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Sample records for active principles present

  1. Adult Learning Principles and Presentation Pearls

    PubMed Central

    Palis, Ana G.; Quiros, Peter A.

    2014-01-01

    Although lectures are one of the most common methods of knowledge transfer in medicine, their effectiveness has been questioned. Passive formats, lack of relevance and disconnection from the student's needs are some of the arguments supporting this apparent lack of efficacy. However, many authors have suggested that applying adult learning principles (i.e., relevance, congruence with student's needs, interactivity, connection to student's previous knowledge and experience) to this method increases learning by lectures and the effectiveness of lectures. This paper presents recommendations for applying adult learning principles during planning, creation and development of lectures to make them more effective. PMID:24791101

  2. Causality principles in solar activity -climate relations.

    NASA Astrophysics Data System (ADS)

    Stauning, Peter

    The relations between solar activity and the terrestrial climate have quite often been inves-tigated. In most cases the analyses have been based on comparisons between time series of solar activity parameters, for instance sunspot numbers, and terrestrial climate parameters, for instance global temperatures. However, many of the reported close relations are based on skilfully manipulated data and neglect of basic causality principles. For cause-effect relations to be reliably established, the variations in the causative function must obviously happen prior to the related effects. Thus it is problematic to use, for instance, running averages of parameters, if the result depends too much on posterior elements of the causative time series or precursory elements of the effects. Even more neglected are the causality principles for cause-effect rela-tions with a strongly varying source function, like for instance the 11 year solar activity cycle. In such cases damping of source variations by smoothing data series, introduces additional im-plied delays, which should be considered in the judgement of apparent correlations between the processed time series of cause and effect parameters. The presentation shall illustrate causal-ity relations between solar activity and terrestrial climate parameters and discuss examples of frequently quoted solar activity-climate relations, which violate basic causality principles.

  3. A Filmed Presentation of Ecological Principles. Final Report.

    ERIC Educational Resources Information Center

    Robinson, Gerald G.; Nelson, Gid E.

    Procedures in developing a 66-minute film entitled "Natural Communities of Florida; Physical Factors and Distribution" and presented in this summary report. Production of the film was undertaken in an attempt to provide a more effective means of presenting basic ecological principles to students in introductory, college level biology courses. The…

  4. Computer Technology Can Enhance Presentation of Pharmacological Principles.

    ERIC Educational Resources Information Center

    Riffee, William H.

    1991-01-01

    The use of liquid crystal display (LCD) techniques for projection of computer monitor images onto a large screen for classroom viewing is discussed and illustrated with a pharmacology class presentation on drug/neurotransmitter-receptor interactions. The method is seen as a way of bringing a new dynamic to visual instruction. (MSE)

  5. Simple Activity Demonstrates Wind Energy Principles

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    Wind energy is an exciting and clean energy option often described as the fastest-growing energy system on the planet. With some simple materials, teachers can easily demonstrate its key principles in their classroom. (Contains 1 figure and 2 tables.)

  6. Efficient and Effective Change Principles in Active Videogames

    PubMed Central

    Fenner, Ashley A.; Howie, Erin K.; Feltz, Deborah L.; Gray, Cindy M.; Lu, Amy Shirong; Mueller, Florian “Floyd”; Simons, Monique; Barnett, Lisa M.

    2015-01-01

    Abstract Active videogames have the potential to enhance population levels of physical activity but have not been successful in achieving this aim to date. This article considers a range of principles that may be important to the design of effective and efficient active videogames from diverse discipline areas, including behavioral sciences (health behavior change, motor learning, and serious games), business production (marketing and sales), and technology engineering and design (human–computer interaction/ergonomics and flow). Both direct and indirect pathways to impact on population levels of habitual physical activity are proposed, along with the concept of a game use lifecycle. Examples of current active and sedentary electronic games are used to understand how such principles may be applied. Furthermore, limitations of the current usage of theoretical principles are discussed. A suggested list of principles for best practice in active videogame design is proposed along with suggested research ideas to inform practice to enhance physical activity. PMID:26181680

  7. Efficient and Effective Change Principles in Active Videogames.

    PubMed

    Straker, Leon M; Fenner, Ashley A; Howie, Erin K; Feltz, Deborah L; Gray, Cindy M; Lu, Amy Shirong; Mueller, Florian Floyd; Simons, Monique; Barnett, Lisa M

    2015-02-01

    Active videogames have the potential to enhance population levels of physical activity but have not been successful in achieving this aim to date. This article considers a range of principles that may be important to the design of effective and efficient active videogames from diverse discipline areas, including behavioral sciences (health behavior change, motor learning, and serious games), business production (marketing and sales), and technology engineering and design (human-computer interaction/ergonomics and flow). Both direct and indirect pathways to impact on population levels of habitual physical activity are proposed, along with the concept of a game use lifecycle. Examples of current active and sedentary electronic games are used to understand how such principles may be applied. Furthermore, limitations of the current usage of theoretical principles are discussed. A suggested list of principles for best practice in active videogame design is proposed along with suggested research ideas to inform practice to enhance physical activity. PMID:26181680

  8. Active nondestructive assay of nuclear materials: principles and applications

    SciTech Connect

    Gozani, Tsahi

    1981-01-01

    The purpose of this book is to present, coherently and comprehensively, the wealth of available but scattered information on the principles and applications of active nondestructive analysis (ANDA). Chapters are devoted to the following: background and overview; interactions of neutrons with matter; interactions of ..gamma..-rays with matter; neutron production and sources; ..gamma..-ray production and sources; effects of neutron and ..gamma..-ray transport in bulk media; signatures of neutron- and photon-induced fissions; neutron and photon detection systems and electronics; representative ANDA systems; and instrument analysis, calibration, and measurement control for ANDA. Each chapter has an introductory section describing the relationship of the topic of that chapter to ANDA. Each chapter ends with a section that summarizes the main results and conclusions of the chapter, and a reference list.

  9. Local Activity Principle:. the Cause of Complexity and Symmetry Breaking

    NASA Astrophysics Data System (ADS)

    Mainzer, Klaus

    2013-01-01

    The principle of local activity is precisely the missing concept to explain the emergence of complex patterns in a homogeneous medium. Leon O. Chua discovered and defined this principle in the theory of nonlinear electronic circuits in a mathematically rigorous way. The local principle can be generalized and proven at least for the class of nonlinear reaction-diffusion systems in physics, chemistry, biology and brain research. Recently, it was realized by memristors for nanoelectronic device applications in technical brains. In general, the emergence of complex patterns and structures is explained by symmetry breaking in homogeneous media. The principle of local activity is the cause of symmetry breaking in homogeneous media. We argue that the principle of local activity is really fundamental in science and can even be identified in quantum cosmology as symmetry breaking of local gauge symmetries generating the complexity of matter and forces in our universe. Finally, we consider applications in economic, financial, and social systems with the emergence of equilibrium states, symmetry breaking at critical points of phase transitions and risky acting at the edge of chaos. In any case, the driving causes of symmetry breaking and the emergence of complexity are locally active elements, cells, units, or agents.

  10. Adult Learning Principles in Designing Learning Activities for Teacher Development

    ERIC Educational Resources Information Center

    Gravani, Maria N.

    2012-01-01

    The research reported in this paper is an investigation of the application of adult learning principles in designing learning activities for teachers' life-long development. The exploration is illustrated by qualitative data from a case study of adult educators' and adult learners' insights and experiences of a teacher development course organised…

  11. The Didactic Principles and Their Applications in the Didactic Activity

    ERIC Educational Resources Information Center

    Marius-Costel, Esi

    2010-01-01

    The evaluation and reevaluation of the fundamental didactic principles suppose the acceptance at the level of an instructive-educative activity of a new educational paradigm. Thus, its understanding implies an assumption at a conceptual-theoretical level of some approaches where the didactic aspects find their usefulness by relating to value…

  12. Re-Presenting the Library Collections: A Story of Principles, Pathways and Partnerships

    ERIC Educational Resources Information Center

    Kattau, Maureen

    2012-01-01

    Macquarie University Library's planning for a new library coincided with a major renewal of the university's curriculum and research activity. This provided a significant opportunity to re-think the presentation of the library collections in the new environment. This article describes how strategic alignment with university goals and the framework…

  13. DESIGN CONSIDERATION INVOLVING ACTIVE SEDIMENT CAPS (PRESENTATION)

    EPA Science Inventory

    When contaminated sediments pose unacceptable risks to human health and the environment, management activities such as removal, treatment, or isolation of contaminated sediments may be required. Various capping designs are being considered for isolating contaminated sediment are...

  14. Active Power Control from Wind Power (Presentation)

    SciTech Connect

    Ela, E.; Brooks, D.

    2011-04-01

    In order to keep the electricity grid stable and the lights on, the power system relies on certain responses from its generating fleet. This presentation evaluates the potential for wind turbines and wind power plants to provide these services and assist the grid during critical times.

  15. Physics Textbooks Presentation of the Energy-Conservation Principle in Hydrodynamics

    ERIC Educational Resources Information Center

    Ibanez, M.; Ramos, M. C.

    2004-01-01

    The purpose of this study is to determine how energy-conservation principle is exposed in hydrodynamics chapters of university physics textbooks. Ten physics textbooks analyzed show considerable deficiencies in the use of energy concepts related to uncompressible fluid dynamics. The following problems have been extensively found: The pressure…

  16. Carbohydrate-active enzymes exemplify entropic principles in metabolism

    PubMed Central

    Kartal, Önder; Mahlow, Sebastian; Skupin, Alexander; Ebenhöh, Oliver

    2011-01-01

    Glycans comprise ubiquitous and essential biopolymers, which usually occur as highly diverse mixtures. The myriad different structures are generated by a limited number of carbohydrate-active enzymes (CAZymes), which are unusual in that they catalyze multiple reactions by being relatively unspecific with respect to substrate size. Existing experimental and theoretical descriptions of CAZyme-mediated reaction systems neither comprehensively explain observed action patterns nor suggest biological functions of polydisperse pools in metabolism. Here, we overcome these limitations with a novel theoretical description of this important class of biological systems in which the mixing entropy of polydisperse pools emerges as an important system variable. In vitro assays of three CAZymes essential for central carbon metabolism confirm the power of our approach to predict equilibrium distributions and non-equilibrium dynamics. A computational study of the turnover of the soluble heteroglycan pool exemplifies how entropy-driven reactions establish a metabolic buffer in vivo that attenuates fluctuations in carbohydrate availability. We argue that this interplay between energy- and entropy-driven processes represents an important regulatory design principle of metabolic systems. PMID:22027553

  17. A New "Principal Principle" (#14) of Physical Activity Education Is Emerging

    ERIC Educational Resources Information Center

    Zeigler, Earle F.

    2011-01-01

    There is every reason to believe that a new "principal principle" of physical activity education is emerging. In this article, the author talks about the new "principal principle"(#14) of physical education. Revisiting a historical milestone in the field's history to explain the origin of the term "principal principle," Dr. Arthur H. Steinhaus,…

  18. First principle active neutron coincidence counting measurements of uranium oxide

    NASA Astrophysics Data System (ADS)

    Goddard, Braden; Charlton, William; Peerani, Paolo

    2014-03-01

    Uranium is present in most nuclear fuel cycle facilities ranging from uranium mines, enrichment plants, fuel fabrication facilities, nuclear reactors, and reprocessing plants. The isotopic, chemical, and geometric composition of uranium can vary significantly between these facilities, depending on the application and type of facility. Examples of this variation are: enrichments varying from depleted (~0.2 wt% 235U) to high enriched (>20 wt% 235U); compositions consisting of U3O8, UO2, UF6, metallic, and ceramic forms; geometries ranging from plates, cans, and rods; and masses which can range from a 500 kg fuel assembly down to a few grams fuel pellet. Since 235U is a fissile material, it is routinely safeguarded in these facilities. Current techniques for quantifying the 235U mass in a sample include neutron coincidence counting. One of the main disadvantages of this technique is that it requires a known standard of representative geometry and composition for calibration, which opens up a pathway for potential erroneous declarations by the State and reduces the effectiveness of safeguards. In order to address this weakness, the authors have developed a neutron coincidence counting technique which uses the first principle point-model developed by Boehnel instead of the "known standard" method. This technique was primarily tested through simulations of 1000 g U3O8 samples using the Monte Carlo N-Particle eXtended (MCNPX) code. The results of these simulations showed good agreement between the simulated and exact 235U sample masses.

  19. Evaluation of Antileishmanial Activity of Selected Brazilian Plants and Identification of the Active Principles

    PubMed Central

    Filho, Valdir Cechinel; Meyre-Silva, Christiane; Niero, Rivaldo; Bolda Mariano, Luisa Nathália; Gomes do Nascimento, Fabiana; Vicente Farias, Ingrid; Gazoni, Vanessa Fátima; dos Santos Silva, Bruna; Giménez, Alberto; Gutierrez-Yapu, David; Salamanca, Efrain; Malheiros, Angela

    2013-01-01

    This study evaluated extracts, fractions, and isolated compounds from some selected Brazilian medicinal plants against strains of promastigotes of Leishmania amazonensis and L. brasiliensis in vitro. The cell viability was determined, comparing the results with reference standards. The dichloromethane fractions of the roots, stems, and leaves of Allamanda schottii showed IC50 values between 14.0 and 2.0 μg/mL. Plumericin was the main active compound, with IC50 of 0.3 and 0.04 μg/mL against the two species of Leishmania analyzed. The hexane extract of Eugenia umbelliflora fruits showed IC50 of 14.3 and 5.7 μg/mL against L. amazonensis and L. brasiliensis, respectively. The methanolic extracts of the seeds of Garcinia achachairu and guttiferone A presented IC50 values of 35.9 and 10.4 μg/mL, against L. amazonensis, respectively. The ethanolic extracts of the stem barks of Rapanea ferruginea and the isolated compound, myrsinoic acid B, presented activity against L. brasiliensis with IC50 of 24.1 and 6.1 μg/mL. Chloroform fraction of Solanum sisymbriifolium exhibited IC50 of 33.8 and 20.5 μg/mL, and cilistol A was the main active principle, with IC50 of 6.6 and 3.1 μg/mL against L. amazonensis and L. brasiliensis, respectively. It is concluded that the analyzed plants are promising as new and effective antiparasitic agents. PMID:23840252

  20. Evaluation of antileishmanial activity of selected brazilian plants and identification of the active principles.

    PubMed

    Filho, Valdir Cechinel; Meyre-Silva, Christiane; Niero, Rivaldo; Bolda Mariano, Luisa Nathália; Gomes do Nascimento, Fabiana; Vicente Farias, Ingrid; Gazoni, Vanessa Fátima; Dos Santos Silva, Bruna; Giménez, Alberto; Gutierrez-Yapu, David; Salamanca, Efrain; Malheiros, Angela

    2013-01-01

    This study evaluated extracts, fractions, and isolated compounds from some selected Brazilian medicinal plants against strains of promastigotes of Leishmania amazonensis and L. brasiliensis in vitro. The cell viability was determined, comparing the results with reference standards. The dichloromethane fractions of the roots, stems, and leaves of Allamanda schottii showed IC50 values between 14.0 and 2.0  μ g/mL. Plumericin was the main active compound, with IC50 of 0.3 and 0.04  μ g/mL against the two species of Leishmania analyzed. The hexane extract of Eugenia umbelliflora fruits showed IC50 of 14.3 and 5.7  μ g/mL against L. amazonensis and L. brasiliensis, respectively. The methanolic extracts of the seeds of Garcinia achachairu and guttiferone A presented IC50 values of 35.9 and 10.4  μ g/mL, against L. amazonensis, respectively. The ethanolic extracts of the stem barks of Rapanea ferruginea and the isolated compound, myrsinoic acid B, presented activity against L. brasiliensis with IC50 of 24.1 and 6.1  μ g/mL. Chloroform fraction of Solanum sisymbriifolium exhibited IC50 of 33.8 and 20.5  μ g/mL, and cilistol A was the main active principle, with IC50 of 6.6 and 3.1  μ g/mL against L. amazonensis and L. brasiliensis, respectively. It is concluded that the analyzed plants are promising as new and effective antiparasitic agents. PMID:23840252

  1. The Medical Interaction Laboratory--Multidiscipline Approach for Presentation of Principles of Physiology and Pharmacology.

    ERIC Educational Resources Information Center

    Oliver, Jack W.; Sims, Michael H.

    1979-01-01

    An interdisciplinary physiology and pharmacology course presented by the Medical Interaction Laboratory at the University of Tennessee College of Veterinary Medicine provides interaction among faculty, conserves faculty time and animal expense, and presents a coordinated laboratory experience. (BH)

  2. Nanoscale Properties and Stability Simulations of Alkali Activated Cement Phases from First Principle Calculations

    NASA Astrophysics Data System (ADS)

    Ozcelik, Ongun; White, Claire

    Using first principle density functional calculations, we present the nanoscale properties of interactions, local bonds, charge distributions, mechanical properties and strength of alkali activated cement phases which are the most promising alternative to the ordinary Portland cement with a much lower cost to the environment. We present results on the stability and long term durability of various alkali activated cement structures, effects of external alkali agents on their properties and ways of utilizing them for further applications. We compare the calculated properties of alkali activated cement with those of ordinary Portland cement and contribute to the formation of long term durability data of these phases. Comparison with X-ray and neutron scattering experiment results are also provided via pair distribution functions extracted from simulation results.

  3. Salvia officinalis for hot flushes: towards determination of mechanism of activity and active principles.

    PubMed

    Rahte, Sinikka; Evans, Richard; Eugster, Philippe J; Marcourt, Laurence; Wolfender, Jean-Luc; Kortenkamp, Andreas; Tasdemir, Deniz

    2013-06-01

    Herbal medicinal products are commonly used in alternative treatment of menopausal hot flushes. In a recent clinical study, Salvia officinalis tincture was found to reduce hot flush frequency and intensity. The aim of the current study was the investigation of the mechanism(s) responsible for the anti-hot flush activity of S. officinalis and determination of its active principle(s). The 66% ethanolic tincture, as well as the n-hexane, CHCl₃, and aqueous ethanolic subextracts obtained from the tincture were studied in vitro for two of the most relevant activities, estrogenicity and selective serotonin reuptake inhibition. Because of an increased risk of menopausal women to suffer from Alzheimer's disease, an in vitro acetylcholinesterase inhibition assay was also employed. No activity was observed in the selective serotonin reuptake inhibition or the acetylcholinesterase inhibition assays at the highest test concentrations. The tincture showed no estrogenic effects whereas the aqueous ethanolic subextract exhibited estrogenicity in the ERLUX assay with an EC₅₀ value of 64 µg/mL. Estrogenic activity-guided fractionation of the aqueous ethanolic subextract by a combination of reverse-phase vacuum liquid chromatography and gel chromatography identified luteolin-7-O-glucuronide (EC₅₀ 129 µg/mL) as the active component of the vacuum liquid chromatography fraction 4 (EC₅₀ 69 µg/mL). Luteolin-7-O-glucoside was identified as the putative estrogenic principle of the most potent minor fraction (7.6.7.6, EC₅₀ 0.7 µg/mL) obtained from the initial vacuum liquid chromatography fraction 7 (EC₅₀ 3 µg/mL). This study suggests the involvement of common and ubiquitous estrogenic flavonoids in the anti-hot flush effect of Salvia officinalis, a safe and commonly used herbal medicinal product during the menopause. PMID:23670626

  4. Comparative analysis of some active principles of herb plants by GC/MS.

    PubMed

    Gherman, C; Culea, M; Cozar, O

    2000-10-01

    A rapid extraction procedure for fingerprint chromatogram of different types of Mentha piperita L. (Labiatae family) is presented. The extracts were analysed by gas chromatography and gas chromatography-mass spectrometry (GC/MS). The main volatile compounds identified by the gas chromatography-mass spectrometric analysis of M. piperita L. were menthol, menthone, isomenthone, 1,8-cineole, menthyl acetate, limonene, beta-myrcene, carvone. M. piperita L. oil had the active principles: menthol, menthone, isomenthone, menthyl acetate, alpha-pinene, beta-pinene, champhor, limonene, linalool, piperitone. M. crispa L. showed carvone as major component. PMID:18968110

  5. 17 CFR 229.1206 - (Item 1206) Present activities.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 3 2014-04-01 2014-04-01 false (Item 1206) Present activities. 229.1206 Section 229.1206 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Gas Producing Activities § 229.1206 (Item 1206) Present activities. (a) Disclose, by geographical...

  6. 17 CFR 229.1206 - (Item 1206) Present activities.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 2 2012-04-01 2012-04-01 false (Item 1206) Present activities. 229.1206 Section 229.1206 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Gas Producing Activities § 229.1206 (Item 1206) Present activities. (a) Disclose, by geographical...

  7. 17 CFR 229.1206 - (Item 1206) Present activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 1206) Present activities. 229.1206 Section 229.1206 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Gas Producing Activities § 229.1206 (Item 1206) Present activities. (a) Disclose, by geographical...

  8. 17 CFR 229.1206 - (Item 1206) Present activities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 2 2011-04-01 2011-04-01 false (Item 1206) Present activities. 229.1206 Section 229.1206 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Gas Producing Activities § 229.1206 (Item 1206) Present activities. (a) Disclose, by geographical...

  9. 17 CFR 229.1206 - (Item 1206) Present activities.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 2 2013-04-01 2013-04-01 false (Item 1206) Present activities. 229.1206 Section 229.1206 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Gas Producing Activities § 229.1206 (Item 1206) Present activities. (a) Disclose, by geographical...

  10. In-vivo neutron activation analysis: principles and clinical applications

    SciTech Connect

    Cohn, S.H.

    1982-01-01

    In vivo neutron activation has opened a new era of both clinical diagnosis and therapy evaluation, and investigation into and modelling of body composition. The techniques are new, but it is already clear that considerable strides can be made in increasing accuracy and precision, increasing the number of elements susceptible to measurement, enhancing uniformity, and reducing the dose required for the measurement. The work presently underway will yield significant data on a variety of environmental contaminants such as Cd. Compositional studies are determining the level of vital constituents such as nitrogen and potassium in both normal subjects and in patients with a variety of metabolic disorders. Therapeutic programs can be assessed while in progress. It seems likely that by the end of this century there will have been significant progress with this research tool, and exciting insights obtained into the nature and dynamics of human body composition.

  11. Antiinflammatory effect of mace, aril of Myristica fragrans Houtt., and its active principles.

    PubMed

    Ozaki, Y; Soedigdo, S; Wattimena, Y R; Suganda, A G

    1989-02-01

    Mace which is the aril of the fruit of Myristica fragrans HOUTT, has been used in Indonesian folk medicine as aromatic stomachics, analgesics, a medicine for rheumatism, etc. The present study was carried out to elucidate the antiinflammatory effect of methanol extract obtained from Mace and its active principles. The methanol extract was extracted with ether, and then the ether soluble fraction was extracted with n-hexane. The n-hexane soluble fraction was fractionated by silica gel column chromatography (Fr-l-Fr-V), and the active principle was isolated from Fr-II by thin layer chromatography (Fr-VI-Fr-VII). The antiinflammatory activity of these fractions was investigated on carrageenin-induced edema in rats and acetic acid-induced vascular permeability in mice. All fractions and indomethacin were suspended in 2% C.M.C. solution and administered p.o. The methanol extract (1.5 g/kg), ether fraction (0.9 g/kg), n-hexane fraction (0.5 g/kg), Fr-II (0.19 g/kg) and Fr-VI (0.17 g/kg) showed a lasting antiinflammatory activity, and the potencies of these fractions were approximately the same as that of indomethacin (10 mg/kg). Fr-VI was determined to be myristicin. These results suggest that the antiinflammatory action of Mace is due to the myristicin that it contains. PMID:2487032

  12. Using Activity Theory and its Principle of Contradictions to Guide Research in Educational Technology

    ERIC Educational Resources Information Center

    Murphy, Elizabeth; Rodriguez-Manzanares, Maria A.

    2008-01-01

    This paper describes how activity theory (AT) and its principle of contradictions may be relied on to guide research in educational technology. The paper begins with a theoretical overview of AT and of its principle of contradictions. It follows with a synthesis of studies that have used AT as a lens to study information and communication…

  13. Improved solid-state NMR quantifications of active principles in pharmaceutical formulations.

    PubMed

    Sanchez, Stéphanie; Ziarelli, Fabio; Viel, Stéphane; Delaurent, Corinne; Caldarelli, Stefano

    2008-08-01

    The facility of implementation reached by solid-state nuclear magnetic resonance (ssNMR) spectroscopy makes this technique increasingly popular in pharmaceutical sciences, and more specifically for the dosage of active principles in pharmaceutical formulations, since about 80% of the formulations currently available on the market are present in the solid form. In this case, analysis by MAS NMR allows faster and simplified protocols, as a solubilization step is not required. However, the specificity of the ssNMR experiments should be explicitly taken into account when designing an accurate measurement procedure. In this work we show that, by using a combination of external concentration referencing and a properly designed sample preparation optimized for quantitative determinations, quantification of active principles in pharmaceutical formulations can be performed with both speed and precision. The method is illustrated by reinvestigating the dosage of Meprobamate, an anxiolytic agent typically prescribed in case of anxiety or muscular soreness, present in a commercial formulation (Equanil). Specifically, with respect to previously proposed analytical protocols, the procedure outlined here allows fast quantification with excellent precision. PMID:18479881

  14. Using Active Learning Strategies to Present Bloodborne Pathogen Programs

    ERIC Educational Resources Information Center

    Cooper, Leslie; Weaver, Mary G.

    2003-01-01

    Every year, school nurses have the responsibility for developing and presenting a bloodborne pathogen presentation to the education and clerical staff of their buildings. Although the information is similar from year to year, the manner in which the information is presented can be altered. Teachers are using active learning strategies in a variety…

  15. Spice active principles as the inhibitors of human platelet aggregation and thromboxane biosynthesis.

    PubMed

    Raghavendra, R H; Naidu, K Akhilender

    2009-07-01

    Spice active principles are reported to have anti-diabetic, anti-hypercholesterolemic, antilithogenic, anti-inflammatory, anti-microbial and anti-cancer properties. In our previous report we have shown that spices and their active principles inhibit 5-lipoxygenase and also formation of leukotriene C4. In this study, we report the modulatory effect of spice active principles viz., eugenol, capsaicin, piperine, quercetin, curcumin, cinnamaldehyde and allyl sulphide on in vitro human platelet aggregation. We have demonstrated that spice active principles inhibit platelet aggregation induced by different agonists, namely ADP (50microM), collagen (500microg/ml), arachidonic acid (AA) (1.0mM) and calcium ionophore A-23187 (20microM). Spice active principles showed preferential inhibition of arachidonic acid-induced platelet aggregation compared to other agonists. Among the spice active principles tested, eugenol and capsaicin are found to be most potent inhibitors of AA-induced platelet aggregation with IC50 values of 0.5 and 14.6microM, respectively. The order of potency of spice principles in inhibiting AA-induced platelet aggregation is eugenol>capsaicin>curcumin>cinnamaldehyde>piperine>allyl sulphide>quercetin. Eugenol is found to be 29-fold more potent than aspirin in inhibiting AA-induced human platelet aggregation. Eugenol and capsaicin inhibited thromboxane B2 (TXB2) formation in platelets in a dose-dependent manner challenged with AA apparently by the inhibition of the cyclooxygenase (COX-1). Eugenol-mediated inhibition of platelet aggregation is further confirmed by dose-dependent decrease in malondialdehyde (MDA) in platelets. Further, eugenol and capsaicin inhibited platelet aggregation induced by agonists-collagen, ADP and calcium ionophore but to a lesser degree compared to AA. These results clearly suggest that spice principles have beneficial effects in modulating human platelet aggregation. PMID:19501497

  16. Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles

    PubMed Central

    Spiroux de Vendômois, Joël; Séralini, Gilles-Eric

    2014-01-01

    Pesticides are used throughout the world as mixtures called formulations. They contain adjuvants, which are often kept confidential and are called inerts by the manufacturing companies, plus a declared active principle, which is usually tested alone. We tested the toxicity of 9 pesticides, comparing active principles and their formulations, on three human cell lines (HepG2, HEK293, and JEG3). Glyphosate, isoproturon, fluroxypyr, pirimicarb, imidacloprid, acetamiprid, tebuconazole, epoxiconazole, and prochloraz constitute, respectively, the active principles of 3 major herbicides, 3 insecticides, and 3 fungicides. We measured mitochondrial activities, membrane degradations, and caspases 3/7 activities. Fungicides were the most toxic from concentrations 300–600 times lower than agricultural dilutions, followed by herbicides and then insecticides, with very similar profiles in all cell types. Despite its relatively benign reputation, Roundup was among the most toxic herbicides and insecticides tested. Most importantly, 8 formulations out of 9 were up to one thousand times more toxic than their active principles. Our results challenge the relevance of the acceptable daily intake for pesticides because this norm is calculated from the toxicity of the active principle alone. Chronic tests on pesticides may not reflect relevant environmental exposures if only one ingredient of these mixtures is tested alone. PMID:24719846

  17. Interaction of microtubules with active principles of Xanthium strumarium.

    PubMed

    Menon, G S; Kuchroo, K; Dasgupta, D

    2001-01-01

    Indigenous variety of Xanthium strumarium (X. strumarium) was screened for its antimitotic activity using the microtubule-tubulin system isolated from mammalian tissue. A preliminary phytochemical screening of the whole extracts of the plant was carried out followed by partial purification of the whole extract of X.strumarium. The separated fractions obtained were identified and used for in vitro polymerization studies. The whole as well as partially separated chemical constituents of X. strumarium showed effective inhibition of tubulin polymerization. The results thus suggest that X. strumarium may possess antimitotic components. PMID:12002689

  18. Biological Activities of Phenolic Compounds Present in Virgin Olive Oil

    PubMed Central

    Cicerale, Sara; Lucas, Lisa; Keast, Russell

    2010-01-01

    The Mediterranean diet is associated with a lower incidence of atherosclerosis, cardiovascular disease, neurodegenerative diseases and certain types of cancer. The apparent health benefits have been partially ascribed to the dietary consumption of virgin olive oil by Mediterranean populations. Much research has focused on the biologically active phenolic compounds naturally present in virgin olive oils to aid in explaining reduced mortality and morbidity experienced by people consuming a traditional Mediterranean diet. Studies (human, animal, in vivo and in vitro) have demonstrated that olive oil phenolic compounds have positive effects on certain physiological parameters, such as plasma lipoproteins, oxidative damage, inflammatory markers, platelet and cellular function, antimicrobial activity and bone health. This paper summarizes current knowledge on the bioavailability and biological activities of olive oil phenolic compounds. PMID:20386648

  19. Ascaridole as a pharmacologically active principle of "Paico," a medicinal Peruvian plant.

    PubMed

    Okuyama, E; Umeyama, K; Saito, Y; Yamazaki, M; Satake, M

    1993-07-01

    "Paico," Chenopodium ambrosioides L., is a traditional Peruvian medicine which is considered to be nervine, antirheumatic, anthelmintic, etc. An attempt was made to isolate the component having sedative and/or analgesic properties from "Paico" and "Aritasou" (the Japanese name for C. ambrosioides). Ascaridole was identified as the active principle in both materials. PMID:8374999

  20. Scaffolded Active Learning: Nine Pedagogical Principles for Building a Modern Veterinary Curriculum.

    PubMed

    May, Stephen A; Silva-Fletcher, Ayona

    2015-01-01

    Veterinary discipline experts unfamiliar with the broader educational literature can find the adoption of an evidence-based approach to curriculum development challenging. However, greater societal and professional demands for achieving and verifying Day One knowledge and skills, together with continued progress in information generation and technology, make it all the more important that the defined period for initial professional training be well used. This article presents and discusses nine pedagogical principles that have been used in modern curricular development in Australia, the United Kingdom, and the United States: (1) outcomes-based curriculum design; (2) valid and reliable assessments; (3) active learning; (4) integrated knowledge for action; (5) tightly controlled core curriculum; (6) "just-in-time" rather than "just-in-case" knowledge; (7) vertical integration, the spiral curriculum, and sequential skills development; (8) learning skills support; and (9) bridges from classroom to workplace. Crucial to effective educational progress is active learning that embraces the skills required by the modern professional, made possible by tight control of curricular content. In this information age, professionals' ability to source information on a "just-in-time" basis to support high quality reasoning and decision making is far more important than the memorization of large bodies of increasingly redundant information on a "just-in-case" basis. It is important that those with responsibility for veterinary curriculum design ensure that their programs fully equip the modern veterinary professional for confident entry into the variety of roles in which society needs their skills. PMID:26421513

  1. Ethoxylated adjuvants of glyphosate-based herbicides are active principles of human cell toxicity.

    PubMed

    Mesnage, R; Bernay, B; Séralini, G-E

    2013-11-16

    Pesticides are always used in formulations as mixtures of an active principle with adjuvants. Glyphosate, the active ingredient of the major pesticide in the world, is an herbicide supposed to be specific on plant metabolism. Its adjuvants are generally considered as inert diluents. Since side effects for all these compounds have been claimed, we studied potential active principles for toxicity on human cells for 9 glyphosate-based formulations. For this we detailed their compositions and toxicities, and as controls we used a major adjuvant (the polyethoxylated tallowamine POE-15), glyphosate alone, and a total formulation without glyphosate. This was performed after 24h exposures on hepatic (HepG2), embryonic (HEK293) and placental (JEG3) cell lines. We measured mitochondrial activities, membrane degradations, and caspases 3/7 activities. The compositions in adjuvants were analyzed by mass spectrometry. Here we demonstrate that all formulations are more toxic than glyphosate, and we separated experimentally three groups of formulations differentially toxic according to their concentrations in ethoxylated adjuvants. Among them, POE-15 clearly appears to be the most toxic principle against human cells, even if others are not excluded. It begins to be active with negative dose-dependent effects on cellular respiration and membrane integrity between 1 and 3ppm, at environmental/occupational doses. We demonstrate in addition that POE-15 induces necrosis when its first micellization process occurs, by contrast to glyphosate which is known to promote endocrine disrupting effects after entering cells. Altogether, these results challenge the establishment of guidance values such as the acceptable daily intake of glyphosate, when these are mostly based on a long term in vivo test of glyphosate alone. Since pesticides are always used with adjuvants that could change their toxicity, the necessity to assess their whole formulations as mixtures becomes obvious. This challenges

  2. Geothermal activity in Italy: present status and future prospects

    SciTech Connect

    Carella, R.; Palmerini, C.G.; Stefani, G.C.; Verdiani, G.

    1985-01-01

    In the Italian Peninsula the Apennines separate a relatively cold Po-Adriatic-Ionian ''foredeep'' external belt from a warmer Tyrrhenian ''back-arc'' internal tensional belt. The latter i characterized by high geothermal heat flow together with conspicuous recent or present-day volcani phenomena. In this area, extending from Tuscany to Campania, lie the known steam- and waterdominated fields. Other ''warm'' areas are located on some Tyrrhenian islands. Within the ''cold'' external belt, interesting locations for low enthalpy utilizations can be found in the Po river valley, particularly in the eastern part near Ferrara and Abano. Since 1977 ENEL (National Electri Energy Agency) and AGIP (State Oil Company) have been jointly conducting geothermal activities in Italy, with the exception of the Tuscan geothermal area where ENEL operates on an exclusive basis. At present the areas surveyed cover about 8250 kmS. As of December 1983 the geothermal installed capacity was 456.2 MW (net capacity 340 MW) and low-temperature geothermal resources equivalent to 100,000 OET /yr were being used. The National Energy Plant (PEN), issued on 4 December 1981, forecast for the year 1990 a geothermal power increment of 200 MW /SUB e/ above the 449.1 MW /SUB e/ already installed. The target in the low enthalpy non-electric sector is to save 300,000 OET/yr by 1990. This paper describes the activities carried out from March 1975 to December 1983 and the main projects in progress.

  3. Activation of cells using femtosecond laser beam (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Batabyal, Subrata; Satpathy, Sarmishtha; Kim, Young-tae; Mohanty, Samarendra K.

    2016-03-01

    Study of communication in cellular systems requires precise activation of targeted cell(s) in the network. In contrast to chemical, electrical, thermal, mechanical stimulation, optical stimulation is non-invasive and is better suited for stimulation of targeted cells. As compared to visible lasers, the near infrared (NIR) microsecond/nanosecond pulsed laser beams are being used as preferred stimulation tool as they provide higher penetration depth in tissues. Femotosecond (FS) laser beams in NIR are also being used for direct and indirect (i.e. via two-photon optogenetics) stimulation of cells. Here, we present a comparative evaluation of efficacy of NIR FS laser beam for direct (no optogenetic sensitization) and 2ph optogenetic stimulation of cells. Further, for the first time, we demonstrate the use of blue (~450 nm, obtained by second harmonic generation) FS laser beam for stimulation of cells with and without Channelrhodopisn-2 (ChR2) expression. Comparative analysis of photocurrent generated by blue FS laser beam and continuous wave blue light for optogenetics stimulation of ChR2 transfected HEK cells will be presented. The use of ultrafast laser micro-beam for focal, non-contact, and repeated stimulation of single cells in a cellular circuitry allowed us to study the communication between different cell types.

  4. A. A. Ukhtomskii`s dominance principle of brain activity in the perception of electromagnetic fields

    SciTech Connect

    Kholodov, Yu.A.

    1994-07-01

    Preliminary instruction of the subject plays an important role in the perception of weak electromagnetic fields acting on the hand. Active attention to a potential effect amplifies a brain state that can be called caution dominance and arises spontaneously with a {open_quotes}placebo{close_quotes} or an electromagnetic field. The radar principle of brain operation is discussed among the physiological mechanisms through which electromagnetic fields act on an organism.

  5. A. A. Ukhtomskii's dominance principle of brain activity in the perception of electromagnetic fields

    NASA Astrophysics Data System (ADS)

    Kholodov, Yu. A.

    1994-01-01

    Preliminary instruction of the subject plays an important role in the perception of weak electromagnetic fields acting on the hand. Active attention to a potential effect amplifies a brain state that can be called caution dominance and arises spontaneously with a “placebo” or an electromagnetic field. The radar principle of brain operation is discussed among the physiological mechanisms through which electromagnetic fields act on an organism.

  6. In vivo anthelmintic activity of Carex baccans and its active principle resveratrol against Hymenolepis diminuta.

    PubMed

    Giri, Bikash Ranjan; Bharti, Ravi Rao; Roy, Bishnupada

    2015-02-01

    Anthelmintic resistance against most of the commercial drugs is a great threat to humans as well as the veterinary live stocks. Hence, new treatment strategies to control helminth infections are essential at this hour. Carex baccans Nees has been traditionally used by Jaintia tribes in Northeast India to get rid of intestinal worm infections. Therefore, the present study was conducted to evaluate in vivo cestocidal activity of root tuber extract of C. baccans and its active component resveratrol against the zoonotic cestode Hymenolepis diminuta in the experimental model rat. The cestocidal activity was determined by monitoring the eggs per gram (EPG) counts in faeces of different treated groups. The result showed that the highest dose of the plant extract (50 mg/kg) and resveratrol (4.564 mg/kg body weight) has significant anthelmintic efficacy against H. diminuta. Crude extract of the plant as well as resveratrol reduced EPG count (56.012 and 46.049 %) and also resulted in decreased worm burden by 44.287 and 31.034 %, respectively. The efficacy of the crude extract and resveratrol can be compared to the reference drug praziquantel. The results exhibits considerable cestocidal potential of root tuber crude extract of C. baccans and resveratrol and justify its folklore use. PMID:25585605

  7. Present Day Activity of South Polar Gullies on Mars

    NASA Astrophysics Data System (ADS)

    Raack, J.; Reiss, D.; Ruesch, O.; Hiesinger, H.

    2012-04-01

    Here we report on clearly identified seasonal changes of gullies observed within the last two martian years (MY) on slopes of a south polar pit, which is located in a filled crater (diameter ~54 km) north of Sisyphi Cavi at ~68.5°S and ~1.5°E. Using new high-resolution imaging (High Resolution Imaging Science Experiment, HiRISE), temperature (Thermal Emission Spectrometer, TES) and spectral data (Compact Reconnaissance Imaging Spectrometer for Mars, CRISM; Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité, OMEGA), we analyzed the exact timing of changes of gullies and detect the possible medium (CO2, H2O or dry) and mechanism which initiate present day gully activity. Two locations in the study region with clear modifications of gullies were identified in MY 29 between LS 226° and LS 247° and between LS 209° and LS 247°. In MY 30 changes occur in both locations between LS 218° and LS 249°. Modifications are the formation of a new small apron and new deposits within the channel, both associated with the deposition of dark material. Erosion in gully alcoves or channels was not observed. TES data show temperatures between ~180 and ~240 K within the period of gully modifications. Maximum temperatures in the region rise up to ~285 K between LS ~270° and ~310°. Spectral data show a CO2-cover of the study region until LS 227°. CO2-ice free surface are spectrally observed for the first time at LS 249°. H2O was not spectrally detected in the study region and a mixture of CO2 and H2O as presented in [1] cannot be clearly detected. Unfortunately, there are no spectral data available between LS 227° and 249°. Modifications of gullies imply seasonal volatile activity. The activity can be narrowed down to occur between LS 226° and 247° at mean temperatures between ~180 and ~240 K. This is in the range of temperatures where CO2 sublimates back into the atmosphere. Based on the temperature range, the most likely candidate for the observed new

  8. Photovoltaic Reliability Group activities in USA and Brazil (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Dhere, Neelkanth G.; Cruz, Leila R. O.

    2015-09-01

    Recently prices of photovoltaic (PV) systems have been reduced considerably and may continue to be reduced making them attractive. If these systems provide electricity over the stipulated warranty period, it would be possible attain socket parity within the next few years. Current photovoltaic module qualifications tests help in minimizing infant mortality but do not guarantee useful lifetime over the warranty period. The PV Module Quality Assurance Task Force (PVQAT) is trying to formulate accelerated tests that will be useful towards achieving the ultimate goal of assuring useful lifetime over the warranty period as well as to assure manufacturing quality. Unfortunately, assuring the manufacturing quality may require 24/7 presence. Alternatively, collecting data on the performance of fielded systems would assist in assuring manufacturing quality. Here PV systems installed by home-owners and small businesses can constitute as an important untapped source of data. The volunteer group, PV - Reliable, Safe and Sustainable Quality! (PVRessQ!) is providing valuable service to small PV system owners. Photovoltaic Reliability Group (PVRG) is initiating activities in USA and Brazil to assist home owners and small businesses in monitoring photovoltaic (PV) module performance and enforcing warranty. It will work in collaboration with small PV system owners, consumer protection agencies. Brazil is endowed with excellent solar irradiance making it attractive for installation of PV systems. Participating owners of small PV systems would instruct inverter manufacturers to copy the daily e-mails to PVRG and as necessary, will authorize the PVRG to carry out review of PV systems. The presentation will consist of overall activities of PVRG in USA and Brazil.

  9. A Cu-amyloid β complex activating Fenton chemistry in Alzheimer's disease: Learning with multiple first-principles simulations

    NASA Astrophysics Data System (ADS)

    La Penna, Giovanni; Hureau, Christelle; Faller, Peter

    2014-10-01

    Amyloid β peptides form complexes with copper, both in vitro and in vivo, relatively soluble in water as oligomers and active as catalysts for oxidation of organic substrates by hydrogen peroxide, a species always present in cells and in their aerobic environment. All these species are present in the synapse, thus making a connection between the amyloid cascade hypothesis and the oxidative damages by reactive oxygen species in neurons, when pathological dishomeostasis of amyloid peptides and metal ions occur. In order to understand the structural features of these toxic complexes, we built several models of Cu-Aβ peptides in monomeric and dimeric forms and we found, performing multiple first-principles molecular dynamics simulations, that Cu-induced dimers are more active than monomers in converting hydrogen peroxide into aggressive hydroxyl radicals.

  10. Scale-free brain activity: past, present and future

    PubMed Central

    He, Biyu J.

    2014-01-01

    Brain activity observed at many spatiotemporal scales exhibits a 1/f-like power spectrum, including neuronal membrane potentials, neural field potentials, noninvasive electroencephalography, magnetoencephalography and functional magnetic resonance imaging signals. A 1/f-like power spectrum is indicative of arrhythmic brain activity that does not contain a predominant temporal scale (hence, “scale-free”). This characteristic of scale-free brain activity distinguishes it from brain oscillations. While scale-free brain activity and brain oscillations coexist, our understanding of the former remains very limited. Recent research has shed light on the spatiotemporal organization, functional significance and potential generative mechanisms of scale-free brain activity, as well as its developmental and clinical relevance. A deeper understanding of this prevalent brain signal should provide new insights and analytical tools for cognitive neuroscience. PMID:24788139

  11. Fractions of aqueous and methanolic extracts from tomato (Solanum lycopersicum L.) present platelet antiaggregant activity.

    PubMed

    Fuentes, Eduado J; Astudillo, Luis A; Gutiérrez, Margarita I; Contreras, Samuel O; Bustamante, Luis O; Rubio, Pia I; Moore-Carrasco, Rodrigo; Alarcón, Marcelo A; Fuentes, Jaime A; González, Daniel E; Palomo, Iván F

    2012-03-01

    Cardiovascular disease (CVD) is the leading cause of death worldwide. Its prevention emphasizes three aspects: not smoking, physical activity and a healthy diet. Recently, we screened the antithrombotic activity of a selected group of fruits and vegetables. Among them, tomato showed an important effect. The aim of this study was to evaluate and characterize the platelet antiaggregatory activity of tomato (Solanum lycopersicum L.). For this, we obtained aqueous and methanolic tomato extracts and evaluated the effect of pH (2 and 10) and temperature (22, 60 and 100°C) on this activity. Furthermore, in order to isolate the antiaggregant principle, we separated tomato extracts into several fractions (A-D) by size exclusion chromatography. In addition, we evaluated the platelet antiaggregating activity ex vivo in Wistar rats. Aqueous and methanolic extracts of tomato treated at 22, 60 and 100°C and pH 2 and 10 still inhibited platelet aggregation (in vitro). Moreover, it was noted that one of the fractions (fraction C), from both aqueous and methanolic extracts, presented the highest activity (∼70% inhibition of platelet aggregation) and concentration dependently inhibited platelet aggregation significantly compared with control (P < 0.05). These fractions did not contain lycopene but presented two peaks of absorption, at 210 and 261 nm, compatible with the presence of nucleosides. In rats treated with tomato macerates, a mild platelet antiaggregating effect ex vivo was observed. Further studies are required to identify the molecules with platelet antiaggregating activity and antiplatelet mechanisms of action. PMID:22185934

  12. Supporting Teachers in Designing CSCL Activities: A Case Study of Principle-Based Pedagogical Patterns in Networked Second Language Classrooms

    ERIC Educational Resources Information Center

    Wen, Yun; Looi, Chee-Kit; Chen, Wenli

    2012-01-01

    This paper proposes the identification and use of principle-based pedagogical patterns to help teachers to translate design principles into actionable teaching activities, and to scaffold student learning with sufficient flexibility and creativity. A set of pedagogical patterns for networked Second language (L2) learning, categorized and…

  13. Capillary electrophoretic and extraction conditions for the analysis of Catha edulis FORKS active principles.

    PubMed

    Roda, Gabriella; Liberti, Vincenzo; Arnoldi, Sebastiano; Argo, Antonella; Rusconi, Chiara; Suardi, Sonia; Gambaro, Veniero

    2013-05-10

    A capillary electrophoretic method, which allowed the detection and separation of the active principles of Catha edulis, i.e. cathinone, cathine and phenylpropanolamine, was developed. A suitable internal standard (nicotinamide), which permitted the quantification of the analytes reducing the variability of the migration times due to EOF changes, was identified. The analytical method was validated, assessing linearity, sensitivity and repeatability, showing optimal features for the analysis of the vegetable material. Moreover extraction conditions were investigated to achieve the exhaustion of the plant material in the fastest and most efficient way to meet the requirements of the Court. PMID:23597752

  14. Contralateral delay activity tracks the influence of Gestalt grouping principles on active visual working memory representations.

    PubMed

    Peterson, Dwight J; Gözenman, Filiz; Arciniega, Hector; Berryhill, Marian E

    2015-10-01

    Recent studies have demonstrated that factors influencing perception, such as Gestalt grouping cues, can influence the storage of information in visual working memory (VWM). In some cases, stationary cues, such as stimulus similarity, lead to superior VWM performance. However, the neural correlates underlying these benefits to VWM performance remain unclear. One neural index, the contralateral delay activity (CDA), is an event-related potential that shows increased amplitude according to the number of items held in VWM and asymptotes at an individual's VWM capacity limit. Here, we applied the CDA to determine whether previously reported behavioral benefits supplied by similarity, proximity, and uniform connectedness were reflected as a neural savings such that the CDA amplitude was reduced when these cues were present. We implemented VWM change-detection tasks with arrays including similarity and proximity (Experiment 1); uniform connectedness (Experiments 2a and 2b); and similarity/proximity and uniform connectedness (Experiment 3). The results indicated that when there was a behavioral benefit to VWM, this was echoed by a reduction in CDA amplitude, which suggests more efficient processing. However, not all perceptual grouping cues provided a VWM benefit in the same measure (e.g., accuracy) or of the same magnitude. We also found unexpected interactions between cues. We observed a mixed bag of effects, suggesting that these powerful perceptual grouping benefits are not as predictable in VWM. The current findings indicate that when grouping cues produce behavioral benefits, there is a parallel reduction in the neural resources required to maintain grouped items within VWM. PMID:26018644

  15. Physical activity: the present in the context of the past.

    PubMed

    Malina, Robert M; Little, Bertis B

    2008-01-01

    In the broad sense, modern humans have lived in an environment in which physical activity and associated movement skills were central, especially in the context of physical competition with other animals. The physically active lifestyle of earlier human populations has been emphasized, especially the cardiovascular endurance component and energy expenditure, but less attention has been devoted to the gross and fine motor skills that are essential components of this lifestyle. Motor skills developed through practice are important determinants of success and survival in preindustrial societies. In industrial and postindustrial societies, on the other hand, the role of physical activity is different, with prowess in certain areas of physical expertise (e.g., accuracy with projectiles, muscular strength, among others) and prolonged exertion (i.e., cardiovascular endurance) less important for survival. The combined effects of the transition to a sedentary lifestyle and attendant dietary changes have resulted first an epidemic of coronary heart disease and more recently an epidemic of overweight/obesity in postindustrial societies. Although mortality associated with coronary heart disease has declined, due largely to biomedical advances, overweight and obesity have increased concomitantly with population reduction in physical activity (energy expenditure) and increased calorie (energy) consumption. The current scenario begs several questions which have implications for contemporary human biology related to sustaining the pace of cultural change on a biological base that is increasingly being compromised by physical inactivity, overweight, and obesity. PMID:18433002

  16. Activated Brain Endothelial Cells Cross-Present Malaria Antigen

    PubMed Central

    Howland, Shanshan W.; Poh, Chek Meng; Rénia, Laurent

    2015-01-01

    In the murine model of cerebral malaria caused by P. berghei ANKA (PbA), parasite-specific CD8+ T cells directly induce pathology and have long been hypothesized to kill brain endothelial cells that have internalized PbA antigen. We previously reported that brain microvessel fragments from infected mice cross-present PbA epitopes, using reporter cells transduced with epitope-specific T cell receptors. Here, we confirm that endothelial cells are the population responsible for cross-presentation in vivo, not pericytes or microglia. PbA antigen cross-presentation by primary brain endothelial cells in vitro confers susceptibility to killing by CD8+ T cells from infected mice. IFNγ stimulation is required for brain endothelial cross-presentation in vivo and in vitro, which occurs by a proteasome- and TAP-dependent mechanism. Parasite strains that do not induce cerebral malaria were phagocytosed and cross-presented less efficiently than PbA in vitro. The main source of antigen appears to be free merozoites, which were avidly phagocytosed. A human brain endothelial cell line also phagocytosed P. falciparum merozoites. Besides being the first demonstration of cross-presentation by brain endothelial cells, our results suggest that interfering with merozoite phagocytosis or antigen processing may be effective strategies for cerebral malaria intervention. PMID:26046849

  17. Quantitative phase imaging technologies to assess neuronal activity (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Thouvenin, Olivier; Fink, Mathias; Boccara, Claude

    2016-03-01

    Active neurons tends to have a different dynamical behavior compared to resting ones. Non-exhaustively, vesicular transport towards the synapses is increased, since axonal growth becomes slower. Previous studies also reported small phase variations occurring simultaneously with the action potential. Such changes exhibit times scales ranging from milliseconds to several seconds on spatial scales smaller than the optical diffraction limit. Therefore, QPI systems are of particular interest to measure neuronal activity without labels. Here, we report the development of two new QPI systems that should enable the detection of such activity. Both systems can acquire full field phase images with a sub nanometer sensitivity at a few hundreds of frames per second. The first setup is a synchronous combination of Full Field Optical Coherence Tomography (FF-OCT) and Fluorescence wide field imaging. The latter modality enables the measurement of neurons electrical activity using calcium indicators. In cultures, FF-OCT exhibits similar features to Digital Holographic Microscopy (DHM), except from complex computational reconstruction. However, FF-OCT is of particular interest in order to measure phase variations in tissues. The second setup is based on a Quantitative Differential Interference Contrast setup mounted in an epi-illumination configuration with a spectrally incoherent illumination. Such a common path interferometer exhibits a very good mechanical stability, and thus enables the measurement of phase images during hours. Additionally, such setup can not only measure a height change, but also an optical index change for both polarization. Hence, one can measure simultaneously a phase change and a birefringence change.

  18. Activities at Fermilab related to collider present and future

    NASA Astrophysics Data System (ADS)

    Goderre, G. P.; Holt, J.

    1992-11-01

    The long-range Fermilab program requires fully capitalizing on the world's highest energy accelerator, the Tevatron, throughout the decade of the 90's. The program calls for increasing the collider luminosity with each successive run until peak luminosities of ≳5×1031 cm-2 s-1 and integrated luminosities of ≳100 pb-1 per run are achieved, effectively doubling the mass range accessible for discovery. If the quark lies at the upper range of the mass of the Tevatron, then increasing the energy of the collider operation could prove to be a crucial factor in the future program as well. In order to achieve these goals, we present a highly challenging upgrade of the present accelerator complex, called Fermilab III. In order to increase this performance level by a factor of 50, many changes are needed. Such a plan, of necessity, has modifications in almost all areas of the accelerator as the present system is reasonably optimized. (AIP)

  19. Antihyperlipidemic effect of active principle isolated from seed of Eugenia jambolana on alloxan-induced diabetic rabbits.

    PubMed

    Sharma, Suman B; Tanwar, Reenu S; Nasir, Afreena; Prabhu, Krishna M

    2011-04-01

    Diabetes is accompanied by lipid abnormalities, which contribute significantly to cardiovascular morbidity and mortality in diabetic patients. We previously demonstrated the potent antihyperglycemic activity of the active principle (fraction II from Sephadex LH 20 chromatography [LH II]) isolated from ethanolic seed extract of Eugenia jambolana in diabetic rabbits. In the present study, the efficacy of LH II was evaluated for its hypolipidemic activity in alloxan-induced mildly diabetic (MD) and severely diabetic (SD) rabbits. Phytochemical investigation of LH II by various structural spectra showed the presence of saturated fatty acid, Δ(5) lipid, and sterol. Oral administration of LH II (10 mg/kg of body weight) for 21 days resulted in improved glycemic control in both MD and SD rabbits. After treatment with LH II, serum total cholesterol, triglycerides, high-density lipoprotein cholesterol, and the total cholesterol/high-density lipoprotein cholesterol ratio were significantly improved. LH II also resulted in significant (P < .001) improvement in 3-hydroxy-3-methylglutaryl-coenzyme A reductase activity and levels of total lipids and glycogen in both MD and SD rabbits. Thus, the present study demonstrates that LH II possesses potent hypolipidemic activity and efficacy in both MD and SD rabbits. PMID:21370965

  20. Present status of clinical deployment of glucokinase activators.

    PubMed

    Nakamura, Akinobu; Terauchi, Yasuo

    2015-03-01

    Glucokinase is one of four members of the hexokinase family of enzymes. Its expression is limited to the major organs (such as the pancreas, liver, brain and the gastrointestinal tract) that are thought to have an integrated role in glucose sensing. In the liver, phosphorylation of glucose by glucokinase promotes glycogen synthesis, whereas in the β-cells, it results in insulin release. Studies of glucokinase-linked genetically-modified mice and mutations in humans have illustrated the important roles played by glucokinase in whole-body glucose homeostasis, and suggest that the use of pharmacological agents that augment glucokinase activity could represent a viable treatment strategy in patients with type 2 diabetes. Since 2003, many glucokinase activators (GKAs) have been developed, and their ability to lower the blood glucose has been shown in several animal models of type 2 diabetes. Also, we and others have shown in mouse models that GKAs also have the effect of stimulating the proliferation of β-cells. However, the results of recent phase II trials have shown that GKAs lose their efficacy within several months of use, and that their use is associated with a high incidence of hypoglycemia; furthermore, patients treated with GKAs frequently developed dyslipidemia. A better understanding of the role of glucokinase in metabolic effects is required to resolve several issues identified in clinical trials. PMID:25802718

  1. Diterpene resin acids: Major active principles in tall oil against Variegated cutworm,Peridroma saucia (Lepidoptera: Noctuidae).

    PubMed

    Xie, Y; Isman, M B; Feng, Y; Wong, A

    1993-06-01

    Tall oil, a by-product of the kraft process for pulping softwood, has been shown to have insecticidal properties. In the present study, the active principles in tall oil against the variegated cutworm,Peridroma saucia Hübner, were investigated. GC-MS analysis showed that abietic, dehydroabietic, and isopimaric acids were major resin acid components of crude tall oil and depitched tall oil. When crude tall oil samples of differing resin acid composition were incorporated into artificial diet at a concentration of 2.0% fresh weight, they suppressed larval growth by 45-60% compared to controls. This suppression was significantly (P≤0.05) correlated with the equivalent contents of abietic, dehydroabietic, isopimaric, and total resin acids. These results were also evident from a diet choice test, showing that the second-instar larvae obviously selected diets with low levels of resin acids when different diets were randomly arranged in a Petri dish. Bioassays with pure resin acids (abietic, dehydroabietic, and isopimaric acids) demonstrated that all individual chemicals have similar bioactivity against this insect. Comparison of the bioactivities of depitched tall oil and an equivalent mixture of pure resin acids in thePeridroma chronic growth bioassay indicated that pure resin acids and depitched tall oil share a common mode of action to this insect. This study confirms that resin acids are major active principles in tall oil against the variegated cutworm, but other chemicals likely also contribute to the bioactivity of tall oil. PMID:24249127

  2. [Ethical and legal principles for the activities of bioprospection in relation to human beings and the human genome].

    PubMed

    Romeo Casabona, Carlos María

    2012-01-01

    During recent decades, bioprospecting has become an important field of research, which looks for development alternatives, entry into global (environmental) markets, and the subsequent obtention of benefits under sustainable development principles. However, there is still so much to discuss regarding the social and environmental impacts produced by this activity, as well as its main limitations. To this end, the Forum/round-table discussion, entitled "Bioprospección, Etica y Sociedad" was organised to take place on 28 March 2012 at the National University of Colombia. Its main objective was to enrich our knowledge on bioprospecting considering the ethical considerations that involve society. The presentation given by Professor ROMEO CASABONA, regarding the connection between bioprospecting and the human genome deserves special attention and is presented below. PMID:23115822

  3. The Non-Discrimination Principle and American Higher Education: Judicial Failure to Recognize the Present Effects of Past Discrimination

    ERIC Educational Resources Information Center

    Bickel, Robert D.

    2008-01-01

    This article suggests that any approach to the issue of access to higher education in the United Kingdom not view the approach of the United States in the recent University of Michigan cases as providing appropriate guidance. It is the author's assertion that the United States Supreme Court has failed to recognize the present effects of a long…

  4. Principled Narrative

    ERIC Educational Resources Information Center

    MacBeath, John; Swaffield, Sue; Frost, David

    2009-01-01

    This article provides an overview of the "Carpe Vitam: Leadership for Learning" project, accounting for its provenance and purposes, before focusing on the principles for practice that constitute an important part of the project's legacy. These principles framed the dialogic process that was a dominant feature of the project and are presented,…

  5. Union activity in hospitals: past, present, and future.

    PubMed

    Becker, E R; Sloan, F A; Steinwald, B

    1982-06-01

    Between 1970 and 1980, the percentage of hospitals with one or more collective bargaining contracts increased from 15.7 percent to 27.4 percent. A substantial amount of variation exists in the extent of unionism on the basis of hospital ownership, bed size, and location. Employees are more likely to organize when hospitals in the State are regulated by a mandatory rate-setting program. Unions raise hospital employee's wages--a modal estimate for RNs is about 6 percent; the corresponding figure for nonprofessional employees is about 10 percent. Growth of union activity in hospitals has generally not been a major contributor to hospital wage inflation, and less than 10 percent of the increase in real (relative to the Consumer Price Index) spending for hospital care that occurred during the 1970s can be attributed to union growth. We project that between 45 and 50 percent of all hospitals will have at least one union by 1990. PMID:10309636

  6. Union Activity in Hospitals: Past, Present, and Future

    PubMed Central

    Becker, Edmund R.; Sloan, Frank A.; Steinwald, Bruce

    1982-01-01

    Between 1970 and 1980, the percentage of hospitals with one or more collective bargaining contracts increased from 15.7 percent to 27.4 percent. A substantial amount of variation exists in the extent of unionism on the basis of hospital ownership, bed size, and location. Employees are more likely to organize when hospitals in the State are regulated by a mandatory rate-setting program. Unions raise hospital employee's wages—a modal estimate for RNs is about 6 percent; the corresponding figure for nonprofessional employees is about 10 percent. Growth of union activity in hospitals has generally not been a major contributor to hospital wage inflation, and less than 10 percent of the increase in real (relative to the Consumer Price Index) spending for hospital care that occurred during the 1970s can be attributed to union growth. We project that between 45 and 50 percent of all hospitals will have at least one union by 1990. PMID:10309636

  7. Interfering with mineralocorticoid receptor activation: the past, present, and future

    PubMed Central

    2014-01-01

    Aldosterone is a potent mineralocorticoid produced by the adrenal gland. Aldosterone binds to and activates the mineralocorticoid receptor (MR) in a plethora of tissues, but the cardiovascular actions of aldosterone are of primary interest clinically. Although MR antagonists were developed as antihypertensive agents, they are now considered to be important therapeutic options for patients with heart failure. Specifically, blocking only the MR has proven to be a difficult task because of its similarity to other steroid receptors, including the androgen and progesterone receptors. This lack of specificity caused the use of the first-generation mineralocorticoid receptor antagonists to be fraught with difficulty because of the side effects produced by drug administration. However, in recent years, several advances have been made that could potentially increase the clinical use of agents that inhibit the actions of aldosterone. These will be discussed here along with some examples of the beneficial effects of these new therapeutic agents. PMID:25165560

  8. Determination of antioxidant activity of spices and their active principles by differential pulse voltammetry.

    PubMed

    Palma, Alberto; Ruiz Montoya, Mercedes; Arteaga, Jesús F; Rodríguez Mellado, Jose M

    2014-01-22

    The anodic oxidation of mercury in the presence of hydrogen peroxide in differential pulse voltammetry (DPV) was used to determine the antioxidant (AO) character of radical scavengers. Hydroperoxide radical is formed at the potentials of the oxidation peak on mercury electrodes, such radical reacting with the antioxidants in different extension. The parameter C10 (antioxidant concentration at which the peak area decreases by 10%) is used to measure the scavenging activity of the individual antioxidants. To establish the scavenging activity of antioxidant mixtures as a whole, the parameter, μ10 as the reverse of V10, V10 being the volume necessary to decrease the peak area in DPV by 10%, was selected. Higher μ10 values correspond to higher scavenging activity. The studies have been extended to aqueous extracts of some species. The results may be useful in explaining the effect of spices in vitro and in vivo studies. PMID:25264569

  9. Present status of some technological activities supporting the MOLCARE project

    SciTech Connect

    Torazza, A.; Rocchini, G.; Scagliotti, M.

    1996-12-31

    The development of MCFC stack technology is carried out at Ansaldo Ricerche in the framework of the MOLCARE project, a cooperation with Spanish companies under a partial UE funding, while a specific research program concerning the physico-chemical characterization of materials is performed jointly by CISE and ENEL. The project includes the development, the construction and the testing of a full scale 100 kW prototype, the assessment of stack technology on subscale stacks, the mathematical modelling of the MCFC based plants and the basic researches. The aim of the basic researches, carried out on single cells, is to improve the effectiveness and durability of both the active and the hardware materials. The Ansaldo stack technology is based on external manifolding. The full scale 100 kW prototype will be integrated with the sensible heat reformer and other ancillary equipments according to the {open_quote}Compact Unit (CU){close_quotes} concept. These technical choices stress requirements for manifold gasket configuration. electrolyte migration control, {Delta}p management and porous component compaction.

  10. Forecasting the Peak of the Present Solar Activity Cycle

    NASA Astrophysics Data System (ADS)

    Hamid, Rabab; Marzouk, Beshir

    2016-07-01

    Solar forecasting of the level of sun Activity is very important subject for all space programs. Most predictions are based on the physical conditions prevailing at or before the solar cycle minimum preceding the maximum in question. Our aim is to predict the maximum peak of cycle 24 using precursor techniques in particular those using spotless event, geomagnetic aa min. index and solar flux F10.7. Also prediction of exact date of the maximum (Tr) is taken in consideration. A study of variation over previous spotless event for cycles 7-23 and that for even cycles (8-22) are carried out for the prediction. Linear correlation between RM and spotless event around the preceding minimum gives RM24t = 101.9with rise time Tr = 4.5 Y. For the even cycles RM24e = 108.3 with rise time Tr = 3.9 Y. Based on the average aa min. index for the year of sunspot minimum cycles (13 - 23), we estimate the expected amplitude for cycle 24 to be RMaa = 116.5 for both the total and even cycles. Application of the data of solar flux F10.7 which cover only cycles (19-23) was taken in consideration and gives predicted maximum amplitude R24 10.7 = 146, which are over estimation. Our result indicating a somewhat weaker cycle 24 as compared to cycles 21-23.

