Science.gov

Sample records for enhanced attenuation categories

  1. When Does Fading Enhance Perceptual Category Learning?

    ERIC Educational Resources Information Center

    Pashler, Harold; Mozer, Michael C.

    2013-01-01

    Training that uses exaggerated versions of a stimulus discrimination (fading) has sometimes been found to enhance category learning, mostly in studies involving animals and impaired populations. However, little is known about whether and when fading facilitates learning for typical individuals. This issue was explored in 7 experiments. In…

  2. ENHANCEMENTS TO NATURAL ATTENUATION: SELECTED CASE STUDIES

    SciTech Connect

    Vangelas, K; W. H. Albright, W; E. S. Becvar, E; C. H. Benson, C; T. O. Early, T; E. Hood, E; P. M. Jardine, P; M. Lorah, M; E. Majche, E; D. Major, D; W. J. Waugh, W; G. Wein, G; O. R. West, O

    2007-05-15

    In 2003 the US Department of Energy (DOE) embarked on a project to explore an innovative approach to remediation of subsurface contaminant plumes that focused on introducing mechanisms for augmenting natural attenuation to achieve site closure. Termed enhanced attenuation (EA), this approach has drawn its inspiration from the concept of monitored natural attenuation (MNA).

  3. Prior Knowledge Enhances the Category Dimensionality Effect

    PubMed Central

    Hoffman, Aaron B.; Harris, Harlan D.; Murphy, Gregory L.

    2008-01-01

    A study of the combined influence of prior knowledge and stimulus dimensionality on category learning was conducted. Subjects learned category structures with the same number of necessary dimensions but more or fewer additional redundant dimensions, and with either knowledge-related or knowledge-unrelated features. Minimal-learning models predict that all subjects, regardless of condition, should learn either the same number of dimensions, or else should respond more slowly to each dimension. Despite similar learning rates and response times, subjects learned more features in the high-dimensional than in the low-dimensional condition. Furthermore, prior knowledge interacted with dimensionality, increasing what was learned especially in the high-dimensional case. A second experiment confirmed that the participants did in fact learn more features during the training phase, rather than simply inferring them at test. These effects can be explained by direct associations among features (representing prior knowledge) combined with feedback between features and the category label, as shown by simulations of the knowledge-resonance, or KRES, model of category learning. PMID:18426059

  4. Enhanced Attenuation Technologies: Passive Soil Vapor Extraction

    SciTech Connect

    Vangelas, K.; Looney, B.; Kamath, R.; Adamson, D.; Newell, C.

    2010-03-15

    Passive soil vapor extraction (PSVE) is an enhanced attenuation (EA) approach that removes volatile contaminants from soil. The extraction is driven by natural pressure gradients between the subsurface and atmosphere (Barometric Pumping), or by renewable sources of energy such as wind or solar power (Assisted PSVE). The technology is applicable for remediating sites with low levels of contamination and for transitioning sites from active source technologies such as active soil vapor extraction (ASVE) to natural attenuation. PSVE systems are simple to design and operate and are more cost effective than active systems in many scenarios. Thus, PSVE is often appropriate as an interim-remedial or polishing strategy. Over the past decade, PSVE has been demonstrated in the U.S. and in Europe. These demonstrations provide practical information to assist in selecting, designing and implementing the technology. These demonstrations indicate that the technology can be effective in achieving remedial objectives in a timely fashion. The keys to success include: (1) Application at sites where the residual source quantities, and associated fluxes to groundwater, are relatively low; (2) Selection of the appropriate passive energy source - barometric pumping in cases with a deep vadose zone and barrier (e.g., clay) layers that separate the subsurface from the atmosphere and renewable energy assisted PSVE in other settings and where higher flow rates are required. (3) Provision of sufficient access to the contaminated vadose zones through the spacing and number of extraction wells. This PSVE technology report provides a summary of the relevant technical background, real-world case study performance, key design and cost considerations, and a scenario-based cost evaluation. The key design and cost considerations are organized into a flowchart that dovetails with the Enhanced Attenuation: Chlorinated Organics Guidance of the Interstate Technology and Regulatory Council (ITRC). The PSVE

  5. GROUND WATER REMEDIATION RESEARCH: ENHANCED BIOREMEDIATION AND MONITORED NATURAL ATTENUATION

    EPA Science Inventory

    An overview of ground water remediation research conducted at the Subsurface Protection and Remediation Division is provided. The focus of the overview is on Enhanced Bioremediation and Monitored Natural Attenuation research for the remediation of organic and inorganic contamina...

  6. Monitored natural attenuation and enhanced attenuation for chlorinated solvent plumes - It's all about balance

    USGS Publications Warehouse

    Adams, K.A.; Vangelas, K.M.; Looney, B.B.; Chapelle, F.; Early, T.; Gilmore, T.; Sink, C.H.

    2005-01-01

    Nature's inherent ability to cleanse itself is at the heart of Monitored Natural Attenuation (MNA). The complexity comes when one attempts to measure and calculate this inherent ability, called the Natural Attenuation Capacity (NAC), and determine if it is sufficient to cleanse the system to agreed upon criteria. An approach that is simple in concept for determining whether the NAC is sufficient for MNA to work is the concept of a mass balance. Mass balance is a robust framework upon which all decisions can be made. The inflows to and outflows from the system are balanced against the NAC of the subsurface system. For MNA to be acceptable, the NAC is balanced against the contaminant loading to the subsurface system with the resulting outflow from the system being in a range that is acceptable to the regulating and decision-making parties. When the system is such that the resulting outflow is not within an acceptable range, the idea of taking actions that are sustainable and that will bring the system within the acceptable range of outflows is evaluated. These sustainable enhancements are being developed under the Enhanced Attenuation (EA) concept. Copyright ASCE 2005.

  7. Is discrimination enhanced at the boundaries of perceptual categories? A negative case.

    PubMed

    Danilova, M V; Mollon, J D

    2014-06-22

    The human visual system imposes discrete perceptual categories on the continuous input space that is represented by the ratios of excitations of the cones in the retina. Is discrimination enhanced at the boundaries between perceptual hues, in the way that discrimination may be enhanced at the boundaries between speech sounds in hearing? In the chromaticity diagram, the locus of unique green separates colours that appear yellowish from those that appear bluish. Using a two-alternative spatial forced choice and an adapting field equivalent to the Daylight Illuminant D65, we measured chromatic discrimination along lines orthogonal to the locus of unique green. In experimental runs interleaved with these performance measurements, we obtained estimates of the phenomenological boundary from the same observers. No enhancement of objectively measured discrimination was observed at the category boundary between yellowish and bluish hues. Instead, thresholds were minimal at chromaticities where the ratio of long-wave to middle-wave cone excitation was the same as that for the background adapting field.

  8. Vowel category boundaries enhance cortical and behavioral responses to speech feedback alterations.

    PubMed

    Niziolek, Caroline A; Guenther, Frank H

    2013-07-17

    Auditory feedback is instrumental in the online control of speech, allowing speakers to compare their self-produced speech signal with a desired auditory target and correct for errors. However, there is little account of the representation of "target" and "error": does error depend purely on acoustic distance from a target, or is error enhanced by phoneme category changes? Here, we show an effect of vowel boundaries on compensatory responses to a real-time auditory perturbation. While human subjects spoke monosyllabic words, event-triggered functional magnetic resonance imaging was used to characterize neural responses to unexpected changes in auditory feedback. Capitalizing on speakers' natural variability, we contrasted the responses to feedback perturbations applied to two classes of utterances: (1) those that fell nearer to the category boundary, for which perturbations were designed to change the phonemic identity of the heard speech; and (2) those that fell farther from the boundary, for which perturbations resulted in only sub-phonemic auditory differences. Subjects' behavioral compensation was more than three times greater when feedback shifts were applied nearer to a category boundary. Furthermore, a near-boundary shift resulted in stronger cortical responses, most notably in right posterior superior temporal gyrus, than an identical shift that occurred far from the boundary. Across participants, a correlation was found between the amount of compensation to the perturbation and the amount of activity in a network of superior temporal and inferior frontal brain regions. Together, these results demonstrate that auditory feedback control of speech is sensitive to linguistic categories learned through auditory experience.

  9. Graded lagrangians, exotic topological D-branes and enhanced triangulated categories

    NASA Astrophysics Data System (ADS)

    Lazaroiu, Calin Iuliu

    2001-06-01

    I point out that (BPS saturated) A-type D-branes in superstring compactification on Calabi-Yau threefolds correspond to graded special lagrangian submanifolds, a particular case of the graded lagrangian submanifolds considered by M. Kontsevich and P. Seidel. Combining this with the categorical formulation of cubic string field theory in the presence of D-branes, I consider a collection of topological D-branes wrapped over the same lagrangian cycle and derive its string field action from first string-theoretic principles. The result is a Script Z-graded version of super-Chern-Simons field theory living on the lagrangian cycle, whose relevant string field is a degree one superconnection in a Script Z-graded superbundle, in the sense previously considered in mathematical work of J.M. Bismutt and J. Lott. This gives a refined (and modified) version of a proposal previously made by C. Vafa. I analyze the vacuum deformations of this theory and relate them to topological D-brane composite formation, upon using the general formalism developed in a previous paper. This allows me to identify a large class of topological D-brane composites (generalized, or ``exotic'' topological D-branes) which do not admit a traditional description. Among these are objects which correspond to the ``covariantly constant sequences of flat bundles'' considered by Bismut and Lott, as well as more general structures, which are related to the enhanced triangulated categories of Bondal and Kapranov. I also give a rough sketch of the relation between this construction and the large radius limit of a certain version of the ``derived category of Fukaya's category''. This paper forms part of a joint project with Prof. S. Popescu, a brief announcement of which can be found in the second part of the note hep-th/0102183. The paralel B-model realization, as well as the relation with the enhanced triangulated categories of Bondal and Kapranov, was recently discussed by D.E. Diaconescu in the paper hep

  10. Monitored Natural Attenuation and Enhanced Attenuation for Chlorinated Solvent Plumes - It’s All About Balance

    SciTech Connect

    VANGELAS, KAREN

    2005-05-19

    Nature's inherent ability to cleanse itself is at the heart of Monitored Natural Attenuation (MNA). The complexity comes when one attempts to measure and calculate this inherent ability, called the Natural Attenuation Capacity (NAC), and determine if it is sufficient to cleanse the system to agreed upon criteria. An approach that is simple in concept for determining whether the NAC is sufficient for MNA to work is the concept of a mass balance. Mass balance is a robust framework upon which all decisions can be made. The inflows to and outflows from the system are balanced against the NAC of the subsurface system. For MNA to be acceptable, the NAC is balanced against the contaminant loading to the subsurface system with the resulting outflow from the system being in a range that is acceptable to the regulating and decision-making parties. When the system is such that the resulting outflow is not within an acceptable range, the idea of taking actions that are sustainable and that will bring the system within the acceptable range of outflows is evaluated. These sustainable enhancements are being developed under the Enhanced Attenuation (EA) concept.

  11. Characterization of Small Focal Renal Lesions: Diagnostic Accuracy with Single-Phase Contrast-enhanced Dual-Energy CT with Material Attenuation Analysis Compared with Conventional Attenuation Measurements.

    PubMed

    Marin, Daniele; Davis, Drew; Roy Choudhury, Kingshuk; Patel, Bhavik; Gupta, Rajan T; Mileto, Achille; Nelson, Rendon C

    2017-03-28

    Purpose To determine whether single-phase contrast material-enhanced dual-energy material attenuation analysis improves the characterization of small (1-4 cm) renal lesions compared with conventional attenuation measurements by using histopathologic analysis and follow-up imaging as the clinical reference standards. Materials and Methods In this retrospective, HIPAA-compliant, institutional review board-approved study, 136 consecutive patients (95 men and 41 women; mean age, 54 years) with 144 renal lesions (111 benign, 33 malignant) measuring 1-4 cm underwent single-energy unenhanced and contrast-enhanced dual-energy computed tomography (CT) of the abdomen. For each renal lesion, attenuation measurements were obtained; attenuation change of greater than or equal to 15 HU was considered evidence of enhancement. Dual-energy attenuation measurements were also obtained by using iodine-water, water-iodine, calcium-water, and water-calcium material basis pairs. Mean lesion attenuation values and material densities were compared between benign and malignant renal lesions by using the two-sample t test. Diagnostic accuracy of attenuation measurements and dual-energy material densities was assessed and validated by using 10-fold cross-validation to limit the effect of optimistic bias. Results By using cross-validated optimal thresholds at 100% sensitivity, iodine-water material attenuation images significantly improved specificity for differentiating between benign and malignant renal lesions compared with conventional enhancement measurements (93% [103 of 111]; 95% confidence interval: 86%, 97%; vs 81% [90 of 111]; 95% confidence interval: 73%, 88%) (P = .02). Sensitivity with iodine-water and calcium-water material attenuation images was also higher than that with conventional enhancement measurements, although the difference was not statistically significant. Conclusion Contrast-enhanced dual-energy CT with material attenuation analysis improves specificity for

  12. ADVANCING THE SCIENCE OF NATURAL AND ENHANCED ATTENUATION FOR CHLORINATED SOLVENTS

    SciTech Connect

    Looney, B; TOM O. EARLY, T; TYLER GILMORE, T; FRANCIS H. CHAPELLE, F; NORMAN H. CUTSHALL, N; JEFF ROSS, J; MARK ANKENY, M; Michael Heitkamp, M; DAVID MAJOR, D; CHARLES J. NEWELL, C; W. JODY WAUGH, W; GARY WEIN, G; Karen Vangelas, K; Karen-M Adams, K; CLAIRE H. SINK, C

    2006-12-27

    This report summarizes the results of a three-year program that addressed key scientific and technical aspects related to natural and enhanced attenuation of chlorinated organics. The results from this coordinated three-year program support a variety of technical and regulatory advancements. Scientists, regulators, engineers, end-users and stakeholders participated in the program, which was supported by the U.S. Department of Energy (DOE) and the Interstate Technology and Regulatory Council (ITRC). The overarching objective of the effort was to examine environmental remedies that are based on natural processes--remedies such as Monitored Natural Attenuation (MNA) or Enhanced Attenuation (EA). A key result of the recent effort was the general affirmation of the approaches and guidance in the original U.S. Environmental Protection Agency (EPA) chlorinated solvent MNA protocols and directives from 1998 and 1999, respectively. The research program did identify several specific opportunities for advances based on: (1) mass balance as the central framework for attenuation based remedies, (2) scientific advancements and achievements during the past ten years, (3) regulatory and policy development and real-world experience using MNA, and (4) exploration of various ideas for integrating attenuation remedies into a systematic set of ''combined remedies'' for contaminated sites. These opportunities are summarized herein and are addressed in more detail in referenced project documents and journal articles, as well as in the technical and regulatory documents being developed within the ITRC. Natural attenuation processes occur in all soil and groundwater systems and act, to varying degrees, on all contaminants. Thus, a decision to rely on natural attenuation processes as part of a site-remediation strategy does not depend on the occurrence of natural attenuation, but on its effectiveness in meeting site-specific remediation goals. Meeting these goals typically requires low risk

  13. MASS BALANCE: A KEY TO ADVANCING MONITORED AND ENHANCED ATTENUATION FOR CHLORINATED SOLVENTS

    SciTech Connect

    Looney, B; Karen Vangelas, K; Karen-M Adams, K; Francis H. Chappelle; Tom O. Early; Claire H. Sink

    2006-06-30

    Monitored natural attenuation (MNA) and enhanced attenuation (EA) are two environmental management strategies that rely on a variety of attenuation processes to degrade or immobilize contaminants and are implemented at appropriate sites by demonstrating that contaminant plumes have low risk and are stable or shrinking. The concept of a mass balance between the loading and attenuation of contaminants in a groundwater system is a powerful framework for conceptualizing and documenting the relative stability of a contaminant plume. As a result, this concept has significant potential to support appropriate implementation of monitored natural attenuation (MNA) and enhanced attenuation (EA). For mass balance to be useful in engineering practice, however, it is necessary to quantify it in practical ways that facilitate overall site remediation and which are consistent with existing regulatory guidance. Two divergent philosophies exist for quantifying plume stability--empirical and deterministic. The first relies on historical contaminant concentration data and bulk geochemical information from a monitoring well network and documents plume stability using trend analysis and statistical tools. This empirical approach, when feasible, provides powerful and compelling documentation of plume behavior and mass balance. It provides an interpretation on a relevant scale under field conditions. It integrates the operative attenuation processes measured by observing their actual impact on the plume. The power of the empirical approach was recognized early in the development of MNA guidance and protocols and it is currently the basis of the three lines of evidence used in MNA studies. The empirical approach has some weaknesses, however. It requires a relatively long period of undisturbed historical data. Thus it cannot be effectively applied to sites where active remediation was initiated quickly and is currently operating. It cannot be used as a tool to determine how much source

  14. POTENTIAL ENHANCEMENTS TO NATURAL ATTENUATION: LINES OF INQUIRY SUPPORTING ENHANCED PASSIVE REMEDIATION OF CHLORINATED SOLVENTS

    SciTech Connect

    Vangelas, K; Tom Early, T; Michael Heitkamp, M; Brian02 Looney, B; David Major, D; Brian Riha, B; Jody Waugh, J; Gary Wein, G

    2004-06-18

    The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Passive Remediation (EPR) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA/EPR. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology and Regulatory Council and the U.S. Environmental Protection Agency (EPA). The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision-making throughout the period of the subject MNA/EPR Alternative Project. To support and more fully document the information presented in the summary report, we are publishing a series of supplemental documents that present the full texts from the technical analyses within the various lines of inquiry (see listing). The following report - documenting our evaluation of the state of the science of the characterization and monitoring process and tools-- is one of those supplemental documents.

  15. Multiple Lines Of Evidence Supporting Natural Attenuation: Lines Of Inquiry Supporting Monitored Natural Attenuation And Enhanced Attenuatin Of Chlorinated Solvents

    SciTech Connect

    Vangelas, Karen; Widemeirer, T. H.; Barden, M.J.; Dickson, W. Z.; Major, David

    2004-12-31

    The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Attenuation (EA) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA/EA. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology Regulatory Council (ITRC) and the United States Environmental Protection Agency (USEPA). The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision making throughout the period of the subject MNA/EA Alternative Project. To support and more fully document the information presented in the summary report, the DOE is publishing a series of supplemental documents that present the full texts from the technical analyses within the various lines of inquiry (see listing). The following report--documenting our evaluation of the state of the science for the lines of evidence for supporting decision-making for MNA--is one of those supplemental documents.

  16. ENHANCED ATTENUATION: A REFERENCE GUIDE ON APPROACHES TO INCREASE THE NATURAL TREATMENT CAPACITY OF A SYSTEM

    SciTech Connect

    Looney, B; Michael Heitkamp, M; Gary Wein , G; Karen Vangelas, K; Karen-M Adams, K; Tom Early; Bob Borden; David Major; W. Jody Waugh; Todd Wiedemeier; Claire H. Sink

    2006-08-10

    The objective of this document is to explore the realm of enhancements to natural attenuation processes for cVOCs and review examples that have been proposed, modeled, and implemented. We will identify lessons learned from these case studies to confirm that enhancements are technically feasible and have the potential to achieve a favorable, cost-effective contaminant mass balance. Furthermore, we hope to determine if opportunities for further improvement of the enhancements exist and suggest areas where new and innovative types of enhancements might be possible.

  17. Enhanced Attenuation: A Reference Guide On Approaches To Increase The Natural Treatment Capacity Of A System

    SciTech Connect

    Vangelas, K

    2006-01-30

    The objective of this document is to explore the realm of enhancements to natural attenuation processes for cVOCs and review examples that have been proposed, modeled, and implemented. We will identify lessons learned from these case studies to confirm that enhancements are technically feasible and have the potential to achieve a favorable, cost-effective contaminant mass balance. Furthermore, we hope to determine if opportunities for further improvement of the enhancements exist and suggest areas where new and innovative types of enhancements might be possible.

  18. Contrast enhanced CT attenuation correlates with the GAG content of bovine meniscus.

    PubMed

    Lakin, Bejamin A; Grasso, Daniel J; Stewart, Rachel C; Freedman, Jonathan D; Snyder, Brian D; Grinstaff, Mark W

    2013-11-01

    We determined whether contrast-enhanced computed tomography (CECT) attenuation obtained using a µCT scanner correlated with the glycosaminoglycan (GAG) content and distribution in ex vivo bovine menisci. Bovine samples were immersed in different concentrations of the contrast agents CA4+ and Ioxaglate, and the µCT images were compared to Safranin-O staining. CA4+ and Ioxaglate diffusion-in kinetics and the correlation between their CECT attenuations and GAG content were investigated. CA4+ and Ioxaglate both reached steady state in the meniscal regions within 95 h, with tau values of 20.6 ± 3.98 and 25.9 ± 3.71 h (mean ± SD), respectively. Both agents diffused preferentially through the proximal and secondarily through the distal surface. The CA4+ CECT attenuation was strongly and positively correlated with the GAG content of the meniscus regions (R(2)  = 0.89, p < 0.001) at low concentrations (12 mgI/ml), while the Ioxaglate CECT attenuation was moderately and negatively correlated with the GAG content (R(2)  = 0.51, p = 0.03) at 60 mgI/ml. CECT can image ex vivo menisci, and the CA4+, compared to Ioxaglate, enhanced attenuation strongly correlates with the GAG content and distribution in bovine meniscus.

  19. Enhancement of the safety of live influenza vaccine by attenuating mutations from cold-adapted hemagglutinin

    SciTech Connect

    Lee, Yoon Jae; Jang, Yo Han; Kim, Paul; Lee, Yun Ha; Lee, Young Jae; Byun, Young Ho; Lee, Kwang-Hee; Kim, Kyusik; Seong, Baik Lin

    2016-04-15

    In our previous study, X-31ca-based H5N1 LAIVs, in particular, became more virulent in mice than the X-31ca MDV, possibly by the introduction of the surface antigens of highly pathogenic H5N1 influenza virus, implying that additional attenuation is needed in this cases to increase the safety level of the vaccine. In this report we suggest an approach to further increase the safety of LAIV through additional cold-adapted mutations in the hemagglutinin. The cold-adaptation of X-31 virus resulted in four amino acid mutations in the HA. We generated a panel of 7:1 reassortant viruses each carrying the hemagglutinins with individual single amino acid mutations. We examined their phenotypes and found a major attenuating mutation, N81K. This attenuation marker conferred additional temperature-sensitive and attenuation phenotype to the LAIV. Our data indicate that the cold-adapted mutation in the HA confers additional attenuation to the LAIV strain, without compromising its productivity and immune response. - Highlights: • Cold-adaptation process induced four amino acid mutations in the HA of X-31 virus. • The four mutations in the HA also contributed to attenuation of the X-31ca virus • N81K mutation was the most significant marker for the attenuation of X-31ca virus. • Introduction of N81K mutation into H3N2 LAIV further attenuated the vaccine. • This approach provides a useful guideline for enhancing the safety of the LAIVs.

  20. Proapoptotic protein Bim attenuates estrogen-enhanced survival in lymphangioleiomyomatosis

    PubMed Central

    Li, Chenggang; Li, Na; Liu, Xiaolei; Zhang, Erik Y.; Sun, Yang; Masuda, Kouhei; Li, Jing; Sun, Julia; Morrison, Tasha; Li, Xiangke; Chen, Yuanguang; Wang, Jiang; Karim, Nagla A.; Zhang, Yi; Blenis, John; Reginato, Mauricio J.; Henske, Elizabeth P.; Yu, Jane J.

    2016-01-01

    Lymphangioleiomyomatosis (LAM) is a progressive lung disease that primarily affects young women. Genetic evidence suggests that LAM cells bearing TSC2 mutations migrate to the lungs, proliferate, and cause cystic remodeling. The female predominance indicates that estrogen plays a critical role in LAM pathogenesis, and we have proposed that estrogen promotes LAM cell metastasis by inhibition of anoikis. We report here that estrogen increased LAM patient–derived cells’ resistance to anoikis in vitro, accompanied by decreased accumulation of the proapoptotic protein Bim, an activator of anoikis. The resistance to anoikis was reversed by the proteasome inhibitor, bortezomib. Treatment of LAM patient–derived cells with estrogen plus bortezomib promoted anoikis compared with estrogen alone. Depletion of Bim by siRNA in TSC2-deficient cells resulted in anoikis resistance. Treatment of mice with bortezomib reduced estrogen-promoted lung colonization of TSC2-deficient cells. Importantly, molecular depletion of Bim by siRNA in Tsc2-deficient cells increased lung colonization in a mouse model. Collectively, these data indicate that Bim plays a key role in estrogen-enhanced survival of LAM patient–derived cells under detached conditions that occur with dissemination. Thus, targeting Bim may be a plausible future treatment strategy in patients with LAM. PMID:27882343

  1. Proapoptotic protein Bim attenuates estrogen-enhanced survival in lymphangioleiomyomatosis.

    PubMed

    Li, Chenggang; Li, Na; Liu, Xiaolei; Zhang, Erik Y; Sun, Yang; Masuda, Kouhei; Li, Jing; Sun, Julia; Morrison, Tasha; Li, Xiangke; Chen, Yuanguang; Wang, Jiang; Karim, Nagla A; Zhang, Yi; Blenis, John; Reginato, Mauricio J; Henske, Elizabeth P; Yu, Jane J

    2016-11-17

    Lymphangioleiomyomatosis (LAM) is a progressive lung disease that primarily affects young women. Genetic evidence suggests that LAM cells bearing TSC2 mutations migrate to the lungs, proliferate, and cause cystic remodeling. The female predominance indicates that estrogen plays a critical role in LAM pathogenesis, and we have proposed that estrogen promotes LAM cell metastasis by inhibition of anoikis. We report here that estrogen increased LAM patient-derived cells' resistance to anoikis in vitro, accompanied by decreased accumulation of the proapoptotic protein Bim, an activator of anoikis. The resistance to anoikis was reversed by the proteasome inhibitor, bortezomib. Treatment of LAM patient-derived cells with estrogen plus bortezomib promoted anoikis compared with estrogen alone. Depletion of Bim by siRNA in TSC2-deficient cells resulted in anoikis resistance. Treatment of mice with bortezomib reduced estrogen-promoted lung colonization of TSC2-deficient cells. Importantly, molecular depletion of Bim by siRNA in Tsc2-deficient cells increased lung colonization in a mouse model. Collectively, these data indicate that Bim plays a key role in estrogen-enhanced survival of LAM patient-derived cells under detached conditions that occur with dissemination. Thus, targeting Bim may be a plausible future treatment strategy in patients with LAM.

  2. Enhanced procedural learning of speech sound categories in a genetic variant of FOXP2.

    PubMed

    Chandrasekaran, Bharath; Yi, Han-Gyol; Blanco, Nathaniel J; McGeary, John E; Maddox, W Todd

    2015-05-20

    A mutation of the forkhead box protein P2 (FOXP2) gene is associated with severe deficits in human speech and language acquisition. In rodents, the humanized form of FOXP2 promotes faster switching from declarative to procedural learning strategies when the two learning systems compete. Here, we examined a polymorphism of FOXP2 (rs6980093) in humans (214 adults; 111 females) for associations with non-native speech category learning success. Neurocomputational modeling results showed that individuals with the GG genotype shifted faster to procedural learning strategies, which are optimal for the task. These findings support an adaptive role for the FOXP2 gene in modulating the function of neural learning systems that have a direct bearing on human speech category learning.

  3. Multiband enhanced absorption of monolayer graphene with attenuated total reflectance configuration and sensing application

    NASA Astrophysics Data System (ADS)

    Wang, Nan; Bu, Lingbing; Chen, Yunyun; Zheng, Gaige; Zou, Xiujuan; Xu, Linhua; Wang, Jicheng

    2017-01-01

    An enhanced absorption of monolayer graphene is obtained in a multilayer film-based attenuated total reflectance configuration in the visible wavelength range. The enhanced absorption under transverse magnetic and electric conditions is associated with the excitation of the waveguide mode in the thin-film layer, which is verified by the numerical calculation of field profiles. The obtained results manifest that the model induces a high field enhancement at the graphene-dielectric interface with the resonant angle, which implies potential sensing applications. The magnitude of the figure of merit is found to be three times higher than that of a conventional surface plasmon sensor.

  4. The use of error-category mapping in pharmacokinetic model analysis of dynamic contrast-enhanced MRI data.

    PubMed

    Gill, Andrew B; Anandappa, Gayathri; Patterson, Andrew J; Priest, Andrew N; Graves, Martin J; Janowitz, Tobias; Jodrell, Duncan I; Eisen, Tim; Lomas, David J

    2015-02-01

    This study introduces the use of 'error-category mapping' in the interpretation of pharmacokinetic (PK) model parameter results derived from dynamic contrast-enhanced (DCE-) MRI data. Eleven patients with metastatic renal cell carcinoma were enrolled in a multiparametric study of the treatment effects of bevacizumab. For the purposes of the present analysis, DCE-MRI data from two identical pre-treatment examinations were analysed by application of the extended Tofts model (eTM), using in turn a model arterial input function (AIF), an individually-measured AIF and a sample-average AIF. PK model parameter maps were calculated. Errors in the signal-to-gadolinium concentration ([Gd]) conversion process and the model-fitting process itself were assigned to category codes on a voxel-by-voxel basis, thereby forming a colour-coded 'error-category map' for each imaged slice. These maps were found to be repeatable between patient visits and showed that the eTM converged adequately in the majority of voxels in all the tumours studied. However, the maps also clearly indicated sub-regions of low Gd uptake and of non-convergence of the model in nearly all tumours. The non-physical condition ve ≥ 1 was the most frequently indicated error category and appeared sensitive to the form of AIF used. This simple method for visualisation of errors in DCE-MRI could be used as a routine quality-control technique and also has the potential to reveal otherwise hidden patterns of failure in PK model applications.

  5. Is discrimination enhanced at a category boundary? The case of unique red.

    PubMed

    Danilova, M V; Mollon, J D

    2016-03-01

    Is chromatic discrimination enhanced at the boundary between different hues? In previous studies, we gave a positive answer for the case of the locus of unique blues and yellows, the boundary that divides color space into reddish and greenish hues. But we did not find enhancement at the locus of unique green, the boundary between yellowish and bluish hues. In the present study, we examined discrimination near the locus of unique red. In interleaved experimental runs, we obtained (1) discrimination thresholds using a four-alternative spatial forced choice and (2) phenomenological judgments of the locus of unique red. When measurements were made along lines parallel to the locus of unique blues and yellows in a MacLeod-Boynton diagram, the locus of minimal thresholds coincided approximately with the locus of unique red; however, this was not the case when measurements were made along lines orthogonal to the locus of unique blues and yellows. To account for these and earlier results, we suppose that the neural channel that determines the discrimination threshold will sometimes coincide with the channel that determines the perceptual hue equilibrium and sometimes will not. If a given point in chromaticity space is a unique hue, then it is expected to remain a unique hue independently of the direction in which measurements are made; however, discrimination thresholds almost certainly will depend on different underlying channels when measurements are made in different directions through the same point in chromaticity space.

  6. Enhanced natural attenuation of BTEX in the nitrate-reducing environment by different electron acceptors.

    PubMed

    Zhao, Yongsheng; Qu, Dan; Hou, Zhimin; Zhou, Rui

    2015-01-01

    Enhancing natural attenuation of benzene, toluene, ethylbenzene, and xylene (BTEX) in groundwater is a potential remediation technology. This study focused on selecting appropriate electron acceptors to promote BTEX degradation in a nitrate-reducing environment. Nitrate-reducing soil was obtained from simulated BTEX-contaminated column. Enhancing experiments were conducted in the microcosm with nitrate-reducing material and simulated BTEX-polluted groundwater to investigate the promoting feasibility of adding dissolved oxygen (DO), nitrate, chelated Fe(III), and sulphate as electron acceptors. The concentrations of BTEX, electron acceptors, and their reducing products were measured. The order of promoting BTEX degradation with four electron acceptors was nitrate>sulphate>chelated Fe(III)>DO, and the first-order decay coefficients were 0.0432, 0.0333, 0.0240, and 0.0155, respectively. Nitrate, sulphate, and chelated Fe(III) enhanced attenuation. Nitrate was the most effective electron acceptor under nitrate-reducing conditions. Selecting proper electron acceptor is significant in promoting BTEX degradation according to the biogeochemical characteristics of local underground environment.

  7. Lab-based investigation of enhanced BTEX attenuation driven by groundwater table fluctuation.

    PubMed

    Yang, Y S; Li, Panpan; Zhang, Xi; Li, Mingjie; Lu, Ying; Xu, Bin; Yu, Tong

    2017-02-01

    Groundwater fluctuation is often overlooked and lack of study in the field contaminant hydrogeology. Hydraulic force from fluctuating groundwater tables leads to dissolution and subsequent enhanced advective transport of petroleum (e.g. BTEX) in contaminated subsurface system. A laboratory investigation of effect of the groundwater table fluctuation (GTF) on BTEX transport, taking toluene as a typical compound, in a typical representative model of aquifers subjected to a daily water-table fluctuation was undertaken in this work. Results showed that toluene in effluent degraded significantly with cycles of GTF, and the attenuation rates differed in porous media types with higher value for fine-coarse sand media (13.7 mg L(-1) d(-1)) and lower for fine sand-clay media (2.8 mg L d(-1)). Hydraulic and hydrochemical evidences inferred that toluene attenuation was controlled mainly by flushing effect in the initial GTF cycle stages, followed by dissolution and mixing action in the later stages. Meanwhile, adsorption was found to take effects in toluene behavior throughout the whole GTF process, particularly obvious in fine sand-clay media with its toluene attenuation rate of only 2.8 mg L d(-1).

  8. SU-E-T-151: Enhanced Radiation Attenuation with Multi-Layer Foils

    SciTech Connect

    Warmington, L; Watanabe, Y

    2014-06-01

    Purpose: To evaluate the effect of increasing the number of thin high Z foils on the dose enhancement and the overall radiation attenuation with a 24MV photon beam. Methods: DOSXYZnrc was used to perform Monte Carlo simulations of multi-layer lead foil configurations. The foil size was 7cm x 7cm. and the foil thickness was adjusted to give a combined thickness of 1mm. The number of foils used was 4, 6, 8, and 10. The separation between foils was also varied from 3 to 9 mm. The Mohan 24MV energy spectrum was used as a photon source. The field size was 5cm x 5cm and SSD was 100 cm. The phantom size was 16cm × 16cm × 28cm. The number of histories ranged from 1 to 2 billion. The percentage difference of the dose between the medium with foils and the homogeneous water was computed along the beam axis. The minimum dose enhancement and the change of integrated dose between the foils were determined. Results: Increasing the number of foils resulted in a decrease in the minimum dose enhancement. The highest dose region occurred in the last section for the 4 and 6 foil cases, whereas the 8 and 10 foil configurations showed the maximum dose region towards the center of the foil group. Increasing the number of foils increased the total integrated dose between foils. For example, the total integrated dose increase between the first and the last foils with a 3mm foil separation were 34.2, 43.4, 57.4, and 64.7% for 4, 6, 8 and 10 foils, respectively. Conclusion: This work showed the degree of dose enhancement around multiple thin lead foils. The results suggest that the total attenuation of photon beam can be increased by increasing the number of foils with a fixed total foil thickness.

  9. The metabolic enhancer piracetam attenuates mitochondrion-specific endonuclease G translocation and oxidative DNA fragmentation.

    PubMed

    Gupta, Sonam; Verma, Dinesh Kumar; Biswas, Joyshree; Rama Raju, K Siva; Joshi, Neeraj; Wahajuddin; Singh, Sarika

    2014-08-01

    This study was performed to investigate the involvement of mitochondrion-specific endonuclease G in piracetam (P)-induced protective mechanisms. Studies have shown the antiapoptotic effects of piracetam but the mechanism of action of piracetam is still an enigma. To assess the involvement of endonuclease G in piracetam-induced protective effects, astrocyte glial cells were treated with lipopolysaccharide (LPS) and piracetam. LPS treatment caused significantly decreased viability, mitochondrial activity, oxidative stress, chromatin condensation, and DNA fragmentation, which were attenuated by piracetam cotreatment. Cotreatment of astrocytes with piracetam showed its significantly time-dependent absorption as observed with high-performance liquid chromatography. Astrocytes treated with piracetam alone showed enhanced mitochondrial membrane potential (MMP) in comparison to control astrocytes. However, in LPS-treated cells no significant alteration in MMP was observed in comparison to control cells. Protein and mRNA levels of the terminal executor of the caspase-mediated pathway, caspase-3, were not altered significantly in LPS or LPS + piracetam-treated astrocytes, whereas endonuclease G was significantly translocated to the nucleus in LPS-treated astrocytes. Piracetam cotreatment attenuated the LPS-induced endonuclease G translocation. In conclusion this study indicates that LPS treatment of astrocytes caused decreased viability, oxidative stress, mitochondrial dysfunction, chromatin condensation, DNA damage, and translocation of endonuclease G to the nucleus, which was inhibited by piracetam cotreatment, confirming that the mitochondrion-specific endonuclease G is one of the factors involved in piracetam-induced protective mechanisms.

  10. Pulsed gas injection: a minimum effort approach for enhanced natural attenuation of chlorobenzene in contaminated groundwater.

    PubMed

    Balcke, Gerd Ulrich; Paschke, Heidrun; Vogt, Carsten; Schirmer, Mario

    2009-07-01

    Chlorobenzene-contaminated groundwater was used to assess pulsed gas sparging as a minimum effort aeration strategy to enhance intrinsic natural attenuation. In contrast to existing biosparging operations, oxygen was supplied at minimum rate by reducing the gas injection frequency to 0.33 day(-1). Field tests in a model aquifer were conducted in a 12 m long reactor, filled with indigenous aquifer material and continuously recharged with polluted groundwater over 3 years. The closed arrangement allowed yield balances, cost accounting as well as the investigation of spatial distributions of parameters which are sensitive to the biodegradation process. Depending on the injection frequency and on the gas chosen for injection (pure oxygen or air) oxygen-deficient conditions prevailed in the aquifer. Despite the limiting availability of dissolved oxygen in the groundwater, chlorobenzene degradation under oxygen-deficient conditions proved to be more effective than under conditions with dissolved oxygen being available in high concentrations.

  11. The role of clay in enhancing attenuation of trace organic contaminants during managed aquifer recharge

    NASA Astrophysics Data System (ADS)

    Regnery, J.; Strasser, A.; Hake, E.; Wing, A.; Drewes, J. E.

    2013-12-01

    For more hydrophobic trace organic contaminants present in surface water or reclaimed water applied for managed aquifer recharge (MAR), sorption onto organic matter can play a major role in attenuation in subsurface systems as the retardation allows more time for biotransformation. In case of low organic matter, other sorptive processes such as interactions with mineral surfaces gain importance. Especially for positively charged molecules, sorption onto clay materials by cation exchange will play a significant role. However, if the cation exchange capacity is limited or sorption of trace organic contaminants to clay materials is reversible due to changes in geochemical conditions (i.e., pH, ion strength), this might not provide a sustainable removal pathway. The objective of this study is to investigate how sorption to clay can enhance the removal of trace organic contaminants during MAR with the goal of evaluating the feasibility (i.e., infiltration capacity) and benefit (i.e., retardation of recalcitrant compounds) of introducing clay materials as reactive barriers in MAR systems. Laboratory-scale soil column experiments and batch sorption experiments using well characterized soil mixtures with different clay percentages under abiotic conditions and spiked at environmentally relevant concentration levels were conducted to derive soil water distribution coefficients for a suite of 15 trace organic chemicals (i.e., pharmaceutical residues, personal care products, household chemicals) and to quantify their sorption/desorption potential. All clay materials used in this study were characterized by X-ray diffraction to obtain information regarding their sorption processes. Furthermore, results were compared with geochemical field data from a full-scale MAR site in Colorado where significant amounts of clay in the subsurface were present. Preliminary results indicated that certain clay materials bear a great potential to retain moderately hydrophobic compounds such as

  12. L-Ascorbate attenuates methamphetamine neurotoxicity through enhancing the induction of endogenous heme oxygenase-1

    SciTech Connect

    Huang, Ya-Ni; Wang, Jiz-Yuh; Lee, Ching-Tien; Lin, Chih-Hung; Lai, Chien-Cheng; Wang, Jia-Yi

    2012-12-01

    Methamphetamine (METH) is a drug of abuse which causes neurotoxicity and increased risk of developing neurodegenerative diseases. We previously found that METH induces heme oxygenase (HO)-1 expression in neurons and glial cells, and this offers partial protection against METH toxicity. In this study, we investigated the effects of L-ascorbate (vitamin C, Vit. C) on METH toxicity and HO-1 expression in neuronal/glial cocultures. Cell viability and damage were evaluated by 3-(4,5-dimethylthianol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) reduction and lactate dehydrogenase (LDH) release, respectively. Neuronal and glial localization of HO-1 were identified by double immunofluorescence staining. Reactive oxygen species (ROS) production was measured using the fluorochrome 2′,7′-dichlorofluorescin diacetate. HO-1 mRNA and protein expression were examined by RT-qPCR and Western blotting, respectively. Results show that Vit. C induced HO-1 mRNA and protein expressions in time- and concentration-dependent manners. Inhibition of p38 mitogen-activated protein kinase (MAPK) but not extracellular signal-regulated kinase (ERK) significantly blocked induction of HO-1 by Vit. C. HO-1 mRNA and protein expressions were significantly elevated by a combination of Vit. C and METH, compared to either Vit. C or METH alone. Pretreatment with Vit. C enhanced METH-induced HO-1 expression and attenuated METH-induced ROS production and neurotoxicity. Pharmacological inhibition of HO activity abolished suppressive effects of Vit. C on METH-induced ROS production and attenuated neurotoxicity. We conclude that induction of HO-1 expression contributes to the attenuation of METH-induced ROS production and neurotoxicity by Vit. C. We suggest that HO-1 induction by Vit. C may serve as a strategy to alleviate METH neurotoxicity. -- Highlights: ► Besides the anti-oxidant effect, Vit. C also induces HO-1 expression in brain cells. ► Vit. C reduces METH neurotoxicity and ROS production by

  13. Categorial Grammars.

    ERIC Educational Resources Information Center

    Wood, Mary McGee; Hudson, Richard, Ed.

    Written as an objective critical assessment, this book is the first linguistic theory guide to categorial grammars. Categorial grammars offer a radical alternative to the phrase-structure paradigm, with roots in the philosophy of language, logic, and algebra. Their historical evolution is outlined and their formal basis is discussed, beginning…

  14. TH-C-204-02: Improving Manuscript Quality Via Structured Reviews, Enhanced Scientific Category Taxonomy, and Outreach.

    PubMed

    Das, S

    2016-06-01

    timely topics and solicit high profile authors to submit review manuscripts. To submit an article, authors will need to work with an assigned Co-Editor to develop a mutually acceptable outline and abstract. 5) A new and exciting class of articles: Medical Physics Dataset Articles (MPDAs) MPDAs describe scientifically or clinically valuable open-access datasets with high potential for contributing to the research of medical physicists working on related problems. In contrast to Research Articles, MPDAs should not include hypothesis testing; or data analyses supporting generalizable conclusions. The publically accessible dataset must be permanently archived before the MPDA can be published. This initiative is being led by Joe Deasy. Update on new publisher transition: The transition of AAPM scientific publishing operations to a major publishing house is a major opportunity to expand Medical Physics readership and its scholarly impact. The advantages include: (a) common manuscript management and web hosting platforms for Medical Physics and its sister journal, JACMP; (b) greater than 4-fold expansion of subscribing institutions; and (c) resources to mount data-driven, highly targeted marketing campaigns to enhance citation and download rates. A transition update of this epochal development, which has only begun as of this writing (3/31/16), will be given. Improving manuscript quality via structured reviews, enhanced scientific category taxonomy, and outreach: Shiva Das, Therapy Physics Editor Medical Physics is committed to continuous improvement with the ultimate goal of improving the potential impact of accepted manuscripts. In order to do so, Medical Physics must be able to tap into important/emerging areas and be able to select high quality contributions consistently via discerning reviews. Improving the quality of reviews is crucial to selecting high quality manuscripts and also to improving manuscript impact via feedback in the review process. With this in mind

  15. IL-33 targeting attenuates intestinal mucositis and enhances effective tumor chemotherapy in mice.

    PubMed

    Guabiraba, R; Besnard, A G; Menezes, G B; Secher, T; Jabir, M S; Amaral, S S; Braun, H; Lima-Junior, R C P; Ribeiro, R A; Cunha, F Q; Teixeira, M M; Beyaert, R; Graham, G J; Liew, F Y

    2014-09-01

    Intestinal damage and severe diarrhea are serious side effects of cancer chemotherapy and constrain the usage of most such therapies. Here we show that interleukin-33 (IL-33) mediates the severe intestinal mucositis in mice treated with irinotecan (CPT-11), a commonly used cancer chemotherapeutic agent. Systemic CPT-11 administration led to severe mucosal damage, diarrhea, and body weight loss concomitant with the induction of IL-33 in the small intestine (SI). This mucositis was markedly reduced in mice deficient in the IL-33R (ST2(-/-)). Moreover, recombinant IL-33 exacerbated the CPT-11-induced mucositis, whereas IL-33 blockade with anti-IL-33 antibody or soluble ST2 markedly attenuated the disease. CPT-11 treatment increased neutrophil accumulation in the SI and adhesion to mesenteric veins. Supernatants from SI explants treated with CPT-11 enhanced transmigration of neutrophils in vitro in an IL-33-, CXCL1/2-, and CXCR2-dependent manner. Importantly, IL-33 blockade reduced mucositis and enabled prolonged CPT-11 treatment of ectopic CT26 colon carcinoma, leading to a beneficial outcome of the chemotherapy. These results suggest that inhibition of the IL-33/ST2 pathway may represent a novel approach to limit mucositis and thus improve the effectiveness of chemotherapy.

  16. Quercetin Attenuates Chronic Ethanol-Induced Hepatic Mitochondrial Damage through Enhanced Mitophagy

    PubMed Central

    Yu, Xiao; Xu, Yanyan; Zhang, Shanshan; Sun, Jian; Liu, Peiyi; Xiao, Lin; Tang, Yuhan; Liu, Liegang; Yao, Ping

    2016-01-01

    Emerging evidence suggested mitophagy activation mitigates ethanol-induced liver injury. However, the effect of ethanol on mitophagy is inconsistent. Importantly, the understanding of mitophagy status after chronic ethanol consumption is limited. This study evaluated the effect of quercetin, a naturally-occurring flavonoid, on chronic ethanol-induced mitochondrial damage focused on mitophagy. An ethanol regime to mice for 15 weeks (accounting for 30% of total calories) led to significant mitochondrial damage as evidenced by changes of the mitochondrial ultrastructure, loss of mitochondrial membrane potential and remodeling of membrane lipid composition, which was greatly attenuated by quercetin (100 mg/kg.bw). Moreover, quercetin blocked chronic ethanol-induced mitophagy suppression as denoted by mitophagosomes-lysosome fusion and mitophagy-related regulator elements, including LC3II, Parkin, p62 and voltage-dependent anion channel 1 (VDAC1), paralleling with increased FoxO3a nuclear translocation. AMP-activated protein kinase (AMPK) and extracellular signal regulated kinase 2 (ERK2), instead of AKT and Sirtuin 1, were involved in quercetin-mediated mitophagy activation. Quercetin alleviated ethanol-elicited mitochondrial damage through enhancing mitophagy, highlighting a promising preventive strategy for alcoholic liver disease. PMID:26742072

  17. Quercetin Attenuates Chronic Ethanol-Induced Hepatic Mitochondrial Damage through Enhanced Mitophagy.

    PubMed

    Yu, Xiao; Xu, Yanyan; Zhang, Shanshan; Sun, Jian; Liu, Peiyi; Xiao, Lin; Tang, Yuhan; Liu, Liegang; Yao, Ping

    2016-01-05

    Emerging evidence suggested mitophagy activation mitigates ethanol-induced liver injury. However, the effect of ethanol on mitophagy is inconsistent. Importantly, the understanding of mitophagy status after chronic ethanol consumption is limited. This study evaluated the effect of quercetin, a naturally-occurring flavonoid, on chronic ethanol-induced mitochondrial damage focused on mitophagy. An ethanol regime to mice for 15 weeks (accounting for 30% of total calories) led to significant mitochondrial damage as evidenced by changes of the mitochondrial ultrastructure, loss of mitochondrial membrane potential and remodeling of membrane lipid composition, which was greatly attenuated by quercetin (100 mg/kg.bw). Moreover, quercetin blocked chronic ethanol-induced mitophagy suppression as denoted by mitophagosomes-lysosome fusion and mitophagy-related regulator elements, including LC3II, Parkin, p62 and voltage-dependent anion channel 1 (VDAC1), paralleling with increased FoxO3a nuclear translocation. AMP-activated protein kinase (AMPK) and extracellular signal regulated kinase 2 (ERK2), instead of AKT and Sirtuin 1, were involved in quercetin-mediated mitophagy activation. Quercetin alleviated ethanol-elicited mitochondrial damage through enhancing mitophagy, highlighting a promising preventive strategy for alcoholic liver disease.

  18. Implementation of Enhanced Attenuation at the DOE Mound Site OU-1 Landfill: Accelerating Progress and Reducing Costs

    SciTech Connect

    Hooten, Gwendolyn; Cato, Rebecca; Looney, Brian

    2016-03-06

    At the US Department of Energy (DOE), Office of Legacy Management, Mound, Ohio, Site, chlorinated organic contaminants (cVOCs) originating from the former solid-waste landfill have impacted groundwater in Operable Unit 1 (OU-1). The baseline groundwater remedy was groundwater pump and treat (P&T). Since the source materials have been removed from the landfill, the Mound core team, which consists of DOE, US Environmental Protection Agency (US EPA), Ohio EPA, and other stakeholders, is assessing the feasibility of switching from the active P&T remedy to a passive attenuation-based remedy. Toward this end, an enhanced attenuation (EA) strategy based on the creation of structured geochemical zones was developed. This EA strategy addresses the residual areas of elevated cVOCs in soil and groundwater while minimizing the rebound of groundwater concentrations above regulatory targets (e.g., maximum contaminant levels [MCLs]) and avoiding plume expansion while the P&T system is turned off. The EA strategy has improved confidence and reduced risk on the OU-1 groundwater transition path to monitored natural attenuation (MNA). To better evaluate the EA strategy, DOE is conducting a field demonstration to evaluate the use of edible oils to enhance the natural attenuation processes. The field demonstration is designed to determine whether structured geochemical zones can be established that expedite the attenuation of cVOCs in the OU-1 groundwater. The EA approach at OU-1 was designed based on “structured geochemical zones” and relies on groundwater flow through a succession of anaerobic and aerobic zones. The anaerobic zones stimulate relatively rapid degradation of the original solvent source compounds (e.g., cVOCs such as tetrachloroethene [PCE] and trichloroethene [TCE]). The surrounding aerobic areas encourage relatively rapid degradation of daughter products (such as dichloroethene [DCE] and vinyl chloride [VC]) as well as enhanced cometabolism of TCE resulting from

  19. MOVING BEYOND PUMP AND TREAT TOWARD ENHANCED ATTENUATION AND COMBINED REMEDIES T-AREA, SAVANNAH RIVER SITE

    SciTech Connect

    Looney, B; Brian Riha, B; Warren Hyde, W; Jay Noonkester, J; Gerald Blount, G

    2008-04-03

    Groundwater beneath T-Area, a former laboratory and semiworks operation at the Department of Energy (DOE) Savannah River Site, is contaminated by chlorinated solvents (cVOCs). Since the contamination was detected in the 1980s, the cVOCs at T-Area have been treated by a combination of soil vapor extraction and groundwater pump and treat. The site has received approval to discontinue the active treatments and implement a full scale test of enhanced attenuation--an engineering and regulatory strategy that has recently been developed by DOE and the Interstate Technology and Regulatory Council. Enhanced attenuation uses active engineering solutions to alter the target site in such a way that the contaminant plume will passively stabilize and shrink and to document that the action will be effective, timely, and sustainable. The paradigm recognizes that attenuation remedies are fundamentally based on a mass balance. Thus, long-term plume dynamics can be altered either by reducing the contaminant loading from the source or by increasing the rate of natural attenuation processes within all, or part of, the plume volume. The combination of technologies that emerged for T-Area included: (1) neat (pure) vegetable oil deployment in the deep vadose zone in the former source area, (2) emulsified vegetable oil deployment within the footprint of the groundwater plume, and (3) identification of attenuation mechanisms and rates for the distal portion of the plume. In the first part, neat oil spreads laterally forming a thin layer on the water table to intercept and reduce future cVOC loading (via partitioning) and reduce oxygen inputs (via biostimulation). In the second and third parts, emulsified oil forms active bioremediation reactor zones within the plume footprint to degrade existing groundwater contamination (via reductive dechlorination) and stimulates long-term attenuation capacity in the distal plume (via cometabolism). For T-Area, the enhanced attenuation development

  20. "Enhanced" Ray Tracing Study of the Attenuation Lanes in Jupiter's Hectometric Radio Emission By Using Cassini Jupiter Encounter Data

    NASA Astrophysics Data System (ADS)

    Imai, M.; Lecacheux, A.

    2014-12-01

    Cassini Jupiter encounter, in the late 2000 and the early 2001, revealed persistent properties of Jovian hectometric (HOM) radiation, which is produced along auroral magnetic field lines in the polar regions of Jupiter. One of the unique properties - known as attenuation lanes (or so-called attenuation bands) - appears as a recurrent, well defined intensity extinction/enhancement feature in the HOM dynamic spectrum. It is believed that this phenomenon is the consequence of ray refraction from high-density medium - either (1) the field-aligned enhanced density along Io plasma torus or (2) Io plasma torus itself or both - in the course of radio propagation from the radio source to the observer. Many studies, mainly on case (1), have used standard ray-tracing technique, which cannot provide reliable information on transmitted radiation intensity. In this study, we have investigated case (2) by using an "enhanced" ray-tracing technique, in which a family of neighboring rays is simultaneously traced, allowing the physical intensity to be estimated along the ray path. We show the results of our ray-tracing computations and then suggest the most plausible scenario for the attenuation lanes phenomenon. More generally and from this example, we conclude that existing refracting plasma structures, encountered by radiation along its ray path through the planetary magnetosphere, might strongly affect, while not taken into account, the overall properties of the radio emission measured by a distant observer.

  1. Importance of Contrast-Enhanced Fluid-Attenuated Inversion Recovery Magnetic Resonance Imaging in Various Intracranial Pathologic Conditions

    PubMed Central

    Lee, Eun Kyoung; Kim, Sungwon; Lee, Yong Seok

    2016-01-01

    Intracranial lesions may show contrast enhancement through various mechanisms that are closely associated with the disease process. The preferred magnetic resonance sequence in contrast imaging is T1-weighted imaging (T1WI) at most institutions. However, lesion enhancement is occasionally inconspicuous on T1WI. Although fluid-attenuated inversion recovery (FLAIR) sequences are commonly considered as T2-weighted imaging with dark cerebrospinal fluid, they also show mild T1-weighted contrast, which is responsible for the contrast enhancement. For several years, FLAIR imaging has been successfully incorporated as a routine sequence at our institution for contrast-enhanced (CE) brain imaging in detecting various intracranial diseases. In this pictorial essay, we describe and illustrate the diagnostic importance of CE-FLAIR imaging in various intracranial pathologic conditions. PMID:26798225

  2. Metabolic enhancer piracetam attenuates rotenone induced oxidative stress: a study in different rat brain regions.

    PubMed

    Verma, Dinesh Kumar; Joshi, Neeraj; Raju, Kunumuri Sivarama; Wahajuddin, Muhammad; Singh, Rama Kant; Singh, Sarika

    2015-01-01

    Piracetam is clinically being used nootropic drug but the details of its neuroprotective mechanism are not well studied. The present study was conducted to assess the effects of piracetam on rotenone induced oxidative stress by using both ex vivo and in vivo test systems. Rats were treated with piracetam (600 mg/kg b.w. oral) for seven constitutive days prior to rotenone administration (intracerebroventricular, 12 µg) in rat brain. Rotenone induced oxidative stress was assessed after 1 h and 24 h of rotenone administration. Ex vivo estimations were performed by using two experimental designs. In one experimental design the rat brain homogenate was treated with rotenone (1 mM, 2 mM and 4 mM) and rotenone+piracetam (10 mM) for 1 h. While in second experimental design the rats were pretreated with piracetam for seven consecutive days. On eighth day the rats were sacrificed, brain homogenate was prepared and treated with rotenone (1 mM, 2 mM and 4mM) for 1h. After treatment the glutathione (GSH) and malondialdehyde (MDA) levels were estimated in brain homogenate. In vivo study showed that pretreatment of piracetam offered significant protection against rotenone induced decreased GSH and increased MDA level though the protection was region specific. But the co-treatment of piracetam with rotenone did not offer significant protection against rotenone induced oxidative stress in ex vivo study. Whereas ex vivo experiments in rat brain homogenate of piracetam pretreated rats, showed the significant protection against rotenone induced oxidative stress. Findings indicated that pretreatment of piracetam significantly attenuated the rotenone induced oxidative stress though the protection was region specific. Piracetam treatment to rats led to its absorption and accumulation in different brain regions as assessed by liquid chromatography mass spectrometry/mass spectrometry. In conclusion, study indicates the piracetam is able to enhance the antioxidant capacity in brain cells

  3. Enhancement of extinction learning attenuates ethanol-seeking behavior and alters plasticity in the prefrontal cortex.

