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Sample records for reaction class approach

  1. A combined reaction class approach with integrated molecular orbital+molecular orbital (IMOMO) methodology: A practical tool for kinetic modeling

    International Nuclear Information System (INIS)

    Truong, Thanh N.; Maity, Dilip K.; Truong, Thanh-Thai T.

    2000-01-01

    We present a new practical computational methodology for predicting thermal rate constants of reactions involving large molecules or a large number of elementary reactions in the same class. This methodology combines the integrated molecular orbital+molecular orbital (IMOMO) approach with our recently proposed reaction class models for tunneling. With the new methodology, we show that it is possible to significantly reduce the computational cost by several orders of magnitude while compromising the accuracy in the predicted rate constants by less than 40% over a wide range of temperatures. Another important result is that the computational cost increases only slightly as the system size increases. (c) 2000 American Institute of Physics

  2. Model reduction of detailed-balanced reaction networks by clustering linkage classes

    NARCIS (Netherlands)

    Rao, Shodhan; Jayawardhana, Bayu; van der Schaft, Abraham; Findeisen, Rolf; Bullinger, Eric; Balsa-Canto, Eva; Bernaerts, Kristel

    2016-01-01

    We propose a model reduction method that involves sequential application of clustering of linkage classes and Kron reduction. This approach is specifically useful for chemical reaction networks with each linkage class having less number of reactions. In case of detailed balanced chemical reaction

  3. Giant resonances: reaction theory approach

    International Nuclear Information System (INIS)

    Toledo Piza, A.F.R. de; Foglia, G.A.

    1989-09-01

    The study of giant resonances through the use of reaction theory approach is presented and discussed. Measurements of cross-sections to the many available decay channels following excitation of giant multipole resonances (GMR) led one to view these phenomena as complicated dynamical syndromes so that theoretical requirements for their study must be extended beyond the traditional bounds of nuclear structure models. The spectra of decay products following GMR excitation in heavy nuclei are well described by statistical model (Hauser-Feshback, HF) predictions indicated that spreading of the collective modes plays a major role in shaping exclusive cross-sections. (A.C.A.S.) [pt

  4. Amazing variational approach to chemical reactions

    OpenAIRE

    Fernández, Francisco M.

    2009-01-01

    In this letter we analyse an amazing variational approach to chemical reactions. Our results clearly show that the variational expressions are unsuitable for the analysis of empirical data obtained from chemical reactions.

  5. Subaltern Classes, Class Struggles and Hegemony : a Gramscian Approach

    Directory of Open Access Journals (Sweden)

    Ivete Simionatto

    2009-01-01

    Full Text Available This article sought to revive the concept of subaltern classes and their relation with other categories, particularly the State, civil society and hegemony in the thinking of Antonio Gramsci, as a support for contemporary class struggles. It also analyzes the relations between subaltern classes, common sense and ideology, as well as the forms of “overcoming” conceptualized by Gramsci, through the culture and philosophy of praxis. The paper revives the discussion of the subaltern classes, based on the original Gramscian formulation in the realm of Marxism, through the dialectic interaction between structure and superstructure, economy and politics. In addition to the conceptual revival, it indicates some elements that can support the discussion of the forms of subalternity found in contemporary reality and the possibilities for strengthening the struggles of these class layers, above all in moments of strong demobilization of popular participation.

  6. Graduate and undergraduate students’ reaction to the teaching procedures used in semipresential classes

    Directory of Open Access Journals (Sweden)

    Henry Maia Peixoto

    2013-12-01

    Full Text Available The objective of this study was to investigate the reactions of undergraduate and graduate students to the teaching procedures used in semipresential classes. This exploratory study was performed with a quantitative approach at a public university, with undergraduate and graduate students who had completed semipresential classes on health promotion education. Among the 19 evaluated teaching procedures, 15 (78.9% did not show any statistically significant differences between the two academic levels. The means and medians for most variables, for both undergraduate (78.9% and graduate (89.5% students, were above 7 in a scale ranging between 0 (awful and 10 (excellent. Therefore, it is concluded that both groups showed similar reactions to the teaching procedures and gave satisfactory opinions in this regard. Understanding these aspects can support designing class disciplines that use teaching procedures that are adequate to university students. Descriptors: Education, Distance; Education, Higher; Learning; Educational Measurement.

  7. Mining chemical reactions using neighborhood behavior and condensed graphs of reactions approaches.

    Science.gov (United States)

    de Luca, Aurélie; Horvath, Dragos; Marcou, Gilles; Solov'ev, Vitaly; Varnek, Alexandre

    2012-09-24

    This work addresses the problem of similarity search and classification of chemical reactions using Neighborhood Behavior (NB) and Condensed Graphs of Reaction (CGR) approaches. The CGR formalism represents chemical reactions as a classical molecular graph with dynamic bonds, enabling descriptor calculations on this graph. Different types of the ISIDA fragment descriptors generated for CGRs in combination with two metrics--Tanimoto and Euclidean--were considered as chemical spaces, to serve for reaction dissimilarity scoring. The NB method has been used to select an optimal combination of descriptors which distinguish different types of chemical reactions in a database containing 8544 reactions of 9 classes. Relevance of NB analysis has been validated in generic (multiclass) similarity search and in clustering with Self-Organizing Maps (SOM). NB-compliant sets of descriptors were shown to display enhanced mapping propensities, allowing the construction of better Self-Organizing Maps and similarity searches (NB and classical similarity search criteria--AUC ROC--correlate at a level of 0.7). The analysis of the SOM clusters proved chemically meaningful CGR substructures representing specific reaction signatures.

  8. LLUSTRATION OF AMINO ACIDS REACTIONS AND PROTEINS CHARACTERIZATION FOR EXPERIMENTAL BIOCHEMISTRY CLASSES

    Directory of Open Access Journals (Sweden)

    I. Parreira

    2008-05-01

    Full Text Available New teaching methodologies have been developed to facilitate the learning of biochemistry concepts. A new  approach to Biochemistry  teaching  has become more frequent,  one that does not  require reagents but use photos, videos, softwares etc. Experimental Biochemistry classes, i.e. covering characterization of amino acids and proteins,  might be more productive with the use of complementary didactic material.  Furthermore,  if experiments cannot be implemented, classes may  be well illustrated with complementary didactic material covering from the simplest to the most  complex experiments.  In order to  aid Biochemistry classes without practical experiments, some tests and reactions were documented in our laboratory through digital photos, for  instance: (1 the biuret reaction wherein the blue reagent turns violet in the presence of proteins and changes to pink when combined with short-chain polypeptides; (2 the ninhydrin test used in amino acid analysis of proteins: most of the amino acids are hydrolyzed and react with ninhydrin; when reacting with these free amines, a deep blue or purple color appears; (3 methods for detecting proteins wherein spectrophotometry is used, that deals with the relationship between absorbance, concentration and path length, which constitute the Beer-Lambert Law. A didactic material constituted by texts, schemes and illustrated by photos has been created for each class topic. This material can be used either as a teacher script or in a presentation form to illustrate classes without experimental activities. Financial Support: Pro-Reitoria Graduação-USP, CNPq.

  9. A Latent Class Approach to Estimating Test-Score Reliability

    Science.gov (United States)

    van der Ark, L. Andries; van der Palm, Daniel W.; Sijtsma, Klaas

    2011-01-01

    This study presents a general framework for single-administration reliability methods, such as Cronbach's alpha, Guttman's lambda-2, and method MS. This general framework was used to derive a new approach to estimating test-score reliability by means of the unrestricted latent class model. This new approach is the latent class reliability…

  10. Polymer reaction engineering, an integrated approach

    NARCIS (Netherlands)

    Meyer, T.; Keurentjes, J.T.F.; Meyer, T.; Keurentjes, J.T.F.

    2005-01-01

    Summary This chapter contains sections titled: Polymer Materials A Short History of Polymer Reaction Engineering The Position of Polymer Reaction Engineering Toward Integrated Polymer Reaction Engineering The Disciplines in Polymer Reaction Engineering The Future: Product-inspired Polymer Reaction

  11. Approaching the Speed of Light with Class.

    Science.gov (United States)

    Dance, Rosalie A.; Sandefur, James T.

    1997-01-01

    Describes an experimental approach to determining the speed of light in water using some simple observations and Fermat's principle. Enables students to integrate mathematical techniques and encourages mathematical exploration in which the students have control over what mathematics and technology to use and when to use them. Presents extensions…

  12. A Networks Approach to Modeling Enzymatic Reactions.

    Science.gov (United States)

    Imhof, P

    2016-01-01

    Modeling enzymatic reactions is a demanding task due to the complexity of the system, the many degrees of freedom involved and the complex, chemical, and conformational transitions associated with the reaction. Consequently, enzymatic reactions are not determined by precisely one reaction pathway. Hence, it is beneficial to obtain a comprehensive picture of possible reaction paths and competing mechanisms. By combining individually generated intermediate states and chemical transition steps a network of such pathways can be constructed. Transition networks are a discretized representation of a potential energy landscape consisting of a multitude of reaction pathways connecting the end states of the reaction. The graph structure of the network allows an easy identification of the energetically most favorable pathways as well as a number of alternative routes. © 2016 Elsevier Inc. All rights reserved.

  13. How the Waldorf Approach Changed a Difficult Class.

    Science.gov (United States)

    Mollet, David

    1991-01-01

    Shows how Waldorf methodology, an approach advocating learning as a cooperative venture and nurturing the creative and the artistic, helped a fourth grade teacher inspire a normally uncooperative class to learn fractions. A story involving a young farmer struggling to feed his horses properly was used and accompanied by the children's own…

  14. Serpentinization reaction pathways: implications for modeling approach

    Energy Technology Data Exchange (ETDEWEB)

    Janecky, D.R.

    1986-01-01

    Experimental seawater-peridotite reaction pathways to form serpentinites at 300/sup 0/C, 500 bars, can be accurately modeled using the EQ3/6 codes in conjunction with thermodynamic and kinetic data from the literature and unpublished compilations. These models provide both confirmation of experimental interpretations and more detailed insight into hydrothermal reaction processes within the oceanic crust. The accuracy of these models depends on careful evaluation of the aqueous speciation model, use of mineral compositions that closely reproduce compositions in the experiments, and definition of realistic reactive components in terms of composition, thermodynamic data, and reaction rates.

  15. Computational Approach to Electron Charge Transfer Reactions

    DEFF Research Database (Denmark)

    Jónsson, Elvar Örn

    -molecular mechanics scheme, and tools to analyse statistical data and generate relative free energies and free energy surfaces. The methodology is applied to several charge transfer species and reactions in chemical environments - chemical in the sense that solvent, counter ions and substrate surfaces are taken...... in to account - which directly influence the reactants and resulting reaction through both physical and chemical interactions. All methods are though general and can be applied to different types of chemistry. First, the basis of the various theoretical tools is presented and applied to several test systems...... and asymmetric charge transfer reactions between several first-row transition metals in water. The results are compared to experiments and rationalised with classical analytic expressions. Shortcomings of the methods are accounted for with clear steps towards improved accuracy. Later the analysis is extended...

  16. Class A dioscorins of various yam species suppress ovalbumin-induced allergic reactions.

    Science.gov (United States)

    Yang, Ching-Chi; Lin, Kuo-Chih

    2014-06-01

    Dioscorins, the primary storage proteins in yam tubers, of different species exhibited varying immunomodulatory activities in mice. We inferred that this might be attributed to the various isoforms in the yam tubers. We aimed to investigate the antiallergic potential of the Class A dioscorins of various yam species using the ovalbumin (OVA)-induced murine allergy model. We purified the recombinant Class A dioscorins (rDioscorins) of various yam species from Escherichia coli and evaluated their antiallergic potential by enzyme-linked immunosorbent assay. The Class A rDioscorins of various yam species suppressed allergic reactions by significantly decreasing the serum IgE and histamine levels. The serum IFN-γ and IgG2a levels significantly increased in all rDioscorin-treated mice. The splenocytes of the rDioscorin-treated mice also exhibited upregulated IFN-γ secretion in response to ConA stimulation. By contrast, the serum IL-5 levels decreased to basal levels in mice treated with Class A rDioscorins and the amount of IL-5 produced by splenocytes decreased in response to ConA stimulation. The Class A rDioscorins suppress allergic reactions, possibly through modulating an imbalanced Th1/Th2 immune response to OVA by promoting Th1 cell responses. Furthermore, the Class A rDioscorins of various yam species exhibited similar immunomodulatory activities in OVA-sensitized mice, which were different from the activities demonstrated by native dioscorins, suggesting that distinct immunomodulatory effects of native dioscorins on mice were attributed to the various isoforms in the yam tubers. The Class A dioscorins of various yam species exhibit antiallergic activity and are potential immunotherapeutic agents for treating IgE-mediated hypersensitivity.

  17. News DidacticApproaches in a Health Care Graduation Class

    Directory of Open Access Journals (Sweden)

    S.B. Barreto

    2009-05-01

    Full Text Available Nowadays the educator must focus not only on acquiring cognitive knowledge, but also on other matters and competences (social, political, instrumental ones. This work took placein a private college in Recife and  was had as objectiveto verify the efficiency of the application of ne wsdidactic strategies in graduation classes.This study comprised students subscribed in Medical technology (B andPharmacy   (F/2008. Students were separated in groups regarding their college period and course (B1, B2, F1, F2. The class, divided in two stages, used different didactic strategies to explain its contents: 1st unit: besides the conventionalapproaches (explanatory class, exercises and laboratory classes, new educative activities were included (research practice in the library  and problem solving classes in the laboratory; 2nd unit: conventional approach alone. In the end of each unit, students were evaluated with a theoretical exam (with objective and subjective questions. It was shown that the arithmetic means of the gradesobtained by the 1st unit students  (B1=9,1;  B2=8,8; F1=9,7;  F2=9,5 were greater, in comparison with the 2nd unit ones (B1=7,3;   B2=7,6;  F1=7,6;  F2=8,0. The research and the problem solving classes created multiple interactions opportunities among the group subjects, which may have influenced the results. The total of subjects of each group (B1=60;  B2=34;  F1=50;  F2=35 has also been evaluated, and it was seen that there was no influence of such matter on the obtained results.   Therefore, it may be concluded t hat, the work towards the whole development of the human being demands new didactic approaches and diversification of educationalactivities.

  18. Convergence Analysis of a Class of Computational Intelligence Approaches

    Directory of Open Access Journals (Sweden)

    Junfeng Chen

    2013-01-01

    Full Text Available Computational intelligence approaches is a relatively new interdisciplinary field of research with many promising application areas. Although the computational intelligence approaches have gained huge popularity, it is difficult to analyze the convergence. In this paper, a computational model is built up for a class of computational intelligence approaches represented by the canonical forms of generic algorithms, ant colony optimization, and particle swarm optimization in order to describe the common features of these algorithms. And then, two quantification indices, that is, the variation rate and the progress rate, are defined, respectively, to indicate the variety and the optimality of the solution sets generated in the search process of the model. Moreover, we give four types of probabilistic convergence for the solution set updating sequences, and their relations are discussed. Finally, the sufficient conditions are derived for the almost sure weak convergence and the almost sure strong convergence of the model by introducing the martingale theory into the Markov chain analysis.

  19. "SCAFFOLDING" STUDENTS' WRITING IN EFL CLASS: IMPLEMENTING PROCESS APPROACH

    Directory of Open Access Journals (Sweden)

    Ekaning Dewanti Laksmi

    2006-01-01

    Full Text Available The writing process approach views a writing learner as a creator of text, and hence, he needs to experience what writers actually do as they write, and so do students in EFL writing classes. The approach offers an answer to the need of helping the students develop their writing skill without their having to master the basic fundamental elements of writing, i.e. grammar, prior to attending the writing courses. This article highlights the potential of the process approach-with which students go through a write-rewrite process-in giving students a scaffold to work in a real, live process of how a real writer engages in the process of writing. However, the most important harvest is the fact that students have become more confident in expressing their ideas in writings.

  20. Quantum chemical approach to estimating the thermodynamics of metabolic reactions.

    Science.gov (United States)

    Jinich, Adrian; Rappoport, Dmitrij; Dunn, Ian; Sanchez-Lengeling, Benjamin; Olivares-Amaya, Roberto; Noor, Elad; Even, Arren Bar; Aspuru-Guzik, Alán

    2014-11-12

    Thermodynamics plays an increasingly important role in modeling and engineering metabolism. We present the first nonempirical computational method for estimating standard Gibbs reaction energies of metabolic reactions based on quantum chemistry, which can help fill in the gaps in the existing thermodynamic data. When applied to a test set of reactions from core metabolism, the quantum chemical approach is comparable in accuracy to group contribution methods for isomerization and group transfer reactions and for reactions not including multiply charged anions. The errors in standard Gibbs reaction energy estimates are correlated with the charges of the participating molecules. The quantum chemical approach is amenable to systematic improvements and holds potential for providing thermodynamic data for all of metabolism.

  1. Quantum Chemical Approach to Estimating the Thermodynamics of Metabolic Reactions

    OpenAIRE

    Adrian Jinich; Dmitrij Rappoport; Ian Dunn; Benjamin Sanchez-Lengeling; Roberto Olivares-Amaya; Elad Noor; Arren Bar Even; Alán Aspuru-Guzik

    2014-01-01

    Thermodynamics plays an increasingly important role in modeling and engineering metabolism. We present the first nonempirical computational method for estimating standard Gibbs reaction energies of metabolic reactions based on quantum chemistry, which can help fill in the gaps in the existing thermodynamic data. When applied to a test set of reactions from core metabolism, the quantum chemical approach is comparable in accuracy to group contribution methods for isomerization and group transfe...

  2. Tandem Wittig-ene reaction approach to kainic acid

    Digital Repository Service at National Institute of Oceanography (India)

    Majik, M.S.; Parameswaran, P.S.; Tilve, S.G.

    The first example of a tandem Wittig-intramolecular ene reaction approach and its application toward the synthesis of kainic acid is reported. The synthetic pathway involves conversion of prenyl bromide into phosphorane 3, followed by one-pot Wittig...

  3. Linear decomposition approach for a class of nonconvex programming problems.

    Science.gov (United States)

    Shen, Peiping; Wang, Chunfeng

    2017-01-01

    This paper presents a linear decomposition approach for a class of nonconvex programming problems by dividing the input space into polynomially many grids. It shows that under certain assumptions the original problem can be transformed and decomposed into a polynomial number of equivalent linear programming subproblems. Based on solving a series of liner programming subproblems corresponding to those grid points we can obtain the near-optimal solution of the original problem. Compared to existing results in the literature, the proposed algorithm does not require the assumptions of quasi-concavity and differentiability of the objective function, and it differs significantly giving an interesting approach to solving the problem with a reduced running time.

  4. Sartorial symbols of social class elicit class-consistent behavioral and physiological responses: a dyadic approach.

    Science.gov (United States)

    Kraus, Michael W; Mendes, Wendy Berry

    2014-12-01

    Social rank in human and nonhuman animals is signaled by a variety of behaviors and phenotypes. In this research, we examined whether a sartorial manipulation of social class would engender class-consistent behavior and physiology during dyadic interactions. Male participants donned clothing that signaled either upper-class (business-suit) or lower-class (sweatpants) rank prior to engaging in a modified negotiation task with another participant unaware of the clothing manipulation. Wearing upper-class, compared to lower-class, clothing induced dominance--measured in terms of negotiation profits and concessions, and testosterone levels--in participants. Upper-class clothing also elicited increased vigilance in perceivers of these symbols: Relative to perceiving lower-class symbols, perceiving upper-class symbols increased vagal withdrawal, reduced perceptions of social power, and catalyzed physiological contagion such that perceivers' sympathetic nervous system activation followed that of the upper-class target. Discussion focuses on the dyadic process of social class signaling within social interactions. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  5. Employee Reactions to Merit Pay: Cognitive Approach and Social Approach

    Science.gov (United States)

    Wang, Yingchun

    2010-01-01

    The dissertation aims to tackle one of the most pressing questions facing the merit pay system researchers and practitioners: Why do merit pay raises have such a small effect on employees' satisfaction, commitment and job performance? My approach to the study of this question is to develop explanatory frameworks from two perspectives: cognitive…

  6. A network dynamics approach to chemical reaction networks

    Science.gov (United States)

    van der Schaft, A. J.; Rao, S.; Jayawardhana, B.

    2016-04-01

    A treatment of a chemical reaction network theory is given from the perspective of nonlinear network dynamics, in particular of consensus dynamics. By starting from the complex-balanced assumption, the reaction dynamics governed by mass action kinetics can be rewritten into a form which allows for a very simple derivation of a number of key results in the chemical reaction network theory, and which directly relates to the thermodynamics and port-Hamiltonian formulation of the system. Central in this formulation is the definition of a balanced Laplacian matrix on the graph of chemical complexes together with a resulting fundamental inequality. This immediately leads to the characterisation of the set of equilibria and their stability. Furthermore, the assumption of complex balancedness is revisited from the point of view of Kirchhoff's matrix tree theorem. Both the form of the dynamics and the deduced behaviour are very similar to consensus dynamics, and provide additional perspectives to the latter. Finally, using the classical idea of extending the graph of chemical complexes by a 'zero' complex, a complete steady-state stability analysis of mass action kinetics reaction networks with constant inflows and mass action kinetics outflows is given, and a unified framework is provided for structure-preserving model reduction of this important class of open reaction networks.

  7. Dual unitarisation - a new approach to hadron reactions

    International Nuclear Information System (INIS)

    Chan, H.-M.; Tsou, S.T.

    1976-09-01

    The new approach of dual unitarisation (or topological expansion) to hadron reactions is reviewed with particular emphasis on its aspect as a practical calculational method and the consistent manner in which it has been applied to a wide range of hadronic phenomena. (author)

  8. Identification of a Syndrome Class of Neuropsychiatric Adverse Reactions to Mefloquine from Latent Class Modeling of FDA Adverse Event Reporting System Data.

    Science.gov (United States)

    Nevin, Remington L; Leoutsakos, Jeannie-Marie

    2017-03-01

    Although mefloquine use is known to be associated with a risk of severe neuropsychiatric adverse reactions that are often preceded by prodromal symptoms, specific combinations of neurologic or psychiatric reactions associated with mefloquine use are not well described in the literature. This study sought to identify a distinct neuropsychiatric syndrome class associated with mefloquine use in reports of adverse events. Latent class modeling of US Food and Drug Administration Adverse Event Reporting System (FAERS) data was performed using indicators defined by the Medical Dictionary for Regulatory Activities neurologic and psychiatric high-level group terms, in a study dataset of FAERS reports (n = 5332) of reactions to common antimalarial drugs. A distinct neuropsychiatric syndrome class was identified that was strongly and significantly associated with reports of mefloquine use (odds ratio = 3.92, 95% confidence interval 2.91-5.28), defined by a very high probability of symptoms of deliria (82.7%) including confusion and disorientation, and a moderate probability of other severe psychiatric and neurologic symptoms including dementia and amnesia (18.6%) and seizures (18.1%). The syndrome class was also associated with symptoms that are considered prodromal including anxiety, depression, sleep disturbance, and abnormal dreams, and neurological symptoms such as dizziness, vertigo, and paresthesias. This study confirms in FAERS reports the existence of a severe mefloquine neuropsychiatric syndrome class associated with common symptoms that may be considered prodromal. Clinical identification of the characteristic symptoms of this syndrome class may aid in improving case finding in pharmacovigilance studies of more serious adverse reactions to the drug.

  9. Improved prediction of MHC class I and class II epitopes using a novel Gibbs sampling approach

    DEFF Research Database (Denmark)

    Nielsen, Morten; Lundegaard, Claus; Worning, Peder

    2004-01-01

    Prediction of which peptides will bind a specific major histocompatibility complex (MHC) constitutes an important step in identifying potential T-cell epitopes suitable as vaccine candidates. MHC class II binding peptides have a broad length distribution complicating such predictions. Thus......, identifying the correct alignment is a crucial part of identifying the core of an MHC class II binding motif. In this context, we wish to describe a novel Gibbs motif sampler method ideally suited for recognizing such weak sequence motifs. The method is based on the Gibbs sampling method, and it incorporates...

  10. Two-component multistep direct reactions: A microscopic approach

    International Nuclear Information System (INIS)

    Koning, A.J.; Chadwick, M.B.

    1998-03-01

    The authors present two principal advances in multistep direct theory: (1) A two-component formulation of multistep direct reactions, where neutron and proton excitations are explicitly accounted for in the evolution of the reaction, for all orders of scattering. While this may at first seem to be a formidable task, especially for multistep processes where the many possible reaction pathways becomes large in a two-component formalism, the authors show that this is not so -- a rather simple generalization of the FKK convolution expression 1 automatically generates these pathways. Such considerations are particularly relevant when simultaneously analyzing both neutron and proton emission spectra, which is always important since these processes represent competing decay channels. (2) A new, and fully microscopic, method for calculating MSD cross sections which does not make use of particle-hole state densities but instead directly calculates cross sections for all possible particle-hole excitations (again including an exact book-keeping of the neutron/proton type of the particle and hole at all stages of the reaction) determined from a simple non-interacting shell model. This is in contrast to all previous numerical approaches which sample only a small number of such states to estimate the DWBA strength, and utilize simple analytical formulae for the partial state density, based on the equidistant spacing model. The new approach has been applied, along with theories for multistep compound, compound, and collective reactions, to analyze experimental emission spectra for a range of targets and energies. The authors show that the theory correctly accounts for double-differential nucleon spectra

  11. A hybrid approach for predicting promiscuous MHC class I restricted ...

    Indian Academy of Sciences (India)

    Prakash

    2006-09-15

    Sep 15, 2006 ... with existing MHC binder prediction methods for alleles studied by both ... in locating the promiscuous MHC binding regions from antigen sequence. ... Artificial neural network; MHC class I alleles; promiscuous binders; ... this problem by developing methods for prediction for ... In case equal number of.

  12. A NEW APPROACH TO CLASS SCHEDULING. FINAL REPORT.

    Science.gov (United States)

    CANTER, JOHN; AND OTHERS

    AN INVESTIGATION OF THE USE OF A PROTOTYPE DEVICE FOR CLASS SCHEDULING WAS MADE. THE BEEKLEY INSITE DEVICE THAT WAS STUDIED USES THE "PEEK-A-BOO" PRINCIPLE OF MATCHING COMPUTER TAPES. A TEST GROUP OF 149 GRADUATE STUDENTS WAS USED. THEIR DESIRED SCHEDULES WERE MATCHED AUTOMATICALLY AGAINST A PROPOSED MASTER SCHEDULE TO EVALUATE THE…

  13. Friction force experimental approach in High School Physics classes

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Alvarenga Monteiro

    2012-12-01

    Full Text Available http://dx.doi.org/10.5007/2175-7941.2012v29n3p1121 In this paper we propose and describe the performance of an experimental activity to address the concept of friction in High School Physics practical classes. We use a low-cost and simple construction device that enables the determination of the coefficient of static friction between two materials through three different procedures. The results were coherent, with small percentage deviation, which gives reliability to the activity and can stimulate discussions in class. The activity also allows greater contextualization of concepts that are usually discussed only theoretically, requiring a higher abstraction level of the students. This can stimulate discussions and greater interaction between teacher and students.

  14. "CLASS APPROACH" AND "PROLETARIAN CHARACTER" OF RUSSIAN REVOLUTION OF 1917

    Directory of Open Access Journals (Sweden)

    Эдуард Эдуардович Шульц

    2014-12-01

    Full Text Available Study of the problem of “class character” of 1917’ revolution and competency of the term “proletarian revolution”. The author considers questions of participation of various social groups in the Russian revolution, draws analogies of social composition of previous revolutions, considers the principle of “proletarian revolution”, as an ideology element for positioning of Bolsheviks and power capture. It is necessary to consider that an age, gender and national factor played much bigger role un Russian revolution than class factor. Revolution in Russia in many respects leaned on young generations which made more than a third of the population of the Russian Empire by 1917. In fight against tsarism separate calculation was based on the non-russian population and national suburbs of the empire. The special role in the Russian revolution was played by the peasantry. Revolution happened in the capital (in two capitals in Russia, the peasantry remained indifferent to revolution while Bolsheviks didn't begin to take away from them the food violently. This period:(summer - fall of 1919 became the time of peak of the Civil war. However return of landowners and their claim for property of the land forced peasants to turn bayonets for revolution and the earth and, eventually, to provide to Bolsheviks a victory in the Civil war.

  15. Neural Network Control of CSTR for Reversible Reaction Using Reverence Model Approach

    Directory of Open Access Journals (Sweden)

    Duncan ALOKO

    2007-01-01

    Full Text Available In this work, non-linear control of CSTR for reversible reaction is carried out using Neural Network as design tool. The Model Reverence approach in used to design ANN controller. The idea is to have a control system that will be able to achieve improvement in the level of conversion and to be able to track set point change and reject load disturbance. We use PID control scheme as benchmark to study the performance of the controller. The comparison shows that ANN controller out perform PID in the extreme range of non-linearity.This paper represents a preliminary effort to design a simplified neutral network control scheme for a class of non-linear process. Future works will involve further investigation of the effectiveness of thin approach for the real industrial chemical process

  16. A Synthesis of Behavioral and Communication Approaches to Child Rearing for Parenting Skills Classes. Practicum II.

    Science.gov (United States)

    Silverman, Marvin

    This report describes the design, implementation and evaluation of a class on effective parenting skills that combined behavioral and communication based (client-centered and Adlerian) approaches to child rearing. Seventeen parents of elementary school age children attended the class; twelve parents attended five or more sessions. The class…

  17. Managing Active Learning Processes in Large First Year Physics Classes: The Advantages of an Integrated Approach

    Directory of Open Access Journals (Sweden)

    Michael J. Drinkwater

    2014-09-01

    Full Text Available Turning lectures into interactive, student-led question and answer sessions is known to increase learning, but enabling interaction in a large class seems aninsurmountable task. This can discourage adoption of this new approach – who has time to individualize responses, address questions from over 200 students and encourage active participation in class? An approach adopted by a teaching team in large first-year classes at a research-intensive university appears to provide a means to do so. We describe the implementation of active learning strategies in a large first-year undergraduate physics unit of study, replacing traditional, content-heavy lectures with an integrated approach to question-driven learning. A key feature of our approach is that it facilitates intensive in-class discussions by requiring students to engage in preparatory reading and answer short written quizzes before every class. The lecturer uses software to rapidly analyze the student responses and identify the main issues faced by the students before the start of each class. We report the success of the integration of student preparation with this analysis and feedback framework, and the impact on the in-class discussions. We also address some of the difficulties commonly experienced by staff preparing for active learning classes.

  18. A Latent Class Approach to Examining Forms of Peer Victimization

    Science.gov (United States)

    Bradshaw, Catherine P.; Waasdorp, Tracy E.; O'Brennan, Lindsey M.

    2013-01-01

    There is growing interest in gender differences in the experience of various forms of peer victimization; however, much of the work to date has used traditional variable-centered approaches by focusing on scales or individual forms of victimization in isolation. The current study explored whether there were discrete groups of adolescents who…

  19. Participatory development: an approach sensitive to class and gender.

    Science.gov (United States)

    Connell, D

    1997-08-01

    This article begins by presenting development experience gained in the Indonesian province of Irian Jaya as a means of highlighting the centrality of popular participation to the development process. Important lessons from the ongoing development work in Irian Jaya were that it is not sufficient to consult beneficiaries and then act on their behalf or to engage in a development process unless the participants understand the project's conceptual orientation and language and have the tools to assess their needs and options for constructive change effectively. Also, developers must supply participants with information about the larger economic and political context in which they are operating. The article continues with an exploration of the ways in which a focus on class and gender raises participatory development to a new level. Constraints on transformative participation are then defined as 1) the political conditions and power structures existing in the country and community, 2) administrative opposition, 3) sociocultural impediments, and 4) limitations imposed by daily life. While it may be impossible to avoid the effects of such constraints, development agents can help villagers anticipate their impact and support efforts to cope with them. Participatory development challenges the status quo by enhancing economic equity and social equality and, if effective, will engender opposition, especially when a large amount of funding is at stake. Opposition can take many forms, including ridicule or resistance and can get personal. The demand to produce quick results also creates restraints on development agents. It is concluded that the development agent must engage key sectors of the local population in the development process and nurture this participation. Development agents should act as facilitators rather than independent initiators telling people what is best for them. Development agents must become very familiar with the community to earn the trust that is

  20. Teaching Reading Skills in the EFL Class. A Practical Approach

    Directory of Open Access Journals (Sweden)

    Ovidiu Aniculaese

    2008-11-01

    Full Text Available Teaching reading first requires careful consideration regarding the choice of text that may yield the richest and most relevant exposure to language. Reading is most effective through a top-down approach and students must develop speed and efficiency by avoiding sub-vocalisation, focusing on key words and taking in clusters of meaning at one time. Pre-reading for gist speeds up understanding by discovery of the text’s structure and of the type of paragraph in question. Explanatory paraphrasing and context clues should be sought when difficult vocabulary is encountered. Correct answers to comprehension questions may come from an awareness of the range of distracters possible, the writer’s attitude and the focus of the question.

  1. Current and evolving approaches for improving the oral permeability of BCS Class III or analogous molecules.

    Science.gov (United States)

    Dave, Vivek S; Gupta, Deepak; Yu, Monica; Nguyen, Phuong; Varghese Gupta, Sheeba

    2017-02-01

    The Biopharmaceutics Classification System (BCS) classifies pharmaceutical compounds based on their aqueous solubility and intestinal permeability. The BCS Class III compounds are hydrophilic molecules (high aqueous solubility) with low permeability across the biological membranes. While these compounds are pharmacologically effective, poor absorption due to low permeability becomes the rate-limiting step in achieving adequate bioavailability. Several approaches have been explored and utilized for improving the permeability profiles of these compounds. The approaches include traditional methods such as prodrugs, permeation enhancers, ion-pairing, etc., as well as relatively modern approaches such as nanoencapsulation and nanosizing. The most recent approaches include a combination/hybridization of one or more traditional approaches to improve drug permeability. While some of these approaches have been extremely successful, i.e. drug products utilizing the approach have progressed through the USFDA approval for marketing; others require further investigation to be applicable. This article discusses the commonly studied approaches for improving the permeability of BCS Class III compounds.

  2. Surgical approach to TIR3 cytology class A prospective evaluation.

    Science.gov (United States)

    D'Alessandro, Nicola; Fasano, Giovanni Michele; Gilio, Francesco; Iside, Giovanni; Izzo, Maria Lucia; Loffredo, Andrea; Pinto, Margherita; Tramontano, Salvatore; Tramutola, Giuseppe; Citro, Giuseppe

    2014-01-01

    Fine-needle aspiration (FNA) has proven to be a safe and reliable method of investigation of thyroid lesions. Referencing to European classification, the associated risk of malignancy for TIR3, category reserved for aspirates that contain architectural and/or nuclear atypia, is variable in such studies. Aims of study were evaluating safety of surgical approach, assessing perioperative parameters surgically related, and estimating neoplastic rate for TIR3 group. A prospective evaluation of all TIR3 submitted to thyroidectomy was conducted by assessing histopatohologic results between January 2005 and December 2012, considering two categories, positive (neoplastic) and negative (not neoplastic) group. Intraoperative and complication rate was analyzed on TIR3 population. A total of 1514 total thyroidectomy was performed from 2005 to 2012: a total of 148 cases was considered on TIR3 group. Positive cases amounted to 64 (43.2%), 29 of which were carcinoma (19.6% of total population) and 35 of which were adenoma, while negative cases amounted to 84 (56.8%). Sensitivity and specificity of TIR3 as neoplastic screening was 43.2% and 82.1%. A total of 32 linfectomies was performed (21.6% of group). Positive group presented a significant lower mean age than negative group (42.1 vs 56.2 years) TIR3 group represents a various category, with probably different malignancy risk. Our results and neoplasms rate confirmed that surgical option should be gold standard, in order to define atypical pattern and reduce delayed diagnoses. Choice of a second FNA or a imaging monitoring should be adopted for specific condition. Fine-needle aspiration, Thyroidectomy, TIR3, Thyroid cancer.

  3. A controllability approach to the control of a class of chaotic systems

    International Nuclear Information System (INIS)

    Bowong, Samuel; Moukam Kakmeni, F.M.; Tchawoua, Clement; Abdus Salam International Centre for Theoretical Physics, Trieste

    2003-10-01

    In this paper the exponential control problem for a class of chaotic systems with affine dependence on the control is addressed and solved by the controllability approach. It is shown that the controllability approach in conjunction with Lyapunov Direct Method yields a promising way of controlling chaotic dynamics. The proposed strategy is an input-output control scheme which comprises a state estimator and an exponential linearizing feedback. The proposed output feedback controller allows chaos suppression and can be applied to a large class of chaotic systems. Explicit expression of the control time is given. Computer simulations confirm the feasibility of the proposed approach. (author)

  4. A Simple and Novel Approach to Delineating Stereochemistry of Electrocyclic Reactions

    Science.gov (United States)

    Mandal, Dipak K.

    2012-01-01

    The dynamic stereochemistry of electrocyclic reactions (a class of pericyclic reactions) stems from the operation of either conrotatory (con) or disrotatory (dis) mode of ring-closing and ring-opening processes. Difficulty is often encountered in depicting product stereochemistry resulting from such movements of substituents. A novel, simple,…

  5. A Data-Driven Sparse-Learning Approach to Model Reduction in Chemical Reaction Networks

    OpenAIRE

    Harirchi, Farshad; Khalil, Omar A.; Liu, Sijia; Elvati, Paolo; Violi, Angela; Hero, Alfred O.

    2017-01-01

    In this paper, we propose an optimization-based sparse learning approach to identify the set of most influential reactions in a chemical reaction network. This reduced set of reactions is then employed to construct a reduced chemical reaction mechanism, which is relevant to chemical interaction network modeling. The problem of identifying influential reactions is first formulated as a mixed-integer quadratic program, and then a relaxation method is leveraged to reduce the computational comple...

  6. A network dynamics approach to chemical reaction networks

    NARCIS (Netherlands)

    van der Schaft, Abraham; Rao, S.; Jayawardhana, B.

    2016-01-01

    A treatment of chemical reaction network theory is given from the perspective of nonlinear network dynamics, in particular of consensus dynamics. By starting from the complex-balanced assumption the reaction dynamics governed by mass action kinetics can be rewritten into a form which allows for a

  7. Pi-activated alcohols: an emerging class of alkylating agents for catalytic Friedel-Crafts reactions.

    Science.gov (United States)

    Bandini, Marco; Tragni, Michele

    2009-04-21

    The direct functionalization of aromatic compounds, via Friedel-Crafts alkylation reactions with alcohols, is one of the cornerstones in organic chemistry. The present emerging area deals with the recent advances in the use of pi-activated alcohols in the catalytic and stereoselective construction of benzylic stereocenters.

  8. A dynamical theory of incomplete fusion reactions: The breakup-fusion reaction approach

    International Nuclear Information System (INIS)

    Udagawa, T.

    1984-01-01

    A dynamical theory of partial fusion reactions is presented, which may fill the gap between direct and compound nuclear reaction theories. With the new theory one can calculate partial fusion taking place in three-body (and many more) channels reached via direct reactions, e.g., breakup and knockout reactions. The authors present first the results for the cross section for such reactions, taking as an example breakup followed by fusion. They then discuss a physical picture which emerges from their theory, namely that the partial fusion reactions, particularly of the massive-transfer type, take place in a so-called deep peripheral region. It is also shown that the deep peripheral character of such processes diminishes as the mass of the fused system decreases, so that the reactions essentially evolve to the usual peripheral character. Finally, comparisons are made of results of numerical calculations with experimental data, taking as an example the /sup 159/Tb(/sup 14/N,α) reaction with E/sub lab/ = 95 MeV

  9. A cellular automata approach to chemical reactions : 1 reaction controlled systems

    NARCIS (Netherlands)

    Korte, de A.C.J.; Brouwers, H.J.H.

    2013-01-01

    A direct link between the chemical reaction controlled (shrinking core) model and cellular automata, to study the dissolution of particles, is derived in this paper. Previous research on first and second order reactions is based on the concentration of the reactant. The present paper describes the

  10. Is the relativistic approach really useful to nuclear reactions?

    CERN Document Server

    Miyazaki, K

    2003-01-01

    We have reconsidered the non-relativistic distorted-wave t-matrix approximation (NR-DWTA) for proton knockout (p,2p) reaction using modern high-quality phenomenological optical potentials and NN t-matrix. We have calculated 40Ca(p,2p) reactions at T_LAB=200MeV and compared the results with the relativistic distorted-wave impulse approximation (RDWIA) calculations. It is found that the NR-DWTA is superior to the RDWIA in consistent description of the cross section and the analyzing power. An immediate relativistic extension of the DWIA to the nuclear reaction has a problem.

  11. An Ensemble Based Evolutionary Approach to the Class Imbalance Problem with Applications in CBIR

    Directory of Open Access Journals (Sweden)

    Aun Irtaza

    2018-03-01

    Full Text Available In order to lower the dependence on textual annotations for image searches, the content based image retrieval (CBIR has become a popular topic in computer vision. A wide range of CBIR applications consider classification techniques, such as artificial neural networks (ANN, support vector machines (SVM, etc. to understand the query image content to retrieve relevant output. However, in multi-class search environments, the retrieval results are far from optimal due to overlapping semantics amongst subjects of various classes. The classification through multiple classifiers generate better results, but as the number of negative examples increases due to highly correlated semantic classes, classification bias occurs towards the negative class, hence, the combination of the classifiers become even more unstable particularly in one-against-all classification scenarios. In order to resolve this issue, a genetic algorithm (GA based classifier comity learning (GCCL method is presented in this paper to generate stable classifiers by combining ANN with SVMs through asymmetric and symmetric bagging. The proposed approach resolves the classification disagreement amongst different classifiers and also resolves the class imbalance problem in CBIR. Once the stable classifiers are generated, the query image is presented to the trained model to understand the underlying semantic content of the query image for association with the precise semantic class. Afterwards, the feature similarity is computed within the obtained class to generate the semantic response of the system. The experiments reveal that the proposed method outperforms various state-of-the-art methods and significantly improves the image retrieval performance.

  12. On the Existence of a Free Boundary for a Class of Reaction-Diffusion Systems.

    Science.gov (United States)

    1982-02-01

    I. Diaz. "Soluciones con soporte compacto para alguno. problemas semilineales". Collect. Math. 30 (1979), 141-179. -26- [121 J. I. Diaz. Tecnica de ...supersoluciones locales para problemas estacionarios no lineales: applicacion al estudio de flujoe subsonicos. Memory of the Real Academia de Ciencias...nonlinearity, nonlinear boundary conditions, dead core set, chemical reactions Work Unit Number I - Applied Analysis (1) Seccion de Matematicas

  13. Implementation of 5E Inquiry Incorporated with Analogy Learning Approach to Enhance Conceptual Understanding of Chemical Reaction Rate for Grade 11 Students

    Science.gov (United States)

    Supasorn, Saksri; Promarak, Vinich

    2015-01-01

    The main purpose of this study was to enhance student understanding of the scientific concepts of chemical reaction rate. Forty-four grade 11 students were the target group. The treatment tools were seven learning plans of 5E inquiry incorporated with an analogy learning approach during 15 hours of class time. In each learning plan, the students…

  14. Effects of Brain-Based Learning Approach on Students' Motivation and Attitudes Levels in Science Class

    Science.gov (United States)

    Akyurek, Erkan; Afacan, Ozlem

    2013-01-01

    The purpose of the study was to examine the effect of brain-based learning approach on attitudes and motivation levels in 8th grade students' science classes. The main reason for examining attitudes and motivation levels, the effect of the short-term motivation, attitude shows the long-term effect. The pre/post-test control group research model…

  15. WOWW: A Solution Orientated Approach to Enhance Classroom Relationships and Behaviour within a Primary Three Class

    Science.gov (United States)

    Fernie, Lynne; Cubeddu, Daniela

    2016-01-01

    A Working on What Works (WOWW) approach was utilised over six sessions in a mainstream Scottish primary class to enhance classroom relationships and behaviours. The aim of the intervention was to manage everyday classroom problems within a natural classroom environment. WOWW incorporates positive psychology and implements a solution-focused…

  16. Laboratory approaches of nuclear reactions involved in primordial and stellar nucleosynthesis

    International Nuclear Information System (INIS)

    Rolfs, C.; California Inst. of Tech., Pasadena

    1986-01-01

    Laboratory-based studies of primordial and stellar nucleosynthesis are reviewed, with emphasis on the nuclear reactions induced by charged particles. The analytical approach used to investigate nuclear reactions associated with stellar reactions is described, as well as the experimental details and procedures used to investigate nuclear reactions induced by charged particles. The present knowledge of some of the key reactions involved in primordial nucleosynthesis is discussed, along with the progress and problems of nuclear reactions involved in the hydrogen and helium burning phases of a star. Finally, a description is given of new experimental techniques which might be useful for future experiments in the field of nuclear astrophysics. (U.K.)

  17. Approach to defining de minimis, intermediate, and other classes of radioactive waste

    International Nuclear Information System (INIS)

    Cohen, J.J.; Smith, C.F.

    1986-01-01

    This study has developed a framework within which the complete spectrum of radioactive wastes can be defined. An approach has been developed that reflects both concerns in the framework of a radioactive waste classification system. In this approach, the class of any radioactive waste stream is dependent on its degree of radioactivity and its persistence. To be consistent with conventional systems, four waste classes are defined. In increasing order of concern due to radioactivity and/or duration, these are: 1. De Minimis Wastes: This waste has such a low content of radioactive material that it can be considered essentially nonradioactive and managed according to its nonradiological characteristics. 2. Low-Level Waste (LLW): Maximum concentrations for wastes considered to be in this class are prescribed in 10CFR61 as wastes that can be disposed of by shallow land burial methods. 3. Intermediate Level Waste (ILW): This category defines a class of waste whose content exceeds class C (10CFR61) levels, yet does not pose a sufficient hazard to justify management as a high-level waste (i.e., permanent isolation by deep geologic disposal). 4. High-Level Waste: HLW poses the most serious management problem and requires the most restrictive disposal methods. It is defined in NWPA as waste derived from the reprocessing of nuclear fuel and/or as highly radioactive wastes that require permanent isolation

  18. Wave Packet Based Statistical Approach to Complex-Forming Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hua [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Chemistry and Chemical Biology

    2017-12-06

    Combustion represents a key chemical process in energy consumption in modern societies and a clear and comprehensive understanding of the elemental reactions in combustion is of great importance to a number of challenging areas such as engine efficiency and environmental protection. In this award, we proposed to develop new theoretical tools to understand elemental chemical processes in combustion environments. With the support of this DOE grant, we have made significant advances in developing new and more efficient and accurate algorithms to characterize reaction dynamics.

  19. Mannich reaction: A versatile and convenient approach to bioactive ...

    Indian Academy of Sciences (India)

    tions of multifaceted Mannich reaction in the synthesis of antimalarial, antitumour ..... R1, R2 = methyl, ethyl, n-propyl, n-butyl, (CH2)4, (CH2)2O(CH2)2, (CH2)5. R1 =H, R2 = Et or .... Kumbhare et al. reported zinc chloride cat- alyzed Mannich ...

  20. Bilateral sagittal split osteotomy: Surgery first approach for correction of skeletal Class II

    Directory of Open Access Journals (Sweden)

    Revathi Peddu

    2018-01-01

    Full Text Available Most of the skeletal malocclusions which require orthognathic surgeries are treated by traditional approach which requires time-consuming and unesthetic presurgical orthodontic phase. Surgery first approach (SFA avoids these disadvantages of the traditional approach. A 24-year-old female patient with skeletal and dental class II malocclusion due to retrognathic mandible was treated with SFA. Bilateral sagittal split osteotomy with mandibular advancement was done immediately after initial alignment and closure of the existing spaces in the maxillary arch. Angle's class I molar and canine relation was achieved after surgery. Bonding of the mandibular arch was done after 1 month of orthognathic surgery and treatment was completed within 13 months. A wrap-around retainer was placed in upper arch, and bonded lingual retainer was given in the lower arch.

  1. Study of Cold Fusion Reactions Using Collective Clusterization Approach

    Science.gov (United States)

    Kaur, Gurjit; Sandhu, Kirandeep; Sharma, Manoj K.

    2017-10-01

    Within the framework of the dynamical cluster decay model (DCM), the 1n evaporation cross-sections ({σ }1n) of cold fusion reactions (Pb and Bi targets) are calculated for {Z}{CN}=104-113 superheavy nuclei. The calculations are carried out in the fixed range of excitation energy {E}{CN}* =15+/- 1 {MeV}, so that the comparative analysis of reaction dynamics can be worked out. First of all, the fission barriers (B f ) and neutron separation energies ({S}1n) are estimated to account the decreasing cross-sections of cold fusion reactions. In addition to this, the importance of hot optimum orientations of β 2i-deformed nuclei over cold one is explored at fixed angular momentum and neck-length parameters. The hot optimum orientations support all the target-projectile (t,p) combinations, which are explored experimentally in the cold fusion reactions. Some new target-projectile combinations are also predicted for future exploration. Further, the 1n cross-sections are addressed for {Z}{CN}=104-113 superheavy nuclei at comparable excitation energies which show the decent agrement with experimental data upto {Z}{CN}=109 nuclei. Finally, to understand the dynamics of higher-Z superheavy nuclei, the cross-sections are also calculated at maximum available energies around the Coulomb barrier and the effect of non-sticking moment of inertia ({I}{NS}) is also investigated at these energies. Supported by the Council of Scientific and Industrial Research (CSIR), in the Form of Research Project Grant No. 03(1341)/15/EMR-II, and to DST, New Delhi, for INSPIRE-Fellowship Grant No. DST/INSPIRE/03/2015/000199

  2. Effect of Conceptual Change Approach on Students' Understanding of Reaction Rate Concepts

    Science.gov (United States)

    Kingir, Sevgi; Geban, Omer

    2012-01-01

    The purpose of the present study was to investigate the effect of conceptual change text oriented instruction compared to traditional instruction on 10th grade students' understanding of reaction rate concepts. 45 students from two classes of the same teacher in a public high school participated in this study. Students in the experimental group…

  3. Practice expenses in the MFS (Medicare fee schedule): the service-class approach.

    Science.gov (United States)

    Latimer, E A; Kane, N M

    1995-01-01

    The practice expense component of the Medicare fee schedule (MFS), which is currently based on historical charges and rewards physician procedures at the expense of cognitive services, is due to be changed by January 1, 1998. The Physician Payment Review Commission (PPRC) and others have proposed microcosting direct costs and allocating all indirect costs on a common basis, such as physician time or work plus direct costs. Without altering the treatment of direct costs, the service-class approach disaggregates indirect costs into six practice function costs. The practice function costs are then allocated to classes of services using cost-accounting and statistical methods. This approach would make the practice expense component more resource-based than other proposed alternatives.

  4. Alexithymia and psychosocial problems among Italian preadolescents. A latent class analysis approach.

    Science.gov (United States)

    Mannarini, Stefania; Balottin, Laura; Toldo, Irene; Gatta, Michela

    2016-10-01

    The study, conducted on Italian preadolscents aged 11 to 13 belonging to the general population, aims to investigate the relationship between the emotional functioning, namely, alexithymia, and the risk of developing behavioral and emotional problems measured using the Strength and Difficulty Questionnaire. The latent class analysis approach allowed to identify two latent variables, accounting for the internalizing (emotional symptoms and difficulties in emotional awareness) and for the externalizing problems (conduct problems and hyperactivity, problematic relationships with peers, poor prosocial behaviors and externally oriented thinking). The two latent variables featured two latent classes: the difficulty in dealing with problems and the strength to face problems that was representative of most of the healthy participants with specific gender differences. Along with the analysis of psychopathological behaviors, the study of resilience and strengths can prove to be a key step in order to develop valuable preventive approaches to tackle psychiatric disorders. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  5. Assessment of tautomer distribution using the condensed reaction graph approach

    Science.gov (United States)

    Gimadiev, T. R.; Madzhidov, T. I.; Nugmanov, R. I.; Baskin, I. I.; Antipin, I. S.; Varnek, A.

    2018-03-01

    We report the first direct QSPR modeling of equilibrium constants of tautomeric transformations (logK T ) in different solvents and at different temperatures, which do not require intermediate assessment of acidity (basicity) constants for all tautomeric forms. The key step of the modeling consisted in the merging of two tautomers in one sole molecular graph ("condensed reaction graph") which enables to compute molecular descriptors characterizing entire equilibrium. The support vector regression method was used to build the models. The training set consisted of 785 transformations belonging to 11 types of tautomeric reactions with equilibrium constants measured in different solvents and at different temperatures. The models obtained perform well both in cross-validation (Q2 = 0.81 RMSE = 0.7 logK T units) and on two external test sets. Benchmarking studies demonstrate that our models outperform results obtained with DFT B3LYP/6-311 ++ G(d,p) and ChemAxon Tautomerizer applicable only in water at room temperature.

  6. Case Studies of Interactive Whole-Class Teaching in Primary Science: Communicative approach and pedagogic purposes

    Science.gov (United States)

    McMahon, Kendra

    2012-07-01

    By developing two case studies of expert teaching in action, this study aimed to develop knowledge of talk in whole-class teaching in UK primary science lessons and understand this in relation to both the teachers' interpretations and sociocultural theoretical frameworks. Lessons were observed and video-recorded and the teachers engaged in video-stimulated-reflective dialogue to capture participants' reflections upon their own pedagogic purposes and interactions in the classroom. The analytic framework was developed at three levels: sequence of lessons, lesson, and episode. For each episode, the 'communicative approach' and teaching purposes were recorded. Transcripts were developed for fine grain analysis of selected episodes and a quantitative analysis was undertaken of the use of communicative approaches. Findings exemplify how different communicative approaches were used by the case-study teachers for different pedagogical purposes at different points in the sequence of lessons, contributing to primary teachers' repertoire for planning and practice. The initial elicitation of children's ideas can be understood as pooling them to enhance multivoicedness and develop a shared resource for future dialogues. Whole-class talk can support univocality by rehearsing procedural knowledge and exploring the meanings of scientific terminology. Identifying salient features of phenomena in the context of the whole-class marks them as significant as shared knowledge but valuing other observations extends the multivoicedness of the discourse.

  7. Is there a nonadherent subtype of hypertensive patient? A latent class analysis approach

    Directory of Open Access Journals (Sweden)

    Ranak B Trivedi

    2010-07-01

    Full Text Available Ranak B Trivedi1, Brian J Ayotte2, Carolyn T Thorpe3, David Edelman4, Hayden B Bosworth51Northwest Health Services Research and Development Service Center of Excellence, VA Puget Sound Health Care System, Seattle, Washington; 2Boston VA Health Care System, Boston, Massachusetts; 3Department of Population Health Sciences, University of Wisconsin, Madison, Wisconsin; 4Department of Medicine, Duke University Medical Center, Durham, North Carolina; 5Research Professor, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USAAbstract: To determine subtypes of adherence, 636 hypertensive patients (48% White, 34% male reported adherence to medications, diet, exercise, smoking, and home blood pressure monitoring. A latent class analysis approach was used to identify subgroups that adhere to these five self-management behaviors. Fit statistics suggested two latent classes. The first class (labeled “more adherent” included patients with greater probability of adhering to ­recommendations compared with the second class (labeled “less adherent” with regard to nonsmoking (97.7% versus 76.3%, medications (75.5% versus 49.5%, diet (70.7% versus 46.9%, exercise (63.4% versus 27.2%, and blood pressure monitoring (32% versus 3.4%. Logistic regression analyses used to characterize the two classes showed that “more adherent” participants were more likely to report full-time employment, adequate income, and better emotional and physical well-being. Results suggest the presence of a less adherent subtype of hypertensive patients. Behavioral interventions designed to improve adherence might best target these at-risk patients for greater treatment efficiency.Keywords: adherence, hypertension, latent class analysis, self-management

  8. Fat versus Thin Threading Approach on GPUs: Application to Stochastic Simulation of Chemical Reactions

    KAUST Repository

    Klingbeil, Guido; Erban, Radek; Giles, Mike; Maini, Philip K.

    2012-01-01

    We explore two different threading approaches on a graphics processing unit (GPU) exploiting two different characteristics of the current GPU architecture. The fat thread approach tries to minimize data access time by relying on shared memory and registers potentially sacrificing parallelism. The thin thread approach maximizes parallelism and tries to hide access latencies. We apply these two approaches to the parallel stochastic simulation of chemical reaction systems using the stochastic simulation algorithm (SSA) by Gillespie [14]. In these cases, the proposed thin thread approach shows comparable performance while eliminating the limitation of the reaction system's size. © 2006 IEEE.

  9. Fat versus Thin Threading Approach on GPUs: Application to Stochastic Simulation of Chemical Reactions

    KAUST Repository

    Klingbeil, Guido

    2012-02-01

    We explore two different threading approaches on a graphics processing unit (GPU) exploiting two different characteristics of the current GPU architecture. The fat thread approach tries to minimize data access time by relying on shared memory and registers potentially sacrificing parallelism. The thin thread approach maximizes parallelism and tries to hide access latencies. We apply these two approaches to the parallel stochastic simulation of chemical reaction systems using the stochastic simulation algorithm (SSA) by Gillespie [14]. In these cases, the proposed thin thread approach shows comparable performance while eliminating the limitation of the reaction system\\'s size. © 2006 IEEE.

  10. Statistical bootstrap approach to hadronic matter and multiparticle reactions

    International Nuclear Information System (INIS)

    Ilgenfritz, E.M.; Kripfganz, J.; Moehring, H.J.

    1977-01-01

    The authors present the main ideas behind the statistical bootstrap model and recent developments within this model related to the description of fireball cascade decay. Mathematical methods developed in this model might be useful in other phenomenological schemes of strong interaction physics; they are described in detail. The present status of applications of the model to various hadronic reactions is discussed. When discussing the relations of the statistical bootstrap model to other models of hadron physics the authors point out possibly fruitful analogies and dynamical mechanisms which are modelled by the bootstrap dynamics under definite conditions. This offers interpretations for the critical temperature typical for the model and indicates futher fields of application. (author)

  11. Classification of cancerous cells based on the one-class problem approach

    Science.gov (United States)

    Murshed, Nabeel A.; Bortolozzi, Flavio; Sabourin, Robert

    1996-03-01

    One of the most important factors in reducing the effect of cancerous diseases is the early diagnosis, which requires a good and a robust method. With the advancement of computer technologies and digital image processing, the development of a computer-based system has become feasible. In this paper, we introduce a new approach for the detection of cancerous cells. This approach is based on the one-class problem approach, through which the classification system need only be trained with patterns of cancerous cells. This reduces the burden of the training task by about 50%. Based on this approach, a computer-based classification system is developed, based on the Fuzzy ARTMAP neural networks. Experimental results were performed using a set of 542 patterns taken from a sample of breast cancer. Results of the experiment show 98% correct identification of cancerous cells and 95% correct identification of non-cancerous cells.

  12. A Remote Sensing Approach to Estimate Vertical Profile Classes of Phytoplankton in a Eutrophic Lake

    Directory of Open Access Journals (Sweden)

    Kun Xue

    2015-10-01

    Full Text Available The extension and frequency of algal blooms in surface waters can be monitored using remote sensing techniques, yet knowledge of their vertical distribution is fundamental to determine total phytoplankton biomass and understanding temporal variability of surface conditions and the underwater light field. However, different vertical distribution classes of phytoplankton may occur in complex inland lakes. Identification of the vertical profile classes of phytoplankton becomes the key and first step to estimate its vertical profile. The vertical distribution profile of phytoplankton is based on a weighted integral of reflected light from all depths and is difficult to determine by reflectance data alone. In this study, four Chla vertical profile classes (vertically uniform, Gaussian, exponential and hyperbolic were found to occur in three in situ vertical surveys (28 May, 19–24 July and 10–12 October in a shallow eutrophic lake, Lake Chaohu. We developed and validated a classification and regression tree (CART to determine vertical phytoplankton biomass profile classes. This was based on an algal bloom index (Normalized Difference algal Bloom Index, NDBI applied to both in situ remote sensing reflectance (Rrs and MODIS Rayleigh-corrected reflectance (Rrc data in combination with data of local wind speed. The results show the potential of retrieving Chla vertical profiles information from integrated information sources following a decision tree approach.

  13. Targeting implicit approach reactions to snack food in children; Effects on intake

    NARCIS (Netherlands)

    Folkvord, Frans; Veling, Harm; Hoeken, J.A.L.

    Objective: Implicit approach reactions to energy-dense snack food can facilitate unhealthy eating in children. Therefore, an experiment was conducted to test whether modifying implicit reactions to snack food by means of a go/no-go task can reduce consumption of this food. The effectiveness of this

  14. Class D management implementation approach of the first orbital mission of the Earth Venture series

    Science.gov (United States)

    Wells, James E.; Scherrer, John; Law, Richard; Bonniksen, Chris

    2013-09-01

    A key element of the National Research Council's Earth Science and Applications Decadal Survey called for the creation of the Venture Class line of low-cost research and application missions within NASA (National Aeronautics and Space Administration). One key component of the architecture chosen by NASA within the Earth Venture line is a series of self-contained stand-alone spaceflight science missions called "EV-Mission". The first mission chosen for this competitively selected, cost and schedule capped, Principal Investigator-led opportunity is the CYclone Global Navigation Satellite System (CYGNSS). As specified in the defining Announcement of Opportunity, the Principal Investigator is held responsible for successfully achieving the science objectives of the selected mission and the management approach that he/she chooses to obtain those results has a significant amount of freedom as long as it meets the intent of key NASA guidance like NPR 7120.5 and 7123. CYGNSS is classified under NPR 7120.5E guidance as a Category 3 (low priority, low cost) mission and carries a Class D risk classification (low priority, high risk) per NPR 8705.4. As defined in the NPR guidance, Class D risk classification allows for a relatively broad range of implementation strategies. The management approach that will be utilized on CYGNSS is a streamlined implementation that starts with a higher risk tolerance posture at NASA and that philosophy flows all the way down to the individual part level.

  15. Class D Management Implementation Approach of the First Orbital Mission of the Earth Venture Series

    Science.gov (United States)

    Wells, James E.; Scherrer, John; Law, Richard; Bonniksen, Chris

    2013-01-01

    A key element of the National Research Council's Earth Science and Applications Decadal Survey called for the creation of the Venture Class line of low-cost research and application missions within NASA (National Aeronautics and Space Administration). One key component of the architecture chosen by NASA within the Earth Venture line is a series of self-contained stand-alone spaceflight science missions called "EV-Mission". The first mission chosen for this competitively selected, cost and schedule capped, Principal Investigator-led opportunity is the CYclone Global Navigation Satellite System (CYGNSS). As specified in the defining Announcement of Opportunity, the Principal Investigator is held responsible for successfully achieving the science objectives of the selected mission and the management approach that he/she chooses to obtain those results has a significant amount of freedom as long as it meets the intent of key NASA guidance like NPR 7120.5 and 7123. CYGNSS is classified under NPR 7120.5E guidance as a Category 3 (low priority, low cost) mission and carries a Class D risk classification (low priority, high risk) per NPR 8705.4. As defined in the NPR guidance, Class D risk classification allows for a relatively broad range of implementation strategies. The management approach that will be utilized on CYGNSS is a streamlined implementation that starts with a higher risk tolerance posture at NASA and that philosophy flows all the way down to the individual part level.

