularization parameters. Finally, we obtain the CV error surface by superposing K validation error surfaces, which can find the global minimum CV error of CS-SVM. Experiments are conducted on seven datasets for cost sensitive learning and on four datasets for imbalanced learning. Experimental results not only show that our proposed CV-SES has a better generalization ability than CS-SVM with various hybrids between grid search and solution path methods, and than recent proposed cost-sensitive hinge loss SVM with three-dimensional grid search, but also show that CV-SES uses less running time.

Predictors of Maternal Sensitivity in At-Risk Families

ERIC Educational Resources Information Center

Neuhauser, Alex

2018-01-01

Maternal sensitivity is of central importance to a child's healthy development. This study examines how different types of psychosocial stress originating from the child, the parents, the context, and overall stress relate to maternal sensitivity. Psychosocial stress and its impact on maternal sensitivity are assessed in an at-risk sample of 248…

Investigation of diseases through red blood cells' shape using photoacoustic response technique

NASA Astrophysics Data System (ADS)

Biswas, Deblina; Gorey, Abhijeet; Chen, Goerge C. K.; Sharma, Norman; Vasudevan, Srivathsan

2015-03-01

Photoacoustic (PA) imaging is a non-invasive real-time technique, widely applied to many biomedical imaging studies in the recent years. While most of these studies have been focussed on obtaining an image after reconstruction, various features of time domain signal (e.g. amplitude, width, rise and relaxation time) would provide very high sensitivity in detecting morphological changes in cells during a biological study. Different haematological disorders (e.g., sickle cell anaemia, thalassemia) exhibit significant morphological cellular changes. In this context, this study explores the possibility of utilizing the developed photoacoustic response technique to apply onto blood samples. Results of our preliminary study demonstrate that there is a significant change in signal amplitude due to change in concentration of the blood. Thus it shows the sensitivity of the developed photoacoustic technique towards red blood cell count (related to haematological disease like anaemia). Subsequently, morphological changes in RBC (i.e. swollen and shrunk compared to normal RBC) induced by hypotonic and hypertonic solutions respectively were also experimented. The result shows a distinct change in PA signal amplitude. This would serve as a diagnostic signature for many future studies on cellular morphological disorders.

CAreDroid: Adaptation Framework for Android Context-Aware Applications

PubMed Central

Elmalaki, Salma; Wanner, Lucas; Srivastava, Mani

2015-01-01

Context-awareness is the ability of software systems to sense and adapt to their physical environment. Many contemporary mobile applications adapt to changing locations, connectivity states, available computational and energy resources, and proximity to other users and devices. Nevertheless, there is little systematic support for context-awareness in contemporary mobile operating systems. Because of this, application developers must build their own context-awareness adaptation engines, dealing directly with sensors and polluting application code with complex adaptation decisions. In this paper, we introduce CAreDroid, which is a framework that is designed to decouple the application logic from the complex adaptation decisions in Android context-aware applications. In this framework, developers are required— only—to focus on the application logic by providing a list of methods that are sensitive to certain contexts along with the permissible operating ranges under those contexts. At run time, CAreDroid monitors the context of the physical environment and intercepts calls to sensitive methods, activating only the blocks of code that best fit the current physical context. CAreDroid is implemented as part of the Android runtime system. By pushing context monitoring and adaptation into the runtime system, CAreDroid eases the development of context-aware applications and increases their efficiency. In particular, case study applications implemented using CAre-Droid are shown to have: (1) at least half lines of code fewer and (2) at least 10× more efficient in execution time compared to equivalent context-aware applications that use only standard Android APIs. PMID:26834512

CAreDroid: Adaptation Framework for Android Context-Aware Applications.

PubMed

Elmalaki, Salma; Wanner, Lucas; Srivastava, Mani

2015-09-01

Context-awareness is the ability of software systems to sense and adapt to their physical environment. Many contemporary mobile applications adapt to changing locations, connectivity states, available computational and energy resources, and proximity to other users and devices. Nevertheless, there is little systematic support for context-awareness in contemporary mobile operating systems. Because of this, application developers must build their own context-awareness adaptation engines, dealing directly with sensors and polluting application code with complex adaptation decisions. In this paper, we introduce CAreDroid, which is a framework that is designed to decouple the application logic from the complex adaptation decisions in Android context-aware applications. In this framework, developers are required- only-to focus on the application logic by providing a list of methods that are sensitive to certain contexts along with the permissible operating ranges under those contexts. At run time, CAreDroid monitors the context of the physical environment and intercepts calls to sensitive methods, activating only the blocks of code that best fit the current physical context. CAreDroid is implemented as part of the Android runtime system. By pushing context monitoring and adaptation into the runtime system, CAreDroid eases the development of context-aware applications and increases their efficiency. In particular, case study applications implemented using CAre-Droid are shown to have: (1) at least half lines of code fewer and (2) at least 10× more efficient in execution time compared to equivalent context-aware applications that use only standard Android APIs.

Food sensitivity in reflux esophagitis.

PubMed

Price, S F; Smithson, K W; Castell, D O

1978-08-01

We examined 66 patients with pain of possible esophageal origin for sensitivity to intraesophageal infusions of coffee, orange juice, spicy tomato drink, or HCl of varying concentrations as an addendum to their acid infusion (Bernstein) tests. Compared to Berstein-negative subjects, acid-sensitive patients were sensitive to infusion of coffee (P less than 0.01), orange juice (P less than 0.001), and tomato drink (P less than 0.001). Patients were largely insensitive to HCl solutions with a titratable acidity of 1 mEq per liter or less, less than the least acidic food solution tested. However, Berstein-positive patients were still highly sensitive to infusions of coffee, orange juice, and tomato drink adjusted to pH 7 (P less than 0.001). Patients were unable to differentiate symptoms caused by acid or food infusions, and solutions did not differ in the duration of infusion needed either to cause symptoms or to relieve them by saline. We conclude that the pain of esophagitis is nonspecific and can be precipitated by variety of seemingly unrelated substances.

HgNO3 sensitivity of AlGaN/GaN field effect transistors functionalized with phytochelating peptides

NASA Astrophysics Data System (ADS)

Rohrbaugh, Nathaniel; Hernandez-Balderrama, Luis; Kaess, Felix; Kirste, Ronny; Collazo, Ramon; Ivanisevic, Albena

2016-06-01

This study examined the conductance sensitivity of AlGaN/GaN field effect transistors in response to varying Hg/HNO3 solutions. FET surfaces were covalently functionalized with phytochelatin-5 peptides in order to detect Hg in solution. Results showed a resilience of peptide-AlGaN/GaN bonds in the presence of strong HNO3 aliquots, with significant degradation in FET ID signal. However, devices showed strong and varied response to Hg concentrations of 1, 10, 100, and 1000 ppm. The gathered statistically significant results indicate that peptide terminated AlGaN/GaN devices are capable of differentiating between Hg solutions and demonstrate device sensitivity.

Biological Sensitivity to Context Moderates the Effects of the Early Teacher-Child Relationship on the Development of Mental Health by Adolescence

PubMed Central

Essex, Marilyn J.; Armstrong, Jeffrey M.; Burk, Linnea R.; Goldsmith, H. Hill; Boyce, W. Thomas

2010-01-01

The moderating effects of biological sensitivity to context (physiological and behavioral stress reactivity) on the association between the early teacher-child relationship and the development of adolescent mental health problems were examined in a community sample of 96 children. Grade 1 measures of biological sensitivity to context included physiological (i.e., slope of mean arterial pressure across a 20-30 min stress protocol) and behavioral (i.e., temperamental inhibition/disinhibition) markers. Grade 1 measures of the teacher-child relationship included positive (i.e., closeness) and negative (i.e., conflict) qualities. Mental health symptoms were assessed at Grades 1 and 7. Results of a multiple regression analysis indicated substantial association of the teacher-child relationship with the development of adolescent mental health symptoms, especially for more reactive children. In addition to teacher-child relationship main effects, all four reactivity × teacher-child relationship interaction terms were statistically significant when controlling for Grade 1 symptom severity, suggesting that both physiological and behavioral reactivity moderate the association of both adverse and supportive aspects of the teacher-child relationship with Grade 7 symptom severity over and above Grade 1 severity. There were important differences depending on which stress reactivity measure was considered. The importance of these findings for recent theoretical arguments regarding biological sensitivity to context and differential susceptibility is discussed. PMID:21262045

Biological Sensitivity to Context: The Interactive Effects of Stress Reactivity and Family Adversity on Socio-Emotional Behavior and School Readiness

PubMed Central

Obradović, Jelena; Bush, Nicole R.; Stamperdahl, Juliet; Adler, Nancy E.; Boyce, W. Thomas

2009-01-01

This study examined the direct and interactive effects of stress reactivity and family adversity on socio-emotional and cognitive development in 338 five-to-six-year-old children. Neurobiological stress reactivity was measured as respiratory sinus arrhythmia and salivary cortisol responses to social, cognitive, sensory, and emotional challenges. Adaptation was assessed using child, parent, and teacher reports of externalizing symptoms, prosocial behaviors, school engagement, and academic competence. Results revealed significant interactions between reactivity and adversity. High stress reactivity was associated with more maladaptive outcomes in the context of high adversity but with better adaption in the context of low adversity. The findings corroborate a reconceptualization of stress reactivity as biological sensitivity to context by showing that high reactivity can both hinder and promote adaptive functioning. PMID:20331667

Is he playing solo or within an ensemble? How the context, visual information, and expertise may impact upon the perception of musical expressivity.

PubMed

Glowinski, Donald; Riolfo, Arianna; Shirole, Kanika; Torres-Eliard, Kim; Chiorri, Carlo; Grandjean, Didier

2014-01-01

Visual information is imperative when developing a concrete and context-sensitive understanding of how music performance is perceived. Recent studies highlight natural, automatic, and nonconscious dependence on visual cues that ultimately refer to body expressions observed in the musician. The current study investigated how the social context of a performing musician (eg playing alone or within an ensemble) and the musical expertise of the perceivers influence the strategies used to understand and decode the visual features of music performance. Results revealed that both perceiver groups, nonmusicians and musicians, have a higher sensitivity towards gaze information; therefore, an impoverished stimulus such as a point-light display is insufficient to understand the social context in which the musician is performing. Implications for these findings are discussed.

A web-based rapid assessment tool for production publishing solutions

NASA Astrophysics Data System (ADS)

Sun, Tong

2010-02-01

Solution assessment is a critical first-step in understanding and measuring the business process efficiency enabled by an integrated solution package. However, assessing the effectiveness of any solution is usually a very expensive and timeconsuming task which involves lots of domain knowledge, collecting and understanding the specific customer operational context, defining validation scenarios and estimating the expected performance and operational cost. This paper presents an intelligent web-based tool that can rapidly assess any given solution package for production publishing workflows via a simulation engine and create a report for various estimated performance metrics (e.g. throughput, turnaround time, resource utilization) and operational cost. By integrating the digital publishing workflow ontology and an activity based costing model with a Petri-net based workflow simulation engine, this web-based tool allows users to quickly evaluate any potential digital publishing solutions side-by-side within their desired operational contexts, and provides a low-cost and rapid assessment for organizations before committing any purchase. This tool also benefits the solution providers to shorten the sales cycles, establishing a trustworthy customer relationship and supplement the professional assessment services with a proven quantitative simulation and estimation technology.

Precision of Sensitivity in the Design Optimization of Indeterminate Structures

NASA Technical Reports Server (NTRS)

Patnaik, Surya N.; Pai, Shantaram S.; Hopkins, Dale A.

2006-01-01

Design sensitivity is central to most optimization methods. The analytical sensitivity expression for an indeterminate structural design optimization problem can be factored into a simple determinate term and a complicated indeterminate component. Sensitivity can be approximated by retaining only the determinate term and setting the indeterminate factor to zero. The optimum solution is reached with the approximate sensitivity. The central processing unit (CPU) time to solution is substantially reduced. The benefit that accrues from using the approximate sensitivity is quantified by solving a set of problems in a controlled environment. Each problem is solved twice: first using the closed-form sensitivity expression, then using the approximation. The problem solutions use the CometBoards testbed as the optimization tool with the integrated force method as the analyzer. The modification that may be required, to use the stiffener method as the analysis tool in optimization, is discussed. The design optimization problem of an indeterminate structure contains many dependent constraints because of the implicit relationship between stresses, as well as the relationship between the stresses and displacements. The design optimization process can become problematic because the implicit relationship reduces the rank of the sensitivity matrix. The proposed approximation restores the full rank and enhances the robustness of the design optimization method.

Context-Dependent Repetition Effects on Recognition Memory

ERIC Educational Resources Information Center

Opitz, Bertram

2010-01-01

One widely acknowledged way to improve our memory performance is to repeatedly study the to be learned material. One aspect that has received little attention in past research regards the context sensitivity of this repetition effect, that is whether the item is repeated within the same or within different contexts. The predictions of a…

Context Sensitivity in the Force Concept Inventory

ERIC Educational Resources Information Center

Stewart, John; Griffin, Heather; Stewart, Gay

2007-01-01

The force concept inventory and a 10-question context-modified test were given to 647 students enrolled in introductory physics classes at the University of Arkansas. Context changes had an effect ranging from -3% to 10% on the individual questions. The average student score on the ten transformed questions was 3% higher than the average student…

Educational Context: Preparing Accounting Students to Identify Ethical Dilemmas

ERIC Educational Resources Information Center

Billiot, Mary Jo; Daniel, David; Glandon, Sid; Glandon, TerryAnn

2012-01-01

We examine the effect of different contexts in an educational process on measures of ethical sensitivity and levels of moral reasoning of accounting majors in the first Intermediate Accounting course. The educational process compared a context that centers on ethical issues with one that focuses on technical accounting issues. At the end of the…

A Culturally Sensitive Analysis of Culture in the Context of Context: When Is Enough Enough?

ERIC Educational Resources Information Center

Kahn, Peter H., Jr.

Cultural context is not the sole source of human knowledge. Postmodern theory, in both its deconstructionist and affirmative approaches, offers an incomplete basis by which to study race, class, and gender, and undermines ethical interaction. Deconstructionism calls for the abandonment of generalizable research findings, asserting that the concept…

Intersection of Stress, Social Disadvantage, and Life Course Processes: Reframing Trauma and Mental Health.

PubMed

Nurius, Paula S; Uehara, Edwina; Zatzick, Douglas F

2013-04-01

This paper describes the intersection of converging lines of research on the social structural, psychosocial, and physiological factors involved in the production of stress and implications for the field of mental health. Of particular interest are the stress sensitization consequences stemming from exposure to adversity over the life course. Contemporary stress sensitization theory provides important clinical utility in articulating mechanisms through which these multiple levels exert influence on mental health. Stress sensitization models (a) extend understanding of neurobiological and functional contexts within which extreme stressors operate and (b) make clear how these can influence psychologically traumatic outcomes. The value of interventions that are sensitive to current contexts as well as life course profiles of cumulative stress are illustrated through recent treatment innovations.

Intersection of Stress, Social Disadvantage, and Life Course Processes: Reframing Trauma and Mental Health

PubMed Central

Nurius, Paula S.; Uehara, Edwina; Zatzick, Douglas F.

2015-01-01

This paper describes the intersection of converging lines of research on the social structural, psychosocial, and physiological factors involved in the production of stress and implications for the field of mental health. Of particular interest are the stress sensitization consequences stemming from exposure to adversity over the life course. Contemporary stress sensitization theory provides important clinical utility in articulating mechanisms through which these multiple levels exert influence on mental health. Stress sensitization models (a) extend understanding of neurobiological and functional contexts within which extreme stressors operate and (b) make clear how these can influence psychologically traumatic outcomes. The value of interventions that are sensitive to current contexts as well as life course profiles of cumulative stress are illustrated through recent treatment innovations. PMID:25729337

Analytical approach for the fractional differential equations by using the extended tanh method

NASA Astrophysics Data System (ADS)

Pandir, Yusuf; Yildirim, Ayse

2018-07-01

In this study, we consider analytical solutions of space-time fractional derivative foam drainage equation, the nonlinear Korteweg-de Vries equation with time and space-fractional derivatives and time-fractional reaction-diffusion equation by using the extended tanh method. The fractional derivatives are defined in the modified Riemann-Liouville context. As a result, various exact analytical solutions consisting of trigonometric function solutions, kink-shaped soliton solutions and new exact solitary wave solutions are obtained.

Young Adolescents' Metacognition and Domain Knowledge as Predictors of Hypothesis-Development Performance in a Computer-Supported Context

ERIC Educational Resources Information Center

Kim, Hye Jeong; Pedersen, Susan

2010-01-01

Recently, the importance of ill-structured problem-solving in real-world contexts has become a focus of educational research. Particularly, the hypothesis-development process has been examined as one of the keys to developing a high-quality solution in a problem context. The authors of this study examined predictive relations between young…

Conditioned Taste Aversion Is Enhanced When the Unconditioned Stimulus Is Presented in a Different Context

ERIC Educational Resources Information Center

Ishii, Kiyoshi; Iguchi, Yoshio; Fukumoto, Kazuya; Nakayasu, Tomohiro

2008-01-01

Using a conditioned taste aversion procedure with rats as the subjects, two experiments examined the effect of presenting a conditioned stimulus (CS saccharin solution) in one context followed by an unconditioned stimulus (US LiCl) in a different context. Experiment 1 showed that animals which received the above-mentioned procedure (Group D)…

Context-sensitive medical information retrieval.

PubMed

Auerbuch, Mordechai; Karson, Tom H; Ben-Ami, Benjamin; Maimon, Oded; Rokach, Lior

2004-01-01

Substantial medical data such as pathology reports, operative reports, discharge summaries, and radiology reports are stored in textual form. Databases containing free-text medical narratives often need to be searched to find relevant information for clinical and research purposes. Terms that appear in these documents tend to appear in different contexts. The con-text of negation, a negative finding, is of special importance, since many of the most frequently described findings are those denied by the patient or subsequently "ruled out." Hence, when searching free-text narratives for patients with a certain medical condition, if negation is not taken into account, many of the retrieved documents will be irrelevant. The purpose of this work is to develop a methodology for automated learning of negative context patterns in medical narratives and test the effect of context identification on the performance of medical information retrieval. The algorithm presented significantly improves the performance of information retrieval done on medical narratives. The precision im-proves from about 60%, when using context-insensitive retrieval, to nearly 100%. The impact on recall is only minor. In addition, context-sensitive queries enable the user to search for terms in ways not otherwise available

Sensitivity calculations for iteratively solved problems

NASA Technical Reports Server (NTRS)

Haftka, R. T.

1985-01-01

The calculation of sensitivity derivatives of solutions of iteratively solved systems of algebraic equations is investigated. A modified finite difference procedure is presented which improves the accuracy of the calculated derivatives. The procedure is demonstrated for a simple algebraic example as well as an element-by-element preconditioned conjugate gradient iterative solution technique applied to truss examples.

Supervised detection of exoplanets in high-contrast imaging sequences

NASA Astrophysics Data System (ADS)

Gomez Gonzalez, C. A.; Absil, O.; Van Droogenbroeck, M.

2018-06-01

Context. Post-processing algorithms play a key role in pushing the detection limits of high-contrast imaging (HCI) instruments. State-of-the-art image processing approaches for HCI enable the production of science-ready images relying on unsupervised learning techniques, such as low-rank approximations, for generating a model point spread function (PSF) and subtracting the residual starlight and speckle noise. Aims: In order to maximize the detection rate of HCI instruments and survey campaigns, advanced algorithms with higher sensitivities to faint companions are needed, especially for the speckle-dominated innermost region of the images. Methods: We propose a reformulation of the exoplanet detection task (for ADI sequences) that builds on well-established machine learning techniques to take HCI post-processing from an unsupervised to a supervised learning context. In this new framework, we present algorithmic solutions using two different discriminative models: SODIRF (random forests) and SODINN (neural networks). We test these algorithms on real ADI datasets from VLT/NACO and VLT/SPHERE HCI instruments. We then assess their performances by injecting fake companions and using receiver operating characteristic analysis. This is done in comparison with state-of-the-art ADI algorithms, such as ADI principal component analysis (ADI-PCA). Results: This study shows the improved sensitivity versus specificity trade-off of the proposed supervised detection approach. At the diffraction limit, SODINN improves the true positive rate by a factor ranging from 2 to 10 (depending on the dataset and angular separation) with respect to ADI-PCA when working at the same false-positive level. Conclusions: The proposed supervised detection framework outperforms state-of-the-art techniques in the task of discriminating planet signal from speckles. In addition, it offers the possibility of re-processing existing HCI databases to maximize their scientific return and potentially improve the demographics of directly imaged exoplanets.

(Un)doing gender in a rehabilitation context: a narrative analysis of gender and self in stories of chronic muscle pain.

PubMed

Ahlsen, Birgitte; Bondevik, Hilde; Mengshoel, Anne Marit; Solbrække, Kari Nyheim

2014-01-01

To explore how gender appears in the stories of self-told by men and women undergoing rehabilitation for chronic muscle pain. The material, which consists of qualitative interviews with 10 men and 6 women with chronic neck pain, was analyzed from a gender sensitive perspective using narrative method. The analysis was inspired by Arthur Frank's typologies of illness narratives (restitution, chaos and quest). The women's stories displayed selves that were actively trying to transcend their former identity and life conditions, in which their pain was embedded. Their stories tended to develop from "chaos", towards a quest narrative with a more autonomous self. The selves in the men's stories appeared to be actively seeking a solution to the pain within a medical context. Framed as a restitution narrative, rooted in a biomedical model of disease, the voice often heard in the men's stories was of a self-dependent on future health care. Our findings contribute greater nuance to a dominant cultural conception that men are more independent than women in relation to health care. Understanding the significance of gender in the construction of selves in stories of chronic pain may help to improve the health care offered to patients suffering from chronic pain. Implications for Rehabilitation Patients tell stories that powerfully communicate their particular illness experiences. Cultural expectations of femininity and masculinity play a significant role with regard to how the patients construct their stories, which may be important to health professionals' perceptions of the patients' problem. Health care professionals should listen carefully to the patient's own story and be sensitive to the significance of gender when trying to understand these people's health problem.

Pharmacological Targeting of the Host-Pathogen Interaction: Alternatives to Classical Antibiotics to Combat Drug-Resistant Superbugs.

PubMed

Munguia, Jason; Nizet, Victor

2017-05-01

The rise of multidrug-resistant pathogens and the dearth of new antibiotic development place an existential strain on successful infectious disease therapy. Breakthrough strategies that go beyond classical antibiotic mechanisms are needed to combat this looming public health catastrophe. Reconceptualizing antibiotic therapy in the richer context of the host-pathogen interaction is required for innovative solutions. By defining specific virulence factors, the essence of a pathogen, and pharmacologically neutralizing their activities, one can block disease progression and sensitize microbes to immune clearance. Likewise, host-directed strategies to boost phagocyte bactericidal activity, enhance leukocyte recruitment, or reverse pathogen-induced immunosuppression seek to replicate the success of cancer immunotherapy in the field of infectious diseases. The answer to the threat of multidrug-resistant pathogens lies 'outside the box' of current antibiotic paradigms. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Cluster-Based Framework for the Security of Medical Sensor Environments

NASA Astrophysics Data System (ADS)

Klaoudatou, Eleni; Konstantinou, Elisavet; Kambourakis, Georgios; Gritzalis, Stefanos

The adoption of Wireless Sensor Networks (WSNs) in the healthcare sector poses many security issues, mainly because medical information is considered particularly sensitive. The security mechanisms employed are expected to be more efficient in terms of energy consumption and scalability in order to cope with the constrained capabilities of WSNs and patients’ mobility. Towards this goal, cluster-based medical WSNs can substantially improve efficiency and scalability. In this context, we have proposed a general framework for cluster-based medical environments on top of which security mechanisms can rely. This framework fully covers the varying needs of both in-hospital environments and environments formed ad hoc for medical emergencies. In this paper, we further elaborate on the security of our proposed solution. We specifically focus on key establishment mechanisms and investigate the group key agreement protocols that can best fit in our framework.

Teaching cultural diversity: current status in U.K., U.S., and Canadian medical schools.

PubMed

Dogra, Nisha; Reitmanova, Sylvia; Carter-Pokras, Olivia

2010-05-01

In this paper we present the current state of cultural diversity education for undergraduate medical students in three English-speaking countries: the United Kingdom (U.K.), United States (U.S.) and Canada. We review key documents that have shaped cultural diversity education in each country and compare and contrast current issues. It is beyond the scope of this paper to discuss the varied terminology that is immediately evident. Suffice it to say that there are many terms (e.g. cultural awareness, competence, sensitivity, sensibility, diversity and critical cultural diversity) used in different contexts with different meanings. The major issues that all three countries face include a lack of conceptual clarity, and fragmented and variable programs to teach cultural diversity. Faculty and staff support and development, and ambivalence from both staff and students continue to be a challenge. We suggest that greater international collaboration may help provide some solutions.

Simulation of Mechanical Behavior and Damage of a Large Composite Wind Turbine Blade under Critical Loads

NASA Astrophysics Data System (ADS)

Tarfaoui, M.; Nachtane, M.; Khadimallah, H.; Saifaoui, D.

2018-04-01

Issues such as energy generation/transmission and greenhouse gas emissions are the two energy problems we face today. In this context, renewable energy sources are a necessary part of the solution essentially winds power, which is one of the most profitable sources of competition with new fossil energy facilities. This paper present the simulation of mechanical behavior and damage of a 48 m composite wind turbine blade under critical wind loads. The finite element analysis was performed by using ABAQUS code to predict the most critical damage behavior and to apprehend and obtain knowledge of the complex structural behavior of wind turbine blades. The approach developed based on the nonlinear FE analysis using mean values for the material properties and the failure criteria of Tsai-Hill to predict failure modes in large structures and to identify the sensitive zones.

Electrochemical biosensors for Salmonella: State of the art and challenges in food safety assessment.

PubMed

Silva, Nádia F D; Magalhães, Júlia M C S; Freire, Cristina; Delerue-Matos, Cristina

2018-01-15

According to the recent statistics, Salmonella is still an important public health issue in the whole world. Legislated reference methods, based on counting plate methods, are sensitive enough but are inadequate as an effective emergency response tool, and are far from a rapid device, simple to use out of lab. An overview of the commercially available rapid methods for Salmonella detection is provided along with a critical discussion of their limitations, benefits and potential use in a real context. The distinguished potentialities of electrochemical biosensors for the development of rapid devices are highlighted. The state-of-art and the newest technologic approaches in electrochemical biosensors for Salmonella detection are presented and a critical analysis of the literature is made in an attempt to identify the current challenges towards a complete solution for Salmonella detection in microbial food control based on electrochemical biosensors. Copyright © 2017 Elsevier B.V. All rights reserved.

Simple energy balance model resolving the seasons and the continents - Application to the astronomical theory of the ice ages

NASA Technical Reports Server (NTRS)

North, G. R.; Short, D. A.; Mengel, J. G.

1983-01-01

An analysis is undertaken of the properties of a one-level seasonal energy balance climate model having explicit, two-dimensional land-sea geography, where land and sea surfaces are strictly distinguished by the local thermal inertia employed and transport is governed by a smooth, latitude-dependent diffusion mechanism. Solutions of the seasonal cycle for the cases of both ice feedback exclusion and inclusion yield good agreements with real data, using minimal turning of the adjustable parameters. Discontinuous icecap growth is noted for both a solar constant that is lower by a few percent and a change of orbital elements to favor cool Northern Hemisphere summers. This discontinuous sensitivity is discussed in the context of the Milankovitch theory of the ice ages, and the associated branch structure is shown to be analogous to the 'small ice cap' instability of simpler models.

Capturing Structural Heterogeneity in Chromatin Fibers.

PubMed

Ekundayo, Babatunde; Richmond, Timothy J; Schalch, Thomas

2017-10-13

Chromatin fiber organization is implicated in processes such as transcription, DNA repair and chromosome segregation, but how nucleosomes interact to form higher-order structure remains poorly understood. We solved two crystal structures of tetranucleosomes with approximately 11-bp DNA linker length at 5.8 and 6.7 Å resolution. Minimal intramolecular nucleosome-nucleosome interactions result in a fiber model resembling a flat ribbon that is compatible with a two-start helical architecture, and that exposes histone and DNA surfaces to the environment. The differences in the two structures combined with electron microscopy reveal heterogeneous structural states, and we used site-specific chemical crosslinking to assess the diversity of nucleosome-nucleosome interactions through identification of structure-sensitive crosslink sites that provide a means to characterize fibers in solution. The chromatin fiber architectures observed here provide a basis for understanding heterogeneous chromatin higher-order structures as they occur in a genomic context. Copyright © 2017 Elsevier Ltd. All rights reserved.

Iron line spectroscopy with Einstein-dilaton-Gauss-Bonnet black holes

NASA Astrophysics Data System (ADS)

Nampalliwar, Sourabh; Bambi, Cosimo; Kokkotas, Kostas D.; Konoplya, Roman A.

2018-06-01

Einstein-dilaton-Gauss-Bonnet gravity is a well-motivated alternative theory of gravity that emerges naturally from string theory. While black hole solutions have been known in this theory in numerical form for a while, an approximate analytical metric was obtained recently by some of us, which allows for faster and more detailed analysis. Here we test the accuracy of the analytical metric in the context of X-ray reflection spectroscopy. We analyze innermost stable circular orbits (ISCO) and relativistically broadened iron lines and find that both the ISCO and iron lines are determined sufficiently accurately up to the limit of the approximation. We also find that, though the ISCO increases by about 7% as dilaton coupling increases from zero to extremal values, the redshift at ISCO changes by less than 1%. Consequently, the shape of the iron line is much less sensitive to the dilaton charge than expected.

ISFET pH Sensitivity: Counter-Ions Play a Key Role.

PubMed

Parizi, Kokab B; Xu, Xiaoqing; Pal, Ashish; Hu, Xiaolin; Wong, H S Philip

2017-02-02

The Field Effect sensors are broadly used for detecting various target analytes in chemical and biological solutions. We report the conditions under which the pH sensitivity of an Ion Sensitive Field Effect transistor (ISFET) sensor can be significantly enhanced. Our theory and simulations show that by using pH buffer solutions containing counter-ions that are beyond a specific size, the sensor shows significantly higher sensitivity which can exceed the Nernst limit. We validate the theory by measuring the pH response of an extended gate ISFET pH sensor. The consistency and reproducibility of the measurement results have been recorded in hysteresis free and stable operations. Different conditions have been tested to confirm the accuracy and validity of our experiment results such as using different solutions, various oxide dielectrics as the sensing layer and off-the-shelf versus IC fabricated transistors as the basis of the ISFET sensor.

ISFET pH Sensitivity: Counter-Ions Play a Key Role

PubMed Central

Parizi, Kokab B.; Xu, Xiaoqing; Pal, Ashish; Hu, Xiaolin; Wong, H. S. Philip

2017-01-01

The Field Effect sensors are broadly used for detecting various target analytes in chemical and biological solutions. We report the conditions under which the pH sensitivity of an Ion Sensitive Field Effect transistor (ISFET) sensor can be significantly enhanced. Our theory and simulations show that by using pH buffer solutions containing counter-ions that are beyond a specific size, the sensor shows significantly higher sensitivity which can exceed the Nernst limit. We validate the theory by measuring the pH response of an extended gate ISFET pH sensor. The consistency and reproducibility of the measurement results have been recorded in hysteresis free and stable operations. Different conditions have been tested to confirm the accuracy and validity of our experiment results such as using different solutions, various oxide dielectrics as the sensing layer and off-the-shelf versus IC fabricated transistors as the basis of the ISFET sensor. PMID:28150700

Systematic evaluation of three different commercial software solutions for automatic segmentation for adaptive therapy in head-and-neck, prostate and pleural cancer.

PubMed

La Macchia, Mariangela; Fellin, Francesco; Amichetti, Maurizio; Cianchetti, Marco; Gianolini, Stefano; Paola, Vitali; Lomax, Antony J; Widesott, Lamberto

2012-09-18

To validate, in the context of adaptive radiotherapy, three commercial software solutions for atlas-based segmentation. Fifteen patients, five for each group, with cancer of the Head&Neck, pleura, and prostate were enrolled in the study. In addition to the treatment planning CT (pCT) images, one replanning CT (rCT) image set was acquired for each patient during the RT course. Three experienced physicians outlined on the pCT and rCT all the volumes of interest (VOIs). We used three software solutions (VelocityAI 2.6.2 (V), MIM 5.1.1 (M) by MIMVista and ABAS 2.0 (A) by CMS-Elekta) to generate the automatic contouring on the repeated CT. All the VOIs obtained with automatic contouring (AC) were successively corrected manually. We recorded the time needed for: 1) ex novo ROIs definition on rCT; 2) generation of AC by the three software solutions; 3) manual correction of AC.To compare the quality of the volumes obtained automatically by the software and manually corrected with those drawn from scratch on rCT, we used the following indexes: overlap coefficient (DICE), sensitivity, inclusiveness index, difference in volume, and displacement differences on three axes (x, y, z) from the isocenter. The time saved by the three software solutions for all the sites, compared to the manual contouring from scratch, is statistically significant and similar for all the three software solutions. The time saved for each site are as follows: about an hour for Head&Neck, about 40 minutes for prostate, and about 20 minutes for mesothelioma. The best DICE similarity coefficient index was obtained with the manual correction for: A (contours for prostate), A and M (contours for H&N), and M (contours for mesothelioma). From a clinical point of view, the automated contouring workflow was shown to be significantly shorter than the manual contouring process, even though manual correction of the VOIs is always needed.

Examining the Preparatory Effects of Problem Generation and Solution Generation on Learning from Instruction

ERIC Educational Resources Information Center

Kapur, Manu

2018-01-01

The goal of this paper is to isolate the preparatory effects of problem-generation from solution generation in problem-posing contexts, and their underlying mechanisms on learning from instruction. Using a randomized-controlled design, students were assigned to one of two conditions: (a) problem-posing with solution generation, where they…

New integrable models and analytical solutions in f (R ) cosmology with an ideal gas

NASA Astrophysics Data System (ADS)

Papagiannopoulos, G.; Basilakos, Spyros; Barrow, John D.; Paliathanasis, Andronikos

2018-01-01

In the context of f (R ) gravity with a spatially flat FLRW metric containing an ideal fluid, we use the method of invariant transformations to specify families of models which are integrable. We find three families of f (R ) theories for which new analytical solutions are given and closed-form solutions are provided.

Measuring Intercultural Sensitivity in Different Cultural Context.

ERIC Educational Resources Information Center

Fritz, Wolfgang; Mollenberg, Antje; Chen, Guo-Ming

As a main dimension of intercultural communication competence, intercultural sensitivity has increasingly gained attention in research in different disciplines. In the United States, Chen and Starosta (1996) developed an instrument, comprising 5 factors with 24 items, for measuring intercultural sensitivity. In this study, Chen and Starosta's…

Causal knowledge and the development of inductive reasoning.

PubMed

Bright, Aimée K; Feeney, Aidan

2014-06-01

We explored the development of sensitivity to causal relations in children's inductive reasoning. Children (5-, 8-, and 12-year-olds) and adults were given trials in which they decided whether a property known to be possessed by members of one category was also possessed by members of (a) a taxonomically related category or (b) a causally related category. The direction of the causal link was either predictive (prey→predator) or diagnostic (predator→prey), and the property that participants reasoned about established either a taxonomic or causal context. There was a causal asymmetry effect across all age groups, with more causal choices when the causal link was predictive than when it was diagnostic. Furthermore, context-sensitive causal reasoning showed a curvilinear development, with causal choices being most frequent for 8-year-olds regardless of context. Causal inductions decreased thereafter because 12-year-olds and adults made more taxonomic choices when reasoning in the taxonomic context. These findings suggest that simple causal relations may often be the default knowledge structure in young children's inductive reasoning, that sensitivity to causal direction is present early on, and that children over-generalize their causal knowledge when reasoning. Copyright © 2013 Elsevier Inc. All rights reserved.

Sensitivity analysis of dynamic biological systems with time-delays.

PubMed

Wu, Wu Hsiung; Wang, Feng Sheng; Chang, Maw Shang

2010-10-15

Mathematical modeling has been applied to the study and analysis of complex biological systems for a long time. Some processes in biological systems, such as the gene expression and feedback control in signal transduction networks, involve a time delay. These systems are represented as delay differential equation (DDE) models. Numerical sensitivity analysis of a DDE model by the direct method requires the solutions of model and sensitivity equations with time-delays. The major effort is the computation of Jacobian matrix when computing the solution of sensitivity equations. The computation of partial derivatives of complex equations either by the analytic method or by symbolic manipulation is time consuming, inconvenient, and prone to introduce human errors. To address this problem, an automatic approach to obtain the derivatives of complex functions efficiently and accurately is necessary. We have proposed an efficient algorithm with an adaptive step size control to compute the solution and dynamic sensitivities of biological systems described by ordinal differential equations (ODEs). The adaptive direct-decoupled algorithm is extended to solve the solution and dynamic sensitivities of time-delay systems describing by DDEs. To save the human effort and avoid the human errors in the computation of partial derivatives, an automatic differentiation technique is embedded in the extended algorithm to evaluate the Jacobian matrix. The extended algorithm is implemented and applied to two realistic models with time-delays: the cardiovascular control system and the TNF-α signal transduction network. The results show that the extended algorithm is a good tool for dynamic sensitivity analysis on DDE models with less user intervention. By comparing with direct-coupled methods in theory, the extended algorithm is efficient, accurate, and easy to use for end users without programming background to do dynamic sensitivity analysis on complex biological systems with time-delays.

Through the Lens of Cultural Awareness: A Primer for US Armed Forces Deploying to Arab and Middle Eastern Countries

DTIC Science & Technology

2006-01-01

Willingness to Compromise •Risk Avoidance •Time to Decision •Etc. The “What” ral Variation Behaviors •Context Sensitivity Values •Individualism vs ...Collectivism •Power Distance •Formality vs . informality •Uncertainty Avoidance •Relationship vs . Deal Focus •Long-term vs . Short term orientation •Time...Orientation Cognition •Reasoning Styles Cultural Variations Behaviors •Context Sensitivity Values •Individualism vs . Collectivism •Power Distance •Formality

Behavior of sensitivities in the one-dimensional advection-dispersion equation: Implications for parameter estimation and sampling design

USGS Publications Warehouse

Knopman, Debra S.; Voss, Clifford I.

1987-01-01

The spatial and temporal variability of sensitivities has a significant impact on parameter estimation and sampling design for studies of solute transport in porous media. Physical insight into the behavior of sensitivities is offered through an analysis of analytically derived sensitivities for the one-dimensional form of the advection-dispersion equation. When parameters are estimated in regression models of one-dimensional transport, the spatial and temporal variability in sensitivities influences variance and covariance of parameter estimates. Several principles account for the observed influence of sensitivities on parameter uncertainty. (1) Information about a physical parameter may be most accurately gained at points in space and time with a high sensitivity to the parameter. (2) As the distance of observation points from the upstream boundary increases, maximum sensitivity to velocity during passage of the solute front increases and the consequent estimate of velocity tends to have lower variance. (3) The frequency of sampling must be “in phase” with the S shape of the dispersion sensitivity curve to yield the most information on dispersion. (4) The sensitivity to the dispersion coefficient is usually at least an order of magnitude less than the sensitivity to velocity. (5) The assumed probability distribution of random error in observations of solute concentration determines the form of the sensitivities. (6) If variance in random error in observations is large, trends in sensitivities of observation points may be obscured by noise and thus have limited value in predicting variance in parameter estimates among designs. (7) Designs that minimize the variance of one parameter may not necessarily minimize the variance of other parameters. (8) The time and space interval over which an observation point is sensitive to a given parameter depends on the actual values of the parameters in the underlying physical system.

Effect of the co-sensitization sequence on the performance of dye-sensitized solar cells with porphyrin and organic dyes.

PubMed

Fan, Suhua; Lu, Xuefeng; Sun, Hong; Zhou, Gang; Chang, Yuan Jay; Wang, Zhong-Sheng

2016-01-14

To obtain a broad spectral response in the visible region, TiO2 film is co-sensitized with a porphyrin dye (FNE57 or FNE59) and an organic dye (FNE46). It is found that the stepwise co-sensitization in one single dye solution followed by in another single dye solution is better than the co-sensitization in a cocktail solution in terms of photovoltaic performance. The stepwise co-sensitization first with a porphyrin dye and then with an organic dye outperforms that in a reverse order. DSSC devices based on co-sensitizers FNE57 + FNE46 and FNE59 + FNE46 with a quasi-solid-state gel electrolyte generate power conversion efficiencies of 7.88% and 8.14%, respectively, which exhibits remarkable efficiency improvements of 61% and 35%, as compared with devices sensitized with the porphyrin dyes FNE57 and FNE59, respectively. Co-sensitization brings about a much improved short-circuit photocurrent due to the complementary absorption of the two sensitizers. The observed enhancement of incident monochromatic photon-to-electron conversion efficiency from individual dye sensitization to co-sensitization is attributed to the improved charge collection efficiency rather than to the light harvesting efficiency. Interestingly, the open-circuit photovoltage for the co-sensitization system comes between the higher voltage for the porphyrin dye (FNE57 or FNE59) and the lower voltage for the organic dye (FNE46), which is well correlated with their electron lifetimes. This finding indicates that not only the spectral complementation but also the electron lifetime should be considered to select dyes for co-sensitization.

Post-Optimality Analysis In Aerospace Vehicle Design

NASA Technical Reports Server (NTRS)

Braun, Robert D.; Kroo, Ilan M.; Gage, Peter J.

1993-01-01

This analysis pertains to the applicability of optimal sensitivity information to aerospace vehicle design. An optimal sensitivity (or post-optimality) analysis refers to computations performed once the initial optimization problem is solved. These computations may be used to characterize the design space about the present solution and infer changes in this solution as a result of constraint or parameter variations, without reoptimizing the entire system. The present analysis demonstrates that post-optimality information generated through first-order computations can be used to accurately predict the effect of constraint and parameter perturbations on the optimal solution. This assessment is based on the solution of an aircraft design problem in which the post-optimality estimates are shown to be within a few percent of the true solution over the practical range of constraint and parameter variations. Through solution of a reusable, single-stage-to-orbit, launch vehicle design problem, this optimal sensitivity information is also shown to improve the efficiency of the design process, For a hierarchically decomposed problem, this computational efficiency is realized by estimating the main-problem objective gradient through optimal sep&ivity calculations, By reducing the need for finite differentiation of a re-optimized subproblem, a significant decrease in the number of objective function evaluations required to reach the optimal solution is obtained.