    PubMed

    Gass, Justin T; Trantham-Davidson, Heather; Kassab, Amanda S; Glen, William B; Olive, M Foster; Chandler, L Judson

    2014-05-28

    Addiction is a chronic relapsing disorder in which relapse is often initiated by exposure to drug-related cues. The present study examined the effects of mGluR5 activation on extinction of ethanol-cue-maintained responding, relapse-like behavior, and neuronal plasticity. Rats were trained to self-administer ethanol and then exposed to extinction training during which they were administered either vehicle or the mGluR5 positive allosteric modulator 3-cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl) or CDPPB. CDPPB treatment reduced active lever responding during extinction, decreased the total number of extinction sessions required to meet criteria, and attenuated cue-induced reinstatement of ethanol seeking. CDPPB facilitation of extinction was blocked by the local infusion of the mGluR5 antagonist 3-((2-methyl-4-thiazolyl)ethynyl) pyridine into the infralimbic (IfL) cortex, but had no effect when infused into the prelimbic (PrL) cortex. Analysis of dendritic spines revealed alterations in structural plasticity, whereas electrophysiological recordings demonstrated differential alterations in glutamatergic neurotransmission in the PrL and IfL cortex. Extinction was associated with increased amplitude of evoked synaptic PrL and IfL NMDA currents but reduced amplitude of PrL AMPA currents. Treatment with CDPPB prevented the extinction-induced enhancement of NMDA currents in PrL without affecting NMDA currents in the IfL. Whereas CDPPB treatment did not alter the amplitude of PrL or IfL AMPA currents, it did promote the expression of IfL calcium-permeable GluR2-lacking receptors in both abstinence- and extinction-trained rats, but had no effect in ethanol-naive rats. These results confirm changes in the PrL and IfL cortex in glutamatergic neurotransmission during extinction learning and demonstrate that manipulation of mGluR5 facilitates extinction of ethanol cues in association with neuronal plasticity.

  4. Pre- and post-exposure safety and efficacy of attenuated rabies virus vaccines are enhanced by their expression of IFNγ

    SciTech Connect

    Barkhouse, Darryll A.; Faber, Milosz; Hooper, D. Craig

    2015-01-01

    Consistent with evidence of a strong correlation between interferon gamma (IFNγ) production and rabies virus (RABV) clearance from the CNS, we recently demonstrated that engineering a pathogenic RABV to express IFNγ highly attenuates the virus. Reasoning that IFNγ expression by RABV vaccines would enhance their safety and efficacy, we reverse-engineered two proven vaccine vectors, GAS and GASGAS, to express murine IFNγ. Mortality and morbidity were monitored during suckling mice infection, immunize/challenge experiments and mixed intracranial infections. We demonstrate that GASγ and GASγGAS are significantly attenuated in suckling mice compared to the GASGAS vaccine. GASγ better protects mice from lethal DRV4 RABV infection in both pre- and post-exposure experiments compared to GASGAS. Finally, GASγGAS reduces post-infection neurological sequelae, compared to control, during mixed intracranial infection with DRV4. These data show IFNγ expression by a vaccine vector can enhance its safety while increasing its efficacy as pre- and post-exposure treatment. - Highlights: • IFNγ expression improves attenuated rabies virus safety and immunogenicity. • IFNγ expression is safer and more immunogenic than doubling glycoprotein expression. • Co-infection with IFNγ-expressing RABV prevents wild-type rabies virus lethality. • Vaccine safety and efficacy is additive for IFNγ and double glycoprotein expression.

  5. NEUROTROPHIN RECEPTOR BLOCKADE ATTENUATES DIESEL EXHAUST PARTICULATE MATTER (DEP) ENHANCEMENT OF ALLERGIC RESPONSES

    EPA Science Inventory

    ABSTRACT BODY:
    Recent investigations have linked neurotrophins including NGF, NT-3, and BDNF to allergic airways diseases. Antibody blockade of NGF attenuates airway resistance associated with allergic airway responses in mice. Mice administered an antibody against the low aff...

  6. TREATABILITY STUDY FOR EDIBLE OIL DEPLOYMENT FOR ENHANCED CVOC ATTENUATION FOR T-AREA, SAVANNAH RIVER SITE

    SciTech Connect

    Riha, B.; Looney, B.; Noonkester, J.; Hyde, W.; Walker, R.

    2012-05-15

    Groundwater beneath T-Area, a former laboratory and semiworks operation at the Department of Energy (DOE) Savannah River Site (SRS), is contaminated by chlorinated solvents (cVOCs). Since the contamination was detected in the 1980s, the cVOCs at T-Area have been treated by a combination of soil vapor extraction and groundwater pump and treat. The site received approval to temporarily discontinue the active groundwater treatment and implement a treatability study of enhanced attenuation - an engineering and regulatory strategy that has recently been developed by DOE and the Interstate Technology and Regulatory Council (ITRC 2007). Enhanced attenuation uses active engineering solutions to alter the target site in such a way that the contaminant plume will passively stabilize and shrink and to document that the action will be effective, timely, and sustainable. The paradigm recognizes that attenuation remedies are fundamentally based on a mass balance. Thus, long-term plume dynamics can be altered either by reducing the contaminant loading from the source or by increasing the rate of natural attenuation processes within all, or part of, the plume volume. The combination of technologies that emerged for T-Area included: (1) neat (pure) vegetable oil deployment in the deep vadose zone in the former source area, (2) emulsified vegetable oil deployment within the footprint of the groundwater plume, and (3) identification of attenuation mechanisms and rates for the distal portion of the plume. In the first part, neat oil spreads laterally forming a thin layer on the water table to intercept and reduce future cVOC loading (via partitioning) and reduce oxygen inputs (via biostimulation). In the second and third parts, emulsified oil forms active bioremediation reactor zones within the plume footprint to degrade existing groundwater contamination (via reductive dechlorination and/or cometabolism) and stimulates long-term attenuation capacity in the distal plume (via

  7. Gamma-Glutamyl Cysteine Attenuates Tissue Damage and Enhances Tissue Regeneration in a rat Model of Lead-Induced Nephrotoxicity.

    PubMed

    Salama, Samir A; Arab, Hany H; Maghrabi, Ibrahim A; Hassan, Memy H; AlSaeed, Mohammed S

    2016-09-01

    Lead is a biohazardous metal that is commonly involved in human illness including renal injury. Although it is a non-redox reactive metal, lead-induced renal injury is largely based on oxidative stress. The current work aimed at exploring the possible protective effect of γ-glutamyl cysteine (γGC) against lead-induced renal injury. Rats were allocated to normal and γGC control groups, lead-treated group, and lead and γGC-treated group. γGC alleviated lead-induced renal injury as evidenced by attenuation of histopathological aberration, amelioration of oxidative injury as demonstrated by significant reduction in lipid and protein oxidation, elevation of total antioxidant capacity, and glutathione level. The activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) was significantly elevated. γGC significantly decreased levels of the proinflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β and the activity of the apoptotic marker caspase-3. In addition, γGC reduced kidney lead content, enhanced weight gain, and improved renal function as demonstrated by reduced serum levels of urea and creatinine. Importantly, γGC upregulated proliferating cell nuclear antigen (PCNA) expression, denoting enhanced renal regenerative capacity. Together, our findings highlight evidence for alleviating effects of γGC against lead-induced renal injury that is potentially mediated through diminution of oxidative tissue injury, reduction of inflammatory response, attenuation of apoptosis, and enhancement of renal regenerative capacity.

  8. Enhanced astroglial GABA uptake attenuates tonic GABAA inhibition of the presympathetic hypothalamic paraventricular nucleus neurons in heart failure.

    PubMed

    Pandit, Sudip; Jo, Ji Yoon; Lee, Sang Ung; Lee, Young Jae; Lee, So Yeong; Ryu, Pan Dong; Lee, Jung Un; Kim, Hyun-Woo; Jeon, Byeong Hwa; Park, Jin Bong

    2015-08-01

    γ-Aminobutyric acid (GABA) generates persistent tonic inhibitory currents (Itonic) and conventional inhibitory postsynaptic currents in the hypothalamic paraventricular nucleus (PVN) via activation of GABAA receptors (GABAARs). We investigated the pathophysiological significance of astroglial GABA uptake in the regulation of Itonic in the PVN neurons projecting to the rostral ventrolateral medulla (PVN-RVLM). The Itonic of PVN-RVLM neurons were significantly reduced in heart failure (HF) compared with sham-operated (SHAM) rats. Reduced Itonic sensitivity to THIP argued for the decreased function of GABAAR δ subunits in HF, whereas similar Itonic sensitivity to benzodiazepines argued against the difference of γ2 subunit-containing GABAARs in SHAM and HF rats. HF Itonic attenuation was reversed by a nonselective GABA transporter (GAT) blocker (nipecotic acid, NPA) and a GAT-3 selective blocker, but not by a GAT-1 blocker, suggesting that astroglial GABA clearance increased in HF. Similar and minimal Itonic responses to bestrophin-1 blockade in SHAM and HF neurons further argued against a role for astroglial GABA release in HF Itonic attenuation. Finally, the NPA-induced inhibition of spontaneous firing was greater in HF than in SHAM PVN-RVLM neurons, whereas diazepam induced less inhibition of spontaneous firing in HF than in SHAM neurons. Overall, our results showed that combined with reduced GABAARs function, the enhanced astroglial GABA uptake-induced attenuation of Itonic in HF PVN-RVLM neurons explains the deficit in tonic GABAergic inhibition and increased sympathetic outflow from the PVN during heart failure.

  9. Enhanced oil production in a mature field assisted by spectral attenuation analysis

    NASA Astrophysics Data System (ADS)

    Ramírez-Cruz, Luis C.; del Valle-García, Raúl; Urrutia Fucugauchi, Jaime

    2005-03-01

    Seismic attenuation analysis is used to distinguish changes in the spectral and amplitude characteristics of the seismic signal with the purpose of identifying the presence of fluids and fractures within the rock system. The analysis of such changes can be used as a tool for characterizing rock properties and for understanding the behaviour of wave propagation in a complex environment comprised by pores and cracks containing fluids. The study is carried out using high-resolution reflection data obtained from a mature fractured carbonate reservoir near the northeast coast of Mexico. Production from this reservoir is declining considerably. For this reason, a horizontal drilling programme is being considered. The results obtained from in situ measurements indicate that spectral changes and attenuation anomalies are related to the presence of hydrocarbons in the fractured reservoir rocks; however, such anomalies are also related to wave scattering in highly fractured areas. The seismic attenuation patterns associated with the productive zones have helped to identify new potential areas and horizontal drilling targets.

  10. Cavitation-enhanced back projection for acoustic detection of attenuating structures

    NASA Astrophysics Data System (ADS)

    Ramaekers, Pascal; de Greef, Martijn; Moonen, Chrit T. W.; Ries, Mario

    2017-03-01

    Current methodology for the detection of attenuating structures in abdominal HIFU interventions requires lengthy, elaborate image analysis, which is undesired in a clinical setting. In this work, a method for the acoustic detection of attenuating structures in the beam path of the therapeutic HIFU array is described. The proposed method is used to determine binary apodizations that can be applied to the HIFU transducer for intercostal shot positions. Such a binary apodization was determined in vivo on an anesthetized pig under controlled breathing. Validation of the proposed method was done by comparing the binary apodization based on the proposed method to a binary apodization obtained using methodology based on MR image analysis and a collision detection algorithm. The proposed acoustical method provided a binary apodization that was over 90% similar to the apodization obtained using the image analysis-based method. Additionally, the proposed method can provide a measure of the amount of attenuation that each respective transducer element encounters in its beam path towards the focus.

  11. Dioscorea bulbifera polysaccharide and cyclophosphamide combination enhances anti-cervical cancer effect and attenuates immunosuppression and oxidative stress in mice.

    PubMed

    Cui, Hongxia; Li, Ting; Wang, Liping; Su, Yan; Xian, Cory J

    2016-01-12

    Cyclophosphamide (CTX) is commonly used in cancer chemotherapy, which causes immunosuppression and tissue oxidative stress at high doses. As potential protective agents, some polysaccharides were shown to have anti-tumor, anti-inflammatory and/or anti-oxidant properties. This study explored potential effects of oral treatment of Dioscorea bulbifera polysaccharides (DBLP at 100 or 150 mg/kg) in U14 cervical tumor-bearing mice treated with CTX (25 mg/kg). While CTX suppressed tumor growth (65.4% inhibition) and DBLP alone also inhibited tumor (25.6% at 100 mg/kg or 37.6% at 150 mg/kg), CTX+DBLP combination produced tumor inhibition rates of 5.6 (for 100 mg/kg DBLP) or 9% (for 150 mg/kg) higher than CTX alone. While tumor itself and CTX treatment reduced thymus and/or spleen/body weight indices, DBLP alone or CTX + DBLP combination attenuated this reduction. DBLP lowered peripheral blood T-cell subpopulation CD(4+)/CD(8+) ratio, and DBLP+CTX combination attenuated CTX effect in lifting CD(4+)/CD(8+) ratio. Tumor itself and CTX treatment heightened oxidative stress (with decreased superoxide dismutase but increased lactate dehydrogenase and malondialdehyde levels in serum and tissues), which was attenuated by DBLP treatment, and DBLP+CTX combination suppressed CTX-induced oxidative stress. Combination use of DBLP with CTX can potentially enhance CTX anti-tumor effect and can attenuate CTX-induced immunosuppression and oxidative stress in U14 cervical tumor-bearing mice.

  12. Attenuation of experimental colitis in glutathione peroxidase 1 and catalase double knockout mice through enhancing regulatory T cell function.

    PubMed

    Kim, Hyung-Ran; Lee, Anbok; Choi, Eun-Jeong; Kie, Jeong-Hae; Lim, Woosung; Lee, Hyeon Kook; Moon, Byung-In; Seoh, Ju-Young

    2014-01-01

    Reactive oxygen species (ROS) have been implicated in the progression of inflammatory diseases including inflammatory bowel diseases (IBD). Meanwhile, several studies suggested the protective role of ROS in immune-mediated inflammatory diseases, and it was recently reported that dextran sodium sulfate (DSS)-induced colitis was attenuated in mice with an elevated level of ROS due to deficiency of peroxiredoxin II. Regulatory T cells (Tregs) are critical in the prevention of IBD and Treg function was reported to be closely associated with ROS level, but it has been investigated only in lowered levels of ROS so far. In the present study, in order to clarify the relationship between ROS level and Treg function, and their role in the pathogenesis of IBD, we investigated mice with an elevated level of ROS due to deficiency of both glutathione peroxidase (GPx)-1 and catalase (Cat) for the susceptibility of DSS-induced colitis in association with Treg function. The results showed that DSS-induced colitis was attenuated and Tregs were hyperfunctional in GPx1-/- × Cat-/- mice. In vivo administration of N-acetylcysteine (NAC) aggravated DSS-induced colitis and decreased Treg function to the level comparable to WT mice. Attenuated Th17 cell differentiation from naïve CD4+ cells as well as impaired production of IL-6 and IL-17A by splenocytes upon stimulation suggested anti-inflammatory tendency of GPx1-/- × Cat-/- mice. Suppression of Stat3 activation in association with enhancement of indoleamine 2,3-dioxygenase and FoxP3 expression might be involved in the immunosuppressive mechanism of GPx1-/- × Cat-/- mice. Taken together, it is implied that ROS level is critical in the regulation of Treg function, and IBD may be attenuated in appropriately elevated levels of ROS.

  13. Dioscorea bulbifera polysaccharide and cyclophosphamide combination enhances anti-cervical cancer effect and attenuates immunosuppression and oxidative stress in mice

    PubMed Central

    Cui, Hongxia; Li, Ting; Wang, Liping; Su, Yan; Xian, Cory J.

    2016-01-01

    Cyclophosphamide (CTX) is commonly used in cancer chemotherapy, which causes immunosuppression and tissue oxidative stress at high doses. As potential protective agents, some polysaccharides were shown to have anti-tumor, anti-inflammatory and/or anti-oxidant properties. This study explored potential effects of oral treatment of Dioscorea bulbifera polysaccharides (DBLP at 100 or 150 mg/kg) in U14 cervical tumor-bearing mice treated with CTX (25 mg/kg). While CTX suppressed tumor growth (65.4% inhibition) and DBLP alone also inhibited tumor (25.6% at 100 mg/kg or 37.6% at 150 mg/kg), CTX+DBLP combination produced tumor inhibition rates of 5.6 (for 100 mg/kg DBLP) or 9% (for 150 mg/kg) higher than CTX alone. While tumor itself and CTX treatment reduced thymus and/or spleen/body weight indices, DBLP alone or CTX + DBLP combination attenuated this reduction. DBLP lowered peripheral blood T-cell subpopulation CD4+/CD8+ ratio, and DBLP+CTX combination attenuated CTX effect in lifting CD4+/CD8+ ratio. Tumor itself and CTX treatment heightened oxidative stress (with decreased superoxide dismutase but increased lactate dehydrogenase and malondialdehyde levels in serum and tissues), which was attenuated by DBLP treatment, and DBLP+CTX combination suppressed CTX-induced oxidative stress. Combination use of DBLP with CTX can potentially enhance CTX anti-tumor effect and can attenuate CTX-induced immunosuppression and oxidative stress in U14 cervical tumor-bearing mice. PMID:26753518

  14. Colourful categories

    NASA Astrophysics Data System (ADS)

    Gromov, M. L.

    2015-08-01

    This paper presents Ramsey theory in category-theoretic terms as a message from a non-expert author to a non-expert reader. Everything is explained starting from the level zero, and an attempt is made to be as self-explanatory in the terminology and notation as possible. For the sake of references, the paper also reproduces traditional terminology, with concepts and theorems often named after (presumed) discoverers who are largely unknown to outsiders to the field. The sources are referred to in a manner so as to make them easy to find on the web; only exceptionally are non-freely accessible items referred to. Certain questions are formulated as 'conjectures', not out of a deep belief in their validity but because they sound better stated explicitly. There are no new results in this article, no deepening of particular aspects of Ramsey theory, no attempts to be comprehensive. But, in the spirit of the ideas of Anatoly Vershik, an attempt is made to move transversally across common directions of research, to see interrelations between them and to formulate questions. In fact, the article reproduces a chapter from the author's as yet unfinished manuscript "A number of questions". Bibliography: 65 titles.

  15. Natural and Enhanced Attenuation of Chlorinated Solvents Using RT3D

    SciTech Connect

    Johnson, Christian D.; Truex, Michael J.; Clement, T P.

    2006-07-25

    RT3D (Reactive Transport in 3-Dimensions) is a reactive transport code that can be applied to model solute fate and transport for many different purposes. This document specifically addresses application of RT3D for modeling related to evaluation and implementation of Monitored Natural Attenuation (MNA). Selection of MNA as a remedy requires an evaluation process to demonstrate that MNA will meet the remediation goals. The U.S. EPA, through the Office of Solid Waste and Emergency Response (OSWER) Directive 9200.4?17P, provides the regulatory context for the evaluation and implementation of MNA. In a complementary fashion, the context for using fate and transport modeling as part of MNA evaluation is described in the EPA?s technical protocol for chlorinated solvent MNA, the Scenarios Evaluation Tool for Chlorinated Solvent MNA, and in this document. The intent of this document is to describe (1) the context for applying RT3D for chlorinated solvent MNA and (2) the attenuation processes represented in RT3D, (3) dechlorination reactions that may occur, and (4) the general approach for using RT3D reaction modules (including a summary of the RT3D reaction modules that are available) to model fate and transport of chlorinated solvents as part of MNA or for combinations of MNA and selected types of active remediation.

  16. Diminazene aceturate enhances ACE2 activity and attenuates ischemia-induced cardiac pathophysiology

    PubMed Central

    Qi, YanFei; Zhang, Juan; Cole-Jeffrey, Colleen T; Shenoy, Vinayak; Espejo, Andrew; Hanna, Mina; Song, Chunjuan; Pepine, Carl J; Katovich, Michael J; Raizada, Mohan K

    2013-01-01

    Angiotensin-converting enzyme 2 (ACE2) plays a critical role against myocardial infarction (MI). We hypothesized that activation of intrinsic ACE2 would be protective against ischemia-induced cardiac pathophysiology. Diminazine aceturate (DIZE), a small molecule ACE2 activator has been used to evaluate this hypothesis. DIZE (15 mg/kg/day, s.c.) was injected two days prior to MI surgery and continued throughout the study-period. MI rats showed a 62% decrease in fractional shortening (FS,%) [control (Con): 51.1 ± 3.2; DIZE alone (D) : 52.1 ± 3.2; MI (M): 19.1± 3.0], a 55% decrease in contractility (dP/dtmax mmHg/s) (Con: 9480 ± 425.3; D: 9585 ± 597.4; M: 4251 ± 657.7), and a 27% increase in ventricular hypertrophy [VH, mg/mm (Con: 26.5 ± 1.5; D: 26.9 ± 1.4; M: 33.4± 1.1)]. DIZE attenuated the MI-induced decrease in FS by 89%, improved dP/dtmax by 92%, and reversed VH by 18%. MI also significantly increased ACE and angiotensin type 1 receptor levels while decreased ACE2 activity by 40% (Con: 246.2 ± 25.1; D: 254.2 ± 20.6; M: 148.9 ± 29.2, RFU/min), which was reversed by DIZE treatment. Thus, DIZE treatment decreased the infarct area, attenuated LV remodeling post-MI and restored normal balance of the cardiac renin angiotensin system. Additionally, DIZE treatment increased circulating endothelial progenitor cells, increased engraftment of cardiac progenitor cells and decreased inflammatory cells in peri-infarct cardiac regions. All of the beneficial effects associated with DIZE treatment were abolished by C-16, an ACE2 inhibitor. Collectively, DIZE and DIZE-like small molecules may represent promising new therapeutic agents for MI. PMID:23959549

  17. β-Integrin de-phosphorylation by the Density-Enhanced Phosphatase DEP-1 attenuates EGFR signaling in C. elegans

    PubMed Central

    Umbricht, Christoph Alois; Fröhli, Erika

    2017-01-01

    Density-Enhanced Phosphatase-1 (DEP-1) de-phosphorylates various growth factor receptors and adhesion proteins to regulate cell proliferation, adhesion and migration. Moreover, dep-1/scc1 mutations have been detected in various types of human cancers, indicating a broad tumor suppressor activity. During C. elegans development, DEP-1 mediates binary cell fate decisions by negatively regulating EGFR signaling. Using a substrate-trapping DEP-1 mutant in a proteomics approach, we have identified the C. elegans β-integrin subunit PAT-3 as a specific DEP-1 substrate. DEP-1 selectively de-phosphorylates tyrosine 792 in the membrane-proximal NPXY motif to promote integrin activation via talin recruitment. The non-phosphorylatable β-integrin mutant pat-3(Y792F) partially suppresses the hyperactive EGFR signaling phenotype caused by loss of dep-1 function. Thus, DEP-1 attenuates EGFR signaling in part by de-phosphorylating Y792 in the β-integrin cytoplasmic tail, besides the direct de-phosphorylation of the EGFR. Furthermore, in vivo FRAP analysis indicates that the αβ-integrin/talin complex attenuates EGFR signaling by restricting receptor mobility on the basolateral plasma membrane. We propose that DEP-1 regulates EGFR signaling via two parallel mechanisms, by direct receptor de-phosphorylation and by restricting receptor mobility through αβ-integrin activation. PMID:28135265

  18. Absence of Protoheme IX Farnesyltransferase CtaB Causes Virulence Attenuation but Enhances Pigment Production and Persister Survival in MRSA

    PubMed Central

    Xu, Tao; Han, Jian; Zhang, Jia; Chen, Jiazhen; Wu, Nan; Zhang, Wenhong; Zhang, Ying

    2016-01-01

    The membrane protein CtaB in S. aureus is a protoheme IX farnesyltransferase involved in the synthesis of the heme containing terminal oxidases of bacterial respiratory chain. In this study, to assess the role of CtaB in S. aureus virulence, pigment production, and persister formation, we constructed a ctaB mutant in the methicillin-resistant Staphylococcus aureus (MRSA) strain USA500. We found that deletion of ctaB attenuated growth and virulence in mice but enhanced pigment production and formation of quinolone tolerant persister cells in stationary phase. RNA-seq analysis showed that deletion of ctaB caused decreased transcription of several virulence genes including RNAIII which is consistent with its virulence attenuation. In addition, transcription of 20 ribosomal genes and 24 genes involved in amino acid biosynthesis was significantly down-regulated in the ctaB knockout mutant compared with the parent strain. These findings suggest the importance of heme biosynthesis in virulence and persister formation of S. aureus. PMID:27822202

  19. Infection-enhancing lipopeptides do not improve intranasal immunization of cotton rats with a delta-G candidate live-attenuated human respiratory syncytial virus vaccine.

    PubMed

    Tien Nguyen, D; Boes, Jolande; van Amerongen, Geert; van Remmerden, Yvonne; Yüksel, Selma; Guichelaar, Teun; Osterhaus, Albert D M E; de Swart, Rik L

    2013-12-01

    Development of live-attenuated human respiratory syncytial virus (HRSV) vaccines has proven to be difficult. Several vaccine candidates were found to be over-attenuated and displayed limited immunogenicity. Recently, we identified three synthetic cationic lipopeptides that enhanced paramyxovirus infections in vitro. The infection enhancement proved to be mediated by enhanced virus binding to target cells. We hypothesized that these lipopeptides can be used as adjuvants to promote immune responses induced by live-attenuated paramyxovirus vaccines. This hypothesis was tested in a vaccination and challenge model in cotton rats, using a previously described recombinant live-attenuated candidate HRSV vaccine lacking the gene encoding the G glycoprotein (rHRSVΔG). Surprisingly, intranasal vaccination of cotton rats with rHRSVΔG formulated in infection-enhancing lipopeptides resulted in reduced virus loads in nasopharyngeal lavages, reduced seroconversion levels and reduced protection from wild-type HRSV challenge. In conclusion, we were unable to demonstrate the feasibility of lipopeptides as adjuvants for a candidate live-attenuated HRSV vaccine in the cotton rat model.

  20. Taurine attenuates hippocampal and corpus callosum damage, and enhances neurological recovery after closed head injury in rats.

    PubMed

    Gu, Y; Zhao, Y; Qian, K; Sun, M

    2015-04-16

    The protective effects of taurine against closed head injury (CHI) have been reported. This study was designed to investigate whether taurine reduced white matter damage and hippocampal neuronal death through suppressing calpain activation after CHI in rats. Taurine (50 mg/kg) was administered intravenously 30 min and 4 h again after CHI. It was found that taurine lessened the corpus callosum damage, attenuated the neuronal cell death in hippocampal CA1 and CA3 subfields and improved the neurological functions 7 days after CHI. Moreover, it suppressed the over-activation of calpain, enhanced the levels of calpastatin, and reduced the degradation of neurofilament heavy protein, myelin basic protein and αII-spectrin in traumatic tissue 24 h after CHI. These data confirm the protective effects of taurine against gray and white matter damage due to CHI, and suggest that down-regulating calpain activation could be one of the protective mechanisms of taurine against CHI.

  1. Does phosphate enhance the natural attenuation of crude oil in groundwater under defined redox conditions?

    NASA Astrophysics Data System (ADS)

    Ponsin, Violaine; Mouloubou, Olsen Raïnness; Prudent, Pascale; Höhener, Patrick

    2014-11-01

    After a crude oil spill caused by a broken pipeline in 2009 to a gravel aquifer in southern France, degradation processes under various redox conditions progressively established, but at rates that predict a long life-time of the source under natural attenuation after partial source removal. In this study, we aimed at identifying the rate-limiting factors for each redox condition, with special emphasis on phosphate as limiting nutrient. The study was conducted in laboratory microcosms assembled with material collected on site: sediments, water from monitoring wells, oil and microbial sludge. Redox conditions were promoted by adding electron acceptors (either oxygen, nitrate, limonite (FeO(OH)), cryptomelane (K(Mn4 +,Mn2 +)8O16), or sulfate). For each condition, the role of phosphate was studied by repeated additions for up to 290 days. The results showed a very strong stimulation of aerobic and denitrifying rates of oil degradation by phosphate, provided that oxygen and nitrate were repeatedly supplied. Phosphate caused also a marked stimulation of methanogenic degradation, and a relatively small stimulation of metal reduction. These anaerobic processes started only after marked lag phases, and phosphate shortened the lag phase for methanogenic degradation. Degradation of aromatic and aliphatic hydrocarbons with less than 8 carbons, including benzene, was confirmed even under unstimulated conditions. It is concluded that degradation rates at the site are limited by both, availability of electron acceptors and availability of phosphate needed for promoting microbial growth.

  2. SA 4503 attenuates cocaine-induced hyperactivity and enhances methamphetamine substitution for a cocaine discriminative stimulus.

    PubMed

    Rodvelt, Kelli R; Lever, Susan Z; Lever, John R; Blount, Lucas R; Fan, Kuo-Hsien; Miller, Dennis K

    2011-02-01

    Cocaine exhibits preferential (~15-fold) affinity for σ₁ over σ₂ sigma receptors, and previous research has shown an interaction of σ₁ receptor-selective ligands and cocaine's behavioral effects. The present study investigated the effect of the putative sigma receptor agonist SA 4503 (1-(3,4-dimethoxyphenethyl)-4-(3-phenylpropyl)piperazine dihydrochloride) on cocaine's locomotor stimulatory and discriminative stimulus properties. At doses without intrinsic activity, SA 4503 dose-dependently attenuated cocaine-induced hyperactivity in mice. This inhibition was overcome by increasing the cocaine dose. In rats trained to use cocaine as a discriminative stimulus in a drug discrimination task, doses of SA 4503 that did not substitute for the cocaine stimulus did not alter the cocaine substitution curve. However, SA 4503 potentiated the effect of methamphetamine to substitute for the cocaine stimulus. These data support a role for sigma receptors in the locomotor-activating properties of cocaine and, importantly, indicate a role for these receptors in the discriminative stimulus effects of methamphetamine. The data also suggest sigma receptors mediate the activity of different dopamine pathways responsible for the behavioral effects of psychostimulants.

  3. Peripheral neuron plasticity is enhanced by brief electrical stimulation and overrides attenuated regrowth in experimental diabetes.

    PubMed

    Singh, B; Krishnan, A; Micu, I; Koshy, K; Singh, V; Martinez, J A; Koshy, D; Xu, F; Chandrasekhar, A; Dalton, C; Syed, N; Stys, P K; Zochodne, D W

    2015-11-01

    Peripheral nerve regrowth is less robust than commonly assumed, particularly when it accompanies common clinical scenarios such as diabetes mellitus. Brief extracellular electrical stimulation (ES) facilitates the regeneration of peripheral nerves in part through early activation of the conditioning injury response and BDNF. Here, we explored intrinsic neuronal responses to ES to identify whether ES might impact experimental diabetes, where regeneration is attenuated. ES altered several regeneration related molecules including rises in tubulin, Shh (Sonic hedgehog) and GAP43 mRNAs. ES was associated with rises in neuronal intracellular calcium but its strict linkage to regrowth was not confirmed. In contrast, we identified PI3K-PTEN involvement, an association previously linked to diabetic regenerative impairment. Following ES there were declines in PTEN protein and mRNA both in vitro and in vivo and a PI3K inhibitor blocked its action. In vitro, isolated diabetic neurons were capable of mounting robust responsiveness to ES. In vivo, ES improved electrophysiological and behavioral indices of nerve regrowth in a chronic diabetic model of mice with pre-existing neuropathy. Regrowth of myelinated axons and reinnervation of the epidermis were greater following ES than sham stimulation. Taken together, these findings identify a role for ES in supporting regeneration during the challenges of diabetes mellitus.

  4. Dichloroacetate blocks aerobic glycolytic adaptation to attenuated measles virus and promotes viral replication leading to enhanced oncolysis in glioblastoma

    PubMed Central

    Su, Lei; Chen, Aiping; Xia, Mao; Xu, Chun; Yu, Decai; Jiang, Aiqin; Wei, Jiwu

    2015-01-01

    Targeting reprogrammed energy metabolism such as aerobic glycolysis is a potential strategy for cancer treatment. However, tumors exhibiting low-rate glycolysis or metabolic heterogeneity might be resistant to such treatment. We hypothesized that a therapeutic modality that drove cancer cells to high-rate glycolysis might sensitize cancer cells to interference directed against metabolic flux. In this study, we found that attenuated oncolytic measles virus Edmonston strain (MV-Edm) caused glioblastoma cells to shift to high-rate aerobic glycolysis; this adaptation was blocked by dichloroacetate (DCA), an inhibitor of glycolysis, leading to profound cell death of cancer cells but not of normal cells. DCA enhanced viral replication by mitigating mitochondrial antiviral signaling protein (MAVS)-mediated innate immune responses. In a subcutaneous glioblastoma (GBM) xenograft mouse model, low-dose MV-Edm and DCA significantly inhibited tumor growth in vivo. We found that DCA impaired glycolysis (blocking bioenergetic generation) and enhanced viral replication (increasing bioenergetic consumption), which, in combination, accelerated bioenergetic exhaustion leading to necrotic cell death. Taken together, oncolytic MV-Edm sensitized cancer cells to DCA, and in parallel, DCA promoted viral replication, thus, improving oncolysis. This novel therapeutic approach should be readily incorporated into clinical trials. PMID:25575816

  5. Attenuation of the posttranslational oscillator via transcription-translation feedback enhances circadian-phase shifts in Synechococcus.

    PubMed

    Hosokawa, Norimune; Kushige, Hiroko; Iwasaki, Hideo

    2013-08-27

    Circadian rhythms are endogenous biological timing processes that are ubiquitous in organisms ranging from cyanobacteria to humans. In the photoautotrophic unicellular cyanobacterium Synechococcus elongatus PCC 7942, under continuous light (LL) conditions, the transcription-translation feedback loop (TTFL) of KaiC generates a rhythmic change in the accumulation of KaiC relative to KaiA clock proteins (KaiC/KaiA ratio), which peak and trough at subjective dawn and dusk, respectively. However, the role of TTFL in the cyanobacterial circadian system remains unclear because it is not an essential requirement for the basic oscillation driven by the Kai-based posttranslational oscillator (PTO) and the transcriptional output mechanisms. Here, we show that TTFL is important for the circadian photic resetting property in Synechococcus. The robustness of PTO, which is exemplified by the amplitude of the KaiC phosphorylation cycle, changed depending on the KaiC/KaiA ratio, which was cyclic under LL. After cells were transferred from LL to the dark, the clock protein levels remained constant in the dark. When cells were transferred from LL to continuous dark at subjective dawn, the KaiC phosphorylation cycle was attenuated with a lower KaiC/KaiA ratio, a higher KaiC phosphorylation level, and a lower amplitude than that in cells transferred at subjective dusk. We also found that the greater the degree to which PTO was attenuated in continuous dark, the greater the phase shifts upon the subsequent light exposure. Based on these results, we propose that TTFL enhances resetting of the Kai-based PTO in Synechococcus.

  6. Natural and Enhanced Attenuation of Soil and Groundwater at the Monument Valley, Arizona, DOE Legacy Waste Site—10281

    SciTech Connect

    Waugh, W.J.; Miller, D.E.; Morris, S.A.; Sheader, L.R.; Glenn, E.P.; Moore, D.; Carroll, K.C.; Benally, L.; Roanhorse, M.; Bush, R.P.; none,

    2010-03-07

    The U.S. Department of Energy (DOE), the Navajo Nation, and the University of Arizona are exploring natural and enhanced attenuation remedies for groundwater contamination at a former uranium-ore processing site near Monument Valley, Arizona. DOE removed radioactive tailings from the Monument Valley site in 1994. Nitrate and ammonium, waste products of the milling process, remain in an alluvial groundwater plume spreading from the soil source where tailings were removed. Planting and irrigating two native shrubs, fourwing saltbush and black greasewood, markedly reduced both nitrate and ammonium in the source area over an 8-year period. Total nitrogen dropped from 350 mg/kg in 2000 to less than 200 mg/kg in 2008. Most of the reduction is attributable to irrigation-enhanced microbial denitrification rather than plant uptake. However, soil moisture and percolation flux monitoring show that the plantings control the soil water balance in the source area, preventing additional leaching of nitrogen compounds. Enhanced denitrification and phytoremediation also look promising for plume remediation. Microcosm experiments, nitrogen isotopic fractionation analysis, and solute transport modeling results suggest that (1) up to 70 percent of nitrate in the plume has been lost through natural denitrification since the mill was closed in 1968, and (2) injection of ethanol may accelerate microbial denitrification in plume hot spots. A field-scale ethanol injection pilot study is underway. Landscape-scale remote sensing methods developed for the project suggest that transpiration from restored native phreatophyte populations rooted in the aquifer could limit further expansion of the plume. An evaluation of landfarm phytoremediation, the irrigation of native shrub plantings with high nitrate water pumped from the alluvial aquifer, is also underway.

  7. Cell-Associated Flagella Enhance the Protection Conferred by Mucosally-Administered Attenuated Salmonella Paratyphi A Vaccines

    PubMed Central

    Gat, Orit; Galen, James E.; Tennant, Sharon; Simon, Raphael; Blackwelder, William C.; Silverman, David J.; Pasetti, Marcela F.; Levine, Myron M.

    2011-01-01

    Background Antibiotic-resistant Salmonella enterica serovar Paratyphi A, the agent of paratyphoid A fever, poses an emerging public health dilemma in endemic areas of Asia and among travelers, as there is no licensed vaccine. Integral to our efforts to develop a S. Paratyphi A vaccine, we addressed the role of flagella as a potential protective antigen by comparing cell-associated flagella with exported flagellin subunits expressed by attenuated strains. Methodology S. Paratyphi A strain ATCC 9150 was first deleted for the chromosomal guaBA locus, creating CVD 1901. Further chromosomal deletions in fliD (CVD 1901D) or flgK (CVD 1901K) were then engineered, resulting in the export of unpolymerized FliC, without impairing its overall expression. The virulence of the resulting isogenic strains was examined using a novel mouse LD50 model to accommodate the human-host restricted S. Paratyphi A. The immunogenicity of the attenuated strains was then tested using a mouse intranasal model, followed by intraperitoneal challenge with wildtype ATCC 9150. Results Mucosal (intranasal) immunization of mice with strain CVD 1901 expressing cell-associated flagella conferred superior protection (vaccine efficacy [VE], 90%) against a lethal intraperitoneal challenge, compared with the flagellin monomer-exporting mutants CVD 1901K (30% VE) or CVD 1901D (47% VE). The superior protection induced by CVD 1901 with its cell-attached flagella was associated with an increased IgG2a∶IgG1 ratio of FliC-specific antibodies with enhanced opsonophagocytic capacity. Conclusions Our results clearly suggest that enhanced anti-FliC antibody-mediated clearance of S. Paratyphi A by phagocytic cells, induced by vaccines expressing cell-associated rather than exported FliC, might be contributing to the vaccine-induced protection from S. Paratyphi A challenge in vivo. We speculate that an excess of IgG1 anti-FliC antibodies induced by the exported FliC may compete with the IgG2a subtype and block

  8. Octreotide Attenuates Acute Kidney Injury after Hepatic Ischemia and Reperfusion by Enhancing Autophagy

    PubMed Central

    Sun, Huiping; Zou, Shuangfa; Candiotti, Keith A.; Peng, Yanhua; Zhang, Qinya; Xiao, Weiqiang; Wen, Yiyun; wu, Jiao; Yang, Jinfeng

    2017-01-01

    Octreotide exerts a protective effect in hepatic ischemia-reperfusion (HIR) injury. However, whether octreotide preconditioning could also reduce acute kidney injury (AKI) after HIR is unknown. This study was designed to investigate the role of octreotide in AKI after HIR. Male Sprague-Dawley rats were pretreated with octreotide or octreotide combined with 3-methyladenine (autophagy inhibitor, 3MA). Plasma creatinine, inflammation markers (e.g., TNF-α and IL-6 etc.), apoptosis, autophagy and phosphorylation of protein kinase B/mammalian target of rapamycin/p70 ribosomal S6 kinase (Akt/mTOR/p70S6K) in the kidney were measured after 60 minutes of liver ischemia and 24 hours of reperfusion for each rat. Octreotide pretreatment significantly preserved renal function and reduced the severity of renal injury. Moreover, octreotide alleviated inflammation and apoptosis in the kidney after HIR. Additionally, octreotide induced autophagy and autophagy inhibition with 3MA markedly reversed the renoprotective, anti-inflammatory and anti-apoptotic effects of octreotide after HIR. Finally, octreotide abrogated the activation of phosphorylation of Akt, mTOR and p70S6K in the kidney after HIR. Our results indicate that octreotide reduced renal injury after HIR due to its induction of autophagy. The enhancement of autophagy may be potentially linked to the octreotide mediated Akt/mTOR/p70S6K pathway deactivation and reduction of kidney inflammation and apoptosis after HIR. PMID:28205545

  9. Berberine enhances antidiabetic effects and attenuates untoward effects of canagliflozin in streptozotocin-induced diabetic mice.

    PubMed

    Tian, Cai-Ming; Jiang, Xin; Ouyang, Xiao-Xi; Zhang, Ya-Ou; Xie, Wei-Dong

    2016-07-01

    The present study aimed at determining whether berberine can enhance the antidiabetic effects and alleviate the adverse effects of canagliflozin in diabetes mellitus. Streptozotocin-induced diabetic mice were introduced, and the combined effects of berberine and canagliflozin on glucose metabolism and kidney functions were investigated. Our results showed that berberine combined with canagliflozin (BC) increased reduction of fasting and postprandial blood glucose, diet, and water intake compared with berberine or canagliflozin alone. Interestingly, BC showed greater decrease in blood urea nitrogen and creatinine levels and lower total urine glucose excretion than canagliflozin alone. In addition, BC showed increased phosphorylated 5' AMP-activated protein kinase (pAMPK) expression and decreased tumor necrosis factor alpha (TNFα) levels in kidneys, compared with berberine or canagliflozin alone. These results indicated that BC was a stronger antidiabetic than berberine or canagliflozin alone with less negative side effects on the kidneys in the diabetic mice. The antidiabetic effect was likely to be mediated by synergically promoting the expression of pAMPK and reducing the expression of TNFα in kidneys. The present study represented the first report that canagliflozin combined with berberine was a promising treatment for diabetes mellitus. The exact underlying mechanisms of action should be investigated in future studies.

  10. Saikokeishito Extract Exerts a Therapeutic Effect on alpha-Naphthylisothiocyanate-Induced Liver Injury in Rats through Attenuation of Enhanced Neutrophil Infiltration and Oxidative Stress in the Liver Tissue.

    PubMed

    Ohta, Yoshiji; Kongo-Nishimura, Mutsumi; Hayashi, Takahiro; Kitagawa, Akira; Matsura, Tatsuya; Yamada, Kazuo

    2007-01-01

    We examined whether Saikokeishito extract (TJ-10), a traditional Japanese herbal medicine, exerts a therapeutic effect on alpha-naphthylisothiocyanate (ANIT)-induced liver injury in rats through attenuation of enhanced neutrophil infiltration and oxidative stress in the liver tissue. In rats treated once with ANIT (75 mg/kg, i.p.), liver injury with cholestasis occurred 24 h after treatment and progressed at 48 h. When ANIT-treated rats orally received TJ-10 (0.26, 1.3 or 2.6 g/kg) at 24 h after the treatment, progressive liver injury with cholestasis was significantly attenuated at 48 h after the treatment at the dose of 1.3 or 2.6 g/kg. At 24 h after ANIT treatment, increases in hepatic lipid peroxide and reduced glutathione contents and myeloperoxidase activity occurred with decreases in hepatic superoxide dismutase and glutathione reductase activities. At 48 h after ANIT treatment, these changes except for reduced glutathione were enhanced with decreases in catalase, Se-glutathione peroxidase, and glucose-6-phosphate dehydrogenase activities. TJ-10 (1.3 or 2.6 g/kg) post-administered to ANIT-treated rats attenuated these changes found at 48 h after the treatment significantly. These results indicate that TJ-10 exerts a therapeutic effect on ANIT-induced liver injury in rats possibly through attenuation of enhanced neutrophil infiltration and oxidative stress in the liver tissue.

  11. Generation and preclinical evaluation of a DENV-1/2 prM+E chimeric live attenuated vaccine candidate with enhanced prM cleavage.

    PubMed

    Keelapang, Poonsook; Nitatpattana, Narong; Suphatrakul, Amporn; Punyahathaikul, Surat; Sriburi, Rungtawan; Pulmanausahakul, Rojjanaporn; Pichyangkul, Sathit; Malasit, Prida; Yoksan, Sutee; Sittisombut, Nopporn

    2013-10-17

    In the absence of a vaccine or sustainable vector control measures, illnesses caused by dengue virus infection remain an important public health problem in many tropical countries. During the export of dengue virus particles, furin-mediated cleavage of the prM envelope protein is usually incomplete, thus generating a mixture of immature, partially mature and mature extracellular particles. Variations in the arrangement and conformation of the envelope proteins among these particles may be associated with their different roles in shaping the antibody response. In an attempt to improve upon live, attenuated dengue vaccine approaches, a mutant chimeric virus, with enhanced prM cleavage, was generated by introducing a cleavage-enhancing substitution into a chimeric DENV-1/2 virus genome, encoding the prM+E sequence of a recent DENV-1 isolate under an attenuated DENV-2 genetic background. A modest increase in virus specific infectivity observed in the mutant chimeric virus affected neither the attenuation phenotype, when assessed in the suckling mouse neurovirulence model, nor multiplication in mosquitoes. The two chimeric viruses induced similar levels of anti-DENV-1 neutralizing antibody response in mice and rhesus macaques, but more efficient control of viremia during viral challenge was observed in macaques immunized with the mutant chimeric virus. These results indicate that the DENV-1/2 chimeric virus, with enhanced prM cleavage, could be useful as an alternative live, attenuated vaccine candidate for further tests in humans.

  12. Microbial respiration and natural attenuation of benzene contaminated soils investigated by cavity enhanced Raman multi-gas spectroscopy.

    PubMed

    Jochum, Tobias; Michalzik, Beate; Bachmann, Anne; Popp, Jürgen; Frosch, Torsten

    2015-05-07

    Soil and groundwater contamination with benzene can cause serious environmental damage. However, many soil microorganisms are capable to adapt and are known to strongly control the fate of organic contamination. Innovative cavity enhanced Raman multi-gas spectroscopy (CERS) was applied to investigate the short-term response of the soil micro-flora to sudden surface contamination with benzene regarding the temporal variations of gas products and their exchange rates with the adjacent atmosphere. (13)C-labeled benzene was spiked on a silty-loamy soil column in order to track and separate the changes in heterotrophic soil respiration - involving (12)CO2 and O2- from the natural attenuation process of benzene degradation to ultimately form (13)CO2. The respiratory quotient (RQ) decreased from a value 0.98 to 0.46 directly after the spiking and increased again within 33 hours to a value of 0.72. This coincided with the maximum (13)CO2 concentration rate (0.63 μmol m(-2) s(-1)), indicating the highest benzene degradation at 33 hours after the spiking event. The diffusion of benzene in the headspace and the biodegradation into (13)CO2 were simultaneously monitored and 12 days after the benzene spiking no measurable degradation was detected anymore. The RQ finally returned to a value of 0.96 demonstrating the reestablished aerobic respiration.

  13. Enhancement of Gastric Ulcer Healing and Angiogenesis by Hepatocyte Growth Factor Gene Mediated by Attenuated Salmonella in Rats

    PubMed Central

    2017-01-01

    The present study developed an oral hepatocyte growth factor (HGF) gene therapy strategy for gastric ulcers treatment. An attenuated Salmonella typhimurium that stably expressed high HGF (named as TPH) was constructed, and the antiulcerogenic effect of TPH was evaluated in a rat model of gastric ulcers that created by acetic acid subserosal injection. From day 5 after injection, TPH (1 × 109 cfu), vehicle (TP, 1 × 109 cfu), or sodium bicarbonate (model control) was administered orally every alternate day for three times. Then ulcer size was measured at day 21 after ulcer induction. The ulcer area in TPH-treated group was 10.56 ± 3.30 mm2, which was smaller when compared with those in the TP-treated and model control groups (43.47 ± 4.18 and 56.25 ± 6.38 mm2, respectively). A higher level of reepithelialization was found in TPH-treated group and the crawling length of gastric epithelial cells was significantly longer than in the other two groups (P < 0.05). The microvessel density in the ulcer granulation tissues of the TPH-treated rats was 39.9 vessels/mm2, which was greater than in the TP-treated and model control rats, with a significant statistical difference. These results suggest that TPH treatment significantly accelerates the healing of gastric ulcers via stimulating proliferation of gastric epithelial cells and enhancing angiogenesis on gastric ulcer site. PMID:28049228

  14. AAV8-Mediated In Vivo Overexpression of miR-155 Enhances the Protective Capacity of Genetically Attenuated Malarial Parasites

    PubMed Central

    Hentzschel, Franziska; Hammerschmidt-Kamper, Christiane; Börner, Kathleen; Heiss, Kirsten; Knapp, Bettina; Sattler, Julia M; Kaderali, Lars; Castoldi, Mirco; Bindman, Julia G; Malato, Yann; Willenbring, Holger; Mueller, Ann-Kristin; Grimm, Dirk

    2014-01-01

    Malaria, caused by protozoan Plasmodium parasites, remains a prevalent infectious human disease due to the lack of an efficient and safe vaccine. This is directly related to the persisting gaps in our understanding of the parasite's interactions with the infected host, especially during the clinically silent yet essential liver stage of Plasmodium development. Previously, we and others showed that genetically attenuated parasites (GAP) that arrest in the liver induce sterile immunity, but only upon multiple administrations. Here, we comprehensively studied hepatic gene and miRNA expression in GAP-injected mice, and found both a broad activation of IFNγ-associated pathways and a significant increase of murine microRNA-155 (miR-155), that was especially pronounced in non-parenchymal cells including liver-resident macrophages (Kupffer cells). Remarkably, ectopic upregulation of this miRNA in the liver of mice using robust hepatotropic adeno-associated virus 8 (AAV8) vectors enhanced GAP's protective capacity substantially. In turn, this AAV8-mediated miR-155 expression permitted a reduction of GAP injections needed to achieve complete protection against infectious parasite challenge from previously three to only one. Our study highlights a crucial role of mammalian miRNAs in Plasmodium liver infection in vivo and concurrently implies their great potential as future immune-augmenting agents in improved vaccination regimes against malaria and other diseases. PMID:25189739

  15. Attenuating GABA(A) receptor signaling in dopamine neurons selectively enhances reward learning and alters risk preference in mice.

    PubMed

    Parker, Jones G; Wanat, Matthew J; Soden, Marta E; Ahmad, Kinza; Zweifel, Larry S; Bamford, Nigel S; Palmiter, Richard D

    2011-11-23

    Phasic dopamine (DA) transmission encodes the value of reward-predictive stimuli and influences both learning and decision-making. Altered DA signaling is associated with psychiatric conditions characterized by risky choices such as pathological gambling. These observations highlight the importance of understanding how DA neuron activity is modulated. While excitatory drive onto DA neurons is critical for generating phasic DA responses, emerging evidence suggests that inhibitory signaling also modulates these responses. To address the functional importance of inhibitory signaling in DA neurons, we generated mice lacking the β3 subunit of the GABA(A) receptor specifically in DA neurons (β3-KO mice) and examined their behavior in tasks that assessed appetitive learning, aversive learning, and risk preference. DA neurons in midbrain slices from β3-KO mice exhibited attenuated GABA-evoked IPSCs. Furthermore, electrical stimulation of excitatory afferents to DA neurons elicited more DA release in the nucleus accumbens of β3-KO mice as measured by fast-scan cyclic voltammetry. β3-KO mice were more active than controls when given morphine, which correlated with potential compensatory upregulation of GABAergic tone onto DA neurons. β3-KO mice learned faster in two food-reinforced learning paradigms, but extinguished their learned behavior normally. Enhanced learning was specific for appetitive tasks, as aversive learning was unaffected in β3-KO mice. Finally, we found that β3-KO mice had enhanced risk preference in a probabilistic selection task that required mice to choose between a small certain reward and a larger uncertain reward. Collectively, these findings identify a selective role for GABA(A) signaling in DA neurons in appetitive learning and decision-making.

  16. Humic Acids Enhanced U(VI) Attenuation in Acidic Waste Plumes: An In-situ Remediation Approach

    NASA Astrophysics Data System (ADS)

    Wan, J.; Dong, W.; Tokunaga, T. K.

    2010-12-01

    and HA by groundwater leaching are non-detectable over a long period of time (200 days and > 100 PV without further addition of HA). As a natural reactive agent for in-situ remediation, HAs are cost-effective (enormous reservoir in nature), nontoxic, resistant to biodegradation, soluble, and easily introducible to the subsurface. This method has high potential to efficiently and sustainably enhance natural attenuation of U within acidic waste plumes.

  17. Ideals and Category Typicality

    ERIC Educational Resources Information Center

    Kim, ShinWoo; Murphy, Gregory L.

    2011-01-01

    Barsalou (1985) argued that exemplars that serve category goals become more typical category members. Although this claim has received support, we investigated (a) whether categories have a single ideal, as negatively valenced categories (e.g., cigarette) often have conflicting goals, and (b) whether ideal items are in fact typical, as they often…

  18. Rank 4 Premodular Categories

    SciTech Connect

    Bruillard, Paul J.; Galindo, Cesar; Ng, Siu Hung; Plavnik, Julia; Rowell, Eric; Wang, Zhenghan

    2016-09-01

    We consider the classification problem for rank 4 premodular categories. We uncover a formula for the 2nd Frobenius-Schur indicator of a premodular category is determined and the classification of rank 4 premodular categories (up to Grothendieck equivalence) is completed. In the appendix we show rank finiteness for premodular categories.

  19. Enhanced Attenuation: Chlorinated Organics

    DTIC Science & Technology

    2008-04-01

    consequential, or punitive damages arising out of the use of any information, apparatus, method, or process discussed in ITRC products. ITRC product... processes has begun to diminish without remedial objectives being met. Other more effective remedial alternatives need to be implemented; however, there...remedial decision process . The EA approach is consistent with the current regulatory environment and can be accommodated within a broad range of regulatory

  20. Helenalin attenuates alcohol-induced hepatic fibrosis by enhancing ethanol metabolism, inhibiting oxidative stress and suppressing HSC activation.

    PubMed

    Lin, Xing; Zhang, Shijun; Huang, Renbin; Wei, Ling; Tan, Shimei; Liang, Shuang; Tian, Yuanchun; Wu, Xiaoyan; Lu, Zhongpeng; Huang, Quanfang

    2014-06-01

    A compound was isolated from Centipeda minima using bioassay-guided screening. The structure of this compound was elucidated based on its spectral data, and it was identified as helenalin. The hepatoprotective effect of helenalin was evaluated using a liver fibrosis model induced by intragastric administration with alcohol within 24 weeks in rats. The results revealed that helenalin significantly prevented alcohol-induced hepatic injury and fibrogenesis, as evidenced by the decrease in serum aminotransferase, the attenuation of histopathological changes, and the inhibition of the hepatic fibrosis indicators, such as hyaluronic acid, type III precollagen, laminin, hydroxyproline and collagen α type I. Mechanistically, studies showed that helenalin expedited ethanol metabolism by enhancing the alcohol and aldehyde dehydrogenase activities. Furthermore, helenalin alleviated lipid peroxidation, recruited the antioxidative defense system, inhibited CYP2E1 activity, and reduced the inflammatory mediators, including TGF-β1, TNF-α, IL-6 and IL-1β and myeloperoxidase, via down-regulation of NF-κB. Helenalin significantly decreased collagen deposition by reducing the profibrotic cytokines like transforming growth factor-β, platelet-derived growth factor-β and connective tissue growth factor, and promoted extracellular matrix degradation by modulating the levels of tissue inhibitor of matrix metalloproteinase-1 and matrix metalloproteinase-9. In addition, helenalin inhibited HSC activation as evidenced by the down-regulation of α-SMA and TGF-β levels. In conclusion, helenalin had a significant protective effect on chronic ethanol-induced hepatic fibrosis and may be a major bioactive ingredient of C. minima.

  1. Saikokeishito Extract Exerts a Therapeutic Effect on α-Naphthylisothiocyanate-Induced Liver Injury in Rats through Attenuation of Enhanced Neutrophil Infiltration and Oxidative Stress in the Liver Tissue

    PubMed Central

    Ohta, Yoshiji; Kongo-Nishimura, Mutsumi; Hayashi, Takahiro; Kitagawa, Akira; Matsura, Tatsuya; Yamada, Kazuo

    2007-01-01

    We examined whether Saikokeishito extract (TJ-10), a traditional Japanese herbal medicine, exerts a therapeutic effect on α-naphthylisothiocyanate (ANIT)-induced liver injury in rats through attenuation of enhanced neutrophil infiltration and oxidative stress in the liver tissue. In rats treated once with ANIT (75 mg/kg, i.p.), liver injury with cholestasis occurred 24 h after treatment and progressed at 48 h. When ANIT-treated rats orally received TJ-10 (0.26, 1.3 or 2.6 g/kg) at 24 h after the treatment, progressive liver injury with cholestasis was significantly attenuated at 48 h after the treatment at the dose of 1.3 or 2.6 g/kg. At 24 h after ANIT treatment, increases in hepatic lipid peroxide and reduced glutathione contents and myeloperoxidase activity occurred with decreases in hepatic superoxide dismutase and glutathione reductase activities. At 48 h after ANIT treatment, these changes except for reduced glutathione were enhanced with decreases in catalase, Se-glutathione peroxidase, and glucose-6-phosphate dehydrogenase activities. TJ-10 (1.3 or 2.6 g/kg) post-administered to ANIT-treated rats attenuated these changes found at 48 h after the treatment significantly. These results indicate that TJ-10 exerts a therapeutic effect on ANIT-induced liver injury in rats possibly through attenuation of enhanced neutrophil infiltration and oxidative stress in the liver tissue. PMID:18437211

  2. Categories of Arrhythmias

    MedlinePlus

    ... previous page En español Aneurysms and Dissections Angina Arrhythmia Bundle Branch Block Cardiomyopathy Carotid Artery Disease Chronic ... Cardiac Arrest Valve Disease Vulnerable Plaque Categories of Arrhythmias Arrhythmias are generally divided into two categories: ventricular ...