  16. Multilevel latent class casemix modelling: a novel approach to accommodate patient casemix.

    Science.gov (United States)

    Gilthorpe, Mark S; Harrison, Wendy J; Downing, Amy; Forman, David; West, Robert M

    2011-03-01

    Using routinely collected patient data we explore the utility of multilevel latent class (MLLC) models to adjust for patient casemix and rank Trust performance. We contrast this with ranks derived from Trust standardised mortality ratios (SMRs). Patients with colorectal cancer diagnosed between 1998 and 2004 and resident in Northern and Yorkshire regions were identified from the cancer registry database (n = 24,640). Patient age, sex, stage-at-diagnosis (Dukes), and Trust of diagnosis/treatment were extracted. Socioeconomic background was derived using the Townsend Index. Outcome was survival at 3 years after diagnosis. MLLC-modelled and SMR-generated Trust ranks were compared. Patients were assigned to two classes of similar size: one with reasonable prognosis (63.0% died within 3 years), and one with better prognosis (39.3% died within 3 years). In patient class one, all patients diagnosed at stage B or C died within 3 years; in patient class two, all patients diagnosed at stage A, B or C survived. Trusts were assigned two classes with 51.3% and 53.2% of patients respectively dying within 3 years. Differences in the ranked Trust performance between the MLLC model and SMRs were all within estimated 95% CIs. A novel approach to casemix adjustment is illustrated, ranking Trust performance whilst facilitating the evaluation of factors associated with the patient journey (e.g. treatments) and factors associated with the processes of healthcare delivery (e.g. delays). Further research can demonstrate the value of modelling patient pathways and evaluating healthcare processes across provider institutions.

  17. Multilevel latent class casemix modelling: a novel approach to accommodate patient casemix

    Directory of Open Access Journals (Sweden)

    Forman David

    2011-03-01

    Full Text Available Abstract Background Using routinely collected patient data we explore the utility of multilevel latent class (MLLC models to adjust for patient casemix and rank Trust performance. We contrast this with ranks derived from Trust standardised mortality ratios (SMRs. Methods Patients with colorectal cancer diagnosed between 1998 and 2004 and resident in Northern and Yorkshire regions were identified from the cancer registry database (n = 24,640. Patient age, sex, stage-at-diagnosis (Dukes, and Trust of diagnosis/treatment were extracted. Socioeconomic background was derived using the Townsend Index. Outcome was survival at 3 years after diagnosis. MLLC-modelled and SMR-generated Trust ranks were compared. Results Patients were assigned to two classes of similar size: one with reasonable prognosis (63.0% died within 3 years, and one with better prognosis (39.3% died within 3 years. In patient class one, all patients diagnosed at stage B or C died within 3 years; in patient class two, all patients diagnosed at stage A, B or C survived. Trusts were assigned two classes with 51.3% and 53.2% of patients respectively dying within 3 years. Differences in the ranked Trust performance between the MLLC model and SMRs were all within estimated 95% CIs. Conclusions A novel approach to casemix adjustment is illustrated, ranking Trust performance whilst facilitating the evaluation of factors associated with the patient journey (e.g. treatments and factors associated with the processes of healthcare delivery (e.g. delays. Further research can demonstrate the value of modelling patient pathways and evaluating healthcare processes across provider institutions.

  18. Autonomous optical navigation using nanosatellite-class instruments: a Mars approach case study

    Science.gov (United States)

    Enright, John; Jovanovic, Ilija; Kazemi, Laila; Zhang, Harry; Dzamba, Tom

    2018-02-01

    This paper examines the effectiveness of small star trackers for orbital estimation. Autonomous optical navigation has been used for some time to provide local estimates of orbital parameters during close approach to celestial bodies. These techniques have been used extensively on spacecraft dating back to the Voyager missions, but often rely on long exposures and large instrument apertures. Using a hyperbolic Mars approach as a reference mission, we present an EKF-based navigation filter suitable for nanosatellite missions. Observations of Mars and its moons allow the estimator to correct initial errors in both position and velocity. Our results show that nanosatellite-class star trackers can produce good quality navigation solutions with low position (<300 {m}) and velocity (<0.15 {m/s}) errors as the spacecraft approaches periapse.

  19. On the implicit programming approach in a class of mathematical programs with equilibrium constraints

    Czech Academy of Sciences Publication Activity Database

    Outrata, Jiří; Červinka, Michal

    2009-01-01

    Roč. 38, 4B (2009), s. 1557-1574 ISSN 0324-8569 R&D Projects: GA ČR GA201/09/1957 Institutional research plan: CEZ:AV0Z10750506 Keywords : mathematical problem with equilibrium constraint * state constraints * implicit programming * calmness * exact penalization Subject RIV: BA - General Mathematics Impact factor: 0.378, year: 2009 http://library.utia.cas.cz/separaty/2010/MTR/outrata-on the implicit programming approach in a class of mathematical programs with equilibrium constraints.pdf

  20. Prediction of Protein Structural Class Based on Gapped-Dipeptides and a Recursive Feature Selection Approach

    Directory of Open Access Journals (Sweden)

    Taigang Liu

    2015-12-01

    Full Text Available The prior knowledge of protein structural class may offer useful clues on understanding its functionality as well as its tertiary structure. Though various significant efforts have been made to find a fast and effective computational approach to address this problem, it is still a challenging topic in the field of bioinformatics. The position-specific score matrix (PSSM profile has been shown to provide a useful source of information for improving the prediction performance of protein structural class. However, this information has not been adequately explored. To this end, in this study, we present a feature extraction technique which is based on gapped-dipeptides composition computed directly from PSSM. Then, a careful feature selection technique is performed based on support vector machine-recursive feature elimination (SVM-RFE. These optimal features are selected to construct a final predictor. The results of jackknife tests on four working datasets show that our method obtains satisfactory prediction accuracies by extracting features solely based on PSSM and could serve as a very promising tool to predict protein structural class.

  1. alpha,beta-unsaturated 2-acyl imidazoles as a practical class of dienophiles for the DNA-Based catalytic asymmetric diels-alder reaction in water

    NARCIS (Netherlands)

    Boersma, A.J.; Feringa, B.L.; Roelfes, G.

    2007-01-01

    alpha,beta-Unsaturated 2-acyl imidazoles are a novel and practical class of dienophiles for the DNA-based catalytic asymmetric Diels-Alder reaction in water. The Diels-Alder products are obtained with very high diastereoselectivities and enantioselectivities in the range of 83-98%. The catalytic

  2. Using a CBL Unit, a Temperature Sensor, and a Graphing Calculator to Model the Kinetics of Consecutive First-Order Reactions as Safe In-Class Demonstrations

    Science.gov (United States)

    Moore-Russo, Deborah A.; Cortes-Figueroa, Jose E.; Schuman, Michael J.

    2006-01-01

    The use of Calculator-Based Laboratory (CBL) technology, the graphing calculator, and the cooling and heating of water to model the behavior of consecutive first-order reactions is presented, where B is the reactant, I is the intermediate, and P is the product for an in-class demonstration. The activity demonstrates the spontaneous and consecutive…

  3. Reaction

    African Journals Online (AJOL)

    abp

    19 oct. 2017 ... Reaction to Mohamed Said Nakhli et al. concerning the article: "When the axillary block remains the only alternative in a 5 year old child". .... Bertini L1, Savoia G, De Nicola A, Ivani G, Gravino E, Albani A et al ... 2010;7(2):101-.

  4. Alternative approach for fire suppression of class A, B and C fires in gloveboxes

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberger, Mark S [Los Alamos National Laboratory; Tsiagkouris, James A [Los Alamos National Laboratory

    2011-02-10

    Department of Energy (DOE) Orders and National Fire Protection Association (NFPA) Codes and Standards require fire suppression in gloveboxes. Several potential solutions have been and are currently being considered at Los Alamos National Laboratory (LANL). The objective is to provide reliable, minimally invasive, and seismically robust fire suppression capable of extinguishing Class A, B, and C fires; achieve compliance with DOE and NFPA requirements; and provide value-added improvements to fire safety in gloveboxes. This report provides a brief summary of current approaches and also documents the successful fire tests conducted to prove that one approach, specifically Fire Foe{trademark} tubes, is capable of achieving the requirement to provide reliable fire protection in gloveboxes in a cost-effective manner.

  5. A generalized volumetric dispersion model for a class of two-phase separation/reaction: finite difference solutions

    Science.gov (United States)

    Siripatana, Chairat; Thongpan, Hathaikarn; Promraksa, Arwut

    2017-03-01

    This article explores a volumetric approach in formulating differential equations for a class of engineering flow problems involving component transfer within or between two phases. In contrast to conventional formulation which is based on linear velocities, this work proposed a slightly different approach based on volumetric flow-rate which is essentially constant in many industrial processes. In effect, many multi-dimensional flow problems found industrially can be simplified into multi-component or multi-phase but one-dimensional flow problems. The formulation is largely generic, covering counter-current, concurrent or batch, fixed and fluidized bed arrangement. It was also intended to use for start-up, shut-down, control and steady state simulation. Since many realistic and industrial operation are dynamic with variable velocity and porosity in relation to position, analytical solutions are rare and limited to only very simple cases. Thus we also provide a numerical solution using Crank-Nicolson finite difference scheme. This solution is inherently stable as tested against a few cases published in the literature. However, it is anticipated that, for unconfined flow or non-constant flow-rate, traditional formulation should be applied.

  6. Extension of a Kinetic-Theory Approach for Computing Chemical-Reaction Rates to Reactions with Charged Particles

    Science.gov (United States)

    Liechty, Derek S.; Lewis, Mark J.

    2010-01-01

    Recently introduced molecular-level chemistry models that predict equilibrium and nonequilibrium reaction rates using only kinetic theory and fundamental molecular properties (i.e., no macroscopic reaction rate information) are extended to include reactions involving charged particles and electronic energy levels. The proposed extensions include ionization reactions, exothermic associative ionization reactions, endothermic and exothermic charge exchange reactions, and other exchange reactions involving ionized species. The extensions are shown to agree favorably with the measured Arrhenius rates for near-equilibrium conditions.

  7. The Cascade-Exciton Approach to Nuclear Reactions. (Foundation and Achievements)

    International Nuclear Information System (INIS)

    Mashnik, S.G.

    1994-01-01

    The relativistic kinetic equations describing nuclear reactions at intermediate energies are obtained on the dynamical basis. These equations are analyzed and realized in several versions of the Cascade Exciton Model (CEM). The CEM assumes that reactions occur in three stages: the intranuclear cascade, pre-equilibrium and the evaporative ones. A large variety of experimental data on hadron- and photonuclear reactions in the bombarding energy range up to several GeV are analyzed in this approach. The contributions of different pion and photon absorption mechanisms and the relative role of different particle and photon production mechanisms in these reactions are estimated. The CEM describes adequately nuclear reactions at intermediate energies and has one of the best predictive powers as compared to other available modern models. 55 refs., 10 figs., 1 tab

  8. An Approach for a Synthetic CTL Vaccine Design against Zika Flavivirus Using Class I and Class II Epitopes Identified by Computer Modeling

    Directory of Open Access Journals (Sweden)

    Edecio Cunha-Neto

    2017-06-01

    Full Text Available The threat posed by severe congenital abnormalities related to Zika virus (ZKV infection during pregnancy has turned development of a ZKV vaccine into an emergency. Recent work suggests that the cytotoxic T lymphocyte (CTL response to infection is an important defense mechanism in response to ZKV. Here, we develop the rationale and strategy for a new approach to developing cytotoxic T lymphocyte (CTL vaccines for ZKV flavivirus infection. The proposed approach is based on recent studies using a protein structure computer model for HIV epitope selection designed to select epitopes for CTL attack optimized for viruses that exhibit antigenic drift. Because naturally processed and presented human ZKV T cell epitopes have not yet been described, we identified predicted class I peptide sequences on ZKV matching previously identified DNV (Dengue class I epitopes and by using a Major Histocompatibility Complex (MHC binding prediction tool. A subset of those met the criteria for optimal CD8+ attack based on physical chemistry parameters determined by analysis of the ZKV protein structure encoded in open source Protein Data File (PDB format files. We also identified candidate ZKV epitopes predicted to bind promiscuously to multiple HLA class II molecules that could provide help to the CTL responses. This work suggests that a CTL vaccine for ZKV may be possible even if ZKV exhibits significant antigenic drift. We have previously described a microsphere-based CTL vaccine platform capable of eliciting an immune response for class I epitopes in mice and are currently working toward in vivo testing of class I and class II epitope delivery directed against ZKV epitopes using the same microsphere-based vaccine.

  9. Combining choice experiments with psychometric scales to assess the social acceptability of wind energy projects: A latent class approach

    International Nuclear Information System (INIS)

    Strazzera, Elisabetta; Mura, Marina; Contu, Davide

    2012-01-01

    A choice experiment exercise is combined with psychometric scales in order: (1) to identify factors that explain support/opposition toward a wind energy development project; and (2) to assess (monetary) trade-offs between attributes of the project. A Latent Class estimator is fitted to the data, and different utility parameters are estimated, conditional on class allocation. It is found that the probability of class membership depends on specific psychometric variables. Visual impacts on valued sites are an important factor of opposition toward a project, and this effect is magnified when identity values are attached to the specific site, so much that no trade-off would be acceptable for a class of individuals characterized by strong place attachment. Conversely, other classes of individuals are willing to accept compensations, in form of private and/or public benefits. The distribution of benefits in the territory, and preservation of the option value related to the possible development of an archeological site, are important for a class of individuals concerned with the sustainability of the local economy. - Highlights: ► A Choice Experiment approach is used to assess acceptability of a wind farm project. ► Psychometric variables are used to model heterogeneity in a Latent Class model. ► No trade-off would be acceptable for a class of individuals. ► Another class of individuals is interested in private benefits. ► Other classes are interested in public benefits and sustainability of the development.

  10. A flexible latent class approach to estimating test-score reliability

    NARCIS (Netherlands)

    van der Palm, D.W.; van der Ark, L.A.; Sijtsma, K.

    2014-01-01

    The latent class reliability coefficient (LCRC) is improved by using the divisive latent class model instead of the unrestricted latent class model. This results in the divisive latent class reliability coefficient (DLCRC), which unlike LCRC avoids making subjective decisions about the best solution

  11. Healthy cooking classes at a children’s cancer hospital and patient/survivor summer camp: initial reactions and feasibility

    Science.gov (United States)

    Raber, Margaret; Crawford, Karla; Chandra, Joya

    2018-01-01

    Objective Childhood cancer survivors (CCS) have been shown to practice sub-optimal dietary intake and may benefit from nutrition interventions during and after treatment. Cooking classes have become popular for encouraging healthy eating behaviors in community-based programming and academic research, however, literature on teaching cooking classes in CCS is limited. The purpose of this study is to address the development and implementation of classes for CCS based on a recently developed framework of healthy cooking behavior. Design A conceptual framework was developed from a systematic literature review and used to guide healthy cooking classes for CCS in different settings. Setting One pediatric cancer hospital inpatient unit, one pediatric cancer in-hospital camp program and two off-site pediatric cancer summer camp programs. Subjects One hundred and eighty nine CCS of varying ages and thirteen parents of CCS. Results Seventeen classes were taught at camps and seven classes in the hospital inpatient unit. Healthy cooking classes based on the conceptual framework are feasible and were well received by CCS. Conclusions Cooking classes for CCS, both at the hospital and at camp, reinforced the principles of the conceptual framework. Future trials should assess the dietary and anthropometric impact of evidence-based healthy cooking classes in CCS. PMID:28463101

  12. Chaos control for a class of chaotic systems using PI-type state observer approach

    International Nuclear Information System (INIS)

    Jiang Guoping; Zheng Weixing

    2004-01-01

    In this paper, by using the PI-type state observer design approach and the characteristic of ergodicity of chaos, a new method is presented for controlling chaos, including the stabilization of unstable equilibrium points and set-point tracking, for a class of chaotic systems. Based on the theory of nonlinear ordinary differential equations, a simple criterion is derived for designing the controller gains for stabilization and tracking, in which control parameters can be selected via the pole placement technique of linear control theory. More importantly, this control method has a simple controller structure, high robustness against system parametric variations, and strong rejection of external constant disturbances. The method is applied to the chaotic Lorenz system for demonstration

  13. Novel error propagation approach for reducing H2S/O2 reaction mechanism

    International Nuclear Information System (INIS)

    Selim, H.; Gupta, A.K.; Sassi, M.

    2012-01-01

    A reduction strategy of hydrogen sulfide/oxygen reaction mechanism is conducted to simplify the detailed mechanism. Direct relation graph and error propagation methodology (DRGEP) has been used. A novel approach of direct elementary reaction error (DERE) has been developed in this study. The developed approach allowed for further reduction of the reaction mechanism. The reduced mechanism has been compared with the detailed mechanism under different conditions to emphasize its validity. The results obtained from the resulting reduced mechanism showed good agreement with that from the detailed mechanism. However, some discrepancies have been found for some species. Hydrogen and oxygen mole fractions showed the largest discrepancy of all combustion products. The reduced mechanism was also found to be capable of tracking the changes that occur in chemical kinetics through the change in reaction conditions. A comparison on the ignition delay time obtained from the reduced mechanism and previous experimental data showed good agreement. The reduced mechanism was used to track changes in mechanistic pathways of Claus reactions with the reaction progress.

  14. Open quantum system approach to the modeling of spin recombination reactions.

    Science.gov (United States)

    Tiersch, M; Steiner, U E; Popescu, S; Briegel, H J

    2012-04-26

    In theories of spin-dependent radical pair reactions, the time evolution of the radical pair, including the effect of the chemical kinetics, is described by a master equation in the Liouville formalism. For the description of the chemical kinetics, a number of possible reaction operators have been formulated in the literature. In this work, we present a framework that allows for a unified description of the various proposed mechanisms and the forms of reaction operators for the spin-selective recombination processes. On the basis of the concept that master equations can be derived from a microscopic description of the spin system interacting with external degrees of freedom, it is possible to gain insight into the underlying microscopic processes and develop a systematic approach toward determining the specific form of the reaction operator in concrete scenarios.

  15. Kinetics of subdiffusion-assisted reactions: non-Markovian stochastic Liouville equation approach

    International Nuclear Information System (INIS)

    Shushin, A I

    2005-01-01

    Anomalous specific features of the kinetics of subdiffusion-assisted bimolecular reactions (time-dependence, dependence on parameters of systems, etc) are analysed in detail with the use of the non-Markovian stochastic Liouville equation (SLE), which has been recently derived within the continuous-time random-walk (CTRW) approach. In the CTRW approach, subdiffusive motion of particles is modelled by jumps whose onset probability distribution function is of a long-tailed form. The non-Markovian SLE allows for rigorous describing of some peculiarities of these reactions; for example, very slow long-time behaviour of the kinetics, non-analytical dependence of the reaction rate on the reactivity of particles, strong manifestation of fluctuation kinetics showing itself in very slowly decreasing behaviour of the kinetics at very long times, etc

  16. A Systematic Approach for the Design and Analysis of Reaction-Separation Systems with Recycle

    DEFF Research Database (Denmark)

    Gani, Rafiqul; Jimenez, Edgar Ramirez

    2004-01-01

    This paper presents a methodology for a systematic model-based analysis and the results obtained from it for an integrated design and analysis of reaction-separation systems with recycle. The methodology (systematic approach) consists of three stages where stage 1 identifies the limiting values...

  17. Two Experiments to Approach the Boltzmann Factor: Chemical Reaction and Viscous Flow

    Science.gov (United States)

    Fazio, Claudio; Battaglia, Onofrio R.; Guastella, Ivan

    2012-01-01

    In this paper we discuss a pedagogical approach aimed at pointing out the role played by the Boltzmann factor in describing phenomena usually perceived as regulated by different mechanisms of functioning. Experimental results regarding some aspects of a chemical reaction and of the viscous flow of some liquids are analysed and described in terms…

  18. α-Bromodiazoacetamides – a new class of diazo compounds for catalyst-free, ambient temperature intramolecular C–H insertion reactions

    Directory of Open Access Journals (Sweden)

    Åsmund Kaupang

    2013-07-01

    Full Text Available In this work, we introduce a new class of halodiazocarbonyl compounds, α-halodiazoacetamides, which through a metal-free, ambient-temperature thermolysis perform intramolecular C–H insertions to produce α-halo-β-lactams. When carried out with α-bromodiazoacetamides bearing cyclic side chains, the thermolysis reaction affords bicyclic α-halo-β-lactams, in some cases in excellent yields, depending on the ring size and substitution pattern of the cyclic amide side chains.

  19. Preliminary study of oaklins, a new class of brick-red catechinpyrylium pigments resulting from the reaction between catechin and wood aldehydes.

    Science.gov (United States)

    Sousa, Carlos; Mateus, Nuno; Perez-Alonso, Joaquín; Santos-Buelga, Celestino; Freitas, Victor de

    2005-11-16

    Several structurally related pigments were found to result from the reaction between catechin and coniferaldehyde/sinapaldehyde extracted from oak wood. Their structures were tentatively identified by mass spectrometry, and their formation was studied in different pH and temperature conditions for several days. They were all found to have a characteristic catechinpyrylium core, thereby constituting a new class of compounds named as oaklins. One of the main oaklins was also detected in a commercial table red wine aged in oak barrels.

  20. Report of seminar on relativistic approach to nuclear reaction and nuclear structure

    International Nuclear Information System (INIS)

    1986-05-01

    A seminar on 'Relativistic Approach to Nuclear Reaction and Nuclear Structure' was held in 1985 at Osaka University. This booklet includes twenty-four reports given at the seminar, which deal with: Conventional Nonrelativistic Description of Nuclear Matter and Nuclear Spin-Orbit Interactions; Relativistic Approach to Nuclear Structure; Atomic and Molecular Structure Calculations; Electromagnetic Interaction in Nucleus and Relativistic Effect; Nuclear Magnetic Moment in the Relativistic Mean Field Theory, Effective Mass and Particle-Vibration Coupling in the Relativistic σ-ω Model; Gauge Invariance in Relativistic Many-Body Theory; Relativistic Description of Nucleon-Nucleon Interaction in Review; σ-Particle in NN Interaction; Nuclear Optical Potentials Based on the Brueckner-Hartree-Fock Approach; Elastic Backscattering and Optical Potential; Description of Intermediate-Energy Nuclear Reactions; Dirac Phenomenology at E(p) = 65 MeV; Relativistic Impulse Approximation; Reaction Studies with Intermediate Energy Deuterons at SATURNE; Folding Model for Intermediate-Energy Deutron Scattering; Folding Model for Polarized Deutron Scattering at 700 MeV; Dirac Approach Problems and a Different Viewpoint; Relativistic Approach and EMC Effect; Quasielastic Electron Scattering; Response Function of Quasielastic Electron Scattering; Relativistic Hartree Response Function for Quasielastic Electron Scattering on 12 C and 40 Ca; Backflow-, Retardation- and Relativistic Effects on the Longitudinal Response Function of Nuclear Matter; Pion-Photoproduction in the σ-ω Model. (Nogami, K.)

  1. First-Principles Approach to Model Electrochemical Reactions: Understanding the Fundamental Mechanisms behind Mg Corrosion

    Science.gov (United States)

    Surendralal, Sudarsan; Todorova, Mira; Finnis, Michael W.; Neugebauer, Jörg

    2018-06-01

    Combining concepts of semiconductor physics and corrosion science, we develop a novel approach that allows us to perform ab initio calculations under controlled potentiostat conditions for electrochemical systems. The proposed approach can be straightforwardly applied in standard density functional theory codes. To demonstrate the performance and the opportunities opened by this approach, we study the chemical reactions that take place during initial corrosion at the water-Mg interface under anodic polarization. Based on this insight, we derive an atomistic model that explains the origin of the anodic hydrogen evolution.

  2. Non-equilibrium statistical mechanical approach for describing heavy ion reactions

    International Nuclear Information System (INIS)

    Sventek, J.S.

    1979-01-01

    With the availability of heavy-ion projectiles (A > 4) at low to intermediate energies (4 < E/A < 10), products showing various stages of relaxation for certain macroscopic variables (center-of-mass energy, orbital angular momentum, etc.) were produced in various reactions. The distributions for these macroscopic variables showed a correlation between the stage of relaxation reached and the net amount of mass transfer which had occurred in the reaction. There was also evidence that there was an asymmetry in the number of net transfers necessary for complete relaxation between stripping ad pickup reactions. A model for describing the time-evolution of these reactions has been formulated, the keystone of which is a master-equation approach for describing the time-dependence of the mass-asymmetry. This, coupled with deterministic equations of motion for the other macroscopic coordinates in the reaction lead to calculated distributions which provide an excellent qualitative description of these reactions, and, in some cases, quantitatively reproduce the experimental data quite well

  3. Health status transitions in community-living elderly with complex care needs: a latent class approach.

    Science.gov (United States)

    Lafortune, Louise; Béland, François; Bergman, Howard; Ankri, Joël

    2009-02-03

    For older persons with complex care needs, accounting for the variability and interdependency in how health dimensions manifest themselves is necessary to understand the dynamic of health status. Our objective is to test the hypothesis that a latent classification can capture this heterogeneity in a population of frail elderly persons living in the community. Based on a person-centered approach, the classification corresponds to substantively meaningful groups of individuals who present with a comparable constellation of health problems. Using data collected for the SIPA project, a system of integrated care for frail older people (n = 1164), we performed latent class analyses to identify homogenous categories of health status (i.e. health profiles) based on 17 indicators of prevalent health problems (chronic conditions; depression; cognition; functional and sensory limitations; instrumental, mobility and personal care disability) Then, we conducted latent transition analyses to study change in profile membership over 2 consecutive periods of 12 and 10 months, respectively. We modeled competing risks for mortality and lost to follow-up as absorbing states to avoid attrition biases. We identified four health profiles that distinguish the physical and cognitive dimensions of health and capture severity along the disability dimension. The profiles are stable over time and robust to mortality and lost to follow-up attrition. The differentiated and gender-specific patterns of transition probabilities demonstrate the profiles' sensitivity to change in health status and unmasked the differential relationship of physical and cognitive domains with progression in disability. Our approach may prove useful at organization and policy levels where many issues call for classification of individuals into pragmatically meaningful groups. In dealing with attrition biases, our analytical strategy could provide critical information for the planning of longitudinal studies of aging

  4. Health status transitions in community-living elderly with complex care needs: a latent class approach

    Directory of Open Access Journals (Sweden)

    Béland François

    2009-02-01

    Full Text Available Abstract Background For older persons with complex care needs, accounting for the variability and interdependency in how health dimensions manifest themselves is necessary to understand the dynamic of health status. Our objective is to test the hypothesis that a latent classification can capture this heterogeneity in a population of frail elderly persons living in the community. Based on a person-centered approach, the classification corresponds to substantively meaningful groups of individuals who present with a comparable constellation of health problems. Methods Using data collected for the SIPA project, a system of integrated care for frail older people (n = 1164, we performed latent class analyses to identify homogenous categories of health status (i.e. health profiles based on 17 indicators of prevalent health problems (chronic conditions; depression; cognition; functional and sensory limitations; instrumental, mobility and personal care disability Then, we conducted latent transition analyses to study change in profile membership over 2 consecutive periods of 12 and 10 months, respectively. We modeled competing risks for mortality and lost to follow-up as absorbing states to avoid attrition biases. Results We identified four health profiles that distinguish the physical and cognitive dimensions of health and capture severity along the disability dimension. The profiles are stable over time and robust to mortality and lost to follow-up attrition. The differentiated and gender-specific patterns of transition probabilities demonstrate the profiles' sensitivity to change in health status and unmasked the differential relationship of physical and cognitive domains with progression in disability. Conclusion Our approach may prove useful at organization and policy levels where many issues call for classification of individuals into pragmatically meaningful groups. In dealing with attrition biases, our analytical strategy could provide critical

  5. Investigating the Cellular and Metabolic Responses of World-Class Canoeists Training: A Sportomics Approach

    Directory of Open Access Journals (Sweden)

    Wagner Santos Coelho

    2016-11-01

    Full Text Available (1 Background: We have been using the Sportomics approach to evaluate biochemical and hematological changes in response to exercise. The aim of this study was to evaluate the metabolic and hematologic responses of world-class canoeists during a training session; (2 Methods: Blood samples were taken at different points and analyzed for their hematological properties, activities of selected enzymes, hormones, and metabolites; (3 Results: Muscle stress biomarkers were elevated in response to exercise which correlated with modifications in the profile of white blood cells, where a leukocyte rise was observed after the canoe session. These results were accompanied by an increase in other exercise intensity parameters such as lactatemia and ammonemia. Adrenocorticotropic hormone and cortisol increased during the exercise sessions. The acute rise in both erythrocytes and white blood profile were probably due to muscle cell damage, rather than hepatocyte integrity impairment; (4 Conclusion: The cellular and metabolic responses found here, together with effective nutrition support, are crucial to understanding the effects of exercise in order to assist in the creation of new training and recovery planning. Also we show that Sportomics is a primal tool for training management and performance improvement, as well as to the understanding of metabolic response to exercise.

  6. Unified path integral approach to theories of diffusion-influenced reactions

    Science.gov (United States)

    Prüstel, Thorsten; Meier-Schellersheim, Martin

    2017-08-01

    Building on mathematical similarities between quantum mechanics and theories of diffusion-influenced reactions, we develop a general approach for computational modeling of diffusion-influenced reactions that is capable of capturing not only the classical Smoluchowski picture but also alternative theories, as is here exemplified by a volume reactivity model. In particular, we prove the path decomposition expansion of various Green's functions describing the irreversible and reversible reaction of an isolated pair of molecules. To this end, we exploit a connection between boundary value and interaction potential problems with δ - and δ'-function perturbation. We employ a known path-integral-based summation of a perturbation series to derive a number of exact identities relating propagators and survival probabilities satisfying different boundary conditions in a unified and systematic manner. Furthermore, we show how the path decomposition expansion represents the propagator as a product of three factors in the Laplace domain that correspond to quantities figuring prominently in stochastic spatially resolved simulation algorithms. This analysis will thus be useful for the interpretation of current and the design of future algorithms. Finally, we discuss the relation between the general approach and the theory of Brownian functionals and calculate the mean residence time for the case of irreversible and reversible reactions.

  7. Neutron-induced reactions on U and Th - A new approach via AMS

    International Nuclear Information System (INIS)

    Wallner, A.; Capote, R.; Christl, M.; Fifield, L.K.; Srncik, M.; Tims, S.; Hotchkis, M.; Krasa, A.; Lachner, J.; Lippold, J.; Plompen, A.; Semkova, V.; Steier, P.; Winkler, S.

    2014-01-01

    Recent studies exhibit discrepancies at keV and MeV energies between major nuclear data libraries for 238 U(n,γ), 232 Th(n,γ) and also for (n,xn) reactions. We have extended our initial (n,γ) measurements on 235,238 U to higher neutron energies and to additional reaction channels. Neutron-induced reactions on 232 Th and 238 U were measured by a combination of the activation technique and atom counting of the reaction products using accelerator mass spectrometry (AMS). Natural thorium and uranium samples were activated with quasi-monoenergetic neutrons at IRMM. Neutron capture data were produced for neutron energies between 0.5 and 5 MeV. Fast neutron-induced reactions were studied in the energy range from 17 to 22 MeV. Preliminary data indicate a fair agreement with data libraries; however at the lower band of existing data. This approach represents a complementary method to on-line particle detection techniques and also to conventional decay counting. (authors)

  8. The In Situ Enzymatic Screening (ISES) Approach to Reaction Discovery and Catalyst Identification.

    Science.gov (United States)

    Swyka, Robert A; Berkowitz, David B

    2017-12-14

    The importance of discovering new chemical transformations and/or optimizing catalytic combinations has led to a flurry of activity in reaction screening. The in situ enzymatic screening (ISES) approach described here utilizes biological tools (enzymes/cofactors) to advance chemistry. The protocol interfaces an organic reaction layer with an adjacent aqueous layer containing reporting enzymes that act upon the organic reaction product, giving rise to a spectroscopic signal. ISES allows the experimentalist to rapidly glean information on the relative rates of a set of parallel organic/organometallic reactions under investigation, without the need to quench the reactions or draw aliquots. In certain cases, the real-time enzymatic readout also provides information on sense and magnitude of enantioselectivity and substrate specificity. This article contains protocols for single-well (relative rate) and double-well (relative rate/enantiomeric excess) ISES, in addition to a colorimetric ISES protocol and a miniaturized double-well procedure. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  9. "Cleaning" the Surface of Hydroxyapatite Nanorods by a Reaction-Dissolution Approach.

    Science.gov (United States)

    Cao, Binrui; Yang, Mingying; Wang, Lin; Xu, Hong; Zhu, Ye; Mao, Chuanbin

    2015-10-21

    Synthetic nanoparticles are always terminated with coating molecules, which are often cytotoxic and not desired in biomedicine. Here we propose a novel reaction-dissolution approach to remove the cytotoxic coating molecules. A two-component solution is added to the nanoparticle solution; one component reacts with the coating molecules to form a salt whereas another is a solvent for dissolving and thus removing the salt. As a proof of concept, this work uses a NaOH-ethanol solution to remove the cytotoxic linoleic acid molecules coated on the hydroxyapatite nanorods (HAP-NRs). The removal of the coating molecules not only significantly improves the biocompatibility of HAP-NRs but also enables their oriented attachment into tightly-bound superstructures, which mimic the organized HAP crystals in bone and enamel and can promote the osteogenic differentiation of mesenchymal stem cells. Our reaction-dissolution approach can be extended to the surface "cleaning" of other nanomaterials.

  10. A blended learning approach for teaching computer programming: design for large classes in Sub-Saharan Africa

    Science.gov (United States)

    Bayu Bati, Tesfaye; Gelderblom, Helene; van Biljon, Judy

    2014-01-01

    The challenge of teaching programming in higher education is complicated by problems associated with large class teaching, a prevalent situation in many developing countries. This paper reports on an investigation into the use of a blended learning approach to teaching and learning of programming in a class of more than 200 students. A course and learning environment was designed by integrating constructivist learning models of Constructive Alignment, Conversational Framework and the Three-Stage Learning Model. Design science research is used for the course redesign and development of the learning environment, and action research is integrated to undertake participatory evaluation of the intervention. The action research involved the Students' Approach to Learning survey, a comparative analysis of students' performance, and qualitative data analysis of data gathered from various sources. The paper makes a theoretical contribution in presenting a design of a blended learning solution for large class teaching of programming grounded in constructivist learning theory and use of free and open source technologies.

  11. A Multinomial Logit Approach to Estimating Regional Inventories by Product Class

    Science.gov (United States)

    Lawrence Teeter; Xiaoping Zhou

    1998-01-01

    Current timber inventory projections generally lack information on inventory by product classes. Most models available for inventory projection and linked to supply analyses are limited to projecting aggregate softwood and hardwood. The objective of this research is to develop a methodology to distribute the volume on each FIA survey plot to product classes and...

  12. Transformation of Teacher Practice Using Mobile Technology with One-to-One Classes: M-Learning Pedagogical Approaches

    Science.gov (United States)

    Lindsay, Lucie

    2016-01-01

    The rapid global uptake of mobile technology is reflected in pioneering New Zealand schools. Teachers of classes where each student uses a mobile device were surveyed on how frequently they use various mobile learning activities and asked to describe the new pedagogical opportunities it offers. The teachers' m-learning pedagogical approaches and…

  13. Meeting the latest qualification requirements for Class 1E protection system equipment: a practical approach

    International Nuclear Information System (INIS)

    Daigle, R.P.; Breen, R.J.

    1977-01-01

    The requirements for qualifying Class 1E equipment for Nuclear Power Generating Stations were significantly revised in 1974 and 1975. These new requirements reflect the desire of the industry to provide improved methods of determining the qualification of this vital equipment. The revised standards do, in fact, meet these industry goals in a generally acceptable manner. The Nuclear Regulatory Commission is presently requiring utilities to comply with these revised standards and regulatory guides in order to obtain the necessary permits. Manufacturers are developing and implementing programs to comply with the new requirements. One of the more difficult new requirements of qualification is aging to achieve advanced life condition. The objectives and methods described for aging are difficult for much of the equipment within the Protection System. The use of thermal and vibrational techniques to simulate aging is valid for some components (i.e., capacitors, transistors, cable and/or motor insulation) but may be neither valid nor practical for many items (e.g., complete instrument systems, etc.). A seemingly obvious approach, although rarely followed, in regarding new or revised standards is to refrain from making any type of commitment until the standards are thoroughly understood. Often too hasty a decision is made by a utility (concerned about licensing) or a manufacturer (concerned about being competitive) to commit to new requirements. Consequently, the broad range of interpretations that usually develops for a given set of requirements may result in difficult relations between organizations. This paper deals with solutions for qualification in a practical sense, with emphasis on the aging issue and does not elaborate on seismic qualification

  14. Perceived risk associated with ecstasy use: a latent class analysis approach

    Science.gov (United States)

    Martins, SS; Carlson, RG; Alexandre, PK; Falck, RS

    2011-01-01

    This study aims to define categories of perceived health problems among ecstasy users based on observed clustering of their perceptions of ecstasy-related health problems. Data from a community sample of ecstasy users (n=402) aged 18 to 30, in Ohio, was used in this study. Data was analyzed via Latent Class Analysis (LCA) and Regression. This study identified five different subgroups of ecstasy users based on their perceptions of health problems they associated with their ecstasy use. Almost one third of the sample (28.9%) belonged to a class with “low level of perceived problems” (Class 4). About one fourth (25.6%) of the sample (Class 2), had high probabilities of “perceiving problems on sexual-related items”, but generally low or moderate probabilities of perceiving problems in other areas. Roughly one-fifth of the sample (21.1%, Class 1) had moderate probabilities of perceiving ecstasy health-related problems in all areas. A small proportion of respondents (11.9%, Class 5) had high probabilities of reporting “perceived memory and cognitive problems, and of perceiving “ecstasy related-problems in all areas” (12.4%, Class 3). A large proportion of ecstasy users perceive either low or moderate risk associated with their ecstasy use. It is important to further investigate whether lower levels of risk perception are associated with persistence of ecstasy use. PMID:21296504

  15. A novel approach to sports concussion assessment: Computerized multilimb reaction times and balance control testing.

    Science.gov (United States)

    Vartiainen, Matti V; Holm, Anu; Lukander, Jani; Lukander, Kristian; Koskinen, Sanna; Bornstein, Robert; Hokkanen, Laura

    2016-01-01

    Mild traumatic brain injuries (MTBI) or concussions often result in problems with attention, executive functions, and motor control. For better identification of these diverse problems, novel approaches integrating tests of cognitive and motor functioning are needed. The aim was to characterize minor changes in motor and cognitive performance after sports-related concussions with a novel test battery, including balance tests and a computerized multilimb reaction time test. The cognitive demands of the battery gradually increase from a simple stimulus response to a complex task requiring executive attention. A total of 113 male ice hockey players (mean age = 24.6 years, SD = 5.7) were assessed before a season. During the season, nine concussed players were retested within 36 hours, four to six days after the concussion, and after the season. A control group of seven nonconcussed players from the same pool of players with comparable demographics were retested after the season. Performance was measured using a balance test and the Motor Cognitive Test battery (MotCoTe) with multilimb responses in simple reaction, choice reaction, inhibition, and conflict resolution conditions. The performance of the concussed group declined at the postconcussion assessment compared to both the baseline measurement and the nonconcussed controls. Significant changes were observed in the concussed group for the multilimb choice reaction and inhibition tests. Tapping and balance showed a similar trend, but no statistically significant difference in performance. In sports-related concussions, complex motor tests can be valuable additions in assessing the outcome and recovery. In the current study, using subtasks with varying cognitive demands, it was shown that while simple motor performance was largely unaffected, the more complex tasks induced impaired reaction times for the concussed subjects. The increased reaction times may reflect the disruption of complex and integrative cognitive

  16. Fatal and serious road crashes involving young New Zealand drivers: a latent class clustering approach

    DEFF Research Database (Denmark)

    Weiss, Harold B.; Kaplan, Sigal; Prato, Carlo Giacomo

    2016-01-01

    , infrastructure characteristics, environmental conditions, demographic characteristics, driving behaviour, and pre-crash manoeuvres. The analysis yielded 15 and 8 latent classes of, respectively, single-vehicle and multi-vehicle crashes, and average posterior probabilities measured the odds of correct...

  17. Sparse Solutions for Single Class SVMs: A Bi-Criterion Approach

    Data.gov (United States)

    National Aeronautics and Space Administration — In this paper we propose an innovative learning algorithm - a variation of One-class Support Vector Machines (SVMs) learning algorithm to produce sparser solutions...

  18. Recent developments of the quantum chemical cluster approach for modeling enzyme reactions.

    Science.gov (United States)

    Siegbahn, Per E M; Himo, Fahmi

    2009-06-01

    The quantum chemical cluster approach for modeling enzyme reactions is reviewed. Recent applications have used cluster models much larger than before which have given new modeling insights. One important and rather surprising feature is the fast convergence with cluster size of the energetics of the reactions. Even for reactions with significant charge separation it has in some cases been possible to obtain full convergence in the sense that dielectric cavity effects from outside the cluster do not contribute to any significant extent. Direct comparisons between quantum mechanics (QM)-only and QM/molecular mechanics (MM) calculations for quite large clusters in a case where the results differ significantly have shown that care has to be taken when using the QM/MM approach where there is strong charge polarization. Insights from the methods used, generally hybrid density functional methods, have also led to possibilities to give reasonable error limits for the results. Examples are finally given from the most extensive study using the cluster model, the one of oxygen formation at the oxygen-evolving complex in photosystem II.

  19. Examining Patterns of Exposure to Family Violence in Preschool Children: A Latent Class Approach.

    Science.gov (United States)

    Grasso, Damion J; Petitclerc, Amélie; Henry, David B; McCarthy, Kimberly J; Wakschlag, Lauren S; Briggs-Gowan, Margaret J

    2016-12-01

    Young children can experience violence directly or indirectly in the home, with some children exposed to multiple forms of violence. These polyvictims often experience violence that is severe, chronic, and multifaceted. The current study used latent class analysis to identify and examine the pattern of profiles of exposure to family violence (i.e., violence directed towards the child and between caregivers) among a sample of 474 children ages 3-6 year who were drawn from the Multidimensional Assessment of Preschoolers Study (Wakschlag et al., 2014). The data yielded 3 classes: a polyvictimized class (n = 72; 15.2%) with high probability of exposure to all forms of violence, a harsh parenting class (n = 235; 49.5%), distinguished mainly by child-directed physical discipline in the absence of more severe forms of violence, and a low-exposure class (n = 167; 35.2%). Classes were differentiated by contextual factors, maternal characteristics, and mother-reported and observational indicators of parenting and child functioning with most effect sizes between medium and large. These findings add to emerging evidence linking polyvictimization to impaired caregiving and adverse psychological outcomes for children and offer important insight for prevention and intervention for this vulnerable population. Copyright © 2016 International Society for Traumatic Stress Studies.

  20. A class Hierarchical, object-oriented approach to virtual memory management

    Science.gov (United States)

    Russo, Vincent F.; Campbell, Roy H.; Johnston, Gary M.

    1989-01-01

    The Choices family of operating systems exploits class hierarchies and object-oriented programming to facilitate the construction of customized operating systems for shared memory and networked multiprocessors. The software is being used in the Tapestry laboratory to study the performance of algorithms, mechanisms, and policies for parallel systems. Described here are the architectural design and class hierarchy of the Choices virtual memory management system. The software and hardware mechanisms and policies of a virtual memory system implement a memory hierarchy that exploits the trade-off between response times and storage capacities. In Choices, the notion of a memory hierarchy is captured by abstract classes. Concrete subclasses of those abstractions implement a virtual address space, segmentation, paging, physical memory management, secondary storage, and remote (that is, networked) storage. Captured in the notion of a memory hierarchy are classes that represent memory objects. These classes provide a storage mechanism that contains encapsulated data and have methods to read or write the memory object. Each of these classes provides specializations to represent the memory hierarchy.

  1. Behavioral and Mental Health Correlates of Youth Stalking Victimization: A Latent Class Approach.

    Science.gov (United States)

    Reidy, Dennis E; Smith-Darden, Joanne P; Kernsmith, Poco D

    2016-12-01

    Although recognized as a public health problem, little attention has been paid to the problem of stalking among youth. Latent profile analysis was used to identify latent groups of adolescent stalking victims and their behavioral and mental health correlates. A cross-sectional sample of 1,236 youths were randomly selected from 13 schools stratified by community risk level (i.e., low, moderate, and high risk) and gender. Students completed surveys assessing behavioral indicators of stalking victimization, as well as substance use, sexual behavior, dating violence, and psychiatric symptoms. Data were collected in 2013 and data analyses were performed in 2015. Analysis indicated the presence of a non-victim class, a minimal exposure class, and a victim class for boys and girls alike. Approximately 14% of girls and 13% of boys were in the stalking victim class. Adolescents in the victim class reported more symptoms of post-traumatic stress, mood disorder, and hopelessness, as well as more instances of alcohol use, binge drinking, and physical dating violence victimization. Girls in the victim class also reported engaging in sexting behaviors and oral sex with significantly more partners than their non-victim peers. These findings provide valuable knowledge of the prevalence and pertinent health correlates of stalking victimization in adolescence. The data suggest a substantial proportion of adolescents are victims of stalking and are likewise at risk for a number of deleterious health outcomes. As such, this population merits further attention by prevention researchers and practitioners. Published by Elsevier Inc.

  2. High Class-Imbalance in pre-miRNA Prediction: A Novel Approach Based on deepSOM.

    Science.gov (United States)

    Stegmayer, Georgina; Yones, Cristian; Kamenetzky, Laura; Milone, Diego H

    2017-01-01

    The computational prediction of novel microRNA within a full genome involves identifying sequences having the highest chance of being a miRNA precursor (pre-miRNA). These sequences are usually named candidates to miRNA. The well-known pre-miRNAs are usually only a few in comparison to the hundreds of thousands of potential candidates to miRNA that have to be analyzed, which makes this task a high class-imbalance classification problem. The classical way of approaching it has been training a binary classifier in a supervised manner, using well-known pre-miRNAs as positive class and artificially defining the negative class. However, although the selection of positive labeled examples is straightforward, it is very difficult to build a set of negative examples in order to obtain a good set of training samples for a supervised method. In this work, we propose a novel and effective way of approaching this problem using machine learning, without the definition of negative examples. The proposal is based on clustering unlabeled sequences of a genome together with well-known miRNA precursors for the organism under study, which allows for the quick identification of the best candidates to miRNA as those sequences clustered with known precursors. Furthermore, we propose a deep model to overcome the problem of having very few positive class labels. They are always maintained in the deep levels as positive class while less likely pre-miRNA sequences are filtered level after level. Our approach has been compared with other methods for pre-miRNAs prediction in several species, showing effective predictivity of novel miRNAs. Additionally, we will show that our approach has a lower training time and allows for a better graphical navegability and interpretation of the results. A web-demo interface to try deepSOM is available at http://fich.unl.edu.ar/sinc/web-demo/deepsom/.

  3. From a WebQuest to a ReadingQuest: learners' reactions in an EFL extensive reading class

    OpenAIRE

    Barros, Ana Cláudia; Amorim Carvalho, Ana Amélia

    2007-01-01

    Most students don’t like reading in a foreign language. They find it a difficult task, mainly due to the high number of unknown words they encounter when reading a text. They consider reading classes boring and uninteresting and as a result our students are poor readers. Concerned with this situation, we conducted a study on the impact of a learning environment based on the WebQuest, a ReadingQuest, and on student engagement in an extensive reading task. The results show that the ReadingQuest...

  4. Strategies for method development for an inductively coupled plasma mass spectrometer with bandpass reaction cell. Approaches with different reaction gases for the determination of selenium

    International Nuclear Information System (INIS)

    Hattendorf, Bodo; Guenther, Detlef

    2003-01-01

    An inductively coupled plasma mass spectrometer with dynamic reaction cell (DRC) was used to investigate different approaches for chemical resolution of Ar 2 + ions and to improve the determination of Se. Hydrogen, methane, oxygen and nitrous oxide were used as reaction gases. The method development for each approach consists of the acquisition of spectra for blank and spiked samples at different operating parameters, including reaction gas flow and transmission settings, of the DRC. Isotope ratio studies and the analytes signal to background ratio (SBR), were used as criteria to determine the operating conditions of the DRC where spectral interferences from the ion source or from polyatomic ions formed inside the DRC are minimized. Methane was found to provide the highest reaction efficiency for determination of Se. Nitrous oxide and oxygen also very efficiently suppress the Ar 2 + interference but reaction or scattering losses of Se + and SeO + are significant. Hydrogen is the least efficient gas for Ar 2 + reduction but little scattering or reactive loss lead to a good SBR. The determination of Se as SeO + was investigated with oxygen and nitrous oxide as reaction gases. The efficiency when using the oxygenation reaction was found to be similar to the efficiency for the charge transfer reactions but the slow oxygenation of the potentially interfering Mo + renders this approach less useful for analytical purposes. Using a natural water sample it could be shown that very good agreement is obtained using methane or hydrogen for analysis of 80 Se + at the μg/l level. Limits of detection are lowest (2 ng/l) when methane is used to suppress the Ar 2 + ion and when 80 Se + is used for analysis

  5. Development of a multiplex polymerase chain reaction protocol for the simultaneous detection of Salmonella enterica serovar Typhi and Class 1 integron

    Directory of Open Access Journals (Sweden)

    Juthika Mandal

    2014-09-01

    Full Text Available Objective: To develop a multiplex polymerase chain reaction (PCR protocol for the simultaneous detection of Salmonella enterica serovar Typhi (S. Typhi and Class 1 integron, so as to aid rapid diagnosis of S. Typhi cases and help in the selection of treatment options based on the presence of the Class 1 integron that can carry resistance cassettes to a range of antibiotics. Methods: PCR for amplification of specific regions was done using fliC-d and intl primers and agarose gel electrophoresis was used for resolution of PCR products. Results: The fliC-d primer (S. Typhi specific amplified a 587 bp region and the intl primer (Class 1 integron specific amplified two bands approximately 500 and 550 bps. The developed method was specific for S. Typhi and did not amplify any products with Salmonella enterica serovar Typhimurium ATCC 14028, Salmonella enterica serovar Paratyphi and Escherichia coli O157:H7. Conclusions: The developed multiplex PCR protocol can be used for rapid diagnosis and aid in proper treatment strategies for patients infected with S. Typhi.

  6. Using the latent class approach to cluster firms in benchmarking: An application to the US electricity transmission industry

    Directory of Open Access Journals (Sweden)

    Manuel Llorca

    2014-03-01

    Full Text Available In this paper we advocate using the latent class model (LCM approach to control for technological differences in traditional efficiency analysis of regulated electricity networks. Our proposal relies on the fact that latent class models are designed to cluster firms by uncovering differences in technology parameters. Moreover, it can be viewed as a supervised method for clustering data that takes into account the same (production or cost relationship that is analysed later, often using nonparametric frontier techniques. The simulation exercises show that the proposed approach outperforms other sample selection procedures. The proposed methodology is illustrated with an application to a sample of US electricity transmission firms for the period 2001–2009.

  7. Modeling Studies of Inhomogeneity Effects during Laser Flash Photolysis Experiments: A Reaction-Diffusion Approach.

    Science.gov (United States)

    Dóka, Éva; Lente, Gábor

    2017-04-13

    This work presents a rigorous mathematical study of the effect of unavoidable inhomogeneities in laser flash photolysis experiments. There are two different kinds of inhomegenities: the first arises from diffusion, whereas the second one has geometric origins (the shapes of the excitation and detection light beams). Both of these are taken into account in our reported model, which gives rise to a set of reaction-diffusion type partial differential equations. These equations are solved by a specially developed finite volume method. As an example, the aqueous reaction between the sulfate ion radical and iodide ion is used, for which sufficiently detailed experimental data are available from an earlier publication. The results showed that diffusion itself is in general too slow to influence the kinetic curves on the usual time scales of laser flash photolysis experiments. However, the use of the absorbances measured (e.g., to calculate the molar absorption coefficients of transient species) requires very detailed mathematical consideration and full knowledge of the geometrical shapes of the excitation laser beam and the separate detection light beam. It is also noted that the usual pseudo-first-order approach to evaluating the kinetic traces can be used successfully even if the usual large excess condition is not rigorously met in the reaction cell locally.

  8. Cyclist–motorist crash patterns in Denmark: A latent class clustering approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2013-01-01

    to prioritize safety issues and to devise efficient preventive measures. Method: The current study focused on cyclist–motorist crashes that occurred in Denmark during the period between 2007 and 2011. To uncover crash patterns, the current analysis applied latent class clustering, an unsupervised probabilistic...

  9. A disturbance attenuation approach for a class of continuous piecewise affine systems : control design and experiments

    NARCIS (Netherlands)

    Doris, A.; Wouw, van de N.; Heemels, W.P.M.H.; Nijmeijer, H.

    2010-01-01

    We consider the disturbance attenuation problem for a class of continuous piecewise affine systems. Hereto, observer-based output-feedback controllers are proposed that render the closed-loop system uniformly convergent. The convergence property ensures, first, stability and, second, the existence

  10. Designing Class Activities to Meet Specific Core Training Competencies: A Developmental Approach

    Science.gov (United States)

    Guth, Lorraine J.; McDonnell, Kelly A.

    2004-01-01

    This article presents a developmental model for designing and utilizing class activities to meet specific Association for Specialists in Group Work (ASGW) core training competencies for group workers. A review of the relevant literature about teaching group work and meeting core training standards is provided. The authors suggest a process by…

  11. Assessing Disease Class-Specific Diagnostic Ability: A Practical Adaptive Test Approach.

    Science.gov (United States)

    Papa, Frank J.; Schumacker, Randall E.

    Measures of the robustness of disease class-specific diagnostic concepts could play a central role in training programs designed to assure the development of diagnostic competence. In the pilot study, the authors used disease/sign-symptom conditional probability estimates, Monte Carlo procedures, and artificial intelligence (AI) tools to create…

  12. Effectively Serving the Needs of Today's Business Student: The Product Life Cycle Approach to Class Organization

    Science.gov (United States)

    Eastman, Jacqueline K.; Aviles, Maria; Hanna, Mark

    2012-01-01

    We illustrate a class organization process utilizing the concept of the Product Life Cycle to meet the needs of today's millennial student. In the Introduction stage of a business course, professors need to build structure to encourage commitment. In the Growth stage, professors need to promote the structure through multiple, brief activities that…

  13. Democracy: Its Meaning and Dissenting Opinions of the Political Class in Nigeria: A Philosophical Approach

    Science.gov (United States)

    Nwogu, G. A. I.

    2015-01-01

    The nascent democracy in Nigeria is plagued with myriad of intrigues, discordant opinions of the political class. The reason is not farfetched. Every political party sees its manifesto and plans of action as the best for the citizenry. They elbow each other in the process of garnering political recognition and vibrancy. Their unhealthy rivalry…

  14. Secondary School Students' Physical Activity Participation across Physical Education Classes: The Expectancy-Value Theory Approach

    Science.gov (United States)

    Gråstén, Arto; Watt, Anthony; Hagger, Martin; Jaakkola, Timo; Liukkonen, Jarmo

    2015-01-01

    The primary purpose of this study was to analyze the link between students' expectancy beliefs, subjective task values, out-of-school activity, and moderate to vigorous physical activity (MVPA) participation across secondary school physical education (PE) classes. The sample comprised 96 students (58 girls, 38 boys; Mage = 15.03, SD = 0.94) from…

  15. Cross-Informant Agreement on Child and Adolescent Withdrawn Behavior: A Latent Class Approach

    Science.gov (United States)

    Rubin, David H.; Althoff, Robert R.; Walkup, John T.; Hudziak, James J.

    2013-01-01

    Withdrawn behavior (WB) relates to many developmental outcomes, including pervasive developmental disorders, anxiety, depression, psychosis, personality disorders and suicide. No study has compared the latent profiles of different informants' reports on WB. This study uses multi-informant latent class analyses (LCA) of the child behavior checklist…

  16. Case Studies of Interactive Whole-Class Teaching in Primary Science: Communicative Approach and Pedagogic Purposes

    Science.gov (United States)

    McMahon, Kendra

    2012-01-01

    By developing two case studies of expert teaching in action, this study aimed to develop knowledge of talk in whole-class teaching in UK primary science lessons and understand this in relation to both the teachers' interpretations and sociocultural theoretical frameworks. Lessons were observed and video-recorded and the teachers engaged in…

  17. Practitioners' Perceptions of Dyslexia and Approaches towards Teaching Learners with Dyslexia in Adult Literacy Classes

    Science.gov (United States)

    Ade-Ojo, Gordon O.

    2012-01-01

    Learners with dyslexia are likely to be over-represented in adult literacy classes because of the convergence in perceptions, causes and understanding of literacy problems and dyslexia. Given the great amount of apprehension about practitioners' and policy makers' understanding of dyslexia itself, it is important to carry out an exploration of the…

  18. Understanding Protein Synthesis: A Role-Play Approach in Large Undergraduate Human Anatomy and Physiology Classes

    Science.gov (United States)

    Sturges, Diana; Maurer, Trent W.; Cole, Oladipo

    2009-01-01

    This study investigated the effectiveness of role play in a large undergraduate science class. The targeted population consisted of 298 students enrolled in 2 sections of an undergraduate Human Anatomy and Physiology course taught by the same instructor. The section engaged in the role-play activity served as the study group, whereas the section…

  19. ADOPTING THE PROBLEM BASED LEARNING APPROACH IN A GIS PROJECT MANAGEMENT CLASS

    Science.gov (United States)

    Problem Based Learning (PBL) is a process that emphasizes the need for developing problem solving skills through hands-on project formulation and management. A class adopting the PBL method provides students with an environment to acquire necessary knowledge to encounter, unders...

  20. A Neurocomputational Approach to Trained and Transitive Relations in Equivalence Classes

    Directory of Open Access Journals (Sweden)

    Ángel E. Tovar

    2017-10-01

    Full Text Available A stimulus class can be composed of perceptually different but functionally equivalent stimuli. The relations between the stimuli that are grouped in a class can be learned or derived from other stimulus relations. If stimulus A is equivalent to B, and B is equivalent to C, then the equivalence between A and C can be derived without explicit training. In this work we propose, with a neurocomputational model, a basic learning mechanism for the formation of equivalence. We also describe how the relatedness between the members of an equivalence class is developed for both trained and derived stimulus relations. Three classic studies on stimulus equivalence are simulated covering typical and atypical populations as well as nodal distance effects. This model shows a mechanism by which certain stimulus associations are selectively strengthened even when they are not co-presented in the environment. This model links the field of equivalence classes to accounts of Hebbian learning and categorization, and points to the pertinence of modeling stimulus equivalence to explore the effect of variations in training protocols.

  1. Technological and Traditional Drawing Approaches Encourage Active Engagement in Histology Classes for Science Undergraduates

    Science.gov (United States)

    Cogdell, Barbara; Torsney, Ben; Stewart, Katherine; Smith, Robert A.

    2012-01-01

    In order to promote more active engagement of science undergraduates in histology practical classes some technology-based innovations were introduced. First, an interactive pre-lab tutorial was set up using an electronic handset voting system, where guidance on tissue analysis was given. Second, a web-based resource where students could access…

  2. Beyond mean-field approach to heavy-ion reactions around the Coulomb barrier

    Directory of Open Access Journals (Sweden)

    Ayik Sakir

    2011-10-01

    Full Text Available Dissipation and fluctuations of one-body observables in heavy-ion reactions around the Coulomb barrier are investigated with a microscopic stochastic mean-field approach. By projecting the stochastic meanfield dynamics on a suitable collective path, transport coefficients associated with the relative distance between colliding nuclei and a fragment mass are extracted. Although microscopic mean-field approach is know to underestimate the variance of fragment mass distribution, the description of the variance is much improved by the stochastic mean-field method. While fluctuations are consistent with the empirical (semiclassical analysis of the experimental data, concerning mean values of macroscopic variables the semiclassical description breaks down below the Coulomb barrier.

  3. Maximal Predictability Approach for Identifying the Right Descriptors for Electrocatalytic Reactions.

    Science.gov (United States)

    Krishnamurthy, Dilip; Sumaria, Vaidish; Viswanathan, Venkatasubramanian

    2018-02-01

    Density functional theory (DFT) calculations are being routinely used to identify new material candidates that approach activity near fundamental limits imposed by thermodynamics or scaling relations. DFT calculations are associated with inherent uncertainty, which limits the ability to delineate materials (distinguishability) that possess high activity. Development of error-estimation capabilities in DFT has enabled uncertainty propagation through activity-prediction models. In this work, we demonstrate an approach to propagating uncertainty through thermodynamic activity models leading to a probability distribution of the computed activity and thereby its expectation value. A new metric, prediction efficiency, is defined, which provides a quantitative measure of the ability to distinguish activity of materials and can be used to identify the optimal descriptor(s) ΔG opt . We demonstrate the framework for four important electrochemical reactions: hydrogen evolution, chlorine evolution, oxygen reduction and oxygen evolution. Future studies could utilize expected activity and prediction efficiency to significantly improve the prediction accuracy of highly active material candidates.

  4. Mechanisms before Reactions: A Mechanistic Approach to the Organic Chemistry Curriculum Based on Patterns of Electron Flow

    Science.gov (United States)

    Flynn, Alison B.; Ogilvie, William W.

    2015-01-01

    A significant redesign of the introductory organic chemistry curriculum at the authors' institution is described. There are two aspects that differ greatly from a typical functional group approach. First, organic reaction mechanisms and the electron-pushing formalism are taught before students have learned a single reaction. The conservation of…

  5. Qualitative Variation in Approaches to University Teaching and Learning in Large First-Year Classes

    Science.gov (United States)

    Prosser, Michael; Trigwell, Keith

    2014-01-01

    Research on teaching from a student learning perspective has identified two qualitatively different approaches to university teaching. They are an information transmission and teacher-focused approach, and a conceptual change and student-focused approach. The fundamental difference being in the former the intention is to transfer information to…

  6. A Behavioral Approach to Understanding Green Consumerism Using Latent Class Choice Analysis

    DEFF Research Database (Denmark)

    Peschel, Anne Odile; Grebitus, Carola; Steiner, Bodo

    on individuals' environmental attitudes and values. Consumer involvement and environmental attitudes contribute significantly toward explaining sustainable choices, suggesting that greater consumer involvement may be targeted by policy makers and firms to more effectively nudge consumers toward green consumerism......To better understand motivations of consumers making choices among sustainability-labeled food products, this paper analyzes drivers of stated choices for a dietary staple labeled with carbon and water foodprints. Latent class modeling of survey responses reveals distinct consumer segments based...