  11. Eugenol--the active principle from cloves inhibits 5-lipoxygenase activity and leukotriene-C4 in human PMNL cells.

    PubMed

    Raghavenra, H; Diwakr, B T; Lokesh, B R; Naidu, K A

    2006-01-01

    Polymorphonuclear leukocytes (PMNL) play an important role in the modulation of inflammatory conditions in humans. PMNL cells recruited at the site of inflammation, release inflammatory mediators such as leukotrienes, proteolytic enzymes and reactive oxygen species. Among these, leukotrienes are implicated in pathophysiology of allergic and inflammatory disorders like asthma, allergic rhinitis, arthritis, inflammatory bowel disease and psoriasis. 5-lipoxygenase (5-LO) is the key enzyme in biosynthetic pathway of leukotrienes. Our earlier studies showed that spice phenolic active principles significantly inhibit 5-LO enzyme in human PMNLs. In this study we have further characterized the inhibitory mechanism of eugenol, the active principle of spice-clove on 5-LO enzyme and also its effect on leukotriene C((4)) (LTC(4)). Substrate dependent enzyme kinetics showed that the inhibitory effect of eugenol on 5-LO was of a non-competitive nature. Further, eugenol was found to significantly inhibit the formation of LTC(4) in calcium ionophore A23187 and arachidonic acid (AA) stimulated PMNL cells. These data clearly suggest that eugenol inhibits 5-LO by non-competitive mechanism and also inhibits formation of LTC(4) in human PMNL cells and thus may have beneficial role in modulating 5-LO pathway in human PMNL cells. PMID:16216483

  12. Present-day aeolian activity in Herschel Crater, Mars

    NASA Astrophysics Data System (ADS)

    Cardinale, Marco; Silvestro, Simone; Vaz, David A.; Michaels, Timothy; Bourke, Mary C.; Komatsu, Goro; Marinangeli, Lucia

    2016-02-01

    In this report, we show evidence for ripple and dune migration in Herschel Crater on Mars. We estimate an average dune migration of 0.8 m and a minimum ripple migration of 1.1 m in a time span of 3.7 Earth-years. These dunes and ripples are mainly shaped by prevailing winds coming from the north, however we also report the presence of secondary winds which elongate the barchans' horns. Such a complex wind scenario is likely caused by the influence of winds blowing off the western crater rim as suggested by the Mars Regional Atmospheric Modeling System (MRAMS), an atmospheric mesoscale model. A multi-directional wind regime at the local scale is also supported by the observed bimodal distribution of the ripple trends. For the first time, a survey integrating the assessment of dune and ripple migration is presented, showing how dune topography can influence the migration patterns of ripples and how underlying topography appears to control the rates of dune migration.

  13. Retrospect and prospect of active principles from Chinese herbs in the treatment of dementia

    PubMed Central

    Wang, Ying; Huang, Lu-qi; Tang, Xi-can; Zhang, Hai-yan

    2010-01-01

    With an ageing population, dementia has become one of the world's primary health challenges. However, existing remedies offer limited benefits with certain side effects, which has prompted researchers to seek complementary and alternative therapies. China has long been known for abundant usage of various herbs. Some of these herbal decoctions are effective in stimulating blood circulation, supplementing vital energy and resisting aging, the lack of which are believed to underlie dementia. These herbs are regarded as new and promising sources of potential anti-dementia drugs. With the rapid evolution of life science and technology, numerous active components have been identified that are highly potent and multi-targeted with low toxicity, and therefore meet the requirements for dementia therapy. This review updates the research progress of Chinese herbs in the treatment of dementia, focusing on their effective principles. PMID:20523337

  14. Enhanced photoelectrochemical activity for Cu and Ti doped hematite: The first principles calculations

    SciTech Connect

    Meng, X. Y.; Qin, G. W.; Li, S.; Ren, Y. P.; Pei, W. L.; Zuo, L.; Wen, X. H.

    2011-03-14

    To improve photoelectrochemical (PEC) activity of hematite, the modification of energy band by doping 3d transition metal ions Cu and Ti into {alpha}-Fe{sub 2}O{sub 3} were studied via the first-principles calculations with density function theory (DFT)+U method. The results show that the band gap of hematite is {approx}2.1 eV and n-type dopant Ti improves the electric conductivity, confirmed by recent experiments. The p-type dopant Cu enhances the utilization ratio of solar energy, shifts both valance, and conduction band edges to a higher energy level, satisfying hydrogen production in the visible light driven PEC water splitting without voltage bias.

  15. Increasing physical activity levels in primary school physical education: The SHARP Principles Model

    PubMed Central

    Powell, Emma; Woodfield, Lorayne A.; Nevill, Alan M.

    2015-01-01

    Objectives: To evaluate the effectiveness of a one-year teaching intervention to increase moderate to vigorous physical activity (MVPA) during primary school physical education (PE). Methods: A quasi-experimental, non-equivalent group design involving four classes from two primary schools in the West Midlands, UK. In March 2014 schools were selected through purposive sampling to match schools in terms of size and demographics (baseline, n = 111: post-intervention, n = 95); data were collected from children in school years 3 and 4 (aged 7 to 9 years). The intervention involved developing teacher effectiveness through the SHARP Principles Model which was grounded in the Self Determination Theory (SDT), the Social Ecological Model (SEM) and three key ingredients from the Behaviour Change Taxonomy (BCT). MVPA was assessed at baseline and four weeks post-intervention using the System for Observing Fitness and Instruction Time (SOFIT). Four individual teacher interviews were conducted with the intervention school, to explore teachers' perceptions of the intervention. Results: A two-way ANOVA (Analysis of Variance) indicated large interaction effect sizes for time spent in MVPA (F(1, 27) = 11.07, p = 0.003, ηp2 = .316) and vigorous activity (VPA) (F = (1,27) = 8.557, p = .007, ηp2 = .263). PA in the intervention school increased significantly whereas in the control school MVPA remained relatively constant and VPA decreased. The qualitative findings revealed two main emergent themes: a paradigm shift and teacher's developing pedagogy. Conclusions: The intervention was effective in increasing MVPA in PE. Recommendations based on this evaluation would be for the SHARP Principles Model to be replicated and evaluated on a wider scale across a variety of contexts. PMID:26844179

  16. Three-year-olds obey the sample size principle of induction: the influence of evidence presentation and sample size disparity on young children's generalizations.

    PubMed

    Lawson, Chris A

    2014-07-01

    Three experiments with 81 3-year-olds (M=3.62years) examined the conditions that enable young children to use the sample size principle (SSP) of induction-the inductive rule that facilitates generalizations from large rather than small samples of evidence. In Experiment 1, children exhibited the SSP when exemplars were presented sequentially but not when exemplars were presented simultaneously. Results from Experiment 3 suggest that the advantage of sequential presentation is not due to the additional time to process the available input from the two samples but instead may be linked to better memory for specific individuals in the large sample. In addition, findings from Experiments 1 and 2 suggest that adherence to the SSP is mediated by the disparity between presented samples. Overall, these results reveal that the SSP appears early in development and is guided by basic cognitive processes triggered during the acquisition of input. PMID:24439115

  17. Synthesis of Analogues of Gingerol and Shogaol, the Active Pungent Principles from the Rhizomes of Zingiber officinale and Evaluation of Their Anti-Platelet Aggregation Effects

    PubMed Central

    Shih, Hung-Cheng; Chern, Ching-Yuh; Kuo, Ping-Chung; Wu, You-Cheng; Chan, Yu-Yi; Liao, Yu-Ren; Teng, Che-Ming; Wu, Tian-Shung

    2014-01-01

    The present study was aimed at discovering novel biologically active compounds based on the skeletons of gingerol and shogaol, the pungent principles from the rhizomes of Zingiber officinale. Therefore, eight groups of analogues were synthesized and examined for their inhibitory activities of platelet aggregation induced by arachidonic acid, collagen, platelet activating factor, and thrombin. Among the tested compounds, [6]-paradol (5b) exhibited the most significant anti-platelet aggregation activity. It was the most potent candidate, which could be used in further investigation to explore new drug leads. PMID:24599082

  18. BrainModes: a principled approach to modeling and measuring large-scale neuronal activity.

    PubMed

    Breakspear, Michael J; Daffertshofer, Andreas; Ritter, Petra

    2009-09-30

    Complex systems, such as the brain, exhibit multiple levels of organization due to processes which support the separation of scales across time and/or space. That is, cooperative phenomena--or "modes" of activity--occurring at one scale give rise to coherent spatiotemporal structures at a coarser scale. In turn, structures at the coarser scale constrain--and hence influence--emerging activity at a finer scale. BrainModes is an annual scientific summit which seeks to bring together experimental, computational and theoretical neuroscientists engaged at different levels of organization, with the goal of advancing a principled approach to understanding brain function based on the concept of cooperative phenomena in complex systems. Phenomena of particular interest include synchronization, stochastic influences, and spatiotemporal processes in both healthy and pathological states such as seizures. This Special Issue reports the 2008 BrainModes Workshop, held in Amsterdam (December 2008) which focused on the application of this framework to the analysis of brain oscillations and synchronization phenomena across time scales. PMID:19607859

  19. An Analysis Technique for Active Neutron Multiplicity Measurements Based on First Principles

    SciTech Connect

    Evans, Louise G; Goddard, Braden; Charlton, William S; Peerani, Paolo

    2012-08-13

    Passive neutron multiplicity counting is commonly used to quantify the total mass of plutonium in a sample, without prior knowledge of the sample geometry. However, passive neutron counting is less applicable to uranium measurements due to the low spontaneous fission rates of uranium. Active neutron multiplicity measurements are therefore used to determine the {sup 235}U mass in a sample. Unfortunately, there are still additional challenges to overcome for uranium measurements, such as the coupling of the active source and the uranium sample. Techniques, such as the coupling method, have been developed to help reduce the dependence of calibration curves for active measurements on uranium samples; although, they still require similar geometry known standards. An advanced active neutron multiplicity measurement method is being developed by Texas A&M University, in collaboration with Los Alamos National Laboratory (LANL) in an attempt to overcome the calibration curve requirements. This method can be used to quantify the {sup 235}U mass in a sample containing uranium without using calibration curves. Furthermore, this method is based on existing detectors and nondestructive assay (NDA) systems, such as the LANL Epithermal Neutron Multiplicity Counter (ENMC). This method uses an inexpensive boron carbide liner to shield the uranium sample from thermal and epithermal neutrons while allowing fast neutrons to reach the sample. Due to the relatively low and constant fission and absorption energy dependent cross-sections at high neutron energies for uranium isotopes, fast neutrons can penetrate the sample without significant attenuation. Fast neutron interrogation therefore creates a homogeneous fission rate in the sample, allowing for first principle methods to be used to determine the {sup 235}U mass in the sample. This paper discusses the measurement method concept and development, including measurements and simulations performed to date, as well as the potential

  20. Proof of principle study of the use of a CMOS active pixel sensor for proton radiography

    SciTech Connect

    Seco, Joao; Depauw, Nicolas

    2011-02-15

    Purpose: Proof of principle study of the use of a CMOS active pixel sensor (APS) in producing proton radiographic images using the proton beam at the Massachusetts General Hospital (MGH). Methods: A CMOS APS, previously tested for use in s-ray radiation therapy applications, was used for proton beam radiographic imaging at the MGH. Two different setups were used as a proof of principle that CMOS can be used as proton imaging device: (i) a pen with two metal screws to assess spatial resolution of the CMOS and (ii) a phantom with lung tissue, bone tissue, and water to assess tissue contrast of the CMOS. The sensor was then traversed by a double scattered monoenergetic proton beam at 117 MeV, and the energy deposition inside the detector was recorded to assess its energy response. Conventional x-ray images with similar setup at voltages of 70 kVp and proton images using commercial Gafchromic EBT 2 and Kodak X-Omat V films were also taken for comparison purposes. Results: Images were successfully acquired and compared to x-ray kVp and proton EBT2/X-Omat film images. The spatial resolution of the CMOS detector image is subjectively comparable to the EBT2 and Kodak X-Omat V film images obtained at the same object-detector distance. X-rays have apparent higher spatial resolution than the CMOS. However, further studies with different commercial films using proton beam irradiation demonstrate that the distance of the detector to the object is important to the amount of proton scatter contributing to the proton image. Proton images obtained with films at different distances from the source indicate that proton scatter significantly affects the CMOS image quality. Conclusion: Proton radiographic images were successfully acquired at MGH using a CMOS active pixel sensor detector. The CMOS demonstrated spatial resolution subjectively comparable to films at the same object-detector distance. Further work will be done in order to establish the spatial and energy resolution of the

  1. P2X7 Receptor Activation Impairs Exogenous MHC Class I Oligopeptides Presentation in Antigen Presenting Cells

    PubMed Central

    Baroja-Mazo, Alberto; Barberà-Cremades, Maria; Pelegrín, Pablo

    2013-01-01

    Major histocompatibility complex class I (MHC I) on antigen presenting cells (APCs) is a potent molecule to activate CD8+ T cells and initiate immunity. P2X7 receptors (P2X7Rs) are present on the plasma membrane of APCs to sense the extracellular danger signal adenosine-5′-triphosphate (ATP). P2X7R activates the inflammasome and the release of IL-1β in macrophages and other immune cells to initiate the inflammatory response. Here we show that P2X7R stimulation by ATP in APCs decreased the amount of MHC I at the plasma membrane. Specific antagonism or genetic ablation of P2X7R inhibited the effects of ATP on levels of cellular MHC I. Furthermore, P2X7R stimulation was able to inhibit activation of CD8+ T cells via specific MHC I-oligopeptide complexes. Our study suggests that P2X7R activation on APCs is a novel inhibitor of adaptive CD8+ T cell immunity. PMID:23940597

  2. P2X7 receptor activation impairs exogenous MHC class I oligopeptides presentation in antigen presenting cells.

    PubMed

    Baroja-Mazo, Alberto; Barberà-Cremades, Maria; Pelegrín, Pablo

    2013-01-01

    Major histocompatibility complex class I (MHC I) on antigen presenting cells (APCs) is a potent molecule to activate CD8(+) T cells and initiate immunity. P2X7 receptors (P2X7Rs) are present on the plasma membrane of APCs to sense the extracellular danger signal adenosine-5'-triphosphate (ATP). P2X7R activates the inflammasome and the release of IL-1β in macrophages and other immune cells to initiate the inflammatory response. Here we show that P2X7R stimulation by ATP in APCs decreased the amount of MHC I at the plasma membrane. Specific antagonism or genetic ablation of P2X7R inhibited the effects of ATP on levels of cellular MHC I. Furthermore, P2X7R stimulation was able to inhibit activation of CD8(+) T cells via specific MHC I-oligopeptide complexes. Our study suggests that P2X7R activation on APCs is a novel inhibitor of adaptive CD8(+) T cell immunity. PMID:23940597

  3. Improved GC method for the determination of the active principles of Catha edulis.

    PubMed

    Dell'acqua, Lucia; Roda, Gabriella; Arnoldi, Sebastiano; Rusconi, Chiara; Turati, Lorenzo; Gambaro, Veniero

    2013-06-15

    The GC method previously reported by our research group for the analysis of the active principles of Catha edulis, i.e. cathine, cathinone and phenylpropanolamine, was considerably improved. N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA) as derivatizing agent was employed, thus allowing an accurate determination of the analytes and a suitable internal standard for quantitative analyses (nicotinamide) was introduced. Moreover the chromatographic conditions were carefully studied to improve the separation of the alkaloids and sensitivity. To this end different chromatographic capillary columns and temperature gradients were investigated. The optimized GC method was validated and resulted adequate for the application in forensic analysis. Finally on behalf of the Tribunal, C. edulis vegetable material seized by the police in northern Italy was analyzed, the quantity of cathine ranging from 0.095 to 0.29%, the quantity of PPA from 0.010 to 0.21% and the quantity of cathinone from 0.025 to 0.374% of the weight of the vegetable material. PMID:23685239

  4. Active Pharmaceutical Ingredients: Prediction of Physical-Chemical Properties from First Principles

    NASA Astrophysics Data System (ADS)

    Valenzano, Loredana

    2013-03-01

    Polymorphism in active pharmaceutical ingredients (APIs) plays a crucial role both for medical and intellectual property concerns but despite ongoing efforts, experimental and computational investigations of the existence and the physical-chemical properties of the same compound in different forms is still an open question.While comparison between computed and experimental values for properties derived from differences between states is often promising (such as bulk modulus), results are disappointing for absolute values (such as density). Quantum mechanical computational methods describe the systems at 0K, experimentally properties are often evaluated at room temperature. Therefore it is not surprising that results determined from first principles dramatically differ from those obtained experimentally. By applying a quantum mechanical periodic approach that takes into account long range London dispersion forces fitted for solid materials, and by imposing different cell volumes corresponding to different thermodynamic conditions, we show how results from calculations at 0K (structures, vibrational spectra, elastic constants) may be compared to experimental values at higher temperatures, helping to foster a stronger linkage between computational and experimental work on systems such as APIs. Where experimental results are not available, our work represents an innovative approach in addressing the properties of APIs. Our results can also serve as foundation for the developing of new force fields to be adopted within a multi-scale computational approach.

  5. Data-Based Active Learning in the Principles of Macroeconomics Course: A Mock FOMC Meeting

    ERIC Educational Resources Information Center

    Whiting, Cathleen

    2006-01-01

    The author presents an active-learning exercise for the introductory macroeconomics class in which students participate in a mock Federal Open Market Committee (FOMC) meeting. Preparation involves data gathering and writing both a research report and a policy recommendation. An FOMC meeting is simulated in which students give their policy…

  6. Electrostatic Positioning System for a free fall test at drop tower Bremen and an overview of tests for the Weak Equivalence Principle in past, present and future

    NASA Astrophysics Data System (ADS)

    Sondag, Andrea; Dittus, Hansjörg

    2016-08-01

    The Weak Equivalence Principle (WEP) is at the basis of General Relativity - the best theory for gravitation today. It has been and still is tested with different methods and accuracies. In this paper an overview of tests of the Weak Equivalence Principle done in the past, developed in the present and planned for the future is given. The best result up to now is derived from the data of torsion balance experiments by Schlamminger et al. (2008). An intuitive test of the WEP consists of the comparison of the accelerations of two free falling test masses of different composition. This has been carried through by Kuroda & Mio (1989, 1990) with the up to date most precise result for this setup. There is still more potential in this method, especially with a longer free fall time and sensors with a higher resolution. Providing a free fall time of 4.74 s (9.3 s using the catapult) the drop tower of the Center of Applied Space Technology and Microgravity (ZARM) at the University of Bremen is a perfect facility for further improvements. In 2001 a free fall experiment with high sensitive SQUID (Superconductive QUantum Interference Device) sensors tested the WEP with an accuracy of 10-7 (Nietzsche, 2001). For optimal conditions one could reach an accuracy of 10-13 with this setup (Vodel et al., 2001). A description of this experiment and its results is given in the next part of this paper. For the free fall of macroscopic test masses it is important to start with precisely defined starting conditions concerning the positions and velocities of the test masses. An Electrostatic Positioning System (EPS) has been developed to this purpose. It is described in the last part of this paper.

  7. LC-MS Guided Isolation of Bioactive Principles from Iris hookeriana and Bioevaluation of Isolates for Antimicrobial and Antioxidant Activities.

    PubMed

    Dar, B A; Lone, S H; Shah, W A; Bhat, K A

    2016-08-01

    The genus Iris is diverse both in the abundance of secondary metabolities as well as the biological activities. The rhizomes of Iris hookeriana exhibit significant anthelminthic activity against gastrointestinal nematodes of sheep. Although Iris hookeriana has been a subject of the study of so many phytochemical studies, yet we report some constituents for the first time from this plant using a different isolation approach. This manuscript presents the isolation, antimicrobial and antioxidant evaluation of bioactive principles from Iris hookeriana. LC-MS guided isolation technique was applied for the separation of target constituents. The isolates were characterised by spectral techniques and subjected to antioxidant evaluation by DPPH assay. Four compounds; resveratrol, resveratroloside, junipeginin C and isorhamnetin-3-O-neohesperidoside were isolated for the first time along with 3 known compounds viz piceid, irigenin and iridin from I. hookeriana using this approach. The antioxidant activity screening of the isolates revealed that all the 4 constituents isolated for the first time, have strong antioxidant potential with IC50 of 14.0 µg/ml (resveratroloside), 19.7 µg/ml (junipeginen C), 12.8 µg/ml (resveratrol) and 19.8 µg/ml (isorhamnetin-3-O-neohesperodoside). So it can be safely concluded that LC-MS guided isolation of chemical compounds from Iris hookeriana has furnished 4 antioxidant constituents. Thus Iris hookeriana can act as as a good source of wonder molecule resveratrol and its 2 glycosides, resveratrolside and piceid which upon hydrolysis can be converted into the parent drug resveratrol. PMID:27281447

  8. First-principles study of carbon impurities in CuInSe2 and CuGaSe2, present in non-vacuum synthesis methods

    NASA Astrophysics Data System (ADS)

    Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D.

    2015-01-01

    A first-principles study of the structural and electronic properties of carbon impurities in CuInSe2 and CuGaSe2 is presented. Carbon is present in organic molecules in the precursor solutions used in non-vacuum growth methods for CuInSe2 and CuGaSe2 based photovoltaic cells. These growth methods make more efficient use of material, time, and energy than traditional vacuum methods. The formation energies of several carbon impurities are calculated using the hybrid HSE06 functional. CCu acts as a shallow donor, CIn and interstitial C yield deep donor levels in CuInSe2, while in CuGaSe2 CGa and interstitial C act as deep amphoteric defects. So, these defects reduce the majority carrier (hole) concentration in p-type CuInSe2 and CuGaSe2 by compensating the acceptor levels. The deep defects are likely to act as recombination centers for the photogenerated charge carriers and are thus detrimental for the performance of the photovoltaic cells. On the other hand, the formation energies of the carbon impurities are high, even under C-rich growth conditions. Thus, few C impurities will form in CuInSe2 and CuGaSe2 in thermodynamic equilibrium. However, the deposition of the precursor solution in non-vacuum growth methods presents conditions far from thermodynamic equilibrium. In this case, our calculations show that C impurities formed in non-equilibrium tend to segregate from CuInSe2 and CuGaSe2 by approaching thermodynamic equilibrium, e.g., via thorough annealing.

  9. First-principles study of carbon impurities in CuInSe{sub 2} and CuGaSe{sub 2}, present in non-vacuum synthesis methods

    SciTech Connect

    Bekaert, J. Saniz, R.; Partoens, B.; Lamoen, D.

    2015-01-07

    A first-principles study of the structural and electronic properties of carbon impurities in CuInSe{sub 2} and CuGaSe{sub 2} is presented. Carbon is present in organic molecules in the precursor solutions used in non-vacuum growth methods for CuInSe{sub 2} and CuGaSe{sub 2} based photovoltaic cells. These growth methods make more efficient use of material, time, and energy than traditional vacuum methods. The formation energies of several carbon impurities are calculated using the hybrid HSE06 functional. C{sub Cu} acts as a shallow donor, C{sub In} and interstitial C yield deep donor levels in CuInSe{sub 2}, while in CuGaSe{sub 2} C{sub Ga} and interstitial C act as deep amphoteric defects. So, these defects reduce the majority carrier (hole) concentration in p-type CuInSe{sub 2} and CuGaSe{sub 2} by compensating the acceptor levels. The deep defects are likely to act as recombination centers for the photogenerated charge carriers and are thus detrimental for the performance of the photovoltaic cells. On the other hand, the formation energies of the carbon impurities are high, even under C-rich growth conditions. Thus, few C impurities will form in CuInSe{sub 2} and CuGaSe{sub 2} in thermodynamic equilibrium. However, the deposition of the precursor solution in non-vacuum growth methods presents conditions far from thermodynamic equilibrium. In this case, our calculations show that C impurities formed in non-equilibrium tend to segregate from CuInSe{sub 2} and CuGaSe{sub 2} by approaching thermodynamic equilibrium, e.g., via thorough annealing.

  10. How to Present Evidence-Based Usability Design Principles Dedicated to Medication-Related Alerting Systems to Designers and Evaluators? Results from a Workshop.

    PubMed

    Marcilly, Romaric; Monkman, Helen; Villumsen, Sidsel; Kaufman, David; Beuscart-Zephir, Marie-Catherine

    2016-01-01

    Medication alerting system use errors and lack of adoption are often attributed to usability issues. Previous work has used evidence from the literature to reveal usability principles specific to medication alerting systems and identify potential consequences of violating these principles. The current study sought to explore how best to convey these principles to designers and evaluators of these systems to facilitate their work. To this aim, a workshop with 19 participants was used to generate ideas and opinions on how to deliver these topic-specific design principles in a way that would be most helpful for them. Participants generated ideas for how (e.g., a collaborative, continuously updated forum) and what (e.g., illustrations, checklists, evidence sources and strength, consequences of violations) information is most useful to disseminate usability principles for medication alerting systems. Participants, especially designers, expressed desire to use these principles in practice and avoid previously documented mistakes and therefore make design and evaluation of these systems more effective and efficient. Those insights are discussed in terms of feasibility and logistical challenges to developing the proposed documentation). To move this work forward, a more collaborative approach of Human Factors specialists in medical informatics is necessary. PMID:27577456

  11. SETI-Italia: Present Activities and Future Real Time Data Processing System

    NASA Astrophysics Data System (ADS)

    Montebugnoli, S.; Bianchi, G.; Bartolini, M.; Mattana, A.; Monari, J.; Naldi, G.; Perini, F.; Pluchino, S.; Pupillo, G.

    2010-04-01

    A complete review of present SETI-Italia activities and data processing systems are presented. The future plan is to develop a new very powerful data processing reconfigurable platform (based on FPGAs) to implement even more powerful real time algorithms.

  12. Protection of ornamental gold fish Carassius auratus against Aeromonas hydrophila by treating Ixora coccinea active principles.

    PubMed

    Anusha, Paulraj; Thangaviji, Vijayaragavan; Velmurugan, Subramanian; Michaelbabu, Mariavincent; Citarasu, Thavasimuthu

    2014-02-01

    Herbals such as Ixora coccinea, Daemia extensa and Tridax procumbens were selected to screen in vitro antibacterial and immunostimulant activity against the freshwater fish pathogen Aeromonas hydrophila using different organic polar and non-polar solvents. Initial screening results revealed that, ethyl acetate extracts and its purified fraction of I. coccinea was able to suppress the A. hydrophila strains at more than 15 mm of zone of inhibition and positive immunostimulant activity. The purified active fraction, which eluted from H40: EA60 mobile phase was structurally characterized by GC-MS analysis. Two compounds such as Diethyl Phthalate (1,2-Benzene dicarboxylic acid, monobutyl ester) and Dibutyl Phthalate were characterized using NIST database search. In order to study the in vivo immunostimulant influence of the compounds, the crude extracts (ICE) and purified fractions (ICF) were incorporated to the artificial diets at the concentration of 400 mg kg⁻¹ and fed to the ornamental gold fish Carassius auratus for 30 days. After termination of feeding experiment, they were challenged with highly virulent A. hydrophila AHV-1 which was isolated from infected gold fish and studied the survival, specific bacterial load reduction, serum biochemistry, haematology, immunology and histological parameters. The control diet fed fishes succumbed to death within five days at 100% mortality whereas ICE and ICF fed groups survived 60 and 80% respectively after 10 days. The diets also helped to decrease the Aeromonas load after challenge and significantly (P ≤ 0.01) improved the serum albumin, globulin and protein. The diets also helped to increase the RBC and haemoglobin level significantly (P ≤ 0.05) from the control group. Surprisingly the immunological parameters like phagocytic activity, serum bactericidal activity and lysozyme activity were significantly increased (P ≤ 0.001) in the experimental diets. Macrophages and erythrocytes were abundantly expressed in the

  13. Physical Activity and Pregnancy: Past and Present Evidence and Future Recommendations

    ERIC Educational Resources Information Center

    Symons Downs, Danielle; Chasan-Taber, Lisa; Evenson, Kelly R.; Leiferman, Jenn; Yeo, SeonAe

    2012-01-01

    Purpose: In this review, we provide researchers and practitioners with an overview of the physical activity and pregnancy literature to promote prenatal physical activity, improve measurement, further elucidate the role of activity in reducing maternal health complications, and inform future research. Method: We examined past and present physical…

  14. Investigation into the antioxidant and antidiabetic potential of Moringa stenopetala: identification of the active principles.

    PubMed

    Habtemariam, Solomon

    2015-03-01

    The fresh leaves of Moringa stenopetala (family, Moringaceae) are commonly eaten as cabbage while dried leaves are used as nutritional supplement and for treating a variety of disease conditions including diabetes. The present investigation into the therapeutic potential of the leaves and seeds of the plant revealed no inhibitory effect against α-glucosidase enzyme up to the concentration of 200 μg/mL but the leaves extract displayed potent DPPH (1,1-diphenyl-2- picrylhydrazyl) radical scavenging effect (IC50, 59.5 ± 4.1 μg/mL). An activity directed fractionation and isolation procedure resulted in the identification of the major antioxidant compound as rutin and minor active component, neochlorogenic acid. Both the crude extract (0.8-200 μg/mL) and rutin (0.8-200 μM) but not neochlorogenic acid displayed a concentration-dependent protection of human pancreatic β-cells (1.4E7 cells) from oxidant-induced cell death. The identification of these compounds along with their potential role in the nutritional and medicinal significance of the plant is discussed. PMID:25924532

  15. Principles of project management

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The basic principles of project management as practiced by NASA management personnel are presented. These principles are given as ground rules and guidelines to be used in the performance of research, development, construction or operational assignments.

  16. The effect of fast and slow motor unit activation on whole-muscle mechanical performance: the size principle may not pose a mechanical paradox

    PubMed Central

    Holt, N. C.; Wakeling, J. M.; Biewener, A. A.

    2014-01-01

    The output of skeletal muscle can be varied by selectively recruiting different motor units. However, our knowledge of muscle function is largely derived from muscle in which all motor units are activated. This discrepancy may limit our understanding of in vivo muscle function. Hence, this study aimed to characterize the mechanical properties of muscle with different motor unit activation. We determined the isometric properties and isotonic force–velocity relationship of rat plantaris muscles in situ with all of the muscle active, 30% of the muscle containing predominately slower motor units active or 20% of the muscle containing predominately faster motor units active. There was a significant effect of active motor unit type on isometric force rise time (p < 0.001) and the force–velocity relationship (p < 0.001). Surprisingly, force rise time was longer and maximum shortening velocity higher when all motor units were active than when either fast or slow motor units were selectively activated. We propose this is due to the greater relative effects of factors such as series compliance and muscle resistance to shortening during sub-maximal contractions. The findings presented here suggest that recruitment according to the size principle, where slow motor units are activated first and faster ones recruited as demand increases, may not pose a mechanical paradox, as has been previously suggested. PMID:24695429

  17. Four Practical Principles for Enhancing Vocabulary Instruction

    ERIC Educational Resources Information Center

    Manyak, Patrick C.; Von Gunten, Heather; Autenrieth, David; Gillis, Carolyn; Mastre-O'Farrell, Julie; Irvine-McDermott, Elizabeth; Baumann, James F.; Blachowicz, Camille L. Z.

    2014-01-01

    This article presents four practical principles that lead to enhanced word-meaning instruction in the elementary grades. The authors, a collaborative team of researchers and classroom teachers, identified and developed these principles and related instructional activities during a three-year vocabulary instruction research project. The principles…

  18. Summaries of "You Do It" Activities Presented at the 1978 SASTA Conference in the Riverland.

    ERIC Educational Resources Information Center

    Walsh, Terry

    1980-01-01

    Summarizes "you do it" activities presented at the 1978 South Australian Science Teachers Association Conference. Topics include microscope use and maintenance, chemical slide cells, chemical models, sound waves, microwaves, astronomy, plant keys, reading geological maps, and natural dye processes. (DS)

  19. β-Asarone, an active principle of Acorus calamus rhizome, inhibits morphogenesis, biofilm formation and ergosterol biosynthesis in Candida albicans.

    PubMed

    Rajput, Sandeep B; Karuppayil, S Mohan

    2013-01-15

    Anti-Candida potential of Acorus calamus rhizome and its active principle, β-asarone, was evaluated against the human fungal pathogen, Candida albicans. β-Asarone exhibited promising growth inhibitory activity at 0.5mg/ml and it was fungicidal at 8 mg/ml. Time dependant kill curve assay showed that MFC of β-asarone was highly toxic to C. albicans, killing 99.9% inoculum within 120 min of exposure. β-Asarone caused significant inhibition of C. albicans morphogenesis and biofilm development at sub-inhibitory concentrations. Our data indicate that the growth inhibitory activity of β-asarone might be through inhibition of ergosterol biosynthesis. Hemolytic assay showed that β-asarone is non-toxic, even at concentrations approaching MIC value. Our results suggest that β-asarone may be safe as a topical antifungal agent. PMID:23123225

  20. Physical Activity and Pregnancy: Past and Present Evidence and Future Recommendations

    PubMed Central

    Downs, Danielle Symons; Chasan-Taber, Lisa; Evenson, Kelly R.; Leiferman, Jenn; Yeo, SeonAe

    2012-01-01

    Purpose This review provides researchers and practitioners with an overview of the physical activity and pregnancy literature to promote prenatal physical activity, improve measurement, further elucidate the role of activity in reducing maternal health complications, and inform future research. Methods We examined past and present physical activity and pregnancy studies and highlight key papers with a particular focus on maternal health outcomes to best inform physical activity promotion efforts. Results This review discusses: (a) historical overview of prenatal physical activity with a specific focus on the physical activity guidelines, how they have changed over time, and how evidence of the effect of prenatal activity on maternal/fetal health outcomes has impacted clinical recommendations; (b) existing tools and challenges associated with measuring prenatal physical activity; (c) empirical evidence on the multi-level determinants of prenatal activity to help guide future intervention work; (d) empirical evidence of prenatal activity on adverse maternal outcomes (gestational diabetes mellitus, preeclampsia, excessive gestational weight gain) from observational and intervention studies; and (e) summary/recommendations for future research and practice. Conclusions The physical activity and pregnancy literature has evolved over the past 50 years and there is currently sufficient empirical evidence to support the promotion of moderate to vigorous prenatal physical activity for maternal health benefits. Future studies and interventions should be carefully-designed, theoretically driven, and include validated and reliable measures of activity. Researchers and practitioners should also consider the multifaceted determinants and outcomes of prenatal physical activity and intervening to promote physical activity before, during, and after pregnancy. PMID:23367811

  1. Re-Mediating Classroom Activity with a Non-Linear, Multi-Display Presentation Tool

    ERIC Educational Resources Information Center

    Bligh, Brett; Coyle, Do

    2013-01-01

    This paper uses an Activity Theory framework to evaluate the use of a novel, multi-screen, non-linear presentation tool. The Thunder tool allows presenters to manipulate and annotate multiple digital slides and to concurrently display a selection of juxtaposed resources across a wall-sized projection area. Conventional, single screen presentation…

  2. "JCE" Classroom Activity #108. Using Archimedes' Principle to Explain Floating and Sinking Cans

    ERIC Educational Resources Information Center

    Sanger, Michael J.

    2011-01-01

    In this activity, students (working alone or in groups) measure the mass of several soda cans (diet and regular soda) along with the mass of water that each can displaces. The students are then asked to compare these two mass values for the sinking cans and for the floating cans. The purpose of this activity is for students to determine that the…

  3. First-principles prediction of kink-pair activation enthalpy on screw dislocations in bcc transition metals: V, Nb, Ta, Mo, W, and Fe

    NASA Astrophysics Data System (ADS)

    Dezerald, L.; Proville, L.; Ventelon, Lisa; Willaime, F.; Rodney, D.

    2015-03-01

    The atomistic study of kink pairs on screw dislocations in body-centered cubic (bcc) metals is challenging because interatomic potentials in bcc metals still lack accuracy and kink pairs require too many atoms to be modeled by first principles. Here, we circumvent this difficulty using a one-dimensional line tension model whose parameters, namely the line tension and Peierls barrier, are reachable to density functional theory calculations. The model parameterized in V, Nb, Ta, Mo, W, and Fe, is used to study the kink-pair activation enthalpy and spatial extension. Interestingly, we find that the atomistic line tension is more than twice the usual elastic estimates. The calculations also show interesting group tendencies with the line tension and kink-pair width larger in group V than in group VI elements. Finally, the present kink-pair activation energies are shown to compare qualitatively with experimental data and potential origins of quantitative discrepancies are discussed.

  4. Determination of the active principles of Catha Edulis: quali-quantitative analysis of cathinone, cathine, and phenylpropanolamine.

    PubMed

    Gambaro, Veniero; Arnoldi, Sebastiano; Colombo, Maria Laura; Dell'Acqua, Lucia; Guerrini, Katia; Roda, Gabriella

    2012-04-10

    In the last years, all the vegetable material supposed to belong to the Catha Edulis species, seized at the Malpensa and Orio al Serio airports, were analyzed in our laboratory on behalf of the Tribunals of Busto Arsizio and Bergamo, respectively. After a preliminary botanic examination, the quali-quantitative determination of the active principles cathinone, cathine and phenylpropanolamine (PPA) was carried out by means of GC/MS and GC/FID techniques, which meet the requirements of the forensic analyses. We developed a fast, effective and reliable derivatization procedure which allowed to simultaneously detect cathine and PPA, whose discrimination is mandatory since PPA is not a psychoactive agent. Cathine was distributed in the various parts of the plant (leaves and stems) and its quantity ranged from 0.03% to 0.17% of the weight of the vegetable material; PPA was not detected in the twigs and its quantity in the leaves ranged from 0.07% to 0.16%. The quantitative determination of cathinone was carried out directly on the methanol solution after maceration of the vegetable material, its quantity ranging from 0.02% to 0.10%. No significant difference in the content of the two active principles was found between the fresh and the dried material. PMID:22024653

  5. Bernoulli's Principle

    ERIC Educational Resources Information Center

    Hewitt, Paul G.

    2004-01-01

    Some teachers have difficulty understanding Bernoulli's principle particularly when the principle is applied to the aerodynamic lift. Some teachers favor using Newton's laws instead of Bernoulli's principle to explain the physics behind lift. Some also consider Bernoulli's principle too difficult to explain to students and avoid teaching it…

  6. Principles of root bark of Hippocratea excelsa (Hippocrataceae) with gastroprotective activity.

    PubMed

    Navarrete, Andrés; Trejo-Miranda, José Luis; Reyes-Trejo, Lino

    2002-03-01

    The aqueous and ethanol extracts of the root bark of Hippocratea excelsa HBK. Locally known as 'Cancerina', showed an important gastroprotective effect in several experimental ulcer models in rats. Fractionation of the methanol extract led to four pools of active fractions (F1-F4). Sitosterol-3-O-beta-glucoside, beta-sitosterol and (-) epicatechin were isolated from the active fractions and showed an important gastroprotective activity (93.4,85.7 and 72.1% of gastroprotection, respectively), whereas bismuth subsalicylate, used as positive control, showed 46.2% of gastroprotection. A mixture of alpha-amyrin and beta-amyrin showed 50% of gastroprotection. Friedelin, canophyllal and canophyllol were isolated from the active fractions, but they were inactive as gastroprotective compounds. These results provide additional support for the popular use of this plant as an antiulcer remedy in the Mexican traditional medicine. PMID:11849847

  7. Development of coherent neuronal activity patterns in mammalian cortical networks: common principles and local hetereogeneity.

    PubMed

    Egorov, Alexei V; Draguhn, Andreas

    2013-01-01

    Many mammals are born in a very immature state and develop their rich repertoire of behavioral and cognitive functions postnatally. This development goes in parallel with changes in the anatomical and functional organization of cortical structures which are involved in most complex activities. The emerging spatiotemporal activity patterns in multi-neuronal cortical networks may indeed form a direct neuronal correlate of systemic functions like perception, sensorimotor integration, decision making or memory formation. During recent years, several studies--mostly in rodents--have shed light on the ontogenesis of such highly organized patterns of network activity. While each local network has its own peculiar properties, some general rules can be derived. We therefore review and compare data from the developing hippocampus, neocortex and--as an intermediate region--entorhinal cortex. All cortices seem to follow a characteristic sequence starting with uncorrelated activity in uncoupled single neurons where transient activity seems to have mostly trophic effects. In rodents, before and shortly after birth, cortical networks develop weakly coordinated multineuronal discharges which have been termed synchronous plateau assemblies (SPAs). While these patterns rely mostly on electrical coupling by gap junctions, the subsequent increase in number and maturation of chemical synapses leads to the generation of large-scale coherent discharges. These patterns have been termed giant depolarizing potentials (GDPs) for predominantly GABA-induced events or early network oscillations (ENOs) for mostly glutamatergic bursts, respectively. During the third to fourth postnatal week, cortical areas reach their final activity patterns with distinct network oscillations and highly specific neuronal discharge sequences which support adult behavior. While some of the mechanisms underlying maturation of network activity have been elucidated much work remains to be done in order to fully

  8. Quantitative (13)C Solid-State NMR Spectra by Multiple-Contact Cross-polarization for Drug Delivery: From Active Principles to Excipients and Drug Carriers.

    PubMed

    Saïdi, Fadila; Taulelle, Francis; Martineau, Charlotte

    2016-08-01

    In this contribution, we present an analysis of the main parameters influencing the efficiency of the (1)H → (13)C multiple-contact cross-polarization nuclear magnetic resonance (NMR) experiment in the context of solid pharmaceutical materials. Using the optimum experimental conditions, quantitative (13)C NMR spectra are then obtained for porous metal-organic frameworks (potential drug carriers) and for components present in drug formulations (active principle ingredient and excipients, amorphous or crystalline). Finally, we show that mixtures of components can also be quantified with this method and, hence, that it represents an ideal tool for quantification of pharmaceutical formulations by (13)C cross-polarization under magic-angle spinning NMR in the industry as it is robust and easy to set up, much faster than direct (13)C polarization and is efficient for samples at natural abundance. PMID:27372550

  9. Searching for active binary rutile oxide catalyst for water splitting from first principles.

    PubMed

    Chen, Dong; Fang, Ya-Hui; Liu, Zhi-Pan

    2012-12-28

    Water electrolysis is an important route to large-scale hydrogen production using renewable energy, in which the oxygen evolution reaction (OER: 2H(2)O → O(2) + 4H(+) + 4e(-)) causes the largest energy loss in traditional electrocatalysts involving Ru-Ir mixed oxides. Following our previous mechanistic studies on the OER on RuO(2)(110) (J. Am. Chem. Soc. 2010, 132, 18214), this work aims to provide further insight into the key parameters relevant to the activity of OER catalysts by investigating a group of rutile-type binary metal oxides, including RuNiO(2), RuCoO(2), RuRhO(2), RuIrO(2) and OsIrO(2). Two key aspects are focused on, namely the surface O coverage at the relevant potential conditions and the kinetics of H(2)O activation on the O-covered surfaces. The O coverage for all the oxides investigated here is found to be 1 ML at the concerned potential (1.23 V) with all the exposed metal cations being covered by terminal O atoms. The calculated free energy barrier for the H(2)O dissociation on the O covered surfaces varies significantly on different surfaces. The highest OER activity occurs at RuCoO(2) and RuNiO(2) oxides with a predicted activity about 500 times higher than pure RuO(2). On these oxides, the surface bridging O near the terminal O atom has a high activity for accepting the H during H(2)O splitting. It is concluded that while the differential adsorption energy of the terminal O atom influences the OER activity to the largest extent, the OER activity can still be tuned by modifying the electronic structure of surface bridging O. PMID:22941355

  10. Cellular Telephones Measure Activity and Lifespace in Community-Dwelling Adults: Proof of Principle

    PubMed Central

    Schenk, Ana Katrin; Witbrodt, Bradley C.; Hoarty, Carrie A.; Carlson, Richard H.; Goulding, Evan H.; Potter, Jane F.; Bonasera, Stephen J.

    2011-01-01

    OBJECTIVES To describe a system that uses off-the-shelf sensor and telecommunication technologies to continuously measure individual lifespace and activity levels in a novel way. DESIGN Proof of concept involving three field trials of 30, 30, and 21 days. SETTING Omaha, Nebraska, metropolitan and surrounding rural region. PARTICIPANTS Three participants (48-year-old man, 33-year-old woman, and 27-year-old male), none with any functional limitations. MEASUREMENTS Cellular telephones were used to detect in-home position and in-community location and to measure physical activity. Within the home, cellular telephones and Bluetooth transmitters (beacons) were used to locate participants at room-level resolution. Outside the home, the same cellular telephones and global positioning system (GPS) technology were used to locate participants at a community-level resolution. Physical activity was simultaneously measured using the cellular telephone accelerometer. RESULTS This approach had face validity to measure activity and lifespace. More importantly, this system could measure the spatial and temporal organization of these metrics. For example, an individual’s lifespace was automatically calculated across multiple time intervals. Behavioral time budgets showing how people allocate time to specific regions within the home were also automatically generated. CONCLUSION Mobile monitoring shows much promise as an easily deployed system to quantify activity and lifespace, important indicators of function, in community-dwelling adults. PMID:21288235

  11. Transforming Principles into Practice: Using Cognitive Active Learning Strategies in the High School Classroom

    ERIC Educational Resources Information Center

    Swiderski, Suzanne M.

    2011-01-01

    High school teachers who engage students through active learning in their classrooms can more fully understand this instructional practice by examining the theories and strategies underlying the cognitive perspective of educational psychology, which addresses the development of knowledge in the individual mind. Two theoretical explanations,…

  12. Antigen Presentation and T-Cell Activation Are Critical for RBP4-Induced Insulin Resistance.

    PubMed

    Moraes-Vieira, Pedro M; Castoldi, Angela; Aryal, Pratik; Wellenstein, Kerry; Peroni, Odile D; Kahn, Barbara B

    2016-05-01

    Adipose tissue (AT) inflammation contributes to impaired insulin action, which is a major cause of type 2 diabetes. RBP4 is an adipocyte- and liver-derived protein with an important role in insulin resistance, metabolic syndrome, and AT inflammation. RBP4 elevation causes AT inflammation by activating innate immunity, which elicits an adaptive immune response. RBP4-overexpressing mice (RBP4-Ox) are insulin resistant and glucose intolerant and have increased AT macrophages and T-helper 1 cells. We show that high-fat diet-fed RBP4(-/-) mice have reduced AT inflammation and improved insulin sensitivity versus wild type. We also elucidate the mechanism for RBP4-induced macrophage antigen presentation and subsequent T-cell activation. In RBP4-Ox, AT macrophages display enhanced c-Jun N-terminal kinase, extracellular signal-related kinase, and p38 phosphorylation. Inhibition of these pathways and of NF-κB reduces activation of macrophages and CD4 T cells. MyD88 is an adaptor protein involved in proinflammatory signaling. In macrophages from MyD88(-/-) mice, RBP4 fails to stimulate secretion of tumor necrosis factor, IL-12, and IL-6 and CD4 T-cell activation. In vivo blockade of antigen presentation by treating RBP4-Ox mice with CTLA4-Ig, which blocks costimulation of T cells, is sufficient to reduce AT inflammation and improve insulin resistance. Thus, MyD88 and downstream mitogen-activated protein kinase and NF-κB pathways are necessary for RBP4-induced macrophage antigen presentation and subsequent T-cell activation. Also, blocking antigen presentation with CTLA4-Ig improves RBP4-induced insulin resistance and macrophage-induced T-cell activation. PMID:26936962

  13. Understanding Iron-based catalysts with efficient Oxygen reduction activity from first-principles calculations

    NASA Astrophysics Data System (ADS)

    Hafiz, Hasnain; Barbiellini, B.; Jia, Q.; Tylus, U.; Strickland, K.; Bansil, A.; Mukerjee, S.

    2015-03-01

    Catalysts based on Fe/N/C clusters can support the oxygen-reduction reaction (ORR) without the use of expensive metals such as platinum. These systems can also prevent some poisonous species to block the active sites from the reactant. We have performed spin-polarized calculations on various Fe/N/C fragments using the Vienna Ab initio Simulation Package (VASP) code. Some results are compared to similar calculations obtained with the Gaussian code. We investigate the partial density of states (PDOS) of the 3d orbitals near the Fermi level and calculate the binding energies of several ligands. Correlations of the binding energies with the 3d electronic PDOS's are used to propose electronic descriptors of the ORR associated with the 3d states of Fe. We also suggest a structural model for the most active site with a ferrous ion (Fe2+) in the high spin state or the so-called Doublet 3 (D3).

  14. Stimulation of hormone-responsive adenylate cyclase activity by a factor present in the cell cytosol.

    PubMed Central

    MacNeil, S; Crawford, A; Amirrasooli, H; Johnson, S; Pollock, A; Ollis, C; Tomlinson, S

    1980-01-01

    1. Homogenates of whole tissues were shown to contain both intracellular and extracellular factors that affected particulate adenylate cyclase activity in vitro. Factors present in the extracellular fluids produced an inhibition of basal, hormone- and fluoride-stimulated enzyme activity but factors present in the cell cytosol increased hormone-stimulated activity with relatively little effect on basal or fluoride-stimulated enzyme activity. 2. The existence of this cytosol factor or factors was investigated using freshly isolated human platelets, freshly isolated rat hepatocytes, and cultured cells derived from rat osteogenic sarcoma, rat calvaria, mouse melanoma, pig aortic endothelium, human articular cartilage chondrocytes and human bronchial carcinoma (BEN) cells. 3. The stimulation of the hormone response by the cytosol factor ranged from 60 to 890% depending on the tissue of origin of the adenylate cyclase. 4. In each case the behaviour of the factor was similar to the action of GTP on that particular adenylate cyclase preparation. 5. No evidence of tissue or species specificity was found, as cytosols stimulated adenylate cyclase from their own and unrelated tissues to the same degree. 6. In the human platelet, the inclusion of the cytosol in the assay of adenylate cyclase increased the rate of enzyme activity in response to stimulation by prostaglandin E1 without affecting the amount of prostaglandin E1 required for half-maximal stimulation or the characteristics of enzyme activation by prostaglandin E. PMID:7396869

  15. Who Will Present It during the Broadcast? A Case Study at a Daily Activity Centre

    ERIC Educational Resources Information Center

    Reichenberg, Monica

    2016-01-01

    The present study is an investigation of a daily activity centre (DA). The overall aim was to build a grounded theory that could explain why this particular DA deviated from the norms of Swedish group homes and DAs described in previous studies. These studies have suggested that the staff stuck to old routines, such as letting the participants…

  16. Integrating Functional Neuroimaging and Human Operant Research: Brain Activation Correlated with Presentation of Discriminative Stimuli

    ERIC Educational Resources Information Center

    Schlund, Michael W.; Cataldo, Michael F.

    2005-01-01

    Results of numerous human imaging studies and nonhuman neurophysiological studies on "reward" highlight a role for frontal, striatal, and thalamic regions in operant learning. By integrating operant and functional neuroimaging methodologies, the present investigation examined brain activation to two types of discriminative stimuli correlated with…

  17. Bubble Festival: Presenting Bubble Activities in a Learning Station Format. Teacher's Guide.

    ERIC Educational Resources Information Center

    Barber, Jacqueline; Willard, Carolyn

    This learning station guide adapts the Bubble Festival, an all-school event, for individual classrooms. It presents students with a variety of different challenges at learning stations set up around the classroom. The activities are student-centered and involve open-ended investigations. Also included are ways to extend students' experiences at…

  18. Antioxidant activity of carnosine, homocarnosine, and anserine present in muscle and brain.

    PubMed Central

    Kohen, R; Yamamoto, Y; Cundy, K C; Ames, B N

    1988-01-01

    Carnosine, homocarnosine, and anserine are present in high concentrations in the muscle and brain of many animals and humans. However, their exact function is not clear. The antioxidant activity of these compounds has been examined by testing their peroxyl radical-trapping ability at physiological concentrations. Carnosine, homocarnosine, anserine, and other histidine derivatives all showed antioxidant activity. All of these compounds showing peroxyl radical-trapping activity were also electrochemically active as reducing agents in cyclic voltammetric measurements. Furthermore, carnosine inhibited the oxidative hydroxylation of deoxyguanosine induced by ascorbic acid and copper ions. Other roles of carnosine, such as chelation of metal ions, quenching of singlet oxygen, and binding of hydroperoxides, are also discussed. The data suggest a role for these histidine-related compounds as endogenous antioxidants in brain and muscle. PMID:3362866

  19. Behavior Change Techniques Present in Wearable Activity Trackers: A Critical Analysis

    PubMed Central

    Mercer, Kathryn; Li, Melissa; Giangregorio, Lora; Burns, Catherine

    2016-01-01

    Background Wearable activity trackers are promising as interventions that offer guidance and support for increasing physical activity and health-focused tracking. Most adults do not meet their recommended daily activity guidelines, and wearable fitness trackers are increasingly cited as having great potential to improve the physical activity levels of adults. Objective The objective of this study was to use the Coventry, Aberdeen, and London-Refined (CALO-RE) taxonomy to examine if the design of wearable activity trackers incorporates behavior change techniques (BCTs). A secondary objective was to critically analyze whether the BCTs present relate to known drivers of behavior change, such as self-efficacy, with the intention of extending applicability to older adults in addition to the overall population. Methods Wearing each device for a period of 1 week, two independent raters used CALO-RE taxonomy to code the BCTs of the seven wearable activity trackers available in Canada as of March 2014. These included Fitbit Flex, Misfit Shine, Withings Pulse, Jawbone UP24, Spark Activity Tracker by SparkPeople, Nike+ FuelBand SE, and Polar Loop. We calculated interrater reliability using Cohen's kappa. Results The average number of BCTs identified was 16.3/40. Withings Pulse had the highest number of BCTs and Misfit Shine had the lowest. Most techniques centered around self-monitoring and self-regulation, all of which have been associated with improved physical activity in older adults. Techniques related to planning and providing instructions were scarce. Conclusions Overall, wearable activity trackers contain several BCTs that have been shown to increase physical activity in older adults. Although more research and development must be done to fully understand the potential of wearables as health interventions, the current wearable trackers offer significant potential with regard to BCTs relevant to uptake by all populations, including older adults. PMID:27122452

  20. Alveolar corticotomy: a new surgical approach based on bone activation: principle and protocol.

    PubMed

    Petitbois, Renaud; Scortecci, Gérard

    2012-12-01

    Alveolar corticotomy has proven effective in shortening orthodontic treatments in adults. A new non-invasive and flapless surgical approach has, however, yielded the same results. This technique, based on prior osteogenic alveoli preparation, entails neither anatomical risk nor post-op pain. The present article describes this new protocol and uses a case report to illustrate it. PMID:23164922

  1. Brain activation to briefly presented emotional words: effects of stimulus awareness.

    PubMed

    Hoffmann, Marius; Mothes-Lasch, Martin; Miltner, Wolfgang H R; Straube, Thomas

    2015-02-01

    It is unknown to what extent briefly presented emotional words can be processed without awareness. By means of two independent functional magnetic resonance imaging studies, using either a block or an event-related design, we investigated brain activation to very briefly presented threat related and neutral words during two backward masking conditions (with and without gap between target and mask). In both experiments, emotional words were perceived during the supraliminal "with gap" condition, but they were not recognized during the subliminal "without gap" condition, as indicated by signal detection theory analysis. Imaging results of both experiments showed increased activation of the amygdala, the medial prefrontal cortex and language-processing cortical areas to negative versus neutral words during supraliminal but not subliminal conditions. These results suggest that even very briefly presented emotional words are capable of triggering increased cortical and subcortical processing; however, only when awareness of these stimuli is given. PMID:25324170

  2. Unidirectional Mechanical Amplification as a Design Principle for an Active Microphone

    NASA Astrophysics Data System (ADS)

    Reichenbach, Tobias; Hudspeth, A. J.

    2011-04-01

    Amplification underlies the operation of many biological and engineering systems. Simple electrical, optical, and mechanical amplifiers are reciprocal: the backward coupling of the output to the input equals the forward coupling of the input to the output. Unidirectional amplifiers that occur often in electrical and optical systems are special nonreciprocal devices in which the output does not couple back to the input even though the forward coupling persists. Here we propose a scheme for unidirectional mechanical amplification that we utilize to construct an active microphone. We show that amplification improves the microphone’s threshold for detecting weak signals and that unidirectionality prevents distortion.

  3. Driving Toward Guiding Principles

    PubMed Central

    Buckovich, Suzy A.; Rippen, Helga E.; Rozen, Michael J.

    1999-01-01

    As health care moves from paper to electronic data collection, providing easier access and dissemination of health information, the development of guiding privacy, confidentiality, and security principles is necessary to help balance the protection of patients' privacy interests against appropriate information access. A comparative review and analysis was done, based on a compilation of privacy, confidentiality, and security principles from many sources. Principles derived from ten identified sources were compared with each of the compiled principles to assess support level, uniformity, and inconsistencies. Of 28 compiled principles, 23 were supported by at least 50 percent of the sources. Technology could address at least 12 of the principles. Notable consistencies among the principles could provide a basis for consensus for further legislative and organizational work. It is imperative that all participants in our health care system work actively toward a viable resolution of this information privacy debate. PMID:10094065

  4. Hypertension and Diabetes Mellitus: A Preliminary South African Health Promotion Activity Using Service-Learning Principles.

    PubMed

    Srinivas, Sunitha C; Paphitis, Sharli Anne

    2016-06-01

    A marked increase in the chronic non-communicable diseases such as hypertension and diabetes mellitus in the South African population is in concert with global trends. A health promotion activity carried out by pharmacy students for school learners during the Sasol National Festival of Science and Technology (SciFest) in South Africa was used as a service-learning opportunity. Pilot tested quizzes on hypertension and diabetes were used to determine the level of knowledge of attendees before and after taking the computer based quiz. Posters, information leaflets and interactive models on these two conditions were also used to reach out to the larger population. Of the 203 participants for the hypertension quiz, 169 completed both the pre- and post-intervention quizzes. Similarly, 86 of the 104 participants for the diabetes quiz, completed both the pre- and post-intervention quizzes. The results show that the post-intervention quiz resulted in a significant increase in the scores from 78.2 to 85.6 % in the case of Hypertension while a marginal increase from 94.2 to 95.5 % was obtained in the case of diabetes. The knowledge of the SciFest attendees with regard to both conditions is above average and improved further after the educational intervention. Health promotion activities which include interactive educational methods and culturally appropriate materials carried out by pharmacy students during service-learning courses are important for improving the awareness on the prevention of these chronic health conditions. Heath promotion service-learning courses can assist in addressing the health care gaps which arise because of a lack of co-ordinated efforts between NGO's and local Government to address the prevention and management of non-communicable diseases such as hypertension and diabetes mellitus. PMID:26659854

  5. Healthcare Financial Management Association, Principles and Practices Board. Statement no. 15: Valuation and financial statement presentation of charity service and bad debts by institutional healthcare providers.

    PubMed

    1993-02-01

    Principles and Practices Board (P&P Board) Statement No. 2, issued in 1978, provided a basis for differentiating between charity service and bad debts. The statement acknowledged that, while the differentiation was helpful, the financial accounting and reporting of charity service and bad debts were the same. In 1990, the American Institute of Certified Public Accountants (AICPA) published (after review and approval by the Financial Accounting Standards Board and the Governmental Accounting Standards Board) an extensive revision of the guide titled "Audits of Providers of Health Care Services." The revised guide substantially changed the reporting of bad debts and eliminated charity service from revenue. Disclosure of the entity's policy for providing charity service and the level of charity service provided is required by the revised guide. The P&P Board decided that a substantive revision of its Statement No. 2 was required to bring it into conformity with the revised guide and to provide direction on implementation of the revised guide's requirements. This statement supersedes Statement No. 2 and deals with the same issues, including bad debts. PMID:10145753

  6. The Self-Presentation Motives for Physical Activity Questionnaire: Instrument Development and Preliminary Construct Validity Evidence.

    PubMed

    Howle, Timothy C; Dimmock, James A; Whipp, Peter R; Jackson, Ben

    2015-06-01

    With the aim of advancing the literature on impression management in physical activity settings, we developed a theoretically derived 2 by 2 instrument that was designed to measure different types of context-specific self-presentation motives. Following item generation and expert review (Study 1), the instrument was completed by 206 group exercise class attendees (Study 2) and 463 high school physical education students (Study 3). Our analyses supported the intended factor structure (i.e., reflecting acquisitive-agentic, acquisitive-communal, protective-agentic, and protective-communal motives). We found some support for construct validity, and the self-presentation motives were associated with variables of theoretical and applied interest (e.g., impression motivation and construction, social anxiety, social and achievement goals, efficacy beliefs, engagement). Taken together, the results indicate that the Self-presentation Motives for Physical Activity Questionnaire (SMPAQ) may be useful for measuring various types of self-presentation motives in physical activity settings. PMID:26265337

  7. STAT2 Is Required for TLR-Induced Murine Dendritic Cell Activation and Cross-Presentation.

    PubMed

    Xu, Jun; Lee, Michael H; Chakhtoura, Marita; Green, Benjamin L; Kotredes, Kevin P; Chain, Robert W; Sriram, Uma; Gamero, Ana M; Gallucci, Stefania

    2016-07-01

    TLR-stimulated cross-presentation by conventional dendritic cells (cDCs) is important in host defense and antitumor immunity. We recently reported that cDCs lacking the type I IFN signaling molecule STAT2 are impaired in cross-presenting tumor Ags to CD8(+) T cells. To investigate how STAT2 affects cross-presentation, we determined its requirements for dendritic cell activation. In this study, we report that STAT2 is essential for the activation of murine female cDCs upon TLR3, -4, -7, and -9 stimulation. In response to various TLR ligands, Stat2(-/-) cDCs displayed reduced expression of costimulatory molecules and type I IFN-stimulated genes. The cDC responses to exogenous IFN-α that we evaluated required STAT2 activation, indicating that the canonical STAT1-STAT2 heterodimers are the primary signaling transducers of type I IFNs in cDCs. Interestingly, LPS-induced production of IL-12 was STAT2 and type I IFN receptor (IFNAR) dependent, whereas LPS-induced production of TNF-α and IL-6 was STAT2 and IFNAR independent, suggesting a specific role of the IFNAR-STAT2 axis in the stimulation of proinflammatory cytokines by LPS in cDCs. In contrast, R848- and CpG-induced cytokine production was less influenced by the IFNAR-STAT2 axis. Short kinetics and IFNAR blockade studies showed that STAT2 main function is to transduce signals triggered by autocrine type I IFNs. Importantly, Stat2(-/-) cDCs were deficient in cross-presenting to CD8(+) T cells in vitro upon IFN-α, CpG, and LPS stimulation, and also in cross-priming and licensing cytotoxic T cell killers in vivo. We conclude that STAT2 plays a critical role in TLR-induced dendritic cell activation and cross-presentation, and thus is vital in host defense. PMID:27233962

  8. Antibacterial and Anti-inflammatory Activities of Ppc-1, Active Principle of the Cellular Slime Mold Polysphondylium pseudo-candidum.

    PubMed

    Azelmat, Jabrane; Fiorito, Serena; Genovese, Salvatore; Epifano, Francesco; Grenier, Daniel

    2015-01-01

    The diisopentenyloxy quinolobactin derivative 3-methylbut-2-enyl-4-methoxy-8-[(3-methylbut-2-enyl)oxy] quinoline-2-carboxylate, also named as Ppc-1, has been initially isolated from the fruiting bodies of the cellular slime mold Polysphondylium pseudo-candidum. Given that few data are available in the literature concerning the biological properties of this compound, this study was undertaken to evaluate its antibacterial and anti-inflammatory properties. Ppc-1 exerted antibacterial activity on the Gram negative periodontopathogen Porphyromonas gingivalis, while it had no such effect on the other bacterial species tested. The antibacterial activity of Ppc-1 appeared to result from its ability to permeate the cell membrane. Using the U937-3xκB-LUC human monocytic cell line, Ppc-1 was found to dose-dependently inhibit the lipopolysaccharide-induced NF-κB activation, a signaling pathway that has been associated with inflammatory mediator secretion. In conclusion, Ppc-1, by exhibiting a dual mode of action including antibacterial and anti-inflammatory activities, may represent a promising targeted therapeutic agent for periodontal diseases. PMID:25925558

  9. Glycyrrhetinic acid, the active principle of licorice, can reduce the thickness of subcutaneous thigh fat through topical application.

    PubMed

    Armanini, Decio; Nacamulli, Davide; Francini-Pesenti, Francesco; Battagin, Giuliana; Ragazzi, Eugenio; Fiore, Cristina

    2005-07-01

    Cortisol is involved in the distribution and deposition of fat, and its action is regulated by the activity of 11beta-hydroxysteroid dehydrogenase. Glycyrrhetinic acid, the active principle of licorice root, blocks 11beta-hydroxysteroid dehydrogenase type 1, thus reducing the availability of cortisol at the level of adipocytes. We evaluated the effect of topical application of a cream containing glycyrrhetinic acid in the thickness of fat at the level of the thigh. Eighteen healthy women (age range 20-33 years) with normal BMI were randomly allocated to treatment, at the level of the dominant thigh, with a cream containing 2.5% glycyrrhetinic acid (n=9) or with a placebo cream containing the excipients alone (n=9). Before and after 1 month of treatment both the circumference and the thickness of the superficial fat layer of the thighs (by ultrasound analysis) were measured. The circumference and the thickness of the superficial fat layer were significantly reduced in comparison to the controlateral untreated thigh and to control subjects treated with the placebo cream. No changes were observed in blood pressure, plasma renin activity, plasma aldosterone or cortisol. The effect of glycyrrhetinic acid on the thickness of subcutaneous fat was likely related to a block of 11beta-hydroxysteroid dehydrogenase type 1 at the level of fat cells; therefore, glycyrrhetinic acid could be effectively used in the reduction of unwanted local fat accumulation. PMID:15894038

  10. A novel approach for reliable detection of cathepsin S activities in mouse antigen presenting cells.

    PubMed

    Steimle, Alex; Kalbacher, Hubert; Maurer, Andreas; Beifuss, Brigitte; Bender, Annika; Schäfer, Andrea; Müller, Ricarda; Autenrieth, Ingo B; Frick, Julia-Stefanie

    2016-05-01

    Cathepsin S (CTSS) is a eukaryotic protease mostly expressed in professional antigen presenting cells (APCs). Since CTSS activity regulation plays a role in the pathogenesis of various autoimmune diseases like multiple sclerosis, atherosclerosis, Sjögren's syndrome and psoriasis as well as in cancer progression, there is an ongoing interest in the reliable detection of cathepsin S activity. Various applications have been invented for specific detection of this enzyme. However, most of them have only been shown to be suitable for human samples, do not deliver quantitative results or the experimental procedure requires technical equipment that is not commonly available in a standard laboratory. We have tested a fluorogen substrate, Mca-GRWPPMGLPWE-Lys(Dnp)-DArg-NH2, that has been described to specifically detect CTSS activities in human APCs for its potential use for mouse samples. We have modified the protocol and thereby offer a cheap, easy, reproducible and quick activity assay to detect CTSS activities in mouse APCs. Since most of basic research on CTSS is performed in mice, this method closes a gap and offers a possibility for reliable and quantitative CTSS activity detection that can be performed in almost every laboratory. PMID:26899824

  11. Label free detection of optogenetically stimulated cellular activity by low coherence interferometry (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Satpathy, Sarmishtha; Batabyal, Subrata; Dave, Digant P.; Mohanty, Samarendra K.