Context Aware Programmable Trackers for the Next Generation Internet

NASA Astrophysics Data System (ADS)

Sousa, Pedro

This work introduces and proposes the concept of context aware programmable trackers for the next generation Internet. The proposed solution gives ground for the development of advanced applications based on the P2P paradigm and will foster collaborative efforts among several network entities (e.g. P2P applications and ISPs). The proposed concept of context aware programmable trackers allows that several peer selection strategies might be supported by a P2P tracker entity able to improve the peer selection decisions according with pre-defined objectives and external inputs provided by specific services. The flexible, adaptive and enhanced peer selection semantics that might be achieved by the proposed solution will contribute for devising novel P2P based services and business models for the future Internet.

Educational Leadership and Context: A Rendering of an Inseparable Relationship

ERIC Educational Resources Information Center

Clarke, Simon; O'Donoghue, Tom

2017-01-01

The amount of empirical research on leadership of educational organisations, and especially of schools, which has stressed the importance of being sensitive to context, is not great. This paper seeks to highlight the challenge presented by this situation. First, context is defined. Second, attention is drawn to what can be learned in the area of…

Temporal context processing within hippocampal subfields.

PubMed

Wang, Fang; Diana, Rachel A

2016-07-01

The episodic memory system can differentiate similar events based on the temporal information associated with the events. Temporal context, which is at least partially determined by the events that precede or follow the critical event, may be a cue to differentiate events. The purpose of the present study is to investigate whether the hippocampal dentate gyrus (DG)/CA3 and CA1 subfields are sensitive to changes in temporal context and, if so, whether the subregions show a linear or threshold-like response to similar temporal contexts. Participants incidentally encoded a series of object picture triplets and 20 of them were included in final analyses. The third picture in each triplet was operationally defined as the target and the first two pictures served as temporal context for the target picture. Each target picture was presented twice with temporal context manipulated to be either repeated, high similarity, low similarity, or new on the second presentation. We extracted beta parameters for the repeated target as a function of the type of temporal context. We expected to see repetition suppression, a reduction in the beta values, in response to repetition of the target. If temporal context information is included in the representation of the target within a given region, this repetition suppression should be greater for target images that were preceded by their original context than for target images preceded by a new context. Neuroimaging results showed that CA1, but not DG/CA3, modifies the target's representation based on its temporal context. Right CA1 did not distinguish high similarity temporal context from repeated context but did distinguish low similarity temporal context from repeated context. These results indicate that CA1 is sensitive to temporal context and suggest that it does not differentiate between a substantially similar temporal context and an identical temporal context. In contrast, DG/CA3 does not appear to process temporal context as defined in the current experiment. Copyright © 2016 Elsevier Inc. All rights reserved.

Prenatal choline availability alters the context sensitivity of Pavlovian conditioning in adult rats

PubMed Central

Lamoureux, Jeffrey A.; Meck, Warren H.; Williams, Christina L.

2008-01-01

The effects of prenatal choline availability on Pavlovian conditioning were assessed in adult male rats (3–4 mo). Neither supplementation nor deprivation of prenatal choline affected the acquisition and extinction of simple Pavlovian conditioned excitation, or the acquisition and retardation of conditioned inhibition. However, prenatal choline availability significantly altered the contextual control of these learned behaviors. Both control and choline-deprived rats exhibited context specificity of conditioned excitation as exhibited by a loss in responding when tested in an alternate context after conditioning; in contrast, choline-supplemented rats showed no such effect. When switched to a different context following extinction, however, both choline-supplemented and control rats showed substantial contextual control of responding, whereas choline-deficient rats did not. These data support the view that configural associations that rely on hippocampal function are selectively sensitive to prenatal manipulations of dietary choline during prenatal development. PMID:19050158

Sensitivity to Landscape Features: A Spatial Analysis of Field Geoscientists on the Move

ERIC Educational Resources Information Center

Baker, Kathleen M.; Petcovic, L. Heather

2016-01-01

Intelligent behavior in everyday contexts may depend on both ability and an individual's disposition toward using that ability. Research into patterns of thinking has identified three logically distinct components necessary for dispositional behavior: ability, inclination, and sensitivity. Surprisingly, sensitivity appears to be the most common…

Sensitivity of resource selection and connectivity models to landscape definition

Treesearch

Katherine A. Zeller; Kevin McGarigal; Samuel A. Cushman; Paul Beier; T. Winston Vickers; Walter M. Boyce

2017-01-01

Context: The definition of the geospatial landscape is the underlying basis for species-habitat models, yet sensitivity of habitat use inference, predicted probability surfaces, and connectivity models to landscape definition has received little attention. Objectives: We evaluated the sensitivity of resource selection and connectivity models to four landscape...

Revisiting the role of language in spatial cognition: Categorical perception of spatial relations in English and Korean speakers.

PubMed

Holmes, Kevin J; Moty, Kelsey; Regier, Terry

2017-12-01

The spatial relation of support has been regarded as universally privileged in nonlinguistic cognition and immune to the influence of language. English, but not Korean, obligatorily distinguishes support from nonsupport via basic spatial terms. Despite this linguistic difference, previous research suggests that English and Korean speakers show comparable nonlinguistic sensitivity to the support/nonsupport distinction. Here, using a paradigm previously found to elicit cross-language differences in color discrimination, we provide evidence for a difference in sensitivity to support/nonsupport between native English speakers and native Korean speakers who were late English learners and tested in a context that privileged Korean. Whereas the former group showed categorical perception (CP) when discriminating spatial scenes capturing the support/nonsupport distinction, the latter did not. An additional group of native Korean speakers-relatively early English learners tested in an English-salient context-patterned with the native English speakers in showing CP for support/nonsupport. These findings suggest that obligatory marking of support/nonsupport in one's native language can affect nonlinguistic sensitivity to this distinction, contra earlier findings, but that such sensitivity may also depend on aspects of language background and the immediate linguistic context.

Re-thinking the role of motor cortex: Context-sensitive motor outputs?

PubMed Central

Gandolla, Marta; Ferrante, Simona; Molteni, Franco; Guanziroli, Eleonora; Frattini, Tiziano; Martegani, Alberto; Ferrigno, Giancarlo; Friston, Karl; Pedrocchi, Alessandra; Ward, Nick S.

2014-01-01

The standard account of motor control considers descending outputs from primary motor cortex (M1) as motor commands and efference copy. This account has been challenged recently by an alternative formulation in terms of active inference: M1 is considered as part of a sensorimotor hierarchy providing top–down proprioceptive predictions. The key difference between these accounts is that predictions are sensitive to the current proprioceptive context, whereas efference copy is not. Using functional electric stimulation to experimentally manipulate proprioception during voluntary movement in healthy human subjects, we assessed the evidence for context sensitive output from M1. Dynamic causal modeling of functional magnetic resonance imaging responses showed that FES altered proprioception increased the influence of M1 on primary somatosensory cortex (S1). These results disambiguate competing accounts of motor control, provide some insight into the synaptic mechanisms of sensory attenuation and may speak to potential mechanisms of action of FES in promoting motor learning in neurorehabilitation. PMID:24440530

Re-thinking the role of motor cortex: context-sensitive motor outputs?

PubMed

Gandolla, Marta; Ferrante, Simona; Molteni, Franco; Guanziroli, Eleonora; Frattini, Tiziano; Martegani, Alberto; Ferrigno, Giancarlo; Friston, Karl; Pedrocchi, Alessandra; Ward, Nick S

2014-05-01

The standard account of motor control considers descending outputs from primary motor cortex (M1) as motor commands and efference copy. This account has been challenged recently by an alternative formulation in terms of active inference: M1 is considered as part of a sensorimotor hierarchy providing top-down proprioceptive predictions. The key difference between these accounts is that predictions are sensitive to the current proprioceptive context, whereas efference copy is not. Using functional electric stimulation to experimentally manipulate proprioception during voluntary movement in healthy human subjects, we assessed the evidence for context sensitive output from M1. Dynamic causal modeling of functional magnetic resonance imaging responses showed that FES altered proprioception increased the influence of M1 on primary somatosensory cortex (S1). These results disambiguate competing accounts of motor control, provide some insight into the synaptic mechanisms of sensory attenuation and may speak to potential mechanisms of action of FES in promoting motor learning in neurorehabilitation. Copyright © 2014 unknown. Published by Elsevier Inc. All rights reserved.

Intensity of Multilingual Language Use Predicts Cognitive Performance in Some Multilingual Older Adults

PubMed Central

Keijzer, Merel; de Bot, Kees

2018-01-01

Cognitive advantages for bilinguals have inconsistently been observed in different populations, with different operationalisations of bilingualism, cognitive performance, and the process by which language control transfers to cognitive control. This calls for studies investigating which aspects of multilingualism drive a cognitive advantage, in which populations and under which conditions. This study reports on two cognitive tasks coupled with an extensive background questionnaire on health, wellbeing, personality, language knowledge and language use, administered to 387 older adults in the northern Netherlands, a small but highly multilingual area. Using linear mixed effects regression modeling, we find that when different languages are used frequently in different contexts, enhanced attentional control is observed. Subsequently, a PLS regression model targeting also other influential factors yielded a two-component solution whereby only more sensitive measures of language proficiency and language usage in different social contexts were predictive of cognitive performance above and beyond the contribution of age, gender, income and education. We discuss these findings in light of previous studies that try to uncover more about the nature of bilingualism and the cognitive processes that may drive an advantage. With an unusually large sample size our study advocates for a move away from dichotomous, knowledge-based operationalisations of multilingualism and offers new insights for future studies at the individual level. PMID:29783764

Resonator graphene microfluidic antenna (RGMA) for blood glucose detection

NASA Astrophysics Data System (ADS)

Jizat, Noorlindawaty Md.; Mohamad, Su Natasha; Ishak, Muhammad Ikman

2017-09-01

Graphene is capable of highly sensitive analyte detection due to its nanoscale nature. Here we show a resonator graphene microfluidic antenna (RGMA) is used to detect the dielectric properties of aqueous glucose solution which represent the glucose level in blood. Simulation verified the high sensitivity of proposed RGMA made with aqueous glucose solutions at different concentrations. The RGMA yielded a sensor sensitivity of 0.1882GHz/mgml-1 as plotted from the slope of the linear fit from the result averages in S11 and S21 parameter, respectively. This results indicate that the proposed resonator antenna achieves high sensitivity and linear to the changes of glucose concentration.

Eigenvalue Contributon Estimator for Sensitivity Calculations with TSUNAMI-3D

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

Rearden, Bradley T; Williams, Mark L

2007-01-01

Since the release of the Tools for Sensitivity and Uncertainty Analysis Methodology Implementation (TSUNAMI) codes in SCALE [1], the use of sensitivity and uncertainty analysis techniques for criticality safety applications has greatly increased within the user community. In general, sensitivity and uncertainty analysis is transitioning from a technique used only by specialists to a practical tool in routine use. With the desire to use the tool more routinely comes the need to improve the solution methodology to reduce the input and computational burden on the user. This paper reviews the current solution methodology of the Monte Carlo eigenvalue sensitivity analysismore » sequence TSUNAMI-3D, describes an alternative approach, and presents results from both methodologies.« less

A complementary set of electrochemical and X-ray synchrotron techniques to determine the passivation mechanism of iron treated in a new corrosion inhibitor solution specifically developed for the preservation of metallic artefacts

NASA Astrophysics Data System (ADS)

Mirambet, F.; Reguer, S.; Rocca, E.; Hollner, S.; Testemale, D.

2010-05-01

Metallic artefacts of the cultural heritage are often stored in uncontrolled environmental conditions. They are very sensitive to atmospheric corrosion caused by a succession of wet and dry periods due to variations of relative humidity and temperature. To avoid the complete degradation of the metallic artefacts, new preventive strategies must be developed. In this context, we have studied new compounds based on sodium carboxylates solutions CH3(CH2) n-2COO-, Na+ hereafter called NaC n . They allow the formation of a passive layer at the metallic surface composed of a metal-carboxylate complex. To understand the action of those inhibitors in the passivation process of iron we have performed electrochemical measurements and surface characterisation. Moreover, to monitor in real time the growth of the coating, in situ X-ray absorption spectroscopy (XAS) experiments at iron K-edge were carried out in an electrochemical cell. These analyses have shown that in the case of NaC10 solution, the protection of iron surface is correlated to the precipitation of a well-organised layer of FeC10. These experiments confirmed that this compound is a fully oxidised trinuclear Fe(III) complex containing decanoate anions as ligands. Such information concerning the passive layer is a key factor to evaluate its stability and finally the long-term efficiency of the protection treatment.

Accurate modelling of unsteady flows in collapsible tubes.

PubMed

Marchandise, Emilie; Flaud, Patrice

2010-01-01

The context of this paper is the development of a general and efficient numerical haemodynamic tool to help clinicians and researchers in understanding of physiological flow phenomena. We propose an accurate one-dimensional Runge-Kutta discontinuous Galerkin (RK-DG) method coupled with lumped parameter models for the boundary conditions. The suggested model has already been successfully applied to haemodynamics in arteries and is now extended for the flow in collapsible tubes such as veins. The main difference with cardiovascular simulations is that the flow may become supercritical and elastic jumps may appear with the numerical consequence that scheme may not remain monotone if no limiting procedure is introduced. We show that our second-order RK-DG method equipped with an approximate Roe's Riemann solver and a slope-limiting procedure allows us to capture elastic jumps accurately. Moreover, this paper demonstrates that the complex physics associated with such flows is more accurately modelled than with traditional methods such as finite difference methods or finite volumes. We present various benchmark problems that show the flexibility and applicability of the numerical method. Our solutions are compared with analytical solutions when they are available and with solutions obtained using other numerical methods. Finally, to illustrate the clinical interest, we study the emptying process in a calf vein squeezed by contracting skeletal muscle in a normal and pathological subject. We compare our results with experimental simulations and discuss the sensitivity to parameters of our model.

Context-Aware Adaptive Hybrid Semantic Relatedness in Biomedical Science

NASA Astrophysics Data System (ADS)

Emadzadeh, Ehsan

Text mining of biomedical literature and clinical notes is a very active field of research in biomedical science. Semantic analysis is one of the core modules for different Natural Language Processing (NLP) solutions. Methods for calculating semantic relatedness of two concepts can be very useful in solutions solving different problems such as relationship extraction, ontology creation and question / answering [1--6]. Several techniques exist in calculating semantic relatedness of two concepts. These techniques utilize different knowledge sources and corpora. So far, researchers attempted to find the best hybrid method for each domain by combining semantic relatedness techniques and data sources manually. In this work, attempts were made to eliminate the needs for manually combining semantic relatedness methods targeting any new contexts or resources through proposing an automated method, which attempted to find the best combination of semantic relatedness techniques and resources to achieve the best semantic relatedness score in every context. This may help the research community find the best hybrid method for each context considering the available algorithms and resources.

Variational Methods in Design Optimization and Sensitivity Analysis for Two-Dimensional Euler Equations

NASA Technical Reports Server (NTRS)

Ibrahim, A. H.; Tiwari, S. N.; Smith, R. E.

1997-01-01

Variational methods (VM) sensitivity analysis employed to derive the costate (adjoint) equations, the transversality conditions, and the functional sensitivity derivatives. In the derivation of the sensitivity equations, the variational methods use the generalized calculus of variations, in which the variable boundary is considered as the design function. The converged solution of the state equations together with the converged solution of the costate equations are integrated along the domain boundary to uniquely determine the functional sensitivity derivatives with respect to the design function. The application of the variational methods to aerodynamic shape optimization problems is demonstrated for internal flow problems at supersonic Mach number range. The study shows, that while maintaining the accuracy of the functional sensitivity derivatives within the reasonable range for engineering prediction purposes, the variational methods show a substantial gain in computational efficiency, i.e., computer time and memory, when compared with the finite difference sensitivity analysis.

Conditioned taste aversion to ethanol in a social context: impact of age and sex.

PubMed

Morales, Melissa; Schatz, Kelcie C; Anderson, Rachel I; Spear, Linda P; Varlinskaya, Elena I

2014-03-15

Given that human adolescents place a high value on social interactions-particularly while consuming alcohol-the current study utilized a novel social drinking paradigm to examine rewarding and aversive properties of ethanol in non-water deprived rats that were housed and tested in groups of five same-sex littermates. On postnatal day P34 (adolescents) or P69 (adults), rats were habituated to the testing apparatus for 30 min. On the next day, animals were placed into the test apparatus and given 30 min access to a supersaccharin solution (3% sucrose; 0.125% saccharin), followed immediately by an intraperitoneal injection of ethanol (0, 0.25, 0.5, 1.0, 1.5 g/kg). Subsequent intake of the supersacharrin solution was assessed on three consecutive test days. Adolescent males were less sensitive to ethanol's aversive effects than adult males, with adolescent males maintaining an aversion on all three test days only at the 1.5 g/kg dose, whereas adults demonstrated aversions across test days to 1 and 1.5 g/kg. Adolescent females maintained aversions to 1 and 1.5 g/kg across days, whereas adult females continued to show an aversion to the 1.5 g/kg dose only. These opposite patterns of sensitivity that emerged among males and females at each age in the propensity to maintain an ethanol-induced taste aversion under social conditions may contribute to age- and sex-related differences in ethanol intake. Testing in social groups may be useful for future work when studying rodent models of adolescent alcohol use given the importance that human adolescents place on drinking in social settings. Copyright © 2014 Elsevier B.V. All rights reserved.

Linguistic Context Versus Semantic Competition in Word Recognition by Younger and Older Adults With Cochlear Implants.

PubMed

Amichetti, Nicole M; Atagi, Eriko; Kong, Ying-Yee; Wingfield, Arthur

The increasing numbers of older adults now receiving cochlear implants raises the question of how the novel signal produced by cochlear implants may interact with cognitive aging in the recognition of words heard spoken within a linguistic context. The objective of this study was to pit the facilitative effects of a constraining linguistic context against a potential age-sensitive negative effect of response competition on effectiveness of word recognition. Younger (n = 8; mean age = 22.5 years) and older (n = 8; mean age = 67.5 years) adult implant recipients heard 20 target words as the final words in sentences that manipulated the target word's probability of occurrence within the sentence context. Data from published norms were also used to measure response entropy, calculated as the total number of different responses and the probability distribution of the responses suggested by the sentence context. Sentence-final words were presented to participants using a word-onset gating paradigm, in which a target word was presented with increasing amounts of its onset duration in 50 msec increments until the word was correctly identified. Results showed that for both younger and older adult implant users, the amount of word-onset information needed for correct recognition of sentence-final words was inversely proportional to their likelihood of occurrence within the sentence context, with older adults gaining differential advantage from the contextual constraints offered by a sentence context. On the negative side, older adults' word recognition was differentially hampered by high response entropy, with this effect being driven primarily by the number of competing responses that might also fit the sentence context. Consistent with previous research with normal-hearing younger and older adults, the present results showed older adult implant users' recognition of spoken words to be highly sensitive to linguistic context. This sensitivity, however, also resulted in a greater degree of interference from other words that might also be activated by the context, with negative effects on ease of word recognition. These results are consistent with an age-related inhibition deficit extending to the domain of semantic constraints on word recognition.

Transfer of Solutions to Conditional Probability Problems: Effects of Example Problem Format, Solution Format, and Problem Context

ERIC Educational Resources Information Center

Chow, Alan F.; Van Haneghan, James P.

2016-01-01

This study reports the results of a study examining how easily students are able to transfer frequency solutions to conditional probability problems to novel situations. University students studied either a problem solved using the traditional Bayes formula format or using a natural frequency (tree diagram) format. In addition, the example problem…

Grounding statistical learning in context: The effects of learning and retrieval contexts on cross-situational word learning.

PubMed

Chen, Chi-Hsin; Yu, Chen

2017-06-01

Natural language environments usually provide structured contexts for learning. This study examined the effects of semantically themed contexts-in both learning and retrieval phases-on statistical word learning. Results from 2 experiments consistently showed that participants had higher performance in semantically themed learning contexts. In contrast, themed retrieval contexts did not affect performance. Our work suggests that word learners are sensitive to statistical regularities not just at the level of individual word-object co-occurrences but also at another level containing a whole network of associations among objects and their properties.

Three-dimensional solutions for the thermal buckling and sensitivity derivatives of temperature-sensitive multilayered angle-ply plates

NASA Technical Reports Server (NTRS)

Noor, A. K.; Burton, W. S.

1992-01-01

Analytic three-dimensional thermoelasticity solutions are presented for the thermal buckling of multilayered angle-ply composite plates with temperature-dependent thermoelastic properties. Both the critical temperatures and the sensitivity derivatives are computed. The sensitivity derivatives measure the sensitivity of the buckling response to variations in the different lamination and material parameters of the plate. The plates are assumed to have rectangular geometry and an antisymmetric lamination with respect to the middle plane. The temperature is assumed to be independent of the surface coordinates, but has an arbitrary symmetric variation through the thickness of the plate. The prebuckling deformations are accounted for. Numerical results are presented, for plates subjected to uniform temperature increase, showing the effects of temperature-dependent material properties on the prebuckling stresses, critical temperatures, and their sensitivity derivatives.

The scattering of Lyα radiation in the intergalactic medium: numerical methods and solutions

NASA Astrophysics Data System (ADS)

Higgins, Jonathan; Meiksin, Avery

2012-11-01

Two methods are developed for solving the steady-state spherically symmetric radiative transfer equation for resonance line radiation emitted by a point source in the intergalactic medium, in the context of the Wouthuysen-Field mechanism for coupling the hyperfine structure spin temperature of hydrogen to the gas temperature. One method is based on solving the ray and moment equations using finite differences. The second uses a Monte Carlo approach incorporating methods that greatly improve the accuracy compared with previous approaches in this context. Several applications are presented serving as test problems for both a static medium and an expanding medium, including inhomogeneities in the density and velocity fields. Solutions are obtained in the coherent scattering limit and for Doppler RII redistribution with and without recoils. We find generally that the radiation intensity is linear in the cosine of the azimuthal angle with respect to radius to high accuracy over a broad frequency region across the line centre for both linear and perturbed velocity fields, yielding the Eddington factors fν ≃ 1/3 and gν ≃ 3/5. The radiation field produced by a point source divides into three spatial regimes for a uniformly expanding homogeneous medium. The regimes are governed by the fraction of the distance r from the source in terms of the distance r* required for a photon to redshift from line centre to the frequency needed to escape from the expanding gas. For a standard cosmology, before the Universe was reionized r* takes on the universal value independent of redshift of 1.1 Mpc, depending only on the ratio of the baryon to dark matter density. At r/r* < 1, the radiation field is accurately described in the diffusion approximation, with the scattering rate declining with the distance from the source as r-7/3, except at r/r* ≪ 1 where frequency redistribution nearly doubles the mean intensity around line centre. At r/r* > 1, the diffusion approximation breaks down and the decline of the mean intensity near line centre and the scattering rate approach the geometric dilution scaling 1/r2. The mean intensity and scattering rate are found to be very sensitive to the gradient of the velocity field, growing exponentially with the amplitude of the perturbation as the limit of a vanishing velocity gradient is approached near the source. We expect the 21-cm signal from the epoch of reionization to thus be a sensitive probe of both the density and the peculiar velocity fields. The solutions for the mean intensity are made available in machine-readable format.

Validation of a Brazilian version of the moral sensitivity questionnaire.

PubMed

Dalla Nora, Carlise R; Zoboli, Elma Lcp; Vieira, Margarida M

2017-01-01

Moral sensitivity has been identified as a foundational component of ethical action. Diminished or absent moral sensitivity can result in deficient care. In this context, assessing moral sensitivity is imperative for designing interventions to facilitate ethical practice and ensure that nurses make appropriate decisions. The main purpose of this study was to validate a scale for examining the moral sensitivity of Brazilian nurses. A pre-existing scale, the Moral Sensitivity Questionnaire, which was developed by Lützén, was used after the deletion of three items. The reliability and validity of the scale were examined using Cronbach's alpha and factor analysis, respectively. Participants and research context: Overall, 316 nurses from Rio Grande do Sul, Brazil, participated in the study. Ethical considerations: This study was approved by the Ethics Committee of Research of the Nursing School of the University of São Paulo. The Moral Sensitivity Questionnaire contained 27 items that were distributed across four dimensions: interpersonal orientation, professional knowledge, moral conflict and moral meaning. The questionnaire accounted for 55.8% of the total variance, with Cronbach's alpha of 0.82. The mean score for moral sensitivity was 4.45 (out of 7). The results of this study were compared with studies from other countries to examine the structure and implications of the moral sensitivity of nurses in Brazil. The Moral Sensitivity Questionnaire is an appropriate tool for examining the moral sensitivity of Brazilian nurses.

German and Korean mothers' sensitivity and related parenting beliefs

PubMed Central

Ziehm, Jeanette; Trommsdorff, Gisela; Heikamp, Tobias; Park, Seong-Yeon

2013-01-01

This study contributes to a differentiated understanding of maternal sensitivity in cultural and situational context. We investigated differences and similarities in German and Korean mothers' maternal sensitivity. We interviewed 92 German and 100 Korean mothers of first graders about their preference for proactive (anticipating children's needs) or reactive sensitivity (responding to children's direct cues) in different scenarios. Related parenting beliefs were assessed by asking the mothers to explain the reasons why they would prefer specific parenting behaviors. Results revealed significant cultural differences in reactive vs. proactive sensitivity preferences. Overall, German mothers were more likely to indicate that a mother should respond reactively and less likely to report that a mother should act proactively than were Korean mothers. Korean mothers gave preference to both reactive and proactive sensitivity depending on the scenario. With regard to parenting beliefs, analyses revealed that German and Korean mothers who preferred reactive sensitivity mainly explained their choices as attempts to encourage children's development of independence. In contrast, Korean and German mothers with a preference for proactive sensitivity were more likely to report that mothers would assist their children due to their immaturity in dealing with emotional distress. Results are discussed in the framework of the different meanings and functions of maternal sensitivity for socialization in different cultural contexts. PMID:23986740

Antigenic Properties of the HIV Envelope on Virions in Solution

PubMed Central

Mengistu, Meron; Lewis, George K.; Lakowicz, Joseph R.

2014-01-01

The structural flexibility found in human immunodeficiency virus (HIV) envelope glycoproteins creates a complex relationship between antigenicity and sensitivity to antiviral antibodies. The study of this issue in the context of viral particles is particularly problematic as conventional virus capture approaches can perturb antigenicity profiles. Here, we employed a unique analytical system based on fluorescence correlation spectroscopy (FCS), which measures antibody-virion binding with all reactants continuously in solution. Panels of nine anti-envelope monoclonal antibodies (MAbs) and five virus types were used to connect antibody binding profiles with neutralizing activities. Anti-gp120 MAbs against the 2G12 or b12 epitope, which marks functional envelope structures, neutralized viruses expressing CCR5-tropic envelopes and exhibited efficient virion binding in solution. MAbs against CD4-induced (CD4i) epitopes considered hidden on functional envelope structures poorly bound these viruses and were not neutralizing. Anti-gp41 MAb 2F5 was neutralizing despite limited virion binding. Similar antigenicity patterns occurred on CXCR4-tropic viruses, except that anti-CD4i MAbs 17b and 19e were neutralizing despite little or no virion binding. Notably, anti-gp120 MAb PG9 and anti-gp41 MAb F240 bound to both CCR5-tropic and CXCR4-tropic viruses without exerting neutralizing activity. Differences in the virus production system altered the binding efficiencies of some antibodies but did not enhance antigenicity of aberrant gp120 structures. Of all viruses tested, only JRFL pseudoviruses showed a direct relationship between MAb binding efficiency and neutralizing potency. Collectively, these data indicate that the antigenic profiles of free HIV particles generally favor the exposure of functional over aberrant gp120 structures. However, the efficiency of virion-antibody interactions in solution inconsistently predicts neutralizing activity in vitro. PMID:24284318

Acoustic resonance scattering from a multilayered cylindrical shell with imperfect bonding.

PubMed

Rajabi, M; Hasheminejad, Seyyed M

2009-12-01

The method of wave function expansion is adopted to study the three dimensional scattering of a time-harmonic plane progressive sound field obliquely incident upon a multi-layered hollow cylinder with interlaminar bonding imperfection. For the generality of solution, each layer is assumed to be cylindrically orthotropic. An approximate laminate model in the context of the modal state equations with variable coefficients along with the classical T-matrix solution technique is set up for each layer to solve for the unknown modal scattering and transmission coefficients. A linear spring model is used to describe the interlaminar adhesive bonding whose effects are incorporated into the global transfer matrix by introduction of proper interfacial transfer matrices. Following the classic acoustic resonance scattering theory (RST), the scattered field and response to surface waves are determined by constructing the partial waves and obtaining the non-resonance (backgrounds) and resonance components. The solution is first used to investigate the effect of interlayer imperfection of an air-filled and water submerged bilaminate aluminium cylindrical shell on the resonances associated with various modes of wave propagation (i.e., symmetric/asymmetric Lamb waves, fluid-borne A-type waves, Rayleigh and Whispering Gallery waves) appearing in the backscattered spectrum, according to their polarization and state of stress. An illustrative numerical example is also given for a multi-layered (five-layered) cylindrical shell for which the stiffness of the adhesive interlayers is artificially varied. The sensitivity of resonance frequencies associated with higher mode numbers to the stiffness coefficients is demonstrated to be a good measure of the bonding strength. Limiting cases are considered and fair agreements with solutions available in the literature are established.

Optimal radiotherapy dose schedules under parametric uncertainty

NASA Astrophysics Data System (ADS)

Badri, Hamidreza; Watanabe, Yoichi; Leder, Kevin

2016-01-01

We consider the effects of parameter uncertainty on the optimal radiation schedule in the context of the linear-quadratic model. Our interest arises from the observation that if inter-patient variability in normal and tumor tissue radiosensitivity or sparing factor of the organs-at-risk (OAR) are not accounted for during radiation scheduling, the performance of the therapy may be strongly degraded or the OAR may receive a substantially larger dose than the allowable threshold. This paper proposes a stochastic radiation scheduling concept to incorporate inter-patient variability into the scheduling optimization problem. Our method is based on a probabilistic approach, where the model parameters are given by a set of random variables. Our probabilistic formulation ensures that our constraints are satisfied with a given probability, and that our objective function achieves a desired level with a stated probability. We used a variable transformation to reduce the resulting optimization problem to two dimensions. We showed that the optimal solution lies on the boundary of the feasible region and we implemented a branch and bound algorithm to find the global optimal solution. We demonstrated how the configuration of optimal schedules in the presence of uncertainty compares to optimal schedules in the absence of uncertainty (conventional schedule). We observed that in order to protect against the possibility of the model parameters falling into a region where the conventional schedule is no longer feasible, it is required to avoid extremal solutions, i.e. a single large dose or very large total dose delivered over a long period. Finally, we performed numerical experiments in the setting of head and neck tumors including several normal tissues to reveal the effect of parameter uncertainty on optimal schedules and to evaluate the sensitivity of the solutions to the choice of key model parameters.

Integrated Computational Solution for Predicting Skin Sensitization Potential of Molecules

PubMed Central

Desai, Aarti; Singh, Vivek K.; Jere, Abhay

2016-01-01

Introduction Skin sensitization forms a major toxicological endpoint for dermatology and cosmetic products. Recent ban on animal testing for cosmetics demands for alternative methods. We developed an integrated computational solution (SkinSense) that offers a robust solution and addresses the limitations of existing computational tools i.e. high false positive rate and/or limited coverage. Results The key components of our solution include: QSAR models selected from a combinatorial set, similarity information and literature-derived sub-structure patterns of known skin protein reactive groups. Its prediction performance on a challenge set of molecules showed accuracy = 75.32%, CCR = 74.36%, sensitivity = 70.00% and specificity = 78.72%, which is better than several existing tools including VEGA (accuracy = 45.00% and CCR = 54.17% with ‘High’ reliability scoring), DEREK (accuracy = 72.73% and CCR = 71.44%) and TOPKAT (accuracy = 60.00% and CCR = 61.67%). Although, TIMES-SS showed higher predictive power (accuracy = 90.00% and CCR = 92.86%), the coverage was very low (only 10 out of 77 molecules were predicted reliably). Conclusions Owing to improved prediction performance and coverage, our solution can serve as a useful expert system towards Integrated Approaches to Testing and Assessment for skin sensitization. It would be invaluable to cosmetic/ dermatology industry for pre-screening their molecules, and reducing time, cost and animal testing. PMID:27271321

Quaternary ammonium promoted ultra selective and sensitive fluorescence detection of fluoride ion in water and living cells.

PubMed

Li, Long; Ji, Yuzhuo; Tang, Xinjing

2014-10-21

Highly selective and sensitive fluorescent probes with a quaternary ammonium moiety have been rationally designed and developed for fast and sensitive fluorescence detection of fluoride ion (F(-) from NaF, not TBAF) in aqueous solution and living cells. With the sequestration effect of quaternary ammonium, the detection time was less than 2 min and the detection limit of fluoride ion was as low as 0.57 ppm that is among the lowest detection limits in aqueous solutions of many fluoride fluorescence probes in the literature.

When stress gets into your head: Socioeconomic risk, executive functions, and maternal sensitivity across childrearing contexts.

PubMed

Sturge-Apple, Melissa L; Jones, Hannah R; Suor, Jennifer H

2017-03-01

Socioeconomic adversity has been targeted as a key upstream mechanism with robust pathogenic effects on maternal caregiving. Although research has demonstrated the negative repercussions of socioeconomic difficulties, little research has documented potential mechanisms underlying this association. Toward increasing understanding, the present study examined how maternal working memory capacity and inhibitory control may mediate associations between socioeconomic risk and change in maternal sensitivity across free-play and discipline caregiving contexts. This study used a longitudinal design, and utilized a socioeconomically diverse sample of 185 mothers and their 3.5-year-old toddlers. Multi-informants and methods were used to assess constructs. Findings revealed that maternal EF mediated associations between socioeconomic risk and parenting sensitivity with specific effects for working memory and baseline sensitivity and inhibitory control and change in sensitivity as childrearing demands increased. Results are interpreted within emerging conceptual frameworks regarding the role of parental neurocognitive functioning and caregiving. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Child Negative Emotionality and Caregiver Sensitivity across Context: Links with Children's Kindergarten Behaviour Problems

ERIC Educational Resources Information Center

Hartz, Karyn; Williford, Amanda

2015-01-01

Behavioural adjustment is critical for children's school readiness. This study used data from a nationally representative sample of children from the Early Childhood Longitudinal Study-Birth Cohort. We examined the effects of interactions between children's negative emotionality, maternal sensitivity and preschool teacher sensitivity on children's…

Culture in Context: An Interdisciplinary Travel Study Course.

ERIC Educational Resources Information Center

Berger, Karen A.; O'Neill, Geraldine P.

2002-01-01

Describes an interdisciplinary travel study course designed to teach cultural appreciation and sensitivity in context. Readings and instruction focus on cultural issues that affect business and marketing practices, using France and the French as the subjects of the study. (Author/VWL)

Fabrication of Amperometric Glucose Sensor Using Glucose Oxidase-Cellulose Nanofiber Aqueous Solution.

PubMed

Yasuzawa, Mikito; Omura, Yuya; Hiura, Kentaro; Li, Jiang; Fuchiwaki, Yusuke; Tanaka, Masato

2015-01-01

Cellulose nanofiber aqueous solution, which remained virtually transparent for more than one week, was prepared by using the clear upper layer of diluted cellulose nanofiber solution produced by wet jet milling. Glucose oxidase (GOx) was easily dissolved in this solution and GOx-immobilized electrode was easily fabricated by simple repetitious drops of GOx-cellulose solution on the surface of a platinum-iridium electrode. Glucose sensor properties of the obtained electrodes were examined in phosphate buffer solution of pH 7.4 at 40°C. The obtained electrode provided a glucose sensor response with significantly high response speed and good linear relationship between glucose concentration and response current. After an initial decrease of response sensitivity for a few days, relatively constant sensitivity was obtained for about 20 days. Nevertheless, the influence of electroactive compounds such as ascorbic acid, uric acid and acetoaminophen were not negletable.

Mobile Context Provider for Social Networking

NASA Astrophysics Data System (ADS)

Santos, André C.; Cardoso, João M. P.; Ferreira, Diogo R.; Diniz, Pedro C.

The ability to infer user context based on a mobile device together with a set of external sensors opens up the way to new context-aware services and applications. In this paper, we describe a mobile context provider that makes use of sensors available in a smartphone as well as sensors externally connected via bluetooth. We describe the system architecture from sensor data acquisition to feature extraction, context inference and the publication of context information to well-known social networking services such as Twitter and Hi5. In the current prototype, context inference is based on decision trees, but the middleware allows the integration of other inference engines. Experimental results suggest that the proposed solution is a promising approach to provide user context to both local and network-level services.

High sensitivity pyrogen testing in water and dialysis solutions.

PubMed

Daneshian, Mardas; Wendel, Albrecht; Hartung, Thomas; von Aulock, Sonja

2008-07-20

The dialysis patient is confronted with hundreds of litres of dialysis solution per week, which pass the natural protective barriers of the body and are brought into contact with the tissue directly in the case of peritoneal dialysis or indirectly in the case of renal dialysis (hemodialysis). The components can be tested for living specimens or dead pyrogenic (fever-inducing) contaminations. The former is usually detected by cultivation and the latter by the endotoxin-specific Limulus Amoebocyte Lysate Assay (LAL). However, the LAL assay does not reflect the response of the human immune system to the wide variety of possible pyrogenic contaminations in dialysis fluids. Furthermore, the test is limited in its sensitivity to detect extremely low concentrations of pyrogens, which in their sum result in chronic pathologies in dialysis patients. The In vitro Pyrogen Test (IPT) employs human whole blood to detect the spectrum of pyrogens to which humans respond by measuring the release of the endogenous fever mediator interleukin-1beta. Spike recovery checks exclude interference. The test has been validated in an international study for pyrogen detection in injectable solutions. In this study we adapted the IPT to the testing of dialysis solutions. Preincubation of 50 ml spiked samples with albumin-coated microspheres enhanced the sensitivity of the assay to detect contaminations down to 0.1 pg/ml LPS or 0.001 EU/ml in water or saline and allowed pyrogen detection in dialysis concentrates or final working solutions. This method offers high sensitivity detection of human-relevant pyrogens in dialysis solutions and components.

Students' Images of Problem Contexts when Solving Applied Problems

ERIC Educational Resources Information Center

Moore, Kevin C.; Carlson, Marilyn P.

2012-01-01

This article reports findings from an investigation of precalculus students' approaches to solving novel problems. We characterize the images that students constructed during their solution attempts and describe the degree to which they were successful in imagining how the quantities in a problem's context change together. Our analyses revealed…

Dynamic behaviour of a planar micro-beam loaded by a fluid-gap: Analytical and numerical approach in a high frequency range, benchmark solutions

NASA Astrophysics Data System (ADS)

Novak, A.; Honzik, P.; Bruneau, M.

2017-08-01

Miniaturized vibrating MEMS devices, active (receivers or emitters) or passive devices, and their use for either new applications (hearing, meta-materials, consumer devices,…) or metrological purposes under non-standard conditions, are involved today in several acoustic domains. More in-depth characterisation than the classical ones available until now are needed. In this context, the paper presents analytical and numerical approaches for describing the behaviour of three kinds of planar micro-beams of rectangular shape (suspended rigid or clamped elastic planar beam) loaded by a backing cavity or a fluid-gap, surrounded by very thin slits, and excited by an incident acoustic field. The analytical approach accounts for the coupling between the vibrating structure and the acoustic field in the backing cavity, the thermal and viscous diffusion processes in the boundary layers in the slits and the cavity, the modal behaviour for the vibrating structure, and the non-uniformity of the acoustic field in the backing cavity which is modelled in using an integral formulation with a suitable Green's function. Benchmark solutions are proposed in terms of beam motion (from which the sensitivity, input impedance, and pressure transfer function can be calculated). A numerical implementation (FEM) is handled against which the analytical results are tested.

Analytical Modeling Tool for Design of Hydrocarbon Sensitive Optical Fibers

PubMed Central

Vahdati, Nader; Lawand, Lydia

2017-01-01

Pipelines are the main transportation means for oil and gas products across large distances. Due to the severe conditions they operate in, they are regularly inspected using conventional Pipeline Inspection Gages (PIGs) for corrosion damage. The motivation for researching a real-time distributed monitoring solution arose to mitigate costs and provide a proactive indication of potential failures. Fiber optic sensors with polymer claddings provide a means of detecting contact with hydrocarbons. By coating the fibers with a layer of metal similar in composition to that of the parent pipeline, corrosion of this coating may be detected when the polymer cladding underneath is exposed to the surrounding hydrocarbons contained within the pipeline. A Refractive Index (RI) change occurs in the polymer cladding causing a loss in intensity of a traveling light pulse due to a reduction in the fiber’s modal capacity. Intensity losses may be detected using Optical Time Domain Reflectometry (OTDR) while pinpointing the spatial location of the contact via time delay calculations of the back-scattered pulses. This work presents a theoretical model for the above sensing solution to provide a design tool for the fiber optic cable in the context of hydrocarbon sensing following corrosion of an external metal coating. Results are verified against the experimental data published in the literature. PMID:28956847

Analytical Modeling Tool for Design of Hydrocarbon Sensitive Optical Fibers.

PubMed

Al Handawi, Khalil; Vahdati, Nader; Shiryayev, Oleg; Lawand, Lydia

2017-09-28

Pipelines are the main transportation means for oil and gas products across large distances. Due to the severe conditions they operate in, they are regularly inspected using conventional Pipeline Inspection Gages (PIGs) for corrosion damage. The motivation for researching a real-time distributed monitoring solution arose to mitigate costs and provide a proactive indication of potential failures. Fiber optic sensors with polymer claddings provide a means of detecting contact with hydrocarbons. By coating the fibers with a layer of metal similar in composition to that of the parent pipeline, corrosion of this coating may be detected when the polymer cladding underneath is exposed to the surrounding hydrocarbons contained within the pipeline. A Refractive Index (RI) change occurs in the polymer cladding causing a loss in intensity of a traveling light pulse due to a reduction in the fiber's modal capacity. Intensity losses may be detected using Optical Time Domain Reflectometry (OTDR) while pinpointing the spatial location of the contact via time delay calculations of the back-scattered pulses. This work presents a theoretical model for the above sensing solution to provide a design tool for the fiber optic cable in the context of hydrocarbon sensing following corrosion of an external metal coating. Results are verified against the experimental data published in the literature.

Developmental continuity in reward-related enhancement of cognitive control.