  7. Prediction of protein structural classes by Chou's pseudo amino acid composition: approached using continuous wavelet transform and principal component analysis.

    Science.gov (United States)

    Li, Zhan-Chao; Zhou, Xi-Bin; Dai, Zong; Zou, Xiao-Yong

    2009-07-01

    A prior knowledge of protein structural classes can provide useful information about its overall structure, so it is very important for quick and accurate determination of protein structural class with computation method in protein science. One of the key for computation method is accurate protein sample representation. Here, based on the concept of Chou's pseudo-amino acid composition (AAC, Chou, Proteins: structure, function, and genetics, 43:246-255, 2001), a novel method of feature extraction that combined continuous wavelet transform (CWT) with principal component analysis (PCA) was introduced for the prediction of protein structural classes. Firstly, the digital signal was obtained by mapping each amino acid according to various physicochemical properties. Secondly, CWT was utilized to extract new feature vector based on wavelet power spectrum (WPS), which contains more abundant information of sequence order in frequency domain and time domain, and PCA was then used to reorganize the feature vector to decrease information redundancy and computational complexity. Finally, a pseudo-amino acid composition feature vector was further formed to represent primary sequence by coupling AAC vector with a set of new feature vector of WPS in an orthogonal space by PCA. As a showcase, the rigorous jackknife cross-validation test was performed on the working datasets. The results indicated that prediction quality has been improved, and the current approach of protein representation may serve as a useful complementary vehicle in classifying other attributes of proteins, such as enzyme family class, subcellular localization, membrane protein types and protein secondary structure, etc.

  8. Bacterial discrimination by means of a universal array approach mediated by LDR (ligase detection reaction

    Directory of Open Access Journals (Sweden)

    Consolandi Clarissa

    2002-09-01

    Full Text Available Abstract Background PCR amplification of bacterial 16S rRNA genes provides the most comprehensive and flexible means of sampling bacterial communities. Sequence analysis of these cloned fragments can provide a qualitative and quantitative insight of the microbial population under scrutiny although this approach is not suited to large-scale screenings. Other methods, such as denaturing gradient gel electrophoresis, heteroduplex or terminal restriction fragment analysis are rapid and therefore amenable to field-scale experiments. A very recent addition to these analytical tools is represented by microarray technology. Results Here we present our results using a Universal DNA Microarray approach as an analytical tool for bacterial discrimination. The proposed procedure is based on the properties of the DNA ligation reaction and requires the design of two probes specific for each target sequence. One oligo carries a fluorescent label and the other a unique sequence (cZipCode or complementary ZipCode which identifies a ligation product. Ligated fragments, obtained in presence of a proper template (a PCR amplified fragment of the 16s rRNA gene contain either the fluorescent label or the unique sequence and therefore are addressed to the location on the microarray where the ZipCode sequence has been spotted. Such an array is therefore "Universal" being unrelated to a specific molecular analysis. Here we present the design of probes specific for some groups of bacteria and their application to bacterial diagnostics. Conclusions The combined use of selective probes, ligation reaction and the Universal Array approach yielded an analytical procedure with a good power of discrimination among bacteria.

  9. Reaction to and Coping With Domestic Violence by Iranian Women Victims: A Qualitative Approach.

    Science.gov (United States)

    Bahrami, Masoud; Shokrollahi, Paymaneh; Kohan, Shahnaz; Momeni, Ghodratollah; Rivaz, Mozhgan

    2015-11-18

    Domestic violence is a continual stressor that motivates its victim to react. The way a woman deals with her husband's violence determine the consequence of the violent relationship. In the present study, a qualitative approach was employed to investigate women's reactions to and ways of coping with domestic violence. Semi-structured interviews were conducted in 2014 with 18 women who experienced domestic violence in an attempt to explain how women deal with domestic violence. After the interviews were transcribed word by word, they were explored in the form of meaningful units and encoded as subcategories and categories through inductive content analysis. The reliability and validity of the interviews were measured by an external supervisor. Two categories of reaction and coping were identified through content analysis: passive and non-normative measures and active measures. Passive and non-normative measures included the subcategories of harmful behaviors, retaliation, tolerance, and silence. Active measures included seeking help and advice, legal measures, leaving the spouse, positive and health promoting measures. In the present study, ways of coping with a husband's violence among women experiencing domestic violence were divided into two categories: passive and non-normative measures and active measures. These categories confirmed the models of coping with stress in previous studies. Adopting an appropriate approach to dealing with domestic violence is affected by a woman's capacity and beliefs, the dominant culture, intensity of the violence, available social and legal supports, and effectiveness of evaluation measures. To generalize service provision to victimized women, the type of coping and the reason for adopting the chosen approach need to be taken into account.

  10. A Literary Approach to teaching English Language in a Multi – Cultural Class - Room

    Directory of Open Access Journals (Sweden)

    Sanju Choudhary

    2016-12-01

    Full Text Available Literature is not generally considered as a coherent branch of the curriculum in relation to language – development in either mother tongue or foreign language – teaching. As teachers of English in Multi cultural Indian class rooms we come across students with varying degree of competence in English language learning. Though, language learning is a natural process for natives but the Students of other languages put in colossal efforts to learn it. Despite   their sincere efforts they face challenges regarding Pronunciation, Spelling and Vocabulary. The Indian class rooms are a microcosm of the larger society, so teaching English language in a manner which equips the students to face the cut-throat competition has become a necessity and a challenge for English language Teachers. English today has become the key determinant for getting success in their career. The hackneyed and stereotypical methods of teaching are not acceptable now. Teachers have no longer remained arbitrary dispensers of knowledge but they are playing the role of a guide and facilitator for the students. Teachers of English are using innovative ideas to make English language teaching and learning interesting and simple. Teachers have started using the literary texts and their analysis to explore and ignite the imagination and creative skills of the students. One needs to think and rethink the contribution of literature to intelligent thinking as well as its role in the process of teaching – learning. My paper would, therefore, be an attempt at exploring the nature of the literary experience in the present day class rooms; and the broader role of literature in life.

  11. A variational approach to moment-closure approximations for the kinetics of biomolecular reaction networks

    Science.gov (United States)

    Bronstein, Leo; Koeppl, Heinz

    2018-01-01

    Approximate solutions of the chemical master equation and the chemical Fokker-Planck equation are an important tool in the analysis of biomolecular reaction networks. Previous studies have highlighted a number of problems with the moment-closure approach used to obtain such approximations, calling it an ad hoc method. In this article, we give a new variational derivation of moment-closure equations which provides us with an intuitive understanding of their properties and failure modes and allows us to correct some of these problems. We use mixtures of product-Poisson distributions to obtain a flexible parametric family which solves the commonly observed problem of divergences at low system sizes. We also extend the recently introduced entropic matching approach to arbitrary ansatz distributions and Markov processes, demonstrating that it is a special case of variational moment closure. This provides us with a particularly principled approximation method. Finally, we extend the above approaches to cover the approximation of multi-time joint distributions, resulting in a viable alternative to process-level approximations which are often intractable.

  12. The effectiveness of TBL with real patients in neurology education in terms of knowledge retention, in-class engagement, and learner reactions.

    Science.gov (United States)

    Alimoglu, Mustafa Kemal; Yardım, Selda; Uysal, Hilmi

    2017-03-01

    In our medical school, we changed from a lecture-based method to a team-based learning (TBL) method to teach "polyneuropathies" in the neurology clerkship starting from the 2014 to 2015 academic year. Real patients were used instead of written scenarios in TBL sessions. This study aimed to compare former lecture-based and the current TBL methods in terms of knowledge retention, in-class learner engagement, and learner reactions. First, we determined in-class engagement and satisfaction of the students for the lectures given in the 2013-2014 academic year. The following year, besides the same criteria, we also determined individual (IRAT) and group readiness test (GRAT) scores in the TBL group. End-of-clerkship exam scores for both groups were recorded. Additionally, opinions of patients about their experiences throughout the TBL process were determined. One year later (2015 for lecture and 2016 for TBL), both groups sat for an MCQ test to determine their knowledge retention levels. We found no difference between groups regarding end-of-clerkship exam scores. The mean knowledge retention test score of the TBL group was significantly higher than that of the lecture group (5.85 ± 1.74 vs. 3.28 ± 1.70). The differences between IRAT, GRAT, and retention test scores in the TBL group were significant. The mean student satisfaction score on a five-point scale was 3.01 ± 0.9 (median = 3) in the lecture group and 4.11 ± 1.1 (median = 4) in the TBL group. Our results seem encouraging for use of TBL performed with real patients in neurology education to achieve better long-term knowledge retention and higher in-class engagement and student satisfaction. Copyright © 2017 the American Physiological Society.

  13. Variations in adolescents’ motivational characteristics across gender and physical activity patterns: A latent class analysis approach

    Directory of Open Access Journals (Sweden)

    Margaret Lawler

    2017-08-01

    Full Text Available Abstract Background Neglecting to take account of the underlying context or type of physical activity (PA that underpins overall involvement has resulted in a limited understanding of adolescents’ PA participation. The purpose of the present research was to identify male and female adolescents’ leisure time PA patterns and examine whether psychological processes derived from self-determination theory differ as a function of the pattern of PA undertaken. Methods Nine hundred ninety-five students (61.2% females, 38.8% males; M age = 13.72 years, SD = 1.25 from eight secondary schools in Dublin, Ireland completed a physical activity recall 7 day diary and measures of intrinsic motivation, competence, relatedness, autonomy and autonomy support. Based on the diary five binary indicators of physical activity were derived reflecting recommended levels of MVPA on a minimum of 3 days, at least three sessions of non-organized physical activity (e.g. jog, team sport, individual sport, and organized non-sport physical activity (e.g. dance. Latent class analysis was used to identify subgroups of adolescents that engaged in similar patterns of physical activity. Profiles of physical activity participation were subsequently compared on motivational characteristics using Kruskal-Wallis tests. Results Latent class analysis revealed six distinct classes for girls (Organized Run/Swim & Dance/Gym; Organized Dance; Leisure Active Team Sport; Active Individual Sport; Walk/Run/Outdoor games; Non-Participation and five for boys (Leisure Active Gym; Leisure Active Individual Sport; Active Team Sport; Active Mixed Type; Non-Participation. Significant differences were found between the classes. Girls characterized by participation in team or individual sport, and boys represented by team sport participation demonstrated significantly higher self-determined motivational characteristics relative to other profiles of physical activity. Conclusion This research

  14. Variations in adolescents' motivational characteristics across gender and physical activity patterns: A latent class analysis approach.

    Science.gov (United States)

    Lawler, Margaret; Heary, Caroline; Nixon, Elizabeth

    2017-08-17

    Neglecting to take account of the underlying context or type of physical activity (PA) that underpins overall involvement has resulted in a limited understanding of adolescents' PA participation. The purpose of the present research was to identify male and female adolescents' leisure time PA patterns and examine whether psychological processes derived from self-determination theory differ as a function of the pattern of PA undertaken. Nine hundred ninety-five students (61.2% females, 38.8% males; M age = 13.72 years, SD = 1.25) from eight secondary schools in Dublin, Ireland completed a physical activity recall 7 day diary and measures of intrinsic motivation, competence, relatedness, autonomy and autonomy support. Based on the diary five binary indicators of physical activity were derived reflecting recommended levels of MVPA on a minimum of 3 days, at least three sessions of non-organized physical activity (e.g. jog), team sport, individual sport, and organized non-sport physical activity (e.g. dance). Latent class analysis was used to identify subgroups of adolescents that engaged in similar patterns of physical activity. Profiles of physical activity participation were subsequently compared on motivational characteristics using Kruskal-Wallis tests. Latent class analysis revealed six distinct classes for girls (Organized Run/Swim & Dance/Gym; Organized Dance; Leisure Active Team Sport; Active Individual Sport; Walk/Run/Outdoor games; Non-Participation) and five for boys (Leisure Active Gym; Leisure Active Individual Sport; Active Team Sport; Active Mixed Type; Non-Participation). Significant differences were found between the classes. Girls characterized by participation in team or individual sport, and boys represented by team sport participation demonstrated significantly higher self-determined motivational characteristics relative to other profiles of physical activity. This research offers a nuanced insight into the underlying type of activities that

  15. Knowledge Bases, Talents and Contexts: On the Usefulness of the Creative Class Approach in Sweden

    DEFF Research Database (Denmark)

    Asheim, Bjørn T.; Hansen, Høgni Kalsø

    2009-01-01

    The geography of the creative class and its impact on regional development has been debated for some years. While the ideas of Richard Florida have permeated local and regional planning strategies in most parts of the Western world, critiques have been numerous. Florida’s 3T’s (technology, talent....... Furthermore, the dominating knowledge base in a region has an influence on the importance of a people climate and a business climate for attracting and retaining talent. In this article, we present an empirical analysis in support of these arguments using original Swedish data....

  16. An Integrated Approach to Preempt Cheating on Asynchronous, Objective, Online Assessments in Graduate Business Classes

    Science.gov (United States)

    Sullivan, Daniel P.

    2016-01-01

    Cheating, left untended, erodes the validity of evaluation and, ultimately, corrupts the legitimacy of a course. We profile an approach to manage, with an eye toward preempting, cheating on asynchronous, objective, online quizzes. This approach taps various technological and social solutions to academic dishonesty, integrating them into a…

  17. Peer-led, transformative learning approaches increase classroom engagement in care self-management classes during inpatient rehabilitation of individuals with spinal cord injury.

    Science.gov (United States)

    Gassaway, Julie; Jones, Michael L; Sweatman, W Mark; Young, Tamara

    2017-10-16

    Evaluate effects of revised education classes on classroom engagement during inpatient rehabilitation for individuals with spinal cord injury/disease (SCI/D). Multiple-baseline, quasi-experimental design with video recorded engagement observations during conventional and revised education classes; visual and statistical analysis of difference in positive engagement responses observed in classes using each approach. 81 patients (72% male, 73% white, mean age 36 SD 15.6) admitted for SCI/D inpatient rehabilitation in a non-profit rehabilitation hospital, who attended one or more of 33 care self-management education classes that were video recorded. All study activities were approved by the host facility institutional review board. Conventional nurse-led self-management classes were replaced with revised peer-led classes incorporating approaches to promote transformative learning. Revised classes were introduced across three subject areas in a step-wise fashion over 15 weeks. Positive engagement responses (asking questions, participating in discussion, gesturing, raising hand, or otherwise noting approval) were documented from video recordings of 14 conventional and 19 revised education classes. Significantly higher average (per patient per class) positive engagement responses were observed in the revised compared to conventional classes (p=0.008). Redesigning SCI inpatient rehabilitation care self-management classes to promote transformative learning increased patient engagement. Additional research is needed to examine longer term outcomes and replicability in other settings.

  18. Nitrogen-doped graphene prepared by a transfer doping approach for the oxygen reduction reaction application

    Science.gov (United States)

    Mo, Zaiyong; Zheng, Ruiping; Peng, Hongliang; Liang, Huagen; Liao, Shijun

    2014-01-01

    Well defined nitrogen-doped graphene (NG) is prepared by a transfer doping approach, in which the graphene oxide (GO) is deoxidized and nitrogen doped by the vaporized polyaniline, and the GO is prepared by a thermal expansion method from graphite oxide. The content of doped nitrogen in the doped graphene is high up to 6.25 at% by the results of elements analysis, and oxygen content is lowered to 5.17 at%. As a non-precious metal cathode electrocatalyst, the NG catalyst exhibits excellent activity toward the oxygen reduction reaction, as well as excellent tolerance toward methanol. In 0.1 M KOH solution, its onset potential, half-wave potential and limiting current density for the oxygen reduction reaction reach 0.98 V (vs. RHE), 0.87 V (vs. RHE) and 5.38 mA cm-2, respectively, which are comparable to those of commercial 20 wt% Pt/C catalyst. The well defined graphene structure of the catalyst is revealed clearly by HRTEM and Raman spectra. It is suggested that the nitrogen-doping and large surface area of the NG sheets give the main contribution to the high ORR catalytic activity.

  19. A multi target approach to control chemical reactions in their inhomogeneous solvent environment

    International Nuclear Information System (INIS)

    Keefer, Daniel; Thallmair, Sebastian; Zauleck, Julius P P; Vivie-Riedle, Regina de

    2015-01-01

    Shaped laser pulses offer a powerful tool to manipulate molecular quantum systems. Their application to chemical reactions in solution is a promising concept to redesign chemical synthesis. Along this road, theoretical developments to include the solvent surrounding are necessary. An appropriate theoretical treatment is helpful to understand the underlying mechanisms. In our approach we simulate the solvent by randomly selected snapshots from molecular dynamics trajectories. We use multi target optimal control theory to optimize pulses for the various arrangements of explicit solvent molecules simultaneously. This constitutes a major challenge for the control algorithm, as the solvent configurations introduce a large inhomogeneity to the potential surfaces. We investigate how the algorithm handles the new challenges and how well the controllability of the system is preserved with increasing complexity. Additionally, we introduce a way to statistically estimate the efficiency of the optimized laser pulses in the complete thermodynamical ensemble. (paper)

  20. Molecule-Level g-C3N4 Coordinated Transition Metals as a New Class of Electrocatalysts for Oxygen Electrode Reactions

    KAUST Repository

    Zheng, Yao

    2017-02-21

    Organometallic complexes with metal-nitrogen/carbon (M-N/C) coordination are the most important alternatives to precious metal catalysts for oxygen reduction and evolution reactions (ORR and OER) in energy conversion devices. Here, we designed and developed a range of molecule-level graphitic carbon nitride (g-C3N4) coordinated transition metals (M-C3N4) as a new generation of M-N/C catalysts for these oxygen electrode reactions. As a proof-of-concept example, we conducted theoretical evaluation and experimental validation on a cobalt-C3N4 catalyst with a desired molecular configuration, which possesses comparable electrocatalytic activity to that of precious metal benchmarks for the ORR and OER in alkaline media. The correlation of experimental and computational results confirms that this high activity originates from the precise M-N2 coordination in the g-C3N4 matrix. Moreover, the reversible ORR/OER activity trend for a wide variety of M-C3N4 complexes has been constructed to provide guidance for the molecular design of this promising class of catalysts.

  1. Family, state, class and solidarity: re-conceptualising intergenerational solidarity through the grounded theory approach.

    Science.gov (United States)

    Timonen, Virpi; Conlon, Catherine; Scharf, Thomas; Carney, Gemma

    2013-09-01

    The relationship between class and intergenerational solidarities in the public and private spheres calls for further conceptual and theoretical development. This article discusses the findings from the first wave of a qualitative longitudinal study entitled Changing Generations , conducted in Ireland in 2011-2012, comprising 100 in-depth interviews with men and women across the age and socioeconomic spectrums. Constructivist grounded theory analysis of the data gives rise to the following postulates: (1) intergenerational solidarity at the family level is strongly contoured by socioeconomic status (SES); (2) intergenerational solidarity evolves as family generations observe each others' practices and adjust their expectations accordingly; (3) intergenerational solidarity within families is also shaped by the public sphere (the welfare state) that generates varying expectations and levels of solidarity regarding State supports for different age groups, again largely dependent on SES; (4) the liberal welfare state context, especially at a time of economic crisis, enhances the significance of intergenerational solidarity within families. We conclude by calling for research that is attuned to age/generation, gender and class, and how these operate across the family and societal levels.

  2. Margins of freedom: a field-theoretic approach to class-based health dispositions and practices.

    Science.gov (United States)

    Burnett, Patrick John; Veenstra, Gerry

    2017-09-01

    Pierre Bourdieu's theory of practice situates social practices in the relational interplay between experiential mental phenomena (habitus), resources (capitals) and objective social structures (fields). When applied to class-based practices in particular, the overarching field of power within which social classes are potentially made manifest is the primary field of interest. Applying relational statistical techniques to original survey data from Toronto and Vancouver, Canada, we investigated whether smoking, engaging in physical activity and consuming fruit and vegetables are dispersed in a three-dimensional field of power shaped by economic and cultural capitals and cultural dispositions and practices. We find that aesthetic dispositions and flexibility of developing and established dispositions are associated with positioning in the Canadian field of power and embedded in the logics of the health practices dispersed in the field. From this field-theoretic perspective, behavioural change requires the disruption of existing relations of harmony between the habitus of agents, the fields within which the practices are enacted and the capitals that inform and enforce the mores and regularities of the fields. The three-dimensional model can be explored at: http://relational-health.ca/margins-freedom. © 2017 Foundation for the Sociology of Health & Illness.

  3. diceR: an R package for class discovery using an ensemble driven approach.

    Science.gov (United States)

    Chiu, Derek S; Talhouk, Aline

    2018-01-15

    Given a set of features, researchers are often interested in partitioning objects into homogeneous clusters. In health research, cancer research in particular, high-throughput data is collected with the aim of segmenting patients into sub-populations to aid in disease diagnosis, prognosis or response to therapy. Cluster analysis, a class of unsupervised learning techniques, is often used for class discovery. Cluster analysis suffers from some limitations, including the need to select up-front the algorithm to be used as well as the number of clusters to generate, in addition, there may exist several groupings consistent with the data, making it very difficult to validate a final solution. Ensemble clustering is a technique used to mitigate these limitations and facilitate the generalization and reproducibility of findings in new cohorts of patients. We introduce diceR (diverse cluster ensemble in R), a software package available on CRAN: https://CRAN.R-project.org/package=diceR CONCLUSIONS: diceR is designed to provide a set of tools to guide researchers through a general cluster analysis process that relies on minimizing subjective decision-making. Although developed in a biological context, the tools in diceR are data-agnostic and thus can be applied in different contexts.

  4. New approach to analyzing and evaluating cross sections for partial photoneutron reactions

    International Nuclear Information System (INIS)

    Varlamov, V. V.; Ishkhanov, B. S.; Orlin, V. N.

    2012-01-01

    The presence of substantial systematic discrepancies between the results of different experiments devoted to determining cross sections for partial photoneutron reactions—first of all, (γ, n), (γ, 2n), and (γ, 3n) reactions—is a strong motivation for studying the reliability and authenticity of these data and for developing methods for taking into account and removing the discrepancies in question. In order to solve the first problem, we introduce objective absolute criteria involving transitional photoneutron-multiplicity functions F 1 , F 2 , F 3 , …; by definition, their values cannot exceed 1.0, 0.5, 0.33, …, respectively. With the aim of solving the second problem, we propose a new experimental-theoretical approach. In this approach, reaction cross sections are evaluated by simultaneously employing experimental data on the cross section for the total photoneutron yield, σ expt (γ, xn) = σ expt (γ, n) + 2σ expt (γ, 2n) + 3σ expt (γ, 3n) + …, which are free from drawbacks plaguing experimental methods for sorting neutrons in multiplicity, and the results obtained by calculating the functions F theor 1 , F theor 2 , F theor 3 , … on the basis of the modern model of photonuclear reactions. The reliability and authenticity of data on the cross sections for (γ, n), (γ, 2n), and (γ, 3n) partial reactions—σ eval (γ, in) = F i theor σ expt (γ, xn)—were evaluated for the 90 Zr, 115 In, 112,114,116,117,118,119,120,122,124 Sn, 159 Tb, and 197 Au nuclei.

  5. Assessing Adolescents' Understanding of and Reactions to Stress in Different Cultures: Results of a Mixed-Methods Approach

    Science.gov (United States)

    Nastasi, Bonnie K.; Hitchcock, John H.; Burkholder, Gary; Varjas, Kristen; Sarkar, Sreeroopa; Jayasena, Asoka

    2007-01-01

    This article expands on an emerging mixed-method approach for validating culturally-specific constructs (see Hitchcock et al., 2005). Previous work established an approach for dealing with cultural impacts when assessing psychological constructs and the current article extends these efforts into studying stress reactions among adolescents in Sri…

  6. Chemical reaction rates and non-equilibrium pressure of reacting gas mixtures in the state-to-state approach

    International Nuclear Information System (INIS)

    Kustova, Elena V.; Kremer, Gilberto M.

    2014-01-01

    Highlights: • State-to-state approach for coupled vibrational relaxation and chemical reactions. • Self-consistent model for rates of non-equilibrium reactions and energy transitions. • In viscous flows mass action law is violated. • Cross coupling between reaction rates and non-equilibrium pressure in viscous flow. • Results allow implementing the state-to-state approach for viscous flow simulations. - Abstract: Viscous gas flows with vibrational relaxation and chemical reactions in the state-to-state approach are analyzed. A modified Chapman–Enskog method is used for the determination of chemical reaction and vibrational transition rates and non-equilibrium pressure. Constitutive equations depend on the thermodynamic forces: velocity divergence and chemical reaction/transition affinity. As an application, N 2 flow with vibrational relaxation across a shock wave is investigated. Two distinct processes occur behind the shock: for small values of the distance the affinity is large and vibrational relaxation is in its initial stage; for large distances the affinity is small and the chemical reaction is in its final stage. The affinity contributes more to the transition rate than the velocity divergence and the effect of these two contributions are more important for small distances from the shock front. For the non-equilibrium pressure, the term associated with the bulk viscosity increases by a small amount the hydrostatic pressure

  7. Chemical reaction rates and non-equilibrium pressure of reacting gas mixtures in the state-to-state approach

    Energy Technology Data Exchange (ETDEWEB)

    Kustova, Elena V., E-mail: e.kustova@spbu.ru [Department of Mathematics and Mechanics, Saint Petersburg State University, 198504 Universitetskiy pr. 28, Saint Petersburg (Russian Federation); Kremer, Gilberto M., E-mail: kremer@fisica.ufpr.br [Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, 81531-980 Curitiba (Brazil)

    2014-12-05

    Highlights: • State-to-state approach for coupled vibrational relaxation and chemical reactions. • Self-consistent model for rates of non-equilibrium reactions and energy transitions. • In viscous flows mass action law is violated. • Cross coupling between reaction rates and non-equilibrium pressure in viscous flow. • Results allow implementing the state-to-state approach for viscous flow simulations. - Abstract: Viscous gas flows with vibrational relaxation and chemical reactions in the state-to-state approach are analyzed. A modified Chapman–Enskog method is used for the determination of chemical reaction and vibrational transition rates and non-equilibrium pressure. Constitutive equations depend on the thermodynamic forces: velocity divergence and chemical reaction/transition affinity. As an application, N{sub 2} flow with vibrational relaxation across a shock wave is investigated. Two distinct processes occur behind the shock: for small values of the distance the affinity is large and vibrational relaxation is in its initial stage; for large distances the affinity is small and the chemical reaction is in its final stage. The affinity contributes more to the transition rate than the velocity divergence and the effect of these two contributions are more important for small distances from the shock front. For the non-equilibrium pressure, the term associated with the bulk viscosity increases by a small amount the hydrostatic pressure.

  8. Measuring energy efficiency under heterogeneous technologies using a latent class stochastic frontier approach: An application to Chinese energy economy

    International Nuclear Information System (INIS)

    Lin, Boqiang; Du, Kerui

    2014-01-01

    The importance of technology heterogeneity in estimating economy-wide energy efficiency has been emphasized by recent literature. Some studies use the metafrontier analysis approach to estimate energy efficiency. However, for such studies, some reliable priori information is needed to divide the sample observations properly, which causes a difficulty in unbiased estimation of energy efficiency. Moreover, separately estimating group-specific frontiers might lose some common information across different groups. In order to overcome these weaknesses, this paper introduces a latent class stochastic frontier approach to measure energy efficiency under heterogeneous technologies. An application of the proposed model to Chinese energy economy is presented. Results show that the overall energy efficiency of China's provinces is not high, with an average score of 0.632 during the period from 1997 to 2010. - Highlights: • We introduce a latent class stochastic frontier approach to measure energy efficiency. • Ignoring technological heterogeneity would cause biased estimates of energy efficiency. • An application of the proposed model to Chinese energy economy is presented. • There is still a long way for China to develop an energy efficient regime

  9. Supervised pre-processing approaches in multiple class variables classification for fish recruitment forecasting

    KAUST Repository

    Fernandes, José Antonio; Lozano, Jose A.; Iñ za, Iñ aki; Irigoien, Xabier; Pé rez, Aritz; Rodrí guez, Juan Diego

    2013-01-01

    A multi-species approach to fisheries management requires taking into account the interactions between species in order to improve recruitment forecasting of the fish species. Recent advances in Bayesian networks direct the learning of models

  10. General approach to standardization of the solid-phase radioimmunoassay for quantitation of class-specific antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Zollinger, W D; Boslego, J W [Walter Reed Army Inst. of Research, Washington, DC (USA)

    1981-10-30

    The feasibility of using an anti-human immunoglobulin/human immunoglobulin/(/sup 125/I)anti-human immunoglobulin 'sandwich' in a solid-phase radioimmunoassay to produce a standard curve which could be used to quantitate antigen-specific antibody of a particular immunoglobulin class was investigated. The amount of secondary antibody (SAb) bound was determined as a function of whether the primary antibody (PAb) was bound to its specific solid-phase antigen or by a solid-phase anti-human immunoglobulin. No significant difference between the two values was observed. Quantitation of anti-tetanus toxoid antibody by this method was in a good agreement with quantitative precipitin tests. Comparison of SAb binding as a function of the way the PAb is bound was extended to class-specific PAb by use of murine monoclonal antibodies to meningococcal antigens. In most cases somewhat greater binding of SAb occurred when PAb was bound to antigen, but in several cases where low avidity antibody and/or poor quality antigens were used, greater SAb binding occurred when PAb was bound by anti-mouse immunoglobulin. The results indicate that this approach may be useful as a general method for standardizing the SPRIA and other solid-phase immunoassays such as the ELISA to measure class-specific antibody.

  11. A Thermodynamically-consistent FBA-based Approach to Biogeochemical Reaction Modeling

    Science.gov (United States)

    Shapiro, B.; Jin, Q.

    2015-12-01

    Microbial rates are critical to understanding biogeochemical processes in natural environments. Recently, flux balance analysis (FBA) has been applied to predict microbial rates in aquifers and other settings. FBA is a genome-scale constraint-based modeling approach that computes metabolic rates and other phenotypes of microorganisms. This approach requires a prior knowledge of substrate uptake rates, which is not available for most natural microbes. Here we propose to constrain substrate uptake rates on the basis of microbial kinetics. Specifically, we calculate rates of respiration (and fermentation) using a revised Monod equation; this equation accounts for both the kinetics and thermodynamics of microbial catabolism. Substrate uptake rates are then computed from the rates of respiration, and applied to FBA to predict rates of microbial growth. We implemented this method by linking two software tools, PHREEQC and COBRA Toolbox. We applied this method to acetotrophic methanogenesis by Methanosarcina barkeri, and compared the simulation results to previous laboratory observations. The new method constrains acetate uptake by accounting for the kinetics and thermodynamics of methanogenesis, and predicted well the observations of previous experiments. In comparison, traditional methods of dynamic-FBA constrain acetate uptake on the basis of enzyme kinetics, and failed to reproduce the experimental results. These results show that microbial rate laws may provide a better constraint than enzyme kinetics for applying FBA to biogeochemical reaction modeling.

  12. Exploring Communication and Course Format: Conversation Frequency and Duration, Student Motives, and Perceived Teacher Approachability for Out-of-Class Contact

    Science.gov (United States)

    Brooks, Catherine F.; Young, Stacy L.

    2016-01-01

    This study explored how course instructional format (i.e., online, face-to-face, or hybrid) is related to the frequency and duration of out-of-class communication (OCC) between college instructors and students, to student motives for communicating with teachers, and to perceived teacher approachability for conversation outside of class. Though…

  13. Functional approach to a Class II patient with upper first molar impaction

    Directory of Open Access Journals (Sweden)

    Giacomo D′Orlandi

    2014-01-01

    Full Text Available The lack of the left first molar maxillary and the left second molar maxillary, caused respectively by impaction and agenesis is a very rare case, which determines an important occlusal imbalance and asymmetrical mandible movement. A gnatologic and functional orthodontic approach were planned to improve the retrognathic mandible and the muscular activity using kinesiograph and electromyography.

  14. Are In-Class Peer Leaders Effective in the Peer-Led Team-Learning Approach?

    Science.gov (United States)

    Schray, Keith; Russo, M. Jean; Egolf, Roger; Lademan, William; Gelormo, David

    2009-01-01

    Peer-led team learning (PLTL) has been widely adopted for enhanced learning in a variety of disciplines, mostly in introductory chemistry, but also in organic chemistry, as in this study (Tien, Roth, and Kampmeier 2002). This pedagogical approach forms student groups led by students who have previously done well in the course (standard peer…

  15. Neural network approach to time-dependent dividing surfaces in classical reaction dynamics

    Science.gov (United States)

    Schraft, Philippe; Junginger, Andrej; Feldmaier, Matthias; Bardakcioglu, Robin; Main, Jörg; Wunner, Günter; Hernandez, Rigoberto

    2018-04-01

    In a dynamical system, the transition between reactants and products is typically mediated by an energy barrier whose properties determine the corresponding pathways and rates. The latter is the flux through a dividing surface (DS) between the two corresponding regions, and it is exact only if it is free of recrossings. For time-independent barriers, the DS can be attached to the top of the corresponding saddle point of the potential energy surface, and in time-dependent systems, the DS is a moving object. The precise determination of these direct reaction rates, e.g., using transition state theory, requires the actual construction of a DS for a given saddle geometry, which is in general a demanding methodical and computational task, especially in high-dimensional systems. In this paper, we demonstrate how such time-dependent, global, and recrossing-free DSs can be constructed using neural networks. In our approach, the neural network uses the bath coordinates and time as input, and it is trained in a way that its output provides the position of the DS along the reaction coordinate. An advantage of this procedure is that, once the neural network is trained, the complete information about the dynamical phase space separation is stored in the network's parameters, and a precise distinction between reactants and products can be made for all possible system configurations, all times, and with little computational effort. We demonstrate this general method for two- and three-dimensional systems and explain its straightforward extension to even more degrees of freedom.

  16. Towards an unified microscopic approach of the description of the nuclear structure and reaction

    International Nuclear Information System (INIS)

    Hoang, Sy Than

    2009-09-01

    This thesis contains 3 main parts. The first one: nuclear matter. The motivation of the study is to establish a link between the bare nucleon-nucleon interaction and nuclear matter properties. The properties of nuclear matter are examined using finite range effective interactions either derived from the Brueckner theory or determined in a purely phenomenological way. Skyrme-type interactions are also used for comparison. We have focused our discussion on several main aspects: the pressure ins symmetric nuclear matter and in neutron matter, the density dependence of the symmetric energy S and the nuclear matter incompressibility. The second part: the structure of finite nuclei and of the inner crust of neutrons stars. We present the non-relativistic HF and HF-BCS approaches in coordinate representation using finite-range density-dependent interactions in both the mean field and pairing channels. An iterative scheme is used for solving the integral-differential HF equations. We have studied the doubly magic nuclei, the Sn isotopes and the possible occurrence of bubble structures in the nuclei O 22 , Si 34 , Ar 46 and Ar 68 . We have also examined the different zones of the inner crust of neutron stars. The third part: nuclear reactions. Using the same effective interactions derived from the Brueckner theory we have performed a coupled channel analysis of (p,n) charge exchange reactions at 35 and 45 MeV incident energies on Ca 48 , Zr 90 , Sn 120 and Pb 208 targets leading to isobaric analog states. (A.C.)

  17. Knowledge Management and World Class Manufacturing: an initial approach based on a literature review

    Directory of Open Access Journals (Sweden)

    Rafael de Carvalho Mendes

    Full Text Available ABSTRACT This paper presents the partial results of an ongoing research on the proposal of a methodology for the integration between Knowledge Management (KM and World Class Manufacturing (WCM. The initial investigation of theoretical and conceptual nature aimed at developing a comprehensive and current vision on KM, WCM, and how (or "whether" these constructs relate to one another. The primary sources for the literature review were Web of Science, Scopus, Emerald, Ebsco, SciELO and Spell, and the time frame was 2000 to 2016. The analysis of the selected papers showed that, although the initial WCM model evolved into a "new WCM" in the 2000s, the literature is still focused on the broad conceptual aspects and basic methods and tools, such as Total Quality Process, Total Productive Maintenance and Just-in-Time, conceived in the Toyota Production System, which shows the need for more studies focused on the current scenario of companies associated with the "new WCM" and its Methods and Tools. Only one article explicitly addressing the interaction between KM theories with WCM was found in the databases surveyed, thus reinforcing the lack of theoretical approximation of these constructs.

  18. Genotyping of major histocompatibility complex Class II DRB gene in Rohilkhandi goats by polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing

    Directory of Open Access Journals (Sweden)

    Kush Shrivastava

    2015-10-01

    Full Text Available Aim: To study the major histocompatibility complex (MHC Class II DRB1 gene polymorphism in Rohilkhandi goat using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP and nucleotide sequencing techniques. Materials and Methods: DNA was isolated from 127 Rohilkhandi goats maintained at sheep and goat farm, Indian Veterinary Research Institute, Izatnagar, Bareilly. A 284 bp fragment of exon 2 of DRB1 gene was amplified and digested using BsaI and TaqI restriction enzymes. Population genetic parameters were calculated using Popgene v 1.32 and SAS 9.0. The genotypes were then sequenced using Sanger dideoxy chain termination method and were compared with related breeds/species using MEGA 6.0 and Megalign (DNASTAR software. Results: TaqI locus showed three and BsaI locus showed two genotypes. Both the loci were found to be in Hardy–Weinberg equilibrium (HWE, however, population genetic parameters suggest that heterozygosity is still maintained in the population at both loci. Percent diversity and divergence matrix, as well as phylogenetic analysis revealed that the MHC Class II DRB1 gene of Rohilkhandi goats was found to be in close cluster with Garole and Scottish blackface sheep breeds as compared to other goat breeds included in the sequence comparison. Conclusion: The PCR-RFLP patterns showed population to be in HWE and absence of one genotype at one locus (BsaI, both the loci showed excess of one or the other homozygote genotype, however, effective number of alleles showed that allelic diversity is present in the population. Sequence comparison of DRB1 gene of Rohilkhandi goat with other sheep and goat breed assigned Rohilkhandi goat in divergence with Jamanupari and Angora goats.

  19. A Representational Approach to Knowledge and Multiple Skill Levels for Broad Classes of Computer Generated Forces

    Science.gov (United States)

    1997-12-01

    that I’ll turn my attention to that computer game we’ve talked so much about... Dave Van Veldhuizen and Scott Brown (soon-to-be Drs. Van Veldhuizen and...Industry Training Systems Conference. 1988. 37. Van Veldhuizen , D. A. and L. J Hutson. "A Design Methodology for Domain Inde- pendent Computer...proposed by Van Veld- huizen and Hutson (37), extends the general architecture to support both a domain- independent approach to implementing CGFs and

  20. The γp → na2+ (1320) → nρ0π+ reactions within an effective Lagrangian approach

    International Nuclear Information System (INIS)

    Huang, Yin; Xie, Jujun; He, Jun; Chen, Xurong; Zhang, Hongfei

    2014-01-01

    We investigate the tensor meson a 2 (1320) photon-production off proton in the γp → na 2 + (1320) and γp → nρ 0 π + reactions within the effective Lagrangian approach and isobar model. For γp → na 2 + (1320) reaction, by considering the contributions from only the t-channel π + exchange, we get a fairly good description of the current experimental data for the total cross-section. Based on the theoretical results of the γp → na 2 + (1320) reaction, we studied the role of a 2 (1320) meson in the γp → nρ 0 π + reaction, which mainly contributes to the γp → nπ + π + π - reaction. The latter reaction has been measured by the CLAS Collaboration at the photon energy E γ around 5.1 GeV. For the γp → nρ 0 π + reaction, we pay attention to the low photon energy region where the contribution from a 2 (1320) meson is dominant, while the contribution from the π 2 (1670) meson could be very small and hence can be neglected. The total cross-sections, invariant mass distribution and the Dalitz plot of γp → nρ 0 π + reaction are shown, which can be tested by future experiments. (author)

  1. An eHealth Approach to Reporting Allergic Reactions to Food and Closing the Knowledge Gap.

    Science.gov (United States)

    Munro, Christopher; Semic-Jusufagic, Aida; Pyrz, Katarzyna; Couch, Philip; Dunn-Galvin, Audrey; Peek, Niels; Themis, Marina; Mills, Clare; Buchan, Iain; Hourihane, Jonathan; Simpson, Angela

    2015-01-01

    There is an important knowledge gap in food allergy management in understanding the factors that determine allergic reactions to food, in gathering objective reports of reactions in real time, and in accessing patients' reaction-histories during consultations. We investigate how eHealth methods can close this knowledge gap. We report experiences with an online tool for reporting allergic reactions that we have developed as a web application. This application has been successfully validated by participants from Ireland and the UK, and is currently being used in a pilot where participants report allergic reactions in near-real time.

  2. Assessing the evolutionary history of the class Synurophyceae (Heterokonta) using molecular, morphometric, and paleobiological approaches.

    Science.gov (United States)

    Siver, Peter A; Jo, Bok Yeon; Kim, Jong Im; Shin, Woongghi; Lott, Anne Marie; Wolfe, Alexander P

    2015-06-01

    Heterokont algae of the class Synurophyceae, characterized by distinctive siliceous scales that cover the surface of the cell, are ecologically important in inland waters, yet their evolutionary history remains enigmatic. We explore phylogenetic relationships within this group of algae relative to geologic time, with a focus on evolution of siliceous components. We combined an expansive five-gene and time-calibrated molecular phylogeny of synurophyte algae with an extensive array of fossil specimens from the middle Eocene to infer evolutionary trends within the group. The group originated in the Jurassic approximately 157 million years ago (Ma), with the keystone genera Mallomonas and Synura diverging during the Early Cretaceous at 130 Ma. Mallomonas further splits into two major subclades, signaling the evolution of the V-rib believed to aid in the spacing and organization of scales on the cell covering. Synura also diverges into two primary subclades, separating taxa with forward-projecting spines on the scale from those with a keel positioned on the scale proper. Approximately one third of the fossil species are extinct, whereas the remaining taxa are linked to modern congeners. The taxonomy of synurophytes, which relies extensively on the morphology of the siliceous components, is largely congruent with molecular analyses. Scales of extinct synurophytes were significantly larger than those of modern taxa and may have played a role in their demise. In contrast, many fossil species linked to modern lineages were smaller in the middle Eocene, possibly reflecting growth in the greenhouse climatic state that characterized this geologic interval. © 2015 Botanical Society of America, Inc.

  3. A convergent approach to the total synthesis of telmisartan via a Suzuki cross-coupling reaction between two functionalized benzimidazoles.

    Science.gov (United States)

    Martin, Alex D; Siamaki, Ali R; Belecki, Katherine; Gupton, B Frank

    2015-02-06

    A direct and efficient total synthesis has been developed for telmisartan, a widely prescribed treatment for hypertension. This approach brings together two functionalized benzimidazoles using a high-yielding Suzuki reaction that can be catalyzed by either a homogeneous palladium source or graphene-supported palladium nanoparticles. The ability to perform the cross-coupling reaction was facilitated by the regio-controlled preparation of the 2-bromo-1-methylbenzimidazole precursor. This convergent approach provides telmisartan in an overall yield of 72% while circumventing many issues associated with previously reported processes.

  4. On a class of quantum Langevin equations and the question of approach to equilibrium

    International Nuclear Information System (INIS)

    Maassen, J.D.M.

    1982-01-01

    This thesis is concerned with a very simple 'open' quantum system, i.e. being in contact with the outer world. It is asked whether the motion of this system shows frictional behaviour in that it tends to thermal equilibrium. A partial positive answer is given to this question, more precisely, to the question if the solution of the quantum mechanical Langevin equation that describes the Lamb-model (a harmonic oscillator damped by coupling with a string), approaches an equilibrium state. In two sections, the classical and quantum Langevin equations are treated analogously. (Auth.)

  5. Supervised pre-processing approaches in multiple class variables classification for fish recruitment forecasting

    KAUST Repository

    Fernandes, José Antonio

    2013-02-01

    A multi-species approach to fisheries management requires taking into account the interactions between species in order to improve recruitment forecasting of the fish species. Recent advances in Bayesian networks direct the learning of models with several interrelated variables to be forecasted simultaneously. These models are known as multi-dimensional Bayesian network classifiers (MDBNs). Pre-processing steps are critical for the posterior learning of the model in these kinds of domains. Therefore, in the present study, a set of \\'state-of-the-art\\' uni-dimensional pre-processing methods, within the categories of missing data imputation, feature discretization and feature subset selection, are adapted to be used with MDBNs. A framework that includes the proposed multi-dimensional supervised pre-processing methods, coupled with a MDBN classifier, is tested with synthetic datasets and the real domain of fish recruitment forecasting. The correctly forecasting of three fish species (anchovy, sardine and hake) simultaneously is doubled (from 17.3% to 29.5%) using the multi-dimensional approach in comparison to mono-species models. The probability assessments also show high improvement reducing the average error (estimated by means of Brier score) from 0.35 to 0.27. Finally, these differences are superior to the forecasting of species by pairs. © 2012 Elsevier Ltd.

  6. Using a bayesian latent class model to evaluate the utility of investigating persons with negative polymerase chain reaction results for pertussis.

    Science.gov (United States)

    Tarr, Gillian A M; Eickhoff, Jens C; Koepke, Ruth; Hopfensperger, Daniel J; Davis, Jeffrey P; Conway, James H

    2013-07-15

    Pertussis remains difficult to control. Imperfect sensitivity of diagnostic tests and lack of specific guidance regarding interpretation of negative test results among patients with compatible symptoms may contribute to its spread. In this study, we examined whether additional pertussis cases could be identified if persons with negative pertussis test results were routinely investigated. We conducted interviews among 250 subjects aged ≤18 years with pertussis polymerase chain reaction (PCR) results reported from 2 reference laboratories in Wisconsin during July-September 2010 to determine whether their illnesses met the Centers for Disease Control and Prevention's clinical case definition (CCD) for pertussis. PCR validity measures were calculated using the CCD as the standard for pertussis disease. Two Bayesian latent class models were used to adjust the validity measures for pertussis detectable by 1) culture alone and 2) culture and/or more sensitive measures such as serology. Among 190 PCR-negative subjects, 54 (28%) had illnesses meeting the CCD. In adjusted analyses, PCR sensitivity and the negative predictive value were 1) 94% and 99% and 2) 43% and 87% in the 2 types of models, respectively. The models suggested that public health follow-up of reported pertussis patients with PCR-negative results leads to the detection of more true pertussis cases than follow-up of PCR-positive persons alone. The results also suggest a need for a more specific pertussis CCD.

  7. Using a dual safeguard web-based interactive teaching approach in an introductory physics class

    Directory of Open Access Journals (Sweden)

    Lie-Ming Li

    2015-03-01

    Full Text Available We modified the Just-in-Time Teaching approach and developed a dual safeguard web-based interactive (DGWI teaching system for an introductory physics course. The system consists of four instructional components that improve student learning by including warm-up assignments and online homework. Student and instructor activities involve activities both in the classroom and on a designated web site. An experimental study with control groups evaluated the effectiveness of the DGWI teaching method. The results indicate that the DGWI method is an effective way to improve students’ understanding of physics concepts, develop students’ problem-solving abilities through instructor-student interactions, and identify students’ misconceptions through a safeguard framework based on questions that satisfy teaching requirements and cover all of the course material. The empirical study and a follow-up survey found that the DGWI method increased student-teacher interaction and improved student learning outcomes.

  8. Spectroscopic approaches to resolving ambiguities of hyper-polarized NMR signals from different reaction cascades

    DEFF Research Database (Denmark)

    Jensen, Pernille Rose; Meier, Sebastian

    2016-01-01

    The influx of exogenous substrates into cellular reaction cascades on the seconds time scale is directly observable by NMR spectroscopy when using nuclear spin polarization enhancement. Conventional NMR assignment spectra for the identification of reaction intermediates are not applicable...... in these experiments due to the non-equilibrium nature of the nuclear spin polarization enhancement. We show that ambiguities in the intracellular identification of transient reaction intermediates can be resolved by experimental schemes using site-specific isotope labelling, optimised referencing and response...

  9. A Computer-Assisted Personalized Approach in an Undergraduate Plant Physiology Class1

    Science.gov (United States)

    Artus, Nancy N.; Nadler, Kenneth D.

    1999-01-01

    We used Computer-Assisted Personalized Approach (CAPA), a networked teaching and learning tool that generates computer individualized homework problem sets, in our large-enrollment introductory plant physiology course. We saw significant improvement in student examination performance with regular homework assignments, with CAPA being an effective and efficient substitute for hand-graded homework. Using CAPA, each student received a printed set of similar but individualized problems of a conceptual (qualitative) and/or quantitative nature with quality graphics. Because each set of problems is unique, students were encouraged to work together to clarify concepts but were required to do their own work for credit. Students could enter answers multiple times without penalty, and they were able to obtain immediate feedback and hints until the due date. These features increased student time on task, allowing higher course standards and student achievement in a diverse student population. CAPA handles routine tasks such as grading, recording, summarizing, and posting grades. In anonymous surveys, students indicated an overwhelming preference for homework in CAPA format, citing several features such as immediate feedback, multiple tries, and on-line accessibility as reasons for their preference. We wrote and used more than 170 problems on 17 topics in introductory plant physiology, cataloging them in a computer library for general access. Representative problems are compared and discussed. PMID:10198076

  10. A computer-assisted personalized approach in an undergraduate plant physiology class

    Science.gov (United States)

    Artus; Nadler

    1999-04-01

    We used Computer-Assisted Personalized Approach (CAPA), a networked teaching and learning tool that generates computer individualized homework problem sets, in our large-enrollment introductory plant physiology course. We saw significant improvement in student examination performance with regular homework assignments, with CAPA being an effective and efficient substitute for hand-graded homework. Using CAPA, each student received a printed set of similar but individualized problems of a conceptual (qualitative) and/or quantitative nature with quality graphics. Because each set of problems is unique, students were encouraged to work together to clarify concepts but were required to do their own work for credit. Students could enter answers multiple times without penalty, and they were able to obtain immediate feedback and hints until the due date. These features increased student time on task, allowing higher course standards and student achievement in a diverse student population. CAPA handles routine tasks such as grading, recording, summarizing, and posting grades. In anonymous surveys, students indicated an overwhelming preference for homework in CAPA format, citing several features such as immediate feedback, multiple tries, and on-line accessibility as reasons for their preference. We wrote and used more than 170 problems on 17 topics in introductory plant physiology, cataloging them in a computer library for general access. Representative problems are compared and discussed.

  11. A pedagogical approach to socially just relations in a Grade 11 Economics class

    Directory of Open Access Journals (Sweden)

    Zayd Waghid

    2016-05-01

    Full Text Available Post-apartheid schooling in South Africa is challenged with the task of contributing towards social justice, as has been evident from the emergence of a plethora of education policies following the promulgation of the South African Schools Act in 1996. One of the most significant ways in which social justice can be cultivated in schools, especially where exclusion and marginalisation have been in ascendancy for decades, is through improved pedagogical activities, which receive focus in this article. The article focuses on investigating how the learning goals for Grade 11 Economics with the aid of an educational technology, in particular Facebook, engender opportunities for socially just relations in the classroom. The researcher is concerned with how these learning goals are related to three underlying aspects of Economics education, namely sustainable development, equity (including equality and economic development, and how they may or may not engender opportunities for social justice. Critical discourse analysis is the research approach used to analyse learners' comments on Facebook in relation to their understandings of three films. It was found that it is possible to teach and learn education for social justice in the classroom. Learners treated one another equally; enacted their pedagogical relations equitably; and learnt to become economically aware of their society's developmental needs. Thus, it is recommended that education for social justice be cultivated in school classrooms through the use of Facebook.

  12. Robust Sensor Faults Reconstruction for a Class of Uncertain Linear Systems Using a Sliding Mode Observer: An LMI Approach

    International Nuclear Information System (INIS)

    Iskander, Boulaabi; Faycal, Ben Hmida; Moncef, Gossa; Anis, Sellami

    2009-01-01

    This paper presents a design method of a Sliding Mode Observer (SMO) for robust sensor faults reconstruction of systems with matched uncertainty. This class of uncertainty requires a known upper bound. The basic idea is to use the H ∞ concept to design the observer, which minimizes the effect of the uncertainty on the reconstruction of the sensor faults. Specifically, we applied the equivalent output error injection concept from previous work in Fault Detection and Isolation (FDI) scheme. Then, these two problems of design and reconstruction can be expressed and numerically formulate via Linear Matrix Inequalities (LMIs) optimization. Finally, a numerical example is given to illustrate the validity and the applicability of the proposed approach.

  13. Mass Transfer and Chemical Reaction Approach of the Kinetics of the Acetylation of Gadung Flour using Glacial Acetic Acid

    Directory of Open Access Journals (Sweden)

    Andri Cahyo Kumoro

    2015-03-01

    Full Text Available Acetylation is one of the common methods of modifying starch properties by introducing acetil (CH3CO groups to starch molecules at low temperatures. While most acetylation is conducted using starch as anhidroglucose source and acetic anhydride or vinyl acetate as nucleophilic agents, this work employ reactants, namely flour and glacial acetic acid. The purpose of this work are to study the effect of pH reaction and GAA/GF mass ratio on the rate of acetylation reaction and to determine its rate constants. The acetylation of gadung flour with glacial acetic acid in the presence of sodium hydroxide as a homogenous catalyst was studied at ambient temperature with pH ranging from 8-10 and different mass ratio of acetic acid : gadung flour (1:3; 1:4; and 1:5. It was found that increasing pH, lead to increase the degree of substitution, while increasing GAA/GF mass ratio caused such decreases in the degree of substitution, due to the hydrolysis of the acetylated starch. The desired starch acetylation reaction is accompanied by undesirable hydrolysis reaction of the acetylated starch after 40-50 minutes reaction time. Investigation of kinetics of the reaction observed that the value of mass transfer rate constant (Kcs is smaller than the surface reaction rate constant (k. Thus, it can be concluded that rate controlling step is mass transfer.  © 2015 BCREC UNDIP. All rights reservedReceived: 7th August 2014; Revised: 8th September 2014; Accepted: 14th September 2014How to Cite: Kumoro, A.C., Amelia, R. (2015. Mass Transfer and Chemical Reaction Approach of the Kinetics of the Acetylation of Gadung Flour using Glacial Acetic Acid. Bulletin of Chemical Reaction Engineering & Catalysis, 10 (1: 30-37. (doi:10.9767/bcrec.10.1.7181.30-37Permalink/DOI: http://dx.doi.org/10.9767/bcrec.10.1.7181.30-37

  14. 7Li(d,p)8Li transfer reaction in the NCSM/RGM approach

    Science.gov (United States)

    Raimondi, F.; Hupin, G.; Navrátil, P.; Quaglioni, S.

    2018-03-01

    Recently, we applied an ab initio method, the no-core shell model combined with the resonating group method, to the transfer reactions with light p-shell nuclei as targets and deuteron as the projectile. In particular, we studied the elastic scattering of deuterium on 7Li and the 7Li(d,p)8Li transfer reaction starting from a realistic two-nucleon interaction. In this contribution, we review of our main results on the 7Li(d,p)8Li transfer reaction, and we extend the study of the relevant reaction channels, by showing the dominant resonant phase shifts of the scattering matrix. We assess also the impact of the polarization effects of the deuteron below the breakup on the positive-parity resonant states in the reaction. For this purpose, we perform an analysis of the convergence trend of the phase and eigenphase shifts, with respect to the number of deuteron pseudostates included in the model space.

  15. Few-body semiclassical approach to nucleon transfer and emission reactions

    Directory of Open Access Journals (Sweden)

    Sultanov Renat A.

    2014-04-01

    Full Text Available A three-body semiclassical model is proposed to describe the nucleon transfer and emission reactions in a heavy-ion collision. In this model the two heavy particles, i.e. nuclear cores A1(ZA1, MA1 and A2(ZA2, MA2, move along classical trajectories R→1(t${{\\vec R}_1}\\left( t \\right$ and R→2(t${{\\vec R}_2}\\left( t \\right$ respectively, while the dynamics of the lighter neutron (n is considered from a quantum mechanical point of view. Here, Mi are the nucleon masses and Zi are the Coulomb charges of the heavy nuclei (i = 1, 2. A Faddeev-type semiclassical formulation using realistic paired nuclear-nuclear potentials is applied so that all three channels (elastic, rearrangement and break-up are described in a unified manner. In order to solve the time-dependent equations the Faddeev components of the total three-body wave-function are expanded in terms of the input and output channel target eigenfunctions. In the special case, when the nuclear cores are identical (A1 ≡ A2 and also the two-level approximation in the expansion over the target (subsystem functions is used, the time-dependent semiclassical Faddeev equations are resolved in an explicit way. To determine the realistic R→1(t${{\\vec R}_1}\\left( t \\right$ and R→2(t${{\\vec R}_2}\\left( t \\right$ trajectories of the nuclear cores, a self-consistent approach based on the Feynman path integral theory is applied.

  16. A modern approach for epitope prediction: identification of foot-and-mouth disease virus peptides binding bovine leukocyte antigen (BoLA) class I molecules

    DEFF Research Database (Denmark)

    Pandya, Mital; Rasmussen, Michael; Hansen, Andreas

    2015-01-01

    Major histocompatibility complex (MHC) class I molecules regulate adaptive immune responses through the presentation of antigenic peptides to CD8+ T cells. Polymorphisms in the peptide binding region of class I molecules determine peptide binding affinity and stability during antigen presentation......, and different antigen peptide motifs are associated with specific genetic sequences of class I molecules. Understanding bovine leukocyte antigen (BoLA), peptide-MHC class I binding specificities may facilitate development of vaccines or reagents for quantifying the adaptive immune response to intracellular...... pathogens, such as foot-and-mouth disease virus (FMDV). Six synthetic BoLA class I (BoLA-I) molecules were produced, and the peptide binding motif was generated for five of the six molecules using a combined approach of positional scanning combinatorial peptide libraries (PSCPLs) and neural network...

  17. Revisiting the Reaction Between Diaminomaleonitrile and Aromatic Aldehydes: a Green Chemistry Approach

    Directory of Open Access Journals (Sweden)

    Francisco León

    2006-11-01

    Full Text Available The reaction between diaminomaleonitrile (DAMN and aldehydes and the resulting monoimines are well known. Since the standard reaction conditions involve the use of toxic solvents (typically methanol, we have sought to apply green chemistry principles to this reaction by either using water as the solvent without any catalysts or employing “solvent-free” conditions. The monoimines derived from DAMN are of interest as precursors for obtaining different heterocyclic systems and linear polymers. The methodologies used have significant advantages with regards to cost and environmental considerations.

  18. Catalytic asymmetric diels-alder reaction of quinone imine ketals: a site-divergent approach.

    Science.gov (United States)

    Hashimoto, Takuya; Nakatsu, Hiroki; Maruoka, Keiji

    2015-04-07

    The catalytic asymmetric Diels-Alder reaction of quinone imine ketals with diene carbamates catalyzed by axially chiral dicarboxylic acids is reported herein. A variety of primary and secondary alkyl-substituted quinone derivatives which have not been applied in previous asymmetric quinone Diels-Alder reactions could be employed using this method. More importantly, we succeeded in developing a strategy to divert the reaction site in unsymmetrical 3-alkyl quinone imine ketals from the inherently favored unsubstituted C=C bond to the disfavored alkyl-substituted C=C bond. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Synchronization Control for a Class of Discrete-Time Dynamical Networks With Packet Dropouts: A Coding-Decoding-Based Approach.

    Science.gov (United States)

    Wang, Licheng; Wang, Zidong; Han, Qing-Long; Wei, Guoliang

    2017-09-06

    The synchronization control problem is investigated for a class of discrete-time dynamical networks with packet dropouts via a coding-decoding-based approach. The data is transmitted through digital communication channels and only the sequence of finite coded signals is sent to the controller. A series of mutually independent Bernoulli distributed random variables is utilized to model the packet dropout phenomenon occurring in the transmissions of coded signals. The purpose of the addressed synchronization control problem is to design a suitable coding-decoding procedure for each node, based on which an efficient decoder-based control protocol is developed to guarantee that the closed-loop network achieves the desired synchronization performance. By applying a modified uniform quantization approach and the Kronecker product technique, criteria for ensuring the detectability of the dynamical network are established by means of the size of the coding alphabet, the coding period and the probability information of packet dropouts. Subsequently, by resorting to the input-to-state stability theory, the desired controller parameter is obtained in terms of the solutions to a certain set of inequality constraints which can be solved effectively via available software packages. Finally, two simulation examples are provided to demonstrate the effectiveness of the obtained results.

  20. The application of individual approach in how to conduct aerobics classes with students of different levels of preparedness.

    Directory of Open Access Journals (Sweden)

    Barybina L.N.

    2012-09-01

    Full Text Available The aim of this work was to develop a system of classes in aerobics in high school with an individual approach. On this subject has been analyzed about 15 references. 105 students took part in an experiment. The technique, which combines fitness aerobics and step aerobics. The technique allows to take into account the physical capacity, functional differences, the level of preparedness and dealing with their needs, as well as to use an individual approach in the selection of means and methods of physical education. We propose the organization of activities in which the hall can simultaneously engage up to 5-6 subgroups: students with low fitness and low levels of coordination abilities, students with an average level of physical fitness and low levels of coordination abilities, students with high levels of physical fitness and low levels of coordination abilities, students with an average level of physical fitness and a high level of coordination abilities, students with high levels of physical fitness and coordination abilities.