  3. Encoding tasks dissociate the effects of divided attention on category-cued recall and category-exemplar generation.

    PubMed

    Parker, Andrew; Dagnall, Neil; Munley, Gary

    2012-01-01

    The combined effects of encoding tasks and divided attention upon category-exemplar generation and category-cued recall were examined. Participants were presented with pairs of words each comprising a category name and potential example of that category. They were then asked to indicate either (i) their liking for both of the words or (ii) if the exemplar was a member of the category. It was found that divided attention reduced performance on the category-cued recall task under both encoding conditions. However, performance on the category-exemplar generation task remained invariant across the attention manipulation following the category judgment task. This provides further evidence that the processes underlying performance on conceptual explicit and implicit memory tasks can be dissociated, and that the intentional formation of category-exemplar associations attenuates the effects of divided attention on category-exemplar generation.

  4. Cerebrospinal Fluid Enhancement on Fluid Attenuated Inversion Recovery Images After Carotid Artery Stenting with Neuroprotective Balloon Occlusions: Hemodynamic Instability and Blood-Brain Barrier Disruption

    SciTech Connect

    Ogami, Ryo Nakahara, Toshinori; Hamasaki, Osamu; Araki, Hayato; Kurisu, Kaoru

    2011-10-15

    Purpose: A rare complication of carotid artery stenting (CAS), prolonged reversible neurological symptoms with delayed cerebrospinal fluid (CSF) space enhancement on fluid attenuated inversion recovery (FLAIR) images, is associated with blood-brain barrier (BBB) disruption. We prospectively identified patients who showed CSF space enhancement on FLAIR images. Methods: Nineteen patients-5 acute-phase and 14 scheduled-underwent 21 CAS procedures. Balloon catheters were navigated across stenoses, angioplasty was performed using a neuroprotective balloon, and stents were placed with after dilation under distal balloon protection. CSF space hyperintensity or obscuration on FLAIR after versus before CAS indicated CSF space enhancement. Correlations with clinical factors were examined. Results: CSF space was enhanced on FLAIR in 12 (57.1%) cases. Postprocedural CSF space enhancement was significantly related to age, stenosis rate, acute-stage procedure, and total occlusion time. All acute-stage CAS patients showed delayed enhancement. Only age was associated with delayed CSF space enhancement in scheduled CAS patients. Conclusions: Ischemic intolerance for severe carotid artery stenosis and temporary neuroprotective balloon occlusion, causing reperfusion injury, seem to be the main factors that underlie BBB disruption with delayed CSF space enhancement shortly after CAS, rather than sudden poststenting hemodynamic change. Our results suggest that factors related to hemodynamic instability or ischemic intolerance seem to be associated with post-CAS BBB vulnerability. Patients at risk for hemodynamic instability or with ischemic intolerance, which decrease BBB integrity, require careful management to prevent intracranial hemorrhagic and other post-CAS complications.

  5. BLOCKADE OF NERVE GROWTH FACTOR (NGF) RECEPTOR TRKA ATTENUATES DIESEL EXHAUST PARTICULATE MATTER (DEP) ENHANCEMENT OF ALLERGIC INFLAMMATION

    EPA Science Inventory


    Recent studies have shown that asthmatics have increased levels of the neurotrophin, NGF, in their lungs. In addition, antibody blockade of NGF in mice attenuates airway resistance associated with allergic airway responses. DEP has been linked to asthma exacerbation in many c...

  6. Single well field injection test of humate to enhance attenuation of uranium and other radionuclides in an acidic plume

    SciTech Connect

    Denham, M.

    2014-09-30

    This report documents the impact of the injected humate on targeted contaminants over a period of 4 months and suggests it is a viable attenuation-based remedy for uranium, potentially for I-129, but not for Sr-90. Future activities will focus on issues pertinent to scaling the technology to full deployment.

  7. Incidental Auditory Category Learning

    PubMed Central

    Gabay, Yafit; Dick, Frederic K.; Zevin, Jason D.; Holt, Lori L.

    2015-01-01

    Very little is known about how auditory categories are learned incidentally, without instructions to search for category-diagnostic dimensions, overt category decisions, or experimenter-provided feedback. This is an important gap because learning in the natural environment does not arise from explicit feedback and there is evidence that the learning systems engaged by traditional tasks are distinct from those recruited by incidental category learning. We examined incidental auditory category learning with a novel paradigm, the Systematic Multimodal Associations Reaction Time (SMART) task, in which participants rapidly detect and report the appearance of a visual target in one of four possible screen locations. Although the overt task is rapid visual detection, a brief sequence of sounds precedes each visual target. These sounds are drawn from one of four distinct sound categories that predict the location of the upcoming visual target. These many-to-one auditory-to-visuomotor correspondences support incidental auditory category learning. Participants incidentally learn categories of complex acoustic exemplars and generalize this learning to novel exemplars and tasks. Further, learning is facilitated when category exemplar variability is more tightly coupled to the visuomotor associations than when the same stimulus variability is experienced across trials. We relate these findings to phonetic category learning. PMID:26010588

  8. Asian women have attenuated sympathetic activation but enhanced renal–adrenal responses during pregnancy compared to Caucasian women

    PubMed Central

    Okada, Yoshiyuki; Best, Stuart A; Jarvis, Sara S; Shibata, Shigeki; Parker, Rosemary S; Casey, Brian M; Levine, Benjamin D; Fu, Qi

    2015-01-01

    women. This is the first longitudinal study to investigate neural and humoral responses during pregnancy in Asians and Caucasians. The key finding was that Asians had attenuated sympathetic activation but enhanced renal–adrenal responsiveness during pregnancy compared to Caucasians. These results may provide insights into the pathophysiological mechanisms for racial differences in the prevalence of hypertensive disorders during pregnancy. PMID:25545472

  9. Social stress-enhanced severity of Citrobacter rodentium-induced colitis is CCL2-dependent and attenuated by probiotic Lactobacillus reuteri.

    PubMed

    Mackos, A R; Galley, J D; Eubank, T D; Easterling, R S; Parry, N M; Fox, J G; Lyte, M; Bailey, M T

    2016-03-01

    Psychological stressors are known to affect colonic diseases but the mechanisms by which this occurs, and whether probiotics can prevent stressor effects, are not understood. Because inflammatory monocytes that traffic into the colon can exacerbate colitis, we tested whether CCL2, a chemokine involved in monocyte recruitment, was necessary for stressor-induced exacerbation of infectious colitis. Mice were exposed to a social disruption stressor that entails repeated social defeat. During stressor exposure, mice were orally challenged with Citrobacter rodentium to induce a colonic inflammatory response. Exposure to the stressor during challenge resulted in significantly higher colonic pathogen levels, translocation to the spleen, increases in colonic macrophages, and increases in inflammatory cytokines and chemokines. The stressor-enhanced severity of C. rodentium-induced colitis was not evident in CCL2(-/-) mice, indicating the effects of the stressor are CCL2-dependent. In addition, we tested whether probiotic intervention could attenuate stressor-enhanced infectious colitis by reducing monocyte/macrophage accumulation. Treating mice with probiotic Lactobacillus reuteri reduced CCL2 mRNA levels in the colon and attenuated stressor-enhanced infectious colitis. These data demonstrate that probiotic L. reuteri can prevent the exacerbating effects of stressor exposure on pathogen-induced colitis, and suggest that one mechanism by which this occurs is through downregulation of the chemokine CCL2.

  10. Selected prfA* mutations in recombinant attenuated Listeria monocytogenes strains augment expression of foreign immunogens and enhance vaccine-elicited humoral and cellular immune responses.

    PubMed

    Yan, Lin; Qiu, Jin; Chen, Jianbo; Ryan-Payseur, Bridgett; Huang, Dan; Wang, Yunqi; Rong, Lijun; Melton-Witt, Jody A; Freitag, Nancy E; Chen, Zheng W

    2008-08-01

    While recombinant Listeria monocytogenes strains can be explored as vaccine candidates, it is important to develop attenuated but highly immunogenic L. monocytogenes vaccine vectors. Here, prfA* mutations selected on the basis of upregulated expression of L. monocytogenes PrfA-dependent genes and proteins were assessed to determine their abilities to augment expression of foreign immunogens in recombinant L. monocytogenes vectors and therefore enhance vaccine-elicited immune responses (a prfA* mutation is a mutation that results in constitutive overexpression of PrfA and PrfA-dependent virulence genes; the asterisk distinguishes the mutation from inactivation or stop mutations). A total of 63 recombinant L. monocytogenes vaccine vectors expressing seven individual viral or bacterial immunogens each in nine different L. monocytogenes strains carrying wild-type prfA or having prfA* mutations were constructed and investigated. Mutations selected on the basis of increased PrfA activation in recombinant L. monocytogenes prfA* vaccine vectors augmented expression of seven individual protein immunogens remarkably. Consistently, prime and boost vaccination studies with mice indicated that the prfA(G155S) mutation in recombinant L. monocytogenes DeltaactA prfA* strains enhanced vaccine-elicited cellular immune responses. Surprisingly, the prfA(G155S) mutation was found to enhance vaccine-elicited humoral immune responses as well. The highly immunogenic recombinant L. monocytogenes DeltaactA prfA* vaccine strains were as attenuated as the recombinant parent L. monocytogenes DeltaactA vaccine vector. Thus, recombinant attenuated L. monocytogenes DeltaactA prfA* vaccine vectors potentially are better antimicrobial and anticancer vaccines.

  11. Valuation, Categories and Attributes

    PubMed Central

    Galperin, Inna; Sorenson, Olav

    2014-01-01

    Existing research on categories has only examined indirectly the value associated with being a member of a category relative to the value of the set of attributes that determine membership in that category. This study uses survey data to analyze consumers' preferences for the "organic” label versus for the attributes underlying that label. We found that consumers generally preferred products with the category label to those with the attributes required for the organic label but without the label. We also found that the value accorded to the organic label increased with the number of attributes that an individual associated with the category. Category membership nevertheless still had greater value than even that of the sum of the attributes associated with it. PMID:25111831

  12. Rethinking the Category 'Determiner'

    ERIC Educational Resources Information Center

    Spangler, Wayne E.

    1975-01-01

    The 'determiner' category was originally set up by structuralists for identifying nouns. The rewrite rule for 'determiners' in transformational generative grammar is inadequate for showing correspondences between type and token. An appraisal of quantity terms might eliminate the concept of the 'determiner,' and replace that category with one of…

  13. Categories of Parent Involvement.

    ERIC Educational Resources Information Center

    Bauch, Jerold P.

    1994-01-01

    The growing interest in effective parent involvement has produced several ways to classify or describe ways parents are or should be involved. This article reviews and evaluates Ira Gordon's systems approach, the California-based System Development Corporation's categories, Eugenia H. Berger's parental role categories, Chavkin and Williams' parent…

  14. Categories and Music Transmission

    ERIC Educational Resources Information Center

    Gatien, Greg

    2009-01-01

    Lucy Green's (2008) "Music, Informal Learning, and the School: A New Classroom Pedagogy" gives rise to an interesting corollary. Does the manner of music's transmission inform one's understanding of a musical category? While categories of music can be difficult to define according to strict musical characteristics, a better understanding of…

  15. Brain-selective overexpression of angiotensin-converting enzyme 2 attenuates sympathetic nerve activity and enhances baroreflex function in chronic heart failure.

    PubMed

    Xiao, Liang; Gao, Lie; Lazartigues, Eric; Zucker, Irving H

    2011-12-01

    Angiotensin-converting enzyme 2 (ACE2) has been suggested to be involved in the central regulation of autonomic function. During chronic heart failure (CHF), elevated central angiotensin II signaling contributes to the sustained increase of sympathetic outflow. This is accompanied by a downregulation of ACE2 in the brain. We hypothesized that central overexpression of ACE2 decreases sympathetic outflow and enhances baroreflex function in CHF. Transgenic mice overexpressing human ACE2 selectively in the brain (SYN-hACE2 [SA]) and wild-type littermates (WT) were used. CHF was induced by permanent coronary artery ligation. Four weeks after coronary artery ligation, both WT and SA mice exhibited a significant decrease in left ventricular ejection fraction (<40%). A slight decrease in mean arterial pressure was found only in SA mice. Compared with WT mice with CHF, brain-selective ACE2 overexpression attenuated left ventricular end-diastolic pressure; decreased urinary norepinephrine excretion; baseline renal sympathetic nerve activity (WT CHF: 71.6±7.6% max versus SA CHF: 49.3±6.1% max); and enhanced baroreflex sensitivity (maximum slope: WT sham: 1.61±0.16%/mm Hg versus SA CHF: 1.51±0.17%/mm Hg). Chronic subcutaneous blockade of mas receptor increased renal sympathetic nerve activity in SA mice with CHF (A779: 67.3±5.8% versus vehicle: 46.4±3.6% of max). An upregulation in angiotensin II type 1 receptor expression was detected in medullary nuclei in WT CHF mice, which was significantly attenuated in SA mice with CHF. These data suggest that central ACE2 overexpression exerts a potential protective effect in CHF through attenuating sympathetic outflow. The mechanism for this effect involves angiotensin (1-7) mas signaling, as well as a decrease in angiotensin II type 1 receptor signaling in the medulla.

  16. Attenuation by d-limonene of sodium chloride-enhanced gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats.

    PubMed

    Yano, H; Tatsuta, M; Iishi, H; Baba, M; Sakai, N; Uedo, N

    1999-08-27

    The effects of prolonged administration of d-limonene, a monocyclic monoterpene, on sodium chloride-enhanced induction of gastric carcinogenesis by N-methyl-N'-nitro-N-nitrosoguanidine, the labeling and apoptotic indices, and ornithine decarboxylase (ODC) activity of gastric cancers were investigated in Wistar rats. After 25 weeks of carcinogen treatment, rats were given chow pellets containing 10% sodium chloride and 1% limonene ad libitum. In week 52, the incidence of gastric cancers, the labeling index and ODC activity were significantly higher and the apoptotic index was significantly lower in rats given sodium chlolide than in untreated control rats. However, in rats given both sodium chloride and d-limonene, the incidence of gastric cancers, the labeling index and ODC activity were significantly lower and the apoptotic index was significantly higher than in rats given sodium chloride alone. Our findings suggest that limonene attenuates the gastric carcinogenesis enhanced by sodium chloride via increased apoptosis and decreased ODC activity in gastric cancers.

  17. Phloroglucinol attenuates motor functional deficits in an animal model of Parkinson's disease by enhancing Nrf2 activity.

    PubMed

    Ryu, Junghwa; Zhang, Rui; Hong, Bo-Hyun; Yang, Eun-Jung; Kang, Kyoung Ah; Choi, Moonseok; Kim, Ki Cheon; Noh, Su-Jin; Kim, Hee Soo; Lee, Nam-Ho; Hyun, Jin Won; Kim, Hye-Sun

    2013-01-01

    In this study, we investigated whether phloroglucinol (1,3,5-trihydroxybenzene) has therapeutic effects in cellular and animal model of Parkinson's disease (PD). PD is the second most common, chronic and progressive neurodegenerative disease, and is clinically characterized with motor dysfunctions such as bradykinesia, rigidity, postural instability, gait impairment, and resting tremor. In the brains of PD patients, dopaminergic neuronal loss is observed in the Substantia nigra. Although the exact mechanisms underlying PD are largely unknown, mitochondrial dysfunction and oxidative stress are thought to be critical factors that induce the onset of the disease. Here, phloroglucinol administration was shown to attenuate motor functional deficits evaluated with rota-rod and apomorphine-induced rotation tests in 6-hydroxydopamine (6-OHDA)-induced PD animal models. Moreover, phloroglucinol ameliorated the loss of synapses as assessed with protein levels and immunoreactivity against synaptophysin in the midbrain region of the 6-OHDA-lesioned rats. In addition, in SH-SY5Y cultures, the cytotoxicity of 6-OHDA was reduced by pre-treatment with phloroglucinol. The increase in the reactive oxygen species, lipid peroxidation, protein carbonyl formation and 8-hydroxyguanine caused by treatment with 6-OHDA was attenuated by phloroglucinol in SH-SY5Y cells. Furthermore, phloroglucinol treatment rescued the reduced levels of nuclear Nrf2, antioxidant enzymes, i.e., catalase and glutathione peroxidase, in 6-OHDA-treated cells. Taken together, phloroglucinol has a therapeutic potential for treatment of PD.

  18. Phloroglucinol Attenuates Motor Functional Deficits in an Animal Model of Parkinson's Disease by Enhancing Nrf2 Activity

    PubMed Central

    Hong, Bo-Hyun; Yang, Eun-Jung; Kang, Kyoung Ah; Choi, Moonseok; Kim, Ki Cheon; Noh, Su-Jin; Kim, Hee Soo; Lee, Nam-Ho; Hyun, Jin Won; Kim, Hye-Sun

    2013-01-01

    In this study, we investigated whether phloroglucinol (1, 3, 5 - trihydroxybenzene) has therapeutic effects in cellular and animal model of Parkinson's disease (PD). PD is the second most common, chronic and progressive neurodegenerative disease, and is clinically characterized with motor dysfunctions such as bradykinesia, rigidity, postural instability, gait impairment, and resting tremor. In the brains of PD patients, dopaminergic neuronal loss is observed in the Substantia nigra. Although the exact mechanisms underlying PD are largely unknown, mitochondrial dysfunction and oxidative stress are thought to be critical factors that induce the onset of the disease. Here, phloroglucinol administration was shown to attenuate motor functional deficits evaluated with rota-rod and apomorphine-induced rotation tests in 6-hydroxydopamine (6-OHDA)-induced PD animal models. Moreover, phloroglucinol ameliorated the loss of synapses as assessed with protein levels and immunoreactivity against synaptophysin in the midbrain region of the 6-OHDA-lesioned rats. In addition, in SH-SY5Y cultures, the cytotoxicity of 6-OHDA was reduced by pre-treatment with phloroglucinol. The increase in the reactive oxygen species, lipid peroxidation, protein carbonyl formation and 8-hydroxyguanine caused by treatment with 6-OHDA was attenuated by phloroglucinol in SH-SY5Y cells. Furthermore, phloroglucinol treatment rescued the reduced levels of nuclear Nrf2, antioxidant enzymes, i.e., catalase and glutathione peroxidase, in 6-OHDA-treated cells. Taken together, phloroglucinol has a therapeutic potential for treatment of PD. PMID:23976995

  19. Winter day lengths enhance T lymphocyte phenotypes, inhibit cytokine responses, and attenuate behavioral symptoms of infection in laboratory rats.

    PubMed

    Prendergast, Brian J; Kampf-Lassin, August; Yee, Jason R; Galang, Jerome; McMaster, Nicholas; Kay, Leslie M

    2007-11-01

    Annual variations in day length (photoperiod) trigger changes in the immune and reproductive system of seasonally-breeding animals. The purpose of this study was to determine whether photoperiodic changes in immunity depend on concurrent photoperiodic responses in the reproductive system, or whether immunological responses to photoperiod occur independent of reproductive responses. Here we report photoperiodic changes in enumerative, functional, and behavioral aspects of the immune system, and in immunomodulatory glucocorticoid secretion, in reproductively non-photoperiodic Wistar rats. T-cell numbers (CD3+, CD8+, CD8+CD25+, CD4+CD25+) were higher in the blood of rats housed in short as opposed to long-day lengths for 10 weeks. Following a simulated bacterial infection (Escherichia coli LPS; 125 microg/kg) the severity of several acute-phase sickness behaviors (anorexia, cachexia, neophobia, and social withdrawal) were attenuated in short days. LPS-stimulated IL-1beta and IL-6 production were comparable between photoperiods, but plasma TNFalpha was higher in long-day relative to short-day rats. In addition, corticosterone concentrations were higher in short-day relative to long-day rats. The data are consistent with the hypothesis that photoperiodic regulation of the immune system can occur entirely independently of photoperiodic regulation of the reproductive system. In the absence of concurrent reproductive responses, short days increase the numbers of leukocytes capable of immunosurveillance and inhibition of inflammatory responses, increase proinflammatory cytokine production, increase immunomodulatory glucocorticoid secretion, and ultimately attenuate behavioral responses to infection. Seasonal changes in the host immune system, endocrine system, and behavior may contribute to the seasonal variability in disease outcomes, even in reproductively non-photoperiodic mammals.

  20. A Brucella melitensis M5-90 wboA deletion strain is attenuated and enhances vaccine efficacy.

    PubMed

    Li, Zhi-Qiang; Shi, Jing-Xue; Fu, Wen-Dong; Zhang, Yu; Zhang, Jing; Wang, Zhen; Li, Tian-Sen; Chen, Chuang-Fu; Guo, Fei; Zhang, Hui

    2015-08-01

    Brucella spp. are Gram-negative intracellular pathogens of both humans and animals that cause great economic burdens in developing countries. Live attenuated vaccines are the most efficient means for the prevention and control of animal Brucellosis. However, Brucella vaccines (strain M5-90 and others) have several drawbacks and do not allow serological differentiation between vaccinated and infected animals. A wboA mutant was derived from Brucella melitensis (B. melitensis) vaccine strain M5-90 and tested for virulence and protective efficiency. T-cell responses (CD4(+), CD8(+)), levels of immunoglobulin G (IgG), and cytokine production were observed. WboA was also assessed as a diagnostic marker for Brucellosis. B. melitensis strain M5-90ΔwboA exhibited reduced survival in murine macrophages (RAW 264.7) and BALB/c mice and induced protective immunity in mice comparable to that from the parental strain M5-90. In mice, the wboA mutant elicited an anti-Brucella-specific IgG response and induced the secretion of gamma interferon (IFN-γ) and interleukin-2 (IL-2). In sheep, M5-90ΔwboA immunization induced the secretion of IFN-γ, and serum samples from sheep inoculated with M5-90ΔwboA were negative by Bengal Plate Test (RBPT) and Standard Tube Agglutination Test (STAT). In mice, probes against WboA antigen allowed for serological differentiation between natural infection and vaccination. The M5-90ΔwboA mutant is a potential attenuated live vaccine candidate against virulent B. melitensis 16M infection. It will be further evaluated in livestock.

  1. A tryptamine-derived catecholaminergic enhancer, (-)-1-(benzofuran-2-yl)-2-propylaminopentane [(-)-BPAP], attenuates reinstatement of methamphetamine-seeking behavior in rats.

    PubMed

    Hiranita, T; Yamamoto, T; Nawata, Y

    2010-01-20

    Relapse to drug craving is problematic in treatment for drug abuse. Evidence suggests inactivation of dopaminergic neurotransmission during drug withdrawal. Meanwhile, a tryptamine analogue, (-)-1-(benzofuran-2-yl)-2-propylaminopentane [(-)-BPAP], has been reported to enhance electrical stimulation of monoamine release. This study examined the effect of (-)-BPAP on reinstatement of methamphetamine-seeking behavior in an animal model of relapse to drug abuse. Rats were trained to i.v. self-administer methamphetamine paired with a light and tone (methamphetamine-associated cues) under a fixed-ratio 1 schedule of reinforcement for 10 days. After extinction session under saline infusions without cues, a reinstatement test under saline infusions was begun. Reinstatement induced by methamphetamine-associated cues or methamphetamine-priming injections was attenuated by repeated administration of (-)-BPAP during the extinction phase. Acute administration of (-)-BPAP on test day dose-dependently attenuated both reinstatements. Acute administration of (-)-BPAP neither reinstated methamphetamine-seeking behavior alone nor affected methamphetamine self-administration. Pretreatment with either R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine (SCH-23390), a dopamine D(1)-like receptor antagonist, or amisulpride, a dopamine D(2)-like receptor antagonist, did not appreciably affected the acute effect of (-)-BPAP on both reinstatements. Co-pretreatment with the dopamine receptor antagonists failed to alter the effects of (-)-BPAP. Meanwhile, pretreatment with a dopamine D(1)-like receptor agonist, (+/-)-6-chloro-7,8-dihydroxy-l-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide (SKF-81297), dose-dependently attenuated reinstatement induced by the cues or methamphetamine-priming injections. In contrast to (-)-BPAP, pretreatment with SCH-23390 reversed the effects of SKF-81297. Our findings suggest activation of dopamine D(1)-like receptors results

  2. PRELIMINARY DATA REPORT: HUMATE INJECTION AS AN ENHANCED ATTENUATION METHOD AT THE F-AREA SEEPAGE BASINS, SAVANNAH RIVER SITE

    SciTech Connect

    Millings, M.

    2013-09-16

    A field test of a humate technology for uranium and I-129 remediation was conducted at the F-Area Field Research Site as part of the Attenuation-Based Remedies for the Subsurface Applied Field Research Initiative (ABRS AFRI) funded by the DOE Office of Soil and Groundwater Remediation. Previous studies have shown that humic acid sorbed to sediments strongly binds uranium at mildly acidic pH and potentially binds iodine-129 (I-129). Use of humate could be applicable for contaminant stabilization at a wide variety of DOE sites however pilot field-scale tests and optimization of this technology are required to move this technical approach from basic science to actual field deployment and regulatory acceptance. The groundwater plume at the F-Area Field Research Site contains a large number of contaminants, the most important from a risk perspective being strontium-90 (Sr-90), uranium isotopes, I-129, tritium, and nitrate. Groundwater remains acidic, with pH as low as 3.2 near the basins and increasing to the background pH of approximately 5at the plume fringes. The field test was conducted in monitoring well FOB 16D, which historically has shown low pH and elevated concentrations of Sr-90, uranium, I-129 and tritium. The field test included three months of baseline monitoring followed by injection of a potassium humate solution and approximately four and half months of post monitoring. Samples were collected and analyzed for numerous constituents but the focus was on attenuation of uranium, Sr-90, and I-129. This report provides background information, methodology, and preliminary field results for a humate field test. Results from the field monitoring show that most of the excess humate (i.e., humate that did not sorb to the sediments) has flushed through the surrounding formation. Furthermore, the data indicate that the test was successful in loading a band of sediment surrounding the injection point to a point where pH could return to near normal during the study

  3. LcrV delivered via type III secretion system of live attenuated Yersinia pseudotuberculosis enhances immunogenicity against pneumonic plague.

    PubMed

    Sun, Wei; Sanapala, Shilpa; Henderson, Jeremy C; Sam, Shandiin; Olinzock, Joseph; Trent, M Stephen; Curtiss, Roy

    2014-10-01

    Here, we constructed a Yersinia pseudotuberculosis mutant strain with arabinose-dependent regulated and delayed shutoff of crp expression (araC P(BAD) crp) and replacement of the msbB gene with the Escherichia coli msbB gene to attenuate it. Then, we inserted the asd mutation into this construction to form χ10057 [Δasd-206 ΔmsbB868::P(msbB) msbB(EC) ΔP(crp21)::TT araC P(BAD) crp] for use with a balanced-lethal Asd-positive (Asd(+)) plasmid to facilitate antigen synthesis. A hybrid protein composed of YopE (amino acids [aa]1 to 138) fused with full-length LcrV (YopE(Nt138)-LcrV) was synthesized in χ10057 harboring an Asd(+) plasmid (pYA5199, yopE(Nt138)-lcrV) and could be secreted through a type III secretion system (T3SS) in vitro and in vivo. Animal studies indicated that mice orally immunized with χ10057(pYA5199) developed titers of IgG response to whole-cell lysates of Y. pestis (YpL) and subunit LcrV similar to those seen with χ10057(pYA3332) (χ10057 plus an empty plasmid). However, only immunization of mice with χ10057(pYA5199) resulted in a significant secretory IgA response to LcrV. χ10057(pYA5199) induced a higher level of protection (80% survival) against intranasal (i.n.) challenge with ~240 median lethal doses (LD50) (2.4 × 10(4) CFU) of Y. pestis KIM6+(pCD1Ap) than χ10057(pYA3332) (40% survival). Splenocytes from mice vaccinated with χ10057(pYA5199) produced significant levels of gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), and interleukin-17 (IL-17) after restimulation with LcrV and YpL antigens. Our results suggest that it is possible to use an attenuated Y. pseudotuberculosis strain delivering the LcrV antigen via the T3SS as a potential vaccine candidate against pneumonic plague.

  4. Mycobacterium tuberculosis PE_PGRS18 enhances the intracellular survival of M. smegmatis via altering host macrophage cytokine profiling and attenuating the cell apoptosis.

    PubMed

    Yang, Wenmin; Deng, Wanyan; Zeng, Jie; Ren, Sai; Ali, Md Kaisar; Gu, Yinzhong; Li, Yangyuling; Xie, Jianping

    2017-04-01

    Mycobacterium tuberculosis PE/PPE family proteins, named after the presence of conserved PE (Pro-Glu) and PPE (Pro-Pro-Glu) domains at N-terminal, are prevalent in M. tuberculosis genome. The function of most PE/PPE family proteins remains elusive. To characterize the function of PE_PGRS18, the encoding gene was heterologously expressed in M. smegmatis, a nonpathogenic mycobacterium. The recombinant PE_PGRS18 is cell wall associated. M. smegmatis PE_PGRS18 recombinant showed differential response to stresses and altered the production of host cytokines IL-6, IL-1β, IL-12p40 and IL-10, as well as enhanced survival within macrophages largely via attenuating the apoptosis of macrophages. In summary, the study firstly unveiled the role of PE_PGRS18 in physiology and pathogenesis of mycobacterium.

  5. Epigenetic Upregulation of Metallothionein 2A by Diallyl Trisulfide Enhances Chemosensitivity of Human Gastric Cancer Cells to Docetaxel Through Attenuating NF-κB Activation

    PubMed Central

    Pan, Yuanming; Lin, Shuye; Xing, Rui; Zhu, Min; Lin, Bonan; Cui, Jiantao; Li, Wenmei; Gao, Jing; Shen, Lin; Zhao, Yuanyuan; Guo, Mingzhou; Wang, Ji Ming

    2016-01-01

    Abstract Aims: Metallothionein 2A (MT2A) and nuclear factor-kappaB (NF-κB) are both involved in carcinogenesis and cancer chemosensitivity. We previously showed decreased expression of MT2A and IκB-α in human gastric cancer (GC) associated with poor prognosis of GC patients. The present study investigated the effect of diallyl trisulfide (DATS), a garlic-derived compound, and docetaxel (DOC) on regulation of MT2A in relation to NF-κB in GC cells. Results: DATS attenuated NF-κB signaling in GC cells, resulting in G2/M cell cycle arrest and apoptosis, culminating in the inhibition of cell proliferation and tumorigenesis in nude mice. The anti-GC effect of DATS was attributable to its capacity to epigenetically upregulate MT2A, which in turn enhanced transcription of IκB-α to suppress NF-κB activation in GC cells. The combination of DATS with DOC exhibited a synergistic anti-GC activity accompanied by MT2A upregulation and NF-κB inactivation. Histopathologic analysis of GC specimens from patients showed a significant increase in MT2A expression following DOC treatment. GC patients with high MT2A expression in tumor specimens showed significantly improved response to chemotherapy and prolonged survival compared with those with low MT2A expression in tumors. Innovation and Conclusion: We conclude that DATS exerts its anti-GC activity and enhances chemosensitivity of GC to DOC by epigenetic upregulation of MT2A to attenuate NF-κB signaling. Our findings delineate a mechanistic basis of MT2A/NF-κB signaling for DATS- and DOC-mediated anti-GC effects, suggesting that MT2A may be a chemosensitivity indicator in GC patients receiving DOC-based treatment and a promising target for more effective treatment of GC by combination of DATS and DOC. Antioxid. Redox Signal. 24, 839–854. PMID:26801633

  6. RGD Peptide Cell-Surface Display Enhances the Targeting and Therapeutic Efficacy of Attenuated Salmonella-mediated Cancer Therapy.

    PubMed

    Park, Seung-Hwan; Zheng, Jin Hai; Nguyen, Vu Hong; Jiang, Sheng-Nan; Kim, Dong-Yeon; Szardenings, Michael; Min, Jung Hyun; Hong, Yeongjin; Choy, Hyon E; Min, Jung-Joon

    2016-01-01

    Bacteria-based anticancer therapies aim to overcome the limitations of current cancer therapy by actively targeting and efficiently removing cancer. To achieve this goal, new approaches that target and maintain bacterial drugs at sufficient concentrations during the therapeutic window are essential. Here, we examined the tumor tropism of attenuated Salmonella typhimurium displaying the RGD peptide sequence (ACDCRGDCFCG) on the external loop of outer membrane protein A (OmpA). RGD-displaying Salmonella strongly bound to cancer cells overexpressing αvβ3, but weakly bound to αvβ3-negative cancer cells, suggesting the feasibility of displaying a preferential homing peptide on the bacterial surface. In vivo studies revealed that RGD-displaying Salmonellae showed strong targeting efficiency, resulting in the regression in αvβ3-overexpressing cancer xenografts, and prolonged survival of mouse models of human breast cancer (MDA-MB-231) and human melanoma (MDA-MB-435). Thus, surface engineering of Salmonellae to display RGD peptides increases both their targeting efficiency and therapeutic effect.

  7. Light attenuates lipid accumulation while enhancing cell proliferation and starch synthesis in the glucose-fed oleaginous microalga Chlorella zofingiensis

    PubMed Central

    Chen, Tianpeng; Liu, Jin; Guo, Bingbing; Ma, Xiaonian; Sun, Peipei; Liu, Bin; Chen, Feng

    2015-01-01

    The objective of this study was to investigate the effect of light on lipid and starch accumulation in the oleaginous green algae Chlorella zofingiensis supplemented with glucose. C. zofingiensis, when fed with 30 g/L glucose, synthesized lipids up to 0.531 g/g dry weight; while in the presence of light, the lipid content dropped down to 0.352 g/g dry weight. Lipid yield on glucose was 0.184 g/g glucose, 14% higher than that cultured with light. The light-mediated lipid reduction was accompanied by the down-regulation of fatty acid biosynthetic genes at the transcriptional level. Furthermore, light promoted cell proliferation, starch accumulation, and the starch yield based on glucose. Taken together, light may attenuate lipid accumulation, possibly through the inhibition of lipid biosynthetic pathway, leading to more carbon flux from glucose to starch. This study reveals the dual effects of light on the sugar-fed C. zofingiensis and provides valuable insights into the possible optimization of algal biomass and lipid production by manipulation of culture conditions. PMID:26442783

  8. Light attenuates lipid accumulation while enhancing cell proliferation and starch synthesis in the glucose-fed oleaginous microalga Chlorella zofingiensis.

    PubMed

    Chen, Tianpeng; Liu, Jin; Guo, Bingbing; Ma, Xiaonian; Sun, Peipei; Liu, Bin; Chen, Feng

    2015-10-07

    The objective of this study was to investigate the effect of light on lipid and starch accumulation in the oleaginous green algae Chlorella zofingiensis supplemented with glucose. C. zofingiensis, when fed with 30 g/L glucose, synthesized lipids up to 0.531 g/g dry weight; while in the presence of light, the lipid content dropped down to 0.352 g/g dry weight. Lipid yield on glucose was 0.184 g/g glucose, 14% higher than that cultured with light. The light-mediated lipid reduction was accompanied by the down-regulation of fatty acid biosynthetic genes at the transcriptional level. Furthermore, light promoted cell proliferation, starch accumulation, and the starch yield based on glucose. Taken together, light may attenuate lipid accumulation, possibly through the inhibition of lipid biosynthetic pathway, leading to more carbon flux from glucose to starch. This study reveals the dual effects of light on the sugar-fed C. zofingiensis and provides valuable insights into the possible optimization of algal biomass and lipid production by manipulation of culture conditions.

  9. Troxerutin Attenuates Enhancement of Hepatic Gluconeogenesis by Inhibiting NOD Activation-Mediated Inflammation in High-Fat Diet-Treated Mice

    PubMed Central

    Zhang, Zifeng; Wang, Xin; Zheng, Guihong; Shan, Qun; Lu, Jun; Fan, Shaohua; Sun, Chunhui; Wu, Dongmei; Zhang, Cheng; Su, Weitong; Sui, Junwen; Zheng, Yuanlin

    2016-01-01

    Recent evidence suggests that troxerutin, a trihydroxyethylated derivative of natural bioflavonoid rutin, exhibits beneficial effects on diabetes-related symptoms. Here we investigated the effects of troxerutin on the enhancement of hepatic gluconeogenesis in high-fat diet (HFD)-treated mice and the mechanisms underlying these effects. Mice were divided into four groups: Control group, HFD group, HFD + Troxerutin group, and Troxerutin group. Troxerutin was treated by daily oral administration at doses of 150 mg/kg/day for 20 weeks. Tauroursodeoxycholic acid (TUDCA) was used to inhibit endoplasmic reticulum stress (ER stress). Our results showed that troxerutin effectively improved obesity and related metabolic parameters, and liver injuries in HFD-treated mouse. Furthermore, troxerutin significantly attenuated enhancement of hepatic gluconeogenesis in HFD-fed mouse. Moreover, troxerutin notably suppressed nuclear factor-κB (NF-κB) p65 transcriptional activation and release of inflammatory cytokines in HFD-treated mouse livers. Mechanismly, troxerutin dramatically decreased Nucleotide oligomerization domain (NOD) expression, as well as interaction between NOD1/2 with interacting protein-2 (RIP2), by abating oxidative stress-induced ER stress in HFD-treated mouse livers, which was confirmed by TUDCA treatment. These improvement effects of troxerutin on hepatic glucose disorders might be mediated by its anti-obesity effect. In conclusion, troxerutin markedly diminished HFD-induced enhancement of hepatic gluconeogenesis via its inhibitory effects on ER stress-mediated NOD activation and consequent inflammation, which might be mediated by its anti-obesity effect. PMID:28029143

  10. Attenuation of polyglutamine-induced toxicity by enhancement of mitochondrial OXPHOS in yeast and fly models of aging

    PubMed Central

    Ruetenik, Andrea L.; Ocampo, Alejandro; Ruan, Kai; Zhu, Yi; Li, Chong; Zhai, R. Grace; Barrientos, Antoni

    2016-01-01

    Defects in mitochondrial biogenesis and function are common in many neurodegenerative disorders, including Huntington’s disease (HD). We have previously shown that in yeast models of HD, enhancement of mitochondrial biogenesis through overexpression of Hap4, the catalytic subunit of the transcriptional complex that regulates mitochondrial gene expression, alleviates the growth arrest induced by expanded polyglutamine (polyQ) tract peptides in rapidly dividing cells. However, the mechanism through which HAP4 overexpression exerts this protection remains unclear. Furthermore, it remains unexplored whether HAP4 overexpression and increased respiratory function during growth can also protect against polyQ-induced toxicity during yeast chronological lifespan. Here, we show that in yeast, mitochondrial respiration and oxidative phosphorylation (OXPHOS) are essential for protection against the polyQ-induced growth defect by HAP4 overexpression. In addition, we show that not only increased HAP4 levels, but also alternative interventions, including calorie restriction, that result in enhanced mitochondrial biogenesis confer protection against polyQ toxicity during stationary phase. The data obtained in yeast models guided experiments in a fly model of HD, where we show that enhancement of mitochondrial biogenesis can also protect against neurodegeneration and behavioral deficits. Our results suggest that therapeutic interventions aiming at the enhancement of mitochondrial respiration and OXPHOS could reduce polyQ toxicity and delay disease onset. PMID:28357370

  11. Ebselen attenuates oxidative DNA damage and enhances its repair activity in the thalamus after focal cortical infarction in hypertensive rats.

    PubMed

    He, Meixia; Xing, Shihui; Yang, Bo; Zhao, Liqun; Hua, Haiying; Liang, Zhijian; Zhou, Wenliang; Zeng, Jinsheng; Pei, Zhong

    2007-11-21

    Oxidative DNA damage has been proposed to be a major contributor to focal cerebral ischemic injury. However, little is known about the role of oxidative DNA damage in remote damage secondary to the primary infarction. In the present study, we investigated oxidative damage within the ventroposterior nucleus (VPN) after distal middle cerebral artery occlusion (MCAO) in hypertensive rats. We also examined the possible protective effect of ebselen, one glutathione peroxidase mimic, on delayed degeneration in the VPN after distal MCAO. Neuronal damage in the ipsilateral VPN was examined by Nissl staining. Oxidative DNA damage and base repair enzyme activity were assessed by analyzing immunoreactivity of 8-hydroxy-2'-deoxyguanosine (8-ohdG) and 8-oxoguanine DNA glycosylase (OGG1), respectively. The number of intact neurons in the ipsilateral VPN decreased by 52% compared to the contralateral side in ischemia group 2 weeks after distal cerebral cortical infarction. The immunoreactivity of 8-ohdG significantly increased while OGG1 immunoreactivity significantly decreased in the ipsilateral VPN 2 weeks after distal cortical infarction (all p<0.01). Compared with vehicle treatment, ebselen significantly attenuated the neuron loss, ameliorated ischemia-induced increase in 8-ohdG level as well as decrease in OGG1 level within the ipsilateral VPN (all p<0.01). OGG1 was further demonstrated to mainly express in neurons. These findings strongly suggest that oxidative DNA damage may be involved in the delayed neuronal death in the VPN region following distal MCAO. Furthermore, ebselen protects against the delayed damage in the VPN when given at 24 h following distal MCAO.

  12. Restricted Inter-ocean Exchange and Attenuated Biological Export Caused Enhanced Carbonate Preservation in the PETM Ocean

    NASA Astrophysics Data System (ADS)

    Luo, Y.; Boudreau, B. P.; Dickens, G. R.; Sluijs, A.; Middelburg, J. J.

    2015-12-01

    Carbon dioxide (CO2) release during the Paleocene-Eocene Thermal Maximum (PETM, 55.8 Myr BP) acidified the oceans, causing a decrease in calcium carbonate (CaCO3) preservation. During the subsequent recovery from this acidification, the sediment CaCO3 content came to exceed pre-PETM values, known as over-deepening or over-shooting. Past studies claim to explain these trends, but have failed to reproduce quantitatively the time series of CaCO3 preservation. We employ a simple biogeochemical model to recreate the CaCO3 records preserved at Walvis Ridge of the Atlantic Ocean. Replication of the observed changes, both shallowing and the subsequent over-deepening, requires two conditions not previously considered: (1) limited deep-water exchange between the Indo-Atlantic and Pacific oceans and (2) a ~50% reduction in the export of CaCO3 to the deep sea during acidification. Contrary to past theories that attributed over-deepening to increased riverine alkalinity input, we find that over-deepening is an emergent property, generated at constant riverine input when attenuation of CaCO3 export causes an unbalanced alkalinity input to the deep oceans (alkalinization) and the development of deep super-saturation. Restoration of CaCO3 export, particularly in the super-saturated deep Indo-Atlantic ocean, later in the PETM leads to greater accumulation of carbonates, ergo over-shooting, which returns the ocean to pre-PETM conditions over a time scale greater than 200 kyr. While this feedback between carbonate export and the riverine input has not previously been considered, it appears to constitute an important modification of the classic carbonate compensation concept used to explain oceanic response to acidification.

  13. Hyperbaric oxygen preconditioning attenuates hyperglycemia-enhanced hemorrhagic transformation by inhibiting matrix metalloproteinases in focal cerebral ischemia in rats.

    PubMed

    Soejima, Yoshiteru; Hu, Qin; Krafft, Paul R; Fujii, Mutsumi; Tang, Jiping; Zhang, John H

    2013-09-01

    Hyperglycemia dramatically aggravates brain infarct and hemorrhagic transformation (HT) after ischemic stroke. Oxidative stress and matrix metalloproteinases (MMPs) play an important role in the pathophysiology of HT. Hyperbaric oxygen preconditioning (HBO-PC) has been proved to decrease oxidative stress and has been demonstrated to be neuroprotective in experimental stroke models. The present study determined whether HBO-PC would ameliorate HT by a pre-ischemic increase of reactive oxygen species (ROS) generation, and a suppression of MMP-2 and MMP-9 in hyperglycemic middle cerebral artery occlusion (MCAO) rats. Rats were pretreated with HBO (100% O₂, 2.5 atmosphere absolutes) 1 h daily for 5 days before MCAO. Acute hyperglycemia was induced by an injection of 50% dextrose. Neurological deficits, infarction volume and hemorrhagic volume were assessed 24 h and 7 days after ischemia. ROS scavenger n-acetyl cysteine (NAC), hypoxia-inducible factor-1α (HIF-1α), inhibitor 2-methoxyestradiol (2ME2) and activator cobalt chloride (CoCl₂), and MMP inhibitor SB-3CT were administrated for mechanism study. The activity of MMP-2 and MMP-9, and the expression HIF-1α were measured. HBO-PC improved neurological deficits, and reduced hemorrhagic volume; the expression of HIF-1α was significantly decreased, and the activity of MMP-2 and MMP-9 was reduced by HBO-PC compared with vehicle group. Our results suggested that HBO-PC attenuated HT via decreasing HIF-1α and its downstream MMP-2 and MMP-9 in hyperglycemic MCAO rats.

  14. Consumer Product Category Database

    EPA Pesticide Factsheets

    The Chemical and Product Categories database (CPCat) catalogs the use of over 40,000 chemicals and their presence in different consumer products. The chemical use information is compiled from multiple sources while product information is gathered from publicly available Material Safety Data Sheets (MSDS). EPA researchers are evaluating the possibility of expanding the database with additional product and use information.

  15. Quantification of traumatic meningeal injury using dynamic contrast enhanced (DCE) fluid-attenuated inversion recovery (FLAIR) imaging

    NASA Astrophysics Data System (ADS)

    Castro, Marcelo A.; Williford, Joshua P.; Cota, Martin R.; MacLaren, Judy M.; Dardzinski, Bernard J.; Latour, Lawrence L.; Pham, Dzung L.; Butman, John A.

    2016-03-01

    Traumatic meningeal injury is a novel imaging marker of traumatic brain injury, which appears as enhancement of the dura on post-contrast T2-weighted FLAIR images, and is likely associated with inflammation of the meninges. Dynamic Contrast Enhanced MRI provides a better discrimination of abnormally perfused regions. A method to properly identify those regions is presented. Images of seventeen patients scanned within 96 hours of head injury with positive traumatic meningeal injury were normalized and aligned. The difference between the pre- and last post-contrast acquisitions was segmented and voxels in the higher class were spatially clustered. Spatial and morphological descriptors were used to identify the regions of enhancement: a) centroid; b) distance to the brain mask from external voxels; c) distance from internal voxels; d) size; e) shape. The method properly identified thirteen regions among all patients. The method failed in one case due to the presence of a large brain lesion that altered the mask boundaries. Most false detections were correctly rejected resulting in a sensitivity and specificity of 92.9% and 93.6%, respectively.

  16. Attenuated allergic airway hyperresponsiveness in C57BL/6 mice is associated with enhanced surfactant protein (SP)-D production following allergic sensitization

    PubMed Central

    Atochina, Elena N; Beers, Michael F; Tomer, Yaniv; Scanlon, Seth T; Russo, Scott J; Panettieri, Reynold A; Haczku, Angela

    2003-01-01

    Background C57BL/6 mice have attenuated allergic airway hyperresponsiveness (AHR) when compared with Balb/c mice but the underlying mechanisms remain unclear. SP-D, an innate immune molecule with potent immunosuppressive activities may have an important modulatory role in the allergic airway response and the consequent physiological changes. We hypothesized that an elevated SP-D production is associated with the impaired ability of C57BL/6 mice to develop allergic AHR. Methods SP-D mRNA and protein expression was investigated during development of allergic airway changes in a model of Aspergillus fumigatus (Af)-induced allergic inflammation. To study whether strain dependency of allergic AHR is associated with different levels of SP-D in the lung, Balb/c and C57BL/6 mice were compared. Results Sensitization and exposure to Af induced significant airway inflammation in both mouse strains in comparison with naïve controls. AHR to acetylcholine however was significantly attenuated in C57BL/6 mice in spite of increased eosinophilia and serum IgE when compared with Balb/c mice (p < 0.05). Af challenge of sensitized C57BL/6 mice induced a markedly increased SP-D protein expression in the SA surfactant fraction (1,894 ± 170% of naïve controls) that was 1.5 fold greater than the increase in Balb/c mice (1,234 ± 121% p < 0.01). These changes were selective since levels of the hydrophobic SP-B and SP-C and the hydrophilic SP-A were significantly decreased following sensitization and challenge with Af in both strains. Further, sensitized and exposed C57BL/6 mice had significantly lower IL-4 and IL-5 in the BAL fluid than that of Balb/c mice (p < 0.05). Conclusions These results suggest that enhanced SP-D production in the lung of C57BL/6 mice may contribute to an attenuated AHR in response to allergic airway sensitization. SP-D may act by inhibiting synthesis of Th2 cytokines. PMID:14748931

  17. Dimethyl fumarate attenuates 6-OHDA-induced neurotoxicity in SH-SY5Y cells and in animal model of Parkinson's disease by enhancing Nrf2 activity.

    PubMed

    Jing, X; Shi, H; Zhang, C; Ren, M; Han, M; Wei, X; Zhang, X; Lou, H

    2015-02-12

    Oxidative stress is central to the pathology of several neurodegenerative diseases, including Parkinson's disease (PD), and therapeutics designed to enhance antioxidant potential could have clinical value. In this study, we investigated whether dimethyl fumarate (DMF) has therapeutic effects in cellular and animal model of PD, and explore the role of nuclear transcription factor related to NF-E2 (Nrf2) in this process. Treatment of animals and dopaminergic SH-SY5Y cells with DMF resulted in increased nuclear levels of active Nrf2, with subsequent upregulation of antioxidant target genes. The cytotoxicity of 6-hydroxydopamine (6-OHDA) was reduced by pre-treatment with DMF in SH-SY5Y cells. The increase in the reactive oxygen species caused by 6-OHDA treatment was also attenuated by DMF in SH-SY5Y cells. The neuroprotective effects of DMF against 6-OHDA neurotoxicity were dependent on Nrf2, since treatment with Nrf2 siRNA failed to block against 6-OHDA neurotoxicity and induce Nrf2-dependent cytoprotective genes in SH-SY5Y cells. In vivo, DMF oral administration was shown to upregulate mRNA and protein levels of Nrf2 and Nrf2-regulated cytoprotective genes, attenuate 6-OHDA induced striatal oxidative stress and inflammation in C57BL/6 mice. Moreover, DMF ameliorated dopaminergic neurotoxicity in 6-OHDA-induced PD animal models as evidenced by amelioration of locomotor dysfunction, loss in striatal dopamine, and reductions in dopaminergic neurons in the substantia nigra and striatum. Taken together, these data strongly suggest that DMF may be beneficial for the treatment of neurodegenerative diseases like PD.

  18. Sound categories or phonemes?

    PubMed

    Redford, Melissa A

    2017-02-01

    Vihman emphasizes the importance of early word production to the emergence of phonological knowledge. This emphasis, consistent with the generative function of phonology, provides insight into the concurrent representation of phonemes and words. At the same time, Vihman's focus on phonology leads her to possibly overstate the influence of early word acquisition on the emergence of sound categories that are probably purely phonetic in nature at the outset of learning.

  19. Cilostazol attenuates ischemic brain injury and enhances neurogenesis in the subventricular zone of adult mice after transient focal cerebral ischemia.

    PubMed

    Tanaka, Y; Tanaka, R; Liu, M; Hattori, N; Urabe, T

    2010-12-29

    Evidence suggests that neurogenesis occurs in the adult mammalian brain, and that various stimuli, for example, ischemia/hypoxia, enhance the generation of neural progenitor cells in the subventricular zone (SVZ) and their migration into the olfactory bulb. In a mouse stroke model, focal ischemia results in activation of neural progenitor cells followed by their migration into the ischemic lesion. The present study assessed the in vivo effects of cilostazol, a type 3 phosphodiesterase inhibitor known to activate the cAMP-responsive element binding protein (CREB) signaling, on neurogenesis in the ipsilateral SVZ and peri-infarct area in a mouse model of transient middle cerebral artery occlusion. Mice were divided into sham operated (n=12), vehicle- (n=18) and cilostazol-treated (n=18) groups. Sections stained for 5-bromodeoxyuridine (BrdU) and several neuronal and a glial markers were analyzed at post-ischemia days 1, 3 and 7. Cilostazol reduced brain ischemic volume (P<0.05) and induced earlier recovery of neurologic deficit (P<0.05). Cilostazol significantly increased the density of BrdU-positive newly-formed cells in the SVZ compared with the vehicle group without ischemia. Increased density of doublecortin (DCX)-positive and BrdU/DCX-double positive neural progenitor cells was noted in the ipsilateral SVZ and peri-infarct area at 3 and 7 days after focal ischemia compared with the vehicle group (P<0.05). Cilostazol increased DCX-positive phosphorylated CREB (pCREB)-expressing neural progenitor cells, and increased brain derived neurotrophic factor (BDNF)-expressing astrocytes in the ipsilateral SVZ and peri-infarct area. The results indicated that cilostazol enhanced neural progenitor cell generation in both ipsilateral SVZ and peri-infarct area through CREB-mediated signaling pathway after focal ischemia.

  20. Sarcosine attenuates toluene-induced motor incoordination, memory impairment, and hypothermia but not brain stimulation reward enhancement in mice

    SciTech Connect

    Chan, Ming-Huan; Chung, Shiang-Sheng; Stoker, Astrid K.; Markou, Athina; Chen, Hwei-Hsien

    2012-12-01

    Toluene, a widely used and commonly abused organic solvent, produces various behavioral disturbances, including motor incoordination and cognitive impairment. Toluene alters the function of a large number of receptors and ion channels. Blockade of N-methyl-D-aspartate (NMDA) receptors has been suggested to play a critical role in toluene-induced behavioral manifestations. The present study determined the effects of various toluene doses on motor coordination, recognition memory, body temperature, and intracranial self-stimulation (ICSS) thresholds in mice. Additionally, the effects of sarcosine on the behavioral and physiological effects induced by toluene were evaluated. Sarcosine may reverse toluene-induced behavioral manifestations by acting as an NMDA receptor co-agonist and by inhibiting the effects of the type I glycine transporter (GlyT1). Mice were treated with toluene alone or combined with sarcosine pretreatment and assessed for rotarod performance, object recognition memory, rectal temperature, and ICSS thresholds. Toluene dose-dependently induced motor incoordination, recognition memory impairment, and hypothermia and lowered ICSS thresholds. Sarcosine pretreatment reversed toluene-induced changes in rotarod performance, novel object recognition, and rectal temperature but not ICSS thresholds. These findings suggest that the sarcosine-induced potentiation of NMDA receptors may reverse motor incoordination, memory impairment, and hypothermia but not the enhancement of brain stimulation reward function associated with toluene exposure. Sarcosine may be a promising compound to prevent acute toluene intoxications by occupational or intentional exposure. -- Highlights: ► Toluene induces impairments in Rotarod test and novel object recognition test. ► Toluene lowers rectal temperature and ICSS thresholds in mice. ► Sarcosine reverses toluene-induced changes in motor, memory and body temperature. ► Sarcosine pretreatment does not affect toluene

  1. Delayed administration of the nucleic acid analog 2Cl-C.OXT-A attenuates brain damage and enhances functional recovery after ischemic stroke.

    PubMed

    Okabe, Naohiko; Nakamura, Emi; Himi, Naoyuki; Narita, Kazuhiko; Tsukamoto, Ikuko; Maruyama, Tokumi; Sakakibara, Norikazu; Nakamura, Takehiro; Itano, Toshifumi; Miyamoto, Osamu

    2013-04-19

    2Cl-C.OXT-A (COA-Cl) is a novel nucleic acid analog that enhances angiogenesis through extracellular signal-regulated kinase 1 or 2 (ERK1/2) activation. ERK1/2 is a well-known kinase that regulates cell survival, proliferation and differentiation in the central nervous system. We performed in vitro and in vivo experiments to investigate whether COA-Cl can attenuate neuronal damage and enhance recovery after brain ischemia. In primary cortical neuron cultures, COA-Cl prevented neuronal injury after 2h of oxygen-glucose deprivation. COA-Cl increased phospho-ERK levels in a dose-dependent manner and COA-Cl-induced neuroprotection and ERK1/2 activation was inhibited by suramin or PD98059. The effect of COA-Cl was evaluated in vivo with 60min of middle cerebral artery occlusion combined with bilateral common carotid artery occlusion. COA-Cl or saline was injected intracerebroventricularly 5min after reperfusion. COA-Cl significantly reduced infarct volume and improved neurological deficits upon injection of 15 or 30μg/kg COA-Cl. Moreover, COA-Cl reduced the number of TUNEL positive cells in ischemic boundary, while rCBF was not significantly changed by COA-Cl administration. We also evaluated the effect of delayed COA-Cl administration on recovery from brain ischemia by continuous administration of COA-Cl from 1 to 8 days after reperfusion. Delayed continuous COA-Cl administration also reduced infarct volume. Furthermore, COA-Cl enhanced peri-infarct angiogenesis and synaptogenesis, resulting in improved motor function recovery. Our findings demonstrate that COA-Cl exerts both neuroprotective and neurorestorative effects over a broad therapeutic time window, suggesting COA-Cl might be a novel and potent therapeutic agent for ischemic stroke.