PubMed

Strang, Nicole M; Pollak, Seth D

2014-10-01

Adolescents engage in more risky behavior than children or adults. The most prominent hypothesis for this phenomenon is that brain systems governing reward sensitivity and brain systems governing self-regulation mature at different rates. Those systems governing reward sensitivity mature in advance of those governing self-control. This hypothesis has substantial empirical support, however, the evidence supporting this theory has been exclusively derived from contexts where self-control systems are required to regulate reward sensitivity in order to promote adaptive behavior. In adults, reward promotes a shift to a proactive control strategy and better cognitive control performance. It is unclear whether children and adolescents will respond to reward in the same way. Using fMRI methodology, we explored whether children and adolescents would demonstrate a shift to proactive control in the context of reward. We tested 22 children, 20 adolescents, and 23 adults. In contrast to our hypothesis, children, adolescents, and adults all demonstrated a shift to proactive cognitive control in the context of reward. In light of the results, current neurobiological theories of adolescent behavior need to be refined to reflect that in certain contexts there is continuity in the manner reward and cognitive control systems interact across development. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Measuring the Degree of Sensitization (DOS) Using an Electrochemical Technique

NASA Astrophysics Data System (ADS)

Abuzriba, Mokhtar B.; Musa, Salem M.

Sensitization can be simply defined as the susceptibility of an alloy, specifically austenitic stainless steel, to corrosion at grain boundaries. A detailed study on types 304 stainless steel has been carried out to correlate the degree of sensitization measured by electrochemical potentiokinetic reactivation test (EPR) with the susceptibility to intergranular corrosion. In this study four different heat treatments were given to alloys, i.e., solution annealed (SA) at 1020 °C for 1 h, then quenched in water; also then heat-treated in air at 620 °C for 15, 30, and 60 min. The electrolyte for the EPR tests was 1.0 N H2SO4 solution containing 0.01 M KSCN. Potentiodynamic curves from passive to active regions in deaerated solution at room temperature were obtained at a scan rate of 1.67 mV/s (6 V/h), after the passivation at 200 mV versus (SCE) for 2 min then the polarization was conducted. The criterion used to distinguish between sensitized and non-sensitized specimens is the activation charge Pa, the peak current density, Ph, in the active state, and Flade potential Ef at which the active curve breaks upward. The results indicated that the longer the sensitization time the higher the activation charge (Pa), and the higher the peak current density in the active state (Ph). The results indicated that, the EPR is more sensitive than the chemical method for measuring the degree of sensitization.

The Contexts of mathematics tasks and the context of the classroom: Are we including all students?

NASA Astrophysics Data System (ADS)

Sullivan, Peter; Zevenbergen, Robyn; Mousley, Judith

2003-09-01

Mathematics teachers are encouraged to use realistic contexts in order to make mathematics more meaningful and accessible for all students. However, the focus group research reported in this article shows that decisions on the suitability of contexts are complex and multidimensional. Similarly, the way the task contexts are presented, and the way the tasks are incorporated into classroom routines have potential to alienate some groups of students. We suggest that teachers and researchers should be sensitive to difficulties that students might experience as a result of both the task and classroom contexts, and take specific steps to avoid or overcome the difficulties.

Highly sensitive glucose sensors based on enzyme-modified whole-graphene solution-gated transistors

NASA Astrophysics Data System (ADS)

Zhang, Meng; Liao, Caizhi; Mak, Chun Hin; You, Peng; Mak, Chee Leung; Yan, Feng

2015-02-01

Noninvasive glucose detections are convenient techniques for the diagnosis of diabetes mellitus, which require high performance glucose sensors. However, conventional electrochemical glucose sensors are not sensitive enough for these applications. Here, highly sensitive glucose sensors are successfully realized based on whole-graphene solution-gated transistors with the graphene gate electrodes modified with an enzyme glucose oxidase. The sensitivity of the devices is dramatically improved by co-modifying the graphene gates with Pt nanoparticles due to the enhanced electrocatalytic activity of the electrodes. The sensing mechanism is attributed to the reaction of H2O2 generated by the oxidation of glucose near the gate. The optimized glucose sensors show the detection limits down to 0.5 μM and good selectivity, which are sensitive enough for non-invasive glucose detections in body fluids. The devices show the transconductances two orders of magnitude higher than that of a conventional silicon field effect transistor, which is the main reason for their high sensitivity. Moreover, the devices can be conveniently fabricated with low cost. Therefore, the whole-graphene solution-gated transistors are a high-performance sensing platform for not only glucose detections but also many other types of biosensors that may find practical applications in the near future.

Highly sensitive glucose sensors based on enzyme-modified whole-graphene solution-gated transistors

PubMed Central

Zhang, Meng; Liao, Caizhi; Mak, Chun Hin; You, Peng; Mak, Chee Leung; Yan, Feng

2015-01-01

Noninvasive glucose detections are convenient techniques for the diagnosis of diabetes mellitus, which require high performance glucose sensors. However, conventional electrochemical glucose sensors are not sensitive enough for these applications. Here, highly sensitive glucose sensors are successfully realized based on whole-graphene solution-gated transistors with the graphene gate electrodes modified with an enzyme glucose oxidase. The sensitivity of the devices is dramatically improved by co-modifying the graphene gates with Pt nanoparticles due to the enhanced electrocatalytic activity of the electrodes. The sensing mechanism is attributed to the reaction of H2O2 generated by the oxidation of glucose near the gate. The optimized glucose sensors show the detection limits down to 0.5 μM and good selectivity, which are sensitive enough for non-invasive glucose detections in body fluids. The devices show the transconductances two orders of magnitude higher than that of a conventional silicon field effect transistor, which is the main reason for their high sensitivity. Moreover, the devices can be conveniently fabricated with low cost. Therefore, the whole-graphene solution-gated transistors are a high-performance sensing platform for not only glucose detections but also many other types of biosensors that may find practical applications in the near future. PMID:25655666

Ethical sensitivity in professional practice: concept analysis.

PubMed

Weaver, Kathryn; Morse, Janice; Mitcham, Carl

2008-06-01

This paper is a report of a concept analysis of ethical sensitivity. Ethical sensitivity enables nurses and other professionals to respond morally to the suffering and vulnerability of those receiving professional care and services. Because of its significance to nursing and other professional practices, ethical sensitivity deserves more focused analysis. A criteria-based method oriented toward pragmatic utility guided the analysis of 200 papers and books from the fields of nursing, medicine, psychology, dentistry, clinical ethics, theology, education, law, accounting or business, journalism, philosophy, political and social sciences and women's studies. This literature spanned 1970 to 2006 and was sorted by discipline and concept dimensions and examined for concept structure and use across various contexts. The analysis was completed in September 2007. Ethical sensitivity in professional practice develops in contexts of uncertainty, client suffering and vulnerability, and through relationships characterized by receptivity, responsiveness and courage on the part of professionals. Essential attributes of ethical sensitivity are identified as moral perception, affectivity and dividing loyalties. Outcomes include integrity preserving decision-making, comfort and well-being, learning and professional transcendence. Our findings promote ethical sensitivity as a type of practical wisdom that pursues client comfort and professional satisfaction with care delivery. The analysis and resulting model offers an inclusive view of ethical sensitivity that addresses some of the limitations with prior conceptualizations.

Semiautomated Workflow for Clinically Streamlined Glioma Parametric Response Mapping

PubMed Central

Keith, Lauren; Ross, Brian D.; Galbán, Craig J.; Luker, Gary D.; Galbán, Stefanie; Zhao, Binsheng; Guo, Xiaotao; Chenevert, Thomas L.; Hoff, Benjamin A.

2017-01-01

Management of glioblastoma multiforme remains a challenging problem despite recent advances in targeted therapies. Timely assessment of therapeutic agents is hindered by the lack of standard quantitative imaging protocols for determining targeted response. Clinical response assessment for brain tumors is determined by volumetric changes assessed at 10 weeks post-treatment initiation. Further, current clinical criteria fail to use advanced quantitative imaging approaches, such as diffusion and perfusion magnetic resonance imaging. Development of the parametric response mapping (PRM) applied to diffusion-weighted magnetic resonance imaging has provided a sensitive and early biomarker of successful cytotoxic therapy in brain tumors while maintaining a spatial context within the tumor. Although PRM provides an earlier readout than volumetry and sometimes greater sensitivity compared with traditional whole-tumor diffusion statistics, it is not routinely used for patient management; an automated and standardized software for performing the analysis and for the generation of a clinical report document is required for this. We present a semiautomated and seamless workflow for image coregistration, segmentation, and PRM classification of glioblastoma multiforme diffusion-weighted magnetic resonance imaging scans. The software solution can be integrated using local hardware or performed remotely in the cloud while providing connectivity to existing picture archive and communication systems. This is an important step toward implementing PRM analysis of solid tumors in routine clinical practice. PMID:28286871

Myocardial T2* Mapping at Ultrahigh Field: Physics and Frontier Applications

NASA Astrophysics Data System (ADS)

Huelnhagen, Till; Paul, Katharina; Ku, Min-Chi; Serradas Duarte, Teresa; Niendorf, Thoralf

2017-06-01

Cardiovascular magnetic resonance imaging (CMR) has become an indispensable clinical tool for the assessment of morphology, function and structure of the heart muscle. By exploiting quantification of the effective transverse relaxation time (T2*) CMR also affords myocardial tissue characterization and probing of cardiac physiology, both being in the focus of ongoing research. These developments are fueled by the move to ultrahigh magnetic field strengths, which permits enhanced sensitivity and spatial resolution that help to overcome limitations of current clinical MR systems with the goal to contribute to a better understanding of myocardial (patho)physiology in vivo. In this context, the aim of this report is to introduce myocardial T2* mapping at ultrahigh magnetic fields as a promising technique to non-invasively assess myocardial (patho)physiology. For this purpose the basic principles of T2* assessment, the biophysical mechanisms determining T2* and (pre)clinical applications of myocardial T2* mapping are presented. Technological challenges and solutions for T2* sensitized CMR at ultrahigh magnetic field strengths are discussed followed by a review of acquisition techniques and post processing approaches. Preliminary results derived from myocardial T2* mapping in healthy subjects and cardiac patients at 7.0 Tesla are presented. A concluding section discusses remaining questions and challenges and provides an outlook on future developments and potential clinical applications.

Unsteady adjoint for large eddy simulation of a coupled turbine stator-rotor system

NASA Astrophysics Data System (ADS)

Talnikar, Chaitanya; Wang, Qiqi; Laskowski, Gregory

2016-11-01

Unsteady fluid flow simulations like large eddy simulation are crucial in capturing key physics in turbomachinery applications like separation and wake formation in flow over a turbine vane with a downstream blade. To determine how sensitive the design objectives of the coupled system are to control parameters, an unsteady adjoint is needed. It enables the computation of the gradient of an objective with respect to a large number of inputs in a computationally efficient manner. In this paper we present unsteady adjoint solutions for a coupled turbine stator-rotor system. As the transonic fluid flows over the stator vane, the boundary layer transitions to turbulence. The turbulent wake then impinges on the rotor blades, causing early separation. This coupled system exhibits chaotic dynamics which causes conventional adjoint solutions to diverge exponentially, resulting in the corruption of the sensitivities obtained from the adjoint solutions for long-time simulations. In this presentation, adjoint solutions for aerothermal objectives are obtained through a localized adjoint viscosity injection method which aims to stabilize the adjoint solution and maintain accurate sensitivities. Preliminary results obtained from the supercomputer Mira will be shown in the presentation.

Ion sensitivity of large-area epitaxial graphene film on SiC substrate

NASA Astrophysics Data System (ADS)

Mitsuno, Takanori; Taniguchi, Yoshiaki; Ohno, Yasuhide; Nagase, Masao

2017-11-01

We investigated the intrinsic ion sensitivity of graphene field-effect transistors (FETs) fabricated by a resist-free stencil mask lithography process from a large-scale graphene film epitaxially grown on a SiC substrate. A pH-adjusted phosphate-buffered solution was used for the measurement to eliminate the interference of other ions on the graphene FET's ion sensitivity. The charge neutrality point shifted negligibly with changing pH for the pH-adjusted phosphate-buffered solution, whereas for the mixed buffer solution, it shifted toward the negative gate voltage owing to the decrease in the concentration of phthalate ions. This phenomenon is contrary to that observed in previous reports. Overall, our results indicate that the graphene film is intrinsically insensitive to ions except for those with functional groups that interact with the graphene surface.

Situational Context Affects Definiteness Preferences: Accommodation of Presuppositions

PubMed Central

Clifton, Charles

2013-01-01

Four experiments used self-paced reading and eyetracking to demonstrate that readers are, under some conditions, sensitive to the presuppositions of definite vs. indefinite DPs (determiner phrases). Reading was faster when the context stereotypically provided a single possible referent for a definite DP or multiple possible referents for an indefinite DP than when context and DP definiteness were mismatched. This finding goes beyond previous evidence that definite DPs are processed more rapidly than indefinite DPs when there is a unique or familiar referent in the context, showing that readers are sensitive to the semantics and pragmatics of (in)definiteness. However, the finding was obtained only when readers had to perform a simple arithmetic task between reading a sentence and seeing a question about it. The intervening task may have encouraged them to process the sentence more deeply in order to form a representation that would persist while doing the arithmetic. The methodological implications of this observation are discussed. PMID:22732029

Nature's crucible: Manufacturing optical nonlinearities for high resolution, high sensitivity encoding in the compound eye of the fly, Musca domestica

NASA Technical Reports Server (NTRS)

Wilcox, Mike

1993-01-01

The number of pixels per unit area sampling an image determines Nyquist resolution. Therefore, the highest pixel density is the goal. Unfortunately, as reduction in pixel size approaches the wavelength of light, sensitivity is lost and noise increases. Animals face the same problems and have achieved novel solutions. Emulating these solutions offers potentially unlimited sensitivity with detector size approaching the diffraction limit. Once an image is 'captured', cellular preprocessing of information allows extraction of high resolution information from the scene. Computer simulation of this system promises hyperacuity for machine vision.

Verification of S&D Solutions for Network Communications and Devices

NASA Astrophysics Data System (ADS)

Rudolph, Carsten; Compagna, Luca; Carbone, Roberto; Muñoz, Antonio; Repp, Jürgen

This chapter describes the tool-supported verification of S&D Solutions on the level of network communications and devices. First, the general goals and challenges of verification in the context of AmI systems are highlighted and the role of verification and validation within the SERENITY processes is explained.Then, SERENITY extensions to the SH VErification tool are explained using small examples. Finally, the applicability of existing verification tools is discussed in the context of the AVISPA toolset. The two different tools show that for the security analysis of network and devices S&D Patterns relevant complementary approachesexist and can be used.

A new method of content based medical image retrieval and its applications to CT imaging sign retrieval.

PubMed

Ma, Ling; Liu, Xiabi; Gao, Yan; Zhao, Yanfeng; Zhao, Xinming; Zhou, Chunwu

2017-02-01

This paper proposes a new method of content based medical image retrieval through considering fused, context-sensitive similarity. Firstly, we fuse the semantic and visual similarities between the query image and each image in the database as their pairwise similarities. Then, we construct a weighted graph whose nodes represent the images and edges measure their pairwise similarities. By using the shortest path algorithm over the weighted graph, we obtain a new similarity measure, context-sensitive similarity measure, between the query image and each database image to complete the retrieval process. Actually, we use the fused pairwise similarity to narrow down the semantic gap for obtaining a more accurate pairwise similarity measure, and spread it on the intrinsic data manifold to achieve the context-sensitive similarity for a better retrieval performance. The proposed method has been evaluated on the retrieval of the Common CT Imaging Signs of Lung Diseases (CISLs) and achieved not only better retrieval results but also the satisfactory computation efficiency. Copyright © 2017 Elsevier Inc. All rights reserved.

EXAMINING THE DIMENSIONALITY OF COLQUITT'S ORGANIZATIONAL JUSTICE SCALE IN A PUBLIC HEALTH SECTOR CONTEXT.

PubMed

Enoksen, Elisabeth

2015-06-01

In 2001, Colquitt developed an Organizational Justice Scale that intended to measure procedural, distributive, interpersonal, and informational justice. The dimensionality of the scale has been tested in subsequent studies with diverging results. Given the fact that contextual differences may account for more variation across research sites than individual differences, the deviating research findings may be due to context. This study examined the dimensionality of Colquitt's Organizational Justice Scale in a new context: the public health sector. The procedural and informational justice dimensions were highly correlated, but confirmatory factor analysis showed that a four-factor solution provided a better fit than a three-factor solution. All fit indices for the four-factor model were consistent with a good model. There was, however, evidence of a potential omitted factor, procedural-voice justice, which has also been found in a previous examination of the measure in the public sector.

The SERENITY Runtime Framework

NASA Astrophysics Data System (ADS)

Crespo, Beatriz Gallego-Nicasio; Piñuela, Ana; Soria-Rodriguez, Pedro; Serrano, Daniel; Maña, Antonio

The SERENITY Runtime Framework (SRF) provides support for applications at runtime, by managing S&D Solutions and monitoring the systems’ context. The main functionality of the SRF, amongst others, is to provide S&D Solutions, by means of Executable Components, in response to applications security requirements. Runtime environment is defined in SRF through the S&D Library and Context Manager components. S&D Library is a local S&D Artefact repository, and stores S&D Classes, S&D Patterns and S&D Implementations. The Context Manager component is in charge of storing and management of the information used by the SRF to select the most appropriate S&D Pattern for a given scenario. The management of the execution of the Executable Component, as running realizations of the S&D Patterns, including instantiation, de-activation and control, as well as providing communication and monitoring mechanisms, besides the recovery and reconfiguration aspects, complete the list of tasks performed by the SRF.

Superposition: New Solutions from Known Solutions

ERIC Educational Resources Information Center

Roberts, Charles E.

2003-01-01

This note contains material to be presented to students in a first course in differential equations immediately after they have completed studying first-order differential equations and their applications. The purpose of presenting this material is four-fold: to review definitions studied previously; to provide a historical context which cites the…

Tellurium: A new sensitive test

USGS Publications Warehouse

Lakin, H.W.; Thompson, C.E.

1963-01-01

A new, extremely sensitive method for the quantitative determination of tellurium is based on the induced precipitation of elemental gold from a 6N HCl solution containing gold chloride, cupric chloride, and hypophosphorous acid; the amount of gold reduced is proportional to the amount of tellurium present. As little as 1 nanogram (1 ?? 70-9 g) of tellurium gives a measurable reaction with 1 mg of gold in 50 ml of solution.

Context awareness and sensitivity in SEA implementation

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

Hilding-Rydevik, Tuija; Bjarnadottir, Holmfridur

2007-10-15

The Impact Assessment research community repeatedly asserts that the implementation of Strategic Environmental Assessment (SEA) should take the issue of context into consideration. The primary aim of this paper then is to attempt to give substance to the concept of 'context' in relation to the implementation of SEA. The second aim is to discuss the relevance of context consciousness and sensitivity in relation to one of the main aims given to SEA implementation i.e. to contribute to the 'integration' of environmental perspectives in planning processes. Context must be defined in relation to a certain question. In this paper the questionmore » in focus is the assumption that SEA implementation will contribute to integration of environmental issues in planning processes. Research results relating to the use of environmental tools, like for example SEA, and experiences of integration efforts, strongly indicate that the use of a single tool like SEA is not enough to achieve this integration. The current 'context free' normative and procedural assumptions concerning the aim of SEA implementation and 'best practice' in term of SEA can be criticised on the same grounds as normative and procedural planning theories, as being context free. The assumptions behind the current formulations of the aim and best practice of SEA need to be revisited. A firm empirical and theoretical knowledge and discussion is needed, especially in relation to the issue of context and integration. This paper provides a starting point in this direction.« less

Results with OECD recommended positive control sensitizers in the maximization, Buehler and local lymph node assays.

PubMed

Basketter, D A; Selbie, E; Scholes, E W; Lees, D; Kimber, I; Botham, P A

1993-01-01

The guinea pig maximization test and the Buehler occluded patch test are used widely to identify the sensitization potential of new chemicals. This information enables toxicologists and/or regulatory authorities to determine whether a chemical should be classified formally as a skin sensitizer. Both to improve and to harmonize these assessments internationally, the OECD has recommended recently that moderate rather than strong contact sensitizers are used as positive control substances. The purpose is to ensure an adequate level of sensitivity in sensitization assays performed at specific testing establishments. Results from two laboratories reported here show that the minimum acceptable standard laid down by the OECD can be achieved and indeed commonly exceeded by a substantial margin. Furthermore, results with these positive controls in a new method, the local lymph node assay, also appear to satisfy similar criteria, suggesting results from this assay, including negative data, should be acceptable for classification purposes. However, a review of the way in which results with new chemicals will be interpreted for regulatory purposes, in the context of positive control data, reveals that considerable inadequacies still exist. It is recommended that ultimately, sensitization data can only be interpreted meaningfully (i.e. to protect humans from sensitization hazards) by considering the potency of the contact allergen in the context of the sensitivity of the assay performed at the particular testing institution.

Beyond Deficit: Graduate Student Research-Writing Pedagogies

ERIC Educational Resources Information Center

Badenhorst, Cecile; Moloney, Cecilia; Rosales, Janna; Dyer, Jennifer; Ru, Lina

2015-01-01

Graduate writing is receiving increasing attention, particularly in contexts of diverse student bodies and widening access to universities. In many of these contexts, writing is seen as "a problem" in need of fixing. Often, the problem and the solution are perceived as being solely located in notions of deficit in individuals and not in…

A Context-Aware Solution in Mobile Language Learning

ERIC Educational Resources Information Center

Fatahipour, Majid; Ghaseminajm, Mahnaz

2014-01-01

Despite obvious benefits, some challenges exist in the way of sustainable utilization of mobile phone technology for language learning tasks. This paper shows how these challenges can be better addressed in the light of recent advancements in mobile phone technology, like context aware mobile learning, informed with a sound pedagogical basis for…

Effects of Context on Students' Molecular-Level Ideas

ERIC Educational Resources Information Center

Teichert, Melonie A.; Tien, Lydia T.; Anthony, Seth; Rickey, Dawn

2008-01-01

In the studies reported here, we investigate the effects of context on students' molecular-level ideas regarding aqueous solutions. During one-on-one interviews, 19 general chemistry students recruited from a two-year community college and a research university in the United States were asked to describe their molecular-level ideas about various…

Students' Difficulties with Applying a Familiar Formula in an Unfamiliar Context

ERIC Educational Resources Information Center

Hoch, Maureen; Dreyfus, Tommy

2005-01-01

This paper discusses problems many tenth grade students have when asked to apply a familiar formula in an unfamiliar context: specifically factoring a compound expression. Some of their attempts at solution are presented and discussed in terms of structure sense. (Contains 1 table.) [For complete proceedings, see ED496848.

Context Orientated Teaching in Praxis

ERIC Educational Resources Information Center

Nikos, Klaoudatos; Stavros, Papastavridis

2004-01-01

In this paper, we describe the skeleton of two teaching units, based on a Model for teaching mathematics, Context Orientated Teaching (COT). The first teaching unit concerns the proof of a mathematical proposition, while the second one concerns the solution of an open problem. Both are taught in the 10th grade, under the specific conditions of the…

Rich context information for just-in-time adaptive intervention promoting physical activity.

PubMed

Cruciani, F; Nugent, C; Cleland, I; McCullagh, P

2017-07-01

Sedentary lifestyle and inadequate levels of physical activity represent two serious health risk factors. Nevertheless, within developed countries, 60% of people aged over 60 are deemed to be sedentary. Consequently, interest in behavior change to promote physical activity is increasing. In particular, the role of emerging mobile apps to facilitate behavior change has shown promising results. Smart technologies can help in providing rich context information including an objective assessment of the level of physical activity and information on the emotional and physiological state of the person. Collectively, this can be used to develop innovative persuasive solutions for adaptive behavior change. Such solutions offer potential in reducing levels of sedentary behavior. This work presents a study exploring new ways of employing smart technologies to facilitate behavior change. It is achieved by means of (i) developing a knowledge base on sedentary behaviors and recommended physical activity guidelines, and (ii) a context model able to combine information on physical activity, location, and a user's diary to develop a context-aware virtual coach with the ability to select the most appropriate behavior change strategy on a case by case basis.

Medicine shortages in Fiji: A qualitative exploration of stakeholders' views.

PubMed

Walker, Josephine; Chaar, Betty B; Vera, Numa; Pillai, Alvish S; Lim, Jessy S; Bero, Lisa; Moles, Rebekah J

2017-01-01

Medicine access is a human right; yet, concerningly, there are international instances of shortages. Quantitative data has allowed WHO to propose global solutions; however, individualised understanding of specific regions is still required to work towards national solutions. Fiji has an established issue with medication supply and the aim of this study was to use qualitative methods to gain a fuller understanding of this context. Semi-structured interviews were used to gain the perspective of key stakeholders involved in the Fijian medicine supply chain in regards to causes, impacts and possible solutions of medicine shortages. Thematic analysis was used to analyse the interview data. In total, 48 stakeholders participated and the information was synthesised into three main themes, causes, impacts and solutions and the sub-themes including; political, system and patient causes, adverse health effects on patients, professional dissatisfaction, monetary loss and loss of faith in the health system, workarounds, operation improvements, government intervention and education and training. The situation in Fiji is not dissimilar to other instances of shortages around the world and hence international solutions like that proposed by WHO are feasible; however, they must be modified to be uniquely Fijian to work in this context.

Medicine shortages in Fiji: A qualitative exploration of stakeholders’ views

PubMed Central

Chaar, Betty B.; Vera, Numa; Pillai, Alvish S.; Lim, Jessy S.; Bero, Lisa; Moles, Rebekah J.

2017-01-01

Objectives Medicine access is a human right; yet, concerningly, there are international instances of shortages. Quantitative data has allowed WHO to propose global solutions; however, individualised understanding of specific regions is still required to work towards national solutions. Fiji has an established issue with medication supply and the aim of this study was to use qualitative methods to gain a fuller understanding of this context. Methods Semi-structured interviews were used to gain the perspective of key stakeholders involved in the Fijian medicine supply chain in regards to causes, impacts and possible solutions of medicine shortages. Thematic analysis was used to analyse the interview data. Results In total, 48 stakeholders participated and the information was synthesised into three main themes, causes, impacts and solutions and the sub-themes including; political, system and patient causes, adverse health effects on patients, professional dissatisfaction, monetary loss and loss of faith in the health system, workarounds, operation improvements, government intervention and education and training. Conclusions The situation in Fiji is not dissimilar to other instances of shortages around the world and hence international solutions like that proposed by WHO are feasible; however, they must be modified to be uniquely Fijian to work in this context. PMID:28582409

Context Aware Middleware Architectures: Survey and Challenges

PubMed Central

Li, Xin; Eckert, Martina; Martinez, José-Fernán; Rubio, Gregorio

2015-01-01

Context aware applications, which can adapt their behaviors to changing environments, are attracting more and more attention. To simplify the complexity of developing applications, context aware middleware, which introduces context awareness into the traditional middleware, is highlighted to provide a homogeneous interface involving generic context management solutions. This paper provides a survey of state-of-the-art context aware middleware architectures proposed during the period from 2009 through 2015. First, a preliminary background, such as the principles of context, context awareness, context modelling, and context reasoning, is provided for a comprehensive understanding of context aware middleware. On this basis, an overview of eleven carefully selected middleware architectures is presented and their main features explained. Then, thorough comparisons and analysis of the presented middleware architectures are performed based on technical parameters including architectural style, context abstraction, context reasoning, scalability, fault tolerance, interoperability, service discovery, storage, security & privacy, context awareness level, and cloud-based big data analytics. The analysis shows that there is actually no context aware middleware architecture that complies with all requirements. Finally, challenges are pointed out as open issues for future work. PMID:26307988

Comparison of wheat and rye flour solutions for skin prick testing: a multi-centre study (Stad 1).

PubMed

van Kampen, V; Merget, R; Rabstein, S; Sander, I; Bruening, T; Broding, H C; Keller, C; Muesken, H; Overlack, A; Schultze-Werninghaus, G; Walusiak, J; Raulf-Heimsoth, M

2009-12-01

Skin prick testing (SPT) is the basic method for diagnosing IgE-mediated allergies. However, skin reactivity is related to the quality of allergen extracts, which are often poorly defined for occupational allergens. To compare wheat and rye flour SPT solutions from different producers. Standardized SPTs were performed in seven allergy centres with wheat and rye flour solutions from four producers in 125 symptomatic bakers. Optimal cut-off levels for weal sizes were assessed with the Youden Index. Comparisons between SPT results of different solutions were made with flour-specific IgE (sIgE) as the gold standard. Sensitivities, specificities, positive and negative predictive values, and test efficiencies were calculated and compared with McNemar and chi(2)-tests. The influence of the choice of the gold standard (sIgE or challenge) test was examined for 95 subjects. Additionally, SPT solutions were analysed for protein and antigen content. The optimal cut-off level for all SPT solutions was a weal size of >or=1.5 mm. While differences between wheat and rye flours were small, differences between producers were important. Variability of sensitivities (0.31-0.96), negative predictive values (0.42-0.91), and test efficiencies (0.54-0.90) were higher than variations of specificities (0.74-1.00) and positive predictive values (0.88-1.00). Similar results were obtained when using challenge test results as the gold standard. Variability could be explained by the different antigen contents of the SPT solutions. There is a wide variability of SPT solutions for wheat and rye flour from different producers, mainly with respect to sensitivities, negative predictive values, and test efficiencies. Improvement and standardization of SPT solutions used for the diagnosis of baker's asthma are highly recommended.

Nonschematic drawing recognition: a new approach based on attributed graph grammar with flexible embedding

NASA Astrophysics Data System (ADS)

Lee, Kyu J.; Kunii, T. L.; Noma, T.

1993-01-01

In this paper, we propose a syntactic pattern recognition method for non-schematic drawings, based on a new attributed graph grammar with flexible embedding. In our graph grammar, the embedding rule permits the nodes of a guest graph to be arbitrarily connected with the nodes of a host graph. The ambiguity caused by this flexible embedding is controlled with the evaluation of synthesized attributes and the check of context sensitivity. To integrate parsing with the synthesized attribute evaluation and the context sensitivity check, we also develop a bottom up parsing algorithm.

Improving Terminology Mapping in Clinical Text with Context-Sensitive Spelling Correction.

PubMed

Dziadek, Juliusz; Henriksson, Aron; Duneld, Martin

2017-01-01

The mapping of unstructured clinical text to an ontology facilitates meaningful secondary use of health records but is non-trivial due to lexical variation and the abundance of misspellings in hurriedly produced notes. Here, we apply several spelling correction methods to Swedish medical text and evaluate their impact on SNOMED CT mapping; first in a controlled evaluation using medical literature text with induced errors, followed by a partial evaluation on clinical notes. It is shown that the best-performing method is context-sensitive, taking into account trigram frequencies and utilizing a corpus-based dictionary.

A psycho-historical research program for the integrative science of art.

PubMed

Bullot, Nicolas J; Reber, Rolf

2013-04-01

Critics of the target article objected to our account of art appreciators' sensitivity to art-historical contexts and functions, the relations among the modes of artistic appreciation, and the weaknesses of aesthetic science. To rebut these objections and justify our program, we argue that the current neglect of sensitivity to art-historical contexts persists as a result of a pervasive aesthetic–artistic confound; we further specify our claim that basic exposure and the design stance are necessary conditions of artistic understanding; and we explain why many experimental studies do not belong to a psycho-historical science of art.

Conflict resolution styles: a comparison of assisted living and nursing home facilities.

PubMed

Small, Jeff A; Montoro-Rodriguez, Julian

2006-01-01

In this exploratory study, the authors investigated how interpersonal conflict is resolved in assisted living and nursing home facilities. In particular, the authors examined whether conflict resolution styles differed between type of facility and between residents and staff in each type of facility. Four focus groups were conducted--two with residents and two with staff from each type of facility. The focus groups centered on discussing the occurrence of conflict and how each participant handled it. Discourse analysis was employed to identify participants' use of three styles of conflict resolution: controlling, solution-oriented, and non-confrontational. The results indicate that staff in each care context showed a preference for the solution-oriented approach. Residents in each setting reported equal use of the non-confrontational and solution-oriented styles. The findings suggest that preferred conflict resolution styles may vary more as a function of the role of each communicator than the context of the care setting.

Morphology Development in Solution-Processed Functional Organic Blend Films: An In Situ Viewpoint.

PubMed

Richter, Lee J; DeLongchamp, Dean M; Amassian, Aram

2017-05-10

Solution-processed organic films are a facile route to high-speed, low cost, large-area deposition of electrically functional components (transistors, solar cells, emitters, etc.) that can enable a diversity of emerging technologies, from Industry 4.0, to the Internet of things, to point-of-use heath care and elder care. The extreme sensitivity of the functional performance of organic films to structure and the general nonequilibrium nature of solution drying result in extreme processing-performance correlations. In this Review, we highlight insights into the fundamentals of solution-based film deposition afforded by recent state-of-the-art in situ measurements of functional film drying. Emphasis is placed on multimodal studies that combine surface-sensitive X-ray scattering (GIWAXS or GISAXS) with optical characterization to clearly define the evolution of solute structure (aggregation, crystallinity, and morphology) with film thickness.

Diminishing the side effect of mitomycin C by using pH-sensitive liposomes: in vitro characterization and in vivo pharmacokinetics

PubMed Central

Fang, Yi-Ping; Hu, Pei-Yu; Huang, Yaw-Bin

2018-01-01

Introduction Mitomycin C is an anticancer antibiotic agent that has the potential for broad-spectrum use against several cancers, including mammary cancers. Because its half-life is 17 min after a 30 mg intravenous bolus administration, the suitability of mitomycin C for wide use in the clinical setting is limited. Based on tumor pathophysiology, pH-sensitive liposomes could provide better tumor-targeted effects. The aim of this study was to investigate the possibility of diminishing the side effect of mitomycin C by using pH-sensitive liposomes. Materials and methods pH-sensitive liposomes was employed to deliver mitomycin C and evaluate the characterization, release behaviors, cytotoxicity, in vivo pharmacokinetics and biochemical assay. Results The results demonstrated that mitomycin C-loaded pH-sensitive liposomes had a particle diameter of 144.5±2.8 nm and an entrapment efficiency of 66.5%. The in vitro release study showed that the pH-sensitive liposome release percentages at pH 7.4 and pH 5.5 were approximately 47% and 93%, respectively. The cell viability of MCF-7 cells showed that both the solution and liposome group exhibited a concentration-dependent effect on cell viability. The MCF-7 cell uptake of pH-sensitive liposomes with a folate modification was higher which was indicated by an increased fluorescence intensity compared to that without a folate modification. The area under the concentration–time curve of mitomycin C-loaded pH-sensitive liposomes (18.82±0.51 µg·h/L) was significantly higher than that of the mitomycin C solution group (10.07±0.31 µg·h/L). The mean residence times of the mitomycin C-loaded and mitomycin C solution groups were 1.53±0.16 and 0.05 h, respectively. In addition, there was no significant difference in terms of Vss (p>0.05). Moreover, the half-life of pH-sensitive liposomes and the mitomycin C solution was 1.35±0.15 and 1.60±0.04 h, respectively. In terms of safety, mitomycin C-loaded pH-sensitive liposomes did not affect the platelet count and the levels of blood urea nitrogen and aspartate aminotransferase. Conclusion The positive results of pH-sensitive liposomes demonstrated maintained the cytotoxicity and decrease the side effect. PMID:29391780

Diminishing the side effect of mitomycin C by using pH-sensitive liposomes: in vitro characterization and in vivo pharmacokinetics.

PubMed

Fang, Yi-Ping; Hu, Pei-Yu; Huang, Yaw-Bin

2018-01-01

Mitomycin C is an anticancer antibiotic agent that has the potential for broad-spectrum use against several cancers, including mammary cancers. Because its half-life is 17 min after a 30 mg intravenous bolus administration, the suitability of mitomycin C for wide use in the clinical setting is limited. Based on tumor pathophysiology, pH-sensitive liposomes could provide better tumor-targeted effects. The aim of this study was to investigate the possibility of diminishing the side effect of mitomycin C by using pH-sensitive liposomes. pH-sensitive liposomes was employed to deliver mitomycin C and evaluate the characterization, release behaviors, cytotoxicity, in vivo pharmacokinetics and biochemical assay. The results demonstrated that mitomycin C-loaded pH-sensitive liposomes had a particle diameter of 144.5±2.8 nm and an entrapment efficiency of 66.5%. The in vitro release study showed that the pH-sensitive liposome release percentages at pH 7.4 and pH 5.5 were approximately 47% and 93%, respectively. The cell viability of MCF-7 cells showed that both the solution and liposome group exhibited a concentration-dependent effect on cell viability. The MCF-7 cell uptake of pH-sensitive liposomes with a folate modification was higher which was indicated by an increased fluorescence intensity compared to that without a folate modification. The area under the concentration-time curve of mitomycin C-loaded pH-sensitive liposomes (18.82±0.51 µg·h/L) was significantly higher than that of the mitomycin C solution group (10.07±0.31 µg·h/L). The mean residence times of the mitomycin C-loaded and mitomycin C solution groups were 1.53±0.16 and 0.05 h, respectively. In addition, there was no significant difference in terms of V ss ( p >0.05). Moreover, the half-life of pH-sensitive liposomes and the mitomycin C solution was 1.35±0.15 and 1.60±0.04 h, respectively. In terms of safety, mitomycin C-loaded pH-sensitive liposomes did not affect the platelet count and the levels of blood urea nitrogen and aspartate aminotransferase. The positive results of pH-sensitive liposomes demonstrated maintained the cytotoxicity and decrease the side effect.

Process and apparatus for producing ultrafine explosive particles

DOEpatents

McGowan, Michael J.

1992-10-20

A method and an improved eductor apparatus for producing ultrafine explosive particles is disclosed. The explosive particles, which when incorporated into a binder system, have the ability to propagate in thin sheets, and have very low impact sensitivity and very high propagation sensitivity. A stream of a solution of the explosive dissolved in a solvent is thoroughly mixed with a stream of an inert nonsolvent by obtaining nonlaminar flow of the streams by applying pressure against the flow of the nonsolvent stream, to thereby diverge the stream as it contacts the explosive solution, and violently agitating the combined stream to rapidly precipitate the explosive particles from the solution in the form of generally spheroidal, ultrafine particles. The two streams are injected coaxially through continuous, concentric orifices of a nozzle into a mixing chamber. Preferably, the nonsolvent stream is injected centrally of the explosive solution stream. The explosive solution stream is injected downstream of and surrounds the nonsolvent solution stream for a substantial distance prior to being ejected into the mixing chamber.

A dictionary server for supplying context sensitive medical knowledge.

PubMed

Ruan, W; Bürkle, T; Dudeck, J

2000-01-01

The Giessen Data Dictionary Server (GDDS), developed at Giessen University Hospital, integrates clinical systems with on-line, context sensitive medical knowledge to help with making medical decisions. By "context" we mean the clinical information that is being presented at the moment the information need is occurring. The dictionary server makes use of a semantic network supported by a medical data dictionary to link terms from clinical applications to their proper information sources. It has been designed to analyze the network structure itself instead of knowing the layout of the semantic net in advance. This enables us to map appropriate information sources to various clinical applications, such as nursing documentation, drug prescription and cancer follow up systems. This paper describes the function of the dictionary server and shows how the knowledge stored in the semantic network is used in the dictionary service.

Context sensitivity and ambiguity in component-based systems design

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

Bespalko, S.J.; Sindt, A.

1997-10-01

Designers of components-based, real-time systems need to guarantee to correctness of soft-ware and its output. Complexity of a system, and thus the propensity for error, is best characterized by the number of states a component can encounter. In many cases, large numbers of states arise where the processing is highly dependent on context. In these cases, states are often missed, leading to errors. The following are proposals for compactly specifying system states which allow the factoring of complex components into a control module and a semantic processing module. Further, the need for methods that allow for the explicit representation ofmore » ambiguity and uncertainty in the design of components is discussed. Presented herein are examples of real-world problems which are highly context-sensitive or are inherently ambiguous.« less

Cultivating nature-based solutions: The governance of communal urban gardens in the European Union.

PubMed

van der Jagt, Alexander P N; Szaraz, Luca R; Delshammar, Tim; Cvejić, Rozalija; Santos, Artur; Goodness, Julie; Buijs, Arjen

2017-11-01

In many countries in the European Union (EU), the popularity of communal urban gardening (CUG) on allotments and community gardens is on the rise. Given the role of this practice in increasing urban resilience, most notably social resilience, municipalities in the Global North are promoting CUG as a nature-based solution (NbS). However, the mechanisms by which institutional actors can best support and facilitate CUG are understudied, which could create a gap between aspiration and reality. The aim of this study is therefore to identify what governance arrangements contribute to CUG delivering social resilience. Through the EU GREEN SURGE project, we studied six CUG initiatives from five EU-countries, representing different planning regimes and traditions. We selected cases taking a locally unique or innovative approach to dealing with urban challenges. A variety of actors associated with each of the cases were interviewed to achieve as complete a picture as possible regarding important governance arrangements. A cross-case comparison revealed a range of success factors, varying from clearly formulated objectives and regulations, municipal support, financial resources and social capital through to the availability of local food champions and facilitators engaging in community building. Municipalities can support CUG initiatives by moving beyond a rigid focus on top-down control, while involved citizens can increase the impact of CUG by pursuing political, in addition to hands-on, activities. We conclude that CUG has clear potential to act as a nature-based solution if managed with sensitivity to local dynamics and context. Copyright © 2017 Elsevier Inc. All rights reserved.

Optical micro resonance based sensor schemes for detection and identification of nano particles and biological agents in situ

NASA Astrophysics Data System (ADS)

Saetchnikov, Vladimir A.; Tcherniavskaia, Elina A.; Schweiger, Gustav; Ostendorf, Andreas

2010-05-01

A novel emerging technique for the label-free analysis of nano particles including biomolecules using optical micro cavity resonance is being developed. Various schemes based on a mechanically fixed microspheres as well as microspheres melted by laser on the tip of a standard single mode fiber have been investigated to make further development for microbial application. Water solutions of ethanol, HCl, glucose, vitamin C and biotin have been used to test refractive index changes by monitoring the magnitude of the whispering gallery modes spectral shift. Particular efforts were made for effective fixing of the micro spheres in the water flow, an optimal geometry for micro resonance observation and material of microsphere the most appropriate for microbial application. Optical resonance in free micro spheres from PMMA fixed in micro channels produced by photolithography has been observed under the laser power of less then 1 microwatt. Resonance shifts of C reactive protein water solutions as well as albumin solutions in pure water and with HCl modelling blood have been investigated. Introducing controlled amount of glass gel nano particles into sensor microsphere surrounding were accompanied by both correlative resonance shift (400 nm in diameter) and total reconstruct of resonance spectra (57 nm in diameter). Developed schemes have been demonstrated to be a promising technology platform for sensitive, lab-on-chip type sensor of diagnostic tools for different biological molecules, e.g. proteins, oligonucleotides, oligosaccharides, lipids, small molecules, viral particles, cells as well as in different experimental contexts e.g. proteomics, genomics, drug discovery, and membrane studies.

Reversal of apomorphine locomotor sensitization by a single post-conditioning trial treatment with a low autoreceptor dose of apomorphine: a memory re-consolidation approach.