  1. Towards an unified microscopic approach of the description of the nuclear structure and reaction

    International Nuclear Information System (INIS)

    Hoang, Sy-Than

    2009-01-01

    This thesis contains 3 main parts: 1. Nuclear matter: The properties of nuclear matter are examined using finite range effective interactions, either derived from the Brueckner theory (M3Y-type interactions) or determined in a purely phenomenological way (Gogny-type interactions). Skyrme-type interactions are also used for comparison. The motivation of the study is to establish a link between the bare NN interaction and nuclear matter properties via the effective Brueckner G-matrix parameterized in the M3Y form. We have concentrated our discussion on several main aspects: the pressure in symmetric nuclear matter and in neutron matter, the density dependence of the symmetry energy S, the neutron star cooling, and the nuclear matter incompressibility for the symmetric and asymmetric nuclear matter. 2. Structure of finite nuclei and of the inner crust of neutron stars: We present the non-relativistic HF and HF-BCS approaches in coordinate representation using finite-range density-dependent interactions in both the mean field and pairing channels. The method for solving the HF equations in coordinate space is presented. We limit the study to the spherical symmetry case. An iterative scheme is used for solving the integro-differential HF equations. We adopt the method of Brueckner-Gammel-Weizner which is free of poles in the local equivalent potentials, in contrast to the usually used Vautherin-Veneroni method. Alternatively, we have developed a method using a basis of spherical Bessel functions. The latter method is useful for treating systems containing many nucleons in large boxes like the Wigner-Seitz (WS) cells of the neutron star inner crust. We have thus studied, using the effective interactions mentioned above, the doubly magic nuclei, the Sn isotopes, and the possible occurrence of bubble structures in the nuclei 22 O, 34 Si, 46 Ar and 68 Ar. We also present for the first time a study of Wigner-Seitz cells in the inner crust of neutron stars using finite range

  2. Sodium-Water Reaction approach and mastering for ASTRID Steam Generator design

    International Nuclear Information System (INIS)

    Saez, Manuel; Allou, Alexandre; Beauchamp, François; Bertrand, Carole; Rodriguez, Gilles; Menou, Sylvain; Prele, Gérard

    2013-01-01

    Conclusions: • Modular Steam Generator concept selected for ASTRID: → Brings flexibility for the expertise of failed modules after their removal; → Intrinsically limit the mechanical consequences of a postulated large Sodium-Water Reaction. • Sodium-Water-Air Reaction studies include both prevention and mitigation aspects, with dedicated tools to be developed through R&D. • Regarding Safety analysis, the possibility to move from the scenario of instantaneous failure of the whole Steam Generator tube bundle toward a scenario with sequenced failure needs to be investigated. • The Steam Generator is one of the key components in the Sodium-cooled Fast Reactor system for it provides an interface between sodium and water. The design objective for the Steam Generator is related to the improvement of mastering of Sodium-Water Reaction. • Potential Sodium-Water Reactions can be eliminated by adopting a Gas based Power Conversion System

  3. Constrained reaction volume approach for studying chemical kinetics behind reflected shock waves

    KAUST Repository

    Hanson, Ronald K.; Pang, Genny A.; Chakraborty, Sreyashi; Ren, Wei; Wang, Shengkai; Davidson, David Frank

    2013-01-01

    We report a constrained-reaction-volume strategy for conducting kinetics experiments behind reflected shock waves, achieved in the present work by staged filling in a shock tube. Using hydrogen-oxygen ignition experiments as an example, we

  4. Microscopic approach to the theory of light nuclei and to simple nuclear reactions

    International Nuclear Information System (INIS)

    Baz', L.I.; Filippov, G.F.

    1976-01-01

    The results of calculations for the properties of light nuclei and simple nuclear reactions using the Schrodinger multinucleon equation involving the realistic nucleon-nucleon interaction are reviewed. It is noted that the theory for the A(<=)4 nuclei is practically complete at present. The reasons for the good agreement between the theoretical and experimental cross sections of nuclear reactions are given. The programme of a correct separation of the nuclear collective degree of freedom are discussed in detail

  5. Mass transfer and slag-metal reaction in ladle refining : a CFD approach

    OpenAIRE

    Ramström, Eva

    2009-01-01

      In order to optimise the ladle treatment mass transfer modelling of aluminium addition and homogenisation time was carried out. It was stressed that incorporating slag-metal reactions into the mass transfer modelling strongly would enhance the reliability and amount of information to be analyzed from the CFD calculations.   In the present work, a thermodynamic model taking all the involved slag metal reactions into consideration was incorporated into a 2-D fluid flow model of an argon stirr...

  6. A Gibbs Energy Minimization Approach for Modeling of Chemical Reactions in a Basic Oxygen Furnace

    Science.gov (United States)

    Kruskopf, Ari; Visuri, Ville-Valtteri

    2017-12-01

    In modern steelmaking, the decarburization of hot metal is converted into steel primarily in converter processes, such as the basic oxygen furnace. The objective of this work was to develop a new mathematical model for top blown steel converter, which accounts for the complex reaction equilibria in the impact zone, also known as the hot spot, as well as the associated mass and heat transport. An in-house computer code of the model has been developed in Matlab. The main assumption of the model is that all reactions take place in a specified reaction zone. The mass transfer between the reaction volume, bulk slag, and metal determine the reaction rates for the species. The thermodynamic equilibrium is calculated using the partitioning of Gibbs energy (PGE) method. The activity model for the liquid metal is the unified interaction parameter model and for the liquid slag the modified quasichemical model (MQM). The MQM was validated by calculating iso-activity lines for the liquid slag components. The PGE method together with the MQM was validated by calculating liquidus lines for solid components. The results were compared with measurements from literature. The full chemical reaction model was validated by comparing the metal and slag compositions to measurements from industrial scale converter. The predictions were found to be in good agreement with the measured values. Furthermore, the accuracy of the model was found to compare favorably with the models proposed in the literature. The real-time capability of the proposed model was confirmed in test calculations.

  7. DisoMCS: Accurately Predicting Protein Intrinsically Disordered Regions Using a Multi-Class Conservative Score Approach.

    Directory of Open Access Journals (Sweden)

    Zhiheng Wang

    Full Text Available The precise prediction of protein intrinsically disordered regions, which play a crucial role in biological procedures, is a necessary prerequisite to further the understanding of the principles and mechanisms of protein function. Here, we propose a novel predictor, DisoMCS, which is a more accurate predictor of protein intrinsically disordered regions. The DisoMCS bases on an original multi-class conservative score (MCS obtained by sequence-order/disorder alignment. Initially, near-disorder regions are defined on fragments located at both the terminus of an ordered region connecting a disordered region. Then the multi-class conservative score is generated by sequence alignment against a known structure database and represented as order, near-disorder and disorder conservative scores. The MCS of each amino acid has three elements: order, near-disorder and disorder profiles. Finally, the MCS is exploited as features to identify disordered regions in sequences. DisoMCS utilizes a non-redundant data set as the training set, MCS and predicted secondary structure as features, and a conditional random field as the classification algorithm. In predicted near-disorder regions a residue is determined as an order or a disorder according to the optimized decision threshold. DisoMCS was evaluated by cross-validation, large-scale prediction, independent tests and CASP (Critical Assessment of Techniques for Protein Structure Prediction tests. All results confirmed that DisoMCS was very competitive in terms of accuracy of prediction when compared with well-established publicly available disordered region predictors. It also indicated our approach was more accurate when a query has higher homologous with the knowledge database.The DisoMCS is available at http://cal.tongji.edu.cn/disorder/.

  8. Lipidomic approach to identify patterns in phospholipid profiles and define class differences in mammary epithelial and breast cancer cells.

    Science.gov (United States)

    Dória, M Luísa; Cotrim, Zita; Macedo, Bárbara; Simões, Cláudia; Domingues, Pedro; Helguero, Luisa; Domingues, M Rosário

    2012-06-01

    Breast cancer is the leading cause of cancer-related deaths in women. Altered cellular functions of cancer cells lead to uncontrolled cellular growth and morphological changes. Cellular biomembranes are intimately involved in the regulation of cell signaling; however, they remain largely understudied. Phospholipids (PLs) are the main constituents of biological membranes and play important functional, structural and metabolic roles. The aim of this study was to establish if patterns in the PL profiles of mammary epithelial cells and breast cancer cells differ in relation to degree of differentiation and metastatic potential. For this purpose, PLs were analyzed using a lipidomic approach. In brief, PLs were extracted using Bligh and Dyer method, followed by a separation of PL classes by thin layer chromatography, and subsequent analysis by mass spectrometry (MS). Differences and similarities were found in the relative levels of PL content between mammary epithelial and breast cancer cells and between breast cancer cells with different levels of aggressiveness. When compared to the total PL content, phosphatidylcholine levels were reduced and lysophosphatydilcholines increased in the more aggressive cancer cells; while phosphatidylserine levels remained unchanged. MS analysis showed alterations in the classes of phosphatidylcholine, lysophosphatidylcholine, sphingomyelin, and phosphatidylinositides. In particular, the phosphatidylinositides, which are signaling molecules that affect proliferation, survival, and migration, showed dramatic alterations in their profile, where an increase of phosphatdylinositides saturated fatty acids chains and a decrease in C20 fatty acids in cancer cells compared with mammary epithelial cells was observed. At present, information about PL changes in cancer progression is lacking. Therefore, these data will be useful as a starting point to define possible PLs with prospective as biomarkers and disclose metabolic pathways with potential

  9. In Vivo Lighted Fluorescence via Fenton Reaction: Approach for Imaging of Hydrogen Peroxide in Living Systems.

    Science.gov (United States)

    Liu, Changhui; Chen, Weiju; Qing, Zhihe; Zheng, Jing; Xiao, Yue; Yang, Sheng; Wang, Lili; Li, Yinhui; Yang, Ronghua

    2016-04-05

    By virtue of its high sensitivity and rapidity, Fenton reaction has been demonstrated as a powerful tool for in vitro biochemical analysis; however, in vivo applications of Fenton reaction still remain to be exploited. Herein, we report, for the first time, the design, formation and testing of Fenton reaction for in vivo fluorescence imaging of hydrogen peroxide (H2O2). To realize in vivo fluorescence imaging of H2O2 via Fenton reaction, a functional nanosphere, Fc@MSN-FDNA/PTAD, is fabricated from mesoporous silica nanoparticle (MSN), a Fenton reagent of ferrocene (Fc), ROX-labeled DNA (FDNA), and a cationic perylene derivative (PTAD). The ferrocene molecules are locked in the pore entrances of MSN, and exterior of MSN is covalently immobilized with FDNA. As a key part, PTAD acts as not only the gatekeeper of MSN but also the efficient quencher of ROX. H2O2 can permeate into the nanosphere and react with ferrocene to product hydroxyl radical (·OH) via Fenton reaction, which cleaves FDNA to detach ROX from PTAD, thus in turn, lights the ROX fluorescence. Under physiological condition, H2O2 can be determined from 5.0 nM to 1.0 μM with a detection limit of 2.4 nM. Because of the rapid kinetics of Fenton reaction and high specificity for H2O2, the proposed method meets the requirement for real applications. The feasibility of Fc@MSN-FDNA/PTAD for in vivo applications is demonstrated for fluorescence imaging of exogenous and endogenous H2O2 in cells and mice. We expect that this work will not only contribute to the H2O2-releated studies but also open up a new way to exploit in vivo Fenton reaction for biochemical research.

  10. Pre-recombination quenching of the radiation induced fluorescence as the approach to study kinetics of ion-molecular reactions

    International Nuclear Information System (INIS)

    Borovkov, V.I.; Ivanishko, I.S.

    2011-01-01

    This study deals with the geminate ion recombination in the presence of bulk scavengers, that is the so-called scavenger problem, as well as with the effect of the scavenging reaction on the radiation-induced recombination fluorescence. have proposed a method to determine the rate constant of the bulk reaction between neutral scavengers and one of the geminate ions if the ion-molecular reaction prevented the formation of electronically excited states upon recombination involving a newly formed ion. If such pre-recombination quenching of the radiation-induced fluorescence took place, it manifested itself as a progressive decrease in the decay of the fluorescence intensity. The relative change in the fluorescence decay as caused by the scavengers was believed to be closely related to the kinetics of the scavenging reaction. The goal of the present study is to support this method, both computationally and experimentally because there are two factors, which cast doubt on the intuitively obvious approach to the scavenger problem: spatial correlations between the particles involved and the drift of the charged reagent in the electric field of its geminate partner. Computer simulation of geminate ions recombination with an explicit modeling of the motion trajectories of scavengers has been performed for media of low dielectric permittivity, i.e. for the maximal Coulomb interaction between the ions. The simulation has shown that upon continuous diffusion of the particles involved, the joint effect of the two above factors can be considered as insignificant with a high accuracy. Besides, it is concluded then that the method of pre-recombination quenching could be applied to study parallel and consecutive reactions where the yields of excited states in the reaction pathways are different with the use of very simple analytical relations of the formal chemical kinetics. The conclusion has been confirmed experimentally by the example of the reactions of electron transfer from

  11. A computational approach to extinction events in chemical reaction networks with discrete state spaces.

    Science.gov (United States)

    Johnston, Matthew D

    2017-12-01

    Recent work of Johnston et al. has produced sufficient conditions on the structure of a chemical reaction network which guarantee that the corresponding discrete state space system exhibits an extinction event. The conditions consist of a series of systems of equalities and inequalities on the edges of a modified reaction network called a domination-expanded reaction network. In this paper, we present a computational implementation of these conditions written in Python and apply the program on examples drawn from the biochemical literature. We also run the program on 458 models from the European Bioinformatics Institute's BioModels Database and report our results. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Modeling heat dissipation at the nanoscale: an embedding approach for chemical reaction dynamics on metal surfaces.

    Science.gov (United States)

    Meyer, Jörg; Reuter, Karsten

    2014-04-25

    We present an embedding technique for metallic systems that makes it possible to model energy dissipation into substrate phonons during surface chemical reactions from first principles. The separation of chemical and elastic contributions to the interaction potential provides a quantitative description of both electronic and phononic band structure. Application to the dissociation of O2 at Pd(100) predicts translationally "hot" oxygen adsorbates as a consequence of the released adsorption energy (ca. 2.6 eV). This finding questions the instant thermalization of reaction enthalpies generally assumed in models of heterogeneous catalysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Field theoretical approach to proton-nucleus reactions. I - One step inelastic scattering

    International Nuclear Information System (INIS)

    Eiras, A.; Kodama, T.; Nemes, M.C.

    1988-01-01

    In this work we obtain a closed form expression to the double differential cross section for one step proton-nucleus reaction within a field theoretical framework. Energy and momentum conservation as well as nuclear structure effects are consistently taken into account within the field theoretical eikonal approximation. In our formulation the kinematics of such reaction is not dominated by the free nucleon-nucleon cross section but a new factor which we call relativistic differential cross section in a Born Approximation. (author) [pt

  14. An improved approach to measuring drug innovation finds steady rates of first-in-class pharmaceuticals, 1987-2011.

    Science.gov (United States)

    Lanthier, Michael; Miller, Kathleen L; Nardinelli, Clark; Woodcock, Janet

    2013-08-01

    For more than a decade, industry analysts and policy makers have raised concerns about declining pharmaceutical innovation, citing declining numbers of new molecular entities (NMEs) approved in the United States each year. Yet there is little consensus on whether this is the best measure of "innovation." We examined NME approvals during 1987-2011 and propose the three distinct subcategories of NMEs--first-in-class, advance-in-class, and addition-to-class--to provide more nuanced and informative insights into underlying trends. We found that trends in NME approvals were largely driven by addition-to-class, or "me too," drug approvals, while first-in-class approvals remained fairly steady over the study period. Moreover, the higher proportion of first-in-class drug approvals over the most recent decade is an encouraging sign of the health of the industry as a whole.

  15. Management of Skeletal Class III Malocclusion with a Combined Approach of Facemask Therapy & Fixed Orthodontic Treatment - A Case Report

    Directory of Open Access Journals (Sweden)

    Shraddha Subhash Shetti

    2013-01-01

    Full Text Available A case report of an adolescent girl with a skeletal Class III malocclusion is presented. The associated clinical features of skeletal Class III are presented and management of such condition is discussed. The need for early identification and intervention of the skeletal Class III malocclusion is universally accepted by dentofacial orthopaedicians. Early intervention is associated with a better orthopedic response. Thus, treatment in the mixed or early permanent dentition can produce favorable results. Overcorrection of skeletal class III is recommended because treated patients grow similar to untreated Class III patients after treatment. Functional orthopaedic treatment rendered at an appropriate age ensures desired results in most cases. The intent of this article is to discuss the non-surgical treatment of a skeletal class III malocclusion along with a rationale of orthodontic management of such patients.

  16. Machine Learning-Assisted Network Inference Approach to Identify a New Class of Genes that Coordinate the Functionality of Cancer Networks.

    Science.gov (United States)

    Ghanat Bari, Mehrab; Ung, Choong Yong; Zhang, Cheng; Zhu, Shizhen; Li, Hu

    2017-08-01

    Emerging evidence indicates the existence of a new class of cancer genes that act as "signal linkers" coordinating oncogenic signals between mutated and differentially expressed genes. While frequently mutated oncogenes and differentially expressed genes, which we term Class I cancer genes, are readily detected by most analytical tools, the new class of cancer-related genes, i.e., Class II, escape detection because they are neither mutated nor differentially expressed. Given this hypothesis, we developed a Machine Learning-Assisted Network Inference (MALANI) algorithm, which assesses all genes regardless of expression or mutational status in the context of cancer etiology. We used 8807 expression arrays, corresponding to 9 cancer types, to build more than 2 × 10 8 Support Vector Machine (SVM) models for reconstructing a cancer network. We found that ~3% of ~19,000 not differentially expressed genes are Class II cancer gene candidates. Some Class II genes that we found, such as SLC19A1 and ATAD3B, have been recently reported to associate with cancer outcomes. To our knowledge, this is the first study that utilizes both machine learning and network biology approaches to uncover Class II cancer genes in coordinating functionality in cancer networks and will illuminate our understanding of how genes are modulated in a tissue-specific network contribute to tumorigenesis and therapy development.

  17. Optimization of reaction parameters for the electrochemical oxidation of lidocaine with a Design of Experiments approach

    NARCIS (Netherlands)

    Gul, Turan; Bischoff, Rainer; Permentier, Hjalmar

    2015-01-01

    Identification of potentially toxic oxidative drug metabolites is a crucial step in the development of new drugs. Electrochemical methods are useful to study oxidative drug metabolism, but are not widely used to synthesize metabolites for follow-up studies. Careful optimization of reaction

  18. Combined Geometric and Neural Network Approach to Generic Fault Diagnosis in Satellite Reaction Wheels

    DEFF Research Database (Denmark)

    Baldi, P.; Blanke, Mogens; Castaldi, P.

    2015-01-01

    This paper suggests a novel diagnosis scheme for detection, isolation and estimation of faults affecting satellite reaction wheels. Both spin rate measurements and actuation torque defects are dealt with. The proposed system consists of a fault detection and isolation module composed by a bank of...

  19. Class-first analysis in a continuum: an approach to the complexities of schools, society, and insurgent science

    Science.gov (United States)

    Valdiviezo, Laura Alicia

    2010-06-01

    This essay addresses Katherine Richardson Bruna's paper: Mexican Immigrant Transnational Social Capital and Class Transformation: Examining the Role of Peer Mediation in Insurgent Science, through five main points . First, I offer a comparison between the traditional analysis of classism in Latin America and Richardson Bruna's call for a class-first analysis in the North American social sciences where there has been a tendency to obviate the specific examination of class relations and class issues. Secondly, I discuss that a class-first analysis solely cannot suffice to depict the complex dimensions in the relations of schools and society. Thus, I suggest a continuum in the class-first analysis. Third, I argue that social constructions surrounding issues of language, ethnicity, and gender necessarily intersect with issues of class and that, in fact, those other constructions offer compatible epistemologies that aid in representing the complexity of social and institutional practices in the capitalist society. Richardson Bruna's analysis of Augusto's interactions with his teacher and peers in the science class provides a fourth point of discussion in this essay. As a final point in my response I discuss Richardson Bruna's idea of making accessible class-first analysis knowledge to educators and especially to science teachers.

  20. Modelling, Simulation, Animation, and Real-Time Control (Mosart) for a Class of Electromechanical Systems: A System-Theoretic Approach

    Science.gov (United States)

    Rodriguez, Armando A.; Metzger, Richard P.; Cifdaloz, Oguzhan; Dhirasakdanon, Thanate; Welfert, Bruno

    2004-01-01

    This paper describes an interactive modelling, simulation, animation, and real-time control (MoSART) environment for a class of 'cart-pendulum' electromechanical systems that may be used to enhance learning within differential equations and linear algebra classes. The environment is useful for conveying fundamental mathematical/systems concepts…

  1. Practical approaches to the ESI-MS analysis of catalytic reactions.

    Science.gov (United States)

    Yunker, Lars P E; Stoddard, Rhonda L; McIndoe, J Scott

    2014-01-01

    Electrospray ionization mass spectrometry (ESI-MS) is a soft ionization technique commonly coupled with liquid or gas chromatography for the identification of compounds in a one-time view of a mixture (for example, the resulting mixture generated by a synthesis). Over the past decade, Scott McIndoe and his research group at the University of Victoria have developed various methodologies to enhance the ability of ESI-MS to continuously monitor catalytic reactions as they proceed. The power, sensitivity and large dynamic range of ESI-MS have allowed for the refinement of several homogenous catalytic mechanisms and could potentially be applied to a wide range of reactions (catalytic or otherwise) for the determination of their mechanistic pathways. In this special feature article, some of the key challenges encountered and the adaptations employed to counter them are briefly reviewed. Copyright © 2014 John Wiley & Sons, Ltd.

  2. Constrained reaction volume approach for studying chemical kinetics behind reflected shock waves

    KAUST Repository

    Hanson, Ronald K.

    2013-09-01

    We report a constrained-reaction-volume strategy for conducting kinetics experiments behind reflected shock waves, achieved in the present work by staged filling in a shock tube. Using hydrogen-oxygen ignition experiments as an example, we demonstrate that this strategy eliminates the possibility of non-localized (remote) ignition in shock tubes. Furthermore, we show that this same strategy can also effectively eliminate or minimize pressure changes due to combustion heat release, thereby enabling quantitative modeling of the kinetics throughout the combustion event using a simple assumption of specified pressure and enthalpy. We measure temperature and OH radical time-histories during ethylene-oxygen combustion behind reflected shock waves in a constrained reaction volume and verify that the results can be accurately modeled using a detailed mechanism and a specified pressure and enthalpy constraint. © 2013 The Combustion Institute.

  3. Reaction of Diazo Compounds with Difluorocarbene: An Efficient Approach towards 1,1-Difluoroolefins.

    Science.gov (United States)

    Zhang, Zhikun; Yu, Weizhi; Wu, Chenggui; Wang, Chengpeng; Zhang, Yan; Wang, Jianbo

    2016-01-04

    A transition-metal-free difluoromethylenation of diazo compounds that proceeds under mild conditions has been developed and is based on the use of TMSCF2 Br as the difluoromethylene source and tetrabutylammonium bromide (TBAB) as the promoter. The chemoselective formal carbene dimerization reaction is achieved owing to the electronic properties and the relative stability of the difluorocarbene intermediate. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Practice and effectiveness of web-based problem-based learning approach in a large class-size system: A comparative study.

    Science.gov (United States)

    Ding, Yongxia; Zhang, Peili

    2018-06-12

    Problem-based learning (PBL) is an effective and highly efficient teaching approach that is extensively applied in education systems across a variety of countries. This study aimed to investigate the effectiveness of web-based PBL teaching pedagogies in large classes. The cluster sampling method was used to separate two college-level nursing student classes (graduating class of 2013) into two groups. The experimental group (n = 162) was taught using a web-based PBL teaching approach, while the control group (n = 166) was taught using conventional teaching methods. We subsequently assessed the satisfaction of the experimental group in relation to the web-based PBL teaching mode. This assessment was performed following comparison of teaching activity outcomes pertaining to exams and self-learning capacity between the two groups. When compared with the control group, the examination scores and self-learning capabilities were significantly higher in the experimental group (P web-based PBL teaching approach. In a large class-size teaching environment, the web-based PBL teaching approach appears to be more optimal than traditional teaching methods. These results demonstrate the effectiveness of web-based teaching technologies in problem-based learning. Copyright © 2018. Published by Elsevier Ltd.

  5. A Hamiltonian viewpoint in the modeling of switching power converters : A systematic modeling procedure of a large class of switching power converters using the Hamiltonian approach

    NARCIS (Netherlands)

    Escobar, Gerardo; Schaft, Arjan J. van der; Ortega, Romeo

    1999-01-01

    In this paper we show how, using the Hamiltonian formalism, we can systematically derive mathematical models that describe the behaviour of a large class of switching power converters, including the "Boost", "Buck", "Buck-Boost", "Čuk" and "Flyback" converters. We follow the approach earlier

  6. Sex-related and non-sex-related comorbidity subtypes of tic disorders: a latent class approach.

    Science.gov (United States)

    Rodgers, S; Müller, M; Kawohl, W; Knöpfli, D; Rössler, W; Castelao, E; Preisig, M; Ajdacic-Gross, V

    2014-05-01

    Recent evidence suggests that there may be more than one Gilles de la Tourette syndrome (GTS)/tic disorder phenotype. However, little is known about the common patterns of these GTS/tic disorder-related comorbidities. In addition, sex-specific phenomenological data of GTS/tic disorder-affected adults are rare. Therefore, this community-based study used latent class analyses (LCA) to investigate sex-related and non-sex-related subtypes of GTS/tic disorders and their most common comorbidities. The data were drawn from the PsyCoLaus study (n = 3691), a population-based survey conducted in Lausanne, Switzerland. LCA were performed on the data of 80 subjects manifesting motor/vocal tics during their childhood/adolescence. Comorbid attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, depressive, phobia and panic symptoms/syndromes comprised the selected indicators. The resultant classes were characterized by psychosocial correlates. In LCA, four latent classes provided the best fit to the data. We identified two male-related classes. The first class exhibited both ADHD and depression. The second class comprised males with only depression. Class three was a female-related class depicting obsessive thoughts/compulsive acts, phobias and panic attacks. This class manifested high psychosocial impairment. Class four had a balanced sex proportion and comorbid symptoms/syndromes such as phobias and panic attacks. The complementary occurrence of comorbid obsessive thoughts/compulsive acts and ADHD impulsivity was remarkable. To the best of our knowledge, this is the first study applying LCA to community data of GTS symptoms/tic disorder-affected persons. Our findings support the utility of differentiating GTS/tic disorder subphenotypes on the basis of comorbid syndromes. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

  7. Not all experiences of (inauthenticity are created equal: A latent class analysis approach(retitled Identifying Differences in the Experience of (InAuthenticity: A Latent Class Analysis Approach

    Directory of Open Access Journals (Sweden)

    Alison P. Lenton

    2014-07-01

    Full Text Available Generally, psychologists consider state authenticity– that is, the subjective sense of being one’s true self – to be a unitary and unidimensional construct, such that (a the phenomenological experience of authenticity is thought to be similar no matter its trigger, and (b inauthenticity is thought to be simply the opposing pole (on the same underlying construct of authenticity. Using latent class analysis, we put this conceptualization to a test. In order to avoid over-reliance on a Western conceptualization of authenticity, we used a cross-cultural sample (N = 543, comprising participants from Western, South-Asian, East-Asian, and South-East Asian cultures. Participants provided either a narrative in which the described when they felt most like being themselves or one in which they described when they felt least like being themselves. The analysis identified six distinct classes of experiences: two authenticity classes ('everyday' and 'extraordinary', three inauthenticity classes ('self-conscious,' 'deflated,' and 'extraordinary', and a class representing convergence between authenticity and inauthenticity. The classes were phenomenologically distinct, especially with respect to negative affect, private and public self-consciousness, and self-esteem. Furthermore, relatively more interdependent cultures were less likely to report experiences of extraordinary (inauthenticity than relatively more independent cultures. Understanding the many facets of (inauthenticity may enable researchers to connect different findings and explain why the attainment of authenticity can be difficult.

  8. Reversible logic gates based on enzyme-biocatalyzed reactions and realized in flow cells: a modular approach.

    Science.gov (United States)

    Fratto, Brian E; Katz, Evgeny

    2015-05-18

    Reversible logic gates, such as the double Feynman gate, Toffoli gate and Peres gate, with 3-input/3-output channels are realized using reactions biocatalyzed with enzymes and performed in flow systems. The flow devices are constructed using a modular approach, where each flow cell is modified with one enzyme that biocatalyzes one chemical reaction. The multi-step processes mimicking the reversible logic gates are organized by combining the biocatalytic cells in different networks. This work emphasizes logical but not physical reversibility of the constructed systems. Their advantages and disadvantages are discussed and potential use in biosensing systems, rather than in computing devices, is suggested. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. An analytical approach to the forensic identification of different classes of new psychoactive substances (NPSs) in seized materials.

    Science.gov (United States)

    Strano Rossi, Sabina; Odoardi, Sara; Gregori, Adolfo; Peluso, Giuseppe; Ripani, Luigi; Ortar, Giorgio; Serpelloni, Giovanni; Romolo, Francesco Saverio

    2014-09-15

    New psychoactive substances (NPSs) are rapidly spreading worldwide, and forensic laboratories are often requested to identify new substances for which no reference standards or analytical data are available. This article describes an analytical approach that was adopted in Italy by a few collaborative centres of the Italian Early Warning System for Drugs, which has contributed many alerts for the identification of different classes of NPSs in the last 24 months. Seized crystals and powders were initially analysed via single quadrupole gas chromatography/mass spectrometry (GC/MS), followed by liquid chromatography/high-resolution mass spectrometry (LC/HRMS) in the positive electrospray ionisation (ESI) mode at 100,000 full width at half maximum resolution (FWHM) without fragmentation to elucidate the elemental compositions of unknown molecules. Different fragmentation voltages during LC/HRMS were applied to study the accurate masses of the obtained characteristic fragments. Nuclear magnetic resonance (NMR) analyses were performed to identify specific isomers when necessary. Some interesting examples of unknown NPSs from seizures later identified in our laboratories are reported, with special focus on those cases where analytical standards were not available during analyses. These cases include cathinones, such as 3-methylmethcathinone (3-MMC), methylone, bk-MBDB (butylone), 4-methylethcathinone (4-MEC), flephedrone, methylenedioxypyrovalerone (MDPV) and pentedrone, methoxetamine, apinaca or AKB48, benzydamine, meta-chlorophenylpiperazine (m-CPP), 5-MeO-N,N-dialkyl tryptamines, such as 5-MeO-DALT and 5-MeOMIPT, benzofurans, such as 6-APB and 4-APB, and diphenidine (identified for the first time in Europe). The identification of NPSs in confiscated materials was successfully achieved via GC/MS coupled with LC/HRMS and, in a few cases, NMR analyses. The availability of GC/MS libraries is of great assistance in the identification of new drugs. Alternatively, the study

  10. A Comparison of Deterministic and Stochastic Modeling Approaches for Biochemical Reaction Systems: On Fixed Points, Means, and Modes.

    Science.gov (United States)

    Hahl, Sayuri K; Kremling, Andreas

    2016-01-01

    In the mathematical modeling of biochemical reactions, a convenient standard approach is to use ordinary differential equations (ODEs) that follow the law of mass action. However, this deterministic ansatz is based on simplifications; in particular, it neglects noise, which is inherent to biological processes. In contrast, the stochasticity of reactions is captured in detail by the discrete chemical master equation (CME). Therefore, the CME is frequently applied to mesoscopic systems, where copy numbers of involved components are small and random fluctuations are thus significant. Here, we compare those two common modeling approaches, aiming at identifying parallels and discrepancies between deterministic variables and possible stochastic counterparts like the mean or modes of the state space probability distribution. To that end, a mathematically flexible reaction scheme of autoregulatory gene expression is translated into the corresponding ODE and CME formulations. We show that in the thermodynamic limit, deterministic stable fixed points usually correspond well to the modes in the stationary probability distribution. However, this connection might be disrupted in small systems. The discrepancies are characterized and systematically traced back to the magnitude of the stoichiometric coefficients and to the presence of nonlinear reactions. These factors are found to synergistically promote large and highly asymmetric fluctuations. As a consequence, bistable but unimodal, and monostable but bimodal systems can emerge. This clearly challenges the role of ODE modeling in the description of cellular signaling and regulation, where some of the involved components usually occur in low copy numbers. Nevertheless, systems whose bimodality originates from deterministic bistability are found to sustain a more robust separation of the two states compared to bimodal, but monostable systems. In regulatory circuits that require precise coordination, ODE modeling is thus still

  11. A Systems Approach towards an Intelligent and Self-Controlling Platform for Integrated Continuous Reaction Sequences**

    Science.gov (United States)

    Ingham, Richard J; Battilocchio, Claudio; Fitzpatrick, Daniel E; Sliwinski, Eric; Hawkins, Joel M; Ley, Steven V

    2015-01-01

    Performing reactions in flow can offer major advantages over batch methods. However, laboratory flow chemistry processes are currently often limited to single steps or short sequences due to the complexity involved with operating a multi-step process. Using new modular components for downstream processing, coupled with control technologies, more advanced multi-step flow sequences can be realized. These tools are applied to the synthesis of 2-aminoadamantane-2-carboxylic acid. A system comprising three chemistry steps and three workup steps was developed, having sufficient autonomy and self-regulation to be managed by a single operator. PMID:25377747

  12. Proposed research on class I components to test a general approach to accelerated aging under combined stress environments

    International Nuclear Information System (INIS)

    Gillen, K.T.; Salazar, E.A.; Frank, C.W.

    1977-04-01

    This report summarizes research on the aging of Class I components in environments representative of nuclear power plants. It discusses Class IE equipment used in nuclear power plants, typical environments encountered by Class IE components, and aging techniques used to qualify this equipment. General discussions of radiation chemistry of polymers and accelerated aging techniques are also included. Based on the inadequacies of present aging techniques for Class IE equipment, a proposal for an experimental program on electrical cables is presented. One of the main purposes of the proposed work is to obtain relevant data in two areas of particular concern--the effect of radiation dose rate on polymer degradation, and the importance of synergism for combined thermal and radiation environments. A new model that allows combined environment accelerated aging to be carried out is introduced, and it is shown how the experimental data to be generated can be used to test this model

  13. Examining the reaction of monetary policy to exchange rate changes: A nonlinear ARDL approach

    Science.gov (United States)

    Manogaran, Lavaneesvari; Sek, Siok Kun

    2017-04-01

    Previous studies showed the exchange rate changes can have significant impacts on macroeconomic performance. Over fluctuation of exchange rate may lead to economic instability. Hence, monetary policy rule tends to react to exchange rate changes. Especially, in emerging economies where the policy-maker tends to limit the exchange rate movement through interventions. In this study, we seek to investigate how the monetary policy rule reacts to exchange rate changes. The nonlinear autoregressive distributed lag (NARDL) model is applied to capture the asymmetric effect of exchange rate changes on monetary policy reaction function (interest rate). We focus the study in ASEAN5 countries (Indonesia, Malaysia, Philippines, Thailand and Singapore). The results indicated the existence of asymmetric effect of exchange rates changes on the monetary reaction function for all ASEAN5 countries in the long-run. Where, in majority of the cases the monetary policy is reacting to the appreciation and depreciation of exchange rate by raising the policy rate. This affirms the intervention of policymakers with the `fear of floating' behavior.

  14. Strategies for catalyst development: possibilities of the ``rational approach`` illustrated with partial oxidation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, W.; Schedel-Niedrig, T.; Schloegl, R. [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin (Germany). Abt. Oberflaechenphysik

    1998-12-31

    The paper discusses two petrochemical selective oxidation reactions namely the practised formation of styrene (STY) and the desired oxidative functionalisation of propane. The present knowledge about the mode of operation of oxide catalysts is critically considered. The dehydrogenation of ethylbenzene (EB) should be described by an oxidehydration with water acting as oxidant. The potential role of the coke formed during catalytic reaction as co-catalyst will be discussed. Selective oxidation is connected with the participation of lattice oxygen mechanism which transforms unselective gas phase oxygen into selective oxygen. The atomistic description of this process is still quite unclear as well as the electron structural properties of the activated oxygen atom. The Role of solid state acidity as compared to the role of lattice oxygen is much less well investigated modern multiphase-multielement oxide (MMO) catalysts. The rationale is that the significant efforts made to improve current MMO systems by chemical modifications can be very much more fruitful when in a first step the mode of action of a catalyst is clarified on the basis of suitable experiments. Such time-consuming experiments at the beginning of a campaign for catalyst improvement pay back their investment in later stages of the project when strategies of chemical development can be derived on grounds of understanding. (orig.)

  15. Linear matrix inequality approach to exponential synchronization of a class of chaotic neural networks with time-varying delays

    Science.gov (United States)

    Wu, Wei; Cui, Bao-Tong

    2007-07-01

    In this paper, a synchronization scheme for a class of chaotic neural networks with time-varying delays is presented. This class of chaotic neural networks covers several well-known neural networks, such as Hopfield neural networks, cellular neural networks, and bidirectional associative memory networks. The obtained criteria are expressed in terms of linear matrix inequalities, thus they can be efficiently verified. A comparison between our results and the previous results shows that our results are less restrictive.

  16. Pain management for children with cerebral palsy in school settings in two cultures: action and reaction approaches.

    Science.gov (United States)

    Adolfsson, Margareta; Johnson, Ensa; Nilsson, Stefan

    2017-05-18

    Children with cerebral palsy (CP) face particular challenges, e.g. daily pain that threaten their participation in school activities. This study focuses on how teachers, personal assistants, and clinicians in two countries with different cultural prerequisites, Sweden and South Africa, manage the pain of children in school settings. Participants' statements collected in focus groups were analysed using a directed qualitative content analysis framed by a Frequency of attendance-Intensity of involvement model, which was modified into a Knowing-Doing model. Findings indicated that pain management focused more on children's attendance in the classroom than on their involvement, and a difference between countries in terms of action-versus-reaction approaches. Swedish participants reported action strategies to prevent pain whereas South African participants primarily discussed interventions when observing a child in pain. Differences might be due to school- and healthcare systems. To provide effective support when children with CP are in pain in school settings, an action-and-reaction approach would be optimal and the use of alternative and augmentative communication strategies would help to communicate children's pain. As prevention of pain is desired, structured surveillance and treatment programs are recommended along with trustful collaboration with parents and access to "hands-on" pain management when needed. Implications for rehabilitation • When providing support, hands-on interventions should be supplemented by structured preventive programs and routines for parent collaboration (action-and-reaction approach). • When regulating support, Sweden and South Africa can learn from each other; ○ In Sweden, the implementation of a prevention program has been successful. ○ In South Africa, the possibilities giving support directly when pain in children is observed have been beneficial.

  17. Social class differences in BMI among Danish women: applying Cockerham's health lifestyles approach and Bourdieu's theory of lifestyle.

    Science.gov (United States)

    Christensen, Vibeke T; Carpiano, Richard M

    2014-07-01

    Research on social class differences in obesity and weight-related outcomes has highlighted the need to consider how such class differences reflect the unequally distributed constellations of economic, cultural, and social resources that enable and constrain health-related habits and practices or health lifestyles. Motivated by this need, the present study applies a theoretical perspective that integrates Cockerham's (2005) health lifestyles theory with Bourdieu's (1984) theoretical scholarship on social class, lifestyles, and the body to analyzing class-based differences in body mass index (BMI) among adult female respondents of a 2007 Danish national survey (n = 1376). We test hypotheses concerning how respective levels of economic, cultural, and social capital that constitute women's social class membership are associated with BMI directly and via their influence on respondent's dietary-related values, preferences, behaviors, and exercise activities. Our analyses indicate that cultural and economic capital were both directly associated with BMI. Mediation analyses revealed that greater cultural and social capital were linked to higher BMI via interest in cooking; while all three forms of capital were associated with lower BMI via greater frequency of exercise. These findings provide evidence for the many-and sometimes contradictory-ways that social class can influence body weight. Identifying such patterns can inform the design of more effective population health interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Cu-catalyzed esterification reaction via aerobic oxygenation and C-C bond cleavage: an approach to α-ketoesters.

    Science.gov (United States)

    Zhang, Chun; Feng, Peng; Jiao, Ning

    2013-10-09

    The Cu-catalyzed novel aerobic oxidative esterification reaction of 1,3-diones for the synthesis of α-ketoesters has been developed. This method combines C-C σ-bond cleavage, dioxygen activation and oxidative C-H bond functionalization, as well as provides a practical, neutral, and mild synthetic approach to α-ketoesters which are important units in many biologically active compounds and useful precursors in a variety of functional group transformations. A plausible radical process is proposed on the basis of mechanistic studies.

  19. A combinatorial chemistry approach to the investigation of cerium oxide and plutonium oxide reactions with small molecules

    Science.gov (United States)

    Brady, John T.; Warner, Benjamin P.; Bridgewater, Jon S.; Havrilla, George J.; Morris, David E.; Buscher, C. Thomas

    2000-07-01

    We are currently investigating the potential chemistry of the 3013 Standard waste storage containers. These containers are filled with waste that is a mixture of inorganic salts and plutonium oxide that has been calcined to remove water and other volatiles. There has been concern about possible pressure buildup due to the formation of hydrogen or other gases. We are utilizing a combinatorial chemistry approach to investigate a range of possible reactions that may occur in the containers with various concentrations of metal oxides and inorganic salts.

  20. Transition Metal Catalyzed Reactions of Carbohydrates: a Nonoxidative Approach to Oxygenated Organics

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Mark

    1997-01-08

    There is a critical need for new environmentally friendly processes in the United States chemical industry as legislative and economic pressures push the industry to zero-waste and cradle-to-grave responsibility for the products they produce. Carbohydrates represent a plentiful, renewable resource, which for some processes might economically replace fossil feedstocks. While the conversion of biomass to fuels, is still not generally economical, the selective synthesis of a commodity or fine chemical, however, could compete effectively if appropriate catalytic conversion systems can be found. Oxygenated organics, found in a variety of products such as nylon and polyester, are particularly attractive targets. We believe that with concerted research efforts, homogeneous transition metal catalyzed reactions could play a significant role in bringing about this future green chemistry technology.

  1. An experimental approach to angular momentum transfer in heavy ion reactions

    International Nuclear Information System (INIS)

    Babinet, R.

    1980-01-01

    The current experimental status on angular momentum transfer status in heavy ion reactions is reviewed. After a short presentation of the basic theoretical concepts that are underlying all the research works in this field, the experimental techniques that have been commonly used are presented. Results obtained by the γ-multiplicity method are discussed first. Then come, for the very heavy systems, the sequential fission data, followed by the results of a recent experiment on light charged particles. The simple theoretical concepts that are introduced first are continuously used as guidelines to discuss the following results. The respective advantages but also the basic limitations of the above three experimental techniques are exposed. Although they are expected to work best in different regions of the mass table, it is shown, that they give complementary informations which have been most useful in improving our understanding of the tangential friction mechanism

  2. Hybrid approaches for multiple-species stochastic reaction-diffusion models

    Science.gov (United States)

    Spill, Fabian; Guerrero, Pilar; Alarcon, Tomas; Maini, Philip K.; Byrne, Helen

    2015-10-01

    Reaction-diffusion models are used to describe systems in fields as diverse as physics, chemistry, ecology and biology. The fundamental quantities in such models are individual entities such as atoms and molecules, bacteria, cells or animals, which move and/or react in a stochastic manner. If the number of entities is large, accounting for each individual is inefficient, and often partial differential equation (PDE) models are used in which the stochastic behaviour of individuals is replaced by a description of the averaged, or mean behaviour of the system. In some situations the number of individuals is large in certain regions and small in others. In such cases, a stochastic model may be inefficient in one region, and a PDE model inaccurate in another. To overcome this problem, we develop a scheme which couples a stochastic reaction-diffusion system in one part of the domain with its mean field analogue, i.e. a discretised PDE model, in the other part of the domain. The interface in between the two domains occupies exactly one lattice site and is chosen such that the mean field description is still accurate there. In this way errors due to the flux between the domains are small. Our scheme can account for multiple dynamic interfaces separating multiple stochastic and deterministic domains, and the coupling between the domains conserves the total number of particles. The method preserves stochastic features such as extinction not observable in the mean field description, and is significantly faster to simulate on a computer than the pure stochastic model.

  3. Hybrid approaches for multiple-species stochastic reaction-diffusion models.

    KAUST Repository

    Spill, Fabian

    2015-10-01

    Reaction-diffusion models are used to describe systems in fields as diverse as physics, chemistry, ecology and biology. The fundamental quantities in such models are individual entities such as atoms and molecules, bacteria, cells or animals, which move and/or react in a stochastic manner. If the number of entities is large, accounting for each individual is inefficient, and often partial differential equation (PDE) models are used in which the stochastic behaviour of individuals is replaced by a description of the averaged, or mean behaviour of the system. In some situations the number of individuals is large in certain regions and small in others. In such cases, a stochastic model may be inefficient in one region, and a PDE model inaccurate in another. To overcome this problem, we develop a scheme which couples a stochastic reaction-diffusion system in one part of the domain with its mean field analogue, i.e. a discretised PDE model, in the other part of the domain. The interface in between the two domains occupies exactly one lattice site and is chosen such that the mean field description is still accurate there. In this way errors due to the flux between the domains are small. Our scheme can account for multiple dynamic interfaces separating multiple stochastic and deterministic domains, and the coupling between the domains conserves the total number of particles. The method preserves stochastic features such as extinction not observable in the mean field description, and is significantly faster to simulate on a computer than the pure stochastic model.

  4. Hybrid approaches for multiple-species stochastic reaction-diffusion models.

    KAUST Repository

    Spill, Fabian; Guerrero, Pilar; Alarcon, Tomas; Maini, Philip K; Byrne, Helen

    2015-01-01

    Reaction-diffusion models are used to describe systems in fields as diverse as physics, chemistry, ecology and biology. The fundamental quantities in such models are individual entities such as atoms and molecules, bacteria, cells or animals, which move and/or react in a stochastic manner. If the number of entities is large, accounting for each individual is inefficient, and often partial differential equation (PDE) models are used in which the stochastic behaviour of individuals is replaced by a description of the averaged, or mean behaviour of the system. In some situations the number of individuals is large in certain regions and small in others. In such cases, a stochastic model may be inefficient in one region, and a PDE model inaccurate in another. To overcome this problem, we develop a scheme which couples a stochastic reaction-diffusion system in one part of the domain with its mean field analogue, i.e. a discretised PDE model, in the other part of the domain. The interface in between the two domains occupies exactly one lattice site and is chosen such that the mean field description is still accurate there. In this way errors due to the flux between the domains are small. Our scheme can account for multiple dynamic interfaces separating multiple stochastic and deterministic domains, and the coupling between the domains conserves the total number of particles. The method preserves stochastic features such as extinction not observable in the mean field description, and is significantly faster to simulate on a computer than the pure stochastic model.

  5. Alternative approaches for econometric analysis of panel count data using dynamic latent class models (with application to doctor visits data).

    Science.gov (United States)

    Hyppolite, Judex; Trivedi, Pravin

    2012-06-01

    Cross-sectional latent class regression models, also known as switching regressions or hidden Markov models, cannot identify transitions between classes that may occur over time. This limitation can potentially be overcome when panel data are available. For such data, we develop a sequence of models that combine features of the static cross-sectional latent class (finite mixture) models with those of hidden Markov models. We model the probability of movement between categories in terms of a Markovian structure, which links the current state with a previous state, where state may refer to the category of an individual. This article presents a suite of mixture models of varying degree of complexity and flexibility for use in a panel count data setting, beginning with a baseline model which is a two-component mixture of Poisson distribution in which latent classes are fixed and permanent. Sequentially, we extend this framework (i) to allow the mixing proportions to be smoothly varying continuous functions of time-varying covariates, (ii) to add time dependence to the benchmark model by modeling the class-indicator variable as a first-order Markov chain and (iii) to extend item (i) by making it dynamic and introducing covariate dependence in the transition probabilities. We develop and implement estimation algorithms for these models and provide an empirical illustration using 1995-1999 panel data on the number of doctor visits derived from the German Socio-Economic Panel. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Fusion reaction cross-sections using the Wong model within Skyrme energy density based semiclassical extended Thomas Fermi approach

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Raj, E-mail: rajkumarfzr@gmail.com [Department of Physics, Panjab University, Chandigarh-160014 (India); School of Physics and Material Science, Thapar University, Patiala-147004 (India); Sharma, Manoj K. [School of Physics and Material Science, Thapar University, Patiala-147004 (India); Gupta, Raj K. [Department of Physics, Panjab University, Chandigarh-160014 (India)

    2011-11-15

    First, the nuclear proximity potential, obtained by using the semiclassical extended Thomas Fermi (ETF) approach in Skyrme energy density formalism (SEDF), is shown to give more realistic barriers in frozen density approximation, as compared to the sudden approximation. Then, taking advantage of the fact that, in ETF method, different Skyrme forces give different barriers (height, position and curvature), we use the l-summed extended-Wong model of Gupta and collaborators (2009) under frozen densities approximation for calculating the cross-sections, where the Skyrme force is chosen with proper barrier characteristics, not-requiring additional 'barrier modification' effects (lowering or narrowing, etc.), for a best fit to data at sub-barrier energies. The method is applied to capture cross-section data from {sup 48}Ca + {sup 238}U, {sup 244}Pu, and {sup 248}Cm reactions and to fusion-evaporation cross-sections from {sup 58}Ni + {sup 58}Ni, {sup 64}Ni + {sup 64}Ni, and {sup 64}Ni + {sup 100}Mo reactions, with effects of deformations and orientations of nuclei included, wherever required. Interestingly, whereas the capture cross-sections in Ca-induced reactions could be fitted to any force, such as SIII, SV and GSkI, by allowing a small change of couple of units in deduced l{sub max}-values at below-barrier energies, the near-barrier data point of {sup 48}Ca + {sup 248}Cm reaction could not be fitted to l{sub max}-values deduced for below-barrier energies, calling for a check of data. On the other hand, the fusion-evaporation cross-sections in Ni-induced reactions at sub-barrier energies required different Skyrme forces, representing 'modifications of the barrier', for the best fit to data at all incident center-of-mass energies E{sub c.m.}'s, displaying a kind of fusion hindrance at sub-barrier energies. This barrier modification effect is taken into care here by using different Skyrme forces for reactions belonging to different regions of

  7. Mineral Replacement Reactions as a Precursor to Strain Localisation: an (HR-)EBSD approach

    Science.gov (United States)

    Gardner, J.; Wheeler, J.; Wallis, D.; Hansen, L. N.; Mariani, E.

    2017-12-01

    Much remains to be learned about the links between metamorphism and deformation. Our work investigates the behaviour of fluid-mediated mineral replacement reaction products when exposed to subsequent shear stresses. We focus on albite from a metagabbro that has experienced metamorphism and subsequent deformation at greenschist facies, resulting in a reduction in grain size and associated strain localisation. EBSD maps show that prior to grain size reduction, product grains are highly distorted, yet they formed, and subsequently deformed, at temperatures at which extensive dislocation creep is unlikely. The Weighted Burgers Vector can be used to quantitatively describe the types of Burgers vectors present in geometrically necessary dislocation (GND) populations derived from 2-D EBSD map data. Application of this technique to the distorted product grains reveals the prominence of, among others, dislocations with apparent [010] Burgers vectors. This supports (with some caveats) the idea that dislocation creep is not responsible for the observed lattice distortion, as there are no known slip systems in plagioclase with a [010] Burgers vector. Distortion in a replacement microstructure has also been attributed to the presence of nanoscale product grains, which share very similar, but not identical, orientations due to topotactic nucleation from adjacent sites on the same substrate. As a precipitate, the product grains should be expected to be largely free of elastic strain. However, high angular resolution EBSD results demonstrate that product grains contain both elastic strains (> 10-3) and residual stresses (several hundred MPa), as well as GND densities on the order of 1014-1015 m-2. Thus we suggest the observed distortion (elastic strain plus rotations) in the lattice is produced during the mineral replacement reaction by a lattice mismatch and volume change between parent and product. Stored strain energy then provides a driving force for recovery and

  8. Hydrogen Transfer during Liquefaction of Elbistan Lignite to Biomass; Total Reaction Transformation Approach

    Science.gov (United States)

    Koyunoglu, Cemil; Karaca, Hüseyin

    2017-12-01

    Given the high cost of the tetraline solvent commonly used in liquefaction, the use of manure with EL is an important factor when considering the high cost of using tetraline as a hydrogen transfer source. In addition, due to the another cost factor which is the catalyst prices, red mud (commonly used, produced as a byproduct in the production of aluminium) is reduced cost in the work of liquefaction of coal, biomass, even coal combined biomass, corresponding that making the EL liquefaction an agenda for our country is another important factor. Conditions for liquefaction experiments conducted for hydrogen transfer from manure to coal; Catalyst concentration of 9%, liquid/solid ratio of 3/1, reaction time of 60 min, fertilizer/lignite ratio of 1/3, and the reaction temperature of 400 °C, the stirred speed of 400 rpm and the initial nitrogen pressure of 20 bar was fixed. In order to demonstrate the hydrogen, transfer from manure to coal, coal is used solely, by using tetraline (also known as a hydrogen carrier) and distilled water which is not hydrogen donor as a solvent in the co-liquefaction of experiments, and also the liquefaction conditions are carried out under an inert (N2) gas atmosphere. According to the results of the obtained liquefaction test; using tetraline solvent the total liquid product conversion percentage of the oil + gas conversion was 38.3 %, however, the results of oil+gas conversion obtained using distilled water and EL combined with manure the total liquid product conversion percentage was 7.4 %. According to the results of calorific value and elemental analysis, only the ratio of (H/C)atomic of coal obtained by using tetraline increased with the liquefaction of manure and distilled water. The reason of the increase in the amount of hydrogen due to hydrogen transfer from the manure on the solid surface of the coal, and also on the surface of the inner pore of the coal during the liquefaction, brings about the evaluation of the coal as a

  9. Modern approaches for the theoretical description of multiparticle scattering and nuclear reactions

    International Nuclear Information System (INIS)

    Kukulin, V. I.; Rubtsova, O. A.

    2012-01-01

    A review of novel approaches to solution of multiparticle scattering problems in the area above three-body breakup together with the review of new computational technologies which provide very effective and ultrafast realization of the novel approaches with ordinary PC are given. The novel direction presented here is based on two key points: a new formulation of the quantum scattering theory in a discrete Hilbert space of stationary wave packets and the massive-parallel solution of the resulted matrix equations with usage of ultrafast graphic processors (the so called GPU-computations). For the reader’s convenience, a short review of the modern GPU calculations for the medicine, physics, military applications etc. is presented.

  10. Field theoretical approach to proton-nucleus reactions: II-Multiple-step excitation process

    International Nuclear Information System (INIS)

    Eiras, A.; Kodama, T.; Nemes, M.

    1989-01-01

    A field theoretical formulation to multiple step excitation process in proton-nucleus collision within the context of a relativistic eikonal approach is presented. A closed form expression for the double differential cross section can be obtained whose structure is very simple and makes the physics transparent. Glauber's formulation of the same process is obtained as a limit of ours and the necessary approximations are studied and discussed. (author) [pt

  11. Racioethnicity, community makeup, and potential employees' reactions to organizational diversity management approaches.

    Science.gov (United States)

    Olsen, Jesse E; Martins, Luis L

    2016-05-01

    We draw on the values literature from social psychology and the acculturation literature from cross-cultural psychology to develop and test a theory of how signals about an organization's diversity management (DM) approach affect perceptions of organizational attractiveness among potential employees. We examine the mediating effects of individuals' merit-based attributions about hiring decisions at the organization, as well as the moderating effects of their racioethnicity and the racioethnic composition of their home communities. We test our theory using a within-subject policy-capturing experimental design that simulates organizational DM approaches, supplemented with census data for the participants' home communities. Results of hierarchical linear modeling (HLM) analyses suggest that the manipulated instrumental value for diversity leads to higher perceptions of organizational attractiveness, in part through heightened expectations of merit-based hiring decisions. Further, the manipulated assimilative and integrative DM approach signals are positively related to organizational attractiveness and the effect of integrative DM is strongest for racioethnic minorities from communities with especially high proportions of Whites and Whites from communities with especially low proportions of Whites. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  12. Perceived Discrimination and Emotional Reactions in People with Different Types of Disabilities: A Qualitative Approach.

    Science.gov (United States)

    Pérez-Garín, Daniel; Recio, Patricia; Magallares, Alejandro; Molero, Fernando; García-Ael, Cristina

    2018-05-15

    The purpose of this study is to assess the discourse of people with disabilities regarding their perception of discrimination and stigma. Semi-structured interviews were conducted with ten adults with physical disabilities, ten with hearing impairments and seven with visual impairments. The agreement between the coders showed an excellent reliability for all three groups, with kappa coefficients between .82 and .96. Differences were assessed between the three groups regarding the types of discrimination they experienced and their most frequent emotional responses. People with physical disabilities mainly reported being stared at, undervalued, and subtly discriminated at work, whereas people with hearing impairments mainly reported encountering barriers in leisure activities, and people with visual impairments spoke of a lack of equal opportunities, mockery and/or bullying, and overprotection. Regarding their emotional reactions, people with physical disabilities mainly reported feeling anxious and depressed, whereas people with hearing impairments reported feeling helpless, and people with visual impairments reported feeling anger and self-pity. Findings are relevant to guide future research and interventions on the stigma of disability.

  13. A New Approach and Solution Technique to Solve Time Fractional Nonlinear Reaction-Diffusion Equations

    Directory of Open Access Journals (Sweden)

    Inci Cilingir Sungu

    2015-01-01

    Full Text Available A new application of the hybrid generalized differential transform and finite difference method is proposed by solving time fractional nonlinear reaction-diffusion equations. This method is a combination of the multi-time-stepping temporal generalized differential transform and the spatial finite difference methods. The procedure first converts the time-evolutionary equations into Poisson equations which are then solved using the central difference method. The temporal differential transform method as used in the paper takes care of stability and the finite difference method on the resulting equation results in a system of diagonally dominant linear algebraic equations. The Gauss-Seidel iterative procedure then used to solve the linear system thus has assured convergence. To have optimized convergence rate, numerical experiments were done by using a combination of factors involving multi-time-stepping, spatial step size, and degree of the polynomial fit in time. It is shown that the hybrid technique is reliable, accurate, and easy to apply.

  14. Oxidation reaction of polyether-based material and its suppression in lithium rechargeable battery using 4 V class cathode, LiNi1/3Mn1/3Co1/3O2.

    Science.gov (United States)

    Kobayashi, Takeshi; Kobayashi, Yo; Tabuchi, Masato; Shono, Kumi; Ohno, Yasutaka; Mita, Yuichi; Miyashiro, Hajime

    2013-12-11

    The all solid-state lithium battery with polyether-based solid polymer electrolyte (SPE) is regarded as one of next-generation lithium batteries, and has potential for sufficient safety because of the flammable-electrolyte-free system. It has been believed that polyether-based SPE is oxidized at the polymer/electrode interface with 4 V class cathodes. Therefore, it has been used for electric devices such as organic transistor, and lithium battery under 3 V. We estimated decomposition reaction of polyether used as SPE of all solid-state lithium battery. We first identified the decomposed parts of polyether-based SPE and the conservation of most main chain framework, considering the results of SPE analysis after long cycle operations. The oxidation reaction was found to occur slightly at the ether bond in the main chain with the branched side chain. Moreover, we resolved the issue by introducing a self-sacrificing buffer layer at the interface. The introduction of sodium carboxymethyl cellulose (CMC) to the 4 V class cathode surface led to the suppression of SPE decomposition at the interface as a result of the preformation of a buffer layer from CMC, which was confirmed by the irreversible exothermic reaction during the first charge, using electrochemical calorimetry. The attained 1500 cycle operation is 1 order of magnitude longer than those of previously reported polymer systems, and compatible with those of reported commercial liquid systems. The above results indicate to proceed to an intensive research toward the realization of 4 V class "safe" lithium polymer batteries without flammable liquid electrolyte.

  15. Sum rules for the ed - NN scattering reactions and microscopic potential field-theoretical approach

    International Nuclear Information System (INIS)

    Machivariani, A.I.

    1996-01-01

    The connections between the equal-time commutators of nucleon and photon field-operators and relativistic potential approach of ed - NN scattering equations is established. Namely, it is demonstrated that: 1) equal-time commutator between nucleon field operators generated completeness condition for NN interaction functions, 2) the off-mass shell contributions in γd - NN exchange currents or in microscopic NN potential are determined by equal time commutator between nucleon field operator and photon or nucleon source operators, and 3) equal-time commutators between source operators produce sum rules for same vertex functions and effective potentials [ru

  16. A Novel Approach for Modeling Chemical Reaction in Generalized Fluid System Simulation Program

    Science.gov (United States)

    Sozen, Mehmet; Majumdar, Alok

    2002-01-01

    The Generalized Fluid System Simulation Program (GFSSP) is a computer code developed at NASA Marshall Space Flight Center for analyzing steady state and transient flow rates, pressures, temperatures, and concentrations in a complex flow network. The code, which performs system level simulation, can handle compressible and incompressible flows as well as phase change and mixture thermodynamics. Thermodynamic and thermophysical property programs, GASP, WASP and GASPAK provide the necessary data for fluids such as helium, methane, neon, nitrogen, carbon monoxide, oxygen, argon, carbon dioxide, fluorine, hydrogen, water, a hydrogen, isobutane, butane, deuterium, ethane, ethylene, hydrogen sulfide, krypton, propane, xenon, several refrigerants, nitrogen trifluoride and ammonia. The program which was developed out of need for an easy to use system level simulation tool for complex flow networks, has been used for the following purposes to name a few: Space Shuttle Main Engine (SSME) High Pressure Oxidizer Turbopump Secondary Flow Circuits, Axial Thrust Balance of the Fastrac Engine Turbopump, Pressurized Propellant Feed System for the Propulsion Test Article at Stennis Space Center, X-34 Main Propulsion System, X-33 Reaction Control System and Thermal Protection System, and International Space Station Environmental Control and Life Support System design. There has been an increasing demand for implementing a combustion simulation capability into GFSSP in order to increase its system level simulation capability of a liquid rocket propulsion system starting from the propellant tanks up to the thruster nozzle for spacecraft as well as launch vehicles. The present work was undertaken for addressing this need. The chemical equilibrium equations derived from the second law of thermodynamics and the energy conservation equation derived from the first law of thermodynamics are solved simultaneously by a Newton-Raphson method. The numerical scheme was implemented as a User

  17. An integrative approach to CTL epitope prediction: A combined algorithm integrating MHC class I binding, TAP transport efficiency, and proteasomal cleavage predictions

    DEFF Research Database (Denmark)

    Larsen, Mette Voldby; Lundegaard, Claus; Lamberth, K

    2005-01-01

    Reverse immunogenetic approaches attempt to optimize the selection of candidate epitopes, and thus minimize the experimental effort needed to identify new epitopes. When predicting cytotoxic T cell epitopes, the main focus has been on the highly specific MHC class I binding event. Methods have al.......The method is available at http://www.cbs.dtu.dk/services/NetCTL. Supplementary material is available at http://www.cbs.dtu.dk/suppl/immunology/CTL.php....

  18. Impacts of fast food and food retail environment on overweight and obesity in China: a multilevel latent class cluster approach

    NARCIS (Netherlands)

    Zhang XiaoYong, Xiaoyong; Lans, van der I.A.; Dagevos, H.