    2016-03-01

    Detecting cellular activity in sub-millisecond timescale and micrometer resolution without using invasive means has been a long standing goal in the study of cellular networks. Here, we have employed phase sensitive low coherence interferometry for detecting optogenetically stimulated activity of cells. Nanoscale changes in optical path length (due to change in refractive index and changes in cell thickness) occur when cells are activated, which we aim to detect by phase sensitive low coherence interferometry. A low coherence interferometry and patch-clamp electrophysiology systems were integrated with an inverted fluorescence microscope. Blue laser beam was coupled to the electrophysiology-interferometric detection system for optogenetic stimulation. The phase-sensitive measurements were carried out on Channelrhodopsin-2 sensitized cells (identified by YFP fluorescence) as well as control cells in reflection mode for different intensities and exposures of optogenetic stimulation beam. This method offers good temporal and spatial resolution without using exogenous labeling. Results of studies on all optical stimulation and detection of cellular activity will be presented. Interpretation of the optical activity signals will be discussed in context with changes in cell physiology during stimulation. We will also discuss the potential sources of various artifacts in optical/electrical detection of cellular activity during optical stimulation.

  12. Visual presentation of phobic stimuli: amygdala activation via an extrageniculostriate pathway?

    PubMed

    Goossens, Liesbet; Schruers, Koen; Peeters, Ronald; Griez, Eric; Sunaert, Stefan

    2007-07-15

    In the present study, event-related functional magnetic resonance imaging (fMRI) was used to examine the neural correlates of phobic fear by exposing spider phobic subjects to a visual presentation of spiders. In contrast to control subjects, spider phobics showed significantly increased activation in the amygdala and the pulvinar nucleus of the thalamus on the basis of region of interest (ROI) analysis. Furthermore, voxelwise analysis revealed increased activation related to phobia-specific pictures bilaterally in the anterior cingulate cortex, the left insular cortex and bilaterally in the supplementary motor area. These findings confirm the involvement of the amygdala in the processing of phobia-relevant stimuli as found earlier in a recent study. Moreover, the thalamus findings support the involvement of an extrageniculostriate pathway in the process of phobic fear. PMID:17499485

  13. Tales from the Dark Side: Teacher Professional Development , Support , Activities, Student Research & Presentations

    NASA Astrophysics Data System (ADS)

    Walker, C. E.; Pompea, S. M.

    2013-12-01

    In a partnership last Spring with Arizona Public Service, the National Optical Astronomy Observatory (NOAO) created the 'Dark-Skies Energy Education Program: Energy Awareness for a Sustainable Future'. In this program, experienced science and technology education specialists from NOAO led 2 one-day professional development workshops for thirteen 6th grade teachers on dark skies and energy education. The workshops focused on three foundational, scaffolding activities and a final student research project. This in turn culminated in a Family Science Night where students presented their projects. In between these events, our NOAO team provided support for teachers through real-time video conferencing using FaceTime. In addition to the professional development, each teacher received a kit full of resource materials to perform the activities and research project. The kit was at no cost to the teacher, school, or district. Each kit contained the latest version of a tablet, which was used to facilitate communication and support for the teachers, as well as provide all the program's written teaching materials. The activities are in accordance with state, Common Core and Next Generation Science Standards. Our NOAO instructors gave firsthand experiences on how best to use these materials in a classroom or public setting. They also discussed opportunities on how they can incorporate, adapt and expand upon the activities and research projects in the classroom. Evaluation reports from the program's independent evaluator showed that the students enjoyed learning from the three foundational activities and research projects. The project presentations by the Yuma students were outstanding in their creativity, level of effort, and scientific accuracy. To summarize the evaluations, significant changes in knowledge and attitude were made with the teachers and students (from one-on-one interviews and surveys), but behavioral changes (albeit only over a semester) seemed minimal. The AGU

  14. Achievements of the Armenian Astronomy and the Present Activities of the Armenian Astronomical Society

    NASA Astrophysics Data System (ADS)

    Mickaelian, A. M.

    2014-10-01

    A report is given on the achievements of the Armenian astronomy during the last years and on the present activities of the Armenian Astronomical Society (ArAS). ArAS membership, ArAS electronic newsletters (ArASNews), ArAS webpage, international collaboration, Armenian Virtual Observatory (ArVO), membership in international organizations, grants, prizes, meetings, summer schools, astronomical Olympiads, other matters related to astronomical education, archaeoastronomy, astronomy outreach and ArAS further projects are discussed.

  15. Quantum dot based enzyme activity sensors present deviations from Michaelis-Menten kinetic model

    NASA Astrophysics Data System (ADS)

    Díaz, Sebastián. A.; Brown, Carl W.; Malanoski, Anthony P.; Oh, Eunkeu; Susumu, Kimihiro; Medintz, Igor L.

    2016-03-01

    Nanosensors employing quantum dots (QDs) and enzyme substrates with fluorescent moieties offer tremendous promise for disease surveillance/diagnostics and as high-throughput co-factor assays. Advantages of QDs over other nanoscaffolds include their small size and inherent photochemical properties such as size tunable fluorescence, ease in attaching functional moieties, and resistance to photobleaching. These properties make QDs excellent Förster Resonance Energy Transfer (FRET) donors; well-suited for rapid, optical measurement applications. We report enzyme sensors designed with a single FRET donor, the QD donor acting as a scaffold to multiple substrates or acceptors. The QD-sensor follows the concrete activity of the enzyme, as compared to the most common methodologies that quantify the enzyme amount or its mRNA precursor. As the sensor reports on the enzyme activity in real-time we can actively follow the kinetics of the enzyme. Though classic Michaelis-Menten (MM) parameters can be obtained to describe the activity. In the course of these experiments deviations, both decreasing and increasing the kinetics, from the common MM model were observed upon close examinations. From these observations additional experiments were undertaken to understand the varying mechanisms. Different enzymes can present different deviations depending on the chosen target, e.g. trypsin appears to present a positive hopping mechanism while collagenase demonstrates a QD caused reversible inhibition.

  16. Principles of activation and permeation in an anion-selective Cys-loop receptor.

    PubMed

    Hibbs, Ryan E; Gouaux, Eric

    2011-06-01

    Fast inhibitory neurotransmission is essential for nervous system function and is mediated by binding of inhibitory neurotransmitters to receptors of the Cys-loop family embedded in the membranes of neurons. Neurotransmitter binding triggers a conformational change in the receptor, opening an intrinsic chloride channel and thereby dampening neuronal excitability. Here we present the first three-dimensional structure, to our knowledge, of an inhibitory anion-selective Cys-loop receptor, the homopentameric Caenorhabditis elegans glutamate-gated chloride channel α (GluCl), at 3.3 Å resolution. The X-ray structure of the GluCl-Fab complex was determined with the allosteric agonist ivermectin and in additional structures with the endogenous neurotransmitter L-glutamate and the open-channel blocker picrotoxin. Ivermectin, used to treat river blindness, binds in the transmembrane domain of the receptor and stabilizes an open-pore conformation. Glutamate binds in the classical agonist site at subunit interfaces, and picrotoxin directly occludes the pore near its cytosolic base. GluCl provides a framework for understanding mechanisms of fast inhibitory neurotransmission and allosteric modulation of Cys-loop receptors. PMID:21572436

  17. Biomimetic Protein Nanoparticles Facilitate Enhanced Dendritic Cell Activation and Cross-Presentation

    PubMed Central

    Molino, Nicholas M.; Anderson, Amanda K. L.; Nelson, Edward L.; Wang, Szu-Wen

    2013-01-01

    Many current cancer vaccine strategies suffer from the inability to mount a CD8 T cell response that is strong enough to overcome the low immunogenicity of tumors. Viruses naturally possess the sizes, geometries, and physical properties for which the immune system has evolved to recognize, and mimicking those properties with nanoparticles can produce robust platforms for vaccine design. Using the non-viral E2 core of pyruvate dehydrogenase, we have engineered a viral-mimicking vaccine platform capable of encapsulating dendritic cell (DC)-activating CpG molecules in an acid-releasable manner and displaying MHC I-restricted SIINFEKL peptide epitopes. Encapsulated CpG activated bone marrow-derived DCs at a 25- fold lower concentration in vitro when delivered with the E2 nanoparticle than with unbound CpG alone. Combining CpG and SIINFEKL within a single multifunctional particle induced ~ 3-fold greater SIINFEKL display on MHC I by DCs over unbound peptide. Importantly, combining CpG and SIINFEKL to the E2 nanoparticle for simultaneous temporal and spatial delivery to DCs showed increased and prolonged CD8 T cell activation, relative to free peptide or peptide-bound E2. By co-delivering peptide epitopes and CpG activator in a particle of optimal DC-uptake size, we demonstrate the ability of a non-infectious protein nanoparticle to mimic viral properties and facilitate enhanced DC activation and cross-presentation. PMID:24090491

  18. First-Principles Quantum Dynamics of Singlet Fission: Coherent versus Thermally Activated Mechanisms Governed by Molecular π Stacking.

    PubMed

    Tamura, Hiroyuki; Huix-Rotllant, Miquel; Burghardt, Irene; Olivier, Yoann; Beljonne, David

    2015-09-01

    Singlet excitons in π-stacked molecular crystals can split into two triplet excitons in a process called singlet fission that opens a route to carrier multiplication in photovoltaics. To resolve controversies about the mechanism of singlet fission, we have developed a first principles nonadiabatic quantum dynamical model that reveals the critical role of molecular stacking symmetry and provides a unified picture of coherent versus thermally activated singlet fission mechanisms in different acenes. The slip-stacked equilibrium packing structure of pentacene derivatives is found to enhance ultrafast singlet fission mediated by a coherent superexchange mechanism via higher-lying charge transfer states. By contrast, the electronic couplings for singlet fission strictly vanish at the C(2h) symmetric equilibrium π stacking of rubrene. In this case, singlet fission is driven by excitations of symmetry-breaking intermolecular vibrations, rationalizing the experimentally observed temperature dependence. Design rules for optimal singlet fission materials therefore need to account for the interplay of molecular π-stacking symmetry and phonon-induced coherent or thermally activated mechanisms. PMID:26382701

  19. First-Principles Quantum Dynamics of Singlet Fission: Coherent versus Thermally Activated Mechanisms Governed by Molecular π Stacking

    NASA Astrophysics Data System (ADS)

    Tamura, Hiroyuki; Huix-Rotllant, Miquel; Burghardt, Irene; Olivier, Yoann; Beljonne, David

    2015-09-01

    Singlet excitons in π -stacked molecular crystals can split into two triplet excitons in a process called singlet fission that opens a route to carrier multiplication in photovoltaics. To resolve controversies about the mechanism of singlet fission, we have developed a first principles nonadiabatic quantum dynamical model that reveals the critical role of molecular stacking symmetry and provides a unified picture of coherent versus thermally activated singlet fission mechanisms in different acenes. The slip-stacked equilibrium packing structure of pentacene derivatives is found to enhance ultrafast singlet fission mediated by a coherent superexchange mechanism via higher-lying charge transfer states. By contrast, the electronic couplings for singlet fission strictly vanish at the C2 h symmetric equilibrium π stacking of rubrene. In this case, singlet fission is driven by excitations of symmetry-breaking intermolecular vibrations, rationalizing the experimentally observed temperature dependence. Design rules for optimal singlet fission materials therefore need to account for the interplay of molecular π -stacking symmetry and phonon-induced coherent or thermally activated mechanisms.

  20. Direct method of three-dimensional imaging using the multiple-wavelength range-gated active imaging principle.

    PubMed

    Matwyschuk, Alexis

    2016-05-10

    The tomography executed with mono-wavelength active imaging systems uses the recording of several images to restore a three-dimensional (3D) scene. Thus, in order to show the depth in the scene, a different color is attributed to each recorded image. Therefore, the 3D restoration depends on the video frame rate of the camera. By using a multiple-wavelength range-gated active imaging system, it is possible to restore the 3D scene directly in a single image at the moment of recording with a video camera. Each emitted light pulse with a different wavelength corresponds to a visualized zone at a different distance in the scene. The camera shutter opens just once during the emission of light pulses with the different wavelengths. Thus, the restoration can be executed in real time with regard to the video frame rate of the camera. From an analytical model and from a graphical approach, we demonstrated the feasibility of this new method of 3D restoration. The non-overlapping conditions between two consecutive visualized zones are analyzed. The experimental test results confirm these different conditions and validate the theoretical principle to directly restore the 3D scene in a color image with a multiple-wavelength laser source, an RGB filter, and a triggerable intensified camera. PMID:27168293

  1. In Vitro Inhibitory Effect of Clove Essential Oil and Its Two Active Principles on Tooth Decalcification by Apple Juice

    PubMed Central

    Marya, Charu M.; Satija, Gunjan; J., Avinash; Nagpal, Ruchi; Kapoor, Rohtash; Ahmad, Aijaz

    2012-01-01

    The dental erosion or decalcification of enamel is a significant clinical problem. Apple acidic beverages are thought to increase the potential for dental erosion. The purpose of this in vitro study was to investigate the effect of clove essential oil (CEO) and its active principles on tooth decalcification of apple juices. On GC-MS analysis, CEO showed a high content of eugenol (58.29%) and eugenyl acetate (19.10%). Teeth specimens were randomly divided into 5 treatment groups: control, CEO, eugenol, eugenyl-acetate, and fluoride. The specimens were exposed for 24 h and were analyzed for calcium contents using Inductively Coupled Plasma with Optical Emission Spectroscopy (ICP-OES). Data were analyzed using student t-test (P < 0.05). CEO, eugenol, and eugenyl-acetate significantly decreased the decalcification of tooth by the apple juice to only 17, 24, and 21 mgL−1, respectively. Hemolytic activity on human erythrocytes was studied to exclude the possibility of further associated cytotoxicity. It was observed that the CEO and its two lead molecules inhibit the decalcification and/or promote the remineralization caused by the apple juices. The effect of the test compounds appears to be distinct like that of fluoride treatment. CEO may, therefore, serve to be a promising adjunct to fluoride in the treatment of root caries during minimally invasive therapy. PMID:22997520

  2. Paralysis as a Presenting Symptom of Hyperthyroidism in an Active Duty Soldier.

    PubMed

    Jennette, John; Tauferner, Dustin

    2015-01-01

    Thyrotoxic periodic paralysis (TPP) is an endocrine disorder presenting with proximal motor weakness, typically greatest in the lower extremities, hypokalemia, and signs or laboratory findings consistent with hyperthyroidism. The incidence of TPP is highest in Asian males. This is a case report of a 30-year-old male active duty Soldier who presented to the emergency department complaining of several recent episodes of lower extremity paralysis. The patient underwent a workup which included serum and cerebrospinal fluid studies, and was found to be hypokalemic and hyperthyroid. Following consultation with neurology, the patient was admitted to the medicine service and treated for thyrotoxic periodic paralysis with potassium replacement and treatment of his hyperthyroidism. Since achieving a euthyroid state, he has had no recurrences of TPP. This disease should be considered in patients presenting with symmetric motor weakness and hypokalemia, whether or not symptoms of hyperthyroidism are elicited during the review of systems. PMID:26606408

  3. Regulation of protein synthesis and autophagy in activated dendritic cells: implications for antigen processing and presentation.

    PubMed

    Argüello, Rafael J; Reverendo, Marisa; Gatti, Evelina; Pierre, Philippe

    2016-07-01

    Antigenic peptides presented in the context of major histocompatibility complex (MHC) molecules originate from the degradation of both self and non-self proteins. T cells can therefore recognize at the surface of surveyed cells, the self-peptidome produced by the cell itself (mostly inducing tolerance) or immunogenic peptides derived from exogenous origins. The initiation of adaptive immune responses by dendritic cells (DCs), through the antigenic priming of naïve T cells, is associated to microbial pattern recognition receptors engagement. Activation of DCs by microbial product or inflammatory cytokines initiates multiple processes that maximize DC capacity to present exogenous antigens and stimulate T cells by affecting major metabolic and membrane traffic pathways. These include the modulation of protein synthesis, the regulation of MHC and co-stimulatory molecules transport, as well as the regulation of autophagy, that, all together promote exogenous antigen presentation while limiting the display of self-antigens by MHC molecules. PMID:27319340

  4. Dried extracts of Encholirium spectabile (Bromeliaceae) present antioxidant and photoprotective activities in vitro

    PubMed Central

    de Oliveira, Raimundo Gonçalves; Souza, Grasielly Rocha; Guimarães, Amanda Leite; de Oliveira, Ana Paula; Silva Morais, Amanda Caroline; da Cruz Araújo, Edigênia Cavalcante; Nunes, Xirley Pereira; Almeida, Jackson Roberto Guedes da Silva

    2013-01-01

    The antioxidant and photoprotective activities of dried extracts from the leaves of Encholirium spectabile were investigated. It was also evaluated the total phenolic and flavonoid contents by the Folin–Ciocalteu and aluminum chloride methods, respectively. Antioxidant activities of the extracts were evaluated by using of 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging and β-carotene–linoleic acid bleaching and compared with ascorbic acid, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) used as reference compounds. The photoprotective effect was evaluated by the spectrophotometric method. The most significant total phenolic and flavonoid contents was of 188.50 ± 27.50 mg of gallic acid equivalent/g and 129.70 ± 4.59 mg of catechin equivalent/g, respectively, for chloroform fraction (Es-CHCl3). The Es-CHCl3 also presented the best antioxidant activity (IC50 25.35 ± 4.35 μg/ml) for DPPH scavenging. The ethanol extract (Es-EtOH), Es-CHCl3 and the fraction ethyl acetate (Es-AcOEt) showed characteristic absorption bands in regions UVB and UVA in a concentration-dependent manner. Es-CHCl3 presented the highest sun protection factor SPF (8.89 ± 2.11). It shows the possibility to use this extract as sunscreen in pharmaceutical preparations. PMID:24396251

  5. UDP-glucuronosyltransferase 1a enzymes are present and active in the mouse blastocyst.

    PubMed

    Collier, Abby C; Yamauchi, Yasuhiro; Sato, Brittany L M; Rougée, Luc R A; Ward, Monika A

    2014-11-01

    The UDP-glucuronosyltransferase (UGT) enzymes are critical for regulating nutrients, hormones, and endobiotics, as well as for detoxifying xenobiotics. Human and murine fetuses are known to express glucuronidation enzymes, but there are currently no data prior to implantation. Here we addressed this gap in knowledge and tested whether Ugt enzymes are already present in preimplantation-stage embryos. Blastocysts were obtained after in vitro fertilization with gametes from B6D2F1 hybrid mice and from embryo culture. Protein expression and localization were determined using pan-specific UGT1A and UGT2B, as well as anti-human isoform-specific antibodies. Immunofluorescence analysis showed that blastocysts expressed Ugt1a globally, in the cytoplasm and nuclei of all of the cells. Western blots demonstrated the presence of Ugt1a6 but not Ugt1a1, Ugt1a3, Ugt1a4, or Ugt1a9. The Ugt2b proteins were not detected by either assay. The level of Ugt activity in murine blastocysts was comparable with that of the adult human liver (per milligram of protein), but the activity of β-glucuronidase, an Ugt-partnering enzyme responsible for substrate regeneration, was lower. Altogether, these data confirm that Ugt1a proteins are present and active in preimplantation murine embryos and point to a potential role for these proteins in implantation and early embryonic and fetal development. PMID:25200869

  6. UDP-Glucuronosyltransferase 1a Enzymes Are Present and Active in the Mouse Blastocyst

    PubMed Central

    Yamauchi, Yasuhiro; Sato, Brittany L.M.; Rougée, Luc R.A.; Ward, Monika A.

    2014-01-01

    The UDP-glucuronosyltransferase (UGT) enzymes are critical for regulating nutrients, hormones, and endobiotics, as well as for detoxifying xenobiotics. Human and murine fetuses are known to express glucuronidation enzymes, but there are currently no data prior to implantation. Here we addressed this gap in knowledge and tested whether Ugt enzymes are already present in preimplantation-stage embryos. Blastocysts were obtained after in vitro fertilization with gametes from B6D2F1 hybrid mice and from embryo culture. Protein expression and localization were determined using pan-specific UGT1A and UGT2B, as well as anti-human isoform-specific antibodies. Immunofluorescence analysis showed that blastocysts expressed Ugt1a globally, in the cytoplasm and nuclei of all of the cells. Western blots demonstrated the presence of Ugt1a6 but not Ugt1a1, Ugt1a3, Ugt1a4, or Ugt1a9. The Ugt2b proteins were not detected by either assay. The level of Ugt activity in murine blastocysts was comparable with that of the adult human liver (per milligram of protein), but the activity of β-glucuronidase, an Ugt-partnering enzyme responsible for substrate regeneration, was lower. Altogether, these data confirm that Ugt1a proteins are present and active in preimplantation murine embryos and point to a potential role for these proteins in implantation and early embryonic and fetal development. PMID:25200869

  7. Modeling adsorption rate of organic micropollutants present in landfill leachates onto granular activated carbon.

    PubMed

    Ocampo-Pérez, Raúl; Abdel daiem, Mahmoud M; Rivera-Utrilla, José; Méndez-Díaz, José D; Sánchez-Polo, Manuel

    2012-11-01

    The overall adsorption rate of single micropollutants present in landfill leachates such as phthalic acid (PA), bisphenol A (BPA), diphenolic acid (DPA), 2,4-dichlorophenoxy-acetic acid (2,4-D), and 4-chloro-2-methylphenoxyacetic acid (MCPA) on two commercial activated carbons was studied. The experimental data obtained were interpreted by using a diffusional model (PVSDM) that considers external mass transport, intraparticle diffusion, and adsorption on an active site. Furthermore, the concentration decay data were interpreted by using kinetics models. Results revealed that PVSDM model satisfactorily fitted the experimental data of adsorption rate on activated carbon. The tortuosity factor of the activated carbons used ranged from 2 to 4. The contribution of pore volume diffusion represented more than 92% of intraparticle diffusion confirming that pore volume diffusion is the controlling mechanism of the overall rate of adsorption and surface diffusion can be neglected. The experimental data were satisfactorily fitted the kinetic models. The second-order kinetic model was better fitted the experimental adsorption data than the first-order model. PMID:22858399

  8. Mammalian peptide isomerase: platypus-type activity is present in mouse heart.

    PubMed

    Koh, Jennifer M S; Chow, Stephanie J P; Crossett, Ben; Kuchel, Philip W

    2010-06-01

    Male platypus (Ornithorhynchus anatinus) venom has a peptidyl aminoacyl L/D-isomerase (hereafter called peptide isomerase) that converts the second amino acid residue in from the N-terminus from the L- to the D-form, and vice versa. A reversed-phase high-performance liquid chromatography (RP-HPLC) assay has been developed to monitor the interconversion using synthetic hexapeptides derived from defensin-like peptide-2 (DLP-2) and DLP-4 as substrates. It was hypothesised that animals other than the platypus would have peptide isomerase with the same substrate specificity. Accordingly, eight mouse tissues were tested and heart was shown to have the activity. This is notable for being the first evidence of a peptide isomerase being present in a higher mammal and heralds finding the activity in man. PMID:20564672

  9. Present-day biogeochemical activities of anaerobic bacteria and their relevance to future exobiological investigations

    USGS Publications Warehouse

    Oremland, R.S.

    1989-01-01

    If the primordial atmosphere was reducing, then the first microbial ecosystem was probably composed of anaerobic bacteria. However, despite the presence of an oxygen-rich atmosphere, anaerobic habitats are important, commonplace components of the Earth's present biosphere. The geochemical activities displayed by these anaerobes impact the global cycling of certain elements (e.g., C, N, S, Fe, Mn, etc.). Methane provides an obvious example of how human-enhanced activities on a global scale can influence the content of a "radiative" (i.e., infrared absorbing) trace gas in the atmosphere. Methane can be oxidized by anaerobic bacteria, but this does not appear to support their growth. Acetylene, however, does support such growth. This may form the basis for future exobiological investigations of the atmospheres of anoxic, hydrocarbon-rich planets like Jupiter and Saturn, as well as the latter's satellite Titan. ?? 1989.

  10. Deciphering the Long-Term Trend of Atlantic Basin Intense Hurricanes: More Active Versus Less Active During the Present Epoch

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    1998-01-01

    During the interval of 1944-1997, 120 intense hurricanes (i.e., those of category 3 or higher on the Saffir-Simpson hurricane damage potential scale) were observed in the Atlantic basin, having an annual frequency of 0-7 events per year, being more active prior to the mid 1960's than thereafter (hence a possible two-state division: more active versus less active), and being preferentially lower during El Nino years as compared to non-El Nino years. Because decadal averages of the frequency of intense hurricanes closely resemble those of average temperature anomalies for northern hemispheric and global standards and of the average temperature at the Armagh Observatory (Northern Ireland), a proxy for climatic change, it is inferred that the long-term trends of the annual frequency of intense hurricanes and temperature may be statistically related. Indeed, on the basis of 4- and 10-yr moving averages, one finds that there exists strong linear associations between the annual frequency of intense hurricanes in the Atlantic basin and temperature (specially, when temperature slightly leads). Because the long-term leading trends of temperature are now decidedly upward, beginning about the mid 1980's, it is inferred that the long-term consequential trends of the annual frequency of intense hurricanes should now also be upward, having begun near 1990, suggesting that a return to the more active state probably has already occurred. However, because of the anomalous El Nino activity of the early to mid 1990's, the switch from the less active to the more active state essentially went unnoticed (a marked increase in the number of intense hurricanes was not observed until the 1995 and 1996 hurricane seasons, following the end of the anomalous El Nino activity). Presuming that a return to the more active state has, indeed, occurred, one expects the number of seasonal intense hurricanes during the present epoch (continuing through about 2012) to usually be higher than average (i

  11. Video and film analysis with correlation tracking and active result presentation (Abstract Only)

    NASA Astrophysics Data System (ADS)

    Rowa, Per

    1990-08-01

    Experience with a turnkey analysis system featuring high resolution video input and display, a modular video disc system and a 16 mm cine film scanner with 2600-point resolution, is presented. Tracking is performed with a high-speed correlation process, requiring no special markers. Software packages for evaluating two and three-dimensional results are interactively accessible. Combining the original image sequence with real-time graphic overlays and active drawing of graphic diagrams, provides for an excellent understanding and documentation of the motion sequences.

  12. European Space Agency detector development for space science: present and future activities

    NASA Astrophysics Data System (ADS)

    Duvet, L.; Bavdaz, M.; Crouzet, P. E.; Nelms, N.; Nowicki-Bringuier, Y. R.; Shortt, B.; Verhoeve, P.

    2014-07-01

    We report on the present and future detector development activities for the European Space Agency Science Programme. The development of European technology in that field is a key mission enabler for the program, which requires TRL6 (ISO scale) by end of the definition phase, so called "mission adoption". This is particularly true for Astronomy and fundamental physics type missions. Current activities are in particular targeting large format and p-channel CCD, NIR and MWIR, LWIR wavelength ranges as well as related ASIC controller. For the longer term future mission plan (so called M4, M5 and L2 missions, M3 being PLATO and L1 JUICE), the extreme ends of the spectrum will be addressed. An overview of the detector status for the Earth Observation program is given in appendix, as most of the technologies are directly applicable to some extent to science missions, in particular for Planetary missions. The specific validation activities in place in the future mission preparation office in support to the space science program will be eventually briefly detailed.

  13. Mauritia flexuosa Presents In Vitro and In Vivo Antiplatelet and Antithrombotic Activities.

    PubMed

    Fuentes, Eduardo; Rodríguez-Pérez, Wilson; Guzmán, Luis; Alarcón, Marcelo; Navarrete, Simón; Forero-Doria, Oscar; Palomo, Iván

    2013-01-01

    Fruit from the palm Mauritia flexuosa is one of the most important species in Peru, Venezuela, Brazil, Colombia, Bolivia, and Guyana. The present study aimed to investigate the antiplatelet and antithrombotic activities of oil extracted from Mauritia flexuosa. The fatty acid contents were determined by gas chromatography-mass spectrometry. Oil extract of peel of Mauritia flexuosa was extracted by soxhlet extraction. The oil extract inhibited platelet secretion and aggregation induced by ADP, collagen, and TRAP-6 by a concentration-dependent way (0.1 to 1 mg/mL) without the participation of the adenylyl cyclase pathway and diminished platelet rolling and firm adhesion under flow conditions. Furthermore, the oil extract induced a marked increase in the rolling speed of leukocytes retained on the platelet surface, reflecting a reduction of rolling and less adhesion. At the concentrations used, the oil extract significantly decreased platelet release of sP-selectin, an atherosclerotic-related inflammatory mediator. Oil extract inhibited thrombus growth at the same concentration as that of aspirin, a classical reference drug. Finally, the data presented herein also demonstrate for the first time to our knowledge the protective effect of oil extracted from Mauritia flexuosa on platelet activation and thrombosis formation. PMID:24454503

  14. Carbohydrate-functionalized nanovaccines preserve HIV-1 antigen stability and activate antigen presenting cells

    PubMed Central

    Vela Ramirez, J.E.; Roychoudhury, R.; Habte, H.H.; Cho, M. W.; Pohl, N. L. B.; Narasimhan, B.

    2015-01-01

    The functionalization of polymeric nanoparticles with ligands that target specific receptors on immune cells offers the opportunity to tailor adjuvant properties by conferring pathogen mimicking attributes to the particles. Polyanhydride nanoparticles are promising vaccine adjuvants with desirable characteristics such as immunomodulation, sustained antigen release, activation of antigen presenting cells, and stabilization of protein antigens. These capabilities can be exploited to design nanovaccines against viral pathogens, such as HIV-1, due to the important role of dendritic cells and macrophages in viral spread. In this work, an optimized process was developed for carbohydrate functionalization of HIV-1 antigen-loaded polyanhydride nanoparticles. The carbohydrate-functionalized nanoparticles preserved antigenic properties upon release and also enabled sustained antigen release kinetics. Particle internalization was observed to be chemistry-dependent with positively charged nanoparticles being taken up more efficiently by dendritic cells. Up-regulation of the activation makers CD40 and CD206 was demonstrated with carboxymethyl-α-d-mannopyranosyl-(1,2)-d-mannopyranoside functionalized nanoparticles. The secretion of the cytokines IL-6 and TNF-α was shown to be chemistry-dependent upon stimulation with carbohydrate-functionalized nanoparticles. These results offer important new insights upon the interactions between carbohydrate-functionalized nanoparticles and antigen presenting cells and provide foundational information for the rational design of targeted nanovaccines against HIV-1. PMID:25068589

  15. Mauritia flexuosa Presents In Vitro and In Vivo Antiplatelet and Antithrombotic Activities

    PubMed Central

    Fuentes, Eduardo; Rodríguez-Pérez, Wilson; Guzmán, Luis; Alarcón, Marcelo; Navarrete, Simón; Forero-Doria, Oscar; Palomo, Iván

    2013-01-01

    Fruit from the palm Mauritia flexuosa is one of the most important species in Peru, Venezuela, Brazil, Colombia, Bolivia, and Guyana. The present study aimed to investigate the antiplatelet and antithrombotic activities of oil extracted from Mauritia flexuosa. The fatty acid contents were determined by gas chromatography—mass spectrometry. Oil extract of peel of Mauritia flexuosa was extracted by soxhlet extraction. The oil extract inhibited platelet secretion and aggregation induced by ADP, collagen, and TRAP-6 by a concentration-dependent way (0.1 to 1 mg/mL) without the participation of the adenylyl cyclase pathway and diminished platelet rolling and firm adhesion under flow conditions. Furthermore, the oil extract induced a marked increase in the rolling speed of leukocytes retained on the platelet surface, reflecting a reduction of rolling and less adhesion. At the concentrations used, the oil extract significantly decreased platelet release of sP-selectin, an atherosclerotic-related inflammatory mediator. Oil extract inhibited thrombus growth at the same concentration as that of aspirin, a classical reference drug. Finally, the data presented herein also demonstrate for the first time to our knowledge the protective effect of oil extracted from Mauritia flexuosa on platelet activation and thrombosis formation. PMID:24454503

  16. Availability of surface boron species in improved oxygen reduction activity of Pt catalysts: A first-principles study

    NASA Astrophysics Data System (ADS)

    Zhang, Libo; Zhou, Gang

    2016-04-01

    The oxidation process of boron (B) species on the Pt(111) surface and the beneficial effects of boron oxides on the oxygen reduction activity are investigated by first-principles calculations. The single-atom B anchored on the Pt surface has a great attraction for the oxygen species in the immediate environment. With the dissociation of molecular oxygen, a series of boron oxides is formed in succession, both indicating exothermic oxidation reactions. After BO2 is formed, the subsequent O atom immediately participates in the oxygen reduction reaction. The calculated O adsorption energy is appreciably decreased as compared to Pt catalysts, and more approximate to the optimal value of the volcano plot, from which is clear that O hydrogenation kinetics is improved. The modulation mechanism is mainly based on the electron-deficient nature of stable boron oxides, which normally reduces available electronic states of surface Pt atoms that bind the O by facilitating more electron transfer. This modification strategy from the exterior opens the new way, different from the alloying, to efficient electrocatalyst design for PEMFCs.

  17. Availability of surface boron species in improved oxygen reduction activity of Pt catalysts: A first-principles study.

    PubMed

    Zhang, Libo; Zhou, Gang

    2016-04-14

    The oxidation process of boron (B) species on the Pt(111) surface and the beneficial effects of boron oxides on the oxygen reduction activity are investigated by first-principles calculations. The single-atom B anchored on the Pt surface has a great attraction for the oxygen species in the immediate environment. With the dissociation of molecular oxygen, a series of boron oxides is formed in succession, both indicating exothermic oxidation reactions. After BO2 is formed, the subsequent O atom immediately participates in the oxygen reduction reaction. The calculated O adsorption energy is appreciably decreased as compared to Pt catalysts, and more approximate to the optimal value of the volcano plot, from which is clear that O hydrogenation kinetics is improved. The modulation mechanism is mainly based on the electron-deficient nature of stable boron oxides, which normally reduces available electronic states of surface Pt atoms that bind the O by facilitating more electron transfer. This modification strategy from the exterior opens the new way, different from the alloying, to efficient electrocatalyst design for PEMFCs. PMID:27083744

  18. The effect of the active principle of Solanum malacoxylon on rabbits and the inhibition of its action by actinomycin D.

    PubMed

    Basudde, C D; Humphreys, D J

    1975-07-25

    The oral administration of an aqueous extract of 2.5 g of the dried leaves of Solanum malacoxylon (DLSM) produced a rapid hyperphosphataemia, which becomes apparent 4 to 8 h after treatment, in the rabbit. This effect was not accompanied by any significant change in plasma calcium, mangesium, total protein, albumin, urea and creatinine concentration. The urinary excretion of calcium, magnesium, and inorganic phosphate was markedly increased 24 and 48 h after treatment with the extract and was not accompanied by any significant change in the urinary excretion of hydroxyproline. The hyperphosphataemic effect of the DLSM extract was inhibited by Actinomycin D. It appeared that DLSM does not cause bone resorption in normal rabbits maintained on a diet containing adequate levels of calcium and phosphorus. The increased urinary excretion of calcium magnesium and inorganic phosphate after treatment with DLSM extract appeared to be due to increased intestinal absorption. The absence of any significant change in plasma urea and creatinine concentration after treatment with DLSM extract, and the inhibition of the hyperphosphataemic effect by Actinomycin D, indicated that this was a characteristic response of the rabbit to the active principle, and that it was not due to renal damage. The inhibition of the hyperphosphataemic effect of DLSM by Actinomyein D showed that its action involves the transcription of DNA to RNA and protein synthesis. PMID:1148896

  19. The proteasome activator 11 S REG (PA28) and class I antigen presentation.

    PubMed Central

    Rechsteiner, M; Realini, C; Ustrell, V

    2000-01-01

    There are two immune responses in vertebrates: humoral immunity is mediated by circulating antibodies, whereas cytotoxic T lymphocytes (CTL) confer cellular immunity. CTL lyse infected cells upon recognition of cell-surface MHC Class I molecules complexed with foreign peptides. The displayed peptides are produced in the cytosol by degradation of host proteins or proteins from intracellular pathogens that might be present. Proteasomes are cylindrical multisubunit proteases that generate many of the peptides eventually transferred to the cell surface for immune surveillance. In mammalian proteasomes, six active sites face a central chamber. As this chamber is sealed off from the enzyme's surface, there must be mechanisms to promote entry of substrates. Two protein complexes have been found to bind the ends of the proteasome and activate it. One of the activators is the 19 S regulatory complex of the 26 S proteasome; the other activator is '11 S REG' [Dubiel, Pratt, Ferrell and Rechsteiner (1992) J. Biol. Chem. 267, 22369-22377] or 'PA28' [Ma, Slaughter and DeMartino (1992) J. Biol. Chem. 267, 10515-10523]. During the past 7 years, our understanding of the structure of REG molecules has increased significantly, but much less is known about their biological functions. There are three REG subunits, namely alpha, beta and gamma. Recombinant REGalpha forms a ring-shaped heptamer of known crystal structure. 11 S REG is a heteroheptamer of alpha and beta subunits. REGgamma is also presumably a heptameric ring, and it is found in the nuclei of the nematode work Caenorhabditis elegans and higher organisms, where it may couple proteasomes to other nuclear components. REGalpha and REGbeta, which are abundant in vertebrate immune tissues, are located mostly in the cytoplasm. Synthesis of REG alpha and beta subunits is induced by interferon-gamma, and this has led to the prevalent hypothesis that REG alpha/beta hetero-oligomers play an important role in Class I antigen

  20. Multivariable Observations of Pre and Co-Seismic Electromagnetic Activity in Peru: Past, Present and Future

    NASA Astrophysics Data System (ADS)

    Heraud, J. A.; Lira, J. A.; Montes, L.; Rosas, S.; Centa, V.; Bleier, T. E.

    2012-12-01

    The Mw8.0 earthquake in Pisco, Peru of August 15, 2007 was reported previously and shown to have produced extensive co-seismic luminescence away from the epicenter. Continued research will be presented in which a high coincidence exists between the location of the areas where the luminescence was video recorded and reported by qualified witnesses and the geological formation in the bay in which Jurassic and Cretaceous lithologic igneous components are present, a condition that contributes to the displacement of electric charges in the rock. Additionally, the San Lorenzo Island has become the focus of a new research effort due to the past record of pre-seismic EQLs reported and published in relation with the mega-earthquake of 1746, the previously reported co-seismic EQLs in 2007 and new evidence of pre-seismic EQLs reported one and a half days before a ML4.6 earthquake on July 29, 2012. New experiments are hitherto being deployed in San Lorenzo Island to pursue the identification of favorable conditions for the propagation of electric charges in connection with pressure on rocks due to seismic activity. Thus, continuously recording video cameras, charge potential measuring plates, recording of HF and VHF noise and the installation of a new magnetometer to detect pulse activity in the local magnetic field and twin (+/-) air conductivity sensors are being installed on the island. Additionally, a new rock experiment to analyze the displacement of charges with local rocks is under way. The expectation of a Mega earthquake in the Lima area is building up as we approach the third century without mayor seismic activity in the area so the deployment of a new network of five magnetometers for the Lima area has started.

  1. [The present crisis of the publication activity in anesthesia research in Japan and its countermeasure].

    PubMed

    Hirota, Kazuyoshi

    2015-01-01

    In Japan, a reduction in the number of qualified anesthesiologists has become apparent particularly in local university hospitals since the introduction of a new postgraduate clinical training system in 2004. In addition, our younger generation seems to desire the qualification as an anesthesiologists but not the research degree of Doctor of Medicine. As a consequence of high clinical workload and a relative lack of interest in research degrees, the publication of anesthesia research papers from Japan is progressively declining. In addition, the issue of data fabrication in randomized controlled clinical trials by Fujii had a negative impact on the motivation within our specialty to perform research and may consequently decrease research publications in Japan. If we do not engage in anesthesia research activities, it is really possible that our colleagues and patients may view us simply as technicians in near future. In the extreme case a medical degree may no longer be required for anesthesiologists. However, once we were in that kind of position and situation the restoration would be difficult. To take countermeasure against this decline in anesthesia research activity, I would like to present proposals as follows. Japanese Society of Anesthesiologists (JSA) and each educational institution should desperately emdeavour to encourage anesthesiologists to enter graduate school of medicine, develop environment for continuation in employment of female anesthetists during pregnancy and parenting and to perform planning and implementation of JSA initiated research projects educating young anesthesiologist for English article writing and medical ethics. Moreover, each anesthesiologist must deeply recognize the present crisis of anesthesia research activity in Japan, and then do what should be done now. PMID:25868199

  2. Xenohormetic and anti-aging activity of secoiridoid polyphenols present in extra virgin olive oil

    PubMed Central

    Menendez, Javier A.; Joven, Jorge; Aragonès, Gerard; Barrajón-Catalán, Enrique; Beltrán-Debón, Raúl; Borrás-Linares, Isabel; Camps, Jordi; Corominas-Faja, Bruna; Cufí, Sílvia; Fernández-Arroyo, Salvador; Garcia-Heredia, Anabel; Hernández-Aguilera, Anna; Herranz-López, María; Jiménez-Sánchez, Cecilia; López-Bonet, Eugeni; Lozano-Sánchez, Jesús; Luciano-Mateo, Fedra; Martin-Castillo, Begoña; Martin-Paredero, Vicente; Pérez-Sánchez, Almudena; Oliveras-Ferraros, Cristina; Riera-Borrull, Marta; Rodríguez-Gallego, Esther; Quirantes-Piné, Rosa; Rull, Anna; Tomás-Menor, Laura; Vazquez-Martin, Alejandro; Alonso-Villaverde, Carlos; Micol, Vicente; Segura-Carretero, Antonio

    2013-01-01

    Aging can be viewed as a quasi-programmed phenomenon driven by the overactivation of the nutrient-sensing mTOR gerogene. mTOR-driven aging can be triggered or accelerated by a decline or loss of responsiveness to activation of the energy-sensing protein AMPK, a critical gerosuppressor of mTOR. The occurrence of age-related diseases, therefore, reflects the synergistic interaction between our evolutionary path to sedentarism, which chronically increases a number of mTOR activating gero-promoters (e.g., food, growth factors, cytokines and insulin) and the “defective design” of central metabolic integrators such as mTOR and AMPK. Our laboratories at the Bioactive Food Component Platform in Spain have initiated a systematic approach to molecularly elucidate and clinically explore whether the “xenohormesis hypothesis,” which states that stress-induced synthesis of plant polyphenols and many other phytochemicals provides an environmental chemical signature that upregulates stress-resistance pathways in plant consumers, can be explained in terms of the reactivity of the AMPK/mTOR-axis to so-called xenohormetins. Here, we explore the AMPK/mTOR-xenohormetic nature of complex polyphenols naturally present in extra virgin olive oil (EVOO), a pivotal component of the Mediterranean style diet that has been repeatedly associated with a reduction in age-related morbid conditions and longer life expectancy. Using crude EVOO phenolic extracts highly enriched in the secoiridoids oleuropein aglycon and decarboxymethyl oleuropein aglycon, we show for the first time that (1) the anticancer activity of EVOO secoiridoids is related to the activation of anti-aging/cellular stress-like gene signatures, including endoplasmic reticulum (ER) stress and the unfolded protein response, spermidine and polyamine metabolism, sirtuin-1 (SIRT1) and NRF2 signaling; (2) EVOO secoiridoids activate AMPK and suppress crucial genes involved in the Warburg effect and the self-renewal capacity of

  3. The modality-switch effect: visually and aurally presented prime sentences activate our senses

    PubMed Central

    Scerrati, Elisa; Baroni, Giulia; Borghi, Anna M.; Galatolo, Renata; Lugli, Luisa; Nicoletti, Roberto

    2015-01-01

    Verifying different sensory modality properties for concepts results in a processing cost known as the modality-switch effect. It has been argued that this cognitive cost is the result of a perceptual simulation. This paper extends this argument and reports an experiment investigating whether the effect is the result of an activation of sensory information which can also be triggered by perceptual linguistically described stimuli. Participants were first exposed to a prime sentence describing a light or a sound’s perceptual property (e.g., “The light is flickering”, “The sound is echoing”), then required to perform a property-verification task on a target sentence (e.g., “Butter is yellowish”, “Leaves rustle”). The content modalities of the prime and target sentences could be compatible (i.e., in the same modality: e.g., visual–visual) or not (i.e., in different modalities). Crucially, we manipulated the stimuli’s presentation modality such that half of the participants was faced with written sentences while the other half was faced with aurally presented sentences. Results show a cost when two different modalities alternate, compared to when the same modality is repeated with both visual and aural stimuli presentations. This result supports the embodied and grounded cognition view which claims that conceptual knowledge is grounded into the perceptual system. Specifically, this evidence suggests that sensory modalities can be pre-activated through the simulation of either read or listened linguistic stimuli describing visual or acoustic perceptual properties. PMID:26579049

  4. Dynamic sealing principles

    NASA Technical Reports Server (NTRS)

    Zuk, J.

    1976-01-01

    The fundamental principles governing dynamic sealing operation are discussed. Different seals are described in terms of these principles. Despite the large variety of detailed construction, there appear to be some basic principles, or combinations of basic principles, by which all seals function, these are presented and discussed. Theoretical and practical considerations in the application of these principles are discussed. Advantages, disadvantages, limitations, and application examples of various conventional and special seals are presented. Fundamental equations governing liquid and gas flows in thin film seals, which enable leakage calculations to be made, are also presented. Concept of flow functions, application of Reynolds lubrication equation, and nonlubrication equation flow, friction and wear; and seal lubrication regimes are explained.

  5. Buridan's Principle

    NASA Astrophysics Data System (ADS)

    Lamport, Leslie

    2012-08-01

    Buridan's principle asserts that a discrete decision based upon input having a continuous range of values cannot be made within a bounded length of time. It appears to be a fundamental law of nature. Engineers aware of it can design devices so they have an infinitessimal probability of not making a decision quickly enough. Ignorance of the principle could have serious consequences.

  6. Disaster planning: the past, present, and future concepts and principles of managing a surge of burn injured patients for those involved in hospital facility planning and preparedness.

    PubMed

    Kearns, Randy D; Holmes, James H; Alson, Roy L; Cairns, Bruce A

    2014-01-01

    The 9/11 attacks reframed the narrative regarding disaster medicine. Bypass strategies have been replaced with absorption strategies and are more specifically described as "surge capacity." In the succeeding years, a consensus has coalesced around stratifying the surge capacity into three distinct tiers: conventional, contingency, and crisis surge capacities. For the purpose of this work, these three distinct tiers were adapted specifically to burn surge for disaster planning activities at hospitals where burn centers are not located. A review was conducted involving published plans, other related academic works, and findings from actual disasters as well as modeling. The aim was to create burn-specific definitions for surge capacity for hospitals where a burn center is not located. The three-tier consensus description of surge capacity is delineated in their respective stratifications by what will hereinafter be referred to as the three "S's"; staff, space, and supplies (also referred to as supplies, pharmaceuticals, and equipment). This effort also included the creation of a checklist for nonburn center hospitals to assist in their development of a burn surge plan. Patients with serious burn injuries should always be moved to and managed at burn centers, but during a medical disaster with significant numbers of burn injured patients, there may be impediments to meeting this goal. It may be necessary for burn injured patients to remain for hours in an outlying hospital until being moved to a burn center. This work was aimed at aiding local and regional hospitals in developing an extemporizing measure until their burn injured patients can be moved to and managed at a burn center(s). PMID:23817001

  7. Widely available active sites on Ni2P for electrochemical hydrogen evolution--insights from first principles calculations.

    PubMed

    Hansen, Martin H; Stern, Lucas-Alexandre; Feng, Ligang; Rossmeisl, Jan; Hu, Xile

    2015-04-28

    We present insights into the mechanism and the active site for hydrogen evolution on nickel phosphide (Ni2P). Ni2P was recently discovered to be a very active non-precious hydrogen evolution catalyst. Current literature attributes the activity of Ni2P to a particular site on the (0001) facet. In the present study, using Density Functional Theory (DFT) calculations, we show that several widely available low index crystal facets on Ni2P have better properties for a high catalytic activity. DFT calculations were used to identify moderately bonding nickel bridge sites and nickel hollow sites for hydrogen adsorption and to calculate barriers for the Tafel pathway. The investigated surfaces in this study were the (101̅0), (1̅1̅20), (112̅0), (112̅1) and (0001) facets of the hexagonal Ni2P crystal. In addition to the DFT results, we present experiments on Ni2P nanowires growing along the 〈0001〉 direction, which are shown as efficient hydrogen evolution catalysts. The experimental results add these nanowires to a variety of different morphologies of Ni2P, which are all active for HER. PMID:25812670

  8. The Principles of Leadership.

    ERIC Educational Resources Information Center

    Burns, Gerald P.

    The primary but not exclusive concern in this monograph is the principles and qualities of dynamic leaders of people rather than of ideas or cultural and artistic pursuits. Theories of leadership in the past, present, and future are discussed, as are the principles, rewards, exercise, and philosophy of leadership. A bibliography is included. (MSE)

  9. Effective Presentation of Metabolic Rate Information for Lunar Extravehicular Activity (EVA)

    NASA Technical Reports Server (NTRS)

    Mackin, Michael A.; Gonia, Philip; Lombay-Gonzalez, Jose

    2010-01-01

    During human exploration of the lunar surface, a suited crewmember needs effective and accurate information about consumable levels remaining in their life support system. The information must be presented in a manner that supports real-time consumable monitoring and route planning. Since consumable usage is closely tied to metabolic rate, the lunar suit must estimate metabolic rate from life support sensors, such as oxygen tank pressures, carbon dioxide partial pressure, and cooling water inlet and outlet temperatures. To provide adequate warnings that account for traverse time for a crewmember to return to a safe haven, accurate forecasts of consumable depletion rates are required. The forecasts must be presented to the crewmember in a straightforward, effective manner. In order to evaluate methods for displaying consumable forecasts, a desktop-based simulation of a lunar Extravehicular Activity (EVA) has been developed for the Constellation lunar suite s life-support system. The program was used to compare the effectiveness of several different data presentation methods.

  10. The Principles of Phototransferred Thermoluminescence

    SciTech Connect

    Moscovitch, Marko

    2011-05-05

    The principles of phototransferred thermoluminescence (PTTL) are described, and some of the basic theoretical ideas underlying this technique are presented. It is demonstrated that the PTTL efficiency is dependent on the photon energy as well as on the activation energies of the various traps involved in the process. A simple two-traps-one-recombination-center model is capable of predicting a variety of different PTTL behaviors, some already were observed experimentally.

  11. Energy principles in architectural design

    SciTech Connect

    Dean, E.

    1981-01-01

    A foundation of basic information pertaining to design and energy use in buildings is presented with emphasis on principles and concepts rather than applications of particular solution. Energy impacts of landforms and topography, vegetation, wind and ventilation, and sun on planning and designing the site are discused. General design considerations involving passive heating, cooling, and lighting systems are detailed. For the design of active building systems, heating, cooling, lighting, and HVAC systems are described. (MCW)

  12. Vaccine activation of the nutrient sensor GCN2 in dendritic cells enhances antigen presentation.

    PubMed

    Ravindran, Rajesh; Khan, Nooruddin; Nakaya, Helder I; Li, Shuzhao; Loebbermann, Jens; Maddur, Mohan S; Park, Youngja; Jones, Dean P; Chappert, Pascal; Davoust, Jean; Weiss, David S; Virgin, Herbert W; Ron, David; Pulendran, Bali

    2014-01-17

    The yellow fever vaccine YF-17D is one of the most successful vaccines ever developed in humans. Despite its efficacy and widespread use in more than 600 million people, the mechanisms by which it stimulates protective immunity remain poorly understood. Recent studies using systems biology approaches in humans have revealed that YF-17D-induced early expression of general control nonderepressible 2 kinase (GCN2) in the blood strongly correlates with the magnitude of the later CD8(+) T cell response. We demonstrate a key role for virus-induced GCN2 activation in programming dendritic cells to initiate autophagy and enhanced antigen presentation to both CD4(+) and CD8(+) T cells. These results reveal an unappreciated link between virus-induced integrated stress response in dendritic cells and the adaptive immune response. PMID:24310610

  13. Active Target detectors for studies with exotic beams: Present and next future

    NASA Astrophysics Data System (ADS)

    Mittig, W.; Beceiro-Novo, S.; Fritsch, A.; Abu-Nimeh, F.; Bazin, D.; Ahn, T.; Lynch, W. G.; Montes, F.; Shore, A.; Suzuki, D.; Usher, N.; Yurkon, J.; Kolata, J. J.; Howard, A.; Roberts, A. L.; Tang, X. D.; Becchetti, F. D.

    2015-06-01

    Reaccelerated radioactive beams near the Coulomb barrier, which are starting to be available from the ReA3 accelerator at NSCL and in next future at FRIB, will open up new opportunities for the study of nuclear structure near the drip lines. Efficient measurement techniques must be developed to compensate for the limited intensity of the most exotic beams. The Active-Target Time Projection Chamber (AT-TPC) constructed at MSU solves this problem by providing the increased luminosity of a thick target while maintaining a good energy resolution by tracking the reaction vertex over an essentially 4 π solid angle. The AT-TPC and similar detectors allow us to take full advantage of the radioactive ion beams at present and future nuclear physics facilities to explore the frontier of rare isotopes.

  14. Fighting the stigma caused by mental disorders: past perspectives, present activities, and future directions

    PubMed Central

    STUART, HEATHER

    2008-01-01

    People who live with mental illnesses are among the most stigmatized groups in society. In 1996, in recognition of the particularly harsh burden caused by the stigma associated with schizophrenia, the WPA initiated a global anti-stigma program, Open-the-Doors. In 2005, a WPA Section on Stigma and Mental Health was created, with a broader mandate to reduce stigma and discrimination caused by mental disabilities in general. In light of these impor-tant developments, and the growing public health interest in stigma reduction, this paper reflects on the past perspectives that have led us to our current position, reviews present activities and accomplishments, and identifies challenges that the Section members will face in their future efforts to reduce the stigma caused by mental disorders. PMID:18836546

  15. 21st Century Extravehicular Activities: Synergizing Past and Present Training Methods for Future Spacewalking Success

    NASA Technical Reports Server (NTRS)

    Moore, Sandra K.; Gast, Matthew A.

    2009-01-01

    Neil Armstrong's understated words, "That's one small step for man, one giant leap for mankind." were spoken from Tranquility Base forty years ago. Even today, those words resonate in the ears of millions, including many who had yet to be born when man first landed on the surface of the moon. By their very nature, and in the the spirit of exploration, extravehicular activities (EVAs) have generated much excitement throughout the history of manned spaceflight. From Ed White's first space walk in June of 1965, to the first steps on the moon in 1969, to the expected completion of the International Space Station (ISS), the ability to exist, live and work in the vacuum of space has stood as a beacon of what is possible. It was NASA's first spacewalk that taught engineers on the ground the valuable lesson that successful spacewalking requires a unique set of learned skills. That lesson sparked extensive efforts to develop and define the training requirements necessary to ensure success. As focus shifted from orbital activities to lunar surface activities, the required skill-set and subsequently the training methods, changed. The requirements duly changed again when NASA left the moon for the last time in 1972 and have continued to evolve through the Skylab, Space Shuttle; and ISS eras. Yet because the visits to the moon were so long ago, NASA's expertise in the realm of extra-terrestrial EVAs has diminished. As manned spaceflight again shifts its focus beyond low earth orbit, EVA success will depend on the ability to synergize the knowledge gained over 40+ years of spacewalking to create a training method that allows a single crewmember to perform equally well, whether performing an EVA on the surface of the Moon, while in the vacuum of space, or heading for a rendezvous with Mars. This paper reviews NASA's past and present EVA training methods and extrapolates techniques from both to construct the basis for future EVA astronaut training.

  16. 21st Century extravehicular activities: Synergizing past and present training methods for future spacewalking success

    NASA Astrophysics Data System (ADS)

    Moore, Sandra K.; Gast, Matthew A.

    2010-10-01

    Neil Armstrong's understated words, "That's one small step for man, one giant leap for mankind" were spoken from Tranquility Base forty years ago. Even today, those words resonate in the ears of millions, including many who had yet to be born when man first landed on the surface of the moon. By their very nature, and in the true spirit of exploration, extravehicular activities (EVAs) have generated much excitement throughout the history of manned spaceflight. From Ed White's first spacewalk in the June of 1965, to the first steps on the moon in 1969, to the expected completion of the International Space Station (ISS), the ability to exist, live and work in the vacuum of space has stood as a beacon of what is possible. It was NASA's first spacewalk that taught engineers on the ground the valuable lesson that successful spacewalking requires a unique set of learned skills. That lesson sparked extensive efforts to develop and define the training requirements necessary to ensure success. As focus shifted from orbital activities to lunar surface activities, the required skill set and subsequently the training methods changed. The requirements duly changed again when NASA left the moon for the last time in 1972 and have continued to evolve through the SkyLab, Space Shuttle, and ISS eras. Yet because the visits to the moon were so long ago, NASA's expertise in the realm of extra-terrestrial EVAs has diminished. As manned spaceflight again shifts its focus beyond low earth orbit, EVA's success will depend on the ability to synergize the knowledge gained over 40+ years of spacewalking to create a training method that allows a single crewmember to perform equally well, whether performing an EVA on the surface of the Moon, while in the vacuum of space, or heading for a rendezvous with Mars. This paper reviews NASA's past and present EVA training methods and extrapolates techniques from both to construct the basis for future EVA astronaut training.

  17. Spatiotemporally synchronized cancer combination therapy using photo-activated nanoparticle drug delivery systems (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hasan, Tayyaba

    2016-03-01

    This talk will introduce a new nanotechnology platform for cancer combination therapy that utilizes near infrared light activation not only for photodynamic damage but also as an extrinsic mechanism to initiate release of complimentary drugs to suppress dynamic bursts in molecular signaling networks that promote tumor cell survival and treatment escape. The goal is to achieve co-delivery with concomitant activity of photodynamic, molecular inhibitor and chemotherapeutic agents, selectively within the tumor. This approach overcomes challenges in achieving synergistic interactions using sequential drug delivery. Conventional drug delivery is compromised by the differential pharmacokinetics of individual agents and potentially antagonistic effects—such as vascular shutdown by one agent that limits delivery of the second. Here, photodynamic damage—which efficiently kills drug-resistant cells via damage of common proteins involved in drug-resistance (such as anti-apoptosis factors and drug-efflux transporters)—is synchronized spatially and temporally with the photo-initiated release of complimentary agents—to enable full interaction amongst the individual therapies. This spatiotemporal synchronization offers new prospects for exploiting time-sensitive synergistic interactions. Specific implementations of these concepts will be presented in preclinical models of cancer. Strategies to enable molecular-targeting of cancer cells via site-specific attachment of targeting moieties to the outer lipid shell of these nanovehicles will also be discussed. If successful in humans, this new paradigm for synchronized, tumor-focused combination therapy will ultimately supersede the present use of chronic drug injection by increasing efficacy per cycle whilst reducing systemic exposure to toxic drugs.

  18. Carbohydrate-functionalized nanovaccines preserve HIV-1 antigen stability and activate antigen presenting cells.

    PubMed

    Vela Ramirez, J E; Roychoudhury, R; Habte, H H; Cho, M W; Pohl, N L B; Narasimhan, B

    2014-01-01

    The functionalization of polymeric nanoparticles with ligands that target specific receptors on immune cells offers the opportunity to tailor adjuvant properties by conferring pathogen mimicking attributes to the particles. Polyanhydride nanoparticles are promising vaccine adjuvants with desirable characteristics such as immunomodulation, sustained antigen release, activation of antigen presenting cells (APCs), and stabilization of protein antigens. These capabilities can be exploited to design nanovaccines against viral pathogens, such as HIV-1, due to the important role of dendritic cells (DCs) and macrophages in viral spread. In this work, an optimized process was developed for carbohydrate functionalization of HIV-1 antigen-loaded polyanhydride nanoparticles. The carbohydrate-functionalized nanoparticles preserved antigenic properties upon release and also enabled sustained antigen release kinetics. Particle internalization was observed to be chemistry-dependent with positively charged nanoparticles being taken up more efficiently by DCs. Up-regulation of the activation makers CD40 and CD206 was demonstrated with carboxymethyl-α-d-mannopyranosyl-(1,2)-d-mannopyranoside functionalized nanoparticles. The secretion of the cytokines IL-6 and TNF-α was shown to be chemistry-dependent upon stimulation with carbohydrate-functionalized nanoparticles. These results offer important new insights upon the interactions between carbohydrate-functionalized nanoparticles and APCs and provide foundational information for the rational design of targeted nanovaccines against HIV-1. PMID:25068589

  19. A summary of present-day gully formation and activity on Mars

    NASA Astrophysics Data System (ADS)

    Diniega, Serina; Hansen, Candice; McEwen, Alfred; Dundas, Colin; Byrne, Shane

    2016-07-01

    trends and variations in gully size, morphology, orientation, and location are additionally examined as indications of a seasonal (or other) control, as well as variations with latitude, dune type/size/orientation, or Mars year. This presentation will summarize the results of our monitoring campaigns, and will compare the data that are available about gullies of different morphologies and locations. Our aim is to identify possible similarities (and differences) in gully activity processes across Mars, and to estimate the rates of gully formation and modification processes (as has been done for gullies in the southern mid-latitudes [3]). Such estimates would aid interpretation of the likely ages of observed gullies, which have implications for whether records of past (and potential aqueous) gully formation processes are still observable. [1] Diniega et al. (2010) Geology, 38, 1047-1050. [2] Dundas et al. (2012) Icarus, 220, 124-143. [3] Dundas et al. (2015) Icarus, 251, 244-263. [4] Dundas et al. (2010) GRL, 37, L07202. [5] Vincendon (2015) JGR, 120, 1859-1879. [6] Harrison et al. (2015) Icarus, 252, 236-254. [7] Pilorget & Forget (2016) Nature Geosci. 9, 65-69. [8] Vincendon et al. (2010) JGR, 115, E10001. [9] Horgan & Bell (2012) Geophys. Res. Lett. 39, L09201. [10] Hansen et al., (2011) Science 331, 575-578. [11] Hansen et al. (2015) Icarus 251, 264-267.

  20. Selective monoamine oxidase B inhibition by an Aphanizomenon flos-aquae extract and by its constitutive active principles phycocyanin and mycosporine-like amino acids.

    PubMed

    Scoglio, Stefano; Benedetti, Yanina; Benvenuti, Francesca; Battistelli, Serafina; Canestrari, Franco; Benedetti, Serena

    2014-06-15

    Aphanizomenon flos-aquae (AFA) is a fresh water unicellular blue-green alga that has been traditionally used for over 25 years for its health-enhancing properties. Recent studies have shown the ability of a proprietary AFA extract (Klamin(®)) to improve mood, counteract anxiety, and enhance attention and learning. Aim of this study was to test the monoamine oxidase (MAO) inhibition activity of the same AFA extract and of its constituents phycocyanin (AFA-PC) and mycosporine-like aminoacids (AFA-MAAs). All compounds showed a dose-dependent selective inhibition of MAO-B activity as compared to MAO-A. The IC50 values of the AFA extract (concentration 10 mg/ml), AFA-PC and AFA-MAAs were 6.4 μl/ml, 1.33 μM and 1.98 μM, respectively, evidencing a mixed-type of inhibition for the AFA extract (Ki 0.99 μl/ml), a non-competitive inhibition for AFA-PC (Ki 1.06 μM) and a competitive inhibition for AFA-MAAs (Ki 0.585 μM). These results are important to explain the neuromodulating properties of the AFA extract Klamin(®), which is rich in phenylethylamine, a general neuromodulator, that would nevertheless rapidly destroyed by MAO-B enzymes without the inhibitory activity of the synergic active principles AFA-PC and AFA-MAAs. The present investigation thus proposes the extract as potentially relevant in clinical areas such as mood disorders and neurodegenerative diseases. PMID:24690316

  1. A novel synthetic quinolinone inhibitor presents proteolytic and hemorrhagic inhibitory activities against snake venom metalloproteases.

    PubMed

    Baraldi, Patrícia T; Magro, Angelo J; Matioli, Fábio F; Marcussi, Silvana; Lemke, Ney; Calderon, Leonardo A; Stábeli, Rodrigo G; Soares, Andreimar M; Correa, Arlene G; Fontes, Marcos R M

    2016-02-01

    Metalloproteases play a fundamental role in snake venom envenomation inducing hemorrhagic, fibrigen(ogen)olytic and myotoxic effects in their victims. Several snake venoms, such as those from the Bothrops genus, present important local effects which are not efficiently neutralized by conventional serum therapy. Consequently, these accidents may result in permanent sequelae and disability, creating economic and social problems, especially in developing countries, leading the attention of the World Health Organization that considered ophidic envenomations a neglected tropical disease. Aiming to produce an efficient inhibitor against bothropic venoms, we synthesized different molecules classified as quinolinones - a group of low-toxic chemical compounds widely used as antibacterial and antimycobacterial drugs - and tested their inhibitory properties against hemorrhage caused by bothropic venoms. The results from this initial screening indicated the molecule 2-hydroxymethyl-6-methoxy-1,4-dihydro-4-quinolinone (Q8) was the most effective antihemorrhagic compound among all of the assayed synthetic quinolinones. Other in vitro and in vivo experiments showed this novel compound was able to inhibit significantly the hemorrhagic and/or proteolytic activities of bothropic crude venoms and isolated snake venom metalloproteases (SVMPs) even at lower concentrations. Docking and molecular dynamic simulations were also performed to get insights into the structural basis of Q8 inhibitory mechanism against proteolytic and hemorrhagic SVMPs. These structural studies demonstrated that Q8 may form a stable complex with SVMPs, impairing the access of substrates to the active sites of these toxins. Therefore, both experimental and structural data indicate that Q8 compound is an interesting candidate for antiophidic therapy, particularly for the treatment of the hemorrhagic and necrotic effects induced by bothropic venoms. PMID:26700145

  2. Three Activities To Assist Biology Teachers in Presenting Conceptually Difficult Topics.

    ERIC Educational Resources Information Center

    Taylor, Neil; Tulip, David

    1997-01-01

    Outlines three activities for different areas of biology that can serve as motivators for students or as demonstrations. Each activity is easy to organize and uses available materials. Topics include evolution, anaerobic respiration, and heat loss. (DDR)

  3. Healthy Kids Out of School: Using Mixed Methods to Develop Principles for Promoting Healthy Eating and Physical Activity in Out-of-School Settings in the United States

    PubMed Central

    Sharma, Shanti; Dietz, William H.; Dolan, Peter R.; Nelson, Miriam E.; Newman, Molly B.; Rockeymoore, Maya; Economos, Christina D.