PubMed

Carrera, Marinete Pinheiro; Carey, Robert J; Dias, Flávia Regina Cruz; de Matos, Liana Wermelinger

2011-07-01

Sensitization is a common feature of psychostimulants and sensitization effects are generally considered to be linked to the addictive properties of these drugs. We used a conventional paired/unpaired Pavlovian protocol to induce a context specific sensitization to the locomotor stimulant effect of a high dose of apomorphine (2.0mg/kg). Two days following a 5 session sensitization induction phase, a brief 5min non-drug test for conditioning was conducted. Only the paired groups exhibited locomotor stimulant conditioned response effects. Immediately following this brief test for conditioning, the paired and the unpaired groups received injections of 0.05mg/kg apomorphine, 2.0mg/kg apomorphine or vehicle designed to differentially impact memory re-consolidation of the conditioning. Two days later, all groups received a sensitization challenge test with 2.0mg/kg apomorphine. The 2.0mg/kg apomorphine post-trial treatment potentiated sensitization while the 0.05mg/kg eliminated sensitization. These effects were only observed in the paired groups. The activation of dopaminergic systems by the high dose of apomorphine strengthened the drug/environment association whereas the inhibition of dopamine activity by the low auto-receptor dose eliminated this association. The results point to the importance of conditioning to context specific sensitization and targeting memory re-consolidation of conditioning as a paradigm to modify sensitization. Copyright © 2011 Elsevier Inc. All rights reserved.

Hippocampal volume and sensitivity to maternal aggressive behavior: a prospective study of adolescent depressive symptoms.

PubMed

Whittle, Sarah; Yap, Marie B H; Sheeber, Lisa; Dudgeon, Paul; Yücel, Murat; Pantelis, Christos; Simmons, Julian G; Allen, Nicholas B

2011-02-01

It has been suggested that biological factors confer increased sensitivity to environmental influences on depressive symptoms during adolescence, a crucial time for the onset of depressive disorders. Given the critical role of the hippocampus in sensitivity to stress and processing of contextual aspects of the environment, investigation of its role in determining sensitivity to environmental context seems warranted. This study prospectively examined hippocampal volume as a measure of sensitivity to the influence of aggressive maternal behavior on change in depressive symptoms from early to midadolescence. The interaction between aggressive maternal behavior and hippocampal volume was found to predict change in depressive symptoms. Significant sex differences also emerged, whereby only for girls were larger bilateral hippocampal volumes more sensitive to the effects of maternal aggressive behavior, particularly with respect to experiencing the protective effects of low levels of maternal aggressiveness. These findings help elucidate the complex relationships between brain structure, environmental factors such as maternal parenting style, and sensitivity to (i.e., risk for, and protection from) the emergence of depression during this life stage. Given that family context risk factors are modifiable, our findings suggest the potential utility of targeted parenting interventions for the prevention and treatment of adolescent depressive disorder.

Drosophila Bitter Taste(s)

PubMed Central

French, Alice; Ali Agha, Moutaz; Mitra, Aniruddha; Yanagawa, Aya; Sellier, Marie-Jeanne; Marion-Poll, Frédéric

2015-01-01

Most animals possess taste receptors neurons detecting potentially noxious compounds. In humans, the ligands which activate these neurons define a sensory space called “bitter”. By extension, this term has been used in animals and insects to define molecules which induce aversive responses. In this review, based on our observations carried out in Drosophila, we examine how bitter compounds are detected and if bitter-sensitive neurons respond only to molecules bitter to humans. Like most animals, flies detect bitter chemicals through a specific population of taste neurons, distinct from those responding to sugars or to other modalities. Activating bitter-sensitive taste neurons induces aversive reactions and inhibits feeding. Bitter molecules also contribute to the suppression of sugar-neuron responses and can lead to a complete inhibition of the responses to sugar at the periphery. Since some bitter molecules activate bitter-sensitive neurons and some inhibit sugar detection, bitter molecules are represented by two sensory spaces which are only partially congruent. In addition to molecules which impact feeding, we recently discovered that the activation of bitter-sensitive neurons also induces grooming. Bitter-sensitive neurons of the wings and of the legs can sense chemicals from the gram negative bacteria, Escherichia coli, thus adding another biological function to these receptors. Bitter-sensitive neurons of the proboscis also respond to the inhibitory pheromone, 7-tricosene. Activating these neurons by bitter molecules in the context of sexual encounter inhibits courting and sexual reproduction, while activating these neurons with 7-tricosene in a feeding context will inhibit feeding. The picture that emerges from these observations is that the taste system is composed of detectors which monitor different “categories” of ligands, which facilitate or inhibit behaviors depending on the context (feeding, sexual reproduction, hygienic behavior), thus considerably extending the initial definition of “bitter” tasting. PMID:26635553

Context-dependent efficacy of a counter-conditioning strategy with atypical neuroleptic drugs in mice previously sensitized to cocaine.

PubMed

Oliveira-Lima, A J; Marinho, Eav; Santos-Baldaia, R; Hollais, A W; Baldaia, M A; Talhati, F; Ribeiro, L T; Wuo-Silva, R; Berro, L F; Frussa-Filho, R

2017-02-06

We have previously demonstrated that treatment with ziprasidone and aripiprazole selectively inhibit the development of behavioral sensitization to cocaine in mice. We now investigate their effects on a counter-conditioning strategy in mice and the importance of the treatment environment for this phenomenon. Evaluate the context-specificity of ziprasidone and aripiprazole on conditioned locomotion to cocaine and cocaine-induced hyperlocomotion and behavioral sensitization in a counter-conditioning strategy in mice. Animals were sensitized with saline or cocaine injections in the open-field apparatus in a 15-day intermittent treatment and subsequently treated with vehicle, 5mg/kg ziprasidone or 0.1mg/kg aripiprazole paired to the open-field or the home-cage for 4 alternate days. Mice were then challenged with saline and cocaine in the open-field apparatus on subsequent days. While treatment with ziprasidone decreased spontaneous locomotion and conditioned locomotion alike, treatment with aripiprazole specifically attenuated the expression of conditioned hyperlocomotion to cocaine. Ziprasidone and aripiprazole had no effects on cocaine-induced conditioned hyperlocomotion observed during saline challenge after drug withdrawal. Treatment with either ziprasidone or aripiprazole when previously given in the cocaine-paired environment attenuated the subsequent expression of behavioral sensitization to cocaine. Animals treated with aripiprazole in the open-field, but not in the home-cage, showed a blunted response to cocaine when receiving a cocaine challenge for the first time. Both neuroleptic drugs showed a context-dependent effectiveness in attenuating long-term expression of cocaine-induced behavioral sensitization when administered in the cocaine-associated environment, with aripiprazole also showing effectiveness in blocking the expression of acute cocaine effects. Copyright © 2016. Published by Elsevier Inc.

[A core deficit in Parkinson disease?].

PubMed

Benítez-Burraco, A; Herrera, E; Cuetos, F

2016-05-01

Parkinson disease is a neurodegenerative condition involving motor, cognitive, and linguistic deficits. It is important to know why all these different deficits co-occur in the affected people. This paper aims to clarify whether these comorbid deficits result from the selective impairment of a computational primitive, namely, a context-sensitive computational ability according to Chomsky's Hierarchy (a well-established research tool in comparative neuroscience). A total of 15 medicated subjects with Parkinson disease and 15 controls were selected. They were matched in age and education. A battery of tasks was designed to test 3 different domains (motor capacities, cognition, and language) and 2 different computational abilities (context-free and context-sensitive operations). Significant differences between groups were observed only regarding the linguistic task involving context-sensitive computations (correferences). The observed deficits in our patients with Parkinson disease cannot be explained in terms of the selective impairment of one only unspecific, low-level computational process. At the same time, differences between patients and controls are expected to be greater if the former are not medicated. Moreover, we should pursue in the search of (this kind of) computational primitives than can be selectively impaired in people with Parkinson disease, because they may help to achieve an earlier diagnosis of this condition. Copyright © 2014 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

On integrability of the Yang-Baxter {sigma}-model

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

Klimcik, Ctirad

2009-04-15

We prove that the recently introduced Yang-Baxter {sigma}-model can be considered as an integrable deformation of the principal chiral model. We find also an explicit one-to-one map transforming every solution of the principal chiral model into a solution of the deformed model. With the help of this map, the standard procedure of the dressing of the principal chiral solutions can be directly transferred into the deformed Yang-Baxter context.

Reducing microwave absorption with fast frequency modulation.

PubMed

Qin, Juehang; Hubler, A

2017-05-01

We study the response of a two-level quantum system to a chirp signal, using both numerical and analytical methods. The numerical method is based on numerical solutions of the Schrödinger solution of the two-level system, while the analytical method is based on an approximate solution of the same equations. We find that when two-level systems are perturbed by a chirp signal, the peak population of the initially unpopulated state exhibits a high sensitivity to frequency modulation rate. We also find that the aforementioned sensitivity depends on the strength of the forcing, and weaker forcings result in a higher sensitivity, where the frequency modulation rate required to produce the same reduction in peak population would be lower. We discuss potential applications of this result in the field of microwave power transmission, as it shows applying fast frequency modulation to transmitted microwaves used for power transmission could decrease unintended absorption of microwaves by organic tissue.

Magnetic Field Effects on Triplet-Triplet Annihilation in Solutions: Modulation of Visible/NIR Luminescence.

PubMed

Mani, Tomoyasu; Vinogradov, Sergei A

2013-08-06

Photon upconversion based on sensitized triplet-triplet annihilation (TTA) presents interest for such areas as photovoltaics and imaging. Usually energy upconversion is observed as p -type delayed fluorescence from molecules whose triplet states are populated via energy transfer from a suitable triplet donor, followed by TTA. Magnetic field effects (MFE) on delayed fluorescence in molecular crystals are well known; however, there exist only a few examples of MFE on TTA in solutions, and all of them are limited to UV-emitting materials. Here we present MFE on TTA-mediated visible and near infrared (NIR) emission, sensitized by far-red absorbing metalloporphyrins in solutions at room temperature. In addition to visible delayed fluorescence from annihilator, we also observed NIR emission from the sensitizer, occurring as a result of triplet-triplet energy transfer back from annihilator, termed "delayed phosphorescence". This emission also exhibits MFE, but opposite in sign to the annihilator fluorescence.

Children Use Vowels to Help Them Spell Consonants

ERIC Educational Resources Information Center

Hayes, Heather; Treiman, Rebecca; Kessler, Brett

2006-01-01

English spelling is highly inconsistent in terms of simple sound-to-spelling correspondences but is more consistent when context is taken into account. For example, the choice between "ch" and "tch" is determined by the preceding vowel ("coach," "roach" vs. "catch," "hatch"). We investigated children's sensitivity to vowel context when spelling…

Maternal Sensitivity and Child Responsiveness: Associations with Social Context, Maternal Characteristics, and Child Characteristics in a Multivariate Analysis

ERIC Educational Resources Information Center

Bornstein, Marc H.; Hendricks, Charlene; Haynes, O. Maurice; Painter, Kathleen M.

2007-01-01

This study examined unique associations of multiple distal context variables (family socioeconomic status [SES], maternal employment, and paternal parenting) and proximal maternal (personality, intelligence, and knowledge; behavior, self-perceptions, and attributions) and child (age, gender, representation, language, and sociability)…

Adaptation by Design: A Context-Sensitive, Dialogic Approach to Interventions

ERIC Educational Resources Information Center

Kirshner, Ben; Polman, Joseph L.

2013-01-01

Applied researchers, whether working with the framework of design-based research or intervention science, face a similar implementation challenge: practitioners who enact their programs typically do so in varied, context-specific ways. Although this variability is often seen as a problem for those who privilege fidelity and standardization, we…

Social Work Preparation to Compete in Today's Scientific Marketplace

ERIC Educational Resources Information Center

Nurius, Paula S.

2017-01-01

As the scientific marketplace rapidly evolves, we must keep revisiting strategic preparation of our doctoral students and early career scholars to be successful innovators in these contexts. As an inherently integrative, change-oriented, community-engaged, and context-sensitive discipline, social work has enormous potential as a value-added…

Situational Context Affects Definiteness Preferences: Accommodation of Presuppositions

ERIC Educational Resources Information Center

Clifton, Charles, Jr.

2013-01-01

In 4 experiments, we used self-paced reading and eye tracking to demonstrate that readers are, under some conditions, sensitive to the presuppositions of definite versus indefinite determiner phrases (DPs). Reading was faster when the context stereotypically provided a single possible referent for a definite DP or multiple possible referents for…

Sentence Context Affects the Brain Response to Masked Words

ERIC Educational Resources Information Center

Coulson, Seana; Brang, David

2010-01-01

Historically, language researchers have assumed that lexical, or word-level processing is fast and automatic, while slower, more controlled post-lexical processes are sensitive to contextual information from higher levels of linguistic analysis. Here we demonstrate the impact of sentence context on the processing of words not available for…

Nuclear Data Covariances in the Indian Context – Progress, Challenges, Excitement and Perspectives

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

Ganesan, S., E-mail: gane-san555@gmail.com

We present a brief overview of progress, challenges, excitement and perspectives in developing nuclear data covariances in the Indian context in relation to target accuracies and sensitivity studies that are of great importance to Bhabha's 3-stage nuclear programme for energy and non-energy applications.

Leading Multiethnic Schools: A New Understanding of Muslim Youth Identity

ERIC Educational Resources Information Center

Shah, Saeeda

2006-01-01

In the context of emigration, immigration, international mobility and globalization, the management contexts of education sites are undergoing deep and sensitive changes making challenging demands on educational leaders. Multiethnic/multicultural schools are emerging as a long-term phenomenon in countries such as Britain against the backdrop of…

Unexpected photoproduct generated via the acetone-sensitized photolysis of 5-bromo-2'-deoxyuridine in a water/isopropanol solution: experimental and computational studies.

PubMed

Polska, Katarzyna; Zielonka, Justyna; Chomicz, Lidia; Czerwicka, Małgorzata; Stepnowski, Piotr; Guzow, Katarzyna; Wiczk, Wiesław; Smużyńska, Maria; Kasprzykowski, Franciszek; Żylicz-Stachula, Agnieszka; Skowron, Piotr; Rak, Janusz

2010-12-23

The acetone-sensitized photolysis of 5-bromo-2'-deoxyuridine (5-BrdU) in a water/isopropanol solution with 300 nm photons leads to the formation of 2'-deoxyuridine (dU) and a comparable amount of another photoproduct that has not been reported in the literature so far. The negative and positive mass spectra recorded for this species indicate that they originate from the molecular mass of 286 Da, which corresponds to an adduct of 2'-deoxyuridine and 2-propanol. Quantum chemical calculations carried out at the DFT and TDDFT levels reveal both the structure and the UV spectrum of that adduct. The latter computational characteristic matches well the experimental UV spectrum of the new photoproduct. Our findings indicate that the acetone-sensitized photolysis of 5-BrdU is more complicated than has hitherto been assumed. Nevertheless, since electron transfer is one of the pathways responsible for 5-BrdU decay, acetone-sensitized photolysis of the halogen derivatives of nucleobases could be a convenient tool for studying their radiosensitivity in aqueous solutions.

Sensitivity of Optimal Solutions to Control Problems for Second Order Evolution Subdifferential Inclusions.

PubMed

Bartosz, Krzysztof; Denkowski, Zdzisław; Kalita, Piotr

In this paper the sensitivity of optimal solutions to control problems described by second order evolution subdifferential inclusions under perturbations of state relations and of cost functionals is investigated. First we establish a new existence result for a class of such inclusions. Then, based on the theory of sequential [Formula: see text]-convergence we recall the abstract scheme concerning convergence of minimal values and minimizers. The abstract scheme works provided we can establish two properties: the Kuratowski convergence of solution sets for the state relations and some complementary [Formula: see text]-convergence of the cost functionals. Then these two properties are implemented in the considered case.

A fluorescence study of liposomes entrapped in sol-gel materials

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

Yamanaka, S.A.; Singh, S.; Sasaki, D.Y.

1997-12-31

Liposomes of phosphatidylcholine lipids were successfully entrapped in silicates using the sol-gel method with complete retention of the molecular aggregates over long periods in aqueous solution. Fluorescent studies of the small unilamellar vesicles of 5% pyrene labeled lipid PSIDA with DSPC remobilized in the gel found significant lipid reorganization upon aging in aqueous solutions. Monitoring of pyrene excimer (470 nm) to monomer (375 nm) ratios in the bilayer reveals that the silicate matrix tends to disperse PSIDA lipid aggregates from that observed in free solution. On an interesting note, the liposomes in the gel at pH 7.5. The PSIDA/DSPC liposomes,more » sensitive to heavy metal ions in free solution, maintain similar sensitivity in the gel yet the sensor material can not be recycled.« less

Wet etching technique for fabrication of a high-quality plastic optical fiber sensor.

PubMed

Zhao, Mingfu; Dai, Lang; Zhong, Nianbing; Wang, Zhengkun; Chen, Ming; Li, Bingxin; Luo, Binbin; Tang, Bin; Shi, Shenghui; Song, Tao; Zou, Xue

2017-11-01

In this study, a simple wet etching technique is developed by employing aqueous solutions of acetic acid and ultrasonic irradiation for the fabrication of a high-quality plastic optical fiber (POF) sensor. The effects of acetic acid concentration and temperature and ultrasonic power on the etching rate and surface morphology of the etched POFs are investigated. The transmission spectrum and sensitivity of the etched POF sensors are evaluated using glucose solutions. We discovered that the POF sensors, which are fabricated using an aqueous solution of acetic acid with a concentration of 80 vol. % under an ultrasonic power of 130 W and temperature of 25°C, exhibit good light transmission and a high sensitivity of 9.10  [(RIU)(g/L)] -1 in the glucose solutions.

Exploring plane-symmetric solutions in f(R) gravity

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

Shamir, M. F., E-mail: farasat.shamir@nu.edu.pk

2016-02-15

The modified theories of gravity, especially the f(R) gravity, have attracted much attention in the last decade. This paper is devoted to exploring plane-symmetric solutions in the context of metric f(R) gravity. We extend the work on static plane-symmetric vacuum solutions in f(R) gravity already available in the literature [1, 2]. The modified field equations are solved using the assumptions of both constant and nonconstant scalar curvature. Some well-known solutions are recovered with power-law and logarithmic forms of f(R) models.

Operational method of solution of linear non-integer ordinary and partial differential equations.

PubMed

Zhukovsky, K V

2016-01-01

We propose operational method with recourse to generalized forms of orthogonal polynomials for solution of a variety of differential equations of mathematical physics. Operational definitions of generalized families of orthogonal polynomials are used in this context. Integral transforms and the operational exponent together with some special functions are also employed in the solutions. The examples of solution of physical problems, related to such problems as the heat propagation in various models, evolutional processes, Black-Scholes-like equations etc. are demonstrated by the operational technique.

Influence of uncertainty on framed decision-making with moral dilemma

PubMed Central

Mermillod, Martial; Le Pennec, Jean-Luc; Dutheil, Frédéric; Mondillon, Laurie

2018-01-01

In cases of impending natural disasters, most events are uncertain and emotionally relevant, both critical factors for decision-making. Moreover, for exposed individuals, the sensitivity to the framing of the consequences (gain or loss) and the moral judgments they have to perform (e.g., evacuate or help an injured person) constitute two central effects that have never been examined in the same context of decision-making. In a framed decision-making task with moral dilemma, we investigated whether uncertainty (i.e., unpredictably of events) and a threatening context would influence the framing effect (actions framed in loss are avoided in comparison to the ones framed in gain) and the personal intention effect (unintentional actions are more morally acceptable in comparison to intentional actions) on the perceived moral acceptability of taking action. Considering the impact of uncertainty and fear on the processes underlying these effects, we assumed that these emotions would lead to the negation of the two effects. Our results indicate that the exposure to uncertain events leads to the negation of the framing effect, but does not influence the moral acceptability and the effect of personal intention. We discuss our results in the light of dual-process models (i.e. systematic vs. heuristic), appraisal theories, and neurocognitive aspects. These elements highlight the importance of providing solutions to cope with uncertainty, both for scientists and local populations exposed to natural hazards. PMID:29847589

Influence of uncertainty on framed decision-making with moral dilemma.

PubMed

Merlhiot, Gaëtan; Mermillod, Martial; Le Pennec, Jean-Luc; Dutheil, Frédéric; Mondillon, Laurie

2018-01-01

In cases of impending natural disasters, most events are uncertain and emotionally relevant, both critical factors for decision-making. Moreover, for exposed individuals, the sensitivity to the framing of the consequences (gain or loss) and the moral judgments they have to perform (e.g., evacuate or help an injured person) constitute two central effects that have never been examined in the same context of decision-making. In a framed decision-making task with moral dilemma, we investigated whether uncertainty (i.e., unpredictably of events) and a threatening context would influence the framing effect (actions framed in loss are avoided in comparison to the ones framed in gain) and the personal intention effect (unintentional actions are more morally acceptable in comparison to intentional actions) on the perceived moral acceptability of taking action. Considering the impact of uncertainty and fear on the processes underlying these effects, we assumed that these emotions would lead to the negation of the two effects. Our results indicate that the exposure to uncertain events leads to the negation of the framing effect, but does not influence the moral acceptability and the effect of personal intention. We discuss our results in the light of dual-process models (i.e. systematic vs. heuristic), appraisal theories, and neurocognitive aspects. These elements highlight the importance of providing solutions to cope with uncertainty, both for scientists and local populations exposed to natural hazards.

Mapping Social Ecological Systems Archetypes

NASA Astrophysics Data System (ADS)

Rocha, J. C.; Malmborg, K.; Gordon, L.

2016-12-01

Achieving sustainable development goals requires targeting and monitoring sustainable solutions tailored to different social and ecological contexts. Elinor Ostrom stressed that there is no panaceas or universal solutions to environmental problems, and developed a social-ecological systems' (SES) framework -a nested multi tier set of variables- to help diagnose problems, identify complex interactions, and solutions tailored to each SES arena. However, to our knowledge, the SES framework has only been applied to over a hundred cases, and typically reflect the analysis of local case studies with relatively small coverage in space and time. While case studies are context rich and necessary, their conclusions might not reach policy making instances. Here we develop a data driven method for upscaling Ostrom's SES framework and applied to a context where we expect data is scarce, incomplete, but also where sustainable solutions are badly needed. The purpose of upscaling the framework is to create a tool that facilitates decision making on data scarce environments such as developing countries. We mapped SES by applying the SES framework to poverty alleviation and food security issues in the Volta River basin in Ghana and Burkina Faso. We found archetypical configurations of SES in space given data availability, we study their change over time, and discuss where agricultural innovations such as water reservoirs might have a stronger impact at increasing food security and therefore alleviating poverty and hunger. We conclude outlining how the method can be used in other SES comparative studies.

Usable SPACE: Security, Privacy, and Context for the Mobile User

NASA Astrophysics Data System (ADS)

Jutla, Dawn

Users breach the security of data within many financial applications daily as human and/or business expediency to access and use information wins over corporate security policy guidelines. Recognizing that changing user context often requires different security mechanisms, we discuss end-to-end solutions combining several security and context mechanisms for relevant security control and information presentation in various mobile user situations. We illustrate key concepts using Dimitri Kanevskys (IBM Research) early 2000s patented inventions for voice security and classification.

Modeling Clinical Information Needs in the Context of a Specific Patient

PubMed Central

Price, Susan L.

2000-01-01

Investigators have tried various approaches to link clinical information directly to information sources that may contain answers to clinical questions. Developing a model of clinical information needs that may arise in the context of viewing information about a specific patient is a preliminary step to finding an efficient, useful solution to the information retrieval problem. This poster illustrates a method of modeling clinical information needs in the context of a specific patient that that is adapted from entity-relationship models used in database design.

Optogenetic Inhibition of Ventral Pallidum Neurons Impairs Context-Driven Salt Seeking.

PubMed

Chang, Stephen E; Smedley, Elizabeth B; Stansfield, Katherine J; Stott, Jeffrey J; Smith, Kyle S

2017-06-07

Salt appetite, in which animals can immediately seek out salt when under a novel state of sodium deprivation, is a classic example of how homeostatic systems interface with learned associations to produce an on-the-fly updating of motivated behavior. Neural activity in the ventral pallidum (VP) has been shown to encode changes in the value of salt under such conditions, both the value of salt itself (Tindell et al., 2006) and the motivational value of its predictive cues (Tindell et al., 2009; Robinson and Berridge, 2013). However, it is not known whether the VP is necessary for salt appetite in terms of seeking out salt or consuming salt following sodium depletion. Here, we used a conditioned place-preference procedure to investigate the effects of optogenetically inhibiting the VP on context-driven salt seeking and the consumption of salt following deprivation. Male rats learned to associate one context with sucrose and another context with less-desirable salt. Following sodium depletion, and in the absence of either sucrose or salt, we found that inhibiting the VP selectively reduced the elevation in time spent in the salt-paired context. VP inhibition had minimal effects on the consumption of salt once it was made available. To our knowledge, this is the first evidence that the VP or any brain region is necessary for the ability to use contextual cues to guide salt seeking. These results highlight a dissociation between deficit-driven reward seeking and reward consumption to replenish those deficits, with the former process being particularly sensitive to on-line VP activity. SIGNIFICANCE STATEMENT Salt appetite, in which rats will immediately seek out a once-undesirable concentrated salt solution after being depleted of bodily sodium despite never having tasted salt as a positive reward, is a phenomenon showing how animals can update their motivational goals without any new learning or conditioning. This salt-seeking behavior is also observed when the animal is presented with salt-paired cues. The neural circuitry necessary for context-driven salt-seeking behavior is unknown. We used a novel conditioned place preference procedure to show that optogenetic inhibition of the ventral pallidum (VP), a region known for processing reward, impairs context-driven salt seeking and has minimal effects on the consumption of salt itself following sodium depletion. These results highlight the importance of the VP in context-driven reward-seeking behavior. Copyright © 2017 the authors 0270-6474/17/375670-11$15.00/0.

Theories of hydrophobic effects and the description of free volume in complex liquids

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

Pratt, L.R.; Garde, S.; Hummer, G.

1998-12-31

Recent progress on molecular theories of hydration of nonpolar solutes in liquid aqueous solution has lead to new ways to thinking about the old issue of free volume in liquids. This article surveys the principal new results with particular attention to the context of general issues of packing in liquids.

Contextualising "Education in Pakistan, a White Paper": Global/National Articulations in Education Policy

ERIC Educational Resources Information Center

Lingard, Bob; Ali, Sajid

2009-01-01

This article contextualises "Education in Pakistan, a White Paper" (2007), an influential education policy paper in Pakistan. The focus is on the ways the White Paper constructs its own contexts as a complement to the policy solutions proffered. Here we recognise Seddon's point about the discursive work of policy in constructing context.…

A Sampled Literature Review of Design-Based Learning Approaches: A Search for Key Characteristics

ERIC Educational Resources Information Center

Gómez Puente, Sonia M.; van Eijck, Michiel; Jochems, Wim

2013-01-01

Design-based learning (DBL) is an educational approach grounded in the processes of inquiry and reasoning towards generating innovative artifacts, systems and solutions. The approach is well characterized in the context of learning natural sciences in secondary education. Less is known, however, of its characteristics in the context of higher…

Digital Footprints in the Context of Professional Ethics

ERIC Educational Resources Information Center

Kligiene, Stanislava Nerute

2012-01-01

The paper surveys the risks and benefits which the user faces in the networked environment and how those challenges can be overcome. The question is how to measure the potential or benefits of such a complex phenomenon--the collaborative cross-domains in social media. As one of the solutions we propose to consider this in the context of digital…

Electron-rich triphenylamine-based sensors for picric acid detection.

PubMed

Chowdhury, Aniket; Mukherjee, Partha Sarathi

2015-04-17

This paper demonstrates the role of solvent in selectivity and sensitivity of a series of electron-rich compounds for the detection of trace amounts of picric acid. Two new electron-rich fluorescent esters (6, 7) containing a triphenylamine backbone as well as their analogous carboxylic acids (8, 9) have been synthesized and characterized. Fluorescent triphenylamine coupled with an ethynyl moiety constitutes π-electron-rich selective and sensitive probes for electron-deficient picric acid (PA). In solution, the high sensitivity of all the sensors toward PA can be attributed to a combined effect of the ground-state charge-transfer complex formation and resonance energy transfer between the sensor and analyte. The acids 8 and 9 also showed enhanced sensitivity for nitroaromatics in the solid state, and their enhanced sensitivity could be attributed to exciton migration due to close proximity of the neighboring acid molecules, as evident from the X-ray diffraction study. The compounds were found to be quite sensitive for the detection of trace amount of nitroaromatics in solution, solid, and contact mode.

Social Representation of Dementia and Its Influence on the Search for Early Care by Family Member Caregivers.

PubMed

Juárez-Cedillo, Teresa; Jarillo-Soto, Edgar C; Rosas-Carrasco, Oscar

2014-06-01

Social representations (SRs) contain 3 dimensions: information, attitude, and field. These affect the recognition of the first symptoms of dementia by the patient's caregiver. This study focused on the period from the first signs of cognitive difficulties to the diagnosis of dementia. Eight caregivers of elderly patients with dementia were interviewed to construct their SRs regarding dementia and how this influences seeking medical treatment during the first stages of the disease. Social representations were analyzed through a structural focus, based on the content analysis. Decision making is related to knowledge about dementia, attitude (emotions and sensitivity), and the concept of the caregiver about the relative with dementia. The results confirm the importance of the symbolic dimension of personal experience in managing care and seeking medical treatment. The presence of dementia in the family creates interpersonal dilemmas that caregivers experience. The solutions are framed in the sociocultural context. © The Author(s) 2013.

Security, safety, and related technology - the triangle of eHealth service provision.

PubMed

Savastano, Mario; Hovsto, Asbjorn; Pharow, Peter; Blobel, Bernd

2008-01-01

The developing of innovative solutions in the emerging eHealth market requires strong economic efforts which may be justified only in presence of particularly suitable boundary conditions. Among the factors retained of primary importance for the development of eHealth, a correct approach to id-management is unanimously considered fundamental. Three keywords in the id-management context appear particularly important: standardization, security and safety. Standardization may contribute to increase the size and duration of the eHealth market, while security and safety may encourage all the stakeholders to trust in a appropriate and safe management of all the very sensitive personal data involved in the eHealth applications. The aim of the present paper is analyzing some security and safety issues in eHealth from the particular prospective of the identity management and standardization. The paper highlights the mission of the EU funded "BioHealth" project whose mission is to increase the stakeholders' knowledge about existing and emerging standards in eHealth with particular reference to identity management.

Mediation of donor–acceptor distance in an enzymatic methyl transfer reaction

PubMed Central

Zhang, Jianyu; Kulik, Heather J.; Martinez, Todd J.; Klinman, Judith P.

2015-01-01

Enzymatic methyl transfer, catalyzed by catechol-O-methyltransferase (COMT), is investigated using binding isotope effects (BIEs), time-resolved fluorescence lifetimes, Stokes shifts, and extended graphics processing unit (GPU)-based quantum mechanics/molecular mechanics (QM/MM) approaches. The WT enzyme is compared with mutants at Tyr68, a conserved residue that is located behind the reactive sulfur of cofactor. Small (>1) BIEs are observed for an S-adenosylmethionine (AdoMet)-binary and abortive ternary complex containing 8-hydroxyquinoline, and contrast with previously reported inverse (<1) kinetic isotope effects (KIEs). Extended GPU-based computational studies of a ternary complex containing catecholate show a clear trend in ground state structures, from noncanonical bond lengths for WT toward solution values with mutants. Structural and dynamical differences that are sensitive to Tyr68 have also been detected using time-resolved Stokes shift measurements and molecular dynamics. These experimental and computational results are discussed in the context of active site compaction that requires an ionization of substrate within the enzyme ternary complex. PMID:26080432

NAIMA as a solution for future GMO diagnostics challenges.

PubMed

Dobnik, David; Morisset, Dany; Gruden, Kristina

2010-03-01

In the field of genetically modified organism (GMO) diagnostics, real-time PCR has been the method of choice for target detection and quantification in most laboratories. Despite its numerous advantages, however, the lack of a true multiplexing option may render real-time PCR less practical in the face of future GMO detection challenges such as the multiplicity and increasing complexity of new transgenic events, as well as the repeated occurrence of unauthorized GMOs on the market. In this context, we recently reported the development of a novel multiplex quantitative DNA-based target amplification method, named NASBA implemented microarray analysis (NAIMA), which is suitable for sensitive, specific and quantitative detection of GMOs on a microarray. In this article, the performance of NAIMA is compared with that of real-time PCR, the focus being their performances in view of the upcoming challenge to detect/quantify an increasing number of possible GMOs at a sustainable cost and affordable staff effort. Finally, we present our conclusions concerning the applicability of NAIMA for future use in GMO diagnostics.

Sensor-agnostic photogrammetric image registration with applications to population modeling

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

White, Devin A; Moehl, Jessica J

2016-01-01

Photogrammetric registration of airborne and spaceborne imagery is a crucial prerequisite to many data fusion tasks. While embedded sensor models provide a rough geolocation estimate, these metadata may be incomplete or imprecise. Manual solutions are appropriate for small-scale projects, but for rapid streams of cross-modal, multi-sensor, multi-temporal imagery with varying metadata standards, an automated approach is required. We present a high-performance image registration workflow to address this need. This paper outlines the core development concepts and demonstrates its utility with respect to the 2016 data fusion contest imagery. In particular, Iris ultra-HD video is georeferenced to the Earth surface viamore » registration to DEIMOS-2 imagery, which serves as a trusted control source. Geolocation provides opportunity to augment the video with spatial context, stereo-derived disparity, spectral sensitivity, change detection, and numerous ancillary geospatial layers. We conclude by leveraging these derivative data layers towards one such fusion application: population distribution modeling.« less

How to find future ecstasy-users: targeted and snowball sampling in an ethically sensitive context.

PubMed

Vervaeke, Hylke K E; Korf, Dirk J; Benschop, Annemieke; van den Brink, Wim

2007-08-01

This article documents the design and the sampling procedures of a prospective longitudinal multidisciplinary study on the neurotoxicity of ecstasy (MDMA): the Netherlands XTC Toxicity Study (NeXT). Targeted and snowball sampling was used to recruit 188 respondents who were ecstasy-naive at baseline. All respondents completed baseline questionnaires and underwent medical and neuropsychological examinations. At the end of a 11- to 26- month follow-up period in which they completed four additional questionnaires, 160 respondents remained (85.1%). A total of 65 participants (40.6%) took ecstasy for the first time during the follow-up period. This paper discusses the ethical dilemmas inherent in a study of this type and the specific problems and solutions that emerged in the sampling. The sampling was tightly constrained by our need to locate respondents who were potential future ecstasy users while also meeting strict medical and technical criteria. The 'intention to use' criterion proved to be a clear-cut inclusion rule that was practical to apply in the fieldwork.

Knowledge creation through total clinical outcomes management: a practice-based evidence solution to address some of the challenges of knowledge translation.

PubMed

Lyons, John S

2009-02-01

The challenges of knowledge translation in behavioural health care are unique to this field for a variety of reasons including the fact that effective treatment is invariably embedded in a strong relationship between practitioners and the people they serve. Practitioners' knowledge gained from experience and intuition become an even more important consideration in the knowledge translation process since clinicians are, in fact, a component of most treatments. Communication of findings from science must be conceptualized with sensitivity to this reality. Considering knowledge translation as a communication process suggests the application of contemporary theories of communication which emphasize the creation of shared meaning over the transmission of knowledge from one person to the next. In this context outcomes management approaches to create a learning environment within clinical practices that facilitate the goals of knowledge transfer while respecting that the scientific enterprise is neither the sole nor primary repository of knowledge.

Paradise lost: A study of the decline of institutions and the restructuring of organizational fields in the United States power industry

NASA Astrophysics Data System (ADS)

Sine, Wesley David

Institutional theorists have a long tradition of examining the persistence organizational forms and practices. Most institutional analysis, however, fails to discuss change in organizational forms and practices that at one time were highly taken for granted. This dissertation presents three papers that explore questions of institutional change in the context of the evolving power industry. The first paper, Dimensions of Institutional Resistance to Change, examines the qualities that make institutions more or less resistant to change. This paper surveys the literature on institutional change and suggests four institutional qualities for indexing institutional change: taken for grantedness, diffuseness, symbolic value, and integrativeness. I argue that these qualities can be used to measure the extent to which an institution is resistant to change, thus providing a means for studying and predicting the life spans of institutions. The second paper, From Hierarchies to Markets: The Deregulation of the Electric Generating Industry, uses the dimensions proposed in the first paper to understand the structural changes in the electric utility industry between 1935 and 1978. It theorizes that crisis catalyzes both organizational scrutiny, which erodes institutional symbolic value and taken-for-grantedness, and search processes for solutions, which redefine fringe alternatives within an institutional field as possible solutions. The net result is the delegitimation of incumbent institutions and the recognition of alternative solutions, creating a solution bazaar, where solutions compete to solve organizational inefficiencies made relevant by the crisis. The third paper, The Institutional Context of Founding Variation in the Emerging Independent Power Industry, presents and tests a theory of the effects of institutional structures on the genesis, development, and variation of organizational forms in a newborn industry created by radical regulatory change. Nascent industries formed by punctuated change are particularly susceptible to institutional influences. Normative, regulative, and cognitive structures form the context that shape entrepreneurial decisions about organizational foundings. Institutional structures can either increase or decrease barriers to entry into nascent industries, thus influencing the heterogeneity of organizational forms founded within the niche. These propositions are examined and tested in the context of the independent power industry.

6.5% efficient perovskite quantum-dot-sensitized solar cell.

PubMed

Im, Jeong-Hyeok; Lee, Chang-Ryul; Lee, Jin-Wook; Park, Sang-Won; Park, Nam-Gyu

2011-10-05

Highly efficient quantum-dot-sensitized solar cell is fabricated using ca. 2-3 nm sized perovskite (CH(3)NH(3))PbI(3) nanocrystal. Spin-coating of the equimolar mixture of CH(3)NH(3)I and PbI(2) in γ-butyrolactone solution (perovskite precursor solution) leads to (CH(3)NH(3))PbI(3) quantum dots (QDs) on nanocrystalline TiO(2) surface. By electrochemical junction with iodide/iodine based redox electrolyte, perovskite QD-sensitized 3.6 μm-thick TiO(2) film shows maximum external quantum efficiency (EQE) of 78.6% at 530 nm and solar-to-electrical conversion efficiency of 6.54% at AM 1.5G 1 sun intensity (100 mW cm(-2)), which is by far the highest efficiency among the reported inorganic quantum dot sensitizers.

Quantization of the Szekeres system

NASA Astrophysics Data System (ADS)

Paliathanasis, A.; Zampeli, Adamantia; Christodoulakis, T.; Mustafa, M. T.

2018-06-01

We study the quantum corrections on the Szekeres system in the context of canonical quantization in the presence of symmetries. We start from an effective point-like Lagrangian with two integrals of motion, one corresponding to the Hamiltonian and the other to a second rank killing tensor. Imposing their quantum version on the wave function results to a solution which is then interpreted in the context of Bohmian mechanics. In this semiclassical approach, it is shown that there is no quantum corrections, thus the classical trajectories of the Szekeres system are not affected at this level. Finally, we define a probability function which shows that a stationary surface of the probability corresponds to a classical exact solution.

Context-sensitive patch histograms for detecting rare events in histopathological data

NASA Astrophysics Data System (ADS)

Diaz, Kristians; Baust, Maximilian; Navab, Nassir

2017-03-01

Assessment of histopathological data is not only difficult due to its varying appearance, e.g. caused by staining artifacts, but also due to its sheer size: Common whole slice images feature a resolution of 6000x4000 pixels. Therefore, finding rare events in such data sets is a challenging and tedious task and developing sophisticated computerized tools is not easy, especially when no or little training data is available. In this work, we propose learning-free yet effective approach based on context sensitive patch-histograms in order to find extramedullary hematopoiesis events in Hematoxylin-Eosin-stained images. When combined with a simple nucleus detector, one can achieve performance levels in terms of sensitivity 0.7146, specificity 0.8476 and accuracy 0.8353 which are very well comparable to a recently published approach based on random forests.

Context-sensitive design and human interaction principles for usable, useful, and adoptable radars

NASA Astrophysics Data System (ADS)

McNamara, Laura A.; Klein, Laura M.

2016-05-01

The evolution of exquisitely sensitive Synthetic Aperture Radar (SAR) systems is positioning this technology for use in time-critical environments, such as search-and-rescue missions and improvised explosive device (IED) detection. SAR systems should be playing a keystone role in the United States' Intelligence, Surveillance, and Reconnaissance activities. Yet many in the SAR community see missed opportunities for incorporating SAR into existing remote sensing data collection and analysis challenges. Drawing on several years' of field research with SAR engineering and operational teams, this paper examines the human and organizational factors that mitigate against the adoption and use of SAR for tactical ISR and operational support. We suggest that SAR has a design problem, and that context-sensitive, human and organizational design frameworks are required if the community is to realize SAR's tactical potential.

An International Model for Antibiotics Regulation.

PubMed

Aguirre, Emilie

We face a global antibiotics resistance crisis. Antibiotic drugs are rapidly losing their effectiveness, potentially propelling us toward a post-antibiotic world. The largest use of antibiotics in the world is in food-producing animals. Food producers administer these drugs in routine, low doses—the types of doses that are incidentally the most conducive to breeding antibiotic resistance. In general, individual countries have been too slow to act in regulating misuse and overuse of antibiotics in foodproducing animals. This problem will only worsen with the significant projected growth in meat consumption and production expected in emerging economies in the near future. Although individual countries regulating antibiotics can have important effects, one country alone cannot insulate itself entirely from the effects of antibiotic resistance, nor can one country solve the crisis for itself or for the world. The global nature of the food system and the urgency of the problem require immediate global solutions. Adapting a democratic experimentalist approach at the international level can help achieve this goal. Using an international democratic experimentalist framework in conjunction with the World Organization for Animal Health (OIE) would provide for increased systematized data collection and lead to heightened, scientifically informed OIE standards, enforceable by the World Trade Organization (WTO), which could have a significant impact on the reduction of subtherapeutic use of antibiotics internationally. International democratic experimentalism addresses the global intricacy, time sensitivity, context- and culture-specificity, and knowledgeintensiveness of this problem. By encouraging more countries to experiment to solve this problem, the democratic experimentalist model would help develop a larger database of solutions to enable more meaningful cross-country comparisons across a wider range of contexts. This approach maintains democratic governance and legitimacy while maximizing data collection, efficiency, translatability, transparency, and information-sharing. Adapting democratic experimentalism internationally can enable the kind of concerted international effort required to address the pressing problem of antibiotic resistance.