    2012-01-01

    Objective To simultaneously identify consumer segments based on individual-level consumption and community-level food retail environment data and to investigate whether the segments are associated with BMI and dietary knowledge in China. Design A multilevel latent class cluster model was applied to

  19. Stress Management in Physical Education Class: An Experiential Approach to Improve Coping Skills and Reduce Stress Perceptions in Adolescents

    Science.gov (United States)

    Lang, Christin; Feldmeth, Anna Karina; Brand, Serge; Holsboer-Trachsler, Edith; Pühse, Uwe; Gerber, Markus

    2016-01-01

    In most physical education (PE) syllabuses, promoting life skills constitutes an important educational objective. The aim of this study was to implement a coping training program (EPHECT) within regular PE and to evaluate its effects on coping and stress among vocational students. Eight classes from a vocational school were selected for study;…

  20. An assessment of the cultivated cropland class of NLCD 2006 using a multi-source and multi-criteria approach

    Science.gov (United States)

    Danielson, Patrick; Yang, Limin; Jin, Suming; Homer, Collin G.; Napton, Darrell

    2016-01-01

    We developed a method that analyzes the quality of the cultivated cropland class mapped in the USA National Land Cover Database (NLCD) 2006. The method integrates multiple geospatial datasets and a Multi Index Integrated Change Analysis (MIICA) change detection method that captures spectral changes to identify the spatial distribution and magnitude of potential commission and omission errors for the cultivated cropland class in NLCD 2006. The majority of the commission and omission errors in NLCD 2006 are in areas where cultivated cropland is not the most dominant land cover type. The errors are primarily attributed to the less accurate training dataset derived from the National Agricultural Statistics Service Cropland Data Layer dataset. In contrast, error rates are low in areas where cultivated cropland is the dominant land cover. Agreement between model-identified commission errors and independently interpreted reference data was high (79%). Agreement was low (40%) for omission error comparison. The majority of the commission errors in the NLCD 2006 cultivated crops were confused with low-intensity developed classes, while the majority of omission errors were from herbaceous and shrub classes. Some errors were caused by inaccurate land cover change from misclassification in NLCD 2001 and the subsequent land cover post-classification process.

  1. Identifying Students' Expectancy-Value Beliefs: A Latent Class Analysis Approach to Analyzing Middle School Students' Science Self-Perceptions

    Science.gov (United States)

    Phelan, Julia; Ing, Marsha; Nylund-Gibson, Karen; Brown, Richard S.

    2017-01-01

    This study extends current research by organizing information about students' expectancy-value achievement motivation, in a way that helps parents and teachers identify specific entry points to encourage and support students' science aspirations. This study uses latent class analysis to describe underlying differences in ability beliefs, task…

  2. A classical approach in simple nuclear fusion reaction 1H2+1H3 using two-dimension granular molecular dynamics model

    International Nuclear Information System (INIS)

    Viridi, S.; Kurniadi, R.; Waris, A.; Perkasa, Y. S.

    2012-01-01

    Molecular dynamics in 2-D accompanied by granular model provides an opportunity to investigate binding between nuclei particles and its properties that arises during collision in a fusion reaction. A fully classical approach is used to observe the influence of initial angle of nucleus orientation to the product yielded by the reaction. As an example, a simplest fusion reaction between 1 H 2 and 1 H 3 is observed. Several products of the fusion reaction have been obtained, even the unreported ones, including temporary 2 He 4 nucleus.

  3. PATHOPHYSIOLOGY OF POSTOPERATIVE STRESS REACTION AND MODERN APPROACHES TO NUTRITIVE SUPPORT FOR CHILDREN IN POSTOPERATIVE PERIOD

    Directory of Open Access Journals (Sweden)

    P.V. Shumilov

    2010-01-01

    Full Text Available Enteral nutrition is a method best adjusted to human physiology for correcting disorders of homeostasis in the postoperative period. Untimely and inadequate correction of these disorders may fatally affect a child’s health and rates of the child’s further development. Understanding the laws of stress response generation is important in selecting an optimal nutritive support in the postoperative period. It is necessary to take account of neuro-endocrine-immune response, changing metabolism and an impaired function of the gastrointestinal tract. Modern methods of diagnostics and treatment make it possible to resolve most of the arising issues, but it requires physicians to take a comprehensive approach and have knowledge in many areas of theoretical and practical medicine. Key words: stress, metabolism, children, enteral nutrition. (Pediatric Pharmacology. – 2010; 7(3:36-45

  4. Semi-classical approaches for the proton emission in intermediate energy heavy ion reactions

    International Nuclear Information System (INIS)

    Gregoire, C.; Scheuter, F.; Remaud, B.; Sebille, F.

    1984-05-01

    Semi-classical approaches are proposed to study the transition between the one- and two-body processes in intermediate energy heavy ion collisions. The Landau-Vlasov equation is used as a transport equation for nucleons in the nuclear matter. We apply our formalism to the fast proton ejection. On the one hand, the effects of the nucleon-nucleon collisions are studied for the particles which travel through the nucleus cores. On the other hand, the inertial emission turns out to be an important proton emission mechanism. Our results conflict the interpretation of the proton spectra in terms of moving sources. Reasonable agreements with the experimental data are found without reference to any thermal equilibrium

  5. Comparative study of postoperative stability between conventional orthognathic surgery and a surgery-first orthognathic approach after bilateral sagittal split ramus osteotomy for skeletal class III correction.

    Science.gov (United States)

    Mah, Deuk-Hyun; Kim, Su-Gwan; Oh, Ji-Su; You, Jae-Seek; Jung, Seo-Yun; Kim, Won-Gi; Yu, Kyung-Hwan

    2017-02-01

    The purpose of this study is to compare the postoperative stability of conventional orthognathic surgery to a surgery-first orthognathic approach after bilateral sagittal split ramus osteotomy (BSSRO). The study included 20 patients who underwent BSSRO for skeletal class III conventional orthognathic surgery and 20 patients who underwent a surgery-first orthognathic approach. Serial lateral cephalograms were analyzed to identify skeletal changes before surgery (T0), immediately after surgery (T1), and after surgery (T2, after 1 year or at debonding). The amount of relapse of the mandible in the conventional orthognathic surgery group from T1 to T2 was 2.23±0.92 mm ( P surgery-first orthognathic approach group from T1 to T2 was 3.49±1.71 mm ( P surgery-first orthognathic approach. Therefore, careful planning and skeletal stability should be considered in orthognathic surgery.

  6. Dependent Classes

    DEFF Research Database (Denmark)

    Gasiunas, Vaidas; Mezini, Mira; Ostermann, Klaus

    2007-01-01

    of dependent classes and a machine-checked type soundness proof in Isabelle/HOL [29], the first of this kind for a language with virtual classes and path-dependent types. [29] T.Nipkow, L.C. Poulson, and M. Wenzel. Isabelle/HOL -- A Proof Assistant for Higher-Order Logic, volume 2283 of LNCS, Springer, 2002......Virtual classes allow nested classes to be refined in subclasses. In this way nested classes can be seen as dependent abstractions of the objects of the enclosing classes. Expressing dependency via nesting, however, has two limitations: Abstractions that depend on more than one object cannot...... be modeled and a class must know all classes that depend on its objects. This paper presents dependent classes, a generalization of virtual classes that expresses similar semantics by parameterization rather than by nesting. This increases expressivity of class variations as well as the flexibility...

  7. Kinetic approach for interactive reactions of radionuclide, bacteria and granitic crushed rock

    International Nuclear Information System (INIS)

    Kim, Jung Woo; Baik, Min Hoon; Lee, Seung Yeop; Lee, Jae Kwang; Kim, Seung Soo; Oh, Jong Min; Lee, Tae Yup

    2011-01-01

    For many radionuclides, sorption is an important phenomenon as their migration rates in groundwater are reduced in both engineered barrier and fractured rock matrix. Sorption of radionuclides is strongly dependent on the chemistry of the surrounding groundwater, such as pH, Eh, ionic strength, etc., by changing their valence states (e.g.,). In addition, it is also known that some bacteria can change the mobility and speciation of a radionuclide in groundwater. Biological immobilization mechanisms of radionuclides include precipitation, transformation to less soluble forms and so on. On the other hand, bacteria can also play a role of sorbent for radionuclides. Since bacteria can not only be mobile as a colloid but also be immobile as biofilm in the rock fracture, the bacteria as the sorbents of radionuclides in the groundwater can have both positive and negative effects on the radionuclide migration. In this study, therefore, sorption of radionuclide onto rock surface in the presence of bacteria was investigated via batch experiments. Although sorption equilibrium state can be expected in the transport of weakly sorbing (distribution coefficient, K d -3 m 3 kg -1 ) or strongly adsorbing (K d > ∼4.6 m 3 kg -1 ) nuclides in fractured rock, sorption kinetics needs to be considered in the intermediate range. Therefore, the sorption of radionuclide whose valence state is expected to be changed by biological reduction was evaluated in a kinetic approach

  8. Skeletal class III malocclusion treated using a non-surgical approach supplemented with mini-implants: a case report.

    Science.gov (United States)

    Farret, Marcel Marchiori; Benitez Farret, Milton M

    2013-09-01

    We describe a 28-year-old man who sought orthodontic treatment complaining about the esthetics of his smile and difficulties associated with masticatory function. The patient had a straight facial profile, skeletal and dental class III relationship, anterior open bite and posterior crossbite. He refused orthognathic surgery and was therefore treated with camouflage orthodontics supplemented with the placement of one mini-implant in each side of the mandible to facilitate movement of the lower dentition distally, tooth-by-tooth. At the end of treatment, a class I molar relationship was obtained, with an ideal overjet and overbite and excellent intercuspation. Furthermore, the open bite and crossbite were corrected. Analysis 2 years after treatment revealed good stability of treatment outcome.

  9. About a theoretical Background of Outdoor Education in High School : A practical approach to the Integrated Classes

    OpenAIRE

    佐藤, 豊; 佐野, 裕

    2004-01-01

    This study aims to consider the educational values and prospects of outdoor education at the Integrated Classes for high school in Japan. As it should be recognized that "the cultivation of the vitality for children to live" is the most important educational target of the New Japanese Government Curriculum Guidelines. The vitality for children to live is explained as the abilities to feel nature, to collaborate with others, to take initiative, and to take own risk, for example. It should be s...

  10. Impacts of fast food and food retail environment on overweight and obesity in China: a multilevel latent class cluster approach

    OpenAIRE

    Zhang XiaoYong, Xiaoyong; Lans, van der, I.A.; Dagevos, H.

    2012-01-01

    Objective To simultaneously identify consumer segments based on individual-level consumption and community-level food retail environment data and to investigate whether the segments are associated with BMI and dietary knowledge in China. Design A multilevel latent class cluster model was applied to identify consumer segments based not only on their individual preferences for fast food, salty snack foods, and soft drinks and sugared fruit drinks, but also on the food retail environment at the ...

  11. Class II malocclusion with mutilated anterior segment: Treated with a rare approach-creating an apparent midline

    Directory of Open Access Journals (Sweden)

    Abhishek Kshetrapal

    2013-01-01

    The following case report shows a 15-year-old male patient with Class II malocclusion who had missing central incisor and canine in the upper right quadrant, which were extracted around 4 years back. The case was treated by space closure involving movement of left central incisor into right central incisor position and conversion of the left lateral incisor into left central incisor. Overall an esthetic result was achieved saving the patient from the need for a prosthesis.

  12. LMS in university for in-class education: Synergy of free software, competitive approach and social networks technology

    Science.gov (United States)

    Radygin, V. Y.; Lukyanova, N. V.; Kupriyanov, D. Yu.

    2017-01-01

    Transformation of learning management systems over last two decades was investigated. The features of using e-learning systems for in-class education were discussed. The necessity of integration e-learning system with the student performance controlling system was shown. The influence of choice of student ranking system on students' motivation was described. The own way to choice of e-learning system design principles and technologies were suggested.

  13. Facile approach to prepare pH and redox-responsive nanogels via Diels-Alder click reaction

    Directory of Open Access Journals (Sweden)

    C. M. Q. Le

    2018-08-01

    Full Text Available A novel pH and redox responsive system of sub-100 nm nanogels was prepared by arm-first approach via Diels-Alder click reaction. First, well-defined poly(ethylene glycol-block-poly(styrene-alt-maleic anhydride (PEG-b-PSM was synthesized and subsequently functionalized with furfuryl amine, leading to the formation of the dual-functional block copolymer of PEG-b-PSMf. The furfuryl groups in the PSMf block were employed to incorporate a redox-responsive linkage and the carboxylic acid moieties generated through functionalization acted as a pH-responsive part. The Diels-Alder click reaction between a bismaleimide crosslinker and PEG-b-PSMf was conducted at 60 °C, affording star-like nanogel structures. Doxorubicin, a model anticancer drug, was loaded into to the core of the nanogels primarily by the ionic interaction with carboxylates of core blocks and a highest drug loading capacity of 38.1% was obtained. Furthermore, the in vitro profile showed a low release percentage (11.2% of DOX at PBS pH 7.4, whereas a burst release (62% at pH 5.0 in the presence of 10 mM glutathione, indicating the effective pH and redox responsive characteristic of the PEG-b-PSMf nanogels.

  14. Interface-modulated approach toward multilevel metal oxide nanotubes for lithium-ion batteries and oxygen reduction reaction

    Institute of Scientific and Technical Information of China (English)

    Jiashen Meng; Chaojiang Niu; Xiong Liu; Ziang Liu; Hongliang Chen; Xuanpeng Wang; Jiantao Li

    2016-01-01

    Metal oxide hollow structures with multilevel interiors are of great interest for potential applications such as catalysis,chemical sensing,drug delivery,and energy storage.However,the controlled synthesis of multilevel nanotubes remains a great challenge.Here we develop a facile interface-modulated approach toward the synthesis of complex metal oxide multilevel nanotubes with tunable interior structures through electrospinning followed by controlled heat treatment.This versatile strategy can be effectively applied to fabricate wire-in-tube and tubein-tube nanotubes of various metal oxides.These multilevel nanotubes possess a large specific surface area,fast mass transport,good strain accommodation,and high packing density,which are advantageous for lithium-ion batteries (LIBs)and the oxygen reduction reaction (ORR).Specifically,shrinkable CoMn2O4 tube-in-tube nanotubes as a lithium-ion battery anode deliver a high discharge capacity of ~565 mAh.g-1 at a high rate of 2 A.g-1,maintaining 89% of the latter after 500 cycles.Further,as an oxygen reduction reaction catalyst,these nanotubes also exhibit excellent stability with about 92% current retention after 30,000 s,which is higher than that of commercial Pt/C (81%).Therefore,this feasible method may push the rapid development of one-dimensional (1D) nanomaterials.These multifunctional nanotubes have great potential in many frontier fields.

  15. High-throughput multiplex HLA-typing by ligase detection reaction (LDR) and universal array (UA) approach.

    Science.gov (United States)

    Consolandi, Clarissa

    2009-01-01

    One major goal of genetic research is to understand the role of genetic variation in living systems. In humans, by far the most common type of such variation involves differences in single DNA nucleotides, and is thus termed single nucleotide polymorphism (SNP). The need for improvement in throughput and reliability of traditional techniques makes it necessary to develop new technologies. Thus the past few years have witnessed an extraordinary surge of interest in DNA microarray technology. This new technology offers the first great hope for providing a systematic way to explore the genome. It permits a very rapid analysis of thousands genes for the purpose of gene discovery, sequencing, mapping, expression, and polymorphism detection. We generated a series of analytical tools to address the manufacturing, detection and data analysis components of a microarray experiment. In particular, we set up a universal array approach in combination with a PCR-LDR (polymerase chain reaction-ligation detection reaction) strategy for allele identification in the HLA gene.

  16. Approaches to Modeling Coupled Flow and Reaction in a 2-D Cementation Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Steefel, Carl; Cochepin, B.; Trotignon, L.; Bildstein, O.; Steefel, C.; Lagneau, V.; van der Lee, J.

    2008-04-01

    /precipitation. The simulation of highly non-linear reactive transport systems is also shown to be partly dependent on specific numerical approaches.

  17. Reaction of Tosylmethyl Isocyanide with N-Heteroaryl Formamidines: an Alternative Approach to the Synthesis of N-Heteroaryl Tosylimidazoles

    Energy Technology Data Exchange (ETDEWEB)

    Gomezgarcia, Omar; Salgadozamora, Hector; Reyesarellano, Aliciam; Camposaldrete, Elena; Peraltacruz, Javier [Departamento Quimica Organica, Colonia (Mexico)

    2013-09-15

    In conclusion, an alternative procedure was developed under mild conditions for the synthesis of 2-(4-tosylimidazo-1-yl)pyridines and pyrimidines by the reaction of TosMIC with the corresponding heteroaryl N,N'-dimethyl form-amidines. This approach does not involve a nucleophilic displacement of a leaving group and constitutes a further application of amidines, in which TosMIC acts as both a nucleophile and an electrophile on the heteroaryl formamidine. This process offers advantages over previously reported procedures. Tosyl methyl isocyanide (TosMIC), a multipurpose commercially available 3-unit synthon introduced by Van Leusen, reacts with a variety of groups to give heterocycles. It is important to emphasize that treatment of TosMIC with various functional groups leads to the formation of the imidazole nucleus, such as is the case with imines, imidoyl chlorides, isothiocyanates, nitrile and ethoxy methylene amino. However, only the latter group yields N-heterocycle imidazoles.

  18. THE DEVELOPMENT OF ELECTRONIC TEACHING MATERIALS BY FLIPBOOK ASSISTANCE BASED PROBLEM SOLVING SKILL WITH CTL APPROACH ON LEARNING MATHEMATICS CLASS V

    Directory of Open Access Journals (Sweden)

    RUSNILAWATI Eva Gustiana RUSNILAWATI

    2018-01-01

    Full Text Available The purpose of this research is to produce Flipbook-based Electronic Teaching Materials (BAE based on problem solving skills with CTL Approach on Vocational School Class V learning valid, practical, and effective. This type of research is development research (Development Research. This research developed Flipbook-assisted Electronic Teaching Materials (BAE on the mathematics learning of Class V Primary School by using the 4-D development model developed by Thiagarajan, Semmel, and Semmel. The validation results show that the developed Teaching Materials are worthy of use with a good minimum category. The results of the experiments show that Electronic Materials developed are practical and effective. Completed learning in the classical has reached the minimum criteria of 75% that is for problem-solving test reached 86%. Based on a questionnaire of attitudes toward mathematics, 88% of students showed an increase in attitude scores on mathematics, and 85% of students showed attitudes toward mathematics with a good minimum category.

  19. 一个形式化基于规格说明类测试的方法%An approach to formalizing specification-based class testing

    Institute of Scientific and Technical Information of China (English)

    缪淮扣; 刘玲

    2006-01-01

    This paper presents a framework that can be used to formalize the specification-based single-class test generation process.Object-Z is used to describe both software requirements and the proposed framework. Using this framework, test engineers can automatically get the testing process model during the test generation process. With this model, properties of test cases (such as relationship between test cases and methods can easily be captured. Furthermore, with the framework, the test process model can be updated automatically with the test generation process. The properties of test cases can then be updated correspondingly. It will greatly facilitate the regression testing. The main contribution of this paper is that it provides an approach to formalizing testing process by extending existing framework to class testing, and a way to represent test cases as multi-part, multi-step, multi-level artifacts.

  20. A STATISTICAL APPROACH TO RECOGNIZING SOURCE CLASSES FOR UNASSOCIATED SOURCES IN THE FIRST FERMI-LAT CATALOG

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, M. [Deutsches Elektronen Synchrotron DESY, D-15738 Zeuthen (Germany); Ajello, M.; Allafort, A.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Borgland, A. W.; Buehler, R. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Antolini, E.; Bonamente, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, I-06123 Perugia (Italy); Baldini, L.; Bellazzini, R.; Bregeon, J. [Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy); Ballet, J. [Laboratoire AIM, CEA-IRFU/CNRS/Universite Paris Diderot, Service d' Astrophysique, CEA Saclay, 91191 Gif sur Yvette (France); Barbiellini, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy); Bastieri, D. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy); Bouvier, A. [Santa Cruz Institute for Particle Physics, Department of Physics and Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95064 (United States); Brandt, T. J. [CNRS, IRAP, F-31028 Toulouse Cedex 4 (France); Brigida, M. [Dipartimento di Fisica ' M. Merlin' dell' Universita e del Politecnico di Bari, I-70126 Bari (Italy); Bruel, P., E-mail: monzani@slac.stanford.edu, E-mail: vilchez@cesr.fr, E-mail: salvetti@lambrate.inaf.it, E-mail: elizabeth.c.ferrara@nasa.gov [Laboratoire Leprince-Ringuet, Ecole polytechnique, CNRS/IN2P3, Palaiseau (France); and others

    2012-07-01

    The Fermi Large Area Telescope (LAT) First Source Catalog (1FGL) provided spatial, spectral, and temporal properties for a large number of {gamma}-ray sources using a uniform analysis method. After correlating with the most-complete catalogs of source types known to emit {gamma} rays, 630 of these sources are 'unassociated' (i.e., have no obvious counterparts at other wavelengths). Here, we employ two statistical analyses of the primary {gamma}-ray characteristics for these unassociated sources in an effort to correlate their {gamma}-ray properties with the active galactic nucleus (AGN) and pulsar populations in 1FGL. Based on the correlation results, we classify 221 AGN-like and 134 pulsar-like sources in the 1FGL unassociated sources. The results of these source 'classifications' appear to match the expected source distributions, especially at high Galactic latitudes. While useful for planning future multiwavelength follow-up observations, these analyses use limited inputs, and their predictions should not be considered equivalent to 'probable source classes' for these sources. We discuss multiwavelength results and catalog cross-correlations to date, and provide new source associations for 229 Fermi-LAT sources that had no association listed in the 1FGL catalog. By validating the source classifications against these new associations, we find that the new association matches the predicted source class in {approx}80% of the sources.

  1. Courses of helping alliance in the treatment of people with severe mental illness in Europe: a latent class analytic approach.

    Science.gov (United States)

    Loos, Sabine; Arnold, Katrin; Slade, Mike; Jordan, Harriet; Del Vecchio, Valeria; Sampogna, Gaia; Süveges, Ágnes; Nagy, Marietta; Krogsgaard Bording, Malene; Østermark Sørensen, Helle; Rössler, Wulf; Kawohl, Wolfram; Puschner, Bernd

    2015-03-01

    The helping alliance (HA) between patient and therapist has been studied in detail in psychotherapy research, but less is known about the HA in long-term community mental health care. The aim of this study was to identify typical courses of the HA and their predictors in a sample of people with severe mental illness across Europe over a measurement period of one year. Self-ratings of the HA by 588 people with severe mental illness who participated in a multicentre European study (CEDAR; ISRCTN75841675) were examined using latent class analysis. Four main patterns of alliance were identified: (1) high and stable (HS, 45.6 %), (2) high and increasing (HI, 36.9 %), (3) high and decreasing (HD, 11.3 %) and (4) low and increasing (LI, 6.1 %). Predictors of class membership were duration of illness, ethnicity, and education, receipt of state benefits, recovery, and quality of life. Results support findings from psychotherapy research about a predominantly stable course of the helping alliance in patients with severe mental illness over time. Implications for research and practice indicate to turn the attention to subgroups with noticeable courses.

  2. A STATISTICAL APPROACH TO RECOGNIZING SOURCE CLASSES FOR UNASSOCIATED SOURCES IN THE FIRST FERMI-LAT CATALOG

    International Nuclear Information System (INIS)

    Ackermann, M.; Ajello, M.; Allafort, A.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Borgland, A. W.; Buehler, R.; Antolini, E.; Bonamente, E.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bouvier, A.; Brandt, T. J.; Brigida, M.; Bruel, P.

    2012-01-01

    The Fermi Large Area Telescope (LAT) First Source Catalog (1FGL) provided spatial, spectral, and temporal properties for a large number of γ-ray sources using a uniform analysis method. After correlating with the most-complete catalogs of source types known to emit γ rays, 630 of these sources are 'unassociated' (i.e., have no obvious counterparts at other wavelengths). Here, we employ two statistical analyses of the primary γ-ray characteristics for these unassociated sources in an effort to correlate their γ-ray properties with the active galactic nucleus (AGN) and pulsar populations in 1FGL. Based on the correlation results, we classify 221 AGN-like and 134 pulsar-like sources in the 1FGL unassociated sources. The results of these source 'classifications' appear to match the expected source distributions, especially at high Galactic latitudes. While useful for planning future multiwavelength follow-up observations, these analyses use limited inputs, and their predictions should not be considered equivalent to 'probable source classes' for these sources. We discuss multiwavelength results and catalog cross-correlations to date, and provide new source associations for 229 Fermi-LAT sources that had no association listed in the 1FGL catalog. By validating the source classifications against these new associations, we find that the new association matches the predicted source class in ∼80% of the sources.

  3. On the mechanism of effective chemical reactions with turbulent mixing of reactants and finite rate of molecular reactions

    Energy Technology Data Exchange (ETDEWEB)

    Vorotilin, V. P., E-mail: VPVorotilin@yandex.ru [Russian Academy of Sciences, Institute of Applied Mechanics (Russian Federation)

    2017-01-15

    A generalization of the theory of chemical transformation processes under turbulent mixing of reactants and arbitrary values of the rate of molecular reactions is presented that was previously developed for the variant of an instantaneous reaction [13]. The use of the features of instantaneous reactions when considering the general case, namely, the introduction of the concept of effective reaction for the reactant volumes and writing a closing conservation equation for these volumes, became possible due to the partition of the whole amount of reactants into “active” and “passive” classes; the reactants of the first class are not mixed and react by the mechanism of instantaneous reactions, while the reactants of the second class approach each other only through molecular diffusion, and therefore their contribution to the reaction process can be neglected. The physical mechanism of reaction for the limit regime of an ideal mixing reactor (IMR) is revealed and described. Although formally the reaction rate in this regime depends on the concentration of passive fractions of the reactants, according to the theory presented, the true (hidden) mechanism of the reaction is associated only with the reaction of the active fractions of the reactants with vanishingly small concentration in the volume of the reactor. It is shown that the rate constant of fast chemical reactions can be evaluated when the mixing intensity of reactants is much less than that needed to reach the mixing conditions in an IMR.

  4. A new model to predict diffusive self-heating during composting incorporating the reaction engineering approach (REA) framework.

    Science.gov (United States)

    Putranto, Aditya; Chen, Xiao Dong

    2017-05-01

    During composting, self-heating may occur due to the exothermicities of the chemical and biological reactions. An accurate model for predicting maximum temperature is useful in predicting whether the phenomena would occur and to what extent it would have undergone. Elevated temperatures would lead to undesirable situations such as the release of large amount of toxic gases or sometimes would even lead to spontaneous combustion. In this paper, we report a new model for predicting the profiles of temperature, concentration of oxygen, moisture content and concentration of water vapor during composting. The model, which consists of a set of equations of conservation of heat and mass transfer as well as biological heating term, employs the reaction engineering approach (REA) framework to describe the local evaporation/condensation rate quantitatively. A good agreement between the predicted and experimental data of temperature during composting of sewage sludge is observed. The modeling indicates that the maximum temperature is achieved after some 46weeks of composting. Following this period, the temperature decreases in line with a significant decrease in moisture content and a tremendous increase in concentration of water vapor, indicating the massive cooling effect due to water evaporation. The spatial profiles indicate that the maximum temperature is approximately located at the middle-bottom of the compost piles. Towards the upper surface of the piles, the moisture content and concentration of water vapor decreases due to the moisture transfer to the surrounding. The newly proposed model can be used as reliable simulation tool to explore several geometry configurations and operating conditions for avoiding elevated temperature build-up and self-heating during industrial composting. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Simultaneous Introduction of Two Nitroxides in the Reaction: A New Approach to the Synthesis of Heterospin Complexes.

    Science.gov (United States)

    Ovcharenko, Victor; Kuznetsova, Olga; Fursova, Elena; Letyagin, Gleb; Romanenko, Galina; Bogomyakov, Artem; Zueva, Ekaterina

    2017-12-04

    A new approach to the synthesis of multispin compounds has been developed, namely, the simultaneous introduction of two different stable nitroxides (nitronyl nitroxide and imino nitroxide) in a reaction with a metal ion. An important characteristic of the new method is that nitronyl nitroxide and imino nitroxide introduced in the reaction with the metal are the products of different series; i.e., the nitronyl nitroxide molecule differs from the imino nitroxide molecule not only in one additional oxygen molecule per molecule but also in another substituent in the side chain of the organic paramagnet. This possibility was demonstrated on the synthesis of multispin compounds [Ni 2 (A 1 )(L 2 ) 2 (Piv)(MeOH)], [Ni 2 (L 1 )(A 2 ) 2 (Piv)(H 2 O)], [Co 2 (A 1 )(L 2 ) 2 (Piv)(MeOH)], and [Co 3 (L 1 ) 2 (A 2 ) 2 (Piv) 2 ], in which L n and A n differ in the substituent in the phenyl ring. The number of multispin compounds that can be synthesized by the proposed method is almost unlimited. The heterospin complexes of transition metals with coordinated nitronyl nitroxide and imino nitroxide in one molecule contain energy-different exchange interaction channels that differ in both magnitude and sign, as confirmed by the quantum-chemical analysis of exchange channels in [Ni(B 1 )(B 2 ) 2 ](NO 3 ) 2 . The series of mixed-radical complexes may include compounds with nontrivial magnetic properties such as [Co 2 (A 1 )(L 2 ) 2 (Piv)(MeOH)], which experiences bulk magnetic ordering below 3.5 K.

  6. A Novel Approach for Multi Class Fault Diagnosis in Induction Machine Based on Statistical Time Features and Random Forest Classifier

    Science.gov (United States)

    Sonje, M. Deepak; Kundu, P.; Chowdhury, A.

    2017-08-01

    Fault diagnosis and detection is the important area in health monitoring of electrical machines. This paper proposes the recently developed machine learning classifier for multi class fault diagnosis in induction machine. The classification is based on random forest (RF) algorithm. Initially, stator currents are acquired from the induction machine under various conditions. After preprocessing the currents, fourteen statistical time features are estimated for each phase of the current. These parameters are considered as inputs to the classifier. The main scope of the paper is to evaluate effectiveness of RF classifier for individual and mixed fault diagnosis in induction machine. The stator, rotor and mixed faults (stator and rotor faults) are classified using the proposed classifier. The obtained performance measures are compared with the multilayer perceptron neural network (MLPNN) classifier. The results show the much better performance measures and more accurate than MLPNN classifier. For demonstration of planned fault diagnosis algorithm, experimentally obtained results are considered to build the classifier more practical.

  7. Studying Equilibrium in the Chemical Reaction between Ferric and Iodide Ions in Solution Using a Simple and Inexpensive Approach

    Science.gov (United States)

    Nikolaychuk, Pavel Anatolyevich; Kuvaeva, Alyona Olegovna

    2016-01-01

    A laboratory experiment on the study of the chemical equilibrium based on the reaction between ferric and iodide ions in solution with the formation of ferrous ions, free iodine, and triiodide ions is developed. The total concentration of iodide and triiodide ions in the reaction mixture during the reaction is determined by the argentometric…

  8. A Microscale Approach to Chemical Kinetics in the General Chemistry Laboratory: The Potassium Iodide Hydrogen Peroxide Iodine-Clock Reaction

    Science.gov (United States)

    Sattsangi, Prem D.

    2011-01-01

    A microscale laboratory for teaching chemical kinetics utilizing the iodine clock reaction is described. Plastic pipets, 3 mL volume, are used to store and deliver precise drops of reagents and the reaction is run in a 24 well plastic tray using a total 60 drops of reagents. With this procedure, students determine the rate of reaction and the…

  9. Imagining class : A study into material social class position, subjective identification, and voting behavior across Europe

    NARCIS (Netherlands)

    D'Hooge, L.; Achterberg, P.H.J.; Reeskens, T.

    2018-01-01

    The traditional approach to class voting has largely ignored the question whether material class positions coincide with subjective class identification. Following Sosnaud et al. (2013), this study evaluates party preferences when Europeans’ material and subjective social class do not coincide.

  10. Cutting Classes

    Science.gov (United States)

    Hacker, Andrew

    1976-01-01

    Provides critical reviews of three books, "The Political Economy of Social Class", "Ethnicity: Theory and Experience," and "Ethnicity in the United States," focusing on the political economy of social class and ethnicity. (Author/AM)

  11. An exploratory study of the impact of hypermedia-based approach and science-in-fiction approach for instruction on the polymerase chain reaction

    Science.gov (United States)

    Britton, Lynda A.

    1998-12-01

    Exploration of meaningful learning of the polymerase chain reaction (PCR) followed instruction by a researcher-developed hypermedia computer program that incorporated human constructivist principles and a "science-in-fiction" chapter of a novel that described PCR. Human constructivism is the Ausubel-Novak-Gowin (1997) meaningful learning theory that supports science learning through graphic representations and multiple examples. Science-in-fiction is a new genre of fiction introduced by the prominent scientist, Carl Djerassi, to engender an appreciation for science, and its ethical dilemmas. Chapter 19 of Djerassi's 1994 novel, The Bourbaki Gambit, was placed into hypermedia format to standardize the presentation. As part of a clinical microbiology course in the medical technology curriculum at a major medical center in the Deep South, 10 undergraduates participated in this study. Each first read The Bourbaki Gambit, and then half of the participants experienced the human constructivist approach first (the PCR group) while the others first encountered the science-in-fiction approach (the Chapter 19 group). For the rest, the order of presentation was reversed, so that all experienced both programs. Students' explanations while using the computer were videotaped. Students were tested and interviewed before experiencing either program, after their first instructional session, and again after the second instructional session. These students were also assessed on their knowledge of the nature of science by taking the Nature of Science Questionnaire, before and after instruction (Roach, 1993) and interviewed as a cross-check on its reliability. Students' preferred learning approaches were determined using Schmeck's Inventory of Learning Processes (Schmeck, Ribich, & Ramanaiah, 1977). Data were collected and analyzed both qualitatively and quantitatively using appropriate verbal analysis techniques (Chi, 1997). All but three students reached a structural level of PCR

  12. The Effects of a Flipped Classroom Approach on Class Engagement and Skill Performance in a Blackboard Course

    Science.gov (United States)

    Elmaadaway, Mohamed Ali Nagy

    2018-01-01

    This paper reports on a study that investigated whether a flipped classroom approach enhanced perceptions of levels of engagement and skill performance among students enrolled in a Blackboard course at a Saudi university. Fifty-eight participants were divided into control and experimental groups, which were taught using a traditional and a flipped…

  13. Extension of a Kinetic Approach to Chemical Reactions to Electronic Energy Levels and Reactions Involving Charged Species with Application to DSMC Simulations

    Science.gov (United States)

    Liechty, Derek S.

    2014-01-01

    The ability to compute rarefied, ionized hypersonic flows is becoming more important as missions such as Earth reentry, landing high mass payloads on Mars, and the exploration of the outer planets and their satellites are being considered. Recently introduced molecular-level chemistry models that predict equilibrium and nonequilibrium reaction rates using only kinetic theory and fundamental molecular properties are extended in the current work to include electronic energy level transitions and reactions involving charged particles. These extensions are shown to agree favorably with reported transition and reaction rates from the literature for near-equilibrium conditions. Also, the extensions are applied to the second flight of the Project FIRE flight experiment at 1634 seconds with a Knudsen number of 0.001 at an altitude of 76.4 km. In order to accomplish this, NASA's direct simulation Monte Carlo code DAC was rewritten to include the ability to simulate charge-neutral ionized flows, take advantage of the recently introduced chemistry model, and to include the extensions presented in this work. The 1634 second data point was chosen for comparisons to be made in order to include a CFD solution. The Knudsen number at this point in time is such that the DSMC simulations are still tractable and the CFD computations are at the edge of what is considered valid because, although near-transitional, the flow is still considered to be continuum. It is shown that the inclusion of electronic energy levels in the DSMC simulation is necessary for flows of this nature and is required for comparison to the CFD solution. The flow field solutions are also post-processed by the nonequilibrium radiation code HARA to compute the radiative portion.

  14. Extension of a Kinetic Approach to Chemical Reactions to Electronic Energy Levels and Reactions Involving Charged Species With Application to DSMC Simulations

    Science.gov (United States)

    Liechty, Derek S.

    2013-01-01

    The ability to compute rarefied, ionized hypersonic flows is becoming more important as missions such as Earth reentry, landing high mass payloads on Mars, and the exploration of the outer planets and their satellites are being considered. Recently introduced molecular-level chemistry models that predict equilibrium and nonequilibrium reaction rates using only kinetic theory and fundamental molecular properties are extended in the current work to include electronic energy level transitions and reactions involving charged particles. These extensions are shown to agree favorably with reported transition and reaction rates from the literature for nearequilibrium conditions. Also, the extensions are applied to the second flight of the Project FIRE flight experiment at 1634 seconds with a Knudsen number of 0.001 at an altitude of 76.4 km. In order to accomplish this, NASA's direct simulation Monte Carlo code DAC was rewritten to include the ability to simulate charge-neutral ionized flows, take advantage of the recently introduced chemistry model, and to include the extensions presented in this work. The 1634 second data point was chosen for comparisons to be made in order to include a CFD solution. The Knudsen number at this point in time is such that the DSMC simulations are still tractable and the CFD computations are at the edge of what is considered valid because, although near-transitional, the flow is still considered to be continuum. It is shown that the inclusion of electronic energy levels in the DSMC simulation is necessary for flows of this nature and is required for comparison to the CFD solution. The flow field solutions are also post-processed by the nonequilibrium radiation code HARA to compute the radiative portion of the heating and is then compared to the total heating measured in flight.

  15. Event-based state estimation for a class of complex networks with time-varying delays: A comparison principle approach

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wenbing [Department of Mathematics, Yangzhou University, Yangzhou 225002 (China); Wang, Zidong [Department of Computer Science, Brunel University London, Uxbridge, Middlesex, UB8 3PH (United Kingdom); Liu, Yurong, E-mail: yrliu@yzu.edu.cn [Department of Mathematics, Yangzhou University, Yangzhou 225002 (China); Communication Systems and Networks (CSN) Research Group, Faculty of Engineering, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Ding, Derui [Shanghai Key Lab of Modern Optical System, Department of Control Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093 (China); Alsaadi, Fuad E. [Communication Systems and Networks (CSN) Research Group, Faculty of Engineering, King Abdulaziz University, Jeddah 21589 (Saudi Arabia)

    2017-01-05

    The paper is concerned with the state estimation problem for a class of time-delayed complex networks with event-triggering communication protocol. A novel event generator function, which is dependent not only on the measurement output but also on a predefined positive constant, is proposed with hope to reduce the communication burden. A new concept of exponentially ultimate boundedness is provided to quantify the estimation performance. By means of the comparison principle, some sufficient conditions are obtained to guarantee that the estimation error is exponentially ultimately bounded, and then the estimator gains are obtained in terms of the solution of certain matrix inequalities. Furthermore, a rigorous proof is proposed to show that the designed triggering condition is free of the Zeno behavior. Finally, a numerical example is given to illustrate the effectiveness of the proposed event-based estimator. - Highlights: • An event-triggered estimator is designed for complex networks with time-varying delays. • A novel event generator function is proposed to reduce the communication burden. • The comparison principle is utilized to derive the sufficient conditions. • The designed triggering condition is shown to be free of the Zeno behavior.

  16. Automatic identification approach for high-performance liquid chromatography-multiple reaction monitoring fatty acid global profiling.

    Science.gov (United States)

    Tie, Cai; Hu, Ting; Jia, Zhi-Xin; Zhang, Jin-Lan

    2015-08-18

    Fatty acids (FAs) are a group of lipid molecules that are essential to organisms. As potential biomarkers for different diseases, FAs have attracted increasing attention from both biological researchers and the pharmaceutical industry. A sensitive and accurate method for globally profiling and identifying FAs is required for biomarker discovery. The high selectivity and sensitivity of high-performance liquid chromatography-multiple reaction monitoring (HPLC-MRM) gives it great potential to fulfill the need to identify FAs from complicated matrices. This paper developed a new approach for global FA profiling and identification for HPLC-MRM FA data mining. Mathematical models for identifying FAs were simulated using the isotope-induced retention time (RT) shift (IRS) and peak area ratios between parallel isotope peaks for a series of FA standards. The FA structures were predicated using another model based on the RT and molecular weight. Fully automated FA identification software was coded using the Qt platform based on these mathematical models. Different samples were used to verify the software. A high identification efficiency (greater than 75%) was observed when 96 FA species were identified in plasma. This FAs identification strategy promises to accelerate FA research and applications.

  17. A quantitative real time polymerase chain reaction approach for estimating processed animal proteins in feed: preliminary data

    Directory of Open Access Journals (Sweden)

    Maria Cesarina Abete

    2013-04-01

    Full Text Available Lifting of the ban on the use of processed animal proteins (PAPs from non-ruminants in non-ruminant feed is in the wind, avoiding intraspecies recycling. Discrimination of species will be performed through polymerase chain reaction (PCR, which is at a moment a merely qualitative method. Nevertheless, quantification of PAPs in feed is needed. The aim of this study was to approach the quantitative determination of PAPs in feed through Real Time (RT-PCR technique; three different protocols picked up from the literature were tested. Three different kind of matrices were examined: pure animal meals (bovine, chicken and pork; one feed sample certified by the European reference laboratory on animal proteins (EURL AP in feed spiked with 0.1% bovine meal; and genomic DNAs from bovine, chicken and pork muscles. The limit of detection (LOD of the three protocols was set up. All the results obtained from the three protocols considered failed in the quantification process, most likely due to the uncertain copy numbers of the analytical targets chosen. This preliminary study will allow us to address further investigations, with the purpose of developing a RT-PCR quantitative method.

  18. An effective rate equation approach to reaction kinetics in small volumes: theory and application to biochemical reactions in nonequilibrium steady-state conditions.

    Science.gov (United States)

    Grima, R

    2010-07-21

    Chemical master equations provide a mathematical description of stochastic reaction kinetics in well-mixed conditions. They are a valid description over length scales that are larger than the reactive mean free path and thus describe kinetics in compartments of mesoscopic and macroscopic dimensions. The trajectories of the stochastic chemical processes described by the master equation can be ensemble-averaged to obtain the average number density of chemical species, i.e., the true concentration, at any spatial scale of interest. For macroscopic volumes, the true concentration is very well approximated by the solution of the corresponding deterministic and macroscopic rate equations, i.e., the macroscopic concentration. However, this equivalence breaks down for mesoscopic volumes. These deviations are particularly significant for open systems and cannot be calculated via the Fokker-Planck or linear-noise approximations of the master equation. We utilize the system-size expansion including terms of the order of Omega(-1/2) to derive a set of differential equations whose solution approximates the true concentration as given by the master equation. These equations are valid in any open or closed chemical reaction network and at both the mesoscopic and macroscopic scales. In the limit of large volumes, the effective mesoscopic rate equations become precisely equal to the conventional macroscopic rate equations. We compare the three formalisms of effective mesoscopic rate equations, conventional rate equations, and chemical master equations by applying them to several biochemical reaction systems (homodimeric and heterodimeric protein-protein interactions, series of sequential enzyme reactions, and positive feedback loops) in nonequilibrium steady-state conditions. In all cases, we find that the effective mesoscopic rate equations can predict very well the true concentration of a chemical species. This provides a useful method by which one can quickly determine the

  19. Learner differences and learning outcomes in an introductory biochemistry class: attitude toward images, visual cognitive skills, and learning approach.

    Science.gov (United States)

    Milner, Rachel E

    2014-01-01

    The practice of using images in teaching is widespread, and in science education images are used so extensively that some have argued they are now the "main vehicle of communication" (C. Ferreira, A. Arroio Problems Educ. 21st Century 2009, 16, 48-53). Although this phenomenon is especially notable in the field of biochemistry, we know little about the role and importance of images in communicating concepts to students in the classroom. This study reports the development of a scale to assess students' attitude toward biochemical images, particularly their willingness and ability to use the images to support their learning. In addition, because it is argued that images are central in the communication of biochemical concepts, we investigated three "learner differences" which might impact learning outcomes in this kind of classroom environment: attitude toward images, visual cognitive skills, and learning approach. Overall, the students reported a positive attitude toward the images, the majority agreeing that they liked images and considered them useful. However, the participants also reported that verbal explanations were more important than images in helping them to understand the concepts. In keeping with this we found that there was no relationship between learning outcomes and the students' self-reported attitude toward images or visual cognitive skills. In contrast, learning outcomes were significantly correlated with the students' self-reported approach to learning. These findings suggest that images are not necessarily the main vehicle of communication in a biochemistry classroom and that verbal explanations and encouragement of a deep learning approach are important considerations in improving our pedagogical approach. © 2013 International Union of Biochemistry and Molecular Biology, Inc.

  20. Culture and social class.

    Science.gov (United States)

    Miyamoto, Yuri

    2017-12-01

    A large body of research in Western cultures has demonstrated the psychological and health effects of social class. This review outlines a cultural psychological approach to social stratification by comparing psychological and health manifestations of social class across Western and East Asian cultures. These comparisons suggest that cultural meaning systems shape how people make meaning and respond to material/structural conditions associated with social class, thereby leading to culturally divergent manifestations of social class. Specifically, unlike their counterparts in Western cultures, individuals of high social class in East Asian cultures tend to show high conformity and other-orientated psychological attributes. In addition, cultures differ in how social class impacts health (i.e. on which bases, through which pathways, and to what extent). Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Development of Instructional Materials for Electrochemical Module Class XII Science High School Students with Guided Inquiry Learning Approach

    Directory of Open Access Journals (Sweden)

    Lilik Fatmawati

    2014-06-01

    Full Text Available Pengembangan Bahan Ajar Modul Elektrokimia untuk Siswa SMA Kelas XII IPA dengan Pendekatan Pembelajaran Inkuiri Terbimbing Abstract: The aim of this study was to determine the feasibility and effectiveness of the electrochemical module for high school students of class XII results of development. Electrochemical module of the development consists of two learning activities, ie to the material Volta cells and electrolysis cells for the material. Results of the assessment by two chemistry lecturer, State University of Malang and two chemistry teachers XII as an expert content / learning material for eligibility contents was 92.9%, for eligibility and completeness of presentation is 91.1%, and for the eligibility of language is 92.3% , which is classified as very feasible criteria. Overall the average value was 92.1 feasibility. Effectiveness module is indicated by the results of the development of perception and student learning outcomes. Students' perceptions obtained from student assessment results to module development. In the limited field trials obtained average value is 81.8 for all aspects of the maximum value of 100. Obtaining the average value of student learning outcomes for the cognitive aspect is 83.3, for the affective aspect is 82.3, and for the psychomotor aspect is 83.8 out of 100. The maximum value of the overall results of the study showed that the electrochemical module for high school students Class XII Science development results are very decent and very effectively used in the learning process. Key Words: guided inquiry, electrochemical module, model 4-D Abstrak: Tujuan penelitian ini adalah mengetahui kelayakan, dan keefektifan modul elektrokimia untuk siswa SMA kelas XII hasil pengembangan. Modul Elektrokimia hasil pengembangan terdiri dari dua kegiatan belajar, yaitu untuk materi sel Volta dan untuk materi sel elektrolisis. Hasil penilaian oleh dua dosen kimia Universitas Negeri Malang dan dua guru kimia kelas XII sebagai

  2. An Innovative Approach to Balancing Chemical-Reaction Equations: A Simplified Matrix-Inversion Technique for Determining The Matrix Null Space

    OpenAIRE

    Thorne, Lawrence R.

    2011-01-01

    I propose a novel approach to balancing equations that is applicable to all chemical-reaction equations; it is readily accessible to students via scientific calculators and basic computer spreadsheets that have a matrix-inversion application. The new approach utilizes the familiar matrix-inversion operation in an unfamiliar and innovative way; its purpose is not to identify undetermined coefficients as usual, but, instead, to compute a matrix null space (or matrix kernel). The null space then...

  3. A kinetic-theory approach for computing chemical-reaction rates in upper-atmosphere hypersonic flows.

    Science.gov (United States)

    Gallis, Michael A; Bond, Ryan B; Torczynski, John R

    2009-09-28

    Recently proposed molecular-level chemistry models that predict equilibrium and nonequilibrium reaction rates using only kinetic theory and fundamental molecular properties (i.e., no macroscopic reaction-rate information) are investigated for chemical reactions occurring in upper-atmosphere hypersonic flows. The new models are in good agreement with the measured Arrhenius rates for near-equilibrium conditions and with both measured rates and other theoretical models for far-from-equilibrium conditions. Additionally, the new models are applied to representative combustion and ionization reactions and are in good agreement with available measurements and theoretical models. Thus, molecular-level chemistry modeling provides an accurate method for predicting equilibrium and nonequilibrium chemical-reaction rates in gases.

  4. Chemical kinetics of gas reactions

    CERN Document Server

    Kondrat'Ev, V N

    2013-01-01

    Chemical Kinetics of Gas Reactions explores the advances in gas kinetics and thermal, photochemical, electrical discharge, and radiation chemical reactions. This book is composed of 10 chapters, and begins with the presentation of general kinetic rules for simple and complex chemical reactions. The next chapters deal with the experimental methods for evaluating chemical reaction mechanisms and some theories of elementary chemical processes. These topics are followed by discussions on certain class of chemical reactions, including unimolecular, bimolecular, and termolecular reactions. The rema

  5. Reciprocity theory of homogeneous reactions

    Science.gov (United States)

    Agbormbai, Adolf A.

    1990-03-01

    The reciprocity formalism is applied to the homogeneous gaseous reactions in which the structure of the participating molecules changes upon collision with one another, resulting in a change in the composition of the gas. The approach is applied to various classes of dissociation, recombination, rearrangement, ionizing, and photochemical reactions. It is shown that for the principle of reciprocity to be satisfied it is necessary that all chemical reactions exist in complementary pairs which consist of the forward and backward reactions. The backward reaction may be described by either the reverse or inverse process. The forward and backward processes must satisfy the same reciprocity equation. Because the number of dynamical variables is usually unbalanced on both sides of a chemical equation, it is necessary that this balance be established by including as many of the dynamical variables as needed before the reciprocity equation can be formulated. Statistical transformation models of the reactions are formulated. The models are classified under the titles free exchange, restricted exchange and simplified restricted exchange. The special equations for the forward and backward processes are obtained. The models are consistent with the H theorem and Le Chatelier's principle. The models are also formulated in the context of the direct simulation Monte Carlo method.

  6. Microscopic approach of molecular dynamics. Applications to reactions near the barrier; Approches microscopiques de la dynamique nucleaire. Applications aux reactions autour de la barriere

    Energy Technology Data Exchange (ETDEWEB)

    Simenel, C.; Avez, B. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee (DSM/DAPNIA/SPhN), 91- Gif sur Yvette (France); Lacroix, D. [GANIL, 14 - Caen (France)

    2007-07-01

    This lecture introduces several microscopic approaches to nuclear dynamics. Our goal is to provide a good description of low energy heavy ions collisions. We study both the formalism and the practical application of the time-dependent Hartree-Fock (TDHF) theory. The TDHF approach gives a mean field dynamics of the system under the assumption of independent particles. As an example, we study the fusion of both spherical and deformed nuclei with TDHF. We also show that nucleon transfer may occur between nuclei below the barrier. These studies allow us to specify the field of applications of TDHF in one hand, and, in the other hand, its intrinsic limitations, as for instance the fact that there is no fusion by tunnel effect with TDHF. It is then important to get rid of the independent particle assumption. We finally present some approaches to go beyond TDHF, including for instance pairing and/or collision term between nucleons, though only few realistic applications have been performed so far. (authors)

  7. Study of a class of photovoltaic systems using a bond graph approach. Modeling, analysis and control; Etude d'une classe de systemes photovoltaiques par une approche bond graph. Modelisation, analyse et commande

    Energy Technology Data Exchange (ETDEWEB)

    Andoulsi, R.

    2001-12-01

    We present in this thesis a study of a class of photovoltaic system by a bond graph approach. This study concerns the modelling, the analysis and the control of some configurations including PV generator, DC/DC converters and DC motor-pumps. The modelling of the different elements of a photovoltaic system is an indispensable stage that must precede all application of sizing, identification or simulation. However, theses PV systems are of hybrid type and their modelling is complex. It is why we use a unified modelling approach based on the bond graph technique. This methodology is completely systematic and has a sufficient flexibility for allowing the introduction of different components in the system. In the first chapter, we recall the principle of functioning of a photovoltaic generator and we treat mainly the MPPT (Maximum Power Point Tracking) working. In the second chapter, we elaborate bond graph models of various photovoltaic system configurations. For the PV source, we elaborate, in a first stage, a complete model taking into account the various physical phenomena influencing the quality of the PV source. In a second stage, we deduce a reduced bond graph model more easy to use for analysis and control purposes. For the DC/DC converters, we recall the bond graph modelling of switching elements and the average bond graph of the DC/DC converters developed in the literature. Thus, we deduce the bond graphs models of the various DC/DC converters to be used. The third chapter presents a dynamic study of some configurations stability in linear procedure. In the fourth chapter, we study the feasibility of non linear controllers by input/output linearization for some configurations of PV systems. In this study, we use the concept of inverse bond graph to determine, by a bond graph approach, the expression of the control input and the nature of the stability of the internal dynamics (dynamics of zeros). The fifth chapter is dedicated for the presentation of some

  8. Reaction of Topopah Spring tuff with J-13 water: a geochemical modeling approach using the EQ3/6 reaction path code

    Energy Technology Data Exchange (ETDEWEB)

    Delany, J.M.

    1985-11-25

    EQ3/6 geochemical modeling code package was used to investigate the interaction of the Topopah Spring Tuff and J-13 water at high temperatures. EQ3/6 input parameters were obtained from the results of laboratory experiments using USW G-1 core and J-13 water. Laboratory experiments were run at 150 and 250{sup 0}C for 66 days using both wafer-size and crushed tuff. EQ3/6 modeling reproduced results of the 150{sup 0}C experiments except for a small increase in the concentration of potassium that occurs in the first few days of the experiments. At 250{sup 0}C, the EQ3/6 modeling reproduced the major water/rock reactions except for a small increase in potassium, similar to that noted above, and an overall increase in aluminum. The increase in potassium concentration cannot be explained at this time, but the increase in A1 concentration is believed to be caused by the lack of thermodynamic data in the EQ3/6 data base for dachiardite, a zeolite observed as a run product at 250{sup 0}C. The ability to reproduce the majority of the experimental rock/water interactions at 150{sup 0}C validates the use of EQ3/6 as a geochemical modeling tool that can be used to theoretically investigate physical/chemical environments in support of the Waste Package Task of NNWSI.

  9. Reaction of Topopah Spring tuff with J-13 water: a geochemical modeling approach using the EQ3/6 reaction path code

    International Nuclear Information System (INIS)

    Delany, J.M.

    1985-01-01

    EQ3/6 geochemical modeling code package was used to investigate the interaction of the Topopah Spring Tuff and J-13 water at high temperatures. EQ3/6 input parameters were obtained from the results of laboratory experiments using USW G-1 core and J-13 water. Laboratory experiments were run at 150 and 250 0 C for 66 days using both wafer-size and crushed tuff. EQ3/6 modeling reproduced results of the 150 0 C experiments except for a small increase in the concentration of potassium that occurs in the first few days of the experiments. At 250 0 C, the EQ3/6 modeling reproduced the major water/rock reactions except for a small increase in potassium, similar to that noted above, and an overall increase in aluminum. The increase in potassium concentration cannot be explained at this time, but the increase in A1 concentration is believed to be caused by the lack of thermodynamic data in the EQ3/6 data base for dachiardite, a zeolite observed as a run product at 250 0 C. The ability to reproduce the majority of the experimental rock/water interactions at 150 0 C validates the use of EQ3/6 as a geochemical modeling tool that can be used to theoretically investigate physical/chemical environments in support of the Waste Package Task of NNWSI

  10. Evaluation of POE and instructor-led problem-solving approaches integrated into force and motion lecture classes using a model analysis technique

    International Nuclear Information System (INIS)

    Rakkapao, S; Pengpan, T; Srikeaw, S; Prasitpong, S

    2014-01-01

    This study aims to investigate the use of the predict–observe–explain (POE) approach integrated into large lecture classes on forces and motion. It is compared to the instructor-led problem-solving method using model analysis. The samples are science (SC, N = 420) and engineering (EN, N = 434) freshmen, from Prince of Songkla University, Thailand. Research findings from the force and motion conceptual evaluation indicate that the multimedia-supported POE method promotes students’ learning better than the problem-solving method, in particular for the velocity and acceleration concepts. There is a small shift of the students’ model states after the problem-solving instruction. Moreover, by using model analysis instructors are able to investigate students’ misconceptions and evaluate teaching methods. It benefits instructors in organizing subsequent instructional materials. (paper)

  11. Tandem Aldol-Michael Reactions in Aqueous Diethylamine Medium: A Greener and Efficient Approach to Bis-Pyrimidine Derivatives

    Directory of Open Access Journals (Sweden)

    Abdullah M. Al-Majid

    2013-12-01

    Full Text Available A simple protocol, involving the green synthesis for the construction of novel bis-pyrimidine derivatives, 3a–i and 4a–e are accomplished by the aqueous diethylamine media promoted tandem Aldol-Michael reaction between two molecules of barbituric acid derivatives 1a,b with various aldehydes. This efficient synthetic protocol using an economic and environmentally friendly reaction media with versatility and shorter reaction time provides bis-pyrimidine derivatives with high yields (88%–99%.

  12. Selecting measures to prevent deleterious alkali-silica reaction in concrete : rationale for the AASHTO PP65 prescriptive approach.

    Science.gov (United States)

    2012-10-01

    PP65-11 provides two approaches for selecting preventive measures: (i) a performance approach based on laboratory testing, and (ii) a prescriptive approach based on a consideration of the reactivity of the aggregate, type and size of structure, expos...

  13. Splitting Schemes & Segregation In Reaction-(Cross-)Diffusion Systems

    OpenAIRE

    Carrillo, José A.; Fagioli, Simone; Santambrogio, Filippo; Schmidtchen, Markus

    2017-01-01

    One of the most fascinating phenomena observed in reaction-diffusion systems is the emergence of segregated solutions, i.e. population densities with disjoint supports. We analyse such a reaction cross-diffusion system. In order to prove existence of weak solutions for a wide class of initial data without restriction about their supports or their positivity, we propose a variational splitting scheme combining ODEs with methods from optimal transport. In addition, this approach allows us to pr...

  14. Intramolecular Diels-Alder Reactions in Organic Synthesis

    OpenAIRE

    Sizemore, Nicholas Blandford Luke

    2014-01-01

    Intramolecular Diels-Alder (IMDA) reactions are an important class of reactions in synthetic organic chemistry for the rapid construction of polycyclic frameworks. Three classes of IMDA reactions were investigated synthetically and computationally: 1) all-carbon type 1 IMDA reactions, 2) N-acylnitroso type 2 IMDA reactions, and 3) cyano-azadiene IMDA reactions. The first class was implemented in research toward the total synthesis of maoecrystal Z and isopalhinine A. The second class was stud...

  15. Electrochemically induced reactions in soils - a new approach to the in-situ remediation of contaminated soils?

    Energy Technology Data Exchange (ETDEWEB)

    Rahner, D.; Ludwig, G.; Roehrs, J. [Dresden Univ. of Technology, Inst. of Physical Chemistry and Electrochemistry (Germany); Neumann, V.; Nitsche, C.; Guderitz, I. [Soil and Groundwater Lab. GmbH, Dresden (Germany)

    2001-07-01

    Electrochemical reactions can be induced in soils if the soil matrix contains particles or films with electronic conducting properties ('microconductors'). In these cases the wet soil may act as a 'diluted' electrochemical solid bed reactor. A discussion of this reaction principle within the soil matrix will be presented here. It will be shown, that under certain conditions immobile organic contaminants may be converted. (orig.)

  16. A straightforward approach towards combined α-amino and α-hydroxy acids based on Passerini reactions

    Directory of Open Access Journals (Sweden)

    Ameer F. Zahoor

    2011-09-01

    Full Text Available Complex amino acids with an α-acyloxycarbonyl functionality in the side chain are easily available through epoxide opening by chelated enolates and subsequent oxidation/Passerini reaction. This protocol works with both, aldehyde and ketone intermediates, as long as the ketones are activated by electron-withdrawing groups. In principle Ugi reactions are also possible, allowing the generation of diamino acid derivatives.

  17. Production of 149Tb in deep inelastic transfer reactions: an approach to the angular momentum of fragments

    International Nuclear Information System (INIS)

    Rivet, M.F.; Bimbot, R.; Gardes, D.; Fleury, A.; Hubert, F.; Llabador, Y.

    1978-01-01

    The excitation functions for deep inelastic reactions in which two to six charges are transferred from 40 Ar and 63 Cu ions to rare earth targets have been measured using activation techniques, the observed radionuclides being 150 Dy, 151 Dy and 149 gTb. From the comparison of the curves relative to 149 gTb and those relative to 150 Dy, 151 Dy, it was deduced that the low spin isomer 149 gTb was produced with significant probability for low incident energies. Using data from (heavy ions, xn) reactions, it was possible to attribute this production to the deexcitation of Tb fragments formed in deep inelastic transfers with angular momenta lower than 9n. This result is in good agreement with the angular momentum calculations performed under the hypothesis that the initial angular momentum window leading to deep inelastic reactions is situated between the critical angular momentum for fusion and that corresponding to grazing collisions. As far as Cu induced reactions are concerned, both hypothesis of rolling and sticking are consistent with the experimental data. For Ar induced reactions, the results indicate that the stage of sticking is not reached when the incident energy is lower than 200 MeV

  18. Word classes

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2007-01-01

    in grammatical descriptions of some 50 languages, which together constitute a representative sample of the world’s languages (Hengeveld et al. 2004: 529). It appears that there are both quantitative and qualitative differences between word class systems of individual languages. Whereas some languages employ...... a parts-of-speech system that includes the categories Verb, Noun, Adjective and Adverb, other languages may use only a subset of these four lexical categories. Furthermore, quite a few languages have a major word class whose members cannot be classified in terms of the categories Verb – Noun – Adjective...... – Adverb, because they have properties that are strongly associated with at least two of these four traditional word classes (e.g. Adjective and Adverb). Finally, this article discusses some of the ways in which word class distinctions interact with other grammatical domains, such as syntax and morphology....

  19. Calculation of total free energy yield as an alternative approach for predicting the importance of potential chemolithotrophic reactions in geothermal springs.