    2014-01-01

    Introduction Widespread practices supporting availability of healthful foods, beverages, and physical activity in out-of-school-time (OST) settings would further obesity prevention efforts. The objective of this article was to describe principles to guide policy development in support of healthy eating and physical activity practices in out-of-school settings to promote obesity prevention. Methods The Institute of Medicine’s L.E.A.D. framework (Locate Evidence, Evaluate it, Assemble it, and Inform Decisions) was used to identify practices relevant to children’s healthful eating in most OST settings: 1) locate and evaluate information from a national survey of children’s perceptions of healthful-food access; published research, reports, policies and guidelines; and roundtables with OST organizations’ administrators; 2) assemble information to prioritize actionable practices; and 3) inform programmatic direction. Results Three evidence-informed guiding principles for short-duration OST resulted: 1) drink right: choose water instead of sugar-sweetened beverages; 2) move more: boost movement and physical activity in all programs; and 3) snack smart: fuel up on fruits and vegetables. Conclusion Healthy Kids Out of School was launched to support the dissemination and implementation of these guiding principles in short-duration OST settings, complementing efforts in other OST settings to shift norms around eating and physical activity. PMID:25551182

  4. Improved Neural Signal Classification in a Rapid Serial Visual Presentation Task Using Active Learning.

    PubMed

    Marathe, Amar R; Lawhern, Vernon J; Wu, Dongrui; Slayback, David; Lance, Brent J

    2016-03-01

    The application space for brain-computer interface (BCI) technologies is rapidly expanding with improvements in technology. However, most real-time BCIs require extensive individualized calibration prior to use, and systems often have to be recalibrated to account for changes in the neural signals due to a variety of factors including changes in human state, the surrounding environment, and task conditions. Novel approaches to reduce calibration time or effort will dramatically improve the usability of BCI systems. Active Learning (AL) is an iterative semi-supervised learning technique for learning in situations in which data may be abundant, but labels for the data are difficult or expensive to obtain. In this paper, we apply AL to a simulated BCI system for target identification using data from a rapid serial visual presentation (RSVP) paradigm to minimize the amount of training samples needed to initially calibrate a neural classifier. Our results show AL can produce similar overall classification accuracy with significantly less labeled data (in some cases less than 20%) when compared to alternative calibration approaches. In fact, AL classification performance matches performance of 10-fold cross-validation (CV) in over 70% of subjects when training with less than 50% of the data. To our knowledge, this is the first work to demonstrate the use of AL for offline electroencephalography (EEG) calibration in a simulated BCI paradigm. While AL itself is not often amenable for use in real-time systems, this work opens the door to alternative AL-like systems that are more amenable for BCI applications and thus enables future efforts for developing highly adaptive BCI systems. PMID:26600162

  5. Present-Day Seasonal Gully Activity in a South Polar Pit (Sisyphi Cavi) on Mars

    NASA Astrophysics Data System (ADS)

    Raack, Jan; Reiss, Dennis; Appéré, Thomas; Vincendon, Mathieu; Ruesch, Ottaviano; Hiesinger, Harald

    2014-05-01

    Seasonal activity of gullies under current climatic conditions on Mars was observed by [1-7]. Dundas et al. [2] reviewed the present-day activity of classical gullies (including the gully presented in this work), dune gullies, and other mass wasting processes in the southern hemisphere on Mars. Recent polar gullies in Sisyphi Cavi were also analyzed by [8], who estimated ages of about 20 ka to 20 Ma for the gullies. In this study we focus on a single gully in Sisyphi Cavi, located in the south polar region at 1.44° E and 68.54° S. The gully occurs on the gullied equator-facing slope of an isolated polar pit within an infilled impact crater. Multi-temporal high-resolution image data analyses show new deposits at the terminus of the gully channel and on the gully apron within spring (after solar longitudes of 236°) of martian years (MY) 29 and 31. In MY 29 deposition of material shortens the channel by about 40 m; in MY 31 a new deposit at the western flank of the gully apron with approximately 300-600 m3 of material is visible [3]. Our morphological investigations show that the identified new deposits were formed by dark flows through the entire gully deposited on top of the apron between LS ~218° and ~226°. Thermal data show a temperature increase between solar longitudes (LS) ~218° and ~226°. Near-infrared spectral data show relatively constant band strengths of CO2 ice and H2O ice in this time range. After the formation of the dark flows (after LS ~226°), temperatures increase rapidly from ~180 K to >~270 K at LS ~250°. At this time, spectral data indicate that all volatiles on the surface sublimated. However, an earlier beginning of sublimation when the dark flows were observed (between LS ~218° and ~226°) is likely, due to the fact that the instruments can only show the last phase of sublimation (decrease of volatile band strengths) [3]. Spectral modeling shows that from winter to mid-spring, the surface of the studied area is covered by CO2 slab

  6. Purification and characterization of multisquamase, the prothrombin activator present in Echis multisquamatus venom.

    PubMed

    Petrovan, R J; Govers-Riemslag, J W; Nowak, G; Hemker, H C; Rosing, J; Tans, G

    1997-11-01

    The venom of Echis multisquamatus (Central Asian sand viper) contains a single prothrombin activator, designated multisquamase, which is structurally and functionally different from ecarin, the prothrombin activator from the venom of Echis carinatus (saw-scaled viper). Multisquamase is comprised of a 58000 Mr and a 23000 Mr subunit that consists of two disulfide-linked chains of 12000 Mr and 10000 Mr, respectively. In contrast to ecarin, which activates prothrombin and prethrombin 1 at comparable rates, and whose activity is hardly affected by Ca2+ or by changes in ionic strength, multisquamase hardly activates prethrombin 1; prothrombin activation requires Ca2+ and is strongly inhibited at high ionic strength. The most favourable kinetic parameters are observed at 1 mM Ca2+ and at low ionic strength (Km=0.085 microM and kcat=0.68 s(-1) at I approximately 0.04). An increase in ionic strength considerably reduces the rate of prothrombin activation, due to an increase of the Km (Km=0.8 microM and kcat=1.03 s(-1) at I approximately 0.2). Studies in plasmas from patients on oral anticoagulant therapy show that E. Multisquamatus venom only activates carboxylated prothrombin, whereas E. carinatus activates both prothrombin and descarboxyprothrombin. Thus, multisquamase-dependent prothrombin activation appears to require post-translational modification of the gla-domain. This venom prothrombin activator may, therefore, become a useful tool to quantitate prothrombin and descarboxyprothrombin in cases where vitamin K-dependent carboxylation of prothrombin is impaired. PMID:9526951

  7. Geothermal activity at continental rift Citala, Western Mexico, where Lake Chapala is emplaced: past and present

    NASA Astrophysics Data System (ADS)

    Zárate-del Valle, P. F.

    2003-04-01

    Lake Chapala is a tectonic lake developed on a continental rift named Citala (CRC) which belongs to a tectonically active zone in Western Mexico: the so-called Jalisco continental triple junction. Fossil sinter deposit, thermal spring, hydrothermal (hy) petroleum manifestation and hy alteration halo characterized the Lake Chapala basin. On the SE shore, outcrops a carbonate deposit named ``La Calera" (LC) which consists of a carbonate fossil sinter that measures 2 km in E-W direction and 600 m in N-S direction and overlays andesitic rock. With a thickness of approximately 5 m and a roughly horizontal attitude, the LC is characterized by a two-fold structure: when massive, it is colored in yellow brownish and grey and elsewhere it shows a pseudo-brecciated structure and when banded, yellow and dark millimetre alternated bands can be seen. The LC is marked by vuggy porosity and silica (quartz and chalcedony) vein lets. Under microscope a pseudo-micritic texture is observed; vugs coated by iron oxides, are filled with calcite, and/or quartz, chalcedony and clay minerals. Six samples of LC were analysed (LODC-UParis VI) for their stable isotopes (δ18O and δ13C): From δ13C{PDB} values we have two sets of data: -8.03 to -8.69 ppm that means a no contribution of organic carbon (oc) and -0.35 to -0.75 ppm meaning an important contribution of oc; from δ18O{PDB} values: -8.5 to -10.27 ppm we deduced a deposit in meteoric water with a temperature deposition higher than the surface. The CRC is characterized also by the presence of hydrothermal petroleum (hp): Inside the Chapala and ˜2 km from SE shore (Los Arcos) there are some small spots made of hp which look like islands (<3-4 m^2) linked to the bottom of the lake which consist of solid bitumen. Thermal springs (ths) occur both inside and outside the lake Chapala: the water in out-shore ths is of carbonate type (69^oC; ˜ 240 mg L-1 [HCO_3]^-; with one exception: the ths at the San Juan Cosalá spa (N shore), which is

  8. GTP cyclohydrolase I expression and enzymatic activity are present in caveolae of endothelial cells

    PubMed Central

    Peterson, Timothy E.; d’Uscio, Livius V.; Cao, Sheng; Wang, Xiao-Li; Katusic, Zvonimir S.

    2009-01-01

    Tetrahydrobiopterin is an essential cofactor required for the synthesis of nitric oxide. GTP cyclohydrolase I (GTPCH I) is the rate limiting enzyme for tetrahydrobiopterin production in endothelial cells, yet little is known about the subcellular localization of this enzyme. In this study, we demonstrate that GTPCH I is localized to caveolar membrane microdomains along with caveolin-1 and endothelial nitric oxide synthase. GTPCH I activity was detected in isolated caveolar membranes from cultured endothelial cells. Confocal and electron microscopy analyses confirmed GTPCH I colocalization with caveolin-1. Consistent with in vitro studies, GTPCH I activity was evident in isolated caveolar microdomains from lung homogenates of wild-type mice. Importantly, a two-fold increase in GTPCH I activity was detected in the aortas of caveolin-1 deficient mice suggesting that caveolin-1 may be involved in the control of GTPCH I enzymatic activity. Indeed, overexpression of caveolin-1 inhibits GTPCH I activity, and tetrahydrobiopterin biosynthesis is activated by disruption of caveolae structure. These studies demonstrate that GTPCH I is targeted to caveolae microdomains in vascular endothelial cells and tetrahydrobiopterin production occurs in close proximity to endothelial nitric oxide synthase. Additionally, our findings provide new insights into the regulation of GTPCH I activity by the caveolar coat protein, caveolin-1. PMID:19104007

  9. Pattern formation for active particles on optically created ordered and disordered substrates (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Reichhardt, Charles M.; Ray, Dipanjan; Reichhardt, Cynthia J.

    2015-08-01

    There has been tremendous growth in the field of active matter, where the individual particles that comprise the system are self-driven. Examples of this class of system include biological systems such as swimming bacteria and crawling cells. More recently, non-biological swimmers have been created using colloidal Janus particles that undergo chemical reactions on one side to produce self-propulsion. These active matter systems exhibit a wide variety of behaviors that are absent in systems undergoing purely thermal fluctuations, such as transitions from uniform liquids to clusters or living crystals, pushing objects around, ratchet effects, and phase separation in mixtures of active and passive particles. Here we examine the collective effects of active matter disks in the presence of static or dynamic substrates. For colloids, such substrates could be created optically in the form of periodic, random, or quasiperiodic patterns. For thermal particles, increasing the temperature generally increases the diffusion or mobility of the particles when they move over a random or periodic substrates. We find that when the particles are active, increasing the activity can increase the mobility for smaller run lengths but decrease the mobility at large run lengths. Additionally we find that at large run lengths on a structured substrate, a variety of novel active crystalline states can form such as stripes, squares and triangular patterns.

  10. Biochemical and antimicrobial activity of phloretin and its glycosilated derivatives present in apple and kumquat.

    PubMed

    Barreca, Davide; Bellocco, Ersilia; Laganà, Giuseppina; Ginestra, Giovanna; Bisignano, Carlo

    2014-10-01

    Phloretin and its glycosylated derivatives (phlorizin and phloretin 3',5'-di-C-glucoside) are dihydrochalcones that have many interesting biological properties. The results obtained showed that the dihydrochalcones are able to inhibit growth of Gram positive bacteria, in particular Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 13932 and methicillin-resistant S. aureus clinical strains. Moreover, phloretin is active also against the Gram negative bacteria Salmonella typhimurium ATCC 13311. The determination of the enzymatic activity of key metabolic enzymes allowed us to shed some light on the biochemical mechanism of aglycon cell growth inhibition, showing as it remarkably influences the energetic metabolism of S. aureus. In addition, structure/activity determinations highlighted that the presence of a glycosyl moiety bound to the chalcone structure dramatically decreases the antimicrobial activity of phloretin. PMID:24799241

  11. Voluntary activation deficits of the infraspinatus present as a consequence of pitching-induced fatigue

    PubMed Central

    Gandhi, Jaipal; ElAttrache, Neal S.; Kaufman, Kenton R.; Hurd, Wendy J.

    2014-01-01

    Hypothesis Neuromuscular inhibition of the infraspinatus would be greater and external rotation muscle force would be lower after a simulated game compared with pregame values. Materials and methods The sample included 21 uninjured, asymptomatic high school–aged baseball pitchers. Maximum volitional shoulder external rotation strength was assessed before and after a simulated game with a clinical dynamometer. Voluntary activation of the infraspinatus was assessed during strength testing by a modified burst superimposition technique. Performance-related fatigue was assessed by monitoring pitch velocity, and global fatigue was assessed by subject self-report before and after the game. Statistical testing included paired and independent t tests, with α ≤ 05. Results There was no difference between throwing and non-throwing shoulder external rotation strength (P = .12) or voluntary infraspinatus activation (P = .27) before the game. After the game, voluntary activation was significantly lower in the throwing limb compared with pregame activation levels (P = .01). Lower external rotation strength after the game approached statistical significance (P =.06). Pitch velocity was lower in the final inning compared with first-inning velocity (P = .01), and fatigue was significantly greater after the game (P = .01). Conclusions Voluntary infraspinatus muscle activation is a mechanism contributing to external rotation muscle weakness in the fatigued pitcher. Understanding mechanisms contributing to muscle weakness is necessary to develop effective injury prevention and rehabilitation programs. Treatment techniques that enhance neuromuscular activation may be a useful strategy for enhancing strength in this population. Level of evidence Basic Science Study, Kinesiology Study. PMID:21831667

  12. Monitoring Target Engagement of Deubiquitylating Enzymes Using Activity Probes: Past, Present, and Future.

    PubMed

    Harrigan, Jeanine; Jacq, Xavier

    2016-01-01

    Deubiquitylating enzymes or DUBs are a class of enzymes that selectively remove the polypeptide posttranslational modification ubiquitin from a number of substrates. Approximately 100 DUBs exist in human cells and are involved in key regulatory cellular processes, which drive many disease states, making them attractive therapeutic targets. Several aspects of DUB biology have been studied through genetic knock-out or knock-down, genomic, or proteomic studies. However, investigation of enzyme activation and regulation requires additional tools to monitor cellular and physiological dynamics. A comparison between genetic ablation and dominant-negative target validation with pharmacological inhibition often leads to striking discrepancies. Activity probes have been used to profile classes of enzymes, including DUBs, and allow functional and dynamic properties to be assigned to individual proteins. The ability to directly monitor DUB activity within a native biological system is essential for understanding the physiological and pathological role of individual DUBs. We will discuss the evolution of DUB activity probes, from in vitro assay development to their use in monitoring DUB activity in cells and in animal tissues, as well as recent progress and prospects for assessing DUB inhibition in vivo. PMID:27613052

  13. Activation of photodynamic therapy in vitro with Cerenkov luminescence generated from Yttrium-90 (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hartl, Brad A.; Hirschberg, Henry; Marcu, Laura; Cherry, Simon R.

    2016-03-01

    Translation of photodynamic therapy to the clinical setting has primarily been limited to easily accessible and/or superficial diseases where traditional light delivery can be performed noninvasively. Cerenkov luminescence, as generated from medically relevant radionuclides, has been suggested as a means to deliver light to deeper tissues noninvasively in order to overcome this depth limitation. We report on the use of Cerenkov luminescence generated from Yttrium-90 as a means to active the photodynamic therapy process in monolayer tumor cell cultures. The current study investigates the utility of Cerenkov luminescence for activating both the clinically relevant aminolevulinic acid at 1.0 mM and also the more efficient photosensitizer TPPS2a at 1.2 µM. Cells were incubated with aminolevulinic acid for 6 hours prior to radionuclide addition, as well as additional daily treatments for three days. TPPS2a was delivered as a single treatment with an 18 hour incubation time before radionuclide addition. Experiments were completed for both C6 glioma cells and MDA-MB-231 breast tumor cells. Although aminolevulinic acid proved ineffective for generating a therapeutic effect at any activity for either cell line, TPPS2a produced at least a 20% therapeutic effect at activities ranging from 6 to 60 µCi/well for the C6 cell line. Current results demonstrate that it may be possible to generate a therapeutic effect in vivo using Cerenkov luminescence to activate the photodynamic therapy process with clinically relevant photosensitizers.

  14. Antibacterial activity of Pinus elliottii against anaerobic bacteria present in primary endodontic infections.

    PubMed

    Caetano da Silva, Sandro Donizete; Mendes de Souza, Maria Gorete; Oliveira Cardoso, Miguel Jorge; da Silva Moraes, Thais; Ambrósio, Sérgio Ricardo; Sola Veneziani, Rodrigo Cássio; Martins, Carlos Henrique G

    2014-12-01

    Endodontic infections have a polymicrobial nature, but anaerobic bacteria prevail among the infectious microbes. Considering that it is easy to eliminate planktonic bacteria, biofilm-forming bacteria still challenge clinicians during the fight against endodontic diseases. The chemical constituents of the oleoresin of Pinus elliottii, a plant belonging to the family Pinaceae, stand out in the search for biologically active compounds based on natural products with potential application in the treatment of endodontic infections. Indeed, plant oleoresins are an abundant natural source of diterpenes that display significant and well-defined biological activities as well as potential antimicrobial action. In this context, this study aimed to (1) evaluate the in vitro antibacterial activity of the oleoresin, fractions, and subfractions of P. elliottii as well as the action of dehydroabietic acid against 11 anaerobic bacteria that cause endodontic infection in both their planktonic and biofilm forms and (2) assess the in vitro antibiofilm activity of dehydroabietic acid against the same group of bacteria. The broth microdilution technique helped to determine the minimum inhibitory concentration (MIC) of the oleoresin and fractions. This same technique aided determination of the MIC values of nine subfractions of Fraction 1, the most active fraction. The MIC, minimum bactericidal concentration, and antibiofilm activity of dehydroabietic acid against the tested anaerobic bacteria were also examined. The oleoresin and fractions, especially fraction PE1, afforded promising MIC values, which ranged from 0.4 to 50 μg/mL. Concerning the nine evaluated subfractions, PE1.3 and PE1.4 furnished the most noteworthy MIC values, between 6.2 and 100 μg/mL. Dehydroabietic acid displayed antibacterial activity, with MIC values lying from 6.2 to 50 μg/mL, as well as bactericidal effect for all the investigated bacteria, except for Prevotella nigrescens. Assessment of the antibiofilm

  15. Active optical remote sensing of dense clouds with diffusing light : Early results, present implementations, and the challenges ahead

    SciTech Connect

    Davis, A. B.; Cahalan, R. F.; Winker, D. M.

    2002-01-01

    We survey the rapid progress of 'off-beam' cloud lidar, from inception to validation via laboratory-scale simulations. Cloud observations from ground, aircraft and even space are covered. Finally, we describe future work in this instrument development effort born out of pure theory in the mid-1990s. We foresee a bright future for off-beam lidar which is, in essence, an atmospheric application of the general principles of optical diffuse-light tomography. The physical cloud-boundary information it delivers is, in principle, the same as given from ground or space (upcoming CloudSat mission) obtained by mm-radar. And mm-radar gives some information about internal variability. However, radar reflectivities quite often disagree with optical estimates of cloud base and optical thickness for well-understood reasons. So optical and microwave cloud probes are now considered as complimentary rather then competitive in our efforts to better understand cloud radiative properties in the context of climate research. We are confident that off-beam lidar will be a valuable and, ultimately, cost-effective source of information about cloud processes. In this, we include direct insight into the present issues in large-scale short-wave absorption based on unambiguous geometrical pathlength statistics, a unique capability of off-beam cloud lidar.

  16. Images of Germany: Past and Present. A Film Collection, Series II Instructional Activities.

    ERIC Educational Resources Information Center

    Blankenship, Glen; Hutcheson, Gwen

    This booklet offers classroom activities for use with 15 social studies-related films for teaching about Germany. The series of 25-minute films are made available by Deutsche Welle Television and Goethe House New York. Lessons in the booklet include: (1) "Germany Since 1945: A Focus on Berlin"; (2) "'I'll Get You All Out of Here!' A Portrait of…

  17. Presenting Theoretical Ideas Prior to Inquiry Activities Fosters Theory-Level Knowledge

    ERIC Educational Resources Information Center

    Wecker, Christof; Rachel, Alexander; Heran-Dörr, Eva; Waltner, Christine; Wiesner, Hartmut; Fischer, Frank

    2013-01-01

    In the course of inquiry activities similar to those of real scientists, learners are supposed to develop knowledge both on the level of observable phenomena and on the level of explanatory theories. However, some theories involve theoretical entities (e.g., "Weiss domains") that cannot be observed directly and therefore may be hard to…

  18. Images of Germany, Past and Present: A Film Collection. Series I, Instructional Activities.

    ERIC Educational Resources Information Center

    Goethe House, New York, NY.

    This set of lessons accompanies a series of 30-minute films for teaching about Germany. Available to educators throughout the United States upon request, the 17 films and accompanying instructional activities focus on culture, politics, economics, society, and sports and are appropriate for middle and high school students. Permission is granted to…

  19. Production, characterization, and application of an organic solvent-tolerant lipase present in active inclusion bodies.

    PubMed

    Li, Suxia; Lin, Kang; Pang, Huaiyu; Wu, Yixin; Xu, Jianhe

    2013-01-01

    An organic solvent-tolerant lipase from Serratia marcescens ECU1010 (rSML) was overproduced in Escherichia coli in an insoluble form. High concentrations of both biomass (50 g cell wet weight/L culture broth) and inclusion bodies (10.5 g/L) were obtained by applying a high-cell-density cultivation procedure. Activity assays indicated that the enzymatic activity of rSML reached 600 U/L. After treatment with isopropyl ether for 12 h, the maximum lipase activity reached 6,000 U/L. Scanning electron microscopy and Fourier transform infrared microspectroscopy revealed the activation mechanism of rSML in the presence of organic solvents. rSML was stable in broad ranges of temperatures and pH values, as well as in a series of organic solvents. Besides, rSML showed the best enantioselectivity for the kinetic resolution of (±)-trans-3-(4-methoxyphenyl)glycidic acid methyl ester. These features render the S. marcescens ECU1010 lipase attractive for biotechnological applications in the field of organic synthesis and pharmaceutical industry. PMID:23269633

  20. Improved catalytic activity of rhodium monolayer modified nickel (110) surface for the methane dehydrogenation reaction: a first-principles study

    NASA Astrophysics Data System (ADS)

    Bothra, Pallavi; Pati, Swapan K.

    2014-05-01

    The catalytic activity of pure Ni (110) and single Rh layer deposited Ni (110) surface for the complete dehydrogenation of methane is theoretically investigated by means of gradient-corrected periodic density functional theory. A detailed kinetic study, based on the analysis of the optimal reaction pathway for the transformation of CH4 to C and H through four elementary steps (CH4 --> CH3 + H; CH3 --> CH2 + H; CH2 --> CH + H; CH -->C + H) is presented for pure Ni (110) and Rh/Ni (110) surfaces and compared with pure Rh (110) surface. Through systematic examination of adsorbed geometries and transition states, we show that single layer deposition of Rh on Ni (110) surface has a striking influence on lowering the activation energy barrier of the dehydrogenation reaction. Moreover, it is found that a pure Ni (110) surface has a tendency for carbon deposition on the catalytic surface during the methane dissociation reaction which decreases the stability of the catalyst. However, the deposition of carbon is largely suppressed by the addition of a Rh overlayer on the pure Ni (110) surface. The physical origin of stronger chemisorption of carbon on Ni (110) relative to Rh/Ni (110) has been elucidated by getting insight into the electronic structures and d-band model of the catalytic surfaces. Considering the balance in both the catalytic activity as well as the catalyst stability, we propose that the Rh/Ni (110) surface possesses much improved catalytic property compared to pure Ni (110) and pure Rh (110) surfaces.

  1. Questions and Answers for Ken Thomas' "Intra-Extra Vehicular Activity Russian and Gemini Spacesuits" Presentation

    NASA Technical Reports Server (NTRS)

    Thomas, Kenneth S.

    2016-01-01

    Kenneth Thomas will discuss the Intra-Extra Vehicular Activity Russian & Gemini spacesuits. While the United States and Russia adapted to existing launch- and reentry-type suits to allow the first human ventures into the vacuum of space, there were differences in execution and capabilities. Mr. Thomas will discuss the advantages and disadvantages of this approach compared to exclusively intravehicular or extra-vehicular suit systems.

  2. Present Research and Standardization Activities on Small Space Debris at Space Environment Prevention

    NASA Astrophysics Data System (ADS)

    Kitazawa, Yukihito; Hanada, Toshiya; Matsumoto, Haruhisa; Akahoshi, Yasuhiro; Higashide, Masumi; Okudaira, Osamu; Kamiya, Koki; Nitta, Kumi

    2016-07-01

    The micro-debris of the size from 100 μm to several mm is expected to cause a spacecraft critical failures and troubles. However, the collision probability of the micro-debris and its effect on space equipment are hardly predicted due to lack knowledge regarding the debris distribution and experimental/numerical investigation on material and components. This paper introduce research and standardization activities related on micro-debris for space environmental prevention

  3. Long-term facilitation of genioglossus activity is present in normal humans during NREM sleep

    PubMed Central

    Chowdhuri, Susmita; Pierchala, Lisa; Aboubakr, Salah E.; Shkoukani, Mahdi; Badr, M. Safwan

    2008-01-01

    Episodic hypoxia (EH) is followed by increased ventilatory motor output in the recovery period indicative of long-term facilitation (LTF). We hypothesized that episodic hypoxia evokes LTF of genioglossus (GG) muscle activity in humans during non-rapid eye movement sleep (NREM) sleep. We studied 12 normal non-flow limited humans during stable NREM sleep. We induced 10 brief (3 minute) episodes of isocapnic hypoxia followed by 5 minutes of room air. Measurements were obtained during control, hypoxia, and at 5, 10, 20, 30 and 40 minutes of recovery, respectively, for minute ventilation (V̇I), supraglottic pressure (PSG), upper airway resistance (RUA) and phasic GG electromyogram (EMGGG). In addition, sham studies were conducted on room air. During hypoxia there was a significant increase in phasic EMGGG (202.7±24.1% of control, p<0.01) and in V̇I (123.0±3.3% of control, p<0.05); however, only phasic EMGGG demonstrated a significant persistent increase throughout recovery (198.9±30.9%, 203.6±29.9% and 205.4±26.4% of control, at 5, 10, and 20 minutes of recovery, respectively, p<0.01). In multivariate regression analysis, age and phasic EMGGG activity during hypoxia were significant predictors of EMGGG at recovery 20 minutes. No significant changes in any of the measured parameters were noted during sham studies. Conclusion: 1) EH elicits LTF of GG in normal non-flow limited humans during NREM sleep, without ventilatory or mechanical LTF. 2) GG activity during the recovery period correlates with the magnitude of GG activation during hypoxia, and inversely with age. PMID:17945544

  4. Reduction of hexavalent chromium by Sphaerotilus natans a filamentous micro-organism present in activated sludges.

    PubMed

    Caravelli, Alejandro H; Giannuzzi, Leda; Zaritzky, Noemí E

    2008-08-15

    Wastewaters produced by various industries may contain undesirable amounts of hexavalent chromium (Cr(VI)), as chromate and dichromate, a hazardous metal affecting flora and animals of aquatic ecosystems as well as human health. One removal strategy comprises the microbial reduction of Cr(VI) to Cr(III), a less soluble chemical species that is less toxic than Cr(VI). In this work, the ability to reduce Cr(VI) of Sphaerotilus natans, a filamentous bacterium usually found in activated sludge systems, was evaluated. In aerobic conditions, S. natans was able to efficiently reduce Cr(VI) to Cr(III) from dichromate solutions ranging between 4.5 and 80 mg Cr(VI)l(-1) in the presence of a carbonaceous source. A simultaneous evaluation of the microbial respiratory activity inhibition was also carried out to analyze the toxic effect of Cr(VI). Cr(VI) reduction by S. natans was mathematically modeled; chromium(VI) reduction rate depended on both Cr(VI) concentration and active biomass concentration. Although it is known that S. natans removes heavy metal cations such as Cr(III) by biosorption, the ability of this micro-organism to reduce Cr(VI), which behaves as an oxyanion in aqueous solutions, is a novel finding. The distinctive capacity to reduce Cr(VI) to Cr(III) than remain soluble or precipitated becomes S. natans a potential micro-organism to decontaminate wastewaters. PMID:18215460

  5. Study of microparticles' anomalous diffusion in active bath using speckle light fields (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Pince, Ercag; Sabareesh, Sabareesh K. P.; Volpe, Giorgio; Gigan, Sylvain; Volpe, Giovanni S.

    2015-08-01

    Particles undergoing a stochastic motion within a disordered medium is a ubiquitous physical and biological phenomenon. Examples can be given from organelles as molecular machines of cells performing physical tasks in a populated cytoplasm to human mobility in patchy environment at larger scales. Our recent results showed that it is possible to use the disordered landscape generated by speckle light fields to perform advanced manipulation tasks at the microscale. Here, we use speckle light fields to study the anomalous diffusion of micron size silica particles (5 μm) in the presence of active microswimmers. The microswimmers we used in the experiments are motile bacteria, Escherichia coli (E.coli). They constitute an active background constantly agitating passive silica particles within complex optical potentials. The speckle fields are generated by mode mixing inside a multimode optical fiber where a small amount of incident laser power (maximum power = 12 μW/μm2) is needed to obtain an effective random landscape pattern for the purpose of optical manipulation. We experimentally show how complex potentials contribute to the anomalous diffusion of silica particles undergoing collisions with swimming bacteria. We observed an enhanced diffusion of particles interacting with the active bath of E.coli inside speckle light fields: this effect can be tuned and controlled by varying the intensity and the statistical properties of the speckle pattern. Potentially, these results could be of interest for many technological applications, such as the manipulation of microparticles inside optically disordered media of biological interests.

  6. A macromolecular crowding study of RNA folding and activity: polymer pore size matters! (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Börner, Richard; Fiorini, Erica; Paudel, Bishnu; Rueda, David; Sigel, Roland K. O.

    2016-03-01

    Catalytic RNAs, like the group IIB intron ribozyme of S. cerevesiae, require a high magnesium(II) concentration to show folding and function in vitro [1]. In contrast, in vivo conditions are characterized by a highly crowded cellular environment and much lower ion concentration. Molecular crowding agents are a widespread tool to mimic cellular crowding [2]. However, particular physical/chemical properties explaining the crowders influence are mostly not understood. In this study, we gain new insights on how polymer properties like viscosity, pore size etc. influence the activity and folding of a large RNA. We combined bulk activity assays and single-molecule Förster Resonance Energy Transfer experiments, screening the PEG volume fraction (%) and molecular weight (MW). Our results revealed that upon the influence of crowding agents, a compaction of the underlying structure depends on the PEG % and the presence of different PEG MW and % unveiled an optimal pore size in terms of catalytic activity. In summary, an increasing density of the crowding environment shifts the RNA towards the most compact state, but the ribozyme is only active if the crowders network matches its size [4]. We interpret the most compact state as necessary, but not sufficient, to keep the ribozyme active. Financial support from the European Research Council (MIRNA N° 259092, to RKOS), the Swiss National Fund (SNF), and the Forschungskredit Grant of the University of Zürich (FK-14-096 and 15-092 to RB) are gratefully acknowledged. [1] Swisher J.F., Su L.J., Brenowitz M., Anderson V.E., Pyle A.M., J. Mol. Bio., 315, 297-310 (2002). [2] Kilburn D., Roh J.H., Guo L., Briber R.M., Woodson S.A., JACS, 132, 8690-6 (2010). [3] Steiner M., Karunatilaka K.S., Sigel R.K.O., Rueda D., Proc. Natl. Acad. Sci. U.S.A.,105, 13853-8 (2008). [4] aBörner R, Fiorini E, Sigel R.K.O., Chimia, 69, 207-212 (2015).; bFiorini E., Paudel B., Börner R., Rueda D., Sigel R.K.O., submitted. [5] König S.L.B., Hadzic M

  7. Antibacterial, antifungal and antiprotozoal activities of fungal communities present in different substrates from Antarctica

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antarctica is a pristine and extreme environment that represents a unique opportunity for taxonomic, ecological and biotechnological studies of the microorganisms. In the present work, the fungal communities of rhizosphere soil of Deschampsia antarctica, soil, ornithogenic soil, marine and lake sedi...

  8. Speaking off the Cuff: Strategies and Activities for Developing Presentation Confidence

    ERIC Educational Resources Information Center

    Blaszczynski, Carol; Green, Diana J.

    2010-01-01

    Presentation mastery is a skill of paramount importance in the business world. The Partnership for 21st Century Skills has delineated the ability to "articulate thoughts and ideas effectively using oral, written and nonverbal skills in a variety of forms and contexts" as a student outcome under learning and innovation skills. Ability to think on…

  9. Modeling the Activities of Scientists: Prospective Science Teachers' Poster Presentations in An STS Course

    ERIC Educational Resources Information Center

    Dogan, Alev; Kaya, Osman Nafiz; Kilic, Ziya; Kilic, Esma; Aydogdu, Mustafa

    2004-01-01

    In this study, prospective science teachers' (PSTs) views about their poster presentations were investigated. These posters were developed through PSTs' online and library research and scientific mini-symposiums in chemistry related topics in the framework of science, technology and society course (STS). During the first four weeks of STS course,…

  10. Amygdala Activation during Masked Presentation of Emotional Faces Predicts Conscious Detection of Threat-Related Faces

    ERIC Educational Resources Information Center

    Suslow, Thomas; Ohrmann, Patricia; Bauer, Jochen; Rauch, Astrid Veronika; Schwindt, Wolfram; Arolt, Volker; Heindel, Walter; Kugel, Harald

    2006-01-01

    It has been argued that critical functions of the human amygdala are to modulate the moment-to-moment vigilance level and to enhance the processing and the consolidation of memories of emotionally arousing material. In this functional magnetic resonance study, pictures of human faces bearing fearful, angry, and happy expressions were presented to…

  11. US space flight experience. Physical exertion and metabolic demand of extravehicular activity: Past, present, and future

    NASA Technical Reports Server (NTRS)

    Moore, Thomas P.

    1989-01-01

    A review of physical exertion and metabolic demands of extravehicular activity (EVA) on U.S. astronauts is given. Information is given on EVA during Gemini, Apollo and Skylab missions. It is noted that nominal EVA's should not be overstressful from a cardiovascular standpoint; that manual-intensive EVA's such as are planned for the construction phase of the Space Station can and will be demanding from a muscular standpoint, primarily for the upper extremities; that off-nominal unplanned EVA's can be physically demanding both from an endurance and from a muscular standpoint; and that crewmembers should be physically prepared and capable of performing these EVA's at any time during the mission.

  12. Visions, Realities and Guiding Principles for the Future: A Talk Presented to the World Commission on Culture and Development at United Nations Headquarters, New York City, NY, April 1995.

    ERIC Educational Resources Information Center

    Lane, Phil, Jr.

    1995-01-01

    Reflects on challenges in establishing a new world civilization and outlines 16 principles for building sustainable, healthy, and spiritually balanced communities. Principles emerged from a 12-year process of reflection, consultation, and action within American Indian communities and are based on personal growth, social unity, spirituality, and…

  13. Nature of Catalytic Active Sites Present on the Surface of Advanced Bulk Tantalum Mixed Oxide Photocatalysts

    SciTech Connect

    Phivilay, Somphonh; Puretzky, Alexander A; Domen, Kazunari Domen; Wachs, Israel

    2013-01-01

    The most active photocatalyst system for water splitting under UV irradiation (270 nm) is the promoted 0.2%NiO/NaTaO3:2%La photocatalyst with optimized photonic efficiency (P.E.) of 56%, but fundamental issues about the nature of the surface catalytic active sites and their involvement in the photocatalytic process still need to be clarified. This is the first study to apply cutting edge surface spectroscopic analyses to determine the surface nature of tantalum mixed oxide photocatalysts. Surface analysis with HR-XPS (1-3nm) and HS-LEIS (0.3nm) spectroscopy indicates that the NiO and La2O3 promoters are concentrated in the surface region of the bulk NaTaO3 phase. The La2O3 is concentrated on the NaTaO3 outermost surface layers while NiO is distributed throughout the NaTaO3 surface region (1-3nm). Raman and UV-vis spectroscopy revealed that the bulk molecular and electronic structures, respectively, of NaTaO3 were not modified by the addition of the La2O3 and NiO promoters, with La2O3 resulting in a slightly more ordered structure. Photoluminescence (PL) spectroscopy reveals that the addition of La2O3 and NiO produces a greater number of electron traps resulting in the suppression of the recombination of excited electrons/holes. In contrast to earlier reports, the La2O3 is only a textural promoter (increasing the BET surface area ~7x by stabilizing smaller NaTaO3 particles), but causes a ~3x decrease in the specific photocatalytic TORs ( mol H2/m2/h) rate because surface La2O3 blocks exposed catalytic active NaTaO3 sites. The NiO promoter was found to be a potent electronic promoter that enhances the NaTaO3 surface normalized TORs by a factor of ~10-50 and TOF by a factor of ~10. The level of NiO promotion is the same in the absence and presence of La2O3 demonstrating that there is no promotional synergistic interaction between the NiO and La2O3 promoters. This study demonstrates the important contributions of the photocatalyst surface properties to the fundamental

  14. Marathon runners presented lower serum cholesteryl ester transfer activity than sedentary subjects.

    PubMed

    Serrat-Serrat, J; Ordóñez-Llanos, J; Serra-Grima, R; Gómez-Gerique, J A; Pellicer-Thoma, E; Payés-Romero, A; González-Sastre, F

    1993-06-01

    Acute exercise promotes raised HDL cholesterol concentrations by lipolysis stimulation, but this effect is insufficient to explain the more permanent HDL increases seen during regular exercise. During training periods in a group of marathon runners, we measured lipid transfer protein I (LTP-I)-mediated cholesteryl ester transfer activity (CETA) and its relationship to their HDL concentrations. Runners of both sexes showed significantly lower CETA values than those of sedentary controls. Male runners also had significantly lower serum concentrations of triglyceride, VLDL cholesterol and apolipoprotein B, and significantly higher concentrations of HDL cholesterol and apolipoprotein A-I than male controls. Results indicate that regular practice of aerobic exercise promotes modifications of lipoprotein metabolism related not only to lipolysis, but also to lower CETA. Such modifications are associated with reduced risk of atherosclerosis. PMID:8216501

  15. Effects of rhythmic stimulus presentation on oscillatory brain activity: the physiology of cueing in Parkinson's disease.

    PubMed

    te Woerd, Erik S; Oostenveld, Robert; Bloem, Bastiaan R; de Lange, Floris P; Praamstra, Peter

    2015-01-01

    The basal ganglia play an important role in beat perception and patients with Parkinson's disease (PD) are impaired in perception of beat-based rhythms. Rhythmic cues are nonetheless beneficial in gait rehabilitation, raising the question how rhythm improves movement in PD. We addressed this question with magnetoencephalography recordings during a choice response task with rhythmic and non-rhythmic modes of stimulus presentation. Analyses focused on (i) entrainment of slow oscillations, (ii) the depth of beta power modulation, and (iii) whether a gain in modulation depth of beta power, due to rhythmicity, is of predictive or reactive nature. The results show weaker phase synchronisation of slow oscillations and a relative shift from predictive to reactive movement-related beta suppression in PD. Nonetheless, rhythmic stimulus presentation increased beta modulation depth to the same extent in patients and controls. Critically, this gain selectively increased the predictive and not reactive movement-related beta power suppression. Operation of a predictive mechanism, induced by rhythmic stimulation, was corroborated by a sensory gating effect in the sensorimotor cortex. The predictive mode of cue utilisation points to facilitation of basal ganglia-premotor interactions, contrasting with the popular view that rhythmic stimulation confers a special advantage in PD, based on recruitment of alternative pathways. PMID:26509117

  16. Chloroformic and Methanolic Extracts of Olea europaea L. Leaves Present Anti-Inflammatory and Analgesic Activities

    PubMed Central

    Chebbi Mahjoub, R; Khemiss, M.; Dhidah, M.; Dellaï, A.; Bouraoui, A.; Khemiss, F.

    2011-01-01

    Olea europaea L. is used in traditional medicine in the Mediterranean areas. Its natural products are used in the treatment of different disorders, like fighting fever and some infectious diseases such as malaria, the treatment of arrhythmia, and relief of intestinal spasms. The aim of the current study is to investigate the possible anti-inflammatory and anatinociceptive effects of methanol and chloroformic extracts prepared from leaves of Olea europaea L. The anti-inflammatory and antinociceptive effects of the different extracts of Olea europaea leaves were assessed after intraperitoneal administration into rats and mice, using the carrageenan-induced paw edema model in rats to test the anti-inflammatory effect and the acetic acid-induced writhing in mice to test the analgesic effect. The chloroformic and methanolic leaves extracts, studied at the doses of 50, 100, and 200 mg/kg (Body Weight: BW), exhibited significant dose-dependent anti-inflammatory and analgesic activities. Based on the results obtained, it can be concluded that Olea europaea leaves extracts have anti-inflammatory and antinociceptive effects. PMID:22084717

  17. Weather Regimes and cyclonic activity in the North Atlantic European region: present and future climates

    NASA Astrophysics Data System (ADS)

    Rodrigues, Tiago; Rocha, Alfredo; Melo-Gonçalves, Paulo; Santos, João A.; Pinto, Joaquim G.

    2014-05-01

    Damages associated with extratropical storms are amongst the most important natural hazards on Western Europe. Thus, in this work we analyse: (i) the relationships between several cyclone characteristics: intensity, depth, radius, cyclogenesis, cyclolysis, and total number of cyclones (identified by applying the Murray and Simmonds method to 6-hourly 850 hPa geopotential height); (ii) their links to four large-scale weather regimes (WRs) over a North Atlantic-European sector (NAE, 90W-30E, 20N-80N); and (iii) the projected changes for future climates under emission scenarios. Four WRs are identified by a 4-means clustering of the daily 500 hPa geopotential height fields (Blocking, Zonal or NAO+, Atlantic Ridge, and Greenland Anticyclonic). Furthermore, daily 500 hPa geopotential height from four CMIP3 simulations are clustered using the ERA centroids, for both the recent-past climate (1961-1990) and two future climates: 2021-2050 and 2069-2098. The impact of anthropogenic forcing on the cyclonic activity over the NAE sector is thereby quantified for each of the four weather regimes. Acknowledgments: this work is supported by European Union Funds (FEDER/COMPETE - Operational Competitiveness Programme) and by national funds (FCT - Portuguese Foundation for Science and Technology) under the project CLIPE (PTDC/AAC-CLI/111733/2009).

  18. Present status of research activities relating global warming problems in Japan (mainly MITI and relating organizations)

    SciTech Connect

    Yokoyama, O.

    1993-12-31

    Japanese government has issued action program so called {open_quotes}Action Program to Arrest Global Warming{close_quotes} for preventing global warming at Oct., 1990. According to the program, CO{sub 2} emission should be stabilized on a per capita basis in the year 2000 and beyond at about same level as in 2000 by introducing several methods such as energy conservation, improvement of energy using efficiency, expanding use of renewable energy and so on. The basic concept, target and methods are summarized. At the same time, MITI published so called {open_quotes}New Earth 21{close_quotes} project which aims remedying the earth environment modified by human activities since industrial innovation began at about 200 years ago in coming 100 years. This plan proposed yearly step of research development of technology for mitigating CO{sub 2} emission. According to the MITI`s plan, 15 institutions belonging to AIST have carrying research for developing technology of reducing emission of CO{sub 2} and other greenhouse gases, with cooperation of other research organizations such as RITE (research Institute of Innovative Technology for Earth) and NEDO (New Energy and Industrial Technology Developing Organization). Time schedule of the research development by The New Earth 21 project is summarized in Table 2. Now, in Japan, many national institutions and universities, research works relating reduction and mitigation of GHG are carried out according to this guideline.

  19. Magnetic recovery of modified activated carbon powder used for removal of endocrine disruptors present in water.

    PubMed

    Borghi, Chiara Caterina; Fabbri, Massimo

    2014-01-01

    This paper was aimed at studying sustainable solutions for the treatment of water polluted by octylphenols and nonylphenols that are xenoextrogen compounds affecting human health and dangerous for the aquatic environment. We studied the removal of 4-octylphenol and 4-n-nonylphenol with concentrations of the order of 5-10 mg/l on a laboratory scale. A mixing time of 10 min with 0.1 g/l of magnetic-activated carbons (MACs) was enough to obtain 95 +/- 5% adsorption of both 4-octylphenol and 4-n-nonylphenol. The adsorption of the surfactants IGEPAL CO-630 and TRITON X-100, which are precursors of branched 4-nonylphenol and the carcinogenic 4-tert-octylphenol, respectively, was also studied using the same technique. For concentrations between 2 and 10mg/l of these alkylphenols ethoxylated, after 10min mixing with 0.5 g/l of MACs, a 95 +/- 5% adsorption was obtained. A 97 +/- 1% removal of MACs was achieved after 10min of continuous-flow magnetic filtration (14.5 l/min). The filter used was made of SUS440C magnetic steel spheres. Srm-Co permanent magnets provided a uniform flux density field of about 500 mT. PMID:24645486

  20. Gender difference in electrical brain activity during presentation of various film excerpts with different emotional content.

    PubMed

    Dimpfel, W; Wedekind, W; Keplinger, I

    2003-05-30

    Electrical activity of the human brain has been monitored using socalled charge mode (Laplacian estimates) during the exposure with short video film excerpts of 7 min duration. Eighty subjects (50% male and female) watched 5 different film excerpts (disney, animal, comedy, erotic and sex scenes) separated by 3 min pause. Comparison to a reference period of 7 min without video exposure revealed strong decreases in alpha and beta power starting from the electrode position T6 (right temporal) and spread to other brain areas with stronger attentional stimuli e.g. during the erotic and sex films. Highly statistically significant differences were observed between male and female in temporal areas, who in general developed stronger decreases than males. Females on the other hand produced significant increases in fronto-central delta and theta power which could be interpreted as expression of higher appreciation, whereas the decreases in alpha power in general are understood as signs of higher attention. The data are further proof that recording the computer aided quantitative EEG is a very fruitful and promising approach in psychophysiology. PMID:12844473

  1. Activity-guided identification of acetogenins as novel lipophilic antioxidants present in avocado pulp (Persea americana).

    PubMed

    Rodríguez-Sánchez, Dariana; Silva-Platas, Christian; Rojo, Rocío P; García, Noemí; Cisneros-Zevallos, Luis; García-Rivas, Gerardo; Hernández-Brenes, Carmen

    2013-12-30

    Avocado fruit is a rich source of health-related lipophilic phytochemicals such as monounsaturated fatty acids, tocopherols, carotenes, acetogenins and sterols. However, limited information is available on the contribution of specific phytochemicals to the overall antioxidant capacity (AOC) of the fruit. Centrifugal partition chromatography was used as fractionation tool, guided by an in vitro chemical assay of oxygen radical absorbance capacity (ORAC). Subsequent experiments focused on isolation and characterization of the chemical nature of the main contributors to lipophilic AOC of avocado pulp. ORAC values obtained for acetogenins were contrasted with results from an isolated kidney mitochondria membrane lipid peroxidation bioassay. The present study established that lipophilic AOC of the pulp was significantly higher than its hydrophilic AOC. Our results confirmed the presence of acetogenins in the fractions with highest lipophilic AOC, and for the first time linked them as contributors to lipophilic-ORAC values. Further HPLC-PDA/MS-TOF analysis led to structural elucidation of two novel acetogenins, not previously reported as present in avocado pulp, along with five already known related-compounds. Antioxidant properties observed for avocado pulp acetogenins by the ORAC assay suggested that, in the presence of an emulsifying agent, acetogenins could serve as novel lipophilic antioxidants in a food matrix. Results from isolated mitochondria lipid peroxidation bioassay, indicated that L-ORAC values which may have relevance for food matrix applications, should not be interpreted to have a direct relevance in health-related claims, compounds need to be evaluated considering the complexity of biological systems. PMID:24211333

  2. Decreasing the singlet-triplet gap for thermally activated delayed fluorescence molecules by structural modification on the donor fragment: First-principles study

    NASA Astrophysics Data System (ADS)

    Fan, Jian-zhong; Lin, Li-li; Wang, Chuan-kui

    2016-05-01

    The small energy gap between singlet excitons (S) and triplet excitons (T) of organic molecules is a dominant condition for high efficient thermally activated delayed fluorescence (TADF). In this study, influence of modification in donor groups of a series of molecules on their geometries, S-T energy gaps, and photophysical properties, is investigated based on first-principles calculations. Investigation shows that, as the electron donating ability is increased, both S-T energy gap and overlap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are decreased. This work provides strategy for designing high efficient and multi-color TADF devices.

  3. Engaging Stakeholders From Volunteer-Led Out-of-School Time Programs in the Dissemination of Guiding Principles for Healthy Snacking and Physical Activity

    PubMed Central

    Koomas, Alyssa; Metayer, Nesly; Fullerton, Karen J.; Hubbard, Kristie L.; Anzman-Frasca, Stephanie; Hofer, Teresa; Nelson, Miriam; Newman, Molly; Sacheck, Jennifer; Economos, Christina

    2015-01-01

    Background Little effort has focused on the role of volunteer-led out-of-school time (OST) programs (ie, enrichment and sports programs) as key environments for the promotion of healthy eating and physical activity habits among school-aged children. The Healthy Kids Out of School (HKOS) initiative developed evidence-based, practical guiding principles for healthy snacks, beverages, and physical activity. The goal of this case study was to describe the methods used to engage regional partners to understand how successful implementation and dissemination of these principles could be accomplished. Community Context HKOS partnered with volunteer-led programs from 5 OST organizations in Maine, Massachusetts, and New Hampshire to create a regional “learning laboratory.” Methods We engaged partners in phases. In the first phase, we conducted focus groups with local volunteer program leaders; during the second phase, we held roundtable meetings with regional and state program administrators; and in the final phase, we conducted additional outreach to refine and finalize implementation strategies. Outcomes Implementation strategies were developed based on themes and information that emerged. For enrichment programs, strategies included new patch and pin programs that were consistent with the organizations’ infrastructure and usual practices. For sports programs, the main strategy was integration with online trainings for coaches. Interpretation Through the engagement process, we learned that dissemination of the guiding principles in these large and complex OST organizations was best accomplished by using implementation strategies that were customized, integrated, and aligned with goals and usual practices. The lessons learned can benefit future efforts to prevent obesity in complex environments. PMID:26704443

  4. Determination of oenothein B as the active 5-alpha-reductase-inhibiting principle of the folk medicine Epilobium parviflorum.

    PubMed

    Lesuisse, D; Berjonneau, J; Ciot, C; Devaux, P; Doucet, B; Gourvest, J F; Khemis, B; Lang, C; Legrand, R; Lowinski, M; Maquin, P; Parent, A; Schoot, B; Teutsch, G

    1996-05-01

    Several extracts from Epilobium parviflorum, a plant used in Central Europe for the treatment of prostate disorders, were evaluated in a biochemical assay with 5-alpha-reductase. The aqueous extract displaying inhibition of the enzyme was analyzed, the fraction responsible for this activity was purified, and the active compound identified as a macrocyclic tannin, oenothein B (1). PMID:8778238

  5. The P3 produced by auditory stimuli presented in a passive and active condition: modulation by visual stimuli.

    PubMed

    Wronka, Eligiusz; Kuniecki, Michał; Kaiser, Jan; Coenen, Anton M L

    2007-01-01

    The aim of this study was to investigate how the processing of auditory stimuli is affected by the simultaneous presentation of visual stimuli. This was approached in an active and passive condition, during which a P3 was elicited in the human EEG by single auditory stimuli. Subjects were presented tones, either alone or accompanied by the simultaneous exposition of pictures. There were two different sessions. In the first, the presented tones demanded no further cognitive activity from the subjects (passive or 'ignore' session), while in the second session subjects were instructed to count the tones (active or 'count' session). The central question was whether inter-modal influences of visual stimulation in the active condition would modulate the auditory P3 in the same way as in the passive condition. Brain responses in the ignore session revealed only a small P3-like component over the parietal and frontal cortex, however, when the auditory stimuli co-occurred with the visual stimuli, an increased frontal activity in the window of 300-500 ms was observed. This could be interpreted as the reflection of a more intensive involuntary attention shift, provoked by the preceding visual stimulation. Moreover, it was found that cognitive load caused by the count instruction, resulted in an evident P3, with maximal amplitude over parietal locations. This effect was smaller when auditory stimuli were presented on the visual background. These findings might support the thesis that available resources were assigned to the analysis of visual stimulus, and thus were not available to analyze the subsequent auditory stimuli. This reduction in allocation of resources for attention was restricted to the active condition only, when the matching of a template with incoming information results in a distinct P3 component. It is discussed whether the putative source of this effect is a change in the activity of the frontal cortex. PMID:17691223

  6. Basic Comfort Heating Principles.

    ERIC Educational Resources Information Center

    Dempster, Chalmer T.

    The material in this beginning book for vocational students presents fundamental principles needed to understand the heating aspect of the sheet metal trade and supplies practical experience to the student so that he may become familiar with the process of determining heat loss for average structures. Six areas covered are: (1) Background…

  7. Principles of Biomedical Ethics

    PubMed Central

    Athar, Shahid

    2012-01-01

    In this presentation, I will discuss the principles of biomedical and Islamic medical ethics and an interfaith perspective on end-of-life issues. I will also discuss three cases to exemplify some of the conflicts in ethical decision-making. PMID:23610498

  8. Fermat's Principle Revisited.

    ERIC Educational Resources Information Center

    Kamat, R. V.

    1991-01-01

    A principle is presented to show that, if the time of passage of light is expressible as a function of discrete variables, one may dispense with the more general method of the calculus of variations. The calculus of variations and the alternative are described. The phenomenon of mirage is discussed. (Author/KR)

  9. Raman-active modes of a-GeSe2 and a-GeS2: A first-principles study

    NASA Astrophysics Data System (ADS)

    Jackson, Koblar; Briley, Arlin; Grossman, Shau; Porezag, Dirk V.; Pederson, Mark R.

    1999-12-01

    We have used a recently developed computational technique based on density-functional theory to study the Raman-active modes of amorphous GeSe2 and GeS2. Vibrational modes and the associated Raman activities for three cluster building blocks of the glasses are calculated directly from first principles. The positions of the calculated symmetric-stretch modes in the cluster models are in excellent agreement with sharp features in the observed spectra. Moreover, simulated spectra based on the cluster results are in good agreement with experiment, accounting for all the observed features in the bond-stretch region of the spectra. The cluster results suggest a new interpretation for the 250 cm-1 mode appearing in the spectra of Ge-rich samples in the GexS1-x family.

  10. Recent advances in biologically active compounds in herbs and spices: a review of the most effective antioxidant and anti-inflammatory active principles.

    PubMed

    Rubió, Laura; Motilva, Maria-José; Romero, Maria-Paz

    2013-01-01

    Spices, like vegetables, fruit, and medicinal herbs, are known to possess a variety of antioxidant effects and other biological activities. Phenolic compounds in these plant materials are closely associated with their antioxidant activity, which is mainly due to their redox properties and their capacity to block the production of reactive oxygen species. More recently, their ability to interfere with signal transduction pathways involving various transcription factors, protein kinases, phosphatases, and other metabolic enzymes has also been demonstrated. Many of the spice-derived compounds which are potent antioxidants are of great interest to biologists and clinicians because they may help protect the human body against oxidative stress and inflammatory processes. It is important to study the bioactive compounds that can modulate target functions related to defence against oxidative stress, and that might be used to achieve health benefits individually. In the present review, an attempt has been made to summarize the most current scientific evidence about the in vitro and in vivo effects of the bioactive compounds derived from herbs and spices, focused on anti-inflammatory and antioxidant effects, in order to provide science-based evidence for the traditional uses and develop either functional foods or nutraceuticals. PMID:23768186

  11. International Perspectives on Adapted Physical Activity. Selected Papers Presented at the International Symposium on Adapted Physical Activity (5th, Toronto, Canada, October 1-4, 1985).

    ERIC Educational Resources Information Center

    Berridge, Mavis E., Ed.; Ward, Graham R., Ed.

    The 36 papers in this book were presented at the Fifth International Symposium on Adapted Physical Activity. Presentations document some of the research findings and new ideas in physical education and recreation programs designed to improve the quality of life for special populations. The collection represents the breadth of the field, from the…

  12. Principles of lysosomal membrane digestion: stimulation of sphingolipid degradation by sphingolipid activator proteins and anionic lysosomal lipids.

    PubMed

    Kolter, Thomas; Sandhoff, Konrad

    2005-01-01

    Sphingolipids and glycosphingolipids are membrane components of eukaryotic cell surfaces. Their constitutive degradation takes place on the surface of intra-endosomal and intra-lysosomal membrane structures. During endocytosis, these intra-lysosomal membranes are formed and prepared for digestion by a lipid-sorting process during which their cholesterol content decreases and the concentration of the negatively charged bis(monoacylglycero)phosphate (BMP)--erroneously also called lysobisphosphatidic acid (LBPA)--increases. Glycosphingolipid degradation requires the presence of water-soluble acid exohydrolases, sphingolipid activator proteins, and anionic phospholipids like BMP. The lysosomal degradation of sphingolipids with short hydrophilic head groups requires the presence of sphingolipid activator proteins (SAPs). These are the saposins (Saps) and the GM2 activator protein. Sphingolipid activator proteins are membrane-perturbing and lipid-binding proteins with different specificities for the bound lipid and the activated enzyme-catalyzed reaction. Their inherited deficiency leads to sphingolipid- and membrane-storage diseases. Sphingolipid activator proteins not only facilitate glycolipid digestion but also act as glycolipid transfer proteins facilitating the association of lipid antigens with immunoreceptors of the CD1 family. PMID:16212488

  13. The Energy Challenge: An Activity Master Program About our Energy Past, Present, and Future for Grades 5 Through 8.

    ERIC Educational Resources Information Center

    Federal Energy Administration, Washington, DC.

    This publication presents 24 spirit duplicating activity masters and background materials for energy education in grades 5 through 8. These interdisciplinary materials are arranged in 6 units. Unit titles are: (1) Energy Overview; (2) Fossil Fuels - Coal, Oil, and Natural Gas; (3) Energy Resources for Today and Tomorrow; (4) Energy Conservation;…

  14. Principles of Bioremediation Assessment

    NASA Astrophysics Data System (ADS)

    Madsen, E. L.

    2001-12-01

    Although microorganisms have successfully and spontaneously maintained the biosphere since its inception, industrialized societies now produce undesirable chemical compounds at rates that outpace naturally occurring microbial detoxification processes. This presentation provides an overview of both the complexities of contaminated sites and methodological limitations in environmental microbiology that impede the documentation of biodegradation processes in the field. An essential step toward attaining reliable bioremediation technologies is the development of criteria which prove that microorganisms in contaminated field sites are truly active in metabolizing contaminants of interest. These criteria, which rely upon genetic, biochemical, physiological, and ecological principles and apply to both in situ and ex situ bioremediation strategies include: (i) internal conservative tracers; (ii) added conservative tracers; (iii) added radioactive tracers; (iv) added isotopic tracers; (v) stable isotopic fractionation patterns; (vi) detection of intermediary metabolites; (vii) replicated field plots; (viii) microbial metabolic adaptation; (ix) molecular biological indicators; (x) gradients of coreactants and/or products; (xi) in situ rates of respiration; (xii) mass balances of contaminants, coreactants, and products; and (xiii) computer modeling that incorporates transport and reactive stoichiometries of electron donors and acceptors. The ideal goal is achieving a quantitative understanding of the geochemistry, hydrogeology, and physiology of complex real-world systems.

  15. Hands-on Activities versus Worksheets in Reinforcing Physical Science Principles: Effects on Student Achievement and Attitude.

    ERIC Educational Resources Information Center

    Johnson, Donald M.; Wardlow, George W.; Franklin, Timothy D.

    1997-01-01

    A group of 132 agricultural science students were divided into an experimental group who completed hands-on activities on Ohm's Law and incline plane and a control group who completed worksheets. There were no significant differences in immediate or follow-up measures of achievement. Hands-on students had significantly more positive attitudes. (SK)

  16. Elements and Principles of Design Posters. Teacher's Guide.

    ERIC Educational Resources Information Center

    1996

    This book accompanies a poster series and allows the teacher to pre-plan a lesson or activity for students with the objectives shown for each element or principle of design to be presented. Along with a black-and-white reproduction of each poster, major concepts are discussed. Suggested student activities relating to a particular element or…

  17. First principles investigation of the activity of thin film Pt, Pd and Au surface alloys for oxygen reduction.

    PubMed

    Tripkovic, Vladimir; Hansen, Heine Anton; Rossmeisl, Jan; Vegge, Tejs

    2015-05-01

    Further advances in fuel cell technologies are hampered by kinetic limitations associated with the sluggish cathodic oxygen reduction reaction. We have investigated a range of different formulations of binary and ternary Pt, Pd and Au thin films as electrocatalysts for oxygen reduction. The most active binary thin films are near-surface alloys of Pt with subsurface Pd and certain PdAu and PtAu thin films with surface and/or subsurface Au. The most active ternary thin films are with pure metal Pt or Pd skins with some degree of Au in the surface and/or subsurface layer and the near-surface alloys of Au with mixed Pt-Pd skins. The activity of the binary and ternary catalysts is explained through weakening of the OH binding energy caused by solute elements. However, given the low alloy formation energies it may be difficult to tune and retain the composition under operating conditions. This is particularly challenging for alloys containing Au due to a high propensity of Au to segregate to the surface. We also show that once Au is on the surface it will diffuse to defect sites, explaining why small amounts of Au retard dissolution of Pt nanoparticles. For the PtPd thin films there is no pronounced driving force for surface segregation, diffusion to defects or surface self-assembling. On the basis of stability and activity analysis we conclude that the near surface alloy of Pd in Pt and some PdAu binary and PtPdAu ternary thin films with a controlled amount of Au are the best catalysts for oxygen reduction. PMID:25865333

  18. Comparison of the simple cyclic voltammetry (CV) and DPPH assays for the determination of antioxidant capacity of active principles.

    PubMed

    Arteaga, Jesús F; Ruiz-Montoya, Mercedes; Palma, Alberto; Alonso-Garrido, Gema; Pintado, Sara; Rodríguez-Mellado, José M

    2012-01-01

    Antioxidant activity of a number of small (low molecular weight) natural compounds found in spices, condiments or drugs (gallic acid, sesamol, eugenol, thymol, carvacrol, vanillin, salicylaldehyde, limonene, geraniol, 4-hexylresorcinol, etc.) has been evaluated using electrochemical and DPPH• radical scavenging measurements. Structural analysis of the tested compound suggest a remarkable activity for phenol derivatives and the importance of the -R groups located on the phenolic ring in the molecule's ability to act as free radical scavenging as well as their influence in the electrochemical behavior. The voltammetric method can be used for the determination of the antioxidant capability in the same manner as the DPPH• radical scavenging because of the correlation found between oxidation potentials and anti-radical power (ARP = 1/EC₅₀). Such electrochemical determination is fast and cheap and allows making measurements under a variety of experimental conditions. The accuracy of the electrochemical measurements is the same for all the compounds, irrespective of their scavenging activity, the opposite of what occurs in the DPPH• test. PMID:22555300

  19. Children's Understanding of Conversational Principles.

    ERIC Educational Resources Information Center

    Conti, Daniel J.; Camras, Linda A.

    1984-01-01

    Investigates the development of awareness of conversational principles in preschool, first-, and third-grade children by presenting them with short stories ending with a verbal statement by a story character. Results suggest that children's understanding of conversational principles improves considerably between preschool and first grade.…

  20. A Crystallin Fold in the Interleukin-4-inducing Principle of Schistosoma mansoni Eggs (IPSE/α-1) Mediates IgE Binding for Antigen-independent Basophil Activation*

    PubMed Central

    Meyer, N. Helge; Mayerhofer, Hubert; Tripsianes, Konstantinos; Blindow, Silke; Barths, Daniela; Mewes, Astrid; Weimar, Thomas; Köhli, Thies; Bade, Steffen; Madl, Tobias; Frey, Andreas; Haas, Helmut; Mueller-Dieckmann, Jochen; Sattler, Michael; Schramm, Gabriele

    2015-01-01

    The IL-4-inducing principle from Schistosoma mansoni eggs (IPSE/α-1), the major secretory product of eggs from the parasitic worm S. mansoni, efficiently triggers basophils to release the immunomodulatory key cytokine interleukin-4. Activation by IPSE/α-1 requires the presence of IgE on the basophils, but the detailed molecular mechanism underlying activation is unknown. NMR and crystallographic analysis of IPSEΔNLS, a monomeric IPSE/α-1 mutant, revealed that IPSE/α-1 is a new member of the βγ-crystallin superfamily. We demonstrate that this molecule is a general immunoglobulin-binding factor with highest affinity for IgE. NMR binding studies of IPSEΔNLS with the 180-kDa molecule IgE identified a large positively charged binding surface that includes a flexible loop, which is unique to the IPSE/α-1 crystallin fold. Mutational analysis of amino acids in the binding interface showed that residues contributing to IgE binding are important for IgE-dependent activation of basophils. As IPSE/α-1 is unable to cross-link IgE, we propose that this molecule, by taking advantage of its unique IgE-binding crystallin fold, activates basophils by a novel, cross-linking-independent mechanism. PMID:26163514

  1. Principles for Constructing Good Clicker Questions: Going beyond Rote Learning and Stimulating Active Engagement with Course Content

    ERIC Educational Resources Information Center

    Sullivan, Roberta

    2009-01-01

    Clickers are also referred to as classroom response systems. They are small-handheld electronic devices that resemble a television remote control, used by students to respond to questions posed by instructors. Typically, questions are provided to students using electronic on-screen presentations. Results of students' responses can be immediately…

  2. First-Principles Design of Graphene-Based Active Catalysts for Oxygen Reduction and Evolution Reactions in the Aprotic Li-O2 Battery.