Health Information System in a Cloud Computing Context.

PubMed

Sadoughi, Farahnaz; Erfannia, Leila

2017-01-01

Healthcare as a worldwide industry is experiencing a period of growth based on health information technology. The capabilities of cloud systems make it as an option to develop eHealth goals. The main objectives of the present study was to evaluate the advantages and limitations of health information systems implementation in a cloud-computing context that was conducted as a systematic review in 2016. Science direct, Scopus, Web of science, IEEE, PubMed and Google scholar were searched according study criteria. Among 308 articles initially found, 21 articles were entered in the final analysis. All the studies had considered cloud computing as a positive tool to help advance health technology, but none had insisted too much on its limitations and threats. Electronic health record systems have been mostly studied in the fields of implementation, designing, and presentation of models and prototypes. According to this research, the main advantages of cloud-based health information systems could be categorized into the following groups: economic benefits and advantages of information management. The main limitations of the implementation of cloud-based health information systems could be categorized into the 4 groups of security, legal, technical, and human restrictions. Compared to earlier studies, the present research had the advantage of dealing with the issue of health information systems in a cloud platform. The high frequency of studies conducted on the implementation of cloud-based health information systems revealed health industry interest in the application of this technology. Security was a subject discussed in most studies due to health information sensitivity. In this investigation, some mechanisms and solutions were discussed concerning the mentioned systems, which would provide a suitable area for future scientific research on this issue. The limitations and solutions discussed in this systematic study would help healthcare managers and decision-makers take better and more efficient advantages of this technology and make better planning to adopt cloud-based health information systems.

(U) Second-Order Sensitivity Analysis of Uncollided Particle Contributions to Radiation Detector Responses Using Ray-Tracing

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

Favorite, Jeffrey A.

The Second-Level Adjoint Sensitivity System (2nd-LASS) that yields the second-order sensitivities of a response of uncollided particles with respect to isotope densities, cross sections, and source emission rates is derived in Refs. 1 and 2. In Ref. 2, we solved problems for the uncollided leakage from a homogeneous sphere and a multiregion cylinder using the PARTISN multigroup discrete-ordinates code. In this memo, we derive solutions of the 2nd-LASS for the particular case when the response is a flux or partial current density computed at a single point on the boundary, and the inner products are computed using ray-tracing. Both themore » PARTISN approach and the ray-tracing approach are implemented in a computer code, SENSPG. The next section of this report presents the equations of the 1st- and 2nd-LASS for uncollided particles and the first- and second-order sensitivities that use the solutions of the 1st- and 2nd-LASS. Section III presents solutions of the 1st- and 2nd-LASS equations for the case of ray-tracing from a detector point. Section IV presents specific solutions of the 2nd-LASS and derives the ray-trace form of the inner products needed for second-order sensitivities. Numerical results for the total leakage from a homogeneous sphere are presented in Sec. V and for the leakage from one side of a two-region slab in Sec. VI. Section VII is a summary and conclusions.« less

Perceptual context and individual differences in the language proficiency of preschool children.

PubMed

Banai, Karen; Yifat, Rachel

2016-02-01

Although the contribution of perceptual processes to language skills during infancy is well recognized, the role of perception in linguistic processing beyond infancy is not well understood. In the experiments reported here, we asked whether manipulating the perceptual context in which stimuli are presented across trials influences how preschool children perform visual (shape-size identification; Experiment 1) and auditory (syllable identification; Experiment 2) tasks. Another goal was to determine whether the sensitivity to perceptual context can explain part of the variance in oral language skills in typically developing preschool children. Perceptual context was manipulated by changing the relative frequency with which target visual (Experiment 1) and auditory (Experiment 2) stimuli were presented in arrays of fixed size, and identification of the target stimuli was tested. Oral language skills were assessed using vocabulary, word definition, and phonological awareness tasks. Changes in perceptual context influenced the performance of the majority of children on both identification tasks. Sensitivity to perceptual context accounted for 7% to 15% of the variance in language scores. We suggest that context effects are an outcome of a statistical learning process. Therefore, the current findings demonstrate that statistical learning can facilitate both visual and auditory identification processes in preschool children. Furthermore, consistent with previous findings in infants and in older children and adults, individual differences in statistical learning were found to be associated with individual differences in language skills of preschool children. Copyright © 2015 Elsevier Inc. All rights reserved.

Cellular, molecular, and epigenetic mechanisms in non-associative conditioning: implications for pain and memory.

PubMed

Rahn, Elizabeth J; Guzman-Karlsson, Mikael C; David Sweatt, J

2013-10-01

Sensitization is a form of non-associative conditioning in which amplification of behavioral responses can occur following presentation of an aversive or noxious stimulus. Understanding the cellular and molecular underpinnings of sensitization has been an overarching theme spanning the field of learning and memory as well as that of pain research. In this review we examine how sensitization, both in the context of learning as well as pain processing, shares evolutionarily conserved behavioral, cellular/synaptic, and epigenetic mechanisms across phyla. First, we characterize the behavioral phenomenon of sensitization both in invertebrates and vertebrates. Particular emphasis is placed on long-term sensitization (LTS) of withdrawal reflexes in Aplysia following aversive stimulation or injury, although additional invertebrate models are also covered. In the context of vertebrates, sensitization of mammalian hyperarousal in a model of post-traumatic stress disorder (PTSD), as well as mammalian models of inflammatory and neuropathic pain is characterized. Second, we investigate the cellular and synaptic mechanisms underlying these behaviors. We focus our discussion on serotonin-mediated long-term facilitation (LTF) and axotomy-mediated long-term hyperexcitability (LTH) in reduced Aplysia systems, as well as mammalian spinal plasticity mechanisms of central sensitization. Third, we explore recent evidence implicating epigenetic mechanisms in learning- and pain-related sensitization. This review illustrates the fundamental and functional overlay of the learning and memory field with the pain field which argues for homologous persistent plasticity mechanisms in response to sensitizing stimuli or injury across phyla. Copyright © 2013 Elsevier Inc. All rights reserved.

Monoamine-Sensitive Developmental Periods Impacting Adult Emotional and Cognitive Behaviors

PubMed Central

Suri, Deepika; Teixeira, Cátia M; Cagliostro, Martha K Caffrey; Mahadevia, Darshini; Ansorge, Mark S

2015-01-01

Development passes through sensitive periods, during which plasticity allows for genetic and environmental factors to exert indelible influence on the maturation of the organism. In the context of central nervous system development, such sensitive periods shape the formation of neurocircuits that mediate, regulate, and control behavior. This general mechanism allows for development to be guided by both the genetic blueprint as well as the environmental context. While allowing for adaptation, such sensitive periods are also vulnerability windows during which external and internal factors can confer risk to disorders by derailing otherwise resilient developmental programs. Here we review developmental periods that are sensitive to monoamine signaling and impact adult behaviors of relevance to psychiatry. Specifically, we review (1) a serotonin-sensitive period that impacts sensory system development, (2) a serotonin-sensitive period that impacts cognition, anxiety- and depression-related behaviors, and (3) a dopamine- and serotonin-sensitive period affecting aggression, impulsivity and behavioral response to psychostimulants. We discuss preclinical data to provide mechanistic insight, as well as epidemiological and clinical data to point out translational relevance. The field of translational developmental neuroscience has progressed exponentially providing solid conceptual advances and unprecedented mechanistic insight. With such knowledge at hand and important methodological innovation ongoing, the field is poised for breakthroughs elucidating the developmental origins of neuropsychiatric disorders, and thus understanding pathophysiology. Such knowledge of sensitive periods that determine the developmental trajectory of complex behaviors is a necessary step towards improving prevention and treatment approaches for neuropsychiatric disorders. PMID:25178408

Novel salicylic acid-oriented thiourea-type receptors as colorimetric chemosensor: Synthesis, characterizations and selective naked-eye recognition properties

NASA Astrophysics Data System (ADS)

Li, Shaowei; Cao, Xiufang; Chen, Changshui; Ke, Shaoyong

2012-10-01

Based on the salicylic acid backbone, three highly sensitive and selective colorimetric chemosensors with an acylthiourea binding unit have been designed, synthesized and characterized. These chemosensors have been utilized for selective recognition of fluoride anions in dry DMSO solution by typical spectroscopic titration techniques. Furthermore, the obtained chemosensors AR1-3 have shown naked-eye sensitivity for detection of biologically important fluoride ion over other anions in solution.

Using solute and heat tracers for aquifer characterization in a strongly heterogeneous alluvial aquifer

NASA Astrophysics Data System (ADS)

Sarris, Theo S.; Close, Murray; Abraham, Phillip

2018-03-01

A test using Rhodamine WT and heat as tracers, conducted over a 78 day period in a strongly heterogeneous alluvial aquifer, was used to evaluate the utility of the combined observation dataset for aquifer characterization. A highly parameterized model was inverted, with concentration and temperature time-series as calibration targets. Groundwater heads recorded during the experiment were boundary dependent and were ignored during the inversion process. The inverted model produced a high resolution depiction of the hydraulic conductivity and porosity fields. Statistical properties of these fields are in very good agreement with estimates from previous studies at the site. Spatially distributed sensitivity analysis suggests that both solute and heat transport were most sensitive to the hydraulic conductivity and porosity fields and less sensitive to dispersivity and thermal distribution factor, with sensitivity to porosity greatly reducing outside the monitored area. The issues of model over-parameterization and non-uniqueness are addressed through identifiability analysis. Longitudinal dispersivity and thermal distribution factor are highly identifiable, however spatially distributed parameters are only identifiable near the injection point. Temperature related density effects became observable for both heat and solute, as the temperature anomaly increased above 12 degrees centigrade, and affected down gradient propagation. Finally we demonstrate that high frequency and spatially dense temperature data cannot inform a dual porosity model in the absence of frequent solute concentration measurements.

In the face of fear: Anxiety sensitizes defensive responses to fearful faces

PubMed Central

Grillon, Christian; Charney, Danielle R.

2011-01-01

Fearful faces readily activate the amygdala. Yet, whether fearful faces evoke fear is unclear. Startle studies show no potentiation of startle by fearful faces, suggesting that such stimuli do not activate defense mechanisms. However, the response to biologically relevant stimuli may be sensitized by anxiety. The present study tested the hypothesis that startle would not be potentiated by fearful faces in a safe context, but that startle would be larger during fearful faces compared to neutral faces in a threat-of-shock context. Subjects viewed fearful and neutral faces in alternating periods of safety and threat of shock. Acoustic startle stimuli were presented in the presence and absence of the faces. Startle was transiently potentiated by fearful faces compared to neutral faces in the threat periods. This suggests that although fearful faces do not prompt behavioral mobilization in an innocuous context, they can do so in an anxiogenic one. PMID:21824155

A dictionary server for supplying context sensitive medical knowledge.

PubMed Central

Ruan, W.; Bürkle, T.; Dudeck, J.

2000-01-01

The Giessen Data Dictionary Server (GDDS), developed at Giessen University Hospital, integrates clinical systems with on-line, context sensitive medical knowledge to help with making medical decisions. By "context" we mean the clinical information that is being presented at the moment the information need is occurring. The dictionary server makes use of a semantic network supported by a medical data dictionary to link terms from clinical applications to their proper information sources. It has been designed to analyze the network structure itself instead of knowing the layout of the semantic net in advance. This enables us to map appropriate information sources to various clinical applications, such as nursing documentation, drug prescription and cancer follow up systems. This paper describes the function of the dictionary server and shows how the knowledge stored in the semantic network is used in the dictionary service. PMID:11079978

Cultural Considerations in Adolescent Suicide Prevention and Psychosocial Treatment

PubMed Central

Goldston, David B.; Molock, Sherry Davis; Whitbeck, Leslie B.; Murakami, Jessica L.; Zayas, Luis H.; Nagayama Hall, Gordon C.

2009-01-01

Ethnic groups differ in rates of suicidal behaviors among youths, the context within which suicidal behavior occurs (e.g., different precipitants, vulnerability and protective factors, and reactions to suicidal behaviors), and patterns of help-seeking. In this article, the authors discuss the cultural context of suicidal behavior among African American, American Indian and Alaska Native, Asian American and Pacific Islander, and Latino adolescents, and the implications of these contexts for suicide prevention and treatment. Several cross-cutting issues are discussed, including acculturative stress and protective factors within cultures; the roles of religion and spirituality and the family in culturally sensitive interventions; different manifestations and interpretations of distress in different cultures; and the impact of stigma and cultural distrust on help-seeking. The needs for culturally sensitive and community-based interventions are discussed, along with future opportunities for research in intervention development and evaluation. PMID:18193978

Smarter Earth Science Data System

NASA Technical Reports Server (NTRS)

Huang, Thomas

2013-01-01

The explosive growth in Earth observational data in the recent decade demands a better method of interoperability across heterogeneous systems. The Earth science data system community has mastered the art in storing large volume of observational data, but it is still unclear how this traditional method scale over time as we are entering the age of Big Data. Indexed search solutions such as Apache Solr (Smiley and Pugh, 2011) provides fast, scalable search via keyword or phases without any reasoning or inference. The modern search solutions such as Googles Knowledge Graph (Singhal, 2012) and Microsoft Bing, all utilize semantic reasoning to improve its accuracy in searches. The Earth science user community is demanding for an intelligent solution to help them finding the right data for their researches. The Ontological System for Context Artifacts and Resources (OSCAR) (Huang et al., 2012), was created in response to the DARPA Adaptive Vehicle Make (AVM) programs need for an intelligent context models management system to empower its terrain simulation subsystem. The core component of OSCAR is the Environmental Context Ontology (ECO) is built using the Semantic Web for Earth and Environmental Terminology (SWEET) (Raskin and Pan, 2005). This paper presents the current data archival methodology within a NASA Earth science data centers and discuss using semantic web to improve the way we capture and serve data to our users.

A mechanistic pan-cancer pathway model informed by multi-omics data interprets stochastic cell fate responses to drugs and mitogens

PubMed Central

Bouhaddou, Mehdi; Koch, Rick J.; DiStefano, Matthew S.; Tan, Annie L.; Mertz, Alex E.

2018-01-01

Most cancer cells harbor multiple drivers whose epistasis and interactions with expression context clouds drug and drug combination sensitivity prediction. We constructed a mechanistic computational model that is context-tailored by omics data to capture regulation of stochastic proliferation and death by pan-cancer driver pathways. Simulations and experiments explore how the coordinated dynamics of RAF/MEK/ERK and PI-3K/AKT kinase activities in response to synergistic mitogen or drug combinations control cell fate in a specific cellular context. In this MCF10A cell context, simulations suggest that synergistic ERK and AKT inhibitor-induced death is likely mediated by BIM rather than BAD, which is supported by prior experimental studies. AKT dynamics explain S-phase entry synergy between EGF and insulin, but simulations suggest that stochastic ERK, and not AKT, dynamics seem to drive cell-to-cell proliferation variability, which in simulations is predictable from pre-stimulus fluctuations in C-Raf/B-Raf levels. Simulations suggest MEK alteration negligibly influences transformation, consistent with clinical data. Tailoring the model to an alternate cell expression and mutation context, a glioma cell line, allows prediction of increased sensitivity of cell death to AKT inhibition. Our model mechanistically interprets context-specific landscapes between driver pathways and cell fates, providing a framework for designing more rational cancer combination therapy. PMID:29579036

Children's Play in Diverse Cultures. Children's Play in Society Series.

ERIC Educational Resources Information Center

Roopnarine, Jaipaul L., Ed.; And Others

This book illuminates play as a universal and culture-specific activity. It provides needed information about the behavior of children in diverse cultural contexts as well as about the play of children in unassimilated cultural or subcultural contexts. It offers readers the opportunity to develop greater sensitivity to and better understanding of…

The Experience of Daily Hassles, Cardiovascular Reactivity and Adolescent Risk Taking and Self-Esteem

ERIC Educational Resources Information Center

Vermeersch, Hans; T'Sjoen, Guy; Kaufman, Jean-Marc; Vincke, John; Bracke, Piet

2010-01-01

Based on Boyce and Ellis's model on "context" and "biological sensitivity to the context", this article analyzes the interaction between the experience of daily hassles and experimentally induced cardiovascular reactivity as an indicator of stress reactivity, in explaining risk taking and self-esteem. This study found, in a…

Using Design-Based Research in Gifted Education

ERIC Educational Resources Information Center

Jen, Enyi; Moon, Sidney; Samarapungavan, Ala

2015-01-01

Design-based research (DBR) is a new methodological framework that was developed in the context of the learning sciences; however, it has not been used very often in the field of gifted education. Compared with other methodologies, DBR is more process-oriented and context-sensitive. In this methodological brief, the authors introduce DBR and…

Empirical ethics, context-sensitivity, and contextualism.

PubMed

Musschenga, Albert W

2005-10-01

In medical ethics, business ethics, and some branches of political philosophy (multi-culturalism, issues of just allocation, and equitable distribution) the literature increasingly combines insights from ethics and the social sciences. Some authors in medical ethics even speak of a new phase in the history of ethics, hailing "empirical ethics" as a logical next step in the development of practical ethics after the turn to "applied ethics." The name empirical ethics is ill-chosen because of its associations with "descriptive ethics." Unlike descriptive ethics, however, empirical ethics aims to be both descriptive and normative. The first question on which I focus is what kind of empirical research is used by empirical ethics and for which purposes. I argue that the ultimate aim of all empirical ethics is to improve the context-sensitivity of ethics. The second question is whether empirical ethics is essentially connected with specific positions in meta-ethics. I show that in some kinds of meta-ethical theories, which I categorize as broad contextualist theories, there is an intrinsic need for connecting normative ethics with empirical social research. But context-sensitivity is a goal that can be aimed for from any meta-ethical position.

Long-Term Memories Bias Sensitivity and Target Selection in Complex Scenes

PubMed Central

Patai, Eva Zita; Doallo, Sonia; Nobre, Anna Christina

2014-01-01

In everyday situations we often rely on our memories to find what we are looking for in our cluttered environment. Recently, we developed a new experimental paradigm to investigate how long-term memory (LTM) can guide attention, and showed how the pre-exposure to a complex scene in which a target location had been learned facilitated the detection of the transient appearance of the target at the remembered location (Summerfield, Lepsien, Gitelman, Mesulam, & Nobre, 2006; Summerfield, Rao, Garside, & Nobre, 2011). The present study extends these findings by investigating whether and how LTM can enhance perceptual sensitivity to identify targets occurring within their complex scene context. Behavioral measures showed superior perceptual sensitivity (d′) for targets located in remembered spatial contexts. We used the N2pc event-related potential to test whether LTM modulated the process of selecting the target from its scene context. Surprisingly, in contrast to effects of visual spatial cues or implicit contextual cueing, LTM for target locations significantly attenuated the N2pc potential. We propose that the mechanism by which these explicitly available LTMs facilitate perceptual identification of targets may differ from mechanisms triggered by other types of top-down sources of information. PMID:23016670

Exploratory rearing: a context- and stress-sensitive behavior recorded in the open-field test.

PubMed

Sturman, Oliver; Germain, Pierre-Luc; Bohacek, Johannes

2018-02-16

Stressful experiences are linked to anxiety disorders in humans. Similar effects are observed in rodent models, where anxiety is often measured in classic conflict tests such as the open-field test. Spontaneous rearing behavior, in which rodents stand on their hind legs to explore, can also be observed in this test yet is often ignored. We define two forms of rearing, supported rearing (in which the animal rears against the walls of the arena) and unsupported rearing (in which the animal rears without contacting the walls of the arena). Using an automated open-field test, we show that both rearing behaviors appear to be strongly context dependent and show clear sex differences, with females rearing less than males. We show that unsupported rearing is sensitive to acute stress, and is reduced under more averse testing conditions. Repeated testing and handling procedures lead to changes in several parameters over varying test sessions, yet unsupported rearing appears to be rather stable within a given animal. Rearing behaviors could therefore provide an additional measure of anxiety in rodents relevant for behavioral studies, as they appear to be highly sensitive to context and may be used in repeated testing designs.

Characteristics of TiO2/ZnO bilayer film towards pH sensitivity prepared by different spin coating deposition process

NASA Astrophysics Data System (ADS)

Rahman, Rohanieza Abdul; Zulkefle, Muhammad Al Hadi; Abdullah, Wan Fazlida Hanim; Rusop, M.; Herman, Sukreen Hana

2016-07-01

In this study, titanium dioxide (TiO2) and zinc oxide (ZnO) bilayer film for pH sensing application will be presented. TiO2/ZnO bilayer film with different speed of spin-coating process was deposited on Indium Tin Oxide (ITO), prepared by sol-gel method. This fabricated bilayer film was used as sensing membrane for Extended Gate Field-Effect Transistor (EGFET) for pH sensing application. Experimental results indicated that the sensor is able to detect the sensitivity towards pH buffer solution. In order to obtained the result, sensitivity measurement was done by using the EGFET setup equipment with constant-current (100 µA) and constant-voltage (0.3 V) biasing interfacing circuit. TiO2/ZnO bilayer film which the working electrode, act as the pH-sensitive membrane was connected to a commercial metal-oxide semiconductor FET (MOSFET). This MOSFET then was connected to the interfacing circuit. The sensitivity of the TiO2 thin film towards pH buffer solution was measured by dipping the sensing membrane in pH4, pH7 and pH10 buffer solution. These thin films were characterized by using Field Emission Scanning Electron Microscope (FESEM) to obtain the surface morphology of the composite bilayer films. In addition, I-V measurement was done in order to determine the electrical properties of the bilayer films. According to the result obtained in this experiment, bilayer film that spin at 4000 rpm, gave highest sensitivity which is 52.1 mV/pH. Relating the I-V characteristic of the thin films and sensitivity, the sensing membrane with higher conductivity gave better sensitivity.

Characteristics of TiO{sub 2}/ZnO bilayer film towards pH sensitivity prepared by different spin coating deposition process

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

Rahman, Rohanieza Abdul, E-mail: rohanieza.abdrahman@gmail.com; Zulkefle, Muhammad Al Hadi, E-mail: alhadizulkefle@gmail.com; Abdullah, Wan Fazlida Hanim, E-mail: wanfaz@salam.uitm.edu.my

In this study, titanium dioxide (TiO{sub 2}) and zinc oxide (ZnO) bilayer film for pH sensing application will be presented. TiO{sub 2}/ZnO bilayer film with different speed of spin-coating process was deposited on Indium Tin Oxide (ITO), prepared by sol-gel method. This fabricated bilayer film was used as sensing membrane for Extended Gate Field-Effect Transistor (EGFET) for pH sensing application. Experimental results indicated that the sensor is able to detect the sensitivity towards pH buffer solution. In order to obtained the result, sensitivity measurement was done by using the EGFET setup equipment with constant-current (100 µA) and constant-voltage (0.3 V)more » biasing interfacing circuit. TiO{sub 2}/ZnO bilayer film which the working electrode, act as the pH-sensitive membrane was connected to a commercial metal-oxide semiconductor FET (MOSFET). This MOSFET then was connected to the interfacing circuit. The sensitivity of the TiO2 thin film towards pH buffer solution was measured by dipping the sensing membrane in pH4, pH7 and pH10 buffer solution. These thin films were characterized by using Field Emission Scanning Electron Microscope (FESEM) to obtain the surface morphology of the composite bilayer films. In addition, I-V measurement was done in order to determine the electrical properties of the bilayer films. According to the result obtained in this experiment, bilayer film that spin at 4000 rpm, gave highest sensitivity which is 52.1 mV/pH. Relating the I-V characteristic of the thin films and sensitivity, the sensing membrane with higher conductivity gave better sensitivity.« less

Algebra Word Problem Solving Approaches in a Chemistry Context: Equation Worked Examples versus Text Editing

ERIC Educational Resources Information Center

Ngu, Bing Hiong; Yeung, Alexander Seeshing

2013-01-01

Text editing directs students' attention to the problem structure as they classify whether the texts of word problems contain sufficient, missing or irrelevant information for working out a solution. Equation worked examples emphasize the formation of a coherent problem structure to generate a solution. Its focus is on the construction of three…

Progression in High School Students' (Aged 16-18) Conceptualizations about Chemical Reactions in Solution.

ERIC Educational Resources Information Center

Boo, Hong-Kwen; Watson, J. R.

2001-01-01

Explores the development over time of students' understandings of the concept of chemical reaction in the context of two familiar reactions in solution. Based on interviews (n=48), results show that students made some progress in their understanding of the concept of chemical reaction but some fundamental misconceptions remained. (Author/MM)

Pre-Service Chemistry Teachers' Competencies in the Laboratory: A Cross-Grade Study in Solution Preparation

ERIC Educational Resources Information Center

Karatas, F. O.

2016-01-01

One of the prerequisites for chemistry teacher candidates is to demonstrate certain laboratory skills. This article aims to determine and discuss the competencies of pre-service chemistry teachers in a chemistry laboratory context working with solution chemistry content. The participants in this study consisted of a group of pre-service chemistry…

Mathematics for the Workplace. Applications from Insurance. A Teacher's Guide.

ERIC Educational Resources Information Center

Wallace, Johnny M.; Spelts, Charlene E.

This module presents a real-world context in which mathematics skills are used as part of a daily routine. The context is the insurance field, and the module aims to help students see the significance of following through various processes in trying to obtain a solution. Materials in the module, most of which are designed for the teacher to…

Vocabulary Notebook: A Digital Solution to General and Specific Vocabulary Learning Problems in a CLIL Context

ERIC Educational Resources Information Center

Bazo, Plácido; Rodríguez, Romén; Fumero, Dácil

2016-01-01

In this paper, we will introduce an innovative software platform that can be especially useful in a Content and Language Integrated Learning (CLIL) context. This tool is called Vocabulary Notebook, and has been developed to solve all the problems that traditional (paper) vocabulary notebooks have. This tool keeps focus on the personalisation of…

Codimension-2 Brane Black Holes

NASA Astrophysics Data System (ADS)

Zamorano, Nelson; Arias, Cesar; Ordenes, Ariel; Guzman, Francisco

2012-03-01

We analyze the geometry associated to a six dimensional solution of the Einstein's equations. It describes a Schwarzschild de-Sitter black hole on a 3-brane, surrounded by a two dimensional compact bulk. A four dimensional effective cosmological constant and a Planck mass are matched to their six dimensional counterpart. Deviation from Newton's law are computed in both of the solutions found. To learn about the geometry of the bulk, we study the geodesics in this sector. At least, in our opinion, there are some features of these solutions that makes worth to pursue this analysis. The singularity associated to the warped bulk is controlled by the mass M of the black hole. It vanishes if we set M=0. In the same context, it makes an interesting problem to study the Gregory-Laflamme instability in this context [1]. Another feature is the rugby ball type of geometry exhibited by these solutions [2]. They end up in two conical singularities at its respective poles. The branes are located precisely at the poles. Besides, a Wick's rotation generates a connection between different solutions. [4pt] [1] R. Gregory and R. Laflamme, Phys. Rev Lett., 70,2837 (1993)[0pt] [2] S. M. Carroll and M. M. Guica, arXiv:hep-th/0302067

Surface-enhanced Raman spectroscopy of the anti-cancer drug irinotecan in presence of human serum albumin.

PubMed

Vicario, A; Sergo, V; Toffoli, G; Bonifacio, A

2015-03-01

The development of nanotechnological devices and their clinical application in medicine has become increasingly important, especially in the context of targeted and personalized therapy. This is particularly important in cancer therapy, where antitumor drugs are highly cytotoxic and often exert their therapeutic effect at concentrations close to systemic toxicity. In the last years a growing number of studies has started to report the use of plasmonic nanoprobes in the field of theranostics, broadening the application of vibrational spectroscopies like Raman scattering and surface enhanced Raman scattering (SERS) in biomedicine. The present work aims to identify and characterize the vibrational profiles of a widely used anticancer drug, irinotecan (CPT-11). With a rational approach, SERS experiments have been performed on this analyte employing both Au and Ag colloids, starting from simple aqueous solutions up to albumin mixtures. A major step forward for drug detection in albumin solutions has been taken with the adoption of a simple deproteinization strategy, and a two-in-one-step separation and identification by coupling thin layer chromatography, TLC, with SERS (TLC-SERS). The latter has revealed to be a valid system for protein separation and simultaneous analyte detection, showing a potential to become an innovative, sensitive and low cost method for antineoplastic drug profiling in patients' body fluids. Copyright © 2015 Elsevier B.V. All rights reserved.

Employment of Gibbs-Donnan-based concepts for interpretation of the properties of linear polyelectrolyte solutions

USGS Publications Warehouse

Marinsky, J.A.; Reddy, M.M.

1991-01-01

Earlier research has shown that the acid dissociation and metal ion complexation equilibria of linear, weak-acid polyelectrolytes and their cross-linked gel analogues are similarly sensitive to the counterion concentration levels of their solutions. Gibbs-Donnan-based concepts, applicable to the gel, are equally applicable to the linear polyelectrolyte for the accommodation of this sensitivity to ionic strength. This result is presumed to indicate that the linear polyelectrolyte in solution develops counterion-concentrating regions that closely resemble the gel phase of their analogues. Advantage has been taken of this description of linear polyelectrolytes to estimate the solvent uptake by these regions. ?? 1991 American Chemical Society.

Psychobiological Influences on Maternal Sensitivity in the Context of Adversity

ERIC Educational Resources Information Center

Finegood, Eric D.; Blair, Clancy; Granger, Douglas A.; Hibel, Leah C.; Mills-Koonce, Roger

2016-01-01

This study evaluated prospective longitudinal relations among an index of poverty-related cumulative risk, maternal salivary cortisol, child negative affect, and maternal sensitivity across the first 2 postpartum years. Participants included 1,180 biological mothers residing in rural and predominantly low-income communities in the United States.…

Practitioners' Perspectives on Cultural Sensitivity in Latina/o Teen Pregnancy Prevention

ERIC Educational Resources Information Center

Wilkinson-Lee, Ada M.; Russell, Stephen T.; Lee, Faye C. H.

2006-01-01

This study examined practitioners' understandings of cultural sensitivity in the context of pregnancy prevention programs for Latina teens. Fifty-eight practitioners from teen pregnancy prevention programs in California were interviewed in a guided conversation format. Three themes emerged in our analysis. First, practitioners' definitions of…

Experience, Context, and the Visual Perception of Human Movement

ERIC Educational Resources Information Center

Jacobs, Alissa; Pinto, Jeannine; Shiffrar, Maggie

2004-01-01

Why are human observers particularly sensitive to human movement? Seven experiments examined the roles of visual experience and motor processes in human movement perception by comparing visual sensitivities to point-light displays of familiar, unusual, and impossible gaits across gait-speed and identity discrimination tasks. In both tasks, visual…

Cultural context in medical ethics: lessons from Japan.

PubMed

Powell, Tia

2006-04-03

This paper examines two topics in Japanese medical ethics: non-disclosure of medical information by Japanese physicians, and the history of human rights abuses by Japanese physicians during World War II. These contrasting issues show how culture shapes our view of ethically appropriate behavior in medicine. An understanding of cultural context reveals that certain practices, such as withholding diagnostic information from patients, may represent ethical behavior in that context. In contrast, nonconsensual human experimentation designed to harm the patient is inherently unethical irrespective of cultural context. Attempts to define moral consensus in bioethics, and to distinguish between acceptable and unacceptable variation across different cultural contexts, remain central challenges in articulating international, culturally sensitive norms in medical ethics.

Cultural context in medical ethics: lessons from Japan

PubMed Central

Powell, Tia

2006-01-01

This paper examines two topics in Japanese medical ethics: non-disclosure of medical information by Japanese physicians, and the history of human rights abuses by Japanese physicians during World War II. These contrasting issues show how culture shapes our view of ethically appropriate behavior in medicine. An understanding of cultural context reveals that certain practices, such as withholding diagnostic information from patients, may represent ethical behavior in that context. In contrast, nonconsensual human experimentation designed to harm the patient is inherently unethical irrespective of cultural context. Attempts to define moral consensus in bioethics, and to distinguish between acceptable and unacceptable variation across different cultural contexts, remain central challenges in articulating international, culturally sensitive norms in medical ethics. PMID:16759415

NMR studies of water dynamics during sol-to-gel transition of poly (N-isopropylacrylamide) in concentrated aqueous solution

USDA-ARS?s Scientific Manuscript database

The thermo-sensitive polymer, poly(N-isopropylacrylamide) (PNIPAM) undergoes a coil-to-globule transition in an aqueous solution as the temperature is raised through the lower critical solution temperature. Thus far, little is known about the dynamical states of the water molecules that contribute ...

Partition of nonionic organic compounds in aquatic systems

USGS Publications Warehouse

Smith, James A.; Witkowski, Patrick J.; Chiou, Cary T.

1988-01-01

In aqueous systems, the distribution of many nonionic organic solutes in soil-sediment, aquatic organisms, and dissolved organic matter can be explained in terms of a partition model. The nonionic organic solute is distributed between water and different organic phases that behave as bulk solvents. Factors such as polarity, composition, and molecular size of the solute and organic phase determine the relative importance of partition to the environmental distribution of the solute. This chapter reviews these factors in the context of a partition model and also examines several environmental applications of the partition model for surface- and ground-water systems.

An Extended Trajectory Mechanics Approach for Calculating the Path of a Pressure Transient: Derivation and Illustration

NASA Astrophysics Data System (ADS)

Vasco, D. W.

2018-04-01

Following an approach used in quantum dynamics, an exponential representation of the hydraulic head transforms the diffusion equation governing pressure propagation into an equivalent set of ordinary differential equations. Using a reservoir simulator to determine one set of dependent variables leaves a reduced set of equations for the path of a pressure transient. Unlike the current approach for computing the path of a transient, based on a high-frequency asymptotic solution, the trajectories resulting from this new formulation are valid for arbitrary spatial variations in aquifer properties. For a medium containing interfaces and layers with sharp boundaries, the trajectory mechanics approach produces paths that are compatible with travel time fields produced by a numerical simulator, while the asymptotic solution produces paths that bend too strongly into high permeability regions. The breakdown of the conventional asymptotic solution, due to the presence of sharp boundaries, has implications for model parameter sensitivity calculations and the solution of the inverse problem. For example, near an abrupt boundary, trajectories based on the asymptotic approach deviate significantly from regions of high sensitivity observed in numerical computations. In contrast, paths based on the new trajectory mechanics approach coincide with regions of maximum sensitivity to permeability changes.

Sensitivity of atmospheric aerosol scavenging to precipitation intensity and frequency in the context of global climate change

NASA Astrophysics Data System (ADS)

Hou, Pei; Wu, Shiliang; McCarty, Jessica L.; Gao, Yang

2018-06-01

Wet deposition driven by precipitation is an important sink for atmospheric aerosols and soluble gases. We investigate the sensitivity of atmospheric aerosol lifetimes to precipitation intensity and frequency in the context of global climate change. Our sensitivity model simulations, through some simplified perturbations to precipitation in the GEOS-Chem model, show that the removal efficiency and hence the atmospheric lifetime of aerosols have significantly higher sensitivities to precipitation frequencies than to precipitation intensities, indicating that the same amount of precipitation may lead to different removal efficiencies of atmospheric aerosols. Combining the long-term trends of precipitation patterns for various regions with the sensitivities of atmospheric aerosol lifetimes to various precipitation characteristics allows us to examine the potential impacts of precipitation changes on atmospheric aerosols. Analyses based on an observational dataset show that precipitation frequencies in some regions have decreased in the past 14 years, which might increase the atmospheric aerosol lifetimes in those regions. Similar analyses based on multiple reanalysis meteorological datasets indicate that the changes of precipitation intensity and frequency over the past 30 years can lead to perturbations in the atmospheric aerosol lifetimes by 10 % or higher at the regional scale.

Rationalizing context-dependent performance of dynamic RNA regulatory devices.

PubMed

Kent, Ross; Halliwell, Samantha; Young, Kate; Swainston, Neil; Dixon, Neil

2018-06-21

The ability of RNA to sense, regulate and store information is an attractive attribute for a variety of functional applications including the development of regulatory control devices for synthetic biology. RNA folding and function is known to be highly context sensitive, which limits the modularity and reuse of RNA regulatory devices to control different heterologous sequences and genes. We explored the cause and effect of sequence context sensitivity for translational ON riboswitches located in the 5' UTR, by constructing and screening a library of N-terminal synonymous codon variants. By altering the N-terminal codon usage we were able to obtain RNA devices with a broad range of functional performance properties (ON, OFF, fold-change). Linear regression and calculated metrics were used to rationalize the major determining features leading to optimal riboswitch performance, and to identify multiple interactions between the explanatory metrics. Finally, partial least squared (PLS) analysis was employed in order to understand the metrics and their respective effect on performance. This PLS model was shown to provide good explanation of our library. This study provides a novel multi-variant analysis framework by which to rationalize the codon context performance of allosteric RNA-devices. The framework will also serve as a platform for future riboswitch context engineering endeavors.

The word class effect in the picture–word interference paradigm

PubMed Central

Janssen, Niels; Melinger, Alissa; Mahon, Bradford Z.; Finkbeiner, Matthew; Caramazza, Alfonso

2010-01-01

The word class effect in the picture–word interference paradigm is a highly influential finding that has provided some of the most compelling support for word class constraints on lexical selection. However, methodological concerns called for a replication of the most convincing of those effects. Experiment 1 was a direct replication of Pechmann and Zerbst (2002; Experiment 4). Participants named pictures of objects in the context of noun and adverb distractors. Naming took place in bare noun and sentence frame contexts. A word class effect emerged in both bare noun and sentence frame naming conditions, suggesting a semantic origin of the effect. In Experiment 2, participants named objects in the context of noun and verb distractors whose word class relationship to the target and imageability were orthogonally manipulated. As before, naming took place in bare noun and sentence frame naming contexts. In both naming contexts, distractor imageability but not word class affected picture naming latencies. These findings confirm the sensitivity of the picture–word interference paradigm to distractor imageability and suggest the paradigm is not sensitive to distractor word class. The results undermine the use of the word class effect in the picture–word interference paradigm as supportive of word class constraints during lexical selection. PMID:19998070

Efficient ensemble system based on the copper binding motif for highly sensitive and selective detection of cyanide ions in 100% aqueous solutions by fluorescent and colorimetric changes.

PubMed

Jung, Kwan Ho; Lee, Keun-Hyeung

2015-09-15

A peptide-based ensemble for the detection of cyanide ions in 100% aqueous solutions was designed on the basis of the copper binding motif. 7-Nitro-2,1,3-benzoxadiazole-labeled tripeptide (NBD-SSH, NBD-SerSerHis) formed the ensemble with Cu(2+), leading to a change in the color of the solution from yellow to orange and a complete decrease of fluorescence emission. The ensemble (NBD-SSH-Cu(2+)) sensitively and selectively detected a low concentration of cyanide ions in 100% aqueous solutions by a colorimetric change as well as a fluorescent change. The addition of cyanide ions instantly removed Cu(2+) from the ensemble (NBD-SSH-Cu(2+)) in 100% aqueous solutions, resulting in a color change of the solution from orange to yellow and a "turn-on" fluorescent response. The detection limits for cyanide ions were lower than the maximum allowable level of cyanide ions in drinking water set by the World Health Organization. The peptide-based ensemble system is expected to be a potential and practical way for the detection of submicromolar concentrations of cyanide ions in 100% aqueous solutions.

Resilience in Utility Technologies

NASA Astrophysics Data System (ADS)

Seaton, Roger

The following sections are included: * Scope of paper * Preamble * Background to the case-study projects * Source projects * Resilience * Case study 1: Electricity generation * Context * Model * Case study 2: Water recycling * Context * Model * Case study 3: Ecotechnology and water treatment * Context * The problem of classification: Finding a classificatory solution * Application of the new taxonomy to water treatment * Concluding comments and questions * Conclusions * Questions and issues * Purposive or Purposeful? * Resilience: Flexibility and adaptivity? * Resilience: With respect of what? * Risk, uncertainty, surprise, emergence - What sort of shock, and who says so? * Co-evolutionary friction * References

Culture and change blindness.

PubMed

Masuda, Takahiko; Nisbett, Richard E

2006-03-04

Research on perception and cognition suggests that whereas East Asians view the world holistically, attending to the entire field and relations among objects, Westerners view the world analytically, focusing on the attributes of salient objects. These propositions were examined in the change-blindness paradigm. Research in that paradigm finds American participants to be more sensitive to changes in focal objects than to changes in the periphery or context. We anticipated that this would be less true for East Asians and that they would be more sensitive to context changes than would Americans. We presented participants with still photos and with animated vignettes having changes in focal object information and contextual information. Compared to Americans, East Asians were more sensitive to contextual changes than to focal object changes. These results suggest that there can be cultural variation in what may seem to be basic perceptual processes. 2006 Lawrence Erlbaum Associates, Inc.

Environmental sensitivity: equivocal illness in the context of place.

PubMed

Fletcher, Christopher M

2006-03-01

This article presents a phenomenologically oriented description of the interaction of illness experience, social context, and place. This is used to explore an outbreak of environmental sensitivities in Nova Scotia, Canada. Environmental Sensitivity (ES) is a popular designation for bodily reactions to mundane environmental stimuli that are insignificant for most people. Mainstream medicine cannot support the popular models of this disease process and consequently illness experience is subject to ambiguity and contestation. As an 'equivocal illness', ES generates considerable social action around the nature, meaning and validity of suffering. Sense of place plays an important role in this process. In this case, the meanings that accrue to illness experience and that produce salient popular disease etiology are grounded in the experience and social construction of the Nova Scotian landscape over time. Shifting representations of place are reflected in illness experience and the meanings that arise around illness are emplaced in landscape.

Vectorial capacity and vector control: reconsidering sensitivity to parameters for malaria elimination

PubMed Central

Brady, Oliver J.; Godfray, H. Charles J.; Tatem, Andrew J.; Gething, Peter W.; Cohen, Justin M.; McKenzie, F. Ellis; Perkins, T. Alex; Reiner, Robert C.; Tusting, Lucy S.; Sinka, Marianne E.; Moyes, Catherine L.; Eckhoff, Philip A.; Scott, Thomas W.; Lindsay, Steven W.; Hay, Simon I.; Smith, David L.