  2. Radiofrequency attenuator and method

    DOEpatents

    Warner, Benjamin P.; McCleskey, T. Mark; Burrell, Anthony K.; Agrawal, Anoop; Hall, Simon B.

    2009-11-10

    Radiofrequency attenuator and method. The attenuator includes a pair of transparent windows. A chamber between the windows is filled with molten salt. Preferred molten salts include quarternary ammonium cations and fluorine-containing anions such as tetrafluoroborate (BF.sub.4.sup.-), hexafluorophosphate (PF.sub.6.sup.-), hexafluoroarsenate (AsF.sub.6.sup.-), trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3 C.sup.-). Radicals or radical cations may be added to or electrochemically generated in the molten salt to enhance the RF attenuation.

  3. Radiofrequency attenuator and method

    DOEpatents

    Warner, Benjamin P.; McCleskey, T. Mark; Burrell, Anthony K.; Agrawal, Anoop; Hall, Simon B.

    2009-01-20

    Radiofrequency attenuator and method. The attenuator includes a pair of transparent windows. A chamber between the windows is filled with molten salt. Preferred molten salts include quarternary ammonium cations and fluorine-containing anions such as tetrafluoroborate (BF.sub.4.sup.-), hexafluorophosphate (PF.sub.6.sup.-), hexafluoroarsenate (AsF.sub.6.sup.-), trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3C.sup.-). Radicals or radical cations may be added to or electrochemically generated in the molten salt to enhance the RF attenuation.

  4. Enhanced excitation-coupled calcium entry in myotubes expressing malignant hyperthermia mutation R163C is attenuated by dantrolene.

    PubMed

    Cherednichenko, Gennady; Ward, Chris W; Feng, Wei; Cabrales, Elaine; Michaelson, Luke; Samso, Montserrat; López, José R; Allen, Paul D; Pessah, Isaac N

    2008-04-01

    Dantrolene is the drug of choice for the treatment of malignant hyperthermia (MH) and is also useful for treatment of spasticity or muscle spasms associated with several clinical conditions. The current study examines the mechanisms of dantrolene's action on skeletal muscle and shows that one of dantrolene's mechanisms of action is to block excitation-coupled calcium entry (ECCE) in both adult mouse flexor digitorum brevis fibers and primary myotubes. A second important new finding is that myotubes isolated from mice heterozygous and homozygous for the ryanodine receptor type 1 R163C MH susceptibility mutation show significantly enhanced ECCE rates that could be restored to those measured in wild-type cells after exposure to clinical concentrations of dantrolene. We propose that this gain of ECCE function is an important etiological component of MH susceptibility and possibly contributes to the fulminant MH episode. The inhibitory potency of dantrolene on ECCE found in wild-type and MH-susceptible muscle is consistent with the drug's clinical potency for reversing the MH syndrome and is incomplete as predicted by its efficacy as a muscle relaxant.

  5. Resveratrol Co-Treatment Attenuates the Effects of HIV Protease Inhibitors on Rat Body Weight and Enhances Cardiac Mitochondrial Respiration

    PubMed Central

    Symington, Burger; Mapanga, Rudo F.; Norton, Gavin R.

    2017-01-01

    Since the early 1990s human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) emerged as a global health pandemic, with sub-Saharan Africa the hardest hit. While the successful roll-out of antiretroviral (ARV) therapy provided significant relief to HIV-positive individuals, such treatment can also elicit damaging side-effects. Here especially HIV protease inhibitors (PIs) are implicated in the onset of cardio-metabolic complications such as type-2 diabetes and coronary heart disease. As there is a paucity of data regarding suitable co-treatments within this context, this preclinical study investigated whether resveratrol (RSV), aspirin (ASP) or vitamin C (VitC) co-treatment is able to blunt side-effects in a rat model of chronic PI exposure (Lopinavir/Ritonavir treatment for 4 months). Body weights and weight gain, blood metabolite levels (total cholesterol, HDL, LDL, triglycerides), echocardiography and cardiac mitochondrial respiration were assessed in PI-treated rats ± various co-treatments. Our data reveal that PI treatment significantly lowered body weight and cardiac respiratory function while no significant changes were found for heart function and blood metabolite levels. Moreover, all co-treatments ameliorated the PI-induced decrease in body weight after 4 months of PI treatment, while RSV co-treatment enhanced cardiac mitochondrial respiratory capacity in PI-treated rats. This pilot study therefore provides novel hypotheses regarding RSV co-treatment that should be further assessed in greater detail. PMID:28107484

  6. Enhanced expression of Nrf2 in mice attenuates the fatty liver produced by a methionine- and choline-deficient diet

    SciTech Connect

    Zhang, Yu-Kun Jennifer; Yeager, Ronnie L.; Tanaka, Yuji; Klaassen, Curtis D.

    2010-06-15

    Oxidative stress has been proposed as an important promoter of the progression of fatty liver diseases. The current study investigates the potential functions of the Nrf2-Keap1 signaling pathway, an important hepatic oxidative stress sensor, in a rodent fatty liver model. Mice with no (Nrf2-null), normal (wild type, WT), and enhanced (Keap1 knockdown, K1-kd) expression of Nrf2 were fed a methionine- and choline-deficient (MCD) diet or a control diet for 5 days. Compared to WT mice, the MCD diet-caused hepatosteatosis was more severe in the Nrf2-null mice and less in the K1-kd mice. The Nrf2-null mice had lower hepatic glutathione and exhibited more lipid peroxidation, whereas the K1-kd mice had the highest amount of glutathione in the liver and developed the least lipid peroxidation among the three genotypes fed the MCD diet. The Nrf2 signaling pathway was activated by the MCD diet, and the Nrf2-targeted cytoprotective genes Nqo1 and Gst{alpha}1/2 were induced in WT and even more in K1-kd mice. In addition, Nrf2-null mice on both control and MCD diets exhibited altered expression profiles of fatty acid metabolism genes, indicating Nrf2 may influence lipid metabolism in liver. For example, mRNA levels of long chain fatty acid translocase CD36 and the endocrine hormone Fgf21 were higher in livers of Nrf2-null mice and lower in the K1-kd mice than WT mice fed the MCD diet. Taken together, these observations indicate that Nrf2 could decelerate the onset of fatty livers caused by the MCD diet by increasing hepatic antioxidant and detoxification capabilities.

  7. Gene-Category Analysis.

    PubMed

    Bauer, Sebastian

    2017-01-01

    Gene-category analysis is one important knowledge integration approach in biomedical sciences that combines knowledge bases such as Gene Ontology with lists of genes or their products, which are often the result of high-throughput experiments, gained from either wet-lab or synthetic experiments. In this chapter, we will motivate this class of analyses and describe an often used variant that is based on Fisher's exact test. We show that this approach has some problems in the context of Gene Ontology of which users should be aware. We then describe some more recent algorithms that try to address some of the shortcomings of the standard approach.

  8. THE SCENARIOS APPROACH TO ATTENUATION-BASED REMEDIES FOR INORGANIC AND RADIONUCLIDE CONTAMINANTS

    SciTech Connect

    Vangelas, K.; Rysz, M.; Truex, M.; Brady, P.; Newell, C.; Denham, M.

    2011-08-04

    Guidance materials based on use of conceptual model scenarios were developed to assist evaluation and implementation of attenuation-based remedies for groundwater and vadose zones contaminated with inorganic and radionuclide contaminants. The Scenarios approach is intended to complement the comprehensive information provided in the US EPA's Technical Protocol for Monitored Natural Attenuation (MNA) of Inorganic Contaminants by providing additional information on site conceptual models and extending the evaluation to consideration of Enhanced Attenuation approaches. The conceptual models incorporate the notion of reactive facies, defined as units with hydrogeochemical properties that are different from surrounding units and that react with contaminants in distinct ways. The conceptual models also incorporate consideration of biogeochemical gradients, defined as boundaries between different geochemical conditions that have been induced by waste disposal or other natural phenomena. Gradients can change over time when geochemical conditions from one area migrate into another, potentially affecting contaminant mobility. A recognition of gradients allows the attenuation-affecting conditions of a site to be projected into the future. The Scenarios approach provides a stepwise process to identify an appropriate category of conceptual model and refine it for a specific site. Scenario materials provide links to pertinent sections in the EPA technical protocol and present information about contaminant mobility and important controlling mechanism for attenuation-based remedies based on the categories of conceptual models.

  9. Cx3cr1 deficiency in mice attenuates hepatic granuloma formation during acute schistosomiasis by enhancing the M2-type polarization of macrophages.

    PubMed

    Ran, Lin; Yu, Qilin; Zhang, Shu; Xiong, Fei; Cheng, Jia; Yang, Ping; Xu, Jun-Fa; Nie, Hao; Zhong, Qin; Yang, Xueli; Yang, Fei; Gong, Quan; Kuczma, Michal; Kraj, Piotr; Gu, Weikuan; Ren, Bo-Xu; Wang, Cong-Yi

    2015-07-01

    Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1(-/-) mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO), an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis.

  10. Cx3cr1 deficiency in mice attenuates hepatic granuloma formation during acute schistosomiasis by enhancing the M2-type polarization of macrophages

    PubMed Central

    Ran, Lin; Yu, Qilin; Zhang, Shu; Xiong, Fei; Cheng, Jia; Yang, Ping; Xu, Jun-Fa; Nie, Hao; Zhong, Qin; Yang, Xueli; Yang, Fei; Gong, Quan; Kuczma, Michal; Kraj, Piotr; Gu, Weikuan; Ren, Bo-Xu; Wang, Cong-Yi

    2015-01-01

    ABSTRACT Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1−/− mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO), an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis. PMID:26035381

  11. Four Weeks of Supplementation With Isolated Soy Protein Attenuates Exercise-Induced Muscle Damage and Enhances Muscle Recovery in Well Trained Athletes: A Randomized Trial

    PubMed Central

    Shenoy, Shweta; Dhawan, Mrinal; Singh Sandhu, Jaspal

    2016-01-01

    Background The effects of consumption of isolated soy protein (ISP) for a chronic period (4 weeks) on exercise induced muscle damage (EIMD) in athletic population have never been explored. Objectives To examine the effects of ISP on muscle damage indices elicited via a bout of damaging exercise. Patients and Methods Forty males (20 boxers, 20 cyclists) aged 18 - 28 years were randomly assigned to two groups (ISP and Placebo) (n = 20). All participants who engaged themselves in specific, regular training of 30 hours a week during the competitive season were included in the study. Participants consumed the supplement and the placebo for 4 weeks. The damaging exercise consisted of 100 consecutive drop-jumps. Pre and post supplementation readings of the criterion variables, highly sensitive C reactive protein (hs-cRP), creatine Kinase (CK), myeloperoxidase (MPO), isometric muscle strength, maximum aerobic capacity (VO2 max), heart rate (HR) and muscle soreness were obtained at baseline (Day 1), at 24 hours (Day 2) and at 48 hours (Day 3) following EIMD. Results Differences were observed in pre and post supplementation values (P < 0.05) indicating the effectiveness of soy protein in attenuating muscle damage and enhancing muscle recovery. Conclusions Our findings suggest that soy protein; a vegetable based supplement is effective, in ameliorating the negative effects of EIMD in trained athletic population. PMID:27826398

  12. In Vitro Passage Selects for Chlamydia muridarum with Enhanced Infectivity in Cultured Cells but Attenuated Pathogenicity in Mouse Upper Genital Tract

    PubMed Central

    Chen, Chaoqun; Zhou, Zhou; Conrad, Turner; Yang, Zhangsheng; Dai, Jin; Li, Zhongyu

    2015-01-01

    Although modern Chlamydia muridarum has been passaged for decades, there are no reports on the consequences of serial passage with strong selection pressure on its fitness. In order to explore the potential for Pasteurian selection to induce genomic and phenotypic perturbations to C. muridarum, a starter population was passaged in cultured cells for 28 generations without standard infection assistance. The resultant population, designated CMG28, displays markedly reduced in vitro dependence on centrifugation for infection and low incidence and severity of upper genital tract pathology following intravaginal inoculation into mice compared to the parental C. muridarum population, CMG0. Deep sequencing of CMG0 and CMG28 revealed novel protein variants in the hypothetical genes TC0237 (Q117E) and TC0668 (G322R). In vitro attachment assays of isogenic plaque clone pairs with mutations in either TC0237 and TC0668 or only TC0237 reveal that TC0237(Q117E) is solely responsible for enhanced adherence to host cells. Paradoxically, double mutants, but not TC0237(Q117E) single mutants, display severely attenuated in vivo pathogenicity. These findings implicate TC0237 and TC0668 as novel genetic factors involved in chlamydial attachment and pathogenicity, respectively, and show that serial passage under selection pressure remains an effective tool for studying Chlamydia pathogenicity. PMID:25712926

  13. Attenuation by genistein of sodium-chloride-enhanced gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats.

    PubMed

    Tatsuta, M; Iishi, H; Baba, M; Yano, H; Uehara, H; Nakaizumi, A

    1999-01-29

    The effects of prolonged administration of genistein, a tyrosine-kinase inhibitor, on sodium-chloride-enhanced induction of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine, and the labeling and apoptotic indices and vessel counts in the gastric mucosa and gastric cancers, were investigated in Wistar rats. After 25 weeks of the carcinogen treatment, rats were fed chow pellets containing 10% sodium chloride and were given s.c. injections of genistein at dosages of 15 mg/kg or 30 mg/kg body weight every other day. In week 52, the incidence of gastric cancers was significantly greater in rats fed sodium chloride than in untreated control rats. Prolonged administration of genistein at a dosage of 30 mg/kg, but not 15 mg/kg, body weight significantly reduced the incidence of gastric cancers, which was increased by oral treatment with sodium chloride. Genistein at the higher dose significantly decreased the labeling index and vessel counts of the antral mucosa and the gastric cancers (which were increased by treatment with sodium chloride) and significantly increased the apoptotic index of the antral mucosa and the cancers (which was lowered by the treatment with sodium chloride). These findings suggest that genistein attenuates gastric carcinogenesis promoted by sodium chloride, by inducing increased apoptosis and lower cell proliferation and angiogenesis of antral mucosa and gastric cancers.

  14. Tonicity-responsive enhancer binding protein haplodeficiency attenuates seizure severity and NF-κB-mediated neuroinflammation in kainic acid-induced seizures

    PubMed Central

    Shin, H J; Kim, H; Heo, R W; Kim, H J; Choi, W S; Kwon, H M; Roh, G S

    2014-01-01

    Kainic acid (KA)-induced seizures followed by neuronal death are associated with neuroinflammation and blood–brain barrier (BBB) leakage. Tonicity-responsive enhancer binding protein (TonEBP) is known as a transcriptional factor activating osmoprotective genes, and in brain, it is expressed in neuronal nuclei. Thus dysregulation of TonEBP may be involved in the pathology of KA-induced seizures. Here we used TonEBP heterozygote (+/−) mice to study the roles of TonEBP. Electroencephalographic study showed that TonEBP (+/−) mice reduced seizure frequency and severity compared with wild type during KA-induced status epilepticus. Immunohistochemistry and western blotting analysis showed that KA-induced neuroinflammation and BBB leakage were dramatically reduced in TonEBP (+/−) mice. Similarly, TonEBP-specific siRNA reduced glutamate-induced death in HT22 hippocampal neuronal cells. TonEBP haplodeficiency prevented KA-induced nuclear translocation of NF-κB p65 and attenuated inflammation. Our findings identify TonEBP as a critical regulator of neuroinflammation and BBB leakage in KA-induced seizures, which suggests TonEBP as a good therapeutic target. PMID:24608792

  15. Dietary Prebiotics and Bioactive Milk Fractions Improve NREM Sleep, Enhance REM Sleep Rebound and Attenuate the Stress-Induced Decrease in Diurnal Temperature and Gut Microbial Alpha Diversity

    PubMed Central

    Thompson, Robert S.; Roller, Rachel; Mika, Agnieszka; Greenwood, Benjamin N.; Knight, Rob; Chichlowski, Maciej; Berg, Brian M.; Fleshner, Monika

    2017-01-01

    Severe, repeated or chronic stress produces negative health outcomes including disruptions of the sleep/wake cycle and gut microbial dysbiosis. Diets rich in prebiotics and glycoproteins impact the gut microbiota and may increase gut microbial species that reduce the impact of stress. This experiment tested the hypothesis that consumption of dietary prebiotics, lactoferrin (Lf) and milk fat globule membrane (MFGM) will reduce the negative physiological impacts of stress. Male F344 rats, postnatal day (PND) 24, received a diet with prebiotics, Lf and MFGM (test) or a calorically matched control diet. Fecal samples were collected on PND 35/70/91 for 16S rRNA sequencing to examine microbial composition and, in a subset of rats; Lactobacillus rhamnosus was measured using selective culture. On PND 59, biotelemetry devices were implanted to record sleep/wake electroencephalographic (EEG). Rats were exposed to an acute stressor (100, 1.5 mA, tail shocks) on PND 87 and recordings continued until PND 94. Test diet, compared to control diet, increased fecal Lactobacillus rhamnosus colony forming units (CFU), facilitated non-rapid eye movement (NREM) sleep consolidation (PND 71/72) and enhanced rapid eye movement (REM) sleep rebound after stressor exposure (PND 87). Rats fed control diet had stress-induced reductions in alpha diversity and diurnal amplitude of temperature, which were attenuated by the test diet (PND 91). Stepwise multiple regression analysis revealed a significant linear relationship between early-life Deferribacteres (PND 35) and longer NREM sleep episodes (PND 71/72). A diet containing prebiotics, Lf and MFGM enhanced sleep quality, which was related to changes in gut bacteria and modulated the impact of stress on sleep, diurnal rhythms and the gut microbiota. PMID:28119579

  16. Category Coherence and Category-Based Property Induction

    ERIC Educational Resources Information Center

    Rehder, Bob; Hastie, Reid

    2004-01-01

    One important property of human object categories is that they define the sets of exemplars to which newly observed properties are generalized. We manipulated the causal knowledge associated with novel categories and assessed the resulting strength of property inductions. We found that the theoretical coherence afforded to a category by…

  17. Jordan Algebraic Quantum Categories

    NASA Astrophysics Data System (ADS)

    Graydon, Matthew; Barnum, Howard; Ududec, Cozmin; Wilce, Alexander

    2015-03-01

    State cones in orthodox quantum theory over finite dimensional complex Hilbert spaces enjoy two particularly essential features: homogeneity and self-duality. Orthodox quantum theory is not, however, unique in that regard. Indeed, all finite dimensional formally real Jordan algebras -- arenas for generalized quantum theories with close algebraic kinship to the orthodox theory -- admit homogeneous self-dual positive cones. We construct categories wherein these theories are unified. The structure of composite systems is cast from universal tensor products of the universal C*-algebras enveloping ambient spaces for the constituent state cones. We develop, in particular, a notion of composition that preserves the local distinction of constituent systems in quaternionic quantum theory. More generally, we explicitly derive the structure of hybrid quantum composites with subsystems of arbitrary Jordan algebraic type.

  18. Beyond the Categories.

    PubMed

    Weeks, Jeffrey

    2015-07-01

    Shushu is a Turkish Cypriot drag performance artist and the article begins with a discussion of a short film about him by a Greek Cypriot playwright, film maker, and gay activist. The film is interesting in its own right as a documentary about a complex personality, but it is also relevant to wider discussion of sexual and gender identity and categorization in a country divided by history, religion, politics, and military occupation. Shushu rejects easy identification as gay or transgender, or anything else. He is his own self. But refusing a recognized and recognizable identity brings problems, and I detected a pervasive mood of melancholy in his portrayal. The article builds from this starting point to explore the problematic nature of identities and categorizations in the contemporary world. The analysis opens with the power of words and language in defining and classifying sexuality. The early sexologists set in motion a whole catalogue of categories which continue to shape sexual thinking, believing that they were providing a scientific basis for a more humane treatment of sexual variations. This logic continues in DSM-5. The historical effect, however, has been more complex. Categorizations have often fixed individuals into a narrow band of definitions and identities that marginalize and pathologize. The emergence of radical sexual-social movements from the late 1960s offered new forms of grassroots knowledge in opposition to the sexological tradition, but at first these movements worked to affirm rather than challenge the significance of identity categories. Increasingly, however, identities have been problematized and challenged for limiting sexual and gender possibilities, leading to the apparently paradoxical situation where sexual identities are seen as both necessary and impossible. There are emotional costs both in affirming a fixed identity and in rejecting one. Shushu is caught in this dilemma, leading to the pervasive sense of loss that shapes the

  19. Neuroprotective effect of novel cognitive enhancer noopept on AD-related cellular model involves the attenuation of apoptosis and tau hyperphosphorylation

    PubMed Central

    2014-01-01

    Background Noopept (N-phenyl-acetyl-L-prolylglycine ethyl ester) was constructed as a dipeptide analog of the standard cognition enhancer, piracetam. Our previous experiments have demonstrated the cognition restoring effect of noopept in several animal models of Alzheimer disease (AD). Noopept was also shown to prevent ionic disbalance, excitotoxicity, free radicals and pro-inflammatory cytokines accumulation, and neurotrophine deficit typical for different kinds of brain damages, including AD. In this study, we investigated the neuroprotective action of noopept on cellular model of AD, Aβ25–35-induced toxicity in PC12 cells and revealed the underlying mechanisms. Results The neuroprotective effect of noopept (added to the medium at 10 μM concentration, 72 hours before Аβ25–35) was studied on Аβ25–35-induced injury (5 μM for 24 h) in PC12 cells. The ability of drug to protect the impairments of cell viability, calcium homeostasis, ROS level, mitochondrial function, tau phosphorylation and neurite outgrowth caused by Аβ25–35 were evaluated. Following the exposure of PC12 cells to Аβ25–35 an increase of the level of ROS, intracellular calcium, and tau phosphorylation at Ser396 were observed; these changes were accompanied by a decrease in cell viability and an increase of apoptosis. Noopept treatment before the amyloid-beta exposure improved PC12 cells viability, reduced the number of early and late apoptotic cells, the levels of intracellular reactive oxygen species and calcium and enhanced the mitochondrial membrane potential. In addition, pretreatment of PC12 cell with noopept significantly attenuated tau hyperphosphorylation at Ser396 and ameliorated the alterations of neurite outgrowth evoked by Аβ25–35. Conclusions Taken together, these data provide evidence that novel cognitive enhancer noopept protects PC12 cell against deleterious actions of Aβ through inhibiting the oxidative damage and calcium overload as well as suppressing

  20. Conservation Level and Category Clustering

    ERIC Educational Resources Information Center

    Haynes, C. Rayfield; Kulhavy, Raymond W.

    1976-01-01

    Two experiments were conducted to test the hypothesis that category recall is related to the quantity conservation of mass, weight, and volume. The predicted association between conservation level and category recall was observed. (JMB)

  1. An overview on therapeutics attenuating amyloid β level in Alzheimer’s disease: targeting neurotransmission, inflammation, oxidative stress and enhanced cholesterol levels

    PubMed Central

    Zhou, Xiaoling; Li, Yifei; Shi, Xiaozhe; Ma, Chun

    2016-01-01

    Alzheimer’s disease (AD) is the most common underlying cause of dementia, and novel drugs for its treatment are needed. Of the different theories explaining the development and progression of AD, “amyloid hypothesis” is the most supported by experimental data. This hypothesis states that the cleavage of amyloid precursor protein (APP) leads to the formation of amyloid beta (Aβ) peptides that congregate with formation and deposition of Aβ plaques in the frontal cortex and hippocampus. Risk factors including neurotransmitter modulation, chronic inflammation, metal-induced oxidative stress and elevated cholesterol levels are key contributors to the disease progress. Current therapeutic strategies abating AD progression are primarily based on anti-acetylcholinesterase (AChE) inhibitors as cognitive enhancers. The AChE inhibitor, donepezil, is proven to strengthen cognitive functions and appears effective in treating moderate to severe AD patients. N-Methyl-D-aspartate receptor antagonist, memantine, is also useful, and its combination with donepezil demonstrated a strong stabilizing effect in clinical studies on AD. Nonsteroidal anti-inflammatory drugs delayed the onset and progression of AD and attenuated cognitive dysfunction. Based upon epidemiological evidence and animal studies, antioxidants emerged as potential AD preventive agents; however, clinical trials revealed inconsistencies. Pharmacokinetic and pharmacodynamic profiling demonstrated pleiotropic functions of the hypolipidemic class of drugs, statins, potentially contributing towards the prevention of AD. In addition, targeting the APP processing pathways, stimulating neuroprotective signaling mechanisms, using the amyloid anti-aggregants and Aβ immunotherapy surfaced as well-tested strategies in reducing the AD-like pathology. Overall, this review covers mechanism of inducing the Aβ formation, key risk factors and major therapeutics prevalent in the AD treatment nowadays. It also delineates the

  2. Putative Dopamine Agonist (KB220Z) Attenuates Lucid Nightmares in PTSD Patients: Role of Enhanced Brain Reward Functional Connectivity and Homeostasis Redeeming Joy

    PubMed Central

    McLaughlin, Thomas; Blum, Kenneth; Oscar-Berman, Marlene; Febo, Marcelo; Agan, Gozde; Fratantonio, James L.; Simpatico, Thomas; Gold, Mark S.

    2015-01-01

    Background Lucid dreams are frequently pleasant and training techniques have been developed to teach dreamers to induce them. In addition, the induction of lucid dreams has also been used as a way to ameliorate nightmares. On the other hand, lucid dreams may be associated with psychiatric conditions, including Post-Traumatic Stress Disorder (PTSD) and Reward Deficiency Syndrome-associated diagnoses. In the latter conditions, lucid dreams can assume an unpleasant and frequently terrifying character. Case Presentations We present two cases of dramatic alleviation of terrifying lucid dreams in patients with PTSD. In the first case study, a 51-year-old, obese woman, diagnosed with PTSD and depression, had attempted suicide and experienced terrifying lucid nightmares linked to sexual/physical abuse from early childhood by family members including her alcoholic father. Her vivid “bad dreams” remained refractory in spite of 6 months of treatment with Dialectical Behavioral Therapy (DBT) and standard pharmaceutical agents which included prazosin, clonidie and Adderall. The second 39-year-old PTSD woman patient had also suffered from lucid nightmares. Results The medication visit notes reveal changes in the frequency, intensity and nature of these dreams after the complex putative dopamine agonist KB220Z was added to the first patient’s regimen. The patient reported her first experience of an extended period of happy dreams. The second PTSD patient, who had suffered from lucid nightmares, was administered KB220Z to attenuate methadone withdrawal symptoms and incidentally reported dreams full of happiness and laughter. Conclusions These cases are discussed with reference to the known effects of KB220Z including enhanced dopamine homeostasis and functional connectivity of brain reward circuitry in rodents and humans. Their understanding awaits intensive investigation involving large-population, double-blinded studies. PMID:26132915

  3. NT-PGC-1α activation attenuates high-fat diet-induced obesity by enhancing brown fat thermogenesis and adipose tissue oxidative metabolism.

    PubMed

    Jun, Hee-Jin; Joshi, Yagini; Patil, Yuvraj; Noland, Robert C; Chang, Ji Suk

    2014-11-01

    The transcriptional coactivator peroxisome proliferator-activated receptor γ coactivator (PGC)-1α and its splice variant N terminal (NT)-PGC-1α regulate adaptive thermogenesis by transcriptional induction of thermogenic and mitochondrial genes involved in energy metabolism. We previously reported that full-length PGC-1α (FL-PGC-1α) is dispensable for cold-induced nonshivering thermogenesis in FL-PGC-1α(-/-) mice, since a slightly shorter but functionally equivalent form of NT-PGC-1α (NT-PGC-1α(254)) fully compensates for the loss of FL-PGC-1α in brown and white adipose tissue. In the current study, we challenged FL-PGC-1α(-/-) mice with a high-fat diet (HFD) to investigate the effects of diet-induced thermogenesis on HFD-induced obesity. Despite a large decrease in locomotor activity, FL-PGC-1α(-/-) mice exhibited the surprising ability to attenuate HFD-induced obesity. Reduced fat mass in FL-PGC-1α(-/-) mice was closely associated with an increase in body temperature, energy expenditure, and whole-body fatty acid oxidation (FAO). Mechanistically, FL-PGC-1α(-/-) brown adipose tissue had an increased capacity to oxidize fatty acids and dissipate energy as heat, in accordance with upregulation of thermogenic genes UCP1 and DIO2. Furthermore, augmented expression of FAO and lipolytic genes in FL-PGC-1α(-/-) white adipose tissue was highly correlated with decreased fat storage in adipose tissue. Collectively, our data highlight a protective effect of NT-PGC-1α on diet-induced obesity by enhancing diet-induced thermogenesis and FAO.

  4. Attenuation of diabetic retinopathy by enhanced inhibition of MMP-2 and MMP-9 using aspirin and minocycline in streptozotocin-diabetic rats.

    PubMed

    Bhatt, Lokesh Kumar; Addepalli, Veeranjaneyulu

    2010-02-12

    Interruptions of Matrix Metalloproteinase-2 (MMP-2) and Matrix Metalloproteinase-9 (MMP-9) have been shown to reduce the ensuing threatening risk factors of vascular complications of diabetes by alteration in Extracellular Matrix (ECM). We hypothesized that minocycline induced MMP-2 and MMP-9 inhibition can be enhanced by aspirin, a non-selective COX and tPA inhibitor and this combination can reduce progression of diabetic retinopathy. Diabetes was induced in male Wistar rats by streptozotocin (55 mg/kg i.p.). Four weeks after diabetes induction rats were treated with minocycline (50 mg/kg, p.o.) per se, aspirin (50 mg/kg, p.o.) per se, or minocycline in combination with aspirin for a period of four weeks. At the end of eighth week rats were anesthetized and electroretinograms were recorded. B-wave latency, B-wave amplitude and retinal permeability were measured. Histology was done and retinal thickness was measured. Zymography was carried out for MMP-2 and MMP-9 level determinations. B-wave amplitude was significantly decreased while B- wave latency was significantly increased in diabetic group when compared with normo-glycemic rats. Treatment with combination of minocycline and aspirin significantly reversed B-wave amplitude and latency compared with vehicle-treated diabetic controls. Blood retinal permeability and retinal thickness were also significantly attenuated by the treatment of minocycline in combination with aspirin. Results of the present study suggest that MMP-2 and MMP-9 inhibition in presence of COX inhibitor prevents the development of experimental diabetic retinopathy in rats and can be a potential approach for the treatment.

  5. INHIBITION OF PAN NEUROTROPHIN RECEPTOR P75 ATTENUATES DIESEL PARTICULATE-INDUCED ENHANCEMENT OF ALLERGIC AIRWAY RESPONSES IN C57/BL6J MICE

    EPA Science Inventory

    Recent investigations have linked neurotrophins including nerve growth factor (NGF), neurotrophin-3 (NT-3), and brain-derived neurotrophic factor (BDNF) to allergic airways diseases. Antibody blockade of NGF attenuates airway resistance in allergic mice. Diesel exhaust particle...

  6. Enhanced expression of HIV and SIV vaccine antigens in the structural gene region of live attenuated rubella viral vectors and their incorporation into virions.

    PubMed

    Virnik, Konstantin; Ni, Yisheng; Berkower, Ira

    2013-04-19

    Despite the urgent need for an HIV vaccine, its development has been hindered by virus variability, weak immunogenicity of conserved epitopes, and limited durability of the immune response. For other viruses, difficulties with immunogenicity were overcome by developing live attenuated vaccine strains. However, there is no reliable method of attenuation for HIV, and an attenuated strain would risk reversion to wild type. We have developed rubella viral vectors, based on the live attenuated vaccine strain RA27/3, which are capable of expressing important HIV and SIV vaccine antigens. The rubella vaccine strain has demonstrated safety, immunogenicity, and long lasting protection in millions of children. Rubella vectors combine the growth and immunogenicity of live rubella vaccine with the antigenicity of HIV or SIV inserts. This is the first report showing that live attenuated rubella vectors can stably express HIV and SIV vaccine antigens at an insertion site located within the structural gene region. Unlike the Not I site described previously, the new site accommodates a broader range of vaccine antigens without interfering with essential viral functions. In addition, antigens expressed at the structural site were controlled by the strong subgenomic promoter, resulting in higher levels and longer duration of antigen expression. The inserts were expressed as part of the structural polyprotein, processed to free antigen, and incorporated into rubella virions. The rubella vaccine strain readily infects rhesus macaques, and these animals will be the model of choice for testing vector growth in vivo and immunogenicity.

  7. 40 CFR 98.440 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... geologic formations. (b) This source category includes all wells permitted as Class VI under the Underground Injection Control program. (c) This source category does not include a well or group of wells where a CO2 stream is being injected in subsurface geologic formations to enhance the recovery of oil...

  8. 40 CFR 98.440 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... geologic formations. (b) This source category includes all wells permitted as Class VI under the Underground Injection Control program. (c) This source category does not include a well or group of wells where a CO2 stream is being injected in subsurface geologic formations to enhance the recovery of oil...

  9. Consumption of dairy yogurt with the polysaccharide rhamnogalacturonan from the peel of the Korean citrus hallabong enhances immune function and attenuates the inflammatory response.

    PubMed

    Lee, Mi-Hyang; Kim, Minjoo; Kim, Minkyung; Kwak, Jung Hyun; Chang, Dong Hoon; Yu, Won Kyu; Lee, Sang-Hyun; Lee, Jong Ho

    2016-06-15

    The aim of this study was to investigate the impact of consuming dairy yogurt supplemented with rhamnogalacturonan (RG), a polysaccharide from the peel of the Korean citrus hallabong, on natural killer (NK) cell activity and circulating cytokine levels. A randomized, double-blind, placebo-controlled study was conducted on 120 nondiabetic and nonobese subjects. Over an eight-week period, the test group consumed one pack (150 mL) of dairy yogurt containing 50 mg of probiotics and 100 mg of hallabong peel polysaccharide (60% RG) each day, whereas the placebo group consumed the same product without the hallabong peel supplement. NK cell activity (%) was measured based on the ratios of the effector cells (E; peripheral blood mononuclear cells, PBMCs) from each participant relative to the target cells (T; K562 cells) at E : T ratios of 10 : 1, 5 : 1, 2.5 : 1, or 1.25 : 1. NK cell activities under all assay conditions and interleukin (IL)-12 and interferon (IFN)-γ levels were significantly increased in the test group at eight weeks compared to the baseline values, whereas the placebo group showed a significant increase only in NK cell activity at E : T = 1.25 : 1. The test group had significantly greater increases in the changes in serum NK cell activity at the E : T ratios of 10 : 1, 5 : 1, and 2.5 : 1 and in the increases in IL-12 and IFN-γ levels than were observed in the placebo group, after adjusting for baseline values. After eight weeks of treatment, significant reductions were found in IL-6 and IL-1β levels in both the placebo and test groups. The daily consumption of dairy yogurt supplemented with RG, a polysaccharide from the peel of the Korean citrus hallabong, enhanced NK cell function and attenuated pro-inflammatory cytokine levels (ClinicalTrials.gov: NCT02535663).

  10. Cholesterol reduction by methyl-β-cyclodextrin attenuates the delta opioid receptor-mediated signaling in neuronal cells but enhances it in non-neuronal cells

    PubMed Central

    Huang, Peng; Xu, Wei; Yoon, Su-In; Chen, Chongguang; Chong, Parkson Lee-Gau; Liu-Chen, Lee-Yuan

    2008-01-01

    Opioid receptors have been shown to be located in and regulated by lipid rafts/caveolae in caveolin-rich non-neuronal cells. Here, we found that caveolin-1 level was very low in rat brain and undetectable in NG108-15 cells, which endogenously express delta opioid receptors (DOR). Rat caudate putamen (CPu) membranes, NG108-15 cells and CHO cells stably transfected with FLAG-mouse-DOR (CHO-FLAG-mDOR) were homogenized, sonicated in a detergent-free 0.5 M Na2CO3 buffer and fractionated through discontinuous or continuous sucrose density gradients. About 70% of opioid receptors in CPu and DOR in both cell lines were present in low-density (5-20% sucrose) membrane-domains enriched in cholesterol and ganglioside M1 (GM1), characteristics of lipid rafts in plasma membranes. In both cells, stimulation with permeable or non-permeable full agonists, but not with partial or inverse agonists, for 30 min shifted ∼25% of DORs out of rafts, by a naloxone-reversible and pertussis toxin-insensitive mechanism, which may undergo internalization. Methyl-β-cyclodextrin (MCD) treatment greatly reduced cholesterol and shifted DOR to higher-density fractions and decreased DPDPE affinities. MCD treatment attenuated DPDPE-induced [35S]GTPγS binding in CPu and NG108-15 cells, but enhanced it in CHO-FLAG-mDOR cells. In CHO-FLAG-mDOR cells, Gαi co-immunoprecipitated with caveolin-1, which was shown to inhibit Gαi/o, and MCD treatment dramatically reduced the association leading to disinhibition. Thus, although localization in rafts and agonist-induced shift of DOR are independent of caveolin-1, lipid rafts sustain DOR-mediated signaling in caveolin-deficient neuronal cells, but appear to inhibit it in caveolin-enriched non-neuronal cells. Cholesterol-dependent association of caveolin-1 with and the resulting inhibition of G proteins may be a contributing factor. PMID:17141202

  11. Category vs. Object Knowledge in Category-Based Induction

    ERIC Educational Resources Information Center

    Murphy, Gregory L.; Ross, Brian H.

    2010-01-01

    In one form of category-based induction, people make predictions about unknown properties of objects. There is a tension between predictions made based on the object's specific features (e.g., objects above a certain size tend not to fly) and those made by reference to category-level knowledge (e.g., birds fly). Seven experiments with artificial…

  12. Category vs. Object Knowledge in Category-based Induction

    PubMed Central

    Murphy, Gregory L.; Ross, Brian H.

    2009-01-01

    In one form of category-based induction, people make predictions about unknown properties of objects. There is a tension between predictions made based on the object’s specific features (e.g., objects above a certain size tend not to fly) and those made by reference to category-level knowledge (e.g., birds fly). Seven experiments with artificial categories investigated these two sources of induction by looking at whether people used information about correlated features within categories, suggesting that they focused on feature-feature relations rather than summary categorical information. The results showed that people relied heavily on such correlations, even when there was no reason to think that the correlations exist in the population. The results suggested that people’s use of this strategy is largely unreflective, rather than strategically chosen. These findings have important implications for models of category-based induction, which generally ignore feature-feature relations. PMID:20526447

  13. The way to a man's heart is through his stomach: much 'diaphragmatic' attenuation is likely gastric, and effervescent granules enhance cardiac imaging.

    PubMed

    Munn, Samson

    2004-12-01

    Avoidance of falsely positive results depends on distinguishing reality from artifact, in turn depending on images of highest quality. In radionuclide cardiac imaging, an inferior wall artifactual defect, so called "diaphragmatic attenuation", is particularly common and vexing. Despite the historically held view, analysis and review of the literature suggest the defect is likely not diaphragmatic but rather primarily due to attenuation by nearby stomach wall. The explanation is based on gravity and anatomy. With this improved understanding, effervescent granules were given as a clinical, nonresearch measure to nine patients during myocardial scanning. It was observed that two-thirds demonstrated moderate or marked lessening of attenuation. An additional benefit is lessening of artifact by extracardiac activity. These benefits may also apply to other sorts of cardiac radionuclide imaging. The significance of this new imaging method is discussed and various avenues of research are proposed.

  14. The Coordination of Unlike Categories.

    ERIC Educational Resources Information Center

    Bayer, Samuel

    1996-01-01

    Argues that the account of coordination of unlike categories ought to be unified with the account of feature neutralization under phonological identity. Further argues that this unified account ought not be couched in terms of string of features, but rather in terms of the logic of categories. Study concludes with a discussion of the interactions…

  15. Co-administration of attenuated Mycoplasma hyopneumoniae 168 strain with bacterial DNA enhances the local and systemic immune response after intranasal vaccination in pigs.

    PubMed

    Li, Yunfeng; Li, Pengcheng; Wang, Xueping; Yu, Qinghua; Yang, Qian

    2012-03-09

    Mycoplasma hyopneumoniae, the primary pathogen of enzootic pneumonia, occurs worldwide and causes major economic losses to the pig industry. M. hyopneumoniae infects pigs at mucosal surfaces of respiratory tract. The aim of the present study was to investigate if the protection rate against M. hyopneumoniae infection following intranasal immunization with attenuated M. hyopneumoniae 168 strain is improved by administration of bacterial DNA containing CpG motifs. Thirty pigs were immunized intranasally or intramuscularly and the levels of local respiratory tract and systemic immune responses were detected. The results showed that the number of intraepithelial lymphocytes in the tracheal fork, the levels of cytokine IL-6, and M. hyopneumoniae specific SIgA in local nasal cavity increased respectively after intranasal vaccination with the attenuated M. hyopneumoniae 168 strain alone. However, the levels of IL-10 and IFN-γ in local nasal cavity, the number of intraepithelial lymphocytes in trachea, CD4(+) and CD8(+) T lymphocytes in the lung and hilar lymph nodes, the specific IgG antibody level in serum on 35 day post immunization were all increased significantly after intranasal vaccination of the attenuated M. hyopneumoniae 168 strain adjuvanted with bacterial DNA. We concluded that intranasal administration of attenuated M. hyopneumoniae 168 strain adjuvanted with bacterial DNA may be effective in evoking the local cellular and humoral immune response in the respiratory tract and the systemic immune response. Intranasal vaccination will be effective in prevention of the transmission and prevalence of MPS.

  16. Natural attenuation software (NAS): Assessing remedial strategies and estimating timeframes

    USGS Publications Warehouse

    Mendez, E.; Widdowson, M.; Chapelle, F.; Casey, C.

    2005-01-01

    Natural Attenuation Software (NAS) is a screening tool to estimate remediation timeframes for monitored natural attenuation (MNA) and to assist in decision-making on the level of source zone treatment in conjunction with MNA using site-specific remediation objectives. Natural attenuation processes that NAS models include are advection, dispersion, sorption, non-aqueous phase liquid (NAPL) dissolution, and biodegradation of either petroleum hydrocarbons or chlorinated ethylenes. Newly-implemented enhancements to NAS designed to maximize the utility of NAS for site managers were observed. NAS has expanded source contaminant specification options to include chlorinated ethanes and chlorinated methanes, and to allow for the analysis of any other user-defined contaminants that may be subject to microbially-mediated transformations (heavy metals, radioisotopes, etc.). Included is the capability to model co-mingled plumes, with constituents from multiple contaminant categories. To enable comparison of remediation timeframe estimates between MNA and specific engineered remedial actions , NAS was modified to incorporate an estimation technique for timeframes associated with pump-and-treat remediation technology for comparison to MNA. This is an abstract of a paper presented at the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

  17. Enhancing the quality of radiographic images acquired with point-like gamma-ray sources through correction of the beam divergence and attenuation

    NASA Astrophysics Data System (ADS)

    Silvani, M. I.; Almeida, G. L.; Lopes, R. T.

    2014-11-01

    Radiographic images acquired with point-like gamma-ray sources exhibit a desirable low penumbra effects specially when positioned far away from the set object-detector. Such an arrangement frequently is not affordable due to the limited flux provided by a distant source. A closer source, however, has two main drawbacks, namely the degradation of the spatial resolution - as actual sources are only approximately punctual - and the non-homogeneity of the beam hitting the detector, which creates a false attenuation map of the object being inspected. This non-homogeneity is caused by the beam divergence itself and by the different thicknesses traversed the beam even if the object were an homogeneous flat plate. In this work, radiographic images of objects with different geometries, such as flat plates and pipes have undergone a correction of beam divergence and attenuation addressing the experimental verification of the capability and soundness of an algorithm formerly developed to generate and process synthetic images. The impact of other parameters, including source-detector gap, attenuation coefficient, ratio defective-to-main hull thickness and counting statistics have been assessed for specifically tailored test-objects aiming at the evaluation of the ability of the proposed method to deal with different boundary conditions. All experiments have been carried out with an X-ray sensitive Imaging Plate and reactor-produced 198Au and 165Dy sources. The results have been compared with other technique showing a better capability to correct the attenuation map of inspected objects unveiling their inner structure otherwise concealed by the poor contrast caused by the beam divergence and attenuation, in particular for those regions far apart from the vertical of the source.

  18. Enhancing the quality of radiographic images acquired with point-like gamma-ray sources through correction of the beam divergence and attenuation

    SciTech Connect

    Silvani, M. I.; Almeida, G. L.; Lopes, R. T.

    2014-11-11

    Radiographic images acquired with point-like gamma-ray sources exhibit a desirable low penumbra effects specially when positioned far away from the set object-detector. Such an arrangement frequently is not affordable due to the limited flux provided by a distant source. A closer source, however, has two main drawbacks, namely the degradation of the spatial resolution - as actual sources are only approximately punctual - and the non-homogeneity of the beam hitting the detector, which creates a false attenuation map of the object being inspected. This non-homogeneity is caused by the beam divergence itself and by the different thicknesses traversed the beam even if the object were an homogeneous flat plate. In this work, radiographic images of objects with different geometries, such as flat plates and pipes have undergone a correction of beam divergence and attenuation addressing the experimental verification of the capability and soundness of an algorithm formerly developed to generate and process synthetic images. The impact of other parameters, including source-detector gap, attenuation coefficient, ratio defective-to-main hull thickness and counting statistics have been assessed for specifically tailored test-objects aiming at the evaluation of the ability of the proposed method to deal with different boundary conditions. All experiments have been carried out with an X-ray sensitive Imaging Plate and reactor-produced {sup 198}Au and {sup 165}Dy sources. The results have been compared with other technique showing a better capability to correct the attenuation map of inspected objects unveiling their inner structure otherwise concealed by the poor contrast caused by the beam divergence and attenuation, in particular for those regions far apart from the vertical of the source.

  19. Biased allocation of faces to social categories.

    PubMed

    Dotsch, Ron; Wigboldus, Daniël H J; van Knippenberg, Ad

    2011-06-01

    Three studies show that social categorization is biased at the level of category allocation. In all studies, participants categorized faces. In Studies 1 and 2, participants overallocated faces with criminal features--a stereotypical negative trait--to the stigmatized Moroccan category, especially if they were prejudiced. On the contrary, the stereotype-irrelevant negative trait stupid did not lead to overallocation to the Moroccan category. In Study 3, using the stigmatized category homosexual, the previously used negative trait criminal--irrelevant to the homosexual stereotype--did not lead to overallocation, but the stereotype-relevant positive trait femininity did. These results demonstrate that normative fit is higher for faces with stereotype-relevant features regardless of valence. Moreover, individual differences in implicit prejudice predicted the extent to which stereotype-relevant traits elicited overallocation: Whereas more negatively prejudiced people showed greater overallocation of faces associated with negative stereotype-relevant traits, they showed less overallocation of faces associated with positive stereotype-relevant traits. These results support our normative fit hypothesis: In general, normative fit is better for faces with stereotypical features. Moreover, normative fit is enhanced for prejudiced individuals when these features are evaluatively congruent. Social categorization thus may be biased in itself.

  20. Psychopathic disorder: a category mistake?

    PubMed Central

    Holmes, C A

    1991-01-01

    Although the concept of psychopathy retains its currency in British psychiatry, apparently being meaningful as well as useful to practitioners (1), it is often taken to refer to a purely legal category with social control functions rather than a medical diagnosis with treatment implications. I wish, in this brief article, to suggest that it is essentially, and most usefully, an ethical category which stands outside the diagnostic framework of present-day psychiatry. PMID:1870086

  1. Data categories for marine planning

    USGS Publications Warehouse

    Lightsom, Frances L.; Cicchetti, Giancarlo; Wahle, Charles M.

    2015-01-01

    The U.S. National Ocean Policy calls for a science- and ecosystem-based approach to comprehensive planning and management of human activities and their impacts on America’s oceans. The Ocean Community in Data.gov is an outcome of 2010–2011 work by an interagency working group charged with designing a national information management system to support ocean planning. Within the working group, a smaller team developed a list of the data categories specifically relevant to marine planning. This set of categories is an important consensus statement of the breadth of information types required for ocean planning from a national, multidisciplinary perspective. Although the categories were described in a working document in 2011, they have not yet been fully implemented explicitly in online services or geospatial metadata, in part because authoritative definitions were not created formally. This document describes the purpose of the data categories, provides definitions, and identifies relations among the categories and between the categories and external standards. It is intended to be used by ocean data providers, managers, and users in order to provide a transparent and consistent framework for organizing and describing complex information about marine ecosystems and their connections to humans.

  2. DC attenuation meter

    DOEpatents

    Hargrove, Douglas L.

    2004-09-14

    A portable, hand-held meter used to measure direct current (DC) attenuation in low impedance electrical signal cables and signal attenuators. A DC voltage is applied to the signal input of the cable and feedback to the control circuit through the signal cable and attenuators. The control circuit adjusts the applied voltage to the cable until the feedback voltage equals the reference voltage. The "units" of applied voltage required at the cable input is the system attenuation value of the cable and attenuators, which makes this meter unique. The meter may be used to calibrate data signal cables, attenuators, and cable-attenuator assemblies.

  3. Polyphenolic Extract of Euphorbia supina Attenuates Manganese-Induced Neurotoxicity by Enhancing Antioxidant Activity through Regulation of ER Stress and ER Stress-Mediated Apoptosis

    PubMed Central

    Bahar, Entaz; Lee, Geum-Hwa; Bhattarai, Kashi Raj; Lee, Hwa-Young; Choi, Min-Kyung; Rashid, Harun-Or; Kim, Ji-Ye; Chae, Han-Jung; Yoon, Hyonok

    2017-01-01

    Manganese (Mn) is an important trace element present in human body, which acts as an enzyme co-factor or activator in various metabolic reactions. While essential in trace amounts, excess levels of Mn in human brain can produce neurotoxicity, including idiopathic Parkinson’s disease (PD)-like extrapyramidal manganism symptoms. This study aimed to investigate the protective role of polyphenolic extract of Euphorbia supina (PPEES) on Mn-induced neurotoxicity and the underlying mechanism in human neuroblastoma SKNMC cells and Sprague-Dawley (SD) male rat brain. PPEES possessed significant amount of total phenolic and flavonoid contents. PPEES also showed significant antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and reducing power capacity (RPC) assays. Our results showed that Mn treatment significantly reduced cell viability and increased lactate dehydrogenase (LDH) level, which was attenuated by PPEES pretreatment at 100 and 200 µg/mL. Additionally, PPEES pretreatment markedly attenuated Mn-induced antioxidant status alteration by resolving the ROS, MDA and GSH levels and SOD and CAT activities. PPEES pretreatment also significantly attenuated Mn-induced mitochondrial membrane potential (ΔΨm) and apoptosis. Meanwhile, PPEES pretreatment significantly reversed the Mn-induced alteration in the GRP78, GADD34, XBP-1, CHOP, Bcl-2, Bax and caspase-3 activities. Furthermore, administration of PPEES (100 and 200 mg/kg) to Mn exposed rats showed improvement of histopathological alteration in comparison to Mn-treated rats. Moreover, administration of PPEES to Mn exposed rats showed significant reduction of 8-OHdG and Bax immunoreactivity. The results suggest that PPEES treatment reduces Mn-induced oxidative stress and neuronal cell loss in SKNMC cells and in the rat brain. Therefore, PPEES may be considered as potential treat-ment in Mn-intoxicated patients. PMID:28146110

  4. Regulated delayed expression of rfc enhances the immunogenicity and protective efficacy of a heterologous antigen delivered by live attenuated Salmonella enterica vaccines.

    PubMed

    Kong, Qingke; Liu, Qing; Jansen, Angela M; Curtiss, Roy

    2010-08-23

    The Salmonella rfc gene encodes the O-antigen polymerase. We constructed three strains in which we replaced the native rfc promoter with the arabinose-dependent araC P(BAD) promoter so that rfc expression was dependent on exogenously supplied arabinose provided during in vitro growth. The three mutant strains were designed to synthesize different amounts of Rfc by altering the ribosome-binding sequence and start codon. We examined these strains for a number of in vitro characteristics compared to an isogenic Deltarfc mutant and the wild-type parent strain. One promoter-replacement mutation, DeltaP(rfc174), yielded an optimal profile, exhibiting wild-type characteristics when grown with arabinose, and Deltarfc characteristics when grown without arabinose. In addition, when administered orally, the DeltaP(rfc174) strain was completely attenuated in for virulence in mice. The DeltaP(rfc174) mutation was introduced into attenuated Salmonella vaccine strain chi9241 (DeltapabA DeltapabB DeltaasdA) followed by introduction of an Asd(+) balanced-lethal plasmid to designed for expression of the pneumococcal surface protein PspA. Mice immunized with either chi9241 or its DeltaP(rfc174) derivative expressing pspA were protected against S. pneumoniae challenge.

  5. Prognosis of Hurricanes CATEGORIE-5

    NASA Astrophysics Data System (ADS)

    Perez-Peraza, Jorge; Velasco Herrera, Victor Manuel; Zapotitla Roman, Julian; Juarez Zuñiga, Alan

    Category-5 Hurricanes are the most devastating from the standpoint of human and economic losses. Approximately 80 cyclones per year occurring worldwide, from which 8.8 per year occur on average in different regions of the Atlantic. However, category-5 Hurricanes do not follow a cyclic pattern but ar rather of quasi-stochastic nature. To assist in the alert processes o of hurricanes, we propose here a method to predict those kinds of hurricanes based on the Wavelet Analysis and applying techniques of Fuzzy Logic. For our study we consider North Atlantic category-5 hurricanes since 1920. Data was transformed into a series of Pulses with unitary value at the dates of hurricanes occurrence and 0 for dates of no occurrence. By means of the Wavelet transform we determine dominant oscillation periods. Under the hypothesis that the occurrence of hurricanes of this category can be described by the certain periodicities, we can define the dominant periods of oscillation and establish correspondence rules using fuzzy logic. The fuzzy logic searches for associations between the hurricanes occurrence and the behavior of the harmonics, and then delimits the occurrence of the next hurricane. The Wavelet Power Spectrum yields the following periodicities 2, 9, 14 and 24 years. According to the behavior of the harmonics we found that their combination restricts regions of possible Hurricane occurrence. Interpolation of this sinusoidal behavior allows for a good reconstruction of past Hurricanes dates as well as extrapolation to the future. In this way we conclude that there is a good probability that the next category-5 Hurricane in the north Atlantic occur of 2014-2015. Regarding categorie-5 typhoons in the pacific we delimitate the genesis regions of western of these kind of typhoons.

  6. Mosquito and Blackfly Category Manual.

    ERIC Educational Resources Information Center

    Bowman, James S.; And Others

    This manual provides information needed to meet the standards for pesticide applicator certification. Section one is concerned with the morphology, life cycle and breeding areas of mosquitoes and the diseases resulting from their presence. The second section covers similar categories in relation to the black fly population. Calculation methods and…

  7. Sentence Processing with Empty Categories.

    ERIC Educational Resources Information Center

    Gibson, Edward; Hickok, Gregory

    1993-01-01

    Pickering and Barry's recent argument against the existence of empty categories (ECs) in human sentence processing is disputed. It is argued here that ECs may still play a linking role between thematic role assigners and wh-phrases. One possible parsing algorithm is given that accounts for Pickering and Barry's data. (28 references) (Author/LB)

  8. Hurricane Irene at Category 3

    NASA Video Gallery

    Video sequence taken by the crew of the ISS on Aug. 23, 2011 at approximately 2:15PM EST. At that time, Hurricane Irene was a Category 3 storm with peak winds estimated at 115mph, moving west-north...

  9. Linguistic Markedness and Category Learning

    ERIC Educational Resources Information Center

    Haskell, Todd R.; Mansfield, Cade D.; Brewer, Katherine M.

    2011-01-01

    Several psycholinguistic theories have appealed to the linguistic notion of markedness to help explain asymmetrical patterns of behavioural data. We suggest that this sort of markedness is best thought of as a derived rather than a primitive notion, emerging when the distributional properties of linguistic categories interact with general-purpose…

  10. Learnable Classes of Categorial Grammars.

    ERIC Educational Resources Information Center

    Kanazawa, Makoto

    Learnability theory is an attempt to illuminate the concept of learnability using a mathematical model of learning. Two models of learning of categorial grammars are examined here: the standard model, in which sentences presented to the learner are flat strings of words, and one in which sentences are presented in the form of functor-argument…

  11. Causal Categories: Relativistically Interacting Processes

    NASA Astrophysics Data System (ADS)

    Coecke, Bob; Lal, Raymond

    2013-04-01

    A symmetric monoidal category naturally arises as the mathematical structure that organizes physical systems, processes, and composition thereof, both sequentially and in parallel. This structure admits a purely graphical calculus. This paper is concerned with the encoding of a fixed causal structure within a symmetric monoidal category: causal dependencies will correspond to topological connectedness in the graphical language. We show that correlations, either classical or quantum, force terminality of the tensor unit. We also show that well-definedness of the concept of a global state forces the monoidal product to be only partially defined, which in turn results in a relativistic covariance theorem. Except for these assumptions, at no stage do we assume anything more than purely compositional symmetric-monoidal categorical structure. We cast these two structural results in terms of a mathematical entity, which we call a causal category. We provide methods of constructing causal categories, and we study the consequences of these methods for the general framework of categorical quantum mechanics.