    Science.gov (United States)

    Dodsworth, Jeremy A; McDonald, Austin I; Hedlund, Brian P

    2012-08-01

    To inform hypotheses regarding the relative importance of chemolithotrophic metabolisms in geothermal environments, we calculated free energy yields of 26 chemical reactions potentially supporting chemolithotrophy in two US Great Basin hot springs, taking into account the effects of changing reactant and product activities on the Gibbs free energy as each reaction progressed. Results ranged from 1.2 × 10(-5) to 3.6 J kg(-1) spring water, or 3.7 × 10(-5) to 11.5 J s(-1) based on measured flow rates, with aerobic oxidation of CH(4) or NH4 + giving the highest average yields. Energy yields calculated without constraining pH were similar to those at constant pH except for reactions where H(+) was consumed, which often had significantly lower yields when pH was unconstrained. In contrast to the commonly used normalization of reaction chemical affinities per mole of electrons transferred, reaction energy yields for a given oxidant varied by several orders of magnitude and were more sensitive to differences in the activities of products and reactants. The high energy yield of aerobic ammonia oxidation is consistent with previous observations of significant ammonia oxidation rates and abundant ammonia-oxidizing archaea in sediments of these springs. This approach offers an additional lens through which to view the thermodynamic landscape of geothermal springs. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  20. Scaling analysis in modeling transport and reaction processes a systematic approach to model building and the art of approximation

    CERN Document Server

    Krantz, William B

    2007-01-01

    This book is unique as the first effort to expound on the subject of systematic scaling analysis. Not written for a specific discipline, the book targets any reader interested in transport phenomena and reaction processes. The book is logically divided into chapters on the use of systematic scaling analysis in fluid dynamics, heat transfer, mass transfer, and reaction processes. An integrating chapter is included that considers more complex problems involving combined transport phenomena. Each chapter includes several problems that are explained in considerable detail. These are followed by several worked examples for which the general outline for the scaling is given. Each chapter also includes many practice problems. This book is based on recognizing the value of systematic scaling analysis as a pedagogical method for teaching transport and reaction processes and as a research tool for developing and solving models and in designing experiments. Thus, the book can serve as both a textbook and a reference boo...

  1. High-throughput screening for various classes of doping agents using a new 'dilute-and-shoot' liquid chromatography-tandem mass spectrometry multi-target approach.

    Science.gov (United States)

    Guddat, S; Solymos, E; Orlovius, A; Thomas, A; Sigmund, G; Geyer, H; Thevis, M; Schänzer, W

    2011-01-01

    A new multi-target approach based on liquid chromatography--electrospray ionization tandem mass spectrometry (LC-(ESI)-MS/MS) is presented to screen for various classes of prohibited substances using direct injection of urine specimens. With a highly sensitive new generation hybrid mass spectrometer classic groups of drugs--for example, diuretics, beta2-agonists--stimulants and narcotics are detectable at concentration levels far below the required limits. Additionally, more challenging and various new target compounds could be implemented. Model compounds of stimulant conjugates were studied to investigate a possible screening without complex sample preparation. As a main achievement, the integration of the plasma volume expanders dextran and hydroxyethyl starch (HES), commonly analyzed in time-consuming, stand-alone procedures, is accomplished. To screen for relatively new prohibited compounds, a common metabolite of the selective androgen receptor modulator (SARMs) andarine, a metabolite of growth hormone releasing peptide (GHRP-2), and 5-amino-4-imidazolecarboxyamide ribonucleoside (AICAR) are analyzed. Following a completely new approach, conjugates of di(2-ethylhexyl) phthalate (DEHP) metabolites are monitored to detect abnormally high levels of plasticizers indicating for illicit blood transfusion. The assay was fully validated for qualitative purposes considering the parameters specificity, intra- (3.2-16.6%) and inter-day precision (0.4-19.9%) at low, medium and high concentration, robustness, limit of detection (1-70 ng/ml, dextran: 30 µg/ml, HES: 10 µg/ml) and ion suppression/enhancement effects. The analyses of post-administration and routine doping control samples demonstrates the applicability of the method for sports drug testing. This straightforward and reliable approach accomplishes the combination of different screening procedures resulting in a high-throughput method that increases the efficiency of the labs daily work. Copyright © 2011 John

  2. Class size versus class composition

    DEFF Research Database (Denmark)

    Jones, Sam

    Raising schooling quality in low-income countries is a pressing challenge. Substantial research has considered the impact of cutting class sizes on skills acquisition. Considerably less attention has been given to the extent to which peer effects, which refer to class composition, also may affect...... bias from omitted variables, the preferred IV results indicate considerable negative effects due to larger class sizes and larger numbers of overage-for-grade peers. The latter, driven by the highly prevalent practices of grade repetition and academic redshirting, should be considered an important...

  3. Modified two-body potential approach to the peripheral direct capture astrophysical a+A->B+γ reaction and asymptotic normalization coefficients

    International Nuclear Information System (INIS)

    Igamov, S.B.; Yarmukhamedov, R.

    2007-01-01

    A modified two-body potential approach is proposed for determination of both the asymptotic normalization coefficient (ANC) (or the respective nuclear vertex constant (NVC)) for the A+a->B (for the virtual decay B->A+a) from an analysis of the experimental S-factor for the peripheral direct capture a+A->B+γ reaction and the astrophysical S-factor, S(E), at low experimentally inaccessible energy regions. The approach proposed involves two additional conditions which verify the peripheral character of the considered reaction and expresses S(E) in terms of the ANC. The connection between NVC (ANC) and the effective range parameters for Aa-scattering is derived. To test this approach we reanalyse the precise experimental astrophysical S-factors for t+α->Li7+γ reaction at energies E= Li7(g.s.), α+t->Li7(0.478 MeV) and of S(E) at E=<50 keV. These ANC values have been used for getting information about the ''indirect'' measured values of the effective range parameters and the p-wave phase shift for αt-scattering in the energy range of 100-bar E-bar 180 keV

  4. A simple approach to the solvent reorganisation Gibbs free energy in electron transfer reactions of redox metalloproteins

    DEFF Research Database (Denmark)

    Ulstrup, Jens

    1999-01-01

    We discuss a simple model for the environmental reorganisation Gibbs free energy, E-r, in electron transfer between a metalloprotein and a small reaction partner. The protein is represented as a dielectric globule with low dielectric constant, the metal centres as conducting spheres, all embedded...

  5. Interaction of 2'-deoxyguanosine with cis-2-butene-1,4-dial: Computational approach to analysis of multistep chemical reactions

    Directory of Open Access Journals (Sweden)

    Sviatenko L. K.

    2014-05-01

    Full Text Available cis-2-Butene-1,4-dial represents a microsomal metabolite of furan, an industrially important chemical found in cigarette smoke, air pollution, and also in canned or jarred food. It is expected to be a human carcinogen. Aim. Investigation an effect of cis-2-butene-1,4-dial on the 2'-deoxyguanine which is a model of DNA site. Methods. Optimization of reaction species molecular structures, spectral parameters and Gibbs free energy calculations were performed using Gaussian09 program. Systems of differential equations for kinetics generation were solved using Mathcad15 program. Results. The predicted mechanism of the reaction of cis-2-butene-1,4-dial with 2'-deoxyguanine consists of four-step process formation of four diastereomeric primary adducts and further base-mediated five-step transformation of the primary adducts to the secondary one. The reaction kinetics, which allows defining theconcentration change of any reaction species was calculated. Conclusions. Under physiological conditions the interaction between cis-2-butene-1,4-dial and 2'-deoxyguanine leads to the formation of a stable adduct which could be responsible for the furan genotoxicity.

  6. Getting a line on commercial advertising : a bio-informational approach to study pleasure and arousal reactions to ads

    NARCIS (Netherlands)

    Poels, K.; Dewitte, S.

    2008-01-01

    The bio-informational theory of emotion contends that pleasure and arousal reactions are organized around two universal motivational systems: an appetitive and a defensive motivational system. This paper posits that the appetitive motivation, reflected by a tight linear relation between pleasure and

  7. A variational approach to bifurcation points of a reaction-diffusion system with obstacles and neumann boundary conditions

    Czech Academy of Sciences Publication Activity Database

    Eisner, Jan; Kučera, Milan; Väth, Martin

    2016-01-01

    Roč. 61, č. 1 (2016), s. 1-25 ISSN 0862-7940 R&D Projects: GA ČR GA13-12580S Institutional support: RVO:67985904 ; RVO:67985840 Keywords : reaction-diffusion system * unlateral condition * variational inequality Subject RIV: EG - Zoology; BA - General Mathematics (MU-W) Impact factor: 0.618, year: 2016

  8. Pure visual imagery as a potential approach to achieve three classes of control for implementation of BCI in non-motor disorders

    Science.gov (United States)

    Sousa, Teresa; Amaral, Carlos; Andrade, João; Pires, Gabriel; Nunes, Urbano J.; Castelo-Branco, Miguel

    2017-08-01

    Objective. The achievement of multiple instances of control with the same type of mental strategy represents a way to improve flexibility of brain-computer interface (BCI) systems. Here we test the hypothesis that pure visual motion imagery of an external actuator can be used as a tool to achieve three classes of electroencephalographic (EEG) based control, which might be useful in attention disorders. Approach. We hypothesize that different numbers of imagined motion alternations lead to distinctive signals, as predicted by distinct motion patterns. Accordingly, a distinct number of alternating sensory/perceptual signals would lead to distinct neural responses as previously demonstrated using functional magnetic resonance imaging (fMRI). We anticipate that differential modulations should also be observed in the EEG domain. EEG recordings were obtained from twelve participants using three imagery tasks: imagery of a static dot, imagery of a dot with two opposing motions in the vertical axis (two motion directions) and imagery of a dot with four opposing motions in vertical or horizontal axes (four directions). The data were analysed offline. Main results. An increase of alpha-band power was found in frontal and central channels as a result of visual motion imagery tasks when compared with static dot imagery, in contrast with the expected posterior alpha decreases found during simple visual stimulation. The successful classification and discrimination between the three imagery tasks confirmed that three different classes of control based on visual motion imagery can be achieved. The classification approach was based on a support vector machine (SVM) and on the alpha-band relative spectral power of a small group of six frontal and central channels. Patterns of alpha activity, as captured by single-trial SVM closely reflected imagery properties, in particular the number of imagined motion alternations. Significance. We found a new mental task based on visual motion

  9. Mapeamento digital de classes de solos: características da abordagem brasileira Digital soil mapping: characteristics of the brazilian approach

    Directory of Open Access Journals (Sweden)

    Alexandre ten Caten

    2012-11-01

    necessary to discuss the main characteristics of those studies related to the automated mapping of soil classes, which will enable a broader perspective of the subject and guide future works and demands. The mapping of soil classes using DSM techniques is recent in the country, the first publication in this topic occurred just in 2006. Among the predictive functions the predominant is logistic regression. The soil formation factor relief was used in all studies reviewed. Quality of predictive models was evaluated employing error matrix and kappa which were the most common procedures. The consolidation of this automated approach as an auxiliary tool to the conventional soil mapping will demand training of young soil scientists to use geoinformation technologies and quantitative tools to handle aspects of soil variability.

  10. Social Classes

    DEFF Research Database (Denmark)

    Aktor, Mikael

    2018-01-01

    . Although this social structure was ideal in nature and not equally confirmed in other genres of ancient and medieval literature, it has nevertheless had an immense impact on Indian society. The chapter presents an overview of the system with its three privileged classes, the Brahmins, the Kṣatriyas......The notions of class (varṇa) and caste (jāti) run through the dharmaśāstra literature (i.e. Hindu Law Books) on all levels. They regulate marriage, economic transactions, work, punishment, penance, entitlement to rituals, identity markers like the sacred thread, and social interaction in general...

  11. The Use of Invisalign® System in the Management of the Orthodontic Treatment before and after Class III Surgical Approach.

    Science.gov (United States)

    Pagani, Renato; Signorino, Fabrizio; Poli, Pier Paolo; Manzini, Pietro; Panisi, Irene

    2016-01-01

    The approach to skeletal dysmorphisms in the maxillofacial area usually requires an orthodontic treatment by means of fixed appliances, both before and after the surgical phase. Since its introduction, Invisalign system has become a popular treatment choice for the clinicians because of the aesthetics and comfort of the removable clear aligners compared with the traditional appliances. Therefore, the aim of the present report was to illustrate the management of a malocclusion by means of Invisalign system associated with the traditional surgical technique. The present paper shows a case of a 23-year-old male patient characterized by a Class III malocclusion with lateral deviation of the mandible to the left side and cross-bite on teeth 2.2, 2.3, and 2.4. Invisalign system was used during the pre- and postsurgical phases rather than fixed appliances. The posttreatment cephalometric analysis emphasized the stability of the dental and skeletal symmetry corrections, occlusion and functional balance, over a 6-year follow-up. The results achieved at the end of the treatment showed how Invisalign can be effective in the management of the orthodontic phases in orthognathic surgery. The follow-up after 6 years emphasizes the stability of the treatment over time.

  12. The Use of Invisalign® System in the Management of the Orthodontic Treatment before and after Class III Surgical Approach

    Directory of Open Access Journals (Sweden)

    Renato Pagani

    2016-01-01

    Full Text Available The approach to skeletal dysmorphisms in the maxillofacial area usually requires an orthodontic treatment by means of fixed appliances, both before and after the surgical phase. Since its introduction, Invisalign system has become a popular treatment choice for the clinicians because of the aesthetics and comfort of the removable clear aligners compared with the traditional appliances. Therefore, the aim of the present report was to illustrate the management of a malocclusion by means of Invisalign system associated with the traditional surgical technique. The present paper shows a case of a 23-year-old male patient characterized by a Class III malocclusion with lateral deviation of the mandible to the left side and cross-bite on teeth 2.2, 2.3, and 2.4. Invisalign system was used during the pre- and postsurgical phases rather than fixed appliances. The posttreatment cephalometric analysis emphasized the stability of the dental and skeletal symmetry corrections, occlusion and functional balance, over a 6-year follow-up. The results achieved at the end of the treatment showed how Invisalign can be effective in the management of the orthodontic phases in orthognathic surgery. The follow-up after 6 years emphasizes the stability of the treatment over time.

  13. Enzymatic conversion of sucrose to glucose and its anomerization by quantitative NMR spectroscopy: Application of a simple consecutive reaction rates approach

    Science.gov (United States)

    Singh, Jaideep; Her, Cheenou; Krishnan, V. V.

    2018-02-01

    The anomerization of carbohydrates is an essential process that determines the relative stabilization of stereoisomers in an aqueous solution. In a typical real-time enzyme kinetics experiment, the substrate (sucrose) is converted to glucose and fructose by the enzyme invertase. The product (α-D-glucose) starts to convert to β-D-glucose immediately by hydrolysis. Though the anomerization process is independent of the enzyme catalysis, the progress curve describing the production of β-D-glucose from α-D-glucose is directly affected by the kinetics of consecutive reactions. When α-D-glucose is continually converted to β-D-glucose, by the enzymatic action, the time course of both α- and β-D-glucose is influenced by the enzyme kinetics. Thus, a reversible first-order rate equation is not adequate to model the reaction mechanism, leading to erroneous results on the rates of formation of the glucose anomers. In this manuscript, we incorporate an approximate method to address consecutive general reactions involving enzyme kinetics and first-order reaction processes. The utility of the approach is demonstrated in the real-time NMR measurement of the anomerization process of α-D-glucose (enzymatically produced from sucrose) to β-D-glucose, as a function of invertase enzyme concentration. Variable temperature experiments were used to estimate the thermodynamic parameters of the anomerization process and are consistent with literature values.

  14. Birthing Classes

    Science.gov (United States)

    ... management options. Breastfeeding basics. Caring for baby at home. Birthing classes are not just for new parents, though. ... midwife. Postpartum care. Caring for your baby at home, including baby first aid. Lamaze One of the most popular birthing techniques in the U.S., Lamaze has been around ...

  15. Abordagem clínica não-cirúrgica no tratamento da má oclusão de Classe III Non-surgical approaches to Class III malocclusions treatment

    Directory of Open Access Journals (Sweden)

    Eustáquio A. Araújo

    2008-12-01

    Full Text Available A abordagem clínica não-cirúrgica da Classe III coloca-se entre os grandes desafios da Ortodontia e vem, desde sempre, gerando controvérsia entre clínicos e pesquisadores. Alguns defendem a tese de que o crescimento e o desenvolvimento do complexo craniofacial são determinados geneticamente e, portanto, inalteráveis. Para esses, a correção da grande maioria de casos de Classe III passará por intervenções orto-cirúrgicas, devendo a terapia ser realizada assim que cessar o período mais ativo do crescimento. Por outro lado, há aqueles que, mesmo concordando com o peso da hereditariedade na etiologia da Classe III, acreditam ser possível modificar o padrão e a direção do crescimento e, através de uma abordagem não-cirúrgica, minimizar a má oclusão ou até mesmo tratá-la com sucesso. Em face da controvérsia, quais seriam as possibilidades ortodônticas? Inúmeros são os relatos de que uma intervenção adequada, em momento adequado, acompanhada de um estudo do padrão familiar, pode, muitas vezes, minimizar o desenvolvimento de uma Classe III. Procedimentos selecionados com critério podem reduzir a indicação de intervenções cirúrgicas e proporcionar resultados positivos e duradouros. Há evidências clínicas e científicas de que algumas decisões terapêuticas podem mudar o curso de muitos prognósticos sombrios.Orthodontic management of the Class III malocclusion has been a constant challenge to the orthodontic profession and remains a controversial issue among clinicians and researches. Some support the belief that growth and size of the craniofacial complex are genetically predetermined and cannot be changed. They assume that the great majority of Class III cases are "untreatable" and that they are due to surgical intervention after growth has been completed. Even agreeing that heredity plays a major role in this type os deviation, others support the contention that the pattern and direction of growth can be

  16. Approach to photocatalysis at the molecular level. Design of photocatalysts, detection of intermediate species, and reaction mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Anpo, Masakazu [Department of Applied Chemistry, University of Osaka Prefecture, Gakuen-cho, Sakai, Osaka (Japan)

    1995-08-01

    The characterization of the Cu{sup +}/ZSM-5 catalysts prepared via reduction of ion-exchanged Cu{sup 2+}/ZSM-5 samples and highly dispersed Ti-oxide catalysts anchored on Vycor glass has been undertaken by in-situ photoluminescence, EPR, XAFS (XANES and FT-EXAFS), and FT-IR spectroscopy. UV-irradiation of the Cu{sup +}/ZSM-5 catalyst in the presence of NO leads to the direct photocatalytic decomposition of NO into N{sub 2} and O{sub 2} at normal temperatures. UV-irradiation of the highly dispersed anchored Ti-oxide catalyst in the presence of CO{sub 2} and H{sub 2}O also leads to the evolution of CH{sub 4}, CO, and CH{sub 3}OH at normal temperatures. The clarification of the coordination structure of the active surface sites and the direct detection of the reaction precursors and intermediate species in these photocatalytic systems contributed significantly in characterizing the molecular scale reaction mechanisms. Based on these results, the design of highly concentrated and efficient photocatalysts has successfully been achieved by application of the sol-gel method

  17. Silver mirror reaction as an approach to construct a durable, robust superhydrophobic surface of bamboo timber with high conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Chunde; Li, Jingpeng [School of Engineering, Zhejiang Agricultural and Forestry University, Lin’an 311300 (China); Key Laboratory of Wood Science and Technology, Zhejiang Province (China); Han, Shenjie; Wang, Jin; Yao, Qiufang [School of Engineering, Zhejiang Agricultural and Forestry University, Lin’an 311300 (China); Sun, Qingfeng, E-mail: zafuqfsun@163.com [School of Engineering, Zhejiang Agricultural and Forestry University, Lin’an 311300 (China); Key Laboratory of Wood Science and Technology, Zhejiang Province (China)

    2015-06-25

    Highlights: • Ag NPs were deposited onto the surface of bamboo timber by silver mirror reaction. • The Ag NPs made the intrinsic insulating bamboo timber have a high conductivity. • The modified surfaces displayed superhydrophobicity even for corrosive solutions. - Abstract: Silver nanoparticles (Ag NPs) were successfully in situ deposited onto the surface of the bamboo timber through a simple silver mirror reaction. Scanning electron microscopy (SEM) images showed that the surface of the bamboo timber was densely covered with the uniform Ag NPs, which made the intrinsic insulating bamboo timber conductive. With further modification by fluoroalkylsilane (FAS), the Ag NPs-covered bamboo timber showed superhydrophobicity with the water contact angle (WCA) of 155°. Simultaneously, the modified bamboo timber displayed a durable and robust superhydrophobic property even under corrosive solutions including acidic, alkali and NaCl solutions with different molar concentrations. Especially in harsh conditions of boiling water or intense water stirring, the modified bamboo timber remained superhydrophobicity and high conductivity.

  18. Process spectroscopy in microemulsions—setup and multi-spectral approach for reaction monitoring of a homogeneous hydroformylation process

    Science.gov (United States)

    Meyer, K.; Ruiken, J.-P.; Illner, M.; Paul, A.; Müller, D.; Esche, E.; Wozny, G.; Maiwald, M.

    2017-03-01

    Reaction monitoring in disperse systems, such as emulsions, is of significant technical importance in various disciplines like biotechnological engineering, chemical industry, food science, and a growing number other technical fields. These systems pose several challenges when it comes to process analytics, such as heterogeneity of mixtures, changes in optical behavior, and low optical activity. Concerning this, online nuclear magnetic resonance (NMR) spectroscopy is a powerful technique for process monitoring in complex reaction mixtures due to its unique direct comparison abilities, while at the same time being non-invasive and independent of optical properties of the sample. In this study the applicability of online-spectroscopic methods on the homogeneously catalyzed hydroformylation system of 1-dodecene to tridecanal is investigated, which is operated in a mini-plant scale at Technische Universität Berlin. The design of a laboratory setup for process-like calibration experiments is presented, including a 500 MHz online NMR spectrometer, a benchtop NMR device with 43 MHz proton frequency as well as two Raman probes and a flow cell assembly for an ultraviolet and visible light (UV/VIS) spectrometer. Results of high-resolution online NMR spectroscopy are shown and technical as well as process-specific problems observed during the measurements are discussed.

  19. Coding Class

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine; Hansbøl, Mikala

    Denne rapport rummer evaluering og dokumentation af Coding Class projektet1. Coding Class projektet blev igangsat i skoleåret 2016/2017 af IT-Branchen i samarbejde med en række medlemsvirksomheder, Københavns kommune, Vejle Kommune, Styrelsen for IT- og Læring (STIL) og den frivillige forening...... Coding Pirates2. Rapporten er forfattet af Docent i digitale læringsressourcer og forskningskoordinator for forsknings- og udviklingsmiljøet Digitalisering i Skolen (DiS), Mikala Hansbøl, fra Institut for Skole og Læring ved Professionshøjskolen Metropol; og Lektor i læringsteknologi, interaktionsdesign......, design tænkning og design-pædagogik, Stine Ejsing-Duun fra Forskningslab: It og Læringsdesign (ILD-LAB) ved Institut for kommunikation og psykologi, Aalborg Universitet i København. Vi har fulgt og gennemført evaluering og dokumentation af Coding Class projektet i perioden november 2016 til maj 2017...

  20. Comparison of surgical and non-surgical orthodontic treatment approaches on occlusal and cephalometric outcomes in patients with Class II Division I malocclusions

    Directory of Open Access Journals (Sweden)

    Sheila Daniels

    2017-07-01

    Full Text Available Abstract Background This study aimed to examine end-of-treatment outcomes of severe Class II Division I malocclusion patients treated with surgical or non-surgical approaches. This study tests the hypotheses that occlusal outcomes (ABO-OGS and cephalometric outcomes differ between these groups. Methods A total of 60 patients were included: 20 of which underwent surgical correction and 40 of which did not. Cast grading of initial and final study models was performed and information was gathered from pre- to post-treatment cephalometric radiographs. The end-of-treatment ABO-OGS and cephalometric outcomes were compared to Mann-Whitney U tests and multivariable linear regression models. Results Following adjustment for multiple confounders (age, gender, complexity of case, and skeletal patterns, the final deband score (ABO-OGS was similar for both groups (23.8 for surgical group versus 22.5 for non-surgical group. Those treated surgically had a significantly larger reduction in ANB angle, 3.4° reduction versus 1.5° reduction in the non-surgical group (p = 0.002. The surgical group also showed increased maxillary incisor proclination (p = 0.001 compared to the non-surgical group. This might be attributed to retroclination of maxillary incisors during treatment selection in the non-surgical group—namely, extraction of premolars to mask the discrepancy. Conclusions Those treated surgically had a significantly larger reduction in ANB angle and increased maxillary incisor proclination compared to those treated non-surgically with no significant changes in occlusal outcomes.

  1. Development of the work function approach to the underpotential deposition of metals. Application to the hydrogen evolution reaction

    International Nuclear Information System (INIS)

    Trasatti, S.

    1975-01-01

    A theory is developed for the underpotential deposition of metals. Concepts are then extended to oxygen and hydrogen adsorption. Analysis of results shows that, unlike oxygen adsorption, hydrogen adsorption in solution probably follows a different pattern with respect to the gas phase situation. The hydrogen evolution reaction is discussed in the light of the above findings and it is shown that usual concepts regarding the reactivity scale of metals towards hydrogen should be reconsidered taking into account solvent and entropy effects. The latters can account for the behaviour of sp-metals. The formers are important with transition metals. The final picture is consistent with the idea that M-H 2 O interactions are much stronger on transition than on sp-metals. (orig.) [de

  2. Screening of Riboflavin-Producing Lactobacilli by a Polymerase-Chain-Reaction-Based Approach and Microbiological Assay.

    Science.gov (United States)

    Thakur, Kiran; Tomar, Sudhir Kumar; Brahma, Biswajit; De, Sachinandan

    2016-03-09

    Riboflavin has an important role in various cellular metabolic activities through its participation in oxidation-reduction reactions. In this study, as many as 60 lactobacilli were screened for the presence or absence of riboflavin biosynthesis genes and riboflavin production. Of these, only 14 strains were able to grow in a commercial riboflavin-free medium. We observed that the presence of riboflavin biosynthesis genes is strain-specific across different species of lactobacilli. The microbiological assay was found to be appreciably reproducible, sensitive, rapid, and inexpensive and, hence, can be employed for screening the riboflavin-producing strains. The study thus represents a convenient and efficient method for selection of novel riboflavin producers. These riboflavin(+) strains thus identified and characterized could be explored as potent candidates for the development of a wide range of dairy- and cereal-based foods for the delivery of in situ riboflavin to consumers.

  3. Combined experimental and theoretical approach to understand the reactivity of a mononuclear Cu(II)-hydroperoxo complex in oxygenation reactions.

    Science.gov (United States)

    Kamachi, Takashi; Lee, Yong-Min; Nishimi, Tomonori; Cho, Jaeheung; Yoshizawa, Kazunari; Nam, Wonwoo

    2008-12-18

    A copper(II) complex bearing a pentadentate ligand, [Cu(II)(N4Py)(CF(3)SO(3))(2)] (1) (N4Py = N,N-bis(2-pyridylmethyl)bis(2-pyridyl)methylamine), was synthesized and characterized with various spectroscopic techniques and X-ray crystallography. A mononuclear Cu(II)-hydroperoxo complex, [Cu(II)(N4Py)(OOH)](+) (2), was then generated in the reaction of 1 and H(2)O(2) in the presence of base, and the reactivity of the intermediate was investigated in the oxidation of various substrates at -40 degrees C. In the reactivity studies, 2 showed a low oxidizing power such that 2 reacted only with triethylphosphine but not with other substrates such as thioanisole, benzyl alcohol, 1,4-cyclohexadiene, cyclohexene, and cyclohexane. In theoretical work, we have conducted density functional theory (DFT) calculations on the epoxidation of ethylene by 2 and a [Cu(III)(N4Py)(O)](+) intermediate (3) at the B3LYP level. The activation barrier is calculated to be 39.7 and 26.3 kcal/mol for distal and proximal oxygen attacks by 2, respectively. This result indicates that the direct ethylene epoxidation by 2 is not a plausible pathway, as we have observed in the experimental work. In contrast, the ethylene epoxidation by 3 is a downhill and low-barrier process. We also found that 2 cannot be a precursor to 3, since the homolytic cleavage of the O-O bond of 2 is very endothermic (i.e., 42 kcal/mol). On the basis of the experimental and theoretical results, we conclude that a mononuclear Cu(II)-hydroperoxo species bearing a pentadentate N5 ligand is a sluggish oxidant in oxygenation reactions.

  4. Listvenite formation from peridotite: Insights from Oman Drilling Project hole BT1B and preliminary reaction path model approach.

    Science.gov (United States)

    de Obeso, J. C.; Kelemen, P. B.; Manning, C. E.; Michibayashi, K.; Harris, M.

    2017-12-01

    Oman Drilling Project hole BT1B drilled 300 meters through the basal thrust of the Samail ophiolite. The first 200 meters of this hole are dominated by listvenites (completely carbonated peridotites) and serpentinites. Below 200 meters the hole is mainly composed of metasediments and metavolcanics. This core provides a unique record of interaction between (a) mantle peridotite in the leading edge of the mantle wedge and (b) hydrous, CO2 rich fluids derived from subducting lithologies similar to those in the metamorphic sole. We used EQ3/6 to simulate a reaction path in which hydrous fluid in equilibrium with qtz + calcite + feldspar + chlorite or smectite reacts with initially fresh peridotite at 100°C (the estimated temperature of alteration, Falk & Kelemen GCA 2015) and 5 kb. Water was first equilibrated with minerals observed during core description in the metamorphic sole at 100°C and 5kb. This fluid is then reacted with olivine enstatite and diopside (Mg#90) approximating the average composition of residual mantle peridotite (harzburgite) in Oman. Secondary minerals resulting from complete reaction are then reacted again with the initial fluid in an iterative process, up to water/rock > 1000. Water/rock close to 1 results in complete serpentinization of the peridotite, with chrysotile, brucite and magnetite as the only minerals. Water/rock >10 produces carbonates, chlorite and talc. Further increasing water/rock to > 100 produces assemblages dominated by carbonates and quartz with minor muscovite, similar to listvenites of hole BT1B that contain qtz + carbonates + Fe-oxyhydroxides + relict spinel ± chromian muscovite and fuchsite. The results of this preliminary model are consistent with the complex veining history of core from BT1B, with carbonate/iron oxide veins in both listvenites and serpentinites interpreted to be the earliest record of peridotite carbonation after initial serpentinization.

  5. Open Experimentation on Phenomena of Chemical Reactions via the Learning Company Approach in Early Secondary Chemistry Education

    Science.gov (United States)

    Beck, Katharina; Witteck, Torsten; Eilks, Ingo

    2010-01-01

    Presented is a case study on the implementation of open and inquiry-type experimentation in early German secondary chemistry education. The teaching strategy discussed follows the learning company approach. Originally adopted from vocational education, the learning company method is used to redirect lab-oriented classroom practice towards a more…

  6. Design of a New Concentration Series for the Orthogonal Sample Design Approach and Estimation of the Number of Reactions in Chemical Systems.

    Science.gov (United States)

    Shi, Jiajia; Liu, Yuhai; Guo, Ran; Li, Xiaopei; He, Anqi; Gao, Yunlong; Wei, Yongju; Liu, Cuige; Zhao, Ying; Xu, Yizhuang; Noda, Isao; Wu, Jinguang

    2015-11-01

    A new concentration series is proposed for the construction of a two-dimensional (2D) synchronous spectrum for orthogonal sample design analysis to probe intermolecular interaction between solutes dissolved in the same solutions. The obtained 2D synchronous spectrum possesses the following two properties: (1) cross peaks in the 2D synchronous spectra can be used to reflect intermolecular interaction reliably, since interference portions that have nothing to do with intermolecular interaction are completely removed, and (2) the two-dimensional synchronous spectrum produced can effectively avoid accidental collinearity. Hence, the correct number of nonzero eigenvalues can be obtained so that the number of chemical reactions can be estimated. In a real chemical system, noise present in one-dimensional spectra may also produce nonzero eigenvalues. To get the correct number of chemical reactions, we classified nonzero eigenvalues into significant nonzero eigenvalues and insignificant nonzero eigenvalues. Significant nonzero eigenvalues can be identified by inspecting the pattern of the corresponding eigenvector with help of the Durbin-Watson statistic. As a result, the correct number of chemical reactions can be obtained from significant nonzero eigenvalues. This approach provides a solid basis to obtain insight into subtle spectral variations caused by intermolecular interaction.

  7. Global minimum profile error (GMPE) - a least-squares-based approach for extracting macroscopic rate coefficients for complex gas-phase chemical reactions.

    Science.gov (United States)

    Duong, Minh V; Nguyen, Hieu T; Mai, Tam V-T; Huynh, Lam K

    2018-01-03

    Master equation/Rice-Ramsperger-Kassel-Marcus (ME/RRKM) has shown to be a powerful framework for modeling kinetic and dynamic behaviors of a complex gas-phase chemical system on a complicated multiple-species and multiple-channel potential energy surface (PES) for a wide range of temperatures and pressures. Derived from the ME time-resolved species profiles, the macroscopic or phenomenological rate coefficients are essential for many reaction engineering applications including those in combustion and atmospheric chemistry. Therefore, in this study, a least-squares-based approach named Global Minimum Profile Error (GMPE) was proposed and implemented in the MultiSpecies-MultiChannel (MSMC) code (Int. J. Chem. Kinet., 2015, 47, 564) to extract macroscopic rate coefficients for such a complicated system. The capability and limitations of the new approach were discussed in several well-defined test cases.

  8. Nernst-Planck Based Description of Transport, Coulombic Interactions and Geochemical Reactions in Porous Media: Modeling Approach and Benchmark Experiments

    DEFF Research Database (Denmark)

    Rolle, Massimo; Sprocati, Riccardo; Masi, Matteo

    2018-01-01

    ‐ but also under advection‐dominated flow regimes. To accurately describe charge effects in flow‐through systems, we propose a multidimensional modeling approach based on the Nernst‐Planck formulation of diffusive/dispersive fluxes. The approach is implemented with a COMSOL‐PhreeqcRM coupling allowing us......, and high‐resolution experimental datasets. The latter include flow‐through experiments that have been carried out in this study to explore the effects of electrostatic interactions in fully three‐dimensional setups. The results of the simulations show excellent agreement for all the benchmarks problems...... the quantification and visualization of the specific contributions to the diffusive/dispersive Nernst‐Planck fluxes, including the Fickian component, the term arising from the activity coefficient gradients, and the contribution due to electromigration....

  9. An intranuclear cascade-percolation approach for protons and light fragments production in neon-niobium reactions at 400 and 800 MeV per nucleon

    International Nuclear Information System (INIS)

    Montarou, G.; Marroncle, J.; Alard, J.P.; Augerat, J.; Bastid, N.; Charmensat, P.; Dupieux, P.; Fraysse, L.; Parizet, M.J.; Rahmani, A.; Brochard, F.; Gorodetzky, P.; Racca, C.; Cugnon, J.

    1992-01-01

    The results of intranuclear cascade calculations (ideal gas with two body collisions and no mean-field), complemented by a simple percolation procedure, are compared with experimental data on protons and light nuclear fragments (d, t, 3 He and 4 He) measured in 400 and 800 MeV/nucleon Ne+Nb collisions using the large solid angle detector DIOGENE. The model reproduces quite well global experimental observables like nuclear fragment multiplicity distributions or production cross-sections, and nuclear fragment to proton ratios. For rapidity distributions the best agreement occurs for peripheral reactions. Transverse momentum analysis confirms once again that the cascade, although being a microscopic approach, gives too small a collective flow. For heavier nuclear fragments conclusions are not so clear. Since the cross-sections are the main ingredients of the detailed treatment of the first stage of the reaction by the intranuclear cascade, such an approach can be very fruitful in order to infer informations on effective nucleon-nucleon cross-sections. (authors). 31 refs., 23 figs., 6 tabs

  10. Translation in ESL Classes

    Directory of Open Access Journals (Sweden)

    Nagy Imola Katalin

    2015-12-01

    Full Text Available The problem of translation in foreign language classes cannot be dealt with unless we attempt to make an overview of what translation meant for language teaching in different periods of language pedagogy. From the translation-oriented grammar-translation method through the complete ban on translation and mother tongue during the times of the audio-lingual approaches, we have come today to reconsider the role and status of translation in ESL classes. This article attempts to advocate for translation as a useful ESL class activity, which can completely fulfil the requirements of communicativeness. We also attempt to identify some activities and games, which rely on translation in some books published in the 1990s and the 2000s.

  11. Spallation reactions; Reactions de spallation

    Energy Technology Data Exchange (ETDEWEB)

    Cugon, J.

    1996-12-31

    Spallation reactions dominate the interactions of hadrons with nuclei in the GeV range (from {approx} 0.1 to {approx} 10 GeV). They correspond to a sometimes important ejection of light particles leaving most of the time a residue of mass commensurate with the target mass. The main features of the experimental data are briefly reviewed. The most successful theoretical model, namely the intranuclear cascade + evaporation model, is presented. Its physical content, results and possible improvements are critically discussed. Alternative approaches are shortly reviewed. (author). 84 refs.

  12. A Machine Learning Approach to the Detection of Pilot’s Reaction to Unexpected Events Based on EEG Signals

    Directory of Open Access Journals (Sweden)

    Bartosz Binias

    2018-01-01

    Full Text Available This work considers the problem of utilizing electroencephalographic signals for use in systems designed for monitoring and enhancing the performance of aircraft pilots. Systems with such capabilities are generally referred to as cognitive cockpits. This article provides a description of the potential that is carried by such systems, especially in terms of increasing flight safety. Additionally, a neuropsychological background of the problem is presented. Conducted research was focused mainly on the problem of discrimination between states of brain activity related to idle but focused anticipation of visual cue and reaction to it. Especially, a problem of selecting a proper classification algorithm for such problems is being examined. For that purpose an experiment involving 10 subjects was planned and conducted. Experimental electroencephalographic data was acquired using an Emotiv EPOC+ headset. Proposed methodology involved use of a popular method in biomedical signal processing, the Common Spatial Pattern, extraction of bandpower features, and an extensive test of different classification algorithms, such as Linear Discriminant Analysis, k-nearest neighbors, and Support Vector Machines with linear and radial basis function kernels, Random Forests, and Artificial Neural Networks.

  13. Safety class methodology

    International Nuclear Information System (INIS)

    Donner, E.B.; Low, J.M.; Lux, C.R.

    1992-01-01

    DOE Order 6430.1A, General Design Criteria (GDC), requires that DOE facilities be evaluated with respect to ''safety class items.'' Although the GDC defines safety class items, it does not provide a methodology for selecting safety class items. The methodology described in this paper was developed to assure that Safety Class Items at the Savannah River Site (SRS) are selected in a consistent and technically defensible manner. Safety class items are those in the highest of four categories determined to be of special importance to nuclear safety and, merit appropriately higher-quality design, fabrication, and industrial test standards and codes. The identification of safety class items is approached using a cascading strategy that begins at the 'safety function' level (i.e., a cooling function, ventilation function, etc.) and proceeds down to the system, component, or structure level. Thus, the items that are required to support a safety function are SCls. The basic steps in this procedure apply to the determination of SCls for both new project activities, and for operating facilities. The GDC lists six characteristics of SCls to be considered as a starting point for safety item classification. They are as follows: 1. Those items whose failure would produce exposure consequences that would exceed the guidelines in Section 1300-1.4, ''Guidance on Limiting Exposure of the Public,'' at the site boundary or nearest point of public access 2. Those items required to maintain operating parameters within the safety limits specified in the Operational Safety Requirements during normal operations and anticipated operational occurrences. 3. Those items required for nuclear criticality safety. 4. Those items required to monitor the release of radioactive material to the environment during and after a Design Basis Accident. Those items required to achieve, and maintain the facility in a safe shutdown condition 6. Those items that control Safety Class Item listed above

  14. Biogenic uraninite precipitation and its reoxidation by iron(III) (hydr)oxides: A reaction modeling approach

    Science.gov (United States)

    Spycher, Nicolas F.; Issarangkun, Montarat; Stewart, Brandy D.; Sevinç Şengör, S.; Belding, Eileen; Ginn, Tim R.; Peyton, Brent M.; Sani, Rajesh K.

    2011-08-01

    One option for immobilizing uranium present in subsurface contaminated groundwater is in situ bioremediation, whereby dissimilatory metal-reducing bacteria and/or sulfate-reducing bacteria are stimulated to catalyze the reduction of soluble U(VI) and precipitate it as uraninite (UO 2). This is typically accomplished by amending groundwater with an organic electron donor. It has been shown, however, that once the electron donor is entirely consumed, Fe(III) (hydr)oxides can reoxidize biogenically produced UO 2, thus potentially impeding cleanup efforts. On the basis of published experiments showing that such reoxidation takes place even under highly reducing conditions (e.g., sulfate-reducing conditions), thermodynamic and kinetic constraints affecting this reoxidation are examined using multicomponent biogeochemical simulations, with particular focus on the role of sulfide and Fe(II) in solution. The solubility of UO 2 and Fe(III) (hydr)oxides are presented, and the effect of nanoscale particle size on stability is discussed. Thermodynamically, sulfide is preferentially oxidized by Fe(III) (hydr)oxides, compared to biogenic UO 2, and for this reason the relative rates of sulfide and UO 2 oxidation play a key role on whether or not UO 2 reoxidizes. The amount of Fe(II) in solution is another important factor, with the precipitation of Fe(II) minerals lowering the Fe +2 activity in solution and increasing the potential for both sulfide and UO 2 reoxidation. The greater (and unintuitive) UO 2 reoxidation by hematite compared to ferrihydrite previously reported in some experiments can be explained by the exhaustion of this mineral from reaction with sulfide. Simulations also confirm previous studies suggesting that carbonate produced by the degradation of organic electron donors used for bioreduction may significantly increase the potential for UO 2 reoxidation through formation of uranyl carbonate aqueous complexes.

  15. Footwear width and balance-recovery reactions: A new approach to improving lateral stability in older adults.

    Science.gov (United States)

    Yamaguchi, Takeshi; Cheng, Kenneth C; McKay, Sandra M; Maki, Brian E

    Age-related difficulty in controlling lateral stability is of crucial importance because lateral falls increase risk of debilitating hip-fracture injury. This study examined whether a small increase in footwear sole width can improve ability of older adults to regain lateral stability subsequent to balance perturbation. The study involved sixteen healthy, ambulatory, community-dwelling older adults (aged 65-78). Widened base-of-support (WBOS) footwear was simulated by affixing polystyrene-foam blocks (20mm wide) on the medial and lateral sides of rubber overshoes; unaltered overshoes were worn in normal (NBOS) trials. Balance perturbations were applied using a motion platform. Gait, mobility and agility tests revealed no adverse effects of wearing the WBOS footwear. Lateral-perturbation tests showed that the WBOS footwear improved ability to stabilize the body without stepping (p=0.002). Depending on the perturbation magnitude, the frequency of stepping was reduced by up to 25% (64% of NBOS trials vs 39% of WBOS trials). In addition, the WBOS footwear appeared to improve ability to maintain lateral stability during forward-step reactions, as evidenced by reduced incidence of additional lateral steps (p=0.04) after stepping over an obstacle in response to a forward-fall perturbation. A small increase in sole width can improve certain aspects of lateral stability in older adults, without compromising mobility and agility. This finding supports the viability of WBOS footwear as an intervention to improve balance. Further research is needed to test populations with more severe balance impairments, examine user compliance, and determine if WBOS footwear actually reduces falling risk in daily life.

  16. CoFe2O4-TiO2 Hybrid Nanomaterials: Synthesis Approaches Based on the Oil-in-Water Microemulsion Reaction Method

    Directory of Open Access Journals (Sweden)

    Arturo Adrián Rodríguez-Rodríguez

    2017-01-01

    Full Text Available CoFe2O4 nanoparticles decorated and wrapped with TiO2 nanoparticles have been prepared by mixing well-dispersed CoFe2O4 with amorphous TiO2 (impregnation approach and growing amorphous TiO2 over the magnetic core (seed approach, respectively, followed by thermal treatment to achieve TiO2 crystallinity. Synthesis strategies were based on the oil-in-water microemulsion reaction method. Thermally treated nanomaterials were characterized in terms of structure, morphology, and composition, to confirm hybrid nanoparticles formation and relate with the synthesis approaches; textural, optical, and magnetic properties were evaluated. X-ray diffraction revealed coexistence of cubic spinel-type CoFe2O4 and tetragonal anatase TiO2. Electron microscopy images depicted crystalline nanoparticles (sizes below 25 nm, with homogeneous Ti distribution for the hybrid nanoparticles synthesized by seed approach. EDX microanalysis and ICP-AES corroborated established chemical composition. XPS evidenced chemical states, as well as TiO2 predominance over CoFe2O4 surface. According to BET measurements, the hybrid nanoparticles were mesoporous. UV-Vis spectroscopy showed optical response along the UV-visible light region. Magnetic properties suggested the breaking order of magnetic domains due to modification with TiO2, especially for mediated seed approach sample. The properties of the obtained hybrid nanoparticles were different in comparison with its individual components. The results highlight the usefulness of designed microemulsion approaches for the straightforward synthesis of CoFe2O4-TiO2 nanostructured hybrids.

  17. Physical education resources, class management, and student physical activity levels: a structure-process-outcome approach to evaluating physical education effectiveness.

    Science.gov (United States)

    Bevans, Katherine B; Fitzpatrick, Leslie-Anne; Sanchez, Betty M; Riley, Anne W; Forrest, Christopher

    2010-12-01

    This study was conducted to empirically evaluate specific human, curricular, and material resources that maximize student opportunities for physical activity during physical education (PE) class time. A structure-process-outcome model was proposed to identify the resources that influence the frequency of PE and intensity of physical activity during PE. The proportion of class time devoted to management was evaluated as a potential mediator of the relations between resource availability and student activity levels. Data for this cross-sectional study were collected from interviews conducted with 46 physical educators and the systematic observation of 184 PE sessions in 34 schools. Regression analyses were conducted to test for the main effects of resource availability and the mediating role of class management. Students who attended schools with a low student-to-physical educator ratio had more PE time and engaged in higher levels of physical activity during class time. Access to adequate PE equipment and facilities was positively associated with student activity levels. The availability of a greater number of physical educators per student was found to impact student activity levels by reducing the amount of session time devoted to class management. The identification of structure and process predictors of student activity levels in PE will support the allocation of resources and encourage instructional practices that best support increased student activity levels in the most cost-effective way possible. Implications for PE policies and programs are discussed. © 2010, American School Health Association.

  18. Stepped MS(All) Relied Transition (SMART): An approach to rapidly determine optimal multiple reaction monitoring mass spectrometry parameters for small molecules.

    Science.gov (United States)

    Ye, Hui; Zhu, Lin; Wang, Lin; Liu, Huiying; Zhang, Jun; Wu, Mengqiu; Wang, Guangji; Hao, Haiping

    2016-02-11

    Multiple reaction monitoring (MRM) is a universal approach for quantitative analysis because of its high specificity and sensitivity. Nevertheless, optimization of MRM parameters remains as a time and labor-intensive task particularly in multiplexed quantitative analysis of small molecules in complex mixtures. In this study, we have developed an approach named Stepped MS(All) Relied Transition (SMART) to predict the optimal MRM parameters of small molecules. SMART requires firstly a rapid and high-throughput analysis of samples using a Stepped MS(All) technique (sMS(All)) on a Q-TOF, which consists of serial MS(All) events acquired from low CE to gradually stepped-up CE values in a cycle. The optimal CE values can then be determined by comparing the extracted ion chromatograms for the ion pairs of interest among serial scans. The SMART-predicted parameters were found to agree well with the parameters optimized on a triple quadrupole from the same vendor using a mixture of standards. The parameters optimized on a triple quadrupole from a different vendor was also employed for comparison, and found to be linearly correlated with the SMART-predicted parameters, suggesting the potential applications of the SMART approach among different instrumental platforms. This approach was further validated by applying to simultaneous quantification of 31 herbal components in the plasma of rats treated with a herbal prescription. Because the sMS(All) acquisition can be accomplished in a single run for multiple components independent of standards, the SMART approach are expected to find its wide application in the multiplexed quantitative analysis of complex mixtures. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. A facile template approach for the synthesis of mesoporous Fe3C/Fe-N-doped carbon catalysts for efficient and durable oxygen reduction reaction

    Institute of Scientific and Technical Information of China (English)

    Shuai Li; Bo Li; Liang Ma; Jia Yang; Hangxun Xu

    2017-01-01

    Facile synthetic approaches toward the development of efficient and durable nonprecious metal catalysts for the oxygen reduction reaction (ORR) are very important for commercializing advanced electrochemical devices such as fuel cells and metal-air batteries.Here we report a novel template approach to synthesize mesoporous Fe-N-doped carbon catalysts encapsulated with Fe3C nanoparticles.In this approach,the layer-structured FeOCl was first used as a template for the synthesis of a three-dimensional polypyrrole (PPy) structure.During the removal of the FeOCl template,the Fe3+ can be absorbed by PPy and then converted into Fe3C nanoparticles and Fe-N-C sites during the pyrolyzing process.As a result,the as-prepared catalysts could exhibit superior electrocatalytic ORR performance to the commercial Pt/C catalyst in alkaline solutions.Furthermore,the Zn-air battery assembled using the mesoporous carbon catalyst as the air electrode could surpass the commercial Pt/C catalyst in terms of the power density and energy density.

  20. Analysis of the 7Be (P, γ) 8B reaction at extremely low energies within the modified two-body potential approach

    International Nuclear Information System (INIS)

    Sanetullaev, A.; Igamov, S.B.; Yarmukhamedov, R.

    2004-01-01

    Full text: Obtaining the extremely low energy cross sections for the reaction 7 Be(p,γ ) 8 B is of great interest for a reliable estimation of the rate of this reaction, which is crucial for an accurate determination of the solar neutrino flux. At present, in current literature, there is a rather wide spread in estimation of this rate (see, for instance, Ref. [1] and references therein). In this work, the modified two-body potential approach for analysis of the astrophysical S- factor S(E) for the peripheral direct radiative capture 7 Be(p,γ ) 8 B reaction of astrophysical interest is applied, in which the additional conditions of verification of the peripheral character of the reaction under consideration are formulated. The method involves the information on the asymptotic normalization coefficient (ANC) for the virtual decay 8 B → 7 Be+p and allows one to exclude the model dependence of the calculated direct astrophysical S-factor S(E) on the geometric parameters (radius r 0 and diffuseness a) of the adopted Woods-Saxon potential, which is usually used for calculations both for the two-body ( 7 Be+p)-bound state and for the 7 Be p -scattering state. The rather precise experimental astrophysical S-factor, S exp (E), in the energy range 100 7 Be(p,γ ) 8 B reaction, measured recently by the authors of Ref. [1] is used for the analysis. It is demonstrated that at extremely low energies this reaction is strongly peripheral and the measured S exp (E) can be used as an independent source of getting the information about the ANC. The new information about values of the ANC is obtained with an estimation of the weighted mean errors for them, which involves both the experimental errors of the S exp (E), and uncertainty of the method not exceeding 4%. The extracted value of the ANC is equal to C 2 =C 2 1/2 +C 2 3/2 =5.68± 0.15 fm -1 , where the indices show the value total angular momentum of the proton in the (p+ 7 Be)-bound state of 8 B. It was also demonstrated

  1. Understanding Analysis Macroscopic, microscopic, and Acid-Base Titration Symbolic Student Class XI Science High School and Improvement Efforts Microscopy Approach

    Directory of Open Access Journals (Sweden)

    Putu Indrayani

    2014-06-01

    Full Text Available Analisis Pemahaman Makroskopik, Mikroskopik, dan Simbolik Titrasi Asam-Basa Siswa Kelas XI IPA SMA serta Upaya Perbaikannya dengan Pendekatan Mikroskopik Abstract: This study aims to determine: (1 the level of understanding of the macroscopic, microscopic and symbolic students; (2 the error understanding of macroscopic, microscopic and symbolic students; (3 the effectiveness of the microscopic approach in an effort to improve students' ability to solve the problems macroscopic, symbolic and microscopic material acid-base titration. This research uses descriptive research design and quasi-experimental research design. Data research is the understanding of macroscopic, symbolic and microscopic students on the material acid-base titration. Student comprehension test measured with instruments that include: (1 macroscopic comprehension tests, (2 test the understanding of symbolic, and (3 understanding of the microscopic tests. Content validity was tested by a team of experts and the reliability of test questions macroscopic and microscopic calculated using the Spearman-Brown while reliability symbolic test item was calculated using Cronbach's Alpha. Data were analyzed using descriptive analysis and statistical tests using Anacova. Results of the study are as follows. (1 The level of understanding of the macroscopic students is high, while the symbolic and microscopic levels of understanding of students is very low. (2 Errors identified macroscopic understanding is that students do not understand that the color shown by indicators related to the nature of the solution. Symbolic understanding of the identified errors are: (i the student can not write ionization reaction; and (ii students can not choose the formula used to calculate the pH of the solution. Errors identified microscopic understanding is that students can not provide a microscopic picture of a solution of a strong acid, strong base, weak acid, weak base, and salt solutions because they do

  2. Ultralow k films by using a plasma-enhanced chemical vapor deposition porogen approach: Study of the precursor reaction mechanisms

    International Nuclear Information System (INIS)

    Castex, A.; Jousseaume, V.; Deval, J.; Bruat, J.; Favennec, L.; Passemard, G.

    2008-01-01

    As interconnects are scaled down, much effort is made to achieve ultralow k material with a dielectric constant lower than 2.5. Thus, many new precursors are investigated in plasma-enhanced chemical vapor deposition. This is particularly true with the porogen approach where two molecules are used: an organosilicon to create the silicon matrix and an organic molecule ''porogen'' that creates material porosity during a post-treatment such as annealing. In this article, the influence of the organosilicon molecular structure is investigated. Two ''matrix precursors'' with different structures are therefore compared. The first one, referred to as D5, has a ring structure (decamethyl pentacyclosiloxane); the second one, referred to as DEOMS, has a star structure (diethoxymethyl silane). The porogen organic molecule, referred to as CHO, is cyclohexen oxide. The fragmentation paths of the precursor molecules in the plasma are investigated by quadrupole mass spectroscopy and the film structure is studied by Fourier transform infrared spectroscopy. The mass spectroscopy analysis shows that the fragmentation in plasma is highest for DEOMS, intermediate for CHO, and lowest for D5 in comparable process conditions. At the maximum plasma power setting, the loss rate, which yields molecule consumption, is 43%-81% for the D5-CHO mixture, respectively, and 73%-37% for the DEOMS-CHO mixture, respectively. This is related to higher bond-dissociation energy for the siloxane (Si-O-Si) link in D5 than silane (Si-H), silylethoxyde (Si-OC 2 H 5 ) in DEOMS, or C-C and epoxy cycle in CHO. Indeed, a higher electron-energy relative threshold for dissociation under electron impact is measured for D5 (around 7 eV) than for DEOMS and CHO (around 4 eV). Moreover, the fragment structures differ from one precursor to another. Methyl groups are abstracted from D5 and a few polysiloxane chains are produced from pentacycle opening and fragmentation. In the case of DEOMS, many single silicon

  3. Precompound Reactions: Basic Concepts

    International Nuclear Information System (INIS)

    Weidenmueller, H. A.

    2008-01-01

    Because of the non-zero nuclear equilibration time, the compound-nucleus scattering model fails when the incident energy exceeds 10 or 20 MeV, and precompound reactions become important. Basic ideas used in the quantum-statistical approaches to these reactions are described

  4. Targeted Quantitation of Site-Specific Cysteine Oxidation in Endogenous Proteins Using a Differential Alkylation and Multiple Reaction Monitoring Mass Spectrometry Approach

    Science.gov (United States)

    Held, Jason M.; Danielson, Steven R.; Behring, Jessica B.; Atsriku, Christian; Britton, David J.; Puckett, Rachel L.; Schilling, Birgit; Campisi, Judith; Benz, Christopher C.; Gibson, Bradford W.

    2010-01-01

    Reactive oxygen species (ROS) are both physiological intermediates in cellular signaling and mediators of oxidative stress. The cysteine-specific redox-sensitivity of proteins can shed light on how ROS are regulated and function, but low sensitivity has limited quantification of the redox state of many fundamental cellular regulators in a cellular context. Here we describe a highly sensitive and reproducible oxidation analysis approach (OxMRM) that combines protein purification, differential alkylation with stable isotopes, and multiple reaction monitoring mass spectrometry that can be applied in a targeted manner to virtually any cysteine or protein. Using this approach, we quantified the site-specific cysteine oxidation status of endogenous p53 for the first time and found that Cys182 at the dimerization interface of the DNA binding domain is particularly susceptible to diamide oxidation intracellularly. OxMRM enables analysis of sulfinic and sulfonic acid oxidation levels, which we validate by assessing the oxidation of the catalytic Cys215 of protein tyrosine phosphatase-1B under numerous oxidant conditions. OxMRM also complements unbiased redox proteomics discovery studies as a verification tool through its high sensitivity, accuracy, precision, and throughput. PMID:20233844

  5. Path-oriented early reaction to approaching disruptions in ASDEX Upgrade and TCV in view of the future needs for ITER and DEMO

    Science.gov (United States)

    Maraschek, M.; Gude, A.; Igochine, V.; Zohm, H.; Alessi, E.; Bernert, M.; Cianfarani, C.; Coda, S.; Duval, B.; Esposito, B.; Fietz, S.; Fontana, M.; Galperti, C.; Giannone, L.; Goodman, T.; Granucci, G.; Marelli, L.; Novak, S.; Paccagnella, R.; Pautasso, G.; Piovesan, P.; Porte, L.; Potzel, S.; Rapson, C.; Reich, M.; Sauter, O.; Sheikh, U.; Sozzi, C.; Spizzo, G.; Stober, J.; Treutterer, W.; ZancaP; ASDEX Upgrade Team; TCV Team; the EUROfusion MST1 Team

    2018-01-01

    Routine reaction to approaching disruptions in tokamaks is currently largely limited to machine protection by mitigating an ongoing disruption, which remains a basic requirement for ITER and DEMO [1]. Nevertheless, a mitigated disruption still generates stress to the device. Additionally, in future fusion devices, high-performance discharge time itself will be very valuable. Instead of reacting only on generic features, occurring shortly before the disruption, the ultimate goal is to actively avoid approaching disruptions at an early stage, sustain the discharges whenever possible and restrict mitigated disruptions to major failures. Knowledge of the most relevant root causes and the corresponding chain of events leading to disruption, the disruption path, is a prerequisite. For each disruption path, physics-based sensors and adequate actuators must be defined and their limitations considered. Early reaction facilitates the efficiency of the actuators and enhances the probability of a full recovery. Thus, sensors that detect potential disruptions in time are to be identified. Once the entrance into a disruption path is detected, we propose a hierarchy of actions consisting of (I) recovery of the discharge to full performance or at least continuation with a less disruption-prone backup scenario, (II) complete avoidance of disruption to sustain the discharge or at least delay it for a controlled termination and, (III), only as last resort, a disruption mitigation. Based on the understanding of disruption paths, a hierarchical and path-specific handling strategy must be developed. Such schemes, testable in present devices, could serve as guidelines for ITER and DEMO operation. For some disruption paths, experiments have been performed at ASDEX Upgrade and TCV. Disruptions were provoked in TCV by impurity injection into ELMy H-mode discharges and in ASDEX Upgrade by forcing a density limit in H-mode discharges. The new approach proposed in this paper is discussed for

  6. Flexible Word Classes

    DEFF Research Database (Denmark)

    • First major publication on the phenomenon • Offers cross-linguistic, descriptive, and diverse theoretical approaches • Includes analysis of data from different language families and from lesser studied languages This book is the first major cross-linguistic study of 'flexible words', i.e. words...... that cannot be classified in terms of the traditional lexical categories Verb, Noun, Adjective or Adverb. Flexible words can - without special morphosyntactic marking - serve in functions for which other languages must employ members of two or more of the four traditional, 'specialised' word classes. Thus......, flexible words are underspecified for communicative functions like 'predicating' (verbal function), 'referring' (nominal function) or 'modifying' (a function typically associated with adjectives and e.g. manner adverbs). Even though linguists have been aware of flexible world classes for more than...

  7. Inverse-Electron-Demand Diels-Alder Reactions: Principles and Applications.

    Science.gov (United States)

    Png, Zhuang Mao; Zeng, Huining; Ye, Qun; Xu, Jianwei

    2017-09-05

    Inverse-electron-demand Diels-Alder (iEDDA) reactions are an intriguing class of cycloaddition reactions that have attracted increasing attention for their application in bioorthogonal chemistry, the total synthesis of natural products, and materials science. In many cases, the application of the iEDDA reaction has been demonstrated as an innovative approach to achieve target structures. The theoretical aspects of this class of reactions are of particular interest for scientists as a means to understand the various factors, such as steric strain and electron density of the attached groups, that govern the reaction and thus to elucidate the reaction mechanism. This review aims to summarize both theoretical investigations and application-driven research work on the iEDDA reaction. First, the historical aspects and the theoretical basis of the reaction, especially recent advances in time-dependent density functional theory (TD-DFT) calculations, as well as catalysis strategies will be highlighted and discussed. Second, the applications of this novel reaction in the context of materials science, bioorthogonal chemistry, and total synthesis of natural products will be elaborated with selected recent examples. The challenges and opportunities of the iEDDA reaction will be highlighted to give more insight into its potential applications in many other research areas. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Modeling the pH and temperature dependence of aqueousphase hydroxyl radical reaction rate constants of organic micropollutants using QSPR approach.

    Science.gov (United States)

    Gupta, Shikha; Basant, Nikita

    2017-11-01

    Designing of advanced oxidation process (AOP) requires knowledge of the aqueous phase hydroxyl radical ( ● OH) reactions rate constants (k OH ), which are strictly dependent upon the pH and temperature of the medium. In this study, pH- and temperature-dependent quantitative structure-property relationship (QSPR) models based on the decision tree boost (DTB) approach were developed for the prediction of k OH of diverse organic contaminants following the OECD guidelines. Experimental datasets (n = 958) pertaining to the k OH values of aqueous phase reactions at different pH (n = 470; 1.4 × 10 6 to 3.8 × 10 10  M -1  s -1 ) and temperature (n = 171; 1.0 × 10 7 to 2.6 × 10 10  M -1  s -1 ) were considered and molecular descriptors of the compounds were derived. The Sanderson scale electronegativity, topological polar surface area, number of double bonds, and halogen atoms in the molecule, in addition to the pH and temperature, were found to be the relevant predictors. The models were validated and their external predictivity was evaluated in terms of most stringent criteria parameters derived on the test data. High values of the coefficient of determination (R 2 ) and small root mean squared error (RMSE) in respective training (> 0.972, ≤ 0.12) and test (≥ 0.936, ≤ 0.16) sets indicated high generalization and predictivity of the developed QSPR model. Other statistical parameters derived from the training and test data also supported the robustness of the models and their suitability for screening new chemicals within the defined chemical space. The developed QSPR models provide a valuable tool for predicting the ● OH reaction rate constants of emerging new water contaminants for their susceptibility to AOPs.