2016-01-01

Background Major gains have been made in reducing malaria transmission in many parts of the world, principally by scaling-up coverage with long-lasting insecticidal nets and indoor residual spraying. Historically, choice of vector control intervention has been largely guided by a parameter sensitivity analysis of George Macdonald's theory of vectorial capacity that suggested prioritizing methods that kill adult mosquitoes. While this advice has been highly successful for transmission suppression, there is a need to revisit these arguments as policymakers in certain areas consider which combinations of interventions are required to eliminate malaria. Methods and Results Using analytical solutions to updated equations for vectorial capacity we build on previous work to show that, while adult killing methods can be highly effective under many circumstances, other vector control methods are frequently required to fill effective coverage gaps. These can arise due to pre-existing or developing mosquito physiological and behavioral refractoriness but also due to additive changes in the relative importance of different vector species for transmission. Furthermore, the optimal combination of interventions will depend on the operational constraints and costs associated with reaching high coverage levels with each intervention. Conclusions Reaching specific policy goals, such as elimination, in defined contexts requires increasingly non-generic advice from modelling. Our results emphasize the importance of measuring baseline epidemiology, intervention coverage, vector ecology and program operational constraints in predicting expected outcomes with different combinations of interventions. PMID:26822603

Sensitivity Analysis and Optimization of Aerodynamic Configurations with Blend Surfaces

NASA Technical Reports Server (NTRS)

Thomas, A. M.; Tiwari, S. N.

1997-01-01

A novel (geometrical) parametrization procedure using solutions to a suitably chosen fourth order partial differential equation is used to define a class of airplane configurations. Inclusive in this definition are surface grids, volume grids, and grid sensitivity. The general airplane configuration has wing, fuselage, vertical tail and horizontal tail. The design variables are incorporated into the boundary conditions, and the solution is expressed as a Fourier series. The fuselage has circular cross section, and the radius is an algebraic function of four design parameters and an independent computational variable. Volume grids are obtained through an application of the Control Point Form method. A graphic interface software is developed which dynamically changes the surface of the airplane configuration with the change in input design variable. The software is made user friendly and is targeted towards the initial conceptual development of any aerodynamic configurations. Grid sensitivity with respect to surface design parameters and aerodynamic sensitivity coefficients based on potential flow is obtained using an Automatic Differentiation precompiler software tool ADIFOR. Aerodynamic shape optimization of the complete aircraft with twenty four design variables is performed. Unstructured and structured volume grids and Euler solutions are obtained with standard software to demonstrate the feasibility of the new surface definition.

Surface acidity and solid-state compatibility of excipients with an acid-sensitive API: case study of atorvastatin calcium.

PubMed

Govindarajan, Ramprakash; Landis, Margaret; Hancock, Bruno; Gatlin, Larry A; Suryanarayanan, Raj; Shalaev, Evgenyi Y

2015-04-01

The objectives of this study were to measure the apparent surface acidity of common excipients and to correlate the acidity with the chemical stability of an acid-sensitive active pharmaceutical ingredient (API) in binary API-excipient powder mixtures. The acidity of 26 solid excipients was determined by two methods, (i) by measuring the pH of their suspensions or solutions and (ii) the pH equivalent (pHeq) measured via ionization of probe molecules deposited on the surface of the excipients. The chemical stability of an API, atorvastatin calcium (AC), in mixtures with the excipients was evaluated by monitoring the appearance of an acid-induced degradant, atorvastatin lactone, under accelerated storage conditions. The extent of lactone formation in AC-excipient mixtures was presented as a function of either solution/suspension pH or pHeq. No lactone formation was observed in mixtures with excipients having pHeq > 6, while the lactone levels were pronounced (> 0.6% after 6 weeks at 50°C/20% RH) with excipients exhibiting pHeq < 3. The three pHeq regions (> 6, 3-6, and < 3) were consistent with the reported solution pH-stability profile of AC. In contrast to the pHeq scale, lactone formation did not show any clear trend when plotted as a function of the suspension/solution pH. Two mechanisms to explain the discrepancy between the suspension/solution pH and the chemical stability data were discussed. Acidic excipients, which are expected to be incompatible with an acid-sensitive API, were identified based on pHeq measurements. The incompatibility prediction was confirmed in the chemical stability tests using AC as an example of an acid-sensitive API.

Improving sensitivity of gold nanoparticle based fluorescence quenching and colorimetric aptasensor by using water resuspended gold nanoparticle.

PubMed

Liu, Jinchuan; Guan, Zheng; Lv, Zhenzhen; Jiang, Xiaoling; Yang, Shuming; Chen, Ailiang

2014-02-15

Gold nanoparticles (AuNPs) based fluorescence quenching or colorimetric aptasensor have been developed for many analytes recently largely because of the ease of detection, high sensitivity, and potential for high-throughput analysis. However, the effects of remnant non-AuNPs components in the colloid gold solution on these assays performance remain unclear. For the first time, we demonstrated that the remnant sodium citrate and the reaction products of three acids play counteractive roles in AuNPs based fluorescence quenching and colorimetric aptasensor in three ways in this study. First, the remnant sodium citrate in the colloid gold solution could increase the fluorescence intensity of FAM labeled on the aptamer that reduce the efficiency of AuNPs fluorescent quenching. Second, the reaction products of citric acid, HCl and ketoglutaric acid reduce the fluorescence recovery by quenching the fluorescence of FAM labeled on the aptamer dissociated from the surface of AuNPs upon addition of target. Lastly, the reaction products of three acids reduce the pH value of the colloid gold solution that reduce the sensitivity of AuNPs based colorimetric aptasensor by increasing the adsorption of aptamer to surface of AuNPs. With sulfadimethoxine and thrombin as model analytes, we found that water resuspended AuNPs can significantly increase the sensitivity by more than 10-fold for AuNPs based fluorescence quenching aptasensor. In the AuNPs based colorimetric aptasensor for sulfadimethoxine using the water resuspended AuNPs, the sensitivity also was increased by 10-fold compared with that of original AuNPs. The findings in this study provide theoretical guidance for further improving AuNPs based fluorescent quenching and colorimetric aptasensor by adjusting the composition of AuNPs solution. © 2013 Elsevier B.V. All rights reserved.

A Move Towards Postmethod Pedagogy in the Iranian EFL Context: Panacea or More Pain?

ERIC Educational Resources Information Center

Safari, Parvin; Rashidi, Nasser

2015-01-01

Kumaravadivelu's (2003) introduction and development of "postmethod" led to the demise of methods and a dramatic change in the language teaching profession. In fact, it can be claimed that the arrival of postmethod pedagogy in language teaching might be the reason for the abandonment and replacement of method by context sensitive,…

Ethnography as Method, Methodology, and "Deep Theorizing" Closing the Gap between Text and Context in Academic Writing Research

ERIC Educational Resources Information Center

Lillis, Theresa

2008-01-01

This article critically explores the value of ethnography for enhancing context-sensitive approaches to the study of academic writing. Drawing on data from two longitudinal studies, student writing in the United Kingdom and professional academic writing in Hungary, Slovakia, Spain, and Portugal, the author illustrates the different contributions…

Monitoring of oxidation steps of ascorbic acid redox reaction by kinetics-sensitive voltcoulometry in unsupported and supported aqueous solutions and real samples.

PubMed

Orlický, Jozef; Gmucová, Katarína; Thurzo, Ilja; Pavlásek, Juraj

2003-04-01

Aqueous solutions of ascorbic acid in unsupported and supported aqueous solutions and real samples were studied by the kinetics-sensitive double-step voltcoulommetric method with the aim to contribute to a better understanding of its behavior in biological systems. The data obtained from measurements made on analytes prepared in the laboratory, as well as those made on real samples (some commercial orange drinks, flash of the fresh fruits) point to the redox reaction of L-ascorbic acid (L-AH2) being very sensitive to both the presence of dissolved gaseous species (O2, CO2) and the ionic strenght in the analyte. Either the dissolved gaseous species, or the higher ionic strength caused by both the presence of supporting electrolyte and increased total concentration of ascorbic acid, respectively, give birth to the degradation of L-AH2. Naturally, the highest percentage of L-AH2 was spotted in fresh fruit.

Liquid ``Coffee Rings'' and the Spreading of Volatile Liquid Mixtures

NASA Astrophysics Data System (ADS)

Wood, Clay; Pye, Justin; Burton, Justin

When a volatile liquid drop is placed on a wetting surface, it rapidly spreads and evaporates. The spreading dynamics and drop geometry are determined by a balance between thermal and interfacial forces, including Marangoni effects. However, this spreading behavior is drastically altered when drops contain a miniscule amount of a less-volatile miscible liquid (solute) in the bulk (solvent); contact line instabilities in the form of ``fingers'' develop. Characteristic finger size increases with increasing solute concentration and is apparent for concentrations as small as 0.1% by volume. Also, the spreading rate depends sensitively on the solute concentration, especially if the solute preferentially wets the substrate. At higher solute concentrations, the spreading droplet will form ``beads'' at the contact line, rather than fingers, and are deposited as the solvent recedes and evaporates, leaving behind a complex pattern of solute micro-droplets. Liquid ``coffee rings'' are often left behind after evaporation because there is a high evaporation rate of the solvent at the contact line, which increases the concentration of the solute, and the longevity of the rings depends on the solute vapor pressure. These results highlight the unusual sensitivity to contamination of volatile spreading, and the complex patterns of liquid contamination deposited following evaporation from a wetted surface. NSF 1455086.

Constraint-based integration of planning and scheduling for space-based observatory management

NASA Technical Reports Server (NTRS)

Muscettola, Nicola; Smith, Steven F.

1994-01-01

Progress toward the development of effective, practical solutions to space-based observatory scheduling problems within the HSTS scheduling framework is reported. HSTS was developed and originally applied in the context of the Hubble Space Telescope (HST) short-term observation scheduling problem. The work was motivated by the limitations of the current solution and, more generally, by the insufficiency of classical planning and scheduling approaches in this problem context. HSTS has subsequently been used to develop improved heuristic solution techniques in related scheduling domains and is currently being applied to develop a scheduling tool for the upcoming Submillimeter Wave Astronomy Satellite (SWAS) mission. The salient architectural characteristics of HSTS and their relationship to previous scheduling and AI planning research are summarized. Then, some key problem decomposition techniques underlying the integrated planning and scheduling approach to the HST problem are described; research results indicate that these techniques provide leverage in solving space-based observatory scheduling problems. Finally, more recently developed constraint-posting scheduling procedures and the current SWAS application focus are summarized.

A wireless trust model for healthcare.

PubMed

Wickramasinghe, Nilmini; Misra, Santosh K

2004-01-01

In today's context of escalating costs, managed care, regulations such as the Health Insurance Portability and Accountability Act (HIPAA) and a technology savvy patient, the healthcare industry can no longer be complacent regarding embracing technologies to enable better, more effective and efficient practice management. In such an environment, many healthcare organisations are turning to m-commerce or wireless solutions. These solutions, in particular the mobile electronic patient record, have many advantages over their wired counterparts, including significant cost advantages, higher levels of physician acceptance, more functionalities as well as enabling easy accessibility to healthcare in remote geographic regions, however, they also bring with them challenges of their own. One such major challenge is security. To date, few models exist that help establish an appropriate framework, in the context of wireless in healthcare, in which to understand and evaluate all the security issues let alone facilitate the development of systematic and robust solutions. Our paper addresses this need by outlining an appropriate mobile trust model for such a scenario in healthcare organisations.

Considering context in quality improvement interventions and implementation: concepts, frameworks, and application.

PubMed

McDonald, Kathryn M

2013-01-01

Growing consensus within the health care field suggests that context matters and needs more concerted study for helping those who implement and conduct research on quality improvement interventions. Health care delivery system decision makers require information about whether an intervention tested in one context will work in another with some differences from the original site. We aimed to define key terms, enumerate candidate domains for the study of context, provide examples from the pediatric quality improvement literature, and identify potential measures for selected contexts. Key sources include the organizational literature, broad evaluation frameworks, and a recent project in the patient safety area on context sensitivity. The article concludes with limitations and next steps for developments in this area. Copyright © 2013 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

Sustainable sewage management and the inertia to change

NASA Astrophysics Data System (ADS)

Öberg, G.

2012-12-01

Increasing economic costs and environmental concerns have led to that planners around the world are progressively questioning the prevailing sewage management paradigm, calling for a shift in the hydrosocial contract to embrace more sustainable solutions, to be based on closed-loops rather than linear end-of-pipe solutions. Despite considerable attention to the technical possibilities for delivering sewage services in a more integrated and sustainable fashion, shifts in planning and management have been slow. Based on an extensive study of Australian cities, Brown et al (2009) have developed a model with six transitional stages and argue that "while there may be cognitive changes (best practice thinking such as water sustainable urban design), there has not been sufficient normative and regulative change to support new practice." They contrast three historic transition stages with three successive sustainable stages. Unfortunately, the study ends in a rather vague outline of "the Water Sensitive City", with little sign-posts indicating how one might transition to this seemingly utopian last stage. In the present paper, we discuss the normative tensions created between the different actors in this increasingly complex playing field, who represent different and often competing values. We suggest that cities have difficulties transitioning from the old contract to one of the newer ones because the hydro-social contract promised by these new stages create normative tensions not only between the new and the old, but also between what one might call different types of environmentalists: naturalists and pragmatists. The naturalists, who for example are very voiced in several cities along the North American west coast, tend to embrace the perception of Nature described by environmental historians as Untouched Wilderness, where technology is pinpointed as the root of the problems. In contrast, the other side lean more on the idea of modernity, with a more pragmatic approach to nature, which first and foremost is seen as a provider of material resources and technology is a tool that aids solving the problem with the limited supply. The naturalists' cognitive response points to solutions that are perceived as 'natural' such as composting and constructed wetlands, but do to not easily embrace solutions that are perceived as 'technical', such as smart metering, biogas reactors, and recovery of pelleted phosphorous compounds. We suggest that transition to the 'Water Sensitive City' requires explicit recognition that sewage management is a context-dependent multi-dimensional, multi-objective challenge in which competing objectives must be identified and trade-offs made, which includes recognizing and finding ways to manage the tacit tensions caused by competing normative underpinnings among different types of environmentalism.

21 CFR 524.1044b - Gentamicin sulfate, betamethasone valerate otic solution.

Code of Federal Regulations, 2011 CFR

2011-04-01

... use—(i) For the treatment of acute and chronic otitis externa caused by bacteria sensitive to.... (ii) For the treatment of infected superficial lesions caused by bacteria sensitive to gentamicin in...

21 CFR 524.1044b - Gentamicin sulfate, betamethasone valerate otic solution.

Code of Federal Regulations, 2010 CFR

2010-04-01

... use—(i) For the treatment of acute and chronic otitis externa caused by bacteria sensitive to.... (ii) For the treatment of infected superficial lesions caused by bacteria sensitive to gentamicin in...

21 CFR 524.1044b - Gentamicin and betamethasone otic solution.

Code of Federal Regulations, 2014 CFR

2014-04-01

... treatment of acute and chronic otitis externa caused by bacteria sensitive to gentamicin in dogs, instill... of infected superficial lesions caused by bacteria sensitive to gentamicin in dogs and cats, apply a...

Role of Co-Sensitizers in Dye-Sensitized Solar Cells.

PubMed

Krishna, Narra Vamsi; Krishna, Jonnadula Venkata Suman; Mrinalini, Madoori; Prasanthkumar, Seelam; Giribabu, Lingamallu

2017-12-08

Co-sensitization is a popular route towards improved efficiency and stability of dye-sensitized solar cells (DSSCs). In this context, the power conversion efficiency (PCE) values of DSSCs incorporating Ru- and porphyrin-based dyes can be improved from 8-11 % to 11-14 % after the addition of additives, co-adsorbents, and co-sensitizers that reduce aggregation and charge recombination in the device. Among the three supporting material types, co-sensitizers play a major role to enhance the performance and stability of DSSCs, which is requried for commercialization. In this Minireview, we highlight the role co-sensitizers play in improving photovoltaic performance of devices containing Ru- and porphyrin-based sensitizers. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Contextual modulation of attention in human category learning.

PubMed

George, David N; Kruschke, John K

2012-12-01

In a category-learning experiment, we assessed whether participants were able to selectively attend to different components of a compound stimulus in two distinct contexts. The participants were presented with stimulus compounds for which they had to learn categorical labels. Each compound comprised one feature from each of two dimensions, and on different trials the compound was presented in two contexts, X and Y. In Context X, Dimension A was relevant to the solution of the categorization task and Dimension B was irrelevant, whereas in Context Y, Dimension A was irrelevant and Dimension B was relevant. The results of transfer tests to novel stimuli suggested that people learned to attend selectively to Dimension A in Context X and Dimension B in Context Y. These findings contribute to the growing body of evidence that people can learn to selectively attend to particular dimensions of stimuli dependent on the context in which the stimuli are presented. Furthermore, the findings demonstrate that context-dependent changes in attention transfer to other categorization tasks involving novel stimuli.

Electrodialytic in-line preconcentration for ionic solute analysis.

PubMed

Ohira, Shin-Ichi; Yamasaki, Takayuki; Koda, Takumi; Kodama, Yuko; Toda, Kei

2018-04-01

Preconcentration is an effective way to improve analytical sensitivity. Many types of methods are used for enrichment of ionic solute analytes. However, current methods are batchwise and include procedures such as trapping and elution. In this manuscript, we propose in-line electrodialytic enrichment of ionic solutes. The method can enrich ionic solutes within seconds by quantitative transfer of analytes from the sample solution to the acceptor solution under an electric field. Because of quantitative ion transfer, the enrichment factor (the ratio of the concentration in the sample and to that in the obtained acceptor solution) only depends on the flow rate ratio of the sample solution to the acceptor solution. The ratios of the concentrations and flow rates are equal for ratios up to 70, 20, and 70 for the tested ionic solutes of inorganic cations, inorganic anions, and heavy metal ions, respectively. The sensitivity of ionic solute determinations is also improved based on the enrichment factor. The method can also simultaneously achieve matrix isolation and enrichment. The method was successively applied to determine the concentrations of trace amounts of chloroacetic acids in tap water. The regulated concentration levels cannot be determined by conventional high-performance liquid chromatography with ultraviolet detection (HPLC-UV) without enrichment. However, enrichment with the present method is effective for determination of tap water quality by improving the limits of detection of HPLC-UV. The standard addition test with real tap water samples shows good recoveries (94.9-109.6%). Copyright © 2017 Elsevier B.V. All rights reserved.

Analytic regularization of uniform cubic B-spline deformation fields.

PubMed

Shackleford, James A; Yang, Qi; Lourenço, Ana M; Shusharina, Nadya; Kandasamy, Nagarajan; Sharp, Gregory C

2012-01-01

Image registration is inherently ill-posed, and lacks a unique solution. In the context of medical applications, it is desirable to avoid solutions that describe physically unsound deformations within the patient anatomy. Among the accepted methods of regularizing non-rigid image registration to provide solutions applicable to medical practice is the penalty of thin-plate bending energy. In this paper, we develop an exact, analytic method for computing the bending energy of a three-dimensional B-spline deformation field as a quadratic matrix operation on the spline coefficient values. Results presented on ten thoracic case studies indicate the analytic solution is between 61-1371x faster than a numerical central differencing solution.

"Students Get Bogged Down": How Religious Israeli Elementary Teachers View Problems and Solutions in Bible Teaching

ERIC Educational Resources Information Center

Walfish, Ruth A.; Brody, David L.

2018-01-01

Bible teachers in contemporary society confront serious problems related to the nature of the biblical text and the socio-cultural context of their teaching. This study, based on semi-structured interviews, examines the problems that five expert religious Israeli elementary school teachers encounter in their teaching and the solutions they employ.…

The Dilemma and Solutions for the Conflicts between Equality and Excellence in the Massification of Higher Education in Taiwan

ERIC Educational Resources Information Center

Hsiou-Huai, Wang

2012-01-01

Equality and excellence are two core values underlying many educational endeavors; however, they are often in conflict and controversy. This article intends to examine the dilemma created by such controversies in the context of massification of higher education in Taiwan and attempt to provide solutions from both the theoretical and policy…

Exploring Insight: Focus on Shifts of Attention

ERIC Educational Resources Information Center

Palatnik, Alik; Koichu, Boris

2015-01-01

The paper presents and analyses a sequence of events that preceded an insight solution to a challenging problem in the context of numerical sequences. A three­week long solution process by a pair of ninth­-grade students is analysed by means of the theory of shifts of attention. The goal for this article is to reveal the potential of this theory…

Exploration and validation of clusters of physically abused children.

PubMed

Sabourin Ward, Caryn; Haskett, Mary E

2008-05-01

Cluster analysis was used to enhance understanding of heterogeneity in social adjustment of physically abused children. Ninety-eight physically abused children (ages 5-10) were clustered on the basis of social adjustment, as measured by observed behavior with peers on the school playground and by teacher reports of social behavior. Seventy-seven matched nonabused children served as a comparison sample. Clusters were validated on the basis of observed parental sensitivity, parents' self-reported disciplinary tactics, and children's social information processing operations (i.e., generation of solutions to peer relationship problems and attributions of peer intentions in social situations). Three subgroups of physically abused children emerged from the cluster analysis; clusters were labeled Socially Well Adjusted, Hanging in There, and Social Difficulties. Examination of cluster differences on risk and protective factors provided substantial evidence in support of the external validity of the three-cluster solution. Specifically, clusters differed significantly in attributions of peer intent and in parenting (i.e., sensitivity and harshness of parenting). Clusters also differed in the ways in which they were similar to, or different from, the comparison group of nonabused children. Results supported the contention that there were clinically relevant subgroups of physically abused children with potentially unique treatment needs. Findings also pointed to the relevance of social information processing operations and parenting context in understanding diversity among physically abused children. Pending replication, findings provide support for the importance of considering unique treatment of needs among physically abused children. A singular approach to intervention is unlikely to be effective for these children. For example, some physically abused children might need a more intensive focus on development of prosocial skills in relationships with peers while the prosocial skills of other abused children will be developmentally appropriate. In contrast, most physically abused children might benefit from training in social problem-solving skills. Findings also point to the importance of promoting positive parenting practices in addition to reducing harsh discipline of physically abusive parents.

Phased Array Imaging of Complex-Geometry Composite Components.

PubMed

Brath, Alex J; Simonetti, Francesco

2017-10-01

Progress in computational fluid dynamics and the availability of new composite materials are driving major advances in the design of aerospace engine components which now have highly complex geometries optimized to maximize system performance. However, shape complexity poses significant challenges to traditional nondestructive evaluation methods whose sensitivity and selectivity rapidly decrease as surface curvature increases. In addition, new aerospace materials typically exhibit an intricate microstructure that further complicates the inspection. In this context, an attractive solution is offered by combining ultrasonic phased array (PA) technology with immersion testing. Here, the water column formed between the complex surface of the component and the flat face of a linear or matrix array probe ensures ideal acoustic coupling between the array and the component as the probe is continuously scanned to form a volumetric rendering of the part. While the immersion configuration is desirable for practical testing, the interpretation of the measured ultrasonic signals for image formation is complicated by reflection and refraction effects that occur at the water-component interface. To account for refraction, the geometry of the interface must first be reconstructed from the reflected signals and subsequently used to compute suitable delay laws to focus inside the component. These calculations are based on ray theory and can be computationally intensive. Moreover, strong reflections from the interface can lead to a thick dead zone beneath the surface of the component which limits sensitivity to shallow subsurface defects. This paper presents a general approach that combines advanced computing for rapid ray tracing in anisotropic media with a 256-channel parallel array architecture. The full-volume inspection of complex-shape components is enabled through the combination of both reflected and transmitted signals through the part using a pair of arrays held in a yoke configuration. Experimental results are provided for specimens of increasing complexity relevant to aerospace applications such as fan blades. It is shown that PA technology can provide a robust solution to detect a variety of defects including porosity and waviness in composite parts.

A Novel Tri-Enzyme System in Combination with Laser-Driven NMR Enables Efficient Nuclear Polarization of Biomolecules in Solution

PubMed Central

Lee, Jung Ho; Cavagnero, Silvia

2013-01-01

NMR is an extremely powerful, yet insensitive technique. Many available nuclear polarization methods that address sensitivity are not directly applicable to low-concentration biomolecules in liquids and are often too invasive. Photochemically induced dynamic nuclear polarization (photo-CIDNP) is no exception. It needs high-power laser irradiation, which often leads to sample degradation, and photosensitizer reduction. Here, we introduce a novel tri-enzyme system that significantly overcomes the above challenges rendering photo-CIDNP a practically applicable technique for NMR sensitivity enhancement in solution. The specificity of the nitrate reductase (NR) enzyme is exploited to selectively in situ re-oxidize the reduced photo-CIDNP dye FMNH2. At the same time, the oxygen-scavenging ability of glucose oxidase (GO) and catalase (CAT) is synergistically employed to prevent sample photodegradation. The resulting tri-enzyme system (NR-GO-CAT) enables prolonged sensitivity-enhanced data collection in 1D and 2D heteronuclear NMR, leading to the highest photo-CIDNP sensitivity enhancement (48-fold relative to SE-HSQC) achieved to date for amino acids and polypeptides in solution. NR-GO-CAT extends the concentration limit of photo-CIDNP NMR down to the low micromolar range. In addition, sensitivity (relative to the reference SE-HSQC) is found to be inversely proportional to sample concentration, paving the way to the future analysis of even more diluted samples. PMID:23560683

Designing Metallic and Insulating Nanocrystal Heterostructures to Fabricate Highly Sensitive and Solution Processed Strain Gauges for Wearable Sensors.

PubMed

Lee, Woo Seok; Lee, Seung-Wook; Joh, Hyungmok; Seong, Mingi; Kim, Haneun; Kang, Min Su; Cho, Ki-Hyun; Sung, Yun-Mo; Oh, Soong Ju

2017-12-01

All-solution processed, high-performance wearable strain sensors are demonstrated using heterostructure nanocrystal (NC) solids. By incorporating insulating artificial atoms of CdSe quantum dot NCs into metallic artificial atoms of Au NC thin film matrix, metal-insulator heterostructures are designed. This hybrid structure results in a shift close to the percolation threshold, modifying the charge transport mechanism and enhancing sensitivity in accordance with the site percolation theory. The number of electrical pathways is also manipulated by creating nanocracks to further increase its sensitivity, inspired from the bond percolation theory. The combination of the two strategies achieves gauge factor up to 5045, the highest sensitivity recorded among NC-based strain gauges. These strain sensors show high reliability, durability, frequency stability, and negligible hysteresis. The fundamental charge transport behavior of these NC solids is investigated and the combined site and bond percolation theory is developed to illuminate the origin of their enhanced sensitivity. Finally, all NC-based and solution-processed strain gauge sensor arrays are fabricated, which effectively measure the motion of each finger joint, the pulse of heart rate, and the movement of vocal cords of human. This work provides a pathway for designing low-cost and high-performance electronic skin or wearable devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

All-fiber intensity bend sensor based on photonic crystal fiber with asymmetric air-hole structure

NASA Astrophysics Data System (ADS)

Budnicki, Dawid; Szostkiewicz, Lukasz; Szymanski, Michal O.; Ostrowski, Lukasz; Holdynski, Zbigniew; Lipinski, Stanislaw; Murawski, Michal; Wojcik, Grzegorz; Makara, Mariusz; Poturaj, Krzysztof; Mergo, Pawel; Napierala, Marek; Nasilowski, Tomasz

2017-10-01

Monitoring the geometry of an moving element is a crucial task for example in robotics. The robots equipped with fiber bend sensor integrated in their arms can be a promising solution for medicine, physiotherapy and also for application in computer games. We report an all-fiber intensity bend sensor, which is based on microstructured multicore optical fiber. It allows to perform a measurement of the bending radius as well as the bending orientation. The reported solution has a special airhole structure which makes the sensor only bend-sensitive. Our solution is an intensity based sensor, which measures power transmitted along the fiber, influenced by bend. The sensor is based on a multicore fiber with the special air-hole structure that allows detection of bending orientation in range of 360°. Each core in the multicore fiber is sensitive to bend in specified direction. The principle behind sensor operation is to differentiate the confinement loss of fundamental mode propagating in each core. Thanks to received power differences one can distinguish not only bend direction but also its amplitude. Multicore fiber is designed to utilize most common light sources that operate at 1.55 μm thus ensuring high stability of operation. The sensitivity of the proposed solution is equal 29,4 dB/cm and the accuracy of bend direction for the fiber end point is up to 5 degrees for 15 cm fiber length. Such sensitivity allows to perform end point detection with millimeter precision.

Early life stress in rats sex-dependently affects remote endocrine rather than behavioral consequences of adult exposure to contextual fear conditioning.

PubMed

Fuentes, Sílvia; Daviu, Núria; Gagliano, Humberto; Belda, Xavier; Armario, Antonio; Nadal, Roser

2018-05-30

Exposure to electric foot-shocks can induce in rodents contextual fear conditioning, generalization of fear to other contexts and sensitization of the hypothalamic-pituitary-adrenal (HPA) axis to further stressors. All these aspects are relevant for the study of post-traumatic stress disorder. In the present work we evaluated in rats the sex differences and the role of early life stress (ELS) in fear memories, generalization and sensitization. During the first postnatal days subjects were exposed to restriction of nesting material along with exposure to a "substitute" mother. In the adulthood they were exposed to (i) a contextual fear conditioning to evaluate long-term memory and extinction and (ii) to a novel environment to study cognitive fear generalization and HPA axis heterotypic sensitization. ELS did not alter acquisition, expression or extinction of context fear conditioned behavior (freezing) in either sex, but reduced activity in novel environments only in males. Fear conditioning associated hypoactivity in novel environments (cognitive generalization) was greater in males than females but was not specifically affected by ELS. Although overall females showed greater basal and stress-induced levels of ACTH and corticosterone, an interaction between ELS, shock exposure and sex was found regarding HPA hormones. In males, ELS did not affect ACTH response in any situation, whereas in females, ELS reduced both shock-induced sensitization of ACTH and its conditioned response to the shock context. Also, shock-induced sensitization of corticosterone was only observed in males and ELS specifically reduced corticosterone response to stressors in males but not females. In conclusion, ELS seems to have only a minor impact on shock-induced behavioral conditioning, while affecting the unconditioned and conditioned responses of HPA hormones in a sex-dependent manner. Copyright © 2018. Published by Elsevier Inc.

Sensitivity and specificity of General Movements Assessment for diagnostic accuracy of detecting cerebral palsy early in an Australian context.

PubMed

Morgan, Catherine; Crowle, Cathryn; Goyen, Traci-Anne; Hardman, Caroline; Jackman, Michelle; Novak, Iona; Badawi, Nadia

2016-01-01

The aim of this study was to calculate the sensitivity and specificity of the General Movements Assessment (GMA) for estimating diagnostic accuracy in detecting cerebral palsy (CP) in an Australian context by a newly established NSW rater network. A prospective longitudinal cross-sectional study was conducted. The GMA was blind-rated from conventional video by two independent certified raters, blinded to medical history. A third rater resolved disagreements. High-risk population screening for CP using the GMA during the fidgety period (12-20 weeks) was carried out in four neonatal intensive care units and one CP service over a 30-month period (2012-2013). Participants were 259 high-risk infants. Sensitivity and specificity values were calculated with true positives defined as a confirmed diagnosis of CP from a medical doctor. Of the 259 infants assessed, 1-year follow-up data were available for 187. Of these, n = 48 had absent fidgety (high risk for CP), n = 138 had normal fidgety (low risk for CP), and n = 1 had abnormal fidgety (high risk for a neurological disorder). Of the 48 with absent fidgety movements, 39 had received a diagnosis of CP by 18 months and another 6 had an abnormal outcome. Of the n = 138 normal fidgety cases, n = 99 cases had a normal outcome, n = 38 had an abnormal outcome but not CP, and n = 1 had CP. For detecting CP, we had a sensitivity of 98% and specificity of 94%. GMA was feasible in an Australian context and accurately identified CP with a sensitivity and specificity comparable with European standards and published neuroimaging data. © 2015 The Authors. Journal of Paediatrics and Child Health © 2015 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

Quantum chemistry in arbitrary dielectric environments: Theory and implementation of nonequilibrium Poisson boundary conditions and application to compute vertical ionization energies at the air/water interface

NASA Astrophysics Data System (ADS)

Coons, Marc P.; Herbert, John M.

2018-06-01

Widely used continuum solvation models for electronic structure calculations, including popular polarizable continuum models (PCMs), usually assume that the continuum environment is isotropic and characterized by a scalar dielectric constant, ɛ. This assumption is invalid at a liquid/vapor interface or any other anisotropic solvation environment. To address such scenarios, we introduce a more general formalism based on solution of Poisson's equation for a spatially varying dielectric function, ɛ(r). Inspired by nonequilibrium versions of PCMs, we develop a similar formalism within the context of Poisson's equation that includes the out-of-equilibrium dielectric response that accompanies a sudden change in the electron density of the solute, such as that which occurs in a vertical ionization process. A multigrid solver for Poisson's equation is developed to accommodate the large spatial grids necessary to discretize the three-dimensional electron density. We apply this methodology to compute vertical ionization energies (VIEs) of various solutes at the air/water interface and compare them to VIEs computed in bulk water, finding only very small differences between the two environments. VIEs computed using approximately two solvation shells of explicit water molecules are in excellent agreement with experiment for F-(aq), Cl-(aq), neat liquid water, and the hydrated electron, although errors for Li+(aq) and Na+(aq) are somewhat larger. Nonequilibrium corrections modify VIEs by up to 1.2 eV, relative to models based only on the static dielectric constant, and are therefore essential to obtain agreement with experiment. Given that the experiments (liquid microjet photoelectron spectroscopy) may be more sensitive to solutes situated at the air/water interface as compared to those in bulk water, our calculations provide some confidence that these experiments can indeed be interpreted as measurements of VIEs in bulk water.

Quantum chemistry in arbitrary dielectric environments: Theory and implementation of nonequilibrium Poisson boundary conditions and application to compute vertical ionization energies at the air/water interface.

PubMed

Coons, Marc P; Herbert, John M

2018-06-14

Widely used continuum solvation models for electronic structure calculations, including popular polarizable continuum models (PCMs), usually assume that the continuum environment is isotropic and characterized by a scalar dielectric constant, ε. This assumption is invalid at a liquid/vapor interface or any other anisotropic solvation environment. To address such scenarios, we introduce a more general formalism based on solution of Poisson's equation for a spatially varying dielectric function, ε(r). Inspired by nonequilibrium versions of PCMs, we develop a similar formalism within the context of Poisson's equation that includes the out-of-equilibrium dielectric response that accompanies a sudden change in the electron density of the solute, such as that which occurs in a vertical ionization process. A multigrid solver for Poisson's equation is developed to accommodate the large spatial grids necessary to discretize the three-dimensional electron density. We apply this methodology to compute vertical ionization energies (VIEs) of various solutes at the air/water interface and compare them to VIEs computed in bulk water, finding only very small differences between the two environments. VIEs computed using approximately two solvation shells of explicit water molecules are in excellent agreement with experiment for F - (aq), Cl - (aq), neat liquid water, and the hydrated electron, although errors for Li + (aq) and Na + (aq) are somewhat larger. Nonequilibrium corrections modify VIEs by up to 1.2 eV, relative to models based only on the static dielectric constant, and are therefore essential to obtain agreement with experiment. Given that the experiments (liquid microjet photoelectron spectroscopy) may be more sensitive to solutes situated at the air/water interface as compared to those in bulk water, our calculations provide some confidence that these experiments can indeed be interpreted as measurements of VIEs in bulk water.

The Effect of Mindful Listening Instruction on Listening Sensitivity and Enjoyment

ERIC Educational Resources Information Center

Anderson, William Todd

2012-01-01

The purpose of this study was to examine the effect of Mindful Listening Instruction on Music Listening Sensitivity and Music Listening Enjoyment. The type of mindfulness investigated in this study was of the social-psychological type, which shares both commonalities with and distinctions from meditative mindfulness. Enhanced context awareness,…

It Takes Two: Sensitive Caregiving across Contexts and Children's Social, Emotional, and Academic Outcomes

ERIC Educational Resources Information Center

Vesely, Colleen K.; Brown, Elizabeth Levine; Mahatmya, Duhita

2013-01-01

Research Findings: Using longitudinal survey data from the Welfare, Children, and Families Study: A Three-City Study ("n" = 135), this study examines how congruence in maternal and child care provider sensitivities contributes to young children's social, emotional, and academic outcomes among low-income minority families. Congruence…

Exchanging the Context between OGC Geospatial Web clients and GIS applications using Atom

NASA Astrophysics Data System (ADS)

Maso, Joan; Díaz, Paula; Riverola, Anna; Pons, Xavier

2013-04-01

Currently, the discovery and sharing of geospatial information over the web still presents difficulties. News distribution through website content was simplified by the use of Really Simple Syndication (RSS) and Atom syndication formats. This communication exposes an extension of Atom to redistribute references to geospatial information in a Spatial Data Infrastructure distributed environment. A geospatial client can save the status of an application that involves several OGC services of different kind and direct data and share this status with other users that need the same information and use different client vendor products in an interoperable way. The extensibility of the Atom format was essential to define a format that could be used in RSS enabled web browser, Mass Market map viewers and emerging geospatial enable integrated clients that support Open Geospatial Consortium (OGC) services. Since OWS Context has been designed as an Atom extension, it is possible to see the document in common places where Atom documents are valid. Internet web browsers are able to present the document as a list of items with title, abstract, time, description and downloading features. OWS Context uses GeoRSS so that, the document can be to be interpreted by both Google maps and Bing Maps as items that have the extent represented in a dynamic map. Another way to explode a OWS Context is to develop an XSLT to transform the Atom feed into an HTML5 document that shows the exact status of the client view window that saved the context document. To accomplish so, we use the width and height of the client window, and the extent of the view in world (geographic) coordinates in order to calculate the scale of the map. Then, we can mix elements in world coordinates (such as CF-NetCDF files or GML) with elements in pixel coordinates (such as WMS maps, WMTS tiles and direct SVG content). A smarter map browser application called MiraMon Map Browser is able to write a context document and read it again to recover the context of the previous view or load a context generated by another application. The possibility to store direct links to direct files in OWS Context is particularly interesting for GIS desktop solutions. This communication also presents the development made in the MiraMon desktop GIS solution to include OWS Context. MiraMon software is able to deal either with local files, web services and database connections. As in any other GIS solution, MiraMon team designed its own file (MiraMon Map MMM) for storing and sharing the status of a GIS session. The new OWS Context format is now adopted as an interoperable substitution of the MMM. The extensibility of the format makes it possible to map concepts in the MMM to current OWS Context elements (such as titles, data links, extent, etc) and to generate new elements that are able to include all extra metadata not currently covered by OWS Context. These developments were done in the nine edition of the OpenGIS Web Services Interoperability Experiment (OWS-9) and are demonstrated in this communication.

Context-Sensitive Grammar Transform: Compression and Pattern Matching

NASA Astrophysics Data System (ADS)

Maruyama, Shirou; Tanaka, Youhei; Sakamoto, Hiroshi; Takeda, Masayuki

A framework of context-sensitive grammar transform for speeding-up compressed pattern matching (CPM) is proposed. A greedy compression algorithm with the transform model is presented as well as a Knuth-Morris-Pratt (KMP)-type compressed pattern matching algorithm. The compression ratio is a match for gzip and Re-Pair, and the search speed of our CPM algorithm is almost twice faster than the KMP-type CPM algorithm on Byte-Pair-Encoding by Shibata et al.[18], and in the case of short patterns, faster than the Boyer-Moore-Horspool algorithm with the stopper encoding by Rautio et al.[14], which is regarded as one of the best combinations that allows a practically fast search.

Privacy in Georeferenced Context-Aware Services: A Survey

NASA Astrophysics Data System (ADS)

Riboni, Daniele; Pareschi, Linda; Bettini, Claudio

Location based services (LBS) are a specific instance of a broader class of Internet services that are predicted to become popular in a near future: context-aware services. The privacy concerns that LBS have raised are likely to become even more serious when several context data, other than location and time, are sent to service providers as part of an Internet request. This paper provides a classification and a brief survey of the privacy preservation techniques that have been proposed for this type of services. After identifying the benefits and shortcomings of each class of techniques, the paper proposes a combined approach to achieve a more comprehensive solution for privacy preservation in georeferenced context-aware services.

Development of technique for AR coating and nickel and copper metallization of solar cells. FPS Project: Product development

NASA Technical Reports Server (NTRS)

Taylor, W.

1982-01-01

Printed nickel overplated with copper and applied on top of a predeposited silicon nitride antireflective coating system for metallizing solar cells was analyzed. The ESL D and E paste formulations, and the new formulations F, G, H, and D-1 were evaluated. The nickel thick films were tested after firing for stability in the cleaning and plating solutions used in the Vanguard-Pacific brush plating process. It was found that the films are very sensitive to the leaning and alkaline copper solutions. Less sensitivity was displayed to the neutral copper solution. Microscopic and SEM observations show segregation of frit at the silicon nitride thick film interface with loose frit residues after lifting off plated grid lines.

Rapid solution of large-scale systems of equations

NASA Technical Reports Server (NTRS)

Storaasli, Olaf O.

1994-01-01

The analysis and design of complex aerospace structures requires the rapid solution of large systems of linear and nonlinear equations, eigenvalue extraction for buckling, vibration and flutter modes, structural optimization and design sensitivity calculation. Computers with multiple processors and vector capabilities can offer substantial computational advantages over traditional scalar computer for these analyses. These computers fall into two categories: shared memory computers and distributed memory computers. This presentation covers general-purpose, highly efficient algorithms for generation/assembly or element matrices, solution of systems of linear and nonlinear equations, eigenvalue and design sensitivity analysis and optimization. All algorithms are coded in FORTRAN for shared memory computers and many are adapted to distributed memory computers. The capability and numerical performance of these algorithms will be addressed.

Fast calculation of the sensitivity matrix in magnetic induction tomography by tetrahedral edge finite elements and the reciprocity theorem.

PubMed

Hollaus, K; Magele, C; Merwa, R; Scharfetter, H

2004-02-01

Magnetic induction tomography of biological tissue is used to reconstruct the changes in the complex conductivity distribution by measuring the perturbation of an alternating primary magnetic field. To facilitate the sensitivity analysis and the solution of the inverse problem a fast calculation of the sensitivity matrix, i.e. the Jacobian matrix, which maps the changes of the conductivity distribution onto the changes of the voltage induced in a receiver coil, is needed. The use of finite differences to determine the entries of the sensitivity matrix does not represent a feasible solution because of the high computational costs of the basic eddy current problem. Therefore, the reciprocity theorem was exploited. The basic eddy current problem was simulated by the finite element method using symmetric tetrahedral edge elements of second order. To test the method various simulations were carried out and discussed.

Knowing when to seek anger: Psychological health and context-sensitive emotional preferences.

PubMed

Kim, Min Y; Ford, Brett Q; Mauss, Iris; Tamir, Maya

2015-01-01

According to hedonic approaches to psychological health, healthy individuals should pursue pleasant and avoid unpleasant emotions. According to instrumental approaches, however, healthy individuals should pursue useful and avoid harmful emotions, whether pleasant or unpleasant. We sought to reconcile these approaches by distinguishing between preferences for emotions that are aggregated across contexts and preferences for emotions within specific contexts. Across five days, we assessed daily confrontational and collaborative demands and daily preferences for anger and happiness. Somewhat consistent with hedonic approaches, when averaging across contexts, psychologically healthier individuals wanted to feel less anger, but not more happiness. Somewhat consistent with instrumental approaches, when examined within contexts, psychologically healthier individuals wanted to feel angrier in more confrontational contexts, and some wanted to feel happier in more collaborative contexts. Thus, although healthier individuals are motivated to avoid unpleasant emotions over time, they are more motivated to experience them when they are potentially useful.