  12. Melatonin treatment attenuates postharvest decay and maintains nutritional quality of strawberry fruits (Fragaria×anannasa cv. Selva) by enhancing GABA shunt activity.

    PubMed

    Aghdam, Morteza Soleimani; Fard, Javad Rezapour

    2017-04-15

    Fresh strawberry fruits as perishable commodities have a short postharvest life and are prone to postharvest fungal decay. In this study, the impact of 0, 1, 10, 100 and 1000μmol/L melatonin on attenuating fungal decay and maintaining nutritional quality of strawberry fruits was investigated during storage at 4°C for 12days. Melatonin treatment at 100μmol/L triggered H2O2 accumulation, which result from higher superoxide dismutase (SOD) activity, associated with lower catalase (CAT) and ascorbate peroxidase (APX) activities, leading to fruits with lower decay. Higher H2O2 accumulation was concurrent with higher phenylalanine ammonia lyase (PAL) enzyme activity leading to higher total phenols and anthocyanins accumulation along with higher DPPH scavenging capacity. Also, strawberry fruits treated with melatonin exhibited higher γ-aminobutyric acid transaminase (GABA-T) enzyme activity which ensured sufficient ATP supplying leading to higher unsaturated/saturated fatty acids (unSFA/SFA) ratio.

  13. Rosmarinic Acid Attenuates Cell Damage against UVB Radiation-Induced Oxidative Stress via Enhancing Antioxidant Effects in Human HaCaT Cells

    PubMed Central

    Fernando, Pattage Madushan Dilhara Jayatissa; Piao, Mei Jing; Kang, Kyoung Ah; Ryu, Yea Seong; Hewage, Susara Ruwan Kumara Madduma; Chae, Sung Wook; Hyun, Jin Won

    2016-01-01

    This study was designed to investigate the cytoprotective effect of rosmarinic acid (RA) on ultraviolet B (UVB)-induced oxidative stress in HaCaT keratinocytes. RA exerted a significant cytoprotective effect by scavenging intracellular ROS induced by UVB. RA also attenuated UVB-induced oxidative macromolecular damage, including protein carbonyl content, DNA strand breaks, and the level of 8-isoprostane. Furthermore, RA increased the expression and activity of superoxide dismutase, catalase, heme oxygenase-1, and their transcription factor Nrf2, which are decreased by UVB radiation. Collectively, these data indicate that RA can provide substantial cytoprotection against the adverse effects of UVB radiation by modulating cellular antioxidant systems, and has potential to be developed as a medical agent for ROS-induced skin diseases. PMID:26759705

  14. Attenuation of mirror image and enhancement of the signal-to-noise ratio in a Talbot bands optical coherence tomography system.

    PubMed

    Bradu, Adrian; Podoleanu, Adrian Gh

    2011-07-01

    A Fourier domain optical coherence tomography setup is presented built around an optical configuration that exhibits Talbot bands. A low astigmatism spectrometer is used, employing a spherical mirror and a cylindrical lens between a diffraction grating and a linear CCD camera. To produce Talbot bands, the two interferometer beams--object and reference--are laterally shifted in respect to each other in their way toward the diffraction grating. This allows attenuation of mirror terms and optimization of the sensitivity profile. We evaluate the optimization of the sensitivity profile with depth, in respect to its overall strength and its position peak, which can be shifted toward a larger optical path difference in the interferometer. We demonstrate the efficiency of such a configuration at large depths by imaging a thick phantom and human skin in vivo for different values of the lateral distance between the two beams.

  15. Pressure surge attenuator

    DOEpatents

    Christie, Alan M.; Snyder, Kurt I.

    1985-01-01

    A pressure surge attenuation system for pipes having a fluted region opposite crushable metal foam. As adapted for nuclear reactor vessels and heads, crushable metal foam is disposed to attenuate pressure surges.

  16. Global Attenuation Model of the Upper Mantle

    NASA Astrophysics Data System (ADS)

    Adenis, A.; Debayle, E.; Ricard, Y. R.

    2015-12-01

    We present a three-dimensional shear attenuation model based on a massive surface wave data-set (372,629 Rayleigh waveforms analysed in the period range 50-300s by Debayle and Ricard, 2012). For each seismogram, this approach yields depth-dependent path average models of shear velocity and quality factor, and a set of fundamental and higher-mode dispersion and attenuation curves. We combine these attenuation measurements in a tomographic inversion after a careful rejection of the noisy data. We first remove data likely to be biased by a poor knowledge of the source. Then we assume that waves corresponding to events having close epicenters and recorded at the same station sample the same elastic and anelastic structure, we cluster the corresponding rays and average the attenuation measurements. Logarithms of the attenuations are regionalized using the non-linear east square formalism of Tarantola and Valette (1982), resulting in attenuation tomographic maps between 50s and 300s. After a first inversion, outlyers are rejected and a second inversion yields a moderate variance reduction of about 20%. We correct the attenuation curves for focusing effect using the linearized ray theory of Woodhouse and Wong (1986). Accounting for focussing effects allows building tomographic maps with variance reductions reaching 40%. In the period range 120-200s, the root mean square of the model perturbations increases from about 5% to 20%. Our 3-D attenuation models present strong agreement with surface tectonics at period lower than 200s. Areas of low attenuation are located under continents and areas of high attenuation are associated with oceans. Surprisingly, although mid oceanic ridges are located in attenuating regions, their signature, even if enhanced by focusing corrections, remains weaker than in the shear velocity models. Synthetic tests suggests that regularisation contributes to damp the attenuation signature of ridges, which could therefore be underestimated.

  17. Blockage of Autophagy in C6 Glioma Cells Enhanced Radiosensitivity Possibly by Attenuating DNA-PK-Dependent DSB Due to Limited Ku Nuclear Translocation and DNA Binding.

    PubMed

    Liu, C; He, W; Jin, M; Li, H; Xu, H; Liu, H; Yang, K; Zhang, T; Wu, G; Ren, J

    2015-01-01

    Glioblastoma multiforme (GBM) is the most lethal brain tumor and notorious for its resistance to ionizing radiation (IR). Recent evidence suggests that one possible mechanism that enables resistance to IR and protects cells against therapeutic stress is cellular autophagy. The molecular basis for this pro-survival function, however, remains elusive. Herein, we report a molecular mechanism by which IR-induced autophagy accelerates the repair of DNA double-strand breaks (DSB). We demonstrate that IR induces the accumulation of autophagosomes, which is accompanied by elevated expression of autophagyrelated genes beclin-1, atg5, atg7, and atg12. Beclin-1 knockdown impaired the induction of IR-mediated autophagy and significantly sensitized glioma cells to radiation therapy in vitro and in vivo. Furthermore, our data is the first to demonstrate that the radiosensitizing effect of beclin-1 knockdown may result from the disruption of nuclear translocation and DNA binding activity of Ku proteins and consequent attenuation of DSB repair. Our findings help advance our understanding of the molecular mechanisms underlying IR-induced autophagy and provide a promising adjunctive therapeutic strategy for the radiosensitization of malignant glioma.

  18. De-phosphorylation of translation initiation factor 2α (eIF2α) enhances glucose tolerance and attenuates hepato-steatosis in mice

    PubMed Central

    Oyadomari, Seiichi; Harding, Heather P.; Zhang, Yuhong; Oyadomari, Miho; Ron, David

    2008-01-01

    Summary The molecular mechanisms linking the stress of unfolded proteins in the endoplasmic reticulum (ER stress) to glucose intolerance in obese animals are poorly understood. In this study enforced expression of a translation initiation 2α(eIF2α)-specific phosphatase, GADD34, was used to selectively compromise signaling in the eIF2(αP)-dependent arm of the ER unfolded protein response in liver of transgenic mice. The transgene resulted in lower liver glycogen levels and susceptibility to fasting hypoglycemia in lean mice and glucose tolerance and diminished hepato-steatosis in animals fed a high fat diet. Attenuated eIF2(αP) correlated with lower expression of the adipogenic nuclear receptor PPARγ and its upstream regulators, the transcription factors C/EBPα and C/EBPβ, in transgenic mouse liver, whereas eIF2α phosphorylation promoted C/EBP translation in cultured cells and primary hepatocytes. These observations suggest that eIF2(αP)-mediated translation of key hepatic transcriptional regulators of intermediary metabolism contributes to the detrimental consequences of nutrient excess. PMID:18522833

  19. Resveratrol Attenuates Subacute Systemic Inflammation-Induced Spatial Memory Impairment via Inhibition of Astrocyte Activation and Enhancement of Synaptophysin Expression in the Hippocampus.

    PubMed

    Chen, Ying-Ying; Zhang, Li; Shi, Dong-Ling; Song, Xing-Hui; Shen, Yue-Liang; Zheng, Ming-Zhi; Wang, Lin-Lin

    2017-01-01

    The aim of this study was to investigate the role of resveratrol on subacute systemic inflammation-induced dysfunction of cognitive memory in mice and its underlying mechanism. Male ICR mice were trained in a water maze for four days of acquisition training and one day of probe trial. Subacute treatment with lipopolysaccharide (LPS) (1 mg/kg) by intraperitoneal injection for 5 days was used to establish a systemic inflammatory model. All mice were sacrificed after probe testing, then the expression of glial fibrillary acidic protein (GFAP), synaptophysin, and sirtuin1 (SIRT1) in hippocampi were determined using immunohistochemistry or western blot analysis. Morris water maze tests indicated that hippocampus-dependent spatial learning and memory were impaired in LPS-treated group. Resveratrol attenuated LPS-induced memory deficit in dose-dependent manner. Immunohistochemistry and western blot analysis revealed that LPS increased hippocampal GFAP expression and inhibited synaptophysin expression, which were prevented by resveratrol treatment. Treatment with LPS declined the SIRT1 protein expression in the hippocampus, which could be prevented by resveratrol. The protective effect of resveratrol could be abolished by a specific SIRT1 inhibitor. Our findings add new experimental data for potential therapeutic effects of resveratrol in the brain in a model of subacute systemic inflammation-induced astrocyte activation, synaptic alteration and cognitive decline.

  20. Tracer attenuation in groundwater

    NASA Astrophysics Data System (ADS)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  1. 14 CFR 23.3 - Airplane categories.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Airplane categories. 23.3 Section 23.3... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES General § 23.3 Airplane categories. (a) The normal category is limited to airplanes that have a seating configuration, excluding...

  2. 14 CFR 23.3 - Airplane categories.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Airplane categories. 23.3 Section 23.3... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES General § 23.3 Airplane categories. (a) The normal category is limited to airplanes that have a seating configuration, excluding...

  3. The Role of Corticostriatal Systems in Speech Category Learning.

    PubMed

    Yi, Han-Gyol; Maddox, W Todd; Mumford, Jeanette A; Chandrasekaran, Bharath

    2016-04-01

    One of the most difficult category learning problems for humans is learning nonnative speech categories. While feedback-based category training can enhance speech learning, the mechanisms underlying these benefits are unclear. In this functional magnetic resonance imaging study, we investigated neural and computational mechanisms underlying feedback-dependent speech category learning in adults. Positive feedback activated a large corticostriatal network including the dorsolateral prefrontal cortex, inferior parietal lobule, middle temporal gyrus, caudate, putamen, and the ventral striatum. Successful learning was contingent upon the activity of domain-general category learning systems: the fast-learning reflective system, involving the dorsolateral prefrontal cortex that develops and tests explicit rules based on the feedback content, and the slow-learning reflexive system, involving the putamen in which the stimuli are implicitly associated with category responses based on the reward value in feedback. Computational modeling of response strategies revealed significant use of reflective strategies early in training and greater use of reflexive strategies later in training. Reflexive strategy use was associated with increased activation in the putamen. Our results demonstrate a critical role for the reflexive corticostriatal learning system as a function of response strategy and proficiency during speech category learning.

  4. Enhanced motivation for food reward induced by stress and attenuation by corticotrophin-releasing factor receptor antagonism in rats: implications for overeating and obesity

    PubMed Central

    Liu, Xiu

    2014-01-01

    Rationale Overeating beyond individuals’ homeostatic needs critically contributes to obesity. The neurobehavioral mechanisms underlying the motivation to consume excessive foods with high calories are not fully understood. Objective The present study examined whether a pharmacological stressor, yohimbine enhances the motivation to procure food reward with an emphasis on comparisons between standard lab chow and high-fat foods. The effects of corticotropin-releasing factor receptor (CRF1) blockade by a CFR1 selective antagonist NBI on the stress-enhanced motivation for food reward were also assessed. Methods Male Sprague-Dawley rats with chow available ad libitum in their home cages were trained to press a lever under a progressive-ratio schedule for deliveries of either standard or high-fat food pellets. For testing yohimbine stress effects, rats received an intraperitoneal administration of yohimbine 10 min before start of the test sessions. For testing effects of CRF1 receptor blockade on stress responses, NBI was administered 20 min prior to yohimbine challenge. Results The rats emitted higher levels of lever responses to procure the high-fat food pellets compared with their counterparts on standard food pellets. Yohimbine challenge facilitated lever responses for the reward in all of the rats, whereas the effect was more robust in the rats on high-fat food pellets compared with their counterparts on standard food pellets. An inhibitory effect of pretreatment with NBI was observed on the enhancing effect of yohimbine challenge but not on the responses under baseline condition without yohimbine administration. Conclusions Stress challenge significantly enhanced the motivation of satiated rats to procure extra food reward, especially the high-fat food pellets. Activation of CRF1 receptors is required for the stress-enhanced motivation for food reward. These results may have implications for our better understanding of the biobehavioral mechanisms of overeating

  5. CTLA-4 blockade enhances the therapeutic effect of an attenuated poxvirus vaccine targeting p53 in an established murine tumor model.

    PubMed

    Espenschied, Jonathan; Lamont, Jeffrey; Longmate, Jeff; Pendas, Solange; Wang, Zhongde; Diamond, Don J; Ellenhorn, Joshua D I

    2003-03-15

    p53 is overexpressed by half of all cancers, and is an attractive target for a vaccine approach to immunotherapy. p53 overexpression is frequently the result of point mutations, which leaves the majority of the protein in its wild-type form. Therefore, the majority of p53 sequence is wild type, making it a self-protein for which tolerance plays a role in limiting immune responses. To overcome tolerance to p53, we have expressed wild-type murine p53 in the nonpathogenic attenuated poxvirus, modified vaccinia virus Ankara (recombinant modified vaccinia virus Ankara expressing wild-type murine p53 (rMVAp53)). Mice immunized with rMVAp53 vaccine developed vigorous p53-specific CTL responses. rMVAp53 vaccine was evaluated for its ability to inhibit the outgrowth of the syngeneic murine sarcoma Meth A, which overexpresses mutant p53. Mice were inoculated with a lethal dose (5 x 10(5) cells injected s.c.) of Meth A tumor cells and vaccinated by i.p. injection 3 days later with 5 x 10(7) PFU of rMVAp53. The majority of mice remained tumor free and resistant to rechallenge with Meth A tumor cells. We wished to determine whether rMVAp53 immunization could effect the rejection of an established, palpable Meth A tumor. In subsequent experiments, mice were injected with 10(6) Meth A tumor cells, and treated 6 days later with anti-CTLA-4 Ab (9H10) and rMVAp53. The majority of treated mice had complete tumor regression along with lasting tumor immunity. In vivo Ab depletion confirmed that the antitumor effect was primarily CD8 and to a lesser extent CD4 dependent. These experiments demonstrate the potential of a novel cell-free vaccine targeting p53 in malignancy.

  6. Nanowired Delivery of Growth Hormone Attenuates Pathophysiology of Spinal Cord Injury and Enhances Insulin-Like Growth Factor-1 Concentration in the Plasma and the Spinal Cord.

    PubMed

    Muresanu, Dafin F; Sharma, Aruna; Lafuente, José V; Patnaik, Ranjana; Tian, Z Ryan; Nyberg, Fred; Sharma, Hari S

    2015-10-01

    Previous studies from our laboratory showed that topical application of growth hormone (GH) induced neuroprotection 5 h after spinal cord injury (SCI) in a rat model. Since nanodelivery of drugs exerts superior neuroprotective effects, a possibility exists that nanodelivery of GH will induce long-term neuroprotection after a focal SCI. SCI induces GH deficiency that is coupled with insulin-like growth factor-1 (IGF-1) reduction in the plasma. Thus, an exogenous supplement of GH in SCI may enhance the IGF-1 levels in the cord and induce neuroprotection. In the present investigation, we delivered TiO2-nanowired growth hormone (NWGH) after a longitudinal incision of the right dorsal horn at the T10-11 segments in anesthetized rats and compared the results with normal GH therapy on IGF-1 and GH contents in the plasma and in the cord in relation to blood-spinal cord barrier (BSCB) disruption, edema formation, and neuronal injuries. Our results showed a progressive decline in IGF-1 and GH contents in the plasma and the T9 and T12 segments of the cord 12 and 24 h after SCI. Marked increase in the BSCB breakdown, as revealed by extravasation of Evans blue and radioiodine, was seen at these time points after SCI in association with edema and neuronal injuries. Administration of NWGH markedly enhanced the IGF-1 levels and GH contents in plasma and cord after SCI, whereas normal GH was unable to enhance IGF-1 or GH levels 12 or 24 h after SCI. Interestingly, NWGH was also able to reduce BSCB disruption, edema formation, and neuronal injuries after trauma. On the other hand, normal GH was ineffective on these parameters at all time points examined. Taken together, our results are the first to demonstrate that NWGH is quite effective in enhancing IGF-1 and GH levels in the cord and plasma that may be crucial in reducing pathophysiology of SCI.

  7. PPARγ-induced upregulation of CD36 enhances hematoma resolution and attenuates long-term neurological deficits after germinal matrix hemorrhage in neonatal rats.

    PubMed

    Flores, Jerry J; Klebe, Damon; Rolland, William B; Lekic, Tim; Krafft, Paul R; Zhang, John H

    2016-03-01

    Germinal matrix hemorrhage remains the leading cause of morbidity and mortality in preterm infants in the United States with little progress made in its clinical management. Survivors are often afflicted with long-term neurological sequelae, including cerebral palsy, mental retardation, hydrocephalus, and psychiatric disorders. Blood clots disrupting normal cerebrospinal fluid circulation and absorption after germinal matrix hemorrhage are thought to be important contributors towards post-hemorrhagic hydrocephalus development. We evaluated if upregulating CD36 scavenger receptor expression in microglia and macrophages through PPARγ stimulation, which was effective in experimental adult cerebral hemorrhage models and is being evaluated clinically, will enhance hematoma resolution and ameliorate long-term brain sequelae using a neonatal rat germinal matrix hemorrhage model. PPARγ stimulation (15d-PGJ2) increased short-term PPARγ and CD36 expression levels as well as enhanced hematoma resolution, which was reversed by a PPARγ antagonist (GW9662) and CD36 siRNA. PPARγ stimulation (15d-PGJ2) also reduced long-term white matter loss and post-hemorrhagic ventricular dilation as well as improved neurofunctional outcomes, which were reversed by a PPARγ antagonist (GW9662). PPARγ-induced upregulation of CD36 in macrophages and microglia is, therefore, critical for enhancing hematoma resolution and ameliorating long-term brain sequelae.

  8. PPARγ-induced Upregulation of CD36 Enhances Hematoma Resolution and Attenuates Long-term Neurological Deficits after Germinal Matrix Hemorrhage in Neonatal Rats

    PubMed Central

    Flores, Jerry J.; Klebe, Damon; Rolland, William B.; Lekic, Tim; Krafft, Paul R.; Zhang, John H.

    2016-01-01

    Germinal matrix hemorrhage remains the leading cause of morbidity and mortality in preterm infants in the United States with little progress made in its clinical management. Survivors are often afflicted with long-term neurological sequelae, including cerebral palsy, mental retardation, hydrocephalus, and psychiatric disorders. Blood clots disrupting normal cerebrospinal fluid circulation and absorption after germinal matrix hemorrhage are thought to be important contributors towards post-hemorrhagic hydrocephalus development. We evaluated if upregulating CD36 scavenger receptor expression in microglia and macrophages through PPARγ stimulation, which was effective in experimental adult cerebral hemorrhage models and is being evaluated clinically, will enhance hematoma resolution and ameliorate long-term brain sequelae using a neonatal rat germinal matrix hemorrhage model. PPARγ stimulation (15d-PGJ2) increased short-term PPARγ and CD36 expression levels as well as enhanced hematoma resolution, which was reversed by a PPARγ antagonist (GW9662) and CD36 siRNA. PPARγ stimulation (15d-PGJ2) also reduced long-term white matter loss and post-hemorrhagic ventricular dilation as well as improved neurofunctional outcomes, which were reversed by a PPARγ antagonist (GW9662). PPARγ-induced upregulation of CD36 in macrophages and microglia is, therefore, critical for enhancing hematoma resolution and ameliorating long-term brain sequelae. PMID:26739391

  9. Activation of KCNN3/SK3/K(Ca)2.3 channels attenuates enhanced calcium influx and inflammatory cytokine production in activated microglia.

    PubMed

    Dolga, Amalia M; Letsche, Till; Gold, Maike; Doti, Nunzianna; Bacher, Michael; Chiamvimonvat, Nipavan; Dodel, Richard; Culmsee, Carsten

    2012-12-01

    In neurons, small-conductance calcium-activated potassium (KCNN/SK/K(Ca)2) channels maintain calcium homeostasis after N-methyl-D-aspartate (NMDA) receptor activation, thereby preventing excitotoxic neuronal death. So far, little is known about the function of KCNN/SK/K(Ca)2 channels in non-neuronal cells, such as microglial cells. In this study, we addressed the question whether KCNN/SK/K(Ca)2 channels activation affected inflammatory responses of primary mouse microglial cells upon lipopolysaccharide (LPS) stimulation. We found that N-cyclohexyl-N-[2-(3,5-dimethyl-pyrazol-1-yl)-6-methyl-4-pyrimidinamine (CyPPA), a positive pharmacological activator of KCNN/SK/K(Ca)2 channels, significantly reduced LPS-stimulated activation of microglia in a concentration-dependent manner. The general KCNN/SK/K(Ca)2 channel blocker apamin reverted these effects of CyPPA on microglial proliferation. Since calcium plays a central role in microglial activation, we further addressed whether KCNN/SK/K(Ca)2 channel activation affected the changes of intracellular calcium levels, [Ca(2+)](i), in microglial cells. Our data show that LPS-induced elevation of [Ca(2+)](i) was attenuated following activation of KCNN2/3/K(Ca)2.2/K(Ca)2.3 channels by CyPPA. Furthermore, CyPPA reduced downstream events including tumor necrosis factor alpha and interleukin 6 cytokine production and nitric oxide release in activated microglia. Further, we applied specific peptide inhibitors of the KCNN/SK/K(Ca)2 channel subtypes to identify which particular channel subtype mediated the observed anti-inflammatory effects. Only inhibitory peptides targeting KCNN3/SK3/K(Ca)2.3 channels, but not KCNN2/SK2/K(Ca)2.2 channel inhibition, reversed the CyPPA-effects on LPS-induced microglial proliferation. These findings revealed that KCNN3/SK3/K(Ca)2.3 channels can modulate the LPS-induced inflammatory responses in microglial cells. Thus, KCNN3/SK3/K(Ca)2.3 channels may serve as a therapeutic target for reducing microglial

  10. High glutamate attenuates S100B and LDH outputs from rat cortical slices enhanced by either oxygen-glucose deprivation or menadione.

    PubMed

    Demircan, Celaleddin; Gül, Zülfiye; Büyükuysal, R Levent

    2014-07-01

    One hour incubation of rat cortical slices in a medium without oxygen and glucose (oxygen-glucose deprivation, OGD) increased S100B release to 6.53 ± 0.3 ng/ml/mg protein from its control value of 3.61 ± 0.2 ng/ml/mg protein. When these slices were then transferred to a medium containing oxygen and glucose (reoxygenation, REO), S100B release rose to 344 % of its control value. REO also caused 192 % increase in lactate dehydrogenase (LDH) leakage. Glutamate added at millimolar concentration into the medium decreased OGD or REO-induced S100B release and REO-induced LDH leakage. Alpha-ketoglutarate, a metabolic product of glutamate, was found to be as effective as glutamate in decreasing the S100B and LDH outputs. Similarly lactate, 2-ketobutyrate and ethyl pyruvate, a lipophilic derivative of pyruvate, also exerted a glutamate-like effect on S100B and LDH outputs. Preincubation with menadione, which produces H2O2 intracellularly, significantly increased S100B and LDH levels in normoxic medium. All drugs tested in the present study, with the exception of pyruvate, showed a complete protection against menadione preincubation. Additionally, each OGD-REO, menadione or H2O2-induced mitochondrial energy impairments determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining and OGD-REO or menadione-induced increases in reactive oxygen substances (ROS) determined by 2,7-dichlorofluorescin diacetate (DCFH-DA) were also recovered by glutamate. Interestingly, H2O2-induced increase in fluorescence intensity derived from DCFH-DA in a slice-free physiological medium was attenuated significantly by glutamate and alpha-keto acids. All these drug actions support the conclusion that high glutamate, such as alpha-ketoglutarate and other keto acids, protects the slices against OGD- and REO-induced S100B and LDH outputs probably by scavenging ROS in addition to its energy substrate metabolite property.

  11. The let-7 microRNA enhances heme oxygenase-1 by suppressing Bach1 and attenuates oxidant injury in human hepatocytes.

    PubMed

    Hou, Weihong; Tian, Qing; Steuerwald, Nury M; Schrum, Laura W; Bonkovsky, Herbert L

    2012-01-01

    The let-7 microRNA (miRNA) plays important roles in human liver development and diseases such as hepatocellular carcinoma, liver fibrosis and hepatitis wherein oxidative stress accelerates the progression of these diseases. To date, the role of the let-7 miRNA family in modulation of heme oxygenase 1 (HMOX1), a key cytoprotective enzyme, remains unknown. Our aims were to determine whether let-7 miRNA directly regulates Bach1, a transcriptional repressor of the HMOX1 gene, and whether indirect up-regulation of HMOX1 by let-7 miRNA attenuates oxidant injury in human hepatocytes. The effects of let-7 miRNA on Bach1 and HMOX1 gene expression in Huh-7 and HepG2 cells were determined by real-time qRT-PCR, Western blot, and luciferase reporter assays. Dual luciferase reporter assays revealed that let-7b, let-7c, or miR-98 significantly decreased Bach1 3'-untranslated region (3'-UTR)-dependent luciferase activity but not mutant Bach1 3'-UTR-dependent luciferase activity, whereas mutant let-7 miRNA containing base complementarity with mutant Bach1 3'-UTR restored its effect on mutant reporter activity. let-7b, let-7c, or miR-98 down-regulated Bach1 protein levels by 50-70%, and subsequently up-regulated HMOX1 gene expression by 3-4 fold, compared with non-specific controls. Furthermore, Huh-7 cells transfected with let-7b, let-7c or miR-98 mimic showed increased resistance against oxidant injury induced by tert-butyl-hydroperoxide (tBuOOH), whereas the protection was abrogated by over-expression of Bach1. In conclusion, let-7 miRNA directly acts on the 3'-UTR of Bach1 and negatively regulates expression of this protein, and thereby up-regulates HMOX1 gene expression. Over-expression of the let-7 miRNA family members may represent a novel approach to protecting human hepatocytes from oxidant injury.

  12. HERC2 rs12913832 modulates human pigmentation by attenuating chromatin-loop formation between a long-range enhancer and the OCA2 promoter

    PubMed Central

    Visser, Mijke; Kayser, Manfred; Palstra, Robert-Jan

    2012-01-01

    Pigmentation of skin, eye, and hair reflects some of the most evident common phenotypes in humans. Several candidate genes for human pigmentation are identified. The SNP rs12913832 has strong statistical association with human pigmentation. It is located within an intron of the nonpigment gene HERC2, 21 kb upstream of the pigment gene OCA2, and the region surrounding rs12913832 is highly conserved among animal species. However, the exact functional role of HERC2 rs12913832 in human pigmentation is unknown. Here we demonstrate that the HERC2 rs12913832 region functions as an enhancer regulating OCA2 transcription. In darkly pigmented human melanocytes carrying the rs12913832 T-allele, we detected binding of the transcription factors HLTF, LEF1, and MITF to the HERC2 rs12913832 enhancer, and a long-range chromatin loop between this enhancer and the OCA2 promoter that leads to elevated OCA2 expression. In contrast, in lightly pigmented melanocytes carrying the rs12913832 C-allele, chromatin-loop formation, transcription factor recruitment, and OCA2 expression are all reduced. Hence, we demonstrate that allelic variation of a common noncoding SNP located in a distal regulatory element not only disrupts the regulatory potential of this element but also affects its interaction with the relevant promoter. We provide the key mechanistic insight that allele-dependent differences in chromatin-loop formation (i.e., structural differences in the folding of gene loci) result in differences in allelic gene expression that affects common phenotypic traits. This concept is highly relevant for future studies aiming to unveil the functional basis of genetically determined phenotypes, including diseases. PMID:22234890

  13. Bioconjugated Manganese Dioxide Nanoparticles Enhance Chemotherapy Response by Priming Tumor-Associated Macrophages toward M1-like Phenotype and Attenuating Tumor Hypoxia

    PubMed Central

    Shi, Changrong; Zhang, Xiangzhong; Chen, Xiaoyuan

    2017-01-01

    Hypoxia promotes not only the invasiveness of tumor cells, but also chemoresistance in cancer. Tumor associated macrophages (TAMs) residing at the site of hypoxic region of tumors have been known to cooperate with tumor cells, and promote proliferation and chemoresistance. Therefore, there is an urgent need for new strategies to alleviate tumor hypoxia and enhance chemotherapy response in solid tumors. Herein, we have taken advantage of high accumulation of TAMs in hypoxic regions of tumor and high reactivity of manganese dioxide nanoparticles (MnO2 NPs) toward hydrogen peroxide (H2O2) for the simultaneous production of O2 and regulation of pH to effectively alleviate tumor hypoxia by targeted delivery of MnO2 NPs to the hypoxic area. Furthermore, we also utilized the ability of hyaluronic acid (HA) modification in reprogramming anti-inflammatory, pro-tumoral M2 TAMs to pro-inflammatory, antitumor M1 macrophages to further enhance the ability of MnO2 NPs to lessen tumor hypoxia and modulate chemoresistance. The HA-coated, mannanconjugated MnO2 particle (Man-HA-MnO2) treatment significantly increased tumor oxygenation and down-regulated hypoxia-inducible factor-1 α (HIF-1α) and vascular endothelial growth factor (VEGF) in the tumor. Combination treatment of the tumors with Man-HA-MnO2 NPs and doxorubicin significantly increased apparent diffusion coefficient (ADC) values of breast tumor, inhibited tumor growth and tumor cell proliferation as compared with chemotherapy alone. In addition, the reaction of Man-HA-MnO2 NPs toward endogenous H2O2 highly enhanced T1- and T2-MRI performance for tumor imaging and detection. PMID:26650065

  14. HERC2 rs12913832 modulates human pigmentation by attenuating chromatin-loop formation between a long-range enhancer and the OCA2 promoter.

    PubMed

    Visser, Mijke; Kayser, Manfred; Palstra, Robert-Jan

    2012-03-01

    Pigmentation of skin, eye, and hair reflects some of the most evident common phenotypes in humans. Several candidate genes for human pigmentation are identified. The SNP rs12913832 has strong statistical association with human pigmentation. It is located within an intron of the nonpigment gene HERC2, 21 kb upstream of the pigment gene OCA2, and the region surrounding rs12913832 is highly conserved among animal species. However, the exact functional role of HERC2 rs12913832 in human pigmentation is unknown. Here we demonstrate that the HERC2 rs12913832 region functions as an enhancer regulating OCA2 transcription. In darkly pigmented human melanocytes carrying the rs12913832 T-allele, we detected binding of the transcription factors HLTF, LEF1, and MITF to the HERC2 rs12913832 enhancer, and a long-range chromatin loop between this enhancer and the OCA2 promoter that leads to elevated OCA2 expression. In contrast, in lightly pigmented melanocytes carrying the rs12913832 C-allele, chromatin-loop formation, transcription factor recruitment, and OCA2 expression are all reduced. Hence, we demonstrate that allelic variation of a common noncoding SNP located in a distal regulatory element not only disrupts the regulatory potential of this element but also affects its interaction with the relevant promoter. We provide the key mechanistic insight that allele-dependent differences in chromatin-loop formation (i.e., structural differences in the folding of gene loci) result in differences in allelic gene expression that affects common phenotypic traits. This concept is highly relevant for future studies aiming to unveil the functional basis of genetically determined phenotypes, including diseases.

  15. Oral administration of Lactobacillus paracasei L9 attenuates PM2.5-induced enhancement of airway hyperresponsiveness and allergic airway response in murine model of asthma

    PubMed Central

    Zhao, Liang; Hao, Yanling; Guo, Huiyuan; Ren, Fazheng

    2017-01-01

    This study investigated allergy immunotherapy potential of Lactobacillus paracasei L9 to prevent or mitigate the particulate matter 2.5 (PM2.5) enhanced pre-existing asthma in mice. Firstly, we used a mouse model of asthma (a 21-day ovalbumin (OVA) sensitization and challenge model) followed by PM2.5 exposure twice on the same day of the last challenge. PM2.5 was collected from the urban area of Beijing and underwent analysis for metals and polycyclic aromatic hydrocarbon contents. The results showed that PM2.5 exposure enhanced airway hyper-responsiveness (AHR) and lead to a mixed Th2/ IL-17 response in asthmatic mice. Secondly, the PM2.5 exposed asthmatic mice were orally administered with L9 (4×107, 4×109 CFU/mouse, day) from the day of first sensitization to the endpoint, for 20 days, to investigate the potential mitigative effect of L9 on asthma. The results showed that L9 ameliorated PM2.5 exposure enhanced AHR with an approximate 50% decrease in total airway resistance response to methacholine (48 mg/ml). L9 also prevented the exacerbated eosinophil and neutrophil infiltration in bronchoalveolar lavage fluid (BALF), and decreased the serum level of total IgE and OVA-specific IgG1 by 0.44-fold and 0.3-fold, respectively. Additionally, cytokine production showed that L9 significantly decreased T-helper cell type 2 (Th2)–related cytokines (IL-4, -5, -13) and elevated levels of Th1 related IFN-γ in BALF. L9 also reduced the level of IL-17A and increased the level of TGF-β. Taken together, these results indicate that L9 may exert the anti-allergic benefit, possibly through rebalancing Th1/Th2 immune response and modulating IL-17 pro-inflammatory immune response. Thus, L9 is a promising candidate for preventing PM exposure enhanced pre-existing asthma. PMID:28199353

  16. Oral administration of Lactobacillus paracasei L9 attenuates PM2.5-induced enhancement of airway hyperresponsiveness and allergic airway response in murine model of asthma.

    PubMed

    Wang, Xifan; Hui, Yan; Zhao, Liang; Hao, Yanling; Guo, Huiyuan; Ren, Fazheng

    2017-01-01

    This study investigated allergy immunotherapy potential of Lactobacillus paracasei L9 to prevent or mitigate the particulate matter 2.5 (PM2.5) enhanced pre-existing asthma in mice. Firstly, we used a mouse model of asthma (a 21-day ovalbumin (OVA) sensitization and challenge model) followed by PM2.5 exposure twice on the same day of the last challenge. PM2.5 was collected from the urban area of Beijing and underwent analysis for metals and polycyclic aromatic hydrocarbon contents. The results showed that PM2.5 exposure enhanced airway hyper-responsiveness (AHR) and lead to a mixed Th2/ IL-17 response in asthmatic mice. Secondly, the PM2.5 exposed asthmatic mice were orally administered with L9 (4×107, 4×109 CFU/mouse, day) from the day of first sensitization to the endpoint, for 20 days, to investigate the potential mitigative effect of L9 on asthma. The results showed that L9 ameliorated PM2.5 exposure enhanced AHR with an approximate 50% decrease in total airway resistance response to methacholine (48 mg/ml). L9 also prevented the exacerbated eosinophil and neutrophil infiltration in bronchoalveolar lavage fluid (BALF), and decreased the serum level of total IgE and OVA-specific IgG1 by 0.44-fold and 0.3-fold, respectively. Additionally, cytokine production showed that L9 significantly decreased T-helper cell type 2 (Th2)-related cytokines (IL-4, -5, -13) and elevated levels of Th1 related IFN-γ in BALF. L9 also reduced the level of IL-17A and increased the level of TGF-β. Taken together, these results indicate that L9 may exert the anti-allergic benefit, possibly through rebalancing Th1/Th2 immune response and modulating IL-17 pro-inflammatory immune response. Thus, L9 is a promising candidate for preventing PM exposure enhanced pre-existing asthma.

  17. The Serotonin 2C Receptor Agonist Lorcaserin Attenuates Intracranial Self-Stimulation and Blocks the Reward-Enhancing Effects of Nicotine.

    PubMed

    Zeeb, Fiona D; Higgins, Guy A; Fletcher, Paul J

    2015-07-15

    Lorcaserin, a serotonin (5-hydroxytryptamine, 5-HT) 2C receptor agonist, was recently approved for the treatment of obesity. We previously suggested that 5-HT2C receptor agonists affect reward processes and reduce the rewarding effects of drugs of abuse. Here, we determined whether lorcaserin (1) decreases responding for brain stimulation reward (BSR) and (2) prevents nicotine from enhancing the efficacy of BSR. Rats were trained on the intracranial self-stimulation (ICSS) paradigm to nosepoke for BSR of either the dorsal raphé nucleus or left medial forebrain bundle. In Experiment 1, lorcaserin (0.3-1.0 mg/kg) dose-dependently reduced the efficacy of BSR. This effect was blocked by prior administration of the 5-HT2C receptor antagonist SB242084. In Experiment 2, separate groups of rats received saline or nicotine (0.4 mg/kg) for eight sessions prior to testing. Although thresholds were unaltered in saline-treated rats, nicotine reduced reward thresholds. An injection of lorcaserin (0.3 mg/kg) prior to nicotine prevented the reward-enhancing effect of nicotine across multiple test sessions. These results demonstrated that lorcaserin reduces the rewarding value of BSR and also prevents nicotine from facilitating ICSS. Hence, lorcaserin may be effective in treating psychiatric disorders, including obesity and nicotine addiction, by reducing the value of food or drug rewards.

  18. Within-Category Discontinuity Interacts with Verbal Rule Complexity in Perceptual Category Learning

    ERIC Educational Resources Information Center

    Maddox, W. Todd; Filoteo, J. Vincent; Lauritzen, J. Scott

    2007-01-01

    A test of the predicted interaction between within-category discontinuity and verbal rule complexity on information-integration and rule-based category learning was conducted. Within-category discontinuity adversely affected information-integration category learning but not rule-based category learning. Model-based analyses suggested that some…

  19. Variable laser attenuator

    DOEpatents

    Foltyn, Stephen R.

    1988-01-01

    The disclosure relates to low loss, high power variable attenuators comprng one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength.

  20. Variable laser attenuator

    DOEpatents

    Foltyn, S.R.

    1987-05-29

    The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

  1. Foxp3(+)-Treg cells enhanced by repeated low-dose gamma-irradiation attenuate ovalbumin-induced allergic asthma in mice.

    PubMed

    Park, Bum Soo; Hong, Gwan Ui; Ro, Jai Youl

    2013-05-01

    Gamma radiation is used for several therapeutic indications such as cancers and autoimmune diseases. Low-dose whole-body γ irradiation has been shown to activate immune responses in several ways, however, the effect and mechanism of irradiation on allergic asthma remains poorly understood. This study investigated whether or not irradiation exacerbates allergic asthma responses and its potential mechanism. C57BL/6 mice were sensitized and challenged with ovalbumin (OVA) to induce asthma. The mice received whole-body irradiation once daily for 3 consecutive days with a dose of 0.667 Gy using (137)Cs γ rays 24 h before every OVA challenge. Repeated low-dose irradiation reduced OVA-specific IgE levels, the number of inflammatory cells including mast cells, goblet cell hyperplasia, collagen deposition, airway hyperresponsiveness, expression of inflammatory cytokines, CCL2/CCR2, as well as nuclear factor kappa B (NF-κB) and activator protein-1 activities. All of these factors were increased in BAL cells and lung tissue of OVA-challenged mice. Irradiation increased the number of Treg cells, expression of interleukin (IL)-10, IL-2 and IL-35 in BAL cells and lung tissue. Irradiation also increased Treg cell-expressed Foxp3 and IL-10 by NF-κB and RUNX1 in OVA-challenged mice. Furthermore, while Treg cell-expressing OX40 and IL-10 were enhanced in lung tissue or act-bone marrow-derived mast cells (BMMCs) with Treg cells, but BMMCs-expressing OX40L and TGF-β were decreased. The data suggest that irradiation enhances Foxp3(+)- and IL-10-producing Treg cells, which reduce OVA-induced allergic airway inflammation and tissue remodeling through the down-regulation of migration by the CCL2/CCR2 axis and activation of mast cells via OX40/OX40L in lung tissue of OVA-challenged mice.

  2. Effect of explicit dimension instruction on speech category learning

    PubMed Central

    Chandrasekaran, Bharath; Yi, Han-Gyol; Smayda, Kirsten E.; Maddox, W. Todd

    2015-01-01

    Learning non-native speech categories is often considered a challenging task in adulthood. This difficulty is driven by cross-language differences in weighting critical auditory dimensions that differentiate speech categories. For example, previous studies have shown that differentiating Mandarin tonal categories requires attending to dimensions related to pitch height and direction. Relative to native speakers of Mandarin, the pitch direction dimension is under-weighted by native English speakers. In the current study, we examined the effect of explicit instructions (dimension instruction) on native English speakers' Mandarin tone category learning within the framework of a dual-learning systems (DLS) model. This model predicts that successful speech category learning is initially mediated by an explicit, reflective learning system that frequently utilizes unidimensional rules, with an eventual switch to a more implicit, reflexive learning system that utilizes multidimensional rules. Participants were explicitly instructed to focus and/or ignore the pitch height dimension, the pitch direction dimension, or were given no explicit prime. Our results show that instruction instructing participants to focus on pitch direction, and instruction diverting attention away from pitch height resulted in enhanced tone categorization. Computational modeling of participant responses suggested that instruction related to pitch direction led to faster and more frequent use of multidimensional reflexive strategies, and enhanced perceptual selectivity along the previously underweighted pitch direction dimension. PMID:26542400

  3. Effect of explicit dimensional instruction on speech category learning.

    PubMed

    Chandrasekaran, Bharath; Yi, Han-Gyol; Smayda, Kirsten E; Maddox, W Todd

    2016-02-01

    Learning nonnative speech categories is often considered a challenging task in adulthood. This difficulty is driven by cross-language differences in weighting critical auditory dimensions that differentiate speech categories. For example, previous studies have shown that differentiating Mandarin tonal categories requires attending to dimensions related to pitch height and direction. Relative to native speakers of Mandarin, the pitch direction dimension is underweighted by native English speakers. In the current study, we examined the effect of explicit instructions (dimension instruction) on native English speakers' Mandarin tone category learning within the framework of a dual-learning systems (DLS) model. This model predicts that successful speech category learning is initially mediated by an explicit, reflective learning system that frequently utilizes unidimensional rules, with an eventual switch to a more implicit, reflexive learning system that utilizes multidimensional rules. Participants were explicitly instructed to focus and/or ignore the pitch height dimension, the pitch direction dimension, or were given no explicit prime. Our results show that instruction instructing participants to focus on pitch direction, and instruction diverting attention away from pitch height, resulted in enhanced tone categorization. Computational modeling of participant responses suggested that instruction related to pitch direction led to faster and more frequent use of multidimensional reflexive strategies and enhanced perceptual selectivity along the previously underweighted pitch direction dimension.

  4. Posterror slowing predicts rule-based but not information-integration category learning.

    PubMed

    Tam, Helen; Maddox, W Todd; Huang-Pollock, Cynthia L

    2013-12-01

    We examined whether error monitoring, operationalized as the degree to which individuals slow down after committing an error (i.e., posterror slowing), is differentially important in the learning of rule-based versus information-integration category structures. Rule-based categories are most efficiently solved through the application of an explicit verbal strategy (e.g., "sort by color"). In contrast, information-integration categories are believed to be learned in a trial-by-trial, associative manner. Our results indicated that posterror slowing predicts enhanced rule-based but not information-integration category learning. Implications for multiple category-learning systems are discussed.

  5. Development of essentialist thinking about religion categories in Northern Ireland (and the United States).

    PubMed

    Smyth, Kirsty; Feeney, Aidan; Eidson, R Cole; Coley, John D

    2017-03-01

    Social essentialism, the belief that members of certain social categories share unobservable properties, licenses expectations that those categories are natural and a good basis for inference. A challenge for cognitive developmental theory is to give an account of how children come to develop essentialist beliefs about socially important categories. Previous evidence from Israel suggests that kindergarteners selectively engage in essentialist reasoning about culturally salient (ethnicity) categories, and that this is attenuated among children in integrated schools. In 5 studies (N = 718) we used forced-choice (Study 1) and unconstrained (Studies 2-4) category-based inference tasks, and a questionnaire (Study 5) to study the development of essentialist reasoning about religion categories in Northern Ireland (Studies 1-3 & 5) and the U.S. (Study 4). Results show that, as in Israel, Northern Irish children selectively engage in essentialist reasoning about culturally salient (religion) categories, and that such reasoning is attenuated among children in integrated schools. However, the development trajectory of essentialist thinking and the patterns of attenuation among children attending integrated schools in Northern Ireland differ from the Israeli case. Meta-analysis confirmed this claim and ruled out an alternative explanation of the results based on community diversity. Although the Northern Irish and Israeli case studies illustrate that children develop selective essentialist beliefs about socially important categories, and that these beliefs are impacted by educational context, the differences between them emphasize the importance of historical, cultural, and political context in understanding conceptual development, and suggest that there may be more than one developmental route to social essentialism. (PsycINFO Database Record

  6. Activation of SIRT1 Attenuates Klotho Deficiency-Induced Arterial Stiffness and Hypertension by Enhancing AMP-Activated Protein Kinase Activity.

    PubMed

    Gao, Diansa; Zuo, Zhong; Tian, Jing; Ali, Quaisar; Lin, Yi; Lei, Han; Sun, Zhongjie

    2016-11-01

    Arterial stiffness is an independent risk factor for stroke and myocardial infarction. This study was designed to investigate the role of SIRT1, an important deacetylase, and its relationship with Klotho, a kidney-derived aging-suppressor protein, in the pathogenesis of arterial stiffness and hypertension. We found that the serum level of Klotho was decreased by ≈45% in patients with arterial stiffness and hypertension. Interestingly, Klotho haplodeficiency caused arterial stiffening and hypertension, as evidenced by significant increases in pulse wave velocity and blood pressure in Klotho-haplodeficient (KL(+/-)) mice. Notably, the expression and activity of SIRT1 were decreased significantly in aortic endothelial and smooth muscle cells in KL(+/-) mice, suggesting that Klotho deficiency downregulates SIRT1. Treatment with SRT1720 (15 mg/kg/d, IP), a specific SIRT1 activator, abolished Klotho deficiency-induced arterial stiffness and hypertension in KL(+/-) mice. Klotho deficiency was associated with significant decreases in activities of AMP-activated protein kinase α (AMPKα) and endothelial NO synthase (eNOS) in aortas, which were abolished by SRT1720. Furthermore, Klotho deficiency upregulated NADPH oxidase activity and superoxide production, increased collagen expression, and enhanced elastin fragmentation in the media of aortas. These Klotho deficiency-associated changes were blocked by SRT1720. In conclusion, this study provides the first evidence that Klotho deficiency downregulates SIRT1 activity in arterial endothelial and smooth muscle cells. Pharmacological activation of SIRT1 may be an effective therapeutic strategy for arterial stiffness and hypertension.

  7. The human milk oligosaccharide 2'-fucosyllactose attenuates the severity of experimental necrotising enterocolitis by enhancing mesenteric perfusion in the neonatal intestine.

    PubMed

    Good, Misty; Sodhi, Chhinder P; Yamaguchi, Yukihiro; Jia, Hongpeng; Lu, Peng; Fulton, William B; Martin, Laura Y; Prindle, Thomas; Nino, Diego F; Zhou, Qinjie; Ma, Congrong; Ozolek, John A; Buck, Rachael H; Goehring, Karen C; Hackam, David J

    2016-10-01

    Necrotising enterocolitis (NEC) is a common disease in premature infants characterised by intestinal ischaemia and necrosis. The only effective preventative strategy against NEC is the administration of breast milk, although the protective mechanisms remain unknown. We hypothesise that an abundant human milk oligosaccharide (HMO) in breast milk, 2'-fucosyllactose (2'FL), protects against NEC by enhancing intestinal mucosal blood flow, and we sought to determine the mechanisms underlying this protection. Administration of HMO-2'FL protected against NEC in neonatal wild-type mice, resulted in a decrease in pro-inflammatory markers and preserved the small intestinal mucosal architecture. These protective effects occurred via restoration of intestinal perfusion through up-regulation of the vasodilatory molecule endothelial nitric oxide synthase (eNOS), as administration of HMO-2'FL to eNOS-deficient mice or to mice that received eNOS inhibitors did not protect against NEC, and by 16S analysis HMO-2'FL affected the microbiota of the neonatal mouse gut, although these changes do not seem to be the primary mechanism of protection. Induction of eNOS by HMO-2'FL was also observed in cultured endothelial cells, providing a link between eNOS and HMO in the endothelium. These data demonstrate that HMO-2'FL protects against NEC in part through maintaining mesenteric perfusion via increased eNOS expression, and suggest that the 2'FL found in human milk may be mediating some of the protective benefits of breast milk in the clinical setting against NEC.

  8. Fucose-containing fraction of Ling-Zhi enhances lipid rafts-dependent ubiquitination of TGFβ receptor degradation and attenuates breast cancer tumorigenesis

    PubMed Central

    Tsao, Shu-Ming; Hsu, Hsien-Yeh

    2016-01-01

    Ganoderma lucidum exerts antitumor activity, but the mechanism of G. lucidum polysaccharides on cancer is unclear. Here, we demonstrated that a fucose-containing fraction of Ling-Zhi (FFLZ) reduced tumor size and suppressed metastasis in vivo. Furthermore, FFLZ inhibited breast cancer cell migration and altered the epithelial-to-mesenchymal transition (EMT) phenotype. Transforming growth factor-β receptor (TGFR) pathways act as key mediators to promote tumor progression and metastasis. We found that FFLZ down-regulated TGFR and downstream signaling pathways, including the phosphorylation of Smad2/3 and the expression of Smad4. In an investigation of the underlying mechanisms, we found that FFLZ enhanced the Smurf2-dependent ubiquitination of TGFR by disrupting the balance of the lipid rafts, promoted the “re-localization” of the TGFR to the caveolae, and facilitated the degradation of TGFR. Together, our data indicated that FFLZ is associated with the inhibition of EMT and the prevention of metastasis by promoting ubiquitination-dependent TGFR degradation and abolishing TGFR signaling pathways. Moreover, the combination of FFLZ and trastuzumab synergistically inhibited the viability of certain trastuzumab-resistant human breast cancer cells. In summary, our current findings indicate that FFLZ is a potential therapeutic or dietary supplemental agent for cancer patients and that it functions via the caveolin-1/Smad7/Smurf2-dependent ubiquitin-mediated degradation of TGFR. PMID:27830743

  9. Incremental Bayesian Category Learning from Natural Language

    ERIC Educational Resources Information Center

    Frermann, Lea; Lapata, Mirella

    2016-01-01

    Models of category learning have been extensively studied in cognitive science and primarily tested on perceptual abstractions or artificial stimuli. In this paper, we focus on categories acquired from natural language stimuli, that is, words (e.g., "chair" is a member of the furniture category). We present a Bayesian model that, unlike…

  10. What Children Infer from Social Categories

    ERIC Educational Resources Information Center

    Diesendruck, Gil; Eldror, Ehud

    2011-01-01

    Children hold the belief that social categories have essences. We investigated what kinds of properties children feel licensed to infer about a person based on social category membership. Seventy-two 4-6-year-olds were introduced to novel social categories defined as having one internal--psychological or biological--and one external--behavioral or…

  11. The Micro-Category Account of Analogy

    ERIC Educational Resources Information Center

    Green, Adam E.; Fugelsang, Jonathan A.; Kraemer, David J. M.; Dunbar, Kevin N.

    2008-01-01

    Here, we investigate how activation of mental representations of categories during analogical reasoning influences subsequent cognitive processing. Specifically, we present and test the central predictions of the "Micro-Category" account of analogy. This account emphasizes the role of categories in aligning terms for analogical mapping. In a…

  12. Melatonin attenuated adipogenesis through reduction of the CCAAT/enhancer binding protein beta by regulating the glycogen synthase 3 beta in human mesenchymal stem cells.

    PubMed

    Rhee, Yun-Hee; Ahn, Jin-Chul

    2016-06-01

    Adipogenic differentiation is characterized by an increase in two major transcription factors: peroxisome proliferator-activated receptor gamma (PPARγ) and the CCAAT/enhancer binding protein alpha (C/EBPα). These two signals are influenced by C/EBPβ and C/EBPδ and cross-regulate each other's expression during the initial stages of adipogenesis. Melatonin has been known to act as not only a direct scavenger of free radicals but also an inhibitor of glycogen synthase kinase 3β (GSK-3β). Here, we report that melatonin inhibits the adipogenic differentiation of human mesenchymal stem cells (hMSCs) which is due to the regulations of C/EBPβ in the early stage of adipogenic differentiation. Melatonin reduced the lipid accumulation, adiponectin, and lipoprotein lipase (LPL) during the adipogenic differentiation of hMSCs. Since C/EBPβ has been associated with the activation of PPARγ and the consensus site of ERK/GSK-3β, PPARγ and β-catenin were detected by immunofluorescence staining after pretreatment of melatonin. Melatonin blocked the activation of PPARγ which induced the degradation of β-catenin. Melatonin also decreased the levels of cyclic adenosine-3,5-monophosphate (cAMP) and reactive oxygen species (ROS). The cAMP triggered the activity of C/EBPβ which is a critical inducer of PPARγ and C/EBPα activation in the early stage of adipogenic differentiation, and this is further affected by ROS production. The adipogenic marker proteins such as PPARγ, C/EBPα, C/EBPβ, and pERK were also decreased by melatonin. In summary, melatonin inhibited the cAMP synthesis through ROS reduction and the phosphorylation of the ERK/GSK-3β site which is known to be responsible for C/EBPβ activation for adipogenic differentiation in hMSCs.

  13. Engineering an improved cell cycle-regulatable herpes simplex virus type 1 amplicon vector with enhanced transgene expression in proliferating cells yet attenuated activities in resting cells.

    PubMed

    Wang, Grace Y; Ho, Ivy A W; Sia, Kian C; Miao, L; Hui, Kam M; Lam, Paula Y P

    2007-03-01

    We previously generated a herpes simplex virus type 1 (HSV-1)-based amplicon vector (denoted pC8-36) in which gene expression from the minimal cyclin A promoter is repressed by preventing the binding of a trans-activating protein, Gal4-NF-YA, to it through selective interaction with the transcriptional repressor protein CDF-1. Because CDF-1 is absent in actively dividing cells, transgene expression conferred by the pC8-36 vector is therefore cell cycle dependent. As gene therapy evolves to become a promising therapeutic modality for many human diseases, there is an increasing need to further improve the kinetics of gene regulation. In the present study, we examined whether the availability of more binding sites for CDF-1 repressor proteins could enhance transgene expression. Using an overlap extension polymerase chain reaction (PCR) method, the CDE and CHR elements within the minimum cyclin A promoter were multimerized to contain two, three, and six copies of the designated CDE/CHR sequence. Interestingly, our results demonstrated that six-copy CDE/CHR sequence motifs (pC8-6CC-Luc) conferred an approximately 20-fold increase in the ratio of cell cycle regulation compared with the previous reported construct. Further, the overall transcriptional activities mediated by pC8-6CC-Luc were stronger compared with the native human survivin promoter, which consists of three copies of the CDE element and one copy of the CHR element. pC8-6CC-Luc contained, in essence, only the synthetic six-copy CDE/CHR sequence motif (about 262 bp). In comparison with other native endogenous promoters, which usually contain many other transcription binding sites, pC8-6CC-Luc amplicon vectors should confer better regulated and consistent transgene expression and may be considered a gene delivery vector of choice to target actively proliferating tumor cells.

  14. The human milk oligosaccharide 2′-fucosyllactose attenuates the severity of experimental necrotising enterocolitis by enhancing mesenteric perfusion in the neonatal intestine

    PubMed Central

    Good, Misty; Sodhi, Chhinder P.; Yamaguchi, Yukihiro; Jia, Hongpeng; Lu, Peng; Fulton, William B.; Martin, Laura Y.; Prindle, Thomas; Nino, Diego F.; Zhou, Qinjie; Ma, Congrong; Ozolek, John A.; Buck, Rachael H.; Goehring, Karen C.; Hackam, David J.

    2016-01-01

    Necrotising enterocolitis (NEC) is a common disease in premature infants characterised by intestinal ischaemia and necrosis. The only effective preventative strategy against NEC is the administration of breast milk, although the protective mechanisms remain unknown. We hypothesise that an abundant human milk oligosaccharide (HMO) in breast milk, 2′-fucosyllactose (2′FL), protects against NEC by enhancing intestinal mucosal blood flow, and we sought to determine the mechanisms underlying this protection. Administration of HMO-2′FL protected against NEC in neonatal wild-type mice, resulted in a decrease in pro-inflammatory markers and preserved the small intestinal mucosal architecture. These protective effects occurred via restoration of intestinal perfusion through up-regulation of the vasodilatory molecule endothelial nitric oxide synthase (eNOS), as administration of HMO-2′FL to eNOS-deficient mice or to mice that received eNOS inhibitors did not protect against NEC, and by 16S analysis HMO-2′FL affected the microbiota of the neonatal mouse gut, although these changes do not seem to be the primary mechanism of protection. Induction of eNOS by HMO-2′FL was also observed in cultured endothelial cells, providing a link between eNOS and HMO in the endothelium. These data demonstrate that HMO-2′FL protects against NEC in part through maintaining mesenteric perfusion via increased eNOS expression, and suggest that the 2′FL found in human milk may be mediating some of the protective benefits of breast milk in the clinical setting against NEC. PMID:27609061

  15. A history of chorological categories.

    PubMed

    Fattorini, S

    2016-09-01

    One of the purposes of the research program referred to as "systematic biogeography" is the use of species distributions to identify regions and reconstruct biotic area relationships. The reverse, i.e. to group species according to the areas that they live in, leads to the recognition of chorological categories. Biogeographers, working under these two different approaches, have proposed several terms to refer to groups of species that have similar distributions, such as "element", "chorotype" and "component". A historical reconstruction, including semantic observations and philosophical implications, shows that these terms have been used in a variety of senses. The word "component" should not be used in biogeography. The word "element" has been used to identify both a group of species defined according to the biogeographic areas they occupy and a group of species with an assumed shared biogeographic history. It is especially because of the influence of the dispersalist paradigm, which dominated evolutionary thought until the mid-twentieth century, that the second definition has been frequently adopted. The term "element" is therefore ambiguous and its use should always be associated with an explicit definition. The word "chorotype" should be used to define groups of species with similar ranges when no causal assumption is made. The concept of "chorotype," finally, should not be confounded with other concepts such as distributional pattern, cenocron, horofauna, biota, endemic area, area of endemism, biotic element, and generalized track, which are also discussed in this paper.

  16. Polyethylene glycol-coated graphene oxide attenuates antigen-specific IgE production and enhanced antigen-induced T-cell reactivity in ovalbumin-sensitized BALB/c mice

    PubMed Central

    Wu, Hsin-Ying; Lin, Kun-Ju; Wang, Ping-Yen; Lin, Chi-Wen; Yang, Hong-Wei; Ma, Chen-Chi M; Lu, Yu-Jen; Jan, Tong-Rong

    2014-01-01

    Background Graphene oxide (GO) is a promising nanomaterial for potential application in the versatile field of biomedicine. Graphene-based nanomaterials have been reported to modulate the functionality of immune cells in culture and to induce pulmonary inflammation in mice. Evidence pertaining to the interaction between graphene-based nanomaterials and the immune system in vivo remains scarce. The present study investigated the effect of polyethylene glycol-coated GO (PEG-GO) on antigen-specific immunity in vivo. Methods BALB/c mice were intravenously administered with a single dose of PEG-GO (0.5 or 1 mg/kg) 1 hour before ovalbumin (OVA) sensitization, and antigen-specific antibody production and splenocyte reactivity were measured 7 days later. Results Exposure to PEG-GO significantly attenuated the serum level of OVA-specific immunoglobulin E. The production of interferon-γ and interleukin-4 by splenocytes restimulated with OVA in culture was enhanced by treatment with PEG-GO. In addition, PEG-GO augmented the metabolic activity of splenocytes restimulated with OVA but not with the T-cell mitogen concanavalin A. Conclusion Collectively, these results demonstrate that systemic exposure to PEG-GO modulates several aspects of antigen-specific immune responses, including the serum production of immunoglobulin E and T-cell functionality. PMID:25228804

  17. Adaptation of the Endogenous Salmonella enterica Serovar Typhi clyA-Encoded Hemolysin for Antigen Export Enhances the Immunogenicity of Anthrax Protective Antigen Domain 4 Expressed by the Attenuated Live-Vector Vaccine Strain CVD 908-htrA

    PubMed Central

    Galen, James E.; Zhao, Licheng; Chinchilla, Magaly; Wang, Jin Yuan; Pasetti, Marcela F.; Green, Jeffrey; Levine, Myron M.

    2004-01-01

    Bacterial live-vector vaccines aim to deliver foreign antigens to the immune system and induce protective immune responses, and surface-expressed or secreted antigens are generally more immunogenic than cytoplasmic constructs. We hypothesize that an optimum expression system will use an endogenous export system to avoid the need for large amounts of heterologous DNA encoding additional proteins. Here we describe the cryptic chromosomally encoded 34-kDa cytolysin A hemolysin of Salmonella enterica serovar Typhi (ClyA) as a novel export system for the expression of heterologous antigens in the supernatant of attenuated Salmonella serovar Typhi live-vector vaccine strains. We constructed a genetic fusion of ClyA to the reporter green fluorescent protein and showed that in Salmonella serovar Typhi CVD 908-htrA, the fusion protein retains biological activity in both domains and is exported into the supernatant of an exponentially growing live vector in the absence of detectable bacterial lysis. The utility of ClyA for enhancing the immunogenicity of an otherwise problematic antigen was demonstrated by engineering ClyA fused to the domain 4 (D4) moiety of Bacillus anthracis protective antigen (PA). A total of 11 of 15 mice immunized intranasally with Salmonella serovar Typhi exporting the protein fusion manifested fourfold or greater rises in serum anti-PA immunoglobulin G, compared with only 1 of 16 mice immunized with the live vector expressing cytoplasmic D4 (P = 0.0002). In addition, the induction of PA-specific gamma interferon and interleukin 5 responses was observed in splenocytes. This technology offers exceptional versatility for enhancing the immunogenicity of bacterial live-vector vaccines. PMID:15557633

  18. Feature-Based versus Category-Based Induction with Uncertain Categories

    ERIC Educational Resources Information Center

    Griffiths, Oren; Hayes, Brett K.; Newell, Ben R.

    2012-01-01

    Previous research has suggested that when feature inferences have to be made about an instance whose category membership is uncertain, feature-based inductive reasoning is used to the exclusion of category-based induction. These results contrast with the observation that people can and do use category-based induction when category membership is…

  19. RADIO FREQUENCY ATTENUATOR

    DOEpatents

    Giordano, S.

    1963-11-12

    A high peak power level r-f attenuator that is readily and easily insertable along a coaxial cable having an inner conductor and an outer annular conductor without breaking the ends thereof is presented. Spaced first and second flares in the outer conductor face each other with a slidable cylindrical outer conductor portion therebetween. Dielectric means, such as water, contact the cable between the flares to attenuate the radio-frequency energy received thereby. The cylindrical outer conductor portion is slidable to adjust the voltage standing wave ratio to a low level, and one of the flares is slidable to adjust the attenuation level. An integral dielectric container is also provided. (AFC)

  20. Landing gear noise attenuation

    NASA Technical Reports Server (NTRS)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  1. Incremental Bayesian Category Learning From Natural Language.

    PubMed

    Frermann, Lea; Lapata, Mirella

    2016-08-01

    Models of category learning have been extensively studied in cognitive science and primarily tested on perceptual abstractions or artificial stimuli. In this paper, we focus on categories acquired from natural language stimuli, that is, words (e.g., chair is a member of the furniture category). We present a Bayesian model that, unlike previous work, learns both categories and their features in a single process. We model category induction as two interrelated subproblems: (a) the acquisition of features that discriminate among categories, and (b) the grouping of concepts into categories based on those features. Our model learns categories incrementally using particle filters, a sequential Monte Carlo method commonly used for approximate probabilistic inference that sequentially integrates newly observed data and can be viewed as a plausible mechanism for human learning. Experimental results show that our incremental learner obtains meaningful categories which yield a closer fit to behavioral data compared to related models while at the same time acquiring features which characterize the learned categories. (An earlier version of this work was published in Frermann and Lapata .).

  2. Conceptual influences on category-based induction

    PubMed Central

    Gelman, Susan A.; Davidson, Natalie S.

    2013-01-01

    One important function of categories is to permit rich inductive inferences. Prior work shows that children use category labels to guide their inductive inferences. However, there are competing theories to explain this phenomenon, differing in the roles attributed to conceptual information versus perceptual similarity. Seven experiments with 4- to 5-year-old children and adults (N = 344) test these theories by teaching categories for which category membership and perceptual similarity are in conflict, and varying the conceptual basis of the novel categories. Results indicate that for non-natural kind categories that have little conceptual coherence, children make inferences based on perceptual similarity, whereas adults make inferences based on category membership. In contrast, for basic- and ontological-level categories that have a principled conceptual basis, children and adults alike make use of category membership more than perceptual similarity as the basis of their inferences. These findings provide evidence in favor of the role of conceptual information in preschoolers’ inferences, and further demonstrate that labeled categories are not all equivalent; they differ in their inductive potential. PMID:23517863

  3. Procedural-based category learning in patients with Parkinson's disease: impact of category number and category continuity

    PubMed Central

    Filoteo, J. Vincent; Maddox, W. Todd

    2014-01-01

    Previously we found that Parkinson's disease (PD) patients are impaired in procedural-based category learning when category membership is defined by a nonlinear relationship between stimulus dimensions, but these same patients are normal when the rule is defined by a linear relationship (Maddox and Filoteo, 2001; Filoteo et al., 2005a,b). We suggested that PD patients' impairment was due to a deficit in recruiting “striatal units” to represent complex nonlinear rules. In the present study, we further examined the nature of PD patients' procedural-based deficit in two experiments designed to examine the impact of (1) the number of categories, and (2) category discontinuity on learning. Results indicated that PD patients were impaired only under discontinuous category conditions but were normal when the number of categories was increased from two to four. The lack of impairment in the four-category condition suggests normal integrity of striatal medium spiny cells involved in procedural-based category learning. In contrast, and consistent with our previous observation of a nonlinear deficit, the finding that PD patients were impaired in the discontinuous condition suggests that these patients are impaired when they have to associate perceptually distinct exemplars with the same category. Theoretically, this deficit might be related to dysfunctional communication among medium spiny neurons within the striatum, particularly given that these are cholinergic neurons and a cholinergic deficiency could underlie some of PD patients' cognitive impairment. PMID:24600355

  4. Attenuator And Conditioner

    DOEpatents

    Anderson, Gene R.; Armendariz, Marcelino G.; Carson, Richard F.; Bryan, Robert P.; Duckett, III, Edwin B.; Kemme, Shanalyn Adair; McCormick, Frederick B.; Peterson, David W.

    2006-04-04

    An apparatus and method of attenuating and/or conditioning optical energy for an optical transmitter, receiver or transceiver module is disclosed. An apparatus for attenuating the optical output of an optoelectronic connector including: a mounting surface; an array of optoelectronic devices having at least a first end; an array of optical elements having at least a first end; the first end of the array of optical elements optically aligned with the first end of the array of optoelectronic devices; an optical path extending from the first end of the array of optoelectronic devices and ending at a second end of the array of optical elements; and an attenuator in the optical path for attenuating the optical energy emitted from the array of optoelectronic devices. Alternatively, a conditioner may be adapted in the optical path for conditioning the optical energy emitted from the array of optoelectronic devices.

  5. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    SciTech Connect

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  6. On Flat Objects of Finitely Accessible Categories

    PubMed Central

    2013-01-01

    Flat objects of a finitely accessible additive category 𝒞 are described in terms of some objects of the associated functor category of 𝒞, called strongly flat functors. We study closure properties of the class of strongly flat functors, and we use them to deduce the known result that every object of a finitely accessible abelian category has a flat cover. PMID:24292562

  7. Social learning in animals: categories and mechanisms.

    PubMed

    Heyes, C M

    1994-05-01

    There has been relatively little research on the psychological mechanisms of social learning. This may be due, in part, to the practice of distinguishing categories of social learning in relation to ill-defined mechanisms (Davis, 1973; Galef, 1988). This practice both makes it difficult to identify empirically examples of different types of social learning, and gives the false impression that the mechanisms responsible for social learning are clearly understood. It has been proposed that social learning phenomena be subsumed within the categorization scheme currently used by investigators of asocial learning. This scheme distinguishes categories of learning according to observable conditions, namely, the type of experience that gives rise to a change in an animal (single stimulus vs. stimulus-stimulus relationship vs. response-reinforcer relationship), and the type of behaviour in which this change is detected (response evocation vs. learnability) (Rescorla, 1988). Specifically, three alignments have been proposed: (i) stimulus enhancement with single stimulus learning, (ii) observational conditioning with stimulus-stimulus learning, or Pavlovian conditioning, and (iii) observational learning with response-reinforcer learning, or instrumental conditioning. If, as the proposed alignments suggest, the conditions of social and asocial learning are the same, there is some reason to believe that the mechanisms underlying the two sets of phenomena are also the same. This is so if one makes the relatively uncontroversial assumption that phenomena which occur under similar conditions tend to be controlled by similar mechanisms. However, the proposed alignments are intended to be a set of hypotheses, rather than conclusions, about the mechanisms of social learning; as a basis for further research in which animal learning theory is applied to social learning. A concerted attempt to apply animal learning theory to social learning, to find out whether the same mechanisms are

  8. Pattern-induced covert category learning in songbirds

    PubMed Central

    Comins, Jordan A.; Gentner, Timothy Q.

    2015-01-01

    Summary Language is uniquely human, but its acquisition may involve cognitive capacities shared with other species [1-5]. During development, language experience alters speech sound (phoneme) categorization [6-8]. Newborn infants distinguish the phonemes in all languages, but by 10 months show adult-like greater sensitivity to native language phonemic contrasts than non-native contrasts [8, 9]. Distributional theories account for phonetic learning by positing that infants infer category boundaries from modal distributions of speech sounds along acoustic continua [10, 11]. For example, tokens of the sounds /b/ and /p/ cluster around different mean voice onset times. To disambiguate overlapping distributions, contextual theories propose that phonetic category learning is informed by higher-level patterns (e.g. words) in which phonemes normally occur [12-15]. For example, the vowel sounds /I/ and /e/ can occupy similar perceptual spaces, but can be distinguished in the context of “with” and “well”. Both distributional and contextual cues appear to function in speech acquisition [10-12, 16-21]. Non-human species also benefit from distributional cues for category learning [22-24], but whether category learning benefits from contextual information in non-human animals is unknown. The use of higher-level patterns to guide lower-level category learning may reflect uniquely human capacities tied to language acquisition, or more general learning abilities reflecting shared neurobiological mechanisms. Using songbirds, European starlings, we show that higher-level pattern learning covertly enhances categorization of the natural communication sounds. This observation mirrors the support for contextual theories of phonemic category learning in humans, and demonstrates a general form of learning not unique to humans or language. PMID:26119748

  9. Geometric Representation of Association between Categories

    ERIC Educational Resources Information Center

    Heiser, Willem J.

    2004-01-01

    Categories can be counted, rated, or ranked, but they cannot be measured. Likewise, persons or individuals can be counted, rated, or ranked, but they cannot be measured either. Nevertheless, psychology has realized early on that it can take an indirect road to measurement: What can be measured is the strength of association between categories in…

  10. Generalized Categorial Grammar for Unbounded Dependencies Recovery

    ERIC Educational Resources Information Center

    Nguyen, Luan Viet

    2014-01-01

    Accurate recovery of predicate-argument dependencies is vital for interpretation tasks like information extraction and question answering, and unbounded dependencies may account for a significant portion of the dependencies in any given text. This thesis describes a Generalized Categorial Grammar (GCG) which, like other categorial grammars,…

  11. 7 CFR 993.515 - Size categories.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Size categories. 993.515 Section 993.515 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... respective size categories expressed as follows or in an applicable equivalent range expressed in the...

  12. SUSTAIN: A Network Model of Category Learning

    ERIC Educational Resources Information Center

    Love, Bradley C.; Medin, Douglas L.; Gureckis, Todd M.

    2004-01-01

    SUSTAIN (Supervised and Unsupervised STratified Adaptive Incremental Network) is a model of how humans learn categories from examples. SUSTAIN initially assumes a simple category structure. If simple solutions prove inadequate and SUSTAIN is confronted with a surprising event (e.g., it is told that a bat is a mammal instead of a bird), SUSTAIN…

  13. Category-Specificity in Visual Object Recognition

    ERIC Educational Resources Information Center

    Gerlach, Christian

    2009-01-01

    Are all categories of objects recognized in the same manner visually? Evidence from neuropsychology suggests they are not: some brain damaged patients are more impaired in recognizing natural objects than artefacts whereas others show the opposite impairment. Category-effects have also been demonstrated in neurologically intact subjects, but the…

  14. Conceptual Influences on Category-Based Induction

    ERIC Educational Resources Information Center

    Gelman, Susan A.; Davidson, Natalie S.

    2013-01-01

    One important function of categories is to permit rich inductive inferences. Prior work shows that children use category labels to guide their inductive inferences. However, there are competing theories to explain this phenomenon, differing in the roles attributed to conceptual information vs. perceptual similarity. Seven experiments with 4- to…

  15. 46 CFR 120.352 - Battery categories.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Battery categories. 120.352 Section 120.352 Shipping... and Distribution Systems § 120.352 Battery categories. This section applies to batteries installed to... sources of power to final emergency loads. (a) Large. A large battery installation is one connected to...

  16. 46 CFR 183.352 - Battery categories.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Battery categories. 183.352 Section 183.352 Shipping...) ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 183.352 Battery categories. This section applies to batteries installed to meet the requirements of § 183.310 for secondary sources of power...

  17. 46 CFR 120.352 - Battery categories.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Battery categories. 120.352 Section 120.352 Shipping... and Distribution Systems § 120.352 Battery categories. This section applies to batteries installed to... sources of power to final emergency loads. (a) Large. A large battery installation is one connected to...

  18. 46 CFR 129.353 - Battery categories.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Battery categories. 129.353 Section 129.353 Shipping... INSTALLATIONS Power Sources and Distribution Systems § 129.353 Battery categories. This section applies to batteries installed to meet the requirements of § 129.310(a) for secondary sources of power to vital...

  19. 46 CFR 120.352 - Battery categories.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Battery categories. 120.352 Section 120.352 Shipping... and Distribution Systems § 120.352 Battery categories. This section applies to batteries installed to... sources of power to final emergency loads. (a) Large. A large battery installation is one connected to...

  20. 46 CFR 183.352 - Battery categories.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Battery categories. 183.352 Section 183.352 Shipping...) ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 183.352 Battery categories. This section applies to batteries installed to meet the requirements of § 183.310 for secondary sources of power...

  1. 46 CFR 183.352 - Battery categories.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Battery categories. 183.352 Section 183.352 Shipping...) ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 183.352 Battery categories. This section applies to batteries installed to meet the requirements of § 183.310 for secondary sources of power...

  2. 46 CFR 129.353 - Battery categories.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Battery categories. 129.353 Section 129.353 Shipping... INSTALLATIONS Power Sources and Distribution Systems § 129.353 Battery categories. This section applies to batteries installed to meet the requirements of § 129.310(a) for secondary sources of power to vital...

  3. 46 CFR 129.353 - Battery categories.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Battery categories. 129.353 Section 129.353 Shipping... INSTALLATIONS Power Sources and Distribution Systems § 129.353 Battery categories. This section applies to batteries installed to meet the requirements of § 129.310(a) for secondary sources of power to vital...

  4. 46 CFR 129.353 - Battery categories.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Battery categories. 129.353 Section 129.353 Shipping... INSTALLATIONS Power Sources and Distribution Systems § 129.353 Battery categories. This section applies to batteries installed to meet the requirements of § 129.310(a) for secondary sources of power to vital...

  5. 46 CFR 129.353 - Battery categories.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Battery categories. 129.353 Section 129.353 Shipping... INSTALLATIONS Power Sources and Distribution Systems § 129.353 Battery categories. This section applies to batteries installed to meet the requirements of § 129.310(a) for secondary sources of power to vital...

  6. 46 CFR 120.352 - Battery categories.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Battery categories. 120.352 Section 120.352 Shipping... and Distribution Systems § 120.352 Battery categories. This section applies to batteries installed to... sources of power to final emergency loads. (a) Large. A large battery installation is one connected to...

  7. 46 CFR 183.352 - Battery categories.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Battery categories. 183.352 Section 183.352 Shipping...) ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 183.352 Battery categories. This section applies to batteries installed to meet the requirements of § 183.310 for secondary sources of power...

  8. 46 CFR 183.352 - Battery categories.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Battery categories. 183.352 Section 183.352 Shipping...) ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 183.352 Battery categories. This section applies to batteries installed to meet the requirements of § 183.310 for secondary sources of power...

  9. 46 CFR 120.352 - Battery categories.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Battery categories. 120.352 Section 120.352 Shipping... and Distribution Systems § 120.352 Battery categories. This section applies to batteries installed to... sources of power to final emergency loads. (a) Large. A large battery installation is one connected to...

  10. Intra-Myocardial Injection of Both Growth Factors and Heart Derived Sca-1+/CD31− Cells Attenuates Post-MI LV Remodeling More Than Does Cell Transplantation Alone: Neither Intervention Enhances Functionally Significant Cardiomyocyte Regeneration

    PubMed Central

    Wang, Xiaohong; Li, Qinglu; Hu, Qingsong; Suntharalingam, Piradeep; From, Arthur H. L.; Zhang, Jianyi

    2014-01-01

    Insulin-like growth factor 1 (IGF-1) and hepatocyte growth factor (HGF) are two potent cell survival and regenerative factors in response to myocardial injury (MI). We hypothesized that simultaneous delivery of IGF+HGF combined with Sca-1+/CD31− cells would improve the outcome of transplantation therapy in response to the altered hostile microenvironment post MI. One million adenovirus nuclear LacZ-labeled Sca-1+/CD31− cells were injected into the peri-infarction area after left anterior descending coronary artery (LAD) ligation in mice. Recombinant mouse IGF-1+HGF was added to the cell suspension prior to the injection. The left ventricular (LV) function was assessed by echocardiography 4 weeks after the transplantation. The cell engraftment, differentiation and cardiomyocyte regeneration were evaluated by histological analysis. Sca-1+/CD31− cells formed viable grafts and improved LV ejection fraction (EF) (Control, 54.5+/−2.4; MI, 17.6+/−3.1; Cell, 28.2+/−4.2, n = 9, P<0.01). IGF+HGF significantly enhanced the benefits of cell transplantation as evidenced by increased EF (38.8+/−2.2; n = 9, P<0.01) and attenuated adverse structural remodeling. Furthermore, IGF+HGF supplementation increased the cell engraftment rate, promoted the transplanted cell survival, enhanced angiogenesis, and minimally stimulated endogenous cardiomyocyte regeneration in vivo. The in vitro experiments showed that IGF+HGF treatment stimulated Sca-1+/CD31− cell proliferation and inhibited serum free medium induced apoptosis. Supperarray profiling of Sca-1+/CD31− cells revealed that Sca-1+/CD31− cells highly expressed various trophic factor mRNAs and IGF+HGF treatment altered the mRNAs expression patterns of these cells. These data indicate that IGF-1+HGF could serve as an adjuvant to cell transplantation for myocardial repair by stimulating donor cell and endogenous cardiac stem cell survival, regeneration and promoting angiogenesis. PMID:24919180

  11. Can height categories replace weight categories in striking martial arts competitions? A pilot study

    PubMed Central

    Dubnov-Raz, Gal; Mashiach-Arazi, Yael; Nouriel, Ariella; Raz, Raanan; Constantini, Naama W.

    2015-01-01

    In most combat sports and martial arts, athletes compete within weight categories. Disordered eating behaviors and intentional pre-competition rapid weight loss are commonly seen in this population, attributed to weight categorization. We examined if height categories can be used as an alternative to weight categories for competition, in order to protect the health of athletes. Height and weight of 169 child and adolescent competitive karate athletes were measured. Participants were divided into eleven hypothetical weight categories of 5 kg increments, and eleven hypothetical height categories of 5 cm increments. We calculated the coefficient of variation of height and weight by each division method. We also calculated how many participants fit into corresponding categories of both height and weight, and how many would shift a category if divided by height. There was a high correlation between height and weight (r = 0.91, p<0.001). The mean range of heights seen within current weight categories was reduced by 83% when participants were divided by height. When allocating athletes by height categories, 74% of athletes would shift up or down one weight category at most, compared with the current categorization method. We conclude that dividing young karate athletes by height categories significantly reduced the range of heights of competitors within the category. Such categorization would not cause athletes to compete against much heavier opponents in most cases. Using height categories as a means to reduce eating disorders in combat sports should be further examined. PMID:26557193

  12. Can height categories replace weight categories in striking martial arts competitions? A pilot study.

    PubMed

    Dubnov-Raz, Gal; Mashiach-Arazi, Yael; Nouriel, Ariella; Raz, Raanan; Constantini, Naama W

    2015-09-29

    In most combat sports and martial arts, athletes compete within weight categories. Disordered eating behaviors and intentional pre-competition rapid weight loss are commonly seen in this population, attributed to weight categorization. We examined if height categories can be used as an alternative to weight categories for competition, in order to protect the health of athletes. Height and weight of 169 child and adolescent competitive karate athletes were measured. Participants were divided into eleven hypothetical weight categories of 5 kg increments, and eleven hypothetical height categories of 5 cm increments. We calculated the coefficient of variation of height and weight by each division method. We also calculated how many participants fit into corresponding categories of both height and weight, and how many would shift a category if divided by height. There was a high correlation between height and weight (r = 0.91, p<0.001). The mean range of heights seen within current weight categories was reduced by 83% when participants were divided by height. When allocating athletes by height categories, 74% of athletes would shift up or down one weight category at most, compared with the current categorization method. We conclude that dividing young karate athletes by height categories significantly reduced the range of heights of competitors within the category. Such categorization would not cause athletes to compete against much heavier opponents in most cases. Using height categories as a means to reduce eating disorders in combat sports should be further examined.

  13. Conventional Wisdom: Negotiating Conventions of Reference Enhances Category Learning

    ERIC Educational Resources Information Center

    Voiklis, John; Corter, James E.

    2012-01-01

    Collaborators generally coordinate their activities through communication, during which they readily negotiate a shared lexicon for activity-related objects. This social-pragmatic activity both recruits and affects cognitive and social-cognitive processes ranging from selective attention to perspective taking. We ask whether negotiating reference…

  14. Diagnostic Categories in Autobiographical Accounts of Illness.

    PubMed

    Kelly, Michael P

    2015-01-01

    Working within frameworks drawn from the writings of Immanuel Kant, Alfred Schutz, and Kenneth Burke, this article examines the role that diagnostic categories play in autobiographical accounts of illness, with a special focus on chronic disease. Four lay diagnostic categories, each with different connections to formal medical diagnostic categories, serve as typifications to make sense of the way the lifeworld changes over the course of chronic illness. These diagnostic categories are used in conjunction with another set of typifications: lay epidemiologies, lay etiologies, lay prognostics, and lay therapeutics. Together these serve to construct and reconstruct the self at the center of the lifeworld. Embedded within the lay diagnostic categories are narratives of progression, regression, or stability, forms of typification derived from literary and storytelling genres. These narratives are developed by the self in autobiographical accounts of illness.

  15. Seismic attenuation in Florida

    SciTech Connect

    Bellini, J.J.; Bartolini, T.J.; Lord, K.M.; Smith, D.L. . Dept. of Geology)

    1993-03-01

    Seismic signals recorded by the expanded distribution of earthquake seismograph stations throughout Florida and data from a comprehensive review of record archives from stations GAI contribute to an initial seismic attenuation model for the Florida Plateau. Based on calculations of surface particle velocity, a pattern of attenuation exists that appears to deviate from that established for the remainder of the southeastern US. Most values suggest greater seismic attenuation within the Florida Plateau. However, a separate pattern may exist for those signals arising from the Gulf of Mexico. These results have important implications for seismic hazard assessments in Florida and may be indicative of the unique lithospheric identity of the Florida basement as an exotic terrane.

  16. Study preferences for exemplar variability in self-regulated category learning.

    PubMed

    Wahlheim, Christopher N; DeSoto, K Andrew

    2017-02-01

    Increasing exemplar variability during category learning can enhance classification of novel exemplars from studied categories. Four experiments examined whether participants preferred variability when making study choices with the goal of later classifying novel exemplars. In Experiments 1-3, participants were familiarised with exemplars of birds from multiple categories prior to making category-level assessments of learning and subsequent choices about whether to receive more variability or repetitions of exemplars during study. After study, participants classified novel exemplars from studied categories. The majority of participants showed a consistent preference for variability in their study, but choices were not related to category-level assessments of learning. Experiment 4 provided evidence that study preferences were based primarily on theoretical beliefs in that most participants indicated a preference for variability on questionnaires that did not include prior experience with exemplars. Potential directions for theoretical development and applications to education are discussed.

  17. God's Categories: The Effect of Religiosity on Children's Teleological and Essentialist Beliefs about Categories

    ERIC Educational Resources Information Center

    Diesendruck, Gil; Haber, Lital

    2009-01-01

    Creationism implies that God imbued each category with a unique nature and purpose. These implications closely correspond to what some cognitive psychologists define as an essentialistic and teleological stance towards categories. This study assessed to what extent the belief in God as creator of categories is related to the mappings of these…

  18. Tritium Attenuation by Distillation

    SciTech Connect

    Wittman, N.E.

    2001-07-31

    The objective of this study was to determine how a 100 Area distillation system could be used to reduce to a satisfactory low value the tritium content of the dilute moderator produced in the 100 Area stills, and whether such a tritium attenuator would have sufficient capacity to process all this material before it is sent to the 400 Area for reprocessing.

  19. Practitioner perceptions of attenuated psychosis syndrome.

    PubMed

    Jacobs, Elizabeth; Kline, Emily; Schiffman, Jason

    2011-09-01

    The "Attenuated Psychosis Syndrome" (APS, sometimes referred to as the "schizophrenia prodrome") is characterized by subthreshold psychotic-like symptoms and functional decline, and is often associated with significant disability. These symptoms may cause impairment and are of further interest due to their predictive relation to schizophrenia and other psychotic disorders. These symptoms currently are not represented in the diagnostic system for mental health, and it is unclear how they are conceptualized by relevant professionals. The current study surveyed a national sample (n=303) of clinical psychologists, psychiatrists, and general practitioners regarding their clinical appraisal of APS. Practitioners were asked to respond to vignettes representing three conditions: psychosis, subthreshold psychosis (indicating 'attenuated' psychosis symptoms), and no psychotic symptoms. Practitioners' responses suggested that APS is viewed consistently with a DSM-IV-TR defined mental disorder and that most clinicians may diagnose this condition as a full threshold psychotic disorder. Findings tentatively suggest that the inclusion of an attenuated psychosis symptoms category in the forthcoming DSM-5 may be helpful in improving diagnostic reliability and facilitating best practice among community practitioners.

  20. Feature-based versus category-based induction with uncertain categories.

    PubMed

    Griffiths, Oren; Hayes, Brett K; Newell, Ben R

    2012-05-01

    Previous research has suggested that when feature inferences have to be made about an instance whose category membership is uncertain, feature-based inductive reasoning is used to the exclusion of category-based induction. These results contrast with the observation that people can and do use category-based induction when category membership is known. The present experiments examined the conditions that drive feature-based and category-based strategies in induction under category uncertainty. Specifically, 2 experiments investigated whether reliance on feature-based inductive strategies is a product of the lack of coherence in the categories used in previous research or is due to the use of a decision-only induction procedure. Experiment 1 found that feature-based reasoning remained the preferred strategy even when categories with relatively high internal coherence were used. Experiment 2 found a shift toward category-based reasoning when participants were trained to classify category members prior to feature induction. Together, these results suggest that an appropriate conceptual representation must be formed through experience with a category before it is likely to be used as a basis for feature induction.

  1. Searching for Category-Consistent Features: A Computational Approach to Understanding Visual Category Representation.

    PubMed

    Yu, Chen-Ping; Maxfield, Justin T; Zelinsky, Gregory J

    2016-06-01

    This article introduces a generative model of category representation that uses computer vision methods to extract category-consistent features (CCFs) directly from images of category exemplars. The model was trained on 4,800 images of common objects, and CCFs were obtained for 68 categories spanning subordinate, basic, and superordinate levels in a category hierarchy. When participants searched for these same categories, targets cued at the subordinate level were preferentially fixated, but fixated targets were verified faster when they followed a basic-level cue. The subordinate-level advantage in guidance is explained by the number of target-category CCFs, a measure of category specificity that decreases with movement up the category hierarchy. The basic-level advantage in verification is explained by multiplying the number of CCFs by sibling distance, a measure of category distinctiveness. With this model, the visual representations of real-world object categories, each learned from the vast numbers of image exemplars accumulated throughout everyday experience, can finally be studied.

  2. Comparing two K-category assignments by a K-category correlation coefficient.

    PubMed

    Gorodkin, J

    2004-12-01

    Predicted assignments of biological sequences are often evaluated by Matthews correlation coefficient. However, Matthews correlation coefficient applies only to cases where the assignments belong to two categories, and cases with more than two categories are often artificially forced into two categories by considering what belongs and what does not belong to one of the categories, leading to the loss of information. Here, an extended correlation coefficient that applies to K-categories is proposed, and this measure is shown to be highly applicable for evaluating prediction of RNA secondary structure in cases where some predicted pairs go into the category "unknown" due to lack of reliability in predicted pairs or unpaired residues. Hence, predicting base pairs of RNA secondary structure can be a three-category problem. The measure is further shown to be well in agreement with existing performance measures used for ranking protein secondary structure predictions. Server and software is available at http://rk.kvl.dk/.

  3. On Gauging Symmetry of Modular Categories

    NASA Astrophysics Data System (ADS)

    Cui, Shawn X.; Galindo, César; Plavnik, Julia Yael; Wang, Zhenghan

    2016-12-01

    Topological order of a topological phase of matter in two spacial dimensions is encoded by a unitary modular (tensor) category (UMC). A group symmetry of the topological phase induces a group symmetry of its corresponding UMC. Gauging is a well-known theoretical tool to promote a global symmetry to a local gauge symmetry. We give a mathematical formulation of gauging in terms of higher category formalism. Roughly, given a UMC with a symmetry group G, gauging is a 2-step process: first extend the UMC to a G-crossed braided fusion category and then take the equivariantization of the resulting category. Gauging can tell whether or not two enriched topological phases of matter are different, and also provides a way to construct new UMCs out of old ones. We derive a formula for the {H^4}-obstruction, prove some properties of gauging, and carry out gauging for two concrete examples.

  4. Human category learning 2.0.

    PubMed

    Ashby, F Gregory; Maddox, W Todd

    2011-04-01

    During the 1990s and early 2000s, cognitive neuroscience investigations of human category learning focused on the primary goal of showing that humans have multiple category-learning systems and on the secondary goals of identifying key qualitative properties of each system and of roughly mapping out the neural networks that mediate each system. Many researchers now accept the strength of the evidence supporting multiple systems, and as a result, during the past few years, work has begun on the second generation of research questions-that is, on questions that begin with the assumption that humans have multiple category-learning systems. This article reviews much of this second generation of research. Topics covered include (1) How do the various systems interact? (2) Are there different neural systems for categorization and category representation? (3) How does automaticity develop in each system? and (4) Exactly how does each system learn?

  5. NASA Scope and Subject Category Guide

    NASA Technical Reports Server (NTRS)

    2011-01-01

    This guide provides a simple, effective tool to assist aerospace information analysts and database builders in the high-level subject classification of technical materials. Each of the 76 subject categories comprising the classification scheme is presented with a description of category scope, a listing of subtopics, cross references, and an indication of particular areas of NASA interest. The guide also includes an index of nearly 3,000 specific research topics cross referenced to the subject categories. The portable document format (PDF) version of the guide contains links in the index from each input subject to its corresponding categories. In addition to subject classification, the guide can serve as an aid to searching databases that use the classification scheme, and is also an excellent selection guide for those involved in the acquisition of aerospace literature. The CD-ROM contains both HTML and PDF versions.

  6. Words can slow down category learning.

    PubMed

    Brojde, Chandra L; Porter, Chelsea; Colunga, Eliana

    2011-08-01

    Words have been shown to influence many cognitive tasks, including category learning. Most demonstrations of these effects have focused on instances in which words facilitate performance. One possibility is that words augment representations, predicting an across the-board benefit of words during category learning. We propose that words shift attention to dimensions that have been historically predictive in similar contexts. Under this account, there should be cases in which words are detrimental to performance. The results from two experiments show that words impair learning of object categories under some conditions. Experiment 1 shows that words hurt performance when learning to categorize by texture. Experiment 2 shows that words also hurt when learning to categorize by brightness, leading to selectively attending to shape when both shape and hue could be used to correctly categorize stimuli. We suggest that both the positive and negative effects of words have developmental origins in the history of word usage while learning categories. [corrected

  7. Learning, retention, and generalization of haptic categories

    NASA Astrophysics Data System (ADS)

    Do, Phuong T.

    This dissertation explored how haptic concepts are learned, retained, and generalized to the same or different modality. Participants learned to classify objects into three categories either visually or haptically via different training procedures, followed by an immediate or delayed transfer test. Experiment I involved visual versus haptic learning and transfer. Intermodal matching between vision and haptics was investigated in Experiment II. Experiments III and IV examined intersensory conflict in within- and between-category bimodal situations to determine the degree of perceptual dominance between sight and touch. Experiment V explored the intramodal relationship between similarity and categorization in a psychological space, as revealed by MDS analysis of similarity judgments. Major findings were: (1) visual examination resulted in relatively higher performance accuracy than haptic learning; (2) systematic training produced better category learning of haptic concepts across all modality conditions; (3) the category prototypes were rated newer than any transfer stimulus followed learning both immediately and after a week delay; and, (4) although they converged at the apex of two transformational trajectories, the category prototypes became more central to their respective categories and increasingly structured as a function of learning. Implications for theories of multimodal similarity and categorization behavior are discussed in terms of discrimination learning, sensory integration, and dominance relation.

  8. On the flexibility of phonetic categories

    NASA Astrophysics Data System (ADS)

    Francis, Alexander L.; Nusbaum, Howard C.

    2002-05-01

    Research on phonetic category acquisition suggests that over the course of development children shift the relative weight given to various acoustic cues to particular phonetic categories [S. Nittrouer, J. Phon. 20, 1-32 (1992)]. Adults also show flexibility in acquiring second language categories and learning to recognize synthetic speech. In both cases listeners must shift attention among some acoustic cues and change the weighting and mapping of others. Recent research demonstrated that category-level feedback can induce adult listeners to shift attention between conflicting cues to native stop-consonant categories. Subsequent research showed that adult listeners also reorganize the distribution of their attention to acoustic cues in learning to better understand synthetic speech. Moreover, research on learning foreign phonetic contrasts suggests that listeners can learn to direct attention to unfamiliar acoustic cues. These results suggest that phonetic categories are flexible in terms of the nature and quality of the acoustic cues that define them. We argue that this flexibility is a consequence of the basic nature of the general mechanism that mediates speech perception: In order to resolve the problem of context-conditioned variability, listeners must dynamically modify attention to the acoustic signal in a context-dependent manner.

  9. Typicality Mediates Performance during Category Verification in Both Ad-hoc and Well-defined Categories

    PubMed Central

    Sandberg, Chaleece; Sebastian, Rajani; Kiran, Swathi

    2012-01-01

    Background The typicality effect is present in neurologically intact populations for natural, ad-hoc, and well-defined categories. Although sparse, there is evidence of typicality effects in persons with chronic stroke aphasia for natural and ad-hoc categories. However, it is unknown exactly what influences the typicality effect in this population. Aims The present study explores the possible contributors to the typicality effect in persons with aphasia by analyzing and comparing data from both normal and language-disordered populations, from persons with aphasia with more semantic impairment versus those with less semantic impairment, and from two types of categories with very different boundary structure (ad-hoc vs. well-defined). Methods and procedures A total of 40 neurologically healthy adults (20 older, 20 younger) and 35 persons with aphasia (20 LSI (less-semantically impaired) patients, 15 MSI (more-semantically impaired) patients) participated in the study. Participants completed one of two tasks: either category verification for ad-hoc categories or category verification for well-defined categories. Outcomes and Results Neurologically healthy participants showed typicality effects for both ad-hoc and well-defined categories. MSI patients showed a typicality effect for well-defined categories, but not for ad-hoc categories, whereas LSI patients showed a typicality effect for ad-hoc categories, but not for well-defined categories. Conclusions These results suggest that the degree of semantic impairment mediates the typicality effect in persons with aphasia depending on the structure of the category. PMID:22261305

  10. Nutrient attenuation in rivers and streams, Puget Sound Basin, Washington

    USGS Publications Warehouse

    Sheibley, Rich W.; Konrad, Christopher P.; Black, Robert W.

    2015-01-01

    From a management perspective, preservation and improvement of instream nutrient attenuation should focus on increasing the travel time through a reach and contact time of water sediment (reactive) surfaces and lowering nutrient concentrations (and loads) to avoid saturation of instream attenuation and increase attenuation efficiency. These goals can be reached by maintaining and restoring channel-flood plain connectivity, maintaining and restoring healthy riparian zones along streams, managing point and nonpoint nutrient loads to streams and rivers, and restoring channel features that promote attenuation such as the addition of woody debris and maintaining pool-riffle morphologies. Many of these management approaches are already being undertaken during projects aimed to restore quality salmon habitat. Therefore, there is a dual benefit to these projects that also may lead to enhanced potential for nitrogen and phosphorus attenuation.

  11. Control algorithms for dynamic attenuators

    SciTech Connect

    Hsieh, Scott S.; Pelc, Norbert J.

    2014-06-15

    Purpose: The authors describe algorithms to control dynamic attenuators in CT and compare their performance using simulated scans. Dynamic attenuators are prepatient beam shaping filters that modulate the distribution of x-ray fluence incident on the patient on a view-by-view basis. These attenuators can reduce dose while improving key image quality metrics such as peak or mean variance. In each view, the attenuator presents several degrees of freedom which may be individually adjusted. The total number of degrees of freedom across all views is very large, making many optimization techniques impractical. The authors develop a theory for optimally controlling these attenuators. Special attention is paid to a theoretically perfect attenuator which controls the fluence for each ray individually, but the authors also investigate and compare three other, practical attenuator designs which have been previously proposed: the piecewise-linear attenuator, the translating attenuator, and the double wedge attenuator. Methods: The authors pose and solve the optimization problems of minimizing the mean and peak variance subject to a fixed dose limit. For a perfect attenuator and mean variance minimization, this problem can be solved in simple, closed form. For other attenuator designs, the problem can be decomposed into separate problems for each view to greatly reduce the computational complexity. Peak variance minimization can be approximately solved using iterated, weighted mean variance (WMV) minimization. Also, the authors develop heuristics for the perfect and piecewise-linear attenuators which do not requirea priori knowledge of the patient anatomy. The authors compare these control algorithms on different types of dynamic attenuators using simulated raw data from forward projected DICOM files of a thorax and an abdomen. Results: The translating and double wedge attenuators reduce dose by an average of 30% relative to current techniques (bowtie filter with tube current

  12. Neuronal integration in visual cortex elevates face category tuning to conscious face perception.

    PubMed

    Fahrenfort, Johannes J; Snijders, Tineke M; Heinen, Klaartje; van Gaal, Simon; Scholte, H Steven; Lamme, Victor A F

    2012-12-26

    The human brain has the extraordinary capability to transform cluttered sensory input into distinct object representations. For example, it is able to rapidly and seemingly without effort detect object categories in complex natural scenes. Surprisingly, category tuning is not sufficient to achieve conscious recognition of objects. What neural process beyond category extraction might elevate neural representations to the level where objects are consciously perceived? Here we show that visible and invisible faces produce similar category-selective responses in the ventral visual cortex. The pattern of neural activity evoked by visible faces could be used to decode the presence of invisible faces and vice versa. However, only visible faces caused extensive response enhancements and changes in neural oscillatory synchronization, as well as increased functional connectivity between higher and lower visual areas. We conclude that conscious face perception is more tightly linked to neural processes of sustained information integration and binding than to processes accommodating face category tuning.

  13. Multimedia category preferences of working engineers

    NASA Astrophysics Data System (ADS)

    Baukal, Charles E.; Ausburn, Lynna J.

    2016-09-01

    Many have argued for the importance of continuing engineering education (CEE), but relatively few recommendations were found in the literature for how to use multimedia technologies to deliver it most effectively. The study reported here addressed this gap by investigating the multimedia category preferences of working engineers. Four categories of multimedia, with two types in each category, were studied: verbal (text and narration), static graphics (drawing and photograph), dynamic non-interactive graphics (animation and video), and dynamic interactive graphics (simulated virtual reality (VR) and photo-real VR). The results showed that working engineers strongly preferred text over narration and somewhat preferred drawing over photograph, animation over video, and simulated VR over photo-real VR. These results suggest that a variety of multimedia types should be used in the instructional design of CEE content.

  14. Moduli of linear and abelian categories

    NASA Astrophysics Data System (ADS)

    Anel, Mathieu

    2006-07-01

    Linear categories naturally have several identification relations : isomorphisms, categorical equivalences and Morita equivalences. In this thesis, we construct the classifying stacks for these three relations (\\ukcatiso, \\ukcateq, \\ukcatmor) together with the classifying stack of abelian categories (\\ukab), the originality of the subject being that, apart from the first one, these are higher stacks. The principal result is that, under some finiteness assumptions, these stacks are geometric in the sense of C. Simpson. In particular, one recover the Hochschild cohomology of a category C as the tangent complex, i.e. the object classifying first order deformations of C, of these stacks at the point defined by C. Moreover, there exists a natural sequence of surjective morphisms of stacks : \\ukcatiso tto \\ukcateq tto \\ukcatmor tto \\ukab for which we prove that the middle one is etale, and the right one is an equivalence.

  15. Children's internal organization of locative categories.

    PubMed

    Erreich, A; Valian, V

    1979-12-01

    4 locative categories were investigated to determine whether their examples were organized according to the prototype/nonprototype distinction. A ranking task was presented to 30 adult subjects to see whether they would judge those instances which had been designated as prototypes by the experimenter to be the best exemplars of each category. An elicited-drawing task was administered to see whether there was a preference for drawing adult-designated prototypical instances. A matching task was presented to determine whether fewer errors would occur in response to adult-designated prototypical instances. The latter 2 tasks were presented to 4-year-olds, 6-year-olds, and adults, with 17 subjects in each group. The results provide strong evidence of prototype/nonprototype organization in 3 of the locative categories and weak evidence in the fourth. Tentative conclusions regarding the development of such organization are drawn.

  16. Ultrasonic attenuation in pearlitic steel.

    PubMed

    Du, Hualong; Turner, Joseph A

    2014-03-01

    Expressions for the attenuation coefficients of longitudinal and transverse ultrasonic waves are developed for steel with pearlitic microstructure. This type of lamellar duplex microstructure influences attenuation because of the lamellar spacing. In addition, longitudinal attenuation measurements were conducted using an unfocused transducer with 10 MHz central frequency on the cross section of a quenched railroad wheel sample. The dependence of longitudinal attenuation on the pearlite microstructure is observed from the changes of longitudinal attenuation from the quenched tread surface to deeper locations. The results show that the attenuation value is lowest and relatively constant within the quench depth, then increases linearly. The experimental results demonstrate a reasonable agreement with results from the theoretical model. Ultrasonic attenuation provides an important non-destructive method to evaluate duplex microstructure within grains which can be implemented for quality control in conjunction with other manufacturing processes.

  17. Backscatter and attenuation properties of mammalian brain tissues

    NASA Astrophysics Data System (ADS)

    Wijekularatne, Pushpani Vihara

    Traumatic Brain Injury (TBI) is a common category of brain injuries, which contributes to a substantial number of deaths and permanent disability all over the world. Ultrasound technology plays a major role in tissue characterization due to its low cost and portability that could be used to bridge a wide gap in the TBI diagnostic process. This research addresses the ultrasonic properties of mammalian brain tissues focusing on backscatter and attenuation. Orientation dependence and spatial averaging of data were analyzed using the same method resulting from insertion of tissue sample between a transducer and a reference reflector. Apparent backscatter transfer function (ABTF) at 1 to 10 MHz, attenuation coefficient and backscatter coefficient (BSC) at 1 to 5 MHz frequency ranges were measured on ovine brain tissue samples. The resulting ABTF was a monotonically decreasing function of frequency and the attenuation coefficient and BSC generally were increasing functions of frequency, results consistent with other soft tissues such as liver, blood and heart.

  18. Error Discounting in Probabilistic Category Learning

    ERIC Educational Resources Information Center

    Craig, Stewart; Lewandowsky, Stephan; Little, Daniel R.

    2011-01-01

    The assumption in some current theories of probabilistic categorization is that people gradually attenuate their learning in response to unavoidable error. However, existing evidence for this error discounting is sparse and open to alternative interpretations. We report 2 probabilistic-categorization experiments in which we investigated error…

  19. Uncovering Contrast Categories in Categorization with a Probabilistic Threshold Model

    ERIC Educational Resources Information Center

    Verheyen, Steven; De Deyne, Simon; Dry, Matthew J.; Storms, Gert

    2011-01-01

    A contrast category effect on categorization occurs when the decision to apply a category term to an entity not only involves a comparison between the entity and the target category but is also influenced by a comparison of the entity with 1 or more alternative categories from the same domain as the target. Establishing a contrast category effect…

  20. A Probabilistic Account of Exemplar and Category Generation

    ERIC Educational Resources Information Center

    Jern, Alan; Kemp, Charles

    2013-01-01

    People are capable of imagining and generating new category exemplars and categories. This ability has not been addressed by previous models of categorization, most of which focus on classifying category exemplars rather than generating them. We develop a formal account of exemplar and category generation which proposes that category knowledge is…

  1. Category number impacts rule-based and information-integration category learning: a reassessment of evidence for dissociable category-learning systems.

    PubMed

    Stanton, Roger D; Nosofsky, Robert M

    2013-07-01

    Researchers have proposed that an explicit reasoning system is responsible for learning rule-based category structures and that a separate implicit, procedural-learning system is responsible for learning information-integration category structures. As evidence for this multiple-system hypothesis, researchers report a dissociation based on category-number manipulations in which rule-based category learning is worse when the category is composed of 4, rather than 2, response categories; however, information-integration category learning is unaffected by category-number manipulations. We argue that within the reported category-number manipulations, there exists a critical confound: Perceptual clusters used to construct the categories are spread apart in the 4-category condition relative to the 2-category one. The present research shows that when this confound is eliminated, performance on information-integration category learning is worse for 4 categories than for 2 categories, and this finding is demonstrated across 2 different information-integration category structures. Furthermore, model-based analyses indicate that a single-system learning model accounts well for both the original findings and the updated experimental findings reported here.

  2. Derived Categories and Zero-Brane Stability

    SciTech Connect

    Lawrence, Albion

    2001-07-25

    We define a particular class of topological field theories associated to open strings and prove the resulting D-branes and open strings form the bounded derived category of coherent sheaves. This derivation is a variant of some ideas proposed recently by Douglas. We then argue that any 0-brane on any Calabi-Yau threefold must become unstable along some path in the Kahler moduli space. As a byproduct of this analysis we see how the derived category can be invariant under a birational transformation.

  3. Event-related potential parameters of category and property violations during semantic category-based induction.

    PubMed

    Long, Changquan; Lei, Xu; Chen, Jie; Chang, Yun; Chen, Antao; Li, Hong

    2015-06-01

    Previous studies have failed to clarify the event-related potentials (ERPs) that occur in response to categorization and property inferences during category-based induction. The present study examined ERP differences among acceptable-induction conclusions, unrelated-category conclusions, and unrelated-property conclusions to dissociate categorization and property-inference processing during category-based induction. The results showed that: (a) conclusions with categories that were unrelated to the premise evoked greater frontal N2 amplitudes, smaller P3b amplitudes, and greater N400 amplitudes, compared to conclusions with categories that were logically related to the premise; and (b) conclusions with unrelated properties evoked larger late positive components (LPCs) during the 700-800ms time interval compared to conclusions with related properties. These results suggest that the N2-P3b-N400 effects reflect categorization violations, while the LPCs are related to property violations during category-based induction, therefore, the ERP responses to category-related and property-related processes are dissociated respectively during category-based induction.

  4. 75 FR 40756 - Implementation Guidance for Physical Protection of Byproduct Material; Category 1 and Category 2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ...; Federal Register #0; #0; #0;This section of the FEDERAL REGISTER contains notices to the public of #0;the... Regulatory Commission. ACTION: Notice of availability of draft guidance for public comment. SUMMARY: The U. S... requirements for the use and transport of category 1 and category 2 quantities of radioactive material. The...

  5. 75 FR 62694 - Implementation Guidance for Physical Protection of Byproduct Material Category 1 and Category 2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-13

    ... July 14, 2010, the U.S. Nuclear Regulatory Commission (NRC) noticed for public comment implementation guidance for a proposed rule to establish security requirements for the use and transport of Category 1 and Category 2 quantities of radioactive material. The public comment period for this guidance was to...

  6. Category Label Effects on Chinese Children's Inductive Inferences: Modulation by Perceptual Detail and Category Specificity

    ERIC Educational Resources Information Center

    Long, Changquan; Lu, Xiaoying; Zhang, Li; Li, Hong; Deak, Gedeon O.

    2012-01-01

    Inductive generalization of novel properties to same-category or similar-looking objects was studied in Chinese preschool children. The effects of category labels on generalizations were investigated by comparing basic-level labels, superordinate-level labels, and a control phrase applied to three kinds of stimulus materials: colored photographs…

  7. Typicality Mediates Performance during Category Verification in Both Ad-Hoc and Well-Defined Categories

    ERIC Educational Resources Information Center

    Sandberg, Chaleece; Sebastian, Rajani; Kiran, Swathi

    2012-01-01

    Background: The typicality effect is present in neurologically intact populations for natural, ad-hoc, and well-defined categories. Although sparse, there is evidence of typicality effects in persons with chronic stroke aphasia for natural and ad-hoc categories. However, it is unknown exactly what influences the typicality effect in this…

  8. 40 CFR 94.106 - Supplemental test procedures for Category 1 and Category 2 marine engines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... heated by the engine); (ii) Without correction at any ambient water temperature (or equivalent) between 5... commercial Category 1 engines certified using the duty cycle specified in § 94.105(b), the Not to Exceed... Exceed zone which follows: ER29DE99.002 (2) For Category 2 engines certified using the duty...

  9. 10 CFR 37.71 - Additional requirements for transfer of category 1 and category 2 quantities of radioactive...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... category 2 quantities of radioactive material. 37.71 Section 37.71 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL Physical Protection in... radioactive material. A licensee transferring a category 1 or category 2 quantity of radioactive material to...

  10. Attenuated psychosis syndrome: need for debate on a new disorder.

    PubMed

    Carpenter, William T

    2014-01-01

    This 'pro' statement of the controversial issue, defending the need for a new disorder classification of attenuated psychosis syndrome (APS), provides data supporting the clinical validity of this category and responds to the most frequently asserted criticisms. It provides arguments why APS is not pathologizing non-ill behaviors and is not stigmatizing for those affected but rather they merit clinical attention for what is already manifest. It also argues against the view that establishing the diagnostic category of APS results in an unreasoned excessive use of antipsychotic medications but rather encourages prevention and early intervention programs. Finally, bodies of research are presented which could contribute to further validating APS and provide the preconditions for moving this category from Section 3 to Section 2 of DSM-5.1.

  11. Development of Implicit and Explicit Category Learning

    ERIC Educational Resources Information Center

    Huang-Pollock, Cynthia L.; Maddox, W. Todd; Karalunas, Sarah L.

    2011-01-01

    We present two studies that examined developmental differences in the implicit and explicit acquisition of category knowledge. College-attending adults consistently outperformed school-age children on two separate information-integration paradigms due to children's more frequent use of an explicit rule-based strategy. Accuracy rates were also…

  12. 40 CFR 2.105 - Exemption categories.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for Disclosure of Records Under the Freedom of Information Act § 2.105 Exemption categories. (a) The...; (7) Records or information compiled for law enforcement purposes, but only to the extent that the production of such law enforcement records or information: (i) Could reasonably be expected to interfere...

  13. 40 CFR 2.105 - Exemption categories.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... for Disclosure of Records Under the Freedom of Information Act § 2.105 Exemption categories. (a) The...; (7) Records or information compiled for law enforcement purposes, but only to the extent that the production of such law enforcement records or information: (i) Could reasonably be expected to interfere...

  14. Production Determines Category: An Ontology of Art

    ERIC Educational Resources Information Center

    Weh, Michael

    2010-01-01

    It is a mainstream view within the ontology of art that there are singular as well as multiple artworks, but it is also a view that is contested. In this article, the author investigates whether the singular/multiple distinction can be sustained and argues for a new way to determine the category to which an artwork belongs. The author stresses…

  15. Measuring Category Intuitiveness in Unconstrained Categorization Tasks

    ERIC Educational Resources Information Center

    Pothos, Emmanuel M.; Perlman, Amotz; Bailey, Todd M.; Kurtz, Ken; Edwards, Darren J.; Hines, Peter; McDonnell, John V.