    PubMed

    Kang, Joonhee; Yu, Jong-Sung; Han, Byungchan

    2016-07-21

    Using first-principles density functional theory (DFT) calculations, we demonstrate that catalytic activities toward oxygen reduction and evolution reactions (ORR and OER) in a Li-O2 battery can be substantially improved with graphene-based materials. We accomplish the goal by calculating free energy diagrams for the redox reactions of oxygen to identify a rate-determining step controlling the overpotentials. We unveil that the catalytic performance is well described by the adsorption energies of the intermediates LiO2 and Li2O2 and propose that graphene-based materials can be substantially optimized through either by N doping or encapsulating Cu(111) single crystals. Furthermore, our systematic approach with DFT calculations applied to design of optimum catalysts enables screening of promising candidates for the oxygen electrochemistry leading to considerable improvement of efficiency of a range of renewable energy devices. PMID:27392527

  3. Trans-presentation of IL-15 modulates STAT5 activation and Bcl-6 expression in TH1 cells

    PubMed Central

    Cooley, Ian D.; Read, Kaitlin A.; Oestreich, Kenneth J.

    2015-01-01

    During infection, naïve CD4+ T helper cells differentiate into specialized effector subsets based upon environmental signals propagated by the cytokine milieu. Recently, this paradigm has been complicated by the demonstration that alterations in the cytokine environment can result in varying degrees of plasticity between effector T helper cell populations. Therefore, elucidation of the mechanisms by which cytokines regulate T helper cell differentiation decisions is increasingly important. The gamma common cytokine IL-15 is currently undergoing clinical trials for the treatment of malignancies, due to its well-established role in the regulation of natural killer and CD8+ T cell immune responses. However, the effect of IL-15 signaling on CD4+ T cell activity is incompletely understood. One mechanism by which IL-15 activity is conferred is through trans-presentation via the IL-15 receptor alpha subunit. Here, we demonstrate that differentiated TH1 cells are responsive to trans-presented IL-15. Importantly, while trans-presentation of IL-15 results in STAT5 activation and maintenance of the TH1 gene program, IL-15 treatment alone allows for increased Bcl-6 expression and the upregulation of a TFH-like profile. Collectively, these findings describe a novel role for IL-15 in the modulation of CD4+ T cell responses and provide valuable insight for the use of IL-15 in immunotherapeutic approaches. PMID:26500048

  4. Geometries and electronic structures of the hydrogenated diamond (100) surface upon exposure to active ions: A first principles study

    NASA Astrophysics Data System (ADS)

    Liu, Feng-Bin; Li, Jing-Lin; Chen, Wen-Bin; Cui, Yan; Jiao, Zhi-Wei; Yan, Hong-Juan; Qu, Min; Di, Jie-Jian

    2016-02-01

    To elucidate the effects of physisorbed active ions on the geometries and electronic structures of hydrogenated diamond films, models of HCO 3 - , H3O+, and OH- ions physisorbed on hydrogenated diamond (100) surfaces were constructed. Density functional theory was used to calculate the geometries, adsorption energies, and partial density of states. The results showed that the geometries of the hydrogenated diamond (100) surfaces all changed to different degrees after ion adsorption. Among them, the H3O+ ion affected the geometry of the hydrogenated diamond (100) surfaces the most. This is well consistent with the results of the calculated adsorption energies, which indicated that a strong electrostatic attraction occurs between the hydrogenated diamond (100) surface and H3O+ ions. In addition, electrons transfer significantly from the hydrogenated diamond (100) surface to the adsorbed H3O+ ion, which induces a downward shift in the HOMO and LUMO energy levels of the H3O+ ion. However, for active ions like OH- and HCO 3 - , no dramatic change appears for the electronic structures of the adsorbed ions.

  5. Different Citrus rootstocks present high dissimilarities in their antioxidant activity and vitamins content according to the ripening stage.

    PubMed

    Cardeñosa, Vanessa; Barros, Lillian; Barreira, João C M; Arenas, Francisco; Moreno-Rojas, José M; Ferreira, Isabel C F R

    2015-02-01

    "Lane Late" sweet orange grafted on six different citrus rootstocks and grown in the Guadalquivir valley (Seville, Spain) were picked at different ripening stages in two consecutive seasons to characterize their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and quantify their main antioxidant compounds (vitamin E and vitamin C). Linear discriminant analysis and 2-way ANOVA were applied to compare the effects induced by citrus rootstock and ripening stage. The results showed that differences in antioxidant activity and related compounds are mainly dependent on the citrus rootstock, despite ripening stage had also some particular effects. Changes observed in 2012 showed less marked differences among the citrus rootstock. Nevertheless, Cleopatra rootstock showed the highest antioxidant activity in both years, indicating that an increase in its cultivation might be a good solution to sweet orange farmers. Concerning the ripening stage, samples collected in January presented higher vitamin contents, while those collected in April showed higher antioxidant activity. This result allows deciding the harvesting period according to the desired effect. PMID:25462974

  6. Identification of a small protein domain present in all plant lineages that confers high prephenate dehydratase activity.

    PubMed

    El-Azaz, Jorge; de la Torre, Fernando; Ávila, Concepción; Cánovas, Francisco M

    2016-07-01

    l-Phenylalanine serves as a building block for the biosynthesis of proteins, but also as a precursor for a wide range of plant-derived compounds essential for plants and animals. Plants can synthesize Phe within the plastids using arogenate as a precursor; however, an alternative pathway using phenylpyruvate as an intermediate, described for most microorganisms, has recently been proposed. The functionality of this pathway requires the existence of enzymes with prephenate dehydratase (PDT) activity (EC 4.2.1.51) in plants. Using phylogenetic studies, functional complementation assays in yeast and biochemical analysis, we have identified the enzymes displaying PDT activity in Pinus pinaster. Through sequence alignment comparisons and site-directed mutagenesis we have identified a 22-amino acid region conferring PDT activity (PAC domain) and a single Ala314 residue critical to trigger this activity. Our results demonstrate that all plant clades include PAC domain-containing ADTs, suggesting that the PDT activity, and thus the ability to synthesize Phe using phenylpyruvate as an intermediate, has been preserved throughout the evolution of plants. Moreover, this pathway together with the arogenate pathway gives plants a broad and versatile capacity to synthesize Phe and its derived compounds. PAC domain-containing enzymes are also present in green and red algae, and glaucophytes, the three emerging clades following the primary endosymbiont event resulting in the acquisition of plastids in eukaryotes. The evolutionary prokaryotic origin of this domain is discussed. PMID:27125254

  7. Principles of the selection of effective and economic corrosion-resistant alloys in contact with biologically active environments

    SciTech Connect

    Dowling, N.J.E.; Sachs, D.; Bullen, J.A.; White, D.C.

    1993-12-31

    Current field experience with microbiological influenced corrosion (MIC) has now extended into the medium-grade stainless steels containing 4% molybdenum and in excess of 20% chromium. These may indeed be special cases where a combination of synergistic effects, temperature, and wet-dry cycles have aggravated a situation that is already subject to a mild form of MIC. Data are presented from a fresh water field site, comparing the relative performance of several welded coupons, including AISI 304L, 316L, and higher alloyed grades, 622, C276, C-22, 25-6Mo exposed to principally iron-oxidizing bacteria. Specific data is also presented from a saltwater laboratory study of AISI 316/E308 welds where sulfate-reducing bacteria were included. Normally this weld configuration is considered {open_quotes}mismatched{close_quotes} however has nevertheless been employed at several inland power stations. Data is presented which suggested that under {open_quotes}freshwater{close_quotes} conditions (ie. < 150 ppm Cl-) exluding deposits originating from other sources, for example, calcareous scales, an increase in chromium content may significantly reduce the problem. The laboratory study showed that severe generalized rusting of 316/E308 welds may be expected in the presence of fermentative and sulfate-reducing bacteria in chloride environments. The relationship of these data, and of those available in the literature, to the problem of long-term radioactive waste disposal, is discussed with respect to materials selection.

  8. A Research Informed Vision of Good Practice in Multicultural Teacher Education: Design Principles.

    ERIC Educational Resources Information Center

    Zeichner, Kenneth M.; Grant, Carl; Gay, Geneva; Gillette, Maureen; Valli, Linda; Villegas, Ana Maria

    1998-01-01

    Presents 14 design principles that explain good practice in multicultural preservice teacher education. The principles fall under the three main categories of (1) institutional and programmatic principles, (2) personnel principles, and (3) curriculum and instruction principles. (SM)

  9. Impact of the Yakutat indentor corner on present-day tectonics and fault activity in SE Alaska - SW Yukon

    NASA Astrophysics Data System (ADS)

    Mazzotti, S.; Marechal, A.; Ritz, J. F.; Ferry, M. A.

    2015-12-01

    We present an active tectonic model of the SE Alaska - SW Yukon region based principally on the integration of recent GPS velocity data and new fault-slip rates derived from geomorphology. In this region, the Yakutat collision results in complex tectonics with patterns of strain localization and strain partitioning that strongly vary across the various mountain ranges and active faults. We propose that deformation and fault activity in the St. Elias and Chugach Mountains are primarily controlled by the eastern syntaxis of the Yakutat collision, which produces a semi-radial tectonic pattern: Velocities, principal horizontal shortening rates, and maximum horizontal stress orientations rotate by 60 - 80 ° around the syntaxis, from roughly parallel to the relative Pacific - North America motion at the front of the collision to roughly orthogonal southeast of the syntaxis. The interaction between this strain pattern and major inherited tectonic structures inland of the collision zone (i.e., Denali and Duke River Faults) results in various reactivation modes of these structures. Specifically, the Denali Fault shows a very pronounced lateral variations of activity from ~12 mm/a of dextral slip rate in its central section to ~1 mm/a of mostly shortening slip rate along its southern section. This marked change of activity is associated with a possible relay system where the Duke River and Totschunda Faults accommodate a major part (8 - 12 mm/a) of the inland strain transfer directly in front of the syntaxis. This new tectonic model retains some questions, in particular regarding the mechanisms of deformation and strain transfer (1) from the syntaxis to the Duke River - Totschunda system and (2) at the junction between Totschunda and Denali Faults. Numerical models of present-day deformation may help address these issues and provide information about relative strength of the various crustal and inherited fault elements of this system.

  10. Reduction of hexavalent chromium using Aerva lanata L.: elucidation of reduction mechanism and identification of active principles.

    PubMed

    Poonkuzhali, K; Rajeswari, V; Saravanakumar, T; Viswanathamurthi, P; Park, Seung-Moon; Govarthanan, M; Sathishkumar, P; Palvannan, T

    2014-05-15

    The effluent discharge treatment for controlling the environment from non biodegradable metal contaminants using plant extract is an efficient technique. The reduction of hexavalent chromium by abundantly available weed, Aerva lanata L. was investigated using batch equilibrium technique. The variables studied were Cr(VI) concentration, Aerva lanata L. dose, contact time, pH, temperature and agitation speed. Cyclic voltammetry and ICP-MS analysis confirmed the reduction of Cr(VI) to Cr(III). Electrochemical analysis proved that, the chromium has not been degraded and the valency of the chromium has only been changed. ICP-MS analysis shows that 100ng/L of hexavalent chromium was reduced to 97.01ng/L trivalent chromium. These results suggest that components present in the Aerva lanata L. are responsible for the reduction of Cr(VI) to Cr(III). The prime components ferulic acid, kaempherol and β-carboline present in the Aerva lanata L. may be responsible for the reduction of Cr(VI) as evident from LC-MS analysis. PMID:24681590

  11. Adaptive camouflage in the VIS and IR spectral range: main principles and mechanisms

    NASA Astrophysics Data System (ADS)

    Schwarz, Alexander

    2015-10-01

    This paper presents a survey of main applicable technical principles and mechanisms for adaptive camouflage in the visible (VIS) and infrared (IR) spectral ranges. All principles are described by their operation method and technical data such as the active spectral range, the degree and speed of adaptation, weight, power consumption, robustness, usability, lifetime, technology readiness level (TRL) etc.. The paper allows to compare the different principles and to assess them with regard to an application to an adaptive camouflage system.

  12. Software for Fermat's principle and lenses

    NASA Astrophysics Data System (ADS)

    Mihas, Pavlos

    2012-05-01

    Fermat's principle is considered as a unifying concept. It is usually presented erroneously as a 'least time principle'. In this paper we present some software that shows cases of maxima and minima and the application of Fermat's principle to the problem of focusing in lenses.

  13. Software for Fermat's Principle and Lenses

    ERIC Educational Resources Information Center

    Mihas, Pavlos

    2012-01-01

    Fermat's principle is considered as a unifying concept. It is usually presented erroneously as a "least time principle". In this paper we present some software that shows cases of maxima and minima and the application of Fermat's principle to the problem of focusing in lenses. (Contains 12 figures.)

  14. Activation of CO and CO2 on homonuclear boron bonds of fullerene-like BN cages: first principles study

    NASA Astrophysics Data System (ADS)

    Sinthika, S.; Kumar, E. Mathan; Surya, V. J.; Kawazoe, Y.; Park, Noejung; Iyakutti, K.; Thapa, Ranjit

    2015-12-01

    Using density functional theory we investigate the electronic and atomic structure of fullerene-like boron nitride cage structures. The pentagonal ring leads to the formation of homonuclear bonds. The homonuclear bonds are also found in other BN structures having pentagon line defect. The calculated thermodynamics and vibrational spectra indicated that, among various stable configurations of BN-60 cages, the higher number of homonuclear N-N bonds and lower B:N ratio can result in the more stable structure. The homonuclear bonds bestow the system with salient catalytic properties that can be tuned by modifying the B atom bonding environment. We show that homonuclear B-B (B2) bonds can anchor both oxygen and CO molecules making the cage to be potential candidates as catalyst for CO oxidation via Langmuir-Hinshelwood (LH) mechanism. Moreover, the B-B-B (B3) bonds are reactive enough to capture, activate and hydrogenate CO2 molecules to formic acid. The observed trend in reactivity, viz B3 > B2 > B1 is explained in terms of the position of the boron defect state relative to the Fermi level.

  15. Activation of CO and CO2 on homonuclear boron bonds of fullerene-like BN cages: first principles study

    PubMed Central

    Sinthika, S.; Kumar, E. Mathan; Surya, V. J.; Kawazoe, Y.; Park, Noejung; Iyakutti, K.; Thapa, Ranjit

    2015-01-01

    Using density functional theory we investigate the electronic and atomic structure of fullerene-like boron nitride cage structures. The pentagonal ring leads to the formation of homonuclear bonds. The homonuclear bonds are also found in other BN structures having pentagon line defect. The calculated thermodynamics and vibrational spectra indicated that, among various stable configurations of BN-60 cages, the higher number of homonuclear N-N bonds and lower B:N ratio can result in the more stable structure. The homonuclear bonds bestow the system with salient catalytic properties that can be tuned by modifying the B atom bonding environment. We show that homonuclear B-B (B2) bonds can anchor both oxygen and CO molecules making the cage to be potential candidates as catalyst for CO oxidation via Langmuir–Hinshelwood (LH) mechanism. Moreover, the B-B-B (B3) bonds are reactive enough to capture, activate and hydrogenate CO2 molecules to formic acid. The observed trend in reactivity, viz B3 > B2 > B1 is explained in terms of the position of the boron defect state relative to the Fermi level. PMID:26626147

  16. Activation of CO and CO2 on homonuclear boron bonds of fullerene-like BN cages: first principles study.

    PubMed

    Sinthika, S; Kumar, E Mathan; Surya, V J; Kawazoe, Y; Park, Noejung; Iyakutti, K; Thapa, Ranjit

    2015-01-01

    Using density functional theory we investigate the electronic and atomic structure of fullerene-like boron nitride cage structures. The pentagonal ring leads to the formation of homonuclear bonds. The homonuclear bonds are also found in other BN structures having pentagon line defect. The calculated thermodynamics and vibrational spectra indicated that, among various stable configurations of BN-60 cages, the higher number of homonuclear N-N bonds and lower B:N ratio can result in the more stable structure. The homonuclear bonds bestow the system with salient catalytic properties that can be tuned by modifying the B atom bonding environment. We show that homonuclear B-B (B2) bonds can anchor both oxygen and CO molecules making the cage to be potential candidates as catalyst for CO oxidation via Langmuir-Hinshelwood (LH) mechanism. Moreover, the B-B-B (B3) bonds are reactive enough to capture, activate and hydrogenate CO2 molecules to formic acid. The observed trend in reactivity, viz B3 > B2 > B1 is explained in terms of the position of the boron defect state relative to the Fermi level. PMID:26626147

  17. Deletion of Wiskott-Aldrich syndrome protein triggers Rac2 activity and increased cross-presentation by dendritic cells.

    PubMed

    Baptista, Marisa A P; Keszei, Marton; Oliveira, Mariana; Sunahara, Karen K S; Andersson, John; Dahlberg, Carin I M; Worth, Austen J; Liedén, Agne; Kuo, I-Chun; Wallin, Robert P A; Snapper, Scott B; Eidsmo, Liv; Scheynius, Annika; Karlsson, Mikael C I; Bouma, Gerben; Burns, Siobhan O; Forsell, Mattias N E; Thrasher, Adrian J; Nylén, Susanne; Westerberg, Lisa S

    2016-01-01

    Wiskott-Aldrich syndrome (WAS) is caused by loss-of-function mutations in the WASp gene. Decreased cellular responses in WASp-deficient cells have been interpreted to mean that WASp directly regulates these responses in WASp-sufficient cells. Here, we identify an exception to this concept and show that WASp-deficient dendritic cells have increased activation of Rac2 that support cross-presentation to CD8(+) T cells. Using two different skin pathology models, WASp-deficient mice show an accumulation of dendritic cells in the skin and increased expansion of IFNγ-producing CD8(+) T cells in the draining lymph node and spleen. Specific deletion of WASp in dendritic cells leads to marked expansion of CD8(+) T cells at the expense of CD4(+) T cells. WASp-deficient dendritic cells induce increased cross-presentation to CD8(+) T cells by activating Rac2 that maintains a near neutral pH of phagosomes. Our data reveals an intricate balance between activation of WASp and Rac2 signalling pathways in dendritic cells. PMID:27425374

  18. Deletion of Wiskott–Aldrich syndrome protein triggers Rac2 activity and increased cross-presentation by dendritic cells

    PubMed Central

    Baptista, Marisa A. P.; Keszei, Marton; Oliveira, Mariana; Sunahara, Karen K. S.; Andersson, John; Dahlberg, Carin I. M.; Worth, Austen J.; Liedén, Agne; Kuo, I-Chun; Wallin, Robert P. A.; Snapper, Scott B.; Eidsmo, Liv; Scheynius, Annika; Karlsson, Mikael C. I.; Bouma, Gerben; Burns, Siobhan O.; Forsell, Mattias N. E.; Thrasher, Adrian J.; Nylén, Susanne; Westerberg, Lisa S.

    2016-01-01

    Wiskott–Aldrich syndrome (WAS) is caused by loss-of-function mutations in the WASp gene. Decreased cellular responses in WASp-deficient cells have been interpreted to mean that WASp directly regulates these responses in WASp-sufficient cells. Here, we identify an exception to this concept and show that WASp-deficient dendritic cells have increased activation of Rac2 that support cross-presentation to CD8+ T cells. Using two different skin pathology models, WASp-deficient mice show an accumulation of dendritic cells in the skin and increased expansion of IFNγ-producing CD8+ T cells in the draining lymph node and spleen. Specific deletion of WASp in dendritic cells leads to marked expansion of CD8+ T cells at the expense of CD4+ T cells. WASp-deficient dendritic cells induce increased cross-presentation to CD8+ T cells by activating Rac2 that maintains a near neutral pH of phagosomes. Our data reveals an intricate balance between activation of WASp and Rac2 signalling pathways in dendritic cells. PMID:27425374

  19. The doping effect on the catalytic activity of graphene for oxygen evolution reaction in a lithium-air battery: a first-principles study.

    PubMed

    Ren, Xiaodong; Wang, Beizhou; Zhu, Jinzhen; Liu, Jianjun; Zhang, Wenqing; Wen, Zhaoyin

    2015-06-14

    A lithium-air battery as an energy storage technology can be used in electric vehicles due to its large energy density. However, its poor rate capability, low power density and large overpotential problems limit its practical usage. In this paper, the first-principles thermodynamic calculations were performed to study the catalytic activity of X-doped graphene (X = B, N, Al, Si, and P) materials as potential cathodes to enhance charge reactions in a lithium-air battery. Among these materials, P-doped graphene exhibits the highest catalytic activity in reducing the charge voltage by 0.25 V, while B-doped graphene has the highest catalytic activity in decreasing the oxygen evolution barrier by 0.12 eV. By combining these two catalytic effects, B,P-codoped graphene was demonstrated to have an enhanced catalytic activity in reducing the O2 evolution barrier by 0.70 eV and the charge voltage by 0.13 V. B-doped graphene interacts with Li2O2 by Li-sited adsorption in which the electron-withdrawing center can enhance charge transfer from Li2O2 to the substrate, facilitating reduction of O2 evolution barrier. In contrast, X-doped graphene (X = N, Al, Si, and P) prefers O-sited adsorption toward Li2O2, forming a X-O2(2-)···Li(+) interface structure between X-O2(2-) and the rich Li(+) layer. The active structure of X-O2(2-) can weaken the surrounding Li-O2 bonds and significantly reduce Li(+) desorption energy at the interface. Our investigation is helpful in developing a novel catalyst to enhance oxygen evolution reaction (OER) in Li-air batteries. PMID:25970821

  20. Modest Interference with Actin Dynamics in Primary T Cell Activation by Antigen Presenting Cells Preferentially Affects Lamellal Signaling

    PubMed Central

    Roybal, Kole T.; Mace, Emily M.; Clark, Danielle J.; Leard, Alan D.; Herman, Andrew; Verkade, Paul; Orange, Jordan S.; Wülfing, Christoph

    2015-01-01

    Dynamic subcellular distributions of signaling system components are critical regulators of cellular signal transduction through their control of molecular interactions. Understanding how signaling activity depends on such distributions and the cellular structures driving them is required for comprehensive insight into signal transduction. In the activation of primary murine T cells by antigen presenting cells (APC) signaling intermediates associate with various subcellular structures, prominently a transient, wide, and actin-associated lamellum extending from an interdigitated T cell:APC interface several micrometers into the T cell. While actin dynamics are well established as general regulators of cellular organization, their role in controlling signaling organization in primary T cell:APC couples and the specific cellular structures driving it is unresolved. Using modest interference with actin dynamics with a low concentration of Jasplakinolide as corroborated by costimulation blockade we show that T cell actin preferentially controls lamellal signaling localization and activity leading downstream to calcium signaling. Lamellal localization repeatedly related to efficient T cell function. This suggests that the transient lamellal actin matrix regulates T cell signaling associations that facilitate T cell activation. PMID:26237588

  1. Equivalence principles and electromagnetism

    NASA Technical Reports Server (NTRS)

    Ni, W.-T.

    1977-01-01

    The implications of the weak equivalence principles are investigated in detail for electromagnetic systems in a general framework. In particular, it is shown that the universality of free-fall trajectories (Galileo weak equivalence principle) does not imply the validity of the Einstein equivalence principle. However, the Galileo principle plus the universality of free-fall rotation states does imply the Einstein principle.

  2. Principles of Natural Photosynthesis.

    PubMed

    Krewald, Vera; Retegan, Marius; Pantazis, Dimitrios A

    2016-01-01

    Nature relies on a unique and intricate biochemical setup to achieve sunlight-driven water splitting. Combined experimental and computational efforts have produced significant insights into the structural and functional principles governing the operation of the water-oxidizing enzyme Photosystem II in general, and of the oxygen-evolving manganese-calcium cluster at its active site in particular. Here we review the most important aspects of biological water oxidation, emphasizing current knowledge on the organization of the enzyme, the geometric and electronic structure of the catalyst, and the role of calcium and chloride cofactors. The combination of recent experimental work on the identification of possible substrate sites with computational modeling have considerably limited the possible mechanistic pathways for the critical O-O bond formation step. Taken together, the key features and principles of natural photosynthesis may serve as inspiration for the design, development, and implementation of artificial systems. PMID:26099285

  3. Ulcerative Colitis Activity Presenting as Fever of Unknown Origin, in a Patient with Longstanding Disease under Continuous Treatment with Mesalazine

    PubMed Central

    Sfendouraki, Elissavet; Karianos, Theodoros; Saranti, Sofia; Tsitsimelis, Dimitrios; Vrettos, Ioannis; Kalliakmanis, Andreas

    2016-01-01

    Background. The presence of ulcerative colitis (UC) with no bowel symptoms, as fever of unknown origin (FUO), is uncommon. Objective. To describe the case of an 80-year-old woman who presented with fever, with a history of UC under treatment with mesalazine. Case Presentation. She was admitted due to fever lasting for 12 days with no associated symptoms. Seven years earlier, she was diagnosed with UC. After an extended workup for FUO that failed to reach the diagnosis, she underwent a gallium-67 scintigraphy. This revealed a persistent diffuse concentration of gallium-67 in the ascending colon at 24-hour imaging that remained stable at 48- and 72-hour imaging without any topographic change after the use of laxatives. Considering the results and in the absence of another diagnosis, the patient was treated with 30 mg prednisone daily and mesalazine, as treatment of active UC. Subsequently, the patient's condition improved markedly and the fever retreated. One month later, she was reevaluated with a gallium-67 scintigraphy with total absence of gallium-67 concentration in the ascending colon. Conclusion. UC activity must be included in the differential diagnosis of FUO in patients with longstanding disease, since fever may present alone, with no other manifestations. PMID:27504121

  4. Ulcerative Colitis Activity Presenting as Fever of Unknown Origin, in a Patient with Longstanding Disease under Continuous Treatment with Mesalazine.

    PubMed

    Voukelatou, Panagiota; Sfendouraki, Elissavet; Karianos, Theodoros; Saranti, Sofia; Tsitsimelis, Dimitrios; Vrettos, Ioannis; Kalliakmanis, Andreas

    2016-01-01

    Background. The presence of ulcerative colitis (UC) with no bowel symptoms, as fever of unknown origin (FUO), is uncommon. Objective. To describe the case of an 80-year-old woman who presented with fever, with a history of UC under treatment with mesalazine. Case Presentation. She was admitted due to fever lasting for 12 days with no associated symptoms. Seven years earlier, she was diagnosed with UC. After an extended workup for FUO that failed to reach the diagnosis, she underwent a gallium-67 scintigraphy. This revealed a persistent diffuse concentration of gallium-67 in the ascending colon at 24-hour imaging that remained stable at 48- and 72-hour imaging without any topographic change after the use of laxatives. Considering the results and in the absence of another diagnosis, the patient was treated with 30 mg prednisone daily and mesalazine, as treatment of active UC. Subsequently, the patient's condition improved markedly and the fever retreated. One month later, she was reevaluated with a gallium-67 scintigraphy with total absence of gallium-67 concentration in the ascending colon. Conclusion. UC activity must be included in the differential diagnosis of FUO in patients with longstanding disease, since fever may present alone, with no other manifestations. PMID:27504121

  5. Principles of ecosystem sustainability

    SciTech Connect

    Chapin, F.S. III; Torn, M.S.; Tateno, Masaki

    1996-12-01

    Many natural ecosystems are self-sustaining, maintaining an characteristic mosaic of vegetation types of hundreds to thousands of years. In this article we present a new framework for defining the conditions that sustain natural ecosystems and apply these principles to sustainability of managed ecosystems. A sustainable ecosystem is one that, over the normal cycle of disturbance events, maintains its characteristics diversity of major functional groups, productivity, and rates of biogeochemical cycling. These traits are determined by a set of four {open_quotes}interactive controls{close_quotes} (climate, soil resource supply, major functional groups of organisms, and disturbance regime) that both govern and respond to ecosystem processes. Ecosystems cannot be sustained unless the interactive controls oscillate within stable bounds. This occurs when negative feedbacks constrain changes in these controls. For example, negative feedbacks associated with food availability and predation often constrain changes in the population size of a species. Linkages among ecosystems in a landscape can contribute to sustainability by creating or extending the feedback network beyond a single patch. The sustainability of managed systems can be increased by maintaining interactive controls so that they form negative feedbacks within ecosystems and by using laws and regulations to create negative feedbacks between ecosystems and human activities, such as between ocean ecosystems and marine fisheries. Degraded ecosystems can be restored through practices that enhance positive feedbacks to bring the ecosystem to a state where the interactive controls are commensurate with desired ecosystem characteristics. The possible combinations of interactive controls that govern ecosystem traits are limited by the environment, constraining the extent to which ecosystems can be managed sustainably for human purposes. 111 refs., 3 figs., 2 tabs.

  6. Weekly multimodal MRI follow-up of two multiple sclerosis active lesions presenting a transient decrease in ADC

    PubMed Central

    Hannoun, Salem; Roch, Jean-Amédée; Durand-Dubief, Francoise; Vukusic, Sandra; Sappey-Marinier, Dominique; Guttmann, Charles RG; Cotton, Francois

    2015-01-01

    Background and purpose Blood-brain barrier disruption during the earliest phases of lesion formation in multiple sclerosis (MS) patients is commonly ascribed to perivenular inflammatory activity and is usually accompanied by increased diffusivity. Reduced diffusivity has also been shown in active lesions, albeit less frequently. This study aimed to characterize the development and natural history of contrast-enhanced lesions by weekly following five relapsing remitting (RR) MS patients. Materials and methods Diffusion tensor imaging (DTI), perfusion imaging, FLAIR and contrast-enhanced 3D T1-weighted MR, were weekly performed on five untreated patients recently diagnosed with RR MS. Results All five patients showed significant increases of the apparent diffusion coefficient (ADC) in the lesions compared to the first time point. One of the five patients presented 98 active lesions on ADC maps among which 36 had a volume larger than 10 mm3. In two of these lesions, a 1 week transient decrease in ADC was detected at the time of the first gadolinium enhancement. Also, the perfusion analysis showed a concomitant increase in the relative cerebral blood volume. Conclusions The infrequency detection of such ADC decrease in a new lesion is probably due to its very short duration. This observation may be consistent with a hyper-acute inflammatory stage concomitant with an increased reactional perfusion. PMID:25642392

  7. Novel CD47: SIRPα Dependent Mechanism for the Activation of STAT3 in Antigen-Presenting Cell

    PubMed Central

    Toledano, Natan; Gur-Wahnon, Devorah; Ben-Yehuda, Adi; Rachmilewitz, Jacob

    2013-01-01

    Cell surface CD47 interacts with its receptor, signal-regulatory-protein α (SIRPα) that is expressed predominantly on macrophages, to inhibit phagocytosis of normal, healthy cells. This “don’t eat me” signal is mediated through tyrosine phosphorylation of SIRPα at the cytoplasmic ITIM motifs and the recruitment of the phosphatase, SHP-1. We previously revealed a novel mechanism for the activation of the STAT3 pathway and the regulation of human APC maturation and function that is based on cell:cell interaction. In this study, we present evidence supporting the notion that CD47:SIRPα serves as a cell surface receptor: ligand pair involved in this contact-dependent STAT3 activation and regulation of APC maturation. We show that upon co-culturing APC with various primary and tumor cell lines STAT3 phosphorylation and IL-10 expression are induced, and such regulation could be suppressed by specific CD47 siRNAs and shRNAs. Significantly, >50% reduction in CD47 expression abolished the contact-dependent inhibition of T cell activation. Furthermore, co-immunoprecipitation experiments revealed a physical association between SIRPα and STAT3. Thus, we suggest that in addition to signaling through the ITIM-SHP-1 complex that transmit an anti-phagocytotic, CD47:SIRPα also triggers STAT3 signaling that is linked to an immature APC phenotype and peripheral tolerance under steady state and pathological conditions. PMID:24073274

  8. Common Principles and Multiculturalism

    PubMed Central

    Zahedi, Farzaneh; Larijani, Bagher

    2009-01-01

    Judgment on rightness and wrongness of beliefs and behaviors is a main issue in bioethics. Over centuries, big philosophers and ethicists have been discussing the suitable tools to determine which act is morally sound and which one is not. Emerging the contemporary bioethics in the West has resulted in a misconception that absolute westernized principles would be appropriate tools for ethical decision making in different cultures. We will discuss this issue by introducing a clinical case. Considering various cultural beliefs around the world, though it is not logical to consider all of them ethically acceptable, we can gather on some general fundamental principles instead of going to the extremes of relativism and absolutism. Islamic teachings, according to the presented evidence in this paper, fall in with this idea. PMID:23908720

  9. Principles Guiding Vocabulary Learning through Extensive Reading

    ERIC Educational Resources Information Center

    Nation, Paul

    2015-01-01

    Extensive reading is one of a range of activities that can be used in a language learning course. Ideally, the choice of activities to go into a course should be guided by principles which are well supported by research. Similarly, the way each of those activities is used should be guided by well-justified principles. In this article, we look at…

  10. PD-1 on Immature and PD-1 Ligands on Migratory Human Langerhans Cells Regulate Antigen-Presenting Cell Activity

    PubMed Central

    Peña-Cruz, Victor; McDonough, Sean M.; Diaz-Griffero, Felipe; Crum, Christopher P.; Carrasco, Ruben D.; Freeman, Gordon J.

    2010-01-01

    Langerhans cells (LCs) are known as “sentinels” of the immune system that function as professional antigen-presenting cells (APCs) after migration to draining lymph node. LCs are proposed to have a role in tolerance and the resolution of cutaneous immune responses. The Programmed Death-1 (PD-1) receptor and its ligands, PD-L1 and PD-L2, are a co-inhibitory pathway that contributes to the negative regulation of T-lymphocyte activation and peripheral tolerance. Surprisingly, we found PD-1 to be expressed on immature LCs (iLCs) in situ. PD-1 engagement on iLCs reduced IL-6 and macrophage inflammatory protein (MIP)-1α cytokine production in response to TLR2 signals but had no effect on LC maturation. PD-L1 and PD-L2 were expressed at very low levels on iLCs. Maturation of LCs upon migration from epidermis led to loss of PD-l expression and gain of high expression of PD-L1 and PD-L2 as well as co-stimulatory molecules. Blockade of PD-L1 and/or PD-L2 on migratory LCs (mLCs) and DDCs enhanced T-cell activation, as has been reported for other APCs. Thus the PD-1 pathway is active in iLCs and inhibits iLC activities, but expression of receptor and ligands reverses upon maturation and PD-L1 and PD-L2 on mLC function to inhibit T-cell responses. PMID:20445553

  11. Information Presentation

    NASA Technical Reports Server (NTRS)

    Holden, Kritina; Sandor, A.; Thompson, S. G.; McCann, R. S.; Kaiser, M. K.; Begault, D. R.; Adelstein, B. D.; Beutter, B. R.; Stone, L. S.

    2008-01-01

    The goal of the Information Presentation Directed Research Project (DRP) is to address design questions related to the presentation of information to the crew on flight vehicles, surface landers and habitats, and during extra-vehicular activities (EVA). Designers of displays and controls for exploration missions must be prepared to select the text formats, label styles, alarms, electronic procedure designs, and cursor control devices that provide for optimal crew performance on exploration tasks. The major areas of work, or subtasks, within the Information Presentation DRP are: 1) Controls, 2) Displays, 3) Procedures, and 4) EVA Operations.

  12. Cross-presentation of viral antigens in dribbles leads to efficient activation of virus-specific human memory t cells

    PubMed Central

    2014-01-01

    Background Autophagy regulates innate and adaptive immune responses to pathogens and tumors. We have reported that autophagosomes derived from tumor cells after proteasome inhibition, DRibbles (Defective ribosomal products in blebs), were excellent sources of antigens for efficient cross priming of tumor-specific CD8+ T cells, which mediated regression of established tumors in mice. But the activity of DRibbles in human has not been reported. Methods DRibbles or cell lysates derived from HEK293T or UbiLT3 cell lines expressing cytomegalovirus (CMV) pp65 protein or transfected with a plasmid encoding dominant HLA-A2 restricted CMV, Epstein-Barr virus (EBV), and Influenza (Flu) epitopes (CEF) were loaded onto human monocytes or PBMCs and the response of human CMV pp65 or CEF antigen-specific CD4+ and CD8+ memory T cells was detected by intracellular staining. The effect of cytokines (GM-CSF, IL-4, IL-12, TNF-α, IFN-α and IFN-γ) TLR agonists (Lipopolysaccharide, Polyinosinic-polycytidylic acid (poly(I:C), M52-CpG, R848, TLR2 ligand) and CD40 ligand on the cross-presentation of antigens contained in DRibbles or cell lysates was explored. Results In this study we showed that purified monocytes, or human PBMCs, loaded with DRibbles isolated from cells expressing CMV or CEF epitopes, could activate CMV- or CEF-specific memory T cells. DRibbles were significantly more efficient at stimulating CD8+ memory T cells compared to cell lysates expressing the same antigenic epitopes. We optimized the conditions for T-cell activation and IFN-γ production following direct loading of DRibbles onto PBMCs. We found that the addition of Poly(I:C), CD40 ligand, and GM-CSF to the PBMCs together with DRibbles significantly increased the level of CD8+ T cell responses. Conclusions DRibbles containing specific viral antigens are an efficient ex vivo activator of human antigen-specific memory T cells specific for those antigens. This function could be enhanced by combining with Poly

  13. Principles of liquids working in heat engines

    PubMed Central

    Allen, P. C.; Knight, W. R.; Paulson, D. N.; Wheatley, J. C.

    1980-01-01

    The thermodynamic and thermophysical properties of liquids suggest that they should be powerful working fluids in heat engines. Their use requires heat engines based conceptually on the Stirling and Malone principles. The principles are explained, and then experiments on propylene are presented that demonstrate the principles and confirm the thermodynamic analysis. PMID:16592756

  14. Principles of liquids working in heat engines.

    PubMed

    Allen, P C; Knight, W R; Paulson, D N; Wheatley, J C

    1980-01-01

    The thermodynamic and thermophysical properties of liquids suggest that they should be powerful working fluids in heat engines. Their use requires heat engines based conceptually on the Stirling and Malone principles. The principles are explained, and then experiments on propylene are presented that demonstrate the principles and confirm the thermodynamic analysis. PMID:16592756

  15. Principles of Pharmacotherapy: I. Pharmacodynamics

    PubMed Central

    Pallasch, Thomas J.

    1988-01-01

    This paper and the ensuing series present the principles guiding and affecting the ability of drugs to produce therapeutic benefit or untoward harm. The principles of pharmacodynamics and pharmacokinetics, the physiologic basis of adverse drug reactions and suitable antidotal therapy, and the biologic basis of drug allergy, drug-drug interactions, pharmacogenetics, teratology and hematologic reactions to chemicals are explored. These principles serve to guide those administering and using drugs to attain the maximum benefit and least attendant harm from their use. Such is the goal of rational therapeutics. PMID:3046440

  16. Multifunctional Hyaluronic Acid and Chondroitin Sulfate Nanoparticles: Impact of Glycosaminoglycan Presentation on Receptor Mediated Cellular Uptake and Immune Activation.

    PubMed

    Oommen, Oommen P; Duehrkop, Claudia; Nilsson, Bo; Hilborn, Jöns; Varghese, Oommen P

    2016-08-17

    Hyaluronic acid (HA) and chondroitin sulfate (CS) polymers are extensively used for various biomedical applications, such as for tissue engineering, drug delivery, and gene delivery. Although both these biopolymers are known to target cell surface CD44 receptors, their relative cellular targeting properties and immune activation potential have never been evaluated. In this article, we present the synthesis and characterization of novel self-assembled supramolecular HA and CS nanoparticles (NPs). These NPs were developed using fluorescein as a hydrophobic component that induced amphiphilicity in biopolymers and also efficiently stabilized anticancer drug doxorubicin (DOX) promoting a near zero-order drug release. The cellular uptake and cytotoxicity studies of these NPs in different human cancer lines, namely, human colorectal carcinoma cell line HCT116 and human breast cancer cell line MCF-7 demonstrated dose dependent cytotoxicity. Interestingly, both NPs showed CD44 dependent cellular uptake with the CS-DOX NP displaying higher dose-dependent cytotoxicity than the HA-DOX NP in different mammalian cells tested. Immunological evaluation of these nanocarriers in an ex vivo human whole blood model revealed that unlike unmodified polymers, the HA NP and CS NP surprisingly showed platelet aggregation and thrombin-antithrombin complex formation at high concentrations (0.8 mg/mL). We also observed a clear difference in early- and late-stage complement activation (C3a and sC5b-9) with CS and CS NP triggering significant complement activation at high concentrations (0.08-0.8 mg/mL), unlike HA and HA NP. These results offer new insight into designing glycosaminoglycan-based NPs and understanding their hematological responses and targeting ability. PMID:27468113

  17. Mitochondrial H2O2 in Lung Antigen-Presenting Cells Blocks NF-κB Activation to Prevent Unwarranted Immune Activation.

    PubMed

    Khare, Anupriya; Raundhal, Mahesh; Chakraborty, Krishnendu; Das, Sudipta; Corey, Catherine; Kamga, Christelle K; Quesnelle, Kelly; St Croix, Claudette; Watkins, Simon C; Morse, Christina; Oriss, Timothy B; Huff, Rachael; Hannum, Rachel; Ray, Prabir; Shiva, Sruti; Ray, Anuradha

    2016-05-24

    Inhalation of environmental antigens such as allergens does not always induce inflammation in the respiratory tract. While antigen-presenting cells (APCs), including dendritic cells and macrophages, take up inhaled antigens, the cell-intrinsic molecular mechanisms that prevent an inflammatory response during this process, such as activation of the transcription factor NF-κB, are not well understood. Here, we show that the nuclear receptor PPARγ plays a critical role in blocking NF-κB activation in response to inhaled antigens to preserve immune tolerance. Tolerance induction promoted mitochondrial respiration, generation of H2O2, and suppression of NF-κB activation in WT, but not PPARγ-deficient, APCs. Forced restoration of H2O2 in PPARγ-deficient cells suppressed IκBα degradation and NF-κB activation. Conversely, scavenging reactive oxygen species from mitochondria promoted IκBα degradation with loss of regulatory and promotion of inflammatory T cell responses in vivo. Thus, communication between PPARγ and the mitochondria maintains immune quiescence in the airways. PMID:27184852

  18. Identification of subjects for social responsibility education at universities and the present activity at the university of Tokyo.

    PubMed

    Karima, Risuke; Oshima, Yoshito; Yamamoto, Kazuo

    2006-01-01

    The management of corporate social responsibility (CSR) has recently become a critical concern for companies in advanced countries. For universities, there is a requirement to contribute to the promotion of CSR, resulting in graduates who have sufficient cognition of and a good attitude towards CSR. In addition, universities have social responsibilities, which can be called "University Social Responsibility (USR)." On the basis of the concepts of the guidelines for CSR in the "Green Paper," which was presented by the European Committee (EC) in 2001, we provide a perspective here on what factors dictate the establishment of education programs for social responsibilities at universities. These factors include an outline of the concepts and the significance of CSR, social ethics and the morals of higher education and research, compliances, human resource management, human rights, safety and health in academic settings, and various concerns regarding environmental safety and preservation. Additionally, through the concept postulated here for social responsible education, in this paper, we introduce the present activity at the University of Tokyo (UT) in terms of the education program for CSR and USR, proposing that the future establishment of university-wide education programs based on the concept of CSR and the value of sustainability is required at UT. PMID:17273148

  19. Conductive Education and the Educational Principles of the Peto System.

    ERIC Educational Resources Information Center

    Szolnoki, John F.

    1994-01-01

    The educational principles of the Peto system of conductive education for students with motor disabilities are presented. A "conductor" undertakes the process of upbringing and education simultaneously. Learning begins with a sequential task analysis of daily activities, initially started with conscious, rhythmical intention and the mobilization…

  20. Transformational Teaching: Theoretical Underpinnings, Basic Principles, and Core Methods

    ERIC Educational Resources Information Center

    Slavich, George M.; Zimbardo, Philip G.

    2012-01-01

    Approaches to classroom instruction have evolved considerably over the past 50 years. This progress has been spurred by the development of several learning principles and methods of instruction, including active learning, student-centered learning, collaborative learning, experiential learning, and problem-based learning. In the present paper, we…

  1. Recombinase Activating Gene 1 Deficiencies Without Omenn Syndrome May Also Present With Eosinophilia and Bone Marrow Fibrosis

    PubMed Central

    Ulusoy, Ezgi; Karaca, Neslihan Edeer; Azarsiz, Elif; Berdeli, Afig; Aksu, Guzide; Kutukculer, Necil

    2016-01-01

    Background Severe combined immunodeficiency (SCID) syndromes are a heterogenous group of diseases characterized by impairment in both cellular and humoral immunity with a range of genetic disorders. Complete recombinase activating gene (RAG) deficiency is associated with classical T-B-NK+ SCID which is the most common phenotype of Turkish SCID patients. There is a broad spectrum of hypomorfic RAG mutations including Omenn syndrome, leaky or atypical SCID with expansion of γδ T cells, autoimmunity and cytomegalovirus (CMV) infections. Methods Twenty-one (44%) patients had RAG1 deficiency of all 44 SCID patients followed up by pediatric immunology department. A retrospective analysis was conducted on the medical records of all SCID patients with RAG1 deficiency. Results Eight patients were classified as T-B-NK+ SCID, five patients as T+B-NK+ SCID (three of these were Omenn phenotype), and eight patients as T+B+NK+ SCID phenotype. Mean age of the whole study group, mean age at onset of symptoms and mean age at diagnosis were 87.7 ± 73.8 (12 - 256), 4.4 ± 8.2 (1 - 36) and 29.1 ± 56.8 (1 - 244) months, respectively. Consanguinity was present in 11 (52%) of 21 patients. Autoimmunity was found in six patients (28%). Ten patients (47%) had CMV infection, four (19%) had Epstein-Barr virus (EBV) infections and three (14%) had Bacillus Calmette-Guerin (BCG) infections. Seven patients who had refractory cytopenia (two pancytopenia and five bicytopenia) underwent bone marrow biopsy, three of whom had bone marrow fibrosis. Future evaluations must be considered about bone marrow fibrosis in RAG1 deficiency patients. Eosinophilia was observed in 10 patients, seven of whom did not have Omenn phenotype. Conclusion Non-Omenn phenotype RAG1 deficiencies can also present with eosinophilia. This report is presented to emphasize that RAG1 mutations may lead to diverse clinical phenotypes. PMID:27081423

  2. Proof of principle in a de novo designed protein maquette: an allosterically regulated, charge-activated conformational switch in a tetra-alpha-helix bundle.

    PubMed

    Grosset, A M; Gibney, B R; Rabanal, F; Moser, C C; Dutton, P L

    2001-05-01

    New understanding of the engineering and allosteric regulation of natural protein conformational switches (such as those that couple chemical and ionic signals, mechanical force, and electro/chemical free energy for biochemical activation, catalysis, and motion) can be derived from simple de novo designed synthetic protein models (maquettes). We demonstrate proof of principle of both reversible switch action and allosteric regulation in a tetra-alpha-helical bundle protein composed of two identical di-helical subunits containing heme coordinated at a specific position close to the disulfide loop region. Individual bundles assume one of two switch states related by large-scale mechanical changes: a syn-topology (helices of the different subunits parallel) or anti-topology (helices antiparallel). Both the spectral properties of a coproporphyrin probe appended to the loop region and the distance-dependent redox interaction between the hemes identify the topologies. Beginning from a syn-topology, introduction of ferric heme in each subunit (either binding or redox change) shifts the topological balance by 25-50-fold (1.9-2.3 kcal/mol) to an anti-dominance. Charge repulsion between the two internal cationic ferric hemes drives the syn- to anti-switch, as demonstrated in two ways. When fixed in the syn-topology, the second ferric heme binding is 25-80-fold (1.9-2.6 kcal/mol) weaker than the first, and adjacent heme redox potentials are split by 80 mV (1.85 kcal/mol), values that energetically match the shift in topological balance. Allosteric and cooperative regulation of the switch by ionic strength exploits the shielded charge interactions between the two hemes and the exposed, cooperative interactions between the coproporphyrin carboxylates. PMID:11331012

  3. Soft X-ray variability over the present minimum of solar activity as observed by SphinX

    NASA Astrophysics Data System (ADS)

    Gburek, S.; Siarkowski, M.; Kepa, A.; Sylwester, J.; Kowalinski, M.; Bakala, J.; Podgorski, P.; Kordylewski, Z.; Plocieniak, S.; Sylwester, B.; Trzebinski, W.; Kuzin, S.

    2011-04-01

    Solar Photometer in X-rays (SphinX) is an instrument designed to observe the Sun in X-rays in the energy range 0.85-15.00 keV. SphinX is incorporated within the Russian TESIS X and EUV telescope complex aboard the CORONAS-Photon satellite which was launched on January 30, 2009 at 13:30 UT from the Plesetsk Cosmodrome, northern Russia. Since February, 2009 SphinX has been measuring solar X-ray radiation nearly continuously. The principle of SphinX operation and the content of the instrument data archives is studied. Issues related to dissemination of SphinX calibration, data, repository mirrors locations, types of data and metadata are discussed. Variability of soft X-ray solar flux is studied using data collected by SphinX over entire mission duration.

  4. Activated Conventional T-Cells Are Present in Langerhans Cell Histiocytosis Lesions Despite the Presence of Immune Suppressive Cytokines.

    PubMed

    Quispel, Willemijn T; Stegehuis-Kamp, Janine A; Santos, Susy J; Egeler, R Maarten; van Halteren, Astrid G S

    2015-10-01

    Langerhans cell histiocytosis (LCH) lesions are characterized by neoplastic CD1a(+)/Langerin(+) histiocytes (LCH-cells) and display many features of chronic inflammation. Cancer cells can escape immune-surveillance through intra-tumoral secretion of immune-suppressive cytokines. We therefore studied by immunohistochemistry the local cytokine milieu and phenotypic characteristics of T-cells and LCH-cells present in LCH lesions collected from 25 therapy naïve patients. LCH biopsies predominantly expressed interleukin-10 (IL-10) (10/25), transforming growth factor-beta (TGF-β) (9/25), or both cytokines (6/25). The absolute number of CD3(+)T-cells and the CD3(+)FOXP3(-) conventional cell (T-CONV) versus the CD3(+)FOXP3(+) regulatory T-cell (T-REG) was comparable for each suppressive cytokine profile (5:1). IL-10-expressing lesions contained, however, a higher proportion of T-CONV expressing the activation markers CD25 98% (38%-100%) and inducible costimulatory molecule (ICOS) 86% (47%-100%) than lesions wherein solely TGF-β was detected (CD25(+) 20% (6%-54%); ICOS(+) 29% (7%-51%)). Virtually all T-REG expressed CD25 and ICOS in IL-10 lesions, whereas TGF-β(+) lesions contained a lower proportion of ICOS(+) T-REG (P=0.05). IL-10(+) lesions contained more LCH-cells expressing high intensity of ICOS ligand (ICOSL) compared with TGF-β(+) lesions (P=0.03). ICOS expression by lesion-infiltrating T-CONV and T-REG positively correlated to the extent of ICOSL expression by LCH-cells (P=0.004). Our study points out that the combined detection of interlesional IL-10 and ICOSL expression by LCH-cells is associated with the highest prevalence of activated T-CONV. Immune profiling of LCH-affected tissues obtained at the time of diagnosis may set the stage for the development of new types of therapies, which aim at local boosting of immune cells that recognize and eliminate neoplastic LCH-cells. PMID:26381039

  5. Characterization and photocatalytic activity of Fe- and N-co-deposited TiO{sub 2} and first-principles study for electronic structure

    SciTech Connect

    Yen, Chung-Chih; Wang, Da-Yung; Chang, Li-Shin; Shih, Han C.

    2011-08-15

    Titanium dioxide (TiO{sub 2}), co-deposited with Fe and N, is first implanted with Fe by a metal plasma ion implantation (MPII) process and then annealed in N{sub 2} atmosphere at a temperature regime of 400-600 deg. C. First-principle calculations show that the (Fe, N) co-deposited TiO{sub 2} films produced additional band gap levels at the bottom of the conduction band (CB) and on the top of the valence band (VB). The (Fe, N) co-deposited TiO{sub 2} films were effective in both prohibiting electron-hole recombination and generating additional Fe-O and N-Ti-O impurity levels for the TiO{sub 2} band gap. The (Fe, N) co-deposited TiO{sub 2} has a narrower band gap of 1.97 eV than Fe-implanted TiO{sub 2} (3.14 eV) and N-doped TiO{sub 2} (2.16 eV). A significant reduction of TiO{sub 2} band gap energy from 3.22 to 1.97 eV was achieved, which resulted in the extension of photocatalytic activity of TiO{sub 2} from UV to Vis regime. The photocatalytic activity and removal rate were approximately two-fold higher than that of the Fe-implanted TiO{sub 2} under visible light irradiation. - Graphical abstract: The electronic properties of (Fe, N) co-deposited TiO{sub 2} films determined by theoretical calculations is graphically shown; Fe and N preferentially substitute the Ti and O site, to form impurity level. Highlights: > The MPII produces a simple and low cost process for the fabrication of visible light photocatalysts. > Both theoretical and experimental approaches are used to discuss the relationship between band structure and photocatalysis. > The Fe and N preferentially substitute the Ti and O site, which generate additional Fe-O and N-Ti-O impurity levels for the TiO{sub 2} band gap. > A significant reduction of TiO{sub 2} band gap energy from 3.22 to 1.97 eV was achieved.

  6. Last Glacial - Present Glacial Activity in East Greenland Fjords Inferred from Swath Bathymetry and High-Resolution Seismic Data

    NASA Astrophysics Data System (ADS)

    Forwick, M.; Laberg, J. S.; Husum, K.; Olsen, I. L.

    2014-12-01

    Swath bathymetry and high-resolution penetration echo sounder (chirp) data from fjords and sounds between Kong Oscars Fjord and Bredefjord, East Greenland, reveal glacial landforms and sedimentary processes that can be used to infer glacial activity from the last glacial to the present. Relatively straight, linear features oriented parallel to the fjord axes, as well as beyond the mouths of some fjords, are interpreted to be glacial lineations providing evidence of fast-flowing grounded ice draining the eastern parts of the Greenland Ice Sheet during the last glacial. In some areas, the glacial lineations are the only preserved glacigenic landfjorms (e.g. beyond the mouth of Bredefjord). However, in other areas, they are covered with multiple transverse ridges interpreted to be small terminal moraines (e.g. in Youngsund). Whereas the absence of such moraines is suggested to represent a rapid ice retreat due to lift-up and disintegration during parts of the deglaciation, their presence reflects that multiple halts and/or re-advances interrupted the retreat. Acoustically stratified sediment sequences dominate the fjord-fill stratigraphies (up to 180 ms two-way travel time). These deposits are suggested to reflect repeatedly changing lithological compositions in a glacimarine environment where deposition mainly occurred from suspension fall-out, in addition to ice rafting from icebergs calving off from tidewater glaciers, and sea ice. The stratified deposits form often relatively uniform drapes indicating that the tidewater glaciers were mainly located near the fjord heads since the last deglaciation. However, acoustically transparent bodies with irregular geometries, intercalated within the stratified deposits, occur in some of the inner fjords. These are suggested to be glacigenic sediment wedges (debris-flow lobes) that formed during relatively recent advances of tidewater glaciers (e.g. in Nordfjord and Moskusoksefjord).

  7. In vitro chemo-preventive activities of hydroxytyrosol: the main phenolic compound present in extra-virgin olive oil.

    PubMed

    Rosignoli, Patrizia; Fuccelli, Raffaela; Sepporta, Maria Vittoria; Fabiani, Roberto

    2016-01-01

    The co-incubation in the culture medium with hydroxytyrosol [3,4-dihydroxyphenyl ethanol (3,4-DHPEA)], the main phenolic compound present in extra-virgin olive oil, and H2O2 reduces the oxidative DNA damage in peripheral blood mononuclear cells (PBMC). In this study we investigate, by the comet assay, the ability of 3,4-DHPEA to inhibit the H2O2 induced DNA damage when pre-incubated with PBMC and then removed before the exposure of cells to H2O2. Low doses of 3,4-DHPEA (10-100 μM) pre-incubated for 30 min with PBMC reduced the DNA damage induced by the treatment with H2O2 200 μM for 5 min at 4 °C. Prolonging the exposure time up to 6 h completely prevented the DNA damage. Furthermore we extensively analysed, by the MTT assay, the anti-proliferative activities of 3,4-DHPEA on breast (MDA and MCF-7), prostate (LNCap and PC3) and colon (SW480 and HCT116) cancer cell lines and correlated these effects with the H2O2 accumulation. The concentration of H2O2 in the culture medium was measured by the ferrous ion oxidation-xylenol orange method. The proliferation of all the cell lines was inhibited but at different levels: the prostate cancer cells were more resistant to the growth inhibition with respect to breast and colon cancer cells. The ability of the different cell lines to remove H2O2 from the culture medium was inversely correlated with their sensitivity to the anti-proliferative effect of 3,4-DHPEA. Therefore, 3,4-DHPEA may act as a chemopreventive agent acting on both initiation and promotion/progression phases of carcinogenesis. PMID:26469183

  8. Principles of Safety Pharmacology

    PubMed Central

    Pugsley, M K; Authier, S; Curtis, M J

    2008-01-01

    Safety Pharmacology is a rapidly developing discipline that uses the basic principles of pharmacology in a regulatory-driven process to generate data to inform risk/benefit assessment. The aim of Safety Pharmacology is to characterize the pharmacodynamic/pharmacokinetic (PK/PD) relationship of a drug's adverse effects using continuously evolving methodology. Unlike toxicology, Safety Pharmacology includes within its remit a regulatory requirement to predict the risk of rare lethal events. This gives Safety Pharmacology its unique character. The key issues for Safety Pharmacology are detection of an adverse effect liability, projection of the data into safety margin calculation and finally clinical safety monitoring. This article sets out to explain the drivers for Safety Pharmacology so that the wider pharmacology community is better placed to understand the discipline. It concludes with a summary of principles that may help inform future resolution of unmet needs (especially establishing model validation for accurate risk assessment). Subsequent articles in this issue of the journal address specific aspects of Safety Pharmacology to explore the issues of model choice, the burden of proof and to highlight areas of intensive activity (such as testing for drug-induced rare event liability, and the challenge of testing the safety of so-called biologics (antibodies, gene therapy and so on.). PMID:18604233

  9. Chemical Principls Exemplified

    ERIC Educational Resources Information Center

    Plumb, Robert C.

    1973-01-01

    Two topics are discussed: (1) Stomach Upset Caused by Aspirin, illustrating principles of acid-base equilibrium and solubility; (2) Physical Chemistry of the Drinking Duck, illustrating principles of phase equilibria and thermodynamics. (DF)

  10. Principles of Induction Accelerators

    NASA Astrophysics Data System (ADS)

    Briggs*, Richard J.

    The basic concepts involved in induction accelerators are introduced in this chapter. The objective is to provide a foundation for the more detailed coverage of key technology elements and specific applications in the following chapters. A wide variety of induction accelerators are discussed in the following chapters, from the high current linear electron accelerator configurations that have been the main focus of the original developments, to circular configurations like the ion synchrotrons that are the subject of more recent research. The main focus in the present chapter is on the induction module containing the magnetic core that plays the role of a transformer in coupling the pulsed power from the modulator to the charged particle beam. This is the essential common element in all these induction accelerators, and an understanding of the basic processes involved in its operation is the main objective of this chapter. (See [1] for a useful and complementary presentation of the basic principles in induction linacs.)

  11. Student Perceptions of Value Added in an Active Learning Experience: Producing, Reviewing and Evaluating a Sales Team Video Presentation

    ERIC Educational Resources Information Center

    Corbett, James J.; Kezim, Boualem; Stewart, James

    2010-01-01

    This study investigates the effectiveness of a video team-based activity as a learning experience in a sales management course. Students perceived this learning activity approach as a beneficial and effective instructional technique. The benefits of making a video in a marketing course reinforce the understanding and the use of the sales process…

  12. Minimum Principles in Motor Control.

    PubMed

    Engelbrecht, Sascha E.

    2001-06-01

    Minimum (or minimal) principles are mathematical laws that were first used in physics: Hamilton's principle and Fermat's principle of least time are two famous example. In the past decade, a number of motor control theories have been proposed that are formally of the same kind as the minimum principles of physics, and some of these have been quite successful at predicting motor performance in a variety of tasks. The present paper provides a comprehensive review of this work. Particular attention is given to the relation between minimum theories in motor control and those used in other disciplines. Other issues around which the review is organized include: (1) the relation between minimum principles and structural models of motor planning and motor control, (2) the empirically-driven development of minimum principles and the danger of circular theorizing, and (3) the design of critical tests for minimum theories. Some perspectives for future research are discussed in the concluding section of the paper. Copyright 2001 Academic Press. PMID:11401453

  13. Principles of Modern Soccer.

    ERIC Educational Resources Information Center

    Beim, George

    This book is written to give a better understanding of the principles of modern soccer to coaches and players. In nine chapters the following elements of the game are covered: (1) the development of systems; (2) the principles of attack; (3) the principles of defense; (4) training games; (5) strategies employed in restarts; (6) physical fitness…

  14. Chemical Principles Exemplified

    ERIC Educational Resources Information Center

    Plumb, Robert C.

    1970-01-01

    This is the first of a new series of brief ancedotes about materials and phenomena which exemplify chemical principles. Examples include (1) the sea-lab experiment illustrating principles of the kinetic theory of gases, (2) snow-making machines illustrating principles of thermodynamics in gas expansions and phase changes, and (3) sunglasses that…

  15. Characterization of the novel protein kinase activity present in the R1 subunit of herpes simplex virus ribonucleotide reductase.

    PubMed Central

    Cooper, J; Conner, J; Clements, J B

    1995-01-01

    We have compared the protein kinase activities of the R1 subunits from herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) ribonucleotide reductase following expression in Escherichia coli. Autophosphorylation activity was observed when kinase assays were performed with immunoprecipitated R1 or proteins purified to homogeneity, and the activity was stimulated by the basic protein protamine. Transphosphorylation of histones or calmodulin by purified or immunoprecipitated HSV-1 and HSV-2 R1 was not observed, and our results suggest that the activities of these two proteins are similar. We further characterized the protein kinase activity of HSV-1 R1 by producing insertion and deletion mutants constructed with a plasmid expressing R1 amino acids 1 to 449. C-terminal deletion analysis identified the catalytic core of the enzyme as comprising residues 1 to 292, and this polypeptide will be useful for structural determinations by X-ray crystallography. Insertion of a 4-amino-acid sequence at sites within the protein kinase domain identified regions essential for activity; insertions at residues 22 and 112 completely inactivated activity, and an insertion at residue 136 reduced activity sixfold. Similar insertions at residues 257, 262, 292, and 343 had no effect on activity. The ATP analog 5'-fluorosulfonylbenzoyladenosine, which covalently modifies conventional eukaryotic kinases at an essential lysine residue within the active site, did label HSV R1, but this labelling occurred outside the N-terminal domain. These data indicate that the HSV R1 kinase is novel and distinct from other eukaryotic protein kinases. PMID:7609068

  16. System level electrochemical principles

    NASA Technical Reports Server (NTRS)

    Thaller, L. H.

    1985-01-01

    The traditional electrochemical storage concepts are difficult to translate into high power, high voltage multikilowatt storage systems. The increased use of electronics, and the use of electrochemical couples that minimize the difficulties associated with the corrective measures to reduce the cell to cell capacity dispersion were adopted by battery technology. Actively cooled bipolar concepts are described which represent some attractive alternative system concepts. They are projected to have higher energy densities lower volumes than current concepts. They should be easier to scale from one capacity to another and have a closer cell to cell capacity balance. These newer storage system concepts are easier to manage since they are designed to be a fully integrated battery. These ideas are referred to as system level electrochemistry. The hydrogen-oxygen regenerative fuel cells (RFC) is probably the best example of the integrated use of these principles.

  17. Fracture mechanics principles.

    PubMed

    Mecholsky, J J

    1995-03-01

    The principles of linear elastic fracture mechanics (LEFM) were developed in the 1950s by George Irwin (1957). This work was based on previous investigations of Griffith (1920) and Orowan (1944). Irwin (1957) demonstrated that a crack shape in a particular location with respect to the loading geometry had a stress intensity associated with it. He also demonstrated the equivalence between the stress intensity concept and the familiar Griffith criterion of failure. More importantly, he described the systematic and controlled evaluation of the toughness of a material. Toughness is defined as the resistance of a material to rapid crack propagation and can be characterized by one parameter, Kic. In contrast, the strength of a material is dependent on the size of the initiating crack present in that particular sample or component. The fracture toughness of a material is generally independent of the size of the initiating crack. The strength of any product is limited by the size of the cracks or defects during processing, production and handling. Thus, the application of fracture mechanics principles to dental biomaterials is invaluable in new material development, production control and failure analysis. This paper describes the most useful equations of fracture mechanics to be used in the failure analysis of dental biomaterials. PMID:8621030

  18. Revisiting Tversky's diagnosticity principle.

    PubMed

    Evers, Ellen R K; Lakens, Daniël

    2014-01-01

    Similarity is a fundamental concept in cognition. In 1977, Amos Tversky published a highly influential feature-based model of how people judge the similarity between objects. The model highlights the context-dependence of similarity judgments, and challenged geometric models of similarity. One of the context-dependent effects Tversky describes is the diagnosticity principle. The diagnosticity principle determines which features are used to cluster multiple objects into subgroups. Perceived similarity between items within clusters is expected to increase, while similarity between items in different clusters decreases. Here, we present two pre-registered replications of the studies on the diagnosticity effect reported in Tversky (1977). Additionally, one alternative mechanism that has been proposed to play a role in the original studies, an increase in the choice for distractor items (a substitution effect, see Medin et al., 1995), is examined. Our results replicate those found by Tversky (1977), revealing an average diagnosticity-effect of 4.75%. However, when we eliminate the possibility of substitution effects confounding the results, a meta-analysis of the data provides no indication of any remaining effect of diagnosticity. PMID:25161638

  19. Revisiting Tversky's diagnosticity principle

    PubMed Central

    Evers, Ellen R. K.; Lakens, Daniël

    2013-01-01

    Similarity is a fundamental concept in cognition. In 1977, Amos Tversky published a highly influential feature-based model of how people judge the similarity between objects. The model highlights the context-dependence of similarity judgments, and challenged geometric models of similarity. One of the context-dependent effects Tversky describes is the diagnosticity principle. The diagnosticity principle determines which features are used to cluster multiple objects into subgroups. Perceived similarity between items within clusters is expected to increase, while similarity between items in different clusters decreases. Here, we present two pre-registered replications of the studies on the diagnosticity effect reported in Tversky (1977). Additionally, one alternative mechanism that has been proposed to play a role in the original studies, an increase in the choice for distractor items (a substitution effect, see Medin et al., 1995), is examined. Our results replicate those found by Tversky (1977), revealing an average diagnosticity-effect of 4.75%. However, when we eliminate the possibility of substitution effects confounding the results, a meta-analysis of the data provides no indication of any remaining effect of diagnosticity. PMID:25161638

  20. RPL Dosimetry: Principles and Applications

    SciTech Connect

    Yamamoto, Takayoshi

    2011-05-05

    The principle of radio-photoluminescence (RPL) is applied to the glass dosimeter, which is one of the most excellent solid state dosimeters. The silver activated phosphate glass irradiated with ionizing radiations emits luminescence when exposed to UV light. This phenomenon is called RPL. The most characteristic features of the glass dosimeters are data accumulation and no fading. The basic principle of RPL is described and then how it is applied to the glass dosimeter is explained. Finally some applications of RPL will be introduced.