Vibration isolation technology: Sensitivity of selected classes of experiments to residual accelerations

NASA Technical Reports Server (NTRS)

Alexander, J. Iwan D.

1990-01-01

The solution was sought of a 2-D axisymmetric moving boundary problem for the sensitivity of isothermal and nonisothermal liquid columns and the sensitivity of thermo-capillary flows to buoyancy driven convection caused by residual accelerations. The sensitivity of a variety of space experiments to residual accelerations are examined. In all the cases discussed, the sensitivity is related to the dynamic response of a fluid. In some cases the sensitivity can be defined by the magnitude of the response of the velocity field. This response may involve motion of the fluid associated with internal density gradients, or the motion of a free liquid surface. For fluids with internal density gradients, the type of acceleration to which the experiment is sensitive will depend on whether buoyancy driven convection must be small in comparison to other types of fluid motion (such as thermocapillary flow), or fluid motion must be suppressed or eliminated (such as in diffusion studies, or directional solidification experiments). The effect of the velocity on the composition and temperature field must be considered, particularly in the vicinity of the melt crystal interface. As far as the response to transient disturbances is concerned the sensitivity is determined by both the magnitude and frequency the acceleration and the characteristic momentum and solute diffusion times.

Computational mechanics analysis tools for parallel-vector supercomputers

NASA Technical Reports Server (NTRS)

Storaasli, O. O.; Nguyen, D. T.; Baddourah, M. A.; Qin, J.

1993-01-01

Computational algorithms for structural analysis on parallel-vector supercomputers are reviewed. These parallel algorithms, developed by the authors, are for the assembly of structural equations, 'out-of-core' strategies for linear equation solution, massively distributed-memory equation solution, unsymmetric equation solution, general eigen-solution, geometrically nonlinear finite element analysis, design sensitivity analysis for structural dynamics, optimization algorithm and domain decomposition. The source code for many of these algorithms is available from NASA Langley.

Corrosion behavior of sensitized duplex stainless steel.

PubMed

Torres, F J; Panyayong, W; Rogers, W; Velasquez-Plata, D; Oshida, Y; Moore, B K

1998-01-01

The present work investigates the corrosion behavior of 2205 duplex stainless steel in 0.9% NaCl solution after various heat-treatments, and compares it to that of 316L austenitic stainless steel. Both stainless steels were heat-treated at 500, 650, and 800 degrees C in air for 1 h, followed by furnace cooling. Each heat-treated sample was examined for their microstructures and Vickers micro-hardness, and subjected to the X-ray diffraction for the phase identification. Using potentiostatic polarization method, each heat-treated sample was corrosion-tested in 37 degrees C 0.9% NaCl solution to estimate its corrosion rate. It was found that simulated sensitization showed an adverse influence on both steels, indicating that corrosion rates increased by increasing the sensitization temperatures.

pH-sensitive ion-selective field-effect transistor with zirconium dioxide film

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

Vlasov, Yu.G.; Bratov, A.V.; Tarantov, Yu.A.

1988-09-20

Miniature semiconductor pH sensors for liquid media, i.e., ion-selective field-effect transistors (ISFETs), are silicon field-effect transistors with a two-layer dielectric consisting of a passivating SiO/sub 2/ layer adjoining the silicon and a layer of pH-sensitive material in contact with the electrolyte solution to be tested. This study was devoted to the characteristics of pH-sensitive ISFETs with ZrO/sub 2/ films. The base was p-type silicon (KDB-10) with a (100) surface orientation. A ZrO/sub 2/ layer 10-50 nm thick was applied over the SiO/sub 2/ layer by electron-beam deposition. The measurements were made in aqueous KNO/sub 3/ or KCl solutions.

Security and Dependability Solutions for Web Services and Workflows

NASA Astrophysics Data System (ADS)

Kokolakis, Spyros; Rizomiliotis, Panagiotis; Benameur, Azzedine; Sinha, Smriti Kumar

In this chapter we present an innovative approach towards the design and application of Security and Dependability (S&D) solutions for Web services and service-based workflows. Recently, several standards have been published that prescribe S&D solutions for Web services, e.g. OASIS WS-Security. However,the application of these solutions in specific contexts has been proven problematic. We propose a new framework for the application of such solutions based on the SERENITY S&D Pattern concept. An S&D Pattern comprises all the necessary information for the implementation, verification, deployment, and active monitoring of an S&D Solution. Thus, system developers may rely on proven solutions that are dynamically deployed and monitored by the Serenity Runtime Framework. Finally, we further extend this approach to cover the case of executable workflows which are realised through the orchestration of Web services.

Adiabatic pumping solutions in global AdS

NASA Astrophysics Data System (ADS)

Carracedo, Pablo; Mas, Javier; Musso, Daniele; Serantes, Alexandre

2017-05-01

We construct a family of very simple stationary solutions to gravity coupled to a massless scalar field in global AdS. They involve a constantly rising source for the scalar field at the boundary and thereby we name them pumping solutions. We construct them numerically in D = 4. They are regular and, generically, have negative mass. We perform a study of linear and nonlinear stability and find both stable and unstable branches. In the latter case, solutions belonging to different sub-branches can either decay to black holes or to limiting cycles. This observation motivates the search for non-stationary exactly timeperiodic solutions which we actually construct. We clarify the role of pumping solutions in the context of quasistatic adiabatic quenches. In D = 3 the pumping solutions can be related to other previously known solutions, like magnetic or translationally-breaking backgrounds. From this we derive an analytic expression.

Reconfigurability in MDO Problem Synthesis. Part 1

NASA Technical Reports Server (NTRS)

Alexandrov, Natalia M.; Lewis, Robert Michael

2004-01-01

Integrating autonomous disciplines into a problem amenable to solution presents a major challenge in realistic multidisciplinary design optimization (MDO). We propose a linguistic approach to MDO problem description, formulation, and solution we call reconfigurable multidisciplinary synthesis (REMS). With assistance from computer science techniques, REMS comprises an abstract language and a collection of processes that provide a means for dynamic reasoning about MDO problems in a range of contexts. The approach may be summarized as follows. Description of disciplinary data according to the rules of a grammar, followed by lexical analysis and compilation, yields basic computational components that can be assembled into various MDO problem formulations and solution algorithms, including hybrid strategies, with relative ease. The ability to re-use the computational components is due to the special structure of the MDO problem. The range of contexts for reasoning about MDO spans tasks from error checking and derivative computation to formulation and reformulation of optimization problem statements. In highly structured contexts, reconfigurability can mean a straightforward transformation among problem formulations with a single operation. We hope that REMS will enable experimentation with a variety of problem formulations in research environments, assist in the assembly of MDO test problems, and serve as a pre-processor in computational frameworks in production environments. This paper, Part 1 of two companion papers, discusses the fundamentals of REMS. Part 2 illustrates the methodology in more detail.

Reconfigurability in MDO Problem Synthesis. Part 2

NASA Technical Reports Server (NTRS)

Alexandrov, Natalia M.; Lewis, Robert Michael

2004-01-01

Integrating autonomous disciplines into a problem amenable to solution presents a major challenge in realistic multidisciplinary design optimization (MDO). We propose a linguistic approach to MDO problem description, formulation, and solution we call reconfigurable multidisciplinary synthesis (REMS). With assistance from computer science techniques, REMS comprises an abstract language and a collection of processes that provide a means for dynamic reasoning about MDO problems in a range of contexts. The approach may be summarized as follows. Description of disciplinary data according to the rules of a grammar, followed by lexical analysis and compilation, yields basic computational components that can be assembled into various MDO problem formulations and solution algorithms, including hybrid strategies, with relative ease. The ability to re-use the computational components is due to the special structure of the MDO problem. The range of contexts for reasoning about MDO spans tasks from error checking and derivative computation to formulation and reformulation of optimization problem statements. In highly structured contexts, reconfigurability can mean a straightforward transformation among problem formulations with a single operation. We hope that REMS will enable experimentation with a variety of problem formulations in research environments, assist in the assembly of MDO test problems, and serve as a pre-processor in computational frameworks in production environments. Part 1 of two companion papers, discusses the fundamentals of REMS. This paper, Part 2 illustrates the methodology in more detail.

Why Representations?

ERIC Educational Resources Information Center

Schultz, James E.; Waters, Michael S.

2000-01-01

Discusses representations in the context of solving a system of linear equations. Views representations (concrete, tables, graphs, algebraic, matrices) from perspectives of understanding, technology, generalization, exact versus approximate solution, and learning style. (KHR)

Implicit Acquisition of Grammars with Crossed and Nested Non-Adjacent Dependencies: Investigating the Push-Down Stack Model

ERIC Educational Resources Information Center

Udden, Julia; Ingvar, Martin; Hagoort, Peter; Petersson, Karl M.

2012-01-01

A recent hypothesis in empirical brain research on language is that the fundamental difference between animal and human communication systems is captured by the distinction between finite-state and more complex phrase-structure grammars, such as context-free and context-sensitive grammars. However, the relevance of this distinction for the study…

Supervisor Assessment of Clinical and Professional Competence of Medical Trainees: A Reliability Study Using Workplace Data and a Focused Analytical Literature Review

ERIC Educational Resources Information Center

McGill, D. A.; van der Vleuten, C. P. M.; Clarke, M. J.

2011-01-01

Even though rater-based judgements of clinical competence are widely used, they are context sensitive and vary between individuals and institutions. To deal adequately with rater-judgement unreliability, evaluating the reliability of workplace rater-based assessments in the local context is essential. Using such an approach, the primary intention…

The Role of Drama on Cultural Sensitivity, Motivation and Literacy in a Second Language Context

ERIC Educational Resources Information Center

Bournot-Trites, Monique; Belliveau, George; Spiliotopoulos, Valia; Séror, Jérémie

2007-01-01

Although drama has been used successfully in English as a second language and has been shown to have positive effects on achievement and on self-confidence and motivation in various studies, it has received little attention in French immersion context where subjects are taught in French, the second language of students. The objective of this study…

Validating a Culturally-Sensitive Social Competence Training Programme for Adolescents with ASD in a Chinese Context: An Initial Investigation

ERIC Educational Resources Information Center

Chan, Raymond Won Shing; Leung, Cecilia Nga Wing; Ng, Denise Ching Yiu; Yau, Sania Sau Wai

2018-01-01

Previous studies on social skills training on ASD were done almost exclusively in the West with children as the main subjects. Demonstrations of the applicability of social interventions in different cultures and age groups are warranted. The current study outlined the development and preliminary evaluation of a CBT-context-based social competence…

Effect of oxytocin receptor blockade on appetite for sugar is modified by social context.

PubMed

Olszewski, Pawel K; Allen, Kerry; Levine, Allen S

2015-03-01

Research on oxytocin (OT) has yielded two seemingly unrelated sets of discoveries: OT has prosocial effects, and it elicits termination of feeding, especially of food rich in carbohydrates. Here we investigated whether OT's involvement in food intake is affected by the social context in mice, with particular focus on the role of dominance. We used two approaches: injections and gene expression analysis. We housed two males per cage and determined a dominant one. Then we injected a blood-brain barrier penetrant OT receptor antagonist L-368,899 in either dominant or subordinate animals and gave them 10-min access to a sucrose solution in the apparatus in which social exposure was modified and it ranged from none to unrestricted contact. L-368,899 increased the amount of consumed sugar in dominant mice regardless of whether these animals had access to sucrose in the non-social or social contexts (olfactory-derived or partial social exposure). The antagonist also increased the proportion of time that dominant mice spent drinking the sweet solution in the paradigm in which both mice had to share a single source of sucrose. L-368,899-treated subordinate mice consumed more sucrose solution than saline controls only when the environment in which sugar was presented was devoid of social cues related to the dominant animal. Finally, we investigated whether hypothalamic OT gene expression differs between dominant and subordinate mice consuming sugar and found OT mRNA levels to be higher in dominant mice. We conclude that social context and dominance affect OT's effect on appetite for sucrose. Copyright © 2014 Elsevier Ltd. All rights reserved.

Design and Preparation of Nanoparticle Dimers for SERS Detection

DTIC Science & Technology

2012-09-10

sensitivity afforded by surface enhanced Raman spectroscopy (SERS). Metal nanoparticles dimers were synthesized that incorporate SERS reporters...and antigens, based on the remarkable sensitivity afforded by surface enhanced Raman spectroscopy (SERS). Metal nanoparticles dimers were...Potma, V. A._Apkarian. High Sensitivity Surface-Enhanced Raman Scattering in Solution Using Engineered Silver Nanosphere Dimers, The Journal of

Determinants of Prosocial Behavior in Included Versus Excluded Contexts

PubMed Central

Cuadrado, Esther; Tabernero, Carmen; Steinel, Wolfgang

2016-01-01

Prosocial behavior (PSB) is increasingly becoming necessary as more and more individuals experience exclusion. In this context it is important to understand the motivational determinants of PSB. Here we report two experiments which analyzed the influence of dispositional (prosocialness; rejection sensitivity) and motivational variables (prosocial self-efficacy; prosocial collective efficacy; trust; anger; social affiliation motivation) on PSB under neutral contexts (Study 1), and once under inclusion or exclusion conditions (Study 2). Both studies provided evidence for the predicted mediation of PSB. Results in both neutral and inclusion and exclusion conditions supported our predictive model of PSB. In the model dispositional variables predicted motivational variables, which in turn predicted PSB. We showed that the investigated variables predicted PSB; this suggests that to promote PSB one could (1) foster prosocialness, prosocial self and collective efficacy, trust in others and affiliation motivation and (2) try to reduce negative feelings and the tendency to dread rejection in an attempt to reduce the negative impact that these variables have on PSB. Moreover, the few differences that emerged in the model between the inclusion and exclusion contexts suggested that in interventions with excluded individuals special care emphasis should be placed on addressing rejection sensitivity and lack of trust. PMID:26779103

Extinction and renewal of cue-elicited reward-seeking.

PubMed

Bezzina, Louise; Lee, Jessica C; Lovibond, Peter F; Colagiuri, Ben

2016-12-01

Reward cues can contribute to overconsumption of food and drugs and can relapse. The failure of exposure therapies to reduce overconsumption and relapse is generally attributed to the context-specificity of extinction. However, no previous study has examined whether cue-elicited reward-seeking (as opposed to cue-reactivity) is sensitive to context renewal. We tested this possibility in 160 healthy volunteers using a Pavlovian-instrumental transfer (PIT) design involving voluntary responding for a high value natural reward (chocolate). One reward cue underwent Pavlovian extinction in the same (Group AAA) or different context (Group ABA) to all other phases. This cue was compared with a second non-extinguished reward cue and an unpaired control cue. There was a significant overall PIT effect with both reward cues eliciting reward-seeking on test relative to the unpaired cue. Pavlovian extinction substantially reduced this effect, with the extinguished reward cue eliciting less reward-seeking than the non-extinguished reward cue. Most interestingly, extinction of cue-elicited reward-seeking was sensitive to renewal, with extinction less effective for reducing PIT when conducted in a different context. These findings have important implications for extinction-based interventions for reducing maladaptive reward-seeking in practice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Determinants of Prosocial Behavior in Included Versus Excluded Contexts.

PubMed

Cuadrado, Esther; Tabernero, Carmen; Steinel, Wolfgang

2015-01-01

Prosocial behavior (PSB) is increasingly becoming necessary as more and more individuals experience exclusion. In this context it is important to understand the motivational determinants of PSB. Here we report two experiments which analyzed the influence of dispositional (prosocialness; rejection sensitivity) and motivational variables (prosocial self-efficacy; prosocial collective efficacy; trust; anger; social affiliation motivation) on PSB under neutral contexts (Study 1), and once under inclusion or exclusion conditions (Study 2). Both studies provided evidence for the predicted mediation of PSB. Results in both neutral and inclusion and exclusion conditions supported our predictive model of PSB. In the model dispositional variables predicted motivational variables, which in turn predicted PSB. We showed that the investigated variables predicted PSB; this suggests that to promote PSB one could (1) foster prosocialness, prosocial self and collective efficacy, trust in others and affiliation motivation and (2) try to reduce negative feelings and the tendency to dread rejection in an attempt to reduce the negative impact that these variables have on PSB. Moreover, the few differences that emerged in the model between the inclusion and exclusion contexts suggested that in interventions with excluded individuals special care emphasis should be placed on addressing rejection sensitivity and lack of trust.

Explicit Context Matching in Content-Based Publish/Subscribe Systems

PubMed Central

Vavassori, Sergio; Soriano, Javier; Lizcano, David; Jiménez, Miguel

2013-01-01

Although context could be exploited to improve performance, elasticity and adaptation in most distributed systems that adopt the publish/subscribe (P/S) communication model, only a few researchers have focused on the area of context-aware matching in P/S systems and have explored its implications in domains with highly dynamic context like wireless sensor networks (WSNs) and IoT-enabled applications. Most adopted P/S models are context agnostic or do not differentiate context from the other application data. In this article, we present a novel context-aware P/S model. SilboPS manages context explicitly, focusing on the minimization of network overhead in domains with recurrent context changes related, for example, to mobile ad hoc networks (MANETs). Our approach represents a solution that helps to efficiently share and use sensor data coming from ubiquitous WSNs across a plethora of applications intent on using these data to build context awareness. Specifically, we empirically demonstrate that decoupling a subscription from the changing context in which it is produced and leveraging contextual scoping in the filtering process notably reduces (un)subscription cost per node, while improving the global performance/throughput of the network of brokers without altering the cost of SIENA-like topology changes. PMID:23529118

Evolution of Geometric Sensitivity Derivatives from Computer Aided Design Models

NASA Technical Reports Server (NTRS)

Jones, William T.; Lazzara, David; Haimes, Robert

2010-01-01

The generation of design parameter sensitivity derivatives is required for gradient-based optimization. Such sensitivity derivatives are elusive at best when working with geometry defined within the solid modeling context of Computer-Aided Design (CAD) systems. Solid modeling CAD systems are often proprietary and always complex, thereby necessitating ad hoc procedures to infer parameter sensitivity. A new perspective is presented that makes direct use of the hierarchical associativity of CAD features to trace their evolution and thereby track design parameter sensitivity. In contrast to ad hoc methods, this method provides a more concise procedure following the model design intent and determining the sensitivity of CAD geometry directly to its respective defining parameters.

Phynx: an open source software solution supporting data management and web-based patient-level data review for drug safety studies in the general practice research database and other health care databases.

PubMed

Egbring, Marco; Kullak-Ublick, Gerd A; Russmann, Stefan

2010-01-01

To develop a software solution that supports management and clinical review of patient data from electronic medical records databases or claims databases for pharmacoepidemiological drug safety studies. We used open source software to build a data management system and an internet application with a Flex client on a Java application server with a MySQL database backend. The application is hosted on Amazon Elastic Compute Cloud. This solution named Phynx supports data management, Web-based display of electronic patient information, and interactive review of patient-level information in the individual clinical context. This system was applied to a dataset from the UK General Practice Research Database (GPRD). Our solution can be setup and customized with limited programming resources, and there is almost no extra cost for software. Access times are short, the displayed information is structured in chronological order and visually attractive, and selected information such as drug exposure can be blinded. External experts can review patient profiles and save evaluations and comments via a common Web browser. Phynx provides a flexible and economical solution for patient-level review of electronic medical information from databases considering the individual clinical context. It can therefore make an important contribution to an efficient validation of outcome assessment in drug safety database studies.

Sensitivity of grounding line dynamics to basal conditions

NASA Astrophysics Data System (ADS)

Gagliardini, O.; Brondex, J.; Chauveau, G.; Gillet-chaulet, F.; Durand, G.

2017-12-01

In the context of a warming climate, the dynamical contribution of Antarctica to future sea level rise is still tainted by high uncertainties. Among the processes entering these uncertainties is the link between basal hydrology, friction and grounding line dynamics. Recent works have shown how sensitive is the response of the grounding line retreat to the choice of the form of the friction law. Indeed, starting from the same initial state, grounding line retreat rates can range over almost two orders of magnitude depending on the friction law formulation.Here, we use a phenomenological law that depends on the water pressure and allows a continuous transition from a Weertman-type friction at low water pressure to a Coulomb-type friction at high water pressure. This friction law depends on two main parameters that control the Weertman and Coulomb regimes. The range of values for these two parameters is only weakly physically constrained, and it can be shown that, for a given basal shear stress, different couples of parameters can conduct to the same sliding velocity. In addition, we show that close to the grounding line where basal water pressure is high, determining these two parameters might conduct to an ill-posed inverse problem with no solution.The aim of this presentation is to discuss a methodology to guide the choice of the two friction parameters and explore the sensitivity of the grounding line dynamics to this initial choice. We present results obtained both on a synthetic configuration used by the Marine Ice Sheet Model Intercomparison exercise and for the Amundsen sea sector using the experiments proposed by InitMIP-Antarctica, the first exercise in a series of ISMIP6 ice-sheet model intercomparison activities.

Learning context modulates aversive taste strength in honey bees.

PubMed

de Brito Sanchez, Maria Gabriela; Serre, Marion; Avarguès-Weber, Aurore; Dyer, Adrian G; Giurfa, Martin

2015-03-01

The capacity of honey bees (Apis mellifera) to detect bitter substances is controversial because they ingest without reluctance different kinds of bitter solutions in the laboratory, whereas free-flying bees avoid them in visual discrimination tasks. Here, we asked whether the gustatory perception of bees changes with the behavioral context so that tastes that are less effective as negative reinforcements in a given context become more effective in a different context. We trained bees to discriminate an odorant paired with 1 mol l(-1) sucrose solution from another odorant paired with either distilled water, 3 mol l(-1) NaCl or 60 mmol l(-1) quinine. Training was either Pavlovian [olfactory conditioning of the proboscis extension reflex (PER) in harnessed bees], or mainly operant (olfactory conditioning of free-walking bees in a Y-maze). PER-trained and maze-trained bees were subsequently tested both in their original context and in the alternative context. Whereas PER-trained bees transferred their choice to the Y-maze situation, Y-maze-trained bees did not respond with a PER to odors when subsequently harnessed. In both conditioning protocols, NaCl and distilled water were the strongest and the weakest aversive reinforcement, respectively. A significant variation was found for quinine, which had an intermediate aversive effect in PER conditioning but a more powerful effect in the Y-maze, similar to that of NaCl. These results thus show that the aversive strength of quinine varies with the learning context, and reveal the plasticity of the bee's gustatory system. We discuss the experimental constraints of both learning contexts and focus on stress as a key modulator of taste in the honey bee. Further explorations of bee taste are proposed to understand the physiology of taste modulation in bees. © 2015. Published by The Company of Biologists Ltd.

Enhancing Primary Science: An Exploration of Teachers' Own Ideas of Solutions to Challenges in Inquiry- and Context-Based Teaching

ERIC Educational Resources Information Center

Walan, Susanne; Mc Ewen, Birgitta; Gericke, Niklas

2016-01-01

Studies of inquiry- and context-based science education (IC-BaSE) have shown that teachers find these approaches problematic. In this study, 12 primary school teachers' reflections on challenges related to IC-BaSE are explored. The aim of the study was to investigate which challenges primary teachers experience when working with IC-BaSE and how…

Dynamics of a Definition: A Framework to Analyse Student Construction of the Concept of Solution to a Differential Equation

ERIC Educational Resources Information Center

Raychaudhuri, Debasree

2008-01-01

In this note we develop a framework that makes explicit the inherent dynamic structure of certain mathematical definitions by means of the four facets of context-entity-process-object. These facets and their interrelations are then used to capture and interpret specific aspects of student constructions of the concept of solution to first order…

Development of Thin-film Dye-sensitized Photoactive Materials on Ultra High Molecular Weight Polyethylene

DTIC Science & Technology

2012-04-01

although it is used as a base in most paints due to its light scattering ability. In general, a pure anatase TiO2 nanostructure is preferred over...solution, 0.1%, 0.5%, and 1% of pristine graphene was added to each solution. The solution was then stirred for 15 min and then sonicated for 20 min

A piece of the action: Modulation of sensory-motor regions by action idioms and metaphors

PubMed Central

Desai, Rutvik H.; Conant, Lisa L.; Binder, Jeffrey R.; Park, Haeil; Seidenberg, Mark S.

2013-01-01

The idea that the conceptual system draws on sensory and motor systems has received considerable experimental support in recent years. Whether the tight coupling between sensory-motor and conceptual systems is modulated by factors such as context or task demands is a matter of controversy. Here, we tested the context sensitivity of this coupling by using action verbs in three different types of sentences in an fMRI study: literal action, apt but non-idiomatic action metaphors, and action idioms. Abstract sentences served as a baseline. The result showed involvement of sensory-motor areas for literal and metaphoric action sentences, but not for idiomatic ones. A trend of increasing sensory-motor activation from abstract to idiomatic to metaphoric to literal sentences was seen. These results support a gradual abstraction process whereby the reliance on sensory-motor systems is reduced as the abstractness of meaning as well as conventionalization is increased, highlighting the context sensitive nature of semantic processing. PMID:23891645

Culture and context: East Asian American and European American differences in P3 event-related potentials and self-construal.

PubMed

Lewis, Richard S; Goto, Sharon G; Kong, Lauren L

2008-05-01

Research has demonstrated differences in social and cognitive processes between East Asians and European Americans. Whereas East Asians have been characterized as being more sensitive to situational context and attending more to the perceptual field, European Americans have been characterized as being more focused on the object and being more field independent. The goal of the present experiment was to investigate differences in neural responses to target objects and stimulus context between East Asian Americans and European Americans using a three-stimulus novelty P3 event-related potential design. As hypothesized, European Americans displayed relatively greater target P3 amplitudes, indexing attention to target events, whereas East Asian Americans displayed relatively greater novelty P3 amplitudes, indexing attention to contextually deviant events. Furthermore, the authors found that interdependent self-construal mediated the relationship between culture and the novelty P3. These findings identify a specific pattern of neural activity associated with established cultural differences in contextual sensitivity.

A piece of the action: modulation of sensory-motor regions by action idioms and metaphors.

PubMed

Desai, Rutvik H; Conant, Lisa L; Binder, Jeffrey R; Park, Haeil; Seidenberg, Mark S

2013-12-01

The idea that the conceptual system draws on sensory and motor systems has received considerable experimental support in recent years. Whether the tight coupling between sensory-motor and conceptual systems is modulated by factors such as context or task demands is a matter of controversy. Here, we tested the context sensitivity of this coupling by using action verbs in three different types of sentences in an fMRI study: literal action, apt but non-idiomatic action metaphors, and action idioms. Abstract sentences served as a baseline. The result showed involvement of sensory-motor areas for literal and metaphoric action sentences, but not for idiomatic ones. A trend of increasing sensory-motor activation from abstract to idiomatic to metaphoric to literal sentences was seen. These results support a gradual abstraction process whereby the reliance on sensory-motor systems is reduced as the abstractness of meaning as well as conventionalization is increased, highlighting the context sensitive nature of semantic processing. © 2013.

What does the closure of context-sensitive constraints mean for determinism, autonomy, self-determination, and agency?

PubMed

Juarrero, Alicia

2015-12-01

The role of context-sensitive constraints - first as enablers of complexification and subsequently as regulators that maintain the integrity of self-organized, coherent wholes - has only recently begun to be examined. Conceptualizing such organizational constraints in terms of the operations of far from equilibrium, nonlinear dynamic processes rekindles old metaphysical discussions concerning primary and secondary relations, emergence, causality, and the logic of explanation. In particular, far-from-equilibrium processes allow us to rethink how parts-to-whole and whole-to-parts - so-called "mereological"- relationships are constituted. A renewed understanding of recursive feedback and the role context-dependence plays in generating the boundary conditions and the internal organization of complex adaptive systems in turn allows us to redescribe formal and final cause in such a way as to provide a meaningful sense of heretofore seemingly intractable philosophical problems such as autonomy, self-determination, and agency. Copyright © 2015. Published by Elsevier Ltd.

Exact analytic solution for non-linear density fluctuation in a ΛCDM universe

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

Yoo, Jaiyul; Gong, Jinn-Ouk, E-mail: jyoo@physik.uzh.ch, E-mail: jinn-ouk.gong@apctp.org

We derive the exact third-order analytic solution of the matter density fluctuation in the proper-time hypersurface in a ΛCDM universe, accounting for the explicit time-dependence and clarifying the relation to the initial condition. Furthermore, we compare our analytic solution to the previous calculation in the comoving gauge, and to the standard Newtonian perturbation theory by providing Fourier kernels for the relativistic effects. Our results provide an essential ingredient for a complete description of galaxy bias in the relativistic context.

The role of artificial intelligence techniques in scheduling systems

NASA Technical Reports Server (NTRS)

Geoffroy, Amy L.; Britt, Daniel L.; Gohring, John R.

1990-01-01

Artificial Intelligence (AI) techniques provide good solutions for many of the problems which are characteristic of scheduling applications. However, scheduling is a large, complex heterogeneous problem. Different applications will require different solutions. Any individual application will require the use of a variety of techniques, including both AI and conventional software methods. The operational context of the scheduling system will also play a large role in design considerations. The key is to identify those places where a specific AI technique is in fact the preferable solution, and to integrate that technique into the overall architecture.

Solution nuclear magnetic resonance spectroscopy on a nanostructured diamond chip.

PubMed

Kehayias, P; Jarmola, A; Mosavian, N; Fescenko, I; Benito, F M; Laraoui, A; Smits, J; Bougas, L; Budker, D; Neumann, A; Brueck, S R J; Acosta, V M

2017-08-04

Sensors using nitrogen-vacancy centers in diamond are a promising tool for small-volume nuclear magnetic resonance (NMR) spectroscopy, but the limited sensitivity remains a challenge. Here we show nearly two orders of magnitude improvement in concentration sensitivity over previous nitrogen-vacancy and picoliter NMR studies. We demonstrate NMR spectroscopy of picoliter-volume solutions using a nanostructured diamond chip with dense, high-aspect-ratio nanogratings, enhancing the surface area by 15 times. The nanograting sidewalls are doped with nitrogen-vacancies located a few nanometers from the diamond surface to detect the NMR spectrum of roughly 1 pl of fluid lying within adjacent nanograting grooves. We perform 1 H and 19 F nuclear magnetic resonance spectroscopy at room temperature in magnetic fields below 50 mT. Using a solution of CsF in glycerol, we determine that 4 ± 2 × 10 12 19 F spins in a 1 pl volume can be detected with a signal-to-noise ratio of 3 in 1 s of integration.Nitrogen vacancy (NV) centres in diamond can be used for NMR spectroscopy, but increased sensitivity is needed to avoid long measurement times. Kehayias et al. present a nanostructured diamond grating with a high density of NV centres, enabling NMR spectroscopy of picoliter-volume solutions.

Lunar Rotation and the Lunar Interior

NASA Technical Reports Server (NTRS)

Williams, J. G.; Boggs, D. H.; Ratcliff, J. T.; Dickey, J. O.

2003-01-01

Variations in rotation and orientation of the Moon are sensitive to solid-body tidal dissipation, dissipation due to relative motion at the fluid-core/ solid-mantle boundary, and tidal Love number k2. There is weaker sensitivity to flattening of the core-mantle boundary (CMB) and fluid core moment of inertia. Accurate Lunar Laser Ranging (LLR) measurements of the distance from observatories on the Earth to four retroreflector arrays on the Moon are sensitive to lunar rotation and orientation variations and tidal displacements. Past solutions using the LLR data have given results for dissipation due to solid-body tides and fluid core plus Love number. Past detection of CMB flattening has been marginal but is improving, while direct detection of the core moment has not yet been achieved. Three decades of Lunar Laser Ranging (LLR) data are analyzed using a weighted least-squares approach. The lunar solution parameters include dissipation at the fluid-core/solid-mantle boundary, tidal dissipation, dissipation-related coefficients for rotation and orientation terms, potential Love number k2, a correction to the constant term in the tilt of the equator to the ecliptic which is meant to approximate the influence of core-mantle boundary flattening, and displacement Love numbers h2 and l2. Several solutions, with different combinations of solution parameters and constraints, are considered.

Focus Groups in Qualitative Research: Culturally Sensitive Methodology for the Arabian Gulf?

ERIC Educational Resources Information Center

Thomas, Andrew

2008-01-01

This article explores whether focus groups can constitute a culturally sensitive method of data gathering for educational leadership, management and related areas in a Gulf-Arab cultural context. Reviewing the literature on focus groups and cross-cultural psychology for the Arab region, it identifies key notions related to societal values such as…

A Pilot Study of Maternal Sensitivity in the Context of Emergent Autism

ERIC Educational Resources Information Center

Baker, Jason K.; Messinger, Daniel S.; Lyons, Kara K.; Grantz, Caroline J.

2010-01-01

Unstructured mother-toddler interactions were examined in 18-month-old high- and low-risk children subsequently diagnosed (n = 12) or not diagnosed (n = 21) with autism spectrum disorders (ASD) at 36 months. Differences in maternal sensitivity were not found as a function of emergent ASD status. A differential-susceptibility moderation model of…

The Relation of Maternal Sensitivity to Children's Internalizing and Externalizing Problems within the Context of Maternal Depressive Symptoms

ERIC Educational Resources Information Center

Garai, Emily Priscilla; Forehand, Rex L.; Colletti, Christina J. M.; Reeslund, Kristen; Potts, Jennifer; Compas, Bruce

2009-01-01

Maternal depression has been linked to deficits in parenting that contribute to youth's development of externalizing and/or internalizing problems. Maternal sensitivity has been implicated within the infant literature as a foundational aspect of parenting contributing to a child's adjustment. This study examines the main and moderating effects of…

Optimizing EFL Learners' Sensitizing Reading Skill: Development of Local Content-Based Textbook

ERIC Educational Resources Information Center

Arifani, Yudhi

2016-01-01

The development of local wisdom based sensitizing reading material is aimed at penetrating one of the imperishable gaps between authentic and non-authentic reading materials dispute in an EFL teaching context. Promoting EFL learners' needs for the first semester students of English department at university level, who rarely or even never have a…

Pressure Sensitivity Kernels Applied to Time-reversal Acoustics

DTIC Science & Technology

2009-06-29

experimental data, along with an internal wave model, using various metrics. The linear limitations of the kernels are explored in the context of time...Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 82 3.A Internal wave modeling . . . . . . . . . . . . . . . . . . . 82 Bibliography...multipaths corresponding to direct path, single surface/bottom bounce, double bounce off the surface and bot- tom, Bottom: Time-domain sensitivity kernel for

Losing Control in Social Situations: How the Presence of Others Affects Neural Processes Related to Sense of Agency

PubMed Central

Fleming, Stephen

2018-01-01

Social contexts substantially influence individual behavior, but little is known about how they affect cognitive processes related to voluntary action. Previously, it has been shown that social context reduces participants’ sense of agency over the outcomes of their actions and outcome monitoring. In this fMRI study on human volunteers, we investigated the neural mechanisms by which social context alters sense of agency. Participants made costly actions to stop inflating a balloon before it burst. On “social” trials, another player could act in their stead, but we analyzed only trials in which the other player remained passive. We hypothesized that mentalizing processes during social trials would affect decision-making fluency and lead to a decreased sense of agency. In line with this hypothesis, we found increased activity in the bilateral temporo-parietal junction (TPJ), precuneus, and middle frontal gyrus during social trials compared with nonsocial trials. Activity in the precuneus was, in turn, negatively related to sense of agency at a single-trial level. We further found a double dissociation between TPJ and angular gyrus (AG): activity in the left AG was not sensitive to social context but was negatively related to sense of agency. In contrast, activity in the TPJ was modulated by social context but was not sensitive to sense of agency. PMID:29527568

Losing Control in Social Situations: How the Presence of Others Affects Neural Processes Related to Sense of Agency.

PubMed

Beyer, Frederike; Sidarus, Nura; Fleming, Stephen; Haggard, Patrick

2018-01-01

Social contexts substantially influence individual behavior, but little is known about how they affect cognitive processes related to voluntary action. Previously, it has been shown that social context reduces participants' sense of agency over the outcomes of their actions and outcome monitoring. In this fMRI study on human volunteers, we investigated the neural mechanisms by which social context alters sense of agency. Participants made costly actions to stop inflating a balloon before it burst. On "social" trials, another player could act in their stead, but we analyzed only trials in which the other player remained passive. We hypothesized that mentalizing processes during social trials would affect decision-making fluency and lead to a decreased sense of agency. In line with this hypothesis, we found increased activity in the bilateral temporo-parietal junction (TPJ), precuneus, and middle frontal gyrus during social trials compared with nonsocial trials. Activity in the precuneus was, in turn, negatively related to sense of agency at a single-trial level. We further found a double dissociation between TPJ and angular gyrus (AG): activity in the left AG was not sensitive to social context but was negatively related to sense of agency. In contrast, activity in the TPJ was modulated by social context but was not sensitive to sense of agency.

Hearing impairment, cognition and speech understanding: exploratory factor analyses of a comprehensive test battery for a group of hearing aid users, the n200 study

PubMed Central

Rönnberg, Jerker; Lunner, Thomas; Ng, Elaine Hoi Ning; Lidestam, Björn; Zekveld, Adriana Agatha; Sörqvist, Patrik; Lyxell, Björn; Träff, Ulf; Yumba, Wycliffe; Classon, Elisabet; Hällgren, Mathias; Larsby, Birgitta; Signoret, Carine; Pichora-Fuller, M. Kathleen; Rudner, Mary; Danielsson, Henrik; Stenfelt, Stefan

2016-01-01

Abstract Objective: The aims of the current n200 study were to assess the structural relations between three classes of test variables (i.e. HEARING, COGNITION and aided speech-in-noise OUTCOMES) and to describe the theoretical implications of these relations for the Ease of Language Understanding (ELU) model. Study sample: Participants were 200 hard-of-hearing hearing-aid users, with a mean age of 60.8 years. Forty-three percent were females and the mean hearing threshold in the better ear was 37.4 dB HL. Design: LEVEL1 factor analyses extracted one factor per test and/or cognitive function based on a priori conceptualizations. The more abstract LEVEL 2 factor analyses were performed separately for the three classes of test variables. Results: The HEARING test variables resulted in two LEVEL 2 factors, which we labelled SENSITIVITY and TEMPORAL FINE STRUCTURE; the COGNITIVE variables in one COGNITION factor only, and OUTCOMES in two factors, NO CONTEXT and CONTEXT. COGNITION predicted the NO CONTEXT factor to a stronger extent than the CONTEXT outcome factor. TEMPORAL FINE STRUCTURE and SENSITIVITY were associated with COGNITION and all three contributed significantly and independently to especially the NO CONTEXT outcome scores (R2 = 0.40). Conclusions: All LEVEL 2 factors are important theoretically as well as for clinical assessment. PMID:27589015

Hearing impairment, cognition and speech understanding: exploratory factor analyses of a comprehensive test battery for a group of hearing aid users, the n200 study.

PubMed

Rönnberg, Jerker; Lunner, Thomas; Ng, Elaine Hoi Ning; Lidestam, Björn; Zekveld, Adriana Agatha; Sörqvist, Patrik; Lyxell, Björn; Träff, Ulf; Yumba, Wycliffe; Classon, Elisabet; Hällgren, Mathias; Larsby, Birgitta; Signoret, Carine; Pichora-Fuller, M Kathleen; Rudner, Mary; Danielsson, Henrik; Stenfelt, Stefan

2016-11-01

The aims of the current n200 study were to assess the structural relations between three classes of test variables (i.e. HEARING, COGNITION and aided speech-in-noise OUTCOMES) and to describe the theoretical implications of these relations for the Ease of Language Understanding (ELU) model. Participants were 200 hard-of-hearing hearing-aid users, with a mean age of 60.8 years. Forty-three percent were females and the mean hearing threshold in the better ear was 37.4 dB HL. LEVEL1 factor analyses extracted one factor per test and/or cognitive function based on a priori conceptualizations. The more abstract LEVEL 2 factor analyses were performed separately for the three classes of test variables. The HEARING test variables resulted in two LEVEL 2 factors, which we labelled SENSITIVITY and TEMPORAL FINE STRUCTURE; the COGNITIVE variables in one COGNITION factor only, and OUTCOMES in two factors, NO CONTEXT and CONTEXT. COGNITION predicted the NO CONTEXT factor to a stronger extent than the CONTEXT outcome factor. TEMPORAL FINE STRUCTURE and SENSITIVITY were associated with COGNITION and all three contributed significantly and independently to especially the NO CONTEXT outcome scores (R(2) = 0.40). All LEVEL 2 factors are important theoretically as well as for clinical assessment.

Size-dependent penetrant diffusion in polymer glasses.

PubMed

Meng, Dong; Zhang, Kai; Kumar, Sanat K

2018-05-18

Molecular Dynamics simulations are used to understand the underpinning basis of the transport of gas-like solutes in deeply quenched polymeric glasses. As found in previous work, small solutes, with sizes smaller than 0.15 times the chain monomer size, move as might be expected in a medium with large pores. In contrast, the motion of larger solutes is activated and is strongly facilitated by matrix motion. In particular, solute motion is coupled to the local elastic fluctuations of the matrix as characterized by the Debye-Waller factor. While similar ideas have been previously proposed for the viscosity of supercooled liquids above their glass transition, to our knowledge, this is the first illustration of this concept in the context of solute mass transport in deeply quenched polymer glasses.

A comparison of solute-transport solution techniques and their effect on sensitivity analysis and inverse modeling results

USGS Publications Warehouse

Mehl, S.; Hill, M.C.

2001-01-01

Five common numerical techniques for solving the advection-dispersion equation (finite difference, predictor corrector, total variation diminishing, method of characteristics, and modified method of characteristics) were tested using simulations of a controlled conservative tracer-test experiment through a heterogeneous, two-dimensional sand tank. The experimental facility was constructed using discrete, randomly distributed, homogeneous blocks of five sand types. This experimental model provides an opportunity to compare the solution techniques: the heterogeneous hydraulic-conductivity distribution of known structure can be accurately represented by a numerical model, and detailed measurements can be compared with simulated concentrations and total flow through the tank. The present work uses this opportunity to investigate how three common types of results - simulated breakthrough curves, sensitivity analysis, and calibrated parameter values - change in this heterogeneous situation given the different methods of simulating solute transport. The breakthrough curves show that simulated peak concentrations, even at very fine grid spacings, varied between the techniques because of different amounts of numerical dispersion. Sensitivity-analysis results revealed: (1) a high correlation between hydraulic conductivity and porosity given the concentration and flow observations used, so that both could not be estimated; and (2) that the breakthrough curve data did not provide enough information to estimate individual values of dispersivity for the five sands. This study demonstrates that the choice of assigned dispersivity and the amount of numerical dispersion present in the solution technique influence estimated hydraulic conductivity values to a surprising degree.