    2011-01-01

    What makes a category seem natural or intuitive? In this paper, an unsupervised categorization task was employed to examine observer agreement concerning the categorization of nine different stimulus sets. The stimulus sets were designed to capture different intuitions about classification structure. The main empirical index of category…

  16. Neoliberalism in Two Hong Kong School Categories

    ERIC Educational Resources Information Center

    Woo, David

    2013-01-01

    This article examines the link between the governance of Hong Kong's international school and Direct Subsidy Scheme school categories and changes in the broader Hong Kong society through a neoliberal framework. As Hong Kong's economy has grown since the 1997 handover to the People's Republic of China, an increasing number of people have come to…

  17. Learning about Tool Categories via Eavesdropping

    ERIC Educational Resources Information Center

    Phillips, Brenda; Seston, Rebecca; Kelemen, Deborah

    2012-01-01

    Prior research has found that toddlers will form enduring artifact categories after direct exposure to an adult using a novel tool. Four studies explored whether 2- (N = 48) and 3-year-olds (N = 32) demonstrate this same capacity when learning by eavesdropping. After surreptitiously observing an adult use 1 of 2 artifacts to operate a bell via a…

  18. Family Factors Predicting Categories of Suicide Risk

    ERIC Educational Resources Information Center

    Randell, Brooke P.; Wang, Wen-Ling; Herting, Jerald R.; Eggert, Leona L.

    2006-01-01

    We compared family risk and protective factors among potential high school dropouts with and without suicide-risk behaviors (SRB) and examined the extent to which these factors predict categories of SRB. Subjects were randomly selected from among potential dropouts in 14 high schools. Based upon suicide-risk status, 1,083 potential high school…

  19. Reliability of Multi-Category Rating Scales

    ERIC Educational Resources Information Center

    Parker, Richard I.; Vannest, Kimberly J.; Davis, John L.

    2013-01-01

    The use of multi-category scales is increasing for the monitoring of IEP goals, classroom and school rules, and Behavior Improvement Plans (BIPs). Although they require greater inference than traditional data counting, little is known about the inter-rater reliability of these scales. This simulation study examined the performance of nine…

  20. Categories Influence Predictions about Individual Consistency

    ERIC Educational Resources Information Center

    Rhodes, Marjorie; Gelman, Susan A.

    2008-01-01

    Predicting how people will behave in the future is a critical social-cognitive task. In four studies (N = 150, ages preschool to adult), young children (ages 4-5) used category information to guide their expectations about individual consistency. They predicted that psychological properties (preferences and fears) would remain consistent over time…

  1. Right-of-Way Category Manual.

    ERIC Educational Resources Information Center

    Bowman, James S.; Turmel, Jon P.

    This manual provides information needed to meet the standards for pesticide applicator certification. The thrust of this document is vegetation management in public service rights-of-way such as along utility lines, railroads and highways. Different categories of herbicides are discussed with attention given to how they should be applied, the…

  2. Young Children's Automatic Encoding of Social Categories

    ERIC Educational Resources Information Center

    Weisman, Kara; Johnson, Marissa V.; Shutts, Kristin

    2015-01-01

    The present research investigated young children's automatic encoding of two social categories that are highly relevant to adults: gender and race. Three- to 6-year-old participants learned facts about unfamiliar target children who varied in either gender or race and were asked to remember which facts went with which targets. When participants…

  3. 21 CFR 330.5 - Drug categories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Drug categories. 330.5 Section 330.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE OVER-THE-COUNTER (OTC) HUMAN DRUGS WHICH ARE GENERALLY RECOGNIZED AS SAFE AND EFFECTIVE AND...

  4. 21 CFR 330.5 - Drug categories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Drug categories. 330.5 Section 330.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE OVER-THE-COUNTER (OTC) HUMAN DRUGS WHICH ARE GENERALLY RECOGNIZED AS SAFE AND EFFECTIVE AND...

  5. 21 CFR 330.5 - Drug categories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Drug categories. 330.5 Section 330.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE OVER-THE-COUNTER (OTC) HUMAN DRUGS WHICH ARE GENERALLY RECOGNIZED AS SAFE AND EFFECTIVE AND...

  6. 21 CFR 330.5 - Drug categories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Drug categories. 330.5 Section 330.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE OVER-THE-COUNTER (OTC) HUMAN DRUGS WHICH ARE GENERALLY RECOGNIZED AS SAFE AND EFFECTIVE AND...

  7. 21 CFR 330.5 - Drug categories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Drug categories. 330.5 Section 330.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE OVER-THE-COUNTER (OTC) HUMAN DRUGS WHICH ARE GENERALLY RECOGNIZED AS SAFE AND EFFECTIVE AND...

  8. Multimedia Category Preferences of Working Engineers

    ERIC Educational Resources Information Center

    Baukal, Charles E., Jr.; Ausburn, Lynna J.

    2016-01-01

    Many have argued for the importance of continuing engineering education (CEE), but relatively few recommendations were found in the literature for how to use multimedia technologies to deliver it most effectively. The study reported here addressed this gap by investigating the multimedia category preferences of working engineers. Four categories…

  9. Opposite RHOA functions within the ATLL category.

    PubMed

    Ishikawa, Shumpei

    2016-02-04

    In this issue of Blood, Nagata et al reported that different Ras homolog gene family, member A (RHOA) hotspot mutations among the adult T-cell leukemia/lymphoma (ATLL) category have opposite biochemical activities, which are linked to different T-cell phenotypes.

  10. 40 CFR 2.105 - Exemption categories.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Exemption categories. 2.105 Section 2.105 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL PUBLIC INFORMATION Procedures...; (4) Trade secrets and commercial or financial information obtained from a person and privileged...

  11. The Schetic Categories of the Tlingit Verb.

    ERIC Educational Resources Information Center

    Leer, Jeffry A.

    An analysis of verbs in Tlingit, a U.S. Northwest Coast Indian language, begins with an overview of its situation and usage and of previous research. The second chapter sketches its phonological and syntactic characteristics. Subsequent chapters deal specifically with the verb. An analysis of verb categories distinguishes two groups: argumental…

  12. Learning Phonetic Categories by Tracking Movements

    ERIC Educational Resources Information Center

    Gauthier, Bruno; Shi, Rushen; Xu, Yi

    2007-01-01

    We explore in this study how infants may derive phonetic categories from adult input that are highly variable. Neural networks in the form of self-organizing maps (SOMs; Kohonen, 1989, 1995) were used to simulate unsupervised learning of Mandarin tones. In Simulation 1, we trained the SOMs with syllable-sized continuous F[subscript 0] contours,…

  13. Empire: An Analytical Category for Educational Research

    ERIC Educational Resources Information Center

    Coloma, Roland Sintos

    2013-01-01

    In this article Roland Sintos Coloma argues for the relevance of empire as an analytical category in educational research. He points out the silence in mainstream studies of education on the subject of empire, the various interpretive approaches to deploying empire as an analytic, and the importance of indigeneity in research on empire and…

  14. On Learning Natural-Science Categories That Violate the Family-Resemblance Principle.

    PubMed

    Nosofsky, Robert M; Sanders, Craig A; Gerdom, Alex; Douglas, Bruce J; McDaniel, Mark A

    2017-01-01

    The general view in psychological science is that natural categories obey a coherent, family-resemblance principle. In this investigation, we documented an example of an important exception to this principle: Results of a multidimensional-scaling study of igneous, metamorphic, and sedimentary rocks (Experiment 1) suggested that the structure of these categories is disorganized and dispersed. This finding motivated us to explore what might be the optimal procedures for teaching dispersed categories, a goal that is likely critical to science education in general. Subjects in Experiment 2 learned to classify pictures of rocks into compact or dispersed high-level categories. One group learned the categories through focused high-level training, whereas a second group was required to simultaneously learn classifications at a subtype level. Although high-level training led to enhanced performance when the categories were compact, subtype training was better when the categories were dispersed. We provide an interpretation of the results in terms of an exemplar-memory model of category learning.

  15. 47 CFR 36.142 - Categories and apportionment procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... JURISDICTIONAL SEPARATIONS PROCEDURES; STANDARD PROCEDURES FOR SEPARATING TELECOMMUNICATIONS PROPERTY COSTS...) Other Information Origination/Termination Equipment—Category 1. This category includes the cost of other information origination/termination equipment not assigned to Category 2. The costs of other...

  16. Ultrasonic Attenuation in Zircaloy-4

    SciTech Connect

    Gomez, M.P.; Banchik, A.D.; Lopez Pumarega, M.I.; Ruzzante, J.E.

    2005-04-09

    In this work the relationship between Zircaloy-4 grain size and ultrasonic attenuation behavior was studied for longitudinal waves in the frequency range of 10-90 MHz. The attenuation was analyzed as a function of frequency for samples with different mechanical and heat treatments having recrystallized and Widmanstatten structures with different grain size. The attenuation behavior was analyzed by different scattering models, depending on grain size, wavelength and frequency.

  17. Attenuation of Cavity Bay Noise

    DTIC Science & Technology

    2012-10-01

    amplification, known as peaking. Overall, the palliative devices based on resonant arrays have demonstrated high levels of attenuation which are...when the resonant frequency condition is met. The attenuation from a Helmholtz type resonator is achieved through frictional losses, vortex shedding...3 the λ/4 condition can be fulfilled and therefore porous mesh devices may not be able to provide a high level of attenuation . Resonant arrays

  18. Neural Changes Associated with Nonspeech Auditory Category Learning Parallel Those of Speech Category Acquisition

    PubMed Central

    Liu, Ran; Holt, Lori L.

    2010-01-01

    Native language experience plays a critical role in shaping speech categorization, but the exact mechanisms by which it does so are not well understood. Investigating category learning of nonspeech sounds with which listeners have no prior experience allows their experience to be systematically controlled in a way that is impossible to achieve by studying natural speech acquisition, and it provides a means of probing the boundaries and constraints that general auditory perception and cognition bring to the task of speech category learning. In this study, we used a multimodal, video-game-based implicit learning paradigm to train participants to categorize acoustically complex, nonlinguistic sounds. Mismatch negativity responses to the nonspeech stimuli were collected before and after training to investigate the degree to which neural changes supporting the learning of these nonspeech categories parallel those typically observed for speech category acquisition. Results indicate that changes in mismatch negativity resulting from the nonspeech category learning closely resemble patterns of change typically observed during speech category learning. This suggests that the often-observed “specialized” neural responses to speech sounds may result, at least in part, from the expertise we develop with speech categories through experience rathr than from properties unique to speech (e.g., linguistic or vocal tract gestural information). Furthermore, particular characteristics of the training paradigm may inform our understanding of mechanisms that support natural speech acquisition. PMID:19929331

  19. Treatment of category generation and retrieval in aphasia: Effect of typicality of category items.

    PubMed Central

    Kiran, Swathi; Sandberg, Chaleece; Sebastian, Rajani

    2011-01-01

    Purpose: Kiran and colleagues (Kiran, 2007, 2008; Kiran & Johnson, 2008; Kiran & Thompson, 2003) have previously suggested that training atypical examples within a semantic category is a more efficient treatment approach to facilitating generalization within the category than training typical examples. The present study extended our previous work examining the notion of semantic complexity within goal-derived (ad-hoc) categories in individuals with aphasia. Methods: Six individuals with fluent aphasia (range = 39-84 years) and varying degrees of naming deficits and semantic impairments were involved. Thirty typical and atypical items each from two categories were selected after an extensive stimulus norming task. Generative naming for the two categories was tested during baseline and treatment. Results: As predicted, training atypical examples in the category resulted in generalization to untrained typical examples in five out the five patient-treatment conditions. In contrast, training typical examples (which was in examined three conditions) produced mixed results. One patient showed generalization to untrained atypical examples, whereas two patients did not show generalization to untrained atypical examples. Conclusions: Results of the present study supplement our existing data on the effect of a semantically based treatment for lexical retrieval by manipulating the typicality of category exemplars. PMID:21173393

  20. LINE-ABOVE-GROUND ATTENUATOR

    DOEpatents

    Wilds, R.B.; Ames, J.R.

    1957-09-24

    The line-above-ground attenuator provides a continuously variable microwave attenuator for a coaxial line that is capable of high attenuation and low insertion loss. The device consists of a short section of the line-above- ground plane type transmission lime, a pair of identical rectangular slabs of lossy material like polytron, whose longitudinal axes are parallel to and indentically spaced away from either side of the line, and a geared mechanism to adjust amd maintain this spaced relationship. This device permits optimum fineness and accuracy of attenuator control which heretofore has been difficult to achieve.

  1. Cross-category demand effects of price promotions.

    PubMed

    Leeflang, Peter S H; Parreño-Selva, Josefa

    Do promotions in a certain category lead to higher revenues in other categories? If so, to what degree? The answers to these questions are highly relevant for retailers that supply products in different categories. Empirical findings in studies that consider a limited number of categories indicate small promotional cross-category effects. This study develops a framework to determine the impact of price promotions on category revenues that include interdependencies among a substantial number of categories at the category demand level. The own- and cross-category demand effects are moderated by variables such as promotion intensity, category characteristics (own-category effects), and spatial distances between shelf locations (cross-category effects). The empirical results based on daily store-level scanner data show that approximately half of all price promotions expand own-category revenues, especially for categories with deeper supported discounts. There is a high probability (61%) that a price promotion affects sales of at least one other category. The number of categories affected is not greater than two. Moderate evidence supports the existence of cross-promotional effects between categories more closely located in a store.

  2. Clustering header categories extracted from web tables

    NASA Astrophysics Data System (ADS)

    Nagy, George; Embley, David W.; Krishnamoorthy, Mukkai; Seth, Sharad

    2015-01-01

    Revealing related content among heterogeneous web tables is part of our long term objective of formulating queries over multiple sources of information. Two hundred HTML tables from institutional web sites are segmented and each table cell is classified according to the fundamental indexing property of row and column headers. The categories that correspond to the multi-dimensional data cube view of a table are extracted by factoring the (often multi-row/column) headers. To reveal commonalities between tables from diverse sources, the Jaccard distances between pairs of category headers (and also table titles) are computed. We show how about one third of our heterogeneous collection can be clustered into a dozen groups that exhibit table-title and header similarities that can be exploited for queries.

  3. Security threats categories in healthcare information systems.

    PubMed

    Samy, Ganthan Narayana; Ahmad, Rabiah; Ismail, Zuraini

    2010-09-01

    This article attempts to investigate the various types of threats that exist in healthcare information systems (HIS). A study has been carried out in one of the government-supported hospitals in Malaysia.The hospital has been equipped with a Total Hospital Information System (THIS). The data collected were from three different departments, namely the Information Technology Department (ITD), the Medical Record Department (MRD), and the X-Ray Department, using in-depth structured interviews. The study identified 22 types of threats according to major threat categories based on ISO/IEC 27002 (ISO 27799:2008). The results show that the most critical threat for the THIS is power failure followed by acts of human error or failure and other technological factors. This research holds significant value in terms of providing a complete taxonomy of threat categories in HIS and also an important component in the risk analysis stage.

  4. Health effects of risk-assessment categories

    SciTech Connect

    Kramer, C.F.; Rybicka, K.; Knutson, A.; Morris, S.C.

    1983-10-01

    Environmental and occupational health effects associated with exposures to various chemicals are a subject of increasing concern. One recently developed methodology for assessing the health impacts of various chemical compounds involves the classification of similar chemicals into risk-assessment categories (RACs). This report reviews documented human health effects for a broad range of pollutants, classified by RACs. It complements other studies that have estimated human health effects by RAC based on analysis and extrapolation of data from animal research.

  5. Toward a dual-learning systems model of speech category learning

    PubMed Central

    Chandrasekaran, Bharath; Koslov, Seth R.; Maddox, W. T.

    2014-01-01

    More than two decades of work in vision posits the existence of dual-learning systems of category learning. The reflective system uses working memory to develop and test rules for classifying in an explicit fashion, while the reflexive system operates by implicitly associating perception with actions that lead to reinforcement. Dual-learning systems models hypothesize that in learning natural categories, learners initially use the reflective system and, with practice, transfer control to the reflexive system. The role of reflective and reflexive systems in auditory category learning and more specifically in speech category learning has not been systematically examined. In this article, we describe a neurobiologically constrained dual-learning systems theoretical framework that is currently being developed in speech category learning and review recent applications of this framework. Using behavioral and computational modeling approaches, we provide evidence that speech category learning is predominantly mediated by the reflexive learning system. In one application, we explore the effects of normal aging on non-speech and speech category learning. Prominently, we find a large age-related deficit in speech learning. The computational modeling suggests that older adults are less likely to transition from simple, reflective, unidimensional rules to more complex, reflexive, multi-dimensional rules. In a second application, we summarize a recent study examining auditory category learning in individuals with elevated depressive symptoms. We find a deficit in reflective-optimal and an enhancement in reflexive-optimal auditory category learning. Interestingly, individuals with elevated depressive symptoms also show an advantage in learning speech categories. We end with a brief summary and description of a number of future directions. PMID:25132827

  6. Structural processing and category-specific deficits.

    PubMed

    Marques, J Frederico; Raposo, Ana; Almeida, Jorge

    2013-01-01

    We evaluated the contribution of four structural dimensions (object parts, internal details, objects contours and variability of the representation), as a possible source of categorical processing differences and category-specific deficits. Importantly, these dimensions aggregate 22 different structural measures that have been proposed to describe the Snodgrass and Vanderwart (1980) picture set. Study 1 analysed the differences between the four dimensions across domains and categories. Study 2 investigated how these dimensions may contribute to the performance of two patients with category-specific deficits that have been reported previously in the literature (Farah et al., 1991). The results showed that living things were structurally more complex than non-living things, scoring higher in object parts and object contours. Regarding the variability of the representation, living things did not show much within-item diversity but did show more contour overlap and less visual similarity, the latter two qualities of living things being detrimental to object processing in a naming task. Parts, contours and variability of the representation also differentiated animals, fruits and vegetables and, to a certain degree, non-living things: animals had more parts, fruits had more object contours and non-living things had a lower variability of the representation (which was especially related to higher within-item diversity and lower contour overlap). The same three dimensions predicted patient performance. However, when structural dimensions were considered together with domain (living/non-living) and concept familiarity, only variability of the representation contributed significantly to patient performance.

  7. Improving Causality Induction with Category Learning

    PubMed Central

    Wang, Zhihong; Shao, Zhiqing

    2014-01-01

    Causal relations are of fundamental importance for human perception and reasoning. According to the nature of causality, causality has explicit and implicit forms. In the case of explicit form, causal-effect relations exist at either clausal or discourse levels. The implicit causal-effect relations heavily rely on empirical analysis and evidence accumulation. This paper proposes a comprehensive causality extraction system (CL-CIS) integrated with the means of category-learning. CL-CIS considers cause-effect relations in both explicit and implicit forms and especially practices the relation between category and causality in computation. In elaborately designed experiments, CL-CIS is evaluated together with general causality analysis system (GCAS) and general causality analysis system with learning (GCAS-L), and it testified to its own capability and performance in construction of cause-effect relations. This paper confirms the expectation that the precision and coverage of causality induction can be remarkably improved by means of causal and category learning. PMID:24883419

  8. Metacognitive Control of Categorial Neurobehavioral Decision Systems

    PubMed Central

    Foxall, Gordon R.

    2016-01-01

    The competing neuro-behavioral decision systems (CNDS) model proposes that the degree to which an individual discounts the future is a function of the relative hyperactivity of an impulsive system based on the limbic and paralimbic brain regions and the relative hypoactivity of an executive system based in prefrontal cortex (PFC). The model depicts the relationship between these categorial systems in terms of the antipodal neurophysiological, behavioral, and decision (cognitive) functions that engender normal and addictive responding. However, a case may be made for construing several components of the impulsive and executive systems depicted in the model as categories (elements) of additional systems that are concerned with the metacognitive control of behavior. Hence, this paper proposes a category-based structure for understanding the effects on behavior of CNDS, which includes not only the impulsive and executive systems of the basic model but a superordinate level of reflective or rational decision-making. Following recent developments in the modeling of cognitive control which contrasts Type 1 (rapid, autonomous, parallel) processing with Type 2 (slower, computationally demanding, sequential) processing, the proposed model incorporates an arena in which the potentially conflicting imperatives of impulsive and executive systems are examined and from which a more appropriate behavioral response than impulsive choice emerges. This configuration suggests a forum in which the interaction of picoeconomic interests, which provide a cognitive dimension for CNDS, can be conceptualized. This proposition is examined in light of the resolution of conflict by means of bundling. PMID:26925004

  9. 47 CFR 36.122 - Categories and apportionment procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Central Office Equipment § 36.122 Categories and apportionment procedures. (a) The following categories of central office equipment and apportionment procedures therefore are set forth in §§ 36.123 through 36.126. Operator Systems Equipment Category 1. Tandem Switching Equipment Category 2. Local Switching...

  10. Suicide Risk: Amplifiers and Attenuators.

    ERIC Educational Resources Information Center

    Plutchik, Robert; Van Praag, Herman M.

    1994-01-01

    Attempts to integrate findings on correlates of suicide and violent risk in terms of a theory called a two-stage model of countervailing forces, which assumes that the strength of aggressive impulses is modified by amplifiers and attenuators. The vectorial interaction of amplifiers and attenuators creates an unstable equilibrium making prediction…

  11. Adjustable Optical-Fiber Attenuator

    NASA Technical Reports Server (NTRS)

    Buzzetti, Mike F.

    1994-01-01

    Adjustable fiber-optic attenuator utilizes bending loss to reduce strength of light transmitted along it. Attenuator functions without introducing measurable back-reflection or insertion loss. Relatively insensitive to vibration and changes in temperature. Potential applications include cable television, telephone networks, other signal-distribution networks, and laboratory instrumentation.

  12. Category Number Impacts Rule-Based but Not Information-Integration Category Learning: Further Evidence for Dissociable Category-Learning Systems

    ERIC Educational Resources Information Center

    Maddox, W. Todd; Filoteo, J. Vincent; Hejl, Kelli D.; Ing, A. David

    2004-01-01

    Category number effects on rule-based and information-integration category learning were investigated. Category number affected accuracy and the distribution of best-fitting models in the rule-based task but had no effect on accuracy and little effect on the distribution of best-fining models in the information-integration task. In the 2 category…

  13. P-wave attenuation anisotropy in TI media and its application in fracture parameters inversion

    NASA Astrophysics Data System (ADS)

    He, Yi-Yuan; Hu, Tian-Yue; He, Chuan; Tan, Yu-Yang

    2016-12-01

    The existence of aligned fractures in fluid-saturated rocks leads to obvious attenuation anisotropy and velocity anisotropy. Attenuation anisotropy analysis can be applied to estimate fracture density and scale, which provide important information for reservoir identification. This paper derives P-wave attenuation anisotropy in the ATI media where the symmetry axis is in the arbitrary direction theoretically and modifies the spectral ratio method to measure attenuation anisotropy in the ATI media, thus avoiding a large measurement error when applied to wide azimuth or full azimuth data. Fracture dip and azimuth can be estimated through attenuation anisotropy analysis. For small-scale fractures, fracture scale and fracture density can be determined with enhanced convergence if velocity and attenuation information are both used. We also apply the modified spectralratio method to microseismic field data from an oilfield in East China and extract the fracture dip through attenuation anisotropy analysis. The result agrees with the microseismic monitoring.

  14. 10 CFR 37.21 - Personnel access authorization requirements for category 1 or category 2 quantities of...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... or category 2 quantities of radioactive material. 37.21 Section 37.21 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL Background... 1 or category 2 quantities of radioactive material. (a) General. (1) Each licensee that possesses...

  15. 10 CFR 37.73 - Applicability of physical protection of category 1 and category 2 quantities of radioactive...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... category 2 quantities of radioactive material during transit. 37.73 Section 37.73 Energy NUCLEAR REGULATORY... Protection in Transit § 37.73 Applicability of physical protection of category 1 and category 2 quantities of radioactive material during transit. (a) For shipments of category 1 quantities of radioactive material,...

  16. When is category specific in Alzheimer's disease?

    PubMed

    Laws, Keith R; Gale, Tim M; Leeson, Verity C; Crawford, John R

    2005-08-01

    Mixed findings have emerged concerning whether category-specific disorders occur in Alzheimer's disease. Factors that may contribute to these inconsistencies include: ceiling effects/skewed distributions for control data in some studies; differences in the severity of cognitive deficit in patients; and differences in the type of analysis (in particular, if and how controls are used to analyse single case data). We examined picture naming in Alzheimer's patients and matched elderly healthy normal controls in three experiments. These experiments used stimuli that did and did not produce ceiling effects/skewed data in controls. In Experiment 1, we examined for category effects in individual DAT patients using commonly used analyses for single cases (chi2 and z-scores). The different techniques produced quite different outcomes. In Experiment 2a, we used the same techniques on a different group of patients with similar outcomes. Finally, in Experiment 2b, we examined the same patients but (a) used stimuli that did not produce ceiling effects/skewed distributions in healthy controls, and (b) used statistical methods that did not treat the control sample as a population. We found that ceiling effects in controls may markedly inflate the incidence of dissociations in which living things are differentially impaired and seriously underestimate dissociations in the opposite direction. In addition, methods that treat the control sample as a population led to inflation in the overall number of dissociations detected. These findings have implications for the reliability of category effects previously reported both in Alzheimer patients and in other pathologies. In particular, they suggest that the greater proportion of living than nonliving deficits reported in the literature may be an artifact of the methods used.

  17. The role of mangroves in attenuating storm surges

    USGS Publications Warehouse

    Zhang, Keqi; Liu, Huiqing; Li, Yuepeng; Xu, Hongzhou; Shen, Jian; Rhome, Jamie; Smith, J.

    2012-01-01

    Field observations and numerical simulations indicate that the 6-to-30-km-wide mangrove forest along the Gulf Coast of South Florida effectively attenuated stormsurges from a Category 3 hurricane, Wilma, and protected the inland wetland by reducing an inundation area of 1800 km2 and restricting surge inundation inside the mangrove zone. The surge amplitude decreases at a rate of 40–50 cm/km across the mangrove forest and at a rate of 20 cm/km across the areas with a mixture of mangrove islands with open water. In contrast, the amplitudes of stormsurges at the front of the mangrove zone increase by about 10–30% because of the "blockage" of mangroves to surge water, which can cause greater impacts on structures at the front of mangroves than the case without mangroves. The mangrove forest can also protect the wetlands behind the mangrove zone against surge inundation from a Category 5 hurricane with a fast forward speed of 11.2 m/s (25 mph). However, the forest cannot fully attenuate stormsurges from a Category 5 hurricane with a slow forward speed of 2.2 m/s (5 mph) and reduced surges can still affect the wetlands behind the mangrove zone. The effects of widths of mangrove zones on reducing surge amplitudes are nonlinear with large reduction rates (15–30%) for initial width increments and small rates (<5%) for subsequent width increments.

  18. On a categorial aspect of knowledge representation

    NASA Astrophysics Data System (ADS)

    Tataj, Emanuel; Mulawka, Jan; Nieznański, Edward

    Adequate representation of data is crucial for modeling any type of data. To faithfully present and describe the relevant section of the world it is necessary to select the method that can easily be implemented on a computer system which will help in further description allowing reasoning. The main objective of this contribution is to present methods of knowledge representation using categorial approach. Next to identify the main advantages for computer implementation. Categorical aspect of knowledge representation is considered in semantic networks realisation. Such method borrows already known metaphysics properties for data modeling process. The potential topics of further development of categorical semantic networks implementations are also underlined.

  19. Ambiguity produces attention shifts in category learning.

    PubMed

    Vadillo, Miguel A; Orgaz, Cristina; Luque, David; Nelson, James Byron

    2016-04-01

    It has been suggested that people and nonhuman animals protect their knowledge from interference by shifting attention toward the context when presented with information that contradicts their previous beliefs. Despite that suggestion, no studies have directly measured changes in attention while participants are exposed to an interference treatment. In the present experiments, we adapted a dot-probe task to track participants' attention to cues and contexts while they were completing a simple category learning task. The results support the hypothesis that interference produces a change in the allocation of attention to cues and contexts.

  20. Ambiguity produces attention shifts in category learning

    PubMed Central

    Orgaz, Cristina; Luque, David; Nelson, James Byron

    2016-01-01

    It has been suggested that people and nonhuman animals protect their knowledge from interference by shifting attention toward the context when presented with information that contradicts their previous beliefs. Despite that suggestion, no studies have directly measured changes in attention while participants are exposed to an interference treatment. In the present experiments, we adapted a dot-probe task to track participants’ attention to cues and contexts while they were completing a simple category learning task. The results support the hypothesis that interference produces a change in the allocation of attention to cues and contexts. PMID:26980780

  1. Psychometric properties of the Halstead Category Test.

    PubMed

    Lopez, M N; Charter, R A; Newman, R J

    2000-05-01

    Using the Kuder-Richardson formula 20 (KR-20) corrected for item difficulty, the internal consistency reliability of the Halstead Category Test (HCT) was calculated for a sample (N = 398) of normal patients and volunteers, diffusely brain-damaged patients, and undiagnosed patients sent for neuropsychological assessment. The HCT Total Score reliability was.9716 and the subtest reliabilities ranged from.4587 to.9590. An item analysis found that most of the test items, except for those from Subtests I and II, were within established criteria for item difficulty and the discrimination index.

  2. On Wave-Ice Interaction in the Arctic Marginal Ice Zone: Dispersion, Attenuation, and Ice Response

    DTIC Science & Technology

    2016-06-01

    transfer ) equation: D Dt =� 3 This describes the conservation of wave action (spectral density divided by frequency) where... energy as waves interact with ice. These mechanisms are typically split into two broad categories: 1) conservative (Sice,c) and (2) non-conservative...many individual mechanisms of wave ice interaction and thus, like attenuation, is bulk property. Whereas the mechanisms described above are

  3. On Monoids in the Category of Sets and Relations

    NASA Astrophysics Data System (ADS)

    Jenčová, Anna; Jenča, Gejza

    2017-02-01

    The category R e l is the category of sets (objects) and relations (morphisms). Equipped with the direct product of sets, R e l is a monoidal category. Moreover, R e l is a locally posetal 2-category, since every homset R e l(A,B) is a poset with respect to inclusion. We examine the 2-category of monoids R e l M o n in this category. The morphism we use are lax. This category includes, as subcategories, various interesting classes: hypergroups, partial monoids (which include various types of quantum logics, for example effect algebras) and small categories. We show how the 2-categorical structure gives rise to several previously defined notions in these categories, for example certain types of congruence relations on generalized effect algebras. This explains where these definitions come from.

  4. The Role of Grammatical Category Information in Spoken Word Retrieval

    PubMed Central

    Duràn, Carolina Palma; Pillon, Agnesa

    2011-01-01

    We investigated the role of lexical syntactic information such as grammatical gender and category in spoken word retrieval processes by using a blocking paradigm in picture and written word naming experiments. In Experiments 1, 3, and 4, we found that the naming of target words (nouns) from pictures or written words was faster when these target words were named within a list where only words from the same grammatical category had to be produced (homogeneous category list: all nouns) than when they had to be produced within a list comprising also words from another grammatical category (heterogeneous category list: nouns and verbs). On the other hand, we detected no significant facilitation effect when the target words had to be named within a homogeneous gender list (all masculine nouns) compared to a heterogeneous gender list (both masculine and feminine nouns). In Experiment 2, using the same blocking paradigm by manipulating the semantic category of the items, we found that naming latencies were significantly slower in the semantic category homogeneous in comparison with the semantic category heterogeneous condition. Thus semantic category homogeneity caused an interference, not a facilitation effect like grammatical category homogeneity. Finally, in Experiment 5, nouns in the heterogeneous category condition had to be named just after a verb (category-switching position) or a noun (same-category position). We found a facilitation effect of category homogeneity but no significant effect of position, which showed that the effect of category homogeneity found in Experiments 1, 3, and 4 was not due to a cost of switching between grammatical categories in the heterogeneous grammatical category list. These findings supported the hypothesis that grammatical category information impacts word retrieval processes in speech production, even when words are to be produced in isolation. They are discussed within the context of extant theories of lexical production. PMID

  5. Limits of Generalization between Categories and Implications for Theories of Category Specificity

    PubMed Central

    Bukach, Cindy M.; Phillips, W. Stewart; Gauthier, Isabel

    2010-01-01

    Both domain-specific and expertise accounts of category specialization assume that generalization occurs within a domain but not between domains. Yet it is often difficult to define the boundaries and critical features of object domains. Differences in how categories are defined make it difficult to adjudicate between accounts of category specificity and may lead to contradictory results. For example, evidence for whether car experts recruit the fusiform face area is mixed and this inconsistency may be due to the inclusion of antique cars in one of the studies. The current study tested the generalization of expertise from modern to antique cars and found that modern car experts showed expert discrimination and holistic processing of modern cars, but not antique cars. These findings suggest that the neural specialization underlying perceptual expertise is highly specific and may not generalize to distinct subclasses, even when they share some degree of perceptual and conceptual features. PMID:20952784

  6. Algebraic Theories and (Infinity,1)-Categories

    NASA Astrophysics Data System (ADS)

    Cranch, James

    2010-11-01

    We adapt the classical framework of algebraic theories to work in the setting of (infinity,1)-categories developed by Joyal and Lurie. This gives a suitable approach for describing highly structured objects from homotopy theory. A central example, treated at length, is the theory of E_infinity spaces: this has a tidy combinatorial description in terms of span diagrams of finite sets. We introduce a theory of distributive laws, allowing us to describe objects with two distributing E_infinity stuctures. From this we produce a theory of E_infinity ring spaces. We also study grouplike objects, and produce theories modelling infinite loop spaces (or connective spectra), and infinite loop spaces with coherent multiplicative structure (or connective ring spectra). We use this to construct the units of a grouplike E_infinity ring space in a natural manner. Lastly we provide a speculative pleasant description of the K-theory of monoidal quasicategories and quasicategories with ring-like structures.

  7. The structure and formation of natural categories

    NASA Technical Reports Server (NTRS)

    Fisher, Douglas; Langley, Pat

    1990-01-01

    Categorization and concept formation are critical activities of intelligence. These processes and the conceptual structures that support them raise important issues at the interface of cognitive psychology and artificial intelligence. The work presumes that advances in these and other areas are best facilitated by research methodologies that reward interdisciplinary interaction. In particular, a computational model is described of concept formation and categorization that exploits a rational analysis of basic level effects by Gluck and Corter. Their work provides a clean prescription of human category preferences that is adapted to the task of concept learning. Also, their analysis was extended to account for typicality and fan effects, and speculate on how the concept formation strategies might be extended to other facets of intelligence, such as problem solving.

  8. Category search speeds up face-selective fMRI responses in a non-hierarchical cortical face network.

    PubMed

    Jiang, Fang; Badler, Jeremy B; Righi, Giulia; Rossion, Bruno

    2015-05-01

    The human brain is extremely efficient at detecting faces in complex visual scenes, but the spatio-temporal dynamics of this remarkable ability, and how it is influenced by category-search, remain largely unknown. In the present study, human subjects were shown gradually-emerging images of faces or cars in visual scenes, while neural activity was recorded using functional magnetic resonance imaging (fMRI). Category search was manipulated by the instruction to indicate the presence of either a face or a car, in different blocks, as soon as an exemplar of the target category was detected in the visual scene. The category selectivity of most face-selective areas was enhanced when participants were instructed to report the presence of faces in gradually decreasing noise stimuli. Conversely, the same regions showed much less selectivity when participants were instructed instead to detect cars. When "face" was the target category, the fusiform face area (FFA) showed consistently earlier differentiation of face versus car stimuli than did the "occipital face area" (OFA). When "car" was the target category, only the FFA showed differentiation of face versus car stimuli. These observations provide further challenges for hierarchical models of cortical face processing and show that during gradual revealing of information, selective category-search may decrease the required amount of information, enhancing and speeding up category-selective responses in the human brain.

  9. A functional neuroimaging study of the variables that generate category-specific object processing differences.

    PubMed

    Moore, C J; Price, C J

    1999-05-01

    Brain damage can cause remarkably selective deficits in processing specific categories of objects, indicating the high degree of functional segregation within the brain. The neuroimaging study presented here investigates differences in the neural activity associated with two categories of natural objects (animals and fruit) and two categories of man-made objects (vehicles and tools). Stimuli were outline drawings and the tasks were naming and word-picture matching. For man-made objects, the only category-specific effect was in the left posterior middle temporal cortex, which was most active for drawings of tools, as previously reported. For natural objects, drawings of animals and fruit (relative to drawings of man-made objects) enhanced activity in bilateral anterior temporal and right posterior middle temporal cortices. Critically, these effects with natural objects were not observed when the stimuli were coloured appropriately to facilitate identification. Furthermore, activation in the same right hemisphere areas was also observed for viewing and matching unfamiliar non-objects relative to naming and matching man-made objects. These results indicate that, in the right hemisphere, differences between processing natural relative to man-made objects overlap with the effects of increasing demands on object identification. In the left hemisphere, the effects are more consistent with functional specialization within the semantic system. We discuss (i) how category-specific differences can emerge for multiple reasons and (ii) the implications of these effects on the interpretation of functional imaging data and patients with category-specific deficits.

  10. Attenuation and Velocity tomography can we join them?

    NASA Astrophysics Data System (ADS)

    Debski, Wojciech

    2013-04-01

    Velocity tomography, is now routinely used to image velocity distributions which are subsequently interpreted in terms of the Earth or rock-sample structure. This technique has been successfully used in detailed mapping of the Earth in various scales ranging from the whole globe until very local rock-mass structure, e.g. in mines. It is also used in geo-technical (tunnels, mines, water dams, etc.) and laboratory measurements. The second tomography technique, namely attenuation tomography, is used to image another physical property of rocks: the acoustic attenuation structure usually describe by the parameter Q. This technique is, however, much more difficult than velocity tomography because the attenuation of seismic/acoustic waves is a much more subtle effect than a variation of delays of energy arrival times due to velocity heterogeneities. There exist a lot of factors that can easily disturb attenuation measurements so it is difficult to obtain a reliable image of the attenuation structure. For this reason, a very high quality of data used for attenuation tomography must be ensured. Nevertheless, the additional effort necessary to obtain an image of Q is worthwhile because Q is regarded to be more sensitive to the rock structure than seismic/acoustic wave velocity. Imaging the Q distribution can be achieved by inverting various characteristics of the measured signals: amplitudes, spectra decay, pulse broadening or central frequency shift. The advantages and limitations of each of these approaches are well known. In this presentation we discuss the approach developed for the acoustic ultrasonic tomography imaging and called Enhanced Velocity Tomography and possibility of its using in a ``global seismological'' framework. It consists in a combination of both velocity and attenuation tomography into one scheme to maximize the advantage of the robustness of velocity and the sensitivity to the micro-structure of attenuation.

  11. 14 CFR 29.181 - Dynamic stability: Category A rotorcraft.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Dynamic stability: Category A rotorcraft....181 Dynamic stability: Category A rotorcraft. Any short-period oscillation occurring at any speed from.... Ground and Water Handling Characteristics...

  12. 14 CFR 29.181 - Dynamic stability: Category A rotorcraft.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Dynamic stability: Category A rotorcraft....181 Dynamic stability: Category A rotorcraft. Any short-period oscillation occurring at any speed from.... Ground and Water Handling Characteristics...

  13. 40 CFR 98.310 - Definition of the source category.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Titanium Dioxide Production § 98.310 Definition of the source category. The titanium dioxide production source category consists of facilities that use the chloride process to produce titanium dioxide....

  14. 40 CFR 98.330 - Definition of the source category.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Zinc Production § 98.330 Definition of the source category. The zinc production source category consists of zinc smelters and secondary zinc recycling facilities....

  15. 40 CFR 98.330 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Zinc Production § 98.330 Definition of the source category. The zinc production source category consists of zinc smelters and secondary zinc recycling facilities....

  16. 40 CFR 98.330 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Zinc Production § 98.330 Definition of the source category. The zinc production source category consists of zinc smelters and secondary zinc recycling facilities....

  17. 40 CFR 98.330 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Zinc Production § 98.330 Definition of the source category. The zinc production source category consists of zinc smelters and secondary zinc recycling facilities....

  18. 40 CFR 98.330 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Zinc Production § 98.330 Definition of the source category. The zinc production source category consists of zinc smelters and secondary zinc recycling facilities....

  19. 40 CFR 98.50 - Definition of source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Adipic Acid Production § 98.50 Definition of source category. The adipic acid production source category consists of all adipic acid production facilities that use oxidation to produce adipic acid....

  20. 40 CFR 98.50 - Definition of source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Adipic Acid Production § 98.50 Definition of source category. The adipic acid production source category consists of all adipic acid production facilities that use oxidation to produce adipic acid....

  1. 40 CFR 98.310 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Titanium Dioxide Production § 98.310 Definition of the source category. The titanium dioxide production source category consists of facilities that use the chloride process to produce titanium dioxide....

  2. 40 CFR 98.420 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Carbon Dioxide § 98.420 Definition of the source category. (a) The carbon dioxide (CO2) supplier source category consists of the following: (1)...

  3. 40 CFR 98.420 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Carbon Dioxide § 98.420 Definition of the source category. (a) The carbon dioxide (CO2) supplier source category consists of the following: (1)...

  4. 12 CFR 390.452 - Notice of capital category.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... the FDI Act and this subpart or that the State savings association's capital category has changed...

  5. 12 CFR 208.42 - Notice of capital category.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... member bank shall be deemed to be within a given capital category for purposes of section 38 of the FDI... Board to the bank of its capital category for purposes of section 38 of the FDI Act and this subpart...

  6. 12 CFR 390.452 - Notice of capital category.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... the FDI Act and this subpart or that the State savings association's capital category has changed...

  7. 12 CFR 6.3 - Notice of capital category.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... category for purposes of section 38 of the FDI Act and this part as of the date the national bank or... association of its capital category for purposes of section 38 of the FDI Act and this part or that...

  8. 12 CFR 390.452 - Notice of capital category.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... the FDI Act and this subpart or that the State savings association's capital category has changed...

  9. 12 CFR 208.42 - Notice of capital category.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... member bank shall be deemed to be within a given capital category for purposes of section 38 of the FDI... Board to the bank of its capital category for purposes of section 38 of the FDI Act and this subpart...

  10. 12 CFR 208.42 - Notice of capital category.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... member bank shall be deemed to be within a given capital category for purposes of section 38 of the FDI... Board to the bank of its capital category for purposes of section 38 of the FDI Act and this subpart...

  11. 12 CFR 565.3 - Notice of capital category.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... FDI Act and this part or that the savings association's capital category has changed as provided...

  12. 12 CFR 565.3 - Notice of capital category.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... FDI Act and this part or that the savings association's capital category has changed as provided...

  13. 12 CFR 565.3 - Notice of capital category.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... FDI Act and this part or that the savings association's capital category has changed as provided...

  14. 12 CFR 565.3 - Notice of capital category.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... FDI Act and this part or that the savings association's capital category has changed as provided...

  15. 40 CFR 98.310 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Titanium Dioxide Production § 98.310 Definition of the source category. The titanium dioxide production source category consists of facilities that use the chloride process to produce titanium dioxide....

  16. 40 CFR 98.310 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Titanium Dioxide Production § 98.310 Definition of the source category. The titanium dioxide production source category consists of facilities that use the chloride process to produce titanium dioxide....

  17. 40 CFR 98.310 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Titanium Dioxide Production § 98.310 Definition of the source category. The titanium dioxide production source category consists of facilities that use the chloride process to produce titanium dioxide....

  18. Feature distribution and background knowledge in category learning.

    PubMed

    Murphy, G L; Kaplan, A S

    2000-11-01

    Three experiments examined the interactions of category structure and prior knowledge in category learning. Experiment 1 examined the distribution of atypical or "crossover" features in category learning. In real categories, crossover features may be unevenly distributed--found primarily in very unusual examples of a category (like whales or ostriches). In contrast, in many psychology experiments, each item has exactly one crossover feature. Even versus uneven distribution of crossover features did not affect category learning when the features were neutral. However, when the features were connected by prior knowledge, it was much harder for subjects to learn the structure with the uneven distribution of crossover features. Experiments 2 and 3 found similar results with a slightly less uneven condition. We conclude that learning is a function of the interaction of category structure and prior knowledge rather than either one alone. Furthermore, knowledge benefits learning even when the category contains contradictions of the knowledge, so long as the contradictions are not very salient.

  19. Language, Perceptual Categories and their Interaction: Insights from Computational Modelling

    NASA Astrophysics Data System (ADS)

    Belpaeme, Tony; Bleys, Joris

    How do humans acquire perceptual categories? This question is far from being resolved. Specifically the balance between the influence of nature and nurture on perceptual categories remains the topic of heated debate. We present a computational model and take as case study colour categories to study two issues in perceptual category acquisition. The first issue is the effect of linguistic communication on categories during their acquisition: we demonstrate how categories can become coordinated under the influence of language. The second issue concerns the amount of coordination needed between the categories of individuals in order to achieve unambiguous communication. We show that, depending on how strictly linguistic utterances are interpreted, coordination of the individuals' categories is not always a prerequisite for successful communication.

  20. 40 CFR 98.470 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Injection of Carbon Dioxide § 98.470 Definition of the source category. (a) The injection of carbon dioxide (CO2) source category comprises any well or group of...

  1. 40 CFR 98.470 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Injection of Carbon Dioxide § 98.470 Definition of the source category. (a) The injection of carbon dioxide (CO2) source category comprises any well or group of...

  2. 40 CFR 98.470 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Injection of Carbon Dioxide § 98.470 Definition of the source category. (a) The injection of carbon dioxide (CO2) source category comprises any well or group of...

  3. 40 CFR 98.470 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Injection of Carbon Dioxide § 98.470 Definition of the source category. (a) The injection of carbon dioxide (CO2) source category comprises any well or group of...

  4. 12 CFR 208.42 - Notice of capital category.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... member bank shall be deemed to be within a given capital category for purposes of section 38 of the FDI... Board to the bank of its capital category for purposes of section 38 of the FDI Act and this subpart...

  5. 12 CFR 565.3 - Notice of capital category.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... FDI Act and this part or that the savings association's capital category has changed as provided...

  6. 40 CFR 98.110 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Ferroalloy Production § 98.110 Definition of the source category. The ferroalloy production source category consists of any facility that uses pyrometallurgical..., ferronickel, ferrosilicon, ferrotitanium, ferrotungsten, ferrovanadium, silicomanganese, or silicon metal....

  7. 40 CFR 98.110 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Ferroalloy Production § 98.110 Definition of the source category. The ferroalloy production source category consists of any facility that uses pyrometallurgical..., ferronickel, ferrosilicon, ferrotitanium, ferrotungsten, ferrovanadium, silicomanganese, or silicon metal....

  8. 40 CFR 98.110 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Ferroalloy Production § 98.110 Definition of the source category. The ferroalloy production source category consists of any facility that uses pyrometallurgical..., ferronickel, ferrosilicon, ferrotitanium, ferrotungsten, ferrovanadium, silicomanganese, or silicon metal....

  9. 40 CFR 98.110 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Ferroalloy Production § 98.110 Definition of the source category. The ferroalloy production source category consists of any facility that uses pyrometallurgical..., ferronickel, ferrosilicon, ferrotitanium, ferrotungsten, ferrovanadium, silicomanganese, or silicon metal....

  10. Discontinuous Categories Affect Information-Integration but not Rule-Based Category Learning

    ERIC Educational Resources Information Center

    Maddox, W. Todd; Filoteo, J. Vincent; Lauritzen, J. Scott; Connally, Emily; Hejl, Kelli D.

    2005-01-01

    Three experiments were conducted that provide a direct examination of within-category discontinuity manipulations on the implicit, procedural-based learning and the explicit, hypothesis-testing systems proposed in F. G. Ashby, L. A. Alfonso-Reese, A. U. Turken, and E. M. Waldron's (1998) competition between verbal and implicit systems model.…

  11. Ad Hoc Categories and False Memories: Memory Illusions for Categories Created On-the-Spot.

    PubMed

    Soro, Jerônimo C; Ferreira, Mário B; Semin, Gün R; Mata, André; Carneiro, Paula

    2017-04-06

    Three experiments were designed to test whether experimentally created ad hoc associative networks evoke false memories. We used the DRM (Deese, Roediger, McDermott) paradigm with lists of ad hoc categories composed of exemplars aggregated toward specific goals (e.g., going for a picnic) that do not share any consistent set of features. Experiment 1 revealed considerable levels of false recognitions of critical words from ad hoc categories. False recognitions occurred even when the lists were presented without an organizing theme (i.e., the category's label). Experiments 1 and 2 tested whether (a) the ease of identifying the categories' themes, and (b) the lists' backward associative strength could be driving the effect. List identifiability did not correlate with false recognition, and the effect remained even when backward associative strength was controlled for. Experiment 3 manipulated the distractor items in the recognition task to address the hypothesis that the salience of unrelated items could be facilitating the occurrence of the phenomenon. The effect remained when controlling for this source of facilitation. These results have implications for assumptions made by theories of false memories, namely the preexistence of associations in the activation-monitoring framework and the central role of gist extraction in fuzzy-trace theory, while providing evidence of the occurrence of false memories for more dynamic and context-dependent knowledge structures. (PsycINFO Database Record

  12. Category Formation in Autism: Can Individuals with Autism Form Categories and Prototypes of Dot Patterns?

    ERIC Educational Resources Information Center

    Gastgeb, Holly Zajac; Dundas, Eva M.; Minshew, Nancy J.; Strauss, Mark S.

    2012-01-01

    There is a growing amount of evidence suggesting that individuals with autism have difficulty with categorization. One basic cognitive ability that may underlie this difficulty is the ability to abstract a prototype. The current study examined prototype and category formation with dot patterns in high-functioning adults with autism and matched…

  13. Category Specificity in Normal Episodic Learning: Applications to Object Recognition and Category-Specific Agnosia

    ERIC Educational Resources Information Center

    Bukach, Cindy M.; Bub, Daniel N.; Masson, Michael E. J.; Lindsay, D. Stephen

    2004-01-01

    Studies of patients with category-specific agnosia (CSA) have given rise to multiple theories of object recognition, most of which assume the existence of a stable, abstract semantic memory system. We applied an episodic view of memory to questions raised by CSA in a series of studies examining normal observers' recall of newly learned attributes…

  14. Category Labels Induce Boundary-Dependent Perceptual Warping in Learned Speech Categories

    ERIC Educational Resources Information Center

    Swan, Kristen; Myers, Emily

    2013-01-01

    Adults tend to perceive speech sounds from their native language as members of distinct and stable categories; however, they fail to perceive differences between many non-native speech sounds without a great deal of training. The present study investigates the effects of categorization training on adults' ability to discriminate non-native…

  15. Case-like Categories in Children: The Actor and Some Related Categories

    ERIC Educational Resources Information Center

    Braine, Martin D. S.; Wells, Robin S.

    1978-01-01

    Five experiments were performed in which nursery school children were taught to identify persons, animals, or objects in pictures that took the nominative, objective, or locative case in sentences about the pictures. Inferences are made about categories in children's thinking including animate, and actor and agent. (CTM)

  16. 40 CFR 1042.310 - Engine selection for Category 1 and Category 2 engines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENGINES AND VESSELS Testing Production-line Engines § 1042.310 Engine selection for Category 1 and... subject to production-line testing. (c) For each engine that fails to meet emission standards, test two... sample size is one engine or one percent of the projected U.S.-directed production volume for all...

  17. 40 CFR 1042.310 - Engine selection for Category 1 and Category 2 engines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ENGINES AND VESSELS Testing Production-line Engines § 1042.310 Engine selection for Category 1 and... subject to production-line testing. (c) For each engine that fails to meet emission standards, test two... sample size is one engine or one percent of the projected U.S.-directed production volume for all...

  18. 40 CFR 1042.310 - Engine selection for Category 1 and Category 2 engines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ENGINES AND VESSELS Testing Production-line Engines § 1042.310 Engine selection for Category 1 and... subject to production-line testing. (c) For each engine that fails to meet emission standards, test two... sample size is one engine or one percent of the projected U.S.-directed production volume for all...

  19. 40 CFR 1042.310 - Engine selection for Category 1 and Category 2 engines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ENGINES AND VESSELS Testing Production-line Engines § 1042.310 Engine selection for Category 1 and... subject to production-line testing. (c) For each engine that fails to meet emission standards, test two... sample size is one engine or one percent of the projected U.S.-directed production volume for all...

  20. The Conceptual Grouping Effect: Categories Matter (and Named Categories Matter More)

    ERIC Educational Resources Information Center

    Lupyan, Gary

    2008-01-01

    Do conceptual categories affect basic visual processing? A conceptual grouping effect for familiar stimuli is reported using a visual search paradigm. Search through conceptually-homogeneous non-targets was faster and more efficient than search through conceptually-heterogeneous non-targets. This effect cannot be attributed to perceptual factors…

  1. Developing a map of geologically defined site-condition categories for California

    USGS Publications Warehouse

    Wills, C.J.; Clahan, K.B.

    2006-01-01

    Consideration of site conditions is a vital step in analyzing and predicting earthquake ground motion. The importance of amplification by soil conditions has long been recognized, but though many seismic-instrument sites have been characterized by their geologic conditions, there has been no consistent, simple classification applied to all sites. As classification of sites by shear-wave velocity has become more common, the need to go back and provide a simple uniform classification for all stations has become apparent. Within the Pacific Earthquake Engineering Research Center's Next Generation Attenuation equation project, developers of attenuation equations recognized the need to consider site conditions and asked that the California Geological Survey provide site conditions information for all stations that have recorded earthquake ground motion in California. To provide these estimates, we sorted the available shear-wave velocity data by geologic unit, generalized the geologic units, and prepared a map so that we could use the extent of the map units to transfer the velocity characteristics from the sites where they were measured to sites on the same or similar materials. This new map is different from the California Geological Survey "preliminary site-conditions map of California" in that 19 geologically defined categories are used, rather than National Earthquake Hazards Reduction Program categories. Although this map does not yet cover all of California, when completed it may provide a basis for more precise consideration of site conditions in ground-motion calculations.

  2. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    NASA Technical Reports Server (NTRS)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  3. Relationship between Jovian Hectometric Attenuation Lanes And Io Volcanic Activity

    NASA Technical Reports Server (NTRS)

    Menietti, J. D.; Gurnett, D. A.; Spencer, J. R.; Stansberry, J. A.

    2001-01-01

    Within the Galileo plasma wave instrument data a narrow (in frequency) attenuation band is seen in the hectometric (HOM) emission that varies in frequency with system III longitude. This attenuation lane is believed to be the result of near-grazing incidence or coherent scattering of radio emission near the outer edge of the Io torus, i.e., when the ray path is nearly tangent to an L shell containing the Io flux tube. Such a process should, therefore, be enhanced when the Io volcanic activity is increased and the Io flux tube has enhanced density. We have performed a systematic study of the existing Galileo radio emission data in an effort to determine the phenomenology and frequency of occurrence of the attenuation lanes and the association, if any, with published volcanic activity of Io. Our results indicate that the attenuation lanes are present almost all of the time but are enhanced on occasion. The best examples of attenuation lanes occur when Galileo is within approximately 65 R(sub J) of Jupiter and thus are probably more apparent because of the increased signal-to-noise ratio of the radio receivers. The lack of continuous monitoring of Io activity and the lack of known activity on the anti-Earthward side of Io are problematic and make detailed correlation with radio emission very difficult at this time. Nevertheless, if the data are displayed for periods when the spacecraft is within 65 R(sub J) (i.e., for each perijove pass), then the highest-contrast lanes occur on most passes when the Io volcanic activity is also high for that pass. These results support our current understanding of attenuation lane formation and suggest that future efforts can be made to better understand the interaction of HOM emission with the Io flux tube.

  4. Memory Errors Reveal a Bias to Spontaneously Generalize to Categories

    ERIC Educational Resources Information Center

    Sutherland, Shelbie L.; Cimpian, Andrei; Leslie, Sarah-Jane; Gelman, Susan A.

    2015-01-01

    Much evidence suggests that, from a young age, humans are able to generalize information learned about a subset of a category to the category itself. Here, we propose that--beyond simply being able to perform such generalizations--people are "biased" to generalize to categories, such that they routinely make spontaneous, implicit…

  5. When More Is Less: Feedback Effects in Perceptual Category Learning

    ERIC Educational Resources Information Center

    Maddox, W. Todd; Love, Bradley C.; Glass, Brian D.; Filoteo, J. Vincent

    2008-01-01

    Rule-based and information-integration category learning were compared under minimal and full feedback conditions. Rule-based category structures are those for which the optimal rule is verbalizable. Information-integration category structures are those for which the optimal rule is not verbalizable. With minimal feedback subjects are told whether…

  6. 40 CFR 98.420 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Carbon Dioxide § 98.420 Definition of the source category. (a) The carbon dioxide (CO2) supplier source category consists of the following: (1) Facilities...) This source category is focused on upstream supply. It does not cover: (1) Storage of CO2 above...

  7. 32 CFR 728.113 - Categories of pay patients.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Categories of pay patients. 728.113 Section 728.113 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL MEDICAL AND... Pay Patients § 728.113 Categories of pay patients. The categories of patients for whom...

  8. 14 CFR 61.159 - Aeronautical experience: Airplane category rating.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aeronautical experience: Airplane category... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a...

  9. About Categories of Tense and Aspect in Indonesian/Malay.

    ERIC Educational Resources Information Center

    Alieva, Natalia F.

    This paper examines whether there is a grammatical category of tense in the Indonesian/Malay language (IML), suggesting that IML has a syntactical category of tense that serves to grammaticize time relations in a clause predicate which is not necessarily verbal. The discussion takes a systemic view of grammatical categories in an analytical…

  10. Empirical Investigation of Counselor Self-Talk Categories.

    ERIC Educational Resources Information Center

    Morran, D. Keith; And Others

    1989-01-01

    Identified categories of counselor self-talk and explored possible dimensions underlying categories. Counselors (N=38) conducted interviews with female client and then completed stimulated-recall, thought-listing exercise. Trained judges categorized resulting 768 self-talk statements into 14 categories with 4 largest being client-focused…

  11. 40 CFR 98.160 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Hydrogen Production § 98.160 Definition of the source category. (a) A hydrogen production source category consists of facilities that produce hydrogen gas sold as a product to other entities. (b) This source category comprises process units that produce hydrogen...