  1. Short Communication: Immune Activation Is Present in HIV-1-Exposed Seronegative Individuals and Is Independent of Microbial Translocation.

    PubMed

    Saulle, Irma; Biasin, Mara; Gnudi, Federica; Rainone, Veronica; Ibba, Salomè Valentina; Caputo, Sergio Lo; Mazzotta, Francesco; Trabattoni, Daria; Clerici, Mario

    2016-02-01

    Analyses of immune activation in HIV-exposed seronegative individuals (HESN) yielded discrepant results. To clarify this issue we performed an extensive investigation of immune parameters in HESN and, in particular, we analyzed in these individuals the possible presence of microbial translocation, the most widely accepted reason driving immune activation in HIV-infected patients. Results showed that immune activation, a skewing of T lymphocyte maturation, and increased responsiveness to lipopolysaccharide (LPS) characterize the HESN phenotype; this is not driven by alterations of the gastrointestinal barrier and microbial translocation. The activation state seen in HESN may influence the induction of stronger adaptive antiviral immune responses and may represent a virus exposure-induced innate immune protective phenotype against HIV. PMID:26414485

  2. Effect of Trisetum flavescens P.B. on calcium and phosphorus metabolism in rats. Experimental evidence for the principle actively affecting phospho-calcium homeostasis.

    PubMed

    Wilczek, H; Ston, J; Pacovský, V

    1978-01-01

    After reviewing the literature on the vitamin D3-like activity of certain plants [Solanum malacoxylon, Cestrum diurnum and Trisetum flavescens], the authors present results of experiments in which dried Trisetum flavescens was administered perorally to rats. The addition of 2.5% dried Trisetum flavescens to the standard laboratory diet caused a drop in blood phosphate levels and a simultaneous marked increase in the calcium and phosphorus content of bones of the experimental animals. The mechanism of the action of Trisetum flavescens on phosphocalcium metabolism is discussed. PMID:150612

  3. Present-day submarine hydrothermal activity in the Taupo-Rotorua Zone (Bay of Plenty, New Zealand)

    SciTech Connect

    Osipenko, A.B.; Egorov, Yu.O.; Fazlullin, S.M.; Gavrilenko, G.M.; Shul`kin, V.I.; Chertkova, L.V.

    1994-09-01

    We made detailed descriptions of the structure and material composition of sedimentary and water columns in the vicinity of active submarine hydrothermal activity in the southern part of the Bay of Plenty (North Island, New Zealand). Geophysical methods revealed that the hydrothermal system is confined to a tectonically distinct zone with a sedimentary cover characterized by complex structure. Chemical and mineralogical investigations confirmed that the activity of underwater vents exerts no substantial regional influence on the composition and features of ore mineralization in these formations. It is shown that essentially hydrothermal formations distinguishable within areas of otherwise monotypic sediments directly coincide with zones of hydrothermal discharge in the ocean floor. The absence of pronounced hydrothermal anomalies, together with the presence of {open_quotes}tongues{close_quotes} of anomalous concentrations of water-soluble gases suggests that the discharges are primarily hydrothermal in character.

  4. Neuronavigation. Principles. Surgical technique.

    PubMed

    Ivanov, Marcel; Ciurea, Alexandru Vlad

    2009-01-01

    Neuronavigation and stereotaxy are techniques designed to help neurosurgeons precisely localize different intracerebral pathological processes by using a set of preoperative images (CT, MRI, fMRI, PET, SPECT etc.). The development of computer assisted surgery was possible only after a significant technological progress, especially in the area of informatics and imagistics. The main indications of neuronavigation are represented by the targeting of small and deep intracerebral lesions and choosing the best way to treat them, in order to preserve the neurological function. Stereotaxis also allows lesioning or stimulation of basal ganglia for the treatment of movement disorders. These techniques can bring an important amount of confort both to the patient and to the neurosurgeon. Neuronavigation was introduced in Romania around 2003, in four neurosurgical centers. We present our five-years experience in neuronavigation and describe the main principles and surgical techniques. PMID:20108488

  5. Increased Interest in Physiology and Science among Adolescents after Presentations and Activities Administered by Undergraduate Physiology Students

    ERIC Educational Resources Information Center

    da Silva de Vargas, Liane; Rosa de Menezes, Jefferson; Billig Mello-Carpes, Pâmela

    2016-01-01

    In this article, the authors describe a set of activities performed in south Brazil that are aligned with the objectives of PhUn Week and promote the integration between universities and public schools and the dissemination of knowledge of physiology. To achieve this goal, the authors adopted a program in which undergraduate physiology students…

  6. PREDICTING THE ADSORPTION CAPACITY OF ACTIVATED CARBON FOR EMERGING ORGANIC CONTAMINANTS FROM FUNDAMENTAL ADSORBENT AND ADSORBATE PROPERTIES - PRESENTATION

    EPA Science Inventory

    A quantitative structure-property relationship (QSPR) was developed and combined with the Polanyi-Dubinin-Manes model to predict adsorption isotherms of emerging contaminants on activated carbons with a wide range of physico-chemical properties. Affinity coefficients (βl

  7. Effects of Different Multimedia Presentations on Viewers' Information-Processing Activities Measured by Eye-Tracking Technology

    ERIC Educational Resources Information Center

    Chuang, Hsueh-Hua; Liu, Han-Chin

    2012-01-01

    This study implemented eye-tracking technology to understand the impact of different multimedia instructional materials, i.e., five successive pages versus a single page with the same amount of information, on information-processing activities in 21 non-science-major college students. The findings showed that students demonstrated the same number…

  8. Activation and inhibition of thermosensitive TRP channels by voacangine, an alkaloid present in Voacanga africana, an African tree.

    PubMed

    Terada, Yuko; Horie, Syunji; Takayama, Hiromitsu; Uchida, Kunitoshi; Tominaga, Makoto; Watanabe, Tatsuo

    2014-02-28

    Voacangine (1) is an alkaloid found in the root bark of Voacanga africana. Our previous work has suggested that 1 is a novel transient receptor potential vanilloid type 1 (TRPV1) antagonist. In this study, the agonist and antagonist activities of 1 were examined against thermosensitive TRP channels. Channel activity was evaluated mainly using TRP channel-expressing HEK cells and calcium imaging. Herein, it was shown that 1 acts as an antagonist for TRPV1 and TRPM8 but as an agonist for TRPA1 (EC50, 8 μM). The compound competitively blocked capsaicin binding to TRPV1 (IC50, 50 μM). Voacangine (1) competitively inhibited the binding of menthol to TRPM8 (IC50, 9 μM), but it showed noncompetitive inhibition against icilin (IC50, 7 μM). Moreover, the compound selectively abrogated chemical agonist-induced TRPM8 activation and did not affect cold-induced activation. Among these effects, the TRPM8 inhibition profile is unique and noteworthy, because to date no studies have reported a menthol competitive inhibitor of TRPM8 derived from a natural source. Furthermore, this is the first report of a stimulus-selective TRPM8 antagonist. Accordingly, 1 may contribute to the development of a novel class of stimulus-selective TRPM8 blockers. PMID:24484240

  9. ECOLOGICAL RISK ASSESSMENT AND THE PRECAUTIONARY PRINCIPLE

    EPA Science Inventory

    The Precautionary Principle, generated during the late 1980s as a unifying principle for regulating discharge of hazardous material into the North Sea, has been broadened to include a shifting of the burden of proof to the proponent of a proposed activity, adoption of a more holi...

  10. TLR9 Activation Is Triggered by the Excess of Stimulatory versus Inhibitory Motifs Present in Trypanosomatidae DNA

    PubMed Central

    Rocha, Eduardo P.C.; Mériaux, Véronique; Maréchal, Vincent; Escoll, Pedro; Goyard, Sophie; Cavaillon, Jean-Marc; Manoury, Bénédicte; Doyen, Noëlle

    2014-01-01

    DNA sequences purified from distinct organisms, e.g. non vertebrate versus vertebrate ones, were shown to differ in their TLR9 signalling properties especially when either mouse bone marrow-derived- or human dendritic cells (DCs) are probed as target cells. Here we found that the DC-targeting immunostimulatory property of Leishmania major DNA is shared by other Trypanosomatidae DNA, suggesting that this is a general trait of these eukaryotic single-celled parasites. We first documented, in vitro, that the low level of immunostimulatory activity by vertebrate DNA is not due to its limited access to DCs' TLR9. In addition, vertebrate DNA inhibits the activation induced by the parasite DNA. This inhibition could result from the presence of competing elements for TLR9 activation and suggests that DNA from different species can be discriminated by mouse and human DCs. Second, using computational analysis of genomic DNA sequences, it was possible to detect the presence of over-represented inhibitory and under-represented stimulatory sequences in the vertebrate genomes, whereas L. major genome displays the opposite trend. Interestingly, this contrasting features between L. major and vertebrate genomes in the frequency of these motifs are shared by other Trypanosomatidae genomes (Trypanosoma cruzi, brucei and vivax). We also addressed the possibility that proteins expressed in DCs could interact with DNA and promote TLR9 activation. We found that TLR9 is specifically activated with L. major HMGB1-bound DNA and that HMGB1 preferentially binds to L. major compared to mouse DNA. Our results highlight that both DNA sequence and vertebrate DNA-binding proteins, such as the mouse HMGB1, allow the TLR9-signaling to be initiated and achieved by Trypanosomatidae DNA. PMID:25392997

  11. SU-E-T-590: An Activation Study of Materials and Devices Present in a Proton Treatment Room

    SciTech Connect

    Spitznagel, D

    2014-06-01

    Purpose: The use of protons for radiation therapy is growing rapidly. One consequence of protons interacting with different media is activation. These nuclear reactions induced by the protons, scattered neutrons, and gamma rays, activate different materials encountered, particularly by the therapists. The purpose of this study was to examine the derived nuclides from the activation, and also the decay rate. Methods: The study was conducted in our proton therapy facility. Protons are derived from a synchrocyclotron and pass through field shipping systems, apertures, and range compensators to define the beam within the patient.Included materials of concerns measured; the patient support couch, sheet rock in the wall, solid plastics used for quality assurance and dosimetry, and the passive scattering system itself, which includes brass apertures, and Lucite or blue wax compensators. All devices were studied post irradiation using gamma spectroscopy to determine the nuclides, and a sodium iodine scintillation detector to measure decay, particularly when the dose rate fell to background levels. Results: We have also determined from the measurements we will maintain brass apertures for three months before sending them for scrap. Some of the radionuclides arrived from these measurements included Na-22 for the blue wax compensator, C1-34m for the sheetrock, and Sc-44 and Co-60 for the brass apertures. We found compensators made out of Lucite or wax decayed to background in 2 hours. The patient support couch decayed to background in approximately 40 minutes, and sheet rock decayed in 80 minutes. In terms of the aperture layers, the most proximal aperture slab had much higher activity than the distal slab. Also the proximal sides of the slabs were much more activate than the distal. Conclusion: We have given proper instruction to therapists performing quality assurance in terms of the handled plastics, and to handle apertures rapidly as possible.

  12. Magnesium lithospermate B and rosmarinic acid, two compounds present in Salvia miltiorrhiza, have potent antiviral activity against enterovirus 71 infections.

    PubMed

    Chung, Yi-Ching; Hsieh, Feng-Chia; Lin, Ying-Ju; Wu, Tzong-Yuan; Lin, Cheng-Wen; Lin, Ching-Ting; Tang, Nou-Ying; Jinn, Tzyy-Rong

    2015-05-15

    The aim of this study was to identify the active ingredients responsible for the anti-EV71 activity produced by Salvia miltiorrhiza extracts. A pGS-EV71 IRES-based bicistronic reporter assay platform was used for rapid analysis of compounds that could specifically inhibit EV71 viral IRES-mediated translation. The analysis identified 2 caffeic acid derivatives, magnesium lithospermate B (MLB) and rosmarinic acid (RA), which suppressed EV71 IRES-mediated translation at concentrations of 30μg/ml. We also found that MLB and RA inhibited EV71 infection when they were added to RD cells during the viral absorption stage. MLB had a low IC50 value of 0.09mM and a high TI value of 10.52. In contrast, RA had an IC50 value of 0.50mM with a TI value of 2.97. MLB and RA (100µg/ml) also reduced EV71 viral particle production and significantly decreased VP1 protein production. We propose that these two derivatives inhibit EV71 viral entry into cells and viral IRES activity, thereby reducing viral particle production and viral RNA expression and blocking viral VP1 protein translation. This study provides useful information for the development of anti-EV71 assays and reagents by demonstrating a convenient EV71 IRES-based bicistronic assay platform to screen for anti-EV71 IRES activity, and also reports 2 compounds, MLB and RA, which are responsible for the anti-EV71 activity of S. miltiorrhiza. PMID:25773498

  13. Identification and characterization of a DNA primase activity present in herpes simplex virus type 1-infected HeLa cells

    SciTech Connect

    Holmes, A.M.; Wietstock, S.M.; Ruyechan, W.T. )

    1988-03-01

    A novel DNA primase activity has been identified in HeLa cells infected with herpes simplex virus type 1 (HSV-1). Such an activity has not been detected in mock-infected cells. The primase activity coeluted with a portion of HSV-1 DNA polymerase from single-stranded DNA agarose columns loaded with high-salt extracts derived from infected cells. This DNA primase activity could be distinguished from host HeLa cell DNA primase by several criteria. First, the pH optimum of the HSV primase was relatively broad and peaked at 8.2 to 8.7 pH units. Second, freshly isolated HSV DNA primase was less salt sensitive than the HeLa primase. Third, antibodies raised against individual peptides of the calf thymus DNA polymerase:primase complex cross-reacted with the HeLa primase but did not react with the HSV DNA primase. Fourth, freshly prepared HSV DNA primase appeared to be associated with the HSV polymerase, but after storage at 4{degree}C for several weeks, the DNA primase separated from the viral DNA polymerase. This free DNA primase had an apparent molecular size of approximately 40 kilodaltons, whereas free HeLa DNA primase had an apparent molecular size of approximately 110 kilodaltons. On the basis of these data, the authors believe that the novel DNA primase activity in HSV-infected cells may be virus coded and that this enzyme represents a new and important function involved in the replication of HSV DNA.

  14. Trace Hydrophobic Organic Chemicals Present in Pennsylvania Groundwater are Correlated with Geogenic Brines rather than Hydraulic Fracturing Active Zones

    NASA Astrophysics Data System (ADS)

    Drollette, B.; Shregglman, K.; D'Ambro, E.; Elsner, M.; Warner, N. R.; O'Connor, M.; Karatum, O.; Vengosh, A.; Jackson, R. B.; Darrah, T.; Plata, D.

    2014-12-01

    Recent studies demonstrated that deep Marcellus shale brines migrate into shallow groundwater aquifers, presumably via fractures in the subsurface that exist independent of any gas extraction activities. However, whereas many inorganic species are conservative tracers, hydrophobic organic compounds are both sorptive and reactive, and geogenic organic chemicals may not survive transport from deep shales to the subsurface. Here, 40 shallow groundwater samples from private wells in Northeastern Pennsylvania were analyzed for volatile organic compounds (VOCs) and gasoline range organic compounds (GRO), and 17 were analyzed for VOCs, GRO, and diesel range organic compounds (DRO). BTEX compounds (i.e., benzene, toluene, ethylbenzene, and xylenes) were detected in 6 of 40 samples at concentrations orders of magnitude below EPA maximum contaminant levels (e.g., << 5 ppb) and did not spatially correlate with distance to the nearest active hydraulic fracturing well. GRO was detected in 10 of 40 samples at concentrations as high as 8.8 ± 0.4 ppb and did not correlate with distance to the nearest hydraulic fracturing well (p = 0.24) nor in active fracturing zones, which we defined as sample locations less than 1 km from a well (p = 0.60). However, GRO was strongly correlated (p = 0.004) with shallow groundwater with Marcellus Shale inorganic chemical character, as delineated by inorganic chemical analysis. DRO was detected in all 17 samples up to 158 ± 4 ppb and did not spatially correlate with distance to the nearest hydraulic fracturing well (p = 0.74), nor active zones (p = 0.61). Similar to GRO, DRO did correlate with shallow groundwater containing Marcellus Shale character with moderate significance (p = 0.08). These results indicate that: (a) hydrophobic organic chemicals can survive transport from the deep subsurface to shallow groundwaters, and (b) transport of these compounds is not detectably enhanced by hydraulic fracturing activities in Northeastern PA as of the

  15. Mentoring: Contemporary Principles and Issues.

    ERIC Educational Resources Information Center

    Bey, Theresa M., Ed.; Holmes, C. Thomas, Ed.

    In the spirit of educational reform efforts, an initiative exists to restructure the education of teachers through collaborative action, using mentoring to build alliances. This monograph, based on contemporary principles and issues of mentoring, presents ways to conceptualize the professional preparation and development of teachers. Following a…

  16. Activation of carbon dioxide by a terminal uranium-nitrogen bond in the gas-phase: a demonstration of the principle of microscopic reversibility.

    PubMed

    Dau, Phuong D; Armentrout, P B; Michelini, Maria C; Gibson, John K

    2016-03-14

    Activation of CO2 is demonstrated by its spontaneous dissociative reaction with the gas-phase anion complex NUOCl2(-), which can be considered as NUO(+) coordinated by two chloride anion ligands. This reaction was previously predicted by density functional theory to occur exothermically, without barriers above the reactant energy. The present results demonstrate the validity of the prediction of microscopic reversibility, and provide a rare case of spontaneous dissociative addition of CO2 to a gas-phase complex. The activation of CO2 by NUOCl2(-) proceeds by conversion of a U[triple bond, length as m-dash]N bond to a U[double bond, length as m-dash]O bond and creation of an isocyanate ligand to yield the complex UO2(NCO)Cl2(-), in which uranyl, UO2(2+), is coordinated by one isocyanate and two chloride anion ligands. This activation of CO2 by a uranium(vi) nitride complex is distinctive from previous reports of oxidative insertion of CO2 into lower oxidation state U(iii) or U(iv) solid complexes, during which both C-O bonds remain intact. This unusual observation of spontaneous addition and activation of CO2 by NUOCl2(-) is a result of the high oxophilicity of uranium. If the computed Gibbs free energy of the reaction pathway, rather than the energy, is considered, there are barriers above the reactant asymptotes such that the observed reaction should not proceed under thermal conditions. This result provides a demonstration that energy rather than Gibbs free energy determines reactivity under low-pressure bimolecular conditions. PMID:26898535

  17. Anti-Streptococcal activity of Brazilian Amazon Rain Forest plant extracts presents potential for preventive strategies against dental caries

    PubMed Central

    da SILVA, Juliana Paola Corrêa; de CASTILHO, Adriana Lígia; SARACENI, Cíntia Helena Couri; DÍAZ, Ingrit Elida Collantes; PACIÊNCIA, Mateus Luís Barradas; SUFFREDINI, Ivana Barbosa

    2014-01-01

    Caries is a global public health problem, whose control requires the introduction of low-cost treatments, such as strong prevention strategies, minimally invasive techniques and chemical prevention agents. Nature plays an important role as a source of new antibacterial substances that can be used in the prevention of caries, and Brazil is the richest country in terms of biodiversity. Objective In this study, the disk diffusion method (DDM) was used to screen over 2,000 Brazilian Amazon plant extracts against Streptococcus mutans. Material and Methods Seventeen active plant extracts were identified and fractionated. Extracts and their fractions, obtained by liquid-liquid partition, were tested in the DDM assay and in the microdilution broth assay (MBA) to determine their minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs). The extracts were also subjected to antioxidant analysis by thin layer chromatography. Results EB271, obtained from Casearia spruceana, showed significant activity against the bacterium in the DDM assay (20.67±0.52 mm), as did EB1129, obtained from Psychotria sp. (Rubiaceae) (15.04±2.29 mm). EB1493, obtained from Ipomoea alba, was the only extract to show strong activity against Streptococcus mutans (0.08 mg/mLactive extracts, discovered in the Amazon rain forest, show potential as sources of new antibacterial agents for use as chemical coadjuvants in prevention strategies to treat caries. PMID:24676578

  18. Vibrational imaging of glucose uptake activity in live cells and tissues by stimulated Raman scattering microscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hu, Fanghao; Chen, Zhixing; Zhang, Luyuan; Shen, Yihui; Wei, Lu; Min, Wei

    2016-03-01

    Glucose is consumed as an energy source by virtually all living organisms, from bacteria to humans. Its uptake activity closely reflects the cellular metabolic status in various pathophysiological transformations, such as diabetes and cancer. Extensive efforts such as positron emission tomography, magnetic resonance imaging and fluorescence microscopy have been made to specifically image glucose uptake activity but all with technical limitations. Here, we report a new platform to visualize glucose uptake activity in live cells and tissues with subcellular resolution and minimal perturbation. A novel glucose analogue with a small alkyne tag (carbon-carbon triple bond) is developed to mimic natural glucose for cellular uptake, which can be imaged with high sensitivity and specificity by targeting the strong and characteristic alkyne vibration on stimulated Raman scattering (SRS) microscope to generate a quantitative three dimensional concentration map. Cancer cells with differing metabolic characteristics can be distinguished. Heterogeneous uptake patterns are observed in tumor xenograft tissues, neuronal culture and mouse brain tissues with clear cell-cell variations. Therefore, by offering the distinct advantage of optical resolution but without the undesirable influence of bulky fluorophores, our method of coupling SRS with alkyne labeled glucose will be an attractive tool to study energy demands of living systems at the single cell level.

  19. Engaging nursing home residents with dementia in activities: The effects of modeling, presentation order, time of day, and setting characteristics

    PubMed Central

    Cohen-Mansfield, Jiska; Thein, Khin; Dakheel-Ali, Maha; Marx, Marcia S.

    2011-01-01

    We examined the impact of setting characteristics and presentation effects on engagement with stimuli in a group of 193 nursing home residents with dementia (recruited from a total of seven nursing homes). Engagement was assessed through systematic observations using the Observational Measurement of Engagement (OME), and data pertaining to setting characteristics (background noise, light, and number of persons in proximity) were recorded via the environmental portion of the Agitation Behavior Mapping Inventory (ABMI; Cohen-Mansfield, Werner, & Marx, (1989). An observational study of agitation in agitated nursing home residents. International Psychogeriatrics, 1, 153–165). Results revealed that study participants were engaged more often with moderate levels of sound and in the presence of a small group of people (from four to nine people). As to the presentation effects, multiple presentations of the same stimulus were found to be appropriate for the severely impaired as well as the moderately cognitively impaired. Moreover, modeling of the appropriate behavior significantly increased engagement, with the severely cognitively impaired residents receiving the greatest benefit from modeling. These findings have direct implications for the way in which caregivers could structure the environment in the nursing home and how they could present stimuli to residents in order to optimize engagement in persons with dementia. PMID:20455123

  20. Present concept on current water protection and remediation activities for the areas contaminated by the 1986 Chernobyl accident

    SciTech Connect

    Voitsekhovitch, O.; Prister, B.; Nasvit, O.; Los, I.; Berkovski, V.

    1996-07-01

    The results of radiation monitoring data and migration pathway analysis of water bodies within areas affected by the 1986 Chernobyl accident provide a unique opportunity for decision-makers working in other extensively contaminated regions to optimize their approaches to surface and groundwater protection. Most engineering measures within the Chernobyl 30-km exclusion zone were focused on preventing secondary contamination of surface and groundwater from entering the Pripyat River and the Kiev Reservoir. However, implementation of these measures required huge financial and human resources. Therefore, lessons about post-accidental water protection activities can be learned form the Chernobyl example. 9 refs., 9 figs.

  1. Unusual Late Presentation of Hemophilia A in an Active Duty U.S. Marine Following Open Shoulder Surgery.

    PubMed

    Shapiro, Bennett H; Minter, Alex R; McDonald, Lucas S

    2015-12-01

    Hemophilia A is clotting disorder affecting 8:100,000 males in the United States. It is an X-linked recessive genetic disorder, although about one-third of cases occur spontaneously without known family history. Because of the risk of uncontrolled hemorrhage on the battlefield, hemophilia and other bleeding disorders exclude individuals from service in the U.S. military. We report a case of an active duty U.S. Marine whose underlying diagnosis of Hemophilia A was discovered and treated by a multidisciplinary team of orthopedic surgeons and hematologists following recurrent hematomas after open rotator cuff surgery. The patient gave informed consent for publication. PMID:26633674

  2. Present concept on current water protection and remediation activities for the areas contaminated by the 1986 Chernobyl accident.

    PubMed

    Voitsekhovitch, O; Prister, B; Nasvit, O; Los, I; Berkovski, V

    1996-07-01

    The results of radiation monitoring data and migration pathway analysis of water bodies within areas affected by the 1986 Chernobyl accident provide a unique opportunity for decision-makers working in other extensively contaminated regions to optimize their approaches to surface and groundwater protection. Most engineering measures within the Chernobyl 30-km exclusion zone were focused on preventing secondary contamination of surface and groundwater from entering the Pripyat River and the Kiev Reservoir. However, implementation of these measures required huge financial and human resources. Therefore, lessons about post-accidental water protection activities can be learned from the Chernobyl example. PMID:8655324

  3. A study on the activities of a few free radicals scavenging enzymes present in five roadside plants.

    PubMed

    Mandal, M; Mukherji, S

    2001-10-01

    The road side plants are continuously exposed to the high levels of oxides of nitrogen and sulphur dioxide, emitted from automobile. Resistance to automobile exhaust pollution was studied with Nerium indicum Mill, Boerhaavia diffusa L., Amaranthus spinosus L., Cephalandra indica Naud., and Tabernaemontana divaricata L., growing on the edges of Delhi Road, National Highway 2 (NH 2) near Dankuni, West Bengal. By analysing the activities of a few enzymes like superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase and phenolic peroxidase, it appears that among the five plants examined,Amaranthus and Cephalandra are equipped with a very good scavenging system to combat effects of air pollution. PMID:12018603

  4. Fault Management Guiding Principles

    NASA Technical Reports Server (NTRS)

    Newhouse, Marilyn E.; Friberg, Kenneth H.; Fesq, Lorraine; Barley, Bryan

    2011-01-01

    Regardless of the mission type: deep space or low Earth orbit, robotic or human spaceflight, Fault Management (FM) is a critical aspect of NASA space missions. As the complexity of space missions grows, the complexity of supporting FM systems increase in turn. Data on recent NASA missions show that development of FM capabilities is a common driver for significant cost overruns late in the project development cycle. Efforts to understand the drivers behind these cost overruns, spearheaded by NASA's Science Mission Directorate (SMD), indicate that they are primarily caused by the growing complexity of FM systems and the lack of maturity of FM as an engineering discipline. NASA can and does develop FM systems that effectively protect mission functionality and assets. The cost growth results from a lack of FM planning and emphasis by project management, as well the maturity of FM as an engineering discipline, which lags behind the maturity of other engineering disciplines. As a step towards controlling the cost growth associated with FM development, SMD has commissioned a multi-institution team to develop a practitioner's handbook representing best practices for the end-to-end processes involved in engineering FM systems. While currently concentrating primarily on FM for science missions, the expectation is that this handbook will grow into a NASA-wide handbook, serving as a companion to the NASA Systems Engineering Handbook. This paper presents a snapshot of the principles that have been identified to guide FM development from cradle to grave. The principles range from considerations for integrating FM into the project and SE organizational structure, the relationship between FM designs and mission risk, and the use of the various tools of FM (e.g., redundancy) to meet the FM goal of protecting mission functionality and assets.

  5. A Review: Principles of Design and Analysis of Learning Systems

    ERIC Educational Resources Information Center

    Durney, Carl H.

    1973-01-01

    Analyzes a traditional and an innovative course in terms of learning principles, involving Erickson's management methods and Gagne's learning activities. Suggests that learning systems should be designed by applying all principles rather than emphasizing one or two of them. (CC)

  6. Nematic and blue phase liquid crystals for temperature stabilization and active optical tuning of silicon photonic devices (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Ptasinski, Joanna N.; Khoo, Iam Choon; Fainman, Yeshaiahu

    2015-10-01

    We describe the underlying theories and experimental demonstrations of passive temperature stabilization of silicon photonic devices clad in nematic liquid crystal mixtures, and active optical tuning of silicon photonic resonant structures combined with dye-doped nematic and blue phase liquid crystals. We show how modifications to the resonator device geometry allow for not only enhanced tuning of the resonator response, but also aid in achieving complete athermal operations of silicon photonic circuits. [Ref.: I.C. Khoo, "DC-field-assisted grating formation and nonlinear diffractions in methyl-red dye-doped blue phase liquid crystals," Opt. Lett. 40, 60-63 (2015); J. Ptasinski, I.C. Khoo, and Y. Fainman, "Enhanced optical tuning of modified-geometry resonators clad in blue phase liquid crystals," Opt. Lett. 39, 5435-5438 (2014); J. Ptasinski, I.C. Khoo, and Y. Fainman, "Passive Temperature Stabilization of Silicon Photonic Devices Using Liquid Crystals," Materials 7(3), 2229-2241 (2014)].

  7. A nano-confined charged layer defies the principle of electrostatic interaction.

    PubMed

    Singh, Prabhat K; Kumbhakar, Manoj; Pal, Haridas; Nath, Sukhendu

    2011-06-28

    The reactivity between two charged molecules and the activity of charged biomolecules are mainly governed by the principle of electrostatic interaction, i.e., like charges repel and opposite charges attract. In the present study it is shown that the principle of electrostatic interaction is violated in the nano-confined biomimetic environment. Thus a positively charged molecule shows more preference to a positively charged surface compared to a negatively charged surface. PMID:21594238

  8. Projecting the environmental profile of Singapore's landfill activities: Comparisons of present and future scenarios based on LCA.

    PubMed

    Khoo, Hsien H; Tan, Lester L Z; Tan, Reginald B H

    2012-05-01

    This article aims to generate the environmental profile of Singapore's Semakau landfill by comparing three different operational options associated with the life cycle stages of landfilling activities, against a 'business as usual' scenario. Before life cycle assessment or LCA is used to quantify the potential impacts from landfilling activities, an attempt to incorporate localized and empirical information into the amounts of ash and MSW sent to the landfill was made. A linear regression representation of the relationship between the mass of waste disposed and the mass of incineration ash generated was modeled from waste statistics between years 2004 and 2009. Next, the mass of individual MSW components was projected from 2010 to 2030. The LCA results highlighted that in a 'business as usual' scenario the normalized total impacts of global warming, acidification and human toxicity increased by about 2% annually from 2011 to 2030. By replacing the 8000-tonne barge with a 10000-tonne coastal bulk carrier or freighter (in scenario 2) a grand total reduction of 48% of both global warming potential and acidification can be realized by year 2030. Scenario 3 explored the importance of having a Waste Water Treatment Plant in place to reduce human toxicity levels - however, the overall long-term benefits were not as significant as scenario 2. It is shown in scenario 4 that the option of increased recycling championed over all other three scenarios in the long run, resulting in a total 58% reduction in year 2030 for the total normalized results. A separate comparison of scenarios 1-4 is also carried out for energy utilization and land use in terms of volume of waste occupied. Along with the predicted reductions in environmental burdens, an additional bonus is found in the expanded lifespan of Semakau landfill from year 2032 (base case) to year 2039. Model limitations and suggestions for improvements were also discussed. PMID:22257698

  9. Teaching the principle of biological optimization

    PubMed Central

    2013-01-01

    Among the important principles in biology that should be taught in biological engineering educational programs is the principle of optimization, what it means, why it is important, and how it comes about. This material can be presented at numerous levels throughout the curriculum. Understanding of this principle can lead biological engineers to expect it in many, if not all, biological system applications. Understanding optimization in biological systems can help understand the predictive power of evolutionary principles and what to expect from living things incorporated in designs. PMID:23421993

  10. Maximizing usability: the principles of universal design.

    PubMed

    Story, M F

    1998-01-01

    The Center for Universal Design at North Carolina State University has developed a set of seven Principles of Universal Design that may be used to guide the design process, to evaluate existing or new designs, and to teach students and practitioners. This article presents preceding design guidelines and evaluation criteria, describes the process of developing the Principles, lists The Principles of Universal Design and provides examples of designs that satisfy each, and suggests future developments that would facilitate applying the Principles to assess the usability of all types of products and environments. PMID:10181150

  11. Guiding Principles for Evaluators.

    ERIC Educational Resources Information Center

    Shadish, William R., Ed.; And Others

    1995-01-01

    The 12 articles (including an index) of this theme issue are devoted to documenting and critiquing the American Evaluation Association's "Guiding Principles for Evaluators," a code of ethics and standards. The development of these principles is traced, and their strengths and weaknesses are analyzed at general and specific levels. (SLD)

  12. Assessment Principles and Tools

    PubMed Central

    Golnik, Karl C.

    2014-01-01

    The goal of ophthalmology residency training is to produce competent ophthalmologists. Competence can only be determined by appropriately assessing resident performance. There are accepted guiding principles that should be applied to competence assessment methods. These principles are enumerated herein and ophthalmology-specific assessment tools that are available are described. PMID:24791100

  13. Principled Grammar Teaching

    ERIC Educational Resources Information Center

    Batstone, Rob; Ellis, Rod

    2009-01-01

    A key aspect of the acquisition of grammar for second language learners involves learning how to make appropriate connections between grammatical forms and the meanings which they typically signal. We argue that learning form/function mappings involves three interrelated principles. The first is the Given-to-New Principle, where existing world…

  14. Hamilton's Principle for Beginners

    ERIC Educational Resources Information Center

    Brun, J. L.

    2007-01-01

    I find that students have difficulty with Hamilton's principle, at least the first time they come into contact with it, and therefore it is worth designing some examples to help students grasp its complex meaning. This paper supplies the simplest example to consolidate the learning of the quoted principle: that of a free particle moving along a…

  15. The genetic difference principle.

    PubMed

    Farrelly, Colin

    2004-01-01

    In the newly emerging debates about genetics and justice three distinct principles have begun to emerge concerning what the distributive aim of genetic interventions should be. These principles are: genetic equality, a genetic decent minimum, and the genetic difference principle. In this paper, I examine the rationale of each of these principles and argue that genetic equality and a genetic decent minimum are ill-equipped to tackle what I call the currency problem and the problem of weight. The genetic difference principle is the most promising of the three principles and I develop this principle so that it takes seriously the concerns of just health care and distributive justice in general. Given the strains on public funds for other important social programmes, the costs of pursuing genetic interventions and the nature of genetic interventions, I conclude that a more lax interpretation of the genetic difference principle is appropriate. This interpretation stipulates that genetic inequalities should be arranged so that they are to the greatest reasonable benefit of the least advantaged. Such a proposal is consistent with prioritarianism and provides some practical guidance for non-ideal societies--that is, societies that do not have the endless amount of resources needed to satisfy every requirement of justice. PMID:15186680

  16. Government Information Policy Principles.

    ERIC Educational Resources Information Center

    Hernon, Peter

    1991-01-01

    Analyzes the utility of policy principles advanced by professional associations for public access to government information. The National Commission on Libraries and Information Science (NCLIS), the Information Industry Association (IIA), and the Office of Technology Assessment (OTA) urge the adoption of principles for the dissemination of public…

  17. Effects of rhythmic stimulus presentation on oscillatory brain activity: the physiology of cueing in Parkinson’s disease

    PubMed Central

    te Woerd, Erik S.; Oostenveld, Robert; Bloem, Bastiaan R.; de Lange, Floris P.; Praamstra, Peter

    2015-01-01

    The basal ganglia play an important role in beat perception and patients with Parkinson’s disease (PD) are impaired in perception of beat-based rhythms. Rhythmic cues are nonetheless beneficial in gait rehabilitation, raising the question how rhythm improves movement in PD. We addressed this question with magnetoencephalography recordings during a choice response task with rhythmic and non-rhythmic modes of stimulus presentation. Analyses focused on (i) entrainment of slow oscillations, (ii) the depth of beta power modulation, and (iii) whether a gain in modulation depth of beta power, due to rhythmicity, is of predictive or reactive nature. The results show weaker phase synchronisation of slow oscillations and a relative shift from predictive to reactive movement-related beta suppression in PD. Nonetheless, rhythmic stimulus presentation increased beta modulation depth to the same extent in patients and controls. Critically, this gain selectively increased the predictive and not reactive movement-related beta power suppression. Operation of a predictive mechanism, induced by rhythmic stimulation, was corroborated by a sensory gating effect in the sensorimotor cortex. The predictive mode of cue utilisation points to facilitation of basal ganglia-premotor interactions, contrasting with the popular view that rhythmic stimulation confers a special advantage in PD, based on recruitment of alternative pathways. PMID:26509117

  18. Monoclonal Antibody Combinations that Present Synergistic Neutralizing Activity: A Platform for Next-Generation Anti-Toxin Drugs

    PubMed Central

    Diamant, Eran; Torgeman, Amram; Ozeri, Eyal; Zichel, Ran

    2015-01-01

    Monoclonal antibodies (MAbs) are among the fastest-growing therapeutics and are being developed for a broad range of indications, including the neutralization of toxins, bacteria and viruses. Nevertheless, MAbs potency is still relatively low when compared to conventional polyclonal Ab preparations. Moreover, the efficacy of an individual neutralizing MAb may significantly be hampered by the potential absence or modification of its target epitope in a mutant or subtype of the infectious agent. These limitations of individual neutralizing MAbs can be overcome by using oligoclonal combinations of several MAbs with different specificities to the target antigen. Studies conducted in our lab and by others show that such combined MAb preparation may present substantial synergy in its potency over the calculated additive potency of its individual MAb components. Moreover, oligoclonal preparation is expected to be better suited to compensating for reduced efficacy due to epitope variation. In this review, the synergistic neutralization properties of combined oligoclonal Ab preparations are described. The effect of Ab affinity, autologous Fc fraction, and targeting a critical number of epitopes, as well as the unexpected contribution of non-neutralizing clones to the synergistic neutralizing effect are presented and discussed. PMID:26035486

  19. A Fragment of the LG3 Peptide of Endorepellin Is Present in the Urine of Physically Active Mining Workers: A Potential Marker of Physical Activity

    PubMed Central

    Parker, Tony J.; Sampson, Dayle L.; Broszczak, Daniel; Chng, Yee L.; Carter, Shea L.; Leavesley, David I.; Parker, Anthony W.; Upton, Zee

    2012-01-01

    Biomarker analysis has been implemented in sports research in an attempt to monitor the effects of exertion and fatigue in athletes. This study proposed that while such biomarkers may be useful for monitoring injury risk in workers, proteomic approaches might also be utilised to identify novel exertion or injury markers. We found that urinary urea and cortisol levels were significantly elevated in mining workers following a 12 hour overnight shift. These levels failed to return to baseline over 24 h in the more active maintenance crew compared to truck drivers (operators) suggesting a lack of recovery between shifts. Use of a SELDI-TOF MS approach to detect novel exertion or injury markers revealed a spectral feature which was associated with workers in both work categories who were engaged in higher levels of physical activity. This feature was identified as the LG3 peptide, a C-terminal fragment of the anti-angiogenic/anti-tumourigenic protein endorepellin. This finding suggests that urinary LG3 peptide may be a biomarker of physical activity. It is also possible that the activity mediated release of LG3/endorepellin into the circulation may represent a biological mechanism for the known inverse association between physical activity and cancer risk/survival. PMID:22457785

  20. Radiation protection principles of NCRP.

    PubMed

    Kase, Kenneth R

    2004-09-01

    The current recommendations of the National Council on Radiation Protection and Measurements (NCRP) relative to ionizing radiation are based on radiation protection principles that developed historically as information about radiation effects on human populations became available. Because the NCRP Charter states that the NCRP will cooperate with the International Commission on Radiological Protection (ICRP), the basic principles and recommendations for radiation protection of the NCRP are closely coupled with those of the ICRP. Thus, the fundamental principles of justification, optimization, and dose limitation as initially stated in ICRP Publication 26 have been adopted and applied by the NCRP in its recommendations. ICRP and NCRP recommendations on dose limitation for the general public and for occupationally exposed individuals are based on the same analyses of radiation risk, and, while similar, there are differences reflecting the aspects of radiation application and exposure circumstances unique to the United States. The NCRP has recently extended its guidance to address exposure to individuals engaged in space activities. Several reports have been issued or are in preparation to provide recommendations on dose limitation and the development of radiation safety programs to apply the radiation protection principles in space activities. The biological basis for these recommendations is provided in these and accompanying NCRP reports. Recommendations for the application of basic radiation protection principles have been made in many reports over the years. Those that are most current appear in approximately 50 reports published in the last 15 y. These address radiation safety practices in industrial and medical institutions, control of radionuclides in the environment, protection of the public, and assessment of radiation risk. Some of the aspects of these recommendations will be discussed. Current recommendations related to radiation safety practice are based

  1. American Evaluation Association: Guiding Principles for Evaluators

    ERIC Educational Resources Information Center

    American Journal of Evaluation, 2009

    2009-01-01

    The American Evaluation Association (AEA) strives to promote ethical practice in the evaluation of programs, products, personnel, and policy. This article presents the list of principles which AEA developed to guide evaluators in their professional practice. These principles are: (1) Systematic Inquiry; (2) Competence; (3) Integrity/Honesty; (4)…

  2. Integrating Computer Concepts into Principles of Accounting.

    ERIC Educational Resources Information Center

    Beck, Henry J.; Parrish, Roy James, Jr.

    A package of instructional materials for an undergraduate principles of accounting course at Danville Community College was developed based upon the following assumptions: (1) the principles of accounting student does not need to be able to write computer programs; (2) computerized accounting concepts should be presented in this course; (3)…

  3. CEP's Eleven Principles of Effective Character Education

    ERIC Educational Resources Information Center

    Lickona, Tom; Schaps, Eric; Lewis, Catherine

    2007-01-01

    There is no single script for effective character education, but there are some important basic principles. This document presents eleven principles that schools and other groups can use to plan a character education effort and to evaluate available character education programs: (1) Promotes core ethical values and supportive performance values as…

  4. Improving Construct Validity with Cognitive Psychology Principles.

    ERIC Educational Resources Information Center

    Embretson, Susan; Gorin, Joanna

    2001-01-01

    Examines testing practices in: (1) the past, in which the traditional paradigm left little room for cognitive psychology principles; (2) the present, in which testing research is enhanced by principles of cognitive psychology; and (3) the future, in which the potential of cognitive psychology should be fully realized through item design.…

  5. Protein Multifunctionality: Principles and Mechanisms

    PubMed Central

    Zaretsky, Joseph Z.; Wreschner, Daniel H.

    2008-01-01

    In the review, the nature of protein multifunctionality is analyzed. In the first part of the review the principles of structural/functional organization of protein are discussed. In the second part, the main mechanisms involved in development of multiple functions on a single gene product(s) are analyzed. The last part represents a number of examples showing that multifunctionality is a basic feature of biologically active proteins. PMID:21566747

  6. Docetaxel for non-small-cell lung cancer harboring the activated EGFR mutation with T790M at initial presentation.

    PubMed

    Yamane, Hiromichi; Ochi, Nobuaki; Yasugi, Masayuki; Tabayashi, Takayuki; Yamagishi, Tomoko; Monobe, Yasumasa; Hisamoto, Akiko; Kiura, Katsuyuki; Takigawa, Nagio

    2013-01-01

    A 72-year-old woman was referred to our hospital with Stage IV non-small-cell lung cancer (NSCLC). Chest computed tomography revealed a mass in the upper lobe of the right lung, with pleural effusion. Cytologic examination identified adenocarcinoma cells in the right pleural effusion. Furthermore, both a deletion mutation in exon 19 and a threonine-methionine substitution mutation at position 790 in exon 20 (T790M) were detected in the epidermal growth factor receptors (EGFR) in the malignant cells. As systemic chemotherapy consisting of carboplatin and pemetrexed or erlotinib proved ineffective, docetaxel monotherapy was initiated as a third-line treatment. Following salvage chemotherapy, her Eastern Cooperative Oncology Group performance status improved from 3 to 1, with tumor regression over 5 months. To the best of our knowledge, this is the first report of successful docetaxel treatment for a patient with NSCLC harboring the T790M EGFR-activating mutation identified before treatment with EGFR tyrosine kinase inhibitors. PMID:23493804

  7. Docetaxel for non-small-cell lung cancer harboring the activated EGFR mutation with T790M at initial presentation

    PubMed Central

    Yamane, Hiromichi; Ochi, Nobuaki; Yasugi, Masayuki; Tabayashi, Takayuki; Yamagishi, Tomoko; Monobe, Yasumasa; Hisamoto, Akiko; Kiura, Katsuyuki; Takigawa, Nagio

    2013-01-01

    A 72-year-old woman was referred to our hospital with Stage IV non-small-cell lung cancer (NSCLC). Chest computed tomography revealed a mass in the upper lobe of the right lung, with pleural effusion. Cytologic examination identified adenocarcinoma cells in the right pleural effusion. Furthermore, both a deletion mutation in exon 19 and a threonine–methionine substitution mutation at position 790 in exon 20 (T790M) were detected in the epidermal growth factor receptors (EGFR) in the malignant cells. As systemic chemotherapy consisting of carboplatin and pemetrexed or erlotinib proved ineffective, docetaxel monotherapy was initiated as a third-line treatment. Following salvage chemotherapy, her Eastern Cooperative Oncology Group performance status improved from 3 to 1, with tumor regression over 5 months. To the best of our knowledge, this is the first report of successful docetaxel treatment for a patient with NSCLC harboring the T790M EGFR-activating mutation identified before treatment with EGFR tyrosine kinase inhibitors. PMID:23493804

  8. The transition from hydrostatic to greater than hydrostatic fluid pressure in presently active continental hydrothermal systems in crystalline rock

    SciTech Connect

    Fournier, R.O. )

    1991-05-01

    Fluid flow at hydrostatic pressure (P{sub h}) is relatively common through fractures in silicic and in mafic crystalline rocks where temperatures are less than about 350-370C. In contrast, pore-fluid pressure (P{sub f}) > P{sub h} has been encountered at the bottom of 3 geothermal exploration wells that attained temperatures >370C (at Larderello, Italy, at Nesjavellir, Iceland, and at The Geysers, California). Chemical sealing by deposition of minerals in veins appears to have allowed the development of the high P{sub f} encountered in the above wells. The upper limit for the magnitude of P{sub f} that can be attained is controlled by either the onset of shear fracturing (where differential stress is relatively high) that reopens clogged veins, or the hydraulic opening of new or old fractures (at relatively low values of differential stress). The brittle-plastic transition for silicic rocks can occur at temperatures as high as 370-400C in tectonically active regions. In regions where high-temperature geothermal systems develop and persist, it appears that either strain rates commonly are in the range 10{sup {minus}12} to 10{sup {minus}13}, or that silicic rocks in the shallow crust generally behave rheologically more like wet quartz diorite than wet Westerly granite.

  9. Anionic Lipid Content Presents a Barrier to the Activity of ROMP-Based Synthetic Mimics of Protein Transduction Domains (PTDMs).

    PubMed

    Lis, Michael; Dorner, Franziska; Tew, Gregory N; Lienkamp, Karen

    2016-06-14

    Many biophysical studies of protein transduction domains (PTDs) and their synthetic mimics (PTDMs) focus on the interaction between the polycationic PTD(M) and anionic phospholipid surfaces. Most, but not all, of these studies suggest that these cation-anion interactions are vital for membrane activity. In this study, the effect of anionic lipid content on PTDM performance was examined for three ring-opening metathesis (ROMP)-based PTDMs with varying hydrophobicity. Using a series of dye-loaded vesicles with gradually increasing anionic lipid content, we saw that increased anionic lipid content inhibited dye release caused by these PTDMs. This result is the opposite of what was found in studies with poly- and oligo-arginine. While the effect is reduced for more hydrophobic PTDMs, it is observable even with the most hydrophobic PTDMs of our test panel. Additional experiments included dynamic light scattering and zeta potential measurements to measure size as a function of vesicle surface charge in the presence of increasing PTDM concentration and surface plasmon resonance spectroscopy to quantify binding between PTDMs and surface-bound lipid layers with varying anion content. The results from these measurements suggested that PTDM hydrophobicity, not cation-anion interactions, is the main driving force of the interaction between our PTDMs and the model membranes investigated. This suggests a model of interaction where surface association and membrane insertion are driven by PTDM hydrophobicity, while anionic lipid content serves primarily to "pin" the PTDM to the membrane surface and limit insertion. PMID:27182683

  10. Principlism and communitarianism.

    PubMed

    Callahan, D

    2003-10-01

    The decline in the interest in ethical theory is first outlined, as a background to the author's discussion of principlism. The author's own stance, that of a communitarian philosopher, is then described, before the subject of principlism itself is addressed. Two problems stand in the way of the author's embracing principlism: its individualistic bias and its capacity to block substantive ethical inquiry. The more serious problem the author finds to be its blocking function. Discussing the four scenarios the author finds that the utility of principlism is shown in the two scenarios about Jehovah's Witnesses but that when it comes to selling kidneys for transplantation and germline enhancement, principlism is of little help. PMID:14519838

  11. Mimosine, a Toxin Present in Leguminous Trees (Leucaena spp.), Induces a Mimosine-Degrading Enzyme Activity in Some Rhizobium Strains

    PubMed Central

    Soedarjo, Muchdar; Hemscheidt, Thomas K.; Borthakur, Dulal

    1994-01-01

    Thirty-seven Rhizobium isolates obtained from the nodules of leguminous trees (Leucaena spp.) were selected on the basis of their ability to catabolize mimosine, a toxin found in large quantities in the seeds, foliage, and roots of plants of the genera Leucaena and Mimosa. A new medium containing mimosine as the sole source of carbon and nitrogen was used for selection. The enzymes of the mimosine catabolic pathway were inducible and were present in the soluble fraction of the cell extract of induced cells. On the basis of a comparison of the growth rates of Rhizobium strains on general carbon and nitrogen sources versus mimosine, the toxin appears to be converted mostly to biomass and carbon dioxide. Most isolates able to grow on mimosine as a source of carbon and nitrogen are also able to utilize 3-hydroxy-4-pyridone, a toxic intermediate of mimosine degradation in other organisms. PMID:16349454

  12. Neural progenitor cells isolated from the subventricular zone present hemichannel activity and form functional gap junctions with glial cells

    PubMed Central

    Talaverón, Rocío; Fernández, Paola; Escamilla, Rosalba; Pastor, Angel M.; Matarredona, Esperanza R.; Sáez, Juan C.

    2015-01-01

    The postnatal subventricular zone (SVZ) lining the walls of the lateral ventricles contains neural progenitor cells (NPCs) that generate new olfactory bulb interneurons. Communication via gap junctions between cells in the SVZ is involved in NPC proliferation and in neuroblast migration towards the olfactory bulb. SVZ NPCs can be expanded in vitro in the form of neurospheres that can be used for transplantation purposes after brain injury. We have previously reported that neurosphere-derived NPCs form heterocellular gap junctions with host glial cells when they are implanted after mechanical injury. To analyze functionality of NPC-glial cell gap junctions we performed dye coupling experiments in co-cultures of SVZ NPCs with astrocytes or microglia. Neurosphere-derived cells expressed mRNA for at least the hemichannel/gap junction channel proteins connexin 26 (Cx26), Cx43, Cx45 and pannexin 1 (Panx1). Dye coupling experiments revealed that gap junctional communication occurred among neurosphere cells (incidence of coupling: 100%). Moreover, hemichannel activity was also detected in neurosphere cells as evaluated in time-lapse measurements of ethidium bromide uptake. Heterocellular coupling between NPCs and glial cells was evidenced in co-cultures of neurospheres with astrocytes (incidence of coupling: 91.0 ± 4.7%) or with microglia (incidence of coupling: 71.9 ± 6.7%). Dye coupling in neurospheres and in co-cultures was inhibited by octanol, a gap junction blocker. Altogether, these results suggest the existence of functional hemichannels and gap junction channels in postnatal SVZ neurospheres. In addition, they demonstrate that SVZ-derived NPCs can establish functional gap junctions with astrocytes or microglia. Therefore, cell-cell communication via gap junctions and hemichannels with host glial cells might subserve a role in the functional integration of NPCs after implantation in the damaged brain. PMID:26528139

  13. High-frequency neural activity and human cognition: past, present and possible future of intracranial EEG research

    PubMed Central

    Lachaux, Jean-Philippe; Axmacher, Nikolai; Mormann, Florian; Halgren, Eric; Crone, Nathan E.

    2013-01-01

    Human intracranial EEG (iEEG) recordings are primarily performed in epileptic patients for presurgical mapping. When patients perform cognitive tasks, iEEG signals reveal high-frequency neural activities (HFA, between around 40 Hz and 150 Hz) with exquisite anatomical, functional and temporal specificity. Such HFA were originally interpreted in the context of perceptual or motor binding, in line with animal studies on gamma-band (‘40Hz’) neural synchronization. Today, our understanding of HFA has evolved into a more general index of cortical processing: task-induced HFA reveals, with excellent spatial and time resolution, the participation of local neural ensembles in the task-at-hand, and perhaps the neural communication mechanisms allowing them to do so. This review promotes the claim that studying HFA with iEEG provides insights into the neural bases of cognition that cannot be derived as easily from other approaches, such as fMRI. We provide a series of examples supporting that claim, drawn from studies on memory, language and default-mode networks, and successful attempts of real-time functional mapping. These examples are followed by several guidelines for HFA research, intended for new groups interested by this approach. Overall, iEEG research on HFA should play an increasing role in cognitive neuroscience in humans, because it can be explicitly linked to basic research in animals. We conclude by discussing the future evolution of this field, which might expand that role even further, for instance through the use of multi-scale electrodes and the fusion of iEEG with MEG and fMRI. PMID:22750156

  14. Presentation skills for nurses.

    PubMed

    Foulkes, Mark

    2015-02-20

    This article emphasises the importance of effective presentation skills. Such skills allow nurses to share knowledge and expertise and to communicate clearly in a range of workplace scenarios. Nurses are increasingly being asked to present in formal and informal situations, such as conferences, poster presentations, job interviews, case reports and ward-based teaching. This article explores the principles underpinning the development of these skills, discusses the situations in which they could be applied and demonstrates how nurses might improve and develop as presenters. PMID:25690236

  15. Design principles for nickel-hydrogen cells and batteries

    NASA Technical Reports Server (NTRS)

    Thaller, L. H.; Manzo, M. A.; Gonzalez-Sanabria, O. D.

    1985-01-01

    Nickel-hydrogen cells and, more recently, bipolar batteries have been built by a variety of organizations. The design principles that have been used by the technology group at the NASA Lewis Research Center draw upon their extensive background in separator technology, alkaline fuel cell technology, and several alkaline cell technology areas. These design principles have been incorporated into both the more contemporary individual pressure vessel (IPV) designs that were pioneered by other groups, as well as the more recent bipolar battery designs using active cooling that are being developed at NASA Lewis Research Center and under contract. These principles are rather straightforward applications of capillary force formalisms, coupled with the slowly developing data base resulting from careful post test analyses. The objective of this overall effort is directed towards the low-earth-orbit (LEO) application where the cycle life requirements are much more severe than the geosynchronous-orbit (GEO) application. A summary of the design principles employed is presented along with a discussion of the recommendations for component pore sizes and pore size distributions, as well as suggested materials of construction. These will be made based on our experience in these areas to show how these design principles have been translated into operating hardware.

  16. Design principles for nickel-hydrogen cells and batteries

    NASA Technical Reports Server (NTRS)

    Thaller, L. H.; Manzo, M. A.; Gonzalez-Sanabria, O. D.

    1985-01-01

    Nickel-hydrogen cells and, more recently, bipolar batteries have been built by a variety of organizations. The design principles that have been used by the technology group at the NASA Lewis Research Center draw upon their extensive background in separator technology, alkaline fuel cell technology, and several alkaline cell technology areas. These design principles have been incorporated into both the more contemporary individual pressure vessel (IPV) designs that were pioneered by other groups, as well as the more recent bipolar battery designs using active cooling that are being developed at NASA Lewis Research Center and under contract. These principles are rather straightforward applications of capillary force formalisms, coupled with the slowly developing data base resulting from careful post test analyses. The objective of this overall effort is directed towards the low-Earth-orbit (LEO) application where the cycle life requirements are much more severe than the geosynchronous-orbit (GEO) application. A summary of the design principles employed is presented along with a discussion of the recommendations for component pore sizes and pore size distributions, as well as suggested materials of construction. These will be made based on our experience in these areas to show how these design principles have been translated into operating hardware.

  17. The Penny Principle.

    ERIC Educational Resources Information Center

    Farnsworth, Briant J.; Dunoskovic, Janice H.

    1980-01-01

    Granite School District, Salt Lake City, Utah, has developed an elementary consumer education program designed for infusion into regular subject matter teaching. This article presents goals and starter activities from each of the project's eight topic areas: money management, income determination, basic economics, advertising, purchasing, energy,…

  18. [Principles and criteria used by the National Evaluation Committee of Research Activity (CNEAI-Spain) for the assessment of scientific publications: 1989-2009].

    PubMed

    Ruiz-Pérez, Rafael; Delgado López-Cózar, Emilio; Jiménez-Contreras, Evaristo

    2010-11-01

    Study of the origins, philosophy and history of the criteria used to assess research activities in Spain by the CNEAI. The assessment criteria and quality evidence of publications is discussed. Results are presented on the temporal development of the criteria used, grouped by publication type (articles and books) and fields of knowledge. Between 1989-1996, assessment was based on the definition and goals set by the Spanish scientific framework and on general criteria. Between 1996-2004, the formulation of indicators began to be almost exclusively based on Journal Citation Reports (JCR). Success rates up to 2004 indicate that the evaluation criteria and publishing behaviour matched the "hard sciences", but not the Social Sciences and Economics. In 2005, the criteria used were further developed and reoriented with an eye to softening the preceding JCR-centrism by taking into consideration other databases and defining the quality criteria to be met by journals, books and conferences not included in JCR. Correspondingly, the success rates for 2007 indicate a dramatic recovery in Economics. In the last 4 years, Humanities and Social Sciences have consolidated the further opening of the criteria used with the addition of new benchmarks and the full integration of books. PMID:21044530

  19. Enhanced visible light photocatalytic activity for the hybrid MoS2/anatase TiO2(0 0 1) nanocomposite: A first-principles study

    NASA Astrophysics Data System (ADS)

    Cao, Ling; Wang, Rong; Wang, Dongxiao; Xu, Lichun; Li, Xiuyan

    2014-09-01

    First-principles calculations based on density functional theory were carried out to investigate the electronic and optical properties of the hybrid MoS2/anatase TiO2(0 0 1) nanocomposite. The influence of MoS2 hybridization on energy gap, interfacial charge transfer, and visible light response of the MoS2/TiO2(0 0 1) complex was analyzed. The hybridization of MoS2 showed an obvious red shift in the optical absorption edge and an enhanced absorption in the visible and UV light region. The efficient photosensitization of MoS2 and the stable interface between MoS2 and TiO2(0 0 1) slab could facilitate the electrons transferred from MoS2 to TiO2(0 0 1) slab, resulting in the enhanced visible light response.

  20. The effect of electronegative difference on the electronic structure and visible light photocatalytic activity of N-doped anatase TiO{sub 2} by first-principles calculations

    SciTech Connect

    Zhao Dongqiu; Huang Xiaowei; Tian Baoli; Zhou Shaomin; Li Yuncai; Du Zuliang

    2011-04-18

    The effect of electronegative difference between nitrogen and oxygen on electronic properties of N-doped anatase TiO{sub 2} has been studied using first-principles calculations. The results indicate that the valence band maximum (VBM) shifts to high energy by 0.27 eV and the band gap states composed of N 2p, O 2p, and Ti 3d states are formed through the three states entering into the gap after N doping. The interactions of three states widen and delocalize the band gap states. The raised VBM and the wide band gap states can improve the visible light photocatalytic activity.

  1. Modeling of enhanced gravity concentrators - present status

    SciTech Connect

    A.K. Majumder; J.P. Barnwal

    2006-01-15

    The majority of the newly developed enhanced gravity concentrators (EGCs) have tremendous potentials for various applications. Therefore, the performance evaluation of these concentrators treating various minerals, coals, heavy metal recovery from tailing dams, etc., have become an active research topic. Several attempts have also been made to develop appropriate mathematical models of individual concentrators. Despite all these efforts, these concentrators have yet to find the widespread applications they deserve. The present status of modeling these EGCs with a brief description of the operating principles and the present applications are, therefore, reviewed in this article. Research needs in this direction are also highlighted.

  2. Archimedes' Principle in Action

    ERIC Educational Resources Information Center

    Kires, Marian

    2007-01-01

    The conceptual understanding of Archimedes' principle can be verified in experimental procedures which determine mass and density using a floating object. This is demonstrated by simple experiments using graduated beakers. (Contains 5 figures.)

  3. Chemical Principles Exemplified

    ERIC Educational Resources Information Center

    Plumb, Robert C.

    1972-01-01

    Collection of two short descriptions of chemical principles seen in life situations: the autocatalytic reaction seen in the bombardier beetle, and molecular potential energy used for quick roasting of beef. Brief reference is also made to methanol lighters. (PS)

  4. Global ethics and principlism.

    PubMed

    Gordon, John-Stewart

    2011-09-01

    This article examines the special relation between common morality and particular moralities in the four-principles approach and its use for global ethics. It is argued that the special dialectical relation between common morality and particular moralities is the key to bridging the gap between ethical universalism and relativism. The four-principles approach is a good model for a global bioethics by virtue of its ability to mediate successfully between universal demands and cultural diversity. The principle of autonomy (i.e., the idea of individual informed consent), however, does need to be revised so as to make it compatible with alternatives such as family- or community-informed consent. The upshot is that the contribution of the four-principles approach to global ethics lies in the so-called dialectical process and its power to deal with cross-cultural issues against the background of universal demands by joining them together. PMID:22073817

  5. Presentation Timer

    2010-06-23

    Abstract Conferences and Meetings feature many presentations on a tight schedule. The Session Timer system provides an electronic display for showing the remaining time in a presentation. It provides continuous feedback so the speaker can judge the pace throughout a presentation. The timer automates the job so the session chairman does not have to awkwardly interrupt the speaker.

  6. Principles of Tendon Transfer.

    PubMed

    Wilbur, Danielle; Hammert, Warren C

    2016-08-01

    Tendon transfers provide a substitute, either temporary or permanent, when function is lost due to neurologic injury in stroke, cerebral palsy or central nervous system lesions, peripheral nerve injuries, or injuries to the musculotendinous unit itself. This article reviews the basic principles of tendon transfer, which are important when planning surgery and essential for an optimal outcome. In addition, concepts for coapting the tendons during surgery and general principles to be followed during the rehabilitation process are discussed. PMID:27387072

  7. Principles for system level electrochemistry

    NASA Technical Reports Server (NTRS)

    Thaller, L. H.

    1986-01-01

    The higher power and higher voltage levels anticipated for future space missions have required a careful review of the techniques currently in use to preclude battery problems that are related to the dispersion characteristics of the individual cells. Not only are the out-of-balance problems accentuated in these larger systems, but the thermal management considerations also require a greater degree of accurate design. Newer concepts which employ active cooling techniques are being developed which permit higher rates of discharge and tighter packing densities for the electrochemical components. This paper will put forward six semi-independent principles relating to battery systems. These principles will progressively address cell, battery and finally system related aspects of large electrochemical storage systems.

  8. Basic Concepts and Principles of Marketing.

    ERIC Educational Resources Information Center

    Beder, Hal

    1986-01-01

    Presents an overview of marketing concepts and principles. These include (1) organizational objectives, (2) exchange, (3) value, (4) market segmentation, (5) market position, (6) consumer analysis, (7) product, (8) promotion, (9) place, and (10) price. (CH)

  9. Principles of optical-data processing techniques

    NASA Technical Reports Server (NTRS)

    Shulman, A. R.

    1968-01-01

    Document presents optical-data processing information on a level which will convey the basic principles involved to those having a general technical background. Mathematical discussions are included but are not required for a basic understanding.

  10. Teaching Principles of Economics Without Lectures

    ERIC Educational Resources Information Center

    McConnell, Campbell R.; Lamphear, Charles

    1969-01-01

    Presents important evidence thatstudents taking principles of economics with lectures, and those taking the course on a lectureless basis performed equally well on an intensive battery of objective examinations." (Editor)

  11. Application of fMRI to obesity research: differences in reward pathway activation measured with fMRI BOLD during visual presentation of high and low calorie foods

    NASA Astrophysics Data System (ADS)

    Tsao, Sinchai; Adam, Tanja C.; Goran, Michael I.; Singh, Manbir

    2012-03-01

    The factors behind the neural mechanisms that motivate food choice and obesity are not well known. Furthermore, it is not known when these neural mechanisms develop and how they are influenced by both genetic and environmental factors. This study uses fMRI together with clinical data to shed light on the aforementioned questions by investigating how appetite-related activation in the brain changes with low versus high caloric foods in pre-pubescent girls. Previous studies have shown that obese adults have less striatal D2 receptors and thus reduced Dopamine (DA) signaling leading to the reward-deficit theory of obesity. However, overeating in itself reduces D2 receptor density, D2 sensitivity and thus reward sensitivity. The results of this study will show how early these neural mechanisms develop and what effect the drastic endocrinological changes during puberty has on these mechanisms. Our preliminary results showed increased activations in the Putamen, Insula, Thalamus and Hippocampus when looking at activations where High Calorie > Low Calorie. When comparing High Calorie > Control and Low Calorie > Control, the High > Control test showed increased significant activation in the frontal lobe. The Low > Control also yielded significant activation in the Left and Right Fusiform Gyrus, which did not appear in the High > Control test. These results indicate that the reward pathway activations previously shown in post-puberty and adults are present in pre-pubescent teens. These results may suggest that some of the preferential neural mechanisms of reward are already present pre-puberty.