Application of Harmony Search algorithm to the solution of groundwater management models

NASA Astrophysics Data System (ADS)

Tamer Ayvaz, M.

2009-06-01

This study proposes a groundwater resources management model in which the solution is performed through a combined simulation-optimization model. A modular three-dimensional finite difference groundwater flow model, MODFLOW is used as the simulation model. This model is then combined with a Harmony Search (HS) optimization algorithm which is based on the musical process of searching for a perfect state of harmony. The performance of the proposed HS based management model is tested on three separate groundwater management problems: (i) maximization of total pumping from an aquifer (steady-state); (ii) minimization of the total pumping cost to satisfy the given demand (steady-state); and (iii) minimization of the pumping cost to satisfy the given demand for multiple management periods (transient). The sensitivity of HS algorithm is evaluated by performing a sensitivity analysis which aims to determine the impact of related solution parameters on convergence behavior. The results show that HS yields nearly same or better solutions than the previous solution methods and may be used to solve management problems in groundwater modeling.

Accuracy, Precision, Ease-Of-Use, and Cost of Methods to Test Ebola-Relevant Chlorine Solutions

PubMed Central

Wells, Emma; Wolfe, Marlene K.; Murray, Anna; Lantagne, Daniele

2016-01-01

To prevent transmission in Ebola Virus Disease (EVD) outbreaks, it is recommended to disinfect living things (hands and people) with 0.05% chlorine solution and non-living things (surfaces, personal protective equipment, dead bodies) with 0.5% chlorine solution. In the current West African EVD outbreak, these solutions (manufactured from calcium hypochlorite (HTH), sodium dichloroisocyanurate (NaDCC), and sodium hypochlorite (NaOCl)) have been widely used in both Ebola Treatment Unit and community settings. To ensure solution quality, testing is necessary, however test method appropriateness for these Ebola-relevant concentrations has not previously been evaluated. We identified fourteen commercially-available methods to test Ebola-relevant chlorine solution concentrations, including two titration methods, four DPD dilution methods, and six test strips. We assessed these methods by: 1) determining accuracy and precision by measuring in quintuplicate five different 0.05% and 0.5% chlorine solutions manufactured from NaDCC, HTH, and NaOCl; 2) conducting volunteer testing to assess ease-of-use; and, 3) determining costs. Accuracy was greatest in titration methods (reference-12.4% error compared to reference method), then DPD dilution methods (2.4–19% error), then test strips (5.2–48% error); precision followed this same trend. Two methods had an accuracy of <10% error across all five chlorine solutions with good precision: Hach digital titration for 0.05% and 0.5% solutions (recommended for contexts with trained personnel and financial resources), and Serim test strips for 0.05% solutions (recommended for contexts where rapid, inexpensive, and low-training burden testing is needed). Measurement error from test methods not including pH adjustment varied significantly across the five chlorine solutions, which had pH values 5–11. Volunteers found test strip easiest and titration hardest; costs per 100 tests were $14–37 for test strips and $33–609 for titration. Given the ease-of-use and cost benefits of test strips, we recommend further development of test strips robust to pH variation and appropriate for Ebola-relevant chlorine solution concentrations. PMID:27243817

Interaction of breathing localized solutions for subcritical bifurcations

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

Deissler, R.J.; Brand, H.R.

1995-06-12

We discuss interactions of spatially localized solutions, which breathe in the modulus, for coupled quintic complex Ginzburg-Landau equations. The interaction behavior is much richer than and qualitatively different from that of the fixed-shape solutions reported previously. The outcome of a collision can depend on the initial conditions, and, in particular, {ital sensitively} on the initial conditions for {ital chaotic} solutions, even though parameter values are unchanged. The novelty of these interactions, as compared to those of the fixed-shape solutions and to those of solitons is emphasized.

Statistical learning in social action contexts.

PubMed

Monroy, Claire; Meyer, Marlene; Gerson, Sarah; Hunnius, Sabine

2017-01-01

Sensitivity to the regularities and structure contained within sequential, goal-directed actions is an important building block for generating expectations about the actions we observe. Until now, research on statistical learning for actions has solely focused on individual action sequences, but many actions in daily life involve multiple actors in various interaction contexts. The current study is the first to investigate the role of statistical learning in tracking regularities between actions performed by different actors, and whether the social context characterizing their interaction influences learning. That is, are observers more likely to track regularities across actors if they are perceived as acting jointly as opposed to in parallel? We tested adults and toddlers to explore whether social context guides statistical learning and-if so-whether it does so from early in development. In a between-subjects eye-tracking experiment, participants were primed with a social context cue between two actors who either shared a goal of playing together ('Joint' condition) or stated the intention to act alone ('Parallel' condition). In subsequent videos, the actors performed sequential actions in which, for certain action pairs, the first actor's action reliably predicted the second actor's action. We analyzed predictive eye movements to upcoming actions as a measure of learning, and found that both adults and toddlers learned the statistical regularities across actors when their actions caused an effect. Further, adults with high statistical learning performance were sensitive to social context: those who observed actors with a shared goal were more likely to correctly predict upcoming actions. In contrast, there was no effect of social context in the toddler group, regardless of learning performance. These findings shed light on how adults and toddlers perceive statistical regularities across actors depending on the nature of the observed social situation and the resulting effects.

What drives young children to over-imitate? Investigating the effects of age, context, action type, and transitivity.

PubMed

Clay, Zanna; Over, Harriet; Tennie, Claudio

2018-02-01

Imitation underlies many traits thought to characterize our species, which includes the transmission and acquisition of language, material culture, norms, rituals, and conventions. From early childhood, humans show an intriguing willingness to imitate behaviors, even those that have no obvious function. This phenomenon, known as "over-imitation," is thought to explain some of the key differences between human cultures as compared with those of nonhuman animals. Here, we used a single integrative paradigm to simultaneously investigate several key factors proposed to shape children's over-imitation: age, context, transitivity, and action type. We compared typically developing children aged 4-6years in a task involving actions verbally framed as being instrumental, normative, or communicative in function. Within these contexts, we explored whether children were more likely to over-imitate transitive versus intransitive actions and manual versus body part actions. Results showed an interaction between age and context; as children got older, they were more likely to imitate within a normative context, whereas younger children were more likely to imitate in instrumental contexts. Younger children were more likely to imitate transitive actions (actions on objects) than intransitive actions compared with older children. Our results show that children are highly sensitive to even minimal cues to perceived context and flexibly adapt their imitation accordingly. As they get older, children's imitation appears to become less object bound, less focused on instrumental outcomes, and more sensitive to normative cues. This shift is consistent with the proposal that over-imitation becomes increasingly social in its function as children move through childhood and beyond. Copyright © 2017 Elsevier Inc. All rights reserved.

Statistical learning in social action contexts

PubMed Central

Meyer, Marlene; Gerson, Sarah; Hunnius, Sabine

2017-01-01

Sensitivity to the regularities and structure contained within sequential, goal-directed actions is an important building block for generating expectations about the actions we observe. Until now, research on statistical learning for actions has solely focused on individual action sequences, but many actions in daily life involve multiple actors in various interaction contexts. The current study is the first to investigate the role of statistical learning in tracking regularities between actions performed by different actors, and whether the social context characterizing their interaction influences learning. That is, are observers more likely to track regularities across actors if they are perceived as acting jointly as opposed to in parallel? We tested adults and toddlers to explore whether social context guides statistical learning and—if so—whether it does so from early in development. In a between-subjects eye-tracking experiment, participants were primed with a social context cue between two actors who either shared a goal of playing together (‘Joint’ condition) or stated the intention to act alone (‘Parallel’ condition). In subsequent videos, the actors performed sequential actions in which, for certain action pairs, the first actor’s action reliably predicted the second actor’s action. We analyzed predictive eye movements to upcoming actions as a measure of learning, and found that both adults and toddlers learned the statistical regularities across actors when their actions caused an effect. Further, adults with high statistical learning performance were sensitive to social context: those who observed actors with a shared goal were more likely to correctly predict upcoming actions. In contrast, there was no effect of social context in the toddler group, regardless of learning performance. These findings shed light on how adults and toddlers perceive statistical regularities across actors depending on the nature of the observed social situation and the resulting effects. PMID:28475619

Sensitive ionization of non-volatile analytes using protein solutions as spray liquid in desorption electrospray ionization mass spectrometry.

PubMed

Zhu, Zhiqiang; Han, Jing; Zhang, Yan; Zhou, Yafei; Xu, Ning; Zhang, Bo; Gu, Haiwei; Chen, Huanwen

2012-12-15

Desorption electrospray ionization (DESI) is the most popular ambient ionization technique for direct analysis of complex samples without sample pretreatment. However, for many applications, especially for trace analysis, it is of interest to improve the sensitivity of DESI-mass spectrometry (MS). In traditional DESI-MS, a mixture of methanol/water/acetic acid is usually used to generate the primary ions. In this article, dilute protein solutions were electrosprayed in the DESI method to create multiply charged primary ions for the desorption ionization of trace analytes on various surfaces (e.g., filter paper, glass, Al-foil) without any sample pretreatment. The analyte ions were then detected and structurally characterized using a LTQ XL mass spectrometer. Compared with the methanol/water/acetic acid (49:49:2, v/v/v) solution, protein solutions significantly increased the signal levels of non-volatile compounds such as benzoic acid, TNT, o-toluidine, peptide and insulin in either positive or negative ion detection mode. For all the analytes tested, the limits of detection (LODs) were reduced to about half of the original values which were obtained using traditional DESI. The results showed that the signal enhancement is highly correlated with the molecular weight of the proteins and the selected solid surfaces. The proposed DESI method is a universal strategy for rapid and sensitive detection of trace amounts of strongly bound and/or non-volatile analytes, including explosives, peptides, and proteins. The results indicate that the sensitivity of DESI can be further improved by selecting larger proteins and appropriate solid surfaces. Copyright © 2012 John Wiley & Sons, Ltd.

Highly sensitive and selective detection of Al(III) ions in aqueous buffered solution with fluorescent peptide-based sensor.

PubMed

In, Byunggyu; Hwang, Gi Won; Lee, Keun-Hyeung

2016-09-15

A fluorescent sensor based on a tripeptide (SerGluGlu) with a dansyl fluorophore detected selectively Al(III) among 16 metal ions in aqueous buffered solutions without any organic cosolvent. The peptide-based sensor showed a highly sensitive turn on response to aluminium ion with high binding affinity (1.84×10(4)M(-1)) in aqueous buffered solutions. The detection limit (230nM, 5.98ppb) of the peptide-based sensor was much lower than the maximum allowable level (7.41μM) of aluminium ions in drinking water demanded by EPA. The binding mode of the peptide sensor with aluminium ions was characterized using ESI mass spectrometry, NMR titration, and pH titration experiments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Low-cost label-free electrical detection of artificial DNA nanostructures using solution-processed oxide thin-film transistors.

PubMed

Kim, Si Joon; Jung, Joohye; Lee, Keun Woo; Yoon, Doo Hyun; Jung, Tae Soo; Dugasani, Sreekantha Reddy; Park, Sung Ha; Kim, Hyun Jae

2013-11-13

A high-sensitivity, label-free method for detecting deoxyribonucleic acid (DNA) using solution-processed oxide thin-film transistors (TFTs) was developed. Double-crossover (DX) DNA nanostructures with different concentrations of divalent Cu ion (Cu(2+)) were immobilized on an In-Ga-Zn-O (IGZO) back-channel surface, which changed the electrical performance of the IGZO TFTs. The detection mechanism of the IGZO TFT-based DNA biosensor is attributed to electron trapping and electrostatic interactions caused by negatively charged phosphate groups on the DNA backbone. Furthermore, Cu(2+) in DX DNA nanostructures generates a current path when a gate bias is applied. The direct effect on the electrical response implies that solution-processed IGZO TFTs could be used to realize low-cost and high-sensitivity DNA biosensors.

Brilliant molecular nanocrystals emerging from sol-gel thin films: towards a new generation of fluorescent biochips.

PubMed

Dubuisson, E; Monnier, V; Sanz-Menez, N; Boury, B; Usson, Y; Pansu, R B; Ibanez, A

2009-08-05

To develop highly sensitive biosensors, we made directly available to biological aqueous solutions organic nanocrystals previously grown in the pores of sol-gel films. Through the controlled dissolution of the sol-gel surface, we obtained emerging nanocrystals that remained strongly anchored to the sol-gel coating for good mechanical stability of the final sensing device. We demonstrated that in the presence of a solution of DNA functionalized with a molecular probe, the nanocrystal fluorescence is strongly quenched by Förster resonance energy transfer thus opening the way towards very sensitive fluorescent biosensors through biomolecules grafted onto fluorescent nanocrystals. Finally, this controlled dissolution, involving weak concentrated NaOH solution, is a generic process that can be used for the thinning of any kind of sol-gel layer.

Simplified Method for Preparing Methylene-Blue-Sensitized Dichromated Gelatin

NASA Astrophysics Data System (ADS)

Kurokawa, Kazumasa; Koike, Satoshi; Namba, Sinji; Mizuno, Toru; Kubota, Toshihiro

1998-05-01

Methylene-blue-sensitized dichromated gelatin (MBDCG) is a suitable material for recording full-color holograms in a single layer. However, a drying process in an ammonia atmosphere is necessary to prepare the MBDCG plate. This process is time-consuming and unstable. A simplified method for preparing the MBDCG plate is presented in which the MBDCG can be dried without ammonia. Elimination of the drying process is possible when the methylene blue in MBDCG does not separate. This is achieved by a decrease in the concentration of dichromate in the photosensitized solution and the addition of an ammonia solution to the photosensitized solution. Last, the gelatin is allowed to gel. A Lippmann color hologram grating with a diffraction efficiency of more than 80% is obtained by use of this MBDCG.

An Analysis of Context-Aware Data Models for Smart Cities: Towards Fiware and Etsi Cim Emerging Data Model

NASA Astrophysics Data System (ADS)

Jara, A. J.; Bocchi, Y.; Fernandez, D.; Molina, G.; Gomez, A.

2017-09-01

Smart Cities requires the support of context-aware and enriched semantic descriptions to support a scalable and cross-domain development of smart applications. For example, nowadays general purpose sensors such as crowd monitoring (counting people in an area), environmental information (pollution, air quality, temperature, humidity, noise) etc. can be used in multiple solutions with different objectives. For that reason, a data model that offers advanced capabilities for the description of context is required. This paper presents an overview of the available technologies for this purpose and how it is being addressed by the Open and Agile Smart Cities principles and FIWARE platform through the data models defined by the ETSI ISG Context Information Management (ETSI CIM).

What do we know about developing patient portals? a systematic literature review.

PubMed

Otte-Trojel, Terese; de Bont, Antoinette; Rundall, Thomas G; van de Klundert, Joris

2016-04-01

Numerous articles have reported on the development of patient portals, including development problems and solutions. We review these articles to inform future patient portal development efforts and to provide a summary of the evidence base that can guide future research. We performed a systematic review of relevant literature to answer 5 questions: (1) What categories of problems related to patient portal development have been defined? (2) What causal factors have been identified by problem analysis and diagnosis? (3) What solutions have been proposed to ameliorate these causal factors? (4) Which proposed solutions have been implemented and in which organizational contexts? (5) Have implemented solutions been evaluated and what learning has been generated? Through searches on PubMed, ScienceDirect and LISTA, we included 109 articles. We identified 5 main problem categories: achieving patient engagement, provider engagement, appropriate data governance, security and interoperability, and a sustainable business model. Further, we identified key factors contributing to these problems as well as solutions proposed to ameliorate them. While about half (45) of the 109 articles proposed solutions, fewer than half of these solutions (18) were implemented, and even fewer (5) were evaluated to generate learning about their effects. Few studies systematically report on the patient portal development processes. As a result, the review does not provide an evidence base for portal development. Our findings support a set of recommendations for advancement of the evidence base: future research should build on existing evidence, draw on principles from design sciences conveyed in the problem-solving cycle, and seek to produce evidence within various different organizational contexts. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

What do we know about developing patient portals? a systematic literature review

PubMed Central

de Bont, Antoinette; Rundall, Thomas G; van de Klundert, Joris

2016-01-01

Objective Numerous articles have reported on the development of patient portals, including development problems and solutions. We review these articles to inform future patient portal development efforts and to provide a summary of the evidence base that can guide future research. Materials and Methods We performed a systematic review of relevant literature to answer 5 questions: (1) What categories of problems related to patient portal development have been defined? (2) What causal factors have been identified by problem analysis and diagnosis? (3) What solutions have been proposed to ameliorate these causal factors? (4) Which proposed solutions have been implemented and in which organizational contexts? (5) Have implemented solutions been evaluated and what learning has been generated? Through searches on PubMed, ScienceDirect and LISTA, we included 109 articles. Results We identified 5 main problem categories: achieving patient engagement, provider engagement, appropriate data governance, security and interoperability, and a sustainable business model. Further, we identified key factors contributing to these problems as well as solutions proposed to ameliorate them. While about half (45) of the 109 articles proposed solutions, fewer than half of these solutions (18) were implemented, and even fewer (5) were evaluated to generate learning about their effects. Discussion Few studies systematically report on the patient portal development processes. As a result, the review does not provide an evidence base for portal development. Conclusion Our findings support a set of recommendations for advancement of the evidence base: future research should build on existing evidence, draw on principles from design sciences conveyed in the problem-solving cycle, and seek to produce evidence within various different organizational contexts. PMID:26335985

Sensitivity of emergent sociohydrologic dynamics to internal system properties and external sociopolitical factors: Implications for water management

NASA Astrophysics Data System (ADS)

Elshafei, Y.; Tonts, M.; Sivapalan, M.; Hipsey, M. R.

2016-06-01

It is increasingly acknowledged that effective management of water resources requires a holistic understanding of the coevolving dynamics inherent in the coupled human-hydrology system. One of the fundamental information gaps concerns the sensitivity of coupled system feedbacks to various endogenous system properties and exogenous societal contexts. This paper takes a previously calibrated sociohydrology model and applies an idealized implementation, in order to: (i) explore the sensitivity of emergent dynamics resulting from bidirectional feedbacks to assumptions regarding (a) internal system properties that control the internal dynamics of the coupled system and (b) the external sociopolitical context; and (ii) interpret the results within the context of water resource management decision making. The analysis investigates feedback behavior in three ways, (a) via a global sensitivity analysis on key parameters and assessment of relevant model outputs, (b) through a comparative analysis based on hypothetical placement of the catchment along various points on the international sociopolitical gradient, and (c) by assessing the effects of various direct management intervention scenarios. Results indicate the presence of optimum windows that might offer the greatest positive impact per unit of management effort. Results further advocate management tools that encourage an adaptive learning, community-based approach with respect to water management, which are found to enhance centralized policy measures. This paper demonstrates that it is possible to use a place-based sociohydrology model to make abstractions as to the dynamics of bidirectional feedback behavior, and provide insights as to the efficacy of water management tools under different circumstances.

From repulsion to attraction: species- and spatial context-dependent threat sensitive response of the spider mite Tetranychus urticae to predatory mite cues

NASA Astrophysics Data System (ADS)

Fernández Ferrari, M. Celeste; Schausberger, Peter

2013-06-01

Prey perceiving predation risk commonly change their behavior to avoid predation. However, antipredator strategies are costly. Therefore, according to the threat-sensitive predator avoidance hypothesis, prey should match the intensity of their antipredator behaviors to the degree of threat, which may depend on the predator species and the spatial context. We assessed threat sensitivity of the two-spotted spider mite, Tetranychus urticae, to the cues of three predatory mites, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni, posing different degrees of risk in two spatial contexts. We first conducted a no-choice test measuring oviposition and activity of T. urticae exposed to chemical traces of predators or traces plus predator eggs. Then, we tested the site preference of T. urticae in choice tests, using artificial cages and leaves. In the no-choice test, T. urticae deposited their first egg later in the presence of cues of P. persimilis than of the other two predators and cue absence, indicating interspecific threat-sensitivity. T. urticae laid also fewer eggs in the presence of cues of P. persimilis and A. andersoni than of N. californicus and cue absence. In the artificial cage test, the spider mites preferred the site with predator traces, whereas in the leaf test, they preferentially resided on leaves without traces. We argue that in a nonplant environment, chemical predator traces do not indicate a risk for T. urticae, and instead, these traces function as indirect habitat cues. The spider mites were attracted to these cues because they associated them with the existence of a nearby host plant.

From repulsion to attraction: species- and spatial context-dependent threat sensitive response of the spider mite Tetranychus urticae to predatory mite cues.

PubMed

Fernández Ferrari, M Celeste; Schausberger, Peter

2013-06-01

Prey perceiving predation risk commonly change their behavior to avoid predation. However, antipredator strategies are costly. Therefore, according to the threat-sensitive predator avoidance hypothesis, prey should match the intensity of their antipredator behaviors to the degree of threat, which may depend on the predator species and the spatial context. We assessed threat sensitivity of the two-spotted spider mite, Tetranychus urticae, to the cues of three predatory mites, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni, posing different degrees of risk in two spatial contexts. We first conducted a no-choice test measuring oviposition and activity of T. urticae exposed to chemical traces of predators or traces plus predator eggs. Then, we tested the site preference of T. urticae in choice tests, using artificial cages and leaves. In the no-choice test, T. urticae deposited their first egg later in the presence of cues of P. persimilis than of the other two predators and cue absence, indicating interspecific threat-sensitivity. T. urticae laid also fewer eggs in the presence of cues of P. persimilis and A. andersoni than of N. californicus and cue absence. In the artificial cage test, the spider mites preferred the site with predator traces, whereas in the leaf test, they preferentially resided on leaves without traces. We argue that in a nonplant environment, chemical predator traces do not indicate a risk for T. urticae, and instead, these traces function as indirect habitat cues. The spider mites were attracted to these cues because they associated them with the existence of a nearby host plant.

Context sensitive formulations of antenna pattern correction and side lobe compensation for NOSS/LAMMR real time processing

NASA Technical Reports Server (NTRS)

Chin, R. T.; Beaudet, P. R.

1981-01-01

Large antenna multi-channel microwave radiometer (LAMMR) software specifications were written for LAMMR ground processing. There is a need to determine more computationally-efficient antenna temperature correction methods in compensating side lobe contributions especially near continents, islands and weather fronts. One of the major conclusions was that the antenna pattern corrections (APC) processes did not accomplish the implied goals of compensating for the antenna side lobe influences on brightness temperature. A-priori knowledge of land/water locations was shown to be needed and had to be incorporated in a context sensitive APC process if the artifacts caused by land presence is to be avoided. The high temperatures in land regions can severely bias the lower ocean response.

[Research on optimization of mathematical model of flow injection-hydride generation-atomic fluorescence spectrometry].

PubMed

Cui, Jian; Zhao, Xue-Hong; Wang, Yan; Xiao, Ya-Bing; Jiang, Xue-Hui; Dai, Li

2014-01-01

Flow injection-hydride generation-atomic fluorescence spectrometry was a widely used method in the industries of health, environmental, geological and metallurgical fields for the merit of high sensitivity, wide measurement range and fast analytical speed. However, optimization of this method was too difficult as there exist so many parameters affecting the sensitivity and broadening. Generally, the optimal conditions were sought through several experiments. The present paper proposed a mathematical model between the parameters and sensitivity/broadening coefficients using the law of conservation of mass according to the characteristics of hydride chemical reaction and the composition of the system, which was proved to be accurate as comparing the theoretical simulation and experimental results through the test of arsanilic acid standard solution. Finally, this paper has put a relation map between the parameters and sensitivity/broadening coefficients, and summarized that GLS volume, carrier solution flow rate and sample loop volume were the most factors affecting sensitivity and broadening coefficients. Optimizing these three factors with this relation map, the relative sensitivity was advanced by 2.9 times and relative broadening was reduced by 0.76 times. This model can provide a theoretical guidance for the optimization of the experimental conditions.

Magnetic solutions in Einstein-massive gravity with linear and nonlinear fields

NASA Astrophysics Data System (ADS)

Hendi, Seyed Hossein; Panah, Behzad Eslam; Panahiyan, Shahram; Momennia, Mehrab

2018-06-01

The solutions of U(1) gauge-gravity coupling is one of the interesting models for analyzing the semi-classical nature of spacetime. In this regard, different well-known singular and nonsingular solutions have been taken into account. The paper at hand investigates the geometrical properties of the magnetic solutions by considering Maxwell and power Maxwell invariant (PMI) nonlinear electromagnetic fields in the context of massive gravity. These solutions are free of curvature singularity, but have a conic one which leads to presence of deficit/surplus angle. The emphasize is on modifications that these generalizations impose on deficit angle which determine the total geometrical structure of the solutions, hence, physical/gravitational properties. It will be shown that depending on the background spacetime [being anti de Sitter (AdS) or de Sitter (dS)], these generalizations present different effects and modify the total structure of the solutions differently.

Solute Transfer in Osmotic Dehydration of Vegetable Foods: A Review.

PubMed

Muñiz-Becerá, Sahylin; Méndez-Lagunas, Lilia L; Rodríguez-Ramírez, Juan

2017-10-01

While various mechanisms have been proposed for the water transfer during osmotic dehydration (OD), little progress has been made to understand the mechanisms of solute transfer during osmotic dehydration. The transfer of solutes has been often described only by the diffusion mechanism; however, numerous evidences suggest the participation of a variety of mechanisms. This review deals with the main issues of solute transfer in the OD of vegetables. In this context, several studies suggest that during OD of fruits and vegetables, the migration of solutes is not influenced by diffusion. Thus, new theories that may explain the solute transport are analyzed, considering the influence of the plant microstructure and its interaction with the physicochemical properties of osmotic liquid media. In particular, the surface adhesion phenomenon is analyzed and discussed, as a possible mechanism present during the transfer of solutes in OD. © 2017 Institute of Food Technologists®.

Context-aware workflow management of mobile health applications.

PubMed

Salden, Alfons; Poortinga, Remco

2006-01-01

We propose a medical application management architecture that allows medical (IT) experts readily designing, developing and deploying context-aware mobile health (m-health) applications or services. In particular, we elaborate on how our application workflow management architecture enables chaining, coordinating, composing, and adapting context-sensitive medical application components such that critical Quality of Service (QoS) and Quality of Context (QoC) requirements typical for m-health applications or services can be met. This functional architectural support requires learning modules for distilling application-critical selection of attention and anticipation models. These models will help medical experts constructing and adjusting on-the-fly m-health application workflows and workflow strategies. We illustrate our context-aware workflow management paradigm for a m-health data delivery problem, in which optimal communication network configurations have to be determined.

Revisiting Fluctuations in L2 Article Choice in L1-Korean L2-English Learners

ERIC Educational Resources Information Center

Sarker, Bijon K.; Baek, Seunghyun

2017-01-01

The current study investigated the distinction of L2 (second language) English article choice sensitivity in fifty-three L1-Korean L2-English learners in semantic contexts. In the context of English as a foreign language, the participants were divided into two groups based on grammatical ability as determined by their performance on a cloze test.…

Interleaving Semantic Web Reasoning and Service Discovery to Enforce Context-Sensitive Security and Privacy Policies

DTIC Science & Technology

2005-07-01

policies in pervasive computing environments. In this context, the owner of information sources (e.g. user, sensor, application, or organization...work in decentralized trust management and semantic web technologies . Section 3 introduces an Information Disclosure Agent architecture for...Norman Sadeh July 2005 CMU-ISRI-05-113 School of Computer Science, Carnegie Mellon University 5000 Forbes Avenue, Pittsburgh, PA, 15213

Infants Use Social Context to Bind Actions into a Collaborative Sequence

ERIC Educational Resources Information Center

Fawcett, Christine; Gredebäck, Gustaf

2013-01-01

Eye tracking was used to show that 18-month-old infants are sensitive to social context as a sign that others' actions are bound together as a collaborative sequence based on a joint goal. Infants observed five identical demonstrations in which Actor 1 moved a block to one location and Actor 2 moved the same block to a new location, creating…

Humidity-enhanced sub-ppm sensitivity to ammonia of covalently functionalized single-wall carbon nanotube bundle layers

NASA Astrophysics Data System (ADS)

Rigoni, F.; Freddi, S.; Pagliara, S.; Drera, G.; Sangaletti, L.; Suisse, J.-M.; Bouvet, M.; Malovichko, A. M.; Emelianov, A. V.; Bobrinetskiy, I. I.

2017-06-01

A low-cost method for carbon nanotubes (CNTs) network production from solutions on flexible polyethylene naphthalate substrates has been adopted to prepare high quality and well characterized SWCNT bundle layers to be used as the active layer in chemiresistor gas sensors. Two types of SWCNTs have been tested: pristine SWCNTs, deposited from a surfactant solution, and covalently functionalized SWCNTs, deposited from a dimethyl-acetamide solution. The humidity effects on the sensitivity of the SWCNTs network to NH3 have been investigated. The results show that relative humidity favors the response to NH3, confirming recent theoretical predictions. The COOH-functionalized sample displays the largest response owing to both its hydrophilic nature, favoring the interaction with H2O molecules, and its largest surface area. Compared to data available in the literature, the present sensors display a remarkable sensitivity well below the ppm range, which makes them quite promising for environmental and medical applications, where NH3 concentrations (mostly of the order of tens of ppb) have to be detected.

Ultrafast chemical reactions in shocked nitromethane probed with dynamic ellipsometry and transient absorption spectroscopy.

PubMed

Brown, Kathryn E; McGrane, Shawn D; Bolme, Cynthia A; Moore, David S

2014-04-10

Initiation of the shock driven chemical reactions and detonation of nitromethane (NM) can be sensitized by the addition of a weak base; however, the chemical mechanism by which sensitization occurs remains unclear. We investigated the shock driven chemical reaction in NM and in NM sensitized with diethylenetriamine (DETA), using a sustained 300 ps shock driven by a chirped Ti:sapphire laser. We measured the solutions' visible transient absorption spectra and measured interface particle and shock velocities of the nitromethane solutions using ultrafast dynamic ellipsometry. We found there to be a volume-increasing reaction that takes place around interface particle velocity up = 2.4 km/s and up = 2.2 km/s for neat NM and NM with 5% DETA, respectively. The rate at which transient absorption increases is similar in all mixtures, but with decreasing induction times for solutions with increasing DETA concentrations. This result supports the hypothesis that the chemical reaction mechanisms for shocked NM and NM with DETA are the same. Data from shocked NM are compared to literature experimental and theoretical data.

Factor structure and construct validity of the Anxiety Sensitivity Index among island Puerto Ricans.

PubMed

Cintrón, Jennifer A; Carter, Michele M; Suchday, Sonia; Sbrocco, Tracy; Gray, James

2005-01-01

The factor structure and convergent and discriminant validity of the Anxiety Sensitivity Index (ASI) were examined among a sample of 275 island Puerto Ricans. Results from a confirmatory factor analysis (CFA) comparing our data to factor solutions commonly reported as representative of European American and Spanish populations indicated a poor fit. A subsequent exploratory factor analysis (EFA) indicated that a two-factor solution (Factor 1, Anxiety Sensitivity; Factor 2, Emotional Concerns) provided the best fit. Correlations between the ASI and anxiety measures were moderately high providing evidence of convergent validity, while correlations between the ASI and BDI were significantly lower providing evidence of discriminant validity. Scores on all measures were positively correlated with acculturation, suggesting that those who ascribe to more traditional Hispanic culture report elevated anxiety.

An All-Solid-State pH Sensor Employing Fluorine-Terminated Polycrystalline Boron-Doped Diamond as a pH-Insensitive Solution-Gate Field-Effect Transistor.

PubMed

Shintani, Yukihiro; Kobayashi, Mikinori; Kawarada, Hiroshi

2017-05-05

A fluorine-terminated polycrystalline boron-doped diamond surface is successfully employed as a pH-insensitive SGFET (solution-gate field-effect transistor) for an all-solid-state pH sensor. The fluorinated polycrystalline boron-doped diamond (BDD) channel possesses a pH-insensitivity of less than 3mV/pH compared with a pH-sensitive oxygenated channel. With differential FET (field-effect transistor) sensing, a sensitivity of 27 mv/pH was obtained in the pH range of 2-10; therefore, it demonstrated excellent performance for an all-solid-state pH sensor with a pH-sensitive oxygen-terminated polycrystalline BDD SGFET and a platinum quasi-reference electrode, respectively.

Error analysis applied to several inversion techniques used for the retrieval of middle atmospheric constituents from limb-scanning MM-wave spectroscopic measurements

NASA Technical Reports Server (NTRS)

Puliafito, E.; Bevilacqua, R.; Olivero, J.; Degenhardt, W.

1992-01-01

The formal retrieval error analysis of Rodgers (1990) allows the quantitative determination of such retrieval properties as measurement error sensitivity, resolution, and inversion bias. This technique was applied to five numerical inversion techniques and two nonlinear iterative techniques used for the retrieval of middle atmospheric constituent concentrations from limb-scanning millimeter-wave spectroscopic measurements. It is found that the iterative methods have better vertical resolution, but are slightly more sensitive to measurement error than constrained matrix methods. The iterative methods converge to the exact solution, whereas two of the matrix methods under consideration have an explicit constraint, the sensitivity of the solution to the a priori profile. Tradeoffs of these retrieval characteristics are presented.

Analytical study of robustness of a negative feedback oscillator by multiparameter sensitivity

PubMed Central

2014-01-01

Background One of the distinctive features of biological oscillators such as circadian clocks and cell cycles is robustness which is the ability to resume reliable operation in the face of different types of perturbations. In the previous study, we proposed multiparameter sensitivity (MPS) as an intelligible measure for robustness to fluctuations in kinetic parameters. Analytical solutions directly connect the mechanisms and kinetic parameters to dynamic properties such as period, amplitude and their associated MPSs. Although negative feedback loops are known as common structures to biological oscillators, the analytical solutions have not been presented for a general model of negative feedback oscillators. Results We present the analytical expressions for the period, amplitude and their associated MPSs for a general model of negative feedback oscillators. The analytical solutions are validated by comparing them with numerical solutions. The analytical solutions explicitly show how the dynamic properties depend on the kinetic parameters. The ratio of a threshold to the amplitude has a strong impact on the period MPS. As the ratio approaches to one, the MPS increases, indicating that the period becomes more sensitive to changes in kinetic parameters. We present the first mathematical proof that the distributed time-delay mechanism contributes to making the oscillation period robust to parameter fluctuations. The MPS decreases with an increase in the feedback loop length (i.e., the number of molecular species constituting the feedback loop). Conclusions Since a general model of negative feedback oscillators was employed, the results shown in this paper are expected to be true for many of biological oscillators. This study strongly supports that the hypothesis that phosphorylations of clock proteins contribute to the robustness of circadian rhythms. The analytical solutions give synthetic biologists some clues to design gene oscillators with robust and desired period. PMID:25605374

A comparison of solute-transport solution techniques based on inverse modelling results

USGS Publications Warehouse

Mehl, S.; Hill, M.C.

2000-01-01

Five common numerical techniques (finite difference, predictor-corrector, total-variation-diminishing, method-of-characteristics, and modified-method-of-characteristics) were tested using simulations of a controlled conservative tracer-test experiment through a heterogeneous, two-dimensional sand tank. The experimental facility was constructed using randomly distributed homogeneous blocks of five sand types. This experimental model provides an outstanding opportunity to compare the solution techniques because of the heterogeneous hydraulic conductivity distribution of known structure, and the availability of detailed measurements with which to compare simulated concentrations. The present work uses this opportunity to investigate how three common types of results-simulated breakthrough curves, sensitivity analysis, and calibrated parameter values-change in this heterogeneous situation, given the different methods of simulating solute transport. The results show that simulated peak concentrations, even at very fine grid spacings, varied because of different amounts of numerical dispersion. Sensitivity analysis results were robust in that they were independent of the solution technique. They revealed extreme correlation between hydraulic conductivity and porosity, and that the breakthrough curve data did not provide enough information about the dispersivities to estimate individual values for the five sands. However, estimated hydraulic conductivity values are significantly influenced by both the large possible variations in model dispersion and the amount of numerical dispersion present in the solution technique.Five common numerical techniques (finite difference, predictor-corrector, total-variation-diminishing, method-of-characteristics, and modified-method-of-characteristics) were tested using simulations of a controlled conservative tracer-test experiment through a heterogeneous, two-dimensional sand tank. The experimental facility was constructed using randomly distributed homogeneous blocks of five sand types. This experimental model provides an outstanding opportunity to compare the solution techniques because of the heterogeneous hydraulic conductivity distribution of known structure, and the availability of detailed measurements with which to compare simulated concentrations. The present work uses this opportunity to investigate how three common types of results - simulated breakthrough curves, sensitivity analysis, and calibrated parameter values - change in this heterogeneous situation, given the different methods of simulating solute transport. The results show that simulated peak concentrations, even at very fine grid spacings, varied because of different amounts of numerical dispersion. Sensitivity analysis results were robust in that they were independent of the solution technique. They revealed extreme correlation between hydraulic conductivity and porosity, and that the breakthrough curve data did not provide enough information about the dispersivities to estimate individual values for the five sands. However, estimated hydraulic conductivity values are significantly influenced by both the large possible variations in model dispersion and the amount of numerical dispersion present in the solution technique.

Flip-flop method: A new T1-weighted flow-MRI for plants studies.

PubMed

Buy, Simon; Le Floch, Simon; Tang, Ning; Sidiboulenouar, Rahima; Zanca, Michel; Canadas, Patrick; Nativel, Eric; Cardoso, Maida; Alibert, Eric; Dupont, Guillaume; Ambard, Dominique; Maurel, Christophe; Verdeil, Jean-Luc; Bertin, Nadia; Goze-Bac, Christophe; Coillot, Christophe

2018-01-01

The climate warming implies an increase of stress of plants (drought and torrential rainfall). The understanding of plant behavior, in this context, takes a major importance and sap flow measurement in plants remains a key issue for plant understanding. Magnetic Resonance Imaging (MRI) which is well known to be a powerful tool to access water quantity can be used to measure moving water. We describe a novel flow-MRI method which takes advantage of inflow slice sensitivity. The method involves the slice selectivity in the context of multi slice spin echo sequence. Two sequences such as a given slice is consecutively inflow and outflow sensitive are performed, offering the possiblility to perform slow flow sensitive imaging in a quite straigthforward way. The method potential is demonstrated by imaging both a slow flow measurement on a test bench (as low as 10 μm.s-1) and the Poiseuille's profile of xylemian sap flow velocity in the xylematic tissues of a tomato plant stem.

Bidirectional genetic and environmental influences on mother and child behavior: the family system as the unit of analyses.

PubMed

Mills-Koonce, W Roger; Propper, Cathi B; Gariepy, Jean-Louis; Blair, Clancy; Garrett-Peters, Patricia; Cox, Martha J

2007-01-01

Family systems theory proposes that an individual's functioning depends on interactive processes within the self and within the context of dyadic family subsystems. Previous research on these processes has focused largely on behavioral, cognitive, and psychophysiological properties of the individual and the dyad. The goals of this study were to explore genetic and environmental interactions within the family system by examining how the dopamine receptor D2 gene (DRD2) A1+ polymorphism in mothers and children relates to maternal sensitivity, how maternal and child characteristics might mediate those effects, and whether maternal sensitivity moderates the association between DRD2 A1+ and child affective problems. Evidence is found for an evocative effect of child polymorphism on parenting behavior, and for a moderating effect of child polymorphism on the association between maternal sensitivity and later child affective problems. Findings are discussed from a family systems perspective, highlighting the role of the family as a context for gene expression in both mothers and children.

Perceptual sensitivity to spectral properties of earlier sounds during speech categorization.

PubMed

Stilp, Christian E; Assgari, Ashley A

2018-02-28

Speech perception is heavily influenced by surrounding sounds. When spectral properties differ between earlier (context) and later (target) sounds, this can produce spectral contrast effects (SCEs) that bias perception of later sounds. For example, when context sounds have more energy in low-F 1 frequency regions, listeners report more high-F 1 responses to a target vowel, and vice versa. SCEs have been reported using various approaches for a wide range of stimuli, but most often, large spectral peaks were added to the context to bias speech categorization. This obscures the lower limit of perceptual sensitivity to spectral properties of earlier sounds, i.e., when SCEs begin to bias speech categorization. Listeners categorized vowels (/ɪ/-/ɛ/, Experiment 1) or consonants (/d/-/g/, Experiment 2) following a context sentence with little spectral amplification (+1 to +4 dB) in frequency regions known to produce SCEs. In both experiments, +3 and +4 dB amplification in key frequency regions of the context produced SCEs, but lesser amplification was insufficient to bias performance. This establishes a lower limit of perceptual sensitivity where spectral differences across sounds can bias subsequent speech categorization. These results are consistent with proposed adaptation-based mechanisms that potentially underlie SCEs in auditory perception. Recent sounds can change what speech sounds we hear later. This can occur when the average frequency composition of earlier sounds differs from that of later sounds, biasing how they are perceived. These "spectral contrast effects" are widely observed when sounds' frequency compositions differ substantially. We reveal the lower limit of these effects, as +3 dB amplification of key frequency regions in earlier sounds was enough to bias categorization of the following vowel or consonant sound. Speech categorization being biased by very small spectral differences across sounds suggests that spectral contrast effects occur frequently in everyday speech perception.

The Refinement-Tree Partition for Parallel Solution of Partial Differential Equations

PubMed Central

Mitchell, William F.

1998-01-01

Dynamic load balancing is considered in the context of adaptive multilevel methods for partial differential equations on distributed memory multiprocessors. An approach that periodically repartitions the grid is taken. The important properties of a partitioning algorithm are presented and discussed in this context. A partitioning algorithm based on the refinement tree of the adaptive grid is presented and analyzed in terms of these properties. Theoretical and numerical results are given. PMID:28009355

The Refinement-Tree Partition for Parallel Solution of Partial Differential Equations.

PubMed

Mitchell, William F

1998-01-01

Dynamic load balancing is considered in the context of adaptive multilevel methods for partial differential equations on distributed memory multiprocessors. An approach that periodically repartitions the grid is taken. The important properties of a partitioning algorithm are presented and discussed in this context. A partitioning algorithm based on the refinement tree of the adaptive grid is presented and analyzed in terms of these properties. Theoretical and numerical results are given.

Thermal Degradation and Identification of Heat-Sensitive Polymers

ERIC Educational Resources Information Center

Clough, Stuart C.; Goldman, Emma W.

2005-01-01

A study demonstrates the thermal degradation of two heat-sensitive polymers, namely, polystyrene and poly (methyl methacrylate). The experiment described in the study introduces undergraduate students to polymer structure as well as the application of spectroscopic techniques to the solution of structural problems.