  12. 40 CFR 98.160 - Definition of the source category.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Hydrogen Production § 98.160 Definition of the source category. (a) A hydrogen production source category consists of facilities that produce hydrogen gas sold as a product to other entities. (b) This source category comprises process units that produce hydrogen...

  13. 40 CFR 98.160 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Hydrogen Production § 98.160 Definition of the source category. (a) A hydrogen production source category consists of facilities that produce hydrogen gas sold as a product to other entities. (b) This source category comprises process units that produce hydrogen...

  14. 40 CFR 98.160 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Hydrogen Production § 98.160 Definition of the source category. (a) A hydrogen production source category consists of facilities that produce hydrogen gas sold as a product to other entities. (b) This source category comprises process units that produce hydrogen...

  15. 40 CFR 98.160 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Hydrogen Production § 98.160 Definition of the source category. (a) A hydrogen production source category consists of facilities that produce hydrogen gas sold as a product to other entities. (b) This source category comprises process units that produce hydrogen...

  16. Eyetracking Reveals Multiple-Category Use in Induction

    ERIC Educational Resources Information Center

    Chen, Stephanie Y.; Ross, Brian H.; Murphy, Gregory L.

    2016-01-01

    Category information is used to predict properties of new category members. When categorization is uncertain, people often rely on only one, most likely category to make predictions. Yet studies of perception and action often conclude that people combine multiple sources of information near-optimally. We present a perception-action analog of…

  17. Effect of Within-Category Spacing on Free Recall

    ERIC Educational Resources Information Center

    Borges, Marilyn A.; Mandler, George

    1972-01-01

    Contrary to previous experiments which found recall with blocked spacing always superior to recall with random" spacings, these experiments found that total recall was a function of two independent factors: (a) category representation, and (b) items per category represented (IPC). Both factors are dependent upon within-category spacing.…

  18. Cross-Classification and Category Representation in Children's Concepts

    ERIC Educational Resources Information Center

    Nguyen, Simone P.

    2007-01-01

    Items commonly belong to many categories. Cross-classification is the classification of a single item into more than one category. This research explored 2- to 6-year-old children's use of 2 different category systems for cross-classification: script (e.g., school-time items, birthday party items) and taxonomic (e.g., animals, clothes). The…

  19. 47 CFR 36.142 - Categories and apportionment procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Equipment to the jurisdictions shall be updated annually. Cable and Wire Facilities ... Information Origination/termination (iot) Equipment § 36.142 Categories and apportionment procedures. (a) Other Information Origination/Termination Equipment—Category 1. This category includes the cost of...

  20. 47 CFR 36.126 - Circuit equipment-Category 4.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Equipment Excluding Wideband—Category 4.13—The cost of Circuit Equipment associated with exchange line plant... wire facilities described in § 36.156. (3) All Other Interexchange Circuit Equipment—Category 4.23—This... facilities as described in § 36.152(c). (i) The category 4.3 cost of host/remote circuit equipment...

  1. 30 CFR 57.22003 - Mine category or subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standards for Methane in Metal and Nonmetal Mines Mine Categorization § 57.22003 Mine category or... methane and dusts containing volatile matter. Categories and subcategories are defined as follows: (1) Category I applies to mines that operate within a combustible ore body and either liberate methane or...

  2. 40 CFR 98.440 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Geologic Sequestration of Carbon Dioxide § 98.440 Definition of the source category. (a) The geologic sequestration of carbon dioxide (CO2) source category... Underground Injection Control program. (c) This source category does not include a well or group of...

  3. 40 CFR 98.440 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Geologic Sequestration of Carbon Dioxide § 98.440 Definition of the source category. (a) The geologic sequestration of carbon dioxide (CO2) source category... Underground Injection Control program. (c) This source category does not include a well or group of...

  4. The Development of Category Learning Strategies: What Makes the Difference?

    ERIC Educational Resources Information Center

    Hammer, Rubi; Diesendruck, Gil; Weinshall, Daphna; Hochstein, Shaul

    2009-01-01

    Category learning can be achieved by identifying common features among category members, distinctive features among non-members, or both. These processes are psychologically and computationally distinct, and may have implications for the acquisition of categories at different hierarchical levels. The present study examines an account of children's…

  5. 40 CFR 98.360 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... systems for cattle and swine, manure composting, and aerobic treatment. (c) This source category does not... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Manure Management § 98.360 Definition of the source category. (a) This source category consists of livestock facilities with manure management systems that emit...

  6. 36 CFR 292.22 - Land category assignments.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Land category assignments... NATIONAL RECREATION AREAS Hells Canyon National Recreation Area-Private Lands § 292.22 Land category assignments. (a) Land categories. (1) All privately owned lands within the HCNRA are to be assigned to one...

  7. The Linguistic Construction of Social Categories in Toddlers

    ERIC Educational Resources Information Center

    Diesendruck, Gil; Deblinger-Tangi, Ronit

    2014-01-01

    Kindergarteners treat certain social categories as natural kinds. This study addressed how children pick out social categories. Ninety-one 19-and 26-month-olds were familiarized to exemplars of categories of people (e.g., Blacks-Whites, men-women) and animals (e.g., cows-horses). Participants then saw a picture matching the familiarization…

  8. 14 CFR 91.325 - Primary category aircraft: Operating limitations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Primary category aircraft: Operating... Flight Operations § 91.325 Primary category aircraft: Operating limitations. (a) No person may operate a primary category aircraft carrying persons or property for compensation or hire. (b) No person may...

  9. 14 CFR 91.325 - Primary category aircraft: Operating limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Primary category aircraft: Operating... Flight Operations § 91.325 Primary category aircraft: Operating limitations. (a) No person may operate a primary category aircraft carrying persons or property for compensation or hire. (b) No person may...

  10. On Classification of Modular Categories by Rank: Table A.1

    SciTech Connect

    Bruillard, Paul; Ng, Siu-Hung; Rowell, Eric C.; Wang, Zhenghan

    2016-04-10

    The feasibility of a classification-by-rank program for modular categories follows from the Rank-Finiteness Theorem. We develop arithmetic, representation theoretic and algebraic methods for classifying modular categories by rank. As an application, we determine all possible fusion rules for all rank=5 modular categories and describe the corresponding monoidal equivalence classes.

  11. Attenuation of the DNA Damage Response by Transforming Growth Factor-Beta Inhibitors Enhances Radiation Sensitivity of Non–Small-Cell Lung Cancer Cells In Vitro and In Vivo

    SciTech Connect

    Du, Shisuo; Bouquet, Sophie; Lo, Chen-Hao; Pellicciotta, Ilenia; Bolourchi, Shiva; Parry, Renate; Barcellos-Hoff, Mary Helen

    2015-01-01

    Purpose: To determine whether transforming growth factor (TGF)-β inhibition increases the response to radiation therapy in human and mouse non–small-cell lung carcinoma (NSCLC) cells in vitro and in vivo. Methods and Materials: TGF-β–mediated growth response and pathway activation were examined in human NSCLC NCI-H1299, NCI-H292, and A549 cell lines and murine Lewis lung cancer (LLC) cells. Cells were treated in vitro with LY364947, a small-molecule inhibitor of the TGF-β type 1 receptor kinase, or with the pan-isoform TGF-β neutralizing monoclonal antibody 1D11 before radiation exposure. The DNA damage response was assessed by ataxia telangiectasia mutated (ATM) or Trp53 protein phosphorylation, γH2AX foci formation, or comet assay in irradiated cells. Radiation sensitivity was determined by clonogenic assay. Mice bearing syngeneic subcutaneous LLC tumors were treated with 5 fractions of 6 Gy and/or neutralizing or control antibody. Results: The NCI-H1299, A549, and LLC NSCLC cell lines pretreated with LY364947 before radiation exposure exhibited compromised DNA damage response, indicated by decreased ATM and p53 phosphorylation, reduced γH2AX foci, and increased radiosensitivity. The NCI-H292 cells were unresponsive. Transforming growth factor-β signaling inhibition in irradiated LLC cells resulted in unresolved DNA damage. Subcutaneous LLC tumors in mice treated with TGF-β neutralizing antibody exhibited fewer γH2AX foci after irradiation and significantly greater tumor growth delay in combination with fractionated radiation. Conclusions: Inhibition of TGF-β before radiation attenuated DNA damage recognition and increased radiosensitivity in most NSCLC cells in vitro and promoted radiation-induced tumor control in vivo. These data support the rationale for concurrent TGF-β inhibition and RT to provide therapeutic benefit in NSCLC.

  12. Combination therapy with andrographolide and d-penicillamine enhanced therapeutic advantage over monotherapy with d-penicillamine in attenuating fibrogenic response and cell death in the periportal zone of liver in rats during copper toxicosis.

    PubMed

    Roy, Dijendra Nath; Sen, Gargi; Chowdhury, Kaustav Dutta; Biswas, Tuli

    2011-01-01

    Long treatment regime with d-penicillamine is needed before it can exert clinically meaningful benefits in the treatment of copper toxicosis. The consequence of long-term d-penicillamine treatment is associated with numerous side effects. The limitations of d-penicillamine monotherapy prompted us to search for more effective treatment strategies that could decrease the duration of d-penicillamine therapy. The present study was designed to evaluate the therapeutic potential of d-penicillamine in combination with another hepatoprotective drug, andrographolide in treatment of copper toxicosis in rats. d-penicillamine treatment led to the excretion of copper through urine. Addition of andrographolide to d-penicillamine regime appeared to increase protection of liver by increasing the biliary excretion of copper and reduction in cholestatic injury. The early removal of the causative agent copper during combination treatment was the most effective therapeutic intervention that contributed to the early rectification of fibrosis in liver. Combination treatment reduced Kupffer cells accumulation and TNFα production in liver of copper exposed rats. In particular, andrographolide mediated the anti-inflammatory effect by inhibiting the cytokine production. However, another possible mechanism of cytoprotection of andrographolide was decreasing mitochondrial production of superoxide anions that resulted in better restoration of mitochondrial dysfunction during combination therapy than monotherapy. Furthermore, ROS inhibition by combination regimen resulted in significant decline in activation of caspase cascade. Inhibition of caspases attenuated apoptosis of hepatocytes, induced by chronic copper exposure. In summary, this study suggested that added benefit of combination treatment over use of either agent alone in alleviating the hepatotoxicity and fibrosis associated with copper toxicosis.

  13. Combination therapy with andrographolide and D-penicillamine enhanced therapeutic advantage over monotherapy with D-penicillamine in attenuating fibrogenic response and cell death in the periportal zone of liver in rats during copper toxicosis

    SciTech Connect

    Roy, Dijendra Nath; Sen, Gargi; Chowdhury, Kaustav Dutta; Biswas, Tuli

    2011-01-01

    Long treatment regime with D-penicillamine is needed before it can exert clinically meaningful benefits in the treatment of copper toxicosis. The consequence of long-term D-penicillamine treatment is associated with numerous side effects. The limitations of D-penicillamine monotherapy prompted us to search for more effective treatment strategies that could decrease the duration of D-penicillamine therapy. The present study was designed to evaluate the therapeutic potential of D-penicillamine in combination with another hepatoprotective drug, andrographolide in treatment of copper toxicosis in rats. D-penicillamine treatment led to the excretion of copper through urine. Addition of andrographolide to D-penicillamine regime appeared to increase protection of liver by increasing the biliary excretion of copper and reduction in cholestatic injury. The early removal of the causative agent copper during combination treatment was the most effective therapeutic intervention that contributed to the early rectification of fibrosis in liver. Combination treatment reduced Kupffer cells accumulation and TNF{alpha} production in liver of copper exposed rats. In particular, andrographolide mediated the anti-inflammatory effect by inhibiting the cytokine production. However, another possible mechanism of cytoprotection of andrographolide was decreasing mitochondrial production of superoxide anions that resulted in better restoration of mitochondrial dysfunction during combination therapy than monotherapy. Furthermore, ROS inhibition by combination regimen resulted in significant decline in activation of caspase cascade. Inhibition of caspases attenuated apoptosis of hepatocytes, induced by chronic copper exposure. In summary, this study suggested that added benefit of combination treatment over use of either agent alone in alleviating the hepatotoxicity and fibrosis associated with copper toxicosis.

  14. The peptide growth factor, phytosulfokine, attenuates pattern-triggered immunity.

    PubMed

    Igarashi, Daisuke; Tsuda, Kenichi; Katagiri, Fumiaki

    2012-07-01

    Pattern-triggered immunity (PTI) is triggered by recognition of elicitors called microbe-associated molecular patterns (MAMPs). Although immune responses may provide good protection of plants from pathogen attack, excessive immune responses have negative impacts on plant growth and development. Thus, a good balance between positive and negative effects on the immune signaling network is important for plant fitness. However, little information is known about the molecular mechanisms that are involved in attenuation of PTI. Here, we describe a growth-promoting peptide hormone, phytosulfokine (PSK), as attenuating PTI signaling in Arabidopsis. This research was motivated by the observation that expression of the PSK Receptor 1 (PSKR1) gene was induced by MAMP treatment. Plants homozygous for pskr1 T-DNA insertions showed enhanced defense gene expression and seedling growth inhibition triggered by MAMPs. The pskr1 plants also showed enhanced PTI against the bacterial pathogen Pseudomonas syringae. These results indicate that the PSKR-mediated signaling attenuates immune responses. Tyrosyl protein sulfotransferase (TPST) is an enzyme required for production of the mature sulfated PSK. Like pskr1 mutants, a tpst T-DNA insertion line exhibited enhanced MAMP-triggered seedling growth inhibition, which was suppressed by exogenous application of PSK. Thus, PSK signaling mediated by PSKR1 attenuates PTI but stimulates growth.

  15. 10 CFR 37.75 - Preplanning and coordination of shipment of category 1 or category 2 quantities of radioactive...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... category 2 quantities of radioactive material. 37.75 Section 37.75 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL Physical Protection in... radioactive material. (a) Each licensee that plans to transport, or deliver to a carrier for...

  16. Another look at interpreting risk categories.

    PubMed

    Mossman, Douglas

    2006-01-01

    Several studies over the past decade have shown that simple rating scales can accurately rank sex offenders' long-term risk of recidivism. But when using these scales as prediction tools, evaluators often wish to translate categories of risk into probabilities of recidivism. D. M. Doren (2004) has recently suggested that evaluators may use the recidivism percentages published in original studies of the RRASOR and STATIC-99 without regard to differences in populations or base rates. This article explains why Doren's computations should lead to a different conclusion, and describes how simply comparing percentages across studies can mislead researchers and clinicians. Instead, investigators should isolate and examine the detection properties of risk assessment instruments alone, independent of the population- or setting-specific base rate. This article explains this process, using an imaginary study to illustrate how base rates and the properties of risk assessment instruments yield estimated probabilities of recidivism. The article also shows why Doren's results imply that the percentages of recidivism associated with scores on the RRASOR and STATIC-99 scores may vary across study populations. The article offers recommendations for researchers who design and evaluate actuarial methods of assessing risk and for clinicians who interpret results from risk assessment instruments.

  17. Are There Natural Categories of Solar Wind?

    NASA Astrophysics Data System (ADS)

    Roberts, D. A.; Sipes, T.; Karimabadi, H.

    2014-12-01

    What seem to be the most obvious categories of solar wind, such as fast and slow, often turn out to be difficult to pin down on closer examination. For example, while slow winds tend to be dense and nonAlfvenic, there are significant exceptions, with some slow winds being not only very Alfvenic but also exhibiting many fast wind traits. Here we use "unsupervised" data mining to look for "natural" solar wind types. We use a set of variables to represent the state of the system and apply what are now standard algorithms to look for natural clustering of these variables. We have done this process for the solar wind density, speed, a carbon charge state ratio (6+ to 5+), the cross-helicity, and the "residual energy." When using the first three of these, we find two groups that tend to be slow and fast, but with the boundary between the groups that is a combination of speed and density. When all five variables are used, the best characterization of the states is as three basic groups in the cross-helicity vs residual energy space, i.e., in terms of "turbulence" measures rather than simple parameters. The three-variable case is largely but not completely reproduced in its subspace. We will suggest what the results could mean for the understanding of issues such as solar wind acceleration.

  18. A lexical analysis of environmental sound categories.

    PubMed

    Houix, Olivier; Lemaitre, Guillaume; Misdariis, Nicolas; Susini, Patrick; Urdapilleta, Isabel

    2012-03-01

    In this article we report on listener categorization of meaningful environmental sounds. A starting point for this study was the phenomenological taxonomy proposed by Gaver (1993b). In the first experimental study, 15 participants classified 60 environmental sounds and indicated the properties shared by the sounds in each class. In a second experimental study, 30 participants classified and described 56 sounds exclusively made by solid objects. The participants were required to concentrate on the actions causing the sounds independent of the sound source. The classifications were analyzed with a specific hierarchical cluster technique that accounted for possible cross-classifications, and the verbalizations were submitted to statistical lexical analyses. The results of the first study highlighted 4 main categories of sounds: solids, liquids, gases, and machines. The results of the second study indicated a distinction between discrete interactions (e.g., impacts) and continuous interactions (e.g., tearing) and suggested that actions and objects were not independent organizational principles. We propose a general structure of environmental sound categorization based on the sounds' temporal patterning, which has practical implications for the automatic classification of environmental sounds.

  19. The Cape Observatory: all Categories of Heritage

    NASA Astrophysics Data System (ADS)

    Glass, Ian S.

    2012-09-01

    In this presentation I will give an outline of the various types of heritage related to the Royal Observatory, Cape of Good Hope, established in 1820 and now the headquarters campus of the South African Astronomical Observatory, located quite close to downtown Cape Town. In terms of tangible, fixed heritage, the campus itself, the domes and the various other buildings are obviously relevant. This category includes the Classical Revival Main Building of 1828 and the McClean dome of 1895 by the leading colonial architect Herbert Baker as well as many other buildings and even the graves of two directors. Tangible movable items include, in principle, the telescopes, the accessory instruments and many pieces of apparatus that have been preserved. In addition, extensive collections of antique paintings, drawings, furniture and books add to the site's cultural significance. Many of the Observatory's archives are still kept locally. The intangible heritage of the Observatory consists for example of its history, its major discoveries, its interaction with the City, its central role in the history of science in South Africa and its appeal as a living cultural institution. Especially notable were the observations by Henderson (ca 1831) leading to the distance of a Cen and the early sky survey known as the Cape Photographic Durchmusterung.

  20. Enhancing bioremediation

    SciTech Connect

    Koenigsberg, S.

    1997-02-01

    Oxygen is often the limiting factor in aerobic bioremediation. Without adequate oxygen, contaminant degradation will either cease or proceed by highly inefficient anaerobic processes. Researchers at Regenesis Bioremediation Products recently develope a technology to combat this problem, Oxygen Release Compound (ORC) a unique formulation of magnesium peroxide release oxygen slowly when hydrated. ORC is idea for supporting bioremediation of underground storage tank releases. ORC treatment represents a low intensity approach to remediation - simple, passive, low-cost, long term enhancement of a natural attenuation. 1 fig.

  1. Comparing English, Mandarin, and Russian Hydrographic and Terrain Categories

    SciTech Connect

    Feng, Chen-Chieh; Sorokine, Alexandre

    2013-01-01

    The paper compares hydrographic and terrain categories in the geospatial data standards of the US, Taiwan, and Russian Federation where the dominant languages used are from di erent language families. It aims to identify structural and semantic di erences between similar categories across three geospatial data standards. By formalizing the data standard structures and identifying the properties that di erentiate sibling categories in each geospatial data standard using well-known formal relations and quality universals, we develop a common basis on which hydrographic and terrain categories in the three data standards can be compared. The result suggests that all three data standards structure categories with a mixture of relations with di erent meaning even though most of them are well-known relations in top-level ontologies. Similar categories can be found across all three standards but exact match between similar categories are rare.

  2. On the classification of weakly integral modular categories

    SciTech Connect

    Bruillard, Paul; Galindo, César; Ng, Siu-Hung; Plavnik, Julia Y.; Rowell, Eric C.; Wang, Zhenghan

    2016-06-01

    In this paper we classify all modular categories of dimension 4m, where m is an odd square-free integer, and all rank 6 and rank 7 weakly integral modular categories. This completes the classification of weakly integral modular categories through rank 7. In particular, our results imply that all integral modular categories of rank at most 7 are pointed (that is, every simple object has dimension 1). All the non-integral (but weakly integral) modular categories of ranks 6 and 7 have dimension 4m, with m an odd square free integer, so their classification is an application of our main result. The classification of rank 7 integral modular categories is facilitated by an analysis of the two group actions on modular categories: the Galois group of the field generated by the entries of the S-matrix and the group of invertible isomorphism classes of objects. We derive some valuable arithmetic consequences from these actions.

  3. Category Number Impacts Rule-Based "and" Information-Integration Category Learning: A Reassessment of Evidence for Dissociable Category-Learning Systems

    ERIC Educational Resources Information Center

    Stanton, Roger D.; Nosofsky, Robert M.

    2013-01-01

    Researchers have proposed that an explicit reasoning system is responsible for learning rule-based category structures and that a separate implicit, procedural-learning system is responsible for learning information-integration category structures. As evidence for this multiple-system hypothesis, researchers report a dissociation based on…

  4. Limits of generalization between categories and implications for theories of category specificity.

    PubMed

    Bukach, Cindy M; Phillips, W Stewart; Gauthier, Isabel

    2010-10-01

    Both domain-specific and expertise accounts of category specialization assume that generalization occurs within a domain but not between domains. Yet it is often difficult to define the boundaries and critical features of object domains. Differences in how categories are defined make it difficult to adjudicate between accounts of category specificity and may lead to contradictory results. For example, evidence for whether car experts recruit the fusiform face area is mixed, and this inconsistency may be due to the inclusion of antique cars in one of those previous studies (e.g., Grill-Spector, Knouf, & Kanwisher, 2004). The present study tested the generalization of expertise from modern to antique cars and found that modern-car experts showed expert discrimination and holistic processing of modern cars but not of antique cars. These findings suggest that the neural specialization underlying perceptual expertise is highly specific and may not generalize to distinct subclasses, even when they share some degree of perceptual and conceptual features.

  5. REINFORCER MAGNITUDE ATTENUATES

    PubMed Central

    Pinkston, Jonathan W.; Lamb, R. J.

    2012-01-01

    When given to pigeons, the direct-acting dopamine agonist apomorphine elicits pecking. The response has been likened to foraging pecking because it bears remarkable similarity to foraging behavior, and it is enhanced by food deprivation. On the other hand, other data suggest the response is not related to foraging behavior and may even interfere with food ingestion. Although elicited pecking interferes with food capture, it may selectively alter procurement phases of feeding, which can be isolated in operant preparations. To explore the relation between operant and elicited pecking, we provided pigeons the opportunity to earn different reinforcer magnitudes during experimental sessions. During signaled components, each of 4 pigeons could earn 2-, 4-, or 8-s access to grain for a single peck made at the end of a 5-min interval. In general, responding increased as a function of reinforcer magnitude. Apomorphine increased pecking for 2 pigeons and decreased pecking for the other 2. In both cases, apomorphine was more potent under the component providing the smallest reinforcer magnitude. Analysis of the pattern of pecking across the interval indicated that behavior lost its temporal organization as dose increased. Because apomorphine-induced pecking varied inversely with reinforcer magnitude, we conclude that elicited pecks are not functionally related to food procurement. The data are consistent with the literature on behavioral resistance to change and suggest that the effects of apomorphine may be modulated by prevailing stimulus–reinforcer relationships. PMID:23144505

  6. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    SciTech Connect

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-04-01

    In this report we will show results of seismic and well log derived attenuation attributes from a deep water Gulf of Mexico data set. This data was contributed by Burlington Resources and Seitel Inc. The data consists of ten square kilometers of 3D seismic data and three well penetrations. We have computed anomalous seismic absorption attributes on the seismic data and have computed Q from the well log curves. The results show a good correlation between the anomalous absorption (attenuation) attributes and the presence of gas as indicated by well logs.

  7. Functional categories for future flight deck designs

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.

    1993-01-01

    With the addition of each new system on the flight deck, the danger of increasing overall operator workload while reducing crew understanding of critical mission information exists. The introduction of more powerful onboard computers, larger databases, and the increased use of electronic display media may lead to a situation of flight deck 'sophistication' at the expense of losses in flight crew capabilities and situational awareness. To counter this potentially negative impact of new technology, research activities are underway to reassess the flight deck design process. The fundamental premise of these activities is that a human-centered, systems-oriented approach to the development of advanced civil aircraft flight decks will be required for future designs to remain ergonomically sound and economically competitive. One of the initial steps in an integrated flight deck process is to define the primary flight deck functions needed to support the mission goals of the vehicle. This would allow the design team to evaluate candidate concepts in relation to their effectiveness in meeting the functional requirements. In addition, this would provide a framework to aid in categorizing and bookkeeping all of the activities that are required to be performed on the flight deck, not just activities of the crew or of a specific system. This could then allow for a better understanding and allocation of activities in the design, an understanding of the impact of a specific system on overall system performance, and an awareness of the total crew performance requirements for the design. One candidate set of functional categories that could be used to guide an advanced flight deck design are described.

  8. Vinpocetine attenuates lipid accumulation and atherosclerosis formation

    SciTech Connect

    Cai, Yujun; Li, Jian-Dong; Yan, Chen

    2013-05-10

    Highlights: •Vinpocetine attenuates hyperlipidemia-induced atherosclerosis in a mouse model. •Vinpocetine antagonizes ox-LDL uptake and accumulation in macrophages. •Vinpocetine blocks the induction of ox-LDL receptor LOX-1 in vitro and in vivo. -- Abstract: Atherosclerosis, the major cause of myocardial infarction and stroke, is a chronic arterial disease characterized by lipid deposition and inflammation in the vessel wall. Cholesterol, in low-density lipoprotein (LDL), plays a critical role in the pathogenesis of atherosclerosis. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. Recent study indicated that vinpocetine is a potent anti-inflammatory agent. However, its role in the pathogenesis of atherosclerosis remains unexplored. In the present study, we show that vinpocetine significantly reduced atherosclerotic lesion formation in ApoE knockout mice fed with a high-fat diet. In cultured murine macrophage RAW264.7 cells, vinpocetine markedly attenuated oxidized LDL (ox-LDL) uptake and foam cell formation. Moreover, vinpocetine greatly blocked the induction of ox-LDL receptor 1 (LOX-1) in cultured macrophages as well as in the LOX-1 level in atherosclerotic lesions. Taken together, our data reveal a novel role of vinpocetine in reduction of pathogenesis of atherosclerosis, at least partially through suppressing LOX-1 signaling pathway. Given the excellent safety profile of vinpocetine, this study suggests vinpocetine may be a therapeutic candidate for treating atherosclerosis.

  9. AOSC multichannel electronic variable optical attenuator

    NASA Astrophysics Data System (ADS)

    Vonsovici, Adrian P.; Day, Ian E.; House, Andrew A.; Asghari, Mehdi

    2001-05-01

    Optical networks are becoming a reality as the physical layer of high-performance telecommunication networks. The deployment of wavelength-division multiplexing (WDM) technology allows the extended exploitation of installed fibers now facing an increasing traffic capacity demand. Performances of such systems can be degraded by wide variations of the optical channel power following propagation in the network. Therefore a tilt control of optical amplifiers in WDM networks and dynamic channel power regulation and equalisation in cross-connected nodes is necessary. An important tool for the system designer is the variable optical attenuator (VOA). We present the design and the realization of newly developed VOAs using the ASOC technology. This technology refers to the fabrication of integrated optics components in silicon-on-insulator (SOI) material. The device is based on the light absorption by the free-carriers that are injected in the core of a rib waveguide from a p-i-n diode. The devices incorporate horizontally and vertically tapered waveguides for minimum fiber coupling loss. The p-i-n diode for carrier injection into the active region of the rib waveguide was optimised in order to enhance the attenuation. One major advantage of the ASOC technology is the possibility of monolithic integration of many integrated optics devices on one chip. In the light of this the paper illustrates the result of characterisation of multichannel VOAs.

  10. Natural attenuation processes during in situ capping.

    PubMed

    Himmelheber, David W; Pennell, Kurt D; Hughes, Joseph B

    2007-08-01

    Chlorinated solvents are common groundwater contaminants that threaten surface water quality and benthic health when present in groundwater seeps. Aquatic sediments can act as natural biobarriers to detoxify chlorinated solvent plumes via reductive dechlorination. In situ sediment capping, a remedial technique in which clean material is placed at the sediment-water interface, may alter sedimentary natural attenuation processes. This research explores the potential of Anacostia River sediment to naturally attenuate chlorinated solvents under simulated capping conditions. Results of microcosm studies demonstrated that intrinsic dechlorination of dissolved-phase PCE to ethene was possible, with electron donor availability controlling microbial activity. A diverse microbial community was present in the sediment, including multiple Dehalococcoides strains indicated by the amplification of the reductive dehalogenases tceA, vcrA, and bvcA. An upflow column simulating a capped sediment bed subject to PCE-contaminated groundwater seepage lost dechlorination activity with time and only achieved complete dechlorination when microorganisms present in the sediment were provided electron donor. Increases in effluent chloroethene concentrations during the period of biostimulation were attributed to biologically enhanced desorption and the formation of less sorptive dechlorination products. These findings suggest that in situ caps should be designed to account for reductions in natural biobarrier reactivity and for the potential breakthrough of groundwater contaminants.

  11. Phase noise reveals early category-specific modulation of the event-related potentials.

    PubMed

    Németh, Kornél; Kovács, Petra; Vakli, Pál; Kovács, Gyula; Zimmer, Márta

    2014-01-01

    Previous studies have found that the amplitude of the early event-related potential (ERP) components evoked by faces, such as N170 and P2, changes systematically as a function of noise added to the stimuli. This change has been linked to an increased perceptual processing demand and to enhanced difficulty in perceptual decision making about faces. However, to date it has not yet been tested whether noise manipulation affects the neural correlates of decisions about face and non-face stimuli similarly. To this end, we measured the ERPs for faces and cars at three different phase noise levels. Subjects performed the same two-alternative age-discrimination task on stimuli chosen from young-old morphing continua that were created from faces as well as cars and were calibrated to lead to similar performances at each noise-level. Adding phase noise to the stimuli reduced performance and enhanced response latency for the two categories to the same extent. Parallel to that, phase noise reduced the amplitude and prolonged the latency of the face-specific N170 component. The amplitude of the P1 showed category-specific noise dependence: it was enhanced over the right hemisphere for cars and over the left hemisphere for faces as a result of adding phase noise to the stimuli, but remained stable across noise levels for cars over the left and for faces over the right hemisphere. Moreover, noise modulation altered the category-selectivity of the N170, while the P2 ERP component, typically associated with task decision difficulty, was larger for the more noisy stimuli regardless of stimulus category. Our results suggest that the category-specificity of noise-induced modulations of ERP responses starts at around 100 ms post-stimulus.

  12. Enhanced cytotoxicity with a novel system combining the paclitaxel-2'-ethylcarbonate prodrug and an HSV amplicon with an attenuated replication-competent virus, HF10 as a helper virus.

    PubMed

    Ishida, Daisuke; Nawa, Akihiro; Tanino, Tadatoshi; Goshima, Fumi; Luo, Chen Hong; Iwaki, Masahiro; Kajiyama, Hiroaki; Shibata, Kiyosumi; Yamamoto, Eiko; Ino, Kazuhiko; Tsurumi, Tatsuya; Nishiyama, Yukihiro; Kikkawa, Fumitaka

    2010-02-01

    We previously demonstrated that HF10, which is a natural, non-engineered HSV-1, has potent oncolytic activity in the treatment of solid malignant tumors in vitro and in vivo [H. Takakuwa, F. Goshima, N. Nozawa, T. Yoshikawa, H. Kimata, A. Nakao, et al., Oncolytic viral therapy using a spontaneously generated herpes simplex virus type 1 variant for disseminated peritoneal tumor in immunocompetent mice, Arch. Virol. 148 (2003) 813-825; S. Kohno, C. Lou, F. Goshima, Y. Nishiyama, T. Sata, Y. Ono, Herpes simplex virus type 1 mutant HF10 oncolytic viral therapy for bladder cancer, Urology 66 (2005) 1116-1121; D. Watanabe, F. Goshima, I. Mori, Y. Tamada, Y. Matsumoto, Y. Nishiyama, Oncolytic virotherapy for malignant melanoma with herpes simplex virus type 1 mutant HF10, J. Dermatol. Sci. 50 (2008) 185-196; A. Nawa, C. Luo, L. Zhang, Y. Ushijima, D. Ishida, M. Kamakura, et al., Non-engineered, naturally oncolytic herpes simplex virus HSV1 HF10: applications for cancer gene therapy, Curr. Gene. Ther. 8 (2008) 208-221]. Previous reports have also shown that a combination of HF10 and paclitaxel (TAX) was more efficacious than either regimen alone for some types of malignant tumors [S. Shimoyama, F. Goshima, O. Teshigahara, H. Kasuya, Y. Kodera, A. Nakao, et al., Enhanced efficacy of herpes simplex virus mutant HF10 combined with paclitaxel in peritoneal cancer dissemination models, Hepatogastroenterology 54 (2007) 1038-1042]. In this study, we investigated the efficacy of gene-directed enzyme prodrug therapy (GDEPT) using a novel system that combines the paclitaxel-2'-ethylcarbonate prodrug (TAX-2'-Et) and an HSV amplicon expressing rabbit-carboxylesterase (CES) with HF10 as a helper virus. This GDEPT system aims to produce high level of CES at the tumor site, resulting in efficient local conversion of the TAX-2'-Et prodrug into the active drug TAX [A. Nawa, T. Tanino, C. Lou, M. Iwaki, H. Kajiyama, K. Shibata, et al., Gene directed enzyme prodrug therapy for ovarian cancer

  13. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    SciTech Connect

    Joel Walls; M.T. Taner; Gary Mavko; Jack Dvorkin

    2002-07-01

    In fully-saturated rock and at ultrasonic frequencies, the microscopic squirt flow induced between the stiff and soft parts of the pore space by an elastic wave is responsible for velocity-frequency dispersion and attenuation. In the seismic frequency range, it is the macroscopic cross-flow between the stiffer and softer parts of the rock. We use the latter hypothesis to introduce simple approximate equations for velocity-frequency dispersion and attenuation in a fully water saturated reservoir. The equations are based on the assumption that in heterogeneous rock and at a very low frequency, the effective elastic modulus of the fully-saturated rock can be estimated by applying a fluid substitution procedure to the averaged (upscaled) dry frame whose effective porosity is the mean porosity and the effective elastic modulus is the Backus-average (geometric mean) of the individual dry-frame elastic moduli of parts of the rock. At a higher frequency, the effective elastic modulus of the saturated rock is the Backus-average of the individual fully-saturated-rock elastic moduli of parts of the rock. The difference between the effective elastic modulus calculated separately by these two methods determines the velocity-frequency dispersion. The corresponding attenuation is calculated from this dispersion by using (e.g.) the standard linear solid attenuation model.

  14. The linguistic construction of social categories in toddlers.

    PubMed

    Diesendruck, Gil; Deblinger-Tangi, Ronit

    2014-01-01

    Kindergarteners treat certain social categories as natural kinds. This study addressed how children pick out social categories. Ninety-one 19- and 26-month-olds were familiarized to exemplars of categories of people (e.g., Blacks-Whites, men-women) and animals (e.g., cows-horses). Participants then saw a picture matching the familiarization category and another that did not, and were asked to select which was like the familiarization pictures. For half of the participants, a label was attached to familiarization exemplars, while for the other half, no label was mentioned. The main finding was that for the younger toddlers, labels significantly improved recognition of the categories of people, but not of animals. These results are taken to support the notion that social categories are indeed culturally constructed.

  15. Right away: A late, right-lateralized category effect complements an early, left-lateralized category effect in visual search.

    PubMed

    Constable, Merryn D; Becker, Stefanie I

    2017-03-27

    According to the Sapir-Whorf hypothesis, learned semantic categories can influence early perceptual processes. A central finding in support of this view is the lateralized category effect-namely, the finding that categorically different colors (e.g., blue and green hues) can be discriminated faster than colors within the same color category (e.g., different hues of green), especially when they are presented in the right visual field. Because the right visual field projects to the left hemisphere, this finding has been popularly couched in terms of the left-lateralization of language. However, other studies have reported bilateral category effects, which has led some researchers to question the linguistic origins of the effect. Here we examined the time course of lateralized and bilateral category effects in the classical visual search paradigm by means of eyetracking and RT distribution analyses. Our results show a bilateral category effect in the manual responses, which is combined of an early, left-lateralized category effect and a later, right-lateralized category effect. The newly discovered late, right-lateralized category effect occurred only when observers had difficulty locating the target, indicating a specialization of the right hemisphere to find categorically different targets after an initial error. The finding that early and late stages of visual search show different lateralized category effects can explain a wide range of previously discrepant findings.

  16. Stormwater Attenuation by Green Roofs

    NASA Astrophysics Data System (ADS)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  17. 40 CFR 98.280 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Silicon Carbide Production § 98.280 Definition of the source category. Silicon carbide production includes any process that produces silicon carbide for...

  18. 40 CFR 98.280 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Silicon Carbide Production § 98.280 Definition of the source category. Silicon carbide production includes any process that produces silicon carbide for...

  19. 40 CFR 98.280 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Silicon Carbide Production § 98.280 Definition of the source category. Silicon carbide production includes any process that produces silicon carbide for...

  20. 40 CFR 98.280 - Definition of the source category.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Silicon Carbide Production § 98.280 Definition of the source category. Silicon carbide production includes any process that produces silicon carbide for...

  1. 40 CFR 98.280 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Silicon Carbide Production § 98.280 Definition of the source category. Silicon carbide production includes any process that produces silicon carbide for...

  2. 40 CFR 98.30 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... purposes of producing electricity, generating steam, or providing useful heat or energy for industrial... turbines, engines, incinerators, and process heaters. (b) This source category does not include:...

  3. On Anaphora and the Binding Principles in Categorial Grammar

    NASA Astrophysics Data System (ADS)

    Morrill, Glyn; Valentín, Oriol

    In type logical categorial grammar the analysis of an expression is a resource-conscious proof. Anaphora represents a particular challenge to this approach in that the antecedent resource is multiplied in the semantics. This duplication, which corresponds logically to the structural rule of contraction, may be treated lexically or syntactically. Furthermore, anaphora is subject to constraints, which Chomsky (1981) formulated as Binding Principles A, B, and C. In this paper we consider English anaphora in categorial grammar including reference to the binding principles. We invoke displacement calculus, modal categorial calculus, categorial calculus with limited contraction, and entertain addition of negation as failure.

  4. Categorial Compositionality: A Category Theory Explanation for the Systematicity of Human Cognition

    PubMed Central

    Phillips, Steven; Wilson, William H.

    2010-01-01

    Classical and Connectionist theories of cognitive architecture seek to explain systematicity (i.e., the property of human cognition whereby cognitive capacity comes in groups of related behaviours) as a consequence of syntactically and functionally compositional representations, respectively. However, both theories depend on ad hoc assumptions to exclude specific instances of these forms of compositionality (e.g. grammars, networks) that do not account for systematicity. By analogy with the Ptolemaic (i.e. geocentric) theory of planetary motion, although either theory can be made to be consistent with the data, both nonetheless fail to fully explain it. Category theory, a branch of mathematics, provides an alternative explanation based on the formal concept of adjunction, which relates a pair of structure-preserving maps, called functors. A functor generalizes the notion of a map between representational states to include a map between state transformations (or processes). In a formal sense, systematicity is a necessary consequence of a higher-order theory of cognitive architecture, in contrast to the first-order theories derived from Classicism or Connectionism. Category theory offers a re-conceptualization for cognitive science, analogous to the one that Copernicus provided for astronomy, where representational states are no longer the center of the cognitive universe—replaced by the relationships between the maps that transform them. PMID:20661306

  5. Categorial compositionality: a category theory explanation for the systematicity of human cognition.

    PubMed

    Phillips, Steven; Wilson, William H

    2010-07-22

    Classical and Connectionist theories of cognitive architecture seek to explain systematicity (i.e., the property of human cognition whereby cognitive capacity comes in groups of related behaviours) as a consequence of syntactically and functionally compositional representations, respectively. However, both theories depend on ad hoc assumptions to exclude specific instances of these forms of compositionality (e.g. grammars, networks) that do not account for systematicity. By analogy with the Ptolemaic (i.e. geocentric) theory of planetary motion, although either theory can be made to be consistent with the data, both nonetheless fail to fully explain it. Category theory, a branch of mathematics, provides an alternative explanation based on the formal concept of adjunction, which relates a pair of structure-preserving maps, called functors. A functor generalizes the notion of a map between representational states to include a map between state transformations (or processes). In a formal sense, systematicity is a necessary consequence of a higher-order theory of cognitive architecture, in contrast to the first-order theories derived from Classicism or Connectionism. Category theory offers a re-conceptualization for cognitive science, analogous to the one that Copernicus provided for astronomy, where representational states are no longer the center of the cognitive universe--replaced by the relationships between the maps that transform them.

  6. Color categories only affect post-perceptual processes when same- and different-category colors are equally discriminable.

    PubMed

    He, Xun; Witzel, Christoph; Forder, Lewis; Clifford, Alexandra; Franklin, Anna

    2014-04-01

    Prior claims that color categories affect color perception are confounded by inequalities in the color space used to equate same- and different-category colors. Here, we equate same- and different-category colors in the number of just-noticeable differences, and measure event-related potentials (ERPs) to these colors on a visual oddball task to establish if color categories affect perceptual or post-perceptual stages of processing. Category effects were found from 200 ms after color presentation, only in ERP components that reflect post-perceptual processes (e.g., N2, P3). The findings suggest that color categories affect post-perceptual processing, but do not affect the perceptual representation of color.

  7. Ferrite attenuator modulation improves antenna performance

    NASA Technical Reports Server (NTRS)

    Hooks, J. C.; Larson, S. G.; Shorkley, F. H.; Williams, B. T.

    1970-01-01

    Ferrite attenuator inserted into appropriate waveguide reduces the gain of the antenna element which is causing interference. Modulating the ferrite attenuator to change the antenna gain at the receive frequency permits ground tracking until the antenna is no longer needed.

  8. Tumor volume of resectable gastric adenocarcinoma on multidetector computed tomography: association with N categories

    PubMed Central

    Li, Hang; Chen, Xiao-li; Li, Jun-ru; Li, Zhen-lin; Chen, Tian-wu; Pu, Hong; Yin, Long-lin; Xu, Guo-hui; Li, Zhen-wen; Reng, Jing; Zhou, Peng; Cheng, Zhu-zhong; Cao, Ying

    2016-01-01

    OBJECTIVE: To determine whether the gross tumor volume of resectable gastric adenocarcinoma on multidetector computed tomography could predict the presence of regional lymph node metastasis and could determine N categories. MATERIALS AND METHODS: A total of 202 consecutive patients with gastric adenocarcinoma who had undergone gastrectomy 1 week after contrast-enhanced multidetector computed tomography were retrospectively identified. The gross tumor volume was evaluated on multidetector computed tomography images. Univariate and multivariate analyses were performed to determine whether the gross tumor volume could predict regional lymph node metastasis, and the Mann-Whitney U test was performed to compare the gross tumor volume among N categories. Additionally, a receiver operating characteristic analysis was performed to identify the accuracy of the gross tumor volume in differentiating N categories. RESULTS: The gross tumor volume could predict regional lymph node metastasis (p<0.0001) in the univariate analysis, and the multivariate analyses indicated that the gross tumor volume was an independent risk factor for regional lymph node metastasis (p=0.005, odds ratio=1.364). The Mann-Whitney U test showed that the gross tumor volume could distinguish N0 from the N1-N3 categories, N0-N1 from N2-N3, and N0-N2 from N3 (all p<0.0001). In the T1-T4a categories, the gross tumor volume could differentiate N0 from the N1-N3 categories (cutoff, 12.3 cm3), N0-N1 from N2-N3 (cutoff, 16.6 cm3), and N0-N2 from N3 (cutoff, 24.6 cm3). In the T4a category, the gross tumor volume could differentiate N0 from the N1-N3 categories (cutoff, 15.8 cm3), N0-N1 from N2-N3 (cutoff, 17.8 cm3), and N0-N2 from N3 (cutoff, 24 cm3). CONCLUSION: The gross tumor volume of resectable gastric adenocarcinoma on multidetector computed tomography could predict regional lymph node metastasis and N categories. PMID:27166769

  9. Chromatic Perceptual Learning but No Category Effects without Linguistic Input

    PubMed Central

    Grandison, Alexandra; Sowden, Paul T.; Drivonikou, Vicky G.; Notman, Leslie A.; Alexander, Iona; Davies, Ian R. L.

    2016-01-01

    Perceptual learning involves an improvement in perceptual judgment with practice, which is often specific to stimulus or task factors. Perceptual learning has been shown on a range of visual tasks but very little research has explored chromatic perceptual learning. Here, we use two low level perceptual threshold tasks and a supra-threshold target detection task to assess chromatic perceptual learning and category effects. Experiment 1 investigates whether chromatic thresholds reduce as a result of training and at what level of analysis learning effects occur. Experiment 2 explores the effect of category training on chromatic thresholds, whether training of this nature is category specific and whether it can induce categorical responding. Experiment 3 investigates the effect of category training on a higher level, lateralized target detection task, previously found to be sensitive to category effects. The findings indicate that performance on a perceptual threshold task improves following training but improvements do not transfer across retinal location or hue. Therefore, chromatic perceptual learning is category specific and can occur at relatively early stages of visual analysis. Additionally, category training does not induce category effects on a low level perceptual threshold task, as indicated by comparable discrimination thresholds at the newly learned hue boundary and adjacent test points. However, category training does induce emerging category effects on a supra-threshold target detection task. Whilst chromatic perceptual learning is possible, learnt category effects appear to be a product of left hemisphere processing, and may require the input of higher level linguistic coding processes in order to manifest. PMID:27252669

  10. Category selectivity in human visual cortex: Beyond visual object recognition.

    PubMed

    Peelen, Marius V; Downing, Paul E

    2017-04-02

    Human ventral temporal cortex shows a categorical organization, with regions responding selectively to faces, bodies, tools, scenes, words, and other categories. Why is this? Traditional accounts explain category selectivity as arising within a hierarchical system dedicated to visual object recognition. For example, it has been proposed that category selectivity reflects the clustering of category-associated visual feature representations, or that it reflects category-specific computational algorithms needed to achieve view invariance. This visual object recognition framework has gained renewed interest with the success of deep neural network models trained to "recognize" objects: these hierarchical feed-forward networks show similarities to human visual cortex, including categorical separability. We argue that the object recognition framework is unlikely to fully account for category selectivity in visual cortex. Instead, we consider category selectivity in the context of other functions such as navigation, social cognition, tool use, and reading. Category-selective regions are activated during such tasks even in the absence of visual input and even in individuals with no prior visual experience. Further, they are engaged in close connections with broader domain-specific networks. Considering the diverse functions of these networks, category-selective regions likely encode their preferred stimuli in highly idiosyncratic formats; representations that are useful for navigation, social cognition, or reading are unlikely to be meaningfully similar to each other and to varying degrees may not be entirely visual. The demand for specific types of representations to support category-associated tasks may best account for category selectivity in visual cortex. This broader view invites new experimental and computational approaches.

  11. Chlorine signal attenuation in concrete.

    PubMed

    Naqvi, A A; Maslehuddin, M; ur-Rehman, Khateeb; Al-Amoudi, O S B

    2015-11-01

    The intensity of prompt gamma-ray was measured at various depths from chlorine-contaminated silica fume (SF) concrete slab concrete specimens using portable neutron generator-based prompt gamma-ray setup. The intensity of 6.11MeV chloride gamma-rays was measured from the chloride contaminated slab at distance of 15.25, 20.25, 25.25, 30.25 and 35.25cm from neutron target in a SF cement concrete slab specimens. Due to attenuation of thermal neutron flux and emitted gamma-ray intensity in SF cement concrete at various depths, the measured intensity of chlorine gamma-rays decreases non-linearly with increasing depth in concrete. A good agreement was noted between the experimental results and the results of Monte Carlo simulation. This study has provided useful experimental data for evaluating the chloride contamination in the SF concrete utilizing gamma-ray attenuation method.

  12. Ultrasound fields in attenuating media.

    PubMed

    Lerch, R; Friedrich, W

    1986-10-01

    For medical ultrasonic imaging and for nondestructive testing, the attenuation of pressure waves and the resulting shift in wave velocity are important features in commonly used transmission media such as biological tissue. An algorithm for the numerical evaluation of pressure field distributions generated by ultrasonic transducers is presented. The attenuation and dispersion of the sound transmission medium are taken into consideration. The sound fields are computed numerically for continuous wave as well as pulse excitation. The transducer has plane or gently curved geometry and is embedded in a plane rigid baffle. The numerically determined pressure fields are presented as 3D plots, as gray-scale images for a fixed time stamp (like a snapshot), or as isobars regarding the maximum values over time for each local point in the area under investigation. The algorithm described here can be utilized as a tool for design of ultrasound transducers, especially array antennas.

  13. 40 CFR 98.300 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Definition of the source category. 98.300 Section 98.300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS....300 Definition of the source category. (a) The electrical transmission and distribution equipment...

  14. 40 CFR 98.300 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Definition of the source category. 98.300 Section 98.300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS....300 Definition of the source category. (a) The electrical transmission and distribution equipment...

  15. 40 CFR 98.460 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Industrial Waste Landfills § 98.460 Definition of the source category. (a) This source category applies to industrial waste landfills that accepted waste on or after... or equal to 300,000 metric tons. (b) An industrial waste landfill is a landfill other than...

  16. 40 CFR 98.460 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Industrial Waste Landfills § 98.460 Definition of the source category. (a) This source category applies to industrial waste landfills that accepted waste on or after... or equal to 300,000 metric tons. (b) An industrial waste landfill is a landfill other than...

  17. 77 FR 10352 - Airworthiness Directives; Various Transport Category Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-22

    ... Category Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are revising an existing airworthiness directive (AD) for transport category airplanes that have one or more...; establishment of a procedure to announce to airplane occupants that smoking is prohibited in the...

  18. 36 CFR 292.22 - Land category assignments.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... availability of this map or maps in the local newspapers of record. (b) Changes in land category assignment... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Land category assignments... NATIONAL RECREATION AREAS Hells Canyon National Recreation Area-Private Lands § 292.22 Land...

  19. 76 FR 12141 - New Postal Product and New Price Category

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ... New Postal Product and New Price Category AGENCY: Postal Regulatory Commission. ACTION: Notice... Services to the competitive product list. The Postal Service also states that it has established a new... new product to the competitive product list and concurrently establish a new price category under...

  20. 34 CFR 75.264 - Transfers among budget categories.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 1 2013-07-01 2013-07-01 false Transfers among budget categories. 75.264 Section 75.264 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS How Grants Are Made Miscellaneous § 75.264 Transfers among budget categories. A grantee may, notwithstanding...

  1. 34 CFR 75.264 - Transfers among budget categories.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Transfers among budget categories. 75.264 Section 75.264 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS How Grants Are Made Miscellaneous § 75.264 Transfers among budget categories. A grantee may, notwithstanding...

  2. 34 CFR 75.264 - Transfers among budget categories.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 1 2014-07-01 2014-07-01 false Transfers among budget categories. 75.264 Section 75.264 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS How Grants Are Made Miscellaneous § 75.264 Transfers among budget categories. A grantee may, notwithstanding...

  3. 34 CFR 75.264 - Transfers among budget categories.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false Transfers among budget categories. 75.264 Section 75.264 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS How Grants Are Made Miscellaneous § 75.264 Transfers among budget categories. A grantee may, notwithstanding...

  4. A comparison of different category scales for estimating disease severity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant pathologists most often obtain quantitative information on disease severity using visual assessments. Category scales are widely used for assessing disease severity, including for screening germplasm. The most widely used category scale is the Horsfall-Barratt (H-B) scale, but reports show tha...

  5. What interval characteristics make a good disease assessment category scale

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant pathologists most often obtain quantitative information on disease severity using visual assessments. Category scales have been used for assessing plant disease severity in field experiments, epidemiological studies, and for screening germplasm. The most widely used category scale is the Horsf...

  6. Accounting for a Functional Category: German "Drohen" "to Threaten"

    ERIC Educational Resources Information Center

    Heine, Bernd; Miyashita, Hiroyuki

    2008-01-01

    In many languages there are words that behave like lexical verbs and on the one hand and like functional categories expressing distinctions of tense, aspect, modality, etc. on the other. The grammatical status of such words is frequently controversial; while some authors treat them as belonging to one and the same grammatical category, others…

  7. 32 CFR 901.17 - Foreign students category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Foreign students category. 901.17 Section 901.17 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE MILITARY TRAINING AND... Foreign students category. (a) The Academy is authorized to provide instruction to as many as 40...

  8. 32 CFR 901.17 - Foreign students category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Foreign students category. 901.17 Section 901.17 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE MILITARY TRAINING AND... Foreign students category. (a) The Academy is authorized to provide instruction to as many as 40...

  9. 32 CFR 901.17 - Foreign students category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Foreign students category. 901.17 Section 901.17 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE MILITARY TRAINING AND... Foreign students category. (a) The Academy is authorized to provide instruction to as many as 40...

  10. 32 CFR 901.17 - Foreign students category.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Foreign students category. 901.17 Section 901.17 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE MILITARY TRAINING AND... Foreign students category. (a) The Academy is authorized to provide instruction to as many as 40...

  11. 32 CFR 901.17 - Foreign students category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Foreign students category. 901.17 Section 901.17 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE MILITARY TRAINING AND... Foreign students category. (a) The Academy is authorized to provide instruction to as many as 40...

  12. 34 CFR 75.264 - Transfers among budget categories.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Transfers among budget categories. 75.264 Section 75.264 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS How Grants Are Made Miscellaneous § 75.264 Transfers among budget categories. A grantee may, notwithstanding...

  13. 14 CFR 121.199 - Nontransport category airplanes: Takeoff limitations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Nontransport category airplanes: Takeoff... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.199 Nontransport category airplanes: Takeoff limitations. (a) No person operating...

  14. 14 CFR 121.199 - Nontransport category airplanes: Takeoff limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Nontransport category airplanes: Takeoff... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.199 Nontransport category airplanes: Takeoff limitations. (a) No person operating...

  15. Decoding the neural representation of fine-grained conceptual categories.

    PubMed

    Ghio, Marta; Vaghi, Matilde Maria Serena; Perani, Daniela; Tettamanti, Marco

    2016-05-15

    Neuroscientific research on conceptual knowledge based on the grounded cognition framework has shed light on the organization of concrete concepts into semantic categories that rely on different types of experiential information. Abstract concepts have traditionally been investigated as an undifferentiated whole, and have only recently been addressed in a grounded cognition perspective. The present fMRI study investigated the involvement of brain systems coding for experiential information in the conceptual processing of fine-grained semantic categories along the abstract-concrete continuum. These categories consisted of mental state-, emotion-, mathematics-, mouth action-, hand action-, and leg action-related meanings. Thirty-five sentences for each category were used as stimuli in a 1-back task performed by 36 healthy participants. A univariate analysis failed to reveal category-specific activations. Multivariate pattern analyses, in turn, revealed that fMRI data contained sufficient information to disentangle all six fine-grained semantic categories across participants. However, the category-specific activity patterns showed no overlap with the regions coding for experiential information. These findings demonstrate the possibility of detecting specific patterns of neural representation associated with the processing of fine-grained conceptual categories, crucially including abstract ones, though bearing no anatomical correspondence with regions coding for experiential information as predicted by the grounded cognition hypothesis.

  16. 41 CFR 105-62.101 - Security classification categories.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... three categories: Namely, Top Secret, Secret, or Confidential, depending on its degree of significance... provided by statute. The three classification categories are defined as follows: (a) Top Secret. Top Secret... with the utmost restraint. (b) Secret. Secret refers to that national security information or...

  17. 40 CFR 98.340 - Definition of the source category.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Recovery Act (RCRA) Subtitle C or Toxic Substances Control Act (TSCA) hazardous waste landfills... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Municipal Solid Waste Landfills § 98.340 Definition of the source category. (a) This source category applies to municipal solid waste (MSW) landfills that...

  18. 40 CFR 98.340 - Definition of the source category.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Recovery Act (RCRA) Subtitle C or Toxic Substances Control Act (TSCA) hazardous waste landfills... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Municipal Solid Waste Landfills § 98.340 Definition of the source category. (a) This source category applies to municipal solid waste (MSW) landfills that...

  19. 40 CFR 98.340 - Definition of the source category.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Municipal Solid Waste Landfills § 98.340 Definition of the source category. (a) This source category applies to municipal solid waste (MSW) landfills that accepted waste on or after January 1, 1980, unless all three of the following conditions apply. (1) The...

  20. 40 CFR 98.340 - Definition of the source category.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Recovery Act (RCRA) Subtitle C or Toxic Substances Control Act (TSCA) hazardous waste landfills... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Municipal Solid Waste Landfills § 98.340 Definition of the source category. (a) This source category applies to municipal solid waste (MSW) landfills that...