  12. Dark matter and the equivalence principle

    NASA Technical Reports Server (NTRS)

    Frieman, Joshua A.; Gradwohl, Ben-Ami

    1993-01-01

    A survey is presented of the current understanding of dark matter invoked by astrophysical theory and cosmology. Einstein's equivalence principle asserts that local measurements cannot distinguish a system at rest in a gravitational field from one that is in uniform acceleration in empty space. Recent test-methods for the equivalence principle are presently discussed as bases for testing of dark matter scenarios involving the long-range forces between either baryonic or nonbaryonic dark matter and ordinary matter.

  13. [The Present Status of, and Issues Related to, Mental Health Activities in the Ishinomaki Region, with a Focus on Outreach Activities].

    PubMed

    Hara, Keizo

    2015-01-01

    The Great East Japan Earthquake was a colossal event, registering a magnitude of 9.0 and causing huge tsunami that in some places were more than 40 meters in height. As of March 31, 2014, the number of dead nationwide stood at 15,882, while 2,668 persons were listed as missing; 3,089 other deaths have also been classified as being disaster-related. There were 5,500 victims in the Ishinomaki area alone. The disaster, comprising the earthquake itself, the subsequent tsunami, fires, and the nuclear power plant accident, was a combined natural and man-made catastrophe of epic proportions, affecting a broad, underpopulated region. Those hit by the disaster were affected not only by the loss of life, but also the loss of homes and livelihoods. These people experience psychological stress, fear, and anxiety as a result of lifestyle and environmental changes associated with moving from evacuation areas to prefab temporary housing, or the homes of parents, siblings, relatives, friends, or acquaintances, followed by attempts to rebuild their own homes. Other changes, such as the loss of employment, the transition to new workplaces, or having to change schools, also take a psychological and emotional toll. Delays in the construction of new housing and the resulting prolongation of life as evacuees only serve to increase anxiety and the sense of stagnation. With the above as a backdrop, the author will report on activities being conducted by his organization, particularly outreach efforts. PMID:26524874

  14. Science Activities in Energy: Conservation.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 14 activities relating to energy conservation. Activities are simple, concrete experiments for fourth, fifth and sixth grades, which illustrate principles and problems relating to energy. Each activity is outlined on a simple card which is introduced by a question. A teacher's…

  15. Exceptional activity of sub-nm Pt clusters on CdS for photocatalytic hydrogen production: A combined of experimental and first-principles study

    SciTech Connect

    Wu, Qiyuan; Su, Dong; Xiong, Shangmin; Shen, Peichuan; Zhao, Shen; Li, Yan; Orlov, Alexander

    2014-12-24

    In this work we have explored a new concept of substantially increasing photocatalytic activity for H₂ production of conventional semiconductors by modifying them with sub-nm Pt particles. By combining both experimental and theoretical approaches, we have also developed new mechanistic insights into the 17 times increase in photocatalytic activity of Pt modified CdS catalysts.

  16. The precautionary principle and medical decision making.

    PubMed

    Resnik, David B

    2004-06-01

    The precautionary principle is a useful strategy for decision-making when physicians and patients lack evidence relating to the potential outcomes associated with various choices. According to a version of the principle defended here, one should take reasonable measures to avoid threats that are serious and plausible. The reasonableness of a response to a threat depends on several factors, including benefit vs. harm, realism, proportionality, and consistency. Since a concept of reasonableness plays an essential role in applying the precautionary principle, this principle gives physicians and patients a decision-making strategy that encourages the careful weighing and balancing of different values that one finds in humanistic approaches to clinical reasoning. Properly understood, the principle presents a worthwhile alternative to approaches to clinical reasoning that apply expected utility theory to decision problems. PMID:15512973

  17. The validity of the extended energy principle

    SciTech Connect

    Chance, M.S.; Johnson, J.L.; Kulsrud, R.M.

    1994-04-01

    A recent analysis of plasma stability based on modifications of the extended energy principle for magnetohydrodynamic stability led to conclusions that are too optimistic. The original interpretation of this principle is indeed applicable. The present analysis demonstrates explicitly the fallacy of using the wrong functional for {delta}W in the extended energy principle. It then shows that the original energy principle functional {delta}W{sub B} is also obtained for a model in which a surface mass is incorporated to provide pressure balance. This work therefore indicates, but does not prove, that the eigenfunctions that are obtained from a minimization of the extended energy principle with the proper kinetic energy norm provide a good representation of what would be achieved with an exact treatment.

  18. Two Fundamental Principles of Nature's Interactions

    NASA Astrophysics Data System (ADS)

    Ma, Tian; Wang, Shouhong

    2014-03-01

    In this talk, we present two fundamental principles of nature's interactions, the principle of interaction dynamics (PID) and the principle of representation invariance (PRI). Intuitively, PID takes the variation of the action functional under energy-momentum conservation constraint. PID offers a completely different and natural way of introducing Higgs fields. PRI requires that physical laws be independent of representations of the gauge groups. These two principles give rise to a unified field model for four interactions, which can be naturally decoupled to study individual interactions. With these two principles, we are able to derive 1) a unified theory for dark matter and dark energy, 2) layered strong and weak interaction potentials, and 3) the energy levels of subatomic particles. Supported in part by NSF, ONR and Chinese NSF.

  19. First principles calculations on oxygen vacant hydrated α-MnO2 for activating water oxidation and its self-healing mechanism.

    PubMed

    Ganesan, Kruthika; Murugan, P

    2016-08-10

    Understanding the mechanism behind water oxidation is the prime requirement for designing better catalysts for electrochemical energy devices. In this work, we demonstrate by employing first principles calculations that an initial step of water oxidation is observed to be associated with the dissociation of water dimers into hydronium and hydroxide ions, in the tunnel of a hydrated α-MnO2 compound with an oxygen vacancy. The former ion is intercalated within the network, while the latter ion occupies the oxygen vacant site and interacts strongly with the Mn atoms. Based on our calculations, the factor responsible for this dissociation of water molecules is observed to be the presence of mixed charge states of Mn atoms in the triangular lattice. Further, the coulombic attraction of a hydronium ion with a water molecule leads to the formation of a Zundel cation in the tunnel, while by dehydrogenating the adsorbed hydroxide ion, the self-healing property of the compound is achieved along with another hydronium ion as a reaction product. These cations can be exchanged with Li(+) ions. Thus, the protonic moieties formed in the tunnel of α-MnO2 leads to niche applications in the field of fuel cells and lithium ion batteries. PMID:27447447

  20. 3,4,5-Trihydroxy benzoic acid (gallic acid), the hepatoprotective principle in the fruits of Terminalia belerica-bioassay guided activity.

    PubMed

    Anand, K K; Singh, B; Saxena, A K; Chandan, B K; Gupta, V N; Bhardwaj, V

    1997-10-01

    Compound I isolated from fraction TB5 of Terminalia belerica and finally identified as 3,4,5-trihydroxy benzoic acid (gallic acid) was evaluated for its hepatoprotective activity against carbon tetrachloride (CCl4)-induced physiological and biochemical alterations in the liver. The main parameters studied were hexobarbitone-induced sleep, zoxazolamine induced paralysis, serum levels of transaminases and bilirubin. The hepatic markers assessed were lipid peroxidation, drug metabolising enzymes, glucose-6-phosphatase and triglycerides. Administration of Compound I led to significant reversal of majority of the altered parameters. Our results confirm the presence of hepatoprotective activity in altered parameters. Our results confirm the presence of hepatoprotective activity in Compound I. PMID:9425622

  1. What Metadata Principles Apply to Scientific Data?

    NASA Astrophysics Data System (ADS)

    Mayernik, M. S.

    2014-12-01

    Information researchers and professionals based in the library and information science fields often approach their work through developing and applying defined sets of principles. For example, for over 100 years, the evolution of library cataloging practice has largely been driven by debates (which are still ongoing) about the fundamental principles of cataloging and how those principles should manifest in rules for cataloging. Similarly, the development of archival research and practices over the past century has proceeded hand-in-hand with the emergence of principles of archival arrangement and description, such as maintaining the original order of records and documenting provenance. This project examines principles related to the creation of metadata for scientific data. The presentation will outline: 1) how understandings and implementations of metadata can range broadly depending on the institutional context, and 2) how metadata principles developed by the library and information science community might apply to metadata developments for scientific data. The development and formalization of such principles would contribute to the development of metadata practices and standards in a wide range of institutions, including data repositories, libraries, and research centers. Shared metadata principles would potentially be useful in streamlining data discovery and integration, and would also benefit the growing efforts to formalize data curation education.

  2. The traveltime holographic principle

    NASA Astrophysics Data System (ADS)

    Huang, Yunsong; Schuster, Gerard T.

    2015-01-01

    Fermat's interferometric principle is used to compute interior transmission traveltimes τpq from exterior transmission traveltimes τsp and τsq. Here, the exterior traveltimes are computed for sources s on a boundary B that encloses a volume V of interior points p and q. Once the exterior traveltimes are computed, no further ray tracing is needed to calculate the interior times τpq. Therefore this interferometric approach can be more efficient than explicitly computing interior traveltimes τpq by ray tracing. Moreover, the memory requirement of the traveltimes is reduced by one dimension, because the boundary B is of one fewer dimension than the volume V. An application of this approach is demonstrated with interbed multiple (IM) elimination. Here, the IMs in the observed data are predicted from the migration image and are subsequently removed by adaptive subtraction. This prediction is enabled by the knowledge of interior transmission traveltimes τpq computed according to Fermat's interferometric principle. We denote this principle as the `traveltime holographic principle', by analogy with the holographic principle in cosmology where information in a volume is encoded on the region's boundary.

  3. Applying the four principles.

    PubMed

    Macklin, R

    2003-10-01

    Gillon is correct that the four principles provide a sound and useful way of analysing moral dilemmas. As he observes, the approach using these principles does not provide a unique solution to dilemmas. This can be illustrated by alternatives to Gillon's own analysis of the four case scenarios. In the first scenario, a different set of factual assumptions could yield a different conclusion about what is required by the principle of beneficence. In the second scenario, although Gillon's conclusion is correct, what is open to question is his claim that what society regards as the child's best interest determines what really is in the child's best interest. The third scenario shows how it may be reasonable for the principle of beneficence to take precedence over autonomy in certain circumstances, yet like the first scenario, the ethical conclusion relies on a set of empirical assumptions and predictions of what is likely to occur. The fourth scenario illustrates how one can draw different conclusions based on the importance given to the precautionary principle. PMID:14519836

  4. Conservation Presentation.

    ERIC Educational Resources Information Center

    Friday, Gerald

    2001-01-01

    Introduces a project in which students teach about the importance of recycling and conservation by presenting demonstrations. Includes demonstrations on water, plastic, and other recycling products such as steel. (YDS)

  5. Delivery presentations

    MedlinePlus

    ... brow first position. Most of the time, the force of contractions causes the baby to be in face-first position. It is also detected when labor does not progress. In some of these presentations, ...

  6. The actin cytoskeleton modulates the activation of iNKT cells by segregating CD1d nanoclusters on antigen-presenting cells

    PubMed Central

    Torreno-Pina, Juan A.; Manzo, Carlo; Salio, Mariolina; Aichinger, Michael C.; Oddone, Anna; Lakadamyali, Melike; Shepherd, Dawn; Besra, Gurdyal S.; Cerundolo, Vincenzo

    2016-01-01

    Invariant natural killer T (iNKT) cells recognize endogenous and exogenous lipid antigens presented in the context of CD1d molecules. The ability of iNKT cells to recognize endogenous antigens represents a distinct immune recognition strategy, which underscores the constitutive memory phenotype of iNKT cells and their activation during inflammatory conditions. However, the mechanisms regulating such “tonic” activation of iNKT cells remain unclear. Here, we show that the spatiotemporal distribution of CD1d molecules on the surface of antigen-presenting cells (APCs) modulates activation of iNKT cells. By using superresolution microscopy, we show that CD1d molecules form nanoclusters at the cell surface of APCs, and their size and density are constrained by the actin cytoskeleton. Dual-color single-particle tracking revealed that diffusing CD1d nanoclusters are actively arrested by the actin cytoskeleton, preventing their further coalescence. Formation of larger nanoclusters occurs in the absence of interactions between CD1d cytosolic tail and the actin cytoskeleton and correlates with enhanced iNKT cell activation. Importantly and consistently with iNKT cell activation during inflammatory conditions, exposure of APCs to the Toll-like receptor 7/8 agonist R848 increases nanocluster density and iNKT cell activation. Overall, these results define a previously unidentified mechanism that modulates iNKT cell autoreactivity based on the tight control by the APC cytoskeleton of the sizes and densities of endogenous antigen-loaded CD1d nanoclusters. PMID:26798067

  7. The actin cytoskeleton modulates the activation of iNKT cells by segregating CD1d nanoclusters on antigen-presenting cells.

    PubMed

    Torreno-Pina, Juan A; Manzo, Carlo; Salio, Mariolina; Aichinger, Michael C; Oddone, Anna; Lakadamyali, Melike; Shepherd, Dawn; Besra, Gurdyal S; Cerundolo, Vincenzo; Garcia-Parajo, Maria F

    2016-02-01

    Invariant natural killer T (iNKT) cells recognize endogenous and exogenous lipid antigens presented in the context of CD1d molecules. The ability of iNKT cells to recognize endogenous antigens represents a distinct immune recognition strategy, which underscores the constitutive memory phenotype of iNKT cells and their activation during inflammatory conditions. However, the mechanisms regulating such "tonic" activation of iNKT cells remain unclear. Here, we show that the spatiotemporal distribution of CD1d molecules on the surface of antigen-presenting cells (APCs) modulates activation of iNKT cells. By using superresolution microscopy, we show that CD1d molecules form nanoclusters at the cell surface of APCs, and their size and density are constrained by the actin cytoskeleton. Dual-color single-particle tracking revealed that diffusing CD1d nanoclusters are actively arrested by the actin cytoskeleton, preventing their further coalescence. Formation of larger nanoclusters occurs in the absence of interactions between CD1d cytosolic tail and the actin cytoskeleton and correlates with enhanced iNKT cell activation. Importantly and consistently with iNKT cell activation during inflammatory conditions, exposure of APCs to the Toll-like receptor 7/8 agonist R848 increases nanocluster density and iNKT cell activation. Overall, these results define a previously unidentified mechanism that modulates iNKT cell autoreactivity based on the tight control by the APC cytoskeleton of the sizes and densities of endogenous antigen-loaded CD1d nanoclusters. PMID:26798067

  8. Facilitating neurorehabilitation through principles of engagement.

    PubMed

    Danzl, Megan M; Etter, Nicole M; Andreatta, Richard D; Kitzman, Patrick H

    2012-01-01

    A primary goal of neurorehabilitation is to guide recovery of functional skills after injury through evidence-based interventions that operate to manipulate the sensorimotor environment of the client. While choice of intervention is an important decision for clinicians, we contend it is only one part of producing optimal activity-dependent neuroplastic changes. A key variable in the rehabilitation equation is engagement. Applying principles of engagement may yield greater neuroplastic changes and functional outcomes for clients. We review the principles of neuroplasticity and engagement and their potential linkage through concepts of attention and motivation and strategies such as mental practice and enriched environments. Clinical applications and challenges for enhancing engagement during rehabilitation are presented. Engagement strategies, such as building trust and rapport, motivational interviewing, enhancing the client education process, and interventions that empower clients, are reviewed. Well-controlled research is needed to test our theoretical framework and suggested outcomes. Clinicians may enhance engagement by investing time and energy in the growth and development of the therapeutic relationship with clients, as this is paramount to maintaining clients' investment in continuing therapy and also may act as a driver of neuroplastic changes. PMID:22544406

  9. Information Presentation

    NASA Technical Reports Server (NTRS)

    Holden, K.L.; Boyer, J.L.; Sandor, A.; Thompson, S.G.; McCann, R.S.; Begault, D.R.; Adelstein, B.D.; Beutter, B.R.; Stone, L.S.

    2009-01-01

    The goal of the Information Presentation Directed Research Project (DRP) is to address design questions related to the presentation of information to the crew. The major areas of work, or subtasks, within this DRP are: 1) Displays, 2) Controls, 3) Electronic Procedures and Fault Management, and 4) Human Performance Modeling. This DRP is a collaborative effort between researchers at Johnson Space Center and Ames Research Center.

  10. Principles of nanoscience: an overview.

    PubMed

    Behari, Jitendra

    2010-10-01

    The scientific basis of nanotechnology as envisaged from the first principles is compared to bulk behavior. Development of nanoparticles having controllable physical and electronic properties has opened up possibility of designing artificial solids. Top down and bottom up approaches are emphasized. The role of nanoparticle (quantum dots) application in nanophotonics (photovoltaic cell), and drug delivery vehicle is discussed. Fundamentals of DNA structure as the prime site in bionanotechnological manipulations is also discussed. A summary of presently available devices and applications are presented. PMID:21299044

  11. Spaceborne receivers: Basic principles

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.

    1984-01-01

    The underlying principles of operation of microwave receivers for space observations of planetary surfaces were examined. The design philosophy of the receiver as it is applied to operate functionally as an efficient receiving system, the principle of operation of the key components of the receiver, and the important differences among receiver types are explained. The operating performance and the sensitivity expectations for both the modulated and total power receiver configurations are outlined. The expressions are derived from first principles and are developed through the important intermediate stages to form practicle and easily applied equations. The transfer of thermodynamic energy from point to point within the receiver is illustrated. The language of microwave receivers is applied statistics.

  12. Enhanced visible-light photocatalytic activity of a g-C3N4/BiVO4 nanocomposite: a first-principles study.

    PubMed

    Zhang, Jihua; Ren, Fengzhu; Deng, Mingsen; Wang, Yuanxu

    2015-04-21

    The structural, electronic, and optical properties of a g-C3N4(001)/BiVO4(010) nanocomposite have been investigated using first-principles calculations. The results indicate that g-C3N4(001) can stably adsorb onto the BiVO4(010) surface, and it tends to form a regular wavy shape. The calculated band gap of the g-C3N4(001)/BiVO4(010) nanocomposite is narrower compared with that of BiVO4 or BiVO4(010), primarily due to the introduction of N 2p states near the Fermi level. The g-C3N4(001)/BiVO4(010) nanocomposite has a favorable type-II band alignment; thus, photoexcited electrons can be injected into the conduction band of g-C3N4(001) from the conduction band of BiVO4(010). The proper interface charge distribution facilitates carrier separation in the g-C3N4(001)/BiVO4(010) interface region. The electron injection and carrier separation can prevent the recombination of electron-hole pairs. The calculated absorption coefficients indicate an obvious redshift of the absorption edge, which is in good agreement with the experimental results. Our calculation results suggest that the g-C3N4(001)/BiVO4(010) nanocomposite has significant advantages for visible-light photocatalysis. PMID:25798459

  13. Activity.

    ERIC Educational Resources Information Center

    Clearing: Nature and Learning in the Pacific Northwest, 1984

    1984-01-01

    Presents three activities: (1) investigating succession in a schoolground; (2) investigating oak galls; and (3) making sun prints (photographs made without camera or darkroom). Each activity includes a list of materials needed and procedures used. (JN)

  14. [Principle of the activity-controlled rate-adaptive cardiac pacemaker: analysis of stress and environment-induced mechanical effects on the human body].

    PubMed

    Alt, E; Matula, M; Theres, H; Heinz, M

    1989-09-01

    Rate-adaptive pacemakers are increasingly becoming part of clinical routine, the most widespread systems being activity-controlled. In order to shed more light on the foundations of mechanical forces which can possibly be utilized for controlling rate-adaptive systems, we conducted tests on six healthy volunteers and six pacemaker patients. With the aid of three orthogonal wide-band linear acceleration pick-ups attached to the body, the mechanical signals were recorded from the three axes during different activities. Along with standardized exercise on bicycle and treadmill ergometers, we tested the influence of household activities and interference influences. The results were analyzed in terms of the amplitude and frequency content of the signals. For walking activities we found a signal amplitude increasing in largely linear fashion with the walking speed, the signal amplitudes being approximately twice as high on the vertical axis as on the other two axes. Exercise on the bicycle ergometer produced mechanical signals of clearly lower amplitude than comparable walking activities. The Fast-Fourier analysis showed amplitude peaks in the low frequency range of 1 to 4 Hz for all forms of physiological exercise, while interference influences showed amplitude peaks mainly in the range above 8 Hz. The use of an acceleration pickup and a corresponding low pass filter might be a way of reducing the effect of nonphysiological interference influences on an activity-controlled pacemaker system. A sensor measuring in the horizontal axis appears to be the most favorable compromise for the various types of exercise. However, due to the considerable difference in signal amplitude for different types of exercise of the same intensity, an activity-controlled pacemaker system cannot entirely meet metabolic conditions and requirements. PMID:2815913

  15. Processing and MHC class II presentation of exogenous soluble antigen involving a proteasome-dependent cytosolic pathway in CD40-activated B cells.

    PubMed

    Becker, Hans Jiro; Kondo, Eisei; Shimabukuro-Vornhagen, Alexander; Theurich, Sebastian; von Bergwelt-Baildon, Michael S

    2016-08-01

    Activated B cells have the capacity to present antigen and induce immune responses as potent antigen-presenting cells (APCs). As in other APCs, antigen presentation by B cells involves antigen internalization, antigen processing, and peptide loading onto MHC molecules. However, while the mechanism of antigen processing has been studied extensively in other APCs, this pathway remains elusive in B cells. The aim of this study was to investigate the MHC class II processing pathway in CD40-activated B cells (CD40Bs), as a model for activated, antigen-presenting B cells. Using CMV pp65 as a model antigen, we evaluated processing and presentation of the CD4 + T-cell epitope 509-523 (K509) by human CD40Bs in ELISPOT assays. As expected, stimulation of specific CD4 + T-cell clones was attenuated after pretreatment of CD40Bs with inhibitors of classic class II pathway components. However, proteasome inhibitors such as epoxomicin limited antigen presentation as well. This suggests that the antigen is processed in a non-classical, cytosolic MHC class II pathway. Further experiments with truncated protein variants revealed involvement of the proteasome in processing of the N and C extensions of the epitope. Access to the cytosol was shown to be size dependent. Epoxomicin sensitivity exclusively in CD40B cells, but not in dendritic cells, suggests a novel processing mechanism unique to this APC. Our data suggest that B cells process antigen using a distinct, non-classical class II pathway. PMID:26561366

  16. Teaching/learning principles

    NASA Technical Reports Server (NTRS)

    Hankins, D. B.; Wake, W. H.

    1981-01-01

    The potential remote sensing user community is enormous, and the teaching and training tasks are even larger; however, some underlying principles may be synthesized and applied at all levels from elementary school children to sophisticated and knowledgeable adults. The basic rules applying to each of the six major elements of any training course and the underlying principle involved in each rule are summarized. The six identified major elements are: (1) field sites for problems and practice; (2) lectures and inside study; (3) learning materials and resources (the kit); (4) the field experience; (5) laboratory sessions; and (6) testing and evaluation.

  17. Itch Management: General Principles.

    PubMed

    Misery, Laurent

    2016-01-01

    Like pain, itch is a challenging condition that needs to be managed. Within this setting, the first principle of itch management is to get an appropriate diagnosis to perform an etiology-oriented therapy. In several cases it is not possible to treat the cause, the etiology is undetermined, there are several causes, or the etiological treatment is not effective enough to alleviate itch completely. This is also why there is need for symptomatic treatment. In all patients, psychological support and associated pragmatic measures might be helpful. General principles and guidelines are required, yet patient-centered individual care remains fundamental. PMID:27578069

  18. Structure-Activity Analysis of the Dermcidin-derived Peptide DCD-1L, an Anionic Antimicrobial Peptide Present in Human Sweat*

    PubMed Central

    Paulmann, Maren; Arnold, Thomas; Linke, Dirk; Özdirekcan, Suat; Kopp, Annika; Gutsmann, Thomas; Kalbacher, Hubert; Wanke, Ines; Schuenemann, Verena J.; Habeck, Michael; Bürck, Jochen; Ulrich, Anne S.; Schittek, Birgit

    2012-01-01

    Dermcidin encodes the anionic amphiphilic peptide DCD-1L, which displays a broad spectrum of antimicrobial activity under conditions resembling those in human sweat. Here, we have investigated its mode of antimicrobial activity. We found that DCD-1L interacts preferentially with negatively charged bacterial phospholipids with a helix axis that is aligned flat on a lipid bilayer surface. Upon interaction with lipid bilayers DCD-1L forms oligomeric complexes that are stabilized by Zn2+. DCD-1L is able to form ion channels in the bacterial membrane, and we propose that Zn2+-induced self-assembly of DCD-1L upon interaction with bacterial lipid bilayers is a prerequisite for ion channel formation. These data allow us for the first time to propose a molecular model for the antimicrobial mechanism of a naturally processed human anionic peptide that is active under the harsh conditions present in human sweat. PMID:22262861

  19. Identification of Proteins with Potential Osteogenic Activity Present in the Water-Soluble Matrix Proteins from Crassostrea gigas Nacre Using a Proteomic Approach

    PubMed Central

    Oliveira, Daniel V.; Silva, Tomé S.; Cordeiro, Odete D.; Cavaco, Sofia I.; Simes, Dina C.

    2012-01-01

    Nacre, when implanted in vivo in bones of dogs, sheep, mice, and humans, induces a biological response that includes integration and osteogenic activity on the host tissue that seems to be activated by a set of proteins present in the nacre water-soluble matrix (WSM). We describe here an experimental approach that can accurately identify the proteins present in the WSM of shell mollusk nacre. Four proteins (three gigasin-2 isoforms and a cystatin A2) were for the first time identified in WSM of Crassostrea gigas nacre using 2DE and LC-MS/MS for protein identification. These proteins are thought to be involved in bone remodeling processes and could be responsible for the biocompatibility shown between bone and nacre grafts. These results represent a contribution to the study of shell biomineralization process and opens new perspectives for the development of new nacre biomaterials for orthopedic applications. PMID:22666151

  20. Analysis of expression and inhibitory activity of a TrcC-6 phytocystatin present in developing and germinating seeds of triticale (×Triticosecale Wittm.).

    PubMed

    Simińska, Joanna; Orzechowski, Sławomir; Bielawski, Wiesław

    2015-11-01

    Storage proteins of cereal seeds are processed during accumulation and degraded during germination primarily by cysteine proteinases. One of the mechanisms controlling the activity of these enzymes is the synthesis of specific inhibitors named phytocystatins. Here we present the complete gene sequence of a triticale ( × Triticosecale Wittm.) phytocystatin, TrcC-6, which encodes a 152-amino acid protein with a putative 25-amino acid signal peptide. This protein has a calculated molecular mass of 16.2 kDa, and was assigned to phylogenetic group B of phytocystatins. Because TrcC-6 transcripts are present in triticale seeds, we hypothesized that this phytocystatin regulates storage protein accumulation and degradation. Therefore, changes in gene expression during the entire period of seed development and germination were examined. TrcC-6 transcripts and TrcC-6 protein levels increased during the maturation of seeds and remained high during the first hours of germination. This enabled us to conclude that TrcC-6 likely regulates seed germination by the regulation of storage protein hydrolysis. For the analysis of TrcC-6 inhibitory activity, recombinant protein was expressed in Escherichia coli BL21 (DE3) and purified. Recombinant TrcC-6 proved to be a potent inhibitor of cysteine proteinases. It inhibited the in vitro activity of papain (EC 3.4.22.2) and ficin (EC 3.4.22.3). Furthermore, native PAGE analysis revealed that recombinant TrcC-6 inhibits the activity of endogenous cysteine proteinases present in germinating seeds of triticale. Based on these results, TrcC-6 is likely one of the important factors that regulate cysteine proteinase activity during the accumulation and mobilization of storage proteins. PMID:26298807

  1. The effect of stable macromolecular complexes of ionic polyphosphazene on HIV Gag antigen and on activation of human dendritic cells and presentation to T-cells.

    PubMed

    Palmer, Christine D; Ninković, Jana; Prokopowicz, Zofia M; Mancuso, Christy J; Marin, Alexander; Andrianov, Alexander K; Dowling, David J; Levy, Ofer

    2014-10-01

    Neonates and infants are susceptible to infection due to distinct immune responses in early life. Therefore, development of vaccine formulation and delivery systems capable of activating human newborn leukocytes is of global health importance. Poly[di(carboxylatophenoxy)phosphazene] (PCPP) belongs to a family of ionic synthetic polyphosphazene polyelectrolyte compounds that can form non-covalent interactions with protein antigens and demonstrate adjuvant activity in animals and in human clinical trials. However, little is known about their ability to activate human immune cells. In this study, we characterized the effects of PCPP alone or in combination with a model antigen (recombinant HIV-Gag (Gag)), on the maturation, activation and antigen presentation by human adult and newborn dendritic cells (DCs) in vitro. PCPP treatment induced DC activation as assessed by upregulation of co-stimulatory molecules and cytokine production. Studies benchmarking PCPP to Alum, the most commonly used vaccine adjuvant, demonstrated that both triggered cell death and release of danger signals in adult and newborn DCs. When complexed with Gag antigen, PCPP maintained its immunostimulatory characteristics while permitting internalization and presentation of Gag by DCs to HIV-Gag-specific CD4(+) T cell clones. The PCPP vaccine formulation outlined here has intrinsic adjuvant activity, can facilitate effective delivery of antigen to DCs, and may be advantageous for induction of beneficial T cell-mediated immunity. Moreover, polyphosphazenes can further reduce cost of vaccine production and distribution through their dose-sparing and antigen-stabilizing properties, thus potentially eliminating the need for cold chain distribution. PMID:25023392

  2. Matching the Neurobiology of Learning to Teaching Principles

    ERIC Educational Resources Information Center

    Moffett, Nelle; Fleisher, Steven C.

    2013-01-01

    The authors describe principles of good teaching drawn from meta-analyses of research on teaching effectiveness. Recent developments in neurobiology are presented and aligned to provide biological support for these principles. To make it easier for college faculty to try out sample instructional strategies, the authors map principles of good…

  3. Action Research and Narrative Inquiry: Five Principles for Validation Revisited

    ERIC Educational Resources Information Center

    Heikkinen, Hannu L. T.; Huttunen, Rauno; Syrjala, Leena; Pesonen, Jyri

    2012-01-01

    The article continues the discussion of the five quality principles proposed by Heikkinen, Huttunen, and Syrjala, published in 2007 in "Educational Action Research". In the present article, the authors reconsider the five principles: historical continuity; reflexivity; dialectics; workability; and evocativeness. These five principles are…

  4. [Scientific presentation].

    PubMed

    Kraft, Giuliano

    2002-01-01

    To give a correct and effective scientific presentation, is an arduous task that asks for close examination of basic techniques of communication. This article proposes indications and suggestions to help public speakers to be communicators, to use visual aids and it explains how to capture the audience attention. PMID:12599721

  5. A First-Principle Study of Synergized O2 Activation and CO Oxidation by Ag Nanoparticles on TiO2(101) Support.

    PubMed

    Jia, Chuanyi; Zhang, Guozhen; Zhong, Wenhui; Jiang, Jun

    2016-04-27

    We performed density functional theory (DFT) calculations to investigate the synergized O2 activation and CO oxidation by Ag8 cluster on TiO2(101) support. The excellent catalytic activity of the interfacial Ag atoms in O2 dissociation is ascribed to the positive polarized charges, upshift of Ag d-band center, and assistance of surface Ti5c atoms. CO oxidation then takes place via a two-step mechanism coupled with O2 dissociation: (i) CO + O2 → CO2 + O and (ii) CO + O → CO2. The synergistic effect of CO and O2 activations reduces the oxidation energy barrier (Ea) of reaction (i), especially for the up-layered Ag atoms not in contact with support. It is found that the coadsorbed CO and O2 on the up-layered Ag atoms form a metal-stable four-center O-O-CO structure motif substantially promoting CO oxidation. On the oxygen defective Ag8/TiO2(101) surface, because of the decreased positive charges and the down-shift of d-band centers in Ag, the metal cluster exhibits low O2 adsorption and activation abilities. Although the dissociation of O2 is facilitated by the TiO2(101) defect sites, the dissociated O atoms would cover the defects so strongly that further CO oxidation would be prohibited unless much extra energy is introduced to recreate oxygen defects. PMID:27049335

  6. Increase in a distinct pulmonary macrophage subset possessing an antigen-presenting cell phenotype and in vitro APC activity following silica exposure

    SciTech Connect

    Migliaccio, Christopher T. . E-mail: christopher.migliaccio@umontana.edu; Hamilton, Raymond F.; Holian, Andrij

    2005-06-01

    Silica inhalation results in chronic lung inflammation and fibrosis. While the role of the alveolar macrophage (AM) is considered key to the effects of silica on lung pathology, the etiology is not completely understood. Evidence suggests an increase in antigen presenting cell (APC) activity as a contributing factor to this process, as well as potential roles for both AM and interstitial macrophages (IM) in silicosis. In order to study the effects of crystalline silica on the APC activity of pulmonary macrophages, mice were exposed intranasally and changes in pulmonary macrophage populations were assessed using flow cytometry. Following intranasal instillation of silica, a significant increase in the APC activity of AM was observed, as well as a significant increase in a subset of IM expressing classic APC markers (MHC class II, CD11c). In addition, an in vitro system using bone marrow-derived macrophages (BMDM) was generated to assess the effects of silica on the APC activity of macrophages in vitro. Data using BMDM in the in vitro APC assay demonstrated a significant increase in APC activity following silica exposure, but not following exposure to saline or a control particle (TiO{sub 2}). Using a combination of in vivo and in vitro experiments, the current study describes a significant increase in an interstitial macrophage subset with an APC phenotype, as well as an increase in the APC activity of both AM and BMDM, as a direct result of exposure to crystalline silica. These studies suggest a specific mechanism, macrophage subset activation, by which crystalline silica exposure results in chronic pulmonary inflammation and, eventually, fibrosis.

  7. Overview Presentation

    NASA Technical Reports Server (NTRS)

    Lytle, John

    2001-01-01

    This report provides an overview presentation of the 2000 NPSS (Numerical Propulsion System Simulation) Review and Planning Meeting. Topics include: 1) a background of the program; 2) 1999 Industry Feedback; 3) FY00 Status, including resource distribution and major accomplishments; 4) FY01 Major Milestones; and 5) Future direction for the program. Specifically, simulation environment/production software and NPSS CORBA Security Development are discussed.

  8. The Idiom Principle Revisited

    ERIC Educational Resources Information Center

    Siyanova-Chanturia, Anna; Martinez, Ron

    2015-01-01

    John Sinclair's Idiom Principle famously posited that most texts are largely composed of multi-word expressions that "constitute single choices" in the mental lexicon. At the time that assertion was made, little actual psycholinguistic evidence existed in support of that holistic, "single choice," view of formulaic language. In…

  9. Reprographic Principles Made Easy.

    ERIC Educational Resources Information Center

    Young, J. B.

    Means for reproducing graphic materials are explained. There are several types of processes: those using light sensitive material, those using heat sensitive material, those using photo conductive materials (electrophotography), and duplicating processes using ink. For each of these, the principles behind them are explained, the necessary…

  10. PRINCIPLES OF WATER FILTRATION

    EPA Science Inventory

    This paper reviews principles involved in the processes commonly used to filter drinking water for public water systems. he most common approach is to chemically pretreat water and filter it through a deep (2-1/2 to 3 ft) bed of granuu1ar media (coal or sand or combinations of th...

  11. Extended Mach Principle.

    ERIC Educational Resources Information Center

    Rosen, Joe

    1981-01-01

    Discusses the meaning of symmetry of the laws of physics and symmetry of the universe and the connection between symmetries and asymmetries of the laws of physics and those of the universe. An explanation of Hamilton's principle is offered. The material is suitable for informal discussions with students. (Author/SK)

  12. Matters of Principle.

    ERIC Educational Resources Information Center

    Martz, Carlton

    1999-01-01

    This issue of "Bill of Rights in Action" looks at individuals who have stood on principle against authority or popular opinion. The first article investigates John Adams and his defense of British soldiers at the Boston Massacre trials. The second article explores Archbishop Thomas Becket's fatal conflict with England's King Henry II. The final…

  13. Antigen-induced regulation of T-cell motility, interaction with antigen-presenting cells and activation through endogenous thrombospondin-1 and its receptors

    PubMed Central

    Bergström, Sten-Erik; Uzunel, Mehmet; Talme, Toomas; Bergdahl, Eva; Sundqvist, Karl-Gösta

    2015-01-01

    Antigen recognition reduces T-cell motility, and induces prolonged contact with antigen-presenting cells and activation through mechanisms that remain unclear. Here we show that the T-cell receptor (TCR) and CD28 regulate T-cell motility, contact with antigen-presenting cells and activation through endogenous thrombospondin-1 (TSP-1) and its receptors low-density lipoprotein receptor-related protein 1 (LRP1), calreticulin and CD47. Antigen stimulation induced a prominent up-regulation of TSP-1 expression, and transiently increased and subsequently decreased LRP1 expression whereas calreticulin was unaffected. This antigen-induced TSP-1/LRP1 response down-regulated a motogenic mechanism directed by LRP1-mediated processing of TSP-1 in cis within the same plasma membrane while promoting contact with antigen-presenting cells and activation through cis interaction of the C-terminal domain of TSP-1 with CD47 in response to N-terminal TSP-1 triggering by calreticulin. The antigen-induced TSP-1/LRP1 response maintained a reduced but significant motility level in activated cells. Blocking CD28 co-stimulation abrogated LRP1 and TSP-1 expression and motility. TCR/CD3 ligation alone enhanced TSP-1 expression whereas CD28 ligation alone enhanced LRP1 expression. Silencing of TSP-1 inhibited T-cell conjugation to antigen-presenting cells and T helper type 1 (Th1) and Th2 cytokine responses. The Th1 response enhanced motility and increased TSP-1 expression through interleukin-2, whereas the Th2 response weakened motility and reduced LRP1 expression through interleukin-4. Ligation of the TCR and CD28 therefore elicits a TSP-1/LRP1 response that stimulates prolonged contact with antigen-presenting cells and, although down-regulating motility, maintains a significant motility level to allow serial contacts and activation. Th1 and Th2 cytokine responses differentially regulate T-cell expression of TSP-1 and LRP1 and motility. PMID:25393517

  14. Influence of Agathi grandiflora active principles inhibit viral multiplication and stimulate immune system in Indian white shrimp Fenneropenaeus indicus against white spot syndrome virus infection.

    PubMed

    Bindhu, Francis; Velmurugan, Subramanian; Donio, Mariathason Birdilla Selva; Michaelbabu, Mariavincent; Citarasu, Thavasimuthu

    2014-12-01

    Five herbs including Adathoda vasica, Agathi grandiflora, Leucas aspera, Psoralea corylifolia, and Quercus infectoria were selected to screen the antiviral and immunostimulant activity against white spot syndrome virus (WSSV) and Vibrio harveyi respectively using different organic polar and non-polar solvents. Based on the initial screening results, ethyl acetate and methanolic extracts of A. grandiflora had strong antiviral and immunostimulant activities. Those extracts incubated with WSSV injected Fenneropenaeus indicus got only 20% mortality and no PCR positive signals were seen in two step PCR amplification. The methanolic extracts of A. grandiflora were further purified through silica column chromatography and the fractions screened again for antiviral and immunostimulant activity. The secondary screening results revealed that, the fractions of F5 to F7 had effectively controlled the WSSV multiplication and V. harveyi growth. The pooled fractions (F5 to F7) was structurally characterized by gas chromatograph-mass spectrometry (GC-MS) analysis and few compounds were identified including 3,7.11,15-Tetramethyl-2-Hexane-1-ol, pytol and 1,2-Benzenedicarboxylic acid, diisooctyl ester. The pooled fractions were mixed with the basal feed ingredients at the concentration of 100 (D-1), 200 (D-2), 300 (D-3) and 400 (D-4) mg kg(-1) and the diets fed to the F. indicus (9.0 ± 0.5 g) for 30 days. After the completion of feeding trail, they were challenged with virulent WSSV and studied the cumulative mortality, molecular diagnosis by quantitative real time PCR (qRT-PCR), biochemical, haematological and immunological parameters. The control diet fed F. indicus succumbed to death 100% within 3 days whereas the D-3 and D-4 helped to reduced the cumulative mortality of 60-80% respectively. The qRT-PCR revealed that, the WSSV copy number was gradually decreased when increasing concentration of A. grandiflora extract active fraction in the diets. The diets D-3 and D-4 helped to

  15. Multi-Target QSAR Approaches for Modeling Protein Inhibitors. Simultaneous Prediction of Activities Against Biomacromolecules Present in Gram-Negative Bacteria.

    PubMed

    Speck-Planche, Alejandro; Cordeiro, M N D S

    2015-01-01

    Drug discovery is aimed at finding therapeutic agents for the treatment of many diverse diseases and infections. However, this is a very slow an expensive process, and for this reason, in silico approaches are needed to rationalize the search for new molecular entities with desired biological profiles. Models focused on quantitative structure-activity relationships (QSAR) have constituted useful complementary tools in medicinal chemistry, allowing the virtual predictions of dissimilar pharmacological activities of compounds. In the last 10 years, multi-target (mt) QSAR models have been reported, representing great advances with respect to those models generated from classical approaches. Thus, mt- QSAR models can simultaneously predict activities against different biological targets (proteins, microorganisms, cell lines, etc.) by using large and heterogeneous datasets of chemicals. The present review is devoted to discuss the most promising mt-QSAR models, particularly those developed for the prediction of protein inhibitors. We also report the first multi-tasking QSAR (mtk-QSAR) model for simultaneous prediction of inhibitors against biomacromolecules (specifically proteins) present in Gram-negative bacteria. This model allowed us to consider both different proteins and multiple experimental conditions under which the inhibitory activities of the chemicals were determined. The mtk-QSAR model exhibited accuracies higher than 98% in both training and prediction sets, also displaying a very good performance in the classification of active and inactive cases that depended on the specific elements of the experimental conditions. The physicochemical interpretations of the molecular descriptors were also analyzed, providing important insights regarding the molecular patterns associated with the appearance/enhancement of the inhibitory potency. PMID:25961517

  16. Mapping whole-brain activity with cellular resolution by light-sheet microscopy and high-throughput image analysis (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Silvestri, Ludovico; Rudinskiy, Nikita; Paciscopi, Marco; Müllenbroich, Marie Caroline; Costantini, Irene; Sacconi, Leonardo; Frasconi, Paolo; Hyman, Bradley T.; Pavone, Francesco S.

    2016-03-01

    Mapping neuronal activity patterns across the whole brain with cellular resolution is a challenging task for state-of-the-art imaging methods. Indeed, despite a number of technological efforts, quantitative cellular-resolution activation maps of the whole brain have not yet been obtained. Many techniques are limited by coarse resolution or by a narrow field of view. High-throughput imaging methods, such as light sheet microscopy, can be used to image large specimens with high resolution and in reasonable times. However, the bottleneck is then moved from image acquisition to image analysis, since many TeraBytes of data have to be processed to extract meaningful information. Here, we present a full experimental pipeline to quantify neuronal activity in the entire mouse brain with cellular resolution, based on a combination of genetics, optics and computer science. We used a transgenic mouse strain (Arc-dVenus mouse) in which neurons which have been active in the last hours before brain fixation are fluorescently labelled. Samples were cleared with CLARITY and imaged with a custom-made confocal light sheet microscope. To perform an automatic localization of fluorescent cells on the large images produced, we used a novel computational approach called semantic deconvolution. The combined approach presented here allows quantifying the amount of Arc-expressing neurons throughout the whole mouse brain. When applied to cohorts of mice subject to different stimuli and/or environmental conditions, this method helps finding correlations in activity between different neuronal populations, opening the possibility to infer a sort of brain-wide 'functional connectivity' with cellular resolution.

  17. Teaching Principles of One-Way Analysis of Variance Using M&M's Candy

    ERIC Educational Resources Information Center

    Schwartz, Todd A.

    2013-01-01

    I present an active learning classroom exercise illustrating essential principles of one-way analysis of variance (ANOVA) methods. The exercise is easily conducted by the instructor and is instructive (as well as enjoyable) for the students. This is conducive for demonstrating many theoretical and practical issues related to ANOVA and lends itself…

  18. Application of the Total Quality Management Approach Principles and the ISO 9000 Standards in Engineering Education.

    ERIC Educational Resources Information Center

    Waks, Shlomo; Frank, Moti

    1999-01-01

    Discusses the applicability of the definition, principles, and underlying strategies of total quality management (TQM) for engineering education. Describes several tools and methods for the implementation of TQM and its suitability for a variety of school activities. Presents a TQM course outline combining lectures, discussions, suggested…

  19. Anti-inflammatory effects of the partially purified extract of radix Stephaniae tetrandrae: comparative studies of its active principles tetrandrine and fangchinoline on human polymorphonuclear leukocyte functions.

    PubMed

    Shen, Y C; Chou, C J; Chiou, W F; Chen, C F

    2001-11-01

    We hypothesized that prevention of neutrophil from activation may underlie the myocardial protective effect of the specially processed extract of radix Stephaniae tetrandrae (SPRST). Inflammatory responses in isolated peripheral human neutrophils were studied in the presence or absence of SPRST. SPRST (1-10 microg/ml) concentration-dependently prevented N-formyl-methionyl-leucyl-phenylalanine (fMLP)- or leukotriene B(4) (LTB(4))-induced neutrophil adhesion and transmigration. Comparable results were also observed in neutrophils pretreated with fangchinoline (Fan) or tetrandrine (Tet), two active components in SPRST. It has been reported that neutrophil adhesion/transmigration is mainly Mac-1 (CD11b/CD18)-dependent and could be modulated by reactive oxygen species (ROS) production. SPRST, Tet, and Fan diminished fMLP- or LTB4-induced Mac-1 up-regulation and ROS production. SPRST, Fan, Tet, and verapamil impaired fMLP-induced rapid intracellular alkalization, an essential mechanism for neutrophil ROS production, and [Ca(2+)](i) increment, suggesting that a calcium dependent pathway might be involved. Direct G protein activation by AlF(4)(-) also triggered [Ca(2+)](i) increment and adhesion that could be abolished by pertussis toxin and were partially reversed by SPRST, Fan, and Tet. These results reveal that inhibition of neutrophil adhesion and transmigration may account for SPRST's myocardial protective effect. This effect of SPRST may be mediated by component(s) in addition to Tet and Fan because combination of 0.1 microg/ml of Tet and Fan did not mimic the effect of SPRST. We conclude that SPRST exerts anti-inflammatory effects by interfering with ROS production and Ca(2+) influx through G protein modulation to prevent Mac-1 up-regulation in neutrophil activation. PMID:11641437

  20. A Neoglycoconjugate Containing the Human Milk Sugar LNFPIII Drives Anti-Inflammatory Activation of Antigen Presenting Cells in a CD14 Dependent Pathway

    PubMed Central

    Tundup, Smanla; Srivastava, Leena; Norberg, Thomas; Watford, Wendy; Harn, Donald

    2015-01-01

    The milk pentasaccharide LNFPIII has therapeutic action for metabolic and autoimmune diseases and prolongs transplant survival in mice when presented as a neoglycoconjugate. Within LNFPIII is the Lewisx trisaccharide, expressed by many helminth parasites. In humans, LNFPIII is found in human milk and also known as stage-specific embryonic antigen-1. LNFPIII-NGC drives alternative activation of macrophages and dendritic cells via NFκB activation in a TLR4 dependent mechanism. However, the connection between LNFPIII-NGC activation of APCs, TLR4 signaling and subsequent MAP kinase signaling leading to anti-inflammatory activation of APCs remains unknown. In this study we determined that the innate receptor CD14 was essential for LNFPIII-NGC induction of both ERK and NFkB activation in APCs. Induction of ERK activation by LNFPIII-NGC was completely dependent on CD14/TLR4-Ras-Raf1/TPL2-MEK axis in bone marrow derived dendritic cells (BMDCs). In addition, LNFPIII-NGC preferentially induced the production of Th2 “favoring” chemokines CCL22 and matrix metalloprotease protein-9 in a CD14 dependent manner in BMDCs. In contrast, LNFPIII-NGC induces significantly lower levels of Th1 “favoring” chemokines, MIP1α, MIP1β and MIP-2 compared to levels in LPS stimulated cells. Interestingly, NGC of the identical human milk sugar LNnT, minus the alpha 1–3 linked fucose, failed to activate APCs via TLR4/MD2/CD14 receptor complex, suggesting that the alpha 1–3 linked fucose in LNFPIII and not on LNnT, is required for this process. Using specific chemical inhibitors of the MAPK pathway, we found that LNFPIII-NGC induction of CCL22, MMP9 and IL-10 production was dependent on ERK activation. Over all, this study suggests that LNFPIII-NGC utilizes CD14/TLR4-MAPK (ERK) axis in modulating APC activation to produce anti-inflammatory chemokines and cytokines in a manner distinct from that seen for the pro-inflammatory PAMP LPS. These pathways may explain the in vivo therapeutic

  1. Heightened Vagal Activity during High-Calorie Food Presentation in Obese compared with Non-obese Individuals - Results of a Pilot Study

    PubMed Central

    Udo, Tomoko; Weinberger, Andrea H.; Grilo, Carlos M.; Brownell, Kelly D.; DiLeone, Ralph J.; Lampert, Rachel; Matlin, Samantha L.; Yanagisawa, Katherine; McKee, Sherry A.

    2013-01-01

    Summary Eating behaviors are highly cue-dependent. Changes in mood states and exposure to palatable food both increase craving and consumption of food. Vagal activity supports adaptive modulation of physiological arousal and has an important role in cue-induced appetitive behaviors. Using high-frequency heart rate variability (HF HRV), this preliminary study compared vagal activity during positive and negative mood induction, and presentation of preferred high-calorie food items between obese (n = 12; BMI ≥ 30) and non-obese individuals (n = 14; 18.5 < BMI < 30). Participants completed two laboratory sessions (negative vs. positive mood conditions). Following 3-hours of food deprivation, all participants completed a mood induction, and then were exposed to their preferred high-calorie food items. HF HRV was assessed throughout. Obese and non-obese individuals were not significantly different in HF HRV during positive or negative mood induction. Obese individuals showed significantly greater levels of HF HRV during presentation of their preferred high-calorie food items than non-obese individuals, particularly in the positive mood condition. This is the first study to demonstrate increased vagal activity in response to food cues in obese individuals compared with non-obese individuals. Our findings warrant further investigation on the potential role of vagally-mediated cue reactivity in overeating and obesity. PMID:24847667

  2. Patterns and Principles for Blended Synchronous Learning: Engaging Remote and Face-to-Face Learners in Rich-Media Real-Time Collaborative Activities

    ERIC Educational Resources Information Center

    Bower, Matt; Kenney, Jacqueline; Dalgarno, Barney; Lee, Mark J. W.; Kennedy, Gregor E.

    2014-01-01

    Blended synchronous learning involves using rich-media technologies to enable remote and face-to-face students to jointly participate in the same live classes. This article presents blended synchronous learning designs from seven case studies that were part of a project funded by the Australian Government Office for Learning and Teaching and…

  3. On the active principles of the spurge family, X. Skin irritants, cocarcinogens, and cryptic cocarcinogens from the latex of the manchineel tree.

    PubMed

    Adolf, W; Hecker, E

    1984-01-01

    From the hydrophobic fraction of the latex of Hippomane mancinella, weak or nonirritant mixtures of esters of polyfunctional diterpene parent alcohols of the tigliane and daphnane types were isolated belonging to the structural type of "cryptic" irritants. The cryptic factor group M'z (tigliane type) represents 12-deoxyphorbol-13,20-diesters, and the cryptic factor groups M'y and M'x (daphnane type) represent mixtures of 9,13,14-orthoesters-20-esters of resiniferonol and 5 beta-hydroxyresiniferonol-6 alpha,7 alpha-oxide, respectively. All of them carry in the 20-position homologous long-chain fatty acids, ranging from C15 to C26. They may be "activated" by mild transesterification reactions yielding corresponding irritant factor groups with free hydroxyl functions at C-20. From the hydrophilic fraction of the latex, the irritant factor M3 (tigliane type) and the factor group Mx (daphnane type) were isolated. According to spectral data, factor M3 represents the 13-(hexadeca-2,4,6-trienoic acid) ester of the parent 12-deoxy-5 beta-hydroxyphorbol-6 alpha,7 alpha-oxide. Factor group Mx consists of two esters inseparable by tlc (silica gel). One is identical with huratoxin; the other represents a hexadeca-2,4,6-trienoic acid orthoester. Mx is also obtained by transesterification of M'x and exhibits irritant and tumor-promoting activity comparable to that of TPA. Some aspects on structure activity relations are deduced from selected chemical-reaction products of factor group Mx. PMID:6481361

  4. Anthrax lethal toxin impairs CD1d-mediated antigen presentation by targeting the extracellular signal-related kinase 1/2 mitogen-activated protein kinase pathway.

    PubMed

    Khan, Masood A; Gallo, Richard M; Brutkiewicz, Randy R

    2010-05-01

    Lethal toxin (LT) is a critical virulence factor of Bacillus anthracis and an important means by which this bacterium evades the host's immune system. In this study, we demonstrate that CD1d-expressing cells treated with LT have reduced CD1d-mediated antigen presentation. We earlier showed an important role for the mitogen-activated protein kinase extracellular signal-regulated kinase 1/2 (ERK1/2) in the regulation of CD1d-mediated antigen presentation, and we report here that LT impairs antigen presentation by CD1d in an ERK1/2-dependent manner. Similarly, LT and the ERK1/2 pathway-specific inhibitor U0126 caused a decrease in major histocompatibility complex (MHC) class II-mediated antigen presentation. Confocal microscopy analyses revealed altered intracellular distribution of CD1d and LAMP-1 in LT-treated cells, similar to the case for ERK1/2-inhibited cells. These results suggest that Bacillus anthracis has the ability to evade the host's innate immune system by reducing CD1d-mediated antigen presentation through targeting the ERK1/2 pathway. PMID:20194602

  5. Immunomodulatory Glycan Lacto-N-Fucopentaose III Requires Clathrin-Mediated Endocytosis To Induce Alternative Activation of Antigen-Presenting Cells

    PubMed Central

    Srivastava, Leena; Tundup, Smanla; Choi, Beak-San; Norberg, Thomas

    2014-01-01

    The mechanism of alternative activation of antigen-presenting cells (APCs) is largely unknown. Lacto-N-fucopentaose III (LNFPIII) is a biologically conserved pentasaccharide that contains the Lewisx trisaccharide. LNFPIII conjugates and schistosome egg antigens, which contain the Lewisx trisaccharide, drive alternative activation of APCs and induce anti-inflammatory responses in vivo, preventing inflammation-based diseases, including psoriasis, transplant organ rejection, and metabolic disease. In this study, we show that LNFPIII conjugates and schistosome egg antigens interact with APCs via a receptor-mediated process, requiring internalization of these molecules through a clathrin/dynamin-dependent but caveolus-independent endocytic pathway. Using inhibitors/small interfering RNA (siRNA) against dynamin and clathrin, we show for the first time that endocytosis of Lewisx-containing glycans is required to drive alternative maturation of antigen-presenting cells and Th2 immune responses. We identified mouse SIGNR-1 as a cell surface receptor for LNFPIII conjugates. Elimination of SIGNR-1 showed no effect on uptake of LNFPIII conjugates, suggesting that other receptors bind to and facilitate uptake of LNFPIII conjugates. We demonstrate that disruption of actin filaments partially prevented the entry of LNFPIII conjugates into APCs and that LNFPIII colocalizes with both early and late endosomal markers and follows the classical endosomal pathway leading to lysosome maturation. The results of this study show that the ability of LNFPIII to induce alternative activation utilizes a receptor-mediated process that requires a dynamin-dependent endocytosis. Thus, key steps have been defined in the previously unknown mechanism of alternative activation that ultimately leads to induction of anti-inflammatory responses. PMID:24566617

  6. Anticancer principles from medicinal piper ( hú jiāo) plants.

    PubMed

    Wang, Yue-Hu; Morris-Natschke, Susan L; Yang, Jun; Niu, Hong-Mei; Long, Chun-Lin; Lee, Kuo-Hsiung

    2014-01-01

    The ethnomedical uses of Piper ( Hú Jiāo) plants as anticancer agents, in vitro cytotoxic activity of both extracts and compounds from Piper plants, and in vivo antitumor activity and mechanism of action of selected compounds are reviewed in the present paper. The genus Piper (Piperaceae) contains approximately 2000 species, of which 10 species have been used in traditional medicines to treat cancer or cancer-like symptoms. Studies have shown that 35 extracts from 24 Piper species and 32 compounds from Piper plants possess cytotoxic activity. Amide alkaloids account for 53% of the major active principles. Among them, piplartine (piperlongumine) shows the most promise, being toxic to dozens of cancer cell lines and having excellent in vivo activity. It is worthwhile to conduct further anticancer studies both in vitro and in vivo on Piper plants and their active principles. PMID:24872928

  7. Anticancer Principles from Medicinal Piper (胡椒 Hú Jiāo) Plants

    PubMed Central

    Wang, Yue-Hu; Morris-Natschke, Susan L.; Yang, Jun; Niu, Hong-Mei; Long, Chun-Lin; Lee, Kuo-Hsiung

    2014-01-01

    The ethnomedical uses of Piper (胡椒 Hú Jiāo) plants as anticancer agents, in vitro cytotoxic activity of both extracts and compounds from Piper plants, and in vivo antitumor activity and mechanism of action of selected compounds are reviewed in the present paper. The genus Piper (Piperaceae) contains approximately 2000 species, of which 10 species have been used in traditional medicines to treat cancer or cancer-like symptoms. Studies have shown that 35 extracts from 24 Piper species and 32 compounds from Piper plants possess cytotoxic activity. Amide alkaloids account for 53% of the major active principles. Among them, piplartine (piperlongumine) shows the most promise, being toxic to dozens of cancer cell lines and having excellent in vivo activity. It is worthwhile to conduct further anticancer studies both in vitro and in vivo on Piper plants and their active principles. PMID:24872928

  8. The inhibition of antigen-presenting activity of dendritic cells resulting from UV irradiation of murine skin is restored by in vitro photorepair of cyclobutane pyrimidine dimers.

    PubMed

    Vink, A A; Moodycliffe, A M; Shreedhar, V; Ullrich, S E; Roza, L; Yarosh, D B; Kripke, M L

    1997-05-13

    Exposing skin to UVB (280-320 nm) radiation suppresses contact hypersensitivity by a mechanism that involves an alteration in the activity of cutaneous antigen-presenting cells (APC). UV-induced DNA damage appears to be an important molecular trigger for this effect. The specific target cells in the skin that sustain DNA damage relevant to the immunosuppressive effect have yet to be identified. We tested the hypothesis that UV-induced DNA damage in the cutaneous APC was responsible for their impaired ability to present antigen after in vivo UV irradiation. Cutaneous APC were collected from the draining lymph nodes of UVB-irradiated, hapten-sensitized mice and incubated in vitro with liposomes containing a photolyase (Photosomes; Applied Genetics, Freeport, NY), which, upon absorption of photoreactivating light, splits UV-induced cyclobutane pyrimidine dimers. Photosome treatment followed by photoreactivating light reduced the number of dimer-containing APC, restored the in vivo antigen-presenting activity of the draining lymph node cells, and blocked the induction of suppressor T cells. Neither Photosomes nor photoreactivating light alone, nor photoreactivating light given before Photosomes, restored APC activity, and Photosome treatment did not reverse the impairment of APC function when isopsoralen plus UVA (320-400 nm) radiation was used instead of UVB. These controls indicate that the restoration of APC function matched the requirements of Photosome-mediated DNA repair for dimers and post-treatment photoreactivating light. These results provide compelling evidence that it is UV-induced DNA damage in cutaneous APC that leads to reduced immune function. PMID:9144224

  9. Skeletal muscle: a paradigm for testing principles of bioenergetics.

    PubMed

    Kushmerick, M J

    1995-12-01

    Muscular activity converts chemical energy into useful work and metabolism restores muscle to its original state. This essay explores the organization and interactions of the regulatory system(s) which allow this energy balance to occur. The term "energy balance" is used in a biochemical rather than a thermodynamic sense--concerned not with deductions from the physical principles of thermodynamics, but rather with those enzymatic processes which nature evolved and which operate at remarkably fixed stoichiometry. Energy balance is a statement of conservation of energy put into biochemical observables. 31P NMR spectroscopy is one of the most useful techniques for investigating these questions quantitatively under physiological conditions in vivo. The author (1) describes the rules or principles of biochemical energy balance; (2) discusses sample results from human muscle to demonstrate its use in studying this class of questions; (3) presents a simple model of integrated cellular respiration to demonstrate its sufficiency to account for the main observations. PMID:8746843

  10. A correspondence principle

    NASA Astrophysics Data System (ADS)

    Hughes, Barry D.; Ninham, Barry W.

    2016-02-01

    A single mathematical theme underpins disparate physical phenomena in classical, quantum and statistical mechanical contexts. This mathematical "correspondence principle", a kind of wave-particle duality with glorious realizations in classical and modern mathematical analysis, embodies fundamental geometrical and physical order, and yet in some sense sits on the edge of chaos. Illustrative cases discussed are drawn from classical and anomalous diffusion, quantum mechanics of single particles and ideal gases, quasicrystals and Casimir forces.

  11. Pauli Exclusion Principle

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    A principle of quantum theory, devised in 1925 by Wolfgang Pauli (1900-58), which states that no two fermions may exist in the same quantum state. The quantum state of a particle is defined by a set of numbers that describe quantities such as energy, angular momentum and spin. Fermions are particles such as quarks, protons, neutrons and electrons, that have spin = ½ (in units of h/2π, where h is ...

  12. Computational principles of memory.

    PubMed

    Chaudhuri, Rishidev; Fiete, Ila

    2016-03-01

    The ability to store and later use information is essential for a variety of adaptive behaviors, including integration, learning, generalization, prediction and inference. In this Review, we survey theoretical principles that can allow the brain to construct persistent states for memory. We identify requirements that a memory system must satisfy and analyze existing models and hypothesized biological substrates in light of these requirements. We also highlight open questions, theoretical puzzles and problems shared with computer science and information theory. PMID:26906506

  13. Principles of nuclear geology

    SciTech Connect

    Aswathanarayana, U.

    1985-01-01

    This book treats the basic principles of nuclear physics and the mineralogy, geochemistry, distribution and ore deposits of uranium and thorium. The application of nuclear methodology in radiogenic heat and thermal regime of the earth, radiometric prospecting, isotopic age dating, stable isotopes and cosmic-ray produced isotopes is covered. Geological processes, such as metamorphic chronology, petrogenesis, groundwater movement, and sedimentation rate are focussed on.

  14. Solving the confusion of gnaphaliin structure: gnaphaliin A and gnaphaliin B identified as active principles of Gnaphalium liebmannii with tracheal smooth muscle relaxant properties.

    PubMed

    Rodríguez-Ramos, Fernando; Navarrete, Andrés

    2009-06-01

    Inflorescences of Gnaphalium liebmannii, commonly known as "Gordolobo", is the most important remedy in Mexican traditional medicine to treat respiratory diseases, including asthma. By a bioguided fractionation of the n-hexane extract of this plant, following the relaxant effect on guinea pig tracheal smooth muscle, the flavones 5,7-dihydroxy-3,8-dimethoxyflavone (1) and 3,5-dihydroxy-7,8-dimethoxyflavone (2) were identified as the active relaxant compounds. Compounds 1 and 2 showed more potent relaxant properties than aminophylline in this model. Both 1 and 2 have been described as gnaphaliin in the past; here EIMS data, NMR experiments for both compounds, and X-ray diffraction analysis for 1 provided structural information to suggest that 1 and 2 should be named gnaphaliins A and B, respectively. PMID:19505084

  15. Fundamental base closure environmental principles

    SciTech Connect

    Yim, R.A.

    1994-12-31

    Military base closures present a paradox. The rate, scale and timing of military base closures is historically unique. However, each base itself typically does not present unique problems. Thus, the challenge is to design innovative solutions to base redevelopment and remediation issues, while simultaneously adopting common, streamlined or pre-approved strategies to shared problems. The author presents six environmental principles that are fundamental to base closure. They are: remediation not clean up; remediation will impact reuse; reuse will impact remediation; remediation and reuse must be coordinated; environmental contamination must be evaluated as any other initial physical constraint on development, not as an overlay after plans are created; and remediation will impact development, financing and marketability.

  16. Heisenberg's observability principle

    NASA Astrophysics Data System (ADS)

    Wolff, Johanna

    2014-02-01

    Werner Heisenberg's 1925 paper 'Quantum-theoretical re-interpretation of kinematic and mechanical relations' marks the beginning of quantum mechanics. Heisenberg famously claims that the paper is based on the idea that the new quantum mechanics should be 'founded exclusively upon relationships between quantities which in principle are observable'. My paper is an attempt to understand this observability principle, and to see whether its employment is philosophically defensible. Against interpretations of 'observability' along empiricist or positivist lines I argue that such readings are philosophically unsatisfying. Moreover, a careful comparison of Heisenberg's reinterpretation of classical kinematics with Einstein's argument against absolute simultaneity reveals that the positivist reading does not fit with Heisenberg's strategy in the paper. Instead the appeal to observability should be understood as a specific criticism of the causal inefficacy of orbital electron motion in Bohr's atomic model. I conclude that the tacit philosophical principle behind Heisenberg's argument is not a positivistic connection between observability and meaning, but the idea that a theory should not contain causally idle wheels.