  9. A Virtual Class Calculus

    DEFF Research Database (Denmark)

    Ernst, Erik; Ostermann, Klaus; Cook, William Randall

    2006-01-01

    Virtual classes are class-valued attributes of objects. Like virtual methods, virtual classes are defined in an object's class and may be redefined within subclasses. They resemble inner classes, which are also defined within a class, but virtual classes are accessed through object instances...... model for virtual classes has been a long-standing open question. This paper presents a virtual class calculus, vc, that captures the essence of virtual classes in these full-fledged programming languages. The key contributions of the paper are a formalization of the dynamic and static semantics of vc...

  10. Classification of protein fold classes by knot theory and prediction of folds by neural networks: A combined theoretical and experimental approach

    DEFF Research Database (Denmark)

    Ramnarayan, K.; Bohr, Henrik; Jalkanen, Karl J.

    2008-01-01

    We present different means of classifying protein structure. One is made rigorous by mathematical knot invariants that coincide reasonably well with ordinary graphical fold classification and another classification is by packing analysis. Furthermore when constructing our mathematical fold...... classifications, we utilize standard neural network methods for predicting protein fold classes from amino acid sequences. We also make an analysis of the redundancy of the structural classifications in relation to function and ligand binding. Finally we advocate the use of combining the measurement of the VA...

  11. A generic approach for expanding homolog-targeted residue screening of sulfonamides using a fast matrix separation and class-specific fragmentation-dependent acquisition with a hybrid quadrupole-linear ion trap mass spectrometer

    International Nuclear Information System (INIS)

    Huang Chunlin; Guo Bin; Wang Xiaoying; Li Jie; Zhu Weitao; Chen Bo; Ouyang Shan; Yao Shouzhuo

    2012-01-01

    Highlights: ► Generic homolog-targeted screening approach for multi-residual sulfonamide analogs. ► Single-tube extraction/partitioning-multifunction adsorption cleanup for direct injection. ► Class-specific fragmentation for expanding coverage of N 4 -acetyl and N-OH metabolites. ► PreS–IDA–EPI in LC–QqLIT for simultaneous screening and confirmation of real samples. - Abstract: A generic and efficient homolog-targeted approach was used to expand screening and detection of target class of sulfonamides and structural analogs, based on a fast single-tube extraction/partitioning-multifunction adsorption cleanup (SEP/MAC) for class-specific fragmentation-dependent acquisition with a liquid chromatography–hybrid triple-quadrupole linear ion trap mass spectrometer (LC–QqLIT). By combining the two-stage process conducted in a single tube as one-pot protocol, the straightforward SEP/MAC procedure was optimized to offer clean extracts with reasonable recovery (71–109% with RSDs 4 -acetyl and hydroxylamine metabolites plus their possible dimers. Moreover, the PreS-triggered automatically enhanced product ion spectral acquisition enabled simultaneous screening, profiling and confirmation of an unlimited number of analytes belonging to the sulfonamide class within a single analysis. The validation and application results of the generic SEP/MAC-based LC–QqLIT strategy consistently demonstrated favorable performances with acceptable accuracy (67–116%), precision (RSDs −1 ) to meet the acceptance criteria for all the sulfonamide–tissue combinations. Thus, the integration of the matrix-independent SEP/MAC procedure and the multiparameter matching algorithm with the unit-resolution LC–QqLIT instrument can serve as a valuable semi-targeted discovery strategy for rapid screening and reliable quantitative/confirmatory analysis of real samples.

  12. Class teacher’s gender culture

    OpenAIRE

    GOGOL-SAVRIY M.V.

    2012-01-01

    The article considers the gender approach in the professional culture of a class teacher. The nature, levels and sublevels of class teacher’s gender culture development are defined. Taking into consideration the concepts of leading researchers, the essence of components of class teacher’s gender culture is discovered according to the levels of its development as professional and educational activity. Proceeding from the results of the diagnostics of class teachers’ gender culture at comprehen...

  13. Surgical excision of Essure® devices with ESHRE Class IIb uterine malformation: sequential hysteroscopic-laparoscopic approach to the septate uterus.

    Science.gov (United States)

    Sills, E S; Palermo, G D

    2016-03-28

    While contraindications to Essure® placement have been provided by the manufacturer, there is no consensus on how best to remove these contraceptive devices. Here, we describe a non-hysterectomy removal of Essure® for a patient with a septate uterus (ESHRE Class IIb uterine malformation). A 35yr old G4 P2 presented for removal of Essure® implants after three years of gradually increasing pelvic pain, weight gain, headache, dizziness, lower extremity paresthesia, and fatigue which followed hysteroscopic sterilization (HS). Prior to HS, the patient was in good general health. She did not smoke and had never had a miscarriage. HS was performed under general anesthesia in October 2012. HSG obtained three months later, confirmed bilateral tubal occlusion but revealed an abnormal uterine cavity. A repeat HSG in 2015 showed minimal device migration, no contrast dye spill and a deeply bifid uterine cavity. At our center laparoscopic cornual dissection and bilateral partial tubal resection achieved removal of both devices intact and the patient was discharged three hours after surgery. Her postoperative recovery was uneventful. The presence of a Müllerian anomaly is a relative contraindication to the Essure® procedure. This is the first reported description of successful removal of Essure® coils in the setting of an ESHRE Class IIb uterine anomaly, and underscores the importance of careful patient selection, accurate pre-operative imaging and a conservative technique which renders hysterectomy unnecessary.

  14. Nuclear reactions

    International Nuclear Information System (INIS)

    Lane, A.M.

    1980-01-01

    In reviewing work at Harwell over the past 25 years on nuclear reactions it is stated that a balance has to be struck in both experiment and theory between work on cross-sections of direct practical relevance to reactors and on those relevant to an overall understanding of reaction processes. The compound nucleus and direct process reactions are described. Having listed the contributions from AERE, Harwell to developments in nuclear reaction research in the period, work on the optical model, neutron capture theory, reactions at doorway states with fine structure, and sum-rules for spectroscopic factors are considered in more detail. (UK)

  15. Structure-guided approach identifies a novel class of HIV-1 ribonuclease H inhibitors: binding mode insights through magnesium complexation and site-directed mutagenesis studies

    DEFF Research Database (Denmark)

    Poongavanam, Vasanthanathan; Corona, Angela; Steinmann, Casper

    2018-01-01

    is a long and expensive process that can be speeded up by in silico methods. In the present study, a structure-guided screening is coupled with a similarity-based search on the Specs database to identify a new class of HIV-1 RNase H inhibitors. Out of the 45 compounds selected for experimental testing, 15...... inhibited the RNase H function below 100 μM with three hits exhibiting IC50 values active compound, AA, inhibits HIV-1 RNase H with an IC50 of 5.1 μM and exhibits a Mg-independent mode of inhibition. Site-directed mutagenesis studies provide valuable insight into the binding mode of newly...

  16. Novel approach to characterising individuals with low back-related leg pain: cluster identification with latent class analysis and 12-month follow-up.

    Science.gov (United States)

    Stynes, Siobhán; Konstantinou, Kika; Ogollah, Reuben; Hay, Elaine M; Dunn, Kate M

    2018-04-01

    Traditionally, low back-related leg pain (LBLP) is diagnosed clinically as referred leg pain or sciatica (nerve root involvement). However, within the spectrum of LBLP, we hypothesised that there may be other unrecognised patient subgroups. This study aimed to identify clusters of patients with LBLP using latent class analysis and describe their clinical course. The study population was 609 LBLP primary care consulters. Variables from clinical assessment were included in the latent class analysis. Characteristics of the statistically identified clusters were compared, and their clinical course over 1 year was described. A 5 cluster solution was optimal. Cluster 1 (n = 104) had mild leg pain severity and was considered to represent a referred leg pain group with no clinical signs, suggesting nerve root involvement (sciatica). Cluster 2 (n = 122), cluster 3 (n = 188), and cluster 4 (n = 69) had mild, moderate, and severe pain and disability, respectively, and response to clinical assessment items suggested categories of mild, moderate, and severe sciatica. Cluster 5 (n = 126) had high pain and disability, longer pain duration, and more comorbidities and was difficult to map to a clinical diagnosis. Most improvement for pain and disability was seen in the first 4 months for all clusters. At 12 months, the proportion of patients reporting recovery ranged from 27% for cluster 5 to 45% for cluster 2 (mild sciatica). This is the first study that empirically shows the variability in profile and clinical course of patients with LBLP including sciatica. More homogenous groups were identified, which could be considered in future clinical and research settings.

  17. Ion-Molecule Reaction Dynamics.

    Science.gov (United States)

    Meyer, Jennifer; Wester, Roland

    2017-05-05

    We review the recent advances in the investigation of the dynamics of ion-molecule reactions. During the past decade, the combination of single-collision experiments in crossed ion and neutral beams with the velocity map ion imaging detection technique has enabled a wealth of studies on ion-molecule reactions. These methods, in combination with chemical dynamics simulations, have uncovered new and unexpected reaction mechanisms, such as the roundabout mechanism and the subtle influence of the leaving group in anion-molecule nucleophilic substitution reactions. For this important class of reactions, as well as for many fundamental cation-molecule reactions, the information obtained with crossed-beam imaging is discussed. The first steps toward understanding micro-solvation of ion-molecule reaction dynamics are presented. We conclude with the presentation of several interesting directions for future research.

  18. Imagining class: A study into material social class position, subjective identification, and voting behavior across Europe.

    Science.gov (United States)

    D'Hooge, Lorenzo; Achterberg, Peter; Reeskens, Tim

    2018-02-01

    The traditional approach to class voting has largely ignored the question whether material class positions coincide with subjective class identification. Following Sosnaud et al. (2013), this study evaluates party preferences when Europeans' material and subjective social class do not coincide. Seminal studies on voting behavior have suggested that members of lower classes are more likely to vote for the economic left and cultural right and that higher classes demonstrate the opposite pattern. Yet, these studies have on the one hand overlooked the possibility that there is a mismatch between the material class people can be classified in and the class they think they are part of, and on the other hand the consequences of this discordant class identification on voting behavior. Analyzing the 2009 wave of the European Elections Study, we find that the majority of the Europeans discordantly identify with the middle class, whereas only a minority of the lower and higher classes concordantly identify with their material social class. Further, material class only seems to predict economic voting behavior when it coincides with subjective class; for instance, individuals who have an inflated class identification are more likely to vote for the economic left, even when they materially can be classified as middle or high class. We conclude this paper with a discussion on scholarly debates concerning class and politics. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Real-time polymerase chain reaction-based approach for quantification of the pat gene in the T25 Zea mays event.

    Science.gov (United States)

    Weighardt, Florian; Barbati, Cristina; Paoletti, Claudia; Querci, Maddalena; Kay, Simon; De Beuckeleer, Marc; Van den Eede, Guy

    2004-01-01

    In Europe, a growing interest for reliable techniques for the quantification of genetically modified component(s) of food matrixes is arising from the need to comply with the European legislative framework on novel food products. Real-time polymerase chain reaction (PCR) is currently the most powerful technique for the quantification of specific nucleic acid sequences. Several real-time PCR methodologies based on different molecular principles have been developed for this purpose. The most frequently used approach in the field of genetically modified organism (GMO) quantification in food or feed samples is based on the 5'-3'-exonuclease activity of Taq DNA polymerase on specific degradation probes (TaqMan principle). A novel approach was developed for the establishment of a TaqMan quantification system assessing GMO contents around the 1% threshold stipulated under European Union (EU) legislation for the labeling of food products. The Zea mays T25 elite event was chosen as a model for the development of the novel GMO quantification approach. The most innovative aspect of the system is represented by the use of sequences cloned in plasmids as reference standards. In the field of GMO quantification, plasmids are an easy to use, cheap, and reliable alternative to Certified Reference Materials (CRMs), which are only available for a few of the GMOs authorized in Europe, have a relatively high production cost, and require further processing to be suitable for analysis. Strengths and weaknesses of the use of novel plasmid-based standards are addressed in detail. In addition, the quantification system was designed to avoid the use of a reference gene (e.g., a single copy, species-specific gene) as normalizer, i.e., to perform a GMO quantification based on an absolute instead of a relative measurement. In fact, experimental evidences show that the use of reference genes adds variability to the measurement system because a second independent real-time PCR-based measurement

  20. RxClass

    Data.gov (United States)

    U.S. Department of Health & Human Services — The RxClass Browser is a web application for exploring and navigating through the class hierarchies to find the RxNorm drug members associated with each class....

  1. Understanding the Influence of Race/Ethnicity, Gender, and Class on Inequalities in Academic and Non-Academic Outcomes among Eighth-Grade Students: Findings from an Intersectionality Approach

    Science.gov (United States)

    Bécares, Laia; Priest, Naomi

    2015-01-01

    Socioeconomic, racial/ethnic, and gender inequalities in academic achievement have been widely reported in the US, but how these three axes of inequality intersect to determine academic and non-academic outcomes among school-aged children is not well understood. Using data from the US Early Childhood Longitudinal Study—Kindergarten (ECLS-K; N = 10,115), we apply an intersectionality approach to examine inequalities across eighth-grade outcomes at the intersection of six racial/ethnic and gender groups (Latino girls and boys, Black girls and boys, and White girls and boys) and four classes of socioeconomic advantage/disadvantage. Results of mixture models show large inequalities in socioemotional outcomes (internalizing behavior, locus of control, and self-concept) across classes of advantage/disadvantage. Within classes of advantage/disadvantage, racial/ethnic and gender inequalities are predominantly found in the most advantaged class, where Black boys and girls, and Latina girls, underperform White boys in academic assessments, but not in socioemotional outcomes. In these latter outcomes, Black boys and girls perform better than White boys. Latino boys show small differences as compared to White boys, mainly in science assessments. The contrasting outcomes between racial/ethnic and gender minorities in self-assessment and socioemotional outcomes, as compared to standardized assessments, highlight the detrimental effect that intersecting racial/ethnic and gender discrimination have in patterning academic outcomes that predict success in adult life. Interventions to eliminate achievement gaps cannot fully succeed as long as social stratification caused by gender and racial discrimination is not addressed. PMID:26505623

  2. Understanding the Influence of Race/Ethnicity, Gender, and Class on Inequalities in Academic and Non-Academic Outcomes among Eighth-Grade Students: Findings from an Intersectionality Approach.

    Science.gov (United States)

    Bécares, Laia; Priest, Naomi

    2015-01-01

    Socioeconomic, racial/ethnic, and gender inequalities in academic achievement have been widely reported in the US, but how these three axes of inequality intersect to determine academic and non-academic outcomes among school-aged children is not well understood. Using data from the US Early Childhood Longitudinal Study-Kindergarten (ECLS-K; N = 10,115), we apply an intersectionality approach to examine inequalities across eighth-grade outcomes at the intersection of six racial/ethnic and gender groups (Latino girls and boys, Black girls and boys, and White girls and boys) and four classes of socioeconomic advantage/disadvantage. Results of mixture models show large inequalities in socioemotional outcomes (internalizing behavior, locus of control, and self-concept) across classes of advantage/disadvantage. Within classes of advantage/disadvantage, racial/ethnic and gender inequalities are predominantly found in the most advantaged class, where Black boys and girls, and Latina girls, underperform White boys in academic assessments, but not in socioemotional outcomes. In these latter outcomes, Black boys and girls perform better than White boys. Latino boys show small differences as compared to White boys, mainly in science assessments. The contrasting outcomes between racial/ethnic and gender minorities in self-assessment and socioemotional outcomes, as compared to standardized assessments, highlight the detrimental effect that intersecting racial/ethnic and gender discrimination have in patterning academic outcomes that predict success in adult life. Interventions to eliminate achievement gaps cannot fully succeed as long as social stratification caused by gender and racial discrimination is not addressed.

  3. Understanding the Influence of Race/Ethnicity, Gender, and Class on Inequalities in Academic and Non-Academic Outcomes among Eighth-Grade Students: Findings from an Intersectionality Approach.

    Directory of Open Access Journals (Sweden)

    Laia Bécares

    Full Text Available Socioeconomic, racial/ethnic, and gender inequalities in academic achievement have been widely reported in the US, but how these three axes of inequality intersect to determine academic and non-academic outcomes among school-aged children is not well understood. Using data from the US Early Childhood Longitudinal Study-Kindergarten (ECLS-K; N = 10,115, we apply an intersectionality approach to examine inequalities across eighth-grade outcomes at the intersection of six racial/ethnic and gender groups (Latino girls and boys, Black girls and boys, and White girls and boys and four classes of socioeconomic advantage/disadvantage. Results of mixture models show large inequalities in socioemotional outcomes (internalizing behavior, locus of control, and self-concept across classes of advantage/disadvantage. Within classes of advantage/disadvantage, racial/ethnic and gender inequalities are predominantly found in the most advantaged class, where Black boys and girls, and Latina girls, underperform White boys in academic assessments, but not in socioemotional outcomes. In these latter outcomes, Black boys and girls perform better than White boys. Latino boys show small differences as compared to White boys, mainly in science assessments. The contrasting outcomes between racial/ethnic and gender minorities in self-assessment and socioemotional outcomes, as compared to standardized assessments, highlight the detrimental effect that intersecting racial/ethnic and gender discrimination have in patterning academic outcomes that predict success in adult life. Interventions to eliminate achievement gaps cannot fully succeed as long as social stratification caused by gender and racial discrimination is not addressed.

  4. Diagnosing Response Style Behavior by Means of a Latent-Class Factor Approach. Socio-Demographic Correlates of Gender Role Attitudes and Perceptions of Ethnic Discrimination Reexamined

    NARCIS (Netherlands)

    Moors, G.B.D.

    2003-01-01

    It is generally accepted that response style behavior in survey research may seriously distort the measurement of attitudes and subsequent causal models that include attitudinal dimensions. However, there in no single accepted methodological approach in dealing with this issue. This article aims at

  5. Design and Implementation of a CO2 Flood Utilizing Advanced Reservoir Characterization and Horizontal Injection Wells In a Shallow Shelf Carbonate Approaching Waterflood Depletion, Class II; ANNUAL

    International Nuclear Information System (INIS)

    Czirr, K.L.; Gaddis, M.P.; Moshell, M.K.

    2002-01-01

    The principle objective of this project is to demonstrate the economic viability and widespread applicability of an innovative reservoir management and carbon dioxide (CO2) flood project development approach for improving CO2 flood project economics in shallow shelf carbonate (SSC) reservoirs

  6. The affordances of using a flipped classroom approach in the teaching of mathematics: a case study of a grade 10 mathematics class

    Science.gov (United States)

    Muir, Tracey; Geiger, Vince

    2016-03-01

    Teaching secondary mathematics has a number of challenges, including the expectations that teachers cover the prescribed curriculum, help students learn difficult concepts, prepare students for future studies, and, increasingly, that they do so incorporating digital technologies. This study investigates a teacher's, and his students', perceptions of the benefits or otherwise of a flipped classroom approach in meeting these challenges, within a prescribed curriculum context. Data collection instruments included a survey designed to investigate the nature of students' engagement with the flipped approach and semi-structured student and teacher interviews. Analysis of these data indicated that the teacher and students were positive about their experiences with a flipped classroom approach and that students were motivated to engage with the teacher-created online mathematics resources. The study adds to the limited research literature related to student and teacher perceptions of the affordances of the flipped classroom approach and has implications for secondary mathematics teachers who face the challenge of the twin demands of covering the prescribed curriculum and catering for a range of students' learning needs.

  7. Nuclear Reactions for Astrophysics and Other Applications

    Energy Technology Data Exchange (ETDEWEB)

    Escher, J E; Burke, J T; Dietrich, F S; Scielzo, N D; Ressler, J J

    2011-03-01

    Cross sections for compound-nuclear reactions are required for many applications. The surrogate nuclear reactions method provides an indirect approach for determining cross sections for reactions on unstable isotopes, which are difficult or impossible to measure otherwise. Current implementations of the method provide useful cross sections for (n,f) reactions, but need to be improved upon for applications to capture reactions.

  8. Anxiety, bulimia, drug and alcohol addiction, depression, and schizophrenia: what do you think about their aetiology, dangerousness, social distance, and treatment? A latent class analysis approach.

    Science.gov (United States)

    Mannarini, Stefania; Boffo, Marilisa

    2015-01-01

    Mental illness stigma is a serious societal problem and a critical impediment to treatment seeking for mentally ill people. To improve the understanding of mental illness stigma, this study focuses on the simultaneous analysis of people's aetiological beliefs, attitudes (i.e. perceived dangerousness and social distance), and recommended treatments related to several mental disorders by devising an over-arching latent structure that could explain the relations among these variables. Three hundred and sixty university students randomly received an unlabelled vignette depicting one of six mental disorders to be evaluated on the four variables on a Likert-type scale. A one-factor Latent Class Analysis (LCA) model was hypothesized, which comprised the four manifest variables as indicators and the mental disorder as external variable. The main findings were the following: (a) a one-factor LCA model was retrieved; (b) alcohol and drug addictions are the most strongly stigmatized; (c) a realistic opinion about the causes and treatment of schizophrenia, anxiety, bulimia, and depression was associated to lower prejudicial attitudes and social rejection. Beyond the general appraisal of mental illness an individual might have, the results generally point to the acknowledgement of the specific features of different diagnostic categories. The implications of the present results are discussed in the framework of a better understanding of mental illness stigma.

  9. Robust adaptive controller design for a class of uncertain nonlinear systems using online T-S fuzzy-neural modeling approach.

    Science.gov (United States)

    Chien, Yi-Hsing; Wang, Wei-Yen; Leu, Yih-Guang; Lee, Tsu-Tian

    2011-04-01

    This paper proposes a novel method of online modeling and control via the Takagi-Sugeno (T-S) fuzzy-neural model for a class of uncertain nonlinear systems with some kinds of outputs. Although studies about adaptive T-S fuzzy-neural controllers have been made on some nonaffine nonlinear systems, little is known about the more complicated uncertain nonlinear systems. Because the nonlinear functions of the systems are uncertain, traditional T-S fuzzy control methods can model and control them only with great difficulty, if at all. Instead of modeling these uncertain functions directly, we propose that a T-S fuzzy-neural model approximates a so-called virtual linearized system (VLS) of the system, which includes modeling errors and external disturbances. We also propose an online identification algorithm for the VLS and put significant emphasis on robust tracking controller design using an adaptive scheme for the uncertain systems. Moreover, the stability of the closed-loop systems is proven by using strictly positive real Lyapunov theory. The proposed overall scheme guarantees that the outputs of the closed-loop systems asymptotically track the desired output trajectories. To illustrate the effectiveness and applicability of the proposed method, simulation results are given in this paper.

  10. Spallation reactions: calculations

    International Nuclear Information System (INIS)

    Bertini, H.W.

    1975-01-01

    Current methods for calculating spallation reactions over various energy ranges are described and evaluated. Recent semiempirical fits to existing data will probably yield the most accurate predictions for these reactions in general. However, if the products in question have binding energies appreciably different from their isotropic neighbors and if the cross section is approximately 30 mb or larger, then the intranuclear-cascade-evaporation approach is probably better suited. (6 tables, 12 figures, 34 references) (U.S.)

  11. A straight forward approach to electrodeposit tungsten disulfide/poly(3,4-ethylenedioxythiophene) composites onto nanoporous gold for the hydrogen evolution reaction

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xinxin [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, School of Materials Science and Engineering, Shandong University, Jinan 250061 (China); Engelbrekt, Christian; Zhang, Minwei [Department of Chemistry, Technical University of Denmark (DTU), Kemitorvet 207, DK 2800 Kongens Lyngby (Denmark); Li, Zheshen [ISA, Department of Physics, Aarhus University, 8000 Aarhus (Denmark); Ulstrup, Jens [Department of Chemistry, Technical University of Denmark (DTU), Kemitorvet 207, DK 2800 Kongens Lyngby (Denmark); Zhang, Jingdong, E-mail: jz@kemi.dtu.dk [Department of Chemistry, Technical University of Denmark (DTU), Kemitorvet 207, DK 2800 Kongens Lyngby (Denmark); Si, Pengchao, E-mail: pcsi@sdu.edu.cn [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, School of Materials Science and Engineering, Shandong University, Jinan 250061 (China)

    2017-07-15

    Highlights: • Facile electrodeposition of the WS{sub 2} hybrid layer onto nanoporous gold. • Poly(3,4-ethylenedioxythiophene) was approved to enhance the HER efficiency of WS{sub 2}. • The 1.1 nm deposition layer displayed a Tafel slope of 53 mV per decade. - Abstract: 1.1 nm tungsten disulfide/poly(3,4-ethylenedioxythiophene) (PEDOT) was successfully electrodeposited on the surface of dealloyed nanoporous gold (NPG) surface to form uniform nanocomposites and offers an excellent electrocatalysis for the electrochemical dihydrogen evolution reaction (HER) in acidic media. The approach is straight forward and does not require any expensive equipment or intensive energy. The morphology and composition of the nanocomposites were structurally mapped by high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectrometry (FTIR). The roles of both the NPG substrate and PEDOT in the observed enhanced HER activity compared to planar Au-electrode surfaces and pure single-component WS{sub 2} have been deconvoluted experimentally. PEDOT itself is inert for the HER, but was found to improve significantly the conductivity and operating stability of the WS{sub 2} catalyst. The prepared nanocomposites reach the best in 2D WS{sub 2} catalyst family, exhibiting excellent electrochemical catalytic activity for the HER. The optimal electrode showed an onset potential of −164 mV vs. reversible hydrogen electrode (RHE), an apparent exchange current density as high as 0.04 mA cm{sup −2}, and a very low Tafel slope of 53 mV dec{sup −1}. These catalysts are promising electrocatalysts for generation a large amount of H{sub 2} from water.

  12. Accuracy of parasitological and immunological tests for the screening of human schistosomiasis in immigrants and refugees from African countries: An approach with Latent Class Analysis.

    Directory of Open Access Journals (Sweden)

    Anna Beltrame

    2017-06-01

    Full Text Available Schistosomiasis is a neglected infection affecting millions of people, mostly living in sub-Saharan Africa. Morbidity and mortality due to chronic infection are relevant, although schistosomiasis is often clinically silent. Different diagnostic tests have been implemented in order to improve screening and diagnosis, that traditionally rely on parasitological tests with low sensitivity. Aim of this study was to evaluate the accuracy of different tests for the screening of schistosomiasis in African migrants, in a non endemic setting.A retrospective study was conducted on 373 patients screened at the Centre for Tropical Diseases (CTD in Negrar, Verona, Italy. Biological samples were tested with: stool/urine microscopy, Circulating Cathodic Antigen (CCA dipstick test, ELISA, Western blot, immune-chromatographic test (ICT. Test accuracy and predictive values of the immunological tests were assessed primarily on the basis of the results of microscopy (primary reference standard: ICT and WB resulted the test with highest sensitivity (94% and 92%, respectively, with a high NPV (98%. CCA showed the highest specificity (93%, but low sensitivity (48%. The analysis was conducted also using a composite reference standard, CRS (patients classified as infected in case of positive microscopy and/or at least 2 concordant positive immunological tests and Latent Class Analysis (LCA. The latter two models demonstrated excellent agreement (Cohen's kappa: 0.92 for the classification of the results. In fact, they both confirmed ICT as the test with the highest sensitivity (96% and NPV (97%, moreover PPV was reasonably good (78% and 72% according to CRS and LCA, respectively. ELISA resulted the most specific immunological test (over 99%. The ICT appears to be a suitable screening test, even when used alone.The rapid test ICT was the most sensitive test, with the potential of being used as a single screening test for African migrants.

  13. Root coverage in class I gingival recession defects, combining rotated papillary pedicle graft and coronally repositioned flap, using a micro surgical approach: A clinical evaluation

    Directory of Open Access Journals (Sweden)

    Latha Tella

    2009-01-01

    Full Text Available Background: The purpose of this case study was to evaluate the success and predictability of a rotated papillary pedicle graft in combination with the coronally advanced flap using surgical loupe (2.5X magnification for the treatment of Miller′s class I gingival recession. Materials and Methods: Fifteen systemically healthy patients with isolated gingival recession underwent the procedure. The probing depth, percentage root coverage, width of the keratinized gingiva and the gain in clinical attachment, papilla width, papilla height, area of the papilla at the donor site, were recorded at baseline, 3 months and 12 months. Results: All parameters except probing pocket depth, significantly improved from baseline to 12 months. The mean recession defect of 2.67 ± 0.03 mm present at baseline reduced to 0.13 ± 0.35 mm at the end of the 3 rd months and stabilized at 0.27 ± 0.59 mm at 12 months. The mean reduction in recession depth was 2.40 ± 0.03 mm at the end of the study. Complete recession coverage was obtained in 13 of the 15 (87% of the cases treated with a mean percentage recession coverage at 12 months being 86 ± 35.19%. The gain in the width of the keratinized gingiva was 1.33 ± 0.13 mm at the end of the study. There was no postoperative morbidity from where the graft was harvested at the end of the study period. Conclusion: The use of magnification in mucogingival surgery resulted in achieving a high degree of success and predictability as well as an excellent esthetic outcome.

  14. Impacts of fast food and the food retail environment on overweight and obesity in China: a multilevel latent class cluster approach.

    Science.gov (United States)

    Zhang, Xiaoyong; van der Lans, Ivo; Dagevos, Hans

    2012-01-01

    To simultaneously identify consumer segments based on individual-level consumption and community-level food retail environment data and to investigate whether the segments are associated with BMI and dietary knowledge in China. A multilevel latent class cluster model was applied to identify consumer segments based not only on their individual preferences for fast food, salty snack foods, and soft drinks and sugared fruit drinks, but also on the food retail environment at the community level. The data came from the China Health and Nutrition Survey (CHNS) conducted in 2006 and two questionnaires for adults and communities were used. A total sample of 9788 adults living in 218 communities participated in the CHNS. We successfully identified four consumer segments. These four segments were embedded in two types of food retail environment: the saturated food retail environment and the deprived food retail environment. A three-factor solution was found for consumers' dietary knowledge. The four consumer segments were highly associated with consumers' dietary knowledge and a number of sociodemographic variables. The widespread discussion about the relationships between fast-food consumption and overweight/obesity is irrelevant for Chinese segments that do not have access to fast food. Factors that are most associated with segments with a higher BMI are consumers' (incorrect) dietary knowledge, the food retail environment and sociodemographics. The results provide valuable insight for policy interventions on reducing overweight/obesity in China. This study also indicates that despite the breathtaking changes in modern China, the impact of 'obesogenic' environments should not be assessed too strictly from a 'Western' perspective.

  15. Dyslipidemias as generating issue in Biochemistry classes

    Directory of Open Access Journals (Sweden)

    R. M. Lima

    2015-08-01

    Full Text Available The traditional didactic model is based on the transmission of the teacher's encyclopedic knowledge. In this model, the teaching of Science aims at the transmission of dominant values, regarded as absolute truths. The teacher is seen is an expert on scientific contents who transmits them to students without motivating them, and without taking into consideration their previous ideas and life experience. This model contributes to the formation of professionals who accept those values uncritically. An effective approach to break up this traditional teaching model in Biochemistry is the use of a generating issue. A Generating Issue is the starting point to the knowledge construction process which, in turn, replaces traditional models. Thus, this study aimed at developing a lesson for a 12th grade class at IF Fluminense on the following content: alcohol, carboxylic acid, ester, and esterification reaction, using dyslipidemias as the Generating Issue. To verify the value of such methodology in Biochemistry classroom, data was collected by applying a questionnaire and images with texts produced by students. In addition, they had a class based on the methodology known as Three Pedagogical Moments, proposed by Delizoicov et al. (2007. Several didactic resources designed by the authors were used, such as slide presentation, tridimensional molecular models, and a roulette game named “Bioquimicados”, based on the Facebook game “Perguntados” ("Trivia Crack". After this, students developed more grounded scientific concepts, making use of terms common in scientific language. This suggests that the use of the Generating Issue in a lesson based on problematization, and supported by a ludic activity, provided a meaningful contribution to improve the students' understanding of the scientific content. This type of non-traditional class promotes greater student motivation, resulting in meaningful learning.

  16. A generic approach for expanding homolog-targeted residue screening of sulfonamides using a fast matrix separation and class-specific fragmentation-dependent acquisition with a hybrid quadrupole-linear ion trap mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Huang Chunlin [Department of Biochemistry and Molecular Biology, School of Pharmacy and Life Science, University of South China, Hengyang 421001 (China); Guo Bin, E-mail: binnguo@126.com [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China); Wang Xiaoying [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China); Li Jie [Department of Biochemistry and Molecular Biology, School of Pharmacy and Life Science, University of South China, Hengyang 421001 (China); Zhu Weitao; Chen Bo [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China); Ouyang Shan [Food Inspection and Quarantine Center, Shenzhen Entry-Exit Inspection and Quarantine Bureau of the People' s Republic of China, Shenzhen 518067 (China); Yao Shouzhuo [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China)

    2012-08-06

    Highlights: Black-Right-Pointing-Pointer Generic homolog-targeted screening approach for multi-residual sulfonamide analogs. Black-Right-Pointing-Pointer Single-tube extraction/partitioning-multifunction adsorption cleanup for direct injection. Black-Right-Pointing-Pointer Class-specific fragmentation for expanding coverage of N{sup 4}-acetyl and N-OH metabolites. Black-Right-Pointing-Pointer PreS-IDA-EPI in LC-QqLIT for simultaneous screening and confirmation of real samples. - Abstract: A generic and efficient homolog-targeted approach was used to expand screening and detection of target class of sulfonamides and structural analogs, based on a fast single-tube extraction/partitioning-multifunction adsorption cleanup (SEP/MAC) for class-specific fragmentation-dependent acquisition with a liquid chromatography-hybrid triple-quadrupole linear ion trap mass spectrometer (LC-QqLIT). By combining the two-stage process conducted in a single tube as one-pot protocol, the straightforward SEP/MAC procedure was optimized to offer clean extracts with reasonable recovery (71-109% with RSDs < 20%) and decreased matrix interferences (-9 to 19%) of multiresidual sulfonamide extraction from different tissue samples. The novel use of neutral loss scan of 66 Da (NLS) or precursor ion scanning of m/z 108 (PreS) in positive ion mode was found to achieve more comprehensive coverage of protonated molecular ions of a wide array of sulfonamides including N{sup 4}-acetyl and hydroxylamine metabolites plus their possible dimers. Moreover, the PreS-triggered automatically enhanced product ion spectral acquisition enabled simultaneous screening, profiling and confirmation of an unlimited number of analytes belonging to the sulfonamide class within a single analysis. The validation and application results of the generic SEP/MAC-based LC-QqLIT strategy consistently demonstrated favorable performances with acceptable accuracy (67-116%), precision (RSDs < 25%), and sensitivity (LOQs {<=} 7.5 ng

  17. Exploring Class-Based Intersectionality

    Science.gov (United States)

    Block, David; Corona, Victor

    2014-01-01

    This paper argues that language, culture and identity researchers need to take the intersectionality of identity inscriptions seriously and, further to this, that an intersectional approach which emanates from an interest in social class provides a productive way to examine the lives and experience of individuals living in multicultural societies.…

  18. Using a task-based approach to teaching and learning Chinese as a Foreign Language in a university beginner's level class

    DEFF Research Database (Denmark)

    Ruan, Youjin; Duan, Xiaoju; Wang, Li

    2015-01-01

    to learning Chinese as a foreign language. Chinese culture elements were also integrated into the tasks and the learning process. By analysing seven items of a post-course survey, this paper investigates the learners’ opinions toward the task-based language teaching and learning method, as well as the methods......The task-based method is regarded as an effective approach for promoting interaction and collaboration in language learning. In a beginner Chinese language course offered as an elective at Aalborg University, Denmark, a selection of tasks was designed and used to attract the students’ interests...... used in integrating culture with the language learning in this course. The results indicated that course participants were generally positive about their learning experiences and processes during the course. They appreciated not only the task-based method, but also the ways in which culture...

  19. Modeling the interactions of a peptide-major histocompatibility class I ligand with its receptors. II. Cross-reaction between a monoclonal antibody and two alpha beta T cell receptors

    DEFF Research Database (Denmark)

    Rognan, D; Engberg, J; Stryhn, A

    2000-01-01

    -peptide pair into the Fab combining site. Interestingly, the most energetically favored binding mode shows numerous analogies to the recently determined recognition of class I MHC-peptide complexes by alpha beta T cell receptors (TCRs). The pSAN13.4.1 also binds diagonally across the MHC binding groove......The recombinant antibody, pSAN13.4.1, has a unique T cell like specificity; it binds an Influenza Hemagglutinin octapeptide (Ha255-262) in an MHC (H-2Kk)-restricted manner, and a detailed comparison of the fine specificity of pSAN13.4.1 with the fine specificity of two Ha255-262-specific, H-2Kk......-restricted T cell hybridomas has supported this contention. A three-dimensional model of pSAN13.4.1 has been derived by homology modeling techniques. Subsequently, the structure of the pSAN13.4.1 antibody in complex with the antigenic Ha-Kk ligand was derived after a flexible and automated docking of the MHC...

  20. Quasielastic reactions

    International Nuclear Information System (INIS)

    Henning, W.

    1979-01-01

    Quasielastic reaction studies, because of their capability to microscopically probe nuclear structure, are still of considerable interest in heavy-ion reactions. The recent progress in understanding various aspects of the reaction mechanism make this aim appear closer. The relation between microscopic and macroscopic behavior, as suggested, for example, by the single proton transfer data to individual final states or averaged excitation energy intervals, needs to be explored. It seems particularly useful to extend measurements to higher incident energies, to explore and understand nuclear structure aspects up to the limit of the energy range where they are important

  1. cycloaddition reactions

    Indian Academy of Sciences (India)

    Unknown

    Molecular Modeling Group, Organic Chemical Sciences, Indian Institute of Chemical Technology,. Hyderabad ... thus obtained are helpful to model the regioselectivity ... compromise to model Diels–Alder reactions involving ...... acceptance.

  2. A new, fully coupled, reaction-transport-mechanical approach to modeling the evolution of natural gas reservoirs in the Piceance Basin

    Science.gov (United States)

    Payne, Dorothy Frances

    The Piceance Basin is highly compartmented, and predicting the location and characteristics of producible reservoirs is difficult. Gas generation is an important consideration in quality and size of natural gas reserves, but it also may contribute to fracturing, and hence the creation of the reservoirs in which it is contained. The purpose of this dissertation is to use numerical modeling to study the evolution of these unconventional natural gas reservoirs in the Piceance Basin. In order to characterize the scale and structure of compartmentation in the Piceance Basin, a set of in-situ fluid pressure data were interpolated across the basin and the resulting fluid pressure distribution was analyzed. Results show complex basin- and field-scale compartmentation in the Upper Cretaceous units. There are no simple correlations between compartment location and such factors as stratigraphy, basin structure, or coal thickness and maturity. To account for gas generation in the Piceance Basin, a new chemical kinetic approach to modeling lignin maturation is developed, based primarily on structural transformations of the lignin molecule observed in naturally matured samples. This model calculates mole fractions of all species, functional group fractions, and elemental weight percents. Results show reasonable prediction of maturities at other sites in the Piceance Basin for vitrinite reflectance up to about 1.7 %Ro. The flexible design of the model allows it to be modified to account for compositionally heterogeneous source material. To evaluate the role of gas generation in this dynamical system, one-dimensional simulations have been performed using the CIRFB reaction-transport-mechanical (RTM) simulator. CIRFB accounts for compaction, fracturing, hydrocarbon generation, and multi-phase flow. These results suggest that by contributing to overpressure, gas generation has two important implications: (1) gas saturation in one unit affects fracturing in other units, thereby

  3. Type classes for mathematics in type theory

    OpenAIRE

    Spitters, Bas; Van der Weegen, Eelis

    2011-01-01

    The introduction of first-class type classes in the Coq system calls for re-examination of the basic interfaces used for mathematical formalization in type theory. We present a new set of type classes for mathematics and take full advantage of their unique features to make practical a particularly flexible approach formerly thought infeasible. Thus, we address both traditional proof engineering challenges as well as new ones resulting from our ambition to build upon this development a library...

  4. Catalytic Organometallic Reactions of Ammonia

    Science.gov (United States)

    Klinkenberg, Jessica L.

    2012-01-01

    Until recently, ammonia had rarely succumbed to catalytic transformations with homogeneous catalysts, and the development of such reactions that are selective for the formation of single products under mild conditions has encountered numerous challenges. However, recently developed catalysts have allowed several classes of reactions to create products with nitrogen-containing functional groups from ammonia. These reactions include hydroaminomethylation, reductive amination, alkylation, allylic substitution, hydroamination, and cross-coupling. This Minireview describes examples of these processes and the factors that control catalyst activity and selectivity. PMID:20857466

  5. Two approaches to the clinical dilemma of treating TTP with therapeutic plasma exchange in patients with a history of anaphylactic reactions to plasma.

    Science.gov (United States)

    Sidhu, Davinder; Snyder, Edward L; Tormey, Christopher A

    2017-06-01

    Thrombotic thrombocytopenic purpura (TTP) is a rare but serious disease caused by autoantibody-mediated deficiency in von Willebrand factor (VWF) cleaving protease, ADAMTS-13. The primary acute treatment is therapeutic plasma exchange (TPE). However, some patients can develop allergic/anaphylactic reactions to the replacement (i.e., donor) plasma over time. Two potential treatment strategies for patients with TTP who demonstrate severe allergic reactions to plasma used for exchange were examined. Two patients with TTP exacerbations who developed severe allergic reactions to donor plasma were identified. One patient's TPE was re-initiated with Octaplas, a lot-batched solvent and detergent treated, type-specific, pooled donor plasma product. The other patient was exchanged with primarily albumin, followed by slow incremental exposures to donor plasma to mitigate exposures and allergic risks. Both patients were assessed for anaphylaxis. Both treatment strategies were successful in preventing any further clinically significant allergic/anaphylactic reactions and facilitated both patients' TTP remissions. Based on our experience with two similar patients with TTP exacerbations and history of anaphylactic reactions to plasma during TPE, we have identified two possible treatment protocols to achieve remission in this clinical dilemma. Substituting Octaplas for standard plasma or, alternatively, using albumin with slowly increasing amounts of standard plasma may help to mitigate the risk of further anaphylactic adverse events. J. Clin. Apheresis 32:158-162, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Exact criteria for uniqueness and multiplicity of an nth order chemical reaction via catastrophe theory approach. [Determines boundaries between unique and multiple steady state conditions

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H C; Calo, J M

    1979-01-01

    A simple, generalized technique for the exact determination of the boundaries between regions of unique and of multiple solutions to certain nonlinear equations was developed by applying catastrophe theory to the mapping of implicit and explicit functions. Its application to an nth order reaction in continuous stirred tank reactor (CSTR) yields exact, explicit expressions for the boundaries between regions of single and multiple steady states, expressed in terms of the dimensionless heat transfer coefficient and activation energy. An exact implicit expression for the boundaries between regions of uniqueness and multiplicity was also derived for an nth order reaction in a catalyst particle with an intraparticle concentration gradient and uniform temperature and is fully demonstrated for the first-order reaction. In addition, explicit criteria were developed by assuming the limits on d ln g/d ln q, where g is the effectiveness factor and q the Thiele modulus, proposed by van den Bosch and Luss.

  7. Reaction schemes of immunoanalysis

    International Nuclear Information System (INIS)

    Delaage, M.; Barbet, J.

    1991-01-01

    The authors apply a general theory for multiple equilibria to the reaction schemes of immunoanalysis, competition and sandwich. This approach allows the manufacturer to optimize the system and provide the user with interpolation functions for the standard curve and its first derivative as well, thus giving access to variance [fr

  8. Direct Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Austern, N. [University of Pittsburgh, Pittsburgh, PA (United States)

    1963-01-15

    In order to give a unified presentation of one point of view, these lectures are devoted only to a detailed development of the standard theories of direct reactions, starting from basic principles. Discussion is given of the present status of the theories, of the techniques used for practical calculation, and of possible future developments. The direct interaction (DI) aspects of a reaction are those which involve only a few of the many degrees of freedom of a nucleus. In fact the minimum number of degrees of freedom which must be involved in a reaction are those required to describe the initial and final channels, and DI studies typically consider these degrees of freedom and no others. Because of this simplicity DI theories may be worked out in painstaking detail. DI processes concern only part of the wave function for a problem. The other part involves complicated excitations of many degrees of freedom, and gives the compound nucleus (CN) effects. While it is extremely interesting to learn how to separate DI and CN effects in an orderly manner, if they are both present in a reaction, no suitable method has yet been found. Instead, current work stresses the kinds of reactions and the kinds of final states in which DI effects dominate and in which CN effects may almost be forgotten. The DI cross-sections which are studied are often extremely large, comparable to elastic scattering cross-sections. (author)

  9. The RIKEN gas-filled recoil separator and a possible new approach to superheavy elements by the (HI, αxn) reaction

    International Nuclear Information System (INIS)

    Nomura, T.

    1990-10-01

    The (HI, αxn) reaction, in which precompound α particle emission takes place, is shown to occur significantly even near the Coulomb barrier. Because the α emission can efficiently cool down a highly excited nucleus both in energy and angular momentum, it is considered to be very effective for production of heavy elements like SHE. However, the angular distributions of residual nuclei produced in this reaction are side-peaked, requiring a recoil-type separator with large angular acceptance when it is applied for collection of the relevant nuclei. A brief description is given about a gas-filled separator recently constructed at RIKEN, which meets the above requirement. (author)

  10. Self-Controlled Synthesis of Hyperbranched Polyetherketones From A3 + B2 Approach Via Different Solubilities of Monomers in the Reaction Medium (Preprint)

    Science.gov (United States)

    2006-10-01

    higher yields than 1a and 2a after the similar work-up procedure, which involved Soxhlet extraction with water for 2 days and methanol for 2 days to get...the co-monomers. One such reaction medium, optimized PPA/P2O5 mixture, has been established for the electrophilic substitution reaction to yield high... Soxhlet -extracted with water for 2 days, methanol for 2 days, and finally dried under reduced pressure (0.05 mmHg) at 100°C for 150 h to give 3.30 g (76

  11. Class 1 Areas

    Data.gov (United States)

    U.S. Environmental Protection Agency — A "Class 1" area is a geographic area recognized by the EPA as being of the highest environmental quality and requiring maximum protection. Class I areas are areas...

  12. PRCR Classes and Activities

    Data.gov (United States)

    Town of Cary, North Carolina — This data is specific to Parks and Recreation classes, workshops, and activities within the course catalog. It contains an entry for upcoming classes.*This data set...

  13. The Character Strengths of Class Clowns

    Directory of Open Access Journals (Sweden)

    Willibald F. Ruch

    2014-09-01

    Full Text Available Class clowns traditionally were studied as a type concept and identified via sociometric procedures. In the present study a variable-centered approach was favored and class clown behaviors were studied in the context of character strengths, orientations to happiness and satisfaction with life. A sample of 672 Swiss children and adolescents filled in an 18 item self-report instrument depicting class clown behaviors. A hierarchical model of class clown behaviors was developed distinguishing a general factor and the four positively correlated dimensions of identified as a class clown, comic talent, disruptive rule-breaker, and subversive joker. Analysis of the general factor showed that class clowns were primarily male, and tended to be seen as class clowns by the teacher. Analyses of the 24 character strengths of the VIA-Youth (Park & Peterson, 2006 showed that class clowns were high in humor and leadership, and low in strengths like prudence, self-regulation, modesty, honesty, fairness, perseverance, and love of learning. An inspection of signature strengths revealed that 75% of class clowns had humor as a signature strength. Furthermore, generally class clown behaviors were shown by students indulging in a life of pleasure, but low life of engagement. The four dimensions yielded different character strengths profiles. While all dimensions of class clowns behaviors were low in temperance strengths, the factors identified as the class clown and comic talent were correlated with leadership strengths and the two negative factors (disruptive rule-breaker, subversive joker were low in other directed strengths. The disruptive rule breaking class clown was additionally low in intellectual strengths. While humor predicted life satisfaction, class clowning tended to go along with diminished satisfaction with life. It is concluded that different types of class clowns need to be kept apart and need different attention by teachers.

  14. The character strengths of class clowns.

    Science.gov (United States)

    Ruch, Willibald; Platt, Tracey; Hofmann, Jennifer

    2014-01-01

    Class clowns traditionally were studied as a type concept and identified via sociometric procedures. In the present study a variable-centered approach was favored and class clown behaviors were studied in the context of character strengths, orientations to happiness and satisfaction with life. A sample of 672 Swiss children and adolescents filled in an 18 item self-report instrument depicting class clown behaviors. A hierarchical model of class clown behaviors was developed distinguishing a general factor and the four positively correlated dimensions of "identified as a class clown," "comic talent," "disruptive rule-breaker," and "subversive joker." Analysis of the general factor showed that class clowns were primarily male, and tended to be seen as class clowns by the teacher. Analyses of the 24 character strengths of the VIA-Youth (Park and Peterson, 2006) showed that class clowns were high in humor and leadership, and low in strengths like prudence, self-regulation, modesty, honesty, fairness, perseverance, and love of learning. An inspection of signature strengths revealed that 75% of class clowns had humor as a signature strength. Furthermore, class clown behaviors were generally shown by students indulging in a life of pleasure, but low life of engagement. The four dimensions yielded different character strengths profiles. While all dimensions of class clowns behaviors were low in temperance strengths, the factors "identified as the class clown" and "comic talent" were correlated with leadership strengths and the two negative factors ("disruptive rule-breaker," "subversive joker") were low in other directed strengths. The disruptive rule breaking class clown was additionally low in intellectual strengths. While humor predicted life satisfaction, class clowning tended to go along with diminished satisfaction with life. It is concluded that different types of class clowns need to be kept apart and need different attention by teachers.

  15. Class Notes for "Class-Y-News."

    Science.gov (United States)

    Stuart, Judy L.

    1991-01-01

    A self-contained class of students with mild to moderate disabilities published a monthly newsletter which was distributed to students' families. Students became involved in writing, typing, drawing, folding, basic editing, and disseminating. (JDD)

  16. Context-sensitive intra-class clustering

    KAUST Repository

    Yu, Yingwei

    2014-02-01

    This paper describes a new semi-supervised learning algorithm for intra-class clustering (ICC). ICC partitions each class into sub-classes in order to minimize overlap across clusters from different classes. This is achieved by allowing partitioning of a certain class to be assisted by data points from other classes in a context-dependent fashion. The result is that overlap across sub-classes (both within- and across class) is greatly reduced. ICC is particularly useful when combined with algorithms that assume that each class has a unimodal Gaussian distribution (e.g., Linear Discriminant Analysis (LDA), quadratic classifiers), an assumption that is not always true in many real-world situations. ICC can help partition non-Gaussian, multimodal distributions to overcome such a problem. In this sense, ICC works as a preprocessor. Experiments with our ICC algorithm on synthetic data sets and real-world data sets indicated that it can significantly improve the performance of LDA and quadratic classifiers. We expect our approach to be applicable to a broader class of pattern recognition problems where class-conditional densities are significantly non-Gaussian or multi-modal. © 2013 Elsevier Ltd. All rights reserved.

  17. Classed identities in adolescence

    OpenAIRE

    Jay, Sarah

    2015-01-01

    peer-reviewed The central argument of this thesis is that social class remains a persistent system of inequality in education, health, life chances and opportunities. Therefore class matters. But why is it that so little attention has been paid to class in the psychological literature? Three papers are presented here which draw together theoretical advances in psychological understandings of group processes and sociological understandings of the complexity of class. As western labour marke...

  18. Reaction mechanisms

    International Nuclear Information System (INIS)

    Nguyen Trong Anh

    1988-01-01

    The 1988 progress report of the Reaction Mechanisms laboratory (Polytechnic School, France), is presented. The research topics are: the valence bond methods, the radical chemistry, the modelling of the transition states by applying geometric constraints, the long range interactions (ion - molecule) in gaseous phase, the reaction sites in gaseous phase and the mass spectroscopy applications. The points of convergence between the investigations of the mass spectroscopy and the theoretical chemistry teams, as well as the purposes guiding the research programs, are discussed. The published papers, the conferences, the congress communications and the thesis, are also reported [fr

  19. A Ring Polymer Molecular Dynamics Approach to Study the Transition between Statistical and Direct Mechanisms in the H2 + H3+ → H3+ + H2 Reaction.

    Science.gov (United States)

    Suleimanov, Yury V; Aguado, Alfredo; Gómez-Carrasco, Susana; Roncero, Octavio

    2018-05-03

    Because of its fundamental importance in astrochemistry, the H 2 + H 3 + → H 3 + + H 2 reaction has been studied experimentally in a wide temperature range. Theoretical studies of the title reaction significantly lag primarily because of the challenges associated with the proper treatment of the zero-point energy (ZPE). As a result, all previous theoretical estimates for the ratio between a direct proton-hop and indirect exchange (via the H 5 + complex) channels deviate from the experiment, in particular, at lower temperatures where the quantum effects dominate. In this work, the ring polymer molecular dynamics (RPMD) method is applied to study this reaction, providing very good agreement with the experiment. RPMD is immune to the shortcomings associated with the ZPE leakage and is able to describe the transition from direct to indirect mechanisms below room temperature. We argue that RPMD represents a useful tool for further studies of numerous ZPE-sensitive chemical reactions that are of high interest in astrochemistry.

  20. Structure of the unbound nucleus 13Be: One-neutron knockout reaction data from 14Be analyzed in a holistic approach

    DEFF Research Database (Denmark)

    Aksyutina, Yu; Aumann, T.; Boretzky, K.

    2013-01-01

    At the ALADIN-LAND setup at GSI the unbound nucleus 13Be has been produced in one-neutron knockout reactions from a 304 MeV/nucleon relativistic beam of 14Be ions impinging on a liquid hydrogen target. An analysis of the data including all available information about 13Be, and in particular recen...

  1. Loosely coupled class families

    DEFF Research Database (Denmark)

    Ernst, Erik

    2001-01-01

    are expressed using virtual classes seem to be very tightly coupled internally. While clients have achieved the freedom to dynamically use one or the other family, it seems that any given family contains a xed set of classes and we will need to create an entire family of its own just in order to replace one...... of the members with another class. This paper shows how to express class families in such a manner that the classes in these families can be used in many dierent combinations, still enabling family polymorphism and ensuring type safety....

  2. Allergic reactions

    Science.gov (United States)

    ... that don't bother most people (such as venom from bee stings and certain foods, medicines, and pollens) can ... person. If the allergic reaction is from a bee sting, scrape the ... more venom. If the person has emergency allergy medicine on ...

  3. Metal-free bioconjugation reactions.

    Science.gov (United States)

    van Berkel, Sander S; van Delft, Floris L

    2013-01-01

    The recent strategy to apply chemical reactions to address fundamental biological questions has led to the emergence of entirely new conjugation reactions that are fast and irreversible, yet so mild and selective that they can be performed even in living cells or organisms. These so-called bioorthogonal reactions open novel avenues, not only in chemical biology research, but also in many other life sciences applications, including the modulation of biopharmaceuticals by site-specific modification approaches.

  4. Bio-waste corn-cob cellulose supported poly(hydroxamic acid) copper complex for Huisgen reaction: Waste to wealth approach.

    Science.gov (United States)

    Mandal, Bablu Hira; Rahman, Md Lutfor; Yusoff, Mashitah Mohd; Chong, Kwok Feng; Sarkar, Shaheen M

    2017-01-20

    Corn-cob cellulose supported poly(hydroxamic acid) Cu(II) complex was prepared by the surface modification of waste corn-cob cellulose through graft copolymerization and subsequent hydroximation. The complex was characterized by IR, UV, FESEM, TEM, XPS, EDX and ICP-AES analyses. The complex has been found to be an efficient catalyst for 1,3-dipolar Huisgen cycloaddition (CuAAC) of aryl/alkyl azides with a variety of alkynes as well as one-pot three-components reaction in the presence of sodium ascorbate to give the corresponding cycloaddition products in up to 96% yield and high turn over number (TON 18,600) and turn over frequency (TOF 930h -1 ) were achieved. The complex was easy to recover from the reaction mixture and reused six times without significant loss of its catalytic activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. A Complementary Isothermal Amplification Method to the U.S. EPA Quantitative Polymerase Chain Reaction Approach for the Detection of Enterococci in Environmental Waters.

    Science.gov (United States)

    Kolm, Claudia; Martzy, Roland; Brunner, Kurt; Mach, Robert L; Krska, Rudolf; Heinze, Georg; Sommer, Regina; Reischer, Georg H; Farnleitner, Andreas H

    2017-06-20

    We report a novel molecular assay, based on helicase-dependent amplification (HDA), for the detection of enterococci as markers for fecal pollution in water. This isothermal assay targets the same Enterococcus 23S rRNA gene region as the existing quantitative polymerase chain reaction (qPCR) assays of U.S. Environmental Protection Agency Methods 1611 and 1609 but can be entirely performed on a simple heating block. The developed Enterococcus HDA assay successfully discriminated 15 enterococcal from 15 non-enterococcal reference strains and reliably detected 48 environmental isolates of enterococci. The limit of detection was 25 target copies per reaction, only 3 times higher than that of qPCR. The applicability of the assay was tested on 30 environmental water sample DNA extracts, simulating a gradient of fecal pollution. Despite the isothermal nature of the reaction, the HDA results were consistent with those of the qPCR reference. Given this performance, we conclude that the developed Enterococcus HDA assay has great potential as a qualitative molecular screening method for resource-limited settings when combined with compatible up- and downstream processes. This amplification strategy can pave the way for developing a new generation of rapid, low-cost, and field-deployable molecular diagnostic tools for water quality monitoring.

  6. Contribution to an effective design method for stationary reaction-diffusion patterns

    Energy Technology Data Exchange (ETDEWEB)

    Szalai, István; Horváth, Judit [Laboratory of Nonlinear Chemical Dynamics, Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, H-1518 Budapest 112 (Hungary); De Kepper, Patrick [Centre de Recherche Paul Pascal, CNRS, University of Bordeaux, 115, Avenue Schweitzer, F-33600 Pessac (France)

    2015-06-15

    The British mathematician Alan Turing predicted, in his seminal 1952 publication, that stationary reaction-diffusion patterns could spontaneously develop in reacting chemical or biochemical solutions. The first two clear experimental demonstrations of such a phenomenon were not made before the early 1990s when the design of new chemical oscillatory reactions and appropriate open spatial chemical reactors had been invented. Yet, the number of pattern producing reactions had not grown until 2009 when we developed an operational design method, which takes into account the feeding conditions and other specificities of real open spatial reactors. Since then, on the basis of this method, five additional reactions were shown to produce stationary reaction-diffusion patterns. To gain a clearer view on where our methodical approach on the patterning capacity of a reaction stands, numerical studies in conditions that mimic true open spatial reactors were made. In these numerical experiments, we explored the patterning capacity of Rabai's model for pH driven Landolt type reactions as a function of experimentally attainable parameters that control the main time and length scales. Because of the straightforward reversible binding of protons to carboxylate carrying polymer chains, this class of reaction is at the base of the chemistry leading to most of the stationary reaction-diffusion patterns presently observed. We compare our model predictions with experimental observations and comment on agreements and differences.

  7. Contribution to an effective design method for stationary reaction-diffusion patterns

    International Nuclear Information System (INIS)

    Szalai, István; Horváth, Judit; De Kepper, Patrick

    2015-01-01

    The British mathematician Alan Turing predicted, in his seminal 1952 publication, that stationary reaction-diffusion patterns could spontaneously develop in reacting chemical or biochemical solutions. The first two clear experimental demonstrations of such a phenomenon were not made before the early 1990s when the design of new chemical oscillatory reactions and appropriate open spatial chemical reactors had been invented. Yet, the number of pattern producing reactions had not grown until 2009 when we developed an operational design method, which takes into account the feeding conditions and other specificities of real open spatial reactors. Since then, on the basis of this method, five additional reactions were shown to produce stationary reaction-diffusion patterns. To gain a clearer view on where our methodical approach on the patterning capacity of a reaction stands, numerical studies in conditions that mimic true open spatial reactors were made. In these numerical experiments, we explored the patterning capacity of Rabai's model for pH driven Landolt type reactions as a function of experimentally attainable parameters that control the main time and length scales. Because of the straightforward reversible binding of protons to carboxylate carrying polymer chains, this class of reaction is at the base of the chemistry leading to most of the stationary reaction-diffusion patterns presently observed. We compare our model predictions with experimental observations and comment on agreements and differences

  8. Novel Reagents for Multi-Component Reactions

    Science.gov (United States)

    Wang, Yanguang; Basso, Andrea; Nenajdenko, Valentine G.; Gulevich, Anton V.; Krasavin, Mikhail; Bushkova, Ekaterina; Parchinsky, Vladislav; Banfi, Luca; Basso, Andrea; Cerulli, Valentina; Guanti, Giuseppe; Riva, Renata; Rozentsveig, Igor B.; Rozentsveig, Gulnur N.; Popov, Aleksandr V.; Serykh, Valeriy J.; Levkovskaya, Galina G.; Cao, Song; Shen, Li; Liu, Nianjin; Wu, Jingjing; Li, Lina; Qian, Xuhong; Chen, Xiaopeng; Wang, Hongbo; Feng, Jinwu; Wang, Yanguang; Lu, Ping; Heravi, Majid M.; Sadjadi, Samaheh; Kazemizadeh, Ali Reza; Ramazani, Ali; Kudyakova, Yulia S.; Goryaeva, Marina V.; Burgart, Yanina V.; Saloutin, Victor I.; Mossetti, Riccardo; Pirali, Tracey; Tron, Gian Cesare; Rozhkova, Yulia S.; Mayorova, Olga A.; Shklyaev, Yuriy V.; Zhdanko, Alexander G.; Nenajdenko, Valentine G.; Stryapunina, Olga G.; Plekhanova, Irina V.; Glushkov, Vladimir A.; Shklyaev, Yurii V.

    Ketenimines are a class of versatile and highly reactive intermediates that can participate in a variety of organic reactions, such as nucleophilic additions, radical additions, [2 + 2] and [2 + 4] cycloadditions, and sigmatropic rearrangements. In this presentation, we report on a series of multi-component reactions that involve a ketenimine intermediate. These reactions could furnish diverse heterocyclic compounds, including functionalized iminocoumarin, iminodihydroqunolines, iminothiochromens, pyrrolines, isoquinolines, pyridines, β-lactams, imino-1,2-dihydrocoumarins, and benzimidazoles.