  17. Testing the Pauli Exclusion Principle for Electrons

    NASA Astrophysics Data System (ADS)

    Marton, J.; Bartalucci, S.; Bertolucci, S.; Berucci, C.; Bragadireanu, M.; Cargnelli, M.; Curceanu (Petrascu, C.; Di Matteo, S.; Egger, J.-P.; Guaraldo, C.; Iliescu, M.; Ishiwatari, T.; Laubenstein, M.; Milotti, E.; Pietreanu, D.; Piscicchia, K.; Ponta, T.; Romero Vidal, A.; Scordo, A.; Sirghi, D. L.; Sirghi, F.; Sperandio, L.; Vazquez Doce, O.; Widmann, E.; Zmeskal, J.

    2013-07-01

    One of the fundamental rules of nature and a pillar in the foundation of quantum theory and thus of modern physics is represented by the Pauli Exclusion Principle. We know that this principle is extremely well fulfilled due to many observations. Numerous experiments were performed to search for tiny violation of this rule in various systems. The experiment VIP at the Gran Sasso underground laboratory is searching for possible small violations of the Pauli Exclusion Principle for electrons leading to forbidden X-ray transitions in copper atoms. VIP is aiming at a test of the Pauli Exclusion Principle for electrons with high accuracy, down to the level of 10-29 - 10-30, thus improving the previous limit by 3-4 orders of magnitude. The experimental method, results obtained so far and new developments within VIP2 (follow-up experiment at Gran Sasso, in preparation) to further increase the precision by 2 orders of magnitude will be presented.

  18. Ethical Principles: Guiding the Use of Animals in Research.

    ERIC Educational Resources Information Center

    Morrison, Adrian R.

    2003-01-01

    Presents arguments on the use of animals in biological and medical research. Discusses ethical considerations, principles, and animal rights in scientific research. (Contains 21 references.) (Author/YDS)

  19. Defending the beauty of the Invariance Principle

    NASA Astrophysics Data System (ADS)

    Barkana, Itzhak

    2014-01-01

    Customary stability analysis methods for nonlinear nonautonomous systems seem to require a strict condition of uniform continuity. Although extensions of LaSalle's Invariance Principle to nonautonomous systems that mitigate this condition have been available for a long time, they have remained surprisingly unknown or open to misinterpretations. The large scope of the Principle might have misled the prospective users and its application to Control problems has been received with amazing yet clear uneasiness. Counterexamples have been used in order to claim that the Invariance Principle cannot be applied to nonlinear nonautonomous systems. Because the original formulation of the Invariance Principle still imposes conditions that are not necessarily needed, this paper presents a new Invariance Principle that further mitigates previous conditions and thus further expands the scope of stability analysis. A brief comparative review of various alternatives to stability analysis of nonautonomous nonlinear systems and their implications is also presented in order to illustrate that thorough analysis of same examples may actually confirm the efficiency of the Invariance Principle approach when dealing with stability of nonautonomous nonlinear systems problems that may look difficult or even unsolvable otherwise.

  20. Enhanced In Vivo Tumor Detection by Active Tumor Cell Targeting Using Multiple Tumor Receptor-Binding Peptides Presented on Genetically Engineered Human Ferritin Nanoparticles.

    PubMed

    Kwon, Koo Chul; Ko, Ho Kyung; Lee, Jiyun; Lee, Eun Jung; Kim, Kwangmeyung; Lee, Jeewon

    2016-08-01

    Human ferritin heavy-chain nanoparticle (hFTH) is genetically engineered to present tumor receptor-binding peptides (affibody and/or RGD-derived cyclic peptides, named 4CRGD here) on its surface. The affibody and 4CRGD specifically and strongly binds to human epidermal growth factor receptor I (EGFR) and human integrin αvβ3, respectively, which are overexpressed on various tumor cells. Through in vitro culture of EGFR-overexpressing adenocarcinoma (MDA-MB-468) and integrin-overexpressing glioblastoma cells (U87MG), it is clarified that specific interactions between receptors on tumor cells and receptor-binding peptides on engineered hFTH is critical in active tumor cell targeting. After labeling with the near-infrared fluorescence dye (Cy5.5) and intravenouse injection into MDA-MB-468 or U87MG tumor-bearing mice, the recombinant hFTHs presenting either peptide or both of affibody and 4CRGD are successfully delivered to and retained in the tumor for a prolonged period of time. In particular, the recombinant hFTH presenting both affibody and 4CRGD notably enhances in vivo detection of U87MG tumors that express heterogeneous receptors, integrin and EGFR, compared to the other recombinant hFTHs presenting either affibody or 4CRGD only. Like affibody and 4CRGD used in this study, other multiple tumor receptor-binding peptides can be also genetically introduced to the hFTH surface for actively targeting of in vivo tumors with heterogenous receptors. PMID:27356892

  1. Two- vs. three-dimensional presentation of mental rotation tasks: Sex differences and effects of training on performance and brain activation

    PubMed Central

    Neubauer, Aljoscha C.; Bergner, Sabine; Schatz, Martina

    2010-01-01

    The well-documented sex difference in mental rotation favoring males has been shown to emerge only for 2-dimensional presentations of 3-dimensional objects, but not with actual 3-dimensional objects or with virtual reality presentations of 3-dimensional objects. Training studies using computer games with mental rotation-related content have demonstrated training effects on mental rotation performance. Here, we studied the combined effect of a two-week mental rotation (MR) training on 2-dimensional vs. 3-dimensional presentations of a classic Shepard–Metzler task (presented in a pretest–training–posttest design) and their accompanying cortical activation patterns assessed via EEG in a sample of 38 male and 39 female adolescents of about 15 years of age. Analysis of one performance parameter (reaction times) displayed only main effects of dimensionality (with shorter RTs on the 3D vs. 2D version of the MR task) and of training (significant shortening of RTs), but no significant sex difference. Analysis of the other performance parameter (scores) in the MR task revealed a sex difference favoring males that first, appeared only in the 2D version, but not in the 3D version of the MR task and, secondly, diminished after training. Neurophysiologically we observed a complex sex × dimensionality × training × hemisphere interaction showing that the hypothesized decrease of brain activation (increase in neural efficiency) with training emerged for males in both 2D and 3D conditions, whereas for females this decrease was found only in the 3D but not with the 2D version of the MR task. PMID:20953415

  2. Eu(2+)-Activated Phase-Pure Oxonitridosilicate Phosphor in a Ba-Si-O-N System via Facile Silicate-Assisted Routes Designed by First-Principles Thermodynamic Simulation.

    PubMed

    Yun, Young Jun; Kim, Jin Kyu; Ju, Ji Young; Choi, Seul Ki; Park, Woon Ik; Jung, Ha-Kyun; Kim, Yongseon; Choi, Sungho

    2016-09-01

    Eu(2+)-activated single phase Ba(2+)-oxonitridosilicate phosphors were prepared under a mild synthetic condition via silicate precursors, and their luminescent properties were investigated. Both the preferred oxonitridosilicate formation as for the available host compounds and thermodynamic stability within the Ba-Si-O-N system were elucidated in detail by the theoretical simulation based on the first-principles density functional theory. Those results can visualize the optimum synthetic conditions for Eu(2+)-activated highly luminescent Ba(2+)-oxonitridosilicates, especially Ba3Si6O12N2, as promising conversion phosphors for white LEDs, including Ba3Si6O9N4 and BaSi2O2N2 phases. To prove the simulated design rule, we synthesized the Ba3Si6O12N2:Eu(2+) phosphor using various silicate precursors, Ba2Si4O10, Ba2Si3O8, and BaSiO3, in a carbothermal reduction ambient and finally succeeded in obtaining a phase of pure highly luminescent oxonitridosilicate phosphor without using any solid-state nitride addition and/or high pressure synthetic procedures. Our study provides useful guidelines for robust synthetic procedures for developing thermally stable rare-earth-ion activated oxonitridosilicate phosphors and an established simulation method that can be effectively applied to other multigas systems. PMID:27518370

  3. Comparative analysis of radical scavenging and antioxidant activity of phenolic compounds present in everyday use spice plants by means of spectrophotometric and chromatographic methods.

    PubMed

    Stankevičius, Mantas; Akuņeca, Ieva; Jãkobsone, Ida; Maruška, Audrius

    2011-06-01

    Comparative analysis of radical scavenging and antioxidant activities of phenolic compounds present in everyday use spice plants was carried out by means of spectrophotometric and chromatographic methods. Six spice plant samples, namely onion (Allium cepa), parsley (Petroselinum crispum) roots and leaves, celery (Apium graveolens) roots and leaves and leaves of dill (Anethum graveolens) were analyzed. Total amount of phenolic compounds and radical scavenging activity (RSA) was the highest in celery leaves and dill extracts and was the lowest in celery roots. Comparing commonly used spectrophotometric analysis of 2,2-diphenyl-1-picrylhydrazyl (DPPH) RSA of extracts with the results obtained using reversed-phase chromatographic separation with on-line post-column radical scavenging reaction detection, good correlation was obtained (R(2)=0.848). Studies using HPLC system with electrochemical detector showed that bioactive phytochemicals can be separated and antioxidant activities of individual compounds evaluated without the need of a complex HPLC system with reaction detector. The results obtained using electrochemical detection correlate with the RSA assayed using spectrophotometric method (R(2)=0.893). PMID:21504067

  4. Early Signaling in Primary T Cells Activated by Antigen Presenting Cells Is Associated with a Deep and Transient Lamellal Actin Network

    PubMed Central

    Roybal, Kole T.; Mace, Emily M.; Mantell, Judith M.; Verkade, Paul; Orange, Jordan S.; Wülfing, Christoph

    2015-01-01

    Cellular signaling transduction critically depends on molecular interactions that are in turn governed by dynamic subcellular distributions of the signaling system components. Comprehensive insight into signal transduction requires an understanding of such distributions and cellular structures driving them. To investigate the activation of primary murine T cells by antigen presenting cells (APC) we have imaged more than 60 signaling intermediates during T cell stimulation with microscopy across resolution limits. A substantial number of signaling intermediates associated with a transient, wide, and actin-associated lamellum extending from an interdigitated T cell:APC interface several micrometers into the T cell, as characterized in detail here. By mapping the more than 60 signaling intermediates onto the spatiotemporal features of cell biological structures, the lamellum and other ones previously described, we also define distinct spatial and temporal characteristics of T cell signal initiation, amplification, and core signaling in the activation of primary T cells by APCs. These characteristics differ substantially from ones seen when T cells are activated using common reductionist approaches. PMID:26237050

  5. Biological activities of Schottenol and Spinasterol, two natural phytosterols present in argan oil and in cactus pear seed oil, on murine miroglial BV2 cells

    SciTech Connect

    El Kharrassi, Youssef; Samadi, Mohammad; Lopez, Tatiana; Nury, Thomas; El Kebbaj, Riad; Andreoletti, Pierre; El Hajj, Hammam I.; Vamecq, Joseph; Moustaid, Khadija; Latruffe, Norbert; El Kebbaj, M’Hammed Saïd; Masson, David; and others

    2014-04-11

    Highlights: • Sterol composition in argan oil and in cactus seed oil. • Chemical synthesis of two sterols: Schottenol and Spinasterol. • Sterols from argan oil or from cactus seed oil show no toxicity on BV2 cells. • Schottenol and Spinasterol modulate the activation and the expression of two nuclear receptors, LXRα and LXRβ. - Abstract: The objective of this study was to evaluate the biological activities of the major phytosterols present in argan oil (AO) and in cactus seed oil (CSO) in BV2 microglial cells. Accordingly, we first determined the sterol composition of AO and CSO, showing the presence of Schottenol and Spinasterol as major sterols in AO. While in CSO, in addition to these two sterols, we found mainly another sterol, the Sitosterol. The chemical synthesis of Schottenol and Spinasterol was performed. Our results showed that these two phytosterols, as well as sterol extracts from AO or CSO, are not toxic to microglial BV2 cells. However, treatments by these phytosterols impact the mitochondrial membrane potential. Furthermore, both Schottenol and Spinasterol can modulate the gene expression of two nuclear receptors, liver X receptor (LXR)-α and LXRβ, their target genes ABCA1 and ABCG1. Nonetheless, only Schottenol exhibited a differential activation vis-à-vis the nuclear receptor LXRβ. Thus Schottenol and Spinasterol can be considered as new LXR agonists, which may play protective roles by the modulation of cholesterol metabolism.

  6. Insight into the active phase of CO oxidation on Ni/Pt and NiO1 - x/Pt model catalysts from a first principles investigation

    NASA Astrophysics Data System (ADS)

    Wang, Chen; Lv, Yong-kang; Wang, Gui-Chang

    2013-08-01

    CO oxidation on bimetallic and metal oxide has drawn much attention in the past years due to its importance both technologically and theoretically, but the active phase as well as the detailed reaction mechanism on the bimetallic surface oxide (i.e., a sandwich-like surface structure) are still unclear. In this work, the CO oxidation on the various Pt-Ni model catalysts [including Pt(111), Pt/Ni/Pt(111), Ni/Pt(111), NiO1 - x/Pt(111) and NiO1 - x/Pt/Ni/Pt(111)] was studied by performing the density functional theory calculations. It was found that the CO oxidation reaction would process with a higher reaction barrier on metals at lower oxygen coverage via the Langmuir-Hinshelwood (L-H) mechanism, whereas CO oxidation reaction would take place with a lower barrier at higher oxygen coverage on metals or in the presence of molecular oxygen/CO (on NiO1 - x-like systems) via the Eley-Rideal mechanism. The calculation results show that the activation energy of CO oxidation follows the order: Pt(111) (0.75 eV) > Pt/Ni/Pt(111) (0.69 eV) > Ni/Pt(111) (0.47 eV at 1 ML oxygen), which is in general agreement with the experimental observations. On the surface oxide NiO1 - x/Pt(111) and NiO1 - x/Pt/Ni/Pt(111) systems, it was found that the molecular CO can subtract the surface lattice oxygen to form CO2 spontaneously through the Eley-Rideal mechanism on NiO1 - x/Pt/Ni/Pt(111), whereas such kinetic behavior cannot occur on the NiO1 - x/Pt(111) system, suggesting the high reactivity of CO oxidation on NiO1 - x/Pt/Ni/Pt(111). The possible reason was analyzed by the magnitude of surface oxygen vacancy formation energy, namely NiO1 - x/Pt/M/Pt(111) with relatively low vacancy formation energy as compared to that of NiO1 - x/Pt(111) (3.46 vs 4.51 eV). Moreover, we extend the above study to a more general case in which the subsurface metals in NiO1 - x/Pt/M/Pt(111) system including VIII group metals like Fe/Co/Ni and the IB group metals like Cu, and it was found that the molecular CO

  7. The Physical Principles of Magnetism

    NASA Astrophysics Data System (ADS)

    Morrish, Allan H.

    2001-01-01

    " The Physical Principles of Magnetism . . . is such a classic a comprehensive introduction to all aspects of magnetism . . . The corrected reissue is a welcome addition to this much-needed archival series. Dr. Morrish presents an excellent introduction to the physics and mathematics of magnetism without oversimplification . . . This respected and timeless book clearly elucidates these principles."" Edward Della Torre, The George Washington University, President of the IEEE Magnetics Society The IEEE Press is pleased to reissue this essential book for understanding the basis of modern magnetic materials. Diamagnetism, paramagnetism, ferromagnetism, ferrimagnetism, and antiferromagnetism are covered in an integrated manner unifying subject matter from physics, chemistry, metallurgy, and engineering. Magnetic phenomena are discussed both from an experimental and theoretical point of view. The underlying physical principles are presented first, followed by macroscopic or microscopic theories. Although quantum mechanical theories are given, a phenomenological approach is emphasized. More than half the book is devoted to a discussion of strongly coupled dipole systems, where the molecular field theory is emphasized. THE PHYSICAL PRINCIPLES OF MAGNETISM is a classic must read for anyone working in the magnetics, electromagnetics, computing, and communications fields. About the Author Allan Henry Morrish is a distinguished professor of physics at the University of Manitoba, Canada. He received a B.Sc. degree from the University of Manitoba in 1943, an M.A. from the University of Toronto in 1946, and a Ph.D. from the University of Chicago in 1949, specializing in nuclear physics. From 1953 to 1964, Dr. Morrish was with the Department of Electrical Engineering at the University of Minnesota at Minneapolis, where he held the rank of professor from 1959. During 1974-1975, Dr. Morrish was president of the Canadian Association of Physicists and in 1977 he was awarded their gold

  8. A Classroom Presents the Constitution of the United States: A Story for Elementary School Children, and Materials for a Classroom Presentation of the Constitution of the United States: Script, Props, and Activities for Elementary School Children.

    ERIC Educational Resources Information Center

    Howes, Janice

    The first of these two booklets illustrates the presenting of an elementary class play about the U.S. Constitution. It can be used to give young children some basic information about the U.S. Constitution or as a guideline for presenting a program about the U.S. Constitution. The story provides important information about the Constitutional…

  9. Upregulation of Immunoproteasome Subunits in Myositis Indicates Active Inflammation with Involvement of Antigen Presenting Cells, CD8 T-Cells and IFNγ

    PubMed Central

    Ghannam, Khetam; Martinez-Gamboa, Lorena; Spengler, Lydia; Krause, Sabine; Smiljanovic, Biljana; Bonin, Marc; Bhattarai, Salyan; Grützkau, Andreas; Burmester, Gerd-R.

    2014-01-01

    Objective In idiopathic inflammatory myopathies (IIM) infiltration of immune cells into muscle and upregulation of MHC-I expression implies increased antigen presentation and involvement of the proteasome system. To decipher the role of immunoproteasomes in myositis, we investigated individual cell types and muscle tissues and focused on possible immune triggers. Methods Expression of constitutive (PSMB5, -6, -7) and corresponding immunoproteasomal subunits (PSMB8, -9, -10) was analyzed by real-time RT-PCR in muscle biopsies and sorted peripheral blood cells of patients with IIM, non-inflammatory myopathies (NIM) and healthy donors (HD). Protein analysis in muscle biopsies was performed by western blot. Affymetrix HG-U133 platform derived transcriptome data from biopsies of different muscle diseases and from immune cell types as well as monocyte stimulation experiments were used for validation, coregulation and coexpression analyses. Results Real-time RT-PCR revealed significantly increased expression of immunoproteasomal subunits (PSMB8/-9/-10) in DC, monocytes and CD8+ T-cells in IIM. In muscle biopsies, the immunosubunits were elevated in IIM compared to NIM and exceeded levels of matched blood samples. Proteins of PSMB8 and -9 were found only in IIM but not NIM muscle biopsies. Reanalysis of 78 myositis and 20 healthy muscle transcriptomes confirmed these results and revealed involvement of the antigen processing and presentation pathway. Comparison with reference profiles of sorted immune cells and healthy muscle confirmed upregulation of PSMB8 and -9 in myositis biopsies beyond infiltration related changes. This upregulation correlated highest with STAT1, IRF1 and IFNγ expression. Elevation of T-cell specific transcripts in active IIM muscles was accompanied by increased expression of DC and monocyte marker genes and thus reflects the cell type specific involvement observed in peripheral blood. Conclusions Immunoproteasomes seem to indicate IIM activity and

  10. The principle of conformational signaling.

    PubMed

    Tompa, Peter

    2016-07-25

    Signal transduction is the primary process by which cells respond to changes in their physical and chemical environments. Cellular response is initiated through a signaling protein (a receptor), which interacts with the "signal", most often a novel molecule outside or inside the cell. The mechanism of activation of the receptor is a conformational change and/or covalent modification, which then sets in motion a signaling pathway, i.e. a cascade of modification and binding events that relay and amplify the message to eventually alter the state of the cell. In reflection of this general perception, concepts such as the "second messenger" and the "phosphorylation cascade" dominate our views of signal transduction. The idea I advocate here is that the non-covalent change in protein conformation itself might serve as the initial or intermittent "signal" in the cascade, and it is often the primary event being recognized and interpreted by downstream receptor(s). This signaling principle is intertwined with many other cellular regulatory concepts, such as (pathway) allostery, conformational spread, induced folding/unfolding, conformational memory, the hierarchical assembly of complexes, and the action of regulatory chaperones and prions. By elaborating on many examples and also recent advances in experimental methodology, I show that conformational signaling, although thus far underappreciated, is a general and robust signaling principle that most of the time operates in close interplay with covalent signals in the cell. PMID:27242242

  11. Structure of RavA MoxR AAA+ protein reveals the design principles of a molecular cage modulating the inducible lysine decarboxylase activity

    PubMed Central

    El Bakkouri, Majida; Gutsche, Irina; Kanjee, Usheer; Zhao, Boyu; Yu, Miao; Goret, Gael; Schoehn, Guy; Burmeister, Wim P.; Houry, Walid A.

    2010-01-01

    The MoxR family of AAA+ ATPases is widespread throughout bacteria and archaea but remains poorly characterized. We recently found that the Escherichia coli MoxR protein, RavA (Regulatory ATPase variant A), tightly interacts with the inducible lysine decarboxylase, LdcI/CadA, to form a unique cage-like structure. Here, we present the X-ray structure of RavA and show that the αβα and all-α subdomains in the RavA AAA+ module are arranged as in magnesium chelatases rather than as in classical AAA+ proteins. RavA structure also contains a discontinuous triple-helical domain as well as a β-barrel-like domain forming a unique fold, which we termed the LARA domain. The LARA domain was found to mediate the interaction between RavA and LdcI. The RavA structure provides insights into how five RavA hexamers interact with two LdcI decamers to form the RavA-LdcI cage-like structure. PMID:21148420

  12. Fine-grained clay fraction (,0.2 {mu}m): An interesting tool to approach the present thermal and permeability state in active geothermal systems

    SciTech Connect

    Patrier, P.; Papapanagiotou, P.; Beaufort, D.; Traineau, H.; Bril, H.

    1992-01-01

    We have investigated by X-ray diffraction the very fine grained secondary minerals (< 0.2 {micro}m) developed in geothermal systems, in relation with their present thermal and permeability state. Because the smallest particles are the most reactive part of a rock, they are the youngest mineral phases of the geothermal fields. This study has been performed on two active geothermal fields: Milos field, Greece (130 < T < 320 C) and Chipilapa field, Salvador (90 < T < 215 C). In the Milos field, the mineralogical composition of the < 0.2 {micro}m clay fraction observed in the reservoir strongly differs from the overlying altered metamorphic schists in the presence of abundant quantities of saponite and talc/saponite interstratified minerals at unusually high temperature. These phases are considered to be kinetically control-led ''metastable'' minerals which rapidly evolve towards actinolite and talc for present temperatures higher than 300 C. Their occurrence is a good indicator of discharge in highly permeable zones. In the geothermal field of Chipilapa, the mineralogical composition of the < 0.2 {micro}m clay fractions fairly agrees with the temperatures presently measured in the wells, whereas several discrepancies may be pointed out from the compositions of coarser clay fractions (< 5 {micro}m) which contain minerals inherited from higher temperature stages. Permeable zones may be evidenced from an increase of expandable components in the interstratified minerals and a decrease of the coherent domain of the unexpandable clay particles (chlorite).

  13. Principles of tendon transfers.

    PubMed

    Coulet, B

    2016-04-01

    Tendon transfers are carried out to restore functional deficits by rerouting the remaining intact muscles. Transfers are highly attractive in the context of hand surgery because of the possibility of restoring the patient's ability to grip. In palsy cases, tendon transfers are only used when a neurological procedure is contraindicated or has failed. The strategy used to restore function follows a common set of principles, no matter the nature of the deficit. The first step is to clearly distinguish between deficient muscles and muscles that could be transferred. Next, the type of palsy will dictate the scope of the program and the complexity of the gripping movements that can be restored. Based on this reasoning, a surgical strategy that matches the means (transferable muscles) with the objectives (functions to restore) will be established and clearly explained to the patient. Every paralyzed hand can be described using three parameters. 1) Deficient segments: wrist, thumb and long fingers; 2) mechanical performance of muscles groups being revived: high energy-wrist extension and finger flexion that require strong transfers with long excursion; low energy-wrist flexion and finger extension movements that are less demanding mechanically, because they can be accomplished through gravity alone in some cases; 3) condition of the two primary motors in the hand: extrinsics (flexors and extensors) and intrinsics (facilitator). No matter the type of palsy, the transfer surgery follows the same technical principles: exposure, release, fixation, tensioning and rehabilitation. By performing an in-depth analysis of each case and by following strict technical principles, tendon transfer surgery leads to reproducible results; this allows the surgeon to establish clear objectives for the patient preoperatively. PMID:27117119

  14. Principles of thermoacoustic energy harvesting

    NASA Astrophysics Data System (ADS)

    Avent, A. W.; Bowen, C. R.

    2015-11-01

    Thermoacoustics exploit a temperature gradient to produce powerful acoustic pressure waves. The technology has a key role to play in energy harvesting systems. A time-line in the development of thermoacoustics is presented from its earliest recorded example in glass blowing through to the development of the Sondhauss and Rijke tubes to Stirling engines and pulse-tube cryo-cooling. The review sets the current literature in context, identifies key publications and promising areas of research. The fundamental principles of thermoacoustic phenomena are explained; design challenges and factors influencing efficiency are explored. Thermoacoustic processes involve complex multi-physical coupling and transient, highly non-linear relationships which are computationally expensive to model; appropriate numerical modelling techniques and options for analyses are presented. Potential methods of harvesting the energy in the acoustic waves are also examined.

  15. Benthic foraminifera from the deep-water Niger delta (Gulf of Guinea): Assessing present-day and past activity of hydrate pockmarks

    NASA Astrophysics Data System (ADS)

    Fontanier, C.; Koho, K. A.; Goñi-Urriza, M. S.; Deflandre, B.; Galaup, S.; Ivanovsky, A.; Gayet, N.; Dennielou, B.; Grémare, A.; Bichon, S.; Gassie, C.; Anschutz, P.; Duran, R.; Reichart, G. J.

    2014-12-01

    We present ecological and isotopic (δ18O and δ13C) data on benthic foraminifera sampled from 4 deep-sea stations in a pockmark field from the deep-water Niger delta (Gulf of Guinea, Equatorial Atlantic Ocean). In addition, a series of sedimentological and (bio)geochemical data are shown to back up foraminiferal observations. All stations are located within 1.2 km of each other, so prevailing oceanographic conditions can be assumed to be similar at each site. Two of the sites (GMMC-01 and GMMC-02) are located in a pockmark (named "pockmark A") where current methane seepages were recorded by ROV observations. A third station (GMMC-03) is located in the topographic depression interpreted as a collapsed pockmark (named "pockmark B"). The fourth site (GMMC-04) is a reference station, without evidence of past or present seepages. Our observations show that degraded organic matter with low bio-availability is present at all stations with a preferential burial of organic compounds in topographic depressions (GMMC-03 station). Authigenic aragonite is abundant in surface sediments at stations GMMC-01 and -02. Its precipitation is likely related to high rates of methane oxidation during past seep events in episodically active pockmark A. In contrast, the absence of anaerobic methanotrophic Archaea (ANME) during the sampling period (November 2011) suggests that only moderate sulphide and methane oxidation take place close to the sediment-water interface. Compared to the reference site GMMC-04, living foraminifera at the collapsed and episodically active pockmarks show minor changes in terms of diversity, standing stocks and faunal composition. However, the δ13C signal of living and dead (but well-preserved) foraminiferal species (Ceratobulimina contraria, Melonis barleeanus, Uvigerina peregrina) is depleted in the episodically active pockmark A compared to the other stations. Overgrowth of authigenic carbonate on altered foraminifera generates an important shift to lower

  16. Protection - Principles and practice.

    NASA Technical Reports Server (NTRS)

    Graham, G. S.; Denning, P. J.

    1972-01-01

    The protection mechanisms of computer systems control the access to objects, especially information objects. The principles of protection system design are formalized as a model (theory) of protection. Each process has a unique identification number which is attached by the system to each access attempted by the process. Details of system implementation are discussed, taking into account the storing of the access matrix, aspects of efficiency, and the selection of subjects and objects. Two systems which have protection features incorporating all the elements of the model are described.

  17. The principle of reciprocity.

    PubMed

    Hoult, D I

    2011-12-01

    The circumstances surrounding the realisation that NMR signal reception could be quantified in a simple fundamental manner using Lorentz's Principle of Reciprocity are described. The poor signal-to-noise ratio of the first European superconducting magnet is identified as a major motivating factor, together with the author's need to understand phenomena at a basic level. A summary is then given of the thought processes leading to the very simple pseudo-static formula that has been the basis of signal-to-noise calculations for over a generation. PMID:21889377

  18. Talus fractures: surgical principles.

    PubMed

    Rush, Shannon M; Jennings, Meagan; Hamilton, Graham A

    2009-01-01

    Surgical treatment of talus fractures can challenge even the most skilled foot and ankle surgeon. Complicated fracture patterns combined with joint dislocation of variable degrees require accurate assessment, sound understanding of principles of fracture care, and broad command of internal fixation techniques needed for successful surgical care. Elimination of unnecessary soft tissue dissection, a low threshold for surgical reduction, liberal use of malleolar osteotomy to expose body fracture, and detailed attention to fracture reduction and joint alignment are critical to the success of treatment. Even with the best surgical care complications are common and seem to correlate with injury severity and open injuries. PMID:19121756

  19. Nonequilibrium quantum Landauer principle.

    PubMed

    Goold, John; Paternostro, Mauro; Modi, Kavan

    2015-02-13

    Using the operational framework of completely positive, trace preserving operations and thermodynamic fluctuation relations, we derive a lower bound for the heat exchange in a Landauer erasure process on a quantum system. Our bound comes from a nonphenomenological derivation of the Landauer principle which holds for generic nonequilibrium dynamics. Furthermore, the bound depends on the nonunitality of dynamics, giving it a physical significance that differs from other derivations. We apply our framework to the model of a spin-1/2 system coupled to an interacting spin chain at finite temperature. PMID:25723198

  20. Principles of smile design

    PubMed Central

    Bhuvaneswaran, Mohan

    2010-01-01

    An organized and systematic approach is required to evaluate, diagnose and resolve esthetic problems predictably. It is of prime importance that the final result is not dependent only on the looks alone. Our ultimate goal as clinicians is to achieve pleasing composition in the smile by creating an arrangement of various esthetic elements. This article reviews the various principles that govern the art of smile designing. The literature search was done using PubMed search and Medline. This article will provide a basic knowledge to the reader to bring out a functional stable smile. PMID:21217950

  1. Teaching Elements and Principles of Bridge Design

    ERIC Educational Resources Information Center

    Beck, Charles

    2005-01-01

    Bridge construction is a popular classroom activity. However, the basic principles of tension, compression, and counterbalance are not always clearly represented and defined. The common materials used to construct model bridges, such as straws, toothpicks, Legos[TM], and building blocks, are often too flexible or stationary to demonstrate the…

  2. Qualitative biomechanical principles for application in coaching.

    PubMed

    Knudson, Duane

    2007-01-01

    Many aspects of human movements in sport can be readily understood by Newtonian rigid-body mechanics. Many of these laws and biomechanical principles, however, are counterintuitive to a lot of people. There are also several problems in the application of biomechanics to sports, so the application of biomechanics in the qualitative analysis of sport skills by many coaches has been limited. Biomechanics scholars have long been interested in developing principles that facilitate the qualitative application of biomechanics to improve movement performance and reduce the risk of injury. This paper summarizes the major North American efforts to establish a set of general biomechanical principles of movement, and illustrates how principles can be used to improve the application of biomechanics in the qualitative analysis of sport technique. A coach helping a player with a tennis serve is presented as an example. The standardization of terminology for biomechanical principles is proposed as an important first step in improving the application ofbiomechanics in sport. There is also a need for international cooperation and research on the effectiveness of applying biomechanical principles in the coaching of sport techniques. PMID:17542182

  3. Science Activities in Energy: Chemical Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 15 activities relating to chemical energy. Activities are simple, concrete experiments for fourth, fifth and sixth grades which illustrate principles and problems relating to energy. Each activity is outlined on a single card which is introduced by a question. A teacher's…

  4. Science Activities in Energy: Electrical Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 16 activities relating to electrical energy. Activities are simple, concrete experiments for fourth, fifth and sixth grades which illustrate principles and problems relating to energy. Each activity is outlined in a single card which is introduced by a question. A teacher's…

  5. Science Activities in Energy: Solar Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 12 activities relating to solar energy. Activities are simple, concrete experiments for fourth, fifth, and sixth grades, which illustrate principles and problems relating to energy. Each activity is outlined on a single card which is introduced by a question. A teacher's supplement…

  6. Academic Principles: A Brief Introduction

    ERIC Educational Resources Information Center

    Association of American Universities, 2013

    2013-01-01

    For many decades certain core principles have guided the conduct of teaching, research, and scholarship at American universities, as well as the ways in which these institutions are governed. There is ample evidence that these principles have strongly contributed to the quality of American universities. The principles have also made these…

  7. Archimedes' Principle in General Coordinates

    ERIC Educational Resources Information Center

    Ridgely, Charles T.

    2010-01-01

    Archimedes' principle is well known to state that a body submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the body. Herein, Archimedes' principle is derived from first principles by using conservation of the stress-energy-momentum tensor in general coordinates. The resulting expression for the force is…

  8. Principles of climate service development

    NASA Astrophysics Data System (ADS)

    Buontempo, Carlo; Liggins, Felicity; Newton, Paula

    2015-04-01

    In November 2014, a group of 30 international experts in climate service development gathered in Honiton, UK, to discuss and identify the key principles that should be considered when developing new climate services by all the actors involved. Through an interactive and dynamic workshop the attendees identified seven principles. This contribution summarises these principles.

  9. Translation of the mRNA of the maize transcriptional activator Opaque-2 is inhibited by upstream open reading frames present in the leader sequence.

    PubMed Central

    Lohmer, S; Maddaloni, M; Motto, M; Salamini, F; Thompson, R D

    1993-01-01

    The protein encoded by the Opaque-2 (O2) gene is a transcription factor, translated from an mRNA that possesses an unusually long 5' leader sequence containing three upstream open reading frames (uORFs). The efficiency of translation of O2 mRNA has been tested in vivo by a transient assay in which the level of activation of the b32 promoter, a natural target of O2 protein, is measured. We show that uORF-less O2 alleles possess a higher transactivation value than the wild-type allele and that the reduction in transactivation due to the uORFs is a cis-dominant effect. The data presented indicate that both uORF1 and uORF2 are involved in the reducing effect and suggest that both are likely to be translated. PMID:8439744

  10. Acidic deposition and its effects on forest productivity: a review of the present state of knowledge, research activities, and information needs

    SciTech Connect

    Pinkerton, J.E.

    1981-01-01

    The present state of knowledge with regard to acid deposition is reviewed. Sources include the literature and direct contact with persons responsible for carrying out all completed, ongoing, and planned research activities, national and international, related to acidic deposition and its effects, with emphasis on forest productivity. In addition, a list of information needs in seven areas was developed, these include: a characterization of forest soils to define their sensitivity to acidic deposition; effects on forest soil chemical and biological processes; development of improved dry deposition measurement methods; changes in precipitation composition due to forest canopies; more extensive monitoring of acidic deposition in industry owned forest lands; expansion of long-term greenhouse and controlled field experiments; and the relationship of acidic deposition and intensive forestry management practices. 85 references. (MDF)

  11. General principles of antimicrobial therapy.

    PubMed

    Leekha, Surbhi; Terrell, Christine L; Edson, Randall S

    2011-02-01

    Antimicrobial agents are some of the most widely, and often injudiciously, used therapeutic drugs worldwide. Important considerations when prescribing antimicrobial therapy include obtaining an accurate diagnosis of infection; understanding the difference between empiric and definitive therapy; identifying opportunities to switch to narrow-spectrum, cost-effective oral agents for the shortest duration necessary; understanding drug characteristics that are peculiar to antimicrobial agents (such as pharmacodynamics and efficacy at the site of infection); accounting for host characteristics that influence antimicrobial activity; and in turn, recognizing the adverse effects of antimicrobial agents on the host. It is also important to understand the importance of antimicrobial stewardship, to know when to consult infectious disease specialists for guidance, and to be able to identify situations when antimicrobial therapy is not needed. By following these general principles, all practicing physicians should be able to use antimicrobial agents in a responsible manner that benefits both the individual patient and the community. PMID:21282489

  12. Nutrition, diet, physical activity, smoking, and longevity: from primitive hunter-gatherer to present passive consumer--how far can we go?

    PubMed

    Walker, Alexander R P; Walker, Betty F; Adam, Fatima

    2003-02-01

    In millennia past, and until recently, among hunter-gatherers and like populations, in all populations, in measure, down through the ages, the securing of sufficient food was life's primary purpose. Virtually all people were physically very active during early life and later in their everyday occupations. In contrast, nowadays, in Western populations, with relative abundance of food, the way of life is mainly one of enjoyment of meals, of work, and of leisure time, in a context of as few as one child per family, and with long survival times of about 75 to 80 y, due in large part to much reduced child mortality and the effective treatments of disorders and diseases. As to changes in food consumption, compared with the erratic and often monotonous fares of the past, both far and not so distant, everyday diets have changed tremendously in variety, nutritional value, and palatability such that, inter alia, overeating is almost inevitable. Compounding the latter, sedentariness is the rule, in contrast to the previously very high level of everyday physical activity in the masses of populations. In consequence, one speculation is that, by 2230, "all Americans will be obese." Although the living of much longer lives is highly gratifying, understandably, all wish to have longer "healthy life expectancy," i.e. to suffer as little as possible before death. However, with regard to the present-day "passive consumer," although the practical recommendations for leading still healthier lives, dietarily and non-dietarily, are well known, very few are interested, and still fewer practice them. Nevertheless, for the few who, with determination, are eager to improve their lifestyles, there could be highly profitable lengthening of years of "healthy life expectancy" by eating less, eating more plant foods, being much more physically active, and restricting non-dietary risk factors (smoking, alcohol consumption). PMID:12591555

  13. Biological activities of Schottenol and Spinasterol, two natural phytosterols present in argan oil and in cactus pear seed oil, on murine miroglial BV2 cells.

    PubMed

    El Kharrassi, Youssef; Samadi, Mohammad; Lopez, Tatiana; Nury, Thomas; El Kebbaj, Riad; Andreoletti, Pierre; El Hajj, Hammam I; Vamecq, Joseph; Moustaid, Khadija; Latruffe, Norbert; El Kebbaj, M'Hammed Saïd; Masson, David; Lizard, Gérard; Nasser, Boubker; Cherkaoui-Malki, Mustapha

    2014-04-11

    The objective of this study was to evaluate the biological activities of the major phytosterols present in argan oil (AO) and in cactus seed oil (CSO) in BV2 microglial cells. Accordingly, we first determined the sterol composition of AO and CSO, showing the presence of Schottenol and Spinasterol as major sterols in AO. While in CSO, in addition to these two sterols, we found mainly another sterol, the Sitosterol. The chemical synthesis of Schottenol and Spinasterol was performed. Our results showed that these two phytosterols, as well as sterol extracts from AO or CSO, are not toxic to microglial BV2 cells. However, treatments by these phytosterols impact the mitochondrial membrane potential. Furthermore, both Schottenol and Spinasterol can modulate the gene expression of two nuclear receptors, liver X receptor (LXR)-α and LXRβ, their target genes ABCA1 and ABCG1. Nonetheless, only Schottenol exhibited a differential activation vis-à-vis the nuclear receptor LXRβ. Thus Schottenol and Spinasterol can be considered as new LXR agonists, which may play protective roles by the modulation of cholesterol metabolism. PMID:24582563

  14. Principles of immunology.

    PubMed

    Lentz, Ashley K; Feezor, Robert J

    2003-12-01

    The immune system, composed of innate and acquired immunity, allows an organism to fight off foreign pathogens. Healthy immunity accomplishes four essential principles: (1) ability to detect and fight off infection; (2) ability to recognize a host's own cells as "self," thereby protecting them from attack; (3) a memory from previous foreign infections; and (4) ability to limit the response after the pathogen has been removed. In an unaltered state, the intricate network of immunologic organs and cells creates an environment for proper host defense. Without adequate execution of immunologic mechanisms, a host is rendered defenseless against pathogens. Conversely, an unchecked immune response can be self-destructive. As a result of either of these untoward sequelae, immune dysfunction can elicit disease states in the host. The goal of this review is to elucidate the characteristics of a healthy immune system, focusing on the principles of immunity and the cells that participate in host protection. We also briefly discuss the clinical ramifications of immune dysfunction. PMID:16215081

  15. DOE Collegiate Wind Competition (Presentation)

    SciTech Connect

    Jones, J.

    2014-02-01

    This presentation for the January Stakeholder Engagement and Outreach webinar outlines the expanded need for workers in the wind industry and provides an overview of the DOE Wind Competition (to be held in May 2014) and the guiding principles of the competition.

  16. Aposematism and the handicap principle.

    PubMed

    Holen, Øistein Haugsten; Svennungsen, Thomas Owens

    2012-11-01

    Aposematic prey use conspicuous warning signals to advertise their defenses to predators. It has long been recognized that the efficiency of a warning signal may be reduced if poorly defended prey (automimics) are present in the population. The handicap principle suggests that the use of warning signals by poorly defended prey may be kept in check if signaling is costly. Three mechanisms that involve signal costs have been proposed to facilitate honest warning signals in prey: go-slow behavior in predators, resource allocation trade-offs, and costs of detection alone. We study all three in a unified game-theoretical framework. We find that the go-slow mechanism and the resource allocation mechanism can introduce differential benefits and differential costs of signaling, respectively, and can support honest signaling in accordance with the handicap principle. When honest signaling is maintained by the go-slow mechanism, conspicuous prey will necessarily suffer more attacks on average than cryptic prey. In contrast, when honest signaling is maintained by the resource allocation mechanism, cryptic prey will suffer more attacks. The detection cost mechanism lacks differential costs and benefits, and its potential for maintaining honest signaling equilibria is limited. We relate our results to intra- and interspecific correlations between conspicuousness and defense. PMID:23070323

  17. Principles of rehabilitation and reactivation.

    PubMed

    Osadnik, Christian R; Rodrigues, Fernanda M M; Camillo, Carlos A; Loeckx, Matthias; Janssens, Wim; Dooms, Christophe; Troosters, Thierry

    2015-01-01

    Skeletal muscle dysfunction and physical inactivity are two clinically important features of a wide range of acute and chronic respiratory conditions. Optimisation of both of these features is important in order to improve physical function, prevent clinical deterioration and maximise community participation. One of the most potent and evidence-based interventions to address these physical deficits is pulmonary rehabilitation (PR). Whilst the majority of PR research has been conducted in patients with chronic obstructive pulmonary disease, there is widespread recognition that PR can benefit many other respiratory patient groups. These include patients with interstitial lung diseases, asthma, pulmonary hypertension, pre-/post-lung surgery (e.g. lung cancer, transplantation) and cystic fibrosis to name a few. Exercise training must be appropriately prescribed by a skilled healthcare professional with comprehensive knowledge of the pathology and physiology of these conditions, as well as a sound understanding of the exercise physiology and core principles of exercise prescription, monitoring and progression. It has also become increasingly recognised that people with respiratory conditions, particularly those with chronic disease, are considerably less active than those of good health. PR should therefore aim to induce behavioural change to facilitate the adoption and maintenance of an active lifestyle. In addition, PR should pay attention to the psychological well-being of patients and self-management of their lung disease in all its aspects. To that end, multidisciplinary individualised programs should be offered. This review sets the scene of PR principles for a series of papers that will focus on specific diseases other than chronic obstructive pulmonary disease where rehabilitation may offer a clinically important aspect of care over and above conventional pharmacological treatment. PMID:25591614

  18. Principles of Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Landé, Alfred

    2013-10-01

    Preface; Introduction: 1. Observation and interpretation; 2. Difficulties of the classical theories; 3. The purpose of quantum theory; Part I. Elementary Theory of Observation (Principle of Complementarity): 4. Refraction in inhomogeneous media (force fields); 5. Scattering of charged rays; 6. Refraction and reflection at a plane; 7. Absolute values of momentum and wave length; 8. Double ray of matter diffracting light waves; 9. Double ray of matter diffracting photons; 10. Microscopic observation of ρ (x) and σ (p); 11. Complementarity; 12. Mathematical relation between ρ (x) and σ (p) for free particles; 13. General relation between ρ (q) and σ (p); 14. Crystals; 15. Transition density and transition probability; 16. Resultant values of physical functions; matrix elements; 17. Pulsating density; 18. General relation between ρ (t) and σ (є); 19. Transition density; matrix elements; Part II. The Principle of Uncertainty: 20. Optical observation of density in matter packets; 21. Distribution of momenta in matter packets; 22. Mathematical relation between ρ and σ; 23. Causality; 24. Uncertainty; 25. Uncertainty due to optical observation; 26. Dissipation of matter packets; rays in Wilson Chamber; 27. Density maximum in time; 28. Uncertainty of energy and time; 29. Compton effect; 30. Bothe-Geiger and Compton-Simon experiments; 31. Doppler effect; Raman effect; 32. Elementary bundles of rays; 33. Jeans' number of degrees of freedom; 34. Uncertainty of electromagnetic field components; Part III. The Principle of Interference and Schrödinger's equation: 35. Physical functions; 36. Interference of probabilities for p and q; 37. General interference of probabilities; 38. Differential equations for Ψp (q) and Xq (p); 39. Differential equation for фβ (q); 40. The general probability amplitude Φβ' (Q); 41. Point transformations; 42. General theorem of interference; 43. Conjugate variables; 44. Schrödinger's equation for conservative systems; 45. Schr

  19. Iron diffusion from first principles calculations

    NASA Astrophysics Data System (ADS)

    Wann, E.; Ammann, M. W.; Vocadlo, L.; Wood, I. G.; Lord, O. T.; Brodholt, J. P.; Dobson, D. P.

    2013-12-01

    The cores of Earth and other terrestrial planets are made up largely of iron1 and it is therefore very important to understand iron's physical properties. Chemical diffusion is one such property and is central to many processes, such as crystal growth, and viscosity. Debate still surrounds the explanation for the seismologically observed anisotropy of the inner core2, and hypotheses include convection3, anisotropic growth4 and dendritic growth5, all of which depend on diffusion. In addition to this, the main deformation mechanism at the inner-outer core boundary is believed to be diffusion creep6. It is clear, therefore, that to gain a comprehensive understanding of the core, a thorough understanding of diffusion is necessary. The extremely high pressures and temperatures of the Earth's core make experiments at these conditions a challenge. Low-temperature and low-pressure experimental data must be extrapolated across a very wide gap to reach the relevant conditions, resulting in very poorly constrained values for diffusivity and viscosity. In addition to these dangers of extrapolation, preliminary results show that magnetisation plays a major role in the activation energies for diffusion at low pressures therefore creating a break down in homologous scaling to high pressures. First principles calculations provide a means of investigating diffusivity at core conditions, have already been shown to be in very good agreement with experiments7, and will certainly provide a better estimate for diffusivity than extrapolation. Here, we present first principles simulations of self-diffusion in solid iron for the FCC, BCC and HCP structures at core conditions in addition to low-temperature and low-pressure calculations relevant to experimental data. 1. Birch, F. Density and composition of mantle and core. Journal of Geophysical Research 69, 4377-4388 (1964). 2. Irving, J. C. E. & Deuss, A. Hemispherical structure in inner core velocity anisotropy. Journal of Geophysical

  20. Activities.

    ERIC Educational Resources Information Center

    Moody, Mally

    1992-01-01

    A series of four activities are presented to enhance students' abilities to appreciate and use trigonometry as a tool in problem solving. Activities cover problems applying the law of sines, the law of cosines, and matching equivalent trigonometric expressions. A teacher's guide, worksheets, and answers are provided. (MDH)

  1. Are fish and standardized FETAX assays protective enough for amphibians? A case study on Xenopus laevis larvae assay with biologically active substances present in livestock wastes.

    PubMed

    Martini, Federica; Tarazona, José V; Pablos, M Victoria

    2012-01-01

    Biologically active substances could reach the aquatic compartment when livestock wastes are considered for recycling. Recently, the standardized FETAX assay has been questioned, and some researchers have considered that the risk assessment performed on fish could not be protective enough to cover amphibians. In the present study a Xenopus laevis acute assay was developed in order to compare the sensitivity of larvae relative to fish or FETAX assays; veterinary medicines (ivermectin, oxytetracycline, tetracycline, sulfamethoxazole, and trimethoprim) and essential metals (zinc, copper, manganese, and selenium) that may be found in livestock wastes were used for the larvae exposure. Lethal (LC(50)) and sublethal effects were estimated. Available data in both, fish and FETAX studies, were in general more protective than values found out in the current study, but not in all cases. Moreover, the presence of nonlethal effects, caused by ivermectin, zinc, and copper, suggested that several physiological mechanisms could be affected. Thus, this kind of effects should be deeply investigated. The results obtained in the present study could expand the information about micropollutants from livestock wastes on amphibians. PMID:22629159

  2. Are Fish and Standardized FETAX Assays Protective Enough for Amphibians? A Case Study on Xenopus laevis Larvae Assay with Biologically Active Substances Present in Livestock Wastes

    PubMed Central

    Martini, Federica; Tarazona, José V.; Pablos, M. Victoria

    2012-01-01

    Biologically active substances could reach the aquatic compartment when livestock wastes are considered for recycling. Recently, the standardized FETAX assay has been questioned, and some researchers have considered that the risk assessment performed on fish could not be protective enough to cover amphibians. In the present study a Xenopus laevis acute assay was developed in order to compare the sensitivity of larvae relative to fish or FETAX assays; veterinary medicines (ivermectin, oxytetracycline, tetracycline, sulfamethoxazole, and trimethoprim) and essential metals (zinc, copper, manganese, and selenium) that may be found in livestock wastes were used for the larvae exposure. Lethal (LC50) and sublethal effects were estimated. Available data in both, fish and FETAX studies, were in general more protective than values found out in the current study, but not in all cases. Moreover, the presence of nonlethal effects, caused by ivermectin, zinc, and copper, suggested that several physiological mechanisms could be affected. Thus, this kind of effects should be deeply investigated. The results obtained in the present study could expand the information about micropollutants from livestock wastes on amphibians. PMID:22629159

  3. Supramolecular Chemistry And Self-assembly Special Feature: Selective immobilization of proteins to self-assembled monolayers presenting active site-directed capture ligands

    NASA Astrophysics Data System (ADS)

    Hodneland, Christian D.; Lee, Young-Sam; Min, Dal-Hee; Mrksich, Milan

    2002-04-01

    This paper describes a method for the selective and covalent immobilization of proteins to surfaces with control over the density and orientation of the protein. The strategy is based on binding of the serine esterase cutinase to a self-assembled monolayer presenting a phosphonate ligand and the subsequent displacement reaction that covalently binds the ligand to the enzyme active site. Surface plasmon resonance (SPR) spectroscopy showed that cutinase binds irreversibly to a monolayer presenting the capture ligand at a density of 1% mixed among tri(ethylene glycol) groups. The covalent immobilization is specific for cutinase, and the glycol-terminated monolayer effectively prevents unwanted nonspecific adsorption of proteins. To demonstrate that the method could be used to immobilize proteins of interest, a cutinase-calmodulin fusion protein was constructed and immobilized to the monolayer. SPR showed that calcineurin selectively associated with the immobilized calmodulin. This capture ligand immobilization method combines the advantages that the immobilization reaction is highly selective for the intended protein, the tether is covalent and, hence, stable, and the method avoids the need for synthetic modification and rigorous purification of proteins before immobilization. These characteristics make the method well suited to a range of applications and, in particular, for constructing protein microarrays.

  4. Liquid Water on the Surface of Mars Today: Present Gully Activity Observed by the Mars Reconnaissance Orbiter (MRO) and Mars Global Surveyor (MGS) and Direction for Future Missions

    NASA Astrophysics Data System (ADS)

    Harrison, T. N.; Malin, M. C.; Edgett, K. S.

    2009-12-01

    Eight new flows in martian mid-latitude gullies have been found using the MRO Context Camera and MGS Mars Orbiter Camera. Each formed during 1999-2009. Using MRO HiRISE images, we find that the morphology and inferred emplacement behavior of these features is consistent with those of debris flows fluidized by a liquid medium and not by dry, granular flows. Evidence comes from the patterns of flow around obstacles, ponding in and subsequent overtopping of topographic depressions, and super-elevation of deposits on channel banks where the channels change direction, attributes consistent with a liquid but not with fluid-like granular flow. Additional evidence includes anastomoses in distal reaches and lobate terminations. Of the 8 flows, 3 have formation dates constrained to within a single Mars year (although not the same year); these 3 formed during autumn to early spring, demonstrating that summer warming is not participating in creating the liquid (i.e., that would melt snow or ice). The new gully deposits indicate that some gullies are currently active, suggesting that Mars has liquid water today and it occasionally appears on the planet’s surface. NASA’s Mars Exploration Program has focused on the “follow the water” theme and is now shifting toward “habitability” and life detection. Places where liquid water comes to the Martian surface today warrant detailed investigation. Martian astrobiology involves the search for evidence of extinct and extant life. Discovery of ancient sedimentary rocks shifted emphasis from the Viking-era pursuit of present-day microbial life to MSL’s focus on habitable environments. Recent descriptions of contemporary methane production have renewed interest in searching for extant life. Missions to locations of potential present day life, whether indicated by methane or liquid water, must deal with the associated planetary protection issues (they are “special regions”). More information about such locations is critical

  5. Role of the mononuclear phagocyte as an antigen-presenting cell for human gamma delta T cells activated by live Mycobacterium tuberculosis.

    PubMed Central

    Boom, W H; Chervenak, K A; Mincek, M A; Ellner, J J

    1992-01-01

    gamma delta T cells, both human and murine, have been found to be highly responsive to mycobacterial antigens. However, the role and function of gamma delta T cells in the immune response to Mycobacterium tuberculosis remain largely unknown. In earlier studies, we demonstrated that monocytes infected with live M. tuberculosis were particularly effective inducers of human peripheral blood gamma delta T cells. The present studies were performed to further characterize the interaction between human mononuclear phagocytes, gamma delta T cells, and live M. tuberculosis, in comparison with CD4+ T cells. First, we found that resting gamma delta T cells expanded in vitro by live M. tuberculosis were specific for M. tuberculosis, and that heat killing and washing the mycobacteria removed the antigen(s) for gamma delta T cells. In contrast, the heat-killed mycobacteria retained significant antigenicity for CD4+ T cells. Second, live M. tuberculosis-expanded gamma delta T cells from healthy tuberculin-positive donors did not respond significantly to the antigens in M. tuberculosis culture filtrate, including the 65- and 71-kDa mycobacterial heat shock proteins. Third, the activation of gamma delta T cells by live mycobacteria was dependent on antigen-presenting cells, and mononuclear phagocytes were found to be very efficient antigen-presenting cells both for resting peripheral blood gamma delta T cells and for activated expanded gamma delta T cells. The mononuclear phagocyte carried the necessary costimulatory factors necessary for gamma delta T-cell proliferation. Fourth, the antigen repertoire and HLA requirements for CD4+ memory T cells and those for gamma delta T cells appear to be quite distinct from each other. CD4+ T cells recognized both soluble protein antigens and whole organisms in a class II major histocompatibility complex-restricted manner, whereas gamma delta T cells appeared to recognize only constituents associated with the whole organism and were not

  6. Does the Relative Strength of Grouping Principles Modulate the Interactions between them?

    PubMed

    Montoro, Pedro R; Luna, Dolores

    2015-01-01

    This study examines the influence of the relative strength of grouping principles on interactions between the intrinsic principle of proximity and the extrinsic principle of common region in the process of perceptual organization. Cooperation and competition between intrinsic and extrinsic principles were examined by presenting the principle either alone or conjoined with another principle. The relative grouping strength of the principles operating alone was varied in two different groups of participants so that it was similar for one group and very different for the other group. Results showed that, when principles acting alone had different strengths, the grouping effect of the strongest principle was similar to that of the cooperation condition, and the effect of the weakest principle was similar to that of competing conjoined principles. In contrast, when the strength of principles acting alone was similar, the effect of conjoined cooperating principles was greater than that of either principle acting alone. Moreover, the effect of conjoined competing principles was smaller than that of either principle operating alone. Results show that cooperation and competition between intrinsic and extrinsic principles are modulated by the relative grouping strength of principles acting alone. Furthermore, performance in these conditions could be predicted on the basis of performance in single-principle conditions. PMID:26046305

  7. Biomass Program Overview Presentation

    SciTech Connect

    2011-12-01

    This presentation is an interactive walk through of the Program's vision of advancing the biofuels and bioproducts industry and highlights the research and development activities that will help achieve it.

  8. Physical Principle for Generation of Randomness

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2009-01-01

    A physical principle (more precisely, a principle that incorporates mathematical models used in physics) has been conceived as the basis of a method of generating randomness in Monte Carlo simulations. The principle eliminates the need for conventional random-number generators. The Monte Carlo simulation method is among the most powerful computational methods for solving high-dimensional problems in physics, chemistry, economics, and information processing. The Monte Carlo simulation method is especially effective for solving problems in which computational complexity increases exponentially with dimensionality. The main advantage of the Monte Carlo simulation method over other methods is that the demand on computational resources becomes independent of dimensionality. As augmented by the present principle, the Monte Carlo simulation method becomes an even more powerful computational method that is especially useful for solving problems associated with dynamics of fluids, planning, scheduling, and combinatorial optimization. The present principle is based on coupling of dynamical equations with the corresponding Liouville equation. The randomness is generated by non-Lipschitz instability of dynamics triggered and controlled by feedback from the Liouville equation. (In non-Lipschitz dynamics, the derivatives of solutions of the dynamical equations are not required to be bounded.)

  9. Principles for Community College Finance. Commission Report 83-14.

    ERIC Educational Resources Information Center

    California State Postsecondary Education Commission, Sacramento.

    Prompted by the expiration of existing funding mechanisms for California's community colleges in June 1983, this report presents the results of the California Postsecondary Education Commission's (CPEC's) review and revision of its principles for community college funding. First, background material is presented on the financial principles adopted…

  10. ABCDEFG IS - the principle of constructive feedback.

    PubMed

    Bhattarai, M

    2007-01-01

    Feedback is an integral part of any learning experience. Constructive feedback is a powerful instrument and facilitates the learner's professional and personal development. "ABCDEFG IS", a mnemonic for the principles of constructive feedback, stands for Amount of the information, Benefit of the trainees, Change behaviour, Descriptive language, Environment, Focused, Group check, Interpretation check, and Sharing information. The eight important steps of feedback are: Ensure prior information, Collect data, Make appropriate meeting arrangement, Begin by encouraging self assessment by the trainee, Highlight areas where the trainee is doing well, Give feedback, Handle reaction maintaining the dignity and Plan actions. Communication and reflection also share many of the principles and steps of constructive feedback and giving regular feedback, thus, helps to improve communication and reflection. The feedback provider would be able to provide genuine feedback by following the appropriate steps and principles of constructive feedback and realize how important and rewarding its role is in teaching learning activities. PMID:18274573

  11. Basic Principles in Oncology

    NASA Astrophysics Data System (ADS)

    Vogl, Thomas J.

    The evolving field of interventional oncology can only be considered as a small integrative part in the complex area of oncology. The new field of interventional oncology needs a standardization of the procedures, the terminology, and criteria to facilitate the effective communication of ideas and appropriate comparison between treatments and new integrative technology. In principle, ablative therapy is a part of locoregional oncological therapy and is defined either as chemical ablation using ethanol or acetic acid, or thermotherapies such as radiofrequency, laser, microwave, and cryoablation. All these new evolving therapies have to be exactly evaluated and an adequate terminology has to be used to define imaging findings and pathology. All the different technologies and evaluated therapies have to be compared, and the results have to be analyzed in order to improve the patient outcome.

  12. Kepler and Mach's Principle

    NASA Astrophysics Data System (ADS)

    Barbour, Julian

    The definitive ideas that led to the creation of general relativity crystallized in Einstein's thinking during 1912 while he was in Prague. At the centenary meeting held there to mark the breakthrough, I was asked to talk about earlier great work of relevance to dynamics done at Prague, above all by Kepler and Mach. The main topics covered in this chapter are: some little known but basic facts about the planetary motions; the conceptual framework and most important discoveries of Ptolemy and Copernicus; the complete change of concepts that Kepler introduced and their role in his discoveries; the significance of them in Newton's work; Mach's realization that Kepler's conceptual revolution needed further development to free Newton's conceptual world of the last vestiges of the purely geometrical Ptolemaic world view; and the precise formulation of Mach's principle required to place GR correctly in the line of conceptual and technical evolution that began with the ancient Greek astronomers.

  13. Dynamical principles in neuroscience

    SciTech Connect

    Rabinovich, Mikhail I.; Varona, Pablo; Selverston, Allen I.; Abarbanel, Henry D. I.

    2006-10-15

    Dynamical modeling of neural systems and brain functions has a history of success over the last half century. This includes, for example, the explanation and prediction of some features of neural rhythmic behaviors. Many interesting dynamical models of learning and memory based on physiological experiments have been suggested over the last two decades. Dynamical models even of consciousness now exist. Usually these models and results are based on traditional approaches and paradigms of nonlinear dynamics including dynamical chaos. Neural systems are, however, an unusual subject for nonlinear dynamics for several reasons: (i) Even the simplest neural network, with only a few neurons and synaptic connections, has an enormous number of variables and control parameters. These make neural systems adaptive and flexible, and are critical to their biological function. (ii) In contrast to traditional physical systems described by well-known basic principles, first principles governing the dynamics of neural systems are unknown. (iii) Many different neural systems exhibit similar dynamics despite having different architectures and different levels of complexity. (iv) The network architecture and connection strengths are usually not known in detail and therefore the dynamical analysis must, in some sense, be probabilistic. (v) Since nervous systems are able to organize behavior based on sensory inputs, the dynamical modeling of these systems has to explain the transformation of temporal information into combinatorial or combinatorial-temporal codes, and vice versa, for memory and recognition. In this review these problems are discussed in the context of addressing the stimulating questions: What can neuroscience learn from nonlinear dynamics, and what can nonlinear dynamics learn from neuroscience?.

  14. The renewal of aristocratic principles.

    PubMed

    Didić, E

    1999-06-01

    The term of "aristocracy" has always risen various questions, such as its real meaning, its role, its types, its purposes, who composes aristocracy, etc. In this text, I have tried to give my point of view to those questions, not only in a historical and traditional line of development, but also applied to present systems, relations and sets of values. I have differentiated two types of aristocracy, so called "aristocracy of soul" and "aristocracy of property" and decsribed main features. Furthermore, there is a view to traditional role of aristocracy, its principles and laws of existence, together with its dangers. Based on those categories, further direction of development leads to the questions of aristocracy in democratic societies with all the contemporary "specificum". The last part deals with the matter of aristocracy in regard to politics and its wide range of application. PMID:10402730

  15. Present activity and seismogenic potential of a low-angle normal fault system (Città di Castello, Italy): Constraints from surface geology, seismic reflection data and seismicity

    NASA Astrophysics Data System (ADS)

    Brozzetti, Francesco; Boncio, Paolo; Lavecchia, Giusy; Pace, Bruno

    2009-01-01

    We present new constraints on an active low-angle normal fault system in the Città di Castello-Sansepolcro basin (CSB) of the northern Apennines of Italy. New field data from the geological survey of the Carta Geologica d' Italia (CARG project) define the surface geometry of the normal fault system and lead to an interpretation of the CROP 03 deep-crust seismic reflection profile (Castiglion Fiorentino-Urbania segment), with particular attention paid to the geometry of the Plio-Quaternary extensional structures. Surface and sub-surface geological data are integrated with instrumental and historical seismicity in order to define the seismotectonics of the area. Low-angle east-dipping reflectors are the seismic expression of the well-known Altotiberina Fault (AF), a regional extensional detachment on which both east- and west-dipping high-angle faults, bounding the CSB, sole out. The AF breakaway zone is located ˜ 10 km west of the CSB. Within the extensional allochthon, synthetic east-dipping planes prevail. Displacement along the AF is ˜ 4.5 km, which agrees with the cumulative offset due to its synthetic splays. The evolution of the CSB has mainly been controlled by the east-dipping fault system, at least since Early Pleistocene time; this system is still active and responsible for the seismicity of the area. A low level of seismic activity was recorded instrumentally within the CSB, but several damaging earthquakes have occurred in historical times. The instrumental seismicity and the intensity data points of the largest historical earthquakes (5 events with maximum MCS intensity of IX to IX-X) allow us to propose two main seismogenic structures: the Monte Santa Maria Tiberina (Mmax = 5.9) and Città di Castello (Mmax up to 6.5) normal faults. Both are synthetic splays of the AF detachment, dipping to the NE at moderate (45-50°) to low (25-30°) angles and cutting the upper crust up to the surface. This study suggests that low-angle normal faults (at least

  16. Developing Principles for Best Practice in Expanded School Mental Health

    ERIC Educational Resources Information Center

    Weist, Mark D.; Sander, Mark A.; Walrath, Christine; Link, Benjaman; Nabors, Laura; Adelsheim, Steve; Moore, Elizabeth; Jennings, Jenni; Carrillo, Kristine

    2005-01-01

    On the basis of activities of a federally funded national center for school mental health, review of literature on principles for best practice in child and adolescent mental health and school health, and consultation with national experts and family members, a set of 10 principles for best practice in school mental health was developed. A survey…

  17. Basic principles of variable speed drives

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.

    1973-01-01

    An understanding of the principles which govern variable speed drive operation is discussed for successful drive application. The fundamental factors of torque, speed ratio, and power as they relate to drive selection are discussed. The basic types of variable speed drives, their operating characteristics and their applications are also presented.

  18. Least Action Principle on an Air Table

    ERIC Educational Resources Information Center

    Provost, J. P.

    1975-01-01

    Presents a mathematical demonstration that the least action principle enables both the trajectories and the conservation laws (of energy, momentum, and angular momentum) to be obtained without using Lagrange's equations. Discusses an experimental procedure which utilizes air tables to demonstrate the conservation laws and interactions at a…

  19. Basic Principles of Animal Science. Reprinted.

    ERIC Educational Resources Information Center

    Florida State Dept. of Education, Tallahassee.

    The reference book is designed to fulfill the need for organized subject matter dealing with basic principles of animal science to be incorporated into the high school agriculture curriculum. The material presented is scientific knowledge basic to livestock production. Five units contain specific information on the following topics: anatomy and…

  20. A Theoretical Foundation for Tilden's Interpretive Principles.

    ERIC Educational Resources Information Center

    Hammitt, William E.

    1981-01-01

    Draws from perceptual and cognitive psychology to present a theoretical basis for the principles of interpretation developed by Freeman Tilden. Emphasized is cognitive map theory which holds that information units people receive, code and store are structured into cognitive models intended to represent the environment. (Author/WB)