  9. Class, Culture and Politics

    DEFF Research Database (Denmark)

    Harrits, Gitte Sommer

    2013-01-01

    Even though contemporary discussions of class have moved forward towards recognizing a multidimensional concept of class, empirical analyses tend to focus on cultural practices in a rather narrow sense, that is, as practices of cultural consumption or practices of education. As a result......, discussions within political sociology have not yet utilized the merits of a multidimensional conception of class. In light of this, the article suggests a comprehensive Bourdieusian framework for class analysis, integrating culture as both a structural phenomenon co-constitutive of class and as symbolic...... practice. Further, the article explores this theoretical framework in a multiple correspondence analysis of a Danish survey, demonstrating how class and political practices are indeed homologous. However, the analysis also points at several elements of field autonomy, and the concluding discussion...

  10. Class network routing

    Science.gov (United States)

    Bhanot, Gyan [Princeton, NJ; Blumrich, Matthias A [Ridgefield, CT; Chen, Dong [Croton On Hudson, NY; Coteus, Paul W [Yorktown Heights, NY; Gara, Alan G [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Steinmacher-Burow, Burkhard D [Mount Kisco, NY; Takken, Todd E [Mount Kisco, NY; Vranas, Pavlos M [Bedford Hills, NY

    2009-09-08

    Class network routing is implemented in a network such as a computer network comprising a plurality of parallel compute processors at nodes thereof. Class network routing allows a compute processor to broadcast a message to a range (one or more) of other compute processors in the computer network, such as processors in a column or a row. Normally this type of operation requires a separate message to be sent to each processor. With class network routing pursuant to the invention, a single message is sufficient, which generally reduces the total number of messages in the network as well as the latency to do a broadcast. Class network routing is also applied to dense matrix inversion algorithms on distributed memory parallel supercomputers with hardware class function (multicast) capability. This is achieved by exploiting the fact that the communication patterns of dense matrix inversion can be served by hardware class functions, which results in faster execution times.

  11. Semantic Analysis of Virtual Classes and Nested Classes

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    1999-01-01

    Virtual classes and nested classes are distinguishing features of BETA. Nested classes originated from Simula, but until recently they have not been part of main stream object- oriented languages. C++ has a restricted form of nested classes and they were included in Java 1.1. Virtual classes...... classes and parameterized classes have been made. Although virtual classes and nested classes have been used in BETA for more than a decade, their implementation has not been published. The purpose of this paper is to contribute to the understanding of virtual classes and nested classes by presenting...

  12. Class in disguise

    DEFF Research Database (Denmark)

    Faber, Stine Thidemann; Prieur, Annick

    This paper asks how class can have importance in one of the worlds’ most equal societies: Denmark. The answer is that class here appears in disguised forms. The field under study is a city, Aalborg, in the midst of transition from a stronghold of industrialism to a post industrial economy. The pa....... The paper also raises questions about how sociological discourses may contribute to the veiling of class....

  13. Progress in microscopic direct reaction modeling of nucleon induced reactions

    Energy Technology Data Exchange (ETDEWEB)

    Dupuis, M.; Bauge, E.; Hilaire, S.; Lechaftois, F.; Peru, S.; Pillet, N.; Robin, C. [CEA, DAM, DIF, Arpajon (France)

    2015-12-15

    A microscopic nuclear reaction model is applied to neutron elastic and direct inelastic scatterings, and pre-equilibrium reaction. The JLM folding model is used with nuclear structure information calculated within the quasi-particle random phase approximation implemented with the Gogny D1S interaction. The folding model for direct inelastic scattering is extended to include rearrangement corrections stemming from both isoscalar and isovector density variations occurring during a transition. The quality of the predicted (n,n), (n,n{sup '}), (n,xn) and (n,n{sup '}γ) cross sections, as well as the generality of the present microscopic approach, shows that it is a powerful tool that can help improving nuclear reactions data quality. Short- and long-term perspectives are drawn to extend the present approach to more systems, to include missing reactions mechanisms, and to consistently treat both structure and reaction problems. (orig.)

  14. Quantum Chemical Modeling of Enzymatic Reactions: The Case of Decarboxylation.

    Science.gov (United States)

    Liao, Rong-Zhen; Yu, Jian-Guo; Himo, Fahmi

    2011-05-10

    We present a systematic study of the decarboxylation step of the enzyme aspartate decarboxylase with the purpose of assessing the quantum chemical cluster approach for modeling this important class of decarboxylase enzymes. Active site models ranging in size from 27 to 220 atoms are designed, and the barrier and reaction energy of this step are evaluated. To model the enzyme surrounding, homogeneous polarizable medium techniques are used with several dielectric constants. The main conclusion is that when the active site model reaches a certain size, the solvation effects from the surroundings saturate. Similar results have previously been obtained from systematic studies of other classes of enzymes, suggesting that they are of a quite general nature.

  15. Quasi-classical trajectory approach to the O(1D)+HBr→OH+Br reaction stereo-dynamics on X1A' potential energy surface

    International Nuclear Information System (INIS)

    Li Hong; Zheng Bin; Yin Ji-Qing; Meng Qing-Tian

    2011-01-01

    The vector properties of reaction O( 1 D)+HBr→OH+Br on the potential energy surface (PES) of X 1 A' ground singlet state are studied by using the quasi-classical trajectory (QCT) theory. The polarization-dependent differential cross sections (PDDCSs), the average rotational alignment factor 2 (j' · k)>, as well as the distributions reflecting vector correlations are also computed. The analysis of the results shows that the alignment and the orientation distribution of the rotation angular momentum vector of product molecule OH is influenced by both the effect of heavy—light—heavy (HLH) type mass combination and the deep well of PES. (atomic and molecular physics)

  16. Reactive scattering of H2 from Cu(100): comparison of dynamics calculations based on the specific reaction parameter approach to density functional theory with experiment.

    Science.gov (United States)

    Sementa, L; Wijzenbroek, M; van Kolck, B J; Somers, M F; Al-Halabi, A; Busnengo, H F; Olsen, R A; Kroes, G J; Rutkowski, M; Thewes, C; Kleimeier, N F; Zacharias, H

    2013-01-28

    We present new experimental and theoretical results for reactive scattering of dihydrogen from Cu(100). In the new experiments, the associative desorption of H(2) is studied in a velocity resolved and final rovibrational state selected manner, using time-of-flight techniques in combination with resonance-enhanced multi-photon ionization laser detection. Average desorption energies and rotational quadrupole alignment parameters were obtained in this way for a number of (v = 0, 1) rotational states, v being the vibrational quantum number. Results of quantum dynamics calculations based on a potential energy surface computed with a specific reaction parameter (SRP) density functional, which was derived earlier for dihydrogen interacting with Cu(111), are compared with the results of the new experiments and with the results of previous molecular beam experiments on sticking of H(2) and on rovibrationally elastic and inelastic scattering of H(2) and D(2) from Cu(100). The calculations use the Born-Oppenheimer and static surface approximations. With the functional derived semi-empirically for dihydrogen + Cu(111), a chemically accurate description is obtained of the molecular beam experiments on sticking of H(2) on Cu(100), and a highly accurate description is obtained of rovibrationally elastic and inelastic scattering of D(2) from Cu(100) and of the orientational dependence of the reaction of (v = 1, j = 2 - 4) H(2) on Cu(100). This suggests that a SRP density functional derived for H(2) interacting with a specific low index face of a metal will yield accurate results for H(2) reactively scattering from another low index face of the same metal, and that it may also yield accurate results for H(2) interacting with a defected (e.g., stepped) surface of that same metal, in a system of catalytic interest. However, the description that was obtained of the average desorption energies, of rovibrationally elastic and inelastic scattering of H(2) from Cu(100), and of the

  17. Evaluation and optimized selection of supersaturating drug delivery systems of posaconazole (BCS class 2b) in the gastrointestinal simulator (GIS): An in vitro-in silico-in vivo approach.

    Science.gov (United States)

    Hens, Bart; Bermejo, Marival; Tsume, Yasuhiro; Gonzalez-Alvarez, Isabel; Ruan, Hao; Matsui, Kazuki; Amidon, Gregory E; Cavanagh, Katie L; Kuminek, Gislaine; Benninghoff, Gail; Fan, Jianghong; Rodríguez-Hornedo, Naír; Amidon, Gordon L

    2018-03-30

    Supersaturating drug delivery systems (SDDS) have been put forward in the recent decades in order to circumvent the issue of low aqueous solubility. Prior to the start of clinical trials, these enabling formulations should be adequately explored in in vitro/in silico studies in order to understand their in vivo performance and to select the most appropriate and effective formulation in terms of oral bioavailability and therapeutic outcome. The purpose of this work was to evaluate the in vivo performance of four different oral formulations of posaconazole (categorized as a biopharmaceutics classification system (BCS) class 2b compound) based on the in vitro concentrations in the gastrointestinal simulator (GIS), coupled with an in silico pharmacokinetic model to predict their systemic profiles. Recently published intraluminal and systemic concentrations of posaconazole for these formulations served as a reference to validate the in vitro and in silico results. Additionally, the morphology of the formed precipitate of posaconazole was visualized and characterized by optical microscopy studies and thermal analysis. This multidisciplinary work demonstrates an in vitro-in silico-in vivo approach that provides a scientific basis for screening SDDS by a user-friendly formulation predictive dissolution (fPD) device in order to rank these formulations towards their in vivo performance. Copyright © 2018. Published by Elsevier B.V.

  18. THERMOKINETIC STUDY OF THE ZERO, FIRST AND SECOND ORDER REACTIONS IN A PSEUDO-ADIABATIC CALORIMETER: Numerical approach and experimental dat

    Directory of Open Access Journals (Sweden)

    Johanna Mendoza

    2012-11-01

    Full Text Available The signal produced by a pseudo-adiabaticcalorimeter is simulated by numericalsolution of the differential equations thatmodel the chemical kinetics [1], the thermalproperties of the calorimetric cell[2], and the response of the thermistorused as a thermometric sensor [3]. These equations show that the calorimetricsignal is related with concentrationin a complex way. Therefore, a comparisonbetween the signals of the threebasic kinetics reactions (zero, first andsecond order was made, as a first stepto obtain a standard procedure to followchemical kinetics using a calorimeter. Inorder to help understanding this relationship,the initial rate method was applied to the simulated data to assess the relationshipbetween the order and the kineticconstants calculated with those usedfor the simulations. As it was expected,the initial rate method for the calorimetricdata, do not give a slope directly relatedwith the order of the reaction, as itwould be produced, for example, in datafrom a spectrophotometer. However, alinear relationship was found betweenwhat we call the “calorimetric order”and the kinetic order. Finally, the developedprocedure was applied to the studyof the H2O2 decomposition catalyzedwith Fe3+ in homogeneous phase andwith activated carbon in heterogeneousphase, finding the order and the kineticsconstants of the global processes, whichwere in close agreement with those inthe literature.

  19. Quasielastic reactions

    International Nuclear Information System (INIS)

    Hansen, O.

    1983-01-01

    A brief review is presented of the experimental and theoretical situation regarding transfer reactions and inelastic scattering. In the first category there is little (very little) precision data for heavy projectiles and consequently almost no experience with quantitative theoretical analysis. For the inelastic scattering the rather extensive data strongly supports the coupled channels models with collective formfactors. At the most back angles, at intensities about 10 -5 of Rutherford scattering, a second, compound-like mechanism becomes dominant. The description of the interplay of these two opposite mechanisms provides a new challenge for our understanding

  20. Nuclear reactions

    International Nuclear Information System (INIS)

    Corner, J.; Richardson, K.; Fenton, N.

    1990-01-01

    Nuclear reactions' marks a new development in the study of television as an agency of public policy debate. During the Eighties, nuclear energy became a major international issue. The disasters at Three-mile Island and Chernobyl created a global anxiety about its risks and a new sensitivity to it among politicians and journalists. This book is a case-study into documentary depictions of nuclear energy in television and video programmes and into the interpretations and responses of viewers drawn from many different occupational groupings. How are the complex and specialist arguments about benefit, risk and proof conveyed through the different conventions of commentary, interview and film sequence? What symbolic associations does the visual language of television bring to portrayals of the issue? And how do viewers make sense of various and conflicting accounts, connecting what they see and hear on the screen with their pre-existing knowledge, experience and 'civic' expectations. The authors examine some of the contrasting forms and themes which have been used by programme makers to explain and persuade, and then give a sustained analysis of the nature and sources of viewers' own accounts. 'Nuclear Reactions' inquires into the public meanings surrounding energy and the environment, spelling out in its conclusion some of the implications for future media treatments of this issue. It is also a key contribution to the international literature on 'television knowledge' and the processes of active viewing. (author)

  1. Teaching Social Class

    Science.gov (United States)

    Tablante, Courtney B.; Fiske, Susan T.

    2015-01-01

    Discussing socioeconomic status in college classes can be challenging. Both teachers and students feel uncomfortable, yet social class matters more than ever. This is especially true, given increased income inequality in the United States and indications that higher education does not reduce this inequality as much as many people hope. Resources…

  2. Generalized Fourier transforms classes

    DEFF Research Database (Denmark)

    Berntsen, Svend; Møller, Steen

    2002-01-01

    The Fourier class of integral transforms with kernels $B(\\omega r)$ has by definition inverse transforms with kernel $B(-\\omega r)$. The space of such transforms is explicitly constructed. A slightly more general class of generalized Fourier transforms are introduced. From the general theory...

  3. Cutting Class Harms Grades

    Science.gov (United States)

    Taylor, Lewis A., III

    2012-01-01

    An accessible business school population of undergraduate students was investigated in three independent, but related studies to determine effects on grades due to cutting class and failing to take advantage of optional reviews and study quizzes. It was hypothesized that cutting classes harms exam scores, attending preexam reviews helps exam…

  4. Nuclear reactions as structure probes

    International Nuclear Information System (INIS)

    Fernandez, Bernard; Cugnon, Joseph; Roussel-Chomaz, Patricia; Sparenberg, Jean-Marc; Oliveira Santos, Francois de; Bauge, Eric; Poves, Alfredo; Keeley, Nicholas; Simenel, Cedric; Avez, Benoit; Lacroix, Denis; Baye, Daniel; Cortina-Gil, Dolores; Pons, Alexandre

    2007-09-01

    This publication gathers courses which aim at giving a view on new experiments which are performed by using radioactive beams, notably low intensity beams, in different accelerators, and allow the structure of very exotic nuclei to be characterized. Experimental as well as theoretical aspects are thus addressed. The contributions propose: a brief history of nuclear reactions and of instruments used to study them from the discovery of nucleus to the DWBA (Distorted Wave Born Approximation); an overview of nuclear reactions; experimental techniques; the theory of collisions at low energy; resonant elastic scattering, inelastic scattering and astrophysical reactions; to probe nuclear structure with nucleons; shell model and spectroscopic factors; analysis of transfer reactions and determination of spectroscopic factors; microscopic approaches of nuclear dynamics; theoretical aspects of dissociation reactions; experimental aspects of knockout reactions; research in oenology with the chemical characterisation of defective ageing of dry white wines

  5. Astrophysical 3He(α ,γ )7Be and 3H(α ,γ )7Li direct capture reactions in a potential-model approach

    Science.gov (United States)

    Tursunov, E. M.; Turakulov, S. A.; Kadyrov, A. S.

    2018-03-01

    The astrophysical 3He(α ,γ )7Be and 3H(α ,γ )7Li direct capture processes are studied in the framework of the two-body model with potentials of a simple Gaussian form, which describe correctly the phase shifts in the s , p , d , and f waves, as well as the binding energy and the asymptotic normalization constant of the ground p3 /2 and the first excited p1 /2 bound states. It is shown that the E 1 transition from the initial s wave to the final p waves is strongly dominant in both capture reactions. On this basis the s -wave potential parameters are adjusted to reproduce the new data of the LUNA Collaboration around 100 keV and the newest data at the Gamov peak estimated with the help of the observed neutrino fluxes from the sun, S34(23-5+6keV ) =0.548 ±0.054 keV b for the astrophysical S factor of the capture process 3He(α ,γ )7Be . The resulting model describes well the astrophysical S factor in the low-energy big-bang nucleosynthesis region of 180-400 keV; however, it has a tendency to underestimate the data above 0.5 MeV. The energy dependence of the S factor is mostly consistent with the data and the results of the no-core shell model with continuum, but substantially different from the fermionic molecular dynamics model predictions. Two-body potentials, adjusted for the properties of the 7Be nucleus, 3He+α elastic scattering data, and the astrophysical S factor of the 3He(α ,γ )7Be direct capture reaction, are able to reproduce the properties of the 7Li nucleus, the binding energies of the ground 3 /2- and first excited 1 /2- states, and phase shifts of the 3H+α elastic scattering in partial waves. Most importantly, these potential models can successfully describe both absolute value and energy dependence of the existing experimental data for the mirror astrophysical 3H(α ,γ )7Li capture reaction without any additional adjustment of the parameters.

  6. Classes of modules

    CERN Document Server

    Dauns, John

    2006-01-01

    Because traditional ring theory places restrictive hypotheses on all submodules of a module, its results apply only to small classes of already well understood examples. Often, modules with infinite Goldie dimension have finite-type dimension, making them amenable to use with type dimension, but not Goldie dimension. By working with natural classes and type submodules (TS), Classes of Modules develops the foundations and tools for the next generation of ring and module theory. It shows how to achieve positive results by placing restrictive hypotheses on a small subset of the complement submodules, Furthermore, it explains the existence of various direct sum decompositions merely as special cases of type direct sum decompositions. Carefully developing the foundations of the subject, the authors begin by providing background on the terminology and introducing the different module classes. The modules classes consist of torsion, torsion-free, s[M], natural, and prenatural. They expand the discussion by exploring...

  7. Onset of Convection in the Presence of a Precipitation Reaction in a Porous Medium: A Comparison of Linear Stability and Numerical Approaches

    Directory of Open Access Journals (Sweden)

    Parama Ghoshal

    2017-12-01

    Full Text Available Reactive convection in a porous medium has received recent interest in the context of the geological storage of carbon dioxide in saline formations. We study theoretically and numerically the gravitational instability of a diffusive boundary layer in the presence of a first-order precipitation reaction. We compare the predictions from normal mode, linear stability analysis, and nonlinear numerical simulations, and discuss the relative deviations. The application of our findings to the storage of carbon dioxide in a siliciclastic aquifer shows that while the reactive-diffusive layer can become unstable within a timescale of 1 to 1.5 months after the injection of carbon dioxide, it can take almost 10 months for sufficiently vigorous convection to produce a considerable increase in the dissolution flux of carbon dioxide.

  8. A low stringency polymerase chain reaction approach to the identification of Biomphalaria glabrata and B. tenagophila, intermediate snail hosts of Schistosoma mansoni in Brazil

    Directory of Open Access Journals (Sweden)

    Teofânia HDA Vidigal

    1996-12-01

    Full Text Available The low stringency-polymerase chain reaction (LS-PCR with a pair of specific primers for the amplification of the 18S rRNA gene was evaluated as a means of differentiating between the two Schistosoma mansoni intermediate host species in Brazil: Biomphalaria glabrata and B. tenagophila. Individual snails obtained from different states of Brazil were used and the amplification patterns obtained showed a high degree of genetic variability in these species. Nevertheless, 4 and 3 clearly defined specific diagnostic bands was observed in individuals from B. glabrata and B. tenagophila respectively. The detection of snail specific diagnostic bands suggests the possibility of reliable species differentiation at the DNA level using LS-PCR.

  9. Approximations for Markovian multi-class queues with preemptive priorities

    NARCIS (Netherlands)

    van der Heijden, Matthijs C.; van Harten, Aart; Sleptchenko, Andrei

    2004-01-01

    We discuss the approximation of performance measures in multi-class M/M/k queues with preemptive priorities for large problem instances (many classes and servers) using class aggregation and server reduction. We compared our approximations to exact and simulation results and found that our approach

  10. 76 FR 70051 - Establishment of Class D and Amendment of Class E Airspace; Los Angeles, CA

    Science.gov (United States)

    2011-11-10

    ... approach instructions currently require this communication. Also of concern was that the FAA pursues a full... Los Angeles Class B airspace area may provide a unified airspace utilization solution in the Los...

  11. The structural dynamics of social class.

    Science.gov (United States)

    Kraus, Michael W; Park, Jun Won

    2017-12-01

    Individual agency accounts of social class persist in society and even in psychological science despite clear evidence for the role of social structures. This article argues that social class is defined by the structural dynamics of society. Specifically, access to powerful networks, groups, and institutions, and inequalities in wealth and other economic resources shape proximal social environments that influence how individuals express their internal states and motivations. An account of social class that highlights the means by which structures shape and are shaped by individuals guides our understanding of how people move up or down in the social class hierarchy, and provides a framework for interpreting neuroscience studies, experimental paradigms, and approaches that attempt to intervene on social class disparities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Explorations into Chemical Reactions and Biochemical Pathways.

    Science.gov (United States)

    Gasteiger, Johann

    2016-12-01

    A brief overview of the work in the research group of the present author on extracting knowledge from chemical reaction data is presented. Methods have been developed to calculate physicochemical effects at the reaction site. It is shown that these physicochemical effects can quite favourably be used to derive equations for the calculation of data on gas phase reactions and on reactions in solution such as aqueous acidity of alcohols or carboxylic acids or the hydrolysis of amides. Furthermore, it is shown that these physicochemical effects are quite effective for assigning reactions into reaction classes that correspond to chemical knowledge. Biochemical reactions constitute a particularly interesting and challenging task for increasing our understanding of living species. The BioPath.Database is a rich source of information on biochemical reactions and has been used for a variety of applications of chemical, biological, or medicinal interests. Thus, it was shown that biochemical reactions can be assigned by the physicochemical effects into classes that correspond to the classification of enzymes by the EC numbers. Furthermore, 3D models of reaction intermediates can be used for searching for novel enzyme inhibitors. It was shown in a combined application of chemoinformatics and bioinformatics that essential pathways of diseases can be uncovered. Furthermore, a study showed that bacterial flavor-forming pathways can be discovered. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Randomness in multi-step direct reactions

    International Nuclear Information System (INIS)

    Koning, A.J.; Akkermans, J.M.

    1991-01-01

    The authors propose a quantum-statistical framework that provides an integrated perspective on the differences and similarities between the many current models for multi-step direct reactions in the continuum. It is argued that to obtain a statistical theory two physically different approaches are conceivable to postulate randomness, respectively called leading-particle statistics and residual-system statistics. They present a new leading-particle statistics theory for multi-step direct reactions. It is shown that the model of Feshbach et al. can be derived as a simplification of this theory and thus can be founded solely upon leading-particle statistics. The models developed by Tamura et al. and Nishioka et al. are based upon residual-system statistics and hence fall into a physically different class of multi-step direct theories, although the resulting cross-section formulae for the important first step are shown to be the same. The widely used semi-classical models such as the generalized exciton model can be interpreted as further phenomenological simplification of the leading-particle statistics theory

  14. Extent of reaction in open systems with multiple heterogeneous reactions

    Science.gov (United States)

    Friedly, John C.

    1991-01-01

    The familiar batch concept of extent of reaction is reexamined for systems of reactions occurring in open systems. Because species concentrations change as a result of transport processes as well as reactions in open systems, the extent of reaction has been less useful in practice in these applications. It is shown that by defining the extent of the equivalent batch reaction and a second contribution to the extent of reaction due to the transport processes, it is possible to treat the description of the dynamics of flow through porous media accompanied by many chemical reactions in a uniform, concise manner. This approach tends to isolate the reaction terms among themselves and away from the model partial differential equations, thereby enabling treatment of large problems involving both equilibrium and kinetically controlled reactions. Implications on the number of coupled partial differential equations necessary to be solved and on numerical algorithms for solving such problems are discussed. Examples provided illustrate the theory applied to solute transport in groundwater flow.

  15. Polymerase chain reaction and nested-PCR approaches for detecting Cryptosporidium in water catchments of water treatment plants in Curitiba, State of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Silvia Cristina Osaki

    2013-06-01

    Full Text Available Introduction Cryptosporidium is an important protozoan cause of waterborne disease worldwide of concern to public health authorities. To prevent outbreaks of cryptosporidiosis, the monitoring of this parasite in drinking water is necessary. In the present work, the polymerase chain reaction (PCR and nested-PCR techniques were used to detect Cryptosporidium in raw water from catchment points of four water treatment plants (WTP in Curitiba, Paraná, Brazil. Methods First, DNA extraction techniques were tested in samples containing decreasing amount of oocysts in reagent water, and PCR and nested-PCR with specific primers for 18SSU rDNA of Cryptosporidium were conducted to determine their sensitivity. In reagent water, a commercial extraction kit provided the best analytical sensitivity, and PCR and nested-PCR allowed the detection of five and two oocysts, respectively, with the primers XIAOR/XIAOF and XIAO1F/XIAO2R. Results In the spiking experiments, only the PCR with the primers AWA995F/AWA1206R was successful at detecting concentrations of 0.1 oocysts/mL. Two catchments samples of raw water and/or water sludge from four WTPs were contaminated with Cryptosporidium. Conclusions The application of the techniques to monitor Cryptosporidium in water and detect contamination in water catchments of WTPs in Curitiba are discussed in the present work.

  16. A green approach towards adoption of chemical reaction model on 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane decomposition by differential isoconversional kinetic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Das, Mitali; Shu, Chi-Min, E-mail: shucm@yuntech.edu.tw

    2016-01-15

    Highlights: • Thermally degraded DBPH products are identified. • An appropriate mathematical model was selected for decomposition study. • Differential isoconversional analysis was performed to obtain kinetic parameters. • Simulation on thermal analysis model was conducted for the best storage conditions. - Abstract: This study investigated the thermal degradation products of 2,5-dimethyl-2,5-di-(tert-butylperoxy) hexane (DBPH), by TG/GC/MS to identify runaway reaction and thermal safety parameters. It also included the determination of time to maximum rate under adiabatic conditions (TMR{sub ad}) and self-accelerating decomposition temperature obtained through Advanced Kinetics and Technology Solutions. The apparent activation energy (E{sub a}) was calculated from differential isoconversional kinetic analysis method using differential scanning calorimetry experiments. The E{sub a} value obtained by Friedman analysis is in the range of 118.0–149.0 kJ mol{sup −1}. The TMR{sub ad} was 24.0 h with an apparent onset temperature of 82.4 °C. This study has also established an efficient benchmark for a thermal hazard assessment of DBPH that can be applied to assure safer storage conditions.

  17. Identifying classes of persons with mild intellectual disability or borderline intellectual functioning: a latent class analysis.

    Science.gov (United States)

    Nouwens, Peter J G; Lucas, Rosanne; Smulders, Nienke B M; Embregts, Petri J C M; van Nieuwenhuizen, Chijs

    2017-07-17

    Persons with mild intellectual disability or borderline intellectual functioning are often studied as a single group with similar characteristics. However, there are indications that differences exist within this population. Therefore, the aim of this study was to identify classes of persons with mild intellectual disability or borderline intellectual functioning and to examine whether these classes are related to individual and/or environmental characteristics. Latent class analysis was performed using file data of 250 eligible participants with a mean age of 26.1 (SD 13.8, range 3-70) years. Five distinct classes of persons with mild intellectual disability or borderline intellectual functioning were found. These classes significantly differed in individual and environmental characteristics. For example, persons with a mild intellectual disability experienced fewer problems than those with borderline intellectual disability. The identification of five classes implies that a differentiated approach is required towards persons with mild intellectual disability or borderline intellectual functioning.

  18. Social Class Dialogues and the Fostering of Class Consciousness

    Science.gov (United States)

    Madden, Meredith

    2015-01-01

    How do critical pedagogies promote undergraduate students' awareness of social class, social class identity, and social class inequalities in education? How do undergraduate students experience class consciousness-raising in the intergroup dialogue classroom? This qualitative study explores undergraduate students' class consciousness-raising in an…

  19. Social class, dementia and the fourth age.

    Science.gov (United States)

    Jones, Ian Rees

    2017-02-01

    Research addressing social class and dementia has largely focused on measures of socioeconomic status as causal risk factors for dementia and in observed differences in diagnosis, treatment and care. This large body of work has produced important insights but also contains numerous problems and weaknesses. Research needs to take account of the ways in which ageing and social class have been transformed in tandem with the economic, social and cultural coordinates of late modernity. These changes have particular consequences for individual identities and social relations. With this in mind this article adopts a critical gaze on research that considers interactions between dementia and social class in three key areas: (i) epidemiological approaches to inequalities in risk (ii) the role of social class in diagnosis and treatment and (iii) class in the framing of care and access to care. Following this, the article considers studies of dementia and social class that focus on lay understandings and biographical accounts. Sociological insights in this field come from the view that dementia and social class are embedded in social relations. Thus, forms of distinction based on class relations may still play an important role in the lived experience of dementia. © 2017 Foundation for the Sociology of Health & Illness.

  20. Optimizing UML Class Diagrams

    Directory of Open Access Journals (Sweden)

    Sergievskiy Maxim

    2018-01-01

    Full Text Available Most of object-oriented development technologies rely on the use of the universal modeling language UML; class diagrams play a very important role in the design process play, used to build a software system model. Modern CASE tools, which are the basic tools for object-oriented development, can’t be used to optimize UML diagrams. In this manuscript we will explain how, based on the use of design patterns and anti-patterns, class diagrams could be verified and optimized. Certain transformations can be carried out automatically; in other cases, potential inefficiencies will be indicated and recommendations given. This study also discusses additional CASE tools for validating and optimizing of UML class diagrams. For this purpose, a plugin has been developed that analyzes an XMI file containing a description of class diagrams.

  1. Classes of Heart Failure

    Science.gov (United States)

    ... Introduction Types of Heart Failure Classes of Heart Failure Heart Failure in Children Advanced Heart Failure • Causes and ... and Advanced HF • Tools and Resources • Personal Stories Heart Failure Questions to Ask Your Doctor Use these questions ...

  2. First-Class Object Sets

    DEFF Research Database (Denmark)

    Ernst, Erik

    Typically, objects are monolithic entities with a fixed interface. To increase the flexibility in this area, this paper presents first-class object sets as a language construct. An object set offers an interface which is a disjoint union of the interfaces of its member objects. It may also be used...... for a special kind of method invocation involving multiple objects in a dynamic lookup process. With support for feature access and late-bound method calls object sets are similar to ordinary objects, only more flexible. The approach is made precise by means of a small calculus, and the soundness of its type...

  3. Generalized Fourier transforms classes

    DEFF Research Database (Denmark)

    Berntsen, Svend; Møller, Steen

    2002-01-01

    The Fourier class of integral transforms with kernels $B(\\omega r)$ has by definition inverse transforms with kernel $B(-\\omega r)$. The space of such transforms is explicitly constructed. A slightly more general class of generalized Fourier transforms are introduced. From the general theory foll...... follows that integral transform with kernels which are products of a Bessel and a Hankel function or which is of a certain general hypergeometric type have inverse transforms of the same structure....

  4. Nordic Walking Classes

    CERN Multimedia

    Fitness Club

    2015-01-01

    Four classes of one hour each are held on Tuesdays. RDV barracks parking at Entrance A, 10 minutes before class time. Spring Course 2015: 05.05/12.05/19.05/26.05 Prices 40 CHF per session + 10 CHF club membership 5 CHF/hour pole rental Check out our schedule and enroll at: https://espace.cern.ch/club-fitness/Lists/Nordic%20Walking/NewForm.aspx? Hope to see you among us! fitness.club@cern.ch

  5. Chain reaction

    International Nuclear Information System (INIS)

    Balogh, Brian.

    1991-01-01

    Chain Reaction is a work of recent American political history. It seeks to explain how and why America came to depend so heavily on its experts after World War II, how those experts translated that authority into political clout, and why that authority and political discretion declined in the 1970s. The author's research into the internal memoranda of the Atomic Energy Commission substantiates his argument in historical detail. It was not the ravages of American anti-intellectualism, as so many scholars have argued, that brought the experts back down to earth. Rather, their decline can be traced to the very roots of their success after World War II. The need to over-state anticipated results in order to garner public support, incessant professional and bureaucratic specialization, and the sheer proliferation of expertise pushed arcane and insulated debates between experts into public forums at the same time that a broad cross section of political participants found it easier to gain access to their own expertise. These tendencies ultimately undermined the political influence of all experts. (author)

  6. Runtime Support for Type-Safe Dynamic Java Classes

    National Research Council Canada - National Science Library

    Malabarba, Scott; Pandey, Raju; Gragg, Jeff; Barr, Earl; Barnes, J. F

    2000-01-01

    .... In this paper we present an approach for supporting dynamic evolution of Java programs. In this approach, Java programs can evolve by changing their components, namely classes, during their execution...

  7. First report on synthesis of ZnFe_2O_4 thin film using successive ionic layer adsorption and reaction: Approach towards solid-state symmetric supercapacitor device

    International Nuclear Information System (INIS)

    Raut, Shrikant S.; Sankapal, Babasaheb R.

    2016-01-01

    Highlights: • First report on synthesis of ZnFe_2O_4 thin film using SILAR method. • ZnFe_2O_4 electrode yields the specific capacitance of 471 Fg"−"1 at a scan rate of 5 mV s"−"1 in 1 M NaOH aqueous solution. • Solid-state symmetric supercapacitor device based on ZnFe_2O_4 sandwiched in polyvinyl alcohol (PVA)–LiClO_4 gel electrolyte exhibits voltage windows of 1.0 V. • ZnFe_2O_4-SSS supercapacitor device shows good energy and power density with long cycle life. - Abstract: ZnFe_2O_4 thin film has been synthesized by a simple and low cost successive ionic layer adsorption and reaction (SILAR) method without the use of surfactant or template. The nanoplate composed of nanoparticles with porous surface morphology has been revealed which is beneficial towards supercapacitor application. Formed ZnFe_2O_4 thin film has been tested as an electrode material for supercapacitor through electrochemical analysis. First attempt for SILAR synthesized ZnFe_2O_4 thin film exhibited a specific capacitance of 471 Fg"−"1 at a scan rate of 5 mVs"−"1 in 1 M NaOH aqueous solution. Further, ZnFe_2O_4 solid-state symmetric (SSS) supercapacitor device demonstrated voltage window of 1.0 V with specific capacitance of 32 Fg"−"1, energy density of 4.47 Whkg"−"1 and power density of 277 Wkg"−"1 at 1 Ag"−"1 current density. Such high performance capacitive behavior indicates ZnFe_2O_4 thin film is promising and low cost electrode material towards energy storage devices for various portable electronic systems.

  8. Surface structure and reaction property of CuCl2-PdCl2 bimetallic catalyst in methanol oxycarbonylation: A DFT approach

    International Nuclear Information System (INIS)

    Meng, Qingsen; Wang, Shengping; Shen, Yongli; Yan, Bing; Wu, Yuanxin; Ma, Xinbin

    2014-01-01

    Surface structure of CuCl 2 -PdCl 2 bimetallic catalyst (Wacker-type catalyst) was built employing density functional theory (DFT) calculations, and the reaction mechanism of methanol oxycarbonylation over the CuCl 2 -PdCl 2 surfaces was also investigated. On the CuCl 2 -PdCl 2 surface, the active site for methanol oxidation was confirmed as Cu-Cl-Cu (Pd). Comparing with pure CuCl 2 surface, the introduction of Pd atom causes the electron repopulation on the surface and lowers the energy barrier for methanol oxidation, but the number of the active site decreases with the increasing of Pd doping volume. Agreed with previous experimental results, the Pd site is most favorable for the CO insertion, indicated by the lowest activation barrier for the formation of COOCH 3 on Pd atom. The lowest energy barrier for the formation of DMC appears when COOCH 3 species adsorbed on Pd atom and methoxyl adsorbed on Cu atoms, which is 0.42 eV. Finally, the reconstruction of the unsaturated surface is a spontaneous and exothermic process. Comparing with other surfaces, the rate-limiting step, methanol oxidation, on CuCl 2 -PdCl 2 surface with Pd/Cu = 1:17 has the lowest energy barrier, which is agreed with the experimental observation that PdCl 2 -CuCl 2 catalyst with Pd/Cu = 1:20 has the favorable activity. The adsorbed methoxyl will further lower the activation barrier of methanol oxidation, which is agreed with experimental observation that the Wacker-type catalysts have an induction period in the methanol oxidative carbonylation system.

  9. Surface structure and reaction property of CuCl{sub 2}-PdCl{sub 2} bimetallic catalyst in methanol oxycarbonylation: A DFT approach

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Qingsen [Key Laboratory for Green Chemical Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Wang, Shengping, E-mail: spwang@tju.edu.cn [Key Laboratory for Green Chemical Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Shen, Yongli; Yan, Bing [Key Laboratory for Green Chemical Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Wu, Yuanxin [School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430073 (China); Ma, Xinbin [Key Laboratory for Green Chemical Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

    2014-02-15

    Surface structure of CuCl{sub 2}-PdCl{sub 2} bimetallic catalyst (Wacker-type catalyst) was built employing density functional theory (DFT) calculations, and the reaction mechanism of methanol oxycarbonylation over the CuCl{sub 2}-PdCl{sub 2} surfaces was also investigated. On the CuCl{sub 2}-PdCl{sub 2} surface, the active site for methanol oxidation was confirmed as Cu-Cl-Cu (Pd). Comparing with pure CuCl{sub 2} surface, the introduction of Pd atom causes the electron repopulation on the surface and lowers the energy barrier for methanol oxidation, but the number of the active site decreases with the increasing of Pd doping volume. Agreed with previous experimental results, the Pd site is most favorable for the CO insertion, indicated by the lowest activation barrier for the formation of COOCH{sub 3} on Pd atom. The lowest energy barrier for the formation of DMC appears when COOCH{sub 3} species adsorbed on Pd atom and methoxyl adsorbed on Cu atoms, which is 0.42 eV. Finally, the reconstruction of the unsaturated surface is a spontaneous and exothermic process. Comparing with other surfaces, the rate-limiting step, methanol oxidation, on CuCl{sub 2}-PdCl{sub 2} surface with Pd/Cu = 1:17 has the lowest energy barrier, which is agreed with the experimental observation that PdCl{sub 2}-CuCl{sub 2} catalyst with Pd/Cu = 1:20 has the favorable activity. The adsorbed methoxyl will further lower the activation barrier of methanol oxidation, which is agreed with experimental observation that the Wacker-type catalysts have an induction period in the methanol oxidative carbonylation system.

  10. Use of length heterogeneity polymerase chain reaction (LH-PCR as non-invasive approach for dietary analysis of Svalbard reindeer, Rangifer tarandus platyrhynchus.

    Directory of Open Access Journals (Sweden)

    Sungbae Joo

    Full Text Available To efficiently investigate the forage preference of Svalbard reindeer (Rangifer tarandus platyrhynchus, we applied length-heterogeneity polymerase chain reaction (LH-PCR based on length differences of internal transcribed spacer (ITS regions of ribosomal RNA (rRNA to fecal samples from R. tarandus platyrhynchus. A length-heterogeneity (LH database was constructed using both collected potential food sources of Svalbard reindeer and fecal samples, followed by PCR, cloning and sequencing. In total, eighteen fecal samples were collected between 2011 and 2012 from 2 geographic regions and 15 samples were successfully amplified by PCR. The LH-PCR analysis detected abundant peaks, 18.6 peaks on an average per sample, ranging from 100 to 500 bp in size and showing distinct patterns associated with both regions and years of sample collection. Principal component analysis (PCA resulted in clustering of 15 fecal samples into 3 groups by the year of collection and region with a statistically significant difference at 99.9% level. The first 2 principal components (PCs explained 71.1% of the total variation among the samples. Through comparison with LH database and identification by cloning and sequencing, lichens (Stereocaulon sp. and Ochrolechia sp. and plant species (Salix polaris and Saxifraga oppositifolia were detected as the food sources that contributed most to the Svalbard reindeer diet. Our results suggest that the use of LH-PCR analysis would be a non-invasive and efficient monitoring tool for characterizing the foraging strategy of Svalbard reindeer. Additionally, combining sequence information would increase its resolving power in identification of foraged diet components.

  11. Chemical potential and reaction electronic flux in symmetry controlled reactions.

    Science.gov (United States)

    Vogt-Geisse, Stefan; Toro-Labbé, Alejandro

    2016-07-15

    In symmetry controlled reactions, orbital degeneracies among orbitals of different symmetries can occur along a reaction coordinate. In such case Koopmans' theorem and the finite difference approximation provide a chemical potential profile with nondifferentiable points. This results in an ill-defined reaction electronic flux (REF) profile, since it is defined as the derivative of the chemical potential with respect to the reaction coordinate. To overcome this deficiency, we propose a new way for the calculation of the chemical potential based on a many orbital approach, suitable for reactions in which symmetry is preserved. This new approach gives rise to a new descriptor: symmetry adapted chemical potential (SA-CP), which is the chemical potential corresponding to a given irreducible representation of a symmetry group. A corresponding symmetry adapted reaction electronic flux (SA-REF) is also obtained. Using this approach smooth chemical potential profiles and well defined REFs are achieved. An application of SA-CP and SA-REF is presented by studying the Cs enol-keto tautomerization of thioformic acid. Two SA-REFs are obtained, JA'(ξ) and JA'' (ξ). It is found that the tautomerization proceeds via an in-plane delocalized 3-center 4-electron O-H-S hypervalent bond which is predicted to exist only in the transition state (TS) region. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Insect bite reactions

    Directory of Open Access Journals (Sweden)

    Sanjay Singh

    2013-01-01

    Full Text Available Insects are a class of living creatures within the arthropods. Insect bite reactions are commonly seen in clinical practice. The present review touches upon the medically important insects and their places in the classification, the sparse literature on the epidemiology of insect bites in India, and different variables influencing the susceptibility of an individual to insect bites. Clinical features of mosquito bites, hypersensitivity to mosquito bites Epstein-Barr virus NK (HMB-EBV-NK disease, eruptive pseudoangiomatosis, Skeeter syndrome, papular pruritic eruption of HIV/AIDS, and clinical features produced by bed bugs, Mexican chicken bugs, assassin bugs, kissing bugs, fleas, black flies, Blandford flies, louse flies, tsetse flies, midges, and thrips are discussed. Brief account is presented of the immunogenic components of mosquito and bed bug saliva. Papular urticaria is discussed including its epidemiology, the 5 stages of skin reaction, the SCRATCH principle as an aid in diagnosis, and the recent evidence supporting participation of types I, III, and IV hypersensitivity reactions in its causation is summarized. Recent developments in the treatment of pediculosis capitis including spinosad 0.9% suspension, benzyl alcohol 5% lotion, dimethicone 4% lotion, isopropyl myristate 50% rinse, and other suffocants are discussed within the context of evidence derived from randomized controlled trials and key findings of a recent systematic review. We also touch upon a non-chemical treatment of head lice and the ineffectiveness of egg-loosening products. Knockdown resistance (kdr as the genetic mechanism making the lice nerves insensitive to permethrin is discussed along with the surprising contrary clinical evidence from Europe about efficacy of permethrin in children with head lice carrying kdr-like gene. The review also presents a brief account of insects as vectors of diseases and ends with discussion of prevention of insect bites and some

  13. An efficient nonlinear finite-difference approach in the computational modeling of the dynamics of a nonlinear diffusion-reaction equation in microbial ecology.

    Science.gov (United States)

    Macías-Díaz, J E; Macías, Siegfried; Medina-Ramírez, I E

    2013-12-01

    In this manuscript, we present a computational model to approximate the solutions of a partial differential equation which describes the growth dynamics of microbial films. The numerical technique reported in this work is an explicit, nonlinear finite-difference methodology which is computationally implemented using Newton's method. Our scheme is compared numerically against an implicit, linear finite-difference discretization of the same partial differential equation, whose computer coding requires an implementation of the stabilized bi-conjugate gradient method. Our numerical results evince that the nonlinear approach results in a more efficient approximation to the solutions of the biofilm model considered, and demands less computer memory. Moreover, the positivity of initial profiles is preserved in the practice by the nonlinear scheme proposed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. 'Sum rules' for preequilibrium reactions

    International Nuclear Information System (INIS)

    Hussein, M.S.

    1981-03-01

    Evidence that suggests a correct relationship between the optical transmission matrix, P, and the several correlation widths, gamma sub(n), found in nsmission matrix, P, and the several correlation widths, n, found in multistep compound (preequilibrium) nuclear reactions, is presented. A second sum rule is also derived within the shell model approach to nuclear reactions. Indications of the potential usefulness of the sum rules in preequilibrium studies are given. (Author) [pt

  15. A Combined Probe-Molecule, Mössbauer, Nuclear Resonance Vibrational Spectroscopy, and Density Functional Theory Approach for Evaluation of Potential Iron Active Sites in an Oxygen Reduction Reaction Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Kneebone, Jared L. [Univ. of Rochester, Rochester, NY (United States); Daifuku, Stephanie L. [Univ. of Rochester, Rochester, NY (United States); Kehl, Jeffrey A. [Univ. of Rochester, Rochester, NY (United States); Wu, Gang [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chung, Hoon T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hu, Michael Y. [Argonne National Lab. (ANL), Argonne, IL (United States); Alp, E. Ercan [Argonne National Lab. (ANL), Argonne, IL (United States); More, Karren L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zelenay, Piotr [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Holby, Edward F. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Neidig, Michael L. [Univ. of Rochester, Rochester, NY (United States)

    2017-07-06

    While non-precious metal M-N-C (M = Fe or Co) catalysts have been developed that are effective for the oxygen reduction reaction in polymer electrolyte fuel cells, no consensus has yet been reached regarding the nature of the M sites in these heterogeneous catalysts that are responsible for reaction with dioxygen (O2). While multiple studies have developed correlations between Fe distributions in as-prepared catalysts and ORR activity, the direct identification of sites reactive towards O2 or O2-analog molecules remains a significant challenge. In the present study, we demonstrate a new approach to identifying and characterizing potential Fe active sites in complex ORR catalysts that combines an effective probe molecule (NO(g)) Mössbauer spectroscopy and nuclear resonance vibrational spectroscopy (NRVS) with density functional theory (DFT) calculations. Mössbauer spectroscopic studies demonstrate that NO(g) treatment of electrochemically reduced PANI-57Fe-C leads to selective reaction with only a sub-set of the Fe species present. Nuclear resonance vibrational spectroscopic studies identified new Fe-ligand vibrations associated with the site reactive towards NO(g). DFT calculations of vibrational properties of a small selection of previously proposed active site structures suggest that graphene zig-zag edge hosted Fe-N structures may be responsible for the observed vibrational behavior with NO(g) probe molecules. Moreover, such sites are likely also reactive to O2, possibly serving as the ORR active sites in the synthesized materials.

  16. Comparing chemical reaction networks

    DEFF Research Database (Denmark)

    Cardelli, Luca; Tribastone, Mirco; Tschaikowski, Max

    2017-01-01

    We study chemical reaction networks (CRNs) as a kernel model of concurrency provided with semantics based on ordinary differential equations. We investigate the problem of comparing two CRNs, i.e., to decide whether the solutions of a source and of a target CRN can be matched for an appropriate...... choice of initial conditions. Using a categorical framework, we extend and unify model-comparison approaches based on dynamical (semantic) and structural (syntactic) properties of CRNs. Then, we provide an algorithm to compare CRNs, running linearly in time with respect to the cardinality of all possible...... comparisons. Finally, using a prototype implementation, CAGE, we apply our results to biological models from the literature....

  17. Correlations analysis of the light particles emitted in the 129 Xe + 48 Ti reaction at 45 MeV/nucleon in the framework of a quantum mechanical approach

    International Nuclear Information System (INIS)

    Nouais, D.

    1996-01-01

    This thesis is composed of four chapter. The first one presents a quantum mechanical model able to describe the light particle correlations by taking into account the nuclear and Coulomb final state particle interactions as well as the influence of the Coulomb field of the emitting nucleus. This model was applied to the analysis of the experimental data obtained from the sequential di-excitation of a quasi-projectile formed in the 129 Xe + 48 Ti at 45 MeV/nucleon. An adaptation of the SPEG spectrometer allowed the measurements of the proton-proton coincidence studies in the range of very low relative momenta (1-10 MeV/c). For such values the proton-proton correlation function is sensible indeed to the proton emission time separation. In case of the protons, the analysis allowed to deduce a lifetime value exceeding 1500 fm/c while for the p-d, d-d and t-t particle couples, the lifetime values were much shorter. This study showed that the deuterons as well as the tritons and alpha particles are emitted prior to the proton emission. The limits of the description of particle emission from a static source have led to consider the influence of dynamical phenomena on the correlation function. This approach made use of a QMD transport model.. The important influence on the correlation function of the dynamic correlations between the momenta and space-time coordinates of the emitting particles was made evident. It is pointed out that the experimental proton-proton correlation function was not possible to be reproduced through QMD theoretical predictions. The momentum variations observed between the particle emission moment in a mean field and its asymptotical value, points to the necessity of a fine description of the interactions

  18. MIDDLE CLASS MOVEMENTS

    OpenAIRE

    Dr. K. Sravana Kumar

    2016-01-01

    The middle class is placed between labour and capital. It neither directly awns the means of production that pumps out the surplus generated by wage labour power, nor does it, by its own labour, produce the surplus which has use and exchange value. Broadly speaking, this class consists of the petty bourgeoisie and the white-collar workers. The former are either self-employed or involved in the distribution of commodities and the latter are non-manual office workers, supervisors and profession...

  19. Talking Class in Tehroon

    DEFF Research Database (Denmark)

    Elling, Rasmus Christian; Rezakhani, Khodadad

    2016-01-01

    Persian, like any other language, is laced with references to class, both blatant and subtle. With idioms and metaphors, Iranians can identify and situate others, and thus themselves, within hierarchies of social status and privilege, both real and imagined. Some class-related terms can be traced...... back to medieval times, whereas others are of modern vintage, the linguistic legacy of television shows, pop songs, social media memes or street vernacular. Every day, it seems, an infectious set of phrases appears that make yesterday’s seem embarrassingly antiquated....

  20. Social Class and Work-Related Decisions: Measurement, Theory, and Social Mobility

    Science.gov (United States)

    Fouad, Nadya A.; Fitzpatrick, Mary E.

    2009-01-01

    In this reaction to Diemer and Ali's article, "Integrating Social Class Into Vocational Psychology: Theory and Practice Implications," the authors point out concerns with binary schema of social class, highlight the contribution of social class to the social cognitive career theory, argue for a more nuanced look at ways that work…

  1. Chemical kinetics and reaction mechanism

    International Nuclear Information System (INIS)

    Jung, Ou Sik; Park, Youn Yeol

    1996-12-01

    This book is about chemical kinetics and reaction mechanism. It consists of eleven chapters, which deal with reaction and reaction speed on reaction mechanism, simple reaction by rate expression, reversible reaction and simultaneous reaction, successive reaction, complicated reaction mechanism, assumption for reaction mechanism, transition state theory, successive reaction and oscillating reaction, reaction by solution, research method high except kinetics on reaction mechanism, high reaction of kinetics like pulsed radiolysis.

  2. Phase transition universality classes of classical, nonequilibrium systems

    CERN Document Server

    Ódor, G

    2004-01-01

    In the first chapter I summarize the most important critical exponents and relations used in this work. In the second chapter I briefly address the question of scaling behavior at first order phase transitions.In chapter three I review dynamical extensions of basic static classes, show the effect of mixing dynamics and percolation behavior. The main body of this work is given in chapter four where genuine, dynamical universality classes specific to nonequilibrium systems are introduced. In chapter five I continue overviewing such nonequilibrium classes but in coupled, multi-component systems. Most of known transitions in low dimensional systems are between active and absorbing states of reaction-diffusion type systems, but I briefly introduce related classes that appear in interface growth models in chapter six. Some of them are related to critical behavior of coupled, multi-component systems. Finally in chapter seven I summarize families of absorbing state system classes, mean-field classes and the most freq...

  3. Use of nanostructure initiator mass spectrometry (NIMS to deduce selectivity of reaction in glycoside hydrolases

    Directory of Open Access Journals (Sweden)

    Kai eDeng

    2015-10-01

    Full Text Available Chemically synthesized nanostructure-initiator mass spectrometry (NIMS probes derivatized with tetrasaccharides were used to study the reactivity of representative Clostridium thermocellum β-glucosidase, endoglucanases and cellobiohydrolase. Diagnostic patterns for reactions of these different classes of enzymes were observed. Results show sequential removal of glucose by the β-glucosidase and a progressive increase in specificity of reaction from endoglucanases to cellobiohydrolase. Time-dependent reactions of these polysaccharide-selective enzymes were modeled by numerical integration, which provides a quantitative basis to make functional distinctions among a continuum of naturally evolved catalytic properties. Consequently, our method, which combines automated protein translation with high-sensitivity and time-dependent detection of multiple products, provides a new approach to annotate glycoside hydrolase phylogenetic trees with functional measurements.

  4. Second class weak currents

    International Nuclear Information System (INIS)

    Delorme, J.

    1978-01-01

    The definition and general properties of weak second class currents are recalled and various detection possibilities briefly reviewed. It is shown that the existing data on nuclear beta decay can be consistently analysed in terms of a phenomenological model. Their implication on the fundamental structure of weak interactions is discussed [fr

  5. World Class Teachers.

    Science.gov (United States)

    Mitchell, Rosalita

    1998-01-01

    School communities are challenged to find ways to identify good teachers and give other teachers a chance to learn from them. The New Mexico World Class Teacher Project is encouraging teachers to pursue certification by the National Board for Professional Teaching Standards. This process sharpens teachers' student assessment skills and encourages…

  6. EPA Web Training Classes

    Science.gov (United States)

    Scheduled webinars can help you better manage EPA web content. Class topics include Drupal basics, creating different types of pages in the WebCMS such as document pages and forms, using Google Analytics, and best practices for metadata and accessibility.

  7. Class Actions in Denmark

    DEFF Research Database (Denmark)

    Werlauff, Erik

    2009-01-01

    The article deals with the relatively new Danish Act on Class Action (Danish: gruppesøgsmål) which was suggested by The Permanent Council on Civil procedure (Retsplejerådet) of which the article's author is a member. The operability of the new provisions is illustrated through some wellknown Danish...

  8. Coming out in Class

    Science.gov (United States)

    McKinnon, Rachel

    2012-01-01

    This article shares how the author explained her trans status to her students. Everyone has been extremely supportive of her decision to come out in class and to completely mask the male secondary-sex characteristics, especially in the workplace. The department chair and the faculty in general have been willing to do whatever they can to assist…

  9. Working Together in Class

    Directory of Open Access Journals (Sweden)

    Pateşan Marioara

    2017-12-01

    Full Text Available The scores obtained by the military students are very important as a lot of opportunities depend on them: the choice of the branch, selection for different in and off-campus activities, the appointment to the workplace and so on. A qualifier, regardless of its form of effective expression, can make a difference in a given context of issuing a value judgment, in relation to the student's performance assessment. In our research we tried to find out what motives students, what determines them to get actively involved in the tasks they are given and the ways we can improve their participation in classes and assignments. In order to have an educated generation we need to have not only well prepared teachers but ones that are open-minded, flexible and in pace with the methodological novelties that can improve the teaching learning process in class. Along the years we have noticed that in classes where students constituted a cohesive group with an increasing degree of interaction between members, the results were better than in a group that did not appreciate team-work. In this article we want to highlight the fact that a teacher can bring to class the appropriate methods and procedures can contribute decisively to the strengthening of the group cohesion and high scores.

  10. Adeus à classe trabalhadora?

    Directory of Open Access Journals (Sweden)

    Geoff Eley

    2013-12-01

    Full Text Available No início da década de 1980, a política centrada em classes da tradição socialista estava em crise, e comentadores importantes adotaram tons apocalípticos. No final da década, a esquerda permanecia profundamente dividida entre os advogados da mudança e os defensores da fé. Em meados dos anos 1990, os primeiros tinham, de modo geral, ganhado a batalha. O artigo busca apresentar essa mudança contemporânea não como a 'morte da classe', mas como o desa­parecimento de um tipo particular de ­sociedade de classes, marcado pelo ­processo de formação da classe trabalhadora entre os anos 1880 e 1940 e pelo alinhamento político daí resultante, atingindo seu apogeu na construção social-democrata do acordo do pós-guerra. Quando mudanças de longo prazo na economia se combinaram com o ataque ao keynesianismo na política de recessão a partir de meados da década de 1970, a unidade da classe trabalhadora deixou de estar disponível da forma antiga e bastante utilizada, como o terreno natural da política de esquerda. Enquanto uma coletividade dominante da classe trabalhadora entrou em declínio, outra se corporificou de modo lento e desigual para tomar o lugar daquela. Mas a unidade operacional dessa nova agregação da classe trabalhadora ainda está, em grande parte, em formação. Para recuperar a eficácia política da tradição socialista, alguma nova visão de agência política coletiva será necessária, uma visão imaginativamente ajustada às condições emergentes da produção e acumulação capitalista no início do século XXI.

  11. Interfacial reactions in intermetallic matrix composites

    International Nuclear Information System (INIS)

    Cantrell, L.B.; Clevenger, E.M.; Perepezko, J.H.

    1993-01-01

    The thermal stability of advanced composites is dominated by the behavior of internal interfaces. Analysis of these internal interfaces often involves consideration of at least ternary order phase equilibria. Limited thermodynamic data exists for ternary and higher order systems. However, a combined approach based upon the use of binary data to estimate ternary phase equilibria and experimentally determined reaction pathways is effective in the analysis of interface reactions in composite systems. In blended powder samples, thermal analysis was used to find possible reaction temperatures, while X-ray analysis, EDS, and EPMA of diffusion couples were used to assess interdiffusion reaction pathways. The approach is illustrated by compatibility studies between TiAl and TiSi 2 at 1,100 C, and in-situ reactions between B 4 C and TiAl at 1300 C where multiple reaction sequences have been analyzed to provide guidance for the design of in-situ reaction processing of composites

  12. Evolutionary change in continuous reaction norms

    DEFF Research Database (Denmark)

    Murren, Courtney J; Maclean, Heidi J; Diamond, Sarah E

    2014-01-01

    Understanding the evolution of reaction norms remains a major challenge in ecology and evolution. Investigating evolutionary divergence in reaction norm shapes between populations and closely related species is one approach to providing insights. Here we use a meta-analytic approach to compare...... divergence in reaction norms of closely related species or populations of animals and plants across types of traits and environments. We quantified mean-standardized differences in overall trait means (Offset) and reaction norm shape (including both Slope and Curvature). These analyses revealed...... contributed to the best-fitting models, especially for Offset, Curvature, and the total differences (Total) between reaction norms. Congeneric species had greater differences in reaction norms than populations, and novel environmental conditions increased the differences in reaction norms between populations...

  13. Nonequilibrium thermodynamics and a fluctuation theorem for individual reaction steps in a chemical reaction network

    International Nuclear Information System (INIS)

    Pal, Krishnendu; Das, Biswajit; Banerjee, Kinshuk; Gangopadhyay, Gautam

    2015-01-01

    We have introduced an approach to nonequilibrium thermodynamics of an open chemical reaction network in terms of the propensities of the individual elementary reactions and the corresponding reverse reactions. The method is a microscopic formulation of the dissipation function in terms of the relative entropy or Kullback-Leibler distance which is based on the analogy of phase space trajectory with the path of elementary reactions in a network of chemical process. We have introduced here a fluctuation theorem valid for each opposite pair of elementary reactions which is useful in determining the contribution of each sub-reaction on the nonequilibrium thermodynamics of overall reaction. The methodology is applied to an oligomeric enzyme kinetics at a chemiostatic condition that leads the reaction to a nonequilibrium steady state for which we have estimated how each step of the reaction is energy driven or entropy driven to contribute to the overall reaction. (paper)

  14. Revisiting Parametric Types and Virtual Classes

    DEFF Research Database (Denmark)

    Madsen, Anders Bach; Ernst, Erik

    2010-01-01

    manner, because virtual classes are closely tied to nominal typing. This paper adds new insight about the dichotomy between these two approaches; it illustrates how virtual constraints and type refinements, as recently introduced in gbeta and Scala, enable structural treatment of virtual types; finally...

  15. A Data Mining Approach to Study the Impact of the Methodology Followed in Chemistry Lab Classes on the Weight Attributed by the Students to the Lab Work on Learning and Motivation

    Science.gov (United States)

    Figueiredo, M.; Esteves, L.; Neves, J.; Vicente, H.

    2016-01-01

    This study reports the use of data mining tools in order to examine the influence of the methodology used in chemistry lab classes, on the weight attributed by the students to the lab work on learning and own motivation. The answer frequency analysis was unable to discriminate the opinions expressed by the respondents according to the type of the…

  16. Optimized reaction mechanism rate rules for ignition of normal alkanes

    KAUST Repository

    Cai, Liming; Pitsch, Heinz; Mohamed, Samah; Raman, Venkat; Bugler, John; Curran, Henry; Sarathy, Mani

    2016-01-01

    fidelity reacting flow simulations capable of improving combustor design and operation. The development of such models for many new fuel components and/or surrogate molecules is greatly facilitated by the application of reaction classes and rate rules

  17. Molecular Interactions and Reaction Dynamics in Supercritical Water Oxidation

    National Research Council Canada - National Science Library

    Johnston, K

    1998-01-01

    .... From UV-vis spectroscopic measurements and molecular dynamics simulation of chemical equilibria, we have shown that density effects on broad classes of reactions may be explained in terms of changes...

  18. Storytelling in EFL Classes

    Directory of Open Access Journals (Sweden)

    Emine Bala

    2015-12-01

    Full Text Available Storytelling is one of the oldest ways of education and oral tradition that is continuously being used to transfer the previous nation‘s cultures, tradition and customs. It constructs a bridge between the new and the old. Storytelling in EFL classes usually provides a meaningful context, interesting atmosphere and is used as a tool to highly motivate students. Although it seems to be mostly based on speaking, it is used to promote other skills such as writing, reading, and listening. Storytelling is mainly regarded to be grounded on imitation and repetition; nevertheless many creative activities can be implemented in the classroom since this method directs learners to use their imaginations. This study discusses the importance of storytelling as a teaching method, and it outlines the advantages of storytelling in EFL classes.

  19. Queen elizabeth class battleships

    CERN Document Server

    Brown, Les

    2010-01-01

    The 'ShipCraft' series provides in-depth information about building and modifying model kits of famous warship types. Lavishly illustrated, each book takes the modeller through a brief history of the subject class, highlighting differences between sister-ships and changes in their appearance over their careers. This includes paint schemes and camouflage, featuring colour profiles and highly detailed line drawings and scale plans. The modelling section reviews the strengths and weaknesses of available kits, lists commercial accessory sets for super-detailing of the ships, and provides hints on modifying and improving the basic kit. This is followed by an extensive photographic survey of selected high-quality models in a variety of scales, and the book concludes with a section on research references - books, monographs, large-scale plans and relevant websites.This volume covers the five ships of the highly successful Queen Elizabeth class, a design of fast battleship that set the benchmark for the last generati...

  20. World Class Facilities Management

    DEFF Research Database (Denmark)

    Malmstrøm, Ole Emil; Jensen, Per Anker

    2013-01-01

    Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet.......Